ceph: Don't forget the 'up_read(&osdc->map_sem)' if met error.

CC: stable@vger.kernel.org
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Reviewed-by: Sage Weil <sage@inktank.com>
libceph: unregister request in __map_request failed and nofail == false

For nofail == false request, if __map_request failed, the caller does
cleanup work, like releasing the relative pages.  It doesn't make any sense
to retry this request.

CC: stable@vger.kernel.org
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Reviewed-by: Sage Weil <sage@inktank.com>
ceph: drop CAP_LINK_SHARED when sending "link" request to MDS

To handle "link" request, the MDS need to xlock inode's linklock,
which requires revoking any CAP_LINK_SHARED.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
ceph: wake up writer if vmtruncate work get blocked

To write data, the writer first acquires the i_mutex, then try getting
caps. The writer may sleep while holding the i_mutex. If the MDS revokes
Fb cap in this case, vmtruncate work can't do its job because i_mutex
is locked. We should wake up the writer and let it truncate the pages.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>