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2023-08-29Merge tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: "Pretty quiet round for this release. This contains: - Add support for zoned storage to ublk (Andreas, Ming) - Series improving performance for drivers that mark themselves as needing a blocking context for issue (Bart) - Cleanup the flush logic (Chengming) - sed opal keyring support (Greg) - Fixes and improvements to the integrity support (Jinyoung) - Add some exports for bcachefs that we can hopefully delete again in the future (Kent) - deadline throttling fix (Zhiguo) - Series allowing building the kernel without buffer_head support (Christoph) - Sanitize the bio page adding flow (Christoph) - Write back cache fixes (Christoph) - MD updates via Song: - Fix perf regression for raid0 large sequential writes (Jan) - Fix split bio iostat for raid0 (David) - Various raid1 fixes (Heinz, Xueshi) - raid6test build fixes (WANG) - Deprecate bitmap file support (Christoph) - Fix deadlock with md sync thread (Yu) - Refactor md io accounting (Yu) - Various non-urgent fixes (Li, Yu, Jack) - Various fixes and cleanups (Arnd, Azeem, Chengming, Damien, Li, Ming, Nitesh, Ruan, Tejun, Thomas, Xu)" * tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux: (113 commits) block: use strscpy() to instead of strncpy() block: sed-opal: keyring support for SED keys block: sed-opal: Implement IOC_OPAL_REVERT_LSP block: sed-opal: Implement IOC_OPAL_DISCOVERY blk-mq: prealloc tags when increase tagset nr_hw_queues blk-mq: delete redundant tagset map update when fallback blk-mq: fix tags leak when shrink nr_hw_queues ublk: zoned: support REQ_OP_ZONE_RESET_ALL md: raid0: account for split bio in iostat accounting md/raid0: Fix performance regression for large sequential writes md/raid0: Factor out helper for mapping and submitting a bio md raid1: allow writebehind to work on any leg device set WriteMostly md/raid1: hold the barrier until handle_read_error() finishes md/raid1: free the r1bio before waiting for blocked rdev md/raid1: call free_r1bio() before allow_barrier() in raid_end_bio_io() blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init drivers/rnbd: restore sysfs interface to rnbd-client md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid() raid6: test: only check for Altivec if building on powerpc hosts raid6: test: make sure all intermediate and artifact files are .gitignored ...
2023-08-02fs: add CONFIG_BUFFER_HEADChristoph Hellwig
Add a new config option that controls building the buffer_head code, and select it from all file systems and stacking drivers that need it. For the block device nodes and alternative iomap based buffered I/O path is provided when buffer_head support is not enabled, and iomap needs a a small tweak to define the IOMAP_F_BUFFER_HEAD flag to 0 to not call into the buffer_head code when it doesn't exist. Otherwise this is just Kconfig and ifdef changes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20230801172201.1923299-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-07-25iomap: Add per-block dirty state tracking to improve performanceRitesh Harjani (IBM)
When filesystem blocksize is less than folio size (either with mapping_large_folio_support() or with blocksize < pagesize) and when the folio is uptodate in pagecache, then even a byte write can cause an entire folio to be written to disk during writeback. This happens because we currently don't have a mechanism to track per-block dirty state within struct iomap_folio_state. We currently only track uptodate state. This patch implements support for tracking per-block dirty state in iomap_folio_state->state bitmap. This should help improve the filesystem write performance and help reduce write amplification. Performance testing of below fio workload reveals ~16x performance improvement using nvme with XFS (4k blocksize) on Power (64K pagesize) FIO reported write bw scores improved from around ~28 MBps to ~452 MBps. 1. <test_randwrite.fio> [global] ioengine=psync rw=randwrite overwrite=1 pre_read=1 direct=0 bs=4k size=1G dir=./ numjobs=8 fdatasync=1 runtime=60 iodepth=64 group_reporting=1 [fio-run] 2. Also our internal performance team reported that this patch improves their database workload performance by around ~83% (with XFS on Power) Reported-by: Aravinda Herle <araherle@in.ibm.com> Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2023-07-24iomap: Create large folios in the buffered write pathMatthew Wilcox (Oracle)
Use the size of the write as a hint for the size of the folio to create. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2023-04-21iomap: Remove IOMAP_DIO_NOSYNC unused dio flagRitesh Harjani (IBM)
IOMAP_DIO_NOSYNC earlier was added for use in btrfs. But it seems for aio dsync writes this is not useful anyway. For aio dsync case, we we queue the request and return -EIOCBQUEUED. Now, since IOMAP_DIO_NOSYNC doesn't let iomap_dio_complete() to call generic_write_sync(), hence we may lose the sync write. Hence kill this flag as it is not in use by any FS now. Tested-by: Disha Goel <disgoel@linux.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-02-22Merge tag 'iomap-6.3-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull iomap updates from Darrick Wong: "This is mostly rearranging things to make life easier for gfs2, nothing all that mindblowing for this release. - Change when the iomap page_done function is called so that we still have a locked folio in the success case. This fixes a writeback race in gfs2 - Change when the iomap page_prepare function is called so that gfs2 can recover from OOM scenarios more gracefully - Rename the iomap page_ops to folio_ops, since they operate on folios now" * tag 'iomap-6.3-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: iomap: Rename page_ops to folio_ops iomap: Rename page_prepare handler to get_folio iomap: Add __iomap_get_folio helper iomap/gfs2: Get page in page_prepare handler iomap: Add iomap_get_folio helper iomap: Rename page_done handler to put_folio iomap/gfs2: Unlock and put folio in page_done handler iomap: Add __iomap_put_folio helper
2023-02-15iomap: remove IOMAP_F_ZONE_APPENDChristoph Hellwig
No users left now that btrfs takes REQ_OP_WRITE bios from iomap and splits and converts them to REQ_OP_ZONE_APPEND internally. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-18iomap: Rename page_ops to folio_opsAndreas Gruenbacher
The operations in struct page_ops all operate on folios, so rename struct page_ops to struct folio_ops. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> [djwong: port around not removing iomap_valid] Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-01-18iomap: Rename page_prepare handler to get_folioAndreas Gruenbacher
The ->page_prepare() handler in struct iomap_page_ops is now somewhat misnamed, so rename it to ->get_folio(). Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-01-18iomap/gfs2: Get page in page_prepare handlerAndreas Gruenbacher
Change the iomap ->page_prepare() handler to get and return a locked folio instead of doing that in iomap_write_begin(). This allows to recover from out-of-memory situations in ->page_prepare(), which eliminates the corresponding error handling code in iomap_write_begin(). The ->put_folio() handler now also isn't called with NULL as the folio value anymore. Filesystems are expected to use the iomap_get_folio() helper for getting locked folios in their ->page_prepare() handlers. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-01-18iomap: Add iomap_get_folio helperAndreas Gruenbacher
Add an iomap_get_folio() helper that gets a folio reference based on an iomap iterator and an offset into the address space. Use it in iomap_write_begin(). Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-01-18iomap: Rename page_done handler to put_folioAndreas Gruenbacher
The ->page_done() handler in struct iomap_page_ops is now somewhat misnamed in that it mainly deals with unlocking and putting a folio, so rename it to ->put_folio(). Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-01-18iomap/gfs2: Unlock and put folio in page_done handlerAndreas Gruenbacher
When an iomap defines a ->page_done() handler in its page_ops, delegate unlocking the folio and putting the folio reference to that handler. This allows to fix a race between journaled data writes and folio writeback in gfs2: before this change, gfs2_iomap_page_done() was called after unlocking the folio, so writeback could start writing back the folio's buffers before they could be marked for writing to the journal. Also, try_to_free_buffers() could free the buffers before gfs2_iomap_page_done() was done adding the buffers to the current current transaction. With this change, gfs2_iomap_page_done() adds the buffers to the current transaction while the folio is still locked, so the problems described above can no longer occur. The only current user of ->page_done() is gfs2, so other filesystems are not affected. To catch out any out-of-tree users, switch from a page to a folio in ->page_done(). Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-11-29iomap: write iomap validity checksDave Chinner
A recent multithreaded write data corruption has been uncovered in the iomap write code. The core of the problem is partial folio writes can be flushed to disk while a new racing write can map it and fill the rest of the page: writeback new write allocate blocks blocks are unwritten submit IO ..... map blocks iomap indicates UNWRITTEN range loop { lock folio copyin data ..... IO completes runs unwritten extent conv blocks are marked written <iomap now stale> get next folio } Now add memory pressure such that memory reclaim evicts the partially written folio that has already been written to disk. When the new write finally gets to the last partial page of the new write, it does not find it in cache, so it instantiates a new page, sees the iomap is unwritten, and zeros the part of the page that it does not have data from. This overwrites the data on disk that was originally written. The full description of the corruption mechanism can be found here: https://lore.kernel.org/linux-xfs/20220817093627.GZ3600936@dread.disaster.area/ To solve this problem, we need to check whether the iomap is still valid after we lock each folio during the write. We have to do it after we lock the page so that we don't end up with state changes occurring while we wait for the folio to be locked. Hence we need a mechanism to be able to check that the cached iomap is still valid (similar to what we already do in buffered writeback), and we need a way for ->begin_write to back out and tell the high level iomap iterator that we need to remap the remaining write range. The iomap needs to grow some storage for the validity cookie that the filesystem provides to travel with the iomap. XFS, in particular, also needs to know some more information about what the iomap maps (attribute extents rather than file data extents) to for the validity cookie to cover all the types of iomaps we might need to validate. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-11-23xfs,iomap: move delalloc punching to iomapDave Chinner
Because that's what Christoph wants for this error handling path only XFS uses. It requires a new iomap export for handling errors over delalloc ranges. This is basically the XFS code as is stands, but even though Christoph wants this as iomap funcitonality, we still have to call it from the filesystem specific ->iomap_end callback, and call into the iomap code with yet another filesystem specific callback to punch the delalloc extent within the defined ranges. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-08-11Merge tag 'iomap-6.0-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull more iomap updates from Darrick Wong: "In the past 10 days or so I've not heard any ZOMG STOP style complaints about removing ->writepage support from gfs2 or zonefs, so here's the pull request removing them (and the underlying fs iomap support) from the kernel: - Remove iomap_writepage and all callers, since the mm apparently never called the zonefs or gfs2 writepage functions" * tag 'iomap-6.0-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: iomap: remove iomap_writepage zonefs: remove ->writepage gfs2: remove ->writepage gfs2: stop using generic_writepages in gfs2_ail1_start_one
2022-08-03Merge tag 'pull-work.iov_iter-base' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs iov_iter updates from Al Viro: "Part 1 - isolated cleanups and optimizations. One of the goals is to reduce the overhead of using ->read_iter() and ->write_iter() instead of ->read()/->write(). new_sync_{read,write}() has a surprising amount of overhead, in particular inside iocb_flags(). That's the explanation for the beginning of the series is in this pile; it's not directly iov_iter-related, but it's a part of the same work..." * tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: first_iovec_segment(): just return address iov_iter: massage calling conventions for first_{iovec,bvec}_segment() iov_iter: first_{iovec,bvec}_segment() - simplify a bit iov_iter: lift dealing with maxpages out of first_{iovec,bvec}_segment() iov_iter_get_pages{,_alloc}(): cap the maxsize with MAX_RW_COUNT iov_iter_bvec_advance(): don't bother with bvec_iter copy_page_{to,from}_iter(): switch iovec variants to generic keep iocb_flags() result cached in struct file iocb: delay evaluation of IS_SYNC(...) until we want to check IOCB_DSYNC struct file: use anonymous union member for rcuhead and llist btrfs: use IOMAP_DIO_NOSYNC teach iomap_dio_rw() to suppress dsync No need of likely/unlikely on calls of check_copy_size()
2022-08-02mm/migrate: Add filemap_migrate_folio()Matthew Wilcox (Oracle)
There is nothing iomap-specific about iomap_migratepage(), and it fits a pattern used by several other filesystems, so move it to mm/migrate.c, convert it to be filemap_migrate_folio() and convert the iomap filesystems to use it. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-22iomap: remove iomap_writepageChristoph Hellwig
Unused now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-06-10teach iomap_dio_rw() to suppress dsyncAl Viro
New flag, equivalent to removal of IOCB_DSYNC from iocb flags. This mimics what btrfs is doing (and that's what btrfs will switch to). However, I'm not at all sure that we want to suppress REQ_FUA for those - all btrfs hack really cares about is suppression of generic_write_sync(). For now let's keep the existing behaviour, but I really want to hear more detailed arguments pro or contra. [folded brain fix from willy] Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-05-24Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds
Pull page cache updates from Matthew Wilcox: - Appoint myself page cache maintainer - Fix how scsicam uses the page cache - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS - Remove the AOP flags entirely - Remove pagecache_write_begin() and pagecache_write_end() - Documentation updates - Convert several address_space operations to use folios: - is_dirty_writeback - readpage becomes read_folio - releasepage becomes release_folio - freepage becomes free_folio - Change filler_t to require a struct file pointer be the first argument like ->read_folio * tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits) nilfs2: Fix some kernel-doc comments Appoint myself page cache maintainer fs: Remove aops->freepage secretmem: Convert to free_folio nfs: Convert to free_folio orangefs: Convert to free_folio fs: Add free_folio address space operation fs: Convert drop_buffers() to use a folio fs: Change try_to_free_buffers() to take a folio jbd2: Convert release_buffer_page() to use a folio jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio reiserfs: Convert release_buffer_page() to use a folio fs: Remove last vestiges of releasepage ubifs: Convert to release_folio reiserfs: Convert to release_folio orangefs: Convert to release_folio ocfs2: Convert to release_folio nilfs2: Remove comment about releasepage nfs: Convert to release_folio jfs: Convert to release_folio ...
2022-05-16iomap: add per-iomap_iter private dataChristoph Hellwig
Allow the file system to keep state for all iterations. For now only wire it up for direct I/O as there is an immediate need for it there. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16iomap: allow the file system to provide a bio_set for direct I/OChristoph Hellwig
Allow the file system to provide a specific bio_set for allocating direct I/O bios. This will allow file systems that use the ->submit_io hook to stash away additional information for file system use. To make use of this additional space for information in the completion path, the file system needs to override the ->bi_end_io callback and then call back into iomap, so export iomap_dio_bio_end_io for that. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-09iomap: Convert to release_folioMatthew Wilcox (Oracle)
Change all the filesystems which used iomap_releasepage to use the new function. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-09fs: Convert iomap_readpage to iomap_read_folioMatthew Wilcox (Oracle)
A straightforward conversion as iomap_readpage already worked in folios. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-03-15iomap: Remove iomap_invalidatepage()Matthew Wilcox (Oracle)
Use iomap_invalidate_folio() in all the iomap-based filesystems and rename the iomap_invalidatepage tracepoint. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-14fs: Convert is_partially_uptodate to foliosMatthew Wilcox (Oracle)
Since the uptodate property is maintained on a per-folio basis, the is_partially_uptodate method should also take a folio. Fix the types at the same time so it's clear that it returns true/false and takes the count in bytes, not blocks. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-01-26xfs, iomap: limit individual ioend chain lengths in writebackDave Chinner
Trond Myklebust reported soft lockups in XFS IO completion such as this: watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [kworker/12:1:3106] CPU: 12 PID: 3106 Comm: kworker/12:1 Not tainted 4.18.0-305.10.2.el8_4.x86_64 #1 Workqueue: xfs-conv/md127 xfs_end_io [xfs] RIP: 0010:_raw_spin_unlock_irqrestore+0x11/0x20 Call Trace: wake_up_page_bit+0x8a/0x110 iomap_finish_ioend+0xd7/0x1c0 iomap_finish_ioends+0x7f/0xb0 xfs_end_ioend+0x6b/0x100 [xfs] xfs_end_io+0xb9/0xe0 [xfs] process_one_work+0x1a7/0x360 worker_thread+0x1fa/0x390 kthread+0x116/0x130 ret_from_fork+0x35/0x40 Ioends are processed as an atomic completion unit when all the chained bios in the ioend have completed their IO. Logically contiguous ioends can also be merged and completed as a single, larger unit. Both of these things can be problematic as both the bio chains per ioend and the size of the merged ioends processed as a single completion are both unbound. If we have a large sequential dirty region in the page cache, write_cache_pages() will keep feeding us sequential pages and we will keep mapping them into ioends and bios until we get a dirty page at a non-sequential file offset. These large sequential runs can will result in bio and ioend chaining to optimise the io patterns. The pages iunder writeback are pinned within these chains until the submission chaining is broken, allowing the entire chain to be completed. This can result in huge chains being processed in IO completion context. We get deep bio chaining if we have large contiguous physical extents. We will keep adding pages to the current bio until it is full, then we'll chain a new bio to keep adding pages for writeback. Hence we can build bio chains that map millions of pages and tens of gigabytes of RAM if the page cache contains big enough contiguous dirty file regions. This long bio chain pins those pages until the final bio in the chain completes and the ioend can iterate all the chained bios and complete them. OTOH, if we have a physically fragmented file, we end up submitting one ioend per physical fragment that each have a small bio or bio chain attached to them. We do not chain these at IO submission time, but instead we chain them at completion time based on file offset via iomap_ioend_try_merge(). Hence we can end up with unbound ioend chains being built via completion merging. XFS can then do COW remapping or unwritten extent conversion on that merged chain, which involves walking an extent fragment at a time and running a transaction to modify the physical extent information. IOWs, we merge all the discontiguous ioends together into a contiguous file range, only to then process them individually as discontiguous extents. This extent manipulation is computationally expensive and can run in a tight loop, so merging logically contiguous but physically discontigous ioends gains us nothing except for hiding the fact the fact we broke the ioends up into individual physical extents at submission and then need to loop over those individual physical extents at completion. Hence we need to have mechanisms to limit ioend sizes and to break up completion processing of large merged ioend chains: 1. bio chains per ioend need to be bound in length. Pure overwrites go straight to iomap_finish_ioend() in softirq context with the exact bio chain attached to the ioend by submission. Hence the only way to prevent long holdoffs here is to bound ioend submission sizes because we can't reschedule in softirq context. 2. iomap_finish_ioends() has to handle unbound merged ioend chains correctly. This relies on any one call to iomap_finish_ioend() being bound in runtime so that cond_resched() can be issued regularly as the long ioend chain is processed. i.e. this relies on mechanism #1 to limit individual ioend sizes to work correctly. 3. filesystems have to loop over the merged ioends to process physical extent manipulations. This means they can loop internally, and so we break merging at physical extent boundaries so the filesystem can easily insert reschedule points between individual extent manipulations. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reported-and-tested-by: Trond Myklebust <trondmy@hammerspace.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-01-12Merge tag 'libnvdimm-for-5.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull dax and libnvdimm updates from Dan Williams: "The bulk of this is a rework of the dax_operations API after discovering the obstacles it posed to the work-in-progress DAX+reflink support for XFS and other copy-on-write filesystem mechanics. Primarily the need to plumb a block_device through the API to handle partition offsets was a sticking point and Christoph untangled that dependency in addition to other cleanups to make landing the DAX+reflink support easier. The DAX_PMEM_COMPAT option has been around for 4 years and not only are distributions shipping userspace that understand the current configuration API, but some are not even bothering to turn this option on anymore, so it seems a good time to remove it per the deprecation schedule. Recall that this was added after the device-dax subsystem moved from /sys/class/dax to /sys/bus/dax for its sysfs organization. All recent functionality depends on /sys/bus/dax. Some other miscellaneous cleanups and reflink prep patches are included as well. Summary: - Simplify the dax_operations API: - Eliminate bdev_dax_pgoff() in favor of the filesystem maintaining and applying a partition offset to all its DAX iomap operations. - Remove wrappers and device-mapper stacked callbacks for ->copy_from_iter() and ->copy_to_iter() in favor of moving block_device relative offset responsibility to the dax_direct_access() caller. - Remove the need for an @bdev in filesystem-DAX infrastructure - Remove unused uio helpers copy_from_iter_flushcache() and copy_mc_to_iter() as only the non-check_copy_size() versions are used for DAX. - Prepare XFS for the pending (next merge window) DAX+reflink support - Remove deprecated DEV_DAX_PMEM_COMPAT support - Cleanup a straggling misuse of the GUID api" * tag 'libnvdimm-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (38 commits) iomap: Fix error handling in iomap_zero_iter() ACPI: NFIT: Import GUID before use dax: remove the copy_from_iter and copy_to_iter methods dax: remove the DAXDEV_F_SYNC flag dax: simplify dax_synchronous and set_dax_synchronous uio: remove copy_from_iter_flushcache() and copy_mc_to_iter() iomap: turn the byte variable in iomap_zero_iter into a ssize_t memremap: remove support for external pgmap refcounts fsdax: don't require CONFIG_BLOCK iomap: build the block based code conditionally dax: fix up some of the block device related ifdefs fsdax: shift partition offset handling into the file systems dax: return the partition offset from fs_dax_get_by_bdev iomap: add a IOMAP_DAX flag xfs: pass the mapping flags to xfs_bmbt_to_iomap xfs: use xfs_direct_write_iomap_ops for DAX zeroing xfs: move dax device handling into xfs_{alloc,free}_buftarg ext4: cleanup the dax handling in ext4_fill_super ext2: cleanup the dax handling in ext2_fill_super fsdax: decouple zeroing from the iomap buffered I/O code ...
2021-12-18iomap,xfs: Convert ->discard_page to ->discard_folioMatthew Wilcox (Oracle)
XFS has the only implementation of ->discard_page today, so convert it to use folios in the same patch as converting the API. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-12-16iomap: Add iomap_invalidate_folioMatthew Wilcox (Oracle)
Keep iomap_invalidatepage around as a wrapper for use in address_space operations. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-12-04iomap: add a IOMAP_DAX flagChristoph Hellwig
Add a flag so that the file system can easily detect DAX operations based just on the iomap operation requested instead of looking at inode state using IS_DAX. This will be needed to apply the to be added partition offset only for operations that actually use DAX, but not things like fiemap that are based on the block device. In the long run it should also allow turning the bdev, dax_dev and inline_data into a union. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20211129102203.2243509-25-hch@lst.de Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-11-02Merge tag 'gfs2-v5.15-rc5-mmap-fault' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 mmap + page fault deadlocks fixes from Andreas Gruenbacher: "Functions gfs2_file_read_iter and gfs2_file_write_iter are both accessing the user buffer to write to or read from while holding the inode glock. In the most basic deadlock scenario, that buffer will not be resident and it will be mapped to the same file. Accessing the buffer will trigger a page fault, and gfs2 will deadlock trying to take the same inode glock again while trying to handle that fault. Fix that and similar, more complex scenarios by disabling page faults while accessing user buffers. To make this work, introduce a small amount of new infrastructure and fix some bugs that didn't trigger so far, with page faults enabled" * tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: Fix mmap + page fault deadlocks for direct I/O iov_iter: Introduce nofault flag to disable page faults gup: Introduce FOLL_NOFAULT flag to disable page faults iomap: Add done_before argument to iomap_dio_rw iomap: Support partial direct I/O on user copy failures iomap: Fix iomap_dio_rw return value for user copies gfs2: Fix mmap + page fault deadlocks for buffered I/O gfs2: Eliminate ip->i_gh gfs2: Move the inode glock locking to gfs2_file_buffered_write gfs2: Introduce flag for glock holder auto-demotion gfs2: Clean up function may_grant gfs2: Add wrapper for iomap_file_buffered_write iov_iter: Introduce fault_in_iov_iter_writeable iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable} powerpc/kvm: Fix kvm_use_magic_page iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value
2021-10-24iomap: Add done_before argument to iomap_dio_rwAndreas Gruenbacher
Add a done_before argument to iomap_dio_rw that indicates how much of the request has already been transferred. When the request succeeds, we report that done_before additional bytes were tranferred. This is useful for finishing a request asynchronously when part of the request has already been completed synchronously. We'll use that to allow iomap_dio_rw to be used with page faults disabled: when a page fault occurs while submitting a request, we synchronously complete the part of the request that has already been submitted. The caller can then take care of the page fault and call iomap_dio_rw again for the rest of the request, passing in the number of bytes already tranferred. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-10-24iomap: Support partial direct I/O on user copy failuresAndreas Gruenbacher
In iomap_dio_rw, when iomap_apply returns an -EFAULT error and the IOMAP_DIO_PARTIAL flag is set, complete the request synchronously and return a partial result. This allows the caller to deal with the page fault and retry the remainder of the request. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2021-10-18block: switch polling to be bio basedChristoph Hellwig
Replace the blk_poll interface that requires the caller to keep a queue and cookie from the submissions with polling based on the bio. Polling for the bio itself leads to a few advantages: - the cookie construction can made entirely private in blk-mq.c - the caller does not need to remember the request_queue and cookie separately and thus sidesteps their lifetime issues - keeping the device and the cookie inside the bio allows to trivially support polling BIOs remapping by stacking drivers - a lot of code to propagate the cookie back up the submission path can be removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: replace the spin argument to blk_iopoll with a flags argumentChristoph Hellwig
Switch the boolean spin argument to blk_poll to passing a set of flags instead. This will allow to control polling behavior in a more fine grained way. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Link: https://lore.kernel.org/r/20211012111226.760968-10-hch@lst.de [axboe: adapt to changed io_uring iopoll] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-16iomap: constify iomap_iter_srcmapChristoph Hellwig
The srcmap returned from iomap_iter_srcmap is never modified, so mark the iomap returned from it const and constify a lot of code that never modifies the iomap. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: rework unshare flagChristoph Hellwig
Instead of another internal flags namespace inside of buffered-io.c, just pass a UNSHARE hint in the main iomap flags field. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: remove iomap_applyChristoph Hellwig
iomap_apply is unused now, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> [djwong: rebase this patch to preserve git history of iomap loop control] Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-08-16iomap: switch __iomap_dio_rw to use iomap_iterChristoph Hellwig
Switch __iomap_dio_rw to use iomap_iter. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: add the new iomap_iter modelChristoph Hellwig
The iomap_iter struct provides a convenient way to package up and maintain all the arguments to the various mapping and operation functions. It is operated on using the iomap_iter() function that is called in loop until the whole range has been processed. Compared to the existing iomap_apply() function this avoid an indirect call for each iteration. For now iomap_iter() calls back into the existing ->iomap_begin and ->iomap_end methods, but in the future this could be further optimized to avoid indirect calls entirely. Based on an earlier patch from Matthew Wilcox <willy@infradead.org>. Signed-off-by: Christoph Hellwig <hch@lst.de> [djwong: add to apply.c to preserve git history of iomap loop control] Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-08-16iomap: mark the iomap argument to iomap_inline_data_valid constChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: mark the iomap argument to iomap_inline_data constChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: mark the iomap argument to iomap_sector constChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16iomap: remove the iomap arguments to ->page_{prepare,done}Christoph Hellwig
These aren't actually used by the only instance implementing the methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-03iomap: support reading inline data from non-zero posGao Xiang
The existing inline data support only works for cases where the entire file is stored as inline data. For larger files, EROFS stores the initial blocks separately and the remainder of the file ("file tail") adjacent to the inode. Generalise inline data to allow reading the inline file tail. Tails may not cross a page boundary in memory. We currently have no filesystems that support tails and writing, so that case is currently disabled (see iomap_write_begin_inline). Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-06-29iomap: use __set_page_dirty_nobuffersMatthew Wilcox (Oracle)
The only difference between iomap_set_page_dirty() and __set_page_dirty_nobuffers() is that the latter includes a debugging check that a !Uptodate page has private data. Link: https://lkml.kernel.org/r/20210615162342.1669332-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-04iomap: remove unused private field from ioendBrian Foster
The only remaining user of ->io_private is the generic ioend merging infrastructure. The only user of that is XFS, which no longer sets ->io_private or passes an associated merge callback. Remove the unused parameter and the ->io_private field. CC: linux-fsdevel@vger.kernel.org Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-02-21Merge tag 'iomap-5.12-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull iomap updates from Darrick Wong: "The big change in this cycle is some new code to make it possible for XFS to try unaligned directio overwrites without taking locks. If the block is fully written and within EOF (i.e. doesn't require any further fs intervention) then we can let the unlocked write proceed. If not, we fall back to synchronizing direct writes. Summary: - Adjust the final parameter of iomap_dio_rw. - Add a new flag to request that iomap directio writes return EAGAIN if the write is not a pure overwrite within EOF; this will be used to reduce lock contention with unaligned direct writes on XFS. - Amend XFS' directio code to eliminate exclusive locking for unaligned direct writes if the circumstances permit" * tag 'iomap-5.12-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: reduce exclusive locking on unaligned dio xfs: split the unaligned DIO write code out xfs: improve the reflink_bounce_dio_write tracepoint xfs: simplify the read/write tracepoints xfs: remove the buffered I/O fallback assert xfs: cleanup the read/write helper naming xfs: make xfs_file_aio_write_checks IOCB_NOWAIT-aware xfs: factor out a xfs_ilock_iocb helper iomap: add a IOMAP_DIO_OVERWRITE_ONLY flag iomap: pass a flags argument to iomap_dio_rw iomap: rename the flags variable in __iomap_dio_rw