Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 84a8dce2 authored by Dmitry Monakhov's avatar Dmitry Monakhov Committed by Theodore Ts'o
Browse files

ext4: Fix remaining racy updates of EXT4_I(inode)->i_flags 



A few functions were still modifying i_flags in a racy manner.

Signed-off-by: default avatarDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 1f5a81e4

fs/ext4/inode.c

+23 −17
Original line number Diff line number Diff line
@@ -4942,20 +4942,26 @@ void ext4_set_inode_flags(struct inode *inode) 
/* Propagate flags from i_flags to EXT4_I(inode)->i_flags */

void ext4_get_inode_flags(struct ext4_inode_info *ei)

{

	unsigned int flags = ei->vfs_inode.i_flags;



	ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL|

			EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL);

	if (flags & S_SYNC)

		ei->i_flags |= EXT4_SYNC_FL;

	if (flags & S_APPEND)

		ei->i_flags |= EXT4_APPEND_FL;

	if (flags & S_IMMUTABLE)

		ei->i_flags |= EXT4_IMMUTABLE_FL;

	if (flags & S_NOATIME)

		ei->i_flags |= EXT4_NOATIME_FL;

	if (flags & S_DIRSYNC)

		ei->i_flags |= EXT4_DIRSYNC_FL;

	unsigned int vfs_fl;

	unsigned long old_fl, new_fl;



	do {

		vfs_fl = ei->vfs_inode.i_flags;

		old_fl = ei->i_flags;

		new_fl = old_fl & ~(EXT4_SYNC_FL|EXT4_APPEND_FL|

				EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|

				EXT4_DIRSYNC_FL);

		if (vfs_fl & S_SYNC)

			new_fl |= EXT4_SYNC_FL;

		if (vfs_fl & S_APPEND)

			new_fl |= EXT4_APPEND_FL;

		if (vfs_fl & S_IMMUTABLE)

			new_fl |= EXT4_IMMUTABLE_FL;

		if (vfs_fl & S_NOATIME)

			new_fl |= EXT4_NOATIME_FL;

		if (vfs_fl & S_DIRSYNC)

			new_fl |= EXT4_DIRSYNC_FL;

	} while (cmpxchg(&ei->i_flags, old_fl, new_fl) != old_fl);

}



static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
@@ -5191,7 +5197,7 @@ static int ext4_inode_blocks_set(handle_t *handle, 
		 */

		raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);

		raw_inode->i_blocks_high = 0;

		ei->i_flags &= ~EXT4_HUGE_FILE_FL;

		ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);

		return 0;

	}

	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE))
@@ -5204,9 +5210,9 @@ static int ext4_inode_blocks_set(handle_t *handle, 
		 */

		raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);

		raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);

		ei->i_flags &= ~EXT4_HUGE_FILE_FL;

		ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);

	} else {

		ei->i_flags |= EXT4_HUGE_FILE_FL;

		ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE);

		/* i_block is stored in file system block size */

		i_blocks = i_blocks >> (inode->i_blkbits - 9);

		raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);