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2013-09-11fs/bio-integrity: fix a potential mem leakGu Zheng
Free the bio_integrity_pool in the fail path of biovec_create_pool in function bioset_integrity_create(). Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11writeback: fix race that cause writeback hungJunxiao Bi
There is a race between mark inode dirty and writeback thread, see the following scenario. In this case, writeback thread will not run though there is dirty_io. __mark_inode_dirty() bdi_writeback_workfn() ... ... spin_lock(&inode->i_lock); ... if (bdi_cap_writeback_dirty(bdi)) { <<< assume wb has dirty_io, so wakeup_bdi is false. <<< the following inode_dirty also have wakeup_bdi false. if (!wb_has_dirty_io(&bdi->wb)) wakeup_bdi = true; } spin_unlock(&inode->i_lock); <<< assume last dirty_io is removed here. pages_written = wb_do_writeback(wb); ... <<< work_list empty and wb has no dirty_io, <<< delayed_work will not be queued. if (!list_empty(&bdi->work_list) || (wb_has_dirty_io(wb) && dirty_writeback_interval)) queue_delayed_work(bdi_wq, &wb->dwork, msecs_to_jiffies(dirty_writeback_interval * 10)); spin_lock(&bdi->wb.list_lock); inode->dirtied_when = jiffies; <<< new dirty_io is added. list_move(&inode->i_wb_list, &bdi->wb.b_dirty); spin_unlock(&bdi->wb.list_lock); <<< though there is dirty_io, but wakeup_bdi is false, <<< so writeback thread will not be waked up and <<< the new dirty_io will not be flushed. if (wakeup_bdi) bdi_wakeup_thread_delayed(bdi); Writeback will run until there is a new flush work queued. This may cause a lot of dirty pages stay in memory for a long time. Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11mm/page-writeback.c: add strictlimit featureMaxim Patlasov
The feature prevents mistrusted filesystems (ie: FUSE mounts created by unprivileged users) to grow a large number of dirty pages before throttling. For such filesystems balance_dirty_pages always check bdi counters against bdi limits. I.e. even if global "nr_dirty" is under "freerun", it's not allowed to skip bdi checks. The only use case for now is fuse: it sets bdi max_ratio to 1% by default and system administrators are supposed to expect that this limit won't be exceeded. The feature is on if a BDI is marked by BDI_CAP_STRICTLIMIT flag. A filesystem may set the flag when it initializes its BDI. The problematic scenario comes from the fact that nobody pays attention to the NR_WRITEBACK_TEMP counter (i.e. number of pages under fuse writeback). The implementation of fuse writeback releases original page (by calling end_page_writeback) almost immediately. A fuse request queued for real processing bears a copy of original page. Hence, if userspace fuse daemon doesn't finalize write requests in timely manner, an aggressive mmap writer can pollute virtually all memory by those temporary fuse page copies. They are carefully accounted in NR_WRITEBACK_TEMP, but nobody cares. To make further explanations shorter, let me use "NR_WRITEBACK_TEMP problem" as a shortcut for "a possibility of uncontrolled grow of amount of RAM consumed by temporary pages allocated by kernel fuse to process writeback". The problem was very easy to reproduce. There is a trivial example filesystem implementation in fuse userspace distribution: fusexmp_fh.c. I added "sleep(1);" to the write methods, then recompiled and mounted it. Then created a huge file on the mount point and run a simple program which mmap-ed the file to a memory region, then wrote a data to the region. An hour later I observed almost all RAM consumed by fuse writeback. Since then some unrelated changes in kernel fuse made it more difficult to reproduce, but it is still possible now. Putting this theoretical happens-in-the-lab thing aside, there is another thing that really hurts real world (FUSE) users. This is write-through page cache policy FUSE currently uses. I.e. handling write(2), kernel fuse populates page cache and flushes user data to the server synchronously. This is excessively suboptimal. Pavel Emelyanov's patches ("writeback cache policy") solve the problem, but they also make resolving NR_WRITEBACK_TEMP problem absolutely necessary. Otherwise, simply copying a huge file to a fuse mount would result in memory starvation. Miklos, the maintainer of FUSE, believes strictlimit feature the way to go. And eventually putting FUSE topics aside, there is one more use-case for strictlimit feature. Using a slow USB stick (mass storage) in a machine with huge amount of RAM installed is a well-known pain. Let's make simple computations. Assuming 64GB of RAM installed, existing implementation of balance_dirty_pages will start throttling only after 9.6GB of RAM becomes dirty (freerun == 15% of total RAM). So, the command "cp 9GB_file /media/my-usb-storage/" may return in a few seconds, but subsequent "umount /media/my-usb-storage/" will take more than two hours if effective throughput of the storage is, to say, 1MB/sec. After inclusion of strictlimit feature, it will be trivial to add a knob (e.g. /sys/devices/virtual/bdi/x:y/strictlimit) to enable it on demand. Manually or via udev rule. May be I'm wrong, but it seems to be quite a natural desire to limit the amount of dirty memory for some devices we are not fully trust (in the sense of sustainable throughput). [akpm@linux-foundation.org: fix warning in page-writeback.c] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Cc: Jan Kara <jack@suse.cz> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11mm/writeback: make writeback_inodes_wb staticWanpeng Li
It's not used globally and could be static. Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11mm: track vma changes with VM_SOFTDIRTY bitCyrill Gorcunov
Pavel reported that in case if vma area get unmapped and then mapped (or expanded) in-place, the soft dirty tracker won't be able to recognize this situation since it works on pte level and ptes are get zapped on unmap, loosing soft dirty bit of course. So to resolve this situation we need to track actions on vma level, there VM_SOFTDIRTY flag comes in. When new vma area created (or old expanded) we set this bit, and keep it here until application calls for clearing soft dirty bit. Thus when user space application track memory changes now it can detect if vma area is renewed. Reported-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Matt Mackall <mpm@selenic.com> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11writeback: fix occasional slow sync(1)Jan Kara
In case when system contains no dirty pages, wakeup_flusher_threads() will submit WB_SYNC_NONE writeback for 0 pages so wb_writeback() exits immediately without doing anything, even though there are dirty inodes in the system. Thus sync(1) will write all the dirty inodes from a WB_SYNC_ALL writeback pass which is slow. Fix the problem by using get_nr_dirty_pages() in wakeup_flusher_threads() instead of calculating number of dirty pages manually. That function also takes number of dirty inodes into account. Signed-off-by: Jan Kara <jack@suse.cz> Reported-by: Paul Taysom <taysom@chromium.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: fix the end cluster offset of FIEMAPJie Liu
Call fiemap ioctl(2) with given start offset as well as an desired mapping range should show extents if possible. However, we somehow figure out the end offset of mapping via 'mapping_end -= cpos' before iterating the extent records which would cause problems if the given fiemap length is too small to a cluster size, e.g, Cluster size 4096: debugfs.ocfs2 1.6.3 Block Size Bits: 12 Cluster Size Bits: 12 The extended fiemap test utility From David: https://gist.github.com/anonymous/6172331 # dd if=/dev/urandom of=/ocfs2/test_file bs=1M count=1000 # ./fiemap /ocfs2/test_file 4096 10 start: 4096, length: 10 File /ocfs2/test_file has 0 extents: # Logical Physical Length Flags ^^^^^ <-- No extent is shown In this case, at ocfs2_fiemap(): cpos == mapping_end == 1. Hence the loop of searching extent records was not executed at all. This patch remove the in question 'mapping_end -= cpos', and loops until the cpos is larger than the mapping_end as usual. # ./fiemap /ocfs2/test_file 4096 10 start: 4096, length: 10 File /ocfs2/test_file has 1 extents: # Logical Physical Length Flags 0: 0000000000000000 0000000056a01000 0000000006a00000 0000 Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reported-by: David Weber <wb@munzinger.de> Tested-by: David Weber <wb@munzinger.de> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: Mark Fashen <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: remove unused variable ip in dlmfs_get_root_inode()Joseph Qi
Variable ip in dlmfs_get_root_inode() is defined but not used. So clean it up. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: fix a tiny race case when firing callbacksJoyce
In o2hb_shutdown_slot() and o2hb_check_slot(), since event is defined as local, it is only valid during the call stack. So the following tiny race case may happen in a multi-volumes mounted environment: o2hb-vol1 o2hb-vol2 1) o2hb_shutdown_slot allocate local event1 2) queue_node_event add event1 to global o2hb_node_events 3) o2hb_shutdown_slot allocate local event2 4) queue_node_event add event2 to global o2hb_node_events 5) o2hb_run_event_list delete event1 from o2hb_node_events 6) o2hb_run_event_list event1 empty, return 7) o2hb_shutdown_slot event1 lifecycle ends 8) o2hb_fire_callbacks event1 is already *invalid* This patch lets it wait on o2hb_callback_sem when another thread is firing callbacks. And for performance consideration, we only call o2hb_run_event_list when there is an event queued. Signed-off-by: Joyce <xuejiufei@huawei.com> Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: avoid possible NULL pointer dereference in o2net_accept_one()Joseph Qi
Since o2nm_get_node_by_num() may return NULL, we add this check in o2net_accept_one() to avoid possible NULL pointer dereference. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: adjust code style for o2net_handler_tree_lookup()Joseph Qi
Code in o2net_handler_tree_lookup() may be corrupted by mistake. So adjust it to promote readability. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: free path in ocfs2_remove_inode_range()Younger Liu
In ocfs2_remove_inode_range(), there is a memory leak. The variable path has allocated memory with ocfs2_new_path_from_et(), but it is not free. Signed-off-by: Younger Liu <younger.liu@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: fix possible double free in ocfs2_reflink_xattr_recJoseph Qi
In ocfs2_reflink_xattr_rec(), meta_ac and data_ac are allocated by calling ocfs2_lock_reflink_xattr_rec_allocators(). Once an error occurs when allocating *data_ac, it frees *meta_ac which is allocated before. Here it mistakenly sets meta_ac to NULL but *meta_ac. Then ocfs2_reflink_xattr_rec() will try to free meta_ac again which is already invalid. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2/dlm: force clean refmap when doing local cleanupXue jiufei
dlm_do_local_recovery_cleanup() should force clean refmap if the owner of lockres is UNKNOWN. Otherwise node may hang when umounting filesystems. Here's the situation: Node1 Node2 dlmlock() -> dlm_get_lock_resource() send DLM_MASTER_REQUEST_MSG to other nodes. trying to master this lockres, return MAYBE. selected as the master of lockresA, set mle->master to Node1, and do assert_master, send DLM_ASSERT_MASTER_MSG to Node2. Node 2 has interest on lockresA and return DLM_ASSERT_RESPONSE_MASTERY_REF then something happened and Node2 crashed. Receiving DLM_ASSERT_RESPONSE_MASTERY_REF, set Node2 into refmap, and keep sending DLM_ASSERT_MASTER_MSG to other nodes o2hb found node2 down, calling dlm_hb_node_down() --> dlm_do_local_recovery_cleanup() the master of lockresA is still UNKNOWN, no need to call dlm_free_dead_locks(). Set the master of lockresA to Node1, but Node2 stills remains in refmap. When Node1 umount, it found that the refmap of lockresA is not empty and attempted to migrate it to Node2, But Node2 is already down, so umount hang, trying to migrate lockresA again and again. Signed-off-by: joyce <xuejiufei@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jie Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: free meta_ac and data_ac when ocfs2_start_trans fails in ↵Younger Liu
ocfs2_xattr_set() In ocfs2_xattr_set(), if ocfs2_start_trans failed, meta_ac and data_ac should be free. Otherwise, It would lead to a memory leak. Signed-off-by: Younger Liu <younger.liu@huawei.com> Cc: Joseph Qi <joseph.qi@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: add the missing return value check of ocfs2_xattr_get_clustersJoseph Qi
In ocfs2_xattr_value_attach_refcount(), if error occurs when calling ocfs2_xattr_get_clusters(), it will go with unexpected behavior since local variables p_cluster, num_clusters and ext_flags are declared without initialization. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Jie Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: fix a memory leak in __ocfs2_move_extents()Jie Liu
The ocfs2 path is not properly freed which leads to a memory leak at __ocfs2_move_extents(). This patch stops the leaks of the ocfs2_path structure. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Younger Liu <younger.liu@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: add missing return value check of ocfs2_get_clusters()Joseph Qi
In ocfs2_attach_refcount_tree() and ocfs2_duplicate_extent_list(), if error occurs when calling ocfs2_get_clusters(), it will go with unexpected behavior as local variables p_cluster, num_clusters and ext_flags are declared without initialization. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: clean up dead code in ocfs2_acl_from_xattr()Joseph Qi
In ocfs2_acl_from_xattr(), if size is less than sizeof(struct posix_acl_entry), it returns ERR_PTR(-EINVAL) directly. Then assign (size / sizeof(struct posix_acl_entry)) to count which will be at least 1, that means the following branch (count < 0) and (count == 0) will never be true. Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: use list_for_each_entry() instead of list_for_each()Dong Fang
[dan.carpenter@oracle.com: fix up some NULL dereference bugs] Signed-off-by: Dong Fang <yp.fangdong@gmail.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jeff Liu <jeff.liu@oracle.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11fs/ocfs2/cluster/tcp.c: fix possible null pointer dereferencesSunil Mushran
Fix some possible null pointer dereferences that were detected by the static code analyser, smatch. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Reported-by: Dan Carpenter <error27@gmail.com> Reported-by: Guozhonghua <guozhonghua@h3c.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: ac_bits_wanted should be local_alloc_bits when returns -ENOSPCYounger Liu
There is an issue in reserving and claiming space for localalloc, When localalloc space is not enough, it would claim space from global_bitmap. And if there is not enough free space in global_bitmap, the size of claiming space would set to half of orignal size and retry. The issue is as follows: osb->local_alloc_bits is set to half of orignal size in ocfs2_recalc_la_window(), but ac->ac_bits_wanted is set to osb->local_alloc_default_bits which is not changed. localalloc always reserves and claims local_alloc_default_bits space and returns ENOSPC. So, ac->ac_bits_wanted should be osb->local_alloc_bits which would be changed. Signed-off-by: Younger Liu <younger.liu@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Jeff Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: dlm_request_all_locks() should deal with the status sent from target nodeXue jiufei
dlm_request_all_locks() should deal with the status sent from target node if DLM_LOCK_REQUEST_MSG is sent successfully, or recovery master will fall into endless loop, waiting for other nodes to send locks and DLM_RECO_DATA_DONE_MSG to me. NodeA NodeB selected as recovery master dlm_remaster_locks() ->dlm_request_all_locks() send DLM_LOCK_REQUEST_MSG to nodeA It happened that NodeA cannot alloc memory when it processes this message. dlm_request_all_locks_handler() do not queue dlm_request_all_locks_worker and returns -ENOMEM. It will never send locks and DLM_RECO_DATA_DONE_MSG to NodeB. NodeB do not deal with the status sent from nodeA, and will fall in endless loop waiting for the recovery state of NodeA to be changed. Signed-off-by: joyce <xuejiufei@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Jeff Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: use i_size_read() to access i_sizeJunxiao Bi
Though ocfs2 uses inode->i_mutex to protect i_size, there are both i_size_read/write() and direct accesses. Clean up all direct access to eliminate confusion. Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11ocfs2: lighten up allocate transactionYounger Liu
The issue scenario is as following: When fallocating a very large disk space for a small file, __ocfs2_extend_allocation attempts to get a very large transaction. For some journal sizes, there may be not enough room for this transaction, and the fallocate will fail. The patch below extends & restarts the transaction as necessary while allocating space, and should work with even the smallest journal. This patch refers ext4 resize. Test: # mkfs.ocfs2 -b 4K -C 32K -T datafiles /dev/sdc ...(jounral size is 32M) # mount.ocfs2 /dev/sdc /mnt/ocfs2/ # touch /mnt/ocfs2/1.log # fallocate -o 0 -l 400G /mnt/ocfs2/1.log fallocate: /mnt/ocfs2/1.log: fallocate failed: Cannot allocate memory # tail -f /var/log/messages [ 7372.278591] JBD: fallocate wants too many credits (2051 > 2048) [ 7372.278597] (fallocate,6438,0):__ocfs2_extend_allocation:709 ERROR: status = -12 [ 7372.278603] (fallocate,6438,0):ocfs2_allocate_unwritten_extents:1504 ERROR: status = -12 [ 7372.278607] (fallocate,6438,0):__ocfs2_change_file_space:1955 ERROR: status = -12 ^C With this patch, the test works well. Signed-off-by: Younger Liu <younger.liu@huawei.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-10Merge branch 'nfsd-next' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "This was a very quiet cycle! Just a few bugfixes and some cleanup" * 'nfsd-next' of git://linux-nfs.org/~bfields/linux: rpc: let xdr layer allocate gssproxy receieve pages rpc: fix huge kmalloc's in gss-proxy rpc: comment on linux_cred encoding, treat all as unsigned rpc: clean up decoding of gssproxy linux creds svcrpc: remove unused rq_resused nfsd4: nfsd4_create_clid_dir prints uninitialized data nfsd4: fix leak of inode reference on delegation failure Revert "nfsd: nfs4_file_get_access: need to be more careful with O_RDWR" sunrpc: prepare NFS for 2038 nfsd4: fix setlease error return nfsd: nfs4_file_get_access: need to be more careful with O_RDWR
2013-09-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 3 (of many) from Al Viro: "Waiman's conversion of d_path() and bits related to it, kern_path_mountpoint(), several cleanups and fixes (exportfs one is -stable fodder, IMO). There definitely will be more... ;-/" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: split read_seqretry_or_unlock(), convert d_walk() to resulting primitives dcache: Translating dentry into pathname without taking rename_lock autofs4 - fix device ioctl mount lookup introduce kern_path_mountpoint() rename user_path_umountat() to user_path_mountpoint_at() take unlazy_walk() into umount_lookup_last() Kill indirect include of file.h from eventfd.h, use fdget() in cgroup.c prune_super(): sb->s_op is never NULL exportfs: don't assume that ->iterate() won't feed us too long entries afs: get rid of redundant ->d_name.len checks
2013-09-10vfs: make sure we don't have a stale root path if unlazy_walk() failsLinus Torvalds
When I moved the RCU walk termination into unlazy_walk(), I didn't copy quite all of it: for the successful RCU termination we properly add the necessary reference counts to our temporary copy of the root path, but for the failure case we need to make sure that any temporary root path information is cleared out (since it does _not_ have the proper reference counts from the RCU lookup). We could clean up this mess by just always dropping the temporary root information, but Al points out that that would mean that a single lookup through symlinks could see multiple different root entries if it races with another thread doing chroot. Not that I think we should really care (we had that before too, back before we had a copy of the root path in the nameidata). Al says he has a cunning plan. In the meantime, this is the minimal fix for the problem, even if it's not all that pretty. Reported-by: Mace Moneta <moneta.mace@gmail.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-09split read_seqretry_or_unlock(), convert d_walk() to resulting primitivesAl Viro
Separate "check if we need to retry" from "unlock if we are done and had seq_writelock"; that allows to use these guys in d_walk(), where we need to recheck every time we ascend back to parent, but do *not* want to unlock until the very end. Lift rcu_read_lock/rcu_read_unlock out into callers. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-09Merge tag 'xfs-for-linus-v3.12-rc1' of git://oss.sgi.com/xfs/xfsLinus Torvalds
Pull xfs updates from Ben Myers: "For 3.12-rc1 there are a number of bugfixes in addition to work to ease usage of shared code between libxfs and the kernel, the rest of the work to enable project and group quotas to be used simultaneously, performance optimisations in the log and the CIL, directory entry file type support, fixes for log space reservations, some spelling/grammar cleanups, and the addition of user namespace support. - introduce readahead to log recovery - add directory entry file type support - fix a number of spelling errors in comments - introduce new Q_XGETQSTATV quotactl for project quotas - add USER_NS support - log space reservation rework - CIL optimisations - kernel/userspace libxfs rework" * tag 'xfs-for-linus-v3.12-rc1' of git://oss.sgi.com/xfs/xfs: (112 commits) xfs: XFS_MOUNT_QUOTA_ALL needed by userspace xfs: dtype changed xfs_dir2_sfe_put_ino to xfs_dir3_sfe_put_ino Fix wrong flag ASSERT in xfs_attr_shortform_getvalue xfs: finish removing IOP_* macros. xfs: inode log reservations are too small xfs: check correct status variable for xfs_inobt_get_rec() call xfs: inode buffers may not be valid during recovery readahead xfs: check LSN ordering for v5 superblocks during recovery xfs: btree block LSN escaping to disk uninitialised XFS: Assertion failed: first <= last && last < BBTOB(bp->b_length), file: fs/xfs/xfs_trans_buf.c, line: 568 xfs: fix bad dquot buffer size in log recovery readahead xfs: don't account buffer cancellation during log recovery readahead xfs: check for underflow in xfs_iformat_fork() xfs: xfs_dir3_sfe_put_ino can be static xfs: introduce object readahead to log recovery xfs: Simplify xfs_ail_min() with list_first_entry_or_null() xfs: Register hotcpu notifier after initialization xfs: add xfs sb v4 support for dirent filetype field xfs: Add write support for dirent filetype field xfs: Add read-only support for dirent filetype field ...
2013-09-09direct-io: Use return from cmpxchg to decide of assignment happenedOlof Johansson
Not using the return value can in the generic case be racy, so it's in general good practice to check the return value instead. This also resolved the warning caused on ARM and other architectures: fs/direct-io.c: In function 'sb_init_dio_done_wq': fs/direct-io.c:557:2: warning: value computed is not used [-Wunused-value] Signed-off-by: Olof Johansson <olof@lixom.net> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: H Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-09dcache: Translating dentry into pathname without taking rename_lockWaiman Long
When running the AIM7's short workload, Linus' lockref patch eliminated most of the spinlock contention. However, there were still some left: 8.46% reaim [kernel.kallsyms] [k] _raw_spin_lock |--42.21%-- d_path | proc_pid_readlink | SyS_readlinkat | SyS_readlink | system_call | __GI___readlink | |--40.97%-- sys_getcwd | system_call | __getcwd The big one here is the rename_lock (seqlock) contention in d_path() and the getcwd system call. This patch will eliminate the need to take the rename_lock while translating dentries into the full pathnames. The need to take the rename_lock is to make sure that no rename operation can be ongoing while the translation is in progress. However, only one thread can take the rename_lock thus blocking all the other threads that need it even though the translation process won't make any change to the dentries. This patch will replace the writer's write_seqlock/write_sequnlock sequence of the rename_lock of the callers of the prepend_path() and __dentry_path() functions with the reader's read_seqbegin/read_seqretry sequence within these 2 functions. As a result, the code will have to retry if one or more rename operations had been performed. In addition, RCU read lock will be taken during the translation process to make sure that no dentries will go away. To prevent live-lock from happening, the code will switch back to take the rename_lock if read_seqretry() fails for three times. To further reduce spinlock contention, this patch does not take the dentry's d_lock when copying the filename from the dentries. Instead, it treats the name pointer and length as unreliable and just copy the string byte-by-byte over until it hits a null byte or the end of string as specified by the length. This should avoid stepping into invalid memory address. The error cases are left to be handled by the sequence number check. The following code re-factoring are also made: 1. Move prepend('/') into prepend_name() to remove one conditional check. 2. Move the global root check in prepend_path() back to the top of the while loop. With this patch, the _raw_spin_lock will now account for only 1.2% of the total CPU cycles for the short workload. This patch also has the effect of reducing the effect of running perf on its profile since the perf command itself can be a heavy user of the d_path() function depending on the complexity of the workload. When taking the perf profile of the high-systime workload, the amount of spinlock contention contributed by running perf without this patch was about 16%. With this patch, the spinlock contention caused by the running of perf will go away and we will have a more accurate perf profile. Signed-off-by: Waiman Long <Waiman.Long@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-09Merge tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates from Trond Myklebust: "Highlights include: - Fix NFSv4 recovery so that it doesn't recover lost locks in cases such as lease loss due to a network partition, where doing so may result in data corruption. Add a kernel parameter to control choice of legacy behaviour or not. - Performance improvements when 2 processes are writing to the same file. - Flush data to disk when an RPCSEC_GSS session timeout is imminent. - Implement NFSv4.1 SP4_MACH_CRED state protection to prevent other NFS clients from being able to manipulate our lease and file locking state. - Allow sharing of RPCSEC_GSS caches between different rpc clients. - Fix the broken NFSv4 security auto-negotiation between client and server. - Fix rmdir() to wait for outstanding sillyrename unlinks to complete - Add a tracepoint framework for debugging NFSv4 state recovery issues. - Add tracing to the generic NFS layer. - Add tracing for the SUNRPC socket connection state. - Clean up the rpc_pipefs mount/umount event management. - Merge more patches from Chuck in preparation for NFSv4 migration support" * tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (107 commits) NFSv4: use mach cred for SECINFO_NO_NAME w/ integrity NFS: nfs_compare_super shouldn't check the auth flavour unless 'sec=' was set NFSv4: Allow security autonegotiation for submounts NFSv4: Disallow security negotiation for lookups when 'sec=' is specified NFSv4: Fix security auto-negotiation NFS: Clean up nfs_parse_security_flavors() NFS: Clean up the auth flavour array mess NFSv4.1 Use MDS auth flavor for data server connection NFS: Don't check lock owner compatability unless file is locked (part 2) NFS: Don't check lock owner compatibility in writes unless file is locked nfs4: Map NFS4ERR_WRONG_CRED to EPERM nfs4.1: Add SP4_MACH_CRED write and commit support nfs4.1: Add SP4_MACH_CRED stateid support nfs4.1: Add SP4_MACH_CRED secinfo support nfs4.1: Add SP4_MACH_CRED cleanup support nfs4.1: Add state protection handler nfs4.1: Minimal SP4_MACH_CRED implementation SUNRPC: Replace pointer values with task->tk_pid and rpc_clnt->cl_clid SUNRPC: Add an identifier for struct rpc_clnt SUNRPC: Ensure rpc_task->tk_pid is available for tracepoints ...
2013-09-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse bugfixes from Miklos Szeredi: "Just a bunch of bugfixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: use list_for_each_entry() for list traversing fuse: readdir: check for slash in names fuse: hotfix truncate_pagecache() issue fuse: invalidate inode attributes on xattr modification fuse: postpone end_page_writeback() in fuse_writepage_locked()
2013-09-09Merge tag 'gfs2-merge-window' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw Pull GFS2 updates from Steven Whitehouse: "This is possibly the smallest ever set of GFS2 patches for a merge window. Also, most of them are bug fixes this time. Two of my three patches (moving gfs2_sync_meta and merging the two writepage implementations) are clean ups with the third (taking the glock ref in examine_bucket) being a fix for a difficult to hit race condition. The removal of an unused memory barrier is a clean up from Bob Peterson, and the "spectator" relates to a rarely used mount option. Ben Marzinski's patch fixes a corner case where the incorrect inode flags were being set, resulting in incorrect behaviour on fsync" * tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: GFS2: dirty inode correctly in gfs2_write_end GFS2: Don't flag consistency error if first mounter is a spectator GFS2: Remove unnecessary memory barrier GFS2: Merge ordered and writeback writepage GFS2: Take glock reference in examine_bucket() GFS2: Move gfs2_sync_meta to lops.c
2013-09-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull ceph updates from Sage Weil: "This includes both the first pile of Ceph patches (which I sent to torvalds@vger, sigh) and a few new patches that add support for fscache for Ceph. That includes a few fscache core fixes that David Howells asked go through the Ceph tree. (Thanks go to Milosz Tanski for putting this feature together) This first batch of patches (included here) had (has) several important RBD bug fixes, hole punch support, several different cleanups in the page cache interactions, improvements in the truncate code (new truncate mutex to avoid shenanigans with i_mutex), and a series of fixes in the synchronous striping read/write code. On top of that is a random collection of small fixes all across the tree (error code checks and error path cleanup, obsolete wq flags, etc)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (43 commits) ceph: use d_invalidate() to invalidate aliases ceph: remove ceph_lookup_inode() ceph: trivial buildbot warnings fix ceph: Do not do invalidate if the filesystem is mounted nofsc ceph: page still marked private_2 ceph: ceph_readpage_to_fscache didn't check if marked ceph: clean PgPrivate2 on returning from readpages ceph: use fscache as a local presisent cache fscache: Netfs function for cleanup post readpages FS-Cache: Fix heading in documentation CacheFiles: Implement interface to check cache consistency FS-Cache: Add interface to check consistency of a cached object rbd: fix null dereference in dout rbd: fix buffer size for writes to images with snapshots libceph: use pg_num_mask instead of pgp_num_mask for pg.seed calc rbd: fix I/O error propagation for reads ceph: use vfs __set_page_dirty_nobuffers interface instead of doing it inside filesystem ceph: allow sync_read/write return partial successed size of read/write. ceph: fix bugs about handling short-read for sync read mode. ceph: remove useless variable revoked_rdcache ...
2013-09-09Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds
Pull UML updates from Richard Weinberger: "This pile contains mostly fixes and improvements for issues identified by Richard W M Jones while adding UML as backend to libguestfs" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: Add irq chip um/mask handlers um: prctl: Do not include linux/ptrace.h um: Run UML in it's own session. um: Cleanup SIGTERM handling um: ubd: Introduce submit_request() um: ubd: Add REQ_FLUSH suppport um: Implement probe_kernel_read() um: hostfs: Fix writeback
2013-09-08autofs4 - fix device ioctl mount lookupIan Kent
When reconnecting to automounts at startup an autofs ioctl is used to find the device and inode of existing mounts so they can be used to open a file descriptor of possibly covered mounts. At this time the the caller might not yet "own" the mount so it can trigger calling ->d_automount(). This causes automount to hang when trying to reconnect to direct or offset mount types. Consequently kern_path() can't be used but kern_path_mountpoint() can be. Signed-off-by: Ian Kent <raven@themaw.net> Cc: Jeff Layton <jlayton@redhat.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-08vfs: fix dentry RCU to refcounting possibly sleeping dput()Linus Torvalds
This is the fix that the last two commits indirectly led up to - making sure that we don't call dput() in a bad context on the dentries we've looked up in RCU mode after the sequence count validation fails. This basically expands d_rcu_to_refcount() into the callers, and then fixes the callers to delay the dput() in the failure case until _after_ we've dropped all locks and are no longer in an RCU-locked region. The case of 'complete_walk()' was trivial, since its failure case did the unlock_rcu_walk() directly after the call to d_rcu_to_refcount(), and as such that is just a pure expansion of the function with a trivial movement of the resulting dput() to after 'unlock_rcu_walk()'. In contrast, the unlazy_walk() case was much more complicated, because not only does convert two different dentries from RCU to be reference counted, but it used to not call unlock_rcu_walk() at all, and instead just returned an error and let the caller clean everything up in "terminate_walk()". Happily, one of the dentries in question (called "parent" inside unlazy_walk()) is the dentry of "nd->path", which terminate_walk() wants a refcount to anyway for the non-RCU case. So what the new and improved unlazy_walk() does is to first turn that dentry into a refcounted one, and once that is set up, the error cases can continue to use the terminate_walk() helper for cleanup, but for the non-RCU case. Which makes it possible to drop out of RCU mode if we actually hit the sequence number failure case. Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-08introduce kern_path_mountpoint()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-08rename user_path_umountat() to user_path_mountpoint_at()Al Viro
... and move the extern from linux/namei.h to fs/internal.h, along with that of vfs_path_lookup(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-08take unlazy_walk() into umount_lookup_last()Al Viro
... and massage it a bit to reduce nesting Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-08vfs: use lockred "dead" flag to mark unrecoverably dead dentriesLinus Torvalds
This simplifies the RCU to refcounting code in particular. I was originally intending to leave this for later, but walking through all the dput() logic (see previous commit), I realized that the dput() "might_sleep()" check was misleadingly weak. And I removed it as misleading, both for performance profiling and for debugging. However, the might_sleep() debugging case is actually true: the final dput() can indeed sleep, if the inode of the dentry that you are releasing ends up sleeping at iput time (see dentry_iput()). So the problem with the might_sleep() in dput() wasn't that it wasn't true, it was that it wasn't actually testing and triggering on the interesting case. In particular, just about *any* dput() can indeed sleep, if you happen to race with another thread deleting the file in question, and you then lose the race to the be the last dput() for that file. But because it's a very rare race, the debugging code would never trigger it in practice. Why is this problematic? The new d_rcu_to_refcount() (see commit 15570086b590: "vfs: reimplement d_rcu_to_refcount() using lockref_get_or_lock()") does a dput() for the failure case, and it does it under the RCU lock. So potentially sleeping really is a bug. But there's no way I'm going to fix this with the previous complicated "lockref_get_or_lock()" interface. And rather than revert to the old and crufty nested dentry locking code (which did get this right by delaying the reference count updates until they were verified to be safe), let's make forward progress. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-08vfs: reorganize dput() memory accessesLinus Torvalds
This is me being a bit OCD after all the dentry optimization work this merge window: profiles end up showing 'dput()' as a rather expensive operation, and there were two unrelated bad reasons for that. The first reason was reading d_lockref.count for debugging purposes, which touches the lockref cacheline (for reads) before really need to. More importantly, the debugging test in question is _wrong_, and has hidden bugs. It's true that we can only sleep when the count goes down to zero, but the test as-is hides the much more subtle bug that happens if we race with somebody else deleting the file. Anyway we _will_ touch that cacheline, but let's do it for a write and in the right routine (ie in "lockref_put_or_lock()") which annotates the costs better. So remove the misleading debug code. The other was an unnecessary access to the cacheline that contains the d_lru list, just to check whether we already were on the LRU list or not. This is exactly what we have d_flags for, so that we can avoid touching extra cache lines for the common case. So just add another bit for "is this dentry on the LRU". Finally, mark the tests properly likely/unlikely, so that the common fast-paths are dense in the instruction stream. This makes the profiles look much saner. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-07prune_super(): sb->s_op is never NULLAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-07exportfs: don't assume that ->iterate() won't feed us too long entriesAl Viro
On some filesystems it's impossible even with fs corruption, but we'd better not rely on that, what with memcpy() into on-stack array we are doing there. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-07afs: get rid of redundant ->d_name.len checksAl Viro
No dentry can get to directory modification methods without having passed either ->lookup() or ->atomic_open(); if name is rejected by those two (or by ->d_hash()) with an error, it won't be seen by anything else. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-07NFSv4: use mach cred for SECINFO_NO_NAME w/ integrityWeston Andros Adamson
Commit 97431204ea005ec8070ac94bc3251e836daa7ca7 introduced a regression that causes SECINFO_NO_NAME to fail without sending an RPC if: 1) the nfs_client's rpc_client is using krb5i/p (now tried by default) 2) the current user doesn't have valid kerberos credentials This situation is quite common - as of now a sec=sys mount would use krb5i for the nfs_client's rpc_client and a user would hardly be faulted for not having run kinit. The solution is to use the machine cred when trying to use an integrity protected auth flavor for SECINFO_NO_NAME. Older servers may not support using the machine cred or an integrity protected auth flavor for SECINFO_NO_NAME in every circumstance, so we fall back to using the user's cred and the filesystem's auth flavor in this case. We run into another problem when running against linux nfs servers - they return NFS4ERR_WRONGSEC when using integrity auth flavor (unless the mount is also that flavor) even though that is not a valid error for SECINFO*. Even though it's against spec, handle WRONGSEC errors on SECINFO_NO_NAME by falling back to using the user cred and the filesystem's auth flavor. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-07NFS: nfs_compare_super shouldn't check the auth flavour unless 'sec=' was setTrond Myklebust
Also don't worry about obsolete mount flags... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-07NFSv4: Allow security autonegotiation for submountsTrond Myklebust
In cases where the parent super block was not mounted with a 'sec=' line, allow autonegotiation of security for the submounts. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>