kernel.git/fs/direct-io.c, branch linux-3.14.y

block: Abstract out bvec iterator

2013-11-24T06:33:47Z

Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Geert Uytterhoeven Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "Ed L. Cashin" Cc: Nick Piggin Cc: Lars Ellenberg Cc: Jiri Kosina Cc: Matthew Wilcox Cc: Geoff Levand Cc: Yehuda Sadeh Cc: Sage Weil Cc: Alex Elder Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris Cc: Philip Kelleher Cc: Rusty Russell Cc: "Michael S. Tsirkin" Cc: Konrad Rzeszutek Wilk Cc: Jeremy Fitzhardinge Cc: Neil Brown Cc: Alasdair Kergon Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: Boaz Harrosh Cc: Benny Halevy Cc: "James E.J. Bottomley" Cc: Greg Kroah-Hartman Cc: "Nicholas A. Bellinger" Cc: Alexander Viro Cc: Chris Mason Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Jaegeuk Kim Cc: Steven Whitehouse Cc: Dave Kleikamp Cc: Joern Engel Cc: Prasad Joshi Cc: Trond Myklebust Cc: KONISHI Ryusuke Cc: Mark Fasheh Cc: Joel Becker Cc: Ben Myers Cc: xfs@oss.sgi.com Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Len Brown Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Herton Ronaldo Krzesinski Cc: Ben Hutchings Cc: Andrew Morton Cc: Guo Chao Cc: Tejun Heo Cc: Asai Thambi S P Cc: Selvan Mani Cc: Sam Bradshaw Cc: Wei Yongjun Cc: "Roger Pau Monné" Cc: Jan Beulich Cc: Stefano Stabellini Cc: Ian Campbell Cc: Sebastian Ott Cc: Christian Borntraeger Cc: Minchan Kim Cc: Jiang Liu Cc: Nitin Gupta Cc: Jerome Marchand Cc: Joe Perches Cc: Peng Tao Cc: Andy Adamson Cc: fanchaoting Cc: Jie Liu Cc: Sunil Mushran Cc: "Martin K. Petersen" Cc: Namjae Jeon Cc: Pankaj Kumar Cc: Dan Magenheimer Cc: Mel Gorman 6

direct-io: Use return from cmpxchg to decide of assignment happened

2013-09-09T17:47:42Z

Not using the return value can in the generic case be racy, so it's in general good practice to check the return value instead. This also resolved the warning caused on ARM and other architectures: fs/direct-io.c: In function 'sb_init_dio_done_wq': fs/direct-io.c:557:2: warning: value computed is not used [-Wunused-value] Signed-off-by: Olof Johansson Reviewed-by: Jan Kara Cc: Geert Uytterhoeven Cc: Stephen Rothwell Cc: Al Viro Cc: Christoph Hellwig Cc: Russell King Cc: H Peter Anvin Signed-off-by: Linus Torvalds

direct-io: Handle O_(D)SYNC AIO

2013-09-04T13:23:46Z

Call generic_write_sync() from the deferred I/O completion handler if O_DSYNC is set for a write request. Also make sure various callers don't call generic_write_sync if the direct I/O code returns -EIOCBQUEUED. Based on an earlier patch from Jan Kara with updates from Jeff Moyer and Darrick J. Wong . Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro

direct-io: Implement generic deferred AIO completions

2013-09-04T13:23:46Z

Add support to the core direct-io code to defer AIO completions to user context using a workqueue. This replaces opencoded and less efficient code in XFS and ext4 (we save a memory allocation for each direct IO) and will be needed to properly support O_(D)SYNC for AIO. The communication between the filesystem and the direct I/O code requires a new buffer head flag, which is a bit ugly but not avoidable until the direct I/O code stops abusing the buffer_head structure for communicating with the filesystems. Currently this creates a per-superblock unbound workqueue for these completions, which is taken from an earlier patch by Jan Kara. I'm not really convinced about this use and would prefer a "normal" global workqueue with a high concurrency limit, but this needs further discussion. JK: Fixed ext4 part, dynamic allocation of the workqueue. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro

Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-block

2013-05-08T17:13:35Z

Pull block core updates from Jens Axboe: - Major bit is Kents prep work for immutable bio vecs. - Stable candidate fix for a scheduling-while-atomic in the queue bypass operation. - Fix for the hang on exceeded rq->datalen 32-bit unsigned when merging discard bios. - Tejuns changes to convert the writeback thread pool to the generic workqueue mechanism. - Runtime PM framework, SCSI patches exists on top of these in James' tree. - A few random fixes. * 'for-3.10/core' of git://git.kernel.dk/linux-block: (40 commits) relay: move remove_buf_file inside relay_close_buf partitions/efi.c: replace useless kzalloc's by kmalloc's fs/block_dev.c: fix iov_shorten() criteria in blkdev_aio_read() block: fix max discard sectors limit blkcg: fix "scheduling while atomic" in blk_queue_bypass_start Documentation: cfq-iosched: update documentation help for cfq tunables writeback: expose the bdi_wq workqueue writeback: replace custom worker pool implementation with unbound workqueue writeback: remove unused bdi_pending_list aoe: Fix unitialized var usage bio-integrity: Add explicit field for owner of bip_buf block: Add an explicit bio flag for bios that own their bvec block: Add bio_alloc_pages() block: Convert some code to bio_for_each_segment_all() block: Add bio_for_each_segment_all() bounce: Refactor __blk_queue_bounce to not use bi_io_vec raid1: use bio_copy_data() pktcdvd: Use bio_reset() in disabled code to kill bi_idx usage pktcdvd: use bio_copy_data() block: Add bio_copy_data() ...

aio: don't include aio.h in sched.h

2013-05-08T03:16:25Z

Faster kernel compiles by way of fewer unnecessary includes. [akpm@linux-foundation.org: fix fallout] [akpm@linux-foundation.org: fix build] Signed-off-by: Kent Overstreet Cc: Zach Brown Cc: Felipe Balbi Cc: Greg Kroah-Hartman Cc: Mark Fasheh Cc: Joel Becker Cc: Rusty Russell Cc: Jens Axboe Cc: Asai Thambi S P Cc: Selvan Mani Cc: Sam Bradshaw Cc: Jeff Moyer Cc: Al Viro Cc: Benjamin LaHaise Reviewed-by: "Theodore Ts'o" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

direct-io: submit bio after boundary buffer is added to it

2013-04-29T22:54:29Z

Currently, dio_send_cur_page() submits bio before current page and cached sdio->cur_page is added to the bio if sdio->boundary is set. This is actually wrong because sdio->boundary means the current buffer is the last one before metadata needs to be read. So we should rather submit the bio after the current page is added to it. Signed-off-by: Jan Kara Reported-by: Kazuya Mio Tested-by: Kazuya Mio Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

direct-io: fix boundary block handling

2013-04-29T22:54:28Z

When we read/write a file sequentially, we will read/write not only the data blocks but also the indirect blocks that may not be physically adjacent to the data blocks. So filesystems set the BH_Boundary flag to submit the previous I/O before reading/writing an indirect block. However the generic direct IO code mishandles buffer_boundary(), setting sdio->boundary before each submit_page_section() call which results in sending only one page bios as underlying code thinks this page is the last in the contiguous extent. So fix the problem by setting sdio->boundary only if the current page is really the last one in the mapped extent. With this patch and "direct-io: submit bio after boundary buffer is added to it" I've measured about 10% throughput improvement of direct IO reads on ext3 with SATA harddrive (from 90 MB/s to 100 MB/s). With ramdisk, the improvement was about 3-fold (from 350 MB/s to 1.2 GB/s). For other filesystems (such as ext4), the improvements won't be as visible because the frequency of BH_Boundary flag being set is much smaller. Signed-off-by: Jan Kara Reported-by: Kazuya Mio Tested-by: Kazuya Mio Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

block: Convert some code to bio_for_each_segment_all()

2013-03-23T21:26:30Z

More prep work for immutable bvecs: A few places in the code were either open coding or using the wrong version - fix. After we introduce the bvec iter, it'll no longer be possible to modify the biovec through bio_for_each_segment_all() - it doesn't increment a pointer to the current bvec, you pass in a struct bio_vec (not a pointer) which is updated with what the current biovec would be (taking into account bi_bvec_done and bi_size). So because of that it's more worthwhile to be consistent about bio_for_each_segment()/bio_for_each_segment_all() usage. Signed-off-by: Kent Overstreet CC: Jens Axboe CC: NeilBrown CC: Alasdair Kergon CC: dm-devel@redhat.com CC: Alexander Viro

fs: Fix possible use-after-free with AIO

2013-02-23T04:31:36Z

Running AIO is pinning inode in memory using file reference. Once AIO is completed using aio_complete(), file reference is put and inode can be freed from memory. So we have to be sure that calling aio_complete() is the last thing we do with the inode. CC: Christoph Hellwig CC: Jens Axboe CC: Jeff Moyer CC: stable@vger.kernel.org Acked-by: Jeff Moyer Signed-off-by: Jan Kara Signed-off-by: Al Viro