kernel/git/stable/linux.git/fs/ext4/inode.c, branch linux-3.5.y

ext4: fix fdatasync() for files with only i_size changes

2012-10-12T20:47:10+00:00

commit b71fc079b5d8f42b2a52743c8d2f1d35d655b1c5 upstream. Code tracking when transaction needs to be committed on fdatasync(2) forgets to handle a situation when only inode's i_size is changed. Thus in such situations fdatasync(2) doesn't force transaction with new i_size to disk and that can result in wrong i_size after a crash. Fix the issue by updating inode's i_datasync_tid whenever its size is updated. Reported-by: Kristian Nielsen Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

ext4: fix potential deadlock in ext4_nonda_switch()

2012-10-12T20:47:08+00:00

commit 00d4e7362ed01987183e9528295de3213031309c upstream. In ext4_nonda_switch(), if the file system is getting full we used to call writeback_inodes_sb_if_idle(). The problem is that we can be holding i_mutex already, and this causes a potential deadlock when writeback_inodes_sb_if_idle() when it tries to take s_umount. (See lockdep output below). As it turns out we don't need need to hold s_umount; the fact that we are in the middle of the write(2) system call will keep the superblock pinned. Unfortunately writeback_inodes_sb() checks to make sure s_umount is taken, and the VFS uses a different mechanism for making sure the file system doesn't get unmounted out from under us. The simplest way of dealing with this is to just simply grab s_umount using a trylock, and skip kicking the writeback flusher thread in the very unlikely case that we can't take a read lock on s_umount without blocking. Also, we now check the cirteria for kicking the writeback thread before we decide to whether to fall back to non-delayed writeback, so if there are any outstanding delayed allocation writes, we try to get them resolved as soon as possible. [ INFO: possible circular locking dependency detected ] 3.6.0-rc1-00042-gce894ca #367 Not tainted ------------------------------------------------------- dd/8298 is trying to acquire lock: (&type->s_umount_key#18){++++..}, at: [] writeback_inodes_sb_if_idle+0x28/0x46 but task is already holding lock: (&sb->s_type->i_mutex_key#8){+.+...}, at: [] generic_file_aio_write+0x5f/0xd3 which lock already depends on the new lock. 2 locks held by dd/8298: #0: (sb_writers#2){.+.+.+}, at: [] generic_file_aio_write+0x56/0xd3 #1: (&sb->s_type->i_mutex_key#8){+.+...}, at: [] generic_file_aio_write+0x5f/0xd3 stack backtrace: Pid: 8298, comm: dd Not tainted 3.6.0-rc1-00042-gce894ca #367 Call Trace: [] ? console_unlock+0x345/0x372 [] print_circular_bug+0x190/0x19d [] __lock_acquire+0x86d/0xb6c [] ? mark_held_locks+0x5c/0x7b [] lock_acquire+0x66/0xb9 [] ? writeback_inodes_sb_if_idle+0x28/0x46 [] down_read+0x28/0x58 [] ? writeback_inodes_sb_if_idle+0x28/0x46 [] writeback_inodes_sb_if_idle+0x28/0x46 [] ext4_nonda_switch+0xe1/0xf4 [] ext4_da_write_begin+0x27/0x193 [] generic_file_buffered_write+0xc8/0x1bb [] __generic_file_aio_write+0x1dd/0x205 [] generic_file_aio_write+0x78/0xd3 [] ext4_file_write+0x480/0x4a6 [] ? __lock_acquire+0x41e/0xb6c [] ? sched_clock_cpu+0x11a/0x13e [] ? trace_hardirqs_off+0xb/0xd [] ? local_clock+0x37/0x4e [] do_sync_write+0x67/0x9d [] ? wait_on_retry_sync_kiocb+0x44/0x44 [] vfs_write+0x7b/0xe6 [] sys_write+0x3b/0x64 [] syscall_call+0x7/0xb Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman

ext4: undo ext4_calc_metadata_amount if we fail to claim space

2012-08-09T15:23:12+00:00

commit 03179fe92318e7934c180d96f12eff2cb36ef7b6 upstream. The function ext4_calc_metadata_amount() has side effects, although it's not obvious from its function name. So if we fail to claim space, regardless of whether we retry to claim the space again, or return an error, we need to undo these side effects. Otherwise we can end up incorrectly calculating the number of metadata blocks needed for the operation, which was responsible for an xfstests failure for test #271 when using an ext2 file system with delalloc enabled. Reported-by: Brian Foster Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman

ext4: don't let i_reserved_meta_blocks go negative

2012-08-09T15:23:12+00:00

commit 97795d2a5b8d3c8dc4365d4bd3404191840453ba upstream. If we hit a condition where we have allocated metadata blocks that were not appropriately reserved, we risk underflow of ei->i_reserved_meta_blocks. In turn, this can throw sbi->s_dirtyclusters_counter significantly out of whack and undermine the nondelalloc fallback logic in ext4_nonda_switch(). Warn if this occurs and set i_allocated_meta_blocks to avoid this problem. This condition is reproduced by xfstests 270 against ext2 with delalloc enabled: Mar 28 08:58:02 localhost kernel: [ 171.526344] EXT4-fs (loop1): delayed block allocation failed for inode 14 at logical offset 64486 with max blocks 64 with error -28 Mar 28 08:58:02 localhost kernel: [ 171.526346] EXT4-fs (loop1): This should not happen!! Data will be lost 270 ultimately fails with an inconsistent filesystem and requires an fsck to repair. The cause of the error is an underflow in ext4_da_update_reserve_space() due to an unreserved meta block allocation. Signed-off-by: Brian Foster Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2012-06-01T17:12:15+00:00

Pull Ext4 updates from Theodore Ts'o: "The major new feature added in this update is Darrick J Wong's metadata checksum feature, which adds crc32 checksums to ext4's metadata fields. There is also the usual set of cleanups and bug fixes." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits) ext4: hole-punch use truncate_pagecache_range jbd2: use kmem_cache_zalloc wrapper instead of flag ext4: remove mb_groups before tearing down the buddy_cache ext4: add ext4_mb_unload_buddy in the error path ext4: don't trash state flags in EXT4_IOC_SETFLAGS ext4: let getattr report the right blocks in delalloc+bigalloc ext4: add missing save_error_info() to ext4_error() ext4: add debugging trigger for ext4_error() ext4: protect group inode free counting with group lock ext4: use consistent ssize_t type in ext4_file_write() ext4: fix format flag in ext4_ext_binsearch_idx() ext4: cleanup in ext4_discard_allocated_blocks() ext4: return ENOMEM when mounts fail due to lack of memory ext4: remove redundundant "(char *) bh->b_data" casts ext4: disallow hard-linked directory in ext4_lookup ext4: fix potential integer overflow in alloc_flex_gd() ext4: remove needs_recovery in ext4_mb_init() ext4: force ro mount if ext4_setup_super() fails ext4: fix potential NULL dereference in ext4_free_inodes_counts() ext4/jbd2: add metadata checksumming to the list of supported features ...

ext4: let getattr report the right blocks in delalloc+bigalloc

2012-06-01T02:54:16+00:00

In delayed allocation, i_reserved_data_blocks now indicates clusters, not blocks. So report it in the right number. This can be easily exposed by the following command: echo foo > blah; du -hc blah; sync; du -hc blah Reported-by: Eric Sandeen Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o"

userns: Convert ext4 to user kuid/kgid where appropriate

2012-05-15T21:59:27+00:00

Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman

ext4: make block group checksums use metadata_csum algorithm

2012-04-29T22:45:10+00:00

metadata_csum supersedes uninit_bg. Convert the ROCOMPAT uninit_bg flag check to a helper function that covers both, and make the checksum calculation algorithm use either crc16 or the metadata_csum chosen algorithm depending on which flag is set. Print a warning if we try to mount a filesystem with both feature flags set. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o"

ext4: calculate and verify inode checksums

2012-04-29T22:31:10+00:00

This patch introduces to ext4 the ability to calculate and verify inode checksums. This requires the use of a new ro compatibility flag and some accompanying e2fsprogs patches to provide the relevant features in tune2fs and e2fsck. The inode generation changes have been integrated into this patch. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o"

ext4: calculate and verify superblock checksum

2012-04-29T22:29:10+00:00

Calculate and verify the superblock checksum. Since the UUID and block group number are embedded in each copy of the superblock, we need only checksum the entire block. Refactor some of the code to eliminate open-coding of the checksum update call. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o"