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-rw-r--r--Documentation/ABI/testing/sysfs-bus-rbd22
-rw-r--r--drivers/block/rbd.c132
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();
}
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