void _req_may_be_done(struct drbd_request *req, struct bio_and_error *m)
{
const unsigned long s = req->rq_state;
struct drbd_conf *mdev = req->mdev;
int rw = req->master_bio ? bio_data_dir(req->master_bio) : WRITE;
if (s & RQ_NET_QUEUED)
return;
if (s & RQ_NET_PENDING)
return;
if (s & RQ_LOCAL_PENDING)
return;
if (req->master_bio) {
int ok = (s & RQ_LOCAL_OK) || (s & RQ_NET_OK);
int error = PTR_ERR(req->private_bio);
if (!hlist_unhashed(&req->collision))
hlist_del(&req->collision);
else
D_ASSERT((s & (RQ_NET_MASK & ~RQ_NET_DONE)) == 0);
if (rw == WRITE)
_about_to_complete_local_write(mdev, req);
_drbd_end_io_acct(mdev, req);
m->error = ok ? 0 : (error ?: -EIO);
m->bio = req->master_bio;
req->master_bio = NULL;
}
/* Helper for __req_mod().
* Set m->bio to the master bio, if it is fit to be completed,
* or leave it alone (it is initialized to NULL in __req_mod),
* if it has already been completed, or cannot be completed yet.
* If m->bio is set, the error status to be returned is placed in m->error.
*/
void _req_may_be_done(struct drbd_request *req, struct bio_and_error *m)
{
const unsigned long s = req->rq_state;
struct drbd_conf *mdev = req->mdev;
/* only WRITES may end up here without a master bio (on barrier ack) */
int rw = req->master_bio ? bio_data_dir(req->master_bio) : WRITE;
/* we must not complete the master bio, while it is
* still being processed by _drbd_send_zc_bio (drbd_send_dblock)
* not yet acknowledged by the peer
* not yet completed by the local io subsystem
* these flags may get cleared in any order by
* the worker,
* the receiver,
* the bio_endio completion callbacks.
*/
if (s & RQ_NET_QUEUED)
return;
if (s & RQ_NET_PENDING)
return;
if (s & RQ_LOCAL_PENDING)
return;
if (req->master_bio) {
/* this is data_received (remote read)
* or protocol C P_WRITE_ACK
* or protocol B P_RECV_ACK
* or protocol A "handed_over_to_network" (SendAck)
* or canceled or failed,
* or killed from the transfer log due to connection loss.
*/
/*
* figure out whether to report success or failure.
*
* report success when at least one of the operations succeeded.
* or, to put the other way,
* only report failure, when both operations failed.
*
* what to do about the failures is handled elsewhere.
* what we need to do here is just: complete the master_bio.
*
* local completion error, if any, has been stored as ERR_PTR
* in private_bio within drbd_endio_pri.
*/
int ok = (s & RQ_LOCAL_OK) || (s & RQ_NET_OK);
int error = PTR_ERR(req->private_bio);
/* remove the request from the conflict detection
* respective block_id verification hash */
if (!hlist_unhashed(&req->collision))
hlist_del(&req->collision);
else
D_ASSERT((s & (RQ_NET_MASK & ~RQ_NET_DONE)) == 0);
/* for writes we need to do some extra housekeeping */
if (rw == WRITE)
_about_to_complete_local_write(mdev, req);
/* Update disk stats */
_drbd_end_io_acct(mdev, req);
m->error = ok ? 0 : (error ?: -EIO);
m->bio = req->master_bio;
req->master_bio = NULL;
}
/* Helper for __req_mod().
* Set m->bio to the master bio, if it is fit to be completed,
* or leave it alone (it is initialized to NULL in __req_mod),
* if it has already been completed, or cannot be completed yet.
* If m->bio is set, the error status to be returned is placed in m->error.
*/
static
void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m)
{
const unsigned s = req->rq_state;
struct drbd_conf *mdev = req->w.mdev;
int rw;
int error, ok;
/* we must not complete the master bio, while it is
* still being processed by _drbd_send_zc_bio (drbd_send_dblock)
* not yet acknowledged by the peer
* not yet completed by the local io subsystem
* these flags may get cleared in any order by
* the worker,
* the receiver,
* the bio_endio completion callbacks.
*/
if ((s & RQ_LOCAL_PENDING && !(s & RQ_LOCAL_ABORTED)) ||
(s & RQ_NET_QUEUED) || (s & RQ_NET_PENDING) ||
(s & RQ_COMPLETION_SUSP)) {
dev_err(DEV, "drbd_req_complete: Logic BUG rq_state = 0x%x\n", s);
return;
}
if (!req->master_bio) {
dev_err(DEV, "drbd_req_complete: Logic BUG, master_bio == NULL!\n");
return;
}
rw = bio_rw(req->master_bio);
/*
* figure out whether to report success or failure.
*
* report success when at least one of the operations succeeded.
* or, to put the other way,
* only report failure, when both operations failed.
*
* what to do about the failures is handled elsewhere.
* what we need to do here is just: complete the master_bio.
*
* local completion error, if any, has been stored as ERR_PTR
* in private_bio within drbd_request_endio.
*/
ok = (s & RQ_LOCAL_OK) || (s & RQ_NET_OK);
error = PTR_ERR(req->private_bio);
/* remove the request from the conflict detection
* respective block_id verification hash */
if (!drbd_interval_empty(&req->i)) {
struct rb_root *root;
if (rw == WRITE)
root = &mdev->write_requests;
else
root = &mdev->read_requests;
drbd_remove_request_interval(root, req);
}
/* Before we can signal completion to the upper layers,
* we may need to close the current transfer log epoch.
* We are within the request lock, so we can simply compare
* the request epoch number with the current transfer log
* epoch number. If they match, increase the current_tle_nr,
* and reset the transfer log epoch write_cnt.
*/
if (rw == WRITE &&
req->epoch == atomic_read(&mdev->tconn->current_tle_nr))
start_new_tl_epoch(mdev->tconn);
/* Update disk stats */
_drbd_end_io_acct(mdev, req);
/* If READ failed,
* have it be pushed back to the retry work queue,
* so it will re-enter __drbd_make_request(),
* and be re-assigned to a suitable local or remote path,
* or failed if we do not have access to good data anymore.
*
* Unless it was failed early by __drbd_make_request(),
* because no path was available, in which case
* it was not even added to the transfer_log.
*
* READA may fail, and will not be retried.
*
* WRITE should have used all available paths already.
*/
if (!ok && rw == READ && !list_empty(&req->tl_requests))
req->rq_state |= RQ_POSTPONED;
if (!(req->rq_state & RQ_POSTPONED)) {
m->error = ok ? 0 : (error ?: -EIO);
m->bio = req->master_bio;
req->master_bio = NULL;
}
