| Message ID | 518ACCDD.6020802@inktank.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index dbfc44a..e417704 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -358,7 +358,7 @@ static ssize_t rbd_add(struct bus_type *bus, const char *buf, size_t count); static ssize_t rbd_remove(struct bus_type *bus, const char *buf, size_t count); -static int rbd_dev_image_probe(struct rbd_device *rbd_dev); +static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping); static struct bus_attribute rbd_bus_attrs[] = {
Any changes to parent images are immaterial to any mapped clone. So there is no need to have a watch event registered on header objects except for the header object of an image that is mapped. In fact, a watch request is a write operation, and we may only have read access to a parent image. We can't set up the watch request until we know the name of the header object though. So pass a flag to rbd_dev_image_probe() to indicate whether this probe is for a mapping or for a parent image. Change the second parameter to rbd_dev_header_watch_sync() be Boolean while we're at it. This resolves: http://tracker.ceph.com/issues/4941 Signed-off-by: Alex Elder <elder@inktank.com> --- drivers/block/rbd.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) __ATTR(add, S_IWUSR, NULL, rbd_add), @@ -2664,7 +2664,7 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data) * Request sync osd watch/unwatch. The value of "start" determines * whether a watch request is being initiated or torn down. */ -static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start) +static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start) { struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; struct rbd_obj_request *obj_request; @@ -2698,7 +2698,7 @@ static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start) rbd_dev->watch_request->osd_req); osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH, - rbd_dev->watch_event->cookie, 0, start); + rbd_dev->watch_event->cookie, 0, start ? 1 : 0); rbd_osd_req_format_write(obj_request); ret = rbd_obj_request_submit(osdc, obj_request); @@ -4549,7 +4549,7 @@ static int rbd_dev_probe_parent(struct rbd_device *rbd_dev) if (!parent) goto out_err; - ret = rbd_dev_image_probe(parent); + ret = rbd_dev_image_probe(parent, false); if (ret < 0) goto out_err; rbd_dev->parent = parent; @@ -4654,12 +4654,7 @@ static int rbd_dev_header_name(struct rbd_device *rbd_dev) static void rbd_dev_image_release(struct rbd_device *rbd_dev) { - int ret; - rbd_dev_unprobe(rbd_dev); - ret = rbd_dev_header_watch_sync(rbd_dev, 0); - if (ret) - rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret); kfree(rbd_dev->header_name); rbd_dev->header_name = NULL; rbd_dev->image_format = 0; @@ -4671,9 +4666,11 @@ static void rbd_dev_image_release(struct rbd_device *rbd_dev) /* * Probe for the existence of the header object for the given rbd - * device. + * device. If this image is the one being mapped (i.e., not a + * parent), initiate a watch on its header object before using that + * object to get detailed information about the rbd image. */ -static int rbd_dev_image_probe(struct rbd_device *rbd_dev) +static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping) { int ret; int tmp; @@ -4693,9 +4690,11 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev) if (ret) goto err_out_format; - ret = rbd_dev_header_watch_sync(rbd_dev, 1); - if (ret) - goto out_header_name; + if (mapping) { + ret = rbd_dev_header_watch_sync(rbd_dev, true); + if (ret) + goto out_header_name; + } if (rbd_dev->image_format == 1) ret = rbd_dev_v1_header_info(rbd_dev); @@ -4719,9 +4718,12 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev) err_out_probe: rbd_dev_unprobe(rbd_dev); err_out_watch: - tmp = rbd_dev_header_watch_sync(rbd_dev, 0); - if (tmp) - rbd_warn(rbd_dev, "unable to tear down watch request\n"); + if (mapping) { + tmp = rbd_dev_header_watch_sync(rbd_dev, false); + if (tmp) + rbd_warn(rbd_dev, "unable to tear down " + "watch request (%d)\n", tmp); + } out_header_name: kfree(rbd_dev->header_name); rbd_dev->header_name = NULL; @@ -4788,7 +4790,7 @@ static ssize_t rbd_add(struct bus_type *bus, rbdc = NULL; /* rbd_dev now owns this */ spec = NULL; /* rbd_dev now owns this */ - rc = rbd_dev_image_probe(rbd_dev); + rc = rbd_dev_image_probe(rbd_dev, true); if (rc < 0) goto err_out_rbd_dev; @@ -4910,10 +4912,13 @@ static ssize_t rbd_remove(struct bus_type *bus, spin_unlock_irq(&rbd_dev->lock); if (ret < 0) goto done; - ret = count; rbd_bus_del_dev(rbd_dev); + ret = rbd_dev_header_watch_sync(rbd_dev, false); + if (ret) + rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret); rbd_dev_image_release(rbd_dev); module_put(THIS_MODULE); + ret = count; done: mutex_unlock(&ctl_mutex);