rbd: remove fiemap use from import

On some kernels and filesystems fiemap can be racy and provide
incorrect data even after an fsync. Later we can use SEEK_HOLE and
SEEK_DATA, but for now just detect zero runs like we do with stdin.

Basically this adapts import from stdin to work in the case of a file
or block device, and gets rid of other cruft in the import that used
fiemap.

Fixes: #4388
Backport: bobtail
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
rbd: clean up do_import() a bit

Move declarations above error conditons so we can goto done almost
everywhere. Remove cpp_strerror printing, since it will be done by the
caller.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Merge branch 'wip-rbd-import' into next

Reviewed-by: Sage Weil <sage.weil@inktank.com>
mon/PaxosService: fix proposal waiter handling

- Cancel the propsal waiters with EAGAIN on election, etc.
- Drop the wakeup helper and open-code the one caller.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Joao Eduardo Luis <joao.luis@inktank.com>
mds: Handle ENODATA returned from getxattr

The osds might return ENODATA if we request an
xattr that doesn't exist.  In this case, we're
requesting the 'parent' xattr so that we can
remove all the forwarding pointers, but the xattr
may not have been written (which only happens on
log segment trim), so we don't assert here.

Signed-off-by: Sam Lang <sam.lang@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
ceph-disk-prepare: 'mkfs -t' instead of 'mkfs --type='

Older mkfs (el6) doesn't like --type=.

Fixes: #4495
Reported-by: Alexandre Maragone <alexandre.maragone@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>
Merge branch 'next'
Merge git://github.com/ceph/ceph