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path: root/fs/btrfs/ordered-data.h
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2024-03-04btrfs: add forward declarations and headers, part 2David Sterba
Do a cleanup in more headers: - add forward declarations for types referenced by pointers - add includes when types need them This fixes potential compilation problems if the headers are reordered or the missing includes are not provided indirectly. Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: add forward declarations and headers, part 1David Sterba
Do a cleanup in the short headers: - add forward declarations for types referenced by pointers - add includes when types need them This fixes potential compilation problems if the headers are reordered or the missing includes are not provided indirectly. Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: remove unused btrfs_ordered_extent::outstanding_isizeDavid Sterba
The whole isize code was deleted in 5.6 3f1c64ce0438 ("btrfs: delete the ordered isize update code"), except the struct member. This was found by tool https://github.com/jirislaby/clang-struct . Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12btrfs: open code btrfs_ordered_inode_tree in btrfs_inodeDavid Sterba
The structure btrfs_ordered_inode_tree is used only in one place, in btrfs_inode. The structure itself has a 4 byte hole which is wasted space. Move the btrfs_ordered_inode_tree members to btrfs_inode with a common prefix 'ordered_tree_' where the hole can be utilized and shrink inode size. Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12btrfs: add support for inserting raid stripe extentsJohannes Thumshirn
Add support for inserting stripe extents into the raid stripe tree on completion of every write that needs an extra logical-to-physical translation when using RAID. Inserting the stripe extents happens after the data I/O has completed, this is done to a) support zone-append and b) rule out the possibility of a RAID-write-hole. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: add a btrfs_finish_ordered_extent helperChristoph Hellwig
Add a helper to complete an ordered_extent without first doing a lookup. The tracepoint cannot use the ordered_extent class as we also want to print the range. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: remove btrfs_add_ordered_extentChristoph Hellwig
All callers are gone now. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: defer splitting of ordered extents until I/O completionChristoph Hellwig
The btrfs zoned completion code currently needs an ordered_extent and extent_map per bio so that it can account for the non-predictable write location from Zone Append. To archive that it currently splits the ordered_extent and extent_map at I/O submission time, and then records the actual physical address in the ->physical field of the ordered_extent. This patch instead switches to record the "original" physical address that the btrfs allocator assigned in spare space in the btrfs_bio, and then rewrites the logical address in the btrfs_ordered_sum structure at I/O completion time. This allows the ordered extent completion handler to simply walk the list of ordered csums and split the ordered extent as needed. This removes an extra ordered extent and extent_map lookup and manipulation during the I/O submission path, and instead batches it in the I/O completion path where we need to touch these anyway. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: return the new ordered_extent from btrfs_split_ordered_extentChristoph Hellwig
Return the ordered_extent split from the passed in one. This will be needed to be able to store an ordered_extent in the btrfs_bio. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: optimize the logical to physical mapping for zoned writesChristoph Hellwig
The current code to store the final logical to physical mapping for a zone append write in the extent tree is rather inefficient. It first has to split the ordered extent so that there is one ordered extent per bio, so that it can look up the ordered extent on I/O completion in btrfs_record_physical_zoned and store the physical LBA returned by the block driver in the ordered extent. btrfs_rewrite_logical_zoned then has to do a lookup in the chunk tree to see what physical address the logical address for this bio / ordered extent is mapped to, and then rewrite it in the extent tree. To optimize this process, we can store the physical address assigned in the chunk tree to the original logical address and a pointer to btrfs_ordered_sum structure the in the btrfs_bio structure, and then use this information to rewrite the logical address in the btrfs_ordered_sum structure directly at I/O completion time in btrfs_record_physical_zoned. btrfs_rewrite_logical_zoned then simply updates the logical address in the extent tree and the ordered_extent itself. The code in btrfs_rewrite_logical_zoned now runs for all data I/O completions in zoned file systems, which is fine as there is no remapping to do for non-append writes to conventional zones or for relocation, and the overhead for quickly breaking out of the loop is very low. Because zoned file systems now need the ordered_sums structure to record the actual write location returned by zone append, allocate dummy structures without the csum array for them when the I/O doesn't use checksums, and free them when completing the ordered_extent. Note that the btrfs_bio doesn't grow as the new field are places into a union that is so far not used for data writes and has plenty of space left in it. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: rename the bytenr field in struct btrfs_ordered_sum to logicalChristoph Hellwig
btrfs_ordered_sum::bytendr stores a logical address. Make that clear by renaming it to ->logical. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19btrfs: mark the len field in struct btrfs_ordered_sum as unsignedChristoph Hellwig
len can't ever be negative, so mark it as an u32 instead of int. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17btrfs: sink parameter len to btrfs_split_ordered_extentChristoph Hellwig
btrfs_split_ordered_extent is only ever asked to split out the beginning of an ordered_extent (i.e. post == 0). Change it to only take a len to split out, and switch it to allocate the new extent for the beginning, as that helps with callers that want to keep a pointer to the ordered_extent that it is stealing from. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17btrfs: pass flags as unsigned long to btrfs_add_ordered_extentBoris Burkov
The ordered_extent flags are declared as unsigned long, so pass them as such to btrfs_add_ordered_extent. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Boris Burkov <boris@bur.io> [ hch: split from a larger patch ] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17btrfs: add function to create and return an ordered extentBoris Burkov
Currently, btrfs_add_ordered_extent allocates a new ordered extent, adds it to the rb_tree, but doesn't return a referenced pointer to the caller. There are cases where it is useful for the creator of a new ordered_extent to hang on to such a pointer, so add a new function btrfs_alloc_ordered_extent which is the same as btrfs_add_ordered_extent, except it takes an additional reference count and returns a pointer to the ordered_extent. Implement btrfs_add_ordered_extent as btrfs_alloc_ordered_extent followed by dropping the new reference and handling the IS_ERR case. The type of flags in btrfs_alloc_ordered_extent and btrfs_add_ordered_extent is changed from unsigned int to unsigned long so it's unified with the other ordered extent functions. Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15btrfs: don't rely on unchanging ->bi_bdev for zone append remapsChristoph Hellwig
btrfs_record_physical_zoned relies on a bio->bi_bdev samples in the bio_end_io handler to find the reverse map for remapping the zone append write, but stacked block device drivers can and usually do change bi_bdev when sending on the bio to a lower device. This can happen e.g. with the nvme-multipath driver when a NVMe SSD sets the shared namespace bit. But there is no real need for the bdev in btrfs_record_physical_zoned, as it is only passed to btrfs_rmap_block, which uses it to pick the mapping to report if there are multiple reverse mappings. As zone writes can only do simple non-mirror writes right now, and anything more complex will use the stripe tree there is no chance of the multiple mappings case actually happening. Instead open code the subset of btrfs_rmap_block in btrfs_record_physical_zoned, which also removes a memory allocation and remove the bdev field in the ordered extent. Fixes: d8e3fb106f39 ("btrfs: zoned: use ZONE_APPEND write for zoned mode") Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-13btrfs: remove the wait argument to btrfs_start_ordered_extentChristoph Hellwig
Given that wait is always set to 1, so remove the argument. Last use of wait with 0 was in 0c304304feab ("Btrfs: remove csum_bytes_left"). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05btrfs: use cached_state for btrfs_check_nocow_lockJosef Bacik
Now that try_lock_extent() takes a cached_state, plumb the cached_state through btrfs_try_lock_ordered_range() and then use a cached_state in btrfs_check_nocow_lock everywhere to avoid extra tree searches on the extent_io_tree. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-29btrfs: add btrfs_try_lock_ordered_rangeJosef Bacik
For IOCB_NOWAIT we're going to want to use try lock on the extent lock, and simply bail if there's an ordered extent in the range because the only choice there is to wait for the ordered extent to complete. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Stefan Roesch <shr@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26btrfs: move btrfs_ordered_sum_size into file-item.cJosef Bacik
This is defined in ordered-data.h, but is only used in file-item.c. Move this to file-item.c as it doesn't need to be global. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25btrfs: remove the finish_func argument to btrfs_mark_ordered_io_finishedChristoph Hellwig
finish_func is always set to finish_ordered_fn, so remove it and also the now pointless and somewhat confusingly named __endio_write_update_ordered wrapper. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14btrfs: add BTRFS_IOC_ENCODED_WRITEOmar Sandoval
The implementation resembles direct I/O: we have to flush any ordered extents, invalidate the page cache, and do the io tree/delalloc/extent map/ordered extent dance. From there, we can reuse the compression code with a minor modification to distinguish the write from writeback. This also creates inline extents when possible. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14btrfs: add ram_bytes and offset to btrfs_ordered_extentOmar Sandoval
Currently, we only create ordered extents when ram_bytes == num_bytes and offset == 0. However, BTRFS_IOC_ENCODED_WRITE writes may create extents which only refer to a subset of the full unencoded extent, so we need to plumb these fields through the ordered extent infrastructure and pass them down to insert_reserved_file_extent(). Since we're changing the btrfs_add_ordered_extent* signature, let's get rid of the trivial wrappers and add a kernel-doc. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pendingDavid Sterba
In commit e65f152e4348 ("btrfs: refactor how we finish ordered extent io for endio functions") there was last caller not using 1 for the uptodate parameter. Now there's only one, passing 1, so we can remove it and simplify the code. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-07-22btrfs: store a block_device in struct btrfs_ordered_extentChristoph Hellwig
Store the block device instead of the gendisk in the btrfs_ordered_extent structure instead of acquiring a reference to it later. Note: this is from series removing bdgrab/bdput, btrfs is one of the last users. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: introduce btrfs_lookup_first_ordered_range()Qu Wenruo
Although we already have btrfs_lookup_first_ordered_extent() and btrfs_lookup_ordered_extent(), they all have their own limitations: - btrfs_lookup_ordered_extent() can't do extra range check It's only designed to lookup any ordered extent before certain bytenr. - btrfs_lookup_first_ordered_extent() may not return the first ordered extent in the range It doesn't ensure the first ordered extent is returned. The existing callers are only interested in exhausting all ordered extents in a range, the order is not important. For incoming btrfs_invalidatepage() refactoring, we need a way to properly iterate all ordered extents in their bytenr order of a range. So this patch will introduce a new function, btrfs_lookup_first_ordered_range(), to do ordered extent with bytenr order awareness and extra range check. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: refactor how we finish ordered extent io for endio functionsQu Wenruo
Btrfs has two endio functions to mark certain io range finished for ordered extents: - __endio_write_update_ordered() This is for direct IO - btrfs_writepage_endio_finish_ordered() This for buffered IO. However they go different routines to handle ordered extent io: - Whether to iterate through all ordered extents __endio_write_update_ordered() will but btrfs_writepage_endio_finish_ordered() will not. In fact, iterating through all ordered extents will benefit later subpage support, while for current PAGE_SIZE == sectorsize requirement this behavior makes no difference. - Whether to update page Private2 flag __endio_write_update_ordered() will not update page Private2 flag as for iomap direct IO, the page can not be even mapped. While btrfs_writepage_endio_finish_ordered() will clear Private2 to prevent double accounting against btrfs_invalidatepage(). Those differences are pretty subtle, and the ordered extent iterations code in callers makes code much harder to read. So this patch will introduce a new function, btrfs_mark_ordered_io_finished(), to do the heavy lifting: - Iterate through all ordered extents in the range - Do the ordered extent accounting - Queue the work for finished ordered extent This function has two new feature: - Proper underflow detection and recovery The old underflow detection will only detect the problem, then continue. No proper info like root/inode/ordered extent info, nor noisy enough to be caught by fstests. Furthermore when underflow happens, the ordered extent will never finish. New error detection will reset the bytes_left to 0, do proper kernel warning, and output extra info including root, ino, ordered extent range, the underflow value. - Prevent double accounting based on Private2 flag Now if we find a range without Private2 flag, we will skip to next range. As that means someone else has already finished the accounting of ordered extent. This makes no difference for current code, but will be a critical part for incoming subpage support, as we can call btrfs_mark_ordered_io_finished() for multiple sectors if they are beyond inode size. Thus such double accounting prevention is a key feature for subpage. Now both endio functions only need to call that new function. And since the only caller of btrfs_dec_test_first_ordered_pending() is removed, also remove btrfs_dec_test_first_ordered_pending() completely. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: fix comment for btrfs ordered extent flag bitsQu Wenruo
There is small error in comment about BTRFS_ORDERED_* flags, added in commit 3c198fe06449 ("btrfs: rework the order of btrfs_ordered_extent::flags") but the fixup did not get merged in time. The 4 types are for ordered extent itself, not for direct io. Only 3 types support direct io, REGULAR/NOCOW/PREALLOC. Fix the comment to reflect that. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-09btrfs: zoned: use ZONE_APPEND write for zoned modeNaohiro Aota
Enable zone append writing for zoned mode. When using zone append, a bio is issued to the start of a target zone and the device decides to place it inside the zone. Upon completion the device reports the actual written position back to the host. Three parts are necessary to enable zone append mode. First, modify the bio to use REQ_OP_ZONE_APPEND in btrfs_submit_bio_hook() and adjust the bi_sector to point the beginning of the zone. Second, record the returned physical address (and disk/partno) to the ordered extent in end_bio_extent_writepage() after the bio has been completed. We cannot resolve the physical address to the logical address because we can neither take locks nor allocate a buffer in this end_bio context. So, we need to record the physical address to resolve it later in btrfs_finish_ordered_io(). And finally, rewrite the logical addresses of the extent mapping and checksum data according to the physical address using btrfs_rmap_block. If the returned address matches the originally allocated address, we can skip this rewriting process. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-09btrfs: zoned: split ordered extent when bio is sentNaohiro Aota
For a zone append write, the device decides the location the data is being written to. Therefore we cannot ensure that two bios are written consecutively on the device. In order to ensure that an ordered extent maps to a contiguous region on disk, we need to maintain a "one bio == one ordered extent" rule. Implement splitting of an ordered extent and extent map on bio submission to adhere to the rule. extract_ordered_extent() hooks into btrfs_submit_data_bio() and splits the corresponding ordered extent so that the ordered extent's region fits into one bio and the corresponding device limits. Several sanity checks need to be done in extract_ordered_extent() e.g. - We cannot split once end_bio'd ordered extent because we cannot divide ordered->bytes_left for the split ones - We do not expect a compressed ordered extent - We should not have checksum list because we omit the list splitting. Since the function is called before btrfs_wq_submit_bio() or btrfs_csum_one_bio(), this should be always ensured. We also need to split an extent map by creating a new one. If not, unpin_extent_cache() complains about the difference between the start of the extent map and the file's logical offset. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08btrfs: rework the order of btrfs_ordered_extent::flagsQu Wenruo
[BUG] There is a long existing bug in the last parameter of btrfs_add_ordered_extent(), in commit 771ed689d2cd ("Btrfs: Optimize compressed writeback and reads") back to 2008. In that ancient commit btrfs_add_ordered_extent() expects the @type parameter to be one of the following: - BTRFS_ORDERED_REGULAR - BTRFS_ORDERED_NOCOW - BTRFS_ORDERED_PREALLOC - BTRFS_ORDERED_COMPRESSED But we pass 0 in cow_file_range(), which means BTRFS_ORDERED_IO_DONE. Ironically extra check in __btrfs_add_ordered_extent() won't set the bit if we see (type == IO_DONE || type == IO_COMPLETE), and avoid any obvious bug. But this still leads to regular COW ordered extent having no bit to indicate its type in various trace events, rendering REGULAR bit useless. [FIX] Change the following aspects to avoid such problem: - Reorder btrfs_ordered_extent::flags Now the type bits go first (REGULAR/NOCOW/PREALLCO/COMPRESSED), then DIRECT bit, finally extra status bits like IO_DONE/COMPLETE/IOERR. - Add extra ASSERT() for btrfs_add_ordered_extent_*() - Remove @type parameter for btrfs_add_ordered_extent_compress() As the only valid @type here is BTRFS_ORDERED_COMPRESSED. - Remove the unnecessary special check for IO_DONE/COMPLETE in __btrfs_add_ordered_extent() This is just to make the code work, with extra ASSERT(), there are limited values can be passed in. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.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: refactor btrfs_dec_test_* functions for ordered extentsQu Wenruo
The refactoring involves the following modifications: - Return bool instead of int - Parameter update for @cached of btrfs_dec_test_first_ordered_pending() For btrfs_dec_test_first_ordered_pending(), @cached is only used to return the finished ordered extent. Rename it to @finished_ret. - Comment updates * Change one stale comment Which still refers to btrfs_dec_test_ordered_pending(), but the context is calling btrfs_dec_test_first_ordered_pending(). * Follow the common comment style for both functions Add more detailed descriptions for parameters and the return value * Move the reason why test_and_set_bit() is used into the call sites - Change how the return value is calculated The most anti-human part of the return value is: if (...) ret = 1; ... return ret == 0; This means, when we set ret to 1, the function returns 0. Change the local variable name to @finished, and directly return the value of it. 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: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sumsQu Wenruo
The function btrfs_lookup_bio_sums() is only called for read bios. While btrfs_find_ordered_sum() is to search ordered extent sums, which is only for write path. This means to read a page we either: - Submit read bio if it's not uptodate This means we only need to search csum tree for checksums. - The page is already uptodate It can be marked uptodate for previous read, or being marked dirty. As we always mark page uptodate for dirty page. In that case, we don't need to submit read bio at all, thus no need to search any checksums. Remove the btrfs_find_ordered_sum() call in btrfs_lookup_bio_sums(). And since btrfs_lookup_bio_sums() is the only caller for btrfs_find_ordered_sum(), also remove the implementation. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.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>
2020-12-08btrfs: use cached value of fs_info::csum_size everywhereDavid Sterba
btrfs_get_16 shows up in the system performance profiles (helper to read 16bit values from on-disk structures). This is partially because of the checksum size that's frequently read along with data reads/writes, other u16 uses are from item size or directory entries. Replace all calls to btrfs_super_csum_size by the cached value from fs_info. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: remove inode argument from btrfs_start_ordered_extentNikolay Borisov
The passed in ordered_extent struct is always well-formed and contains the inode making the explicit argument redundant. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: switch btrfs_remove_ordered_extent to btrfs_inodeNikolay Borisov
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: make btrfs_find_ordered_sum take btrfs_inodeNikolay Borisov
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: make btrfs_dec_test_ordered_pending take btrfs_inodeNikolay Borisov
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: make btrfs_lookup_first_ordered_extent take btrfs_inodeNikolay Borisov
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07btrfs: make fast fsyncs wait only for writebackFilipe Manana
Currently regardless of a full or a fast fsync we always wait for ordered extents to complete, and then start logging the inode after that. However for fast fsyncs we can just wait for the writeback to complete, we don't need to wait for the ordered extents to complete since we use the list of modified extents maps to figure out which extents we must log and we can get their checksums directly from the ordered extents that are still in flight, otherwise look them up from the checksums tree. Until commit b5e6c3e170b770 ("btrfs: always wait on ordered extents at fsync time"), for fast fsyncs, we used to start logging without even waiting for the writeback to complete first, we would wait for it to complete after logging, while holding a transaction open, which lead to performance issues when using cgroups and probably for other cases too, as wait for IO while holding a transaction handle should be avoided as much as possible. After that, for fast fsyncs, we started to wait for ordered extents to complete before starting to log, which adds some latency to fsyncs and we even got at least one report about a performance drop which bisected to that particular change: https://lore.kernel.org/linux-btrfs/20181109215148.GF23260@techsingularity.net/ This change makes fast fsyncs only wait for writeback to finish before starting to log the inode, instead of waiting for both the writeback to finish and for the ordered extents to complete. This brings back part of the logic we had that extracts checksums from in flight ordered extents, which are not yet in the checksums tree, and making sure transaction commits wait for the completion of ordered extents previously logged (by far most of the time they have already completed by the time a transaction commit starts, resulting in no wait at all), to avoid any data loss if an ordered extent completes after the transaction used to log an inode is committed, followed by a power failure. When there are no other tasks accessing the checksums and the subvolume btrees, the ordered extent completion is pretty fast, typically taking 100 to 200 microseconds only in my observations. However when there are other tasks accessing these btrees, ordered extent completion can take a lot more time due to lock contention on nodes and leaves of these btrees. I've seen cases over 2 milliseconds, which starts to be significant. In particular when we do have concurrent fsyncs against different files there is a lot of contention on the checksums btree, since we have many tasks writing the checksums into the btree and other tasks that already started the logging phase are doing lookups for checksums in the btree. This change also turns all ranged fsyncs into full ranged fsyncs, which is something we already did when not using the NO_HOLES features or when doing a full fsync. This is to guarantee we never miss checksums due to writeback having been triggered only for a part of an extent, and we end up logging the full extent but only checksums for the written range, which results in missing checksums after log replay. Allowing ranged fsyncs to operate again only in the original range, when using the NO_HOLES feature and doing a fast fsync is doable but requires some non trivial changes to the writeback path, which can always be worked on later if needed, but I don't think they are a very common use case. Several tests were performed using fio for different numbers of concurrent jobs, each writing and fsyncing its own file, for both sequential and random file writes. The tests were run on bare metal, no virtualization, on a box with 12 cores (Intel i7-8700), 64Gb of RAM and a NVMe device, with a kernel configuration that is the default of typical distributions (debian in this case), without debug options enabled (kasan, kmemleak, slub debug, debug of page allocations, lock debugging, etc). The following script that calls fio was used: $ cat test-fsync.sh #!/bin/bash DEV=/dev/nvme0n1 MNT=/mnt/btrfs MOUNT_OPTIONS="-o ssd -o space_cache=v2" MKFS_OPTIONS="-d single -m single" if [ $# -ne 5 ]; then echo "Use $0 NUM_JOBS FILE_SIZE FSYNC_FREQ BLOCK_SIZE [write|randwrite]" exit 1 fi NUM_JOBS=$1 FILE_SIZE=$2 FSYNC_FREQ=$3 BLOCK_SIZE=$4 WRITE_MODE=$5 if [ "$WRITE_MODE" != "write" ] && [ "$WRITE_MODE" != "randwrite" ]; then echo "Invalid WRITE_MODE, must be 'write' or 'randwrite'" exit 1 fi cat <<EOF > /tmp/fio-job.ini [writers] rw=$WRITE_MODE fsync=$FSYNC_FREQ fallocate=none group_reporting=1 direct=0 bs=$BLOCK_SIZE ioengine=sync size=$FILE_SIZE directory=$MNT numjobs=$NUM_JOBS EOF echo "performance" | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor echo echo "Using config:" echo cat /tmp/fio-job.ini echo umount $MNT &> /dev/null mkfs.btrfs -f $MKFS_OPTIONS $DEV mount $MOUNT_OPTIONS $DEV $MNT fio /tmp/fio-job.ini umount $MNT The results were the following: ************************* *** sequential writes *** ************************* ==== 1 job, 8GiB file, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=36.6MiB/s (38.4MB/s), 36.6MiB/s-36.6MiB/s (38.4MB/s-38.4MB/s), io=8192MiB (8590MB), run=223689-223689msec After patch: WRITE: bw=40.2MiB/s (42.1MB/s), 40.2MiB/s-40.2MiB/s (42.1MB/s-42.1MB/s), io=8192MiB (8590MB), run=203980-203980msec (+9.8%, -8.8% runtime) ==== 2 jobs, 4GiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=35.8MiB/s (37.5MB/s), 35.8MiB/s-35.8MiB/s (37.5MB/s-37.5MB/s), io=8192MiB (8590MB), run=228950-228950msec After patch: WRITE: bw=43.5MiB/s (45.6MB/s), 43.5MiB/s-43.5MiB/s (45.6MB/s-45.6MB/s), io=8192MiB (8590MB), run=188272-188272msec (+21.5% throughput, -17.8% runtime) ==== 4 jobs, 2GiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=50.1MiB/s (52.6MB/s), 50.1MiB/s-50.1MiB/s (52.6MB/s-52.6MB/s), io=8192MiB (8590MB), run=163446-163446msec After patch: WRITE: bw=64.5MiB/s (67.6MB/s), 64.5MiB/s-64.5MiB/s (67.6MB/s-67.6MB/s), io=8192MiB (8590MB), run=126987-126987msec (+28.7% throughput, -22.3% runtime) ==== 8 jobs, 1GiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=64.0MiB/s (68.1MB/s), 64.0MiB/s-64.0MiB/s (68.1MB/s-68.1MB/s), io=8192MiB (8590MB), run=126075-126075msec After patch: WRITE: bw=86.8MiB/s (91.0MB/s), 86.8MiB/s-86.8MiB/s (91.0MB/s-91.0MB/s), io=8192MiB (8590MB), run=94358-94358msec (+35.6% throughput, -25.2% runtime) ==== 16 jobs, 512MiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=79.8MiB/s (83.6MB/s), 79.8MiB/s-79.8MiB/s (83.6MB/s-83.6MB/s), io=8192MiB (8590MB), run=102694-102694msec After patch: WRITE: bw=107MiB/s (112MB/s), 107MiB/s-107MiB/s (112MB/s-112MB/s), io=8192MiB (8590MB), run=76446-76446msec (+34.1% throughput, -25.6% runtime) ==== 32 jobs, 512MiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=93.2MiB/s (97.7MB/s), 93.2MiB/s-93.2MiB/s (97.7MB/s-97.7MB/s), io=16.0GiB (17.2GB), run=175836-175836msec After patch: WRITE: bw=111MiB/s (117MB/s), 111MiB/s-111MiB/s (117MB/s-117MB/s), io=16.0GiB (17.2GB), run=147001-147001msec (+19.1% throughput, -16.4% runtime) ==== 64 jobs, 512MiB files, fsync frequency 1, block size 64KiB ==== Before patch: WRITE: bw=108MiB/s (114MB/s), 108MiB/s-108MiB/s (114MB/s-114MB/s), io=32.0GiB (34.4GB), run=302656-302656msec After patch: WRITE: bw=133MiB/s (140MB/s), 133MiB/s-133MiB/s (140MB/s-140MB/s), io=32.0GiB (34.4GB), run=246003-246003msec (+23.1% throughput, -18.7% runtime) ************************ *** random writes *** ************************ ==== 1 job, 8GiB file, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=11.5MiB/s (12.0MB/s), 11.5MiB/s-11.5MiB/s (12.0MB/s-12.0MB/s), io=8192MiB (8590MB), run=714281-714281msec After patch: WRITE: bw=11.6MiB/s (12.2MB/s), 11.6MiB/s-11.6MiB/s (12.2MB/s-12.2MB/s), io=8192MiB (8590MB), run=705959-705959msec (+0.9% throughput, -1.7% runtime) ==== 2 jobs, 4GiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=12.8MiB/s (13.5MB/s), 12.8MiB/s-12.8MiB/s (13.5MB/s-13.5MB/s), io=8192MiB (8590MB), run=638101-638101msec After patch: WRITE: bw=13.1MiB/s (13.7MB/s), 13.1MiB/s-13.1MiB/s (13.7MB/s-13.7MB/s), io=8192MiB (8590MB), run=625374-625374msec (+2.3% throughput, -2.0% runtime) ==== 4 jobs, 2GiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=15.4MiB/s (16.2MB/s), 15.4MiB/s-15.4MiB/s (16.2MB/s-16.2MB/s), io=8192MiB (8590MB), run=531146-531146msec After patch: WRITE: bw=17.8MiB/s (18.7MB/s), 17.8MiB/s-17.8MiB/s (18.7MB/s-18.7MB/s), io=8192MiB (8590MB), run=460431-460431msec (+15.6% throughput, -13.3% runtime) ==== 8 jobs, 1GiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=19.9MiB/s (20.8MB/s), 19.9MiB/s-19.9MiB/s (20.8MB/s-20.8MB/s), io=8192MiB (8590MB), run=412664-412664msec After patch: WRITE: bw=22.2MiB/s (23.3MB/s), 22.2MiB/s-22.2MiB/s (23.3MB/s-23.3MB/s), io=8192MiB (8590MB), run=368589-368589msec (+11.6% throughput, -10.7% runtime) ==== 16 jobs, 512MiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=29.3MiB/s (30.7MB/s), 29.3MiB/s-29.3MiB/s (30.7MB/s-30.7MB/s), io=8192MiB (8590MB), run=279924-279924msec After patch: WRITE: bw=30.4MiB/s (31.9MB/s), 30.4MiB/s-30.4MiB/s (31.9MB/s-31.9MB/s), io=8192MiB (8590MB), run=269258-269258msec (+3.8% throughput, -3.8% runtime) ==== 32 jobs, 512MiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=36.9MiB/s (38.7MB/s), 36.9MiB/s-36.9MiB/s (38.7MB/s-38.7MB/s), io=16.0GiB (17.2GB), run=443581-443581msec After patch: WRITE: bw=41.6MiB/s (43.6MB/s), 41.6MiB/s-41.6MiB/s (43.6MB/s-43.6MB/s), io=16.0GiB (17.2GB), run=394114-394114msec (+12.7% throughput, -11.2% runtime) ==== 64 jobs, 512MiB files, fsync frequency 16, block size 4KiB ==== Before patch: WRITE: bw=45.9MiB/s (48.1MB/s), 45.9MiB/s-45.9MiB/s (48.1MB/s-48.1MB/s), io=32.0GiB (34.4GB), run=714614-714614msec After patch: WRITE: bw=48.8MiB/s (51.1MB/s), 48.8MiB/s-48.8MiB/s (51.1MB/s-51.1MB/s), io=32.0GiB (34.4GB), run=672087-672087msec (+6.3% throughput, -6.0% runtime) Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: make btrfs_add_ordered_extent_dio take btrfs_inodeNikolay Borisov
Simply forwards its argument so let's get rid of one extra BTRFS_I by taking btrfs_inode directly. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: make btrfs_dec_test_first_ordered_pending take btrfs_inodeNikolay Borisov
It doesn't really need vfs_inode but btrfs_inode. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: make btrfs_add_ordered_extent_compress take btrfs_inodeNikolay Borisov
It simpy forwards its inode argument to __btrfs_add_ordered_extent which already takes btrfs_inode. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: make btrfs_add_ordered_extent take btrfs_inodeNikolay Borisov
Preparation to converting its callers to taking btrfs_inode. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: make btrfs_lookup_ordered_extent take btrfs_inodeNikolay Borisov
It doesn't use the generic vfs inode for anything use btrfs_inode directly. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: remove no longer used trans_list member of struct btrfs_ordered_extentFilipe Manana
The 'trans_list' member of an ordered extent was used to keep track of the ordered extents for which a transaction commit had to wait. These were ordered extents that were started and logged by an fsync. However we don't do that anymore and before we stopped doing it we changed the approach to wait for the ordered extents in commit 161c3549b45aee ("Btrfs: change how we wait for pending ordered extents"), which stopped using that list and therefore the 'trans_list' member is not used anymore since that commit. So just remove it since it's doing nothing and making each ordered extent structure waste memory (2 pointers). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: remove no longer used log_list member of struct btrfs_ordered_extentFilipe Manana
The 'log_list' member of an ordered extent was used keep track of which ordered extents we needed to wait after logging metadata, but is not used anymore since commit 5636cf7d6dc86f ("btrfs: remove the logged extents infrastructure"), as we now always wait on ordered extent completion before logging metadata. So just remove it since it's doing nothing and making each ordered extent structure waste more memory (2 pointers). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27btrfs: change timing for qgroup reserved space for ordered extents to fix ↵Qu Wenruo
reserved space leak [BUG] The following simple workload from fsstress can lead to qgroup reserved data space leak: 0/0: creat f0 x:0 0 0 0/0: creat add id=0,parent=-1 0/1: write f0[259 1 0 0 0 0] [600030,27288] 0 0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat() 0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0 This would cause btrfs qgroup to leak 20480 bytes for data reserved space. If btrfs qgroup limit is enabled, such leak can lead to unexpected early EDQUOT and unusable space. [CAUSE] When doing direct IO, kernel will try to writeback existing buffered page cache, then invalidate them: generic_file_direct_write() |- filemap_write_and_wait_range(); |- invalidate_inode_pages2_range(); However for btrfs, the bi_end_io hook doesn't finish all its heavy work right after bio ends. In fact, it delays its work further: submit_extent_page(end_io_func=end_bio_extent_writepage); end_bio_extent_writepage() |- btrfs_writepage_endio_finish_ordered() |- btrfs_init_work(finish_ordered_fn); <<< Work queue execution >>> finish_ordered_fn() |- btrfs_finish_ordered_io(); |- Clear qgroup bits This means, when filemap_write_and_wait_range() returns, btrfs_finish_ordered_io() is not guaranteed to be executed, thus the qgroup bits for related range are not cleared. Now into how the leak happens, this will only focus on the overlapping part of buffered and direct IO part. 1. After buffered write The inode had the following range with QGROUP_RESERVED bit: 596 616K |///////////////| Qgroup reserved data space: 20K 2. Writeback part for range [596K, 616K) Write back finished, but btrfs_finish_ordered_io() not get called yet. So we still have: 596K 616K |///////////////| Qgroup reserved data space: 20K 3. Pages for range [596K, 616K) get released This will clear all qgroup bits, but don't update the reserved data space. So we have: 596K 616K | | Qgroup reserved data space: 20K That number doesn't match the qgroup bit range anymore. 4. Dio prepare space for range [596K, 700K) Qgroup reserved data space for that range, we got: 596K 616K 700K |///////////////|///////////////////////| Qgroup reserved data space: 20K + 104K = 124K 5. btrfs_finish_ordered_range() gets executed for range [596K, 616K) Qgroup free reserved space for that range, we got: 596K 616K 700K | |///////////////////////| We need to free that range of reserved space. Qgroup reserved data space: 124K - 20K = 104K 6. btrfs_finish_ordered_range() gets executed for range [596K, 700K) However qgroup bit for range [596K, 616K) is already cleared in previous step, so we only free 84K for qgroup reserved space. 596K 616K 700K | | | We need to free that range of reserved space. Qgroup reserved data space: 104K - 84K = 20K Now there is no way to release that 20K unless disabling qgroup or unmounting the fs. [FIX] This patch will change the timing of btrfs_qgroup_release/free_data() call. Here it uses buffered COW write as an example. The new timing | The old timing ----------------------------------------+--------------------------------------- btrfs_buffered_write() | btrfs_buffered_write() |- btrfs_qgroup_reserve_data() | |- btrfs_qgroup_reserve_data() | btrfs_run_delalloc_range() | btrfs_run_delalloc_range() |- btrfs_add_ordered_extent() | |- btrfs_qgroup_release_data() | The reserved is passed into | btrfs_ordered_extent structure | | btrfs_finish_ordered_io() | btrfs_finish_ordered_io() |- The reserved space is passed to | |- btrfs_qgroup_release_data() btrfs_qgroup_record | The resereved space is passed | to btrfs_qgroup_recrod | btrfs_qgroup_account_extents() | btrfs_qgroup_account_extents() |- btrfs_qgroup_free_refroot() | |- btrfs_qgroup_free_refroot() The point of such change is to ensure, when ordered extents are submitted, the qgroup reserved space is already released, to keep the timing aligned with file_write_and_wait_range(). So that qgroup data reserved space is all bound to btrfs_ordered_extent and solve the timing mismatch. Fixes: f695fdcef83a ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space") Suggested-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
generated by cgit (git 2.34.1) at 2024-06-11 11:00:53 +0000