diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 90f292b520d..404c19c866a 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -354,6 +354,15 @@ static int nfs_write_begin(struct file *file, struct address_space *mapping, file->f_path.dentry->d_name.name, mapping->host->i_ino, len, (long long) pos); + /* + * Prevent starvation issues if someone is doing a consistency + * sync-to-disk + */ + ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING, + nfs_wait_bit_killable, TASK_KILLABLE); + if (ret) + return ret; + page = grab_cache_page_write_begin(mapping, index, flags); if (!page) return -ENOMEM; diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 00f116cdadc..c40adc5dd60 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -65,6 +65,18 @@ nfs_fattr_to_ino_t(struct nfs_fattr *fattr) return nfs_fileid_to_ino_t(fattr->fileid); } +/** + * nfs_wait_bit_killable - helper for functions that are sleeping on bit locks + * @word: long word containing the bit lock + */ +int nfs_wait_bit_killable(void *word) +{ + if (fatal_signal_pending(current)) + return -ERESTARTSYS; + schedule(); + return 0; +} + /** * nfs_compat_user_ino64 - returns the user-visible inode number * @fileid: 64-bit fileid diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 340ede8f608..a55e69aa52e 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -165,6 +165,7 @@ extern void nfs_clear_inode(struct inode *); extern void nfs4_clear_inode(struct inode *); #endif void nfs_zap_acl_cache(struct inode *inode); +extern int nfs_wait_bit_killable(void *word); /* super.c */ void nfs_parse_ip_address(char *, size_t, struct sockaddr *, size_t *); diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 101f5f4c304..95f171e7e05 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -193,14 +193,6 @@ static void nfs4_setup_readdir(u64 cookie, __be32 *verifier, struct dentry *dent kunmap_atomic(start, KM_USER0); } -static int nfs4_wait_bit_killable(void *word) -{ - if (fatal_signal_pending(current)) - return -ERESTARTSYS; - schedule(); - return 0; -} - static int nfs4_wait_clnt_recover(struct nfs_client *clp) { int res; @@ -208,7 +200,7 @@ static int nfs4_wait_clnt_recover(struct nfs_client *clp) might_sleep(); res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING, - nfs4_wait_bit_killable, TASK_KILLABLE); + nfs_wait_bit_killable, TASK_KILLABLE); return res; } diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 7f079209d70..e2975939126 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -176,17 +176,6 @@ void nfs_release_request(struct nfs_page *req) kref_put(&req->wb_kref, nfs_free_request); } -static int nfs_wait_bit_killable(void *word) -{ - int ret = 0; - - if (fatal_signal_pending(current)) - ret = -ERESTARTSYS; - else - schedule(); - return ret; -} - /** * nfs_wait_on_request - Wait for a request to complete. * @req: request to wait upon. diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 1a999939fed..36fd35e0de8 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -313,19 +313,34 @@ static int nfs_writepages_callback(struct page *page, struct writeback_control * int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) { struct inode *inode = mapping->host; + unsigned long *bitlock = &NFS_I(inode)->flags; struct nfs_pageio_descriptor pgio; int err; + /* Stop dirtying of new pages while we sync */ + err = wait_on_bit_lock(bitlock, NFS_INO_FLUSHING, + nfs_wait_bit_killable, TASK_KILLABLE); + if (err) + goto out_err; + nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); nfs_pageio_init_write(&pgio, inode, wb_priority(wbc)); err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio); nfs_pageio_complete(&pgio); + + clear_bit_unlock(NFS_INO_FLUSHING, bitlock); + smp_mb__after_clear_bit(); + wake_up_bit(bitlock, NFS_INO_FLUSHING); + if (err < 0) - return err; - if (pgio.pg_error < 0) - return pgio.pg_error; + goto out_err; + err = pgio.pg_error; + if (err < 0) + goto out_err; return 0; +out_err: + return err; } /* @@ -1432,18 +1447,13 @@ static int nfs_write_mapping(struct address_space *mapping, int how) { struct writeback_control wbc = { .bdi = mapping->backing_dev_info, - .sync_mode = WB_SYNC_NONE, + .sync_mode = WB_SYNC_ALL, .nr_to_write = LONG_MAX, .range_start = 0, .range_end = LLONG_MAX, .for_writepages = 1, }; - int ret; - ret = __nfs_write_mapping(mapping, &wbc, how); - if (ret < 0) - return ret; - wbc.sync_mode = WB_SYNC_ALL; return __nfs_write_mapping(mapping, &wbc, how); } diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index c9fecd3e8f0..933bc261c0d 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -206,6 +206,7 @@ struct nfs_inode { #define NFS_INO_STALE (1) /* possible stale inode */ #define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */ #define NFS_INO_MOUNTPOINT (3) /* inode is remote mountpoint */ +#define NFS_INO_FLUSHING (4) /* inode is flushing out data */ static inline struct nfs_inode *NFS_I(const struct inode *inode) {