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2013-01-14vfs: add missing virtual cache flush after editing partial pagesLinus Torvalds
Andrew Morton pointed this out a month ago, and then I completely forgot about it. If we read a partial last page of a block device, we will zero out the end of the page, but since that page can then be mapped into user space, we should also make sure to flush the cache on architectures that have virtual caches. We have the flush_dcache_page() function for this, so use it. Now, in practice this really never matters, because nobody sane uses virtual caches to begin with, and they largely exist on old broken RISC arhitectures. And even if you did run on one of those obsolete CPU's, the whole "mmap and access the last partial page of a block device" behavior probably doesn't actually exist. The normal IO functions (read/write) will never see the zeroed-out part of the page that migth not be coherent in the cache, because they honor the size of the device. So I'm marking this for stable (3.7 only), but I'm not sure anybody will ever care. Pointed-out-by: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org # 3.7 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12fs/buffer.c: remove redundant initialization in alloc_page_buffers()Yan Hong
buffer_head comes from kmem_cache_zalloc(), no need to zero its fields. Signed-off-by: Yan Hong <clouds.yan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12fs/buffer.c: do not inline exported functionYan Hong
It makes no sense to inline an exported function. Signed-off-by: Yan Hong <clouds.yan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11mm: redefine address_space.assoc_mappingRafael Aquini
Overhaul struct address_space.assoc_mapping renaming it to address_space.private_data and its type is redefined to void*. By this approach we consistently name the .private_* elements from struct address_space as well as allow extended usage for address_space association with other data structures through ->private_data. Also, all users of old ->assoc_mapping element are converted to reflect its new name and type change (->private_data). Signed-off-by: Rafael Aquini <aquini@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Andi Kleen <andi@firstfloor.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-05vfs: clear to the end of the buffer on partial buffer readsDan Carpenter
READ is zero so the "rw & READ" test is always false. The intended test was "((rw & RW_MASK) == READ)". Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-04vfs: avoid "attempt to access beyond end of device" warningsLinus Torvalds
The block device access simplification that avoided accessing the (racy) block size information (commit bbec0270bdd8: "blkdev_max_block: make private to fs/buffer.c") no longer checks the maximum block size in the block mapping path. That was _almost_ as simple as just removing the code entirely, because the readers and writers all check the size of the device anyway, so under normal circumstances it "just worked". However, the block size may be such that the end of the device may straddle one single buffer_head. At which point we may still want to access the end of the device, but the buffer we use to access it partially extends past the end. The 'bd_set_size()' function intentionally sets the block size to avoid this, but mounting the device - or setting the block size by hand to some other value - can modify that block size. So instead, teach 'submit_bh()' about the special case of the buffer head straddling the end of the device, and turning such an access into a smaller IO access, avoiding the problem. This, btw, also means that unlike before, we can now access the whole device regardless of device block size setting. So now, even if the device size is only 512-byte aligned, we can read and write even the last sector even when having a much bigger block size for accessing the rest of the device. So with this, we could now get rid of the 'bd_set_size()' block size code entirely - resulting in faster IO for the common case - but that would be a separate patch. Reported-and-tested-by: Romain Francoise <romain@orebokech.com> Reporeted-and-tested-by: Meelis Roos <mroos@linux.ee> Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-29blkdev_max_block: make private to fs/buffer.cLinus Torvalds
We really don't want to look at the block size for the raw block device accesses in fs/block-dev.c, because it may be changing from under us. So get rid of the max_block logic entirely, since the caller should already have done it anyway. That leaves the only user of this function in fs/buffer.c, so move the whole function there and make it static. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-29fs/buffer.c: make block-size be per-page and protected by the page lockLinus Torvalds
This makes the buffer size handling be a per-page thing, which allows us to not have to worry about locking too much when changing the buffer size. If a page doesn't have buffers, we still need to read the block size from the inode, but we can do that with ACCESS_ONCE(), so that even if the size is changing, we get a consistent value. This doesn't convert all functions - many of the buffer functions are used purely by filesystems, which in turn results in the buffer size being fixed at mount-time. So they don't have the same consistency issues that the raw device access can have. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The big new feature added this time is supporting online resizing using the meta_bg feature. This allows us to resize file systems which are greater than 16TB. In addition, the speed of online resizing has been improved in general. We also fix a number of races, some of which could lead to deadlocks, in ext4's Asynchronous I/O and online defrag support, thanks to good work by Dmitry Monakhov. There are also a large number of more minor bug fixes and cleanups from a number of other ext4 contributors, quite of few of which have submitted fixes for the first time." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (69 commits) ext4: fix ext4_flush_completed_IO wait semantics ext4: fix mtime update in nodelalloc mode ext4: fix ext_remove_space for punch_hole case ext4: punch_hole should wait for DIO writers ext4: serialize truncate with owerwrite DIO workers ext4: endless truncate due to nonlocked dio readers ext4: serialize unlocked dio reads with truncate ext4: serialize dio nonlocked reads with defrag workers ext4: completed_io locking cleanup ext4: fix unwritten counter leakage ext4: give i_aiodio_unwritten a more appropriate name ext4: ext4_inode_info diet ext4: convert to use leXX_add_cpu() ext4: ext4_bread usage audit fs: reserve fallocate flag codepoint ext4: remove redundant offset check in mext_check_arguments() ext4: don't clear orphan list on ro mount with errors jbd2: fix assertion failure in commit code due to lacking transaction credits ext4: release donor reference when EXT4_IOC_MOVE_EXT ioctl fails ext4: enable FITRIM ioctl on bigalloc file system ...
2012-09-30ext4: fix mtime update in nodelalloc modeTheodore Ts'o
Commits 5e8830dc85d0 and 41c4d25f78c0 introduced a regression into v3.6-rc1 for ext4 in nodealloc mode, such that mtime updates would not take place for files modified via mmap if the page was already in the page cache. This would also affect ext3 file systems mounted using the ext4 file system driver. The problem was that ext4_page_mkwrite() had a shortcut which would avoid calling __block_page_mkwrite() under some circumstances, and the above two commit transferred the responsibility of calling file_update_time() to __block_page_mkwrite --- which woudln't get called in some circumstances. Since __block_page_mkwrite() only has three callers, block_page_mkwrite(), ext4_page_mkwrite, and nilfs_page_mkwrite(), the best way to solve this is to move the responsibility for calling file_update_time() to its caller. This problem was found via xfstests #215 with a file system mounted with -o nodelalloc. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: stable@vger.kernel.org
2012-08-23block: replace __getblk_slow misfix by grow_dev_page fixHugh Dickins
Commit 91f68c89d8f3 ("block: fix infinite loop in __getblk_slow") is not good: a successful call to grow_buffers() cannot guarantee that the page won't be reclaimed before the immediate next call to __find_get_block(), which is why there was always a loop there. Yesterday I got "EXT4-fs error (device loop0): __ext4_get_inode_loc:3595: inode #19278: block 664: comm cc1: unable to read itable block" on console, which pointed to this commit. I've been trying to bisect for weeks, why kbuild-on-ext4-on-loop-on-tmpfs sometimes fails from a missing header file, under memory pressure on ppc G5. I've never seen this on x86, and I've never seen it on 3.5-rc7 itself, despite that commit being in there: bisection pointed to an irrelevant pinctrl merge, but hard to tell when failure takes between 18 minutes and 38 hours (but so far it's happened quicker on 3.6-rc2). (I've since found such __ext4_get_inode_loc errors in /var/log/messages from previous weeks: why the message never appeared on console until yesterday morning is a mystery for another day.) Revert 91f68c89d8f3, restoring __getblk_slow() to how it was (plus a checkpatch nitfix). Simplify the interface between grow_buffers() and grow_dev_page(), and avoid the infinite loop beyond end of device by instead checking init_page_buffers()'s end_block there (I presume that's more efficient than a repeated call to blkdev_max_block()), returning -ENXIO to __getblk_slow() in that case. And remove akpm's ten-year-old "__getblk() cannot fail ... weird" comment, but that is worrying: are all users of __getblk() really now prepared for a NULL bh beyond end of device, or will some oops?? Signed-off-by: Hugh Dickins <hughd@google.com> Cc: stable@vger.kernel.org # 3.0 3.2 3.4 3.5 Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-07-31fs: Protect write paths by sb_start_write - sb_end_writeJan Kara
There are several entry points which dirty pages in a filesystem. mmap (handled by block_page_mkwrite()), buffered write (handled by __generic_file_aio_write()), splice write (generic_file_splice_write), truncate, and fallocate (these can dirty last partial page - handled inside each filesystem separately). Protect these places with sb_start_write() and sb_end_write(). ->page_mkwrite() calls are particularly complex since they are called with mmap_sem held and thus we cannot use standard sb_start_write() due to lock ordering constraints. We solve the problem by using a special freeze protection sb_start_pagefault() which ranks below mmap_sem. BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31fs: Push file_update_time() into __block_page_mkwrite()Jan Kara
Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-13block: fix infinite loop in __getblk_slowJeff Moyer
Commit 080399aaaf35 ("block: don't mark buffers beyond end of disk as mapped") exposed a bug in __getblk_slow that causes mount to hang as it loops infinitely waiting for a buffer that lies beyond the end of the disk to become uptodate. The problem was initially reported by Torsten Hilbrich here: https://lkml.org/lkml/2012/6/18/54 and also reported independently here: http://www.sysresccd.org/forums/viewtopic.php?f=13&t=4511 and then Richard W.M. Jones and Marcos Mello noted a few separate bugzillas also associated with the same issue. This patch has been confirmed to fix: https://bugzilla.redhat.com/show_bug.cgi?id=835019 The main problem is here, in __getblk_slow: for (;;) { struct buffer_head * bh; int ret; bh = __find_get_block(bdev, block, size); if (bh) return bh; ret = grow_buffers(bdev, block, size); if (ret < 0) return NULL; if (ret == 0) free_more_memory(); } __find_get_block does not find the block, since it will not be marked as mapped, and so grow_buffers is called to fill in the buffers for the associated page. I believe the for (;;) loop is there primarily to retry in the case of memory pressure keeping grow_buffers from succeeding. However, we also continue to loop for other cases, like the block lying beond the end of the disk. So, the fix I came up with is to only loop when grow_buffers fails due to memory allocation issues (return value of 0). The attached patch was tested by myself, Torsten, and Rich, and was found to resolve the problem in call cases. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Reported-and-Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Tested-by: Richard W.M. Jones <rjones@redhat.com> Reviewed-by: Josh Boyer <jwboyer@redhat.com> Cc: Stable <stable@vger.kernel.org> # 3.0+ [ Jens is on vacation, taking this directly - Linus ] -- Stable Notes: this patch requires backport to 3.0, 3.2 and 3.3. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30fs: Move bh_cachep to the __read_mostly sectionShai Fultheim
bh_cachep is only written to once on initialization, so move it to the __read_mostly section. Signed-off-by: Shai Fultheim <shai@scalemp.com> Signed-off-by: Vlad Zolotarov <vlad@scalemp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-11block: don't mark buffers beyond end of disk as mappedJeff Moyer
Hi, We have a bug report open where a squashfs image mounted on ppc64 would exhibit errors due to trying to read beyond the end of the disk. It can easily be reproduced by doing the following: [root@ibm-p750e-02-lp3 ~]# ls -l install.img -rw-r--r-- 1 root root 142032896 Apr 30 16:46 install.img [root@ibm-p750e-02-lp3 ~]# mount -o loop ./install.img /mnt/test [root@ibm-p750e-02-lp3 ~]# dd if=/dev/loop0 of=/dev/null dd: reading `/dev/loop0': Input/output error 277376+0 records in 277376+0 records out 142016512 bytes (142 MB) copied, 0.9465 s, 150 MB/s In dmesg, you'll find the following: squashfs: version 4.0 (2009/01/31) Phillip Lougher [ 43.106012] attempt to access beyond end of device [ 43.106029] loop0: rw=0, want=277410, limit=277408 [ 43.106039] Buffer I/O error on device loop0, logical block 138704 [ 43.106053] attempt to access beyond end of device [ 43.106057] loop0: rw=0, want=277412, limit=277408 [ 43.106061] Buffer I/O error on device loop0, logical block 138705 [ 43.106066] attempt to access beyond end of device [ 43.106070] loop0: rw=0, want=277414, limit=277408 [ 43.106073] Buffer I/O error on device loop0, logical block 138706 [ 43.106078] attempt to access beyond end of device [ 43.106081] loop0: rw=0, want=277416, limit=277408 [ 43.106085] Buffer I/O error on device loop0, logical block 138707 [ 43.106089] attempt to access beyond end of device [ 43.106093] loop0: rw=0, want=277418, limit=277408 [ 43.106096] Buffer I/O error on device loop0, logical block 138708 [ 43.106101] attempt to access beyond end of device [ 43.106104] loop0: rw=0, want=277420, limit=277408 [ 43.106108] Buffer I/O error on device loop0, logical block 138709 [ 43.106112] attempt to access beyond end of device [ 43.106116] loop0: rw=0, want=277422, limit=277408 [ 43.106120] Buffer I/O error on device loop0, logical block 138710 [ 43.106124] attempt to access beyond end of device [ 43.106128] loop0: rw=0, want=277424, limit=277408 [ 43.106131] Buffer I/O error on device loop0, logical block 138711 [ 43.106135] attempt to access beyond end of device [ 43.106139] loop0: rw=0, want=277426, limit=277408 [ 43.106143] Buffer I/O error on device loop0, logical block 138712 [ 43.106147] attempt to access beyond end of device [ 43.106151] loop0: rw=0, want=277428, limit=277408 [ 43.106154] Buffer I/O error on device loop0, logical block 138713 [ 43.106158] attempt to access beyond end of device [ 43.106162] loop0: rw=0, want=277430, limit=277408 [ 43.106166] attempt to access beyond end of device [ 43.106169] loop0: rw=0, want=277432, limit=277408 ... [ 43.106307] attempt to access beyond end of device [ 43.106311] loop0: rw=0, want=277470, limit=2774 Squashfs manages to read in the end block(s) of the disk during the mount operation. Then, when dd reads the block device, it leads to block_read_full_page being called with buffers that are beyond end of disk, but are marked as mapped. Thus, it would end up submitting read I/O against them, resulting in the errors mentioned above. I fixed the problem by modifying init_page_buffers to only set the buffer mapped if it fell inside of i_size. Cheers, Jeff Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Nick Piggin <npiggin@kernel.dk> -- Changes from v1->v2: re-used max_block, as suggested by Nick Piggin. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-25fs/buffer.c: remove BUG() in possible but rare conditionGlauber Costa
While stressing the kernel with with failing allocations today, I hit the following chain of events: alloc_page_buffers(): bh = alloc_buffer_head(GFP_NOFS); if (!bh) goto no_grow; <= path taken grow_dev_page(): bh = alloc_page_buffers(page, size, 0); if (!bh) goto failed; <= taken, consequence of the above and then the failed path BUG()s the kernel. The failure is inserted a litte bit artificially, but even then, I see no reason why it should be deemed impossible in a real box. Even though this is not a condition that we expect to see around every time, failed allocations are expected to be handled, and BUG() sounds just too much. As a matter of fact, grow_dev_page() can return NULL just fine in other circumstances, so I propose we just remove it, then. Signed-off-by: Glauber Costa <glommer@parallels.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>
2012-03-28fs: only send IPI to invalidate LRU BH when neededGilad Ben-Yossef
In several code paths, such as when unmounting a file system (but not only) we send an IPI to ask each cpu to invalidate its local LRU BHs. For multi-cores systems that have many cpus that may not have any LRU BH because they are idle or because they have not performed any file system accesses since last invalidation (e.g. CPU crunching on high perfomance computing nodes that write results to shared memory or only using filesystems that do not use the bh layer.) This can lead to loss of performance each time someone switches the KVM (the virtual keyboard and screen type, not the hypervisor) if it has a USB storage stuck in. This patch attempts to only send an IPI to cpus that have LRU BH. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-28fs: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-01-03fs: move code out of buffer.cAl Viro
Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export kill_bdev as well, so brd doesn't have to open code it. Reduce buffer_head.h requirement accordingly. Removed a rather large comment from invalidate_bdev, as it looked a bit obsolete to bother moving. The small comment replacing it says enough. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-11-06Merge branch 'writeback-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Add a 'reason' to wb_writeback_work writeback: send work item to queue_io, move_expired_inodes writeback: trace event balance_dirty_pages writeback: trace event bdi_dirty_ratelimit writeback: fix ppc compile warnings on do_div(long long, unsigned long) writeback: per-bdi background threshold writeback: dirty position control - bdi reserve area writeback: control dirty pause time writeback: limit max dirty pause time writeback: IO-less balance_dirty_pages() writeback: per task dirty rate limit writeback: stabilize bdi->dirty_ratelimit writeback: dirty rate control writeback: add bg_threshold parameter to __bdi_update_bandwidth() writeback: dirty position control writeback: account per-bdi accumulated dirtied pages
2011-10-31fs/buffer.c: add device information for error output in __find_get_block_slow()Tao Ma
On the ext4 mailing list[1], we got some report about errors in __find_get_block_slow(), but the information is very limited. If the device information is given, we can know the name of the sick volume. Futhermore, we can get the corresponding status of that block(group, inode block etc) by analyzing the disk layout. [1] http://marc.info/?l=linux-ext4&m=131379831421147&w=2 Signed-off-by: Tao Ma <boyu.mt@taobao.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31writeback: Add a 'reason' to wb_writeback_workCurt Wohlgemuth
This creates a new 'reason' field in a wb_writeback_work structure, which unambiguously identifies who initiates writeback activity. A 'wb_reason' enumeration has been added to writeback.h, to enumerate the possible reasons. The 'writeback_work_class' and tracepoint event class and 'writeback_queue_io' tracepoints are updated to include the symbolic 'reason' in all trace events. And the 'writeback_inodes_sbXXX' family of routines has had a wb_stats parameter added to them, so callers can specify why writeback is being started. Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-28cleanup: vfs: small comment fix for block_invalidatepageWang Sheng-Hui
The patch is aganist 3.1-rc3. Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-06-16vfs: Fix data corruption after failed write in __block_write_begin()Jan Kara
I've got a report of a file corruption from fsxlinux on ext3. The important operations to the page were: mapwrite to a hole partial write to the page read - found the page zeroed from the end of the normal write The culprit seems to be that if get_block() fails in __block_write_begin() (e.g. transient ENOSPC in ext3), the function does ClearPageUptodate(page). Thus when we retry the write, the logic in __block_write_begin() thinks zeroing of the page is needed and overwrites old data. In fact, I don't see why we should ever need to zero the uptodate bit here - either the page was uptodate when we entered __block_write_begin() and it should stay so when we leave it, or it was not uptodate and noone had right to set it uptodate during __block_write_begin() so it remains !uptodate when we leave as well. So just remove clearing of the bit. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-28fs: block_page_mkwrite should wait for writeback to finishDarrick J. Wong
For filesystems such as nilfs2 and xfs that use block_page_mkwrite, modify that function to wait for pending writeback before allowing the page to become writable. This is needed to stabilize pages during writeback for those two filesystems. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem: xen: cleancache shim to Xen Transcendent Memory ocfs2: add cleancache support ext4: add cleancache support btrfs: add cleancache support ext3: add cleancache support mm/fs: add hooks to support cleancache mm: cleancache core ops functions and config fs: add field to superblock to support cleancache mm/fs: cleancache documentation Fix up trivial conflict in fs/btrfs/extent_io.c due to includes
2011-05-26mm/fs: add hooks to support cleancacheDan Magenheimer
This fourth patch of eight in this cleancache series provides the core hooks in VFS for: initializing cleancache per filesystem; capturing clean pages reclaimed by page cache; attempting to get pages from cleancache before filesystem read; and ensuring coherency between pagecache, disk, and cleancache. Note that the placement of these hooks was stable from 2.6.18 to 2.6.38; a minor semantic change was required due to a patchset in 2.6.39. All hooks become no-ops if CONFIG_CLEANCACHE is unset, or become a check of a boolean global if CONFIG_CLEANCACHE is set but no cleancache "backend" has claimed cleancache_ops. Details and a FAQ can be found in Documentation/vm/cleancache.txt [v8: minchan.kim@gmail.com: adapt to new remove_from_page_cache function] Signed-off-by: Chris Mason <chris.mason@oracle.com> Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com> Reviewed-by: Jeremy Fitzhardinge <jeremy@goop.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik Van Riel <riel@redhat.com> Cc: Jan Beulich <JBeulich@novell.com> Cc: Andreas Dilger <adilger@sun.com> Cc: Ted Ts'o <tytso@mit.edu> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <joel.becker@oracle.com> Cc: Nitin Gupta <ngupta@vflare.org>
2011-05-26vfs: Block mmapped writes while the fs is frozenJan Kara
We should not allow file modification via mmap while the filesystem is frozen. So block in block_page_mkwrite() while the filesystem is frozen. We cannot do the blocking wait in __block_page_mkwrite() since e.g. ext4 will want to call that function with transaction started in some cases and that would deadlock. But we can at least do the non-blocking reliable check in __block_page_mkwrite() which is the hardest part anyway. We have to check for frozen filesystem with the page marked dirty and under page lock with which we then return from ->page_mkwrite(). Only that way we cannot race with writeback done by freezing code - either we mark the page dirty after the writeback has started, see freezing in progress and block, or writeback will wait for our page lock which is released only when the fault is done and then writeback will writeout and writeprotect the page again. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26vfs: Create __block_page_mkwrite() helper passing error values backJan Kara
Create __block_page_mkwrite() helper which does all what block_page_mkwrite() does except that it passes back errors from __block_write_begin / block_commit_write calls. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-24Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: fs: simplify iget & friends fs: pull inode->i_lock up out of writeback_single_inode fs: rename inode_lock to inode_hash_lock fs: move i_wb_list out from under inode_lock fs: move i_sb_list out from under inode_lock fs: remove inode_lock from iput_final and prune_icache fs: Lock the inode LRU list separately fs: factor inode disposal fs: protect inode->i_state with inode->i_lock autofs4: Do not potentially dereference NULL pointer returned by fget() in autofs_dev_ioctl_setpipefd() autofs4 - remove autofs4_lock autofs4 - fix d_manage() return on rcu-walk autofs4 - fix autofs4_expire_indirect() traversal autofs4 - fix dentry leak in autofs4_expire_direct() autofs4 - reinstate last used update on access vfs - check non-mountpoint dentry might block in __follow_mount_rcu()
2011-03-24fs: protect inode->i_state with inode->i_lockDave Chinner
Protect inode state transitions and validity checks with the inode->i_lock. This enables us to make inode state transitions independently of the inode_lock and is the first step to peeling away the inode_lock from the code. This requires that __iget() is done atomically with i_state checks during list traversals so that we don't race with another thread marking the inode I_FREEING between the state check and grabbing the reference. Also remove the unlock_new_inode() memory barrier optimisation required to avoid taking the inode_lock when clearing I_NEW. Simplify the code by simply taking the inode->i_lock around the state change and wakeup. Because the wakeup is no longer tricky, remove the wake_up_inode() function and open code the wakeup where necessary. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-17fs: make fsync_buffers_list() plugJens Axboe
It used WRITE_SYNC_PLUG before and potentially submits a batch of IO, so lets enable plugging for this case. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10block: kill off REQ_UNPLUGJens Axboe
With the plugging now being explicitly controlled by the submitter, callers need not pass down unplugging hints to the block layer. If they want to unplug, it's because they manually plugged on their own - in which case, they should just unplug at will. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10block: remove per-queue pluggingJens Axboe
Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-17fs: Use this_cpu_inc_return in buffer.cChristoph Lameter
__this_cpu_inc can create a single instruction with the same effect as the _get_cpu_var(..)++ construct in buffer.c. Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Christoph Hellwig <hch@lst.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2010-12-17fs: Use this_cpu_xx operations in buffer.cChristoph Lameter
Optimize various per cpu area operations through these new percpu operations. These operations avoid address calculations through the use of segment prefixes and multiple memory references through RMW instructions etc. Reduces code size: Before: christoph@linux-2.6$ size fs/buffer.o text data bss dec hex filename 19169 80 28 19277 4b4d fs/buffer.o After: christoph@linux-2.6$ size fs/buffer.o text data bss dec hex filename 19138 80 28 19246 4b2e fs/buffer.o V3->V4: - Move the use of this_cpu_inc_return into a later patch so that this one can go in without percpu infrastructure changes. Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Christoph Hellwig <hch@lst.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2010-10-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits) split invalidate_inodes() fs: skip I_FREEING inodes in writeback_sb_inodes fs: fold invalidate_list into invalidate_inodes fs: do not drop inode_lock in dispose_list fs: inode split IO and LRU lists fs: switch bdev inode bdi's correctly fs: fix buffer invalidation in invalidate_list fsnotify: use dget_parent smbfs: use dget_parent exportfs: use dget_parent fs: use RCU read side protection in d_validate fs: clean up dentry lru modification fs: split __shrink_dcache_sb fs: improve DCACHE_REFERENCED usage fs: use percpu counter for nr_dentry and nr_dentry_unused fs: simplify __d_free fs: take dcache_lock inside __d_path fs: do not assign default i_ino in new_inode fs: introduce a per-cpu last_ino allocator new helper: ihold() ...
2010-10-26fs/buffer.c: remove duplicated assignment to b_privateNamhyung Kim
bh->b_private is initialized within init_buffer(), thus this assignment is redundant. Signed-off-by: Namhyung Kim <namhyung@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>
2010-10-26writeback: remove nonblocking/encountered_congestion referencesWu Fengguang
This removes more dead code that was somehow missed by commit 0d99519efef (writeback: remove unused nonblocking and congestion checks). There are no behavior change except for the removal of two entries from one of the ext4 tracing interface. The nonblocking checks in ->writepages are no longer used because the flusher now prefer to block on get_request_wait() than to skip inodes on IO congestion. The latter will lead to more seeky IO. The nonblocking checks in ->writepage are no longer used because it's redundant with the WB_SYNC_NONE check. We no long set ->nonblocking in VM page out and page migration, because a) it's effectively redundant with WB_SYNC_NONE in current code b) it's old semantic of "Don't get stuck on request queues" is mis-behavior: that would skip some dirty inodes on congestion and page out others, which is unfair in terms of LRU age. Inspired by Christoph Hellwig. Thanks! Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: David Howells <dhowells@redhat.com> Cc: Sage Weil <sage@newdream.net> Cc: Steve French <sfrench@samba.org> Cc: Chris Mason <chris.mason@oracle.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-25fs/buffer.c: call __block_write_begin() if we have pageNamhyung Kim
If we have the appropriate page already, call __block_write_begin() directly instead of releasing and regrabbing it inside of block_write_begin(). Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs/buffer.c: remove duplicated assignment on b_privateNamhyung Kim
bh->b_private is initialized within init_buffer(), thus the assignment should be redundant. Remove it. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: kill block_prepare_writeChristoph Hellwig
__block_write_begin and block_prepare_write are identical except for slightly different calling conventions. Convert all callers to the __block_write_begin calling conventions and drop block_prepare_write. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-09-10block: remove the BH_Eopnotsupp flagChristoph Hellwig
This flag was only set for barrier buffers, which we don't submit anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-18remove SWRITE* I/O typesChristoph Hellwig
These flags aren't real I/O types, but tell ll_rw_block to always lock the buffer instead of giving up on a failed trylock. Instead add a new write_dirty_buffer helper that implements this semantic and use it from the existing SWRITE* callers. Note that the ll_rw_block code had a bug where it didn't promote WRITE_SYNC_PLUG properly, which this patch fixes. In the ufs code clean up the helper that used to call ll_rw_block to mirror sync_dirty_buffer, which is the function it implements for compound buffers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-18kill BH_Ordered flagChristoph Hellwig
Instead of abusing a buffer_head flag just add a variant of sync_dirty_buffer which allows passing the exact type of write flag required. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09get rid of block_write_begin_newtruncChristoph Hellwig
Move the call to vmtruncate to get rid of accessive blocks to the callers in preparation of the new truncate sequence and rename the non-truncating version to block_write_begin. While we're at it also remove several unused arguments to block_write_begin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09introduce __block_write_beginChristoph Hellwig
Split up the block_write_begin implementation - __block_write_begin is a new trivial wrapper for block_prepare_write that always takes an already allocated page and can be either called from block_write_begin or filesystem code that already has a page allocated. Remove the handling of already allocated pages from block_write_begin after switching all callers that do it to __block_write_begin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09get rid of cont_write_begin_newtruncChristoph Hellwig
Move the call to vmtruncate to get rid of accessive blocks to the callers in preparation of the new truncate sequence and rename the non-truncating version to cont_write_begin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09get rid of nobh_write_begin_newtruncChristoph Hellwig
Move the call to vmtruncate to get rid of accessive blocks to the only remaining caller and rename the non-truncating version to nobh_write_begin. Get rid of the superflous file argument to it while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>