summaryrefslogtreecommitdiff
path: root/fs/locks.c
AgeCommit message (Collapse)AuthorFilesLines
2019-03-25locks: wake any locks blocked on request before deadlock checkJeff Layton1-0/+5
Andreas reported that he was seeing the tdbtorture test fail in some cases with -EDEADLCK when it wasn't before. Some debugging showed that deadlock detection was sometimes discovering the caller's lock request itself in a dependency chain. While we remove the request from the blocked_lock_hash prior to reattempting to acquire it, any locks that are blocked on that request will still be present in the hash and will still have their fl_blocker pointer set to the current request. This causes posix_locks_deadlock to find a deadlock dependency chain when it shouldn't, as a lock request cannot block itself. We are going to end up waking all of those blocked locks anyway when we go to reinsert the request back into the blocked_lock_hash, so just do it prior to checking for deadlocks. This ensures that any lock blocked on the current request will no longer be part of any blocked request chain. URL: https://bugzilla.kernel.org/show_bug.cgi?id=202975 Fixes: 5946c4319ebb ("fs/locks: allow a lock request to block other requests.") Cc: stable@vger.kernel.org Reported-by: Andreas Schneider <asn@redhat.com> Signed-off-by: Neil Brown <neilb@suse.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-02-28locking/percpu-rwsem: Remove preempt_disable variantsPeter Zijlstra1-16/+16
Effective revert commit: 87709e28dc7c ("fs/locks: Use percpu_down_read_preempt_disable()") This is causing major pain for PREEMPT_RT. Sebastian did a lot of lockperf runs on 2 and 4 node machines with all preemption modes (PREEMPT=n should be an obvious NOP for this patch and thus serves as a good control) and no results showed significance over 2-sigma (the PREEMPT=n results were almost empty at 1-sigma). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-03locks: fix error in locks_move_blocks()NeilBrown1-1/+1
After moving all requests from fl->fl_blocked_requests to new->fl_blocked_requests it is nonsensical to do anything to all the remaining elements, there aren't any. This should do something to all the requests that have been moved. For simplicity, it does it to all requests in the target list. Setting "f->fl_blocker = new" to all members of new->fl_blocked_requests is "obviously correct" as it preserves the invariant of the linkage among requests. Reported-by: syzbot+239d99847eb49ecb3899@syzkaller.appspotmail.com Fixes: 5946c4319ebb ("fs/locks: allow a lock request to block other requests.") Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-17locks: Use inode_is_open_for_writeNikolay Borisov1-1/+1
Use the aptly named function rather than open coding it. No functional changes. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07fs/locks: remove unnecessary white space.NeilBrown1-21/+12
- spaces before tabs, - spaces at the end of lines, - multiple blank lines, - blank lines before EXPORT_SYMBOL, can all go. Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07fs/locks: merge posix_unblock_lock() and locks_delete_block()NeilBrown1-24/+14
posix_unblock_lock() is not specific to posix locks, and behaves nearly identically to locks_delete_block() - the former returning a status while the later doesn't. So discard posix_unblock_lock() and use locks_delete_block() instead, after giving that function an appropriate return value. Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07fs/locks: create a tree of dependent requests.NeilBrown1-6/+63
When we find an existing lock which conflicts with a request, and the request wants to wait, we currently add the request to a list. When the lock is removed, the whole list is woken. This can cause the thundering-herd problem. To reduce the problem, we make use of the (new) fact that a pending request can itself have a list of blocked requests. When we find a conflict, we look through the existing blocked requests. If any one of them blocks the new request, the new request is attached below that request, otherwise it is added to the list of blocked requests, which are now known to be mutually non-conflicting. This way, when the lock is released, only a set of non-conflicting locks will be woken, the rest can stay asleep. If the lock request cannot be granted and the request needs to be requeued, all the other requests it blocks will then be woken To make this more concrete: If you have a many-core machine, and have many threads all wanting to briefly lock a give file (udev is known to do this), you can get quite poor performance. When one thread releases a lock, it wakes up all other threads that are waiting (classic thundering-herd) - one will get the lock and the others go to sleep. When you have few cores, this is not very noticeable: by the time the 4th or 5th thread gets enough CPU time to try to claim the lock, the earlier threads have claimed it, done what was needed, and released. So with few cores, many of the threads don't end up contending. With 50+ cores, lost of threads can get the CPU at the same time, and the contention can easily be measured. This patchset creates a tree of pending lock requests in which siblings don't conflict and each lock request does conflict with its parent. When a lock is released, only requests which don't conflict with each other a woken. Testing shows that lock-acquisitions-per-second is now fairly stable even as the number of contending process goes to 1000. Without this patch, locks-per-second drops off steeply after a few 10s of processes. There is a small cost to this extra complexity. At 20 processes running a particular test on 72 cores, the lock acquisitions per second drops from 1.8 million to 1.4 million with this patch. For 100 processes, this patch still provides 1.4 million while without this patch there are about 700,000. Reported-and-tested-by: Martin Wilck <mwilck@suse.de> Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07fs/locks: change all *_conflict() functions to return bool.NeilBrown1-12/+15
posix_locks_conflict() and flock_locks_conflict() both return int. leases_conflict() returns bool. This inconsistency will cause problems for the next patch if not fixed. So change posix_locks_conflict() and flock_locks_conflict() to return bool. Also change the locks_conflict() helper. And convert some return (foo); to return foo; Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-12-07fs/locks: always delete_block after waiting.NeilBrown1-16/+24
Now that requests can block other requests, we need to be careful to always clean up those blocked requests. Any time that we wait for a request, we might have other requests attached, and when we stop waiting, we must clean them up. If the lock was granted, the requests might have been moved to the new lock, though when merged with a pre-exiting lock, this might not happen. In all cases we don't want blocked locks to remain attached, so we remove them to be safe. Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Tested-by: syzbot+a4a3d526b4157113ec6a@syzkaller.appspotmail.com Tested-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-11-30fs/locks: allow a lock request to block other requests.NeilBrown1-6/+37
Currently, a lock can block pending requests, but all pending requests are equal. If lots of pending requests are mutually exclusive, this means they will all be woken up and all but one will fail. This can hurt performance. So we will allow pending requests to block other requests. Only the first request will be woken, and it will wake the others. This patch doesn't implement this fully, but prepares the way. - It acknowledges that a request might be blocking other requests, and when the request is converted to a lock, those blocked requests are moved across. - When a request is requeued or discarded, all blocked requests are woken. - When deadlock-detection looks for the lock which blocks a given request, we follow the chain of ->fl_blocker all the way to the top. Tested-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-11-30fs/locks: use properly initialized file_lock when unlocking.NeilBrown1-14/+14
Both locks_remove_posix() and locks_remove_flock() use a struct file_lock without calling locks_init_lock() on it. This means the various list_heads are not initialized, which will become a problem with a later patch. So change them both to initialize properly. For flock locks, this involves using flock_make_lock(), and changing it to allow a file_lock to be passed in, so memory allocation isn't always needed. Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-11-30fs/locks: split out __locks_wake_up_blocks().NeilBrown1-11/+16
This functionality will be useful in future patches, so split it out from locks_wake_up_blocks(). Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-11-30fs/locks: rename some lists and pointers.NeilBrown1-28/+31
struct file lock contains an 'fl_next' pointer which is used to point to the lock that this request is blocked waiting for. So rename it to fl_blocker. The fl_blocked list_head in an active lock is the head of a list of blocked requests. In a request it is a node in that list. These are two distinct uses, so replace with two list_heads with different names. fl_blocked_requests is the head of a list of blocked requests fl_blocked_member is a node in a member of that list. The two different list_heads are never used at the same time, but that will change in a future patch. Note that a tracepoint is changed to report fl_blocker instead of fl_next. Signed-off-by: NeilBrown <neilb@suse.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-08-22Merge tag 'ovl-update-4.19' of ↵Linus Torvalds1-13/+7
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "This contains two new features: - Stack file operations: this allows removal of several hacks from the VFS, proper interaction of read-only open files with copy-up, possibility to implement fs modifying ioctls properly, and others. - Metadata only copy-up: when file is on lower layer and only metadata is modified (except size) then only copy up the metadata and continue to use the data from the lower file" * tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (66 commits) ovl: Enable metadata only feature ovl: Do not do metacopy only for ioctl modifying file attr ovl: Do not do metadata only copy-up for truncate operation ovl: add helper to force data copy-up ovl: Check redirect on index as well ovl: Set redirect on upper inode when it is linked ovl: Set redirect on metacopy files upon rename ovl: Do not set dentry type ORIGIN for broken hardlinks ovl: Add an inode flag OVL_CONST_INO ovl: Treat metacopy dentries as type OVL_PATH_MERGE ovl: Check redirects for metacopy files ovl: Move some dir related ovl_lookup_single() code in else block ovl: Do not expose metacopy only dentry from d_real() ovl: Open file with data except for the case of fsync ovl: Add helper ovl_inode_realdata() ovl: Store lower data inode in ovl_inode ovl: Fix ovl_getattr() to get number of blocks from lower ovl: Add helper ovl_dentry_lowerdata() to get lower data dentry ovl: Copy up meta inode data from lowest data inode ovl: Modify ovl_lookup() and friends to lookup metacopy dentry ...
2018-08-21Merge branch 'siginfo-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull core signal handling updates from Eric Biederman: "It was observed that a periodic timer in combination with a sufficiently expensive fork could prevent fork from every completing. This contains the changes to remove the need for that restart. This set of changes is split into several parts: - The first part makes PIDTYPE_TGID a proper pid type instead something only for very special cases. The part starts using PIDTYPE_TGID enough so that in __send_signal where signals are actually delivered we know if the signal is being sent to a a group of processes or just a single process. - With that prep work out of the way the logic in fork is modified so that fork logically makes signals received while it is running appear to be received after the fork completes" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits) signal: Don't send signals to tasks that don't exist signal: Don't restart fork when signals come in. fork: Have new threads join on-going signal group stops fork: Skip setting TIF_SIGPENDING in ptrace_init_task signal: Add calculate_sigpending() fork: Unconditionally exit if a fatal signal is pending fork: Move and describe why the code examines PIDNS_ADDING signal: Push pid type down into complete_signal. signal: Push pid type down into __send_signal signal: Push pid type down into send_signal signal: Pass pid type into do_send_sig_info signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task signal: Pass pid type into group_send_sig_info signal: Pass pid and pid type into send_sigqueue posix-timers: Noralize good_sigevent signal: Use PIDTYPE_TGID to clearly store where file signals will be sent pid: Implement PIDTYPE_TGID pids: Move the pgrp and session pid pointers from task_struct to signal_struct kvm: Don't open code task_pid in kvm_vcpu_ioctl pids: Compute task_tgid using signal->leader_pid ...
2018-08-14Merge tag 'locks-v4.19-1' of ↵Linus Torvalds1-9/+11
git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux Pull file locking updates from Jeff Layton: "Just a couple of patches from Konstantin to fix /proc/locks when the process that set the lock has exited, and a new tracepoint for the flock() codepath. Also threw in mailmap entries for my addresses and a comment cleanup" * tag 'locks-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: locks: remove misleading obsolete comment mailmap: remap some of my email addresses to kernel.org address locks: add tracepoint in flock codepath fs/lock: show locks taken by processes from another pidns fs/lock: skip lock owner pid translation in case we are in init_pid_ns
2018-08-08locks: remove misleading obsolete commentJeff Layton1-4/+0
The spinlock handling in this file has changed significantly since this comment was written, and the file_lock_lock is no more. In addition, this overall comment no longer applies. Deleting an entry now requires both locks. Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-08-06locks: add tracepoint in flock codepathJeff Layton1-0/+1
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2018-07-21signal: Use PIDTYPE_TGID to clearly store where file signals will be sentEric W. Biederman1-1/+1
When f_setown is called a pid and a pid type are stored. Replace the use of PIDTYPE_PID with PIDTYPE_TGID as PIDTYPE_TGID goes to the entire thread group. Replace the use of PIDTYPE_MAX with PIDTYPE_PID as PIDTYPE_PID now is only for a thread. Update the users of __f_setown to use PIDTYPE_TGID instead of PIDTYPE_PID. For now the code continues to capture task_pid (when task_tgid would really be appropriate), and iterate on PIDTYPE_PID (even when type == PIDTYPE_TGID) out of an abundance of caution to preserve existing behavior. Oleg Nesterov suggested using the test to ensure we use PIDTYPE_PID for tgid lookup also be used to avoid taking the tasklist lock. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-18Partially revert "locks: fix file locking on overlayfs"Miklos Szeredi1-11/+6
This partially reverts commit c568d68341be7030f5647def68851e469b21ca11. Overlayfs files will now automatically get the correct locks, no need to hack overlay support in VFS. It is a partial revert, because it leaves the locks_inode() calls in place and defines locks_inode() to file_inode(). We could revert those as well, but it would be unnecessary code churn and it makes sense to document that we are getting the inode for locking purposes. Don't revert MS_NOREMOTELOCK yet since that has been part of the userspace API for some time (though not in a useful way). Will try to remove internal flags later when the dust around the new mount API settles. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: Jeff Layton <jlayton@kernel.org>
2018-07-18Revert "vfs: do get_write_access() on upper layer of overlayfs"Miklos Szeredi1-2/+1
This reverts commit 4d0c5ba2ff79ef9f5188998b29fd28fcb05f3667. We now get write access on both overlay and underlying layers so this patch is no longer needed for correct operation. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-06-15Merge tag 'vfs-timespec64' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground Pull inode timestamps conversion to timespec64 from Arnd Bergmann: "This is a late set of changes from Deepa Dinamani doing an automated treewide conversion of the inode and iattr structures from 'timespec' to 'timespec64', to push the conversion from the VFS layer into the individual file systems. As Deepa writes: 'The series aims to switch vfs timestamps to use struct timespec64. Currently vfs uses struct timespec, which is not y2038 safe. The series involves the following: 1. Add vfs helper functions for supporting struct timepec64 timestamps. 2. Cast prints of vfs timestamps to avoid warnings after the switch. 3. Simplify code using vfs timestamps so that the actual replacement becomes easy. 4. Convert vfs timestamps to use struct timespec64 using a script. This is a flag day patch. Next steps: 1. Convert APIs that can handle timespec64, instead of converting timestamps at the boundaries. 2. Update internal data structures to avoid timestamp conversions' Thomas Gleixner adds: 'I think there is no point to drag that out for the next merge window. The whole thing needs to be done in one go for the core changes which means that you're going to play that catchup game forever. Let's get over with it towards the end of the merge window'" * tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground: pstore: Remove bogus format string definition vfs: change inode times to use struct timespec64 pstore: Convert internal records to timespec64 udf: Simplify calls to udf_disk_stamp_to_time fs: nfs: get rid of memcpys for inode times ceph: make inode time prints to be long long lustre: Use long long type to print inode time fs: add timespec64_truncate()
2018-06-14fs/lock: show locks taken by processes from another pidnsKonstantin Khorenko1-5/+3
Currently if we face a lock taken by a process invisible in the current pidns we skip the lock completely, but this 1) makes the output not that nice (root@vz7)/: cat /proc/${PID_A2}/fdinfo/3 pos: 4 flags: 02100002 mnt_id: 257 lock: (root@vz7)/: 2) makes it more difficult to debug issues with leaked flocks if you get error on lock, but don't see any locks in /proc/$id/fdinfo/$file Let's show information about such locks again as previously, but show zero in the owner pid field. After the patch: =============== (root@vz7)/:cat /proc/${PID_A2}/fdinfo/3 pos: 4 flags: 02100002 mnt_id: 295 lock: 1: FLOCK ADVISORY WRITE 0 b6:f8a61:529946 0 EOF Fixes: 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks") Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com> Acked-by: Andrey Vagin <avagin@openvz.org> Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-06-14fs/lock: skip lock owner pid translation in case we are in init_pid_nsKonstantin Khorenko1-0/+7
If the flock owner process is dead and its pid has been already freed, pid translation won't work, but we still want to show flock owner pid number when expecting /proc/$PID/fdinfo/$FD in init pidns. Reproducer: process A process A1 process A2 fork()---------> exit() open() flock() fork()---------> exit() sleep() Before the patch: ================ (root@vz7)/: cat /proc/${PID_A2}/fdinfo/3 pos: 4 flags: 02100002 mnt_id: 257 lock: (root@vz7)/: After the patch: =============== (root@vz7)/:cat /proc/${PID_A2}/fdinfo/3 pos: 4 flags: 02100002 mnt_id: 295 lock: 1: FLOCK ADVISORY WRITE ${PID_A1} b6:f8a61:529946 0 EOF Fixes: 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks") Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com> Acked-by: Andrey Vagin <avagin@openvz.org> Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-06-06vfs: change inode times to use struct timespec64Deepa Dinamani1-1/+1
struct timespec is not y2038 safe. Transition vfs to use y2038 safe struct timespec64 instead. The change was made with the help of the following cocinelle script. This catches about 80% of the changes. All the header file and logic changes are included in the first 5 rules. The rest are trivial substitutions. I avoid changing any of the function signatures or any other filesystem specific data structures to keep the patch simple for review. The script can be a little shorter by combining different cases. But, this version was sufficient for my usecase. virtual patch @ depends on patch @ identifier now; @@ - struct timespec + struct timespec64 current_time ( ... ) { - struct timespec now = current_kernel_time(); + struct timespec64 now = current_kernel_time64(); ... - return timespec_trunc( + return timespec64_trunc( ... ); } @ depends on patch @ identifier xtime; @@ struct \( iattr \| inode \| kstat \) { ... - struct timespec xtime; + struct timespec64 xtime; ... } @ depends on patch @ identifier t; @@ struct inode_operations { ... int (*update_time) (..., - struct timespec t, + struct timespec64 t, ...); ... } @ depends on patch @ identifier t; identifier fn_update_time =~ "update_time$"; @@ fn_update_time (..., - struct timespec *t, + struct timespec64 *t, ...) { ... } @ depends on patch @ identifier t; @@ lease_get_mtime( ... , - struct timespec *t + struct timespec64 *t ) { ... } @te depends on patch forall@ identifier ts; local idexpression struct inode *inode_node; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn_update_time =~ "update_time$"; identifier fn; expression e, E3; local idexpression struct inode *node1; local idexpression struct inode *node2; local idexpression struct iattr *attr1; local idexpression struct iattr *attr2; local idexpression struct iattr attr; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; @@ ( ( - struct timespec ts; + struct timespec64 ts; | - struct timespec ts = current_time(inode_node); + struct timespec64 ts = current_time(inode_node); ) <+... when != ts ( - timespec_equal(&inode_node->i_xtime, &ts) + timespec64_equal(&inode_node->i_xtime, &ts) | - timespec_equal(&ts, &inode_node->i_xtime) + timespec64_equal(&ts, &inode_node->i_xtime) | - timespec_compare(&inode_node->i_xtime, &ts) + timespec64_compare(&inode_node->i_xtime, &ts) | - timespec_compare(&ts, &inode_node->i_xtime) + timespec64_compare(&ts, &inode_node->i_xtime) | ts = current_time(e) | fn_update_time(..., &ts,...) | inode_node->i_xtime = ts | node1->i_xtime = ts | ts = inode_node->i_xtime | <+... attr1->ia_xtime ...+> = ts | ts = attr1->ia_xtime | ts.tv_sec | ts.tv_nsec | btrfs_set_stack_timespec_sec(..., ts.tv_sec) | btrfs_set_stack_timespec_nsec(..., ts.tv_nsec) | - ts = timespec64_to_timespec( + ts = ... -) | - ts = ktime_to_timespec( + ts = ktime_to_timespec64( ...) | - ts = E3 + ts = timespec_to_timespec64(E3) | - ktime_get_real_ts(&ts) + ktime_get_real_ts64(&ts) | fn(..., - ts + timespec64_to_timespec(ts) ,...) ) ...+> ( <... when != ts - return ts; + return timespec64_to_timespec(ts); ...> ) | - timespec_equal(&node1->i_xtime1, &node2->i_xtime2) + timespec64_equal(&node1->i_xtime2, &node2->i_xtime2) | - timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2) + timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2) | - timespec_compare(&node1->i_xtime1, &node2->i_xtime2) + timespec64_compare(&node1->i_xtime1, &node2->i_xtime2) | node1->i_xtime1 = - timespec_trunc(attr1->ia_xtime1, + timespec64_trunc(attr1->ia_xtime1, ...) | - attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2, + attr1->ia_xtime1 = timespec64_trunc(attr2->ia_xtime2, ...) | - ktime_get_real_ts(&attr1->ia_xtime1) + ktime_get_real_ts64(&attr1->ia_xtime1) | - ktime_get_real_ts(&attr.ia_xtime1) + ktime_get_real_ts64(&attr.ia_xtime1) ) @ depends on patch @ struct inode *node; struct iattr *attr; identifier fn; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; expression e; @@ ( - fn(node->i_xtime); + fn(timespec64_to_timespec(node->i_xtime)); | fn(..., - node->i_xtime); + timespec64_to_timespec(node->i_xtime)); | - e = fn(attr->ia_xtime); + e = fn(timespec64_to_timespec(attr->ia_xtime)); ) @ depends on patch forall @ struct inode *node; struct iattr *attr; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); fn (..., - &attr->ia_xtime, + &ts, ...); ) ...+> } @ depends on patch forall @ struct inode *node; struct iattr *attr; struct kstat *stat; identifier ia_xtime =~ "^ia_[acm]time$"; identifier i_xtime =~ "^i_[acm]time$"; identifier xtime =~ "^[acm]time$"; identifier fn, ret; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime); + &ts); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime); + &ts); | + ts = timespec64_to_timespec(stat->xtime); ret = fn (..., - &stat->xtime); + &ts); ) ...+> } @ depends on patch @ struct inode *node; struct inode *node2; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier i_xtime3 =~ "^i_[acm]time$"; struct iattr *attrp; struct iattr *attrp2; struct iattr attr ; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; struct kstat *stat; struct kstat stat1; struct timespec64 ts; identifier xtime =~ "^[acmb]time$"; expression e; @@ ( ( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1 ; | node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | stat->xtime = node2->i_xtime1; | stat1.xtime = node2->i_xtime1; | ( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1 ; | ( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2; | - e = node->i_xtime1; + e = timespec64_to_timespec( node->i_xtime1 ); | - e = attrp->ia_xtime1; + e = timespec64_to_timespec( attrp->ia_xtime1 ); | node->i_xtime1 = current_time(...); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | - node->i_xtime1 = e; + node->i_xtime1 = timespec_to_timespec64(e); ) Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: <anton@tuxera.com> Cc: <balbi@kernel.org> Cc: <bfields@fieldses.org> Cc: <darrick.wong@oracle.com> Cc: <dhowells@redhat.com> Cc: <dsterba@suse.com> Cc: <dwmw2@infradead.org> Cc: <hch@lst.de> Cc: <hirofumi@mail.parknet.co.jp> Cc: <hubcap@omnibond.com> Cc: <jack@suse.com> Cc: <jaegeuk@kernel.org> Cc: <jaharkes@cs.cmu.edu> Cc: <jslaby@suse.com> Cc: <keescook@chromium.org> Cc: <mark@fasheh.com> Cc: <miklos@szeredi.hu> Cc: <nico@linaro.org> Cc: <reiserfs-devel@vger.kernel.org> Cc: <richard@nod.at> Cc: <sage@redhat.com> Cc: <sfrench@samba.org> Cc: <swhiteho@redhat.com> Cc: <tj@kernel.org> Cc: <trond.myklebust@primarydata.com> Cc: <tytso@mit.edu> Cc: <viro@zeniv.linux.org.uk>
2018-05-16proc: introduce proc_create_seq_privateChristoph Hellwig1-14/+2
Variant of proc_create_data that directly take a struct seq_operations argument + a private state size and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-03-26treewide: Align function definition open/close bracesJoe Perches1-1/+1
Some functions definitions have either the initial open brace and/or the closing brace outside of column 1. Move those braces to column 1. This allows various function analyzers like gnu complexity to work properly for these modified functions. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Nicolin Chen <nicoleotsuka@gmail.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-02-09Merge tag 'nfsd-4.16' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-4/+2
Pull nfsd update from Bruce Fields: "A fairly small update this time around. Some cleanup, RDMA fixes, overlayfs fixes, and a fix for an NFSv4 state bug. The bigger deal for nfsd this time around was Jeff Layton's already-merged i_version patches" * tag 'nfsd-4.16' of git://linux-nfs.org/~bfields/linux: svcrdma: Fix Read chunk round-up NFSD: hide unused svcxdr_dupstr() nfsd: store stat times in fill_pre_wcc() instead of inode times nfsd: encode stat->mtime for getattr instead of inode->i_mtime nfsd: return RESOURCE not GARBAGE_ARGS on too many ops nfsd4: don't set lock stateid's sc_type to CLOSED nfsd: Detect unhashed stids in nfsd4_verify_open_stid() sunrpc: remove dead code in svc_sock_setbufsize svcrdma: Post Receives in the Receive completion handler nfsd4: permit layoutget of executable-only files lockd: convert nlm_rqst.a_count from atomic_t to refcount_t lockd: convert nlm_lockowner.count from atomic_t to refcount_t lockd: convert nsm_handle.sm_count from atomic_t to refcount_t
2018-02-08nfsd: encode stat->mtime for getattr instead of inode->i_mtimeAmir Goldstein1-4/+2
The values of stat->mtime and inode->i_mtime may differ for overlayfs and stat->mtime is the correct value to use when encoding getattr. This is also consistent with the fact that other attr times are also encoded from stat values. Both callers of lease_get_mtime() already have the value of stat->mtime, so the only needed change is that lease_get_mtime() will not overwrite this value with inode->i_mtime in case the inode does not have an exclusive lease. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-28Rename superblock flags (MS_xyz -> SB_xyz)Linus Torvalds1-1/+1
This is a pure automated search-and-replace of the internal kernel superblock flags. The s_flags are now called SB_*, with the names and the values for the moment mirroring the MS_* flags that they're equivalent to. Note how the MS_xyz flags are the ones passed to the mount system call, while the SB_xyz flags are what we then use in sb->s_flags. The script to do this was: # places to look in; re security/*: it generally should *not* be # touched (that stuff parses mount(2) arguments directly), but # there are two places where we really deal with superblock flags. FILES="drivers/mtd drivers/staging/lustre fs ipc mm \ include/linux/fs.h include/uapi/linux/bfs_fs.h \ security/apparmor/apparmorfs.c security/apparmor/include/lib.h" # the list of MS_... constants SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \ DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \ POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \ I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \ ACTIVE NOUSER" SED_PROG= for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done # we want files that contain at least one of MS_..., # with fs/namespace.c and fs/pnode.c excluded. L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c') for f in $L; do sed -i $f $SED_PROG; done Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-21locks: restore a warn for leaked locks on closeBenjamin Coddington1-0/+22
When locks.c moved to using file_lock_context, the check for any locks that were not released was moved from the __fput() to destroy_inode() path in commit 8634b51f6ca2 ("locks: convert lease handling to file_lock_context"). This warning has been quite useful for catching bugs, particularly in NFS where lock handling still sees some churn. Let's bring back the warning for leaked locks on __fput, as this warning is much more likely to be seen and reported by users. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-16fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locksBenjamin Coddington1-25/+37
Since commit c69899a17ca4 "NFSv4: Update of VFS byte range lock must be atomic with the stateid update", NFSv4 has been inserting locks in rpciod worker context. The result is that the file_lock's fl_nspid is the kworker's pid instead of the original userspace pid. The fl_nspid is only used to represent the namespaced virtual pid number when displaying locks or returning from F_GETLK. There's no reason to set it for every inserted lock, since we can usually just look it up from fl_pid. So, instead of looking up and holding struct pid for every lock, let's just look up the virtual pid number from fl_pid when it is needed. That means we can remove fl_nspid entirely. The translaton and presentation of fl_pid should handle the following four cases: 1 - F_GETLK on a remote file with a remote lock: In this case, the filesystem should determine the l_pid to return here. Filesystems should indicate that the fl_pid represents a non-local pid value that should not be translated by returning an fl_pid <= 0. 2 - F_GETLK on a local file with a remote lock: This should be the l_pid of the lock manager process, and translated. 3 - F_GETLK on a remote file with a local lock, and 4 - F_GETLK on a local file with a local lock: These should be the translated l_pid of the local locking process. Fuse was already doing the correct thing by translating the pid into the caller's namespace. With this change we must update fuse to translate to init's pid namespace, so that the locks API can then translate from init's pid namespace into the pid namespace of the caller. With this change, the locks API will expect that if a filesystem returns a remote pid as opposed to a local pid for F_GETLK, that remote pid will be <= 0. This signifies that the pid is remote, and the locks API will forego translating that pid into the pid namespace of the local calling process. Finally, we convert remote filesystems to present remote pids using negative numbers. Have lustre, 9p, ceph, cifs, and dlm negate the remote pid returned for F_GETLK lock requests. Since local pids will never be larger than PID_MAX_LIMIT (which is currently defined as <= 4 million), but pid_t is an unsigned int, we should have plenty of room to represent remote pids with negative numbers if we assume that remote pid numbers are similarly limited. If this is not the case, then we run the risk of having a remote pid returned for which there is also a corresponding local pid. This is a problem we have now, but this patch should reduce the chances of that occurring, while also returning those remote pid numbers, for whatever that may be worth. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-16fs/locks: Use allocation rather than the stack in fcntl_getlk()Benjamin Coddington1-20/+26
Struct file_lock is fairly large, so let's save some space on the stack by using an allocation for struct file_lock in fcntl_getlk(), just as we do for fcntl_setlk(). Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-05-27fs/locks: pass kernel struct flock to fcntl_getlk/setlkChristoph Hellwig1-57/+22
This will make it easier to implement a sane compat fcntl syscall. [ jlayton: fix undeclared identifiers in 32-bit fcntl64 syscall handler ] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-05-27fs: locks: Fix some troubles at kernel-doc commentsMauro Carvalho Chehab1-10/+8
There are a few syntax violations that cause outputs of a few comments to not be properly parsed in ReST format. No functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-04-21locks: Set FL_CLOSE when removing flock locks on close()Benjamin Coddington1-1/+1
Set FL_CLOSE in fl_flags as in locks_remove_posix() when clearing locks. NFS will check for this flag to ensure an unlock is sent in a following patch. Fuse handles flock and posix locks differently for FL_CLOSE, and so requires a fixup to retain the existing behavior for flock. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-18locking, fs/locks: Add missing file_sem locksPeter Zijlstra1-0/+6
I overlooked a few code-paths that can lead to locks_delete_global_locks(). Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Jeff Layton <jlayton@poochiereds.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Bruce Fields <bfields@fieldses.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-fsdevel@vger.kernel.org Cc: syzkaller <syzkaller@googlegroups.com> Link: http://lkml.kernel.org/r/20161008081228.GF3142@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-11Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: ">rename2() work from Miklos + current_time() from Deepa" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Replace current_fs_time() with current_time() fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps fs: Replace CURRENT_TIME with current_time() for inode timestamps fs: proc: Delete inode time initializations in proc_alloc_inode() vfs: Add current_time() api vfs: add note about i_op->rename changes to porting fs: rename "rename2" i_op to "rename" vfs: remove unused i_op->rename fs: make remaining filesystems use .rename2 libfs: support RENAME_NOREPLACE in simple_rename() fs: support RENAME_NOREPLACE for local filesystems ncpfs: fix unused variable warning
2016-10-10Merge branch 'work.misc' of ↵Linus Torvalds1-23/+30
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted misc bits and pieces. There are several single-topic branches left after this (rename2 series from Miklos, current_time series from Deepa Dinamani, xattr series from Andreas, uaccess stuff from from me) and I'd prefer to send those separately" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits) proc: switch auxv to use of __mem_open() hpfs: support FIEMAP cifs: get rid of unused arguments of CIFSSMBWrite() posix_acl: uapi header split posix_acl: xattr representation cleanups fs/aio.c: eliminate redundant loads in put_aio_ring_file fs/internal.h: add const to ns_dentry_operations declaration compat: remove compat_printk() fs/buffer.c: make __getblk_slow() static proc: unsigned file descriptors fs/file: more unsigned file descriptors fs: compat: remove redundant check of nr_segs cachefiles: Fix attempt to read i_blocks after deleting file [ver #2] cifs: don't use memcpy() to copy struct iov_iter get rid of separate multipage fault-in primitives fs: Avoid premature clearing of capabilities fs: Give dentry to inode_change_ok() instead of inode fuse: Propagate dentry down to inode_change_ok() ceph: Propagate dentry down to inode_change_ok() xfs: Propagate dentry down to inode_change_ok() ...
2016-10-04Merge tag 'locks-v4.9-1' of git://git.samba.org/jlayton/linuxLinus Torvalds1-3/+18
Pull file locking updates from Jeff Layton: "Only a single patch from Nikolay this cycle, with a small change to better handle /proc/locks in a containerized host" * tag 'locks-v4.9-1' of git://git.samba.org/jlayton/linux: locks: Filter /proc/locks output on proc pid ns
2016-09-28fs: Replace current_fs_time() with current_time()Deepa Dinamani1-1/+1
current_fs_time() uses struct super_block* as an argument. As per Linus's suggestion, this is changed to take struct inode* as a parameter instead. This is because the function is primarily meant for vfs inode timestamps. Also the function was renamed as per Arnd's suggestion. Change all calls to current_fs_time() to use the new current_time() function instead. current_fs_time() will be deleted. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-22fs/locks: Use percpu_down_read_preempt_disable()Peter Zijlstra1-12/+12
Avoid spurious preemption. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: paulmck@linux.vnet.ibm.com Cc: riel@redhat.com Cc: tj@kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22fs/locks: Replace lg_local with a per-cpu spinlockPeter Zijlstra1-18/+29
As Oleg suggested, replace file_lock_list with a structure containing the hlist head and a spinlock. This completely removes the lglock from fs/locks. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: paulmck@linux.vnet.ibm.com Cc: riel@redhat.com Cc: tj@kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22fs/locks: Replace lg_global with a percpu-rwsemPeter Zijlstra1-0/+21
Replace the global part of the lglock with a percpu-rwsem. Since fcl_lock is a spinlock and itself nests under i_lock, which too is a spinlock we cannot acquire sleeping locks at locks_{insert,remove}_global_locks(). We can however wrap all fcl_lock acquisitions with percpu_down_read such that all invocations of locks_{insert,remove}_global_locks() have that read lock held. This allows us to replace the lg_global part of the lglock with the write side of the rwsem. In the absense of writers, percpu_{down,up}_read() are free of atomic instructions. This further avoids the very long preempt-disable regions caused by lglock on larger machines. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: paulmck@linux.vnet.ibm.com Cc: riel@redhat.com Cc: tj@kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-16vfs: do get_write_access() on upper layer of overlayfsMiklos Szeredi1-1/+2
The problem with writecount is: we want consistent handling of it for underlying filesystems as well as overlayfs. Making sure i_writecount is correct on all layers is difficult. Instead this patch makes sure that when write access is acquired, it's always done on the underlying writable layer (called the upper layer). We must also make sure to look at the writecount on this layer when checking for conflicting leases. Open for write already updates the upper layer's writecount. Leaving only truncate. For truncate copy up must happen before get_write_access() so that the writecount is updated on the upper layer. Problem with this is if something fails after that, then copy-up was done needlessly. E.g. if break_lease() was interrupted. Probably not a big deal in practice. Another interesting case is if there's a denywrite on a lower file that is then opened for write or truncated. With this patch these will succeed, which is somewhat counterintuitive. But I think it's still acceptable, considering that the copy-up does actually create a different file, so the old, denywrite mapping won't be touched. On non-overlayfs d_real() is an identity function and d_real_inode() is equivalent to d_inode() so this patch doesn't change behavior in that case. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: Jeff Layton <jlayton@poochiereds.net> Cc: "J. Bruce Fields" <bfields@fieldses.org>
2016-09-16locks: fix file locking on overlayfsMiklos Szeredi1-22/+28
This patch allows flock, posix locks, ofd locks and leases to work correctly on overlayfs. Instead of using the underlying inode for storing lock context use the overlay inode. This allows locks to be persistent across copy-up. This is done by introducing locks_inode() helper and using it instead of file_inode() to get the inode in locking code. For non-overlayfs the two are equivalent, except for an extra pointer dereference in locks_inode(). Since lock operations are in "struct file_operations" we must also make sure not to call underlying filesystem's lock operations. Introcude a super block flag MS_NOREMOTELOCK to this effect. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: Jeff Layton <jlayton@poochiereds.net> Cc: "J. Bruce Fields" <bfields@fieldses.org>
2016-08-18locks: Filter /proc/locks output on proc pid nsNikolay Borisov1-3/+18
On busy container servers reading /proc/locks shows all the locks created by all clients. This can cause large latency spikes. In my case I observed lsof taking up to 5-10 seconds while processing around 50k locks. Fix this by limiting the locks shown only to those created in the same pidns as the one the proc fs was mounted in. When reading /proc/locks from the init_pid_ns proc instance then perform no filtering [ jlayton: reformat comments for 80 columns ] Signed-off-by: Nikolay Borisov <kernel@kyup.com> Suggested-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2016-07-01locks: use file_inode()Miklos Szeredi1-1/+1
(Another one for the f_path debacle.) ltp fcntl33 testcase caused an Oops in selinux_file_send_sigiotask. The reason is that generic_add_lease() used filp->f_path.dentry->inode while all the others use file_inode(). This makes a difference for files opened on overlayfs since the former will point to the overlay inode the latter to the underlying inode. So generic_add_lease() added the lease to the overlay inode and generic_delete_lease() removed it from the underlying inode. When the file was released the lease remained on the overlay inode's lock list, resulting in use after free. Reported-by: Eryu Guan <eguan@redhat.com> Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Cc: <stable@vger.kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-01-23wrappers for ->i_mutex accessAl Viro1-3/+3
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>