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280 Commits (0a07fc8cd01b6838d999a5eacaa99fe90b8f768b)

Author SHA1 Message Date
Yan, Zheng 5e804ac482 ceph: don't invalidate page cache when inode is no longer used
ceph_check_caps() invalidate page cache when inode is not used
by any open file. This behaviour is not friendly for workload
that repeatly read files.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-11-02 23:36:48 +01:00
Arnd Bergmann 777d738a5e ceph: fix message length computation
create_request_message() computes the maximum length of a message,
but uses the wrong type for the time stamp: sizeof(struct timespec)
may be 8 or 16 depending on the architecture, while sizeof(struct
ceph_timespec) is always 8, and that is what gets put into the
message.

Found while auditing the uses of timespec for y2038 problems.

Fixes: b8e69066d8 ("ceph: include time stamp in every MDS request")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-11-02 23:36:47 +01:00
Jianpeng Ma 5fdb1389e1 ceph: cleanup use of ceph_msg_get
Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-09-08 23:14:29 +03:00
Brad Hubbard 1550d34e56 ceph: remove redundant test of head->safe and silence static analysis warnings
Signed-off-by: Brad Hubbard <bhubbard@redhat.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-09-08 23:14:29 +03:00
Yan, Zheng 48fec5d0a5 ceph: EIO all operations after forced umount
This patch makes try_get_cap_refs() and __do_request() check
if the file system was forced umount, and return -EIO if it was.
This patch also adds a helper function to drops dirty caps and
wakes up blocking operation.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-09-08 23:14:28 +03:00
Yan, Zheng 687265e5a8 ceph: switch some GFP_NOFS memory allocation to GFP_KERNEL
GFP_NOFS memory allocation is required for page writeback path.
But there is no need to use GFP_NOFS in syscall path and readpage
path

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:31 +03:00
Yan, Zheng f66fd9f095 ceph: pre-allocate data structure that tracks caps flushing
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:31 +03:00
Yan, Zheng e548e9b93d ceph: re-send flushing caps (which are revoked) in reconnect stage
if flushing caps were revoked, we should re-send the cap flush in
client reconnect stage. This guarantees that MDS processes the cap
flush message before issuing the flushing caps to other client.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:31 +03:00
Yan, Zheng 8310b08913 ceph: track pending caps flushing globally
So we know TID of the oldest pending caps flushing. Later patch will
send this information to MDS, so that MDS can trim its completed caps
flush list.

Tracking pending caps flushing globally also simplifies syncfs code.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:31 +03:00
Yan, Zheng 553adfd941 ceph: track pending caps flushing accurately
Previously we do not trace accurate TID for flushing caps. when
MDS failovers, we have no choice but to re-send all flushing caps
with a new TID. This can cause problem because MDS can has already
flushed some caps and has issued the same caps to other client.
The re-sent cap flush has a new TID, which makes MDS unable to
detect if it has already processed the cap flush.

This patch adds code to track pending caps flushing accurately.
When re-sending cap flush is needed, we use its original flush
TID.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:30 +03:00
Yan, Zheng 3e0708b990 ceph: ratelimit warn messages for MDS closes session
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:30 +03:00
Ilya Dryomov 5be7303477 ceph: simplify two mount_timeout sites
No need to bifurcate wait now that we've got ceph_timeout_jiffies().

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:29 +03:00
Ilya Dryomov a319bf56a6 libceph: store timeouts in jiffies, verify user input
There are currently three libceph-level timeouts that the user can
specify on mount: mount_timeout, osd_idle_ttl and osdkeepalive.  All of
these are in seconds and no checking is done on user input: negative
values are accepted, we multiply them all by HZ which may or may not
overflow, arbitrarily large jiffies then get added together, etc.

There is also a bug in the way mount_timeout=0 is handled.  It's
supposed to mean "infinite timeout", but that's not how wait.h APIs
treat it and so __ceph_open_session() for example will busy loop
without much chance of being interrupted if none of ceph-mons are
there.

Fix all this by verifying user input, storing timeouts capped by
msecs_to_jiffies() in jiffies and using the new ceph_timeout_jiffies()
helper for all user-specified waits to handle infinite timeouts
correctly.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
2015-06-25 11:49:29 +03:00
Yan, Zheng e8a7b8b12b ceph: exclude setfilelock requests when calculating oldest tid
setfilelock requests can block for a long time, which can prevent
client from advancing its oldest tid.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:29 +03:00
Yan, Zheng 745a8e3bcc ceph: don't pre-allocate space for cap release messages
Previously we pre-allocate cap release messages for each caps. This
wastes lots of memory when there are large amount of caps. This patch
make the code not pre-allocate the cap release messages. Instead,
we add the corresponding ceph_cap struct to a list when releasing a
cap. Later when flush cap releases is needed, we allocate the cap
release messages dynamically.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:29 +03:00
Yan, Zheng affbc19a68 ceph: make sure syncfs flushes all cap snaps
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:29 +03:00
Yan, Zheng 622f3e250f ceph: don't trim auth cap when there are cap snaps
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:28 +03:00
Yan, Zheng 10183a6955 ceph: check OSD caps before read/write
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-06-25 11:49:28 +03:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Yan, Zheng c0bd50e2ee ceph: fix null pointer dereference in send_mds_reconnect()
sb->s_root can be null when umounting

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-22 18:33:31 +03:00
Yan, Zheng 1c841a96b5 ceph: cleanup unsafe requests when reconnecting is denied
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-20 18:55:37 +03:00
Yan, Zheng a9f6eb6185 ceph: don't zero i_wrbuffer_ref when reconnecting is denied
remove_session_caps_cb() does not truncate dirty data in page
cache, but zeros i_wrbuffer_ref/i_wrbuffer_ref_head. This will
result negtive i_wrbuffer_ref/i_wrbuffer_ref_head

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-20 18:55:36 +03:00
Yan, Zheng 571ade336a ceph: don't mark dirty caps when there is no auth cap
No i_auth_cap means reconnecting to MDS was denied. So don't
add new dirty caps.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-20 18:55:36 +03:00
Nicholas Mc Guire 3563dbdd99 ceph: use msecs_to_jiffies for time conversion
This is only an API consolidation and should make things more readable
it replaces var * HZ / 1000 by msecs_to_jiffies(var).

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-20 17:30:22 +03:00
Yan, Zheng 6e6f09231a ceph: drop cap releases in requests composed before cap reconnect
These cap releases are stale because MDS will re-establish client
caps according to the cap reconnect messages.

Note: MDS can detect stale cap messages, so these stale cap
releases are harmless even we don't drop them.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-04-20 17:30:22 +03:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Linus Torvalds 4533f6e27a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph changes from Sage Weil:
 "On the RBD side, there is a conversion to blk-mq from Christoph,
  several long-standing bug fixes from Ilya, and some cleanup from
  Rickard Strandqvist.

  On the CephFS side there is a long list of fixes from Zheng, including
  improved session handling, a few IO path fixes, some dcache management
  correctness fixes, and several blocking while !TASK_RUNNING fixes.

  The core code gets a few cleanups and Chaitanya has added support for
  TCP_NODELAY (which has been used on the server side for ages but we
  somehow missed on the kernel client).

  There is also an update to MAINTAINERS to fix up some email addresses
  and reflect that Ilya and Zheng are doing most of the maintenance for
  RBD and CephFS these days.  Do not be surprised to see a pull request
  come from one of them in the future if I am unavailable for some
  reason"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (27 commits)
  MAINTAINERS: update Ceph and RBD maintainers
  libceph: kfree() in put_osd() shouldn't depend on authorizer
  libceph: fix double __remove_osd() problem
  rbd: convert to blk-mq
  ceph: return error for traceless reply race
  ceph: fix dentry leaks
  ceph: re-send requests when MDS enters reconnecting stage
  ceph: show nocephx_require_signatures and notcp_nodelay options
  libceph: tcp_nodelay support
  rbd: do not treat standalone as flatten
  ceph: fix atomic_open snapdir
  ceph: properly mark empty directory as complete
  client: include kernel version in client metadata
  ceph: provide seperate {inode,file}_operations for snapdir
  ceph: fix request time stamp encoding
  ceph: fix reading inline data when i_size > PAGE_SIZE
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_close_sessions)
  ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)
  rbd: fix error paths in rbd_dev_refresh()
  ...
2015-02-19 14:14:42 -08:00
Yan, Zheng 3de22be677 ceph: re-send requests when MDS enters reconnecting stage
So that MDS can check if any request is already completed and process
completed requests in clientreplay stage. When completed requests are
processed in clientreplay stage, MDS can avoid sending traceless
replies.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:40 +03:00
Yan, Zheng a6a5ce4f0d client: include kernel version in client metadata
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:39 +03:00
Yan, Zheng 1f041a89b4 ceph: fix request time stamp encoding
struct timespec uses 'long' to present second and nanosecond. 'long'
is 64 bits on 64bits machine. ceph MDS expects time stamp to be
encoded as struct ceph_timespec, which uses 'u32' to present second
and nanosecond.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:39 +03:00
Yan, Zheng 86d8f67b26 ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_close_sessions)
use an atomic variable to track number of sessions, this can avoid block
operation inside wait loops.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:38 +03:00
Yan, Zheng d3383a8e37 ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)
check_cap_flush() calls mutex_lock(), which may block. So we can't
use it as condition check function for wait_event();

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:38 +03:00
Yan, Zheng 982d6011bc ceph: improve reference tracking for snaprealm
When snaprealm is created, its initial reference count is zero.
But in some rare cases, the newly created snaprealm is not referenced
by anyone. This causes snaprealm with zero reference count not freed.

The fix is set reference count of newly snaprealm to 1. The reference
is return the function who requests to create the snaprealm. When the
function finishes its job, it releases the reference.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:38 +03:00
Yan, Zheng 03f4fcb028 ceph: handle SESSION_FORCE_RO message
mark session as readonly and wake up all cap waiters.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:37 +03:00
Jeff Layton c362781cad ceph: move spinlocking into ceph_encode_locks_to_buffer and ceph_count_locks
There is only a single call site for each of these functions, and the
caller takes the i_lock prior to calling them and drops it just
afterward. Move the spinlocking into the functions instead.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2015-01-16 15:09:25 -05:00
Yan, Zheng fb01d1f8b0 ceph: parse inline data in MClientReply and MClientCaps
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-12-17 20:09:52 +03:00
John Spray 7cfa0313d0 ceph: message versioning fixes
There were two places we were assigning version in host byte order
instead of network byte order.

Also in MSG_CLIENT_SESSION we weren't setting compat_version in the
header to reflect continued compatability with older MDSs.

Fixes: http://tracker.ceph.com/issues/9945

Signed-off-by: John Spray <john.spray@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-12-17 20:09:51 +03:00
Yan, Zheng 33d0733796 libceph: message signature support
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-12-17 20:09:50 +03:00
SF Markus Elfring e96a650a81 ceph, rbd: delete unnecessary checks before two function calls
The functions ceph_put_snap_context() and iput() test whether their
argument is NULL and then return immediately. Thus the test around the
call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[idryomov@redhat.com: squashed rbd.c hunk, changelog]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
2014-12-17 20:09:50 +03:00
Yan, Zheng 9280be24dc ceph: fix file lock interruption
When a lock operation is interrupted, current code sends a unlock request to
MDS to undo the lock operation. This method does not work as expected because
the unlock request can drop locks that have already been acquired.

The fix is use the newly introduced CEPH_LOCK_FCNTL_INTR/CEPH_LOCK_FLOCK_INTR
requests to interrupt blocked file lock request. These requests do not drop
locks that have alread been acquired, they only interrupt blocked file lock
request.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-12-17 20:09:49 +03:00
John Spray a687ecaf50 ceph: export ceph_session_state_name function
...so that it can be used from the ceph debugfs
code when dumping session info.

Signed-off-by: John Spray <john.spray@redhat.com>
2014-10-14 12:56:50 -07:00
Yan, Zheng 25e6bae356 ceph: use pagelist to present MDS request data
Current code uses page array to present MDS request data. Pages in the
array are allocated/freed by caller of ceph_mdsc_do_request(). If request
is interrupted, the pages can be freed while they are still being used by
the request message.

The fix is use pagelist to present MDS request data. Pagelist is
reference counted.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14 12:56:49 -07:00
Yan, Zheng e4339d28f6 libceph: reference counting pagelist
this allow pagelist to present data that may be sent multiple times.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14 12:56:48 -07:00
John Spray dbd0c8bf79 ceph: send client metadata to MDS
Implement version 2 of CEPH_MSG_CLIENT_SESSION syntax,
which includes additional client metadata to allow
the MDS to report on clients by user-sensible names
like hostname.

Signed-off-by: John Spray <john.spray@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2014-10-14 12:56:47 -07:00
Yan, Zheng 6cd3bcad0d ceph: move ceph_find_inode() outside the s_mutex
ceph_find_inode() may wait on freeing inode, using it inside the s_mutex
may cause deadlock. (the freeing inode is waiting for OSD read reply, but
dispatch thread is blocked by the s_mutex)

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14 21:03:39 +04:00
Yan, Zheng 03974e8177 ceph: make sure request isn't in any waiting list when kicking request.
we may corrupt waiting list if a request in the waiting list is kicked.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14 21:03:24 +04:00
Yan, Zheng 656e438294 ceph: protect kick_requests() with mdsc->mutex
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14 21:03:24 +04:00
Yan, Zheng 5d23371fdb ceph: trim unused inodes before reconnecting to recovering MDS
So the recovering MDS does not need to fetch these ununsed inodes during
cache rejoin. This may reduce MDS recovery time.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-10-14 21:03:22 +04:00
Yan, Zheng 282c105225 ceph: fix kick_requests()
__do_request() may unregister the request. So we should update
iterator 'p' before calling __do_request()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-08-07 14:30:00 +04:00
Yan, Zheng 51da8e8c6f ceph: reset r_resend_mds after receiving -ESTALE
this makes __choose_mds() choose mds according caps

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-07-14 10:49:15 +08:00
Yan, Zheng c5c9a0bf1b ceph: include time stamp in replayed MDS requests
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-07-08 15:08:46 +04:00
Linus Torvalds 6d87c225f5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
 "This has a mix of bug fixes and cleanups.

  Alex's patch fixes a rare race in RBD.  Ilya's patches fix an ENOENT
  check when a second rbd image is mapped and a couple memory leaks.
  Zheng fixes several issues with fragmented directories and multiple
  MDSs.  Josh fixes a spin/sleep issue, and Josh and Guangliang's
  patches fix setting and unsetting RBD images read-only.

  Naturally there are several other cleanups mixed in for good measure"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (23 commits)
  rbd: only set disk to read-only once
  rbd: move calls that may sleep out of spin lock range
  rbd: add ioctl for rbd
  ceph: use truncate_pagecache() instead of truncate_inode_pages()
  ceph: include time stamp in every MDS request
  rbd: fix ida/idr memory leak
  rbd: use reference counts for image requests
  rbd: fix osd_request memory leak in __rbd_dev_header_watch_sync()
  rbd: make sure we have latest osdmap on 'rbd map'
  libceph: add ceph_monc_wait_osdmap()
  libceph: mon_get_version request infrastructure
  libceph: recognize poolop requests in debugfs
  ceph: refactor readpage_nounlock() to make the logic clearer
  mds: check cap ID when handling cap export message
  ceph: remember subtree root dirfrag's auth MDS
  ceph: introduce ceph_fill_fragtree()
  ceph: handle cap import atomically
  ceph: pre-allocate ceph_cap struct for ceph_add_cap()
  ceph: update inode fields according to issued caps
  rbd: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
  ...
2014-06-12 23:06:23 -07:00
Fabian Frederick f3ae1b97be fs/ceph: replace pr_warning by pr_warn
Update the last pr_warning callsites in fs branch

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Sage Weil <sage@inktank.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:06 -07:00
Sage Weil b8e69066d8 ceph: include time stamp in every MDS request
We recently modified the client/MDS protocol to include a timestamp in the
client request.  This allows ctime updates to follow the client's clock
in most cases, which avoids subtle problems when clocks are out of sync
and timestamps are updated sometimes by the MDS clock (for most requests)
and sometimes by the client clock (for cap writeback).

Signed-off-by: Sage Weil <sage@inktank.com>
2014-06-06 09:30:00 +08:00
Yan, Zheng a56371d9d9 ceph: flush cap release queue when trimming session caps
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-04-04 21:08:26 -07:00
Yan, Zheng 54008399dc ceph: preallocate buffer for readdir reply
Preallocate buffer for readdir reply. Limit number of entries in
readdir reply according to the buffer size.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-04-04 21:08:22 -07:00
Yan, Zheng 00bd8edb86 ceph: fix null pointer dereference in discard_cap_releases()
send_mds_reconnect() may call discard_cap_releases() after all
release messages have been dropped by cleanup_cap_releases()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2014-04-04 21:07:17 -07:00
Sage Weil 844d87c332 ceph: do not assume r_old_dentry[_dir] always set together
Do not assume that r_old_dentry implies that r_old_dentry_dir is also
true.  Separate out the ref cleanup and make the debugs dump behave when
it is NULL.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-04-03 10:33:53 +08:00
Yan, Zheng 5d72d13c42 ceph: add open export target session helper
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-01-21 16:30:30 +08:00
Yan, Zheng 186e4f7a4b ceph: handle session flush message
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-01-21 13:29:33 +08:00
Yan, Zheng ca18bede04 ceph: handle -ESTALE reply
Send requests that operate on path to directory's auth MDS if
mode == USE_AUTH_MDS. Always retry using the auth MDS if got
-ESTALE reply from non-auth MDS. Also clean up the code that
handles auth MDS change.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-01-21 13:29:33 +08:00
Yan, Zheng 979abfdd5c ceph: fix trim caps
- don't trim auth cap if there are flusing caps
- don't trim auth cap if any 'write' cap is wanted
- allow trimming non-auth cap even if the inode is dirty

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2014-01-21 13:29:32 +08:00
Ilya Dryomov 12b4629a9f libceph: all features fields must be u64
In preparation for ceph_features.h update, change all features fields
from unsigned int/u32 to u64.  (ceph.git has ~40 feature bits at this
point.)

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-12-31 20:32:08 +02:00
Yan, Zheng fc55d2c944 ceph: wake up 'safe' waiters when unregistering request
We also need to wake up 'safe' waiters if error occurs or request
aborted. Otherwise sync(2)/fsync(2) may hang forever.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2013-11-23 11:01:05 -08:00
Yan, Zheng eb1b8af33c ceph: cleanup aborted requests when re-sending requests.
Aborted requests usually get cleared when the reply is received.
If MDS crashes, no reply will be received. So we need to cleanup
aborted requests when re-sending requests.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2013-11-23 11:01:04 -08:00
Yan, Zheng 99a9c273b9 ceph: handle race between cap reconnect and cap release
When a cap get released while composing the cap reconnect message.
We should skip queuing the release message if the cap hasn't been
added to the cap reconnect message.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-11-23 11:01:02 -08:00
Yan, Zheng 44c99757fa ceph: set caps count after composing cap reconnect message
It's possible that some caps get released while composing the cap
reconnect message.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-11-23 11:01:01 -08:00
Yan, Zheng a096b09aee ceph: queue cap release in __ceph_remove_cap()
call __queue_cap_release() in __ceph_remove_cap(), this avoids
acquiring s_cap_lock twice.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-11-23 11:00:59 -08:00
Yan, Zheng 81c6aea527 ceph: handle frag mismatch between readdir request and reply
If client has outdated directory fragments information, it may request
readdir an non-existent directory fragment. In this case, the MDS finds
an approximate directory fragment and sends its contents back to the
client. When receiving a reply with fragment that is different than the
requested one, the client need to reset the 'readdir offset'.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-09-30 14:49:53 -07:00
Yan, Zheng ed284c49f6 ceph: remove ceph_lookup_inode()
commit 6f60f889 (ceph: fix freeing inode vs removing session caps race)
introduced ceph_lookup_inode(). But there is already a ceph_find_inode()
which provides similar function. So remove ceph_lookup_inode(), use
ceph_find_inode() instead.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Alex Elder <alex.elder@linary.org>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-09-06 12:55:09 -07:00
Sage Weil ee3e542fec Merge remote-tracking branch 'linus/master' into testing 2013-08-15 11:11:45 -07:00
Yan, Zheng 6f60f88947 ceph: fix freeing inode vs removing session caps race
remove_session_caps() uses iterate_session_caps() to remove caps,
but iterate_session_caps() skips inodes that are being deleted.
So session->s_nr_caps can be non-zero after iterate_session_caps()
return.

We can fix the issue by waiting until deletions are complete.
__wait_on_freeing_inode() is designed for the job, but it is not
exported, so we use lookup inode function to access it.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2013-08-09 17:55:32 -07:00
Nathaniel Yazdani c338c07c51 ceph: fix null pointer dereference
When register_session() is given an out-of-range argument for mds,
ceph_mdsmap_get_addr() will return a null pointer, which would be given to
ceph_con_open() & be dereferenced, causing a kernel oops. This fixes bug #4685
in the Ceph bug tracker <http://tracker.ceph.com/issues/4685>.

Signed-off-by: Nathaniel Yazdani <n1ght.4nd.d4y@gmail.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-08-09 17:52:58 -07:00
Linus Torvalds 9a5889ae1c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
 "There is some follow-on RBD cleanup after the last window's code drop,
  a series from Yan fixing multi-mds behavior in cephfs, and then a
  sprinkling of bug fixes all around.  Some warnings, sleeping while
  atomic, a null dereference, and cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (36 commits)
  libceph: fix invalid unsigned->signed conversion for timespec encoding
  libceph: call r_unsafe_callback when unsafe reply is received
  ceph: fix race between cap issue and revoke
  ceph: fix cap revoke race
  ceph: fix pending vmtruncate race
  ceph: avoid accessing invalid memory
  libceph: Fix NULL pointer dereference in auth client code
  ceph: Reconstruct the func ceph_reserve_caps.
  ceph: Free mdsc if alloc mdsc->mdsmap failed.
  ceph: remove sb_start/end_write in ceph_aio_write.
  ceph: avoid meaningless calling ceph_caps_revoking if sync_mode == WB_SYNC_ALL.
  ceph: fix sleeping function called from invalid context.
  ceph: move inode to proper flushing list when auth MDS changes
  rbd: fix a couple warnings
  ceph: clear migrate seq when MDS restarts
  ceph: check migrate seq before changing auth cap
  ceph: fix race between page writeback and truncate
  ceph: reset iov_len when discarding cap release messages
  ceph: fix cap release race
  libceph: fix truncate size calculation
  ...
2013-07-09 12:39:10 -07:00
Al Viro 84d08fa888 helper for reading ->d_count
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-05 18:59:33 +04:00
majianpeng fb3101b6f0 ceph: Free mdsc if alloc mdsc->mdsmap failed.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-07-03 15:32:53 -07:00
Yan, Zheng 667ca05cd9 ceph: clear migrate seq when MDS restarts
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-07-03 15:32:49 -07:00
Yan, Zheng 3803da4963 ceph: reset iov_len when discarding cap release messages
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-07-03 15:32:47 -07:00
Jeff Layton 1c8c601a8c locks: protect most of the file_lock handling with i_lock
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.

->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.

Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.

For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the  blocked_list is done without dropping the
lock in between.

On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.

With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.

Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:42 +04:00
Jim Schutt 39be95e9c8 ceph: ceph_pagelist_append might sleep while atomic
Ceph's encode_caps_cb() worked hard to not call __page_cache_alloc()
while holding a lock, but it's spoiled because ceph_pagelist_addpage()
always calls kmap(), which might sleep.  Here's the result:

[13439.295457] ceph: mds0 reconnect start
[13439.300572] BUG: sleeping function called from invalid context at include/linux/highmem.h:58
[13439.309243] in_atomic(): 1, irqs_disabled(): 0, pid: 12059, name: kworker/1:1
    . . .
[13439.376225] Call Trace:
[13439.378757]  [<ffffffff81076f4c>] __might_sleep+0xfc/0x110
[13439.384353]  [<ffffffffa03f4ce0>] ceph_pagelist_append+0x120/0x1b0 [libceph]
[13439.391491]  [<ffffffffa0448fe9>] ceph_encode_locks+0x89/0x190 [ceph]
[13439.398035]  [<ffffffff814ee849>] ? _raw_spin_lock+0x49/0x50
[13439.403775]  [<ffffffff811cadf5>] ? lock_flocks+0x15/0x20
[13439.409277]  [<ffffffffa045e2af>] encode_caps_cb+0x41f/0x4a0 [ceph]
[13439.415622]  [<ffffffff81196748>] ? igrab+0x28/0x70
[13439.420610]  [<ffffffffa045e9f8>] ? iterate_session_caps+0xe8/0x250 [ceph]
[13439.427584]  [<ffffffffa045ea25>] iterate_session_caps+0x115/0x250 [ceph]
[13439.434499]  [<ffffffffa045de90>] ? set_request_path_attr+0x2d0/0x2d0 [ceph]
[13439.441646]  [<ffffffffa0462888>] send_mds_reconnect+0x238/0x450 [ceph]
[13439.448363]  [<ffffffffa0464542>] ? ceph_mdsmap_decode+0x5e2/0x770 [ceph]
[13439.455250]  [<ffffffffa0462e42>] check_new_map+0x352/0x500 [ceph]
[13439.461534]  [<ffffffffa04631ad>] ceph_mdsc_handle_map+0x1bd/0x260 [ceph]
[13439.468432]  [<ffffffff814ebc7e>] ? mutex_unlock+0xe/0x10
[13439.473934]  [<ffffffffa043c612>] extra_mon_dispatch+0x22/0x30 [ceph]
[13439.480464]  [<ffffffffa03f6c2c>] dispatch+0xbc/0x110 [libceph]
[13439.486492]  [<ffffffffa03eec3d>] process_message+0x1ad/0x1d0 [libceph]
[13439.493190]  [<ffffffffa03f1498>] ? read_partial_message+0x3e8/0x520 [libceph]
    . . .
[13439.587132] ceph: mds0 reconnect success
[13490.720032] ceph: mds0 caps stale
[13501.235257] ceph: mds0 recovery completed
[13501.300419] ceph: mds0 caps renewed

Fix it up by encoding locks into a buffer first, and when the number
of encoded locks is stable, copy that into a ceph_pagelist.

[elder@inktank.com: abbreviated the stack info a bit.]

Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Jim Schutt <jaschut@sandia.gov>
Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-17 12:45:48 -05:00
Jim Schutt c420276a53 ceph: add cpu_to_le32() calls when encoding a reconnect capability
In his review, Alex Elder mentioned that he hadn't checked that
num_fcntl_locks and num_flock_locks were properly decoded on the
server side, from a le32 over-the-wire type to a cpu type.
I checked, and AFAICS it is done; those interested can consult
    Locker::_do_cap_update()
in src/mds/Locker.cc and src/include/encoding.h in the Ceph server
code (git://github.com/ceph/ceph).

I also checked the server side for flock_len decoding, and I believe
that also happens correctly, by virtue of having been declared
__le32 in struct ceph_mds_cap_reconnect, in src/include/ceph_fs.h.

Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Jim Schutt <jaschut@sandia.gov>
Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-17 12:45:43 -05:00
Alex Elder 90af36022a libceph: add, don't set data for a message
Change the names of the functions that put data on a pagelist to
reflect that we're adding to whatever's already there rather than
just setting it to the one thing.  Currently only one data item is
ever added to a message, but that's about to change.

This resolves:
    http://tracker.ceph.com/issues/2770

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:18:34 -07:00
Sage Weil 27859f9773 libceph: wrap auth ops in wrapper functions
Use wrapper functions that check whether the auth op exists so that callers
do not need a bunch of conditional checks.  Simplifies the external
interface.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-01 21:17:14 -07:00
Sage Weil 0bed9b5c52 libceph: add update_authorizer auth method
Currently the messenger calls out to a get_authorizer con op, which will
create a new authorizer if it doesn't yet have one.  In the meantime, when
we rotate our service keys, the authorizer doesn't get updated.  Eventually
it will be rejected by the server on a new connection attempt and get
invalidated, and we will then rebuild a new authorizer, but this is not
ideal.

Instead, if we do have an authorizer, call a new update_authorizer op that
will verify that the current authorizer is using the latest secret.  If it
is not, we will build a new one that does.  This avoids the transient
failure.

This fixes one of the sorry sequence of events for bug

	http://tracker.ceph.com/issues/4282

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-01 21:17:13 -07:00
Yan, Zheng 2f276c5111 ceph: use i_release_count to indicate dir's completeness
Current ceph code tracks directory's completeness in two places.
ceph_readdir() checks i_release_count to decide if it can set the
I_COMPLETE flag in i_ceph_flags. All other places check the I_COMPLETE
flag. This indirection introduces locking complexity.

This patch adds a new variable i_complete_count to ceph_inode_info.
Set i_release_count's value to it when marking a directory complete.
By comparing the two variables, we know if a directory is complete

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
2013-05-01 21:17:07 -07:00
Alex Elder ebf18f4709 ceph: only set message data pointers if non-empty
Change it so we only assign outgoing data information for messages
if there is outgoing data to send.

This then allows us to add a few more (currently commented-out)
assertions.

This is related to:
    http://tracker.ceph.com/issues/4284

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01 21:16:41 -07:00
Alex Elder 27fa83852b libceph: isolate other message data fields
Define ceph_msg_data_set_pagelist(), ceph_msg_data_set_bio(), and
ceph_msg_data_set_trail() to clearly abstract the assignment of the
remaining data-related fields in a ceph message structure.  Use the
new functions in the osd client and mds client.

This partially resolves:
    http://tracker.ceph.com/issues/4263

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:16:40 -07:00
Alex Elder f1baeb2b9f libceph: set page info with byte length
When setting page array information for message data, provide the
byte length rather than the page count ceph_msg_data_set_pages().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:16:39 -07:00
Alex Elder 02afca6ca0 libceph: isolate message page field manipulation
Define a function ceph_msg_data_set_pages(), which more clearly
abstracts the assignment page-related fields for data in a ceph
message structure.  Use this new function in the osd client and mds
client.

Ideally, these fields would never be set more than once (with
BUG_ON() calls to guarantee that).  At the moment though the osd
client sets these every time it receives a message, and in the event
of a communication problem this can happen more than once.  (This
will be resolved shortly, but setting up these helpers first makes
it all a bit easier to work with.)

Rearrange the field order in a ceph_msg structure to group those
that are used to define the possible data payloads.

This partially resolves:
    http://tracker.ceph.com/issues/4263

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:16:38 -07:00
Alex Elder 54ae0756e3 libceph: no need for alignment for mds message
Currently, incoming mds messages never use page data, which means
there is no need to set the page_alignment field in the message.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01 21:16:20 -07:00
Alex Elder 53ded495c6 libceph: define mds_alloc_msg() method
The only user of the ceph messenger that doesn't define an alloc_msg
method is the mds client.  Define one, such that it works just like
it did before, and simplify ceph_con_in_msg_alloc() by assuming the
alloc_msg method is always present.

This and the next patch resolve:
    http://tracker.ceph.com/issues/4322

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01 21:16:19 -07:00
Alex Elder ec02a2f2ff libceph: kill ceph_msg->pagelist_count
The pagelist_count field is never actually used, so get rid of it.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:16:16 -07:00
Sage Weil 7971bd92ba ceph: revert commit 22cddde104
commit 22cddde104 breaks the atomicity of write operation, it also
introduces a deadlock between write and truncate.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>

Conflicts:
	fs/ceph/addr.c
2013-05-01 21:15:58 -07:00
Yan, Zheng a8673d61ad ceph: use I_COMPLETE inode flag instead of D_COMPLETE flag
commit c6ffe10015 moved the flag that tracks if the dcache contents
for a directory are complete to dentry. The problem is there are
lots of places that use ceph_dir_{set,clear,test}_complete() while
holding i_ceph_lock. but ceph_dir_{set,clear,test}_complete() may
sleep because they call dput().

This patch basically reverts that commit. For ceph_d_prune(), it's
called with both the dentry to prune and the parent dentry are
locked. So it's safe to access the parent dentry's d_inode and
clear I_COMPLETE flag.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01 21:14:33 -07:00
Yan, Zheng d40ee0dcc1 ceph: queue cap release when trimming cap
So the client will later send cap release message to MDS

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01 21:14:31 -07:00
Yan, Zheng 8a03449700 ceph: fix LSSNAP regression
commit 6e8575faa8 makes parse_reply_info_extra() return -EIO for LSSNAP

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01 21:14:30 -07:00
Alex Elder d4b515fa10 libceph: distinguish page array and pagelist count
Use distinct fields for tracking the number of pages in a message's
page array and in a message's page list.  Currently only one or the
other is used at a time, but that will be changing soon.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:14:28 -07:00
Linus Torvalds 1cf0209c43 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
 "A few groups of patches here.  Alex has been hard at work improving
  the RBD code, layout groundwork for understanding the new formats and
  doing layering.  Most of the infrastructure is now in place for the
  final bits that will come with the next window.

  There are a few changes to the data layout.  Jim Schutt's patch fixes
  some non-ideal CRUSH behavior, and a set of patches from me updates
  the client to speak a newer version of the protocol and implement an
  improved hashing strategy across storage nodes (when the server side
  supports it too).

  A pair of patches from Sam Lang fix the atomicity of open+create
  operations.  Several patches from Yan, Zheng fix various mds/client
  issues that turned up during multi-mds torture tests.

  A final set of patches expose file layouts via virtual xattrs, and
  allow the policies to be set on directories via xattrs as well
  (avoiding the awkward ioctl interface and providing a consistent
  interface for both kernel mount and ceph-fuse users)."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (143 commits)
  libceph: add support for HASHPSPOOL pool flag
  libceph: update osd request/reply encoding
  libceph: calculate placement based on the internal data types
  ceph: update support for PGID64, PGPOOL3, OSDENC protocol features
  ceph: update "ceph_features.h"
  libceph: decode into cpu-native ceph_pg type
  libceph: rename ceph_pg -> ceph_pg_v1
  rbd: pass length, not op for osd completions
  rbd: move rbd_osd_trivial_callback()
  libceph: use a do..while loop in con_work()
  libceph: use a flag to indicate a fault has occurred
  libceph: separate non-locked fault handling
  libceph: encapsulate connection backoff
  libceph: eliminate sparse warnings
  ceph: eliminate sparse warnings in fs code
  rbd: eliminate sparse warnings
  libceph: define connection flag helpers
  rbd: normalize dout() calls
  rbd: barriers are hard
  rbd: ignore zero-length requests
  ...
2013-02-28 17:43:09 -08:00
Eric W. Biederman ff3d004662 ceph: Convert struct ceph_mds_request to use kuid_t and kgid_t
Hold the uid and gid for a pending ceph mds request using the types
kuid_t and kgid_t.  When a request message is finally created convert
the kuid_t and kgid_t values into uids and gids in the initial user
namespace.

Cc: Sage Weil <sage@inktank.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-12 03:19:26 -08:00
Sam Lang 6e8575faa8 ceph: Check for created flag in response from mds
The mds now sends back a created inode if the create request
performed the create.  If the file already existed, no inode is
returned in the reply.  This allows ceph to set the created flag
in atomic_open so that permissions are properly checked in the case
that the file wasn't created by the create call to the mds.

To ensure compability with previous kernels, a feature for sending
back the inode in the create reply was added, so that the mds will
only send back the inode if the client indicates it supports the
feature.

Signed-off-by: Sam Lang <sam.lang@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2013-01-17 12:42:36 -06:00