linux-stable.git/fs/ceph/dir.c, branch linux-4.7.y

ceph: do not modify fi->frag in need_reset_readdir()

2016-10-07T13:21:26+00:00

commit 0f5aa88a7bb28b73253fb42b3df8202142769f39 upstream.

Commit f3c4ebe65ea1 ("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: f3c4ebe65ea1 ("ceph: using hash value to compose dentry offset")
Signed-off-by: Nicolas Iooss 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2016-05-26T21:10:32+00:00

Pull Ceph updates from Sage Weil:
 "This changeset has a few main parts:

   - Ilya has finished a huge refactoring effort to sync up the
     client-side logic in libceph with the user-space client code, which
     has evolved significantly over the last couple years, with lots of
     additional behaviors (e.g., how requests are handled when cluster
     is full and transitions from full to non-full).

     This structure of the code is more closely aligned with userspace
     now such that it will be much easier to maintain going forward when
     behavior changes take place.  There are some locking improvements
     bundled in as well.

   - Zheng adds multi-filesystem support (multiple namespaces within the
     same Ceph cluster)

   - Zheng has changed the readdir offsets and directory enumeration so
     that dentry offsets are hash-based and therefore stable across
     directory fragmentation events on the MDS.

   - Zheng has a smorgasbord of bug fixes across fs/ceph"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (71 commits)
  ceph: fix wake_up_session_cb()
  ceph: don't use truncate_pagecache() to invalidate read cache
  ceph: SetPageError() for writeback pages if writepages fails
  ceph: handle interrupted ceph_writepage()
  ceph: make ceph_update_writeable_page() uninterruptible
  libceph: make ceph_osdc_wait_request() uninterruptible
  ceph: handle -EAGAIN returned by ceph_update_writeable_page()
  ceph: make fault/page_mkwrite return VM_FAULT_OOM for -ENOMEM
  ceph: block non-fatal signals for fault/page_mkwrite
  ceph: make logical calculation functions return bool
  ceph: tolerate bad i_size for symlink inode
  ceph: improve fragtree change detection
  ceph: keep leaf frag when updating fragtree
  ceph: fix dir_auth check in ceph_fill_dirfrag()
  ceph: don't assume frag tree splits in mds reply are sorted
  ceph: fix inode reference leak
  ceph: using hash value to compose dentry offset
  ceph: don't forbid marking directory complete after forward seek
  ceph: record 'offset' for each entry of readdir result
  ceph: define 'end/complete' in readdir reply as bit flags
  ...

ceph: make logical calculation functions return bool

2016-05-25T23:15:39+00:00

This patch makes serverl logical caculation functions return bool to
improve readability due to these particular functions only using 0/1
as their return value.

No functional change.

Signed-off-by: Zhang Zhuoyu

ceph: using hash value to compose dentry offset

2016-05-25T23:15:36+00:00

If MDS sorts dentries in dirfrag in hash order, we use hash value to
compose dentry offset. dentry offset is:

  (0xff << 52) | ((24 bits hash) << 28) |
  (the nth entry hash hash collision)

This offset is stable across directory fragmentation. This alos means
there is no need to reset readdir offset if directory get fragmented
in the middle of readdir.

Signed-off-by: Yan, Zheng

ceph: don't forbid marking directory complete after forward seek

2016-05-25T23:15:36+00:00

Forward seek within same frag does not update fi->last_name, it will
not affect contents of later readdir reply. So there is no need to
forbid marking directory complete

Signed-off-by: Yan, Zheng

ceph: record 'offset' for each entry of readdir result

2016-05-25T23:15:35+00:00

This is preparation for using hash value as dentry 'offset'

Signed-off-by: Yan, Zheng

ceph: define 'end/complete' in readdir reply as bit flags

2016-05-25T23:15:35+00:00

Set a flag in readdir request, which indicates that client interprets
'end/complete' as bit flags. So that mds can reply additional flags in
readdir reply.

Signed-off-by: Yan, Zheng

ceph: define struct for dir entry in readdir reply

2016-05-25T23:15:34+00:00

This avoids defining multiple arrays for entries in readdir reply

Signed-off-by: Yan, Zheng

ceph: simplify 'offset in frag'

2016-05-25T23:15:34+00:00

don't distinguish leftmost frag from other frags. always use 2 as
first entry's offset.

Signed-off-by: Yan, Zheng

ceph: remove unnecessary checks in __dcache_readdir

2016-05-25T23:15:34+00:00

we never add snapdir and the hidden .ceph dir into readdir cache

Signed-off-by: Yan, Zheng