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* hlist: drop the node parameter from iteratorsSasha Levin2013-02-271-12/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* new helper: file_inode(file)Al Viro2013-02-221-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mm: redefine address_space.assoc_mappingRafael Aquini2012-12-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | Overhaul struct address_space.assoc_mapping renaming it to address_space.private_data and its type is redefined to void*. By this approach we consistently name the .private_* elements from struct address_space as well as allow extended usage for address_space association with other data structures through ->private_data. Also, all users of old ->assoc_mapping element are converted to reflect its new name and type change (->private_data). Signed-off-by: Rafael Aquini <aquini@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Andi Kleen <andi@firstfloor.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* writeback: put unused inodes to LRU after writeback completionJan Kara2012-11-261-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 169ebd90131b ("writeback: Avoid iput() from flusher thread") removed iget-iput pair from inode writeback. As a side effect, inodes that are dirty during iput_final() call won't be ever added to inode LRU (iput_final() doesn't add dirty inodes to LRU and later when the inode is cleaned there's noone to add the inode there). Thus inodes are effectively unreclaimable until someone looks them up again. The practical effect of this bug is limited by the fact that inodes are pinned by a dentry for long enough that the inode gets cleaned. But still the bug can have nasty consequences leading up to OOM conditions under certain circumstances. Following can easily reproduce the problem: for (( i = 0; i < 1000; i++ )); do mkdir $i for (( j = 0; j < 1000; j++ )); do touch $i/$j echo 2 > /proc/sys/vm/drop_caches done done then one needs to run 'sync; ls -lR' to make inodes reclaimable again. We fix the issue by inserting unused clean inodes into the LRU after writeback finishes in inode_sync_complete(). Signed-off-by: Jan Kara <jack@suse.cz> Reported-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: <stable@vger.kernel.org> [3.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: replace vma prio_tree with an interval treeMichel Lespinasse2012-10-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | Implement an interval tree as a replacement for the VMA prio_tree. The algorithms are similar to lib/interval_tree.c; however that code can't be directly reused as the interval endpoints are not explicitly stored in the VMA. So instead, the common algorithm is moved into a template and the details (node type, how to get interval endpoints from the node, etc) are filled in using the C preprocessor. Once the interval tree functions are available, using them as a replacement to the VMA prio tree is a relatively simple, mechanical job. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.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 Torvalds2012-08-011-4/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
| * fs: Skip atime update on frozen filesystemJan Kara2012-07-311-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is unexpected to block reading of frozen filesystem because of atime update. Also handling blocking on frozen filesystem because of atime update would make locking more complex than it already is. So just skip atime update when filesystem is frozen like we skip it when filesystem is remounted read-only. BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * fs: Add freezing handling to mnt_want_write() / mnt_drop_write()Jan Kara2012-07-311-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most of places where we want freeze protection coincides with the places where we also have remount-ro protection. So make mnt_want_write() and mnt_drop_write() (and their _file alternative) prevent freezing as well. For the few cases that are really interested only in remount-ro protection provide new function variants. BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of ↵Linus Torvalds2012-07-261-0/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull large btrfs update from Chris Mason: "This pull request is very large, and the two main features in here have been under testing/devel for quite a while. We have subvolume quotas from the strato developers. This enables full tracking of how many blocks are allocated to each subvolume (and all snapshots) and you can set limits on a per-subvolume basis. You can also create quota groups and toss multiple subvolumes into a big group. It's everything you need to be a web hosting company and give each user their own subvolume. The userland side of the quotas is being refreshed, they'll send out details on where to grab it soon. Next is the kernel side of btrfs send/receive from Alexander Block. This leverages the same infrastructure as the quota code to figure out relationships between blocks and their owners. It can then compute the difference between two snapshots and sends the diffs in a neutral format into userland. The basic model: create a snapshot send that snapshot as the initial backup make changes create a second snapshot send the incremental as a backup delete the first snapshot (use the second snapshot for the next incremental) The receive portion is all in userland, and in the 'next' branch of my btrfs-progs repo. There's still some work to do in terms of optimizing the send side from kernel to userland. The really important part is figuring out how two snapshots are different, and this is where we are concentrating right now. The initial send of a dataset is a little slower than tar, but the incremental sends are dramatically faster than what rsync can do. On top of all of that, we have a nice queue of fixes, cleanups and optimizations." Fix up trivial modify/del conflict in fs/btrfs/ioctl.c Also fix up semantic conflict in fs/btrfs/send.c: the interface to dentry_open() changed in commit 765927b2d508 ("switch dentry_open() to struct path, make it grab references itself"), and since it now grabs whatever references it needs, we should no longer do the mntget() on the mnt (and we need to dput() the dentry reference we took). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (65 commits) Btrfs: uninit variable fixes in send/receive Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive Btrfs: add btrfs_compare_trees function Btrfs: introduce subvol uuids and times Btrfs: make iref_to_path non static Btrfs: add a barrier before a waitqueue_active check Btrfs: call the ordered free operation without any locks held Btrfs: Check INCOMPAT flags on remount and add helper function Btrfs: add helper for tree enumeration btrfs: allow cross-subvolume file clone Btrfs: improve multi-thread buffer read Btrfs: make btrfs's allocation smoothly with preallocation Btrfs: lock the transition from dirty to writeback for an eb Btrfs: fix potential race in extent buffer freeing Btrfs: don't return true in releasepage unless we actually freed the eb Btrfs: suppress printk() if all device I/O stats are zero Btrfs: remove unwanted printk() for btrfs device I/O stats Btrfs: rewrite BTRFS_SETGET_FUNCS Btrfs: zero unused bytes in inode item Btrfs: kill free_space pointer from inode structure ... Conflicts: fs/btrfs/ioctl.c
| * Btrfs: don't update atime on RO subvolumesAlexander Block2012-07-231-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | Before the update_time inode operation was indroduced, it was not possible to prevent updates of atime on RO subvolumes. VFS was only able to check for RO on the mount, but did not know anything about btrfs subvolumes. btrfs_update_time does now check if the root is RO and skip updating of times. Signed-off-by: Alexander Block <ablock84@googlemail.com>
* | vfs: switch i_dentry/d_alias to hlistAl Viro2012-07-141-1/+1
|/ | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-06-011-18/+106
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * fs: introduce inode operation ->update_timeJosef Bacik2012-06-011-16/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Btrfs has to make sure we have space to allocate new blocks in order to modify the inode, so updating time can fail. We've gotten around this by having our own file_update_time but this is kind of a pain, and Christoph has indicated he would like to make xfs do something different with atime updates. So introduce ->update_time, where we will deal with i_version an a/m/c time updates and indicate which changes need to be made. The normal version just does what it has always done, updates the time and marks the inode dirty, and then filesystems can choose to do something different. I've gone through all of the users of file_update_time and made them check for errors with the exception of the fault code since it's complicated and I wasn't quite sure what to do there, also Jan is going to be pushing the file time updates into page_mkwrite for those who have it so that should satisfy btrfs and make it not a big deal to check the file_update_time() return code in the generic fault path. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
| * fs: move file_remove_suid() to fs/inode.cCong Wang2012-05-301-0/+65
| | | | | | | | | | | | | | | | | | file_remove_suid() is a generic function operates on struct file, it almost has no relations with file mapping, so move it to fs/inode.c. Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * fs: fix inode.c kernel-doc warningsRandy Dunlap2012-05-291-2/+1
| | | | | | | | | | | | | | | | | | | | | | Fix kernel-doc warnings in fs/inode.c: Warning(fs/inode.c:1493): No description found for parameter 'path' Warning(fs/inode.c:1493): Excess function parameter 'mnt' description in 'touch_atime' Warning(fs/inode.c:1493): Excess function parameter 'dentry' description in 'touch_atime' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | NFS: Ensure that setattr and getattr wait for O_DIRECT write completionTrond Myklebust2012-05-311-0/+47
|/ | | | | | | | | | | | Use the same mechanism as the block devices are using, but move the helper functions from fs/direct-io.c into fs/inode.c to remove the dependency on CONFIG_BLOCK. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Fred Isaman <iisaman@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linuxLinus Torvalds2012-05-281-4/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * writeback: Avoid iput() from flusher threadJan Kara2012-05-061-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doing iput() from flusher thread (writeback_sb_inodes()) can create problems because iput() can do a lot of work - for example truncate the inode if it's the last iput on unlinked file. Some filesystems depend on flusher thread progressing (e.g. because they need to flush delay allocated blocks to reduce allocation uncertainty) and so flusher thread doing truncate creates interesting dependencies and possibilities for deadlocks. We get rid of iput() in flusher thread by using the fact that I_SYNC inode flag effectively pins the inode in memory. So if we take care to either hold i_lock or have I_SYNC set, we can get away without taking inode reference in writeback_sb_inodes(). As a side effect of these changes, we also fix possible use-after-free in wb_writeback() because inode_wait_for_writeback() call could try to reacquire i_lock on the inode that was already free. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
| * vfs: Rename end_writeback() to clear_inode()Jan Kara2012-05-061-3/+3
| | | | | | | | | | | | | | | | | | 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>
| * vfs: Move waiting for inode writeback from end_writeback() to evict_inode()Jan Kara2012-05-061-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, I_SYNC can never be set when evict_inode() (and thus end_writeback()) is called because flusher thread holds inode reference while inode is under writeback. As a result inode_sync_wait() in those places currently does nothing. However that is going to change and unveils problems with calling inode_sync_wait() from end_writeback(). Several filesystems call end_writeback() after they have deleted the inode (btrfs, gfs2, ...) and other filesystems (ext3, ext4, reiserfs, ...) can deadlock when waiting for I_SYNC because they call end_writeback() from within a transaction. To avoid these issues, we move inode_sync_wait() into evict_inode() before calling ->evict_inode(). That way we preserve the current property that ->evict_inode() and writeback never run in parallel and all filesystems are safe. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2012-05-241-0/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more networking updates from David Miller: "Ok, everything from here on out will be bug fixes." 1) One final sync of wireless and bluetooth stuff from John Linville. These changes have all been in his tree for more than a week, and therefore have had the necessary -next exposure. John was just away on a trip and didn't have a change to send the pull request until a day or two ago. 2) Put back some defines in user exposed header file areas that were removed during the tokenring purge. From Stephen Hemminger and Paul Gortmaker. 3) A bug fix for UDP hash table allocation got lost in the pile due to one of those "you got it.. no I've got it.." situations. :-) From Tim Bird. 4) SKB coalescing in TCP needs to have stricter checks, otherwise we'll try to coalesce overlapping frags and crash. Fix from Eric Dumazet. 5) RCU routing table lookups can race with free_fib_info(), causing crashes when we deref the device pointers in the route. Fix by releasing the net device in the RCU callback. From Yanmin Zhang. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (293 commits) tcp: take care of overlaps in tcp_try_coalesce() ipv4: fix the rcu race between free_fib_info and ip_route_output_slow mm: add a low limit to alloc_large_system_hash ipx: restore token ring define to include/linux/ipx.h if: restore token ring ARP type to header xen: do not disable netfront in dom0 phy/micrel: Fix ID of KSZ9021 mISDN: Add X-Tensions USB ISDN TA XC-525 gianfar:don't add FCB length to hard_header_len Bluetooth: Report proper error number in disconnection Bluetooth: Create flags for bt_sk() Bluetooth: report the right security level in getsockopt Bluetooth: Lock the L2CAP channel when sending Bluetooth: Restore locking semantics when looking up L2CAP channels Bluetooth: Fix a redundant and problematic incoming MTU check Bluetooth: Add support for Foxconn/Hon Hai AR5BBU22 0489:E03C Bluetooth: Fix EIR data generation for mgmt_device_found Bluetooth: Fix Inquiry with RSSI event mask Bluetooth: improve readability of l2cap_seq_list code Bluetooth: Fix skb length calculation ...
| * | mm: add a low limit to alloc_large_system_hashTim Bird2012-05-241-0/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UDP stack needs a minimum hash size value for proper operation and also uses alloc_large_system_hash() for proper NUMA distribution of its hash tables and automatic sizing depending on available system memory. On some low memory situations, udp_table_init() must ignore the alloc_large_system_hash() result and reallocs a bigger memory area. As we cannot easily free old hash table, we leak it and kmemleak can issue a warning. This patch adds a low limit parameter to alloc_large_system_hash() to solve this problem. We then specify UDP_HTABLE_SIZE_MIN for UDP/UDPLite hash table allocation. Reported-by: Mark Asselstine <mark.asselstine@windriver.com> Reported-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | userns: Store uid and gid types in vfs structures with kuid_t and kgid_t typesEric W. Biederman2012-05-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The conversion of all of the users is not done yet there are too many to change in one go and leave the code reviewable. For now I change just the header and a few trivial users and rely on CONFIG_UIDGID_STRICT_TYPE_CHECKS not being set to ensure that the code will still compile during the transition. Helper functions i_uid_read, i_uid_write, i_gid_read, i_gid_write are added so that in most cases filesystems can avoid the complexities of multiple user namespaces and can concentrate on moving their raw numeric values into and out of the vfs data structures. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | userns: Replace the hard to write inode_userns with inode_capable.Eric W. Biederman2012-04-071-4/+2
|/ | | | | | | | | | | | | | | | | | | | | This represents a change in strategy of how to handle user namespaces. Instead of tagging everything explicitly with a user namespace and bulking up all of the comparisons of uids and gids in the kernel, all uids and gids in use will have a mapping to a flat kuid and kgid spaces respectively. This allows much more of the existing logic to be preserved and in general allows for faster code. In this new and improved world we allow someone to utiliize capabilities over an inode if the inodes owner mapps into the capabilities holders user namespace and the user has capabilities in their user namespace. Which is simple and efficient. Moving the fs uid comparisons to be comparisons in a flat kuid space follows in later patches, something that is only significant if you are using user namespaces. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* trim includes in inode.cAl Viro2012-03-201-11/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch touch_atime to struct pathAl Viro2012-03-201-2/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: turn generic_drop_inode() into static inlineAl Viro2012-03-201-11/+0
| | | | | | | | | Once upon a time it used to be much bigger, but these days there's no point whatsoever keeping it in fs/inode.c, especially since it's not even needed as initializer for ->drop_inode() - it's the default and leaving ->drop_inode NULL will do just as well. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* restore smp_mb() in unlock_new_inode()Al Viro2012-03-101-0/+1
| | | | | | wait_on_inode() doesn't have ->i_lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: Correctly set the dir i_mutex lockdep classTyler Hicks2012-03-101-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 9a7aa12f3911853a introduced additional logic around setting the i_mutex lockdep class for directory inodes. The idea was that some filesystems may want their own special lockdep class for different directory inodes and calling unlock_new_inode() should not clobber one of those special classes. I believe that the added conditional, around the *negated* return value of lockdep_match_class(), caused directory inodes to be placed in the wrong lockdep class. inode_init_always() sets the i_mutex lockdep class with i_mutex_key for all inodes. If the filesystem did not change the class during inode initialization, then the conditional mentioned above was false and the directory inode was incorrectly left in the non-directory lockdep class. If the filesystem did set a special lockdep class, then the conditional mentioned above was true and that class was clobbered with i_mutex_dir_key. This patch removes the negation from the conditional so that the i_mutex lockdep class is properly set for directory inodes. Special classes are preserved and directory inodes with unmodified classes are set with i_mutex_dir_key. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: fix panic in __d_lookup() with high dentry hashtable countsDimitri Sivanich2012-02-131-4/+4
| | | | | | | | | | | | | | When the number of dentry cache hash table entries gets too high (2147483648 entries), as happens by default on a 16TB system, use of a signed integer in the dcache_init() initialization loop prevents the dentry_hashtable from getting initialized, causing a panic in __d_lookup(). Fix this in dcache_init() and similar areas. Signed-off-by: Dimitri Sivanich <sivanich@sgi.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: remove printk from set_nlink()Miklos Szeredi2012-01-171-3/+0
| | | | | | | Don't log a message for set_nlink(0). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mm: account reaped page cache on inode cache pruningKonstantin Khlebnikov2012-01-101-0/+2
| | | | | | | | | | | Inode cache pruning indirectly reclaims page-cache by invalidating mapping pages. Let's account them into reclaim-state to notice this progress in memory reclaimer. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: count unlinked inodesMiklos Szeredi2012-01-061-0/+85
| | | | | | | | | | | | | | Add a new counter to the superblock that keeps track of unlinked but not yet deleted inodes. Do not WARN_ON if set_nlink is called with zero count, just do a ratelimited printk. This happens on xfs and probably other filesystems after an unclean shutdown when the filesystem reads inodes which already have zero i_nlink. Reported by Christoph Hellwig. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch inode_init_owner() to umode_tAl Viro2012-01-031-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: fix the stupidity with i_dentry in inode destructorsAl Viro2012-01-031-2/+1
| | | | | | | | | | 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>
* vfs: mnt_drop_write_file()Al Viro2012-01-031-1/+1
| | | | | | | new helper (wrapper around mnt_drop_write()) to be used in pair with mnt_want_write_file(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: protect i_nlinkMiklos Szeredi2011-11-021-1/+1
| | | | | | | | | Prevent direct modification of i_nlink by making it const and adding a non-const __i_nlink alias. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
* vfs: fix spinning prevention in prune_icache_sbChristoph Hellwig2011-10-281-1/+1
| | | | | | | | | We need to move the inode to the end of the list to actually make the spinning prevention explained in the comment above it work. With a plain list_move it will simply stay in place as we're always reclaiming from the head of the list. Signed-off-by: Christoph Hellwig <hch@lst.de>
* lockdep: Add helper function for dir vs file i_mutex annotationJosh Boyer2011-08-251-9/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Purely in-memory filesystems do not use the inode hash as the dcache tells us if an entry already exists. As a result, they do not call unlock_new_inode, and thus directory inodes do not get put into a different lockdep class for i_sem. We need the different lockdep classes, because the locking order for i_mutex is different for directory inodes and regular inodes. Directory inodes can do "readdir()", which takes i_mutex *before* possibly taking mm->mmap_sem (due to a page fault while copying the directory entry to user space). In contrast, regular inodes can be mmap'ed, which takes mm->mmap_sem before accessing i_mutex. The two cases can never happen for the same inode, so no real deadlock can occur, but without the different lockdep classes, lockdep cannot understand that. As a result, if CONFIG_DEBUG_LOCK_ALLOC is set, this can lead to false positives from lockdep like below: find/645 is trying to acquire lock: (&mm->mmap_sem){++++++}, at: [<ffffffff81109514>] might_fault+0x5c/0xac but task is already holding lock: (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffff81149f34>] vfs_readdir+0x5b/0xb4 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#15){+.+.+.}: [<ffffffff8108ac26>] lock_acquire+0xbf/0x103 [<ffffffff814db822>] __mutex_lock_common+0x4c/0x361 [<ffffffff814dbc46>] mutex_lock_nested+0x40/0x45 [<ffffffff811daa87>] hugetlbfs_file_mmap+0x82/0x110 [<ffffffff81111557>] mmap_region+0x258/0x432 [<ffffffff811119dd>] do_mmap_pgoff+0x2ac/0x306 [<ffffffff81111b4f>] sys_mmap_pgoff+0x118/0x16a [<ffffffff8100c858>] sys_mmap+0x22/0x24 [<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b -> #0 (&mm->mmap_sem){++++++}: [<ffffffff8108a4bc>] __lock_acquire+0xa1a/0xcf7 [<ffffffff8108ac26>] lock_acquire+0xbf/0x103 [<ffffffff81109541>] might_fault+0x89/0xac [<ffffffff81149cff>] filldir+0x6f/0xc7 [<ffffffff811586ea>] dcache_readdir+0x67/0x205 [<ffffffff81149f54>] vfs_readdir+0x7b/0xb4 [<ffffffff8114a073>] sys_getdents+0x7e/0xd1 [<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b This patch moves the directory vs file lockdep annotation into a helper function that can be called by in-memory filesystems and has hugetlbfs call it. Signed-off-by: Josh Boyer <jwboyer@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: optimize inode cache access patternsLinus Torvalds2011-08-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | The inode structure layout is largely random, and some of the vfs paths really do care. The path lookup in particular is already quite D$ intensive, and profiles show that accessing the 'inode->i_op->xyz' fields is quite costly. We already optimized the dcache to not unnecessarily load the d_op structure for members that are often NULL using the DCACHE_OP_xyz bits in dentry->d_flags, and this does something very similar for the inode ops that are used during pathname lookup. It also re-orders the fields so that the fields accessed by 'stat' are together at the beginning of the inode structure, and roughly in the order accessed. The effect of this seems to be in the 1-2% range for an empty kernel "make -j" run (which is fairly kernel-intensive, mostly in filename lookup), so it's visible. The numbers are fairly noisy, though, and likely depend a lot on exact microarchitecture. So there's more tuning to be done. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: avoid call to inode_lru_list_del() if possibleEric Dumazet2011-08-011-1/+2
| | | | | | | | | | | inode_lru_list_del() is expensive because of per superblock lru locking, while some inodes are not in lru list. Adding a check in iput_final() can speedup pipe/sockets workloads on SMP. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: avoid taking inode_hash_lock on pipes and socketsEric Dumazet2011-08-011-3/+3
| | | | | | | | | | Some inodes (pipes, sockets, ...) are not hashed, no need to take contended inode_hash_lock at dismantle time. nice speedup on SMP machines on socket intensive workloads. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: conditionally call inode_wb_list_del()Eric Dumazet2011-08-011-1/+3
| | | | | | | | | | | | | Some inodes (pipes, sockets, ...) are not in bdi writeback list. evict() can avoid calling inode_wb_list_del() and its expensive spinlock by checking inode i_wb_list being empty or not. At this point, no other cpu/user can concurrently manipulate this inode i_wb_list Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-07-261-9/+30
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: merge fchmod() and fchmodat() guts, kill ancient broken kludge xfs: fix misspelled S_IS...() xfs: get rid of open-coded S_ISREG(), etc. vfs: document locking requirements for d_move, __d_move and d_materialise_unique omfs: fix (mode & S_IFDIR) abuse btrfs: S_ISREG(mode) is not mode & S_IFREG... ima: fmode_t misspelled as mode_t... pci-label.c: size_t misspelled as mode_t jffs2: S_ISLNK(mode & S_IFMT) is pointless snd_msnd ->mode is fmode_t, not mode_t v9fs_iop_get_acl: get rid of unused variable vfs: dont chain pipe/anon/socket on superblock s_inodes list Documentation: Exporting: update description of d_splice_alias fs: add missing unlock in default_llseek()
| * vfs: dont chain pipe/anon/socket on superblock s_inodes listEric Dumazet2011-07-261-9/+30
| | | | | | | | | | | | | | | | | | | | | | | | Workloads using pipes and sockets hit inode_sb_list_lock contention. superblock s_inodes list is needed for quota, dirty, pagecache and fsnotify management. pipe/anon/socket fs are clearly not candidates for these. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of ↵Linus Torvalds2011-07-261-3/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wfg/writeback * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/writeback: (27 commits) mm: properly reflect task dirty limits in dirty_exceeded logic writeback: don't busy retry writeback on new/freeing inodes writeback: scale IO chunk size up to half device bandwidth writeback: trace global_dirty_state writeback: introduce max-pause and pass-good dirty limits writeback: introduce smoothed global dirty limit writeback: consolidate variable names in balance_dirty_pages() writeback: show bdi write bandwidth in debugfs writeback: bdi write bandwidth estimation writeback: account per-bdi accumulated written pages writeback: make writeback_control.nr_to_write straight writeback: skip tmpfs early in balance_dirty_pages_ratelimited_nr() writeback: trace event writeback_queue_io writeback: trace event writeback_single_inode writeback: remove .nonblocking and .encountered_congestion writeback: remove writeback_control.more_io writeback: skip balance_dirty_pages() for in-memory fs writeback: add bdi_dirty_limit() kernel-doc writeback: avoid extra sync work at enqueue time writeback: elevate queue_io() into wb_writeback() ... Fix up trivial conflicts in fs/fs-writeback.c and mm/filemap.c
| * writeback: split inode_wb_list_lock into bdi_writeback.list_lockChristoph Hellwig2011-06-081-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split the global inode_wb_list_lock into a per-bdi_writeback list_lock, as it's currently the most contended lock in the system for metadata heavy workloads. It won't help for single-filesystem workloads for which we'll need the I/O-less balance_dirty_pages, but at least we can dedicate a cpu to spinning on each bdi now for larger systems. Based on earlier patches from Nick Piggin and Dave Chinner. It reduces lock contentions to 1/4 in this test case: 10 HDD JBOD, 100 dd on each disk, XFS, 6GB ram lock_stat version 0.3 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- class name con-bounces contentions waittime-min waittime-max waittime-total acq-bounces acquisitions holdtime-min holdtime-max holdtime-total ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- vanilla 2.6.39-rc3: inode_wb_list_lock: 42590 44433 0.12 147.74 144127.35 252274 886792 0.08 121.34 917211.23 ------------------ inode_wb_list_lock 2 [<ffffffff81165da5>] bdev_inode_switch_bdi+0x29/0x85 inode_wb_list_lock 34 [<ffffffff8115bd0b>] inode_wb_list_del+0x22/0x49 inode_wb_list_lock 12893 [<ffffffff8115bb53>] __mark_inode_dirty+0x170/0x1d0 inode_wb_list_lock 10702 [<ffffffff8115afef>] writeback_single_inode+0x16d/0x20a ------------------ inode_wb_list_lock 2 [<ffffffff81165da5>] bdev_inode_switch_bdi+0x29/0x85 inode_wb_list_lock 19 [<ffffffff8115bd0b>] inode_wb_list_del+0x22/0x49 inode_wb_list_lock 5550 [<ffffffff8115bb53>] __mark_inode_dirty+0x170/0x1d0 inode_wb_list_lock 8511 [<ffffffff8115b4ad>] writeback_sb_inodes+0x10f/0x157 2.6.39-rc3 + patch: &(&wb->list_lock)->rlock: 11383 11657 0.14 151.69 40429.51 90825 527918 0.11 145.90 556843.37 ------------------------ &(&wb->list_lock)->rlock 10 [<ffffffff8115b189>] inode_wb_list_del+0x5f/0x86 &(&wb->list_lock)->rlock 1493 [<ffffffff8115b1ed>] writeback_inodes_wb+0x3d/0x150 &(&wb->list_lock)->rlock 3652 [<ffffffff8115a8e9>] writeback_sb_inodes+0x123/0x16f &(&wb->list_lock)->rlock 1412 [<ffffffff8115a38e>] writeback_single_inode+0x17f/0x223 ------------------------ &(&wb->list_lock)->rlock 3 [<ffffffff8110b5af>] bdi_lock_two+0x46/0x4b &(&wb->list_lock)->rlock 6 [<ffffffff8115b189>] inode_wb_list_del+0x5f/0x86 &(&wb->list_lock)->rlock 2061 [<ffffffff8115af97>] __mark_inode_dirty+0x173/0x1cf &(&wb->list_lock)->rlock 2629 [<ffffffff8115a8e9>] writeback_sb_inodes+0x123/0x16f hughd@google.com: fix recursive lock when bdi_lock_two() is called with new the same as old akpm@linux-foundation.org: cleanup bdev_inode_switch_bdi() comment Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
* | fs: kill i_alloc_semChristoph Hellwig2011-07-201-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | i_alloc_sem is a rather special rw_semaphore. It's the last one that may be released by a non-owner, and it's write side is always mirrored by real exclusion. It's intended use it to wait for all pending direct I/O requests to finish before starting a truncate. Replace it with a hand-grown construct: - exclusion for truncates is already guaranteed by i_mutex, so it can simply fall way - the reader side is replaced by an i_dio_count member in struct inode that counts the number of pending direct I/O requests. Truncate can't proceed as long as it's non-zero - when i_dio_count reaches non-zero we wake up a pending truncate using wake_up_bit on a new bit in i_flags - new references to i_dio_count can't appear while we are waiting for it to read zero because the direct I/O count always needs i_mutex (or an equivalent like XFS's i_iolock) for starting a new operation. This scheme is much simpler, and saves the space of a spinlock_t and a struct list_head in struct inode (typically 160 bits on a non-debug 64-bit system). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | inode: remove iprune_semDave Chinner2011-07-201-21/+0
| | | | | | | | | | | | | | | | | | | | Now that we have per-sb shrinkers with a lifecycle that is a subset of the superblock lifecycle and can reliably detect a filesystem being unmounted, there is not longer any race condition for the iprune_sem to protect against. Hence we can remove it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | superblock: introduce per-sb cache shrinker infrastructureDave Chinner2011-07-201-108/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With context based shrinkers, we can implement a per-superblock shrinker that shrinks the caches attached to the superblock. We currently have global shrinkers for the inode and dentry caches that split up into per-superblock operations via a coarse proportioning method that does not batch very well. The global shrinkers also have a dependency - dentries pin inodes - so we have to be very careful about how we register the global shrinkers so that the implicit call order is always correct. With a per-sb shrinker callout, we can encode this dependency directly into the per-sb shrinker, hence avoiding the need for strictly ordering shrinker registrations. We also have no need for any proportioning code for the shrinker subsystem already provides this functionality across all shrinkers. Allowing the shrinker to operate on a single superblock at a time means that we do less superblock list traversals and locking and reclaim should batch more effectively. This should result in less CPU overhead for reclaim and potentially faster reclaim of items from each filesystem. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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