sb->s_root can be null when umounting
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

No i_auth_cap means reconnecting to MDS was denied. So don't
add new dirty caps.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NNicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

use an atomic variable to track number of sessions, this can avoid block
operation inside wait loops.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

mark session as readonly and wake up all cap waiters.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NJeff Layton <jlayton@primarydata.com>
Acked-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

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/9945Signed-off-by: NJohn Spray <john.spray@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NMarkus Elfring <elfring@users.sourceforge.net>
[idryomov@redhat.com: squashed rbd.c hunk, changelog]
Signed-off-by: NIlya Dryomov <idryomov@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

...so that it can be used from the ceph debugfs
code when dumping session info.
Signed-off-by: NJohn Spray <john.spray@redhat.com>

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: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

this allow pagelist to present data that may be sent multiple times.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

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: NJohn Spray <john.spray@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

we may corrupt waiting list if a request in the waiting list is kicked.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

So the recovering MDS does not need to fetch these ununsed inodes during
cache rejoin. This may reduce MDS recovery time.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

__do_request() may unregister the request. So we should update
iterator 'p' before calling __do_request()
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

this makes __choose_mds() choose mds according caps
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Update the last pr_warning callsites in fs branch
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Sage Weil <sage@inktank.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NSage Weil <sage@inktank.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Preallocate buffer for readdir reply. Limit number of entries in
readdir reply according to the buffer size.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

send_mds_reconnect() may call discard_cap_releases() after all
release messages have been dropped by cleanup_cap_releases()
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

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: NSage Weil <sage@inktank.com>
Reviewed-by: NYan, Zheng <zheng.z.yan@intel.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

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: NYan, Zheng <zheng.z.yan@intel.com>

- 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: NYan, Zheng <zheng.z.yan@intel.com>