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path: root/fs/btrfs/extent_io.c
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2021-10-26btrfs: rename btrfs_bio to btrfs_io_contextQu Wenruo
The structure btrfs_bio is used by two different sites: - bio->bi_private for mirror based profiles For those profiles (SINGLE/DUP/RAID1*/RAID10), this structures records how many mirrors are still pending, and save the original endio function of the bio. - RAID56 code In that case, RAID56 only utilize the stripes info, and no long uses that to trace the pending mirrors. So btrfs_bio is not always bind to a bio, and contains more info for IO context, thus renaming it will make the naming less confusing. 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: zoned: only allow one process to add pages to a relocation inodeJohannes Thumshirn
Don't allow more than one process to add pages to a relocation inode on a zoned filesystem, otherwise we cannot guarantee the sequential write rule once we're filling preallocated extents on a zoned filesystem. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: unexport repair_io_failure()Qu Wenruo
Function repair_io_failure() is no longer used out of extent_io.c since commit 8b9b6f255485 ("btrfs: scrub: cleanup the remaining nodatasum fixup code"), which removes the last external caller. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: convert latest_bdev type to btrfs_device and renameAnand Jain
In preparation to fix a bug in btrfs_show_devname(). Convert fs_devices::latest_bdev type from struct block_device to struct btrfs_device and, rename the member to fs_devices::latest_dev. So that btrfs_show_devname() can use fs_devices::latest_dev::name. Tested-by: Su Yue <l@damenly.su> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: zoned: finish fully written block groupNaohiro Aota
If we have written to the zone capacity, the device automatically deactivates the zone. Sync up block group side (the active BG list and zone_is_active flag) with it. We need to do it both on data BGs and metadata BGs. On data side, we add a hook to btrfs_finish_ordered_io(). On metadata side, we use end_extent_buffer_writeback(). To reduce excess lookup of a block group, we mark the last extent buffer in a block group with EXTENT_BUFFER_ZONE_FINISH flag. This cannot be done for data (ordered_extent), because the address may change due to REQ_OP_ZONE_APPEND. Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26btrfs: subpage: pack all subpage bitmaps into a larger bitmapQu Wenruo
Currently we use u16 bitmap to make 4k sectorsize work for 64K page size. But this u16 bitmap is not large enough to contain larger page size like 128K, nor is space efficient for 16K page size. To handle both cases, here we pack all subpage bitmaps into a larger bitmap, now btrfs_subpage::bitmaps[] will be the ultimate bitmap for subpage usage. Each sub-bitmap will has its start bit number recorded in btrfs_subpage_info::*_start, and its bitmap length will be recorded in btrfs_subpage_info::bitmap_nr_bits. All subpage bitmap operations will be converted from using direct u16 operations to bitmap operations, with above *_start calculated. For 64K page size with 4K sectorsize, this should not cause much difference. While for 16K page size, we will only need 1 unsigned long (u32) to store all the bitmaps, which saves quite some space. Furthermore, this allows us to support larger page size like 128K and 258K. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-25btrfs: subpage: make btrfs_alloc_subpage() return btrfs_subpage directlyQu Wenruo
The existing calling convention of btrfs_alloc_subpage() is pretty awful. Change it to a more common pattern by returning struct btrfs_subpage directly and let the caller to determine if the call succeeded. Reviewed-by: Nikolay Borisov <nborisov@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>
2021-10-25btrfs: subpage: only call btrfs_alloc_subpage() when sectorsize is smaller ↵Qu Wenruo
than PAGE_SIZE There are two call sites of btrfs_alloc_subpage(): - btrfs_attach_subpage() We have ensured sectorsize is smaller than PAGE_SIZE - alloc_extent_buffer() We call btrfs_alloc_subpage() unconditionally. The alloc_extent_buffer() forces us to check the sectorsize size against page size inside btrfs_alloc_subpage(). Since the function name, btrfs_alloc_subpage(), already indicates it should only get called for subpage cases, do the check in alloc_extent_buffer() and add an ASSERT() in btrfs_alloc_subpage(). Reviewed-by: Nikolay Borisov <nborisov@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>
2021-08-23btrfs: zoned: fix ordered extent boundary calculationNaohiro Aota
btrfs_lookup_ordered_extent() is supposed to query the offset in a file instead of the logical address. Pass the file offset from submit_extent_page() to calc_bio_boundaries(). Also, calc_bio_boundaries() relies on the bio's operation flag, so move the call site after setting it. Fixes: 390ed29b817e ("btrfs: refactor submit_extent_page() to make bio and its flag tracing easier") Reviewed-by: Qu Wenruo <wqu@suse.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>
2021-08-23btrfs: initial fsverity supportBoris Burkov
Add support for fsverity in btrfs. To support the generic interface in fs/verity, we add two new item types in the fs tree for inodes with verity enabled. One stores the per-file verity descriptor and btrfs verity item and the other stores the Merkle tree data itself. Verity checking is done in end_page_read just before a page is marked uptodate. This naturally handles a variety of edge cases like holes, preallocated extents, and inline extents. Some care needs to be taken to not try to verity pages past the end of the file, which are accessed by the generic buffered file reading code under some circumstances like reading to the end of the last page and trying to read again. Direct IO on a verity file falls back to buffered reads. Verity relies on PageChecked for the Merkle tree data itself to avoid re-walking up shared paths in the tree. For this reason, we need to cache the Merkle tree data. Since the file is immutable after verity is turned on, we can cache it at an index past EOF. Use the new inode ro_flags to store verity on the inode item, so that we can enable verity on a file, then rollback to an older kernel and still mount the file system and read the file. Since we can't safely write the file anymore without ruining the invariants of the Merkle tree, we mark a ro_compat flag on the file system when a file has verity enabled. Acked-by: Eric Biggers <ebiggers@google.com> Co-developed-by: Chris Mason <clm@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: remove the dead comment in writepage_delalloc()Qu Wenruo
When btrfs_run_delalloc_range() failed, we will error out. But there is a strange comment mentioning that btrfs_run_delalloc_range() could have returned value >0 to indicate the IO has already started. Commit 40f765805f08 ("Btrfs: split up __extent_writepage to lower stack usage") introduced the comment, but unfortunately at that time, we were already using @page_started to indicate that case, and still return 0. Furthermore, even if that comment was right (which is not), we would return -EIO if the IO had already started. By all means the comment is incorrect, just remove the comment along with the dead check. Just to be extra safe, add an ASSERT() in btrfs_run_delalloc_range() to make sure we either return 0 or error, no positive return value. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: fix argument type of btrfs_bio_clone_partial()Chaitanya Kulkarni
The offset and can never be negative use unsigned int instead of int type for them. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@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>
2021-08-23btrfs: unify regular and subpage error paths in __extent_writepage()Qu Wenruo
[BUG] When running btrfs/160 in a loop for subpage with experimental compression support, it has a high chance to crash (~20%): BTRFS critical (device dm-7): panic in __btrfs_add_ordered_extent:238: inconsistency in ordered tree at offset 0 (errno=-17 Object already exists) ------------[ cut here ]------------ kernel BUG at fs/btrfs/ordered-data.c:238! Internal error: Oops - BUG: 0 [#1] SMP pc : __btrfs_add_ordered_extent+0x550/0x670 [btrfs] lr : __btrfs_add_ordered_extent+0x550/0x670 [btrfs] Call trace: __btrfs_add_ordered_extent+0x550/0x670 [btrfs] btrfs_add_ordered_extent+0x2c/0x50 [btrfs] run_delalloc_nocow+0x81c/0x8fc [btrfs] btrfs_run_delalloc_range+0xa4/0x390 [btrfs] writepage_delalloc+0xc0/0x1ac [btrfs] __extent_writepage+0xf4/0x370 [btrfs] extent_write_cache_pages+0x288/0x4f4 [btrfs] extent_writepages+0x58/0xe0 [btrfs] btrfs_writepages+0x1c/0x30 [btrfs] do_writepages+0x60/0x110 __filemap_fdatawrite_range+0x108/0x170 filemap_fdatawrite_range+0x20/0x30 btrfs_fdatawrite_range+0x34/0x4dc [btrfs] __btrfs_write_out_cache+0x34c/0x480 [btrfs] btrfs_write_out_cache+0x144/0x220 [btrfs] btrfs_start_dirty_block_groups+0x3ac/0x6b0 [btrfs] btrfs_commit_transaction+0xd0/0xbb4 [btrfs] btrfs_sync_fs+0x64/0x1cc [btrfs] sync_fs_one_sb+0x3c/0x50 iterate_supers+0xcc/0x1d4 ksys_sync+0x6c/0xd0 __arm64_sys_sync+0x1c/0x30 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0x4c/0xd4 do_el0_svc+0x30/0x9c el0_svc+0x2c/0x54 el0_sync_handler+0x1a8/0x1b0 el0_sync+0x198/0x1c0 ---[ end trace 336f67369ae6e0af ]--- [CAUSE] For subpage case, we can have multiple sectors inside a page, this makes it possible for __extent_writepage() to have part of its page submitted before returning. In btrfs/160, we are using dm-dust to emulate write error, this means for certain pages, we could have everything running fine, but at the end of __extent_writepage(), one of the submitted bios fails due to dm-dust. Then the page is marked Error, and we change @ret from 0 to -EIO. This makes the caller extent_write_cache_pages() to error out, without submitting the remaining pages. Furthermore, since we're erroring out for free space cache, it doesn't really care about the error and will update the inode and retry the writeback. Then we re-run the delalloc range, and will try to insert the same delalloc range while previous delalloc range is still hanging there, triggering the above error. [FIX] The proper fix is to handle errors from __extent_writepage() properly, by ending the remaining ordered extent. But that fix needs the following changes: - Know at exactly which sector the error happened Currently __extent_writepage_io() works for the full page, can't return at which sector we hit the error. - Grab the ordered extent covering the failed sector As a hotfix for subpage case, here we unify the error paths in __extent_writepage(). In fact, the "if (PageError(page))" branch never get executed if @ret is still 0 for non-subpage cases. As for non-subpage case, we never submit current page in __extent_writepage(), but only add current page into bio. The bio can only get submitted in next page. Thus we never get PageError() set due to IO failure, thus when we hit the branch, @ret is never 0. By simply removing that @ret assignment, we let subpage case ignore the IO failure, thus only error out for fatal errors just like regular sectorsize. So that IO error won't be treated as fatal error not trigger the hanging OE problem. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: subpage: allow submit_extent_page() to do bio splitQu Wenruo
Current submit_extent_page() just checks if the current page range can be fitted into current bio, and if not, submit then re-add. But this behavior can't handle subpage case at all. For subpage case, the problem is in the page size, 64K, which is also the same size as stripe size. This means, if we can't fit a full 64K into a bio, due to stripe limit, then it won't fit into next bio without crossing stripe either. The proper way to handle it is: - Check how many bytes we can be put into current bio - Put as many bytes as possible into current bio first - Submit current bio - Create a new bio - Add the remaining bytes into the new bio Refactor submit_extent_page() so that it does the above iteration. The main loop inside submit_extent_page() will look like this: cur = pg_offset; while (cur < pg_offset + size) { u32 offset = cur - pg_offset; int added; if (!bio_ctrl->bio) { /* Allocate new bio if needed */ } /* Add as many bytes into the bio */ added = btrfs_bio_add_page(); if (added < size - offset) { /* The current bio is full, submit it */ } cur += added; } Also, since we're doing new bio allocation deep inside the main loop, extract that code into a new helper, alloc_new_bio(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: subpage: fix writeback which does not have ordered extentQu Wenruo
[BUG] When running fsstress with subpage RW support, there are random BUG_ON()s triggered with the following trace: kernel BUG at fs/btrfs/file-item.c:667! Internal error: Oops - BUG: 0 [#1] SMP CPU: 1 PID: 3486 Comm: kworker/u13:2 5.11.0-rc4-custom+ #43 Hardware name: Radxa ROCK Pi 4B (DT) Workqueue: btrfs-worker-high btrfs_work_helper [btrfs] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--) pc : btrfs_csum_one_bio+0x420/0x4e0 [btrfs] lr : btrfs_csum_one_bio+0x400/0x4e0 [btrfs] Call trace: btrfs_csum_one_bio+0x420/0x4e0 [btrfs] btrfs_submit_bio_start+0x20/0x30 [btrfs] run_one_async_start+0x28/0x44 [btrfs] btrfs_work_helper+0x128/0x1b4 [btrfs] process_one_work+0x22c/0x430 worker_thread+0x70/0x3a0 kthread+0x13c/0x140 ret_from_fork+0x10/0x30 [CAUSE] Above BUG_ON() means there is some bio range which doesn't have ordered extent, which indeed is worth a BUG_ON(). Unlike regular sectorsize == PAGE_SIZE case, in subpage we have extra subpage dirty bitmap to record which range is dirty and should be written back. This means, if we submit bio for a subpage range, we do not only need to clear page dirty, but also need to clear subpage dirty bits. In __extent_writepage_io(), we will call btrfs_page_clear_dirty() for any range we submit a bio. But there is loophole, if we hit a range which is beyond i_size, we just call btrfs_writepage_endio_finish_ordered() to finish the ordered io, then break out, without clearing the subpage dirty. This means, if we hit above branch, the subpage dirty bits are still there, if other range of the page get dirtied and we need to writeback that page again, we will submit bio for the old range, leaving a wild bio range which doesn't have ordered extent. [FIX] Fix it by always calling btrfs_page_clear_dirty() in __extent_writepage_io(). Also to avoid such problem from happening again, add a new assert, btrfs_page_assert_not_dirty(), to make sure both page dirty and subpage dirty bits are cleared before exiting __extent_writepage_io(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: reset this_bio_flag to avoid inheriting old flagsQu Wenruo
In btrfs_do_readpage(), we never reset @this_bio_flag after we hit a compressed extent. This is fine, as for PAGE_SIZE == sectorsize case, we can only have one sector for one page, thus @this_bio_flag will only be set at most once. But for subpage case, after hitting a compressed extent, @this_bio_flag will always have EXTENT_BIO_COMPRESSED bit, even we're reading a regular extent. This will lead to various read errors, and causing new ASSERT() in incoming subpage patches, which adds more strict check in btrfs_submit_compressed_read(). Fix it by declaring @this_bio_flag inside the main loop and reset its value for each iteration. 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: switch uptodate to bool in btrfs_writepage_endio_finish_orderedDavid Sterba
The uptodate parameter should be bool, change the type. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: remove unused start and end parameters from btrfs_run_delalloc_range()Qu Wenruo
Since commit d75855b4518b ("btrfs: Remove extent_io_ops::writepage_start_hook") removes the writepage_start_hook() and adds btrfs_writepage_cow_fixup() function, there is no need to follow the old hook parameters. Remove the @start and @end hook, since currently the fixup check is full page check, it doesn't need @start and @end hook. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23btrfs: zoned: remove max_zone_append_size logicJohannes Thumshirn
There used to be a patch in the original series for zoned support which limited the extent size to max_zone_append_size, but this patch has been dropped somewhere around v9. We've decided to go the opposite direction, instead of limiting extents in the first place we split them before submission to comply with the device's limits. Remove the related code, btrfs_fs_info::max_zone_append_size and btrfs_zoned_device_info::max_zone_append_size. This also removes the workaround for dm-crypt introduced in 1d68128c107a ("btrfs: zoned: fail mount if the device does not support zone append") because the fix has been merged as f34ee1dce642 ("dm crypt: Fix zoned block device support"). Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: subpage: fix a rare race between metadata endio and eb freeingQu Wenruo
[BUG] There is a very rare ASSERT() triggering during full fstests run for subpage rw support. No other reproducer so far. The ASSERT() gets triggered for metadata read in btrfs_page_set_uptodate() inside end_page_read(). [CAUSE] There is still a small race window for metadata only, the race could happen like this: T1 | T2 ------------------------------------+----------------------------- end_bio_extent_readpage() | |- btrfs_validate_metadata_buffer() | | |- free_extent_buffer() | | Still have 2 refs | |- end_page_read() | |- if (unlikely(PagePrivate()) | | The page still has Private | | | free_extent_buffer() | | | Only one ref 1, will be | | | released | | |- detach_extent_buffer_page() | | |- btrfs_detach_subpage() |- btrfs_set_page_uptodate() | The page no longer has Private| >>> ASSERT() triggered <<< | This race window is super small, thus pretty hard to hit, even with so many runs of fstests. But the race window is still there, we have to go another way to solve it other than relying on random PagePrivate() check. Data path is not affected, as it will lock the page before reading, while unlocking the page after the last read has finished, thus no race window. [FIX] This patch will fix the bug by repurposing btrfs_subpage::readers. Now btrfs_subpage::readers will be a member shared by both metadata and data. For metadata path, we don't do the page unlock as metadata only relies on extent locking. At the same time, teach page_range_has_eb() to take btrfs_subpage::readers into consideration. So that even if the last eb of a page gets freed, page::private won't be detached as long as there still are pending end_page_read() calls. By this we eliminate the race window, this will slight increase the metadata memory usage, as the page may not be released as frequently as usual. But it should not be a big deal. The code got introduced in ("btrfs: submit read time repair only for each corrupted sector"), but the fix is in a separate patch to keep the problem description and the crash is rare so it should not hurt bisectability. Signed-off-by: Qu Wegruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make __extent_writepage_io() only submit dirty range for subpageQu Wenruo
__extent_writepage_io() function originally just iterates through all the extent maps of a page, and submits any regular extents. This is fine for sectorsize == PAGE_SIZE case, as if a page is dirty, we need to submit the only sector contained in the page. But for subpage case, one dirty page can contain several clean sectors with at least one dirty sector. If __extent_writepage_io() still submit all regular extent maps, it can submit data which is already written to disk. And since such already written data won't have corresponding ordered extents, it will trigger a BUG_ON() in btrfs_csum_one_bio(). Change the behavior of __extent_writepage_io() by finding the first dirty byte in the page, and only submit the dirty range other than the full extent. Since we're also here, also modify the following calls to be subpage compatible: - SetPageError() - end_page_writeback() Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make btrfs_set_range_writeback() subpage compatibleQu Wenruo
Function btrfs_set_range_writeback() currently just sets the page writeback unconditionally. Change it to call the subpage helper so that we can handle both cases well. Since the subpage helpers needs btrfs_fs_info, also change the parameter to accept btrfs_inode. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] 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: update locked page dirty/writeback/error bits in __process_pages_contigQu Wenruo
When __process_pages_contig() gets called for extent_clear_unlock_delalloc(), if we hit the locked page, only Private2 bit is updated, but dirty/writeback/error bits are all skipped. There are several call sites that call extent_clear_unlock_delalloc() with locked_page and PAGE_CLEAR_DIRTY/PAGE_SET_WRITEBACK/PAGE_END_WRITEBACK - cow_file_range() - run_delalloc_nocow() - cow_file_range_async() All for their error handling branches. For those call sites, since we skip the locked page for dirty/error/writeback bit update, the locked page will still have its subpage dirty bit remaining. Normally it's the call sites which locked the page to handle the locked page, but it won't hurt if we also do the update. Especially there are already other call sites doing the same thing by manually passing NULL as locked_page. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make page Ordered bit to be subpage compatibleQu Wenruo
This involves the following modification: - Ordered extent creation This is done in process_one_page(), now PAGE_SET_ORDERED will call subpage helper to do the work. - endio functions This is done in btrfs_mark_ordered_io_finished(). - btrfs_invalidatepage() - btrfs_cleanup_ordered_extents() Use the subpage page helper, and add an extra branch to exit if the locked page have covered the full range. Now the usage of page Ordered flag for ordered extent accounting is fully subpage compatible. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make process_one_page() to handle subpage lockingQu Wenruo
Introduce a new data inodes specific subpage member, writers, to record how many sectors are under page lock for delalloc writing. This member acts pretty much the same as readers, except it's only for delalloc writes. This is important for delalloc code to trace which page can really be freed, as we have cases like run_delalloc_nocow() where we may exit processing nocow range inside a page, but need to exit to do cow half way. In that case, we need a way to determine if we can really unlock a full page. With the new btrfs_subpage::writers, there is a new requirement: - Page locked by process_one_page() must be unlocked by process_one_page() There are still tons of call sites manually lock and unlock a page, without updating btrfs_subpage::writers. So if we lock a page through process_one_page() then it must be unlocked by process_one_page() to keep btrfs_subpage::writers consistent. This will be handled in next patch. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make end_bio_extent_writepage() to be subpage compatibleQu Wenruo
Now in end_bio_extent_writepage(), the only subpage incompatible code is the end_page_writeback(). Just call the subpage helpers. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: make __process_pages_contig() to handle subpage dirty/error/writeback ↵Qu Wenruo
status For __process_pages_contig() and process_one_page(), to handle subpage we only need to pass bytenr in and call subpage helpers to handle dirty/error/writeback status. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: only require sector size alignment for end_bio_extent_writepage()Qu Wenruo
Just like read page, for subpage support we only require sector size alignment. So change the error message condition to only require sector alignment. This should not affect existing code, as for regular sectorsize == PAGE_SIZE case, we are still requiring page alignment. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] 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: refactor page status update into process_one_page()Qu Wenruo
In __process_pages_contig() we update page status according to page_ops. That update process is a bunch of 'if' branches, which lie inside two loops, this makes it pretty hard to expand for later subpage operations. So this patch will extract these operations into its own function, process_one_pages(). Also since we're refactoring __process_pages_contig(), also move the new helper and __process_pages_contig() before the first caller of them, to remove the forward declaration. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] 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>
2021-06-21btrfs: pass bytenr directly to __process_pages_contig()Qu Wenruo
As a preparation for incoming subpage support, we need bytenr passed to __process_pages_contig() directly, not the current page index. So change the parameter and all callers to pass bytenr in. With the modification, here we need to replace the old @index_ret with @processed_end for __process_pages_contig(), but this brings a small problem. Normally we follow the inclusive return value, meaning @processed_end should be the last byte we processed. If parameter @start is 0, and we failed to lock any page, then we would return @processed_end as -1, causing more problems for __unlock_for_delalloc(). So here for @processed_end, we use two different return value patterns. If we have locked any page, @processed_end will be the last byte of locked page. Or it will be @start otherwise. This change will impact lock_delalloc_pages(), so it needs to check @processed_end to only unlock the range if we have locked any. Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64] Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64] Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: rename PagePrivate2 to PageOrdered inside btrfsQu Wenruo
Inside btrfs we use Private2 page status to indicate we have an ordered extent with pending IO for the sector. But the page status name, Private2, tells us nothing about the bit itself, so this patch will rename it to Ordered. And with extra comment about the bit added, so reader who is still uncertain about the page Ordered status, will find the comment pretty easily. 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>
2021-06-21btrfs: 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: make subpage metadata write path call its own endio functionsQu Wenruo
For subpage metadata, we're reusing two functions for subpage metadata write: - end_bio_extent_buffer_writepage() - write_one_eb() But the truth is, for subpage we just call end_bio_subpage_eb_writepage() without using any bit in end_bio_extent_buffer_writepage(). For write_one_eb(), it's pretty similar, but with a small part of code reused. There is really no need to pollute the existing code path if we're not really using most of them. So this patch will do the following change to separate the subpage metadata write path from regular write path by: - Use end_bio_subpage_eb_writepage() directly as endio in write_one_subpage_eb() - Directly call write_one_subpage_eb() in submit_eb_subpage() 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: refactor submit_extent_page() to make bio and its flag tracing easierQu Wenruo
There is a lot of code inside extent_io.c needs both "struct bio **bio_ret" and "unsigned long prev_bio_flags", along with some parameters like "unsigned long bio_flags". Such strange parameters are here for bio assembly. For example, we have such inode page layout: 0 4K 8K 12K |<-- Extent A-->|<- EB->| Then what we do is: - Page [0, 4K) *bio_ret = NULL So we allocate a new bio to bio_ret, Add page [0, 4K) to *bio_ret. - Page [4K, 8K) *bio_ret != NULL We found this page is continuous to *bio_ret, and if we're not at stripe boundary, we add page [4K, 8K) to *bio_ret. - Page [8K, 12K) *bio_ret != NULL But we found this page is not continuous, so we submit *bio_ret, then allocate a new bio, and add page [8K, 12K) to the new bio. This means we need to record both the bio and its bio_flag, but we record them manually using those strange parameter list, other than encapsulating them into their own structure. So this patch will introduce a new structure, btrfs_bio_ctrl, to record both the bio, and its bio_flags. Also, in above case, for all pages added to the bio, we need to check if the new page crosses stripe boundary. This check itself can be time consuming, and we don't really need to do that for each page. This patch also integrates the stripe boundary check into btrfs_bio_ctrl. When a new bio is allocated, the stripe and ordered extent boundary is also calculated, so no matter how large the bio will be, we only calculate the boundaries once, to save some CPU time. The following functions/structures are affected: - struct extent_page_data Replace its bio pointer with structure btrfs_bio_ctrl (embedded structure, not pointer) - end_write_bio() - flush_write_bio() Just change how bio is fetched - btrfs_bio_add_page() Use pre-calculated boundaries instead of re-calculating them. And use @bio_ctrl to replace @bio and @prev_bio_flags. - calc_bio_boundaries() New function - submit_extent_page() callers - btrfs_do_readpage() callers - contiguous_readpages() callers To Use @bio_ctrl to replace @bio and @prev_bio_flags, and how to grab bio. - btrfs_bio_fits_in_ordered_extent() Removed, as now the ordered extent size limit is done at bio allocation time, no need to check for each page range. 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: clean up header members offsets in write helpersDavid Sterba
Move header offsetof() to the expression that calculates the address so it's part of get_eb_offset_in_page where the 2nd parameter is the member offset. Reviewed-by: Qu Wenruo <wqu@suse.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>
2021-06-21btrfs: remove io_failure_record::in_validationQu Wenruo
The io_failure_record::in_validation was introduced to handle failed bio which cross several sectors. In such case, we still need to verify which sectors are corrupted. But since we've changed the way how we handle corrupted sectors, by only submitting repair for each corrupted sector, there is no need for extra validation any more. This patch will cleanup all io_failure_record::in_validation related code. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: submit read time repair only for each corrupted sectorQu Wenruo
Currently btrfs_submit_read_repair() has some extra check on whether the failed bio needs extra validation for repair. But we can avoid all these extra mechanisms if we submit the repair for each sector. By this, each read repair can be easily handled without the need to verify which sector is corrupted. This will also benefit subpage, as one subpage bvec can contain several sectors, making the extra verification more complex. So this patch will: - Introduce repair_one_sector() The main code submitting repair, which is more or less the same as old btrfs_submit_read_repair(). But this time, it only repairs one sector. - Make btrfs_submit_read_repair() to handle sectors differently There are 3 different cases: * Good sector We need to release the page and extent, set the range uptodate. * Bad sector and failed to submit repair bio We need to release the page and extent, but not set the range uptodate. * Bad sector but repair bio submitted The page and extent release will be handled by the submitted repair bio. Nothing needs to be done. Since btrfs_submit_read_repair() will handle the page and extent release now, we need to skip to next bvec even we hit some error. - Change the lifespan of @uptodate in end_bio_extent_readpage() Since now btrfs_submit_read_repair() will handle the full bvec which contains any corruption, we don't need to bother updating @uptodate bit anymore. Just let @uptodate to be local variable inside the main loop, so that any error from one bvec won't affect later bvec. - Only export btrfs_repair_one_sector(), unexport btrfs_submit_read_repair() The only outside caller for read repair is DIO, which already submits its repair for just one sector. Only export btrfs_repair_one_sector() for DIO. This patch will focus on the change on the repair path, the extra validation code is still kept as is, and will be cleaned up later. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21btrfs: correct try_lock_extent() usage in read_extent_buffer_subpage()Goldwyn Rodrigues
try_lock_extent() returns 1 on success or 0 for failure and not an error code. If try_lock_extent() fails, read_extent_buffer_subpage() returns zero indicating subpage extent read success. Return EAGAIN/EWOULDBLOCK if try_lock_extent() fails in locking the extent. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@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: pass start block to btrfs_use_zone_appendJohannes Thumshirn
btrfs_use_zone_append only needs the passed in extent_map's block_start member, so there's no need to pass in the full extent map. This also enables the use of btrfs_use_zone_append in places where we only have a start byte but no extent_map. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-17Merge 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 fiemap to print extents that could get misreported due to internal extent splitting and logical merging for fiemap output - fix RCU stalls during delayed iputs - fix removed dentries still existing after log is synced" * tag 'for-5.13-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix removed dentries still existing after log is synced btrfs: return whole extents in fiemap btrfs: avoid RCU stalls while running delayed iputs btrfs: return 0 for dev_extent_hole_check_zoned hole_start in case of error
2021-05-14btrfs: return whole extents in fiemapBoris Burkov
`xfs_io -c 'fiemap <off> <len>' <file>` can give surprising results on btrfs that differ from xfs. btrfs prints out extents trimmed to fit the user input. If the user's fiemap request has an offset, then rather than returning each whole extent which intersects that range, we also trim the start extent to not have start < off. Documentation in filesystems/fiemap.txt and the xfs_io man page suggests that returning the whole extent is expected. Some cases which all yield the same fiemap in xfs, but not btrfs: dd if=/dev/zero of=$f bs=4k count=1 sudo xfs_io -c 'fiemap 0 1024' $f 0: [0..7]: 26624..26631 sudo xfs_io -c 'fiemap 2048 1024' $f 0: [4..7]: 26628..26631 sudo xfs_io -c 'fiemap 2048 4096' $f 0: [4..7]: 26628..26631 sudo xfs_io -c 'fiemap 3584 512' $f 0: [7..7]: 26631..26631 sudo xfs_io -c 'fiemap 4091 5' $f 0: [7..6]: 26631..26630 I believe this is a consequence of the logic for merging contiguous extents represented by separate extent items. That logic needs to track the last offset as it loops through the extent items, which happens to pick up the start offset on the first iteration, and trim off the beginning of the full extent. To fix it, start `off` at 0 rather than `start` so that we keep the iteration/merging intact without cutting off the start of the extent. after the fix, all the above commands give: 0: [0..7]: 26624..26631 The merging logic is exercised by fstest generic/483, and I have written a new fstest for checking we don't have backwards or zero-length fiemaps for cases like those above. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Boris Burkov <boris@bur.io> 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>
2021-04-20btrfs: more graceful errors/warnings on 32bit systems when reaching limitsQu Wenruo
Btrfs uses internally mapped u64 address space for all its metadata. Due to the page cache limit on 32bit systems, btrfs can't access metadata at or beyond (ULONG_MAX + 1) << PAGE_SHIFT. See how MAX_LFS_FILESIZE and page::index are defined. This is 16T for 4K page size while 256T for 64K page size. Users can have a filesystem which doesn't have metadata beyond the boundary at mount time, but later balance can cause it to create metadata beyond the boundary. And modification to MM layer is unrealistic just for such minor use case. We can't do more than to prevent mounting such filesystem or warn early when the numbers are still within the limits. To address such problem, this patch will introduce the following checks: - Mount time rejection This will reject any fs which has metadata chunk at or beyond the boundary. - Mount time early warning If there is any metadata chunk beyond 5/8th of the boundary, we do an early warning and hope the end user will see it. - Runtime extent buffer rejection If we're going to allocate an extent buffer at or beyond the boundary, reject such request with EOVERFLOW. This is definitely going to cause problems like transaction abort, but we have no better ways. - Runtime extent buffer early warning If an extent buffer beyond 5/8th of the max file size is allocated, do an early warning. Above error/warning message will only be printed once for each fs to reduce dmesg flood. If the mount is rejected, the filesystem will be mountable only on a 64bit host. Link: https://lore.kernel.org/linux-btrfs/1783f16d-7a28-80e6-4c32-fdf19b705ed0@gmx.com/ Reported-by: Erik Jensen <erikjensen@rkjnsn.net> 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: introduce submit_eb_subpage() to submit a subpage metadata pageQu Wenruo
The new function, submit_eb_subpage(), will submit all the dirty extent buffers in the page. The major difference between submit_eb_page() and submit_eb_subpage() is: - How to grab extent buffer Now we use find_extent_buffer_nospinlock() other than using page::private. All other different handling is already done in functions like lock_extent_buffer_for_io() and write_one_eb(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: make lock_extent_buffer_for_io() to be subpage compatibleQu Wenruo
For subpage metadata, we don't use page locking at all. So just skip the page locking part for subpage. The rest of the function can be reused. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: introduce write_one_subpage_eb() functionQu Wenruo
The new function, write_one_subpage_eb(), as a subroutine for subpage metadata write, will handle the extent buffer bio submission. The major differences between the new write_one_subpage_eb() and write_one_eb() is: - No page locking When entering write_one_subpage_eb() the page is no longer locked. We only lock the page for its status update, and unlock immediately. Now we completely rely on extent io tree locking. - Extra bitmap update along with page status update Now page dirty and writeback is controlled by btrfs_subpage::dirty_bitmap and btrfs_subpage::writeback_bitmap. They both follow the schema that any sector is dirty/writeback, then the full page gets dirty/writeback. - When to update the nr_written number Now we take a shortcut, if we have cleared the last dirty bit of the page, we update nr_written. This is not completely perfect, but should emulate the old behavior well enough. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: introduce end_bio_subpage_eb_writepage() functionQu Wenruo
The new function, end_bio_subpage_eb_writepage(), will handle the metadata writeback endio. The major differences involved are: - How to grab extent buffer Now page::private is a pointer to btrfs_subpage, we can no longer grab extent buffer directly. Thus we need to use the bv_offset to locate the extent buffer manually and iterate through the whole range. - Use btrfs_subpage_end_writeback() caller This helper will handle the subpage writeback for us. Since this function is executed under endio context, when grabbing extent buffers it can't grab eb->refs_lock as that lock is not designed to be grabbed under hardirq context. So here introduce a helper, find_extent_buffer_nolock(), for such situation, and convert find_extent_buffer() to use that helper. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: add and use readahead_batch_lengthMatthew Wilcox (Oracle)
Implement readahead_batch_length() to determine the number of bytes in the current batch of readahead pages and use it in btrfs. Also use the readahead_pos to get the offset. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>