[PATCH 28/37] NFS: Use local disk inode cache

David Howells
2008-02-08T17:12:41Z

Bind data storage objects in the local cache to NFS inodes.

Signed-off-by: David Howells <dhowells@redhat.com>
---

fs/nfs/fscache.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/fscache.h | 19 +++++++
fs/nfs/inode.c | 39 ++++++++++++--
include/linux/nfs_fs.h | 10 ++++
4 files changed, 193 insertions(+), 6 deletions(-)

diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index cbd09f0..c0e0320 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -166,3 +166,134 @@ void nfs_fscache_release_super_cookie(struct super_block *sb)
nfss->fscache_key = NULL;
}
}
+
+/*
+ * Initialise the per-inode cache cookie pointer for an NFS inode.
+ */
+void nfs_fscache_init_inode_cookie(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.
+ */
+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))
+ return;
+
+ if ((NFS_SB(sb)->options & NFS_OPTION_FSCACHE)) {
+ nfsi->fscache = fscache_acquire_cookie(
+ NFS_SB(sb)->fscache,
+ &nfs_cache_inode_object_def,
+ nfsi);
+
+ dfprintk(FSCACHE, "NFS: get FH cookie (0x%p/0x%p/0x%p)\n",
+ sb, nfsi, nfsi->fscache);
+ }
+}
+
+/*
+ * Release a per-inode cookie.
+ */
+void nfs_fscache_release_inode_cookie(struct inode *inode)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+
+ dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n",
+ nfsi, nfsi->fscache);
+
+ fscache_relinquish_cookie(nfsi->fscache, 0);
+ nfsi->fscache = NULL;
+}
+
+/*
+ * Retire a per-inode cookie, destroying the data attached to it.
+ */
+void nfs_fscache_zap_inode_cookie(struct inode *inode)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+
+ dfprintk(FSCACHE, "NFS: zapping cookie (0x%p/0x%p)\n",
+ nfsi, nfsi->fscache);
+
+ fscache_relinquish_cookie(nfsi->fscache, 1);
+ nfsi->fscache = NULL;
+}
+
+/*
+ * 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.
+ */
+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 invalidate any mapped pages that were read in before
+ * turning off the cache.
+ */
+ if (inode->i_mapping && inode->i_mapping->nrpages)
+ invalidate_inode_pages2(inode->i_mapping);
+
+ nfs_fscache_zap_inode_cookie(inode);
+ }
+}
+
+/*
+ * 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.
+ */
+void nfs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
+{
+ if (NFS_FSCACHE(inode)) {
+ if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
+ nfs_fscache_disable_inode_cookie(inode);
+ else
+ nfs_fscache_enable_inode_cookie(inode);
+ }
+}
+
+/*
+ * Replace a per-inode cookie due to revalidation detecting a file having
+ * changed on the server.
+ */
+void nfs_fscache_renew_inode_cookie(struct inode *inode)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_server *nfss = NFS_SERVER(inode);
+ struct fscache_cookie *old = nfsi->fscache;
+
+ 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_cache_inode_object_def,
+ nfsi);
+
+ dfprintk(FSCACHE,
+ "NFS: revalidation new cookie (0x%p/0x%p/0x%p/0x%p)\n",
+ nfss, nfsi, old, nfsi->fscache);
+ }
+}
+
+/*
+ * Update the filesize associated with a per-inode cookie.
+ */
+void nfs_fscache_attr_changed(struct inode *inode)
+{
+ fscache_attr_changed(NFS_I(inode)->fscache);
+}
diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h
index 7dcdf32..d730ec8 100644
--- a/fs/nfs/fscache.h
+++ b/fs/nfs/fscache.h
@@ -77,6 +77,15 @@ extern void nfs_fscache_get_super_cookie(struct super_block *,
struct nfs_parsed_mount_data *);
extern void nfs_fscache_release_super_cookie(struct super_block *);

+extern void nfs_fscache_init_inode_cookie(struct inode *);
+extern void nfs_fscache_enable_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_disable_inode_cookie(struct inode *);
+extern void nfs_fscache_set_inode_cookie(struct inode *, struct file *);
+extern void nfs_fscache_renew_inode_cookie(struct inode *);
+extern void nfs_fscache_attr_changed(struct inode *);
+
#else /* CONFIG_NFS_FSCACHE */
static inline int nfs_fscache_register(void) { return 0; }
static inline void nfs_fscache_unregister(void) {}
@@ -91,5 +100,15 @@ static inline void nfs_fscache_get_super_cookie(
}
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_enable_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_renew_inode_cookie(struct inode *inode) {}
+static inline void nfs_fscache_disable_inode_cookie(struct inode *inode) {}
+static inline void nfs_fscache_set_inode_cookie(struct inode *inode,
+ struct file *filp) {}
+static inline void nfs_fscache_attr_changed(struct inode *inode) {}
+
#endif /* CONFIG_NFS_FSCACHE */
#endif /* _NFS_FSCACHE_H */
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 7254d5c..eafad13 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -112,6 +112,7 @@ void nfs_clear_inode(struct inode *inode)
BUG_ON(!list_empty(&NFS_I(inode)->open_files));
nfs_zap_acl_cache(inode);
nfs_access_zap_cache(inode);
+ nfs_fscache_release_inode_cookie(inode);
}

/**
@@ -331,6 +332,8 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
nfsi->access_cache = RB_ROOT;

+ nfs_fscache_init_inode_cookie(inode);
+
unlock_new_inode(inode);
} else
nfs_refresh_inode(inode, fattr);
@@ -619,6 +622,7 @@ int nfs_open(struct inode *inode, struct file *filp)
ctx->mode = filp->f_mode;
nfs_file_set_open_context(filp, ctx);
put_nfs_open_context(ctx);
+ nfs_fscache_set_inode_cookie(inode, filp);
return 0;
}

@@ -679,7 +683,13 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
(long long)NFS_FILEID(inode), status);
goto out;
}
- spin_unlock(&inode->i_lock);
+ if (nfsi->cache_validity & NFS_INO_INVALID_FSCACHE_ATTR) {
+ nfsi->cache_validity &= ~NFS_INO_INVALID_FSCACHE_ATTR;
+ spin_unlock(&inode->i_lock);
+ nfs_fscache_attr_changed(inode);
+ } else {
+ spin_unlock(&inode->i_lock);
+ }

if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
nfs_zap_acl_cache(inode);
@@ -735,6 +745,7 @@ static int nfs_invalidate_mapping_nolock(struct inode *inode, struct address_spa
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
spin_unlock(&inode->i_lock);
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
+ nfs_fscache_renew_inode_cookie(inode);
dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
inode->i_sb->s_id, (long long)NFS_FILEID(inode));
return 0;
@@ -911,7 +922,13 @@ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
else
status = nfs_check_inode_attributes(inode, fattr);

- spin_unlock(&inode->i_lock);
+ if (nfsi->cache_validity & NFS_INO_INVALID_FSCACHE_ATTR) {
+ nfsi->cache_validity &= ~NFS_INO_INVALID_FSCACHE_ATTR;
+ spin_unlock(&inode->i_lock);
+ nfs_fscache_attr_changed(inode);
+ } else {
+ spin_unlock(&inode->i_lock);
+ }
return status;
}

@@ -932,12 +949,19 @@ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
+ bool update_fscache = false;

spin_lock(&inode->i_lock);
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+ if (nfsi->cache_validity & NFS_INO_INVALID_FSCACHE_ATTR) {
+ nfsi->cache_validity &= ~NFS_INO_INVALID_FSCACHE_ATTR;
+ update_fscache = true;
+ }
spin_unlock(&inode->i_lock);
+ if (update_fscache)
+ nfs_fscache_attr_changed(inode);
return nfs_refresh_inode(inode, fattr);
}

@@ -1025,7 +1049,8 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
if (!timespec_equal(&inode->i_mtime, &fattr->mtime)) {
dprintk("NFS: mtime change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
- invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
+ invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA |
+ NFS_INO_INVALID_FSCACHE_ATTR;
if (S_ISDIR(inode->i_mode))
nfs_force_lookup_revalidate(inode);
}
@@ -1035,7 +1060,9 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
} else if (nfsi->change_attr != fattr->change_attr) {
dprintk("NFS: change_attr change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
- invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+ invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA |
+ NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL |
+ NFS_INO_INVALID_FSCACHE_ATTR;
if (S_ISDIR(inode->i_mode))
nfs_force_lookup_revalidate(inode);
}
@@ -1048,13 +1075,13 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
* the file grown beyond our last write? */
if (nfsi->npages == 0 || new_isize > cur_isize) {
inode->i_size = new_isize;
- invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
+ invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA |
+ NFS_INO_INVALID_FSCACHE_ATTR;
}
dprintk("NFS: isize change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
}

-
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 14894c9..d9adb53 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -174,6 +174,9 @@ struct nfs_inode {
int delegation_state;
struct rw_semaphore rwsem;
#endif /* CONFIG_NFS_V4*/
+#ifdef CONFIG_NFS_FSCACHE
+ struct fscache_cookie *fscache;
+#endif
struct inode vfs_inode;
};

@@ -187,6 +190,7 @@ struct nfs_inode {
#define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
#define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */
#define NFS_INO_REVAL_FORCED 0x0040 /* force revalidation ignoring a delegation */
+#define NFS_INO_INVALID_FSCACHE_ATTR 0x0080 /* local cache attributes are invalid */

/*
* Bit offsets in flags field
@@ -195,6 +199,7 @@ struct nfs_inode {
#define NFS_INO_ADVISE_RDPLUS (1) /* advise readdirplus */
#define NFS_INO_STALE (2) /* possible stale inode */
#define NFS_INO_ACL_LRU_SET (3) /* Inode is on the LRU list */
+#define NFS_INO_FSCACHE (4) /* inode can be cached by FS-Cache */

static inline struct nfs_inode *NFS_I(const struct inode *inode)
{
@@ -248,6 +253,11 @@ 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)
+{
+ return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
+}
+
static inline __u64 NFS_FILEID(const struct inode *inode)
{
return NFS_I(inode)->fileid;