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2017-07-10fs/buffer.c: make bh_lru_install() more efficientEric Biggers1-28/+15
To install a buffer_head into the cpu's LRU queue, bh_lru_install() would construct a new copy of the queue and then memcpy it over the real queue. But it's easily possible to do the update in-place, which is faster and simpler. Some work can also be skipped if the buffer_head was already in the queue. As a microbenchmark I timed how long it takes to run sb_getblk() 10,000,000 times alternating between BH_LRU_SIZE + 1 blocks. Effectively, this benchmarks looking up buffer_heads that are in the page cache but not in the LRU: Before this patch: 1.758s After this patch: 1.653s This patch also removes about 350 bytes of compiled code (on x86_64), partly due to removal of the memcpy() which was being inlined+unrolled. Link: http://lkml.kernel.org/r/20161229193445.1913-1-ebiggers3@gmail.com Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-10Merge tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-0/+124
Pull XFS updates from Darrick Wong: "Here are some changes for you for 4.13. For the most part it's fixes for bugs and deadlock problems, and preparation for online fsck in some future merge window. - Avoid quotacheck deadlocks - Fix transaction overflows when bunmapping fragmented files - Refactor directory readahead - Allow admin to configure if ASSERT is fatal - Improve transaction usage detail logging during overflows - Minor cleanups - Don't leak log items when the log shuts down - Remove double-underscore typedefs - Various preparation for online scrubbing - Introduce new error injection configuration sysfs knobs - Refactor dq_get_next to use extent map directly - Fix problems with iterating the page cache for unwritten data - Implement SEEK_{HOLE,DATA} via iomap - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA - Don't use MAXPATHLEN to check on-disk symlink target lengths" * tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (48 commits) xfs: don't crash on unexpected holes in dir/attr btrees xfs: rename MAXPATHLEN to XFS_SYMLINK_MAXLEN xfs: fix contiguous dquot chunk iteration livelock xfs: Switch to iomap for SEEK_HOLE / SEEK_DATA vfs: Add iomap_seek_hole and iomap_seek_data helpers vfs: Add page_cache_seek_hole_data helper xfs: remove a whitespace-only line from xfs_fs_get_nextdqblk xfs: rewrite xfs_dq_get_next_id using xfs_iext_lookup_extent xfs: Check for m_errortag initialization in xfs_errortag_test xfs: grab dquots without taking the ilock xfs: fix semicolon.cocci warnings xfs: Don't clear SGID when inheriting ACLs xfs: free cowblocks and retry on buffered write ENOSPC xfs: replace log_badcrc_factor knob with error injection tag xfs: convert drop_writes to use the errortag mechanism xfs: remove unneeded parameter from XFS_TEST_ERROR xfs: expose errortag knobs via sysfs xfs: make errortag a per-mountpoint structure xfs: free uncommitted transactions during log recovery xfs: don't allow bmap on rt files ...
2017-07-09Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The first major feature for ext4 this merge window is the largedir feature, which allows ext4 directories to support over 2 billion directory entries (assuming ~64 byte file names; in practice, users will run into practical performance limits first.) This feature was originally written by the Lustre team, and credit goes to Artem Blagodarenko from Seagate for getting this feature upstream. The second major major feature allows ext4 to support extended attribute values up to 64k. This feature was also originally from Lustre, and has been enhanced by Tahsin Erdogan from Google with a deduplication feature so that if multiple files have the same xattr value (for example, Windows ACL's stored by Samba), only one copy will be stored on disk for encoding and caching efficiency. We also have the usual set of bug fixes, cleanups, and optimizations" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits) ext4: fix spelling mistake: "prellocated" -> "preallocated" ext4: fix __ext4_new_inode() journal credits calculation ext4: skip ext4_init_security() and encryption on ea_inodes fs: generic_block_bmap(): initialize all of the fields in the temp bh ext4: change fast symlink test to not rely on i_blocks ext4: require key for truncate(2) of encrypted file ext4: don't bother checking for encryption key in ->mmap() ext4: check return value of kstrtoull correctly in reserved_clusters_store ext4: fix off-by-one fsmap error on 1k block filesystems ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry() ext4: return EIO on read error in ext4_find_entry ext4: forbid encrypting root directory ext4: send parallel discards on commit completions ext4: avoid unnecessary stalls in ext4_evict_inode() ext4: add nombcache mount option ext4: strong binding of xattr inode references ext4: eliminate xattr entry e_hash recalculation for removes ext4: reserve space for xattr entries/names quota: add get_inode_usage callback to transfer multi-inode charges ext4: xattr inode deduplication ...
2017-07-07Merge tag 'for-linus-v4.13-2' of ↵Linus Torvalds1-7/+13
git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux Pull Writeback error handling updates from Jeff Layton: "This pile represents the bulk of the writeback error handling fixes that I have for this cycle. Some of the earlier patches in this pile may look trivial but they are prerequisites for later patches in the series. The aim of this set is to improve how we track and report writeback errors to userland. Most applications that care about data integrity will periodically call fsync/fdatasync/msync to ensure that their writes have made it to the backing store. For a very long time, we have tracked writeback errors using two flags in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a writeback error occurs (via mapping_set_error) and are cleared as a side-effect of filemap_check_errors (as you noted yesterday). This model really sucks for userland. Only the first task to call fsync (or msync or fdatasync) will see the error. Any subsequent task calling fsync on a file will get back 0 (unless another writeback error occurs in the interim). If I have several tasks writing to a file and calling fsync to ensure that their writes got stored, then I need to have them coordinate with one another. That's difficult enough, but in a world of containerized setups that coordination may even not be possible. But wait...it gets worse! The calls to filemap_check_errors can be buried pretty far down in the call stack, and there are internal callers of filemap_write_and_wait and the like that also end up clearing those errors. Many of those callers ignore the error return from that function or return it to userland at nonsensical times (e.g. truncate() or stat()). If I get back -EIO on a truncate, there is no reason to think that it was because some previous writeback failed, and a subsequent fsync() will (incorrectly) return 0. This pile aims to do three things: 1) ensure that when a writeback error occurs that that error will be reported to userland on a subsequent fsync/fdatasync/msync call, regardless of what internal callers are doing 2) report writeback errors on all file descriptions that were open at the time that the error occurred. This is a user-visible change, but I think most applications are written to assume this behavior anyway. Those that aren't are unlikely to be hurt by it. 3) document what filesystems should do when there is a writeback error. Today, there is very little consistency between them, and a lot of cargo-cult copying. We need to make it very clear what filesystems should do in this situation. To achieve this, the set adds a new data type (errseq_t) and then builds new writeback error tracking infrastructure around that. Once all of that is in place, we change the filesystems to use the new infrastructure for reporting wb errors to userland. Note that this is just the initial foray into cleaning up this mess. There is a lot of work remaining here: 1) convert the rest of the filesystems in a similar fashion. Once the initial set is in, then I think most other fs' will be fairly simple to convert. Hopefully most of those can in via individual filesystem trees. 2) convert internal waiters on writeback to use errseq_t for detecting errors instead of relying on the AS_* flags. I have some draft patches for this for ext4, but they are not quite ready for prime time yet. This was a discussion topic this year at LSF/MM too. If you're interested in the gory details, LWN has some good articles about this: https://lwn.net/Articles/718734/ https://lwn.net/Articles/724307/" * tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: btrfs: minimal conversion to errseq_t writeback error reporting on fsync xfs: minimal conversion to errseq_t writeback error reporting ext4: use errseq_t based error handling for reporting data writeback errors fs: convert __generic_file_fsync to use errseq_t based reporting block: convert to errseq_t based writeback error tracking dax: set errors in mapping when writeback fails Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error fs: new infrastructure for writeback error handling and reporting lib: add errseq_t type and infrastructure for handling it mm: don't TestClearPageError in __filemap_fdatawait_range mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails jbd2: don't clear and reset errors after waiting on writeback buffer: set errors in mapping at the time that the error occurs fs: check for writeback errors after syncing out buffers in generic_file_fsync buffer: use mapping_set_error instead of setting the flag mm: fix mapping_set_error call in me_pagecache_dirty
2017-07-06buffer: set errors in mapping at the time that the error occursJeff Layton1-7/+13
I noticed on xfs that I could still sometimes get back an error on fsync on a fd that was opened after the error condition had been cleared. The problem is that the buffer code sets the write_io_error flag and then later checks that flag to set the error in the mapping. That flag perisists for quite a while however. If the file is later opened with O_TRUNC, the buffers will then be invalidated and the mapping's error set such that a subsequent fsync will return error. I think this is incorrect, as there was no writeback between the open and fsync. Add a new mark_buffer_write_io_error operation that sets the flag and the error in the mapping at the same time. Replace all calls to set_buffer_write_io_error with mark_buffer_write_io_error, and remove the places that check this flag in order to set the error in the mapping. This sets the error in the mapping earlier, at the time that it's first detected. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2017-07-06buffer: use mapping_set_error instead of setting the flagJeff Layton1-1/+1
Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-07-05fs: generic_block_bmap(): initialize all of the fields in the temp bhAlexander Potapenko1-4/+4
KMSAN (KernelMemorySanitizer, a new error detection tool) reports the use of uninitialized memory in ext4_update_bh_state(): ================================================================== BUG: KMSAN: use of unitialized memory CPU: 3 PID: 1 Comm: swapper/0 Tainted: G B 4.8.0-rc6+ #597 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 0000000000000282 ffff88003cc96f68 ffffffff81f30856 0000003000000008 ffff88003cc96f78 0000000000000096 ffffffff8169742a ffff88003cc96ff8 ffffffff812fc1fc 0000000000000008 ffff88003a1980e8 0000000100000000 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81f30856>] dump_stack+0xa6/0xc0 lib/dump_stack.c:51 [<ffffffff812fc1fc>] kmsan_report+0x1ec/0x300 mm/kmsan/kmsan.c:? [<ffffffff812fc33b>] __msan_warning+0x2b/0x40 ??:? [< inline >] ext4_update_bh_state fs/ext4/inode.c:727 [<ffffffff8169742a>] _ext4_get_block+0x6ca/0x8a0 fs/ext4/inode.c:759 [<ffffffff81696d4c>] ext4_get_block+0x8c/0xa0 fs/ext4/inode.c:769 [<ffffffff814a2d36>] generic_block_bmap+0x246/0x2b0 fs/buffer.c:2991 [<ffffffff816ca30e>] ext4_bmap+0x5ee/0x660 fs/ext4/inode.c:3177 ... origin description: ----tmp@generic_block_bmap ================================================================== (the line numbers are relative to 4.8-rc6, but the bug persists upstream) The local |tmp| is created in generic_block_bmap() and then passed into ext4_bmap() => ext4_get_block() => _ext4_get_block() => ext4_update_bh_state(). Along the way tmp.b_page is never initialized before ext4_update_bh_state() checks its value. [ Use the approach suggested by Kees Cook of initializing the whole bh structure.] Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-07-02vfs: Add page_cache_seek_hole_data helperAndreas Gruenbacher1-0/+124
Both ext4 and xfs implement seeking for the next hole or piece of data in unwritten extents by scanning the page cache, and both versions share the same bug when iterating the buffers of a page: the start offset into the page isn't taken into account, so when a page fits more than two filesystem blocks, things will go wrong. For example, on a filesystem with a block size of 1k, the following command will fail: xfs_io -f -c "falloc 0 4k" \ -c "pwrite 1k 1k" \ -c "pwrite 3k 1k" \ -c "seek -a -r 0" foo In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048, SEEK_DATA) will return the correct result. Introduce a generic vfs helper for seeking in the page cache that gets this right. The next commits will replace the filesystem specific implementations. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> [hch: dropped the export] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-06-27fs: add support for buffered writeback to pass down write hintsJens Axboe1-5/+8
Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-09block: switch bios to blk_status_tChristoph Hellwig1-1/+1
Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-09Merge branch 'work.misc' of ↵Linus Torvalds1-14/+5
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted bits and pieces from various people. No common topic in this pile, sorry" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs/affs: add rename exchange fs/affs: add rename2 to prepare multiple methods Make stat/lstat/fstatat pass AT_NO_AUTOMOUNT to vfs_statx() fs: don't set *REFERENCED on single use objects fs: compat: Remove warning from COMPATIBLE_IOCTL remove pointless extern of atime_need_update_rcu() fs: completely ignore unknown open flags fs: add a VALID_OPEN_FLAGS fs: remove _submit_bh() fs: constify tree_descr arrays passed to simple_fill_super() fs: drop duplicate header percpu-rwsem.h fs/affs: bugfix: Write files greater than page size on OFS fs/affs: bugfix: enable writes on OFS disks fs/affs: remove node generation check fs/affs: import amigaffs.h fs/affs: bugfix: make symbolic links work again
2017-05-08fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flagTetsuo Handa1-8/+5
Commit afddba49d18f ("fs: introduce write_begin, write_end, and perform_write aops") introduced AOP_FLAG_UNINTERRUPTIBLE flag which was checked in pagecache_write_begin(), but that check was removed by 4e02ed4b4a2f ("fs: remove prepare_write/commit_write"). Between these two commits, commit d9414774dc0c ("cifs: Convert cifs to new aops.") added a check in cifs_write_begin(), but that check was soon removed by commit a98ee8c1c707 ("[CIFS] fix regression in cifs_write_begin/cifs_write_end"). Therefore, AOP_FLAG_UNINTERRUPTIBLE flag is checked nowhere. Let's remove this flag. This patch has no functionality changes. Link: http://lkml.kernel.org/r/1489294781-53494-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Nick Piggin <npiggin@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-26fs: remove _submit_bh()Eric Biggers1-14/+5
_submit_bh() allowed submitting a buffer_head for I/O using custom bio_flags. It used to be used by jbd to set BIO_SNAP_STABLE, introduced by commit 713685111774 ("mm: make snapshotting pages for stable writes a per-bio operation"). However, the code and flag has since been removed and no _submit_bh() users remain. These days, bio_flags are mostly used internally by the block layer to track the state of bio's. As such, it doesn't really make sense for filesystems to use them instead of op_flags when wanting special behavior for block requests. Therefore, remove _submit_bh() and trim the bio_flags argument from submit_bh_wbc(). Cc: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-02sched/headers: Prepare for the reduction of <linux/sched.h>'s signal API ↵Ingo Molnar1-0/+1
dependency Instead of including the full <linux/signal.h>, we are going to include the types-only <linux/signal_types.h> header in <linux/sched.h>, to further decouple the scheduler header from the signal headers. This means that various files which relied on the full <linux/signal.h> need to be updated to gain an explicit dependency on it. Update the code that relies on sched.h's inclusion of the <linux/signal.h> header. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-27fs: add i_blocksize()Fabian Frederick1-6/+6
Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs branch. This patch also fixes multiple checkpatch warnings: WARNING: Prefer 'unsigned int' to bare use of 'unsigned' Thanks to Andrew Morton for suggesting more appropriate function instead of macro. [geliangtang@gmail.com: truncate: use i_blocksize()] Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-02clean_bdev_aliases: Prevent cleaning blocks that are not in block rangeChandan Rajendra1-1/+1
The first block to be cleaned may start at a non-zero page offset. In such a scenario clean_bdev_aliases() will end up cleaning blocks that do not fall in the range of blocks to be cleaned. This commit fixes the issue by skipping blocks that do not fall in valid block range. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Eryu Guan <eguan@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-14Merge branch 'for-4.10/fs-unmap' of git://git.kernel.dk/linux-blockLinus Torvalds1-31/+73
Pull fs meta data unmap optimization from Jens Axboe: "A series from Jan Kara, providing a more efficient way for unmapping meta data from in the buffer cache than doing it block-by-block. Provide a general helper that existing callers can use" * 'for-4.10/fs-unmap' of git://git.kernel.dk/linux-block: fs: Remove unmap_underlying_metadata fs: Add helper to clean bdev aliases under a bh and use it ext2: Use clean_bdev_aliases() instead of iteration ext4: Use clean_bdev_aliases() instead of iteration direct-io: Use clean_bdev_aliases() instead of handmade iteration fs: Provide function to unmap metadata for a range of blocks
2016-12-13Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-blockLinus Torvalds1-5/+5
Pull block layer updates from Jens Axboe: "This is the main block pull request this series. Contrary to previous release, I've kept the core and driver changes in the same branch. We always ended up having dependencies between the two for obvious reasons, so makes more sense to keep them together. That said, I'll probably try and keep more topical branches going forward, especially for cycles that end up being as busy as this one. The major parts of this pull request is: - Improved support for O_DIRECT on block devices, with a small private implementation instead of using the pig that is fs/direct-io.c. From Christoph. - Request completion tracking in a scalable fashion. This is utilized by two components in this pull, the new hybrid polling and the writeback queue throttling code. - Improved support for polling with O_DIRECT, adding a hybrid mode that combines pure polling with an initial sleep. From me. - Support for automatic throttling of writeback queues on the block side. This uses feedback from the device completion latencies to scale the queue on the block side up or down. From me. - Support from SMR drives in the block layer and for SD. From Hannes and Shaun. - Multi-connection support for nbd. From Josef. - Cleanup of request and bio flags, so we have a clear split between which are bio (or rq) private, and which ones are shared. From Christoph. - A set of patches from Bart, that improve how we handle queue stopping and starting in blk-mq. - Support for WRITE_ZEROES from Chaitanya. - Lightnvm updates from Javier/Matias. - Supoort for FC for the nvme-over-fabrics code. From James Smart. - A bunch of fixes from a whole slew of people, too many to name here" * 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits) blk-stat: fix a few cases of missing batch flushing blk-flush: run the queue when inserting blk-mq flush elevator: make the rqhash helpers exported blk-mq: abstract out blk_mq_dispatch_rq_list() helper blk-mq: add blk_mq_start_stopped_hw_queue() block: improve handling of the magic discard payload blk-wbt: don't throttle discard or write zeroes nbd: use dev_err_ratelimited in io path nbd: reset the setup task for NBD_CLEAR_SOCK nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME nvme-fabrics: Add target support for FC transport nvme-fabrics: Add host support for FC transport nvme-fabrics: Add FC transport LLDD api definitions nvme-fabrics: Add FC transport FC-NVME definitions nvme-fabrics: Add FC transport error codes to nvme.h Add type 0x28 NVME type code to scsi fc headers nvme-fabrics: patch target code in prep for FC transport support nvme-fabrics: set sqe.command_id in core not transports parser: add u64 number parser nvme-rdma: align to generic ib_event logging helper ...
2016-11-09fs/buffer: Convert to hotplug state machineSebastian Andrzej Siewior1-10/+6
Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-fsdevel@vger.kernel.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20161103145021.28528-2-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-04fs: Remove unmap_underlying_metadataJan Kara1-32/+0
Nobody is using this function anymore. Remove it. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-04fs: Add helper to clean bdev aliases under a bh and use itJan Kara1-5/+3
Add a helper function that clears buffer heads from a block device aliasing passed bh. Use this helper function from filesystems instead of the original unmap_underlying_metadata() to save some boiler plate code and also have a better name for the functionalily since it is not unmapping anything for a *long* time. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-04fs: Provide function to unmap metadata for a range of blocksJan Kara1-0/+76
Provide function equivalent to unmap_underlying_metadata() for a range of blocks. We somewhat optimize the function to use pagevec lookups instead of looking up buffer heads one by one and use page lock to pin buffer heads instead of mapping's private_lock to improve scalability. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-02writeback: add wbc_to_write_flags()Jens Axboe1-1/+1
Add wbc_to_write_flags(), which returns the write modifier flags to use, based on a struct writeback_control. No functional changes in this patch, but it prepares us for factoring other wbc fields for write type. Signed-off-by: Jens Axboe <axboe@fb.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-11-01block,fs: use REQ_* flags directlyChristoph Hellwig1-4/+4
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags directly. Where applicable this also drops usage of the bio_set_op_attrs wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-10-28block: better op and flags encodingChristoph Hellwig1-1/+1
Now that we don't need the common flags to overflow outside the range of a 32-bit type we can encode them the same way for both the bio and request fields. This in addition allows us to place the operation first (and make some room for more ops while we're at it) and to stop having to shift around the operation values. In addition this allows passing around only one value in the block layer instead of two (and eventuall also in the file systems, but we can do that later) and thus clean up a lot of code. Last but not least this allows decreasing the size of the cmd_flags field in struct request to 32-bits. Various functions passing this value could also be updated, but I'd like to avoid the churn for now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-10-11fs: use mapping_set_error instead of opencoded set_bitMichal Hocko1-2/+2
The mapping_set_error() helper sets the correct AS_ flag for the mapping so there is no reason to open code it. Use the helper directly. [akpm@linux-foundation.org: be honest about conversion from -ENXIO to -EIO] Link: http://lkml.kernel.org/r/20160912111608.2588-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-27fs/buffer.c: make __getblk_slow() staticEric Biggers1-2/+1
__getblk_slow() was exported to modules in commit 3b5e6454aaf6 ("fs/buffer.c: support buffer cache allocations with gfp modifiers"). This seems to have been a mistake, as no users were introduced nor was the function declared in a header. Change it back to 'static'. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-27Merge tag 'xfs-for-linus-4.8-rc1' of ↵Linus Torvalds1-5/+71
git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs Pull xfs updates from Dave Chinner: "The major addition is the new iomap based block mapping infrastructure. We've been kicking this about locally for years, but there are other filesystems want to use it too (e.g. gfs2). Now it is fully working, reviewed and ready for merge and be used by other filesystems. There are a lot of other fixes and cleanups in the tree, but those are XFS internal things and none are of the scale or visibility of the iomap changes. See below for details. I am likely to send another pull request next week - we're just about ready to merge some new functionality (on disk block->owner reverse mapping infrastructure), but that's a huge chunk of code (74 files changed, 7283 insertions(+), 1114 deletions(-)) so I'm keeping that separate to all the "normal" pull request changes so they don't get lost in the noise. Summary of changes in this update: - generic iomap based IO path infrastructure - generic iomap based fiemap implementation - xfs iomap based Io path implementation - buffer error handling fixes - tracking of in flight buffer IO for unmount serialisation - direct IO and DAX io path separation and simplification - shortform directory format definition changes for wider platform compatibility - various buffer cache fixes - cleanups in preparation for rmap merge - error injection cleanups and fixes - log item format buffer memory allocation restructuring to prevent rare OOM reclaim deadlocks - sparse inode chunks are now fully supported" * tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (53 commits) xfs: remove EXPERIMENTAL tag from sparse inode feature xfs: bufferhead chains are invalid after end_page_writeback xfs: allocate log vector buffers outside CIL context lock libxfs: directory node splitting does not have an extra block xfs: remove dax code from object file when disabled xfs: skip dirty pages in ->releasepage() xfs: remove __arch_pack xfs: kill xfs_dir2_inou_t xfs: kill xfs_dir2_sf_off_t xfs: split direct I/O and DAX path xfs: direct calls in the direct I/O path xfs: stop using generic_file_read_iter for direct I/O xfs: split xfs_file_read_iter into buffered and direct I/O helpers xfs: remove s_maxbytes enforcement in xfs_file_read_iter xfs: kill ioflags xfs: don't pass ioflags around in the ioctl path xfs: track and serialize in-flight async buffers against unmount xfs: exclude never-released buffers from buftarg I/O accounting xfs: don't reset b_retries to 0 on every failure xfs: remove extraneous buffer flag changes ...
2016-07-26Merge branch 'for-4.8/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-6/+6
Pull block driver updates from Jens Axboe: "This branch also contains core changes. I've come to the conclusion that from 4.9 and forward, I'll be doing just a single branch. We often have dependencies between core and drivers, and it's hard to always split them up appropriately without pulling core into drivers when that happens. That said, this contains: - separate secure erase type for the core block layer, from Christoph. - set of discard fixes, from Christoph. - bio shrinking fixes from Christoph, as a followup up to the op/flags change in the core branch. - map and append request fixes from Christoph. - NVMeF (NVMe over Fabrics) code from Christoph. This is pretty exciting! - nvme-loop fixes from Arnd. - removal of ->driverfs_dev from Dan, after providing a device_add_disk() helper. - bcache fixes from Bhaktipriya and Yijing. - cdrom subchannel read fix from Vchannaiah. - set of lightnvm updates from Wenwei, Matias, Johannes, and Javier. - set of drbd updates and fixes from Fabian, Lars, and Philipp. - mg_disk error path fix from Bart. - user notification for failed device add for loop, from Minfei. - NVMe in general: + NVMe delay quirk from Guilherme. + SR-IOV support and command retry limits from Keith. + fix for memory-less NUMA node from Masayoshi. + use UINT_MAX for discard sectors, from Minfei. + cancel IO fixes from Ming. + don't allocate unused major, from Neil. + error code fixup from Dan. + use constants for PSDT/FUSE from James. + variable init fix from Jay. + fabrics fixes from Ming, Sagi, and Wei. + various fixes" * 'for-4.8/drivers' of git://git.kernel.dk/linux-block: (115 commits) nvme/pci: Provide SR-IOV support nvme: initialize variable before logical OR'ing it block: unexport various bio mapping helpers scsi/osd: open code blk_make_request target: stop using blk_make_request block: simplify and export blk_rq_append_bio block: ensure bios return from blk_get_request are properly initialized virtio_blk: use blk_rq_map_kern memstick: don't allow REQ_TYPE_BLOCK_PC requests block: shrink bio size again block: simplify and cleanup bvec pool handling block: get rid of bio_rw and READA block: don't ignore -EOPNOTSUPP blkdev_issue_write_same block: introduce BLKDEV_DISCARD_ZERO to fix zeroout NVMe: don't allocate unused nvme_major nvme: avoid crashes when node 0 is memoryless node. nvme: Limit command retries loop: Make user notify for adding loop device failed nvme-loop: fix nvme-loop Kconfig dependencies nvmet: fix return value check in nvmet_subsys_alloc() ...
2016-07-26Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-blockLinus Torvalds1-33/+36
Pull core block updates from Jens Axboe: - the big change is the cleanup from Mike Christie, cleaning up our uses of command types and modified flags. This is what will throw some merge conflicts - regression fix for the above for btrfs, from Vincent - following up to the above, better packing of struct request from Christoph - a 2038 fix for blktrace from Arnd - a few trivial/spelling fixes from Bart Van Assche - a front merge check fix from Damien, which could cause issues on SMR drives - Atari partition fix from Gabriel - convert cfq to highres timers, since jiffies isn't granular enough for some devices these days. From Jan and Jeff - CFQ priority boost fix idle classes, from me - cleanup series from Ming, improving our bio/bvec iteration - a direct issue fix for blk-mq from Omar - fix for plug merging not involving the IO scheduler, like we do for other types of merges. From Tahsin - expose DAX type internally and through sysfs. From Toshi and Yigal * 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits) block: Fix front merge check block: do not merge requests without consulting with io scheduler block: Fix spelling in a source code comment block: expose QUEUE_FLAG_DAX in sysfs block: add QUEUE_FLAG_DAX for devices to advertise their DAX support Btrfs: fix comparison in __btrfs_map_block() block: atari: Return early for unsupported sector size Doc: block: Fix a typo in queue-sysfs.txt cfq-iosched: Charge at least 1 jiffie instead of 1 ns cfq-iosched: Fix regression in bonnie++ rewrite performance cfq-iosched: Convert slice_resid from u64 to s64 block: Convert fifo_time from ulong to u64 blktrace: avoid using timespec block/blk-cgroup.c: Declare local symbols static block/bio-integrity.c: Add #include "blk.h" block/partition-generic.c: Remove a set-but-not-used variable block: bio: kill BIO_MAX_SIZE cfq-iosched: temporarily boost queue priority for idle classes block: drbd: avoid to use BIO_MAX_SIZE block: bio: remove BIO_MAX_SECTORS ...
2016-07-20block: get rid of bio_rw and READAChristoph Hellwig1-6/+6
These two are confusing leftover of the old world order, combining values of the REQ_OP_ and REQ_ namespaces. For callers that don't special case we mostly just replace bi_rw with bio_data_dir or op_is_write, except for the few cases where a switch over the REQ_OP_ values makes more sense. Any check for READA is replaced with an explicit check for REQ_RAHEAD. Also remove the READA alias for REQ_RAHEAD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-27fs: export __block_write_full_pageBenjamin Marzinski1-1/+2
gfs2 needs to be able to skip the check to see if a page is outside of the file size when writing it out. gfs2 can get into a situation where it needs to flush its in-memory log to disk while a truncate is in progress. If the file being trucated has data journaling enabled, it is possible that there are data blocks in the log that are past the end of the file. gfs can't finish the log flush without either writing these blocks out or revoking them. Otherwise, if the node crashed, it could overwrite subsequent changes made by other nodes in the cluster when it's journal was replayed. Unfortunately, there is no way to add log entries to the log during a flush. So gfs2 simply writes out the page instead. This situation can only occur when the truncate code still has the file locked exclusively, and hasn't marked this block as free in the metadata (which happens later in truc_dealloc). After gfs2 writes this page out, the truncation code will shortly invalidate it and write out any revokes if necessary. In order to make this work, gfs2 needs to be able to skip the check for writes outside the file size. Since the check exists in block_write_full_page, this patch exports __block_write_full_page, which doesn't have the check. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-21fs: introduce iomap infrastructureChristoph Hellwig1-5/+71
Add infrastructure for multipage buffered writes. This is implemented using an main iterator that applies an actor function to a range that can be written. This infrastucture is used to implement a buffered write helper, one to zero file ranges and one to implement the ->page_mkwrite VM operations. All of them borrow a fair amount of code from fs/buffers. for now by using an internal version of __block_write_begin that gets passed an iomap and builds the corresponding buffer head. The file system is gets a set of paired ->iomap_begin and ->iomap_end calls which allow it to map/reserve a range and get a notification once the write code is finished with it. Based on earlier code from Dave Chinner. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-06-07fs: have ll_rw_block users pass in op and flags separatelyMike Christie1-9/+10
This has ll_rw_block users pass in the operation and flags separately, so ll_rw_block can setup the bio op and bi_rw flags on the bio that is submitted. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07fs: have submit_bh users pass in op and flags separatelyMike Christie1-26/+27
This has submit_bh users pass in the operation and flags separately, so submit_bh_wbc can setup the bio op and bi_rw flags on the bio that is submitted. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07block/fs/drivers: remove rw argument from submit_bioMike Christie1-1/+2
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw instead of passing it in. This makes that use the same as generic_make_request and how we set the other bio fields. Signed-off-by: Mike Christie <mchristi@redhat.com> Fixed up fs/ext4/crypto.c Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-19mm, page_alloc: avoid looking up the first zone in a zonelist twiceMel Gorman1-5/+5
The allocator fast path looks up the first usable zone in a zonelist and then get_page_from_freelist does the same job in the zonelist iterator. This patch preserves the necessary information. 4.6.0-rc2 4.6.0-rc2 fastmark-v1r20 initonce-v1r20 Min alloc-odr0-1 364.00 ( 0.00%) 359.00 ( 1.37%) Min alloc-odr0-2 262.00 ( 0.00%) 260.00 ( 0.76%) Min alloc-odr0-4 214.00 ( 0.00%) 214.00 ( 0.00%) Min alloc-odr0-8 186.00 ( 0.00%) 186.00 ( 0.00%) Min alloc-odr0-16 173.00 ( 0.00%) 173.00 ( 0.00%) Min alloc-odr0-32 165.00 ( 0.00%) 165.00 ( 0.00%) Min alloc-odr0-64 161.00 ( 0.00%) 162.00 ( -0.62%) Min alloc-odr0-128 159.00 ( 0.00%) 161.00 ( -1.26%) Min alloc-odr0-256 168.00 ( 0.00%) 170.00 ( -1.19%) Min alloc-odr0-512 180.00 ( 0.00%) 181.00 ( -0.56%) Min alloc-odr0-1024 190.00 ( 0.00%) 190.00 ( 0.00%) Min alloc-odr0-2048 196.00 ( 0.00%) 196.00 ( 0.00%) Min alloc-odr0-4096 202.00 ( 0.00%) 202.00 ( 0.00%) Min alloc-odr0-8192 206.00 ( 0.00%) 205.00 ( 0.49%) Min alloc-odr0-16384 206.00 ( 0.00%) 205.00 ( 0.49%) The benefit is negligible and the results are within the noise but each cycle counts. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov1-50/+50
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15mm: simplify lock_page_memcg()Johannes Weiner1-10/+8
Now that migration doesn't clear page->mem_cgroup of live pages anymore, it's safe to make lock_page_memcg() and the memcg stat functions take pages, and spare the callers from memcg objects. [akpm@linux-foundation.org: fix warnings] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15mm: memcontrol: generalize locking for the page->mem_cgroup bindingJohannes Weiner1-7/+7
These patches tag the page cache radix tree eviction entries with the memcg an evicted page belonged to, thus making per-cgroup LRU reclaim work properly and be as adaptive to new cache workingsets as global reclaim already is. This should have been part of the original thrash detection patch series, but was deferred due to the complexity of those patches. This patch (of 5): So far the only sites that needed to exclude charge migration to stabilize page->mem_cgroup have been per-cgroup page statistics, hence the name mem_cgroup_begin_page_stat(). But per-cgroup thrash detection will add another site that needs to ensure page->mem_cgroup lifetime. Rename these locking functions to the more generic lock_page_memcg() and unlock_page_memcg(). Since charge migration is a cgroup1 feature only, we might be able to delete it at some point, and these now easy to identify locking sites along with it. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-06fs: use block_device name vsprintf helperDmitry Monakhov1-15/+6
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-11vfs: remove unused wrapper block_page_mkwrite()Ross Zwisler1-22/+2
The function currently called "__block_page_mkwrite()" used to be called "block_page_mkwrite()" until a wrapper for this function was added by: commit 24da4fab5a61 ("vfs: Create __block_page_mkwrite() helper passing error values back") This wrapper, the current "block_page_mkwrite()", is currently unused. __block_page_mkwrite() is used directly by ext4, nilfs2 and xfs. Remove the unused wrapper, rename __block_page_mkwrite() back to block_page_mkwrite() and update the comment above block_page_mkwrite(). Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Jan Kara <jack@suse.com> Cc: Jan Kara <jack@suse.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-06mm, fs: introduce mapping_gfp_constraint()Michal Hocko1-1/+1
There are many places which use mapping_gfp_mask to restrict a more generic gfp mask which would be used for allocations which are not directly related to the page cache but they are performed in the same context. Let's introduce a helper function which makes the restriction explicit and easier to track. This patch doesn't introduce any functional changes. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michal Hocko <mhocko@suse.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-13fs: use helper bio_add_page() instead of open coding on bi_io_vecKent Overstreet1-5/+2
Call pre-defined helper bio_add_page() instead of open coding for iterating through bi_io_vec[]. Doing that, it's possible to make some parts in filesystems and mm/page_io.c simpler than before. Acked-by: Dave Kleikamp <shaggy@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: add more description in commit message] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-29block: manipulate bio->bi_flags through helpersJens Axboe1-1/+1
Some places use helpers now, others don't. We only have the 'is set' helper, add helpers for setting and clearing flags too. It was a bit of a mess of atomic vs non-atomic access. With BIO_UPTODATE gone, we don't have any risk of concurrent access to the flags. So relax the restriction and don't make any of them atomic. The flags that do have serialization issues (reffed and chained), we already handle those separately. Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-29block: add a bi_error field to struct bioChristoph Hellwig1-2/+2
Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02buffer: remove unusued 'ret' variableJens Axboe1-1/+0
Merge hickup on my part, due to a clash between the writeback changes and the EOPNOTSUPP removal in _submit_bh(). Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02writeback: implement foreign cgroup inode detectionTejun Heo1-1/+3
As concurrent write sharing of an inode is expected to be very rare and memcg only tracks page ownership on first-use basis severely confining the usefulness of such sharing, cgroup writeback tracks ownership per-inode. While the support for concurrent write sharing of an inode is deemed unnecessary, an inode being written to by different cgroups at different points in time is a lot more common, and, more importantly, charging only by first-use can too readily lead to grossly incorrect behaviors (single foreign page can lead to gigabytes of writeback to be incorrectly attributed). To resolve this issue, cgroup writeback detects the majority dirtier of an inode and will transfer the ownership to it. To avoid unnnecessary oscillation, the detection mechanism keeps track of history and gives out the switch verdict only if the foreign usage pattern is stable over a certain amount of time and/or writeback attempts. The detection mechanism has fairly low space and computation overhead. It adds 8 bytes to struct inode (one int and two u16's) and minimal amount of calculation per IO. The detection mechanism converges to the correct answer usually in several seconds of IO time when there's a clear majority dirtier. Even when there isn't, it can reach an acceptable answer fairly quickly under most circumstances. Please see wb_detach_inode() for more details. This patch only implements detection. Following patches will implement actual switching. v2: wbc_account_io() now checks whether the wbc is associated with a wb before dereferencing it. This can happen when pageout() is writing pages directly without going through the usual writeback path. As pageout() path is single-threaded, we don't want it to be blocked behind a slow cgroup and ultimately want it to delegate actual writing to the usual writeback path. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02writeback: make writeback_control track the inode being written backTejun Heo1-13/+12
Currently, for cgroup writeback, the IO submission paths directly associate the bio's with the blkcg from inode_to_wb_blkcg_css(); however, it'd be necessary to keep more writeback context to implement foreign inode writeback detection. wbc (writeback_control) is the natural fit for the extra context - it persists throughout the writeback of each inode and is passed all the way down to IO submission paths. This patch adds wbc_attach_and_unlock_inode(), wbc_detach_inode(), and wbc_attach_fdatawrite_inode() which are used to associate wbc with the inode being written back. IO submission paths now use wbc_init_bio() instead of directly associating bio's with blkcg themselves. This leaves inode_to_wb_blkcg_css() w/o any user. The function is removed. wbc currently only tracks the associated wb (bdi_writeback). Future patches will add more for foreign inode detection. The association is established under i_lock which will be depended upon when migrating foreign inodes to other wb's. As currently, once established, inode to wb association never changes, going through wbc when initializing bio's doesn't cause any behavior changes. v2: submit_blk_blkcg() now checks whether the wbc is associated with a wb before dereferencing it. This can happen when pageout() is writing pages directly without going through the usual writeback path. As pageout() path is single-threaded, we don't want it to be blocked behind a slow cgroup and ultimately want it to delegate actual writing to the usual writeback path. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02buffer, writeback: make __block_write_full_page() honor cgroup writebackTejun Heo1-6/+20
[__]block_write_full_page() is used to implement ->writepage in various filesystems. All writeback logic is now updated to handle cgroup writeback and the block cgroup to issue IOs for is encoded in writeback_control and can be retrieved from the inode; however, [__]block_write_full_page() currently ignores the blkcg indicated by inode and issues all bio's without explicit blkcg association. This patch adds submit_bh_blkcg() which associates the bio with the specified blkio cgroup before issuing and uses it in __block_write_full_page() so that the issued bio's are associated with inode_to_wb_blkcg_css(inode). v2: Updated for per-inode wb association. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@fb.com>
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