linux/fs/ceph/cache.c
Thomas Gleixner 1f32761322 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 188
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to free software
  foundation 51 franklin street fifth floor boston ma 02111 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 27 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.981318839@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:21 -07:00

350 lines
8.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Ceph cache definitions.
*
* Copyright (C) 2013 by Adfin Solutions, Inc. All Rights Reserved.
* Written by Milosz Tanski (milosz@adfin.com)
*/
#include "super.h"
#include "cache.h"
struct ceph_aux_inode {
u64 version;
u64 mtime_sec;
u64 mtime_nsec;
};
struct fscache_netfs ceph_cache_netfs = {
.name = "ceph",
.version = 0,
};
static DEFINE_MUTEX(ceph_fscache_lock);
static LIST_HEAD(ceph_fscache_list);
struct ceph_fscache_entry {
struct list_head list;
struct fscache_cookie *fscache;
size_t uniq_len;
/* The following members must be last */
struct ceph_fsid fsid;
char uniquifier[0];
};
static const struct fscache_cookie_def ceph_fscache_fsid_object_def = {
.name = "CEPH.fsid",
.type = FSCACHE_COOKIE_TYPE_INDEX,
};
int __init ceph_fscache_register(void)
{
return fscache_register_netfs(&ceph_cache_netfs);
}
void ceph_fscache_unregister(void)
{
fscache_unregister_netfs(&ceph_cache_netfs);
}
int ceph_fscache_register_fs(struct ceph_fs_client* fsc)
{
const struct ceph_fsid *fsid = &fsc->client->fsid;
const char *fscache_uniq = fsc->mount_options->fscache_uniq;
size_t uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
struct ceph_fscache_entry *ent;
int err = 0;
mutex_lock(&ceph_fscache_lock);
list_for_each_entry(ent, &ceph_fscache_list, list) {
if (memcmp(&ent->fsid, fsid, sizeof(*fsid)))
continue;
if (ent->uniq_len != uniq_len)
continue;
if (uniq_len && memcmp(ent->uniquifier, fscache_uniq, uniq_len))
continue;
pr_err("fscache cookie already registered for fsid %pU\n", fsid);
pr_err(" use fsc=%%s mount option to specify a uniquifier\n");
err = -EBUSY;
goto out_unlock;
}
ent = kzalloc(sizeof(*ent) + uniq_len, GFP_KERNEL);
if (!ent) {
err = -ENOMEM;
goto out_unlock;
}
memcpy(&ent->fsid, fsid, sizeof(*fsid));
if (uniq_len > 0) {
memcpy(&ent->uniquifier, fscache_uniq, uniq_len);
ent->uniq_len = uniq_len;
}
fsc->fscache = fscache_acquire_cookie(ceph_cache_netfs.primary_index,
&ceph_fscache_fsid_object_def,
&ent->fsid, sizeof(ent->fsid) + uniq_len,
NULL, 0,
fsc, 0, true);
if (fsc->fscache) {
ent->fscache = fsc->fscache;
list_add_tail(&ent->list, &ceph_fscache_list);
} else {
kfree(ent);
pr_err("unable to register fscache cookie for fsid %pU\n",
fsid);
/* all other fs ignore this error */
}
out_unlock:
mutex_unlock(&ceph_fscache_lock);
return err;
}
static enum fscache_checkaux ceph_fscache_inode_check_aux(
void *cookie_netfs_data, const void *data, uint16_t dlen,
loff_t object_size)
{
struct ceph_aux_inode aux;
struct ceph_inode_info* ci = cookie_netfs_data;
struct inode* inode = &ci->vfs_inode;
if (dlen != sizeof(aux) ||
i_size_read(inode) != object_size)
return FSCACHE_CHECKAUX_OBSOLETE;
memset(&aux, 0, sizeof(aux));
aux.version = ci->i_version;
aux.mtime_sec = inode->i_mtime.tv_sec;
aux.mtime_nsec = inode->i_mtime.tv_nsec;
if (memcmp(data, &aux, sizeof(aux)) != 0)
return FSCACHE_CHECKAUX_OBSOLETE;
dout("ceph inode 0x%p cached okay\n", ci);
return FSCACHE_CHECKAUX_OKAY;
}
static const struct fscache_cookie_def ceph_fscache_inode_object_def = {
.name = "CEPH.inode",
.type = FSCACHE_COOKIE_TYPE_DATAFILE,
.check_aux = ceph_fscache_inode_check_aux,
};
void ceph_fscache_register_inode_cookie(struct inode *inode)
{
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_aux_inode aux;
/* No caching for filesystem */
if (!fsc->fscache)
return;
/* Only cache for regular files that are read only */
if (!S_ISREG(inode->i_mode))
return;
inode_lock_nested(inode, I_MUTEX_CHILD);
if (!ci->fscache) {
memset(&aux, 0, sizeof(aux));
aux.version = ci->i_version;
aux.mtime_sec = inode->i_mtime.tv_sec;
aux.mtime_nsec = inode->i_mtime.tv_nsec;
ci->fscache = fscache_acquire_cookie(fsc->fscache,
&ceph_fscache_inode_object_def,
&ci->i_vino, sizeof(ci->i_vino),
&aux, sizeof(aux),
ci, i_size_read(inode), false);
}
inode_unlock(inode);
}
void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
{
struct fscache_cookie* cookie;
if ((cookie = ci->fscache) == NULL)
return;
ci->fscache = NULL;
fscache_uncache_all_inode_pages(cookie, &ci->vfs_inode);
fscache_relinquish_cookie(cookie, &ci->i_vino, false);
}
static bool ceph_fscache_can_enable(void *data)
{
struct inode *inode = data;
return !inode_is_open_for_write(inode);
}
void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp)
{
struct ceph_inode_info *ci = ceph_inode(inode);
if (!fscache_cookie_valid(ci->fscache))
return;
if (inode_is_open_for_write(inode)) {
dout("fscache_file_set_cookie %p %p disabling cache\n",
inode, filp);
fscache_disable_cookie(ci->fscache, &ci->i_vino, false);
fscache_uncache_all_inode_pages(ci->fscache, inode);
} else {
fscache_enable_cookie(ci->fscache, &ci->i_vino, i_size_read(inode),
ceph_fscache_can_enable, inode);
if (fscache_cookie_enabled(ci->fscache)) {
dout("fscache_file_set_cookie %p %p enabling cache\n",
inode, filp);
}
}
}
static void ceph_readpage_from_fscache_complete(struct page *page, void *data, int error)
{
if (!error)
SetPageUptodate(page);
unlock_page(page);
}
static inline bool cache_valid(struct ceph_inode_info *ci)
{
return ci->i_fscache_gen == ci->i_rdcache_gen;
}
/* Atempt to read from the fscache,
*
* This function is called from the readpage_nounlock context. DO NOT attempt to
* unlock the page here (or in the callback).
*/
int ceph_readpage_from_fscache(struct inode *inode, struct page *page)
{
struct ceph_inode_info *ci = ceph_inode(inode);
int ret;
if (!cache_valid(ci))
return -ENOBUFS;
ret = fscache_read_or_alloc_page(ci->fscache, page,
ceph_readpage_from_fscache_complete, NULL,
GFP_KERNEL);
switch (ret) {
case 0: /* Page found */
dout("page read submitted\n");
return 0;
case -ENOBUFS: /* Pages were not found, and can't be */
case -ENODATA: /* Pages were not found */
dout("page/inode not in cache\n");
return ret;
default:
dout("%s: unknown error ret = %i\n", __func__, ret);
return ret;
}
}
int ceph_readpages_from_fscache(struct inode *inode,
struct address_space *mapping,
struct list_head *pages,
unsigned *nr_pages)
{
struct ceph_inode_info *ci = ceph_inode(inode);
int ret;
if (!cache_valid(ci))
return -ENOBUFS;
ret = fscache_read_or_alloc_pages(ci->fscache, mapping, pages, nr_pages,
ceph_readpage_from_fscache_complete,
NULL, mapping_gfp_mask(mapping));
switch (ret) {
case 0: /* All pages found */
dout("all-page read submitted\n");
return 0;
case -ENOBUFS: /* Some pages were not found, and can't be */
case -ENODATA: /* some pages were not found */
dout("page/inode not in cache\n");
return ret;
default:
dout("%s: unknown error ret = %i\n", __func__, ret);
return ret;
}
}
void ceph_readpage_to_fscache(struct inode *inode, struct page *page)
{
struct ceph_inode_info *ci = ceph_inode(inode);
int ret;
if (!PageFsCache(page))
return;
if (!cache_valid(ci))
return;
ret = fscache_write_page(ci->fscache, page, i_size_read(inode),
GFP_KERNEL);
if (ret)
fscache_uncache_page(ci->fscache, page);
}
void ceph_invalidate_fscache_page(struct inode* inode, struct page *page)
{
struct ceph_inode_info *ci = ceph_inode(inode);
if (!PageFsCache(page))
return;
fscache_wait_on_page_write(ci->fscache, page);
fscache_uncache_page(ci->fscache, page);
}
void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
{
if (fscache_cookie_valid(fsc->fscache)) {
struct ceph_fscache_entry *ent;
bool found = false;
mutex_lock(&ceph_fscache_lock);
list_for_each_entry(ent, &ceph_fscache_list, list) {
if (ent->fscache == fsc->fscache) {
list_del(&ent->list);
kfree(ent);
found = true;
break;
}
}
WARN_ON_ONCE(!found);
mutex_unlock(&ceph_fscache_lock);
__fscache_relinquish_cookie(fsc->fscache, NULL, false);
}
fsc->fscache = NULL;
}
/*
* caller should hold CEPH_CAP_FILE_{RD,CACHE}
*/
void ceph_fscache_revalidate_cookie(struct ceph_inode_info *ci)
{
if (cache_valid(ci))
return;
/* resue i_truncate_mutex. There should be no pending
* truncate while the caller holds CEPH_CAP_FILE_RD */
mutex_lock(&ci->i_truncate_mutex);
if (!cache_valid(ci)) {
if (fscache_check_consistency(ci->fscache, &ci->i_vino))
fscache_invalidate(ci->fscache);
spin_lock(&ci->i_ceph_lock);
ci->i_fscache_gen = ci->i_rdcache_gen;
spin_unlock(&ci->i_ceph_lock);
}
mutex_unlock(&ci->i_truncate_mutex);
}