ceph: fix sync read eof check deadlock
If a sync read gets a short result from the OSD, it may need to do a
getattr to see if it is short due to reaching end-of-file. The getattr
was being done while holding a reference to FILE_RD, which can lead to
a deadlock if the MDS is revoking that capability bit and can't process
the getattr until it does.
We fix this by setting a flag if EOF size validation is needed, and doing
the getattr in ceph_aio_read, after the RD cap ref is dropped. If the
read needs to be continued, we loop and continue traversing the file.
Signed-off-by: Sage Weil <sage@newdream.net>
1 file changed