The fact that the lookup revalidation failed, does not mean that the
inode contents have changed.
Fixes: 5ceb9d7fda ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
There should be no reason to expect the directory permissions to change
just because the directory contents changed or a negative lookup timed
out. So let's avoid doing a full call to nfs_mark_for_revalidate() in
that case.
Furthermore, if this is a negative dentry, and we haven't actually done
a new lookup, then we have no reason yet to believe the directory has
changed at all. So let's remove the gratuitous directory inode
invalidation altogether when called from
nfs_lookup_revalidate_negative().
Reported-by: Geert Jansen <gerardu@amazon.com>
Fixes: 5ceb9d7fda ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Highlights include:
Features:
- NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
support.
- A series of patches to improve readdir performance, particularly with
large directories.
- Basic support for using NFS/RDMA with the pNFS files and flexfiles
drivers.
- Micro-optimisations for RDMA.
- RDMA tracing improvements.
Bugfixes:
- Fix a long standing bug with xs_read_xdr_buf() when receiving partial
pages (Dan Aloni).
- Various fixes for getxattr and listxattr, when used over non-TCP
transports.
- Fixes for containerised NFS from Sargun Dhillon.
- switch nfsiod to be an UNBOUND workqueue (Neil Brown).
- READDIR should not ask for security label information if there is no
LSM policy. (Olga Kornievskaia)
- Avoid using interval-based rebinding with TCP in lockd (Calum Mackay).
- A series of RPC and NFS layer fixes to support the NFSv4.2 READ_PLUS code.
- A couple of fixes for pnfs/flexfiles read failover
Cleanups:
- Various cleanups for the SUNRPC xdr code in conjunction with the
READ_PLUS fixes.
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Merge tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
support
- A series of patches to improve readdir performance, particularly
with large directories
- Basic support for using NFS/RDMA with the pNFS files and flexfiles
drivers
- Micro-optimisations for RDMA
- RDMA tracing improvements
Bugfixes:
- Fix a long standing bug with xs_read_xdr_buf() when receiving
partial pages (Dan Aloni)
- Various fixes for getxattr and listxattr, when used over non-TCP
transports
- Fixes for containerised NFS from Sargun Dhillon
- switch nfsiod to be an UNBOUND workqueue (Neil Brown)
- READDIR should not ask for security label information if there is
no LSM policy (Olga Kornievskaia)
- Avoid using interval-based rebinding with TCP in lockd (Calum
Mackay)
- A series of RPC and NFS layer fixes to support the NFSv4.2
READ_PLUS code
- A couple of fixes for pnfs/flexfiles read failover
Cleanups:
- Various cleanups for the SUNRPC xdr code in conjunction with the
READ_PLUS fixes"
* tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (90 commits)
NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
NFSv4/pnfs: Add tracing for the deviceid cache
fs/lockd: convert comma to semicolon
NFSv4.2: fix error return on memory allocation failure
NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
NFSv4.2: decode_read_plus_hole() needs to check the extent offset
NFSv4.2: decode_read_plus_data() must skip padding after data segment
NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
SUNRPC: When expanding the buffer, we may need grow the sparse pages
SUNRPC: Cleanup - constify a number of xdr_buf helpers
SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field
SUNRPC: _copy_to/from_pages() now check for zero length
SUNRPC: Cleanup xdr_shrink_bufhead()
SUNRPC: Fix xdr_expand_hole()
SUNRPC: Fixes for xdr_align_data()
SUNRPC: _shift_data_left/right_pages should check the shift length
...
If the directory is changing, causing the page cache to get invalidated
while we are listing the contents, then the NFS client is currently forced
to read in the entire directory contents from scratch, because it needs
to perform a linear search for the readdir cookie. While this is not
an issue for small directories, it does not scale to directories with
millions of entries.
In order to be able to deal with large directories that are changing,
add a heuristic to ensure that if the page cache is empty, and we are
searching for a cookie that is not the zero cookie, we just default to
performing uncached readdir.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If we're doing uncached readdir, allocate multiple pages in order to
try to avoid duplicate RPC calls for the same getdents() call.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If the server is handing out monotonically increasing readdir cookie values,
then we can optimise away searches through pages that contain cookies that
lie outside our search range.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If the server insists on using the readdir verifiers in order to allow
cookies to expire, then we should ensure that we cache the verifier
with the cookie, so that we can return an error if the application
tries to use the expired cookie.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If the server returns NFS4ERR_NOT_SAME or tells us that the cookie is
bad in response to a READDIR call, then we should empty the page cache
so that we can fill it from scratch again.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If we're ever going to allow support for servers that use the readdir
verifier, then that use needs to be managed by the middle layers as
those need to be able to reject cookies from other verifiers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
The descriptor and the struct nfs_entry are both large structures,
so don't allocate them from the stack.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Clean up nfs_do_filldir().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Remove the redundant caching of the credential in struct
nfs_open_dir_context.
Pass the buffer size as an argument to nfs_readdir_xdr_filler().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Support readdir buffers of up to 1MB in size so that we can read
large directories using few RPC calls.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
We don't need to store a hash, so replace struct qstr with a simple
const char pointer and length.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
The kmapped pointer is only used once per loop to check if we need to
exit.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
If a readdir call returns more data than we can fit into one page
cache page, then allocate a new one for that data rather than
discarding the data.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Refactor to use pagecache_get_page() so that we can fill the page
in multiple stages.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Clean up handling of the case where there are no entries in the readdir
reply.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Since the 'eof_index' is only ever used as a flag, make it so.
Also add a flag to detect if the page has been completely filled.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Ensure that the contents of struct nfs_open_dir_context are consistent
by setting them under the file->f_lock from a private copy (that is
known to be consistent).
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
nfs_inc_stats() is already thread-safe, and there are no other reasons
to hold the inode lock here.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Remove the contentious inode lock, and instead provide thread safety
using the file->f_lock spinlock.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
nfs_readdir_page_filler() iterates over entries in a directory, reusing
the same security label buffer, but does not reset the buffer's length.
This causes decode_attr_security_label() to return -ERANGE if an entry's
security label is longer than the previous one's. This error, in
nfs4_decode_dirent(), only gets passed up as -EAGAIN, which causes another
failed attempt to copy into the buffer. The second error is ignored and
the remaining entries do not show up in ls, specifically the getdents64()
syscall.
Reproduce by creating multiple files in NFS and giving one of the later
files a longer security label. ls will not see that file nor any that are
added afterwards, though they will exist on the backend.
In nfs_readdir_page_filler(), reset security label buffer length before
every reuse
Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io>
Fixes: b4487b9354 ("nfs: Fix getxattr kernel panic and memory overflow")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
RFC 8276 defines separate ACCESS bits for extended attribute checking.
Query them in nfs_do_access and opendata.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The only consumer of nfs_access_get_cached_rcu and nfs_access_cached
calls these static functions in order to first try RCU access, and
then locked access.
Combine them in to a single function, and call that. Make this function
available to the rest of the NFS code.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Stable fixes:
- Fix a page leak in nfs_destroy_unlinked_subrequests()
- Fix use-after-free issues in nfs_pageio_add_request()
- Fix new mount code constant_table array definitions
- finish_automount() requires us to hold 2 refs to the mount record
Features:
- Improve the accuracy of telldir/seekdir by using 64-bit cookies when
possible.
- Allow one RDMA active connection and several zombie connections to
prevent blocking if the remote server is unresponsive.
- Limit the size of the NFS access cache by default
- Reduce the number of references to credentials that are taken by NFS
- pNFS files and flexfiles drivers now support per-layout segment
COMMIT lists.
- Enable partial-file layout segments in the pNFS/flexfiles driver.
- Add support for CB_RECALL_ANY to the pNFS flexfiles layout type
- pNFS/flexfiles Report NFS4ERR_DELAY and NFS4ERR_GRACE errors from
the DS using the layouterror mechanism.
Bugfixes and cleanups:
- SUNRPC: Fix krb5p regressions
- Don't specify NFS version in "UDP not supported" error
- nfsroot: set tcp as the default transport protocol
- pnfs: Return valid stateids in nfs_layout_find_inode_by_stateid()
- alloc_nfs_open_context() must use the file cred when available
- Fix locking when dereferencing the delegation cred
- Fix memory leaks in O_DIRECT when nfs_get_lock_context() fails
- Various clean ups of the NFS O_DIRECT commit code
- Clean up RDMA connect/disconnect
- Replace zero-length arrays with C99-style flexible arrays
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Merge tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Fix a page leak in nfs_destroy_unlinked_subrequests()
- Fix use-after-free issues in nfs_pageio_add_request()
- Fix new mount code constant_table array definitions
- finish_automount() requires us to hold 2 refs to the mount record
Features:
- Improve the accuracy of telldir/seekdir by using 64-bit cookies
when possible.
- Allow one RDMA active connection and several zombie connections to
prevent blocking if the remote server is unresponsive.
- Limit the size of the NFS access cache by default
- Reduce the number of references to credentials that are taken by
NFS
- pNFS files and flexfiles drivers now support per-layout segment
COMMIT lists.
- Enable partial-file layout segments in the pNFS/flexfiles driver.
- Add support for CB_RECALL_ANY to the pNFS flexfiles layout type
- pNFS/flexfiles Report NFS4ERR_DELAY and NFS4ERR_GRACE errors from
the DS using the layouterror mechanism.
Bugfixes and cleanups:
- SUNRPC: Fix krb5p regressions
- Don't specify NFS version in "UDP not supported" error
- nfsroot: set tcp as the default transport protocol
- pnfs: Return valid stateids in nfs_layout_find_inode_by_stateid()
- alloc_nfs_open_context() must use the file cred when available
- Fix locking when dereferencing the delegation cred
- Fix memory leaks in O_DIRECT when nfs_get_lock_context() fails
- Various clean ups of the NFS O_DIRECT commit code
- Clean up RDMA connect/disconnect
- Replace zero-length arrays with C99-style flexible arrays"
* tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (86 commits)
NFS: Clean up process of marking inode stale.
SUNRPC: Don't start a timer on an already queued rpc task
NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()
NFS/pnfs: Fix dereference of layout cred in pnfs_layoutcommit_inode()
NFS: Beware when dereferencing the delegation cred
NFS: Add a module parameter to set nfs_mountpoint_expiry_timeout
NFS: finish_automount() requires us to hold 2 refs to the mount record
NFS: Fix a few constant_table array definitions
NFS: Try to join page groups before an O_DIRECT retransmission
NFS: Refactor nfs_lock_and_join_requests()
NFS: Reverse the submission order of requests in __nfs_pageio_add_request()
NFS: Clean up nfs_lock_and_join_requests()
NFS: Remove the redundant function nfs_pgio_has_mirroring()
NFS: Fix memory leaks in nfs_pageio_stop_mirroring()
NFS: Fix a request reference leak in nfs_direct_write_clear_reqs()
NFS: Fix use-after-free issues in nfs_pageio_add_request()
NFS: Fix races nfs_page_group_destroy() vs nfs_destroy_unlinked_subrequests()
NFS: Fix a page leak in nfs_destroy_unlinked_subrequests()
NFS: Remove unused FLUSH_SYNC support in nfs_initiate_pgio()
pNFS/flexfiles: Specify the layout segment range in LAYOUTGET
...
Instead of the various open coded calls to set the NFS_INO_STALE bit
and call nfs_zap_caches(), consolidate them into a single function
nfs_set_inode_stale().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Pull RCU changes from Paul E. McKenney:
- Make kfree_rcu() use kfree_bulk() for added performance
- RCU updates
- Callback-overload handling updates
- Tasks-RCU KCSAN and sparse updates
- Locking torture test and RCU torture test updates
- Documentation updates
- Miscellaneous fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In function nfs_permission:
1. the rcu_read_lock and rcu_read_unlock around nfs_do_access
is unnecessary because the rcu critical data structure is already
protected in subsidiary function nfs_access_get_cached_rcu. No other
data structure needs rcu_read_lock in nfs_do_access.
2. call nfs_do_access once is enough, because:
2-1. when mask has MAY_NOT_BLOCK bit
The second call to nfs_do_access will not happen.
2-2. when mask has no MAY_NOT_BLOCK bit
The second call to nfs_do_access will happen if res == -ECHILD, which
means the first nfs_do_access goes out after statement if (!may_block).
The second call to nfs_do_access will go through this procedure once
again except continue the work after if (!may_block).
But above work can be performed by only one call to nfs_do_access
without mangling the mask flag.
Tested in x86_64
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Currently, we have no real limit on the access cache size (we set it
to ULONG_MAX). That can lead to credentials getting pinned for a
very long time on lots of files if you have a system with a lot of
memory.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we're running as a 64-bit architecture and are not running in
32-bit compatibility mode, it is better to use the 64-bit readdir
cookies that supplied by the server. Doing so improves the accuracy
of telldir()/seekdir(), particularly when the directory is changing,
for instance, when doing 'rm -rf'.
We still fall back to using the 32-bit offsets on 32-bit architectures
and when in compatibility mode.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If a dentry was not initially looked up while we were holding a
delegation, then we do still need to revalidate that it still holds
the same name. If there are multiple hard links to the same file,
then all the hard links need validation.
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
[Anna: Put nfs_unset_verifier_delegated() under CONFIG_NFS_V4]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In order to avoid having our dentry revalidation race with an update
of the directory on the server, we need to store the verifier before
the RPC calls to LOOKUP and READDIR.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@gmail.com>
Tested-by: Benjamin Coddington <bcodding@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When the directory is large and it's being modified by one client
while another client is doing the 'ls -l' on the same directory then
the cache page invalidation from nfs_force_use_readdirplus causes
the reading client to keep restarting READDIRPLUS from cookie 0
which causes the 'ls -l' to take a very long time to complete,
possibly never completing.
Currently when nfs_force_use_readdirplus is called to switch from
READDIR to READDIRPLUS, it invalidates all the cached pages of the
directory. This cache page invalidation causes the next nfs_readdir
to re-read the directory content from cookie 0.
This patch is to optimise the cache invalidation in
nfs_force_use_readdirplus by only truncating the cached pages from
last page index accessed to the end the file. It also marks the
inode to delay invalidating all the cached page of the directory
until the next initial nfs_readdir of the next 'ls' instance.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Trond Myklebust <trond.myklebust@hammerspace.com>
[Anna - Fix conflicts with Trond's readdir patches]
[Anna - Remove redundant call to nfs_zap_mapping()]
[Anna - Replace d_inode(file_dentry(desc->file)) with file_inode(desc->file)]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Now that the page cache locking is repaired, we should be able to
switch to using iterate_shared() for improved concurrency when
doing readdir().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The directory strings stored in the readdir cache may be used with
printk(), so it is better to ensure they are nul-terminated.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When a NFS directory page cache page is removed from the page cache,
its contents are freed through a call to nfs_readdir_clear_array().
To prevent the removal of the page cache entry until after we've
finished reading it, we must take the page lock.
Fixes: 11de3b11e0 ("NFS: Fix a memory leak in nfs_readdir")
Cc: stable@vger.kernel.org # v2.6.37+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
nfs_readdir_xdr_to_array() must not exit without having initialised
the array, so that the page cache deletion routines can safely
call nfs_readdir_clear_array().
Furthermore, we should ensure that if we exit nfs_readdir_filler()
with an error, we free up any page contents to prevent a leak
if we try to fill the page again.
Fixes: 11de3b11e0 ("NFS: Fix a memory leak in nfs_readdir")
Cc: stable@vger.kernel.org # v2.6.37+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We do not need to have the rcu lookup method fail in the case where
the fsuid/fsgid and supplemental groups match.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the server is unavaliable, we want to allow the revalidating
lookup to time out, and to default to validating the cached dentry
if the 'softreval' mount option is set.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we've already revalidated the inode once then don't distrust the
access cache unless the NFS_INO_INVALID_ACCESS flag is actually set.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
On exit from nfs_do_access(), record the mask representing the requested
permissions, as well as the server-supplied set of access rights for
this user.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
