We re-run the loop but we don't re-set the attrs pointer back to NULL.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Alex Elder <elder@inktank.com>

This was an ill-conceived feature that has been removed from Ceph.  Do
this gracefully:

 - reject attempts to specify a preferred_osd via the ioctl
 - stop exposing this information via virtual xattrs
 - always fill in -1 for requests, in case we talk to an older server
 - don't calculate preferred_osd placements/pgids

Reviewed-by: Alex Elder <elder@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>

In ceph_vxattrcb_file_layout(), there is a check to determine
whether a preferred PG should be formatted into the output buffer.
That check assumes that a preferred PG number of 0 indicates "no
preference," but that is wrong.  No preference is indicated by a
negative (specifically, -1) PG number.

In addition, if that condition yields true, the preferred value
is formatted into a sized buffer, but the size consumed by the
earlier snprintf() call is not accounted for, opening up the
possibilty of a buffer overrun.

Finally, in ceph_vxattrcb_dir_rctime() where the nanoseconds part of
the time displayed did not include leading 0's, which led to
erroneous (sub-second portion of) time values being shown.

This fixes these three issues:
    http://tracker.newdream.net/issues/2155
    http://tracker.newdream.net/issues/2156
    http://tracker.newdream.net/issues/2157

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>

This patch just rearranges a few bits of code to make more
portions of ceph_setxattr() and ceph_removexattr() identical.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

All names defined in the directory and file virtual extended
attribute tables are constant, and the size of each is known at
compile time.  So there's no need to compute their length every
time any file's attribute is listed.

Record the length of each string and use it when needed to determine
the space need to represent them.  In addition, compute the
aggregate size of strings in each table just once at initialization
time.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

The names of the callback functions used for virtual extended
attributes are based only on the last component of the attribute
name.  Because of the way these are defined, this precludes allowing
a single (lowest) attribute name for different callbacks, dependent
on the type of file being operated on.  (For example, it might be
nice to support both "ceph.dir.layout" and "ceph.file.layout".)

Just change the callback names to avoid this problem.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

A struct ceph_vxattr_cb does not represent a callback at all, but
rather a virtual extended attribute itself.  Drop the "_cb" suffix
from its name to reflect that.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

Entries in the ceph virtual extended attribute tables all follow a
distinct pattern in their definition.  Enforce this pattern through
the use of a macro.

Also, a null name field signals the end of the table, so make that
be the first field in the ceph_vxattr_cb structure.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

Use symbolic constants to define the top-level prefix for "ceph."
extended attribute names.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

All callers of ceph_match_vxattr() determine what to pass as the
first argument by calling ceph_inode_vxattrs(inode).  Just do that
inside ceph_match_vxattr() itself, changing it to take an inode
rather than the vxattr pointer as its first argument.

Also ensure the function works correctly for an empty table (i.e.,
containing only a terminating null entry).

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>