ceph: properly handle XATTR_CREATE and XATTR_REPLACE

return -EEXIST if XATTR_CREATE is set and xattr alread exists.
return -ENODATA if XATTR_REPLACE is set but xattr does not exist.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: remove xattr when null value is given to setxattr()

For the setxattr request, introduce a new flag CEPH_XATTR_REMOVE
to distinguish null value case from the zero-length value case.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: fix ceph_removexattr()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: fix ceph_set_acl()

If acl is equivalent to file mode permission bits, ceph_set_acl()
needs to remove any existing acl xattr. Use __ceph_setxattr() to
handle both setting and removing acl xattr cases, it doesn't return
-ENODATA when there is no acl xattr.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: add missing init_acl() for mkdir() and atomic_open()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: make ceph_forget_all_cached_acls() static inline

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Sage Weil <sage@inktank.com>
ceph: add acl, noacl options for cephfs mount

Make the 'acl' option dependent on having ACL support compiled in.  Make
the 'noacl' option work even without it so that one can always ask it to
be off and not error out on mount when it is not supported.

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Signed-off-by: Sage Weil <sage@inktank.com>
ceph: fix __dcache_readdir()

If directory is fragmented, readdir() read its dirfrags one by one.
After reading all dirfrags, the corresponding dentries are sorted in
(frag_t, off) order in the dcache. If dentries of a directory are all
cached, __dcache_readdir() can use the cached dentries to satisfy
readdir syscall. But when checking if a given dentry is after the
position of readdir, __dcache_readdir() compares numerical value of
frag_t directly. This is wrong, it should use ceph_frag_compare().

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
libceph: a per-osdc crush scratch buffer

With the addition of erasure coding support in the future, scratch
variable-length array in crush_do_rule_ary() is going to grow to at
least 200 bytes on average, on top of another 128 bytes consumed by
rawosd/osd arrays in the call chain.  Replace it with a buffer inside
struct osdmap and a mutex.  This shouldn't result in any contention,
because all osd requests were already serialized by request_mutex at
that point; the only unlocked caller was ceph_ioctl_get_dataloc().

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Merge git://github.com/ceph/ceph-client into for-linus