linux/fs/nfs/nfs4namespace.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/nfs/nfs4namespace.c
*
* Copyright (C) 2005 Trond Myklebust <Trond.Myklebust@netapp.com>
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
* - Modified by David Howells <dhowells@redhat.com>
*
* NFSv4 namespace
*/
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
#include <linux/module.h>
#include <linux/dcache.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/addr.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include "internal.h"
#include "nfs4_fs.h"
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
#include "nfs.h"
#include "dns_resolve.h"
#define NFSDBG_FACILITY NFSDBG_VFS
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
/*
* Work out the length that an NFSv4 path would render to as a standard posix
* path, with a leading slash but no terminating slash.
*/
static ssize_t nfs4_pathname_len(const struct nfs4_pathname *pathname)
{
ssize_t len = 0;
int i;
for (i = 0; i < pathname->ncomponents; i++) {
const struct nfs4_string *component = &pathname->components[i];
if (component->len > NAME_MAX)
goto too_long;
len += 1 + component->len; /* Adding "/foo" */
if (len > PATH_MAX)
goto too_long;
}
return len;
too_long:
return -ENAMETOOLONG;
}
/*
* Convert the NFSv4 pathname components into a standard posix path.
*/
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
static char *nfs4_pathname_string(const struct nfs4_pathname *pathname,
unsigned short *_len)
{
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
ssize_t len;
char *buf, *p;
int i;
len = nfs4_pathname_len(pathname);
if (len < 0)
return ERR_PTR(len);
*_len = len;
p = buf = kmalloc(len + 1, GFP_KERNEL);
if (!buf)
return ERR_PTR(-ENOMEM);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
for (i = 0; i < pathname->ncomponents; i++) {
const struct nfs4_string *component = &pathname->components[i];
*p++ = '/';
memcpy(p, component->data, component->len);
p += component->len;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
*p = 0;
return buf;
}
/*
* return the path component of "<server>:<path>"
* nfspath - the "<server>:<path>" string
* end - one past the last char that could contain "<server>:"
* returns NULL on failure
*/
static char *nfs_path_component(const char *nfspath, const char *end)
{
char *p;
if (*nfspath == '[') {
/* parse [] escaped IPv6 addrs */
p = strchr(nfspath, ']');
if (p != NULL && ++p < end && *p == ':')
return p + 1;
} else {
/* otherwise split on first colon */
p = strchr(nfspath, ':');
if (p != NULL && p < end)
return p + 1;
}
return NULL;
}
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
/*
* Determine the mount path as a string
*/
static char *nfs4_path(struct dentry *dentry, char *buffer, ssize_t buflen)
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
{
char *limit;
char *path = nfs_path(&limit, dentry, buffer, buflen,
NFS_PATH_CANONICAL);
if (!IS_ERR(path)) {
char *path_component = nfs_path_component(path, limit);
if (path_component)
return path_component;
}
return path;
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
}
/*
* Check that fs_locations::fs_root [RFC3530 6.3] is a prefix for what we
* believe to be the server path to this dentry
*/
static int nfs4_validate_fspath(struct dentry *dentry,
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
const struct nfs4_fs_locations *locations,
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
struct nfs_fs_context *ctx)
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
{
const char *path;
char *fs_path;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
unsigned short len;
char *buf;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
int n;
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
buf = kmalloc(4096, GFP_KERNEL);
if (!buf)
return -ENOMEM;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
path = nfs4_path(dentry, buf, 4096);
if (IS_ERR(path)) {
kfree(buf);
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
return PTR_ERR(path);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
}
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
fs_path = nfs4_pathname_string(&locations->fs_path, &len);
if (IS_ERR(fs_path)) {
kfree(buf);
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
return PTR_ERR(fs_path);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
}
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
n = strncmp(path, fs_path, len);
kfree(buf);
kfree(fs_path);
if (n != 0) {
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
dprintk("%s: path %s does not begin with fsroot %s\n",
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
__func__, path, ctx->nfs_server.export_path);
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
return -ENOENT;
}
return 0;
}
size_t nfs_parse_server_name(char *string, size_t len, struct sockaddr_storage *ss,
size_t salen, struct net *net, int port)
{
struct sockaddr *sa = (struct sockaddr *)ss;
ssize_t ret;
ret = rpc_pton(net, string, len, sa, salen);
if (ret == 0) {
ret = rpc_uaddr2sockaddr(net, string, len, sa, salen);
if (ret == 0) {
ret = nfs_dns_resolve_name(net, string, len, ss, salen);
if (ret < 0)
ret = 0;
}
} else if (port) {
rpc_set_port(sa, port);
}
return ret;
}
/**
* nfs_find_best_sec - Find a security mechanism supported locally
* @clnt: pointer to rpc_clnt
* @server: NFS server struct
* @flavors: List of security tuples returned by SECINFO procedure
*
* Return an rpc client that uses the first security mechanism in
* "flavors" that is locally supported. The "flavors" array
* is searched in the order returned from the server, per RFC 3530
* recommendation and each flavor is checked for membership in the
* sec= mount option list if it exists.
*
* Return -EPERM if no matching flavor is found in the array.
*
* Please call rpc_shutdown_client() when you are done with this rpc client.
*
*/
static struct rpc_clnt *nfs_find_best_sec(struct rpc_clnt *clnt,
struct nfs_server *server,
struct nfs4_secinfo_flavors *flavors)
{
rpc_authflavor_t pflavor;
struct nfs4_secinfo4 *secinfo;
unsigned int i;
for (i = 0; i < flavors->num_flavors; i++) {
secinfo = &flavors->flavors[i];
switch (secinfo->flavor) {
case RPC_AUTH_NULL:
case RPC_AUTH_UNIX:
case RPC_AUTH_GSS:
pflavor = rpcauth_get_pseudoflavor(secinfo->flavor,
&secinfo->flavor_info);
/* does the pseudoflavor match a sec= mount opt? */
if (pflavor != RPC_AUTH_MAXFLAVOR &&
nfs_auth_info_match(&server->auth_info, pflavor)) {
struct rpc_clnt *new;
struct rpc_cred *cred;
/* Cloning creates an rpc_auth for the flavor */
new = rpc_clone_client_set_auth(clnt, pflavor);
if (IS_ERR(new))
continue;
/**
* Check that the user actually can use the
* flavor. This is mostly for RPC_AUTH_GSS
* where cr_init obtains a gss context
*/
cred = rpcauth_lookupcred(new->cl_auth, 0);
if (IS_ERR(cred)) {
rpc_shutdown_client(new);
continue;
}
put_rpccred(cred);
return new;
}
}
}
return ERR_PTR(-EPERM);
}
/**
* nfs4_negotiate_security - in response to an NFS4ERR_WRONGSEC on lookup,
* return an rpc_clnt that uses the best available security flavor with
* respect to the secinfo flavor list and the sec= mount options.
*
* @clnt: RPC client to clone
* @inode: directory inode
* @name: lookup name
*
* Please call rpc_shutdown_client() when you are done with this rpc client.
*/
struct rpc_clnt *
nfs4_negotiate_security(struct rpc_clnt *clnt, struct inode *inode,
const struct qstr *name)
{
struct page *page;
struct nfs4_secinfo_flavors *flavors;
struct rpc_clnt *new;
int err;
page = alloc_page(GFP_KERNEL);
if (!page)
return ERR_PTR(-ENOMEM);
flavors = page_address(page);
err = nfs4_proc_secinfo(inode, name, flavors);
if (err < 0) {
new = ERR_PTR(err);
goto out;
}
new = nfs_find_best_sec(clnt, NFS_SERVER(inode), flavors);
out:
put_page(page);
return new;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
static int try_location(struct fs_context *fc,
const struct nfs4_fs_location *location)
{
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
struct nfs_fs_context *ctx = nfs_fc2context(fc);
unsigned int len, s;
char *export_path, *source, *p;
int ret = -ENOENT;
/* Allocate a buffer big enough to hold any of the hostnames plus a
* terminating char and also a buffer big enough to hold the hostname
* plus a colon plus the path.
*/
len = 0;
for (s = 0; s < location->nservers; s++) {
const struct nfs4_string *buf = &location->servers[s];
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
if (buf->len > len)
len = buf->len;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
kfree(ctx->nfs_server.hostname);
ctx->nfs_server.hostname = kmalloc(len + 1, GFP_KERNEL);
if (!ctx->nfs_server.hostname)
return -ENOMEM;
export_path = nfs4_pathname_string(&location->rootpath,
&ctx->nfs_server.export_path_len);
if (IS_ERR(export_path))
return PTR_ERR(export_path);
kfree(ctx->nfs_server.export_path);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
ctx->nfs_server.export_path = export_path;
source = kmalloc(len + 1 + ctx->nfs_server.export_path_len + 1,
GFP_KERNEL);
if (!source)
return -ENOMEM;
kfree(fc->source);
fc->source = source;
for (s = 0; s < location->nservers; s++) {
const struct nfs4_string *buf = &location->servers[s];
if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len))
continue;
ctx->nfs_server.addrlen =
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
nfs_parse_server_name(buf->data, buf->len,
&ctx->nfs_server._address,
sizeof(ctx->nfs_server._address),
fc->net_ns, 0);
if (ctx->nfs_server.addrlen == 0)
continue;
rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
memcpy(ctx->nfs_server.hostname, buf->data, buf->len);
ctx->nfs_server.hostname[buf->len] = '\0';
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
p = source;
memcpy(p, buf->data, buf->len);
p += buf->len;
*p++ = ':';
memcpy(p, ctx->nfs_server.export_path, ctx->nfs_server.export_path_len);
p += ctx->nfs_server.export_path_len;
*p = 0;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
ret = nfs4_get_referral_tree(fc);
if (ret == 0)
return 0;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return ret;
}
/**
* nfs_follow_referral - set up mountpoint when hitting a referral on moved error
* @fc: pointer to struct nfs_fs_context
* @locations: array of NFSv4 server location information
*
*/
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
static int nfs_follow_referral(struct fs_context *fc,
const struct nfs4_fs_locations *locations)
{
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
struct nfs_fs_context *ctx = nfs_fc2context(fc);
int loc, error;
if (locations == NULL || locations->nlocations <= 0)
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return -ENOENT;
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
dprintk("%s: referral at %pd2\n", __func__, ctx->clone_data.dentry);
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
/* Ensure fs path is a prefix of current dentry path */
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
error = nfs4_validate_fspath(ctx->clone_data.dentry, locations, ctx);
if (error < 0)
return error;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
error = -ENOENT;
for (loc = 0; loc < locations->nlocations; loc++) {
const struct nfs4_fs_location *location = &locations->locations[loc];
if (location == NULL || location->nservers <= 0 ||
location->rootpath.ncomponents == 0)
continue;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
error = try_location(fc, location);
if (error == 0)
return 0;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return error;
}
/*
* nfs_do_refmount - handle crossing a referral on server
* @dentry - dentry of referral
*
*/
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
static int nfs_do_refmount(struct fs_context *fc, struct rpc_clnt *client)
{
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct dentry *dentry, *parent;
struct nfs4_fs_locations *fs_locations = NULL;
struct page *page;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
int err = -ENOMEM;
/* BUG_ON(IS_ROOT(dentry)); */
page = alloc_page(GFP_KERNEL);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
if (!page)
return -ENOMEM;
fs_locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
if (!fs_locations)
goto out_free;
fs_locations->fattr = nfs_alloc_fattr();
if (!fs_locations->fattr)
goto out_free_2;
/* Get locations */
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
dentry = ctx->clone_data.dentry;
parent = dget_parent(dentry);
dprintk("%s: getting locations for %pd2\n",
__func__, dentry);
NFS: Share NFS superblocks per-protocol per-server per-FSID The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-08-23 00:06:13 +00:00
err = nfs4_proc_fs_locations(client, d_inode(parent), &dentry->d_name, fs_locations, page);
dput(parent);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
if (err != 0)
goto out_free_3;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
err = -ENOENT;
if (fs_locations->nlocations <= 0 ||
fs_locations->fs_path.ncomponents <= 0)
goto out_free_3;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
err = nfs_follow_referral(fc, fs_locations);
out_free_3:
kfree(fs_locations->fattr);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
out_free_2:
kfree(fs_locations);
out_free:
__free_page(page);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return err;
}
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
int nfs4_submount(struct fs_context *fc, struct nfs_server *server)
{
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct dentry *dentry = ctx->clone_data.dentry;
struct dentry *parent = dget_parent(dentry);
struct inode *dir = d_inode(parent);
struct rpc_clnt *client;
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
int ret;
/* Look it up again to get its attributes and sec flavor */
client = nfs4_proc_lookup_mountpoint(dir, dentry, ctx->mntfh,
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
ctx->clone_data.fattr);
dput(parent);
if (IS_ERR(client))
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return PTR_ERR(client);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
ctx->selected_flavor = client->cl_auth->au_flavor;
if (ctx->clone_data.fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
ret = nfs_do_refmount(fc, client);
} else {
ret = nfs_do_submount(fc);
}
rpc_shutdown_client(client);
NFS: Add fs_context support. Add filesystem context support to NFS, parsing the options in advance and attaching the information to struct nfs_fs_context. The highlights are: (*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This structure represents NFS's superblock config. (*) Make use of the VFS's parsing support to split comma-separated lists (*) Pin the NFS protocol module in the nfs_fs_context. (*) Attach supplementary error information to fs_context. This has the downside that these strings must be static and can't be formatted. (*) Remove the auxiliary file_system_type structs since the information necessary can be conveyed in the nfs_fs_context struct instead. (*) Root mounts are made by duplicating the config for the requested mount so as to have the same parameters. Submounts pick up their parameters from the parent superblock. [AV -- retrans is u32, not string] [SM -- Renamed cfg to ctx in a few functions in an earlier patch] [SM -- Moved fs_context mount option parsing to an earlier patch] [SM -- Moved fs_context error logging to a later patch] [SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()] [SM -- Added is_remount_fc() helper] [SM -- Deferred some refactoring to a later patch] [SM -- Fixed referral mounts, which were broken in the original patch] [SM -- Fixed leak of nfs_fattr when fs_context is freed] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-12-10 12:31:13 +00:00
return ret;
}
/*
* Try one location from the fs_locations array.
*
* Returns zero on success, or a negative errno value.
*/
static int nfs4_try_replacing_one_location(struct nfs_server *server,
char *page, char *page2,
const struct nfs4_fs_location *location)
{
struct net *net = rpc_net_ns(server->client);
struct sockaddr_storage *sap;
unsigned int s;
size_t salen;
int error;
sap = kmalloc(sizeof(*sap), GFP_KERNEL);
if (sap == NULL)
return -ENOMEM;
error = -ENOENT;
for (s = 0; s < location->nservers; s++) {
const struct nfs4_string *buf = &location->servers[s];
char *hostname;
if (buf->len <= 0 || buf->len > PAGE_SIZE)
continue;
if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len) != NULL)
continue;
salen = nfs_parse_server_name(buf->data, buf->len,
sap, sizeof(*sap), net, 0);
if (salen == 0)
continue;
rpc_set_port((struct sockaddr *)sap, NFS_PORT);
error = -ENOMEM;
hostname = kmemdup_nul(buf->data, buf->len, GFP_KERNEL);
if (hostname == NULL)
break;
error = nfs4_update_server(server, hostname, sap, salen, net);
kfree(hostname);
if (error == 0)
break;
}
kfree(sap);
return error;
}
/**
* nfs4_replace_transport - set up transport to destination server
*
* @server: export being migrated
* @locations: fs_locations array
*
* Returns zero on success, or a negative errno value.
*
* The client tries all the entries in the "locations" array, in the
* order returned by the server, until one works or the end of the
* array is reached.
*/
int nfs4_replace_transport(struct nfs_server *server,
const struct nfs4_fs_locations *locations)
{
char *page = NULL, *page2 = NULL;
int loc, error;
error = -ENOENT;
if (locations == NULL || locations->nlocations <= 0)
goto out;
error = -ENOMEM;
page = (char *) __get_free_page(GFP_USER);
if (!page)
goto out;
page2 = (char *) __get_free_page(GFP_USER);
if (!page2)
goto out;
for (loc = 0; loc < locations->nlocations; loc++) {
const struct nfs4_fs_location *location =
&locations->locations[loc];
if (location == NULL || location->nservers <= 0 ||
location->rootpath.ncomponents == 0)
continue;
error = nfs4_try_replacing_one_location(server, page,
page2, location);
if (error == 0)
break;
}
out:
free_page((unsigned long)page);
free_page((unsigned long)page2);
return error;
}