btrfs: modify local copy of btrfs_inode flags

Instead of updating the binode::flags directly, update a local copy, and
then at the point of no error, store copy it to the binode::flags.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 4f235f4..add724e 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -189,9 +189,9 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
        struct btrfs_trans_handle *trans;
        unsigned int fsflags, old_fsflags;
        int ret;
-       u64 old_flags;
        umode_t mode;
        const char *comp = NULL;
+       u32 binode_flags = binode->flags;
 
        if (!inode_owner_or_capable(inode))
                return -EPERM;
@@ -212,7 +212,6 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 
        inode_lock(inode);
 
-       old_flags = binode->flags;
        mode = inode->i_mode;
 
        fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
@@ -225,29 +224,29 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
        }
 
        if (fsflags & FS_SYNC_FL)
-               binode->flags |= BTRFS_INODE_SYNC;
+               binode_flags |= BTRFS_INODE_SYNC;
        else
-               binode->flags &= ~BTRFS_INODE_SYNC;
+               binode_flags &= ~BTRFS_INODE_SYNC;
        if (fsflags & FS_IMMUTABLE_FL)
-               binode->flags |= BTRFS_INODE_IMMUTABLE;
+               binode_flags |= BTRFS_INODE_IMMUTABLE;
        else
-               binode->flags &= ~BTRFS_INODE_IMMUTABLE;
+               binode_flags &= ~BTRFS_INODE_IMMUTABLE;
        if (fsflags & FS_APPEND_FL)
-               binode->flags |= BTRFS_INODE_APPEND;
+               binode_flags |= BTRFS_INODE_APPEND;
        else
-               binode->flags &= ~BTRFS_INODE_APPEND;
+               binode_flags &= ~BTRFS_INODE_APPEND;
        if (fsflags & FS_NODUMP_FL)
-               binode->flags |= BTRFS_INODE_NODUMP;
+               binode_flags |= BTRFS_INODE_NODUMP;
        else
-               binode->flags &= ~BTRFS_INODE_NODUMP;
+               binode_flags &= ~BTRFS_INODE_NODUMP;
        if (fsflags & FS_NOATIME_FL)
-               binode->flags |= BTRFS_INODE_NOATIME;
+               binode_flags |= BTRFS_INODE_NOATIME;
        else
-               binode->flags &= ~BTRFS_INODE_NOATIME;
+               binode_flags &= ~BTRFS_INODE_NOATIME;
        if (fsflags & FS_DIRSYNC_FL)
-               binode->flags |= BTRFS_INODE_DIRSYNC;
+               binode_flags |= BTRFS_INODE_DIRSYNC;
        else
-               binode->flags &= ~BTRFS_INODE_DIRSYNC;
+               binode_flags &= ~BTRFS_INODE_DIRSYNC;
        if (fsflags & FS_NOCOW_FL) {
                if (S_ISREG(mode)) {
                        /*
@@ -256,10 +255,10 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
                         * status of the file and will not set it.
                         */
                        if (inode->i_size == 0)
-                               binode->flags |= BTRFS_INODE_NODATACOW
-                                             | BTRFS_INODE_NODATASUM;
+                               binode_flags |= BTRFS_INODE_NODATACOW |
+                                               BTRFS_INODE_NODATASUM;
                } else {
-                       binode->flags |= BTRFS_INODE_NODATACOW;
+                       binode_flags |= BTRFS_INODE_NODATACOW;
                }
        } else {
                /*
@@ -267,10 +266,10 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
                 */
                if (S_ISREG(mode)) {
                        if (inode->i_size == 0)
-                               binode->flags &= ~(BTRFS_INODE_NODATACOW
-                                            | BTRFS_INODE_NODATASUM);
+                               binode_flags &= ~(BTRFS_INODE_NODATACOW |
+                                                 BTRFS_INODE_NODATASUM);
                } else {
-                       binode->flags &= ~BTRFS_INODE_NODATACOW;
+                       binode_flags &= ~BTRFS_INODE_NODATACOW;
                }
        }
 
@@ -280,8 +279,8 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
         * things smaller.
         */
        if (fsflags & FS_NOCOMP_FL) {
-               binode->flags &= ~BTRFS_INODE_COMPRESS;
-               binode->flags |= BTRFS_INODE_NOCOMPRESS;
+               binode_flags &= ~BTRFS_INODE_COMPRESS;
+               binode_flags |= BTRFS_INODE_NOCOMPRESS;
        } else if (fsflags & FS_COMPR_FL) {
 
                if (IS_SWAPFILE(inode)) {
@@ -289,14 +288,14 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
                        goto out_unlock;
                }
 
-               binode->flags |= BTRFS_INODE_COMPRESS;
-               binode->flags &= ~BTRFS_INODE_NOCOMPRESS;
+               binode_flags |= BTRFS_INODE_COMPRESS;
+               binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
 
                comp = btrfs_compress_type2str(fs_info->compress_type);
                if (!comp || comp[0] == 0)
                        comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
        } else {
-               binode->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
+               binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
        }
 
        /*
@@ -306,7 +305,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
        trans = btrfs_start_transaction(root, 3);
        if (IS_ERR(trans)) {
                ret = PTR_ERR(trans);
-               goto out_drop;
+               goto out_unlock;
        }
 
        if (comp) {
@@ -327,6 +326,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
                }
        }
 
+       binode->flags = binode_flags;
        btrfs_sync_inode_flags_to_i_flags(inode);
        inode_inc_iversion(inode);
        inode->i_ctime = current_time(inode);
@@ -334,11 +334,6 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 
  out_end_trans:
        btrfs_end_transaction(trans);
- out_drop:
-       if (ret) {
-               binode->flags = old_flags;
-       }
-
  out_unlock:
        inode_unlock(inode);
        mnt_drop_write_file(file);