| Message ID | 50E60990.90109@inktank.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/03/2013 02:43 PM, Alex Elder wrote: > Now that a big hunk in the middle of rbd_rq_fn() has been moved > into its own routine we can simplify it a little more. > > Signed-off-by: Alex Elder <elder@inktank.com> > --- Reviewed-by: Josh Durgin <josh.durgin@inktank.com> > drivers/block/rbd.c | 50 > +++++++++++++++++++++++--------------------------- > 1 file changed, 23 insertions(+), 27 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index 88b9b2e..0a35c34 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -1647,53 +1647,49 @@ static int rbd_dev_do_request(struct request *rq, > static void rbd_rq_fn(struct request_queue *q) > { > struct rbd_device *rbd_dev = q->queuedata; > + bool read_only = rbd_dev->mapping.read_only; > struct request *rq; > > while ((rq = blk_fetch_request(q))) { > - struct bio *bio; > - bool do_write; > - unsigned int size; > - u64 ofs; > - struct ceph_snap_context *snapc; > + struct ceph_snap_context *snapc = NULL; > int result; > > dout("fetched request\n"); > > - /* filter out block requests we don't understand */ > + /* Filter out block requests we don't understand */ > + > if ((rq->cmd_type != REQ_TYPE_FS)) { > __blk_end_request_all(rq, 0); > continue; > } > + spin_unlock_irq(q->queue_lock); > > - /* deduce our operation (read, write) */ > - do_write = (rq_data_dir(rq) == WRITE); > - if (do_write && rbd_dev->mapping.read_only) { > - __blk_end_request_all(rq, -EROFS); > - continue; > - } > + /* Stop writes to a read-only device */ > > - spin_unlock_irq(q->queue_lock); > + result = -EROFS; > + if (read_only && rq_data_dir(rq) == WRITE) > + goto out_end_request; > + > + /* Grab a reference to the snapshot context */ > > down_read(&rbd_dev->header_rwsem); > + if (rbd_dev->exists) { > + snapc = ceph_get_snap_context(rbd_dev->header.snapc); > + rbd_assert(snapc != NULL); > + } > + up_read(&rbd_dev->header_rwsem); > > - if (!rbd_dev->exists) { > + if (!snapc) { > rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); > - up_read(&rbd_dev->header_rwsem); > dout("request for non-existent snapshot"); > - spin_lock_irq(q->queue_lock); > - __blk_end_request_all(rq, -ENXIO); > - continue; > + result = -ENXIO; > + goto out_end_request; > } > > - snapc = ceph_get_snap_context(rbd_dev->header.snapc); > - > - up_read(&rbd_dev->header_rwsem); > - > - size = blk_rq_bytes(rq); > - ofs = blk_rq_pos(rq) * SECTOR_SIZE; > - bio = rq->bio; > - > - result = rbd_dev_do_request(rq, rbd_dev, snapc, ofs, size, bio); > + result = rbd_dev_do_request(rq, rbd_dev, snapc, > + blk_rq_pos(rq) * SECTOR_SIZE, > + blk_rq_bytes(rq), rq->bio); > +out_end_request: > ceph_put_snap_context(snapc); > spin_lock_irq(q->queue_lock); > if (result < 0) > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 88b9b2e..0a35c34 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1647,53 +1647,49 @@ static int rbd_dev_do_request(struct request *rq, static void rbd_rq_fn(struct request_queue *q) { struct rbd_device *rbd_dev = q->queuedata; + bool read_only = rbd_dev->mapping.read_only; struct request *rq; while ((rq = blk_fetch_request(q))) { - struct bio *bio; - bool do_write; - unsigned int size; - u64 ofs; - struct ceph_snap_context *snapc; + struct ceph_snap_context *snapc = NULL; int result; dout("fetched request\n"); - /* filter out block requests we don't understand */ + /* Filter out block requests we don't understand */ + if ((rq->cmd_type != REQ_TYPE_FS)) { __blk_end_request_all(rq, 0); continue; } + spin_unlock_irq(q->queue_lock); - /* deduce our operation (read, write) */ - do_write = (rq_data_dir(rq) == WRITE); - if (do_write && rbd_dev->mapping.read_only) { - __blk_end_request_all(rq, -EROFS); - continue; - } + /* Stop writes to a read-only device */ - spin_unlock_irq(q->queue_lock); + result = -EROFS; + if (read_only && rq_data_dir(rq) == WRITE) + goto out_end_request; + + /* Grab a reference to the snapshot context */ down_read(&rbd_dev->header_rwsem); + if (rbd_dev->exists) { + snapc = ceph_get_snap_context(rbd_dev->header.snapc); + rbd_assert(snapc != NULL); + } + up_read(&rbd_dev->header_rwsem); - if (!rbd_dev->exists) { + if (!snapc) { rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); - up_read(&rbd_dev->header_rwsem); dout("request for non-existent snapshot"); - spin_lock_irq(q->queue_lock); - __blk_end_request_all(rq, -ENXIO); - continue; + result = -ENXIO; + goto out_end_request; } - snapc = ceph_get_snap_context(rbd_dev->header.snapc); - - up_read(&rbd_dev->header_rwsem); - - size = blk_rq_bytes(rq); - ofs = blk_rq_pos(rq) * SECTOR_SIZE; - bio = rq->bio; - - result = rbd_dev_do_request(rq, rbd_dev, snapc, ofs, size, bio); + result = rbd_dev_do_request(rq, rbd_dev, snapc, + blk_rq_pos(rq) * SECTOR_SIZE, + blk_rq_bytes(rq), rq->bio); +out_end_request: ceph_put_snap_context(snapc); spin_lock_irq(q->queue_lock); if (result < 0)
Now that a big hunk in the middle of rbd_rq_fn() has been moved into its own routine we can simplify it a little more. Signed-off-by: Alex Elder <elder@inktank.com> --- drivers/block/rbd.c | 50 +++++++++++++++++++++++--------------------------- 1 file changed, 23 insertions(+), 27 deletions(-)