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path: root/fs/btrfs/compression.c
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2022-01-07btrfs: remove unnecessary parameter type from compression_decompress_bioSu Yue
btrfs_decompress_bio, the only caller of compression_decompress_bio gets type from @cb and passes it to compression_decompress_bio. However, compression_decompress_bio can get compression type directly from @cb. So remove the parameter and access it through @cb. No functional change. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Su Yue <l@damenly.su> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03btrfs: set BTRFS_FS_STATE_NO_CSUMS if we fail to load the csum rootJosef Bacik
We have a few places where we skip doing csums if we mounted with one of the rescue options that ignores bad csum roots. In the future when there are multiple csum roots it'll be costly to check and see if there are any missing csum roots, so simply add a flag to indicate the fs should skip loading csums in case of errors. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-11-01Merge tag 'for-5.16-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "The updates this time are more under the hood and enhancing existing features (subpage with compression and zoned namespaces). Performance related: - misc small inode logging improvements (+3% throughput, -11% latency on sample dbench workload) - more efficient directory logging: bulk item insertion, less tree searches and locking - speed up bulk insertion of items into a b-tree, which is used when logging directories, when running delayed items for directories (fsync and transaction commits) and when running the slow path (full sync) of an fsync (bulk creation run time -4%, deletion -12%) Core: - continued subpage support - make defragmentation work - make compression write work - zoned mode - support ZNS (zoned namespaces), zone capacity is number of usable blocks in each zone - add dedicated block group (zoned) for relocation, to prevent out of order writes in some cases - greedy block group reclaim, pick the ones with least usable space first - preparatory work for send protocol updates - error handling improvements - cleanups and refactoring Fixes: - lockdep warnings - in show_devname callback, on seeding device - device delete on loop device due to conversions to workqueues - fix deadlock between chunk allocation and chunk btree modifications - fix tracking of missing device count and status" * tag 'for-5.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (140 commits) btrfs: remove root argument from check_item_in_log() btrfs: remove root argument from add_link() btrfs: remove root argument from btrfs_unlink_inode() btrfs: remove root argument from drop_one_dir_item() btrfs: clear MISSING device status bit in btrfs_close_one_device btrfs: call btrfs_check_rw_degradable only if there is a missing device btrfs: send: prepare for v2 protocol btrfs: fix comment about sector sizes supported in 64K systems btrfs: update device path inode time instead of bd_inode fs: export an inode_update_time helper btrfs: fix deadlock when defragging transparent huge pages btrfs: sysfs: convert scnprintf and snprintf to sysfs_emit btrfs: make btrfs_super_block size match BTRFS_SUPER_INFO_SIZE btrfs: update comments for chunk allocation -ENOSPC cases btrfs: fix deadlock between chunk allocation and chunk btree modifications btrfs: zoned: use greedy gc for auto reclaim btrfs: check-integrity: stop storing the block device name in btrfsic_dev_state btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls btrfs: add a btrfs_get_dev_args_from_path helper btrfs: handle device lookup with btrfs_dev_lookup_args ...
2021-11-01Merge tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: - mq-deadline accounting improvements (Bart) - blk-wbt timer fix (Andrea) - Untangle the block layer includes (Christoph) - Rework the poll support to be bio based, which will enable adding support for polling for bio based drivers (Christoph) - Block layer core support for multi-actuator drives (Damien) - blk-crypto improvements (Eric) - Batched tag allocation support (me) - Request completion batching support (me) - Plugging improvements (me) - Shared tag set improvements (John) - Concurrent queue quiesce support (Ming) - Cache bdev in ->private_data for block devices (Pavel) - bdev dio improvements (Pavel) - Block device invalidation and block size improvements (Xie) - Various cleanups, fixes, and improvements (Christoph, Jackie, Masahira, Tejun, Yu, Pavel, Zheng, me) * tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block: (174 commits) blk-mq-debugfs: Show active requests per queue for shared tags block: improve readability of blk_mq_end_request_batch() virtio-blk: Use blk_validate_block_size() to validate block size loop: Use blk_validate_block_size() to validate block size nbd: Use blk_validate_block_size() to validate block size block: Add a helper to validate the block size block: re-flow blk_mq_rq_ctx_init() block: prefetch request to be initialized block: pass in blk_mq_tags to blk_mq_rq_ctx_init() block: add rq_flags to struct blk_mq_alloc_data block: add async version of bio_set_polled block: kill DIO_MULTI_BIO block: kill unused polling bits in __blkdev_direct_IO() block: avoid extra iter advance with async iocb block: Add independent access ranges support blk-mq: don't issue request directly in case that current is to be blocked sbitmap: silence data race warning blk-cgroup: synchronize blkg creation against policy deactivation block: refactor bio_iov_bvec_set() block: add single bio async direct IO helper ...
2021-10-27Revert "btrfs: compression: drop kmap/kunmap from generic helpers"David Sterba
This reverts commit 4c2bf276b56d8d27ddbafcdf056ef3fc60ae50b0. The kmaps in compression code are still needed and cause crashes on 32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004 with enabled LZO or ZSTD compression. Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839 Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: subpage: make end_compressed_bio_writeback() compatibleQu Wenruo
In end_compressed_writeback() we just clear the full page writeback. For subpage case, if there are two delalloc ranges in the same page, the 2nd range will trigger a BUG_ON() as the page writeback is already cleared by previous range. Fix it by using btrfs_page_clamp_clear_writeback() helper. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: subpage: make btrfs_submit_compressed_write() compatibleQu Wenruo
There is a WARN_ON() checking if @start is aligned to PAGE_SIZE, not sectorsize, which will cause false alert for subpage. Fix it to check against sectorsize. Furthermore: - Use ASSERT() to do the check So that in the future we may skip the check for production build - Also check alignment for @len Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: determine stripe boundary at bio allocation time in ↵Qu Wenruo
btrfs_submit_compressed_write Currently btrfs_submit_compressed_write() will check btrfs_bio_fits_in_stripe() each time a new page is going to be added. Even if compressed extent is small, we don't really need to do that for every page. Align the behavior to extent_io.c, by determining the stripe boundary when allocating a bio. Unlike extent_io.c, in compressed.c we don't need to bother things like different bio flags, thus no need to re-use bio_ctrl. Here we just manually introduce new local variable, next_stripe_start, and use that value returned from alloc_compressed_bio() to calculate the stripe boundary. Then each time we add some page range into the bio, we check if we reached the boundary. And if reached, submit it. Also, since we have @cur_disk_bytenr to determine whether we're the last bio, we don't need a explicit last_bio: tag for error handling any more. And since we use @cur_disk_bytenr to wait, there is no need for pending_bios, also remove it to save some memory of compressed_bio. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: determine stripe boundary at bio allocation time in ↵Qu Wenruo
btrfs_submit_compressed_read Currently btrfs_submit_compressed_read() will check btrfs_bio_fits_in_stripe() each time a new page is going to be added. Even if compressed extent is small, we don't really need to do that for every page. This patch will align the behavior to extent_io.c, by determining the stripe boundary when allocating a bio. Unlike extent_io.c, in compressed.c we don't need to bother things like different bio flags, thus no need to re-use bio_ctrl. Here we just manually introduce new local variable, next_stripe_start, and teach alloc_compressed_bio() to calculate the stripe boundary. Then each time we add some page range into the bio, we check if we reached the boundary. And if reached, submit it. Also, since we have @cur_disk_byte to determine whether we're the last bio, we don't need a explicit last_bio: tag for error handling any more. And we can use @cur_disk_byte to track which range has been added to bio, we can also use @cur_disk_byte to calculate the wait condition, no need for @pending_bios. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: introduce alloc_compressed_bio() for compressionQu Wenruo
Just aggregate the bio allocation code into one helper, so that we can replace 4 call sites. There is one special note for zoned write. Currently btrfs_submit_compressed_write() will only allocate the first bio using ZONE_APPEND. If we have to submit current bio due to stripe boundary, the new bio allocated will not use ZONE_APPEND. In theory this should be a bug, but considering zoned mode currently only support SINGLE profile, which doesn't have any stripe boundary limit, it should never be a problem and we have assertions in place. This function will provide a good entrance for any work which needs to be done at bio allocation time. Like determining the stripe boundary. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: introduce submit_compressed_bio() for compressionQu Wenruo
The new helper, submit_compressed_bio(), will aggregate the following work: - Increase compressed_bio::pending_bios - Remap the endio function - Map and submit the bio This slightly reorders calls to btrfs_csum_one_bio or btrfs_lookup_bio_sums but but none of them does anything regarding IO submission so this is effectively no change. We mainly care about order of - atomic_inc - btrfs_bio_wq_end_io - btrfs_map_bio Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: handle errors properly inside btrfs_submit_compressed_write()Qu Wenruo
Just like btrfs_submit_compressed_read(), there are quite some BUG_ON()s inside btrfs_submit_compressed_write() for the bio submission path. Fix them using the same method: - For last bio, just endio the bio As in that case, one of the endio function of all these submitted bio will be able to free the compressed_bio - For half-submitted bio, wait and finish the compressed_bio manually In this case, as long as all other bio finish, we're the only one referring the compressed bio, and can manually finish it. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: handle errors properly inside btrfs_submit_compressed_read()Qu Wenruo
There are quite some BUG_ON()s inside btrfs_submit_compressed_read(), namely all errors inside the for() loop relies on BUG_ON() to handle -ENOMEM. Handle these errors properly by: - Wait for submitted bios to finish first Using wake_var_event() APIs to wait without introducing extra memory overhead inside compressed_bio. This allows us to wait for any submitted bio to finish, while still keeps the compressed_bio from being freed. - Introduce finish_compressed_bio_read() to finish the compressed_bio - Properly end the bio and finish compressed_bio when error happens Now in btrfs_submit_compressed_read() even when the bio submission failed, we can properly handle the error without triggering BUG_ON(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: subpage: add bitmap for PageChecked flagQu Wenruo
Although in btrfs we have very limited usage of PageChecked flag, it's still some page flag not yet subpage compatible. Fix it by introducing btrfs_subpage::checked_offset to do the convert. For most call sites, especially for free-space cache, COW fixup and btrfs_invalidatepage(), they all work in full page mode anyway. For other call sites, they work as subpage compatible mode. Some call sites need extra modification: - btrfs_drop_pages() Needs extra parameter to get the real range we need to clear checked flag. Also since btrfs_drop_pages() will accept pages beyond the dirtied range, update btrfs_subpage_clamp_range() to handle such case by setting @len to 0 if the page is beyond target range. - btrfs_invalidatepage() We need to call subpage helper before calling __btrfs_releasepage(), or it will trigger ASSERT() as page->private will be cleared. - btrfs_verify_data_csum() In theory we don't need the io_bio->csum check anymore, but it's won't hurt. Just change the comment. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: introduce compressed_bio::pending_sectors to trace compressed bioQu Wenruo
For btrfs_submit_compressed_read() and btrfs_submit_compressed_write(), we have a pretty weird dance around compressed_bio::pending_bios: btrfs_submit_compressed_read/write() { cb = kmalloc() refcount_set(&cb->pending_bios, 0); bio = btrfs_alloc_bio(); /* NOTE here, we haven't yet submitted any bio */ refcount_set(&cb->pending_bios, 1); for (pg_index = 0; pg_index < cb->nr_pages; pg_index++) { if (submit) { /* Here we submit bio, but we always have one * extra pending_bios */ refcount_inc(&cb->pending_bios); ret = btrfs_map_bio(); } } /* Submit the last bio */ ret = btrfs_map_bio(); } There are two reasons why we do this: - compressed_bio::pending_bios is a refcount Thus if it's reduced to 0, it can not be increased again. - To ensure the compressed_bio is not freed by some submitted bios If the submitted bio is finished before the next bio submitted, we can free the compressed_bio completely. But the above code is sometimes confusing, and we can do it better by introducing a new member, compressed_bio::pending_sectors. Now we use compressed_bio::pending_sectors to indicate whether we have any pending sectors under IO or not yet submitted. If pending_sectors == 0, we're definitely the last bio of compressed_bio, and is OK to release the compressed bio. Now the workflow looks like this: btrfs_submit_compressed_read/write() { cb = kmalloc() atomic_set(&cb->pending_bios, 0); refcount_set(&cb->pending_sectors, compressed_len >> sectorsize_bits); bio = btrfs_alloc_bio(); for (pg_index = 0; pg_index < cb->nr_pages; pg_index++) { if (submit) { refcount_inc(&cb->pending_bios); ret = btrfs_map_bio(); } } /* Submit the last bio */ refcount_inc(&cb->pending_bios); ret = btrfs_map_bio(); } For now we still need pending_bios for later error handling, but will remove pending_bios eventually after properly handling the errors. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: subpage: make add_ra_bio_pages() compatibleQu Wenruo
[BUG] If we remove the subpage limitation in add_ra_bio_pages(), then read a compressed extent which has part of its range in next page, like the following inode layout: 0 32K 64K 96K 128K |<--------------|-------------->| Btrfs will trigger ASSERT() in endio function: assertion failed: atomic_read(&subpage->readers) >= nbits ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.h:3431! Internal error: Oops - BUG: 0 [#1] SMP Workqueue: btrfs-endio btrfs_work_helper [btrfs] Call trace: assertfail.constprop.0+0x28/0x2c [btrfs] btrfs_subpage_end_reader+0x148/0x14c [btrfs] end_page_read+0x8c/0x100 [btrfs] end_bio_extent_readpage+0x320/0x6b0 [btrfs] bio_endio+0x15c/0x1dc end_workqueue_fn+0x44/0x64 [btrfs] btrfs_work_helper+0x74/0x250 [btrfs] process_one_work+0x1d4/0x47c worker_thread+0x180/0x400 kthread+0x11c/0x120 ret_from_fork+0x10/0x30 ---[ end trace c8b7b552d3bb408c ]--- [CAUSE] When we read the page range [0, 64K), we find it's a compressed extent, and we will try to add extra pages in add_ra_bio_pages() to avoid reading the same compressed extent. But when we add such page into the read bio, it doesn't follow the behavior of btrfs_do_readpage() to properly set subpage::readers. This means, for page [64K, 128K), its subpage::readers is still 0. And when endio is executed on both pages, since page [64K, 128K) has 0 subpage::readers, it triggers above ASSERT() [FIX] Function add_ra_bio_pages() is far from subpage compatible, it always assume PAGE_SIZE == sectorsize, thus when it skip to next range it always just skip PAGE_SIZE. Make it subpage compatible by: - Skip to next page properly when needed If we find there is already a page cache, we need to skip to next page. For that case, we shouldn't just skip PAGE_SIZE bytes, but use @pg_index to calculate the next bytenr and continue. - Only add the page range covered by current extent map We need to calculate which range is covered by current extent map and only add that part into the read bio. - Update subpage::readers before submitting the bio - Use proper cursor other than confusing @last_offset - Calculate the missed threshold based on sector size It's no longer using missed pages, as for 64K page size, we have at most 3 pages to skip. (If aligned only 2 pages) - Add ASSERT() to make sure our bytenr is always aligned - Add comment for the function Add a special note for subpage case, as the function won't really work well for subpage cases. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: remove unused parameter nr_pages in add_ra_bio_pages()Qu Wenruo
Variable @nr_pages only gets increased but never used. Remove it. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: rename struct btrfs_io_bio to btrfs_bioQu Wenruo
Previously we had "struct btrfs_bio", which records IO context for mirrored IO and RAID56, and "strcut btrfs_io_bio", which records extra btrfs specific info for logical bytenr bio. With "btrfs_bio" renamed to "btrfs_io_context", we are safe to rename "btrfs_io_bio" to "btrfs_bio" which is a more suitable name now. The struct btrfs_bio changes meaning by this commit. There was a suggested name like btrfs_logical_bio but it's a bit long and we'd prefer to use a shorter name. This could be a concern for backports to older kernels where the different meaning could possibly cause confusion or bugs. Comparing the new and old structures, there's no overlap among the struct members so a build would break in case of incorrect backport. We haven't had many backports to bio code anyway so this is more of a theoretical cause of bugs and a matter of precaution but we'll need to keep the semantic change in mind. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: remove btrfs_bio_alloc() helperQu Wenruo
The helper btrfs_bio_alloc() is almost the same as btrfs_io_bio_alloc(), except it's allocating using BIO_MAX_VECS as @nr_iovecs, and initializes bio->bi_iter.bi_sector. However the naming itself is not using "btrfs_io_bio" to indicate its parameter is "strcut btrfs_io_bio" and can be easily confused with "struct btrfs_bio". Considering assigned bio->bi_iter.bi_sector is such a simple work and there are already tons of call sites doing that manually, there is no need to do that in a helper. Remove btrfs_bio_alloc() helper, and enhance btrfs_io_bio_alloc() function to provide a fail-safe value for its @nr_iovecs. And then replace all btrfs_bio_alloc() callers with btrfs_io_bio_alloc(). Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-18mm: don't include <linux/blk-cgroup.h> in <linux/backing-dev.h>Christoph Hellwig
There is no need to pull blk-cgroup.h and thus blkdev.h in here, so break the include chain. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210920123328.1399408-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-23btrfs: rework btrfs_decompress_buf2page()Qu Wenruo
There are several bugs inside the function btrfs_decompress_buf2page() - @start_byte doesn't take bvec.bv_offset into consideration Thus it can't handle case where the target range is not page aligned. - Too many helper variables There are tons of helper variables, @buf_offset, @current_buf_start, @start_byte, @prev_start_byte, @working_bytes, @bytes. This hurts anyone who wants to read the function. - No obvious main cursor for the iteartion A new problem caused by previous problem. - Comments for parameter list makes no sense Like @buf_start is the offset to @buf, or offset inside the full decompressed extent? (Spoiler alert, the later case) And @total_out acts more like @buf_start + @size_of_buf. The worst is @disk_start. The real meaning of it is the file offset of the full decompressed extent. This patch will rework the whole function by: - Add a proper comment with ASCII art to explain the parameter list - Rework parameter list The old @buf_start is renamed to @decompressed, to show how many bytes are already decompressed inside the full decompressed extent. The old @total_out is replaced by @buf_len, which is the decompressed data size. For old @disk_start and @bio, just pass @compressed_bio in. - Use single main cursor The main cursor will be @cur_file_offset, to show what's the current file offset. Other helper variables will be declared inside the main loop, and only minimal amount of helper variables: * offset_inside_decompressed_buf: The only real helper * copy_start_file_offset: File offset we start memcpy * bvec_file_offset: File offset of current bvec Even with all these extensive comments, the final function is still smaller than the original function, which is definitely a win. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: grab correct extent map for subpage compressed extent readQu Wenruo
[BUG] When subpage compressed read write support is enabled, btrfs/038 always fails with EIO. A simplified script can easily trigger the problem: mkfs.btrfs -f -s 4k $dev mount $dev $mnt -o compress=lzo xfs_io -f -c "truncate 118811" $mnt/foo xfs_io -c "pwrite -S 0x0d -b 39987 92267 39987" $mnt/foo > /dev/null sync btrfs subvolume snapshot -r $mnt $mnt/mysnap1 xfs_io -c "pwrite -S 0x3e -b 80000 200000 80000" $mnt/foo > /dev/null sync xfs_io -c "pwrite -S 0xdc -b 10000 250000 10000" $mnt/foo > /dev/null xfs_io -c "pwrite -S 0xff -b 10000 300000 10000" $mnt/foo > /dev/null sync btrfs subvolume snapshot -r $mnt $mnt/mysnap2 cat $mnt/mysnap2/foo # Above cat will fail due to EIO [CAUSE] The problem is in btrfs_submit_compressed_read(). When it tries to grab the extent map of the read range, it uses the following call: em = lookup_extent_mapping(em_tree, page_offset(bio_first_page_all(bio)), fs_info->sectorsize); The problem is in the page_offset(bio_first_page_all(bio)) part. The offending inode has the following file extent layout item 10 key (257 EXTENT_DATA 131072) itemoff 15639 itemsize 53 generation 8 type 1 (regular) extent data disk byte 13680640 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) item 11 key (257 EXTENT_DATA 135168) itemoff 15586 itemsize 53 generation 8 type 1 (regular) extent data disk byte 0 nr 0 item 12 key (257 EXTENT_DATA 196608) itemoff 15533 itemsize 53 generation 8 type 1 (regular) extent data disk byte 13676544 nr 4096 extent data offset 0 nr 53248 ram 86016 extent compression 2 (lzo) And the bio passed in has the following parameters: page_offset(bio_first_page_all(bio)) = 131072 bio_first_bvec_all(bio)->bv_offset = 65536 If we use page_offset(bio_first_page_all(bio) without adding bv_offset, we will get an extent map for file offset 131072, not 196608. This means we read uncompressed data from disk, and later decompression will definitely fail. [FIX] Take bv_offset into consideration when trying to grab an extent map. And add an ASSERT() to ensure we're really getting a compressed extent. Thankfully this won't affect anything but subpage, thus we only need to ensure this patch get merged before we enabled basic subpage support. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: disable compressed readahead for subpageQu Wenruo
For current subpage support, we only support 64K page size with 4K sector size. This makes compressed readahead less effective, as maximum compressed extent size is only 128K, 2x the page size. On the other hand, the function add_ra_bio_pages() is still assuming sectorsize == PAGE_SIZE, and code change may affect 4K page size systems. So for now, let's disable subpage compressed readahead for now. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: compression: drop kmap/kunmap from generic helpersDavid Sterba
The pages in compressed_pages are not from highmem anymore so we can drop the mapping for checksum calculation and inline extent. Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: drop from __GFP_HIGHMEM all allocationsDavid Sterba
The highmem flag is used for allocating pages for compression and for raid56 pages. The high memory makes sense on 32bit systems but is not without problems. On 64bit system's it's just another layer of wrappers. The time the pages are allocated for compression or raid56 is relatively short (about a transaction commit), so the pages are not blocked indefinitely. As the number of pages depends on the amount of data being written/read, there's a theoretical problem. A fast device on a 32bit system could use most of the low memory pool, while with the highmem allocation that would not happen. This was possibly the original idea long time ago, but nowadays we optimize for 64bit systems. This patch removes all usage of the __GFP_HIGHMEM flag for page allocation, the kmap/kunmap are still in place and will be removed in followup patches. Remaining is masking out the bit in alloc_extent_state and __lookup_free_space_inode, that can safely stay. Signed-off-by: David Sterba <dsterba@suse.com>
2021-07-28btrfs: mark compressed range uptodate only if all bio succeedGoldwyn Rodrigues
In compression write endio sequence, the range which the compressed_bio writes is marked as uptodate if the last bio of the compressed (sub)bios is completed successfully. There could be previous bio which may have failed which is recorded in cb->errors. Set the writeback range as uptodate only if cb->errors is zero, as opposed to checking only the last bio's status. Backporting notes: in all versions up to 4.4 the last argument is always replaced by "!cb->errors". CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22btrfs: remove a stale comment for btrfs_decompress_bio()Qu Wenruo
Since commit 8140dc30a432 ("btrfs: btrfs_decompress_bio() could accept compressed_bio instead"), btrfs_decompress_bio() accepts "struct compressed_bio" other than open-coded parameter list. Thus the comments for the parameter list is no longer needed. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: pass btrfs_inode to btrfs_writepage_endio_finish_ordered()Qu Wenruo
There is a pretty bad abuse of btrfs_writepage_endio_finish_ordered() in end_compressed_bio_write(). It passes compressed pages to btrfs_writepage_endio_finish_ordered(), which is only supposed to accept inode pages. Thankfully the important info here is the inode, so let's pass btrfs_inode directly into btrfs_writepage_endio_finish_ordered(), and make @page parameter optional. By this, end_compressed_bio_write() can happily pass page=NULL while still getting everything done properly. Also, to cooperate with such modification, replace @page parameter for trace_btrfs_writepage_end_io_hook() with btrfs_inode. Although this removes page_index info, the existing start/len should be enough for most usage. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: fix comment about max_out in btrfs_compress_pagesAnand Jain
Commit e5d74902362f ("btrfs: derive maximum output size in the compression implementation") removed @max_out argument in btrfs_compress_pages() but its comment remained, remove it. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: optimize variables size in btrfs_submit_compressed_writeAnand Jain
Patch "btrfs: reduce compressed_bio member's types" reduced some member's size. Function arguments @len, @compressed_len and @nr_pages can be declared as unsigned int. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: optimize variables size in btrfs_submit_compressed_readAnand Jain
Patch "btrfs: reduce compressed_bio member's types" reduced some member's size. Declare the variables @compressed_len, @nr_pages and @pg_index size as an unsigned int in the function btrfs_submit_compressed_read. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: reduce the variable size to fit nr_pagesAnand Jain
Patch "btrfs: reduce compressed_bio member's types" reduced the @nr_pages size to unsigned int, its cascading effects are updated here. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: reduce compressed_bio members' typesDavid Sterba
Several members of compressed_bio are of type that's unnecessarily big for the values that they'd hold: - the size of the uncompressed and compressed data is 128K now, we can keep is as int - same for number of pages - the compress type fits to a byte - the errors is 0/1 The size of the unpatched structure is 80 bytes with several holes. Reordering nr_pages next to the pages the hole after pending_bios is filled and the resulting size is 56 bytes. This keeps the csums array aligned to 8 bytes, which is nice. Further size optimizations may be possible but right now it looks good to me: struct compressed_bio { refcount_t pending_bios; /* 0 4 */ unsigned int nr_pages; /* 4 4 */ struct page * * compressed_pages; /* 8 8 */ struct inode * inode; /* 16 8 */ u64 start; /* 24 8 */ unsigned int len; /* 32 4 */ unsigned int compressed_len; /* 36 4 */ u8 compress_type; /* 40 1 */ u8 errors; /* 41 1 */ /* XXX 2 bytes hole, try to pack */ int mirror_num; /* 44 4 */ struct bio * orig_bio; /* 48 8 */ u8 sums[]; /* 56 0 */ /* size: 56, cachelines: 1, members: 12 */ /* sum members: 54, holes: 1, sum holes: 2 */ /* last cacheline: 56 bytes */ }; Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: zoned: factor out zoned device lookupJohannes Thumshirn
To be able to construct a zone append bio we need to look up the btrfs_device. The code doing the chunk map lookup to get the device is present in btrfs_submit_compressed_write and submit_extent_page. Factor out the lookup calls into a helper and use it in the submission paths. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-03Merge tag 'for-5.13-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Error handling improvements, caught by error injection: - handle errors during checksum deletion - set error on mapping when ordered extent io cannot be finished - inode link count fixup in tree-log - missing return value checks for inode updates in tree-log - abort transaction in rename exchange if adding second reference fails Fixes: - fix fsync failure after writes to prealloc extents - fix deadlock when cloning inline extents and low on available space - fix compressed writes that cross stripe boundary" * tag 'for-5.13-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: MAINTAINERS: add btrfs IRC link btrfs: fix deadlock when cloning inline extents and low on available space btrfs: fix fsync failure and transaction abort after writes to prealloc extents btrfs: abort in rename_exchange if we fail to insert the second ref btrfs: check error value from btrfs_update_inode in tree log btrfs: fixup error handling in fixup_inode_link_counts btrfs: mark ordered extent and inode with error if we fail to finish btrfs: return errors from btrfs_del_csums in cleanup_ref_head btrfs: fix error handling in btrfs_del_csums btrfs: fix compressed writes that cross stripe boundary
2021-05-27btrfs: fix compressed writes that cross stripe boundaryQu Wenruo
[BUG] When running btrfs/027 with "-o compress" mount option, it always crashes with the following call trace: BTRFS critical (device dm-4): mapping failed logical 298901504 bio len 12288 len 8192 ------------[ cut here ]------------ kernel BUG at fs/btrfs/volumes.c:6651! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 5 PID: 31089 Comm: kworker/u24:10 Tainted: G OE 5.13.0-rc2-custom+ #26 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: btrfs-delalloc btrfs_work_helper [btrfs] RIP: 0010:btrfs_map_bio.cold+0x58/0x5a [btrfs] Call Trace: btrfs_submit_compressed_write+0x2d7/0x470 [btrfs] submit_compressed_extents+0x3b0/0x470 [btrfs] ? mark_held_locks+0x49/0x70 btrfs_work_helper+0x131/0x3e0 [btrfs] process_one_work+0x28f/0x5d0 worker_thread+0x55/0x3c0 ? process_one_work+0x5d0/0x5d0 kthread+0x141/0x160 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x22/0x30 ---[ end trace 63113a3a91f34e68 ]--- [CAUSE] The critical message before the crash means we have a bio at logical bytenr 298901504 length 12288, but only 8192 bytes can fit into one stripe, the remaining 4096 bytes go to another stripe. In btrfs, all bios are properly split to avoid cross stripe boundary, but commit 764c7c9a464b ("btrfs: zoned: fix parallel compressed writes") changed the behavior for compressed writes. Previously if we find our new page can't be fitted into current stripe, ie. "submit == 1" case, we submit current bio without adding current page. submit = btrfs_bio_fits_in_stripe(page, PAGE_SIZE, bio, 0); page->mapping = NULL; if (submit || bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { But after the modification, we will add the page no matter if it crosses stripe boundary, leading to the above crash. submit = btrfs_bio_fits_in_stripe(page, PAGE_SIZE, bio, 0); if (pg_index == 0 && use_append) len = bio_add_zone_append_page(bio, page, PAGE_SIZE, 0); else len = bio_add_page(bio, page, PAGE_SIZE, 0); page->mapping = NULL; if (submit || len < PAGE_SIZE) { [FIX] It's no longer possible to revert to the original code style as we have two different bio_add_*_page() calls now. The new fix is to skip the bio_add_*_page() call if @submit is true. Also to avoid @len to be uninitialized, always initialize it to zero. If @submit is true, @len will not be checked. If @submit is not true, @len will be the return value of bio_add_*_page() call. Either way, the behavior is still the same as the old code. Reported-by: Josef Bacik <josef@toxicpanda.com> Fixes: 764c7c9a464b ("btrfs: zoned: fix parallel compressed writes") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-21Merge tag 'for-5.13-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more fixes: - fix unaligned compressed writes in zoned mode - fix false positive lockdep warning when cloning inline extent - remove wrong BUG_ON in tree-log error handling" * tag 'for-5.13-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: zoned: fix parallel compressed writes btrfs: zoned: pass start block to btrfs_use_zone_append btrfs: do not BUG_ON in link_to_fixup_dir btrfs: release path before starting transaction when cloning inline extent
2021-05-20btrfs: zoned: fix parallel compressed writesJohannes Thumshirn
When multiple processes write data to the same block group on a compressed zoned filesystem, the underlying device could report I/O errors and data corruption is possible. This happens because on a zoned file system, compressed data writes where sent to the device via a REQ_OP_WRITE instead of a REQ_OP_ZONE_APPEND operation. But with REQ_OP_WRITE and parallel submission it cannot be guaranteed that the data is always submitted aligned to the underlying zone's write pointer. The change to using REQ_OP_ZONE_APPEND instead of REQ_OP_WRITE on a zoned filesystem is non intrusive on a regular file system or when submitting to a conventional zone on a zoned filesystem, as it is guarded by btrfs_use_zone_append. Reported-by: David Sterba <dsterba@suse.com> Fixes: 9d294a685fbc ("btrfs: zoned: enable to mount ZONED incompat flag") CC: stable@vger.kernel.org # 5.12.x: e380adfc213a13: btrfs: zoned: pass start block to btrfs_use_zone_append CC: stable@vger.kernel.org # 5.12.x Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-05btrfs: use memzero_page() instead of open coded kmap patternIra Weiny
There are many places where kmap/memset/kunmap patterns occur. Use the newly lifted memzero_page() to eliminate direct uses of kmap and leverage the new core functions use of kmap_local_page(). The development of this patch was aided by the following coccinelle script: // <smpl> // SPDX-License-Identifier: GPL-2.0-only // Find kmap/memset/kunmap pattern and replace with memset*page calls // // NOTE: Offsets and other expressions may be more complex than what the script // will automatically generate. Therefore a catchall rule is provided to find // the pattern which then must be evaluated by hand. // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ // Comments: // Options: // // Then the memset pattern // @ memset_rule1 @ expression page, V, L, Off; identifier ptr; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( -memset(ptr, 0, L); +memzero_page(page, 0, L); | -memset(ptr + Off, 0, L); +memzero_page(page, Off, L); | -memset(ptr, V, L); +memset_page(page, V, 0, L); | -memset(ptr + Off, V, L); +memset_page(page, V, Off, L); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule1 @ identifier memset_rule1.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // // Catch all // @ memset_rule2 @ expression page; identifier ptr; expression GenTo, GenSize, GenValue; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( // // Some call sites have complex expressions within the memset/memcpy // The follow are catch alls which need to be evaluated by hand. // -memset(GenTo, 0, GenSize); +memzero_pageExtra(page, GenTo, GenSize); | -memset(GenTo, GenValue, GenSize); +memset_pageExtra(page, GenValue, GenTo, GenSize); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule2 @ identifier memset_rule2.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // </smpl> Link: https://lkml.kernel.org/r/20210309212137.2610186-4-ira.weiny@intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: David Sterba <dsterba@suse.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-19btrfs: handle remount to no compress during compressionQu Wenruo
[BUG] When running btrfs/071 with inode_need_compress() removed from compress_file_range(), we got the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Workqueue: btrfs-delalloc btrfs_work_helper [btrfs] RIP: 0010:compress_file_range+0x476/0x7b0 [btrfs] Call Trace: ? submit_compressed_extents+0x450/0x450 [btrfs] async_cow_start+0x16/0x40 [btrfs] btrfs_work_helper+0xf2/0x3e0 [btrfs] process_one_work+0x278/0x5e0 worker_thread+0x55/0x400 ? process_one_work+0x5e0/0x5e0 kthread+0x168/0x190 ? kthread_create_worker_on_cpu+0x70/0x70 ret_from_fork+0x22/0x30 ---[ end trace 65faf4eae941fa7d ]--- This is already after the patch "btrfs: inode: fix NULL pointer dereference if inode doesn't need compression." [CAUSE] @pages is firstly created by kcalloc() in compress_file_extent(): pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); Then passed to btrfs_compress_pages() to be utilized there: ret = btrfs_compress_pages(... pages, &nr_pages, ...); btrfs_compress_pages() will initialize each page as output, in zlib_compress_pages() we have: pages[nr_pages] = out_page; nr_pages++; Normally this is completely fine, but there is a special case which is in btrfs_compress_pages() itself: switch (type) { default: return -E2BIG; } In this case, we didn't modify @pages nor @out_pages, leaving them untouched, then when we cleanup pages, the we can hit NULL pointer dereference again: if (pages) { for (i = 0; i < nr_pages; i++) { WARN_ON(pages[i]->mapping); put_page(pages[i]); } ... } Since pages[i] are all initialized to zero, and btrfs_compress_pages() doesn't change them at all, accessing pages[i]->mapping would lead to NULL pointer dereference. This is not possible for current kernel, as we check inode_need_compress() before doing pages allocation. But if we're going to remove that inode_need_compress() in compress_file_extent(), then it's going to be a problem. [FIX] When btrfs_compress_pages() hits its default case, modify @out_pages to 0 to prevent such problem from happening. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212331 CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: convert kmap to kmap_local_page, simple casesIra Weiny
Use a simple coccinelle script to help convert the most common kmap()/kunmap() patterns to kmap_local_page()/kunmap_local(). Note that some kmaps which were caught by this script needed to be handled by hand because of the strict unmapping order of kunmap_local() so they are not included in this patch. But this script got us started. There's another temp variable added for the final length write to the first page so it does not interfere with cpage_out that is used for mapping other pages. The development of this patch was aided by the follow script: // <smpl> // SPDX-License-Identifier: GPL-2.0-only // Find kmap and replace with kmap_local_page then mark kunmap // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ @ catch_all @ expression e, e2; @@ ( -kmap(e) +kmap_local_page(e) ) ... ( -kunmap(...) +kunmap_local() ) // </smpl> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-03-01Merge branch 'kmap-conversion-for-5.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull kmap conversion updates from David Sterba: "This contains changes regarding kmap API use and eg conversion from kmap_atomic to kmap_local_page. The API belongs to memory management but to save cross-tree dependency headaches we've agreed to take it through the btrfs tree because there are some trivial conversions possible, while the rest will need some time and getting the easy cases out of the way would be convenient. The changes can be grouped: - function exports, new helpers - new VM_BUG_ON for additional verification; it's been discussed if it should be VM_BUG_ON or BUG_ON, the former was chosen due to performance reasons - code replaced by relevant helpers" [ This is an updated version of a request that originally came in during the merge window, but I asked for some updates: https://lore.kernel.org/lkml/cover.1614090658.git.dsterba@suse.com/ which is why this got merge after the merge window closed. - Linus ] * 'kmap-conversion-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: use copy_highpage() instead of 2 kmaps() btrfs: use memcpy_[to|from]_page() and kmap_local_page() mm/highmem: Add VM_BUG_ON() to mem*_page() calls mm/highmem: Introduce memcpy_page(), memmove_page(), and memset_page() mm/highmem: Convert memcpy_[to|from]_page() to kmap_local_page() mm/highmem: Lift memcpy_[to|from]_page to core
2021-02-26btrfs: use memcpy_[to|from]_page() and kmap_local_page()Ira Weiny
There are many places where the pattern kmap/memcpy/kunmap occurs. This pattern was lifted to the core common functions memcpy_[to|from]_page(). Use these new functions to reduce the code, eliminate direct uses of kmap, and leverage the new core functions use of kmap_local_page(). Also, there is 1 place where a kmap/memcpy is followed by an optional memset. Here we leave the kmap open coded to avoid remapping the page but use kmap_local_page() directly. Development of this patch was aided by the coccinelle script: // <smpl> // SPDX-License-Identifier: GPL-2.0-only // Find kmap/memcpy/kunmap pattern and replace with memcpy*page calls // // NOTE: Offsets and other expressions may be more complex than what the script // will automatically generate. Therefore a catchall rule is provided to find // the pattern which then must be evaluated by hand. // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ // Comments: // Options: // // simple memcpy version // @ memcpy_rule1 @ expression page, T, F, B, Off; identifier ptr; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( -memcpy(ptr + Off, F, B); +memcpy_to_page(page, Off, F, B); | -memcpy(ptr, F, B); +memcpy_to_page(page, 0, F, B); | -memcpy(T, ptr + Off, B); +memcpy_from_page(T, page, Off, B); | -memcpy(T, ptr, B); +memcpy_from_page(T, page, 0, B); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memcpy_rule1 @ identifier memcpy_rule1.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // // Some callers kmap without a temp pointer // @ memcpy_rule2 @ expression page, T, Off, F, B; @@ <+... ( -memcpy(kmap(page) + Off, F, B); +memcpy_to_page(page, Off, F, B); | -memcpy(kmap(page), F, B); +memcpy_to_page(page, 0, F, B); | -memcpy(T, kmap(page) + Off, B); +memcpy_from_page(T, page, Off, B); | -memcpy(T, kmap(page), B); +memcpy_from_page(T, page, 0, B); ) ...+> -kunmap(page); // No need for the ptr variable removal // // Catch all // @ memcpy_rule3 @ expression page; expression GenTo, GenFrom, GenSize; identifier ptr; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( // // Some call sites have complex expressions within the memcpy // match a catch all to be evaluated by hand. // -memcpy(GenTo, GenFrom, GenSize); +memcpy_to_pageExtra(page, GenTo, GenFrom, GenSize); +memcpy_from_pageExtra(GenTo, page, GenFrom, GenSize); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memcpy_rule3 @ identifier memcpy_rule3.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // <smpl> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-22btrfs: make check_compressed_csum() to be subpage compatibleQu Wenruo
Currently check_compressed_csum() completely relies on sectorsize == PAGE_SIZE to do checksum verification for compressed extents. To make it subpage compatible, this patch will: - Do extra calculation for the csum range Since we have multiple sectors inside a page, we need to only hash the range we want, not the full page anymore. - Do sector-by-sector hash inside the page With this patch and previous conversion on btrfs_submit_compressed_read(), now we can read subpage compressed extents properly, and do proper csum verification. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-22btrfs: make btrfs_submit_compressed_read() subpage compatibleQu Wenruo
For compressed read, we always submit page read using page size. This doesn't work well with subpage, as for subpage one page can contain several sectors. Such submission will read range out of what we want, and cause problems. Thankfully to make it subpage compatible, we only need to change how the last page of the compressed extent is read. Instead of always adding a full page to the compressed read bio, if we're at the last page, calculate the size using compressed length, so that we only add part of the range into the compressed read bio. Since we are here, also change the PAGE_SIZE used in lookup_extent_mapping() to sectorsize. This modification won't cause any functional change, as lookup_extent_mapping() can handle the case where the search range is larger than found extent range. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: introduce btrfs_subpage for data inodesQu Wenruo
To support subpage sector size, data also need extra info to make sure which sectors in a page are uptodate/dirty/... This patch will make pages for data inodes get btrfs_subpage structure attached, and detached when the page is freed. This patch also slightly changes the timing when set_page_extent_mapped() is called to make sure: - We have page->mapping set page->mapping->host is used to grab btrfs_fs_info, thus we can only call this function after page is mapped to an inode. One call site attaches pages to inode manually, thus we have to modify the timing of set_page_extent_mapped() a bit. - As soon as possible, before other operations Since memory allocation can fail, we have to do extra error handling. Calling set_page_extent_mapped() as soon as possible can simply the error handling for several call sites. The idea is pretty much the same as iomap_page, but with more bitmaps for btrfs specific cases. Currently the plan is to switch iomap if iomap can provide sector aligned write back (only write back dirty sectors, but not the full page, data balance require this feature). So we will stick to btrfs specific bitmap for now. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecsQu Wenruo
Refactor btrfs_lookup_bio_sums() by: - Remove the @file_offset parameter There are two factors making the @file_offset parameter useless: * For csum lookup in csum tree, file offset makes no sense We only need disk_bytenr, which is unrelated to file_offset * page_offset (file offset) of each bvec is not contiguous. Pages can be added to the same bio as long as their on-disk bytenr is contiguous, meaning we could have pages at different file offsets in the same bio. Thus passing file_offset makes no sense any more. The only user of file_offset is for data reloc inode, we will use a new function, search_file_offset_in_bio(), to handle it. - Extract the csum tree lookup into search_csum_tree() The new function will handle the csum search in csum tree. The return value is the same as btrfs_find_ordered_sum(), returning the number of found sectors which have checksum. - Change how we do the main loop The only needed info from bio is: * the on-disk bytenr * the length After extracting the above info, we can do the search without bio at all, which makes the main loop much simpler: for (cur_disk_bytenr = orig_disk_bytenr; cur_disk_bytenr < orig_disk_bytenr + orig_len; cur_disk_bytenr += count * sectorsize) { /* Lookup csum tree */ count = search_csum_tree(fs_info, path, cur_disk_bytenr, search_len, csum_dst); if (!count) { /* Csum hole handling */ } } - Use single variable as the source to calculate all other offsets Instead of all different type of variables, we use only one main variable, cur_disk_bytenr, which represents the current disk bytenr. All involved values can be calculated from that variable, and all those variable will only be visible in the inner loop. The above refactoring makes btrfs_lookup_bio_sums() way more robust than it used to be, especially related to the file offset lookup. Now file_offset lookup is only related to data reloc inode, otherwise we don't need to bother file_offset at all. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09btrfs: drop casts of bio bi_sectorDavid Sterba
Since commit 72deb455b5ec ("block: remove CONFIG_LBDAF") (5.2) the sector_t type is u64 on all arches and configs so we don't need to typecast it. It used to be unsigned long and the result of sector size shifts were not guaranteed to fit in the type. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08btrfs: remove unnecessary local variables for checksum sizeDavid Sterba
Remove local variable that is then used just once and replace it with fs_info::csum_size. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08btrfs: switch cached fs_info::csum_size from u16 to u32David Sterba
The fs_info value is 32bit, switch also the local u16 variables. This leads to a better assembly code generated due to movzwl. This simple change will shave some bytes on x86_64 and release config: text data bss dec hex filename 1090000 17980 14912 1122892 11224c pre/btrfs.ko 1089794 17980 14912 1122686 11217e post/btrfs.ko DELTA: -206 Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>