kernel/linux.git/include/linux/iomap.h, branch v6.1.168

iomap: turn iomap_want_unshare_iter into an inline function

2024-11-08T15:26:42+00:00

[ Upstream commit 6db388585e486c0261aeef55f8bc63a9b45756c0 ] iomap_want_unshare_iter currently sits in fs/iomap/buffered-io.c, which depends on CONFIG_BLOCK. It is also in used in fs/dax.c whіch has no such dependency. Given that it is a trivial check turn it into an inline in include/linux/iomap.h to fix the DAX && !BLOCK build. Fixes: 6ef6a0e821d3 ("iomap: share iomap_unshare_iter predicate code with fsdax") Reported-by: kernel test robot Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20241015041350.118403-1-hch@lst.de Reviewed-by: Brian Foster Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

iomap: share iomap_unshare_iter predicate code with fsdax

2024-11-08T15:26:42+00:00

[ Upstream commit 6ef6a0e821d3dad6bf8a5d5508762dba9042c84b ] The predicate code that iomap_unshare_iter uses to decide if it's really needs to unshare a file range mapping should be shared with the fsdax version, because right now they're opencoded and inconsistent. Note that we simplify the predicate logic a bit -- we no longer allow unsharing of inline data mappings, but there aren't any filesystems that allow shared inline data currently. This is a fix in the sense that it should have been ported to fsdax. Fixes: b53fdb215d13 ("iomap: improve shared block detection in iomap_unshare_iter") Signed-off-by: Darrick J. Wong Link: https://lore.kernel.org/r/172796813294.1131942.15762084021076932620.stgit@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner Stable-dep-of: 50793801fc7f ("fsdax: dax_unshare_iter needs to copy entire blocks") Signed-off-by: Sasha Levin

iomap: write iomap validity checks

2024-05-25T14:21:31+00:00

[ Upstream commit d7b64041164ca177170191d2ad775da074ab2926 ] 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 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 Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Leah Rumancik Acked-by: Darrick J. Wong Signed-off-by: Greg Kroah-Hartman

xfs,iomap: move delalloc punching to iomap

2024-05-25T14:21:31+00:00

[ Upstream commit 9c7babf94a0d686b552e53aded8d4703d1b8b92b ] 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 Reviewed-by: Darrick J. Wong Signed-off-by: Leah Rumancik Acked-by: Darrick J. Wong Signed-off-by: Greg Kroah-Hartman

Merge tag 'iomap-6.0-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2022-08-11T20:11:49+00:00

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

Merge tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-08-03T20:50:22+00:00

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()

mm/migrate: Add filemap_migrate_folio()

2022-08-02T16:34:04+00:00

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) Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong

iomap: remove iomap_writepage

2022-07-22T17:59:17+00:00

Unused now. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

teach iomap_dio_rw() to suppress dsync

2022-06-10T20:03:35+00:00

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 Reviewed-by: Christian Brauner (Microsoft) Signed-off-by: Al Viro

Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache

2022-05-25T02:55:07+00:00

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 ...