don't zero on short copies; if the page was uptodate it's just plain
wrong, and if it wasn't we'll be better off just returning 0 and
buggering off.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Splice read/write implementation changed recently. When using
generic_file_splice_read(), iov_iter with type == ITER_PIPE is
passed to filesystem's read_iter callback. But ceph_sync_read()
can't serve ITER_PIPE iov_iter correctly (ITER_PIPE iov_iter
expects pages from page cache).

Fixing ceph_sync_read() requires a big patch. So use default
splice read callback for now.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Fixes the following sparse warning:

fs/ceph/xattr.c:19:28: warning:
 symbol 'ceph_other_xattr_handler' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

    fs/ceph/super.c: In function ‘ceph_real_mount’:
    fs/ceph/super.c:818: warning: ‘root’ may be used uninitialized in this function

If s_root is already valid, dentry pointer root is never initialized,
and returned by ceph_real_mount(). This will cause a crash later when
the caller dereferences the pointer.

Fixes: ce2728aa ("ceph: avoid accessing / when mounting a subpath")
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

following sequence of events tigger the race

- client readdir frag 0* -> got item 'A'
- MDS merges frag 0* and frag 1*
- client send readdir request (frag 1*, offset 2, readdir_start 'A')
- MDS reply items (that are after item 'A') in frag *

Link: http://tracker.ceph.com/issues/17286Signed-off-by: NYan, Zheng <zyan@redhat.com>

In case __ceph_do_getattr returns an error and the retry_op in
ceph_read_iter is not READ_INLINE, then it's possible to invoke
__free_page on a page which is NULL, this naturally leads to a crash.
This can happen when, for example, a process waiting on a MDS reply
receives sigterm.

Fix this by explicitly checking whether the page is set or not.

Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: NNikolay Borisov <kernel@kyup.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

These inode operations are no longer used; remove them.
Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Using list_move() instead of list_del() + list_add().
Signed-off-by: NWei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

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

Accessing / causes failuire if the client has caps that restrict path
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

If O_DIRECT writes are racing with buffered writes, then
the call to invalidate_inode_pages2_range() can call ceph_releasepage()
on dirty pages.

Most filesystems hold inode_lock() across O_DIRECT writes so they do not
suffer this race, but cephfs deliberately drops the lock, and opens a window
for the race.

This race can be triggered with the generic/036 test from the xfstests
test suite.  It doesn't happen every time, but it does happen often.

As the possibilty is expected, remove the warning, and instead include
the PageDirty() status in the debug message.
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

This call can fail if there are dirty pages.  The preceding call to
filemap_write_and_wait_range() will normally remove dirty pages, but
as inode_lock() is not held over calls to ceph_direct_read_write(), it
could race with non-direct writes and pages could be dirtied
immediately after filemap_write_and_wait_range() returns

If there are dirty pages, they will be removed by the subsequent call
to truncate_inode_pages_range(), so having them here is not a problem.

If the 'ret' value is left holding an error, then in the async IO case
(aio_req is not NULL) the loop that would normally call
ceph_osdc_start_request() will see the error in 'ret' and abort all
requests.  This doesn't seem like correct behaviour.

So use separate 'ret2' instead of overloading 'ret'.
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

If start_page() fails to add a page to page cache or fails to send
OSD request. It should cal put_page() (instead of free_page()) for
relevant pages.

Besides, start_page() need to cancel fscache readpage if it fails
to send OSD request.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reported-by: NZhi Zhang <zhang.david2011@gmail.com>

current_fs_time() uses struct super_block* as an argument.
As per Linus's suggestion, this is changed to take struct
inode* as a parameter instead. This is because the function
is primarily meant for vfs inode timestamps.
Also the function was renamed as per Arnd's suggestion.

Change all calls to current_fs_time() to use the new
current_time() function instead. current_fs_time() will be
deleted.
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Generated patch:

sed -i "s/\.rename2\t/\.rename\t\t/" `git grep -wl rename2`
sed -i "s/\brename2\b/rename/g" `git grep -wl rename2`
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

This is trivial to do:

 - add flags argument to foo_rename()
 - check if flags is zero
 - assign foo_rename() to .rename2 instead of .rename

This doesn't mean it's impossible to support RENAME_NOREPLACE for these
filesystems, but it is not trivial, like for local filesystems.
RENAME_NOREPLACE must guarantee atomicity (i.e. it shouldn't be possible
for a file to be created on one host while it is overwritten by rename on
another host).

Filesystems converted:

9p, afs, ceph, coda, ecryptfs, kernfs, lustre, ncpfs, nfs, ocfs2, orangefs.

After this, we can get rid of the duplicate interfaces for rename.
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Howells <dhowells@redhat.com> [AFS]
Acked-by: NMike Marshall <hubcap@omnibond.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Mark Fasheh <mfasheh@suse.com>

inode_change_ok() will be resposible for clearing capabilities and IMA
extended attributes and as such will need dentry. Give it as an argument
to inode_change_ok() instead of an inode. Also rename inode_change_ok()
to setattr_prepare() to better relect that it does also some
modifications in addition to checks.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>

To avoid clearing of capabilities or security related extended
attributes too early, inode_change_ok() will need to take dentry instead
of inode. ceph_setattr() has the dentry easily available but
__ceph_setattr() is also called from ceph_set_acl() where dentry is not
easily available. Luckily that call path does not need inode_change_ok()
to be called anyway. So reorganize functions a bit so that
inode_change_ok() is called only from paths where dentry is available.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

References: CVE-2016-7097
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com>

Commit f3c4ebe6 ("ceph: using hash value to compose dentry offset")
modified "if (fpos_frag(new_pos) != fi->frag)" to "if (fi->frag |=
fpos_frag(new_pos))" in need_reset_readdir(), thus replacing a
comparison operator with an assignment one.

This looks like a typo which is reported by clang when building the
kernel with some warning flags:

    fs/ceph/dir.c:600:22: error: using the result of an assignment as a
    condition without parentheses [-Werror,-Wparentheses]
            } else if (fi->frag |= fpos_frag(new_pos)) {
                       ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
    fs/ceph/dir.c:600:22: note: place parentheses around the assignment
    to silence this warning
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^
                       (                             )
    fs/ceph/dir.c:600:22: note: use '!=' to turn this compound
    assignment into an inequality comparison
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^~
                                !=

Fixes: f3c4ebe6 ("ceph: using hash value to compose dentry offset")
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

pathbase is the base inode; set it to 0 if we've got no path.

Coverity-id: 146348
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

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

ceph_llseek does not correctly return NXIO errors because the 'out' path
always returns 'offset'.

Fixes: 06222e49 ("fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek")
Signed-off-by: NPhil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Ceph creates multiple caches with the SLAB_RECLAIMABLE flag set, so
that it can satisfy its internal needs. Inspecting the code shows that
most of the caches are indeed reclaimable since they are directly
related to the generic inode/dentry shrinkers. However, one of the
cache used to satisfy struct file is not reclaimable since its
entries are freed only when the last reference to the file is
dropped. If a heavily loaded node opens a lot of files it can
introduce non-trivial discrepancies between memory shown as reclaimable
and what is actually reclaimed when drop_caches is used.

Fix this by removing the reclaimable flag for the file's cache.
Signed-off-by: NNikolay Borisov <n.borisov.lkml@gmail.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>

This helps the recovering MDS to reconstruct the internal states that
tracking pending snapflush.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

To mount non-default filesytem, user currently needs to provide mds
namespace ID. This is inconvenience.

This patch makes user be able to mount filesystem by name. If user
wants to mount non-default filesystem. Client first subscribes to
fsmap.user. Subscribe to mdsmap.<ID> after getting ID of filesystem.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

We can now handle the snapshot cases under RCU, as well as the
non-snapshot case when we don't need to queue up a lease renewal
allow LOOKUP_RCU walks to proceed under those conditions.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

Under rcuwalk, we need to take extra care when dereferencing d_parent.
We want to do that once and pass a pointer to dentry_lease_is_valid.

Also, we must ensure that that function can handle the case where we're
racing with d_release. Check whether "di" is NULL under the d_lock, and
just return 0 if so.

Finally, we still need to kick off a renewal job if the lease is getting
close to expiration. If that's the case, then just drop out of rcuwalk
mode since that could block.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

To check for a valid dentry lease, we need to get at the
ceph_dentry_info. Under rcuwalk though, we may end up with a dentry that
is on its way to destruction. Since we need to take the d_lock in
dentry_lease_is_valid already, we can just ensure that we clear the
d_fsinfo pointer out under the same lock before destroying it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

Nothing calls it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>