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>

When ceph inode's i_head_snapc is NULL, __ceph_mark_dirty_caps()
accesses snap realm's cached_context. So we need take read lock
of snap_rwsem.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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>

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

ceph_add_cap() calls __check_cap_issue(), which clears directory
inode' complete flag. so we should set the complete flag for empty
directory should be set after calling ceph_add_cap().
Signed-off-by: NYan, Zheng <zyan@redhat.com>

remove all unsupported operations from {inode,file}_operations.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NYan, Zheng <zyan@redhat.com>

Request reply and cap message can contain inline data. add inline data
to the page cache if there is Fc cap.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Both ceph_update_writeable_page and ceph_setattr will verify file size
with max size ceph supported.
There are two caller for ceph_update_writeable_page, ceph_write_begin and
ceph_page_mkwrite. For ceph_write_begin, we have already verified the size in
generic_write_checks of ceph_write_iter; for ceph_page_mkwrite, we have no
chance to change file size when mmap. Likewise we have already verified the size
in inode_change_ok when we call ceph_setattr.
So let's remove the redundant code for max file size verification.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

Following sequence of events can happen.
  - Client releases an inode, queues cap release message.
  - A 'lookup' reply brings the same inode back, but the reply
    doesn't contain xattrs because MDS didn't receive the cap release
    message and thought client already has up-to-data xattrs.

The fix is force sending a getattr request to MDS if xattrs_version
is 0. The getattr mask is set to CEPH_STAT_CAP_XATTR, so MDS knows client
does not have xattr.
Signed-off-by: NYan, Zheng <zyan@redhat.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>

remember dirfrag's auth MDS when it's different from its parent inode's
auth MDS.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Move the code that update the i_fragtree into a separate function.
Also add simple probabilistic test to decide whether the i_fragtree
should be updated
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

So that ceph_add_cap() can be used while i_ceph_lock is locked.
This simplifies the code that handle cap import/export.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Cap message and request reply from non-auth MDS may carry stale
information (corresponding locks are in LOCK states) even they
have the newest inode version. So client should update inode fields
according to issued caps.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

When creating a file, ceph_set_dentry_offset() puts the new dentry
at the end of directory's d_subdirs, then set the dentry's offset
based on directory's max offset. The offset does not reflect the
real postion of the dentry in directory. Later readdir reply from
MDS may change the dentry's position/offset. This inconsistency
can cause missing/duplicate entries in readdir result if readdir
is partly satisfied by dcache_readdir().

The fix is clear directory's completeness after creating/renaming
file. It prevents later readdir from using dcache_readdir().

Fixes: http://tracker.ceph.com/issues/8025Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

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

Remove unsupported symlink operations.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com>

handle following sequence of events:
 - client releases a inode with i_max_size > 0. The release message
   is queued. (is not sent to the auth MDS)
 - a 'lookup' request reply from non-auth MDS returns the same inode.
 - client opens the inode in write mode. The version of inode trace
   in 'open' request reply is equal to the cached inode's version.
 - client requests new max size. The MDS ignores the request because
   it does not affect client's write range
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Use the newly introduced LOOKUPNAME MDS request to connect child
inode to its parent directory.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

The fsync(dirfd) only covers namespace operations, not inode updates.
We do not need to cover setattr variants or O_TRUNC.
Reported-by: NAl Viro <viro@xeniv.linux.org.uk>
Signed-off-by: NSage Weil <sage@inktank.com>
Reviewed-by: NYan, Zheng <zheng.z.yan@intel.com>

The merge of commit 7221fe4c ("ceph: add acl for cephfs") raced with
upstream changes in the generic POSIX ACL code (eg commit 2aeccbe9
"fs: add generic xattr_acl handlers" and others).

Some of the fallout was fixed in commit 4db658ea ("ceph: Fix up after
semantic merge conflict"), but it was incomplete: the set_acl
inode_operation wasn't getting set, and the prototype needed to be
adjusted a bit (it doesn't take a dentry anymore).
Signed-off-by: NSage Weil <sage@inktank.com>
Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The previous ceph-client merge resulted in ceph not even building,
because there was a merge conflict that wasn't visible as an actual data
conflict: commit 7221fe4c ("ceph: add acl for cephfs") added support
for POSIX ACL's into Ceph, but unluckily we also had the VFS tree change
a lot of the POSIX ACL helper functions to be much more helpful to
filesystems (see for example commits 2aeccbe9 "fs: add generic
xattr_acl handlers", 5bf3258f "fs: make posix_acl_chmod more useful"
and 37bc1539 "fs: make posix_acl_create more useful")

The reason this conflict wasn't obvious was many-fold: because it was a
semantic conflict rather than a data conflict, it wasn't visible in the
git merge as a conflict.  And because the VFS tree hadn't been in
linux-next, people hadn't become aware of it that way.  And because I
was at jury duty this morning, I was using my laptop and as a result not
doing constant "allmodconfig" builds.

Anyway, this fixes the build and generally removes a fair chunk of the
Ceph POSIX ACL support code, since the improved helpers seem to match
really well for Ceph too.  But I don't actually have any way to *test*
the end result, and I was really hoping for some ACK's for this.  Oh,
well.

Not compiling certainly doesn't make things easier to test, so I'm
committing this without the acks after having waited for four hours...
Plus it's what I would have done for the merge had I noticed the
semantic conflict..
Reported-by: NDave Jones <davej@redhat.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Guangliang Zhao <lucienchao@gmail.com>
Cc: Li Wang <li.wang@ubuntykylin.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Version 3 cap export message includes information about the imported
caps. It allows us to add the imported caps if the corresponding cap
import message still hasn't been received.

This allow us to handle situation that the importer MDS crashes and
the cap import message is missing.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

handle following sequence of events:

- non-auth MDS revokes Fc cap. queue invalidate work
- auth MDS issues Fc cap through request reply. i_rdcache_gen gets
  increased.
- invalidate work runs. it finds i_rdcache_revoking != i_rdcache_gen,
  so it does nothing.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

Signed-off-by: NGuangliang Zhao <lucienchao@gmail.com>
Reviewed-by: NLi Wang <li.wang@ubuntykylin.com>
Reviewed-by: NZheng Yan <zheng.z.yan@intel.com>

Positve dentry and corresponding inode are always accompanied in MDS reply.
So no need to keep inode in the cache after dropping all its aliases.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

commit b18825a7 (Put a small type field into struct dentry::d_flags)
put a type field into struct dentry::d_flags. __d_instantiate() set the
field by checking inode->i_mode. So we should initialize inode before
instantiating dentry when handling mds reply.

Fixes: http://tracker.ceph.com/issues/6930Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

If client has outdated directory fragments information, it may request
readdir an non-existent directory fragment. In this case, the MDS finds
an approximate directory fragment and sends its contents back to the
client. When receiving a reply with fragment that is different than the
requested one, the client need to reset the 'readdir offset'.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

If directory fragments change, fill_inode() inserts new frags into
the fragtree, but it does not remove outdated frags from the fragtree.
This patch fixes it.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

commit 6f60f889 (ceph: fix freeing inode vs removing session caps race)
introduced ceph_lookup_inode(). But there is already a ceph_find_inode()
which provides similar function. So remove ceph_lookup_inode(), use
ceph_find_inode() instead.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NAlex Elder <alex.elder@linary.org>
Reviewed-by: NSage Weil <sage@inktank.com>

Adding support for fscache to the Ceph filesystem. This would bring it to on
par with some of the other network filesystems in Linux (like NFS, AFS, etc...)

In order to mount the filesystem with fscache the 'fsc' mount option must be
passed.
Signed-off-by: NMilosz Tanski <milosz@adfin.com>
Signed-off-by: NSage Weil <sage@inktank.com>

I encountered below deadlock when running fsstress

wmtruncate work      truncate                 MDS
---------------  ------------------  --------------------------
                   lock i_mutex
                                      <- truncate file
lock i_mutex (blocked)
                                      <- revoking Fcb (filelock to MIX)
                   send request ->
                                         handle request (xlock filelock)

At the initial time, there are some dirty pages in the page cache.
When the kclient receives the truncate message, it reduces inode size
and creates some 'out of i_size' dirty pages. wmtruncate work can't
truncate these dirty pages because it's blocked by the i_mutex. Later
when the kclient receives the cap message that revokes Fcb caps, It
can't flush all dirty pages because writepages() only flushes dirty
pages within the inode size.

When the MDS handles the 'truncate' request from kclient, it waits
for the filelock to become stable. But the filelock is stuck in
unstable state because it can't finish revoking kclient's Fcb caps.

The truncate pagecache locking has already caused lots of trouble
for use. I think it's time simplify it by introducing a new mutex.
We use the new mutex to prevent concurrent truncate_inode_pages().
There is no need to worry about race between buffered write and
truncate_inode_pages(), because our "get caps" mechanism prevents
them from concurrent execution.
Reviewed-by: NSage Weil <sage@inktank.com>
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>