kernel/git/stable/linux.git/fs/btrfs/raid56.c, branch linux-5.8.y

btrfs: use struct_size to calculate size of raid hash table

2020-03-23T16:01:44+00:00

The struct_size macro does the same calculation and is safe regarding overflows. Though we're not expecting them to happen, use the helper for clarity. Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

btrfs: raid56: simplify tracking of Q stripe presence

2020-03-23T16:01:41+00:00

There are temporary variables tracking the index of P and Q stripes, but none of them is really used as such, merely for determining if the Q stripe is present. This leads to compiler warnings with -Wunused-but-set-variable and has been reported several times. fs/btrfs/raid56.c: In function ‘finish_rmw’: fs/btrfs/raid56.c:1199:6: warning: variable ‘p_stripe’ set but not used [-Wunused-but-set-variable] 1199 | int p_stripe = -1; | ^~~~~~~~ fs/btrfs/raid56.c: In function ‘finish_parity_scrub’: fs/btrfs/raid56.c:2356:6: warning: variable ‘p_stripe’ set but not used [-Wunused-but-set-variable] 2356 | int p_stripe = -1; | ^~~~~~~~ Replace the two variables with one that has a clear meaning and also get rid of the warnings. The logic that verifies that there are only 2 valid cases is unchanged. Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

btrfs: remove pointless local variable in lock_stripe_add()

2019-11-18T11:47:00+00:00

In lock_stripe_add() we're caching the bucket for the stripe hash table just for a single call to dereference the stripe hash. If we just directly call rbio_bucket() we can safe the pointless local variable. Also move the dereferencing of the stripe hash outside of the variable declaration block to not break over the 80 characters limit. Reviewed-by: Nikolay Borisov Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: raid56: reduce indentation in lock_stripe_add

2019-11-18T11:47:00+00:00

In lock_stripe_add() we're traversing the stripe hash list and check if the current list element's raid_map equals is equal to the raid bio's raid_map. If both are equal we continue processing. If we'd check for inequality instead of equality we can reduce one level of indentation. Reviewed-by: Nikolay Borisov Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: get rid of unique workqueue helper functions

2019-11-18T11:46:48+00:00

Commit 9e0af2376434 ("Btrfs: fix task hang under heavy compressed write") worked around the issue that a recycled work item could get a false dependency on the original work item due to how the workqueue code guarantees non-reentrancy. It did so by giving different work functions to different types of work. However, the fixes in the previous few patches are more complete, as they prevent a work item from being recycled at all (except for a tiny window that the kernel workqueue code handles for us). This obsoletes the previous fix, so we don't need the unique helpers for correctness. The only other reason to keep them would be so they show up in stack traces, but they always seem to be optimized to a tail call, so they don't show up anyways. So, let's just get rid of the extra indirection. While we're here, rename normal_work_helper() to the more informative btrfs_work_helper(). Reviewed-by: Nikolay Borisov Reviewed-by: Filipe Manana Signed-off-by: Omar Sandoval Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: move private raid56 definitions from ctree.h

2019-09-09T12:59:15+00:00

Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

block: remove the i argument to bio_for_each_segment_all

2019-04-30T15:26:13+00:00

We only have two callers that need the integer loop iterator, and they can easily maintain it themselves. Suggested-by: Matthew Wilcox Reviewed-by: Johannes Thumshirn Acked-by: David Sterba Reviewed-by: Hannes Reinecke Acked-by: Coly Li Reviewed-by: Matthew Wilcox Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

Merge tag 'for-5.1-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2019-03-26T17:32:13+00:00

Pull btrfs fixes from David Sterba: - fsync fixes: i_size for truncate vs fsync, dio vs buffered during snapshotting, remove complicated but incomplete assertion - removed excessive warnigs, misreported device stats updates - fix raid56 page mapping for 32bit arch - fixes reported by static analyzer * tag 'for-5.1-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix assertion failure on fsync with NO_HOLES enabled btrfs: Avoid possible qgroup_rsv_size overflow in btrfs_calculate_inode_block_rsv_size btrfs: Fix bound checking in qgroup_trace_new_subtree_blocks btrfs: raid56: properly unmap parity page in finish_parity_scrub() btrfs: don't report readahead errors and don't update statistics Btrfs: fix file corruption after snapshotting due to mix of buffered/DIO writes btrfs: remove WARN_ON in log_dir_items Btrfs: fix incorrect file size after shrinking truncate and fsync

btrfs: raid56: properly unmap parity page in finish_parity_scrub()

2019-03-18T18:47:36+00:00

Parity page is incorrectly unmapped in finish_parity_scrub(), triggering a reference counter bug on i386, i.e.: [ 157.662401] kernel BUG at mm/highmem.c:349! [ 157.666725] invalid opcode: 0000 [#1] SMP PTI The reason is that kunmap(p_page) was completely left out, so we never did an unmap for the p_page and the loop unmapping the rbio page was iterating over the wrong number of stripes: unmapping should be done with nr_data instead of rbio->real_stripes. Test case to reproduce the bug: - create a raid5 btrfs filesystem: # mkfs.btrfs -m raid5 -d raid5 /dev/sdb /dev/sdc /dev/sdd /dev/sde - mount it: # mount /dev/sdb /mnt - run btrfs scrub in a loop: # while :; do btrfs scrub start -BR /mnt; done BugLink: https://bugs.launchpad.net/bugs/1812845 Fixes: 5a6ac9eacb49 ("Btrfs, raid56: support parity scrub on raid56") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn Signed-off-by: Andrea Righi Reviewed-by: David Sterba Signed-off-by: David Sterba

block: allow bio_for_each_segment_all() to iterate over multi-page bvec

2019-02-15T15:40:11+00:00

This patch introduces one extra iterator variable to bio_for_each_segment_all(), then we can allow bio_for_each_segment_all() to iterate over multi-page bvec. Given it is just one mechannical & simple change on all bio_for_each_segment_all() users, this patch does tree-wide change in one single patch, so that we can avoid to use a temporary helper for this conversion. Reviewed-by: Omar Sandoval Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei Signed-off-by: Jens Axboe