diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-rbd | 22 | ||||
| -rw-r--r-- | drivers/block/rbd.c | 132 |
2 files changed, 134 insertions, 20 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-rbd b/Documentation/ABI/testing/sysfs-bus-rbd index 17b119c692da..501adc2a9ec7 100644 --- a/Documentation/ABI/testing/sysfs-bus-rbd +++ b/Documentation/ABI/testing/sysfs-bus-rbd @@ -18,6 +18,28 @@ Removal of a device: $ echo <dev-id> > /sys/bus/rbd/remove +What: /sys/bus/rbd/add_single_major +Date: December 2013 +KernelVersion: 3.14 +Contact: Sage Weil <sage@inktank.com> +Description: Available only if rbd module is inserted with single_major + parameter set to true. + Usage is the same as for /sys/bus/rbd/add. If present, + should be used instead of the latter: any attempts to use + /sys/bus/rbd/add if /sys/bus/rbd/add_single_major is + available will fail for backwards compatibility reasons. + +What: /sys/bus/rbd/remove_single_major +Date: December 2013 +KernelVersion: 3.14 +Contact: Sage Weil <sage@inktank.com> +Description: Available only if rbd module is inserted with single_major + parameter set to true. + Usage is the same as for /sys/bus/rbd/remove. If present, + should be used instead of the latter: any attempts to use + /sys/bus/rbd/remove if /sys/bus/rbd/remove_single_major is + available will fail for backwards compatibility reasons. + Entries under /sys/bus/rbd/devices/<dev-id>/ -------------------------------------------- diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 3fa18b0c5e4d..e5ddcb58e9a2 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -91,7 +91,7 @@ static int atomic_dec_return_safe(atomic_t *v) #define RBD_DRV_NAME "rbd" -#define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */ +#define RBD_PART_SHIFT 8 #define RBD_SNAP_DEV_NAME_PREFIX "snap_" #define RBD_MAX_SNAP_NAME_LEN \ @@ -387,8 +387,17 @@ static struct kmem_cache *rbd_img_request_cache; static struct kmem_cache *rbd_obj_request_cache; static struct kmem_cache *rbd_segment_name_cache; +static int rbd_major; static DEFINE_IDA(rbd_dev_id_ida); +/* + * Default to false for now, as single-major requires >= 0.75 version of + * userspace rbd utility. + */ +static bool single_major = false; +module_param(single_major, bool, S_IRUGO); +MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)"); + static int rbd_img_request_submit(struct rbd_img_request *img_request); static void rbd_dev_device_release(struct device *dev); @@ -397,21 +406,44 @@ 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 ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf, + size_t count); +static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf, + size_t count); static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping); static void rbd_spec_put(struct rbd_spec *spec); +static int rbd_dev_id_to_minor(int dev_id) +{ + return dev_id << RBD_PART_SHIFT; +} + +static int minor_to_rbd_dev_id(int minor) +{ + return minor >> RBD_PART_SHIFT; +} + static BUS_ATTR(add, S_IWUSR, NULL, rbd_add); static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove); +static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major); +static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major); static struct attribute *rbd_bus_attrs[] = { &bus_attr_add.attr, &bus_attr_remove.attr, + &bus_attr_add_single_major.attr, + &bus_attr_remove_single_major.attr, NULL, }; static umode_t rbd_bus_is_visible(struct kobject *kobj, struct attribute *attr, int index) { + if (!single_major && + (attr == &bus_attr_add_single_major.attr || + attr == &bus_attr_remove_single_major.attr)) + return 0; + return attr->mode; } @@ -3402,7 +3434,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev) u64 segment_size; /* create gendisk info */ - disk = alloc_disk(RBD_MINORS_PER_MAJOR); + disk = alloc_disk(1 << RBD_PART_SHIFT); if (!disk) return -ENOMEM; @@ -4403,7 +4435,9 @@ static int rbd_dev_id_get(struct rbd_device *rbd_dev) { int new_dev_id; - new_dev_id = ida_simple_get(&rbd_dev_id_ida, 0, 0, GFP_KERNEL); + new_dev_id = ida_simple_get(&rbd_dev_id_ida, + 0, minor_to_rbd_dev_id(1 << MINORBITS), + GFP_KERNEL); if (new_dev_id < 0) return new_dev_id; @@ -4863,13 +4897,19 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev) < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH); sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id); - /* Get our block major device number. */ + /* Record our major and minor device numbers. */ - ret = register_blkdev(0, rbd_dev->name); - if (ret < 0) - goto err_out_id; - rbd_dev->major = ret; - rbd_dev->minor = 0; + if (!single_major) { + ret = register_blkdev(0, rbd_dev->name); + if (ret < 0) + goto err_out_id; + + rbd_dev->major = ret; + rbd_dev->minor = 0; + } else { + rbd_dev->major = rbd_major; + rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id); + } /* Set up the blkdev mapping. */ @@ -4901,7 +4941,8 @@ err_out_mapping: err_out_disk: rbd_free_disk(rbd_dev); err_out_blkdev: - unregister_blkdev(rbd_dev->major, rbd_dev->name); + if (!single_major) + unregister_blkdev(rbd_dev->major, rbd_dev->name); err_out_id: rbd_dev_id_put(rbd_dev); rbd_dev_mapping_clear(rbd_dev); @@ -5022,9 +5063,9 @@ err_out_format: return ret; } -static ssize_t rbd_add(struct bus_type *bus, - const char *buf, - size_t count) +static ssize_t do_rbd_add(struct bus_type *bus, + const char *buf, + size_t count) { struct rbd_device *rbd_dev = NULL; struct ceph_options *ceph_opts = NULL; @@ -5106,6 +5147,23 @@ err_out_module: return (ssize_t)rc; } +static ssize_t rbd_add(struct bus_type *bus, + const char *buf, + size_t count) +{ + if (single_major) + return -EINVAL; + + return do_rbd_add(bus, buf, count); +} + +static ssize_t rbd_add_single_major(struct bus_type *bus, + const char *buf, + size_t count) +{ + return do_rbd_add(bus, buf, count); +} + static void rbd_dev_device_release(struct device *dev) { struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); @@ -5113,8 +5171,8 @@ static void rbd_dev_device_release(struct device *dev) rbd_free_disk(rbd_dev); clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); rbd_dev_mapping_clear(rbd_dev); - unregister_blkdev(rbd_dev->major, rbd_dev->name); - rbd_dev->major = 0; + if (!single_major) + unregister_blkdev(rbd_dev->major, rbd_dev->name); rbd_dev_id_put(rbd_dev); rbd_dev_mapping_clear(rbd_dev); } @@ -5145,9 +5203,9 @@ static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) } } -static ssize_t rbd_remove(struct bus_type *bus, - const char *buf, - size_t count) +static ssize_t do_rbd_remove(struct bus_type *bus, + const char *buf, + size_t count) { struct rbd_device *rbd_dev = NULL; struct list_head *tmp; @@ -5210,6 +5268,23 @@ static ssize_t rbd_remove(struct bus_type *bus, return count; } +static ssize_t rbd_remove(struct bus_type *bus, + const char *buf, + size_t count) +{ + if (single_major) + return -EINVAL; + + return do_rbd_remove(bus, buf, count); +} + +static ssize_t rbd_remove_single_major(struct bus_type *bus, + const char *buf, + size_t count) +{ + return do_rbd_remove(bus, buf, count); +} + /* * create control files in sysfs * /sys/bus/rbd/... @@ -5298,13 +5373,28 @@ static int __init rbd_init(void) if (rc) return rc; + if (single_major) { + rbd_major = register_blkdev(0, RBD_DRV_NAME); + if (rbd_major < 0) { + rc = rbd_major; + goto err_out_slab; + } + } + rc = rbd_sysfs_init(); if (rc) - goto err_out_slab; + goto err_out_blkdev; + + if (single_major) + pr_info("loaded (major %d)\n", rbd_major); + else + pr_info("loaded\n"); - pr_info("loaded\n"); return 0; +err_out_blkdev: + if (single_major) + unregister_blkdev(rbd_major, RBD_DRV_NAME); err_out_slab: rbd_slab_exit(); return rc; @@ -5313,6 +5403,8 @@ err_out_slab: static void __exit rbd_exit(void) { rbd_sysfs_cleanup(); + if (single_major) + unregister_blkdev(rbd_major, RBD_DRV_NAME); rbd_slab_exit(); } |