diff options
Diffstat (limited to 'drivers/block/rbd.c')
| -rw-r--r-- | drivers/block/rbd.c | 48 |
1 files changed, 27 insertions, 21 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 34898d53395b..275a7dc2b06c 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1366,6 +1366,14 @@ static bool obj_request_exists_test(struct rbd_obj_request *obj_request) return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0; } +static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request) +{ + struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev; + + return obj_request->img_offset < + round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header)); +} + static void rbd_obj_request_get(struct rbd_obj_request *obj_request) { dout("%s: obj %p (was %d)\n", __func__, obj_request, @@ -1382,6 +1390,13 @@ static void rbd_obj_request_put(struct rbd_obj_request *obj_request) kref_put(&obj_request->kref, rbd_obj_request_destroy); } +static void rbd_img_request_get(struct rbd_img_request *img_request) +{ + dout("%s: img %p (was %d)\n", __func__, img_request, + atomic_read(&img_request->kref.refcount)); + kref_get(&img_request->kref); +} + static bool img_request_child_test(struct rbd_img_request *img_request); static void rbd_parent_request_destroy(struct kref *kref); static void rbd_img_request_destroy(struct kref *kref); @@ -1911,32 +1926,26 @@ static void rbd_dev_parent_put(struct rbd_device *rbd_dev) * If an image has a non-zero parent overlap, get a reference to its * parent. * - * We must get the reference before checking for the overlap to - * coordinate properly with zeroing the parent overlap in - * rbd_dev_v2_parent_info() when an image gets flattened. We - * drop it again if there is no overlap. - * * Returns true if the rbd device has a parent with a non-zero * overlap and a reference for it was successfully taken, or * false otherwise. */ static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) { - int counter; + int counter = 0; if (!rbd_dev->parent_spec) return false; - counter = atomic_inc_return_safe(&rbd_dev->parent_ref); - if (counter > 0 && rbd_dev->parent_overlap) - return true; - - /* Image was flattened, but parent is not yet torn down */ + down_read(&rbd_dev->header_rwsem); + if (rbd_dev->parent_overlap) + counter = atomic_inc_return_safe(&rbd_dev->parent_ref); + up_read(&rbd_dev->header_rwsem); if (counter < 0) rbd_warn(rbd_dev, "parent reference overflow\n"); - return false; + return counter > 0; } /* @@ -2128,6 +2137,7 @@ static void rbd_img_obj_callback(struct rbd_obj_request *obj_request) img_request->next_completion = which; out: spin_unlock_irq(&img_request->completion_lock); + rbd_img_request_put(img_request); if (!more) rbd_img_request_complete(img_request); @@ -2225,6 +2235,7 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request, goto out_partial; obj_request->osd_req = osd_req; obj_request->callback = rbd_img_obj_callback; + rbd_img_request_get(img_request); osd_req_op_extent_init(osd_req, 0, opcode, offset, length, 0, 0); @@ -2253,7 +2264,7 @@ out_partial: rbd_obj_request_put(obj_request); out_unwind: for_each_obj_request_safe(img_request, obj_request, next_obj_request) - rbd_obj_request_put(obj_request); + rbd_img_obj_request_del(img_request, obj_request); return -ENOMEM; } @@ -2647,7 +2658,7 @@ static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) */ if (!img_request_write_test(img_request) || !img_request_layered_test(img_request) || - rbd_dev->parent_overlap <= obj_request->img_offset || + !obj_request_overlaps_parent(obj_request) || ((known = obj_request_known_test(obj_request)) && obj_request_exists_test(obj_request))) { @@ -3200,7 +3211,7 @@ static int rbd_obj_read_sync(struct rbd_device *rbd_dev, page_count = (u32) calc_pages_for(offset, length); pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); if (IS_ERR(pages)) - ret = PTR_ERR(pages); + return PTR_ERR(pages); ret = -ENOMEM; obj_request = rbd_obj_request_create(object_name, offset, length, @@ -3887,7 +3898,6 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) */ if (rbd_dev->parent_overlap) { rbd_dev->parent_overlap = 0; - smp_mb(); rbd_dev_parent_put(rbd_dev); pr_info("%s: clone image has been flattened\n", rbd_dev->disk->disk_name); @@ -3931,7 +3941,6 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) * treat it specially. */ rbd_dev->parent_overlap = overlap; - smp_mb(); if (!overlap) { /* A null parent_spec indicates it's the initial probe */ @@ -4747,10 +4756,7 @@ static void rbd_dev_unprobe(struct rbd_device *rbd_dev) { struct rbd_image_header *header; - /* Drop parent reference unless it's already been done (or none) */ - - if (rbd_dev->parent_overlap) - rbd_dev_parent_put(rbd_dev); + rbd_dev_parent_put(rbd_dev); /* Free dynamic fields from the header, then zero it out */ |