talos-op-linux/fs/btrfs/disk-io.h, branch master

btrfs: drop create parameter to btrfs_get_extent()

2020-01-20T15:40:55+00:00

We only pass this as 1 from __extent_writepage_io(). The parameter basically means "pretend I didn't pass in a page". This is silly since we can simply not pass in the page. Get rid of the parameter from btrfs_get_extent(), and since it's used as a get_extent_t callback, remove it from get_extent_t and btree_get_extent(), neither of which need it. While we're here, let's document btrfs_get_extent(). Signed-off-by: Omar Sandoval Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: add __cold attribute to more functions

2019-11-18T11:46:52+00:00

The attribute can mark functions supposed to be called rarely if at all and the text can be moved to sections far from the other code. The attribute has been added to several functions already, this patch is based on hints given by gcc -Wsuggest-attribute=cold. The net effect of this patch is decrease of btrfs.ko by 1000-1300, depending on the config options. Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba

btrfs: Make reada_tree_block_flagged private

2019-09-09T12:59:11+00:00

This function is used only for the readahead machinery. It makes no sense to keep it external to reada.c file. Place it above its sole caller and make it static. No functional changes. Reviewed-by: Johannes Thumshirn Signed-off-by: Nikolay Borisov Signed-off-by: David Sterba

btrfs: directly call into crypto framework for checksumming

2019-07-01T11:35:02+00:00

Currently btrfs_csum_data() relied on the crc32c() wrapper around the crypto framework for calculating the CRCs. As we have our own crypto_shash structure in the fs_info now, we can directly call into the crypto framework without going trough the wrapper. This way we can even remove the btrfs_csum_data() and btrfs_csum_final() wrappers. The module dependency on crc32c is preserved via MODULE_SOFTDEP("pre: crc32c"), which was previously provided by LIBCRC32C config option doing the same. Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: get fs_info from trans in btrfs_create_tree

2019-04-29T17:02:41+00:00

We can read fs_info from the transaction and can drop it from the parameters. Signed-off-by: David Sterba

btrfs: get fs_info from eb in btrfs_verify_level_key

2019-04-29T17:02:31+00:00

We can read fs_info from extent buffer and can drop it from the parameters. Signed-off-by: David Sterba

btrfs: get fs_info from eb in clean_tree_block

2019-04-29T17:02:30+00:00

We can read fs_info from extent buffer and can drop it from the parameters. Signed-off-by: David Sterba

btrfs: move tree block wait and write helpers to tree-log

2019-04-29T17:02:28+00:00

The wrapper names better describe what's happening so they're not deleted though they're trivial, but at least moved closer to their place of use. Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba

btrfs: Check the first key and level for cached extent buffer

2019-04-29T17:02:22+00:00

[BUG] When reading a file from a fuzzed image, kernel can panic like: BTRFS warning (device loop0): csum failed root 5 ino 270 off 0 csum 0x98f94189 expected csum 0x00000000 mirror 1 assertion failed: !memcmp_extent_buffer(b, &disk_key, offsetof(struct btrfs_leaf, items[0].key), sizeof(disk_key)), file: fs/btrfs/ctree.c, line: 2544 ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.h:3500! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:btrfs_search_slot.cold.24+0x61/0x63 [btrfs] Call Trace: btrfs_lookup_csum+0x52/0x150 [btrfs] __btrfs_lookup_bio_sums+0x209/0x640 [btrfs] btrfs_submit_bio_hook+0x103/0x170 [btrfs] submit_one_bio+0x59/0x80 [btrfs] extent_read_full_page+0x58/0x80 [btrfs] generic_file_read_iter+0x2f6/0x9d0 __vfs_read+0x14d/0x1a0 vfs_read+0x8d/0x140 ksys_read+0x52/0xc0 do_syscall_64+0x60/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe [CAUSE] The fuzzed image has a corrupted leaf whose first key doesn't match its parent: checksum tree key (CSUM_TREE ROOT_ITEM 0) node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c ... key (EXTENT_CSUM EXTENT_CSUM 79691776) block 29761536 gen 19 leaf 29761536 items 1 free space 1726 generation 19 owner CSUM_TREE leaf 29761536 flags 0x1(WRITTEN) backref revision 1 fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c item 0 key (EXTENT_CSUM EXTENT_CSUM 8798638964736) itemoff 1751 itemsize 2244 range start 8798638964736 end 8798641262592 length 2297856 When reading the above tree block, we have extent_buffer->refs = 2 in the context: - initial one from __alloc_extent_buffer() alloc_extent_buffer() |- __alloc_extent_buffer() |- atomic_set(&eb->refs, 1) - one being added to fs_info->buffer_radix alloc_extent_buffer() |- check_buffer_tree_ref() |- atomic_inc(&eb->refs) So if even we call free_extent_buffer() in read_tree_block or other similar situation, we only decrease the refs by 1, it doesn't reach 0 and won't be freed right now. The staled eb and its corrupted content will still be kept cached. Furthermore, we have several extra cases where we either don't do first key check or the check is not proper for all callers: - scrub We just don't have first key in this context. - shared tree block One tree block can be shared by several snapshot/subvolume trees. In that case, the first key check for one subvolume doesn't apply to another. So for the above reasons, a corrupted extent buffer can sneak into the buffer cache. [FIX] Call verify_level_key in read_block_for_search to do another verification. For that purpose the function is exported. Due to above reasons, although we can free corrupted extent buffer from cache, we still need the check in read_block_for_search(), for scrub and shared tree blocks. Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202757 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202759 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202761 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202767 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202769 Reported-by: Yoon Jungyeon CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: drop extra enum initialization where using defaults

2018-12-17T13:51:43+00:00

The first auto-assigned value to enum is 0, we can use that and not initialize all members where the auto-increment does the same. This is used for values that are not part of on-disk format. Reviewed-by: Omar Sandoval Reviewed-by: Qu Wenruo Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba