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* lseek: the "whence" argument is called "whence"Andrew Morton2012-12-171-10/+10
| | | | | | | | | But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs: support SEEK_DATA and SEEK_HOLE (reprise)Hugh Dickins2012-12-121-1/+91
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert 3.5's commit f21f8062201f ("tmpfs: revert SEEK_DATA and SEEK_HOLE") to reinstate 4fb5ef089b28 ("tmpfs: support SEEK_DATA and SEEK_HOLE"), with the intervening additional arg to generic_file_llseek_size(). In 3.8, ext4 is expected to join btrfs, ocfs2 and xfs with proper SEEK_DATA and SEEK_HOLE support; and a good case has now been made for it on tmpfs, so let's join the party. It's quite easy for tmpfs to scan the radix_tree to support llseek's new SEEK_DATA and SEEK_HOLE options: so add them while the minutiae are still on my mind (in particular, the !PageUptodate-ness of pages fallocated but still unwritten). [akpm@linux-foundation.org: fix warning with CONFIG_TMPFS=n] Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jaegeuk Hanse <jaegeuk.hanse@gmail.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Zheng Liu <wenqing.lz@taobao.com> Cc: Jeff liu <jeff.liu@oracle.com> Cc: Paul Eggert <eggert@cs.ucla.edu> Cc: Christoph Hellwig <hch@infradead.org> Cc: Josef Bacik <josef@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Andreas Dilger <adilger@dilger.ca> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Chris Mason <chris.mason@fusionio.com> Cc: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs: fix shared mempolicy leakMel Gorman2012-12-061-10/+16
| | | | | | | | | | | | | | | | | | | | | | | This fixes a regression in 3.7-rc, which has since gone into stable. Commit 00442ad04a5e ("mempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()") changed get_vma_policy() to raise the refcount on a shmem shared mempolicy; whereas shmem_alloc_page() went on expecting alloc_page_vma() to drop the refcount it had acquired. This deserves a rework: but for now fix the leak in shmem_alloc_page(). Hugh: shmem_swapin() did not need a fix, but surely it's clearer to use the same refcounting there as in shmem_alloc_page(), delete its onstack mempolicy, and the strange mpol_cond_copy() and __mpol_cond_copy() - those were invented to let swapin_readahead() make an unknown number of calls to alloc_pages_vma() with one mempolicy; but since 00442ad04a5e, alloc_pages_vma() has kept refcount in balance, so now no problem. Reported-and-tested-by: Tommi Rantala <tt.rantala@gmail.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs: change final i_blocks BUG to WARNINGHugh Dickins2012-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Under a particular load on one machine, I have hit shmem_evict_inode()'s BUG_ON(inode->i_blocks), enough times to narrow it down to a particular race between swapout and eviction. It comes from the "if (freed > 0)" asymmetry in shmem_recalc_inode(), and the lack of coherent locking between mapping's nrpages and shmem's swapped count. There's a window in shmem_writepage(), between lowering nrpages in shmem_delete_from_page_cache() and then raising swapped count, when the freed count appears to be +1 when it should be 0, and then the asymmetry stops it from being corrected with -1 before hitting the BUG. One answer is coherent locking: using tree_lock throughout, without info->lock; reasonable, but the raw_spin_lock in percpu_counter_add() on used_blocks makes that messier than expected. Another answer may be a further effort to eliminate the weird shmem_recalc_inode() altogether, but previous attempts at that failed. So far undecided, but for now change the BUG_ON to WARN_ON: in usual circumstances it remains a useful consistency check. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs: fix shmem_getpage_gfp() VM_BUG_ONHugh Dickins2012-11-161-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fuzzing with trinity hit the "impossible" VM_BUG_ON(error) (which Fedora has converted to WARNING) in shmem_getpage_gfp(): WARNING: at mm/shmem.c:1151 shmem_getpage_gfp+0xa5c/0xa70() Pid: 29795, comm: trinity-child4 Not tainted 3.7.0-rc2+ #49 Call Trace: warn_slowpath_common+0x7f/0xc0 warn_slowpath_null+0x1a/0x20 shmem_getpage_gfp+0xa5c/0xa70 shmem_fault+0x4f/0xa0 __do_fault+0x71/0x5c0 handle_pte_fault+0x97/0xae0 handle_mm_fault+0x289/0x350 __do_page_fault+0x18e/0x530 do_page_fault+0x2b/0x50 page_fault+0x28/0x30 tracesys+0xe1/0xe6 Thanks to Johannes for pointing to truncation: free_swap_and_cache() only does a trylock on the page, so the page lock we've held since before confirming swap is not enough to protect against truncation. What cleanup is needed in this case? Just delete_from_swap_cache(), which takes care of the memcg uncharge. Signed-off-by: Hugh Dickins <hughd@google.com> Reported-by: Dave Jones <davej@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checkingHugh Dickins2012-10-091-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(), u64 inum = fid->raw[2]; which is unhelpfully reported as at the end of shmem_alloc_inode(): BUG: unable to handle kernel paging request at ffff880061cd3000 IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Call Trace: [<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0 [<ffffffff812d77c3>] do_handle_open+0x163/0x2c0 [<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10 [<ffffffff83a5f3f8>] tracesys+0xe1/0xe6 Right, tmpfs is being stupid to access fid->raw[2] before validating that fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may fall at the end of a page, and the next page not be present. But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and could oops in the same way: add the missing fh_len checks to those. Reported-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Sage Weil <sage@inktank.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mm: kill vma flag VM_CAN_NONLINEARKonstantin Khlebnikov2012-10-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move actual pte filling for non-linear file mappings into the new special vma operation: ->remap_pages(). Filesystems must implement this method to get non-linear mapping support, if it uses filemap_fault() then generic_file_remap_pages() can be used. Now device drivers can implement this method and obtain nonlinear vma support. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* xattr: extract simple_xattr code from tmpfsAristeu Rozanski2012-08-241-158/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extract in-memory xattr APIs from tmpfs. Will be used by cgroup. $ size vmlinux.o text data bss dec hex filename 4658782 880729 5195032 10734543 a3cbcf vmlinux.o $ size vmlinux.o text data bss dec hex filename 4658957 880729 5195032 10734718 a3cc7e vmlinux.o v7: - checkpatch warnings fixed - Implement the changes requested by Hugh Dickins: - make simple_xattrs_init and simple_xattrs_free inline - get rid of locking and list reinitialization in simple_xattrs_free, they're not needed v6: - no changes v5: - no changes v4: - move simple_xattrs_free() to fs/xattr.c v3: - in kmem_xattrs_free(), reinitialize the list - use simple_xattr_* prefix - introduce simple_xattr_add() to prevent direct list usage Original-patch-by: Li Zefan <lizefan@huawei.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* tmpfs: distribute interleave better across nodesNathan Zimmer2012-07-311-2/+4
| | | | | | | | | | | | | | | | | | | | When tmpfs has the interleave memory policy, it always starts allocating for each file from node 0 at offset 0. When there are many small files, the lower nodes fill up disproportionately. This patch spreads out node usage by starting files at nodes other than 0, by using the inode number to bias the starting node for interleave. Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Nick Piggin <npiggin@gmail.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* don't pass nameidata to ->create()Al Viro2012-07-141-1/+1
| | | | | | | | boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* shmem: cleanup shmem_add_to_page_cacheHugh Dickins2012-07-111-30/+28
| | | | | | | | | | | | | | | | | shmem_add_to_page_cache() has three callsites, but only one of them wants the radix_tree_preload() (an exceptional entry guarantees that the radix tree node is present in the other cases), and only that site can achieve mem_cgroup_uncharge_cache_page() (PageSwapCache makes it a no-op in the other cases). We did it this way originally to reflect add_to_page_cache_locked(); but it's confusing now, so move the radix_tree preloading and mem_cgroup uncharging to that one caller. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.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>
* shmem: fix negative rss in memcg memory.statHugh Dickins2012-07-111-12/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When adding the page_private checks before calling shmem_replace_page(), I did realize that there is a further race, but thought it too unlikely to need a hurried fix. But independently I've been chasing why a mem cgroup's memory.stat sometimes shows negative rss after all tasks have gone: I expected it to be a stats gathering bug, but actually it's shmem swapping's fault. It's an old surprise, that when you lock_page(lookup_swap_cache(swap)), the page may have been removed from swapcache before getting the lock; or it may have been freed and reused and be back in swapcache; and it can even be using the same swap location as before (page_private same). The swapoff case is already secure against this (swap cannot be reused until the whole area has been swapped off, and a new swapped on); and shmem_getpage_gfp() is protected by shmem_add_to_page_cache()'s check for the expected radix_tree entry - but a little too late. By that time, we might have already decided to shmem_replace_page(): I don't know of a problem from that, but I'd feel more at ease not to do so spuriously. And we have already done mem_cgroup_cache_charge(), on perhaps the wrong mem cgroup: and this charge is not then undone on the error path, because PageSwapCache ends up preventing that. It's this last case which causes the occasional negative rss in memory.stat: the page is charged here as cache, but (sometimes) found to be anon when eventually it's uncharged - and in between, it's an undeserved charge on the wrong memcg. Fix this by adding an earlier check on the radix_tree entry: it's inelegant to descend the tree twice, but swapping is not the fast path, and a better solution would need a pair (try+commit) of memcg calls, and a rework of shmem_replace_page() to keep out of the swapcache. We can use the added shmem_confirm_swap() function to replace the find_get_page+page_cache_release we were already doing on the error path. And add a comment on that -EEXIST: it seems a peculiar errno to be using, but originates from its use in radix_tree_insert(). [It can be surprising to see positive rss left in a memcg's memory.stat after all tasks have gone, since it is supposed to count anonymous but not shmem. Aside from sharing anon pages via fork with a task in some other memcg, it often happens after swapping: because a swap page can't be freed while under writeback, nor while locked. So it's not an error, and these residual pages are easily freed once pressure demands.] Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.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>
* tmpfs: revert SEEK_DATA and SEEK_HOLEHugh Dickins2012-07-111-93/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Revert 4fb5ef089b28 ("tmpfs: support SEEK_DATA and SEEK_HOLE"). I believe it's correct, and it's been nice to have from rc1 to rc6; but as the original commit said: I don't know who actually uses SEEK_DATA or SEEK_HOLE, and whether it would be of any use to them on tmpfs. This code adds 92 lines and 752 bytes on x86_64 - is that bloat or worthwhile? Nobody asked for it, so I conclude that it's bloat: let's revert tmpfs to the dumb generic support for v3.5. We can always reinstate it later if useful, and anyone needing it in a hurry can just get it out of git. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Josef Bacik <josef@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Andreas Dilger <adilger@dilger.ca> Cc: Dave Chinner <david@fromorbit.com> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Jeff liu <jeff.liu@oracle.com> Cc: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds2012-07-031-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block bits from Jens Axboe: "As vacation is coming up, thought I'd better get rid of my pending changes in my for-linus branch for this iteration. It contains: - Two patches for mtip32xx. Killing a non-compliant sysfs interface and moving it to debugfs, where it belongs. - A few patches from Asias. Two legit bug fixes, and one killing an interface that is no longer in use. - A patch from Jan, making the annoying partition ioctl warning a bit less annoying, by restricting it to !CAP_SYS_RAWIO only. - Three bug fixes for drbd from Lars Ellenberg. - A fix for an old regression for umem, it hasn't really worked since the plugging scheme was changed in 3.0. - A few fixes from Tejun. - A splice fix from Eric Dumazet, fixing an issue with pipe resizing." * 'for-linus' of git://git.kernel.dk/linux-block: scsi: Silence unnecessary warnings about ioctl to partition block: Drop dead function blk_abort_queue() block: Mitigate lock unbalance caused by lock switching block: Avoid missed wakeup in request waitqueue umem: fix up unplugging splice: fix racy pipe->buffers uses drbd: fix null pointer dereference with on-congestion policy when diskless drbd: fix list corruption by failing but already aborted reads drbd: fix access of unallocated pages and kernel panic xen/blkfront: Add WARN to deal with misbehaving backends. blkcg: drop local variable @q from blkg_destroy() mtip32xx: Create debugfs entries for troubleshooting mtip32xx: Remove 'registers' and 'flags' from sysfs blkcg: fix blkg_alloc() failure path block: blkcg_policy_cfq shouldn't be used if !CONFIG_CFQ_GROUP_IOSCHED block: fix return value on cfq_init() failure mtip32xx: Remove version.h header file inclusion xen/blkback: Copy id field when doing BLKIF_DISCARD.
| * splice: fix racy pipe->buffers usesEric Dumazet2012-06-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dave Jones reported a kernel BUG at mm/slub.c:3474! triggered by splice_shrink_spd() called from vmsplice_to_pipe() commit 35f3d14dbbc5 (pipe: add support for shrinking and growing pipes) added capability to adjust pipe->buffers. Problem is some paths don't hold pipe mutex and assume pipe->buffers doesn't change for their duration. Fix this by adding nr_pages_max field in struct splice_pipe_desc, and use it in place of pipe->buffers where appropriate. splice_shrink_spd() loses its struct pipe_inode_info argument. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Tom Herbert <therbert@google.com> Cc: stable <stable@vger.kernel.org> # 2.6.35 Tested-by: Dave Jones <davej@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | shmem: replace_page must flush_dcache and othersHugh Dickins2012-06-071-20/+37
|/ | | | | | | | | | | | | | | | | | | | | | | | | Commit bde05d1ccd51 ("shmem: replace page if mapping excludes its zone") is not at all likely to break for anyone, but it was an earlier version from before review feedback was incorporated. Fix that up now. * shmem_replace_page must flush_dcache_page after copy_highpage [akpm] * Expand comment on why shmem_unuse_inode needs page_swapcount [akpm] * Remove excess of VM_BUG_ONs from shmem_replace_page [wangcong] * Check page_private matches swap before calling shmem_replace_page [hughd] * shmem_replace_page allow for unexpected race in radix_tree lookup [hughd] Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephane Marchesin <marcheu@chromium.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Dave Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Rob Clark <rob.clark@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-06-011-4/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs changes from Al Viro. "A lot of misc stuff. The obvious groups: * Miklos' atomic_open series; kills the damn abuse of ->d_revalidate() by NFS, which was the major stumbling block for all work in that area. * ripping security_file_mmap() and dealing with deadlocks in the area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in general. * ->encode_fh() switched to saner API; insane fake dentry in mm/cleancache.c gone. * assorted annotations in fs (endianness, __user) * parts of Artem's ->s_dirty work (jff2 and reiserfs parts) * ->update_time() work from Josef. * other bits and pieces all over the place. Normally it would've been in two or three pull requests, but signal.git stuff had eaten a lot of time during this cycle ;-/" Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the 'truncate_range' inode method was removed by the VM changes, the VFS update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due to sparse fix added twice, with other changes nearby). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits) nfs: don't open in ->d_revalidate vfs: retry last component if opening stale dentry vfs: nameidata_to_filp(): don't throw away file on error vfs: nameidata_to_filp(): inline __dentry_open() vfs: do_dentry_open(): don't put filp vfs: split __dentry_open() vfs: do_last() common post lookup vfs: do_last(): add audit_inode before open vfs: do_last(): only return EISDIR for O_CREAT vfs: do_last(): check LOOKUP_DIRECTORY vfs: do_last(): make ENOENT exit RCU safe vfs: make follow_link check RCU safe vfs: do_last(): use inode variable vfs: do_last(): inline walk_component() vfs: do_last(): make exit RCU safe vfs: split do_lookup() Btrfs: move over to use ->update_time fs: introduce inode operation ->update_time reiserfs: get rid of resierfs_sync_super reiserfs: mark the superblock as dirty a bit later ...
| * ->encode_fh() API changeAl Viro2012-05-291-4/+2
| | | | | | | | | | | | | | | | | | pass inode + parent's inode or NULL instead of dentry + bool saying whether we want the parent or not. NOTE: that needs ceph fix folded in. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | tmpfs: support SEEK_DATA and SEEK_HOLEHugh Dickins2012-05-291-1/+93
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's quite easy for tmpfs to scan the radix_tree to support llseek's new SEEK_DATA and SEEK_HOLE options: so add them while the minutiae are still on my mind (in particular, the !PageUptodate-ness of pages fallocated but still unwritten). But I don't know who actually uses SEEK_DATA or SEEK_HOLE, and whether it would be of any use to them on tmpfs. This code adds 92 lines and 752 bytes on x86_64 - is that bloat or worthwhile? [akpm@linux-foundation.org: fix warning with CONFIG_TMPFS=n] Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Josef Bacik <josef@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Andreas Dilger <adilger@dilger.ca> Cc: Dave Chinner <david@fromorbit.com> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Jeff liu <jeff.liu@oracle.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tmpfs: quit when fallocate fills memoryHugh Dickins2012-05-291-2/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As it stands, a large fallocate() on tmpfs is liable to fill memory with pages, freed on failure except when they run into swap, at which point they become fixed into the file despite the failure. That feels quite wrong, to be consuming resources precisely when they're in short supply. Go the other way instead: shmem_fallocate() indicate the range it has fallocated to shmem_writepage(), keeping count of pages it's allocating; shmem_writepage() reactivate instead of swapping out pages fallocated by this syscall (but happily swap out those from earlier occasions), keeping count; shmem_fallocate() compare counts and give up once the reactivated pages have started to coming back to writepage (approximately: some zones would in fact recycle faster than others). This is a little unusual, but works well: although we could consider the failure to swap as a bug, and fix it later with SWAP_MAP_FALLOC handling added in swapfile.c and memcontrol.c, I doubt that we shall ever want to. (If there's no swap, an over-large fallocate() on tmpfs is limited in the same way as writing: stopped by rlimit, or by tmpfs mount size if that was set sensibly, or by __vm_enough_memory() heuristics if OVERCOMMIT_GUESS or OVERCOMMIT_NEVER. If OVERCOMMIT_ALWAYS, then it is liable to OOM-kill others as writing would, but stops and frees if interrupted.) Now that everything is freed on failure, we can then skip updating ctime. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Cong Wang <amwang@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tmpfs: undo fallocation on failureHugh Dickins2012-05-291-33/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the previous episode, we left the already-fallocated pages attached to the file when shmem_fallocate() fails part way through. Now try to do better, by extending the earlier optimization of !Uptodate pages (then always under page lock) to !Uptodate pages (outside of page lock), representing fallocated pages. And don't waste time clearing them at the time of fallocate(), leave that until later if necessary. Adapt shmem_truncate_range() to shmem_undo_range(), so that a failing fallocate can recognize and remove precisely those !Uptodate allocations which it added (and were not independently allocated by racing tasks). But unless we start playing with swapfile.c and memcontrol.c too, once one of our fallocated pages reaches shmem_writepage(), we do then have to instantiate it as an ordinarily allocated page, before swapping out. This is unsatisfactory, but improved in the next episode. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Cong Wang <amwang@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tmpfs: support fallocate preallocationHugh Dickins2012-05-291-1/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The systemd plumbers expressed a wish that tmpfs support preallocation. Cong Wang wrote a patch, but several kernel guys expressed scepticism: https://lkml.org/lkml/2011/11/18/137 Christoph Hellwig: What for exactly? Please explain why preallocating on tmpfs would make any sense. Kay Sievers: To be able to safely use mmap(), regarding SIGBUS, on files on the /dev/shm filesystem. The glibc fallback loop for -ENOSYS [or -EOPNOTSUPP] on fallocate is just ugly. Hugh Dickins: If tmpfs is going to support fallocate(FALLOC_FL_PUNCH_HOLE), it would seem perverse to permit the deallocation but fail the allocation. Christoph Hellwig: Agreed. Now that we do have shmem_fallocate() for hole-punching, plumb in basic support for preallocation mode too. It's fairly straightforward (though quite a few details needed attention), except for when it fails part way through. What a pity that fallocate(2) was not specified to return the length allocated, permitting short fallocations! As it is, when it fails part way through, we ought to free what has just been allocated by this system call; but must be very sure not to free any allocated earlier, or any allocated by racing accesses (not all excluded by i_mutex). But we cannot distinguish them: so in this patch simply leak allocations on partial failure (they will be freed later if the file is removed). An attractive alternative approach would have been for fallocate() not to allocate pages at all, but note reservations by entries in the radix-tree. But that would give less assurance, and, critically, would be hard to fit with mem cgroups (who owns the reservations?): allocating pages lets fallocate() behave in just the same way as write(). Based-on-patch-by: Cong Wang <amwang@redhat.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Cong Wang <amwang@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm/fs: remove truncate_rangeHugh Dickins2012-05-291-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove vmtruncate_range(), and remove the truncate_range method from struct inode_operations: only tmpfs ever supported it, and tmpfs has now converted over to using the fallocate method of file_operations. Update Documentation accordingly, adding (setlease and) fallocate lines. And while we're in mm.h, remove duplicate declarations of shmem_lock() and shmem_file_setup(): everyone is now using the ones in shmem_fs.h. Based-on-patch-by: Cong Wang <amwang@redhat.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Cong Wang <amwang@redhat.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>
* | tmpfs: support fallocate FALLOC_FL_PUNCH_HOLEHugh Dickins2012-05-291-11/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tmpfs has supported hole-punching since 2.6.16, via madvise(,,MADV_REMOVE). But nowadays fallocate(,FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE,,) is the agreed way to punch holes. So add shmem_fallocate() to support that, and tweak shmem_truncate_range() to support partial pages at both the beginning and end of range (never needed for madvise, which demands rounded addr and rounds up length). Based-on-patch-by: Cong Wang <amwang@redhat.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Cong Wang <amwang@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tmpfs: optimize clearing when writingHugh Dickins2012-05-291-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nick proposed years ago that tmpfs should avoid clearing its pages where write will overwrite them with new data, as ramfs has long done. But I messed it up and just got bad data. Tried again recently, it works fine. Here's time output for writing 4GiB 16 times on this Core i5 laptop: before: real 0m21.169s user 0m0.028s sys 0m21.057s real 0m21.382s user 0m0.016s sys 0m21.289s real 0m21.311s user 0m0.020s sys 0m21.217s after: real 0m18.273s user 0m0.032s sys 0m18.165s real 0m18.354s user 0m0.020s sys 0m18.265s real 0m18.440s user 0m0.032s sys 0m18.337s ramfs: real 0m16.860s user 0m0.028s sys 0m16.765s real 0m17.382s user 0m0.040s sys 0m17.273s real 0m17.133s user 0m0.044s sys 0m17.021s Yes, I have done perf reports, but they need more explanation than they deserve: in summary, clear_page vanishes, its cache loading shifts into copy_user_generic_unrolled; shmem_getpage_gfp goes down, and surprisingly mark_page_accessed goes way up - I think because they are respectively where the cache gets to be reloaded after being purged by clear or copy. Suggested-by: Nick Piggin <npiggin@gmail.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | tmpfs: enable NOSEC optimizationHugh Dickins2012-05-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Let tmpfs into the NOSEC optimization (avoiding file_remove_suid() overhead on most common writes): set MS_NOSEC on its superblocks. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | shmem: replace page if mapping excludes its zoneHugh Dickins2012-05-291-19/+122
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The GMA500 GPU driver uses GEM shmem objects, but with a new twist: the backing RAM has to be below 4GB. Not a problem while the boards supported only 4GB: but now Intel's D2700MUD boards support 8GB, and their GMA3600 is managed by the GMA500 driver. shmem/tmpfs has never pretended to support hardware restrictions on the backing memory, but it might have appeared to do so before v3.1, and even now it works fine until a page is swapped out then back in. When read_cache_page_gfp() supplied a freshly allocated page for copy, that compensated for whatever choice might have been made by earlier swapin readahead; but swapoff was likely to destroy the illusion. We'd like to continue to support GMA500, so now add a new shmem_should_replace_page() check on the zone when about to move a page from swapcache to filecache (in swapin and swapoff cases), with shmem_replace_page() to allocate and substitute a suitable page (given gma500/gem.c's mapping_set_gfp_mask GFP_KERNEL | __GFP_DMA32). This does involve a minor extension to mem_cgroup_replace_page_cache() (the page may or may not have already been charged); and I've removed a comment and call to mem_cgroup_uncharge_cache_page(), which in fact is always a no-op while PageSwapCache. Also removed optimization of an unlikely path in shmem_getpage_gfp(), now that we need to check PageSwapCache more carefully (a racing caller might already have made the copy). And at one point shmem_unuse_inode() needs to use the hitherto private page_swapcount(), to guard against racing with inode eviction. It would make sense to extend shmem_should_replace_page(), to cover cpuset and NUMA mempolicy restrictions too, but set that aside for now: needs a cleanup of shmem mempolicy handling, and more testing, and ought to handle swap faults in do_swap_page() as well as shmem. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephane Marchesin <marcheu@chromium.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Dave Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Rob Clark <rob.clark@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linuxLinus Torvalds2012-05-281-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull writeback tree from Wu Fengguang: "Mainly from Jan Kara to avoid iput() in the flusher threads." * tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Avoid iput() from flusher thread vfs: Rename end_writeback() to clear_inode() vfs: Move waiting for inode writeback from end_writeback() to evict_inode() writeback: Refactor writeback_single_inode() writeback: Remove wb->list_lock from writeback_single_inode() writeback: Separate inode requeueing after writeback writeback: Move I_DIRTY_PAGES handling writeback: Move requeueing when I_SYNC set to writeback_sb_inodes() writeback: Move clearing of I_SYNC into inode_sync_complete() writeback: initialize global_dirty_limit fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds mm: page-writeback.c: local functions should not be exposed globally
| * vfs: Rename end_writeback() to clear_inode()Jan Kara2012-05-061-1/+1
| | | | | | | | | | | | | | | | | | After we moved inode_sync_wait() from end_writeback() it doesn't make sense to call the function end_writeback() anymore. Rename it to clear_inode() which well says what the function really does - set I_CLEAR flag. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* | userns: Convert tmpfs to use kuid and kgid where appropriateEric W. Biederman2012-05-151-6/+16
|/ | | | | Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds2012-03-221-16/+72
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge first batch of patches from Andrew Morton: "A few misc things and all the MM queue" * emailed from Andrew Morton <akpm@linux-foundation.org>: (92 commits) memcg: avoid THP split in task migration thp: add HPAGE_PMD_* definitions for !CONFIG_TRANSPARENT_HUGEPAGE memcg: clean up existing move charge code mm/memcontrol.c: remove unnecessary 'break' in mem_cgroup_read() mm/memcontrol.c: remove redundant BUG_ON() in mem_cgroup_usage_unregister_event() mm/memcontrol.c: s/stealed/stolen/ memcg: fix performance of mem_cgroup_begin_update_page_stat() memcg: remove PCG_FILE_MAPPED memcg: use new logic for page stat accounting memcg: remove PCG_MOVE_LOCK flag from page_cgroup memcg: simplify move_account() check memcg: remove EXPORT_SYMBOL(mem_cgroup_update_page_stat) memcg: kill dead prev_priority stubs memcg: remove PCG_CACHE page_cgroup flag memcg: let css_get_next() rely upon rcu_read_lock() cgroup: revert ss_id_lock to spinlock idr: make idr_get_next() good for rcu_read_lock() memcg: remove unnecessary thp check in page stat accounting memcg: remove redundant returns memcg: enum lru_list lru ...
| * tmpfs: security xattr setting on inode creationJarkko Sakkinen2012-03-211-16/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | Adds to generic xattr support introduced in Linux 3.0 by implementing initxattrs callback. This enables consulting of security attributes from LSM and EVM when inode is created. [hughd@google.com: moved under CONFIG_TMPFS_XATTR, with memcpy in shmem_xattr_alloc] Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Reviewed-by: James Morris <james.l.morris@oracle.com> 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>
* | Merge branch 'for-linus' of ↵Linus Torvalds2012-03-211-7/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
| * | tidy up after d_make_root() conversionAl Viro2012-03-201-4/+2
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | switch open-coded instances of d_make_root() to new helperAl Viro2012-03-201-4/+2
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | Merge branch 'next' of ↵Linus Torvalds2012-03-211-2/+2
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates for 3.4 from James Morris: "The main addition here is the new Yama security module from Kees Cook, which was discussed at the Linux Security Summit last year. Its purpose is to collect miscellaneous DAC security enhancements in one place. This also marks a departure in policy for LSM modules, which were previously limited to being standalone access control systems. Chromium OS is using Yama, and I believe there are plans for Ubuntu, at least. This patchset also includes maintenance updates for AppArmor, TOMOYO and others." Fix trivial conflict in <net/sock.h> due to the jumo_label->static_key rename. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits) AppArmor: Fix location of const qualifier on generated string tables TOMOYO: Return error if fails to delete a domain AppArmor: add const qualifiers to string arrays AppArmor: Add ability to load extended policy TOMOYO: Return appropriate value to poll(). AppArmor: Move path failure information into aa_get_name and rename AppArmor: Update dfa matching routines. AppArmor: Minor cleanup of d_namespace_path to consolidate error handling AppArmor: Retrieve the dentry_path for error reporting when path lookup fails AppArmor: Add const qualifiers to generated string tables AppArmor: Fix oops in policy unpack auditing AppArmor: Fix error returned when a path lookup is disconnected KEYS: testing wrong bit for KEY_FLAG_REVOKED TOMOYO: Fix mount flags checking order. security: fix ima kconfig warning AppArmor: Fix the error case for chroot relative path name lookup AppArmor: fix mapping of META_READ to audit and quiet flags AppArmor: Fix underflow in xindex calculation AppArmor: Fix dropping of allowed operations that are force audited AppArmor: Add mising end of structure test to caps unpacking ...
| * | mm: collapse security_vm_enough_memory() variants into a single functionAl Viro2012-02-141-2/+2
| |/ | | | | | | | | | | | | Collapse security_vm_enough_memory() variants into a single function. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Morris <jmorris@namei.org>
* / mm: remove the second argument of k[un]map_atomic()Cong Wang2012-03-201-2/+2
|/ | | | Signed-off-by: Cong Wang <amwang@redhat.com>
* SHM_UNLOCK: fix Unevictable pages stranded after swapHugh Dickins2012-01-231-5/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit cc39c6a9bbde ("mm: account skipped entries to avoid looping in find_get_pages") correctly fixed an infinite loop; but left a problem that find_get_pages() on shmem would return 0 (appearing to callers to mean end of tree) when it meets a run of nr_pages swap entries. The only uses of find_get_pages() on shmem are via pagevec_lookup(), called from invalidate_mapping_pages(), and from shmctl SHM_UNLOCK's scan_mapping_unevictable_pages(). The first is already commented, and not worth worrying about; but the second can leave pages on the Unevictable list after an unusual sequence of swapping and locking. Fix that by using shmem_find_get_pages_and_swap() (then ignoring the swap) instead of pagevec_lookup(). But I don't want to contaminate vmscan.c with shmem internals, nor shmem.c with LRU locking. So move scan_mapping_unevictable_pages() into shmem.c, renaming it shmem_unlock_mapping(); and rename check_move_unevictable_page() to check_move_unevictable_pages(), looping down an array of pages, oftentimes under the same lock. Leave out the "rotate unevictable list" block: that's a leftover from when this was used for /proc/sys/vm/scan_unevictable_pages, whose flawed handling involved looking at pages at tail of LRU. Was there significance to the sequence first ClearPageUnevictable, then test page_evictable, then SetPageUnevictable here? I think not, we're under LRU lock, and have no barriers between those. Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Cc: <stable@vger.kernel.org> [back to 3.1 but will need respins] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SHM_UNLOCK: fix long unpreemptible sectionHugh Dickins2012-01-231-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | scan_mapping_unevictable_pages() is used to make SysV SHM_LOCKed pages evictable again once the shared memory is unlocked. It does this with pagevec_lookup()s across the whole object (which might occupy most of memory), and takes 300ms to unlock 7GB here. A cond_resched() every PAGEVEC_SIZE pages would be good. However, KOSAKI-san points out that this is called under shmem.c's info->lock, and it's also under shm.c's shm_lock(), both spinlocks. There is no strong reason for that: we need to take these pages off the unevictable list soonish, but those locks are not required for it. So move the call to scan_mapping_unevictable_pages() from shmem.c's unlock handling up to shm.c's unlock handling. Remove the recently added barrier, not needed now we have spin_unlock() before the scan. Use get_file(), with subsequent fput(), to make sure we have a reference to mapping throughout scan_mapping_unevictable_pages(): that's something that was previously guaranteed by the shm_lock(). Remove shmctl's lru_add_drain_all(): we don't fault in pages at SHM_LOCK time, and we lazily discover them to be Unevictable later, so it serves no purpose for SHM_LOCK; and serves no purpose for SHM_UNLOCK, since pages still on pagevec are not marked Unevictable. The original code avoided redundant rescans by checking VM_LOCKED flag at its level: now avoid them by checking shp's SHM_LOCKED. The original code called scan_mapping_unevictable_pages() on a locked area at shm_destroy() time: perhaps we once had accounting cross-checks which required that, but not now, so skip the overhead and just let inode eviction deal with them. Put check_move_unevictable_page() and scan_mapping_unevictable_pages() under CONFIG_SHMEM (with stub for the TINY case when ramfs is used), more as comment than to save space; comment them used for SHM_UNLOCK. Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: switch ->show_options() to struct dentry *Al Viro2012-01-061-2/+2
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* shmem, ramfs: propagate umode_t, open-coded S_ISREGAl Viro2012-01-031-3/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch ->mknod() to umode_tAl Viro2012-01-031-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch ->create() to umode_tAl Viro2012-01-031-1/+1
| | | | | | | | vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch vfs_mkdir() and ->mkdir() to umode_tAl Viro2012-01-031-1/+1
| | | | | | | vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: fix the stupidity with i_dentry in inode destructorsAl Viro2012-01-031-1/+0
| | | | | | | | | | Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds2011-11-061-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
| * mm: Map most files to use export.h instead of module.hPaul Gortmaker2011-10-311-1/+1
| | | | | | | | | | | | | | | | The files changed within are only using the EXPORT_SYMBOL macro variants. They are not using core modular infrastructure and hence don't need module.h but only the export.h header. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | filesystems: add missing nlink wrappersMiklos Szeredi2011-11-021-1/+1
| | | | | | | | | | | | | | Replace direct i_nlink updates with the respective updater function (inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* | vmscan: add barrier to prevent evictable page in unevictable listMinchan Kim2011-10-311-0/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a race between putback_lru_page() and shmem_lock with lock=0 happens, progrom execution order is as follows, but clear_bit in processor #1 could be reordered right before spin_unlock of processor #1. Then, the page would be stranded on the unevictable list. spin_lock SetPageLRU spin_unlock clear_bit(AS_UNEVICTABLE) spin_lock if PageLRU() if !test_bit(AS_UNEVICTABLE) move evictable list smp_mb if !test_bit(AS_UNEVICTABLE) move evictable list spin_unlock But, pagevec_lookup() in scan_mapping_unevictable_pages() has rcu_read_[un]lock() so it could protect reordering before reaching test_bit(AS_UNEVICTABLE) on processor #1 so this problem never happens. But it's a unexpected side effect and we should solve this problem properly. This patch adds a barrier after mapping_clear_unevictable. I didn't meet this problem but just found during review. Signed-off-by: Minchan Kim <minchan.kim@gmail.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Acked-by: Johannes Weiner <jweiner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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