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* smp: add func to IPI cpus based on parameter funcGilad Ben-Yossef2012-03-292-0/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the on_each_cpu_cond() function that wraps on_each_cpu_mask() and calculates the cpumask of cpus to IPI by calling a function supplied as a parameter in order to determine whether to IPI each specific cpu. The function works around allocation failure of cpumask variable in CONFIG_CPUMASK_OFFSTACK=y by itereating over cpus sending an IPI a time via smp_call_function_single(). The function is useful since it allows to seperate the specific code that decided in each case whether to IPI a specific cpu for a specific request from the common boilerplate code of handling creating the mask, handling failures etc. [akpm@linux-foundation.org: s/gfpflags/gfp_flags/] [akpm@linux-foundation.org: avoid double-evaluation of `info' (per Michal), parenthesise evaluation of `cond_func'] [akpm@linux-foundation.org: s/CPU/CPUs, use all 80 cols in comment] Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux-foundation.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Pekka Enberg <penberg@kernel.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Sasha Levin <levinsasha928@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Avi Kivity <avi@redhat.com> Acked-by: Michal Nazarewicz <mina86@mina86.org> Cc: Kosaki Motohiro <kosaki.motohiro@gmail.com> Cc: Milton Miller <miltonm@bga.com> Reviewed-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* smp: introduce a generic on_each_cpu_mask() functionGilad Ben-Yossef2012-03-295-41/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have lots of infrastructure in place to partition multi-core systems such that we have a group of CPUs that are dedicated to specific task: cgroups, scheduler and interrupt affinity, and cpuisol= boot parameter. Still, kernel code will at times interrupt all CPUs in the system via IPIs for various needs. These IPIs are useful and cannot be avoided altogether, but in certain cases it is possible to interrupt only specific CPUs that have useful work to do and not the entire system. This patch set, inspired by discussions with Peter Zijlstra and Frederic Weisbecker when testing the nohz task patch set, is a first stab at trying to explore doing this by locating the places where such global IPI calls are being made and turning the global IPI into an IPI for a specific group of CPUs. The purpose of the patch set is to get feedback if this is the right way to go for dealing with this issue and indeed, if the issue is even worth dealing with at all. Based on the feedback from this patch set I plan to offer further patches that address similar issue in other code paths. This patch creates an on_each_cpu_mask() and on_each_cpu_cond() infrastructure API (the former derived from existing arch specific versions in Tile and Arm) and uses them to turn several global IPI invocation to per CPU group invocations. Core kernel: on_each_cpu_mask() calls a function on processors specified by cpumask, which may or may not include the local processor. You must not call this function with disabled interrupts or from a hardware interrupt handler or from a bottom half handler. arch/arm: Note that the generic version is a little different then the Arm one: 1. It has the mask as first parameter 2. It calls the function on the calling CPU with interrupts disabled, but this should be OK since the function is called on the other CPUs with interrupts disabled anyway. arch/tile: The API is the same as the tile private one, but the generic version also calls the function on the with interrupts disabled in UP case This is OK since the function is called on the other CPUs with interrupts disabled. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Reviewed-by: Christoph Lameter <cl@linux.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Pekka Enberg <penberg@kernel.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Sasha Levin <levinsasha928@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Avi Kivity <avi@redhat.com> Acked-by: Michal Nazarewicz <mina86@mina86.org> Cc: Kosaki Motohiro <kosaki.motohiro@gmail.com> Cc: Milton Miller <miltonm@bga.com> Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* swapon: check validity of swap_flagsHugh Dickins2012-03-292-0/+6
| | | | | | | | | | | | | | | | Most system calls taking flags first check that the flags passed in are valid, and that helps userspace to detect when new flags are supported. But swapon never did so: start checking now, to help if we ever want to support more swap_flags in future. It's difficult to get stray bits set in an int, and swapon is not widely used, so this is most unlikely to break any userspace; but we can just revert if it turns out to do so. Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, coredump: fail allocations when coredumping instead of oom killingDavid Rientjes2012-03-291-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The size of coredump files is limited by RLIMIT_CORE, however, allocating large amounts of memory results in three negative consequences: - the coredumping process may be chosen for oom kill and quickly deplete all memory reserves in oom conditions preventing further progress from being made or tasks from exiting, - the coredumping process may cause other processes to be oom killed without fault of their own as the result of a SIGSEGV, for example, in the coredumping process, or - the coredumping process may result in a livelock while writing to the dump file if it needs memory to allocate while other threads are in the exit path waiting on the coredumper to complete. This is fixed by implying __GFP_NORETRY in the page allocator for coredumping processes when reclaim has failed so the allocations fail and the process continues to exit. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: thp: fix up pmd_trans_unstable() locationsAndrea Arcangeli2012-03-292-3/+6
| | | | | | | | | | | | | | | pmd_trans_unstable() should be called before pmd_offset_map() in the locations where the mmap_sem is held for reading. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mark Salter <msalter@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm for fs: add truncate_pagecache_range()Hugh Dickins2012-03-292-1/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Holepunching filesystems ext4 and xfs are using truncate_inode_pages_range but forgetting to unmap pages first (ocfs2 remembers). This is not really a bug, since races already require truncate_inode_page() to handle that case once the page is locked; but it can be very inefficient if the file being punched happens to be mapped into many vmas. Provide a drop-in replacement truncate_pagecache_range() which does the unmapping pass first, handling the awkward mismatch between arguments to truncate_inode_pages_range() and arguments to unmap_mapping_range(). Note that holepunching does not unmap privately COWed pages in the range: POSIX requires that we do so when truncating, but it's hard to justify, difficult to implement without an i_size cutoff, and no filesystem is attempting to implement it. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: Alex Elder <elder@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Chinner <david@fromorbit.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>
* procfs: fix /proc/statmKAMEZAWA Hiroyuki2012-03-291-1/+1
| | | | | | | | | | bda7bad62bc4 ("procfs: speed up /proc/pid/stat, statm") broke /proc/statm - 'text' is printed twice by mistake. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reported-by: Ulrich Drepper <drepper@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'writeback-fixes' of ↵Linus Torvalds2012-03-281-20/+2
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux Pull trivial writeback fixes from Wu Fengguang: "They've been tested in linux-next for 20 days actually." * tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Remove outdated comment fs: Remove bogus wait in write_inode_now()
| * writeback: Remove outdated commentJan Kara2012-03-211-18/+2
| | | | | | | | | | | | | | | | | | | | | | | | The comment is hopelessly outdated and misplaced. We no longer have 'bdi' part of writeback work, the comment about blockdev super is outdated, comment about throttling as well. Information about list handling is in more detail at queue_io(). So just move the bit about older_than_this to close to move_expired_inodes() and remove the rest. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
| * fs: Remove bogus wait in write_inode_now()Jan Kara2012-03-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | inode_sync_wait() in write_inode_now() is just bogus. That function waits for I_SYNC bit to be cleared but writeback_single_inode() clears the bit on return so the wait is effectivelly a nop unless someone else submits the inode for writeback again. All the waiting write_inode_now() needs is achieved by using WB_SYNC_ALL writeback mode. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* | Merge tag 'ext4_for_linus' of ↵Linus Torvalds2012-03-2830-1611/+1522
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates for 3.4 from Ted Ts'o: "Ext4 commits for 3.3 merge window; mostly cleanups and bug fixes The changes to export dirty_writeback_interval are from Artem's s_dirt cleanup patch series. The same is true of the change to remove the s_dirt helper functions which never got used by anyone in-tree. I've run these changes by Al Viro, and am carrying them so that Artem can more easily fix up the rest of the file systems during the next merge window. (Originally we had hopped to remove the use of s_dirt from ext4 during this merge window, but his patches had some bugs, so I ultimately ended dropping them from the ext4 tree.)" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (66 commits) vfs: remove unused superblock helpers mm: export dirty_writeback_interval ext4: remove useless s_dirt assignment ext4: write superblock only once on unmount ext4: do not mark superblock as dirty unnecessarily ext4: correct ext4_punch_hole return codes ext4: remove restrictive checks for EOFBLOCKS_FL ext4: always set then trimmed blocks count into len ext4: fix trimmed block count accunting ext4: fix start and len arguments handling in ext4_trim_fs() ext4: update s_free_{inodes,blocks}_count during online resize ext4: change some printk() calls to use ext4_msg() instead ext4: avoid output message interleaving in ext4_error_<foo>() ext4: remove trailing newlines from ext4_msg() and ext4_error() messages ext4: add no_printk argument validation, fix fallout ext4: remove redundant "EXT4-fs: " from uses of ext4_msg ext4: give more helpful error message in ext4_ext_rm_leaf() ext4: remove unused code from ext4_ext_map_blocks() ext4: rewrite punch hole to use ext4_ext_remove_space() jbd2: cleanup journal tail after transaction commit ...
| * | vfs: remove unused superblock helpersArtem Bityutskiy2012-03-221-13/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the 'sb_mark_dirty()', 'sb_mark_clean()' and 'sb_is_dirty()' helpers which are not used. I introduced them 2 years and the intention was to make all file-systems use them in order to be able to optimize 'sync_supers()'. However, Al Viro vetoed my patches at the end and asked me to push superblock management down to file-systems and get rid of the 's_dirt' flag completely, as well as kill 'sync_supers()' altogether. Thus, remove the helpers. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | mm: export dirty_writeback_intervalArtem Bityutskiy2012-03-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Export 'dirty_writeback_interval' to make it visible to file-systems. We are going to push superblock management down to file-systems and get rid of the 'sync_supers' kernel thread completly. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: remove useless s_dirt assignmentArtem Bityutskiy2012-03-221-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean-up ext4 a tiny bit by removing useless s_dirt assignment in 'ext4_fill_super()' because a bit later we anyway call 'ext4_setup_super()' which writes the superblock to the media unconditionally. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: write superblock only once on unmountArtem Bityutskiy2012-03-221-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | In some rather rare cases it is possible that ext4 may the superblock to the media twice. This patch makes sure this does not happen. This should speed up unmounting in those cases. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: do not mark superblock as dirty unnecessarilyArtem Bityutskiy2012-03-221-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a0375156ca1041574b5d47cc7e32f10b891151b0 cleaned up superblock dirtying handling, but missed one place. This patch does what was intended: if we have the journal, then we update the superblock through the journal rather than doing this directly. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: correct ext4_punch_hole return codesAllison Henderson2012-03-221-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | ext4_punch_hole returns -ENOTSUPP but it should be using -EOPNOTSUPP Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com> Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: remove restrictive checks for EOFBLOCKS_FLLukas Czerner2012-03-222-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are going to remove the EOFBLOCKS_FL flag in the future, so this is the first part of the removal. We can not remove it entirely just now, since the e2fsck is still checking for it and it might cause headache to some people. Instead, remove the restrictive checks now and the rest later, when the new e2fsck code is out and common enough. This is also needed because punch hole already breaks the EOFBLOCKS_FL semantics, so it might cause the some troubles. So simply remove it. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: always set then trimmed blocks count into lenLukas Czerner2012-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if the range to trim is too small, for example on 1K fs the request to trim the first block, then the 'range->len' is not set reporting wrong number of discarded block to the caller. Fix this by always setting the 'range->len' before we return. Note that when there is a failure (-EINVAL) caller can not depend on 'range->len' being set properly. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: fix trimmed block count accuntingLukas Czerner2012-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when there is not enough free blocks in the block group to discard (grp->bb_free < minlen) the 'trimmed' is bumped up anyway with the number of discarded blocks from the previous iteration. Fix this by bumping up 'trimmed' only if the ext4_trim_all_free() was actually run. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: fix start and len arguments handling in ext4_trim_fs()Lukas Czerner2012-03-221-27/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The overflow can happen when we are calling get_group_no_and_offset() which stores the group number in the ext4_grpblk_t type which is actually int. However when the blocknr is big enough the group number might be bigger than ext4_grpblk_t resulting in overflow. This will most likely happen with FITRIM default argument len = ULLONG_MAX. Fix this by using "end" variable instead of "start+len" as it is easier to get right and specifically check that the end is not beyond the end of the file system, so we are sure that the result of get_group_no_and_offset() will not overflow. Otherwise truncate it to the size of the file system. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: update s_free_{inodes,blocks}_count during online resizeDarrick J. Wong2012-03-201-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | When we're doing an online resize of an ext4 filesystem, we need to update the free inode and block counts in the superblock so that fsck doesn't complain. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: change some printk() calls to use ext4_msg() insteadTheodore Ts'o2012-03-206-41/+48
| | | | | | | | | | | | Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: avoid output message interleaving in ext4_error_<foo>()Joe Perches2012-03-201-10/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | Using KERN_CONT means that messages from multiple threads may be interleaved. Avoid this by using a single printk call in ext4_error_inode and ext4_error_file. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: remove trailing newlines from ext4_msg() and ext4_error() messagesTheodore Ts'o2012-03-203-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | The functions ext4_msg() and ext4_error() already tack on a trailing newline, so remove the unnecessary extra newline. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: add no_printk argument validation, fix falloutJoe Perches2012-03-204-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add argument validation to debug functions. Use ##__VA_ARGS__. Fix format and argument mismatches. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: remove redundant "EXT4-fs: " from uses of ext4_msgJoe Perches2012-03-201-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | ext4_msg adds "EXT4-fs: " to the messsage output. Remove the redundant bits from uses. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: give more helpful error message in ext4_ext_rm_leaf()Lukas Czerner2012-03-201-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The error message produced by the ext4_ext_rm_leaf() when we are removing blocks which accidentally ends up inside the existing extent, is not very helpful, because we would like to also know which extent did we collide with. This commit changes the error message to get us also the information about the extent we are colliding with. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: remove unused code from ext4_ext_map_blocks()Lukas Czerner2012-03-201-106/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the commit 'Rewrite punch hole to use ext4_ext_remove_space()' reworked the punch hole implementation to use ext4_ext_remove_space() instead of ext4_ext_map_blocks(), we can remove the code which is no longer needed from the ext4_ext_map_blocks(). Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: rewrite punch hole to use ext4_ext_remove_space()Lukas Czerner2012-03-201-82/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit rewrites ext4 punch hole implementation to use ext4_ext_remove_space() instead of its home gown way of doing this via ext4_ext_map_blocks(). There are several reasons for changing this. Firstly it is quite non obvious that punching hole needs to ext4_ext_map_blocks() to punch a hole, especially given that this function should map blocks, not unmap it. It also required a lot of new code in ext4_ext_map_blocks(). Secondly the design of it is not very effective. The reason is that we are trying to punch out blocks in ext4_ext_punch_hole() in opposite direction than in ext4_ext_rm_leaf() which causes the ext4_ext_rm_leaf() to iterate through the whole tree from the end to the start to find the requested extent for every extent we are going to punch out. And finally the current implementation does not use the existing code, but bring a lot of new code, which is IMO unnecessary since there already is some infrastructure we can use. Specifically ext4_ext_remove_space(). This commit changes ext4_ext_remove_space() to accept 'end' parameter so we can not only truncate to the end of file, but also remove the space in the middle of the file (punch a hole). Moreover, because the last block to punch out, might be in the middle of the extent, we have to split the extent at 'end + 1' so ext4_ext_rm_leaf() can easily either remove the whole fist part of split extent, or change its size. ext4_ext_remove_space() is then used to actually remove the space (extents) from within the hole, instead of ext4_ext_map_blocks(). Note that this also fix the issue with punch hole, where we would forget to remove empty index blocks from the extent tree, resulting in double free block error and file system corruption. This is simply because we now use different code path, where this problem does not exist. This has been tested with fsx running for several days and xfstests, plus xfstest #251 with '-o discard' run on the loop image (which converts discard requestes into punch hole to the backing file). All of it on 1K and 4K file system block size. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: cleanup journal tail after transaction commitJan Kara2012-03-143-0/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Normally, we have to issue a cache flush before we can update journal tail in journal superblock, effectively wiping out old transactions from the journal. So use the fact that during transaction commit we issue cache flush anyway and opportunistically push journal tail as far as we can. Since update of journal superblock is still costly (we have to use WRITE_FUA), we update log tail only if we can free significant amount of space. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: remove bh_state lock from checkpointing codeJan Kara2012-03-142-52/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All accesses to checkpointing entries in journal_head are protected by j_list_lock. Thus __jbd2_journal_remove_checkpoint() doesn't really need bh_state lock. Also the only part of journal head that the rest of checkpointing code needs to check is jh->b_transaction which is safe to read under j_list_lock. So we can safely remove bh_state lock from all of checkpointing code which makes it considerably prettier. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: remove always true condition in __journal_try_to_free_buffer()Jan Kara2012-03-141-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | The check b_jlist == BJ_None in __journal_try_to_free_buffer() is always true (__jbd2_journal_temp_unlink_buffer() also checks this in an assertion) so just remove it. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: declare __jbd2_journal_temp_unlink_buffer() staticJan Kara2012-03-141-2/+2
| | | | | | | | | | | | | | | Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: fix BH_JWrite setting in checkpointing codeJan Kara2012-03-141-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BH_JWrite bit should be set when buffer is written to the journal. So checkpointing shouldn't set this bit when writing out buffer. This didn't cause any observable bug since BH_JWrite bit is used only for debugging purposes but it's good to have this consistent. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: issue cache flush after checkpointing even with internal journalJan Kara2012-03-146-91/+155
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we reach jbd2_cleanup_journal_tail(), there is no guarantee that checkpointed buffers are on a stable storage - especially if buffers were written out by jbd2_log_do_checkpoint(), they are likely to be only in disk's caches. Thus when we update journal superblock effectively removing old transaction from journal, this write of superblock can get to stable storage before those checkpointed buffers which can result in filesystem corruption after a crash. Thus we must unconditionally issue a cache flush before we update journal superblock in these cases. A similar problem can also occur if journal superblock is written only in disk's caches, other transaction starts reusing space of the transaction cleaned from the log and power failure happens. Subsequent journal replay would still try to replay the old transaction but some of it's blocks may be already overwritten by the new transaction. For this reason we must use WRITE_FUA when updating log tail and we must first write new log tail to disk and update in-memory information only after that. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: protect all log tail updates with j_checkpoint_mutexJan Kara2012-03-132-3/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are some log tail updates that are not protected by j_checkpoint_mutex. Some of these are harmless because they happen during startup or shutdown but updates in jbd2_journal_commit_transaction() and jbd2_journal_flush() can really race with other log tail updates (e.g. someone doing jbd2_journal_flush() with someone running jbd2_cleanup_journal_tail()). So protect all log tail updates with j_checkpoint_mutex. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | jbd2: split updating of journal superblock and marking journal emptyJan Kara2012-03-135-79/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are three case of updating journal superblock. In the first case, we want to mark journal as empty (setting s_sequence to 0), in the second case we want to update log tail, in the third case we want to update s_errno. Split these cases into separate functions. It makes the code slightly more straightforward and later patches will make the distinction even more important. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: check for zero length extentTheodore Ts'o2012-03-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Explicitly test for an extent whose length is zero, and flag that as a corrupted extent. This avoids a kernel BUG_ON assertion failure. Tested: Without this patch, the file system image found in tests/f_ext_zero_len/image.gz in the latest e2fsprogs sources causes a kernel panic. With this patch, an ext4 file system error is noted instead, and the file system is marked as being corrupted. https://bugzilla.kernel.org/show_bug.cgi?id=42859 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
| * | ext4: add comments to definition of ext4_io_end_tCurt Wohlgemuth2012-03-051-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | This should make it more clear what this structure is used for, and how some of the (mutually exclusive) fields are used to keep page cache references. Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: don't release page refs in ext4_end_bio()Curt Wohlgemuth2012-03-051-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can clear PageWriteback on each page when the IO completes, but we can't release the references on the page until we convert any uninitialized extents. Without this patch, the use of the dioread_nolock mount option can break buffered writes, because extents may not be converted by the time a subsequent buffered read comes in; if the page is not in the page cache, a read will return zeros if the extent is still uninitialized. I tested this with a (temporary) patch that adds a call to msleep(1000) at the start of ext4_end_io_work(), to delay processing of each DIO-unwritten work queue item. With this msleep(), a simple workload of fallocate write fadvise read will fail without this patch, succeeds with it. Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: fix race between sync and completed io workJeff Moyer2012-03-053-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following command line will leave the aio-stress process unkillable on an ext4 file system (in my case, mounted on /mnt/test): aio-stress -t 20 -s 10 -O -S -o 2 -I 1000 /mnt/test/aiostress.3561.4 /mnt/test/aiostress.3561.4.20 /mnt/test/aiostress.3561.4.19 /mnt/test/aiostress.3561.4.18 /mnt/test/aiostress.3561.4.17 /mnt/test/aiostress.3561.4.16 /mnt/test/aiostress.3561.4.15 /mnt/test/aiostress.3561.4.14 /mnt/test/aiostress.3561.4.13 /mnt/test/aiostress.3561.4.12 /mnt/test/aiostress.3561.4.11 /mnt/test/aiostress.3561.4.10 /mnt/test/aiostress.3561.4.9 /mnt/test/aiostress.3561.4.8 /mnt/test/aiostress.3561.4.7 /mnt/test/aiostress.3561.4.6 /mnt/test/aiostress.3561.4.5 /mnt/test/aiostress.3561.4.4 /mnt/test/aiostress.3561.4.3 /mnt/test/aiostress.3561.4.2 This is using the aio-stress program from the xfstests test suite. That particular command line tells aio-stress to do random writes to 20 files from 20 threads (one thread per file). The files are NOT preallocated, so you will get writes to random offsets within the file, thus creating holes and extending i_size. It also opens the file with O_DIRECT and O_SYNC. On to the problem. When an I/O requires unwritten extent conversion, it is queued onto the completed_io_list for the ext4 inode. Two code paths will pull work items from this list. The first is the ext4_end_io_work routine, and the second is ext4_flush_completed_IO, which is called via the fsync path (and O_SYNC handling, as well). There are two issues I've found in these code paths. First, if the fsync path beats the work routine to a particular I/O, the work routine will free the io_end structure! It does not take into account the fact that the io_end may still be in use by the fsync path. I've fixed this issue by adding yet another IO_END flag, indicating that the io_end is being processed by the fsync path. The second problem is that the work routine will make an assignment to io->flag outside of the lock. I have witnessed this result in a hang at umount. Moving the flag setting inside the lock resolved that problem. The problem was introduced by commit b82e384c7b ("ext4: optimize locking for end_io extent conversion"), which first appeared in 3.2. As such, the fix should be backported to that release (probably along with the unwritten extent conversion race fix). Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> CC: stable@kernel.org
| * | ext4: clean up the flags passed to __blockdev_direct_IOJeff Moyer2012-03-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For extent-based files, you can perform DIO to holes, as mentioned in the comments in ext4_ext_direct_IO. However, that function passes DIO_SKIP_HOLES to __blockdev_direct_IO, which is *really* confusing to the uninitiated reader. The key, here, is that the get_block function passed in, ext4_get_block_write, completely ignores the create flag that is passed to it (the create flag is passed in from the direct I/O code, which uses the DIO_SKIP_HOLES flag to determine whether or not it should be cleared). This is a long-winded way of saying that the DIO_SKIP_HOLES flag is ultimately ignored. So let's remove it. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: try to deprecate noacl and noxattr_user mount optionsTheodore Ts'o2012-03-051-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | No other file system allows ACL's and extended attributes to be enabled or disabled via a mount option. So let's try to deprecate these options from ext4. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: ignore mount options supported by ext2/3 (but have since been removed)Theodore Ts'o2012-03-051-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Users who tried to use the ext4 file system driver is being used for the ext2 or ext3 file systems (via the CONFIG_EXT4_USE_FOR_EXT23 option) could have failed mounts if their /etc/fstab contains options recognized by ext2 or ext3 but which have since been removed in ext4. So teach ext4 to recognize them and give a warning that the mount option was removed. Report: https://bbs.archlinux.org/profile.php?id=33804 Signed-off-by: Tom Gundersen <teg@jklm.no> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Thomas Baechler <thomas@archlinux.org> Cc: Tobias Powalowski <tobias.powalowski@googlemail.com> Cc: Dave Reisner <d@falconindy.com>
| * | ext4: add debugging /proc file showing file system optionsTheodore Ts'o2012-03-051-17/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that /proc/mounts is consistently showing only those mount options which need to be specified in /etc/fstab or on the mount command line, it is useful to have file which shows exactly which file system options are enabled. This can be useful when debugging a user problem. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: make ext4_show_options() be table-drivenTheodore Ts'o2012-03-052-111/+62
| | | | | | | | | | | | | | | | | | | | | | | | Consistently show mount options which are the non-default, so that /proc/mounts accurately shows the mount options that would be necessary to mount the file system in its current mode of operation. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: move ext4_show_options() after parse_options()Theodore Ts'o2012-03-041-174/+175
| | | | | | | | | | | | | | | | | | | | | This commit is strictly a code movement so in preparation of changing ext4_show_options to be table driven. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: use a table-driven handler for mount optionsTheodore Ts'o2012-03-041-336/+234
| | | | | | | | | | | | | | | | | | | | | | | | | | | By using a table-drive approach, we shave about 100 lines of code from ext4, and make the code a bit more regular and factored out. This will also make it possible in a future patch to use this table for displaying the mount options that were specified in /proc/mounts. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * | ext4: unify handling of mount options which have been removedTheodore Ts'o2012-03-041-20/+8
| | | | | | | | | | | | Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>