linux/fs/ext4/ialloc.c, branch v3.9

ext4: use atomic64_t for the per-flexbg free_clusters count

2013-03-12T03:39:59Z

A user who was using a 8TB+ file system and with a very large flexbg size (> 65536) could cause the atomic_t used in the struct flex_groups to overflow. This was detected by PaX security patchset: http://forums.grsecurity.net/viewtopic.php?f=3&t=3289&p=12551#p12551 This bug was introduced in commit 9f24e4208f7e, so it's been around since 2.6.30. :-( Fix this by using an atomic64_t for struct orlav_stats's free_clusters. Signed-off-by: "Theodore Ts'o" Reviewed-by: Lukas Czerner Cc: stable@vger.kernel.org

ext4: use KERN_WARNING for warning messages

2013-02-14T20:11:41Z

Some messages printed related to a WARN_ON(1) were printed using KERN_NOTICE. Use KERN_WARNING or ext4_warning() instead so that context related to the WARN_ON() is printed at the same printk warning level (and log files, etc.) Signed-off-by: "Theodore Ts'o"

ext4: start handle at the last possible moment when creating inodes

2013-02-09T21:27:09Z

In ext4_{create,mknod,mkdir,symlink}(), don't start the journal handle until the inode has been succesfully allocated. In order to do this, we need to start the handle in the ext4_new_inode(). So create a new variant of this function, ext4_new_inode_start_handle(), so the handle can be created at the last possible minute, before we need to modify the inode allocation bitmap block. Signed-off-by: "Theodore Ts'o"

ext4: pass context information to jbd2__journal_start()

2013-02-09T02:59:22Z

So we can better understand what bits of ext4 are responsible for long-running jbd2 handles, use jbd2__journal_start() so we can pass context information for logging purposes. The recommended way for finding the longer-running handles is: T=/sys/kernel/debug/tracing EVENT=$T/events/jbd2/jbd2_handle_stats echo "interval > 5" > $EVENT/filter echo 1 > $EVENT/enable ./run-my-fs-benchmark cat $T/trace > /tmp/problem-handles This will list handles that were active for longer than 20ms. Having longer-running handles is bad, because a commit started at the wrong time could stall for those 20+ milliseconds, which could delay an fsync() or an O_SYNC operation. Here is an example line from the trace file describing a handle which lived on for 311 jiffies, or over 1.2 seconds: postmark-2917 [000] .... 196.435786: jbd2_handle_stats: dev 254,32 tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1 dirtied_blocks 0 Signed-off-by: "Theodore Ts'o"

ext4: enable ext4 inline support

2012-12-10T19:06:03Z

Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o"

ext4: fix possible use after free with metadata csum

2012-11-30T02:21:22Z

Commit fa77dcfafeaa introduces block bitmap checksum calculation into ext4_new_inode() in the case that block group was uninitialized. However we brelse() the bitmap buffer before we attempt to checksum it so we have no guarantee that the buffer is still there. Fix this by releasing the buffer after the possible checksum computation. Signed-off-by: Lukas Czerner Signed-off-by: "Theodore Ts'o" Acked-by: Darrick J. Wong Cc: stable@vger.kernel.org

ext4: fix unjournaled inode bitmap modification

2012-10-29T02:24:57Z

commit 119c0d4460b001e44b41dcf73dc6ee794b98bd31 changed ext4_new_inode() such that the inode bitmap was being modified outside a transaction, which could lead to corruption, and was discovered when journal_checksum found a bad checksum in the journal during log replay. Nix ran into this when using the journal_async_commit mount option, which enables journal checksumming. The ensuing journal replay failures due to the bad checksums led to filesystem corruption reported as the now infamous "Apparent serious progressive ext4 data corruption bug" [ Changed by tytso to only call ext4_journal_get_write_access() only when we're fairly certain that we're going to allocate the inode. ] I've tested this by mounting with journal_checksum and running fsstress then dropping power; I've also tested by hacking DM to create snapshots w/o first quiescing, which allows me to test journal replay repeatedly w/o actually power-cycling the box. Without the patch I hit a journal checksum error every time. With this fix it survives many iterations. Reported-by: Nix Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org

ext4: Checksum the block bitmap properly with bigalloc enabled

2012-10-22T04:34:32Z

In mke2fs, we only checksum the whole bitmap block and it is right. While in the kernel, we use EXT4_BLOCKS_PER_GROUP to indicate the size of the checksumed bitmap which is wrong when we enable bigalloc. The right size should be EXT4_CLUSTERS_PER_GROUP and this patch fixes it. Also as every caller of ext4_block_bitmap_csum_set and ext4_block_bitmap_csum_verify pass in EXT4_BLOCKS_PER_GROUP(sb)/8, we'd better removes this parameter and sets it in the function itself. Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o" Reviewed-by: Lukas Czerner Cc: stable@vger.kernel.org

ext4: check free inode count before allocating an inode

2012-09-24T03:16:03Z

Recently, I ecountered some corrupted filesystems in which some groups' free inode counts were 65535, it seemed that free inode count was overflow. This patch teaches ext4 to check free inode count before allocaing an inode. Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o"

ext4: remove useless marking of superblock dirty

2012-07-23T00:29:31Z

Commit a0375156 properly notes that superblock doesn't need to be marked as dirty when only number of free inodes / blocks / number of directories changes since that is recomputed on each mount anyway. However that comment leaves some unnecessary markings as dirty in place. Remove these. Artem: tested using xfstests for both journalled and non-journalled ext4. Signed-off-by: Jan Kara Signed-off-by: Artem Bityutskiy Signed-off-by: "Theodore Ts'o" Tested-by: Artem Bityutskiy