From 717d44e849219781ced028a40fcc59d3e1f49e4c Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Wed, 24 Jan 2007 11:54:55 -0800 Subject: [PATCH] NFS: Fix races in nfs_revalidate_mapping() Prevent the call to invalidate_inode_pages2() from racing with file writes by taking the inode->i_mutex across the page cache flush and invalidate. Signed-off-by: Trond Myklebust Signed-off-by: Linus Torvalds --- fs/nfs/dir.c | 2 +- fs/nfs/inode.c | 97 ++++++++++++++++++++++++++++++++++++++------------------ fs/nfs/symlink.c | 4 ++- 3 files changed, 71 insertions(+), 32 deletions(-) (limited to 'fs/nfs') diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index dee3d6c0f194..d9ba8cb0ee75 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -532,7 +532,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir) lock_kernel(); - res = nfs_revalidate_mapping(inode, filp->f_mapping); + res = nfs_revalidate_mapping_nolock(inode, filp->f_mapping); if (res < 0) { unlock_kernel(); return res; diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 63e470279309..d83498282837 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -665,49 +665,86 @@ int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode) return __nfs_revalidate_inode(server, inode); } +static int nfs_invalidate_mapping_nolock(struct inode *inode, struct address_space *mapping) +{ + struct nfs_inode *nfsi = NFS_I(inode); + + if (mapping->nrpages != 0) { + int ret = invalidate_inode_pages2(mapping); + if (ret < 0) + return ret; + } + spin_lock(&inode->i_lock); + nfsi->cache_validity &= ~NFS_INO_INVALID_DATA; + if (S_ISDIR(inode->i_mode)) { + memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf)); + /* This ensures we revalidate child dentries */ + nfsi->cache_change_attribute = jiffies; + } + spin_unlock(&inode->i_lock); + nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE); + dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n", + inode->i_sb->s_id, (long long)NFS_FILEID(inode)); + return 0; +} + +static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping) +{ + int ret = 0; + + mutex_lock(&inode->i_mutex); + if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_DATA) { + ret = nfs_sync_mapping(mapping); + if (ret == 0) + ret = nfs_invalidate_mapping_nolock(inode, mapping); + } + mutex_unlock(&inode->i_mutex); + return ret; +} + /** - * nfs_revalidate_mapping - Revalidate the pagecache + * nfs_revalidate_mapping_nolock - Revalidate the pagecache * @inode - pointer to host inode * @mapping - pointer to mapping */ -int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping) +int nfs_revalidate_mapping_nolock(struct inode *inode, struct address_space *mapping) { struct nfs_inode *nfsi = NFS_I(inode); int ret = 0; - if (NFS_STALE(inode)) - ret = -ESTALE; if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) - || nfs_attribute_timeout(inode)) + || nfs_attribute_timeout(inode) || NFS_STALE(inode)) { ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode); - if (ret < 0) - goto out; + if (ret < 0) + goto out; + } + if (nfsi->cache_validity & NFS_INO_INVALID_DATA) + ret = nfs_invalidate_mapping_nolock(inode, mapping); +out: + return ret; +} - if (nfsi->cache_validity & NFS_INO_INVALID_DATA) { - if (mapping->nrpages != 0) { - if (S_ISREG(inode->i_mode)) { - ret = nfs_sync_mapping(mapping); - if (ret < 0) - goto out; - } - ret = invalidate_inode_pages2(mapping); - if (ret < 0) - goto out; - } - spin_lock(&inode->i_lock); - nfsi->cache_validity &= ~NFS_INO_INVALID_DATA; - if (S_ISDIR(inode->i_mode)) { - memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf)); - /* This ensures we revalidate child dentries */ - nfsi->cache_change_attribute = jiffies; - } - spin_unlock(&inode->i_lock); +/** + * nfs_revalidate_mapping - Revalidate the pagecache + * @inode - pointer to host inode + * @mapping - pointer to mapping + * + * This version of the function will take the inode->i_mutex and attempt to + * flush out all dirty data if it needs to invalidate the page cache. + */ +int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping) +{ + struct nfs_inode *nfsi = NFS_I(inode); + int ret = 0; - nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE); - dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n", - inode->i_sb->s_id, - (long long)NFS_FILEID(inode)); + if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) + || nfs_attribute_timeout(inode) || NFS_STALE(inode)) { + ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode); + if (ret < 0) + goto out; } + if (nfsi->cache_validity & NFS_INO_INVALID_DATA) + ret = nfs_invalidate_mapping(inode, mapping); out: return ret; } diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c index 6c686112cc03..525c136c7d8c 100644 --- a/fs/nfs/symlink.c +++ b/fs/nfs/symlink.c @@ -50,7 +50,9 @@ static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd) { struct inode *inode = dentry->d_inode; struct page *page; - void *err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping)); + void *err; + + err = ERR_PTR(nfs_revalidate_mapping_nolock(inode, inode->i_mapping)); if (err) goto read_failed; page = read_cache_page(&inode->i_data, 0, -- cgit v1.2.3 From 46bae1a9a767f3ae8e636d96f9b95703df34b398 Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Tue, 30 Jan 2007 14:36:01 -0800 Subject: [PATCH] Remove warning: VFS is out of sync with lock manager But keep it as a dprintk The message can be generated in a quite normal situation: If a 'lock' request is interrupted, then the lock client needs to record that the server has the lock, incase it does. When we come the unlock, the server might say it doesn't, even though we think it does (or might) and this generates the message. Signed-off-by: Neil Brown Acked-by: Trond Myklebust Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nfs/file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'fs/nfs') diff --git a/fs/nfs/file.c b/fs/nfs/file.c index fab20d06d936..9e4a2b70995a 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -434,8 +434,9 @@ static int do_vfs_lock(struct file *file, struct file_lock *fl) BUG(); } if (res < 0) - printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n", - __FUNCTION__); + dprintk(KERN_WARNING "%s: VFS is out of sync with lock manager" + " - error %d!\n", + __FUNCTION__, res); return res; } -- cgit v1.2.3