Before sending new flushsnap message, check if there are old
flushsnap messages that need to be re-sent. If there are, re-send
old messages first. This guarantees ordering of flushsnap messages.
Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Ensure that when writeback errors are marked that we report those to all
file descriptions that were open at the time of the error.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

These flags tell mds if there is pending capsnap explicitly.
Without this explicit notification, mds can only conclude if
client has pending capsnap. The method mds use is inefficient
and error-prone.
Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

The old 'approaching max_size' code expects MDS set max_size to
'2 * reported_size'. This is no longer true. The new code reports
file size when half of previous max_size increment has been used.
Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

The 'wanted max size' could be sent to inode's old auth mds, re-send
it to inode's new auth mds if necessary. Otherwise write syscall may
hang.
Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Have the client store and update the osdc epoch_barrier when a cap
message comes in with one.

When sending cap messages, send the epoch barrier as well. This allows
clients to inform servers that their released caps may not be used until
a particular OSD map epoch.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: N"Yan, Zheng” <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

- ask for a commit reply instead of an ack reply in
  __ceph_pool_perm_get()
- don't ask for both ack and commit replies in ceph_sync_write()
- since just only one reply is requested now, i_unsafe_writes list
  will always be empty -- kill ceph_sync_write_wait() and go back to
  a standard ->evict_inode()
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

__ceph_caps_mds_wanted() ignores caps from stale session. So the
return value of __ceph_caps_mds_wanted() can keep the same across
ceph_renew_caps(). This causes try_get_cap_refs() to keep calling
ceph_renew_caps(). The fix is ignore the session valid check for
the try_get_cap_refs() case. If session is stale, just let the
caps requester sleep.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

when flushing inode's auth cap changes, we need to move it into the
new auth cap session's cap_flushing list
Signed-off-by: NYan, Zheng <zyan@redhat.com>

user space may open/close single file frequently. It's not good
to send a clientcaps message to mds for each open/close syscall.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This removes the uses of ACCESS_ONCE in favor of READ_ONCE
Signed-off-by: NSeraphime Kirkovski <kirkseraph@gmail.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

If we have a parent inode reference already, then we don't need to
go back up the directory tree to find one.

Link: http://tracker.ceph.com/issues/18148Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Accessing d_parent requires some sort of locking or it could vanish
out from under us. Since we take the d_lock anyway, use that to fetch
d_parent and take a reference to it, and then use that reference to
call ceph_encode_inode_release.

Link: http://tracker.ceph.com/issues/18148Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Commit 5c341ee3 ("ceph: fix scheduler warning due to nested
blocking") causes infinite loop when process is interrupted.  Fix it.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

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

Add a flags parameter to send_cap_msg, so we can request expedited
service from the MDS when we know we'll be waiting on the result.

Set that flag in the case of try_flush_caps. The callers of that
function generally wait synchronously on the result, so it's beneficial
to ask the server to expedite it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

The userland ceph has MClientCaps at struct version 10. This brings the
kernel up the same version.

For now, all of the the new stuff is set to default values including
the flags field, which will be conditionally set in a later patch.

Note that we don't need to set the change_attr and btime to anything
since we aren't currently setting the feature flag. The MDS should
ignore those values.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

When we get to this many arguments, it's hard to work with positional
parameters. send_cap_msg is already at 25 arguments, with more needed.

Define a new args structure and pass a pointer to it to send_cap_msg.
Eventually it might make sense to embed one of these inside
ceph_cap_snap instead of tracking individual fields.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

Just for clarity. This part is inside the header, so it makes sense to
group it with the rest of the stuff in the header.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

For readahead/fadvise cases, caller of ceph_readpages does not
hold buffer capability. Pages can be added to page cache while
there is no buffer capability. This can cause data integrity
issue.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

try_get_cap_refs can be used as a condition in a wait_event* calls.
This is all fine until it has to call __ceph_do_pending_vmtruncate,
which in turn acquires the i_truncate_mutex. This leads to a situation
in which a task's state is !TASK_RUNNING and at the same time it's
trying to acquire a sleeping primitive. In essence a nested sleeping
primitives are being used. This causes the following warning:

WARNING: CPU: 22 PID: 11064 at kernel/sched/core.c:7631 __might_sleep+0x9f/0xb0()
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8109447d>] prepare_to_wait_event+0x5d/0x110
 ipmi_msghandler tcp_scalable ib_qib dca ib_mad ib_core ib_addr ipv6
CPU: 22 PID: 11064 Comm: fs_checker.pl Tainted: G           O    4.4.20-clouder2 #6
Hardware name: Supermicro X10DRi/X10DRi, BIOS 1.1a 10/16/2015
 0000000000000000 ffff8838b416fa88 ffffffff812f4409 ffff8838b416fad0
 ffffffff81a034f2 ffff8838b416fac0 ffffffff81052b46 ffffffff81a0432c
 0000000000000061 0000000000000000 0000000000000000 ffff88167bda54a0
Call Trace:
 [<ffffffff812f4409>] dump_stack+0x67/0x9e
 [<ffffffff81052b46>] warn_slowpath_common+0x86/0xc0
 [<ffffffff81052bcc>] warn_slowpath_fmt+0x4c/0x50
 [<ffffffff8109447d>] ? prepare_to_wait_event+0x5d/0x110
 [<ffffffff8109447d>] ? prepare_to_wait_event+0x5d/0x110
 [<ffffffff8107767f>] __might_sleep+0x9f/0xb0
 [<ffffffff81612d30>] mutex_lock+0x20/0x40
 [<ffffffffa04eea14>] __ceph_do_pending_vmtruncate+0x44/0x1a0 [ceph]
 [<ffffffffa04fa692>] try_get_cap_refs+0xa2/0x320 [ceph]
 [<ffffffffa04fd6f5>] ceph_get_caps+0x255/0x2b0 [ceph]
 [<ffffffff81094370>] ? wait_woken+0xb0/0xb0
 [<ffffffffa04f2c11>] ceph_write_iter+0x2b1/0xde0 [ceph]
 [<ffffffff81613f22>] ? schedule_timeout+0x202/0x260
 [<ffffffff8117f01a>] ? kmem_cache_free+0x1ea/0x200
 [<ffffffff811b46ce>] ? iput+0x9e/0x230
 [<ffffffff81077632>] ? __might_sleep+0x52/0xb0
 [<ffffffff81156147>] ? __might_fault+0x37/0x40
 [<ffffffff8119e123>] ? cp_new_stat+0x153/0x170
 [<ffffffff81198cfa>] __vfs_write+0xaa/0xe0
 [<ffffffff81199369>] vfs_write+0xa9/0x190
 [<ffffffff811b6d01>] ? set_close_on_exec+0x31/0x70
 [<ffffffff8119a056>] SyS_write+0x46/0xa0

This happens since wait_event_interruptible can interfere with the
mutex locking code, since they both fiddle with the task state.

Fix the issue by using the newly-added nested blocking infrastructure
in 61ada528 ("sched/wait: Provide infrastructure to deal with
nested blocking")

Link: https://lwn.net/Articles/628628/Signed-off-by: NNikolay Borisov <kernel@kyup.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

Add a 'wake' flag to ceph_cap_flush struct, which indicates if there
is someone waiting for it to finish. When getting flush ack message,
we check the 'wake' flag in corresponding ceph_cap_flush struct to
decide if we should wake up waiters. One corner case is that the
acked cap flush has 'wake' flags is set, but it is not the first one
on the flushing list. We do not wake up waiters in this case, set
'wake' flags of preceding ceph_cap_flush struct instead
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This patch devide __ceph_flush_snaps() into two stags. In the first
stage, __ceph_flush_snaps() assign snapcaps flush TIDs and add them
to cap flush lists. __ceph_flush_snaps() keeps holding the
i_ceph_lock in this stagge. So inode's auth cap can not change. In
the second stage, __ceph_flush_snaps() send flushsnap cap messages.
i_ceph_lock is unlocked before sending each cap message. If auth cap
changes in the middle, __ceph_flush_snaps() just stops. This is OK
because kick_flushing_inode_caps() will re-send flushsnap cap messages
to inode's new auth MDS.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

If ceph_check_caps() wants to send cap message to a recovering MDS,
make sure it kicks cap flushes first.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

make ceph_kick_flushing_caps() ignore inodes whose cap flushes
have already been re-sent by ceph_early_kick_flushing_caps()
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This patch includes following changes
- Assign flush tid to snapcap flush
- Remove session's s_cap_snaps_flushing list. Add inode to session's
  s_cap_flushing list instead. Inode is removed from the list when
  there is no pending snapcap flush or cap flush.
- make __kick_flushing_caps() re-send both snapcap flushes and cap
  flushes.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

We don't have requirement of searching cap flush by TID. In most cases,
we just need to know TID of the oldest cap flush. List is ideal for this
usage.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

Otherwise ceph_sync_write_unsafe() may access/modify freed inode.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Track usage count for individual fmode bit. This can reduce the
array size by half.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This patch adds codes that decode pool namespace information in
cap message and request reply. Pool namespace is saved in i_layout,
it will be passed to libceph when doing read/write.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Define new ceph_file_layout structure and rename old ceph_file_layout
to ceph_file_layout_legacy. This is preparation for adding namespace
to ceph_file_layout structure.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

There are several issues in fscache revalidation code.
- In ceph_revalidate_work(), fscache_invalidate() is called when
  fscache_check_consistency() return 0. This is complete wrong
  because 0 means cache is valid.
- Handle_cap_grant() calls ceph_queue_revalidate() if client
  already has CAP_FILE_CACHE. This code is confusing. Client
  should revalidate the cache each time it got CAP_FILE_CACHE
  anew.
- In Handle_cap_grant(), fscache_invalidate() is called if MDS
  revokes CAP_FILE_CACHE. This is inconsistency with the case
  that inode get evicted. In the later case, the cache is not
  discarded. Client may use the cache when inode is reloaded.

This patch moves the fscache revalidation into ceph_get_caps().
Client revalidates the cache after it gets CAP_FILE_CACHE.
i_rdcache_gen should keep constance while CAP_FILE_CACHE is
used. If i_fscache_gen is not equal to i_rdcache_gen, client
needs to check cache's consistency.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

ceph_fill_file_size() has already called ceph_fscache_invalidate()
if it return true.
Signed-off-by: NYan, Zheng <zyan@redhat.com>