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: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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

No need to bifurcate wait now that we've got ceph_timeout_jiffies().
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NAlex Elder <elder@linaro.org>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

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: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

setfilelock requests can block for a long time, which can prevent
client from advancing its oldest tid.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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

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

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

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>

that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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>