X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fblock%2Frbd.c;h=235708c7c46eee709acb110acb95a28d85ebc946;hb=63f4f7e8df6c504f39c6493799b54775916030d6;hp=128e7df5b807222ba2d6f50148cb164919a308f7;hpb=400c5bd5a5b1faf3089322ace58b974446a8ddc3;p=firefly-linux-kernel-4.4.55.git diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 128e7df5b807..235708c7c46e 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -418,8 +418,6 @@ MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (d static int rbd_img_request_submit(struct rbd_img_request *img_request); -static void rbd_dev_device_release(struct device *dev); - 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, @@ -3991,14 +3989,12 @@ static const struct attribute_group *rbd_attr_groups[] = { NULL }; -static void rbd_sysfs_dev_release(struct device *dev) -{ -} +static void rbd_dev_release(struct device *dev); static struct device_type rbd_device_type = { .name = "rbd", .groups = rbd_attr_groups, - .release = rbd_sysfs_dev_release, + .release = rbd_dev_release, }; static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec) @@ -4041,6 +4037,25 @@ static void rbd_spec_free(struct kref *kref) kfree(spec); } +static void rbd_dev_release(struct device *dev) +{ + struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); + bool need_put = !!rbd_dev->opts; + + rbd_put_client(rbd_dev->rbd_client); + rbd_spec_put(rbd_dev->spec); + kfree(rbd_dev->opts); + kfree(rbd_dev); + + /* + * This is racy, but way better than putting module outside of + * the release callback. The race window is pretty small, so + * doing something similar to dm (dm-builtin.c) is overkill. + */ + if (need_put) + module_put(THIS_MODULE); +} + static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, struct rbd_spec *spec, struct rbd_options *opts) @@ -4057,6 +4072,11 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, INIT_LIST_HEAD(&rbd_dev->node); init_rwsem(&rbd_dev->header_rwsem); + rbd_dev->dev.bus = &rbd_bus_type; + rbd_dev->dev.type = &rbd_device_type; + rbd_dev->dev.parent = &rbd_root_dev; + device_initialize(&rbd_dev->dev); + rbd_dev->rbd_client = rbdc; rbd_dev->spec = spec; rbd_dev->opts = opts; @@ -4068,15 +4088,21 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id); + /* + * If this is a mapping rbd_dev (as opposed to a parent one), + * pin our module. We have a ref from do_rbd_add(), so use + * __module_get(). + */ + if (rbd_dev->opts) + __module_get(THIS_MODULE); + return rbd_dev; } static void rbd_dev_destroy(struct rbd_device *rbd_dev) { - rbd_put_client(rbd_dev->rbd_client); - rbd_spec_put(rbd_dev->spec); - kfree(rbd_dev->opts); - kfree(rbd_dev); + if (rbd_dev) + put_device(&rbd_dev->dev); } /* @@ -4702,27 +4728,6 @@ static int rbd_dev_header_info(struct rbd_device *rbd_dev) return rbd_dev_v2_header_info(rbd_dev); } -static int rbd_bus_add_dev(struct rbd_device *rbd_dev) -{ - struct device *dev; - int ret; - - dev = &rbd_dev->dev; - dev->bus = &rbd_bus_type; - dev->type = &rbd_device_type; - dev->parent = &rbd_root_dev; - dev->release = rbd_dev_device_release; - dev_set_name(dev, "%d", rbd_dev->dev_id); - ret = device_register(dev); - - return ret; -} - -static void rbd_bus_del_dev(struct rbd_device *rbd_dev) -{ - device_unregister(&rbd_dev->dev); -} - /* * Get a unique rbd identifier for the given new rbd_dev, and add * the rbd_dev to the global list. @@ -5225,7 +5230,8 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev) set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE); set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only); - ret = rbd_bus_add_dev(rbd_dev); + dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id); + ret = device_add(&rbd_dev->dev); if (ret) goto err_out_mapping; @@ -5248,8 +5254,6 @@ err_out_blkdev: unregister_blkdev(rbd_dev->major, rbd_dev->name); err_out_id: rbd_dev_id_put(rbd_dev); - rbd_dev_mapping_clear(rbd_dev); - return ret; } @@ -5397,7 +5401,7 @@ static ssize_t do_rbd_add(struct bus_type *bus, struct rbd_spec *spec = NULL; struct rbd_client *rbdc; bool read_only; - int rc = -ENOMEM; + int rc; if (!try_module_get(THIS_MODULE)) return -ENODEV; @@ -5405,7 +5409,7 @@ static ssize_t do_rbd_add(struct bus_type *bus, /* parse add command */ rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec); if (rc < 0) - goto err_out_module; + goto out; rbdc = rbd_get_client(ceph_opts); if (IS_ERR(rbdc)) { @@ -5432,8 +5436,10 @@ static ssize_t do_rbd_add(struct bus_type *bus, } rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts); - if (!rbd_dev) + if (!rbd_dev) { + rc = -ENOMEM; goto err_out_client; + } rbdc = NULL; /* rbd_dev now owns this */ spec = NULL; /* rbd_dev now owns this */ rbd_opts = NULL; /* rbd_dev now owns this */ @@ -5458,10 +5464,13 @@ static ssize_t do_rbd_add(struct bus_type *bus, */ rbd_dev_header_unwatch_sync(rbd_dev); rbd_dev_image_release(rbd_dev); - goto err_out_module; + goto out; } - return count; + rc = count; +out: + module_put(THIS_MODULE); + return rc; err_out_rbd_dev: rbd_dev_destroy(rbd_dev); @@ -5470,12 +5479,7 @@ err_out_client: err_out_args: rbd_spec_put(spec); kfree(rbd_opts); -err_out_module: - module_put(THIS_MODULE); - - dout("Error adding device %s\n", buf); - - return (ssize_t)rc; + goto out; } static ssize_t rbd_add(struct bus_type *bus, @@ -5495,17 +5499,15 @@ static ssize_t rbd_add_single_major(struct bus_type *bus, return do_rbd_add(bus, buf, count); } -static void rbd_dev_device_release(struct device *dev) +static void rbd_dev_device_release(struct rbd_device *rbd_dev) { - struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); - rbd_free_disk(rbd_dev); clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); + device_del(&rbd_dev->dev); rbd_dev_mapping_clear(rbd_dev); if (!single_major) unregister_blkdev(rbd_dev->major, rbd_dev->name); rbd_dev_id_put(rbd_dev); - rbd_dev_mapping_clear(rbd_dev); } static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) @@ -5590,9 +5592,8 @@ static ssize_t do_rbd_remove(struct bus_type *bus, * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting * in a potential use after free of rbd_dev->disk or rbd_dev. */ - rbd_bus_del_dev(rbd_dev); + rbd_dev_device_release(rbd_dev); rbd_dev_image_release(rbd_dev); - module_put(THIS_MODULE); return count; } @@ -5663,10 +5664,8 @@ static int rbd_slab_init(void) if (rbd_segment_name_cache) return 0; out_err: - if (rbd_obj_request_cache) { - kmem_cache_destroy(rbd_obj_request_cache); - rbd_obj_request_cache = NULL; - } + kmem_cache_destroy(rbd_obj_request_cache); + rbd_obj_request_cache = NULL; kmem_cache_destroy(rbd_img_request_cache); rbd_img_request_cache = NULL;