12 files changed, 107 insertions, 68 deletions

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index cfbfa15a46ba..ec6a9392a173 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -97,8 +97,8 @@ prototypes:
         void (*put_super) (struct super_block *);
         void (*write_super) (struct super_block *);
         int (*sync_fs)(struct super_block *sb, int wait);
-        void (*write_super_lockfs) (struct super_block *);
-        void (*unlockfs) (struct super_block *);
+        int (*freeze_fs) (struct super_block *);
+        int (*unfreeze_fs) (struct super_block *);
         int (*statfs) (struct dentry *, struct kstatfs *);
         int (*remount_fs) (struct super_block *, int *, char *);
         void (*clear_inode) (struct inode *);
@@ -119,8 +119,8 @@ delete_inode:		no
 put_super:              yes     yes     no
 write_super:            no      yes     read
 sync_fs:                no      no      read
-write_super_lockfs:     ?
-unlockfs:               ?
+freeze_fs:              ?
+unfreeze_fs:            ?
 statfs:                 no      no      no
 remount_fs:             yes     yes     maybe           (see below)
 clear_inode:            no
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index ef19afa186a9..deeeed0faa8f 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -210,8 +210,8 @@ struct super_operations {
         void (*put_super) (struct super_block *);
         void (*write_super) (struct super_block *);
         int (*sync_fs)(struct super_block *sb, int wait);
-        void (*write_super_lockfs) (struct super_block *);
-        void (*unlockfs) (struct super_block *);
+        int (*freeze_fs) (struct super_block *);
+        int (*unfreeze_fs) (struct super_block *);
         int (*statfs) (struct dentry *, struct kstatfs *);
         int (*remount_fs) (struct super_block *, int *, char *);
         void (*clear_inode) (struct inode *);
@@ -270,11 +270,11 @@ or bottom half).
         a superblock. The second parameter indicates whether the method
         should wait until the write out has been completed. Optional.
 
-  write_super_lockfs: called when VFS is locking a filesystem and
+  freeze_fs: called when VFS is locking a filesystem and
         forcing it into a consistent state.  This method is currently
         used by the Logical Volume Manager (LVM).
 
-  unlockfs: called when VFS is unlocking a filesystem and making it writable
+  unfreeze_fs: called when VFS is unlocking a filesystem and making it writable
         again.
 
   statfs: called when the VFS needs to get filesystem statistics. This
diff --git a/fs/buffer.c b/fs/buffer.c
index c26da785938a..87f9e537b8c3 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -221,8 +221,8 @@ struct super_block *freeze_bdev(struct block_device *bdev)
 
                 sync_blockdev(sb->s_bdev);
 
-                if (sb->s_op->write_super_lockfs)
-                        sb->s_op->write_super_lockfs(sb);
+                if (sb->s_op->freeze_fs)
+                        sb->s_op->freeze_fs(sb);
         }
 
         sync_blockdev(bdev);
@@ -242,8 +242,8 @@ void thaw_bdev(struct block_device *bdev, struct super_block *sb)
         if (sb) {
                 BUG_ON(sb->s_bdev != bdev);
 
-                if (sb->s_op->unlockfs)
-                        sb->s_op->unlockfs(sb);
+                if (sb->s_op->unfreeze_fs)
+                        sb->s_op->unfreeze_fs(sb);
                 sb->s_frozen = SB_UNFROZEN;
                 smp_wmb();
                 wake_up(&sb->s_wait_unfrozen);
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index 5d047a030a73..b70d90e08a3c 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -48,8 +48,8 @@ static int ext3_load_journal(struct super_block *, struct ext3_super_block *,
                              unsigned long journal_devnum);
 static int ext3_create_journal(struct super_block *, struct ext3_super_block *,
                                unsigned int);
-static void ext3_commit_super (struct super_block * sb,
-                               struct ext3_super_block * es,
+static int ext3_commit_super(struct super_block *sb,
+                               struct ext3_super_block *es,
                                int sync);
 static void ext3_mark_recovery_complete(struct super_block * sb,
                                         struct ext3_super_block * es);
@@ -60,9 +60,9 @@ static const char *ext3_decode_error(struct super_block * sb, int errno,
                                      char nbuf[16]);
 static int ext3_remount (struct super_block * sb, int * flags, char * data);
 static int ext3_statfs (struct dentry * dentry, struct kstatfs * buf);
-static void ext3_unlockfs(struct super_block *sb);
+static int ext3_unfreeze(struct super_block *sb);
 static void ext3_write_super (struct super_block * sb);
-static void ext3_write_super_lockfs(struct super_block *sb);
+static int ext3_freeze(struct super_block *sb);
 
 /*
  * Wrappers for journal_start/end.
@@ -759,8 +759,8 @@ static const struct super_operations ext3_sops = {
         .put_super      = ext3_put_super,
         .write_super    = ext3_write_super,
         .sync_fs        = ext3_sync_fs,
-        .write_super_lockfs = ext3_write_super_lockfs,
-        .unlockfs       = ext3_unlockfs,
+        .freeze_fs      = ext3_freeze,
+        .unfreeze_fs    = ext3_unfreeze,
         .statfs         = ext3_statfs,
         .remount_fs     = ext3_remount,
         .clear_inode    = ext3_clear_inode,
@@ -2311,21 +2311,23 @@ static int ext3_create_journal(struct super_block * sb,
         return 0;
 }
 
-static void ext3_commit_super (struct super_block * sb,
-                               struct ext3_super_block * es,
+static int ext3_commit_super(struct super_block *sb,
+                               struct ext3_super_block *es,
                                int sync)
 {
         struct buffer_head *sbh = EXT3_SB(sb)->s_sbh;
+        int error = 0;
 
         if (!sbh)
-                return;
+                return error;
         es->s_wtime = cpu_to_le32(get_seconds());
         es->s_free_blocks_count = cpu_to_le32(ext3_count_free_blocks(sb));
         es->s_free_inodes_count = cpu_to_le32(ext3_count_free_inodes(sb));
         BUFFER_TRACE(sbh, "marking dirty");
         mark_buffer_dirty(sbh);
         if (sync)
-                sync_dirty_buffer(sbh);
+                error = sync_dirty_buffer(sbh);
+        return error;
 }
 
 
@@ -2439,12 +2441,14 @@ static int ext3_sync_fs(struct super_block *sb, int wait)
  * LVM calls this function before a (read-only) snapshot is created.  This
  * gives us a chance to flush the journal completely and mark the fs clean.
  */
-static void ext3_write_super_lockfs(struct super_block *sb)
+static int ext3_freeze(struct super_block *sb)
 {
+        int error = 0;
+        journal_t *journal;
         sb->s_dirt = 0;
 
         if (!(sb->s_flags & MS_RDONLY)) {
-                journal_t *journal = EXT3_SB(sb)->s_journal;
+                journal = EXT3_SB(sb)->s_journal;
 
                 /* Now we set up the journal barrier. */
                 journal_lock_updates(journal);
@@ -2453,20 +2457,28 @@ static void ext3_write_super_lockfs(struct super_block *sb)
                  * We don't want to clear needs_recovery flag when we failed
                  * to flush the journal.
                  */
-                if (journal_flush(journal) < 0)
-                        return;
+                error = journal_flush(journal);
+                if (error < 0)
+                        goto out;
 
                 /* Journal blocked and flushed, clear needs_recovery flag. */
                 EXT3_CLEAR_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_RECOVER);
-                ext3_commit_super(sb, EXT3_SB(sb)->s_es, 1);
+                error = ext3_commit_super(sb, EXT3_SB(sb)->s_es, 1);
+                if (error)
+                        goto out;
         }
+        return 0;
+
+out:
+        journal_unlock_updates(journal);
+        return error;
 }
 
 /*
  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
  * flag here, even though the filesystem is not technically dirty yet.
  */
-static void ext3_unlockfs(struct super_block *sb)
+static int ext3_unfreeze(struct super_block *sb)
 {
         if (!(sb->s_flags & MS_RDONLY)) {
                 lock_super(sb);
@@ -2476,6 +2488,7 @@ static void ext3_unlockfs(struct super_block *sb)
                 unlock_super(sb);
                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
         }
+        return 0;
 }
 
 static int ext3_remount (struct super_block * sb, int * flags, char * data)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8f7e0be8ab1b..e5f06a5f045e 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -51,7 +51,7 @@ struct proc_dir_entry *ext4_proc_root;
 
 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
                              unsigned long journal_devnum);
-static void ext4_commit_super(struct super_block *sb,
+static int ext4_commit_super(struct super_block *sb,
                               struct ext4_super_block *es, int sync);
 static void ext4_mark_recovery_complete(struct super_block *sb,
                                         struct ext4_super_block *es);
@@ -62,9 +62,9 @@ static const char *ext4_decode_error(struct super_block *sb, int errno,
                                      char nbuf[16]);
 static int ext4_remount(struct super_block *sb, int *flags, char *data);
 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
-static void ext4_unlockfs(struct super_block *sb);
+static int ext4_unfreeze(struct super_block *sb);
 static void ext4_write_super(struct super_block *sb);
-static void ext4_write_super_lockfs(struct super_block *sb);
+static int ext4_freeze(struct super_block *sb);
 
 
 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
@@ -978,8 +978,8 @@ static const struct super_operations ext4_sops = {
         .put_super      = ext4_put_super,
         .write_super    = ext4_write_super,
         .sync_fs        = ext4_sync_fs,
-        .write_super_lockfs = ext4_write_super_lockfs,
-        .unlockfs       = ext4_unlockfs,
+        .freeze_fs      = ext4_freeze,
+        .unfreeze_fs    = ext4_unfreeze,
         .statfs         = ext4_statfs,
         .remount_fs     = ext4_remount,
         .clear_inode    = ext4_clear_inode,
@@ -2888,13 +2888,14 @@ static int ext4_load_journal(struct super_block *sb,
         return 0;
 }
 
-static void ext4_commit_super(struct super_block *sb,
+static int ext4_commit_super(struct super_block *sb,
                               struct ext4_super_block *es, int sync)
 {
         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
+        int error = 0;
 
         if (!sbh)
-                return;
+                return error;
         if (buffer_write_io_error(sbh)) {
                 /*
                  * Oh, dear.  A previous attempt to write the
@@ -2918,14 +2919,19 @@ static void ext4_commit_super(struct super_block *sb,
         BUFFER_TRACE(sbh, "marking dirty");
         mark_buffer_dirty(sbh);
         if (sync) {
-                sync_dirty_buffer(sbh);
-                if (buffer_write_io_error(sbh)) {
+                error = sync_dirty_buffer(sbh);
+                if (error)
+                        return error;
+
+                error = buffer_write_io_error(sbh);
+                if (error) {
                         printk(KERN_ERR "EXT4-fs: I/O error while writing "
                                "superblock for %s.\n", sb->s_id);
                         clear_buffer_write_io_error(sbh);
                         set_buffer_uptodate(sbh);
                 }
         }
+        return error;
 }
 
 
@@ -3058,12 +3064,14 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
  * LVM calls this function before a (read-only) snapshot is created.  This
  * gives us a chance to flush the journal completely and mark the fs clean.
  */
-static void ext4_write_super_lockfs(struct super_block *sb)
+static int ext4_freeze(struct super_block *sb)
 {
+        int error = 0;
+        journal_t *journal;
         sb->s_dirt = 0;
 
         if (!(sb->s_flags & MS_RDONLY)) {
-                journal_t *journal = EXT4_SB(sb)->s_journal;
+                journal = EXT4_SB(sb)->s_journal;
 
                 if (journal) {
                         /* Now we set up the journal barrier. */
@@ -3073,21 +3081,29 @@ static void ext4_write_super_lockfs(struct super_block *sb)
                          * We don't want to clear needs_recovery flag when we
                          * failed to flush the journal.
                          */
-                        if (jbd2_journal_flush(journal) < 0)
-                                return;
+                        error = jbd2_journal_flush(journal);
+                        if (error < 0)
+                                goto out;
                 }
 
                 /* Journal blocked and flushed, clear needs_recovery flag. */
                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+                error = ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+                if (error)
+                        goto out;
         }
+        return 0;
+out:
+        jbd2_journal_unlock_updates(journal);
+        return error;
 }
 
 /*
  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
  * flag here, even though the filesystem is not technically dirty yet.
  */
-static void ext4_unlockfs(struct super_block *sb)
+static int ext4_unfreeze(struct super_block *sb)
 {
         if (EXT4_SB(sb)->s_journal && !(sb->s_flags & MS_RDONLY)) {
                 lock_super(sb);
@@ -3097,6 +3113,7 @@ static void ext4_unlockfs(struct super_block *sb)
                 unlock_super(sb);
                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
         }
+        return 0;
 }
 
 static int ext4_remount(struct super_block *sb, int *flags, char *data)
diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 777783deddcb..320323d03479 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -211,18 +211,18 @@ static int gfs2_sync_fs(struct super_block *sb, int wait)
 }
 
 /**
- * gfs2_write_super_lockfs - prevent further writes to the filesystem
+ * gfs2_freeze - prevent further writes to the filesystem
  * @sb: the VFS structure for the filesystem
  *
  */
 
-static void gfs2_write_super_lockfs(struct super_block *sb)
+static int gfs2_freeze(struct super_block *sb)
 {
         struct gfs2_sbd *sdp = sb->s_fs_info;
         int error;
 
         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
-                return;
+                return -EINVAL;
 
         for (;;) {
                 error = gfs2_freeze_fs(sdp);
@@ -242,17 +242,19 @@ static void gfs2_write_super_lockfs(struct super_block *sb)
                 fs_err(sdp, "retrying...\n");
                 msleep(1000);
         }
+        return 0;
 }
 
 /**
- * gfs2_unlockfs - reallow writes to the filesystem
+ * gfs2_unfreeze - reallow writes to the filesystem
  * @sb: the VFS structure for the filesystem
  *
  */
 
-static void gfs2_unlockfs(struct super_block *sb)
+static int gfs2_unfreeze(struct super_block *sb)
 {
         gfs2_unfreeze_fs(sb->s_fs_info);
+        return 0;
 }
 
 /**
@@ -688,8 +690,8 @@ const struct super_operations gfs2_super_ops = {
         .put_super              = gfs2_put_super,
         .write_super            = gfs2_write_super,
         .sync_fs                = gfs2_sync_fs,
-        .write_super_lockfs     = gfs2_write_super_lockfs,
-        .unlockfs               = gfs2_unlockfs,
+        .freeze_fs              = gfs2_freeze,
+        .unfreeze_fs            = gfs2_unfreeze,
         .statfs                 = gfs2_statfs,
         .remount_fs             = gfs2_remount_fs,
         .clear_inode            = gfs2_clear_inode,
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 0dae345e481b..b37d1f78b854 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -543,7 +543,7 @@ out_kfree:
         return ret;
 }
 
-static void jfs_write_super_lockfs(struct super_block *sb)
+static int jfs_freeze(struct super_block *sb)
 {
         struct jfs_sb_info *sbi = JFS_SBI(sb);
         struct jfs_log *log = sbi->log;
@@ -553,9 +553,10 @@ static void jfs_write_super_lockfs(struct super_block *sb)
                 lmLogShutdown(log);
                 updateSuper(sb, FM_CLEAN);
         }
+        return 0;
 }
 
-static void jfs_unlockfs(struct super_block *sb)
+static int jfs_unfreeze(struct super_block *sb)
 {
         struct jfs_sb_info *sbi = JFS_SBI(sb);
         struct jfs_log *log = sbi->log;
@@ -568,6 +569,7 @@ static void jfs_unlockfs(struct super_block *sb)
                 else
                         txResume(sb);
         }
+        return 0;
 }
 
 static int jfs_get_sb(struct file_system_type *fs_type,
@@ -735,8 +737,8 @@ static const struct super_operations jfs_super_operations = {
         .delete_inode   = jfs_delete_inode,
         .put_super      = jfs_put_super,
         .sync_fs        = jfs_sync_fs,
-        .write_super_lockfs = jfs_write_super_lockfs,
-        .unlockfs       = jfs_unlockfs,
+        .freeze_fs      = jfs_freeze,
+        .unfreeze_fs    = jfs_unfreeze,
         .statfs         = jfs_statfs,
         .remount_fs     = jfs_remount,
         .show_options   = jfs_show_options,
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index c55651f1407c..f3c820b75829 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -83,7 +83,7 @@ static void reiserfs_write_super(struct super_block *s)
         reiserfs_sync_fs(s, 1);
 }
 
-static void reiserfs_write_super_lockfs(struct super_block *s)
+static int reiserfs_freeze(struct super_block *s)
 {
         struct reiserfs_transaction_handle th;
         reiserfs_write_lock(s);
@@ -101,11 +101,13 @@ static void reiserfs_write_super_lockfs(struct super_block *s)
         }
         s->s_dirt = 0;
         reiserfs_write_unlock(s);
+        return 0;
 }
 
-static void reiserfs_unlockfs(struct super_block *s)
+static int reiserfs_unfreeze(struct super_block *s)
 {
         reiserfs_allow_writes(s);
+        return 0;
 }
 
 extern const struct in_core_key MAX_IN_CORE_KEY;
@@ -613,8 +615,8 @@ static const struct super_operations reiserfs_sops = {
         .put_super = reiserfs_put_super,
         .write_super = reiserfs_write_super,
         .sync_fs = reiserfs_sync_fs,
-        .write_super_lockfs = reiserfs_write_super_lockfs,
-        .unlockfs = reiserfs_unlockfs,
+        .freeze_fs = reiserfs_freeze,
+        .unfreeze_fs = reiserfs_unfreeze,
         .statfs = reiserfs_statfs,
         .remount_fs = reiserfs_remount,
         .show_options = generic_show_options,
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index be846d606ae8..95a971080368 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -1269,14 +1269,14 @@ xfs_fs_remount(
  * need to take care of the metadata. Once that's done write a dummy
  * record to dirty the log in case of a crash while frozen.
  */
-STATIC void
-xfs_fs_lockfs(
+STATIC int
+xfs_fs_freeze(
         struct super_block      *sb)
 {
         struct xfs_mount        *mp = XFS_M(sb);
 
         xfs_quiesce_attr(mp);
-        xfs_fs_log_dummy(mp);
+        return -xfs_fs_log_dummy(mp);
 }
 
 STATIC int
@@ -1557,7 +1557,7 @@ static struct super_operations xfs_super_operations = {
         .put_super              = xfs_fs_put_super,
         .write_super            = xfs_fs_write_super,
         .sync_fs                = xfs_fs_sync_super,
-        .write_super_lockfs     = xfs_fs_lockfs,
+        .freeze_fs              = xfs_fs_freeze,
         .statfs                 = xfs_fs_statfs,
         .remount_fs             = xfs_fs_remount,
         .show_options           = xfs_fs_show_options,
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 852b6d32e8d0..680d0e0ec932 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -595,17 +595,19 @@ out:
         return 0;
 }
 
-void
+int
 xfs_fs_log_dummy(
         xfs_mount_t     *mp)
 {
         xfs_trans_t     *tp;
         xfs_inode_t     *ip;
+        int             error;
 
         tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
-        if (xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0)) {
+        error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0);
+        if (error) {
                 xfs_trans_cancel(tp, 0);
-                return;
+                return error;
         }
 
         ip = mp->m_rootip;
@@ -615,9 +617,10 @@ xfs_fs_log_dummy(
         xfs_trans_ihold(tp, ip);
         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
         xfs_trans_set_sync(tp);
-        xfs_trans_commit(tp, 0);
+        error = xfs_trans_commit(tp, 0);
 
         xfs_iunlock(ip, XFS_ILOCK_EXCL);
+        return error;
 }
 
 int
diff --git a/fs/xfs/xfs_fsops.h b/fs/xfs/xfs_fsops.h
index 300d0c9d61ad..88435e0a77c9 100644
--- a/fs/xfs/xfs_fsops.h
+++ b/fs/xfs/xfs_fsops.h
@@ -25,6 +25,6 @@ extern int xfs_fs_counts(xfs_mount_t *mp, xfs_fsop_counts_t *cnt);
 extern int xfs_reserve_blocks(xfs_mount_t *mp, __uint64_t *inval,
                                 xfs_fsop_resblks_t *outval);
 extern int xfs_fs_goingdown(xfs_mount_t *mp, __uint32_t inflags);
-extern void xfs_fs_log_dummy(xfs_mount_t *mp);
+extern int xfs_fs_log_dummy(xfs_mount_t *mp);
 
 #endif  /* __XFS_FSOPS_H__ */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 0b87b29f4797..3e59182de9df 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1377,8 +1377,8 @@ struct super_operations {
         void (*put_super) (struct super_block *);
         void (*write_super) (struct super_block *);
         int (*sync_fs)(struct super_block *sb, int wait);
-        void (*write_super_lockfs) (struct super_block *);
-        void (*unlockfs) (struct super_block *);
+        int (*freeze_fs) (struct super_block *);
+        int (*unfreeze_fs) (struct super_block *);
         int (*statfs) (struct dentry *, struct kstatfs *);
         int (*remount_fs) (struct super_block *, int *, char *);
         void (*clear_inode) (struct inode *);