kernel/git/stable/linux-stable.git/fs/ocfs2/alloc.h, branch linux-5.0.y

ocfs2: try to reuse extent block in dealloc without meta_alloc

2018-02-01T01:18:35+00:00

A crash issue was reported by John Lightsey with a call trace as follows: ocfs2_split_extent+0x1ad3/0x1b40 [ocfs2] ocfs2_change_extent_flag+0x33a/0x470 [ocfs2] ocfs2_mark_extent_written+0x172/0x220 [ocfs2] ocfs2_dio_end_io+0x62d/0x910 [ocfs2] dio_complete+0x19a/0x1a0 do_blockdev_direct_IO+0x19dd/0x1eb0 __blockdev_direct_IO+0x43/0x50 ocfs2_direct_IO+0x8f/0xa0 [ocfs2] generic_file_direct_write+0xb2/0x170 __generic_file_write_iter+0xc3/0x1b0 ocfs2_file_write_iter+0x4bb/0xca0 [ocfs2] __vfs_write+0xae/0xf0 vfs_write+0xb8/0x1b0 SyS_write+0x4f/0xb0 system_call_fastpath+0x16/0x75 The BUG code told that extent tree wants to grow but no metadata was reserved ahead of time. From my investigation into this issue, the root cause it that although enough metadata is not reserved, there should be enough for following use. Rightmost extent is merged into its left one due to a certain times of marking extent written. Because during marking extent written, we got many physically continuous extents. At last, an empty extent showed up and the rightmost path is removed from extent tree. Add a new mechanism to reuse extent block cached in dealloc which were just unlinked from extent tree to solve this crash issue. Criteria is that during marking extents *written*, if extent rotation and merging results in unlinking extent with growing extent tree later without any metadata reserved ahead of time, try to reuse those extents in dealloc in which deleted extents are cached. Also, this patch addresses the issue John reported that ::dw_zero_count is not calculated properly. After applying this patch, the issue John reported was gone. Thanks for the reproducer provided by John. And this patch has passed ocfs2-test(29 cases) suite running by New H3C Group. [ge.changwei@h3c.com: fix static checker warnning] Link: http://lkml.kernel.org/r/63ADC13FD55D6546B7DECE290D39E373F29196AE@H3CMLB12-EX.srv.huawei-3com.com [akpm@linux-foundation.org: brelse(NULL) is legal] Link: http://lkml.kernel.org/r/1515479070-32653-2-git-send-email-ge.changwei@h3c.com Signed-off-by: Changwei Ge Reported-by: John Lightsey Tested-by: John Lightsey Cc: Joel Becker Cc: Joseph Qi Cc: Junxiao Bi Cc: Dan Carpenter Cc: Mark Fasheh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ocfs2: clean up some dead code

2017-09-07T00:27:24+00:00

clean up some unused functions and parameters. Link: http://lkml.kernel.org/r/598A5E21.2080807@huawei.com Signed-off-by: Jun Piao Reviewed-by: Alex Chen Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ocfs2: retry on ENOSPC if sufficient space in truncate log

2016-08-02T21:31:41+00:00

The testcase "mmaptruncate" in ocfs2 test suite always fails with ENOSPC error on small volume (say less than 10G). This testcase repeatedly performs "extend" and "truncate" on a file. Continuously, it truncates the file to 1/2 of the size, and then extends to 100% of the size. The main bitmap will quickly run out of space because the "truncate" code prevent truncate log from being flushed by ocfs2_schedule_truncate_log_flush(osb, 1), while truncate log may have cached lots of clusters. So retry to allocate after flushing truncate log when ENOSPC is returned. And we cannot reuse the deleted blocks before the transaction committed. Fortunately, we already have a function to do this - ocfs2_try_to_free_truncate_log(). Just need to remove the "static" modifier and put it into the right place. The "unlock"/"lock" code isn't elegant, but there seems to be no better option. [zren@suse.com: locking fix] Link: http://lkml.kernel.org/r/1468031546-4797-1-git-send-email-zren@suse.com Link: http://lkml.kernel.org/r/1466586469-5541-1-git-send-email-zren@suse.com Signed-off-by: Eric Ren Reviewed-by: Gang He Reviewed-by: Joseph Qi Reviewed-by: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ocfs2: constify ocfs2_extent_tree_operations structures

2016-01-15T00:00:49+00:00

The ocfs2_extent_tree_operations structures are never modified, so declare them as const. Done with the help of Coccinelle. Signed-off-by: Julia Lawall Cc: Mark Fasheh Cc: Joel Becker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ocfs2: reflink: fix slow unlink for refcounted file

2014-12-19T03:08:11+00:00

When running ocfs2 test suite multiple nodes reflink stress test, for a 4 nodes cluster, every unlink() for refcounted file needs about 700s. The slow unlink is caused by the contention of refcount tree lock since all nodes are unlink files using the same refcount tree. When the unlinking file have many extents(over 1600 in our test), most of the extents has refcounted flag set. In ocfs2_commit_truncate(), it will execute the following call trace for every extents. This means it needs get and released refcount tree lock about 1600 times. And when several nodes are do this at the same time, the performance will be very low. ocfs2_remove_btree_range() -- ocfs2_lock_refcount_tree() ---- ocfs2_refcount_lock() ------ __ocfs2_cluster_lock() ocfs2_refcount_lock() is costly, move it to ocfs2_commit_truncate() to do lock/unlock once can improve a lot performance. Signed-off-by: Junxiao Bi Cc: Wengang Reviewed-by: Mark Fasheh Cc: Joel Becker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ocfs2: Add ocfs2_trim_fs for SSD trim support.

2011-05-24T06:37:18+00:00

Add ocfs2_trim_fs to support trimming freed clusters in the volume. A range will be given and all the freed clusters greater than minlen will be discarded to the block layer. Signed-off-by: Tao Ma Signed-off-by: Joel Becker

ocfs2: Remove unused truncate function from alloc.c

2011-01-08T02:03:00+00:00

Tristan Ye has done some refactoring against our truncate process, so some functions like ocfs2_prepare_truncate and ocfs2_free_truncate_context are no use and we'd better remove them. Signed-off-by: Tao Ma Signed-off-by: Joel Becker

Merge branch 'discontig-bg' of git://oss.oracle.com/git/tma/linux-2.6 into ocfs2-merge-window

2010-05-18T23:40:42+00:00

Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.

2010-05-18T19:28:13+00:00

The original idea to pull ocfs2_find_cpos_for_left_leaf() out of alloc.c is to benefit punching-holes optimization patch, it however, can also be referred by other funcs in the future who want to do the same job. Signed-off-by: Tristan Ye Acked-by: Mark Fasheh Signed-off-by: Joel Becker

Ocfs2: Optimize ocfs2 truncate to use ocfs2_remove_btree_range() instead.

2010-05-18T19:25:10+00:00

Truncate is just a special case of punching holes(from new i_size to end), we therefore could take advantage of the existing ocfs2_remove_btree_range() to reduce the comlexity and redundancy in alloc.c. The goal here is to make truncate more generic and straightforward. Several functions only used by ocfs2_commit_truncate() will smiply be removed. ocfs2_remove_btree_range() was originally used by the hole punching code, which didn't take refcount trees into account (definitely a bug). We therefore need to change that func a bit to handle refcount trees. It must take the refcount lock, calculate and reserve blocks for refcount tree changes, and decrease refcounts at the end. We replace ocfs2_lock_allocators() here by adding a new func ocfs2_reserve_blocks_for_rec_trunc() which accepts some extra blocks to reserve. This will not hurt any other code using ocfs2_remove_btree_range() (such as dir truncate and hole punching). I merged the following steps into one patch since they may be logically doing one thing, though I know it looks a little bit fat to review. 1). Remove redundant code used by ocfs2_commit_truncate(), since we're moving to ocfs2_remove_btree_range anyway. 2). Add a new func ocfs2_reserve_blocks_for_rec_trunc() for purpose of accepting some extra blocks to reserve. 3). Change ocfs2_prepare_refcount_change_for_del() a bit to fit our needs. It's safe to do this since it's only being called by truncate. 4). Change ocfs2_remove_btree_range() a bit to take refcount case into account. 5). Finally, we change ocfs2_commit_truncate() to call ocfs2_remove_btree_range() in a proper way. The patch has been tested normally for sanity check, stress tests with heavier workload will be expected. Based on this patch, fixing the punching holes bug will be fairly easy. Signed-off-by: Tristan Ye Acked-by: Mark Fasheh Signed-off-by: Joel Becker