When readahead encounters file holes, osd reply returns error -ENOENT,
finish_read() skips adding pages to the the page cache. So readahead
does not work for file holes. The fix is adding zero pages to the
page cache when -ENOENT is returned.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

After forced umount, ceph_writepages_start() skips flushing dirty
pages. To make sure inode's reference count get dropped to zero,
we need to invalidate dirty pages.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This patch makes try_get_cap_refs() and __do_request() check
if the file system was forced umount, and return -EIO if it was.
This patch also adds a helper function to drops dirty caps and
wakes up blocking operation.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Before a page get locked, someone else can write data to the page
and increase the i_size. So we should re-check the i_size after
pages are locked.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

GFP_NOFS memory allocation is required for page writeback path.
But there is no need to use GFP_NOFS in syscall path and readpage
path
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

In most cases that snap context is needed, we are holding
reference of CEPH_CAP_FILE_WR. So we can set ceph inode's
i_head_snapc when getting the CEPH_CAP_FILE_WR reference,
and make codes get snap context from i_head_snapc. This makes
the code simpler.

Another benefit of this change is that we can handle snap
notification more elegantly. Especially when snap context
is updated while someone else is doing write. The old queue
cap_snap code may set cap_snap's context to ether the old
context or the new snap context, depending on if i_head_snapc
is set. The new queue capp_snap code always set cap_snap's
context to the old snap context.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Cached_context in ceph_snap_realm is directly accessed by
uninline_data() and get_pool_perm(). This is racy in theory.
both uninline_data() and get_pool_perm() do not modify existing
object, they only create new object. So we can pass the empty
snap context to them.  Unlike cached_context in ceph_snap_realm,
we do not need to protect the empty snap context.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

For CEPH_OSD_CMPXATTR_MODE_U64, OSD expects the u64 to be encoded
as string in object's xattr.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

When ceph_update_writeable_page fails (including -EAGAIN), it
unlocks (w/ unlock_page) the page but does not 'release'
(w/ page_cache_release) properly.

Upon error, properly set *pagep to NULL, indicating an error.
Signed-off-by: NTaesoo Kim <tsgatesv@gmail.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Now that no one is using rw, remove it completely.
Signed-off-by: NOmar Sandoval <osandov@osandov.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

when inode has inline data but its size > PAGE_SIZE (it was truncated
to larger size), previous direct read code return -EIO. This patch adds
code to return zeros for data whose offset > PAGE_SIZE.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Nobody uses it anymore.

[akpm@linux-foundation.org: fix filemap_xip.c]
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

len is size_t, should be printed with %zu.
Signed-off-by: NIlya Dryomov <idryomov@redhat.com>

Probably this code was syncing a lot more often then intended because
the do_sync variable wasn't set to zero.

Cc: stable@vger.kernel.org # v3.11+
Fixes: c62988ec ('ceph: avoid meaningless calling ceph_caps_revoking if sync_mode == WB_SYNC_ALL.')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NIlya Dryomov <idryomov@redhat.com>

Before any data write, convert inline data to normal data and set
i_inline_version to CEPH_INLINE_NONE. The OSD request that saves
inline data to object contains 3 operations (CMPXATTR, WRITE and
SETXATTR). It compares a xattr named 'inline_version' to prevent
old data overwrites newer data.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NYan, Zheng <zyan@redhat.com>

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: 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>

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: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NIlya Dryomov <idryomov@redhat.com>

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>

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>

If the return value of ceph_osdc_readpages() is not negative,
it is certainly greater than or equal to zero.

Remove the useless condition judgment and redundant braces.
Signed-off-by: NZhang Zhen <zhenzhang.zhang@huawei.com>
Reviewed-by: NYan, Zheng <zheng.z.yan@intel.com>

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

PAGE_CACHE_SIZE is unsigned long on all architectures, however size_t
is either unsigned int or unsigned long.  Rather than change format
strings, cast PAGE_CACHE_SIZE to size_t to be in line with dout()s in
ceph_page_mkwrite().

Cc: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Currently, if one new page allocated into fscache in readpage(), however,
with no data read into due to error encountered during reading from OSDs,
the slot in fscache is not uncached. This patch fixes this.
Signed-off-by: NLi Wang <liwang@ubuntukylin.com>
Reviewed-by: NMilosz Tanski <milosz@adfin.com>

Adds cap check to the page fault handler. The check prevents page
fault handler from adding new page to the page cache while Fcb caps
are being revoked. This solves Fc revoking hang in multiple clients
mmap IO workload.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Clean up if error occurred rather than going through normal process
Signed-off-by: NLi Wang <liwang@ubuntukylin.com>
Signed-off-by: NYunchuan Wen <yunchuanwen@ubuntukylin.com>
Signed-off-by: NSage Weil <sage@inktank.com>

If the length of data to be read in readpage() is exactly
PAGE_CACHE_SIZE, the original code does not flush d-cache
for data consistency after finishing reading. This patches fixes
this.
Signed-off-by: NLi Wang <liwang@ubuntukylin.com>
Signed-off-by: NSage Weil <sage@inktank.com>

ceph_osdc_readpages() returns number of bytes read, currently,
the code only allocate full-zero page into fscache, this patch
fixes this.
Signed-off-by: NLi Wang <liwang@ubuntukylin.com>
Reviewed-by: NMilosz Tanski <milosz@adfin.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Previous patch that allowed us to cleanup most of the issues with pages marked
as private_2 when calling ceph_readpages. However, there seams to be a case in
the error case clean up in start read that still trigers this from time to
time. I've only seen this one a couple times.

BUG: Bad page state in process petabucket  pfn:335b82
page:ffffea000cd6e080 count:0 mapcount:0 mapping:          (null) index:0x0
page flags: 0x200000000001000(private_2)
Call Trace:
 [<ffffffff81563442>] dump_stack+0x46/0x58
 [<ffffffff8112c7f7>] bad_page+0xc7/0x120
 [<ffffffff8112cd9e>] free_pages_prepare+0x10e/0x120
 [<ffffffff8112e580>] free_hot_cold_page+0x40/0x160
 [<ffffffff81132427>] __put_single_page+0x27/0x30
 [<ffffffff81132d95>] put_page+0x25/0x40
 [<ffffffffa02cb409>] ceph_readpages+0x2e9/0x6f0 [ceph]
 [<ffffffff811313cf>] __do_page_cache_readahead+0x1af/0x260
Signed-off-by: NMilosz Tanski <milosz@adfin.com>
Signed-off-by: NSage Weil <sage@inktank.com>

In some cases the ceph readapages code code bails without filling all the pages
already marked by fscache. When we return back to readahead code this causes
a BUG.
Signed-off-by: NMilosz Tanski <milosz@adfin.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>

Following we will begin to add memcg dirty page accounting around
__set_page_dirty_{buffers,nobuffers} in vfs layer, so we'd better use vfs interface to
avoid exporting those details to filesystems.

Since vfs set_page_dirty() should be called under page lock, here we don't need elaborate
codes to handle racy anymore, and two WARN_ON() are added to detect such exceptions.
Thanks very much for Sage and Yan Zheng's coaching!

I tested it in a two server's ceph environment that one is client and the other is
mds/osd/mon, and run the following fsx test from xfstests:

  ./fsx   1MB -N 50000 -p 10000 -l 1048576
  ./fsx  10MB -N 50000 -p 10000 -l 10485760
  ./fsx 100MB -N 50000 -p 10000 -l 104857600

The fsx does lots of mmap-read/mmap-write/truncate operations and the tests completed
successfully without triggering any of WARN_ON.
Signed-off-by: NSha Zhengju <handai.szj@taobao.com>
Reviewed-by: NSage Weil <sage@inktank.com>

The invalidatepage code bails if it encounters a non-zero page offset. The
current logic that does is non-obvious with multiple if statements.

This should be logically and functionally equivalent.
Signed-off-by: NMilosz Tanski <milosz@adfin.com>
Reviewed-by: NSage Weil <sage@inktank.com>

The early bug checks are moot because the VMA layer ensures those things.

1. It will not call invalidatepage unless PagePrivate (or PagePrivate2) are set
2. It will not call invalidatepage without taking a PageLock first.
3. Guantrees that the inode page is mapped.
Signed-off-by: NMilosz Tanski <milosz@adfin.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Signed-off-by: NJianpeng Ma <majianpeng@gmail.com>
Reviewed-by: NSage Weil <sage@inktank.com>

The client can receive truncate request from MDS at any time.
So the page writeback code need to get i_size, truncate_seq and
truncate_size atomically
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>