talos-op-linux/fs/ext4, branch v3.1-rc3

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2011-08-21T13:59:41+00:00

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: flush any pending end_io requests before DIO reads w/dioread_nolock ext4: fix nomblk_io_submit option so it correctly converts uninit blocks ext4: Resolve the hang of direct i/o read in handling EXT4_IO_END_UNWRITTEN. ext4: call ext4_ioend_wait and ext4_flush_completed_IO in ext4_evict_inode ext4: Fix ext4_should_writeback_data() for no-journal mode

ext4: flush any pending end_io requests before DIO reads w/dioread_nolock

2011-08-19T23:13:32+00:00

There is a race between ext4 buffer write and direct_IO read with dioread_nolock mount option enabled. The problem is that we clear PageWriteback flag during end_io time but will do uninitialized-to-initialized extent conversion later with dioread_nolock. If an O_direct read request comes in during this period, ext4 will return zero instead of the recently written data. This patch checks whether there are any pending uninitialized-to-initialized extent conversion requests before doing O_direct read to close the race. Note that this is just a bandaid fix. The fundamental issue is that we clear PageWriteback flag before we really complete an IO, which is problem-prone. To fix the fundamental issue, we may need to implement an extent tree cache that we can use to look up pending to-be-converted extents. Signed-off-by: Jiaying Zhang Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org

ext4: fix nomblk_io_submit option so it correctly converts uninit blocks

2011-08-13T16:58:21+00:00

Bug discovered by Jan Kara: Finally, commit 1449032be17abb69116dbc393f67ceb8bd034f92 returned back the old IO submission code but apparently it forgot to return the old handling of uninitialized buffers so we unconditionnaly call block_write_full_page() without specifying end_io function. So AFAICS we never convert unwritten extents to written in some cases. For example when I mount the fs as: mount -t ext4 -o nomblk_io_submit,dioread_nolock /dev/ubdb /mnt and do int fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0600); char buf[1024]; memset(buf, 'a', sizeof(buf)); fallocate(fd, 0, 0, 16384); write(fd, buf, sizeof(buf)); I get a file full of zeros (after remounting the filesystem so that pagecache is dropped) instead of seeing the first KB contain 'a's. Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org

ext4: Resolve the hang of direct i/o read in handling EXT4_IO_END_UNWRITTEN.

2011-08-13T16:30:59+00:00

EXT4_IO_END_UNWRITTEN flag set and the increase of i_aiodio_unwritten should be done simultaneously since ext4_end_io_nolock always clear the flag and decrease the counter in the same time. We don't increase i_aiodio_unwritten when setting EXT4_IO_END_UNWRITTEN so it will go nagative and causes some process to wait forever. Part of the patch came from Eric in his e-mail, but it doesn't fix the problem met by Michael actually. http://marc.info/?l=linux-ext4&m=131316851417460&w=2 Reported-and-Tested-by: Michael Tokarev Signed-off-by: Eric Sandeen Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org

ext4: call ext4_ioend_wait and ext4_flush_completed_IO in ext4_evict_inode

2011-08-13T16:17:13+00:00

Flush inode's i_completed_io_list before calling ext4_io_wait to prevent the following deadlock scenario: A page fault happens while some process is writing inode A. During page fault, shrink_icache_memory is called that in turn evicts another inode B. Inode B has some pending io_end work so it calls ext4_ioend_wait() that waits for inode B's i_ioend_count to become zero. However, inode B's ioend work was queued behind some of inode A's ioend work on the same cpu's ext4-dio-unwritten workqueue. As the ext4-dio-unwritten thread on that cpu is processing inode A's ioend work, it tries to grab inode A's i_mutex lock. Since the i_mutex lock of inode A is still hold before the page fault happened, we enter a deadlock. Also moves ext4_flush_completed_IO and ext4_ioend_wait from ext4_destroy_inode() to ext4_evict_inode(). During inode deleteion, ext4_evict_inode() is called before ext4_destroy_inode() and in ext4_evict_inode(), we may call ext4_truncate() without holding i_mutex lock. As a result, there is a race between flush_completed_IO that is called from ext4_ext_truncate() and ext4_end_io_work, which may cause corruption on an io_end structure. This change moves ext4_flush_completed_IO and ext4_ioend_wait from ext4_destroy_inode() to ext4_evict_inode() to resolve the race between ext4_truncate() and ext4_end_io_work during inode deletion. Signed-off-by: Jiaying Zhang Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org

ext4: Fix ext4_should_writeback_data() for no-journal mode

2011-08-13T15:25:18+00:00

ext4_should_writeback_data() had an incorrect sequence of tests to determine if it should return 0 or 1: in particular, even in no-journal mode, 0 was being returned for a non-regular-file inode. This meant that, in non-journal mode, we would use ext4_journalled_aops for directories, symlinks, and other non-regular files. However, calling journalled aop callbacks when there is no valid handle, can cause problems. This would cause a kernel crash with Jan Kara's commit 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data"), because we now dereference 'handle' in ext4_journalled_write_end(). I also added BUG_ONs to check for a valid handle in the obviously journal-only aops callbacks. I tested this running xfstests with a scratch device in these modes: - no-journal - data=ordered - data=writeback - data=journal All work fine; the data=journal run has many failures and a crash in xfstests 074, but this is no different from a vanilla kernel. Signed-off-by: Curt Wohlgemuth Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org

ext4: Properly count journal credits for long symlinks

2011-08-12T00:23:40+00:00

Commit df5e6223407e ("ext4: fix deadlock in ext4_symlink() in ENOSPC conditions") recalculated the number of credits needed for a long symlink, in the process of splitting it into two transactions. However, the first credit calculation under-counted because if selinux is enabled, credits are needed to create the selinux xattr as well. Overrunning the reservation will result in an OOPS in jbd2_journal_dirty_metadata() due to this assert: J_ASSERT_JH(jh, handle->h_buffer_credits > 0); Fix this by increasing the reservation size. Signed-off-by: Eric Sandeen Reviewed-by: Jan Kara Acked-by: "Theodore Ts'o" Cc: stable@kernel.org Signed-off-by: Linus Torvalds

ext4: use kzalloc in ext4_kzalloc()

2011-08-03T18:57:11+00:00

Commit 9933fc0i (ext4: introduce ext4_kvmalloc(), ext4_kzalloc(), and ext4_kvfree()) intruduced wrappers around k*alloc/vmalloc but introduced a typo for ext4_kzalloc() by not using kzalloc() but kmalloc(). Signed-off-by: Mathias Krause Signed-off-by: "Theodore Ts'o"

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2011-08-01T23:56:03+00:00

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (60 commits) ext4: prevent memory leaks from ext4_mb_init_backend() on error path ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode # ext4: use ext4_msg() instead of printk in mballoc ext4: use ext4_kvzalloc()/ext4_kvmalloc() for s_group_desc and s_group_info ext4: introduce ext4_kvmalloc(), ext4_kzalloc(), and ext4_kvfree() ext4: use the correct error exit path in ext4_init_inode_table() ext4: add missing kfree() on error return path in add_new_gdb() ext4: change umode_t in tracepoint headers to be an explicit __u16 ext4: fix races in ext4_sync_parent() ext4: Fix overflow caused by missing cast in ext4_fallocate() ext4: add action of moving index in ext4_ext_rm_idx for Punch Hole ext4: simplify parameters of reserve_backup_gdb() ext4: simplify parameters of add_new_gdb() ext4: remove lock_buffer in bclean() and setup_new_group_blocks() ext4: simplify journal handling in setup_new_group_blocks() ext4: let setup_new_group_blocks() set multiple bits at a time ext4: fix a typo in ext4_group_extend() ext4: let ext4_group_add_blocks() handle 0 blocks quickly ext4: let ext4_group_add_blocks() return an error code ext4: rename ext4_add_groupblocks() to ext4_group_add_blocks() ... Fix up conflict in fs/ext4/inode.c: commit aacfc19c626e ("fs: simplify the blockdev_direct_IO prototype") had changed the ext4_ind_direct_IO() function for the new simplified calling convention, while commit dae1e52cb126 ("ext4: move ext4_ind_* functions from inode.c to indirect.c") moved the function to another file.

ext4: prevent memory leaks from ext4_mb_init_backend() on error path

2011-08-01T21:41:46+00:00

In ext4_mb_init(), if the s_locality_group allocation fails it will currently cause the allocations made in ext4_mb_init_backend() to be leaked. Moving the ext4_mb_init_backend() allocation after the s_locality_group allocation avoids that problem. Signed-off-by: Yu Jian Signed-off-by: Andreas Dilger Signed-off-by: "Theodore Ts'o"