diff options
| -rw-r--r-- | fs/nfs/dir.c | 2 | ||||
| -rw-r--r-- | fs/nfs/fscache.c | 198 | ||||
| -rw-r--r-- | fs/nfs/fscache.h | 18 | ||||
| -rw-r--r-- | fs/nfs/inode.c | 6 | ||||
| -rw-r--r-- | fs/nfs/nfs4file.c | 2 | ||||
| -rw-r--r-- | include/linux/fs.h | 5 | ||||
| -rw-r--r-- | include/linux/nfs_fs.h | 8 |
7 files changed, 79 insertions, 160 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 854a8f0..4c5edcc 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1381,7 +1381,7 @@ static struct nfs_open_context *create_nfs_open_context(struct dentry *dentry, i static int do_open(struct inode *inode, struct file *filp) { - nfs_fscache_set_inode_cookie(inode, filp); + nfs_fscache_open_file(inode, filp); return 0; } diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c index cd6e7ef..3ef01f0 100644 --- a/fs/nfs/fscache.c +++ b/fs/nfs/fscache.c @@ -178,163 +178,79 @@ void nfs_fscache_release_super_cookie(struct super_block *sb) /* * 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, true); - - 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, true); + 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 @@ -344,12 +260,11 @@ void nfs_fscache_reset_inode_cookie(struct inode *inode) 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; @@ -367,13 +282,12 @@ int nfs_fscache_release_page(struct page *page, gfp_t gfp) */ 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); @@ -417,9 +331,9 @@ int __nfs_readpage_from_fscache(struct nfs_open_context *ctx, 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, @@ -459,9 +373,9 @@ int __nfs_readpages_from_fscache(struct nfs_open_context *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, @@ -506,15 +420,15 @@ void __nfs_readpage_to_fscache(struct inode *inode, struct page *page, int sync) 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); diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h index 4ecb766..d7fe3e7 100644 --- a/fs/nfs/fscache.h +++ b/fs/nfs/fscache.h @@ -76,11 +76,9 @@ extern void nfs_fscache_release_client_cookie(struct nfs_client *); extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int); extern void nfs_fscache_release_super_cookie(struct super_block *); -extern void nfs_fscache_init_inode_cookie(struct inode *); -extern void nfs_fscache_release_inode_cookie(struct inode *); -extern void nfs_fscache_zap_inode_cookie(struct inode *); -extern void nfs_fscache_set_inode_cookie(struct inode *, struct file *); -extern void nfs_fscache_reset_inode_cookie(struct inode *); +extern void nfs_fscache_init_inode(struct inode *); +extern void nfs_fscache_clear_inode(struct inode *); +extern void nfs_fscache_open_file(struct inode *, struct file *); extern void __nfs_fscache_invalidate_page(struct page *, struct inode *); extern int nfs_fscache_release_page(struct page *, gfp_t); @@ -187,12 +185,10 @@ static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {} static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {} -static inline void nfs_fscache_init_inode_cookie(struct inode *inode) {} -static inline void nfs_fscache_release_inode_cookie(struct inode *inode) {} -static inline void nfs_fscache_zap_inode_cookie(struct inode *inode) {} -static inline void nfs_fscache_set_inode_cookie(struct inode *inode, - struct file *filp) {} -static inline void nfs_fscache_reset_inode_cookie(struct inode *inode) {} +static inline void nfs_fscache_init_inode(struct inode *inode) {} +static inline void nfs_fscache_clear_inode(struct inode *inode) {} +static inline void nfs_fscache_open_file(struct inode *inode, + struct file *filp) {} static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp) { diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index eda8879..bb90bff 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -122,7 +122,7 @@ void nfs_clear_inode(struct inode *inode) WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files)); nfs_zap_acl_cache(inode); nfs_access_zap_cache(inode); - nfs_fscache_release_inode_cookie(inode); + nfs_fscache_clear_inode(inode); } EXPORT_SYMBOL_GPL(nfs_clear_inode); @@ -459,7 +459,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st nfsi->attrtimeo_timestamp = now; nfsi->access_cache = RB_ROOT; - nfs_fscache_init_inode_cookie(inode); + nfs_fscache_init_inode(inode); unlock_new_inode(inode); } else @@ -854,7 +854,7 @@ int nfs_open(struct inode *inode, struct file *filp) return PTR_ERR(ctx); nfs_file_set_open_context(filp, ctx); put_nfs_open_context(ctx); - nfs_fscache_set_inode_cookie(inode, filp); + nfs_fscache_open_file(inode, filp); return 0; } diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index e5b804d..5b8a618 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -74,7 +74,7 @@ nfs4_file_open(struct inode *inode, struct file *filp) nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); nfs_file_set_open_context(filp, ctx); - nfs_fscache_set_inode_cookie(inode, filp); + nfs_fscache_open_file(inode, filp); err = 0; out_put_ctx: diff --git a/include/linux/fs.h b/include/linux/fs.h index 3f40547..955dff5 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2292,6 +2292,11 @@ static inline void allow_write_access(struct file *file) if (file) atomic_inc(&file_inode(file)->i_writecount); } +static inline bool inode_is_open_for_write(const struct inode *inode) +{ + return atomic_read(&inode->i_writecount) > 0; +} + #ifdef CONFIG_IMA static inline void i_readcount_dec(struct inode *inode) { diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index 3ea4cde..14a4820 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -269,9 +269,13 @@ static inline int NFS_STALE(const struct inode *inode) return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags); } -static inline int NFS_FSCACHE(const struct inode *inode) +static inline struct fscache_cookie *nfs_i_fscache(struct inode *inode) { - return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags); +#ifdef CONFIG_NFS_FSCACHE + return NFS_I(inode)->fscache; +#else + return NULL; +#endif } static inline __u64 NFS_FILEID(const struct inode *inode) |
