/* create a cache index for looking up filehandles */
clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
&nfs_fscache_server_index_def,
- clp);
+ clp, true);
dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
clp, clp->fscache);
}
/* create a cache index for looking up filehandles */
nfss->fscache = fscache_acquire_cookie(nfss->nfs_client->fscache,
&nfs_fscache_super_index_def,
- nfss);
+ nfss, true);
dfprintk(FSCACHE, "NFS: get superblock cookie (0x%p/0x%p)\n",
nfss, nfss->fscache);
return;
/*
* Initialise the per-inode cache cookie pointer for an NFS inode.
*/
-void nfs_fscache_init_inode_cookie(struct inode *inode)
+void nfs_fscache_init_inode(struct inode *inode)
{
- NFS_I(inode)->fscache = NULL;
- if (S_ISREG(inode->i_mode))
- set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
-}
-
-/*
- * Get the per-inode cache cookie for an NFS inode.
- */
-static void nfs_fscache_enable_inode_cookie(struct inode *inode)
-{
- struct super_block *sb = inode->i_sb;
struct nfs_inode *nfsi = NFS_I(inode);
- if (nfsi->fscache || !NFS_FSCACHE(inode))
+ nfsi->fscache = NULL;
+ if (!S_ISREG(inode->i_mode))
return;
-
- if ((NFS_SB(sb)->options & NFS_OPTION_FSCACHE)) {
- nfsi->fscache = fscache_acquire_cookie(
- NFS_SB(sb)->fscache,
- &nfs_fscache_inode_object_def,
- nfsi);
-
- dfprintk(FSCACHE, "NFS: get FH cookie (0x%p/0x%p/0x%p)\n",
- sb, nfsi, nfsi->fscache);
- }
+ nfsi->fscache = fscache_acquire_cookie(NFS_SB(inode->i_sb)->fscache,
+ &nfs_fscache_inode_object_def,
+ nfsi, false);
}
/*
* Release a per-inode cookie.
*/
-void nfs_fscache_release_inode_cookie(struct inode *inode)
+void nfs_fscache_clear_inode(struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);
+ struct fscache_cookie *cookie = nfs_i_fscache(inode);
- dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n",
- nfsi, nfsi->fscache);
+ dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n", nfsi, cookie);
- fscache_relinquish_cookie(nfsi->fscache, 0);
+ fscache_relinquish_cookie(cookie, false);
nfsi->fscache = NULL;
}
-/*
- * Retire a per-inode cookie, destroying the data attached to it.
- */
-void nfs_fscache_zap_inode_cookie(struct inode *inode)
+static bool nfs_fscache_can_enable(void *data)
{
- struct nfs_inode *nfsi = NFS_I(inode);
+ struct inode *inode = data;
- dfprintk(FSCACHE, "NFS: zapping cookie (0x%p/0x%p)\n",
- nfsi, nfsi->fscache);
-
- fscache_relinquish_cookie(nfsi->fscache, 1);
- nfsi->fscache = NULL;
+ return !inode_is_open_for_write(inode);
}
/*
- * Turn off the cache with regard to a per-inode cookie if opened for writing,
- * invalidating all the pages in the page cache relating to the associated
- * inode to clear the per-page caching.
- */
-static void nfs_fscache_disable_inode_cookie(struct inode *inode)
-{
- clear_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
-
- if (NFS_I(inode)->fscache) {
- dfprintk(FSCACHE,
- "NFS: nfsi 0x%p turning cache off\n", NFS_I(inode));
-
- /* Need to uncache any pages attached to this inode that
- * fscache knows about before turning off the cache.
- */
- fscache_uncache_all_inode_pages(NFS_I(inode)->fscache, inode);
- nfs_fscache_zap_inode_cookie(inode);
- }
-}
-
-/*
- * wait_on_bit() sleep function for uninterruptible waiting
- */
-static int nfs_fscache_wait_bit(void *flags)
-{
- schedule();
- return 0;
-}
-
-/*
- * Lock against someone else trying to also acquire or relinquish a cookie
- */
-static inline void nfs_fscache_inode_lock(struct inode *inode)
-{
- struct nfs_inode *nfsi = NFS_I(inode);
-
- while (test_and_set_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags))
- wait_on_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK,
- nfs_fscache_wait_bit, TASK_UNINTERRUPTIBLE);
-}
-
-/*
- * Unlock cookie management lock
- */
-static inline void nfs_fscache_inode_unlock(struct inode *inode)
-{
- struct nfs_inode *nfsi = NFS_I(inode);
-
- smp_mb__before_clear_bit();
- clear_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags);
- smp_mb__after_clear_bit();
- wake_up_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK);
-}
-
-/*
- * Decide if we should enable or disable local caching for this inode.
- * - For now, with NFS, only regular files that are open read-only will be able
- * to use the cache.
- * - May be invoked multiple times in parallel by parallel nfs_open() functions.
- */
-void nfs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
-{
- if (NFS_FSCACHE(inode)) {
- nfs_fscache_inode_lock(inode);
- if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
- nfs_fscache_disable_inode_cookie(inode);
- else
- nfs_fscache_enable_inode_cookie(inode);
- nfs_fscache_inode_unlock(inode);
- }
-}
-EXPORT_SYMBOL_GPL(nfs_fscache_set_inode_cookie);
-
-/*
- * Replace a per-inode cookie due to revalidation detecting a file having
- * changed on the server.
+ * Enable or disable caching for a file that is being opened as appropriate.
+ * The cookie is allocated when the inode is initialised, but is not enabled at
+ * that time. Enablement is deferred to file-open time to avoid stat() and
+ * access() thrashing the cache.
+ *
+ * For now, with NFS, only regular files that are open read-only will be able
+ * to use the cache.
+ *
+ * We enable the cache for an inode if we open it read-only and it isn't
+ * currently open for writing. We disable the cache if the inode is open
+ * write-only.
+ *
+ * The caller uses the file struct to pin i_writecount on the inode before
+ * calling us when a file is opened for writing, so we can make use of that.
+ *
+ * Note that this may be invoked multiple times in parallel by parallel
+ * nfs_open() functions.
*/
-void nfs_fscache_reset_inode_cookie(struct inode *inode)
+void nfs_fscache_open_file(struct inode *inode, struct file *filp)
{
struct nfs_inode *nfsi = NFS_I(inode);
- struct nfs_server *nfss = NFS_SERVER(inode);
- NFS_IFDEBUG(struct fscache_cookie *old = nfsi->fscache);
+ struct fscache_cookie *cookie = nfs_i_fscache(inode);
- nfs_fscache_inode_lock(inode);
- if (nfsi->fscache) {
- /* retire the current fscache cache and get a new one */
- fscache_relinquish_cookie(nfsi->fscache, 1);
-
- nfsi->fscache = fscache_acquire_cookie(
- nfss->nfs_client->fscache,
- &nfs_fscache_inode_object_def,
- nfsi);
+ if (!fscache_cookie_valid(cookie))
+ return;
- dfprintk(FSCACHE,
- "NFS: revalidation new cookie (0x%p/0x%p/0x%p/0x%p)\n",
- nfss, nfsi, old, nfsi->fscache);
+ if (inode_is_open_for_write(inode)) {
+ dfprintk(FSCACHE, "NFS: nfsi 0x%p disabling cache\n", nfsi);
+ clear_bit(NFS_INO_FSCACHE, &nfsi->flags);
+ fscache_disable_cookie(cookie, true);
+ fscache_uncache_all_inode_pages(cookie, inode);
+ } else {
+ dfprintk(FSCACHE, "NFS: nfsi 0x%p enabling cache\n", nfsi);
+ fscache_enable_cookie(cookie, nfs_fscache_can_enable, inode);
+ if (fscache_cookie_enabled(cookie))
+ set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
}
- nfs_fscache_inode_unlock(inode);
}
+EXPORT_SYMBOL_GPL(nfs_fscache_open_file);
/*
* Release the caching state associated with a page, if the page isn't busy
int nfs_fscache_release_page(struct page *page, gfp_t gfp)
{
if (PageFsCache(page)) {
- struct nfs_inode *nfsi = NFS_I(page->mapping->host);
- struct fscache_cookie *cookie = nfsi->fscache;
+ struct fscache_cookie *cookie = nfs_i_fscache(page->mapping->host);
BUG_ON(!cookie);
dfprintk(FSCACHE, "NFS: fscache releasepage (0x%p/0x%p/0x%p)\n",
- cookie, page, nfsi);
+ cookie, page, NFS_I(page->mapping->host));
if (!fscache_maybe_release_page(cookie, page, gfp))
return 0;
*/
void __nfs_fscache_invalidate_page(struct page *page, struct inode *inode)
{
- struct nfs_inode *nfsi = NFS_I(inode);
- struct fscache_cookie *cookie = nfsi->fscache;
+ struct fscache_cookie *cookie = nfs_i_fscache(inode);
BUG_ON(!cookie);
dfprintk(FSCACHE, "NFS: fscache invalidatepage (0x%p/0x%p/0x%p)\n",
- cookie, page, nfsi);
+ cookie, page, NFS_I(inode));
fscache_wait_on_page_write(cookie, page);
dfprintk(FSCACHE,
"NFS: readpage_from_fscache(fsc:%p/p:%p(i:%lx f:%lx)/0x%p)\n",
- NFS_I(inode)->fscache, page, page->index, page->flags, inode);
+ nfs_i_fscache(inode), page, page->index, page->flags, inode);
- ret = fscache_read_or_alloc_page(NFS_I(inode)->fscache,
+ ret = fscache_read_or_alloc_page(nfs_i_fscache(inode),
page,
nfs_readpage_from_fscache_complete,
ctx,
int ret;
dfprintk(FSCACHE, "NFS: nfs_getpages_from_fscache (0x%p/%u/0x%p)\n",
- NFS_I(inode)->fscache, npages, inode);
+ nfs_i_fscache(inode), npages, inode);
- ret = fscache_read_or_alloc_pages(NFS_I(inode)->fscache,
+ ret = fscache_read_or_alloc_pages(nfs_i_fscache(inode),
mapping, pages, nr_pages,
nfs_readpage_from_fscache_complete,
ctx,
dfprintk(FSCACHE,
"NFS: readpage_to_fscache(fsc:%p/p:%p(i:%lx f:%lx)/%d)\n",
- NFS_I(inode)->fscache, page, page->index, page->flags, sync);
+ nfs_i_fscache(inode), page, page->index, page->flags, sync);
- ret = fscache_write_page(NFS_I(inode)->fscache, page, GFP_KERNEL);
+ ret = fscache_write_page(nfs_i_fscache(inode), page, GFP_KERNEL);
dfprintk(FSCACHE,
"NFS: readpage_to_fscache: p:%p(i:%lu f:%lx) ret %d\n",
page, page->index, page->flags, ret);
if (ret != 0) {
- fscache_uncache_page(NFS_I(inode)->fscache, page);
+ fscache_uncache_page(nfs_i_fscache(inode), page);
nfs_add_fscache_stats(inode,
NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL, 1);
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_UNCACHED, 1);
projects / karo-tx-linux.git / blobdiff