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>
libceph: nuke ceph_kvfree()

Use kvfree() from linux/mm.h instead, which is identical.  Also fix the
ceph_buffer comment: we will allocate with kmalloc() up to 32k - the
value of PAGE_ALLOC_COSTLY_ORDER, but that really is just an
implementation detail so don't mention it at all.

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
ceph: introduce a new inode flag indicating if cached dentries are ordered

After creating/deleting/renaming file, offsets of sibling dentries may
change. So we can not use cached dentries to satisfy readdir. But we can
still use the cached dentries to conclude -ENOENT for lookup.

This patch introduces a new inode flag indicating if child dentries are
ordered. The flag is set at the same time marking a directory complete.
After creating/deleting/renaming file, we clear the flag on directory
inode. This prevents ceph_readdir() from using cached dentries to satisfy
readdir syscall.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
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>
libceph: store session key in cephx authorizer

Session key is required when calculating message signature. Save the session
key in authorizer, this avoid lookup ticket handler for each message

Signed-off-by: Yan, Zheng <zyan@redhat.com>
libceph: message signature support

Signed-off-by: Yan, Zheng <zyan@redhat.com>
libceph: update ceph_msg_header structure

2 bytes of what was reserved space is now used by userspace for the
compat_version field.

Signed-off-by: John Spray <john.spray@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
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>
ceph: introduce global empty snap context

Current snaphost code does not properly handle moving inode from one
empty snap realm to another empty snap realm. After changing inode's
snap realm, some dirty pages' snap context can be not equal to inode's
i_head_snap. This can trigger BUG() in ceph_put_wrbuffer_cap_refs()

The fix is introduce a global empty snap context for all empty snap
realm. This avoids triggering the BUG() for filesystem with no snapshot.

Fixes: http://tracker.ceph.com/issues/9928

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
libceph: require cephx message signature by default

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
ceph: remove unused stringification macros

These were used to report git versions a long time ago.

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
rbd: don't treat CEPH_OSD_OP_DELETE as extent op

CEPH_OSD_OP_DELETE is not an extent op, stop treating it as such.  This
sneaked in with discard patches - it's one of the three osd ops (the
other two are CEPH_OSD_OP_TRUNCATE and CEPH_OSD_OP_ZERO) that discard
is implemented with.

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>
libceph: add SETXATTR/CMPXATTR osd operations support

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
libceph: add CREATE osd operation support

Add CEPH_OSD_OP_CREATE support.  Also change libceph to not treat
CEPH_OSD_OP_DELETE as an extent op and add an assert to that end.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
libceph: specify position of extent operation

allow specifying position of extent operation in multi-operations
osd request. This is required for cephfs to convert inline data to
normal data (compare xattr, then write object).

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
ceph: parse inline data in MClientReply and MClientCaps

Signed-off-by: Yan, Zheng <zyan@redhat.com>
ceph: add inline data to pagecache

Request reply and cap message can contain inline data. add inline data
to the page cache if there is Fc cap.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
ceph: use getattr request to fetch inline data

Add a new parameter 'locked_page' to ceph_do_getattr(). If inline data
in getattr reply will be copied to the page.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
ceph: fetch inline data when getting Fcr cap refs

we can't use getattr to fetch inline data after getting Fcr caps,
because it can cause deadlock. The solution is try bringing inline
data to page cache when not holding any cap, and hope the inline
data page is still there after getting the Fcr caps. If the page
is still there, pin it in page cache for later IO.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
ceph: sync read inline data

we can't use getattr to fetch inline data while holding Fr cap,
because it can cause deadlock. If we need to sync read inline data,
drop cap refs first, then use getattr to fetch inline data.

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