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path: root/drivers/block/rbd.c
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Diffstat (limited to 'drivers/block/rbd.c')
-rw-r--r--drivers/block/rbd.c730
1 files changed, 448 insertions, 282 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index a6278e7e61a0..013c7a549fb6 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -41,19 +41,35 @@
#include "rbd_types.h"
-#define DRV_NAME "rbd"
-#define DRV_NAME_LONG "rbd (rados block device)"
+/*
+ * The basic unit of block I/O is a sector. It is interpreted in a
+ * number of contexts in Linux (blk, bio, genhd), but the default is
+ * universally 512 bytes. These symbols are just slightly more
+ * meaningful than the bare numbers they represent.
+ */
+#define SECTOR_SHIFT 9
+#define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
+
+#define RBD_DRV_NAME "rbd"
+#define RBD_DRV_NAME_LONG "rbd (rados block device)"
#define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
-#define RBD_MAX_MD_NAME_LEN (96 + sizeof(RBD_SUFFIX))
+#define RBD_MAX_MD_NAME_LEN (RBD_MAX_OBJ_NAME_LEN + sizeof(RBD_SUFFIX))
#define RBD_MAX_POOL_NAME_LEN 64
#define RBD_MAX_SNAP_NAME_LEN 32
#define RBD_MAX_OPT_LEN 1024
#define RBD_SNAP_HEAD_NAME "-"
+/*
+ * An RBD device name will be "rbd#", where the "rbd" comes from
+ * RBD_DRV_NAME above, and # is a unique integer identifier.
+ * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
+ * enough to hold all possible device names.
+ */
#define DEV_NAME_LEN 32
+#define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
#define RBD_NOTIFY_TIMEOUT_DEFAULT 10
@@ -66,7 +82,6 @@ struct rbd_image_header {
__u8 obj_order;
__u8 crypt_type;
__u8 comp_type;
- struct rw_semaphore snap_rwsem;
struct ceph_snap_context *snapc;
size_t snap_names_len;
u64 snap_seq;
@@ -83,7 +98,7 @@ struct rbd_options {
};
/*
- * an instance of the client. multiple devices may share a client.
+ * an instance of the client. multiple devices may share an rbd client.
*/
struct rbd_client {
struct ceph_client *client;
@@ -92,20 +107,9 @@ struct rbd_client {
struct list_head node;
};
-struct rbd_req_coll;
-
/*
- * a single io request
+ * a request completion status
*/
-struct rbd_request {
- struct request *rq; /* blk layer request */
- struct bio *bio; /* cloned bio */
- struct page **pages; /* list of used pages */
- u64 len;
- int coll_index;
- struct rbd_req_coll *coll;
-};
-
struct rbd_req_status {
int done;
int rc;
@@ -122,6 +126,18 @@ struct rbd_req_coll {
struct rbd_req_status status[0];
};
+/*
+ * a single io request
+ */
+struct rbd_request {
+ struct request *rq; /* blk layer request */
+ struct bio *bio; /* cloned bio */
+ struct page **pages; /* list of used pages */
+ u64 len;
+ int coll_index;
+ struct rbd_req_coll *coll;
+};
+
struct rbd_snap {
struct device dev;
const char *name;
@@ -140,7 +156,6 @@ struct rbd_device {
struct gendisk *disk; /* blkdev's gendisk and rq */
struct request_queue *q;
- struct ceph_client *client;
struct rbd_client *rbd_client;
char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
@@ -157,6 +172,8 @@ struct rbd_device {
struct ceph_osd_event *watch_event;
struct ceph_osd_request *watch_request;
+ /* protects updating the header */
+ struct rw_semaphore header_rwsem;
char snap_name[RBD_MAX_SNAP_NAME_LEN];
u32 cur_snap; /* index+1 of current snapshot within snap context
0 - for the head */
@@ -171,15 +188,13 @@ struct rbd_device {
struct device dev;
};
-static struct bus_type rbd_bus_type = {
- .name = "rbd",
-};
-
-static spinlock_t node_lock; /* protects client get/put */
-
static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
+
static LIST_HEAD(rbd_dev_list); /* devices */
-static LIST_HEAD(rbd_client_list); /* clients */
+static DEFINE_SPINLOCK(rbd_dev_list_lock);
+
+static LIST_HEAD(rbd_client_list); /* clients */
+static DEFINE_SPINLOCK(rbd_client_list_lock);
static int __rbd_init_snaps_header(struct rbd_device *rbd_dev);
static void rbd_dev_release(struct device *dev);
@@ -190,12 +205,32 @@ static ssize_t rbd_snap_add(struct device *dev,
static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev,
struct rbd_snap *snap);
+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 struct rbd_device *dev_to_rbd(struct device *dev)
+static struct bus_attribute rbd_bus_attrs[] = {
+ __ATTR(add, S_IWUSR, NULL, rbd_add),
+ __ATTR(remove, S_IWUSR, NULL, rbd_remove),
+ __ATTR_NULL
+};
+
+static struct bus_type rbd_bus_type = {
+ .name = "rbd",
+ .bus_attrs = rbd_bus_attrs,
+};
+
+static void rbd_root_dev_release(struct device *dev)
{
- return container_of(dev, struct rbd_device, dev);
}
+static struct device rbd_root_dev = {
+ .init_name = "rbd",
+ .release = rbd_root_dev_release,
+};
+
+
static struct device *rbd_get_dev(struct rbd_device *rbd_dev)
{
return get_device(&rbd_dev->dev);
@@ -210,8 +245,7 @@ static int __rbd_update_snaps(struct rbd_device *rbd_dev);
static int rbd_open(struct block_device *bdev, fmode_t mode)
{
- struct gendisk *disk = bdev->bd_disk;
- struct rbd_device *rbd_dev = disk->private_data;
+ struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
rbd_get_dev(rbd_dev);
@@ -256,9 +290,11 @@ static struct rbd_client *rbd_client_create(struct ceph_options *opt,
kref_init(&rbdc->kref);
INIT_LIST_HEAD(&rbdc->node);
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+
rbdc->client = ceph_create_client(opt, rbdc, 0, 0);
if (IS_ERR(rbdc->client))
- goto out_rbdc;
+ goto out_mutex;
opt = NULL; /* Now rbdc->client is responsible for opt */
ret = ceph_open_session(rbdc->client);
@@ -267,16 +303,19 @@ static struct rbd_client *rbd_client_create(struct ceph_options *opt,
rbdc->rbd_opts = rbd_opts;
- spin_lock(&node_lock);
+ spin_lock(&rbd_client_list_lock);
list_add_tail(&rbdc->node, &rbd_client_list);
- spin_unlock(&node_lock);
+ spin_unlock(&rbd_client_list_lock);
+
+ mutex_unlock(&ctl_mutex);
dout("rbd_client_create created %p\n", rbdc);
return rbdc;
out_err:
ceph_destroy_client(rbdc->client);
-out_rbdc:
+out_mutex:
+ mutex_unlock(&ctl_mutex);
kfree(rbdc);
out_opt:
if (opt)
@@ -324,7 +363,7 @@ static int parse_rbd_opts_token(char *c, void *private)
substring_t argstr[MAX_OPT_ARGS];
int token, intval, ret;
- token = match_token((char *)c, rbdopt_tokens, argstr);
+ token = match_token(c, rbdopt_tokens, argstr);
if (token < 0)
return -EINVAL;
@@ -357,58 +396,54 @@ static int parse_rbd_opts_token(char *c, void *private)
* Get a ceph client with specific addr and configuration, if one does
* not exist create it.
*/
-static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr,
- char *options)
+static struct rbd_client *rbd_get_client(const char *mon_addr,
+ size_t mon_addr_len,
+ char *options)
{
struct rbd_client *rbdc;
struct ceph_options *opt;
- int ret;
struct rbd_options *rbd_opts;
rbd_opts = kzalloc(sizeof(*rbd_opts), GFP_KERNEL);
if (!rbd_opts)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
rbd_opts->notify_timeout = RBD_NOTIFY_TIMEOUT_DEFAULT;
- ret = ceph_parse_options(&opt, options, mon_addr,
- mon_addr + strlen(mon_addr), parse_rbd_opts_token, rbd_opts);
- if (ret < 0)
- goto done_err;
+ opt = ceph_parse_options(options, mon_addr,
+ mon_addr + mon_addr_len,
+ parse_rbd_opts_token, rbd_opts);
+ if (IS_ERR(opt)) {
+ kfree(rbd_opts);
+ return ERR_CAST(opt);
+ }
- spin_lock(&node_lock);
+ spin_lock(&rbd_client_list_lock);
rbdc = __rbd_client_find(opt);
if (rbdc) {
+ /* using an existing client */
+ kref_get(&rbdc->kref);
+ spin_unlock(&rbd_client_list_lock);
+
ceph_destroy_options(opt);
kfree(rbd_opts);
- /* using an existing client */
- kref_get(&rbdc->kref);
- rbd_dev->rbd_client = rbdc;
- rbd_dev->client = rbdc->client;
- spin_unlock(&node_lock);
- return 0;
+ return rbdc;
}
- spin_unlock(&node_lock);
+ spin_unlock(&rbd_client_list_lock);
rbdc = rbd_client_create(opt, rbd_opts);
- if (IS_ERR(rbdc)) {
- ret = PTR_ERR(rbdc);
- goto done_err;
- }
- rbd_dev->rbd_client = rbdc;
- rbd_dev->client = rbdc->client;
- return 0;
-done_err:
- kfree(rbd_opts);
- return ret;
+ if (IS_ERR(rbdc))
+ kfree(rbd_opts);
+
+ return rbdc;
}
/*
* Destroy ceph client
*
- * Caller must hold node_lock.
+ * Caller must hold rbd_client_list_lock.
*/
static void rbd_client_release(struct kref *kref)
{
@@ -428,11 +463,10 @@ static void rbd_client_release(struct kref *kref)
*/
static void rbd_put_client(struct rbd_device *rbd_dev)
{
- spin_lock(&node_lock);
+ spin_lock(&rbd_client_list_lock);
kref_put(&rbd_dev->rbd_client->kref, rbd_client_release);
- spin_unlock(&node_lock);
+ spin_unlock(&rbd_client_list_lock);
rbd_dev->rbd_client = NULL;
- rbd_dev->client = NULL;
}
/*
@@ -457,21 +491,19 @@ static int rbd_header_from_disk(struct rbd_image_header *header,
gfp_t gfp_flags)
{
int i;
- u32 snap_count = le32_to_cpu(ondisk->snap_count);
- int ret = -ENOMEM;
+ u32 snap_count;
- if (memcmp(ondisk, RBD_HEADER_TEXT, sizeof(RBD_HEADER_TEXT))) {
+ if (memcmp(ondisk, RBD_HEADER_TEXT, sizeof(RBD_HEADER_TEXT)))
return -ENXIO;
- }
- init_rwsem(&header->snap_rwsem);
- header->snap_names_len = le64_to_cpu(ondisk->snap_names_len);
+ snap_count = le32_to_cpu(ondisk->snap_count);
header->snapc = kmalloc(sizeof(struct ceph_snap_context) +
- snap_count *
- sizeof(struct rbd_image_snap_ondisk),
+ snap_count * sizeof (*ondisk),
gfp_flags);
if (!header->snapc)
return -ENOMEM;
+
+ header->snap_names_len = le64_to_cpu(ondisk->snap_names_len);
if (snap_count) {
header->snap_names = kmalloc(header->snap_names_len,
GFP_KERNEL);
@@ -498,8 +530,7 @@ static int rbd_header_from_disk(struct rbd_image_header *header,
header->snapc->num_snaps = snap_count;
header->total_snaps = snap_count;
- if (snap_count &&
- allocated_snaps == snap_count) {
+ if (snap_count && allocated_snaps == snap_count) {
for (i = 0; i < snap_count; i++) {
header->snapc->snaps[i] =
le64_to_cpu(ondisk->snaps[i].id);
@@ -518,7 +549,7 @@ err_names:
kfree(header->snap_names);
err_snapc:
kfree(header->snapc);
- return ret;
+ return -ENOMEM;
}
static int snap_index(struct rbd_image_header *header, int snap_num)
@@ -542,35 +573,34 @@ static int snap_by_name(struct rbd_image_header *header, const char *snap_name,
int i;
char *p = header->snap_names;
- for (i = 0; i < header->total_snaps; i++, p += strlen(p) + 1) {
- if (strcmp(snap_name, p) == 0)
- break;
- }
- if (i == header->total_snaps)
- return -ENOENT;
- if (seq)
- *seq = header->snapc->snaps[i];
+ for (i = 0; i < header->total_snaps; i++) {
+ if (!strcmp(snap_name, p)) {
- if (size)
- *size = header->snap_sizes[i];
+ /* Found it. Pass back its id and/or size */
- return i;
+ if (seq)
+ *seq = header->snapc->snaps[i];
+ if (size)
+ *size = header->snap_sizes[i];
+ return i;
+ }
+ p += strlen(p) + 1; /* Skip ahead to the next name */
+ }
+ return -ENOENT;
}
-static int rbd_header_set_snap(struct rbd_device *dev,
- const char *snap_name,
- u64 *size)
+static int rbd_header_set_snap(struct rbd_device *dev, u64 *size)
{
struct rbd_image_header *header = &dev->header;
struct ceph_snap_context *snapc = header->snapc;
int ret = -ENOENT;
- down_write(&header->snap_rwsem);
+ BUILD_BUG_ON(sizeof (dev->snap_name) < sizeof (RBD_SNAP_HEAD_NAME));
- if (!snap_name ||
- !*snap_name ||
- strcmp(snap_name, "-") == 0 ||
- strcmp(snap_name, RBD_SNAP_HEAD_NAME) == 0) {
+ down_write(&dev->header_rwsem);
+
+ if (!memcmp(dev->snap_name, RBD_SNAP_HEAD_NAME,
+ sizeof (RBD_SNAP_HEAD_NAME))) {
if (header->total_snaps)
snapc->seq = header->snap_seq;
else
@@ -580,7 +610,7 @@ static int rbd_header_set_snap(struct rbd_device *dev,
if (size)
*size = header->image_size;
} else {
- ret = snap_by_name(header, snap_name, &snapc->seq, size);
+ ret = snap_by_name(header, dev->snap_name, &snapc->seq, size);
if (ret < 0)
goto done;
@@ -590,7 +620,7 @@ static int rbd_header_set_snap(struct rbd_device *dev,
ret = 0;
done:
- up_write(&header->snap_rwsem);
+ up_write(&dev->header_rwsem);
return ret;
}
@@ -717,7 +747,7 @@ static struct bio *bio_chain_clone(struct bio **old, struct bio **next,
/* split the bio. We'll release it either in the next
call, or it will have to be released outside */
- bp = bio_split(old_chain, (len - total) / 512ULL);
+ bp = bio_split(old_chain, (len - total) / SECTOR_SIZE);
if (!bp)
goto err_out;
@@ -857,7 +887,7 @@ static int rbd_do_request(struct request *rq,
struct timespec mtime = CURRENT_TIME;
struct rbd_request *req_data;
struct ceph_osd_request_head *reqhead;
- struct rbd_image_header *header = &dev->header;
+ struct ceph_osd_client *osdc;
req_data = kzalloc(sizeof(*req_data), GFP_NOIO);
if (!req_data) {
@@ -874,15 +904,13 @@ static int rbd_do_request(struct request *rq,
dout("rbd_do_request obj=%s ofs=%lld len=%lld\n", obj, len, ofs);
- down_read(&header->snap_rwsem);
+ down_read(&dev->header_rwsem);
- req = ceph_osdc_alloc_request(&dev->client->osdc, flags,
- snapc,
- ops,
- false,
- GFP_NOIO, pages, bio);
+ osdc = &dev->rbd_client->client->osdc;
+ req = ceph_osdc_alloc_request(osdc, flags, snapc, ops,
+ false, GFP_NOIO, pages, bio);
if (!req) {
- up_read(&header->snap_rwsem);
+ up_read(&dev->header_rwsem);
ret = -ENOMEM;
goto done_pages;
}
@@ -909,27 +937,27 @@ static int rbd_do_request(struct request *rq,
layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
layout->fl_pg_preferred = cpu_to_le32(-1);
layout->fl_pg_pool = cpu_to_le32(dev->poolid);
- ceph_calc_raw_layout(&dev->client->osdc, layout, snapid,
- ofs, &len, &bno, req, ops);
+ ceph_calc_raw_layout(osdc, layout, snapid, ofs, &len, &bno,
+ req, ops);
ceph_osdc_build_request(req, ofs, &len,
ops,
snapc,
&mtime,
req->r_oid, req->r_oid_len);
- up_read(&header->snap_rwsem);
+ up_read(&dev->header_rwsem);
if (linger_req) {
- ceph_osdc_set_request_linger(&dev->client->osdc, req);
+ ceph_osdc_set_request_linger(osdc, req);
*linger_req = req;
}
- ret = ceph_osdc_start_request(&dev->client->osdc, req, false);
+ ret = ceph_osdc_start_request(osdc, req, false);
if (ret < 0)
goto done_err;
if (!rbd_cb) {
- ret = ceph_osdc_wait_request(&dev->client->osdc, req);
+ ret = ceph_osdc_wait_request(osdc, req);
if (ver)
*ver = le64_to_cpu(req->r_reassert_version.version);
dout("reassert_ver=%lld\n",
@@ -1213,8 +1241,8 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
rc = __rbd_update_snaps(dev);
mutex_unlock(&ctl_mutex);
if (rc)
- pr_warning(DRV_NAME "%d got notification but failed to update"
- " snaps: %d\n", dev->major, rc);
+ pr_warning(RBD_DRV_NAME "%d got notification but failed to "
+ " update snaps: %d\n", dev->major, rc);
rbd_req_sync_notify_ack(dev, ver, notify_id, dev->obj_md_name);
}
@@ -1227,7 +1255,7 @@ static int rbd_req_sync_watch(struct rbd_device *dev,
u64 ver)
{
struct ceph_osd_req_op *ops;
- struct ceph_osd_client *osdc = &dev->client->osdc;
+ struct ceph_osd_client *osdc = &dev->rbd_client->client->osdc;
int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0);
if (ret < 0)
@@ -1314,7 +1342,7 @@ static int rbd_req_sync_notify(struct rbd_device *dev,
const char *obj)
{
struct ceph_osd_req_op *ops;
- struct ceph_osd_client *osdc = &dev->client->osdc;
+ struct ceph_osd_client *osdc = &dev->rbd_client->client->osdc;
struct ceph_osd_event *event;
struct rbd_notify_info info;
int payload_len = sizeof(u32) + sizeof(u32);
@@ -1421,9 +1449,7 @@ static void rbd_rq_fn(struct request_queue *q)
struct request *rq;
struct bio_pair *bp = NULL;
- rq = blk_fetch_request(q);
-
- while (1) {
+ while ((rq = blk_fetch_request(q))) {
struct bio *bio;
struct bio *rq_bio, *next_bio = NULL;
bool do_write;
@@ -1441,32 +1467,32 @@ static void rbd_rq_fn(struct request_queue *q)
/* filter out block requests we don't understand */
if ((rq->cmd_type != REQ_TYPE_FS)) {
__blk_end_request_all(rq, 0);
- goto next;
+ continue;
}
/* deduce our operation (read, write) */
do_write = (rq_data_dir(rq) == WRITE);
size = blk_rq_bytes(rq);
- ofs = blk_rq_pos(rq) * 512ULL;
+ ofs = blk_rq_pos(rq) * SECTOR_SIZE;
rq_bio = rq->bio;
if (do_write && rbd_dev->read_only) {
__blk_end_request_all(rq, -EROFS);
- goto next;
+ continue;
}
spin_unlock_irq(q->queue_lock);
dout("%s 0x%x bytes at 0x%llx\n",
do_write ? "write" : "read",
- size, blk_rq_pos(rq) * 512ULL);
+ size, blk_rq_pos(rq) * SECTOR_SIZE);
num_segs = rbd_get_num_segments(&rbd_dev->header, ofs, size);
coll = rbd_alloc_coll(num_segs);
if (!coll) {
spin_lock_irq(q->queue_lock);
__blk_end_request_all(rq, -ENOMEM);
- goto next;
+ continue;
}
do {
@@ -1512,8 +1538,6 @@ next_seg:
if (bp)
bio_pair_release(bp);
spin_lock_irq(q->queue_lock);
-next:
- rq = blk_fetch_request(q);
}
}
@@ -1526,13 +1550,17 @@ static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
struct bio_vec *bvec)
{
struct rbd_device *rbd_dev = q->queuedata;
- unsigned int chunk_sectors = 1 << (rbd_dev->header.obj_order - 9);
- sector_t sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev);
- unsigned int bio_sectors = bmd->bi_size >> 9;
+ unsigned int chunk_sectors;
+ sector_t sector;
+ unsigned int bio_sectors;
int max;
+ chunk_sectors = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
+ sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev);
+ bio_sectors = bmd->bi_size >> SECTOR_SHIFT;
+
max = (chunk_sectors - ((sector & (chunk_sectors - 1))
- + bio_sectors)) << 9;
+ + bio_sectors)) << SECTOR_SHIFT;
if (max < 0)
max = 0; /* bio_add cannot handle a negative return */
if (max <= bvec->bv_len && bio_sectors == 0)
@@ -1565,15 +1593,16 @@ static int rbd_read_header(struct rbd_device *rbd_dev,
ssize_t rc;
struct rbd_image_header_ondisk *dh;
int snap_count = 0;
- u64 snap_names_len = 0;
u64 ver;
+ size_t len;
+ /*
+ * First reads the fixed-size header to determine the number
+ * of snapshots, then re-reads it, along with all snapshot
+ * records as well as their stored names.
+ */
+ len = sizeof (*dh);
while (1) {
- int len = sizeof(*dh) +
- snap_count * sizeof(struct rbd_image_snap_ondisk) +
- snap_names_len;
-
- rc = -ENOMEM;
dh = kmalloc(len, GFP_KERNEL);
if (!dh)
return -ENOMEM;
@@ -1588,21 +1617,22 @@ static int rbd_read_header(struct rbd_device *rbd_dev,
rc = rbd_header_from_disk(header, dh, snap_count, GFP_KERNEL);
if (rc < 0) {
- if (rc == -ENXIO) {
+ if (rc == -ENXIO)
pr_warning("unrecognized header format"
" for image %s", rbd_dev->obj);
- }
goto out_dh;
}
- if (snap_count != header->total_snaps) {
- snap_count = header->total_snaps;
- snap_names_len = header->snap_names_len;
- rbd_header_free(header);
- kfree(dh);
- continue;
- }
- break;
+ if (snap_count == header->total_snaps)
+ break;
+
+ snap_count = header->total_snaps;
+ len = sizeof (*dh) +
+ snap_count * sizeof(struct rbd_image_snap_ondisk) +
+ header->snap_names_len;
+
+ rbd_header_free(header);
+ kfree(dh);
}
header->obj_version = ver;
@@ -1623,13 +1653,14 @@ static int rbd_header_add_snap(struct rbd_device *dev,
int ret;
void *data, *p, *e;
u64 ver;
+ struct ceph_mon_client *monc;
/* we should create a snapshot only if we're pointing at the head */
if (dev->cur_snap)
return -EINVAL;
- ret = ceph_monc_create_snapid(&dev->client->monc, dev->poolid,
- &new_snapid);
+ monc = &dev->rbd_client->client->monc;
+ ret = ceph_monc_create_snapid(monc, dev->poolid, &new_snapid);
dout("created snapid=%lld\n", new_snapid);
if (ret < 0)
return ret;
@@ -1684,9 +1715,9 @@ static int __rbd_update_snaps(struct rbd_device *rbd_dev)
return ret;
/* resized? */
- set_capacity(rbd_dev->disk, h.image_size / 512ULL);
+ set_capacity(rbd_dev->disk, h.image_size / SECTOR_SIZE);
- down_write(&rbd_dev->header.snap_rwsem);
+ down_write(&rbd_dev->header_rwsem);
snap_seq = rbd_dev->header.snapc->seq;
if (rbd_dev->header.total_snaps &&
@@ -1711,7 +1742,7 @@ static int __rbd_update_snaps(struct rbd_device *rbd_dev)
ret = __rbd_init_snaps_header(rbd_dev);
- up_write(&rbd_dev->header.snap_rwsem);
+ up_write(&rbd_dev->header_rwsem);
return ret;
}
@@ -1721,6 +1752,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
struct gendisk *disk;
struct request_queue *q;
int rc;
+ u64 segment_size;
u64 total_size = 0;
/* contact OSD, request size info about the object being mapped */
@@ -1733,7 +1765,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
if (rc)
return rc;
- rc = rbd_header_set_snap(rbd_dev, rbd_dev->snap_name, &total_size);
+ rc = rbd_header_set_snap(rbd_dev, &total_size);
if (rc)
return rc;
@@ -1743,7 +1775,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
if (!disk)
goto out;
- snprintf(disk->disk_name, sizeof(disk->disk_name), DRV_NAME "%d",
+ snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
rbd_dev->id);
disk->major = rbd_dev->major;
disk->first_minor = 0;
@@ -1756,11 +1788,15 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
if (!q)
goto out_disk;
+ /* We use the default size, but let's be explicit about it. */
+ blk_queue_physical_block_size(q, SECTOR_SIZE);
+
/* set io sizes to object size */
- blk_queue_max_hw_sectors(q, rbd_obj_bytes(&rbd_dev->header) / 512ULL);
- blk_queue_max_segment_size(q, rbd_obj_bytes(&rbd_dev->header));
- blk_queue_io_min(q, rbd_obj_bytes(&rbd_dev->header));
- blk_queue_io_opt(q, rbd_obj_bytes(&rbd_dev->header));
+ segment_size = rbd_obj_bytes(&rbd_dev->header);
+ blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
+ blk_queue_max_segment_size(q, segment_size);
+ blk_queue_io_min(q, segment_size);
+ blk_queue_io_opt(q, segment_size);
blk_queue_merge_bvec(q, rbd_merge_bvec);
disk->queue = q;
@@ -1771,7 +1807,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
rbd_dev->q = q;
/* finally, announce the disk to the world */
- set_capacity(disk, total_size / 512ULL);
+ set_capacity(disk, total_size / SECTOR_SIZE);
add_disk(disk);
pr_info("%s: added with size 0x%llx\n",
@@ -1788,10 +1824,15 @@ out:
sysfs
*/
+static struct rbd_device *dev_to_rbd_dev(struct device *dev)
+{
+ return container_of(dev, struct rbd_device, dev);
+}
+
static ssize_t rbd_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
return sprintf(buf, "%llu\n", (unsigned long long)rbd_dev->header.image_size);
}
@@ -1799,7 +1840,7 @@ static ssize_t rbd_size_show(struct device *dev,
static ssize_t rbd_major_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
return sprintf(buf, "%d\n", rbd_dev->major);
}
@@ -1807,15 +1848,16 @@ static ssize_t rbd_major_show(struct device *dev,
static ssize_t rbd_client_id_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
- return sprintf(buf, "client%lld\n", ceph_client_id(rbd_dev->client));
+ return sprintf(buf, "client%lld\n",
+ ceph_client_id(rbd_dev->rbd_client->client));
}
static ssize_t rbd_pool_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
return sprintf(buf, "%s\n", rbd_dev->pool_name);
}
@@ -1823,7 +1865,7 @@ static ssize_t rbd_pool_show(struct device *dev,
static ssize_t rbd_name_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
return sprintf(buf, "%s\n", rbd_dev->obj);
}
@@ -1832,7 +1874,7 @@ static ssize_t rbd_snap_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
return sprintf(buf, "%s\n", rbd_dev->snap_name);
}
@@ -1842,7 +1884,7 @@ static ssize_t rbd_image_refresh(struct device *dev,
const char *buf,
size_t size)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
int rc;
int ret = size;
@@ -1907,7 +1949,7 @@ static ssize_t rbd_snap_size_show(struct device *dev,
{
struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
- return sprintf(buf, "%lld\n", (long long)snap->size);
+ return sprintf(buf, "%zd\n", snap->size);
}
static ssize_t rbd_snap_id_show(struct device *dev,
@@ -1916,7 +1958,7 @@ static ssize_t rbd_snap_id_show(struct device *dev,
{
struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
- return sprintf(buf, "%lld\n", (long long)snap->id);
+ return sprintf(buf, "%llu\n", (unsigned long long) snap->id);
}
static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
@@ -2088,19 +2130,9 @@ static int __rbd_init_snaps_header(struct rbd_device *rbd_dev)
return 0;
}
-
-static void rbd_root_dev_release(struct device *dev)
-{
-}
-
-static struct device rbd_root_dev = {
- .init_name = "rbd",
- .release = rbd_root_dev_release,
-};
-
static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
{
- int ret = -ENOMEM;
+ int ret;
struct device *dev;
struct rbd_snap *snap;
@@ -2114,7 +2146,7 @@ static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
dev_set_name(dev, "%d", rbd_dev->id);
ret = device_register(dev);
if (ret < 0)
- goto done_free;
+ goto out;
list_for_each_entry(snap, &rbd_dev->snaps, node) {
ret = rbd_register_snap_dev(rbd_dev, snap,
@@ -2122,10 +2154,7 @@ static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
if (ret < 0)
break;
}
-
- mutex_unlock(&ctl_mutex);
- return 0;
-done_free:
+out:
mutex_unlock(&ctl_mutex);
return ret;
}
@@ -2154,104 +2183,250 @@ static int rbd_init_watch_dev(struct rbd_device *rbd_dev)
return ret;
}
+static atomic64_t rbd_id_max = ATOMIC64_INIT(0);
+
+/*
+ * Get a unique rbd identifier for the given new rbd_dev, and add
+ * the rbd_dev to the global list. The minimum rbd id is 1.
+ */
+static void rbd_id_get(struct rbd_device *rbd_dev)
+{
+ rbd_dev->id = atomic64_inc_return(&rbd_id_max);
+
+ spin_lock(&rbd_dev_list_lock);
+ list_add_tail(&rbd_dev->node, &rbd_dev_list);
+ spin_unlock(&rbd_dev_list_lock);
+}
+
+/*
+ * Remove an rbd_dev from the global list, and record that its
+ * identifier is no longer in use.
+ */
+static void rbd_id_put(struct rbd_device *rbd_dev)
+{
+ struct list_head *tmp;
+ int rbd_id = rbd_dev->id;
+ int max_id;
+
+ BUG_ON(rbd_id < 1);
+
+ spin_lock(&rbd_dev_list_lock);
+ list_del_init(&rbd_dev->node);
+
+ /*
+ * If the id being "put" is not the current maximum, there
+ * is nothing special we need to do.
+ */
+ if (rbd_id != atomic64_read(&rbd_id_max)) {
+ spin_unlock(&rbd_dev_list_lock);
+ return;
+ }
+
+ /*
+ * We need to update the current maximum id. Search the
+ * list to find out what it is. We're more likely to find
+ * the maximum at the end, so search the list backward.
+ */
+ max_id = 0;
+ list_for_each_prev(tmp, &rbd_dev_list) {
+ struct rbd_device *rbd_dev;
+
+ rbd_dev = list_entry(tmp, struct rbd_device, node);
+ if (rbd_id > max_id)
+ max_id = rbd_id;
+ }
+ spin_unlock(&rbd_dev_list_lock);
+
+ /*
+ * The max id could have been updated by rbd_id_get(), in
+ * which case it now accurately reflects the new maximum.
+ * Be careful not to overwrite the maximum value in that
+ * case.
+ */
+ atomic64_cmpxchg(&rbd_id_max, rbd_id, max_id);
+}
+
+/*
+ * Skips over white space at *buf, and updates *buf to point to the
+ * first found non-space character (if any). Returns the length of
+ * the token (string of non-white space characters) found. Note
+ * that *buf must be terminated with '\0'.
+ */
+static inline size_t next_token(const char **buf)
+{
+ /*
+ * These are the characters that produce nonzero for
+ * isspace() in the "C" and "POSIX" locales.
+ */
+ const char *spaces = " \f\n\r\t\v";
+
+ *buf += strspn(*buf, spaces); /* Find start of token */
+
+ return strcspn(*buf, spaces); /* Return token length */
+}
+
+/*
+ * Finds the next token in *buf, and if the provided token buffer is
+ * big enough, copies the found token into it. The result, if
+ * copied, is guaranteed to be terminated with '\0'. Note that *buf
+ * must be terminated with '\0' on entry.
+ *
+ * Returns the length of the token found (not including the '\0').
+ * Return value will be 0 if no token is found, and it will be >=
+ * token_size if the token would not fit.
+ *
+ * The *buf pointer will be updated to point beyond the end of the
+ * found token. Note that this occurs even if the token buffer is
+ * too small to hold it.
+ */
+static inline size_t copy_token(const char **buf,
+ char *token,
+ size_t token_size)
+{
+ size_t len;
+
+ len = next_token(buf);
+ if (len < token_size) {
+ memcpy(token, *buf, len);
+ *(token + len) = '\0';
+ }
+ *buf += len;
+
+ return len;
+}
+
+/*
+ * This fills in the pool_name, obj, obj_len, snap_name, obj_len,
+ * rbd_dev, rbd_md_name, and name fields of the given rbd_dev, based
+ * on the list of monitor addresses and other options provided via
+ * /sys/bus/rbd/add.
+ */
+static int rbd_add_parse_args(struct rbd_device *rbd_dev,
+ const char *buf,
+ const char **mon_addrs,
+ size_t *mon_addrs_size,
+ char *options,
+ size_t options_size)
+{
+ size_t len;
+
+ /* The first four tokens are required */
+
+ len = next_token(&buf);
+ if (!len)
+ return -EINVAL;
+ *mon_addrs_size = len + 1;
+ *mon_addrs = buf;
+
+ buf += len;
+
+ len = copy_token(&buf, options, options_size);
+ if (!len || len >= options_size)
+ return -EINVAL;
+
+ len = copy_token(&buf, rbd_dev->pool_name, sizeof (rbd_dev->pool_name));
+ if (!len || len >= sizeof (rbd_dev->pool_name))
+ return -EINVAL;
+
+ len = copy_token(&buf, rbd_dev->obj, sizeof (rbd_dev->obj));
+ if (!len || len >= sizeof (rbd_dev->obj))
+ return -EINVAL;
+
+ /* We have the object length in hand, save it. */
+
+ rbd_dev->obj_len = len;
+
+ BUILD_BUG_ON(RBD_MAX_MD_NAME_LEN
+ < RBD_MAX_OBJ_NAME_LEN + sizeof (RBD_SUFFIX));
+ sprintf(rbd_dev->obj_md_name, "%s%s", rbd_dev->obj, RBD_SUFFIX);
+
+ /*
+ * The snapshot name is optional, but it's an error if it's
+ * too long. If no snapshot is supplied, fill in the default.
+ */
+ len = copy_token(&buf, rbd_dev->snap_name, sizeof (rbd_dev->snap_name));
+ if (!len)
+ memcpy(rbd_dev->snap_name, RBD_SNAP_HEAD_NAME,
+ sizeof (RBD_SNAP_HEAD_NAME));
+ else if (len >= sizeof (rbd_dev->snap_name))
+ return -EINVAL;
+
+ return 0;
+}
+
static ssize_t rbd_add(struct bus_type *bus,
const char *buf,
size_t count)
{
- struct ceph_osd_client *osdc;
struct rbd_device *rbd_dev;
- ssize_t rc = -ENOMEM;
- int irc, new_id = 0;
- struct list_head *tmp;
- char *mon_dev_name;
- char *options;
+ const char *mon_addrs = NULL;
+ size_t mon_addrs_size = 0;
+ char *options = NULL;
+ struct ceph_osd_client *osdc;
+ int rc = -ENOMEM;
if (!try_module_get(THIS_MODULE))
return -ENODEV;
- mon_dev_name = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
- if (!mon_dev_name)
- goto err_out_mod;
-
- options = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
- if (!options)
- goto err_mon_dev;
-
- /* new rbd_device object */
rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
if (!rbd_dev)
- goto err_out_opt;
+ goto err_nomem;
+ options = kmalloc(count, GFP_KERNEL);
+ if (!options)
+ goto err_nomem;
/* static rbd_device initialization */
spin_lock_init(&rbd_dev->lock);
INIT_LIST_HEAD(&rbd_dev->node);
INIT_LIST_HEAD(&rbd_dev->snaps);
+ init_rwsem(&rbd_dev->header_rwsem);
- init_rwsem(&rbd_dev->header.snap_rwsem);
+ init_rwsem(&rbd_dev->header_rwsem);
/* generate unique id: find highest unique id, add one */
- mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
-
- list_for_each(tmp, &rbd_dev_list) {
- struct rbd_device *rbd_dev;
+ rbd_id_get(rbd_dev);
- rbd_dev = list_entry(tmp, struct rbd_device, node);
- if (rbd_dev->id >= new_id)
- new_id = rbd_dev->id + 1;
- }
-
- rbd_dev->id = new_id;
-
- /* add to global list */
- list_add_tail(&rbd_dev->node, &rbd_dev_list);
+ /* Fill in the device name, now that we have its id. */
+ BUILD_BUG_ON(DEV_NAME_LEN
+ < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
+ sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->id);
/* parse add command */
- if (sscanf(buf, "%" __stringify(RBD_MAX_OPT_LEN) "s "
- "%" __stringify(RBD_MAX_OPT_LEN) "s "
- "%" __stringify(RBD_MAX_POOL_NAME_LEN) "s "
- "%" __stringify(RBD_MAX_OBJ_NAME_LEN) "s"
- "%" __stringify(RBD_MAX_SNAP_NAME_LEN) "s",
- mon_dev_name, options, rbd_dev->pool_name,
- rbd_dev->obj, rbd_dev->snap_name) < 4) {
- rc = -EINVAL;
- goto err_out_slot;
- }
-
- if (rbd_dev->snap_name[0] == 0)
- rbd_dev->snap_name[0] = '-';
-
- rbd_dev->obj_len = strlen(rbd_dev->obj);
- snprintf(rbd_dev->obj_md_name, sizeof(rbd_dev->obj_md_name), "%s%s",
- rbd_dev->obj, RBD_SUFFIX);
-
- /* initialize rest of new object */
- snprintf(rbd_dev->name, DEV_NAME_LEN, DRV_NAME "%d", rbd_dev->id);
- rc = rbd_get_client(rbd_dev, mon_dev_name, options);
- if (rc < 0)
- goto err_out_slot;
+ rc = rbd_add_parse_args(rbd_dev, buf, &mon_addrs, &mon_addrs_size,
+ options, count);
+ if (rc)
+ goto err_put_id;
- mutex_unlock(&ctl_mutex);
+ rbd_dev->rbd_client = rbd_get_client(mon_addrs, mon_addrs_size - 1,
+ options);
+ if (IS_ERR(rbd_dev->rbd_client)) {
+ rc = PTR_ERR(rbd_dev->rbd_client);
+ goto err_put_id;
+ }
/* pick the pool */
- osdc = &rbd_dev->client->osdc;
+ osdc = &rbd_dev->rbd_client->client->osdc;
rc = ceph_pg_poolid_by_name(osdc->osdmap, rbd_dev->pool_name);
if (rc < 0)
goto err_out_client;
rbd_dev->poolid = rc;
/* register our block device */
- irc = register_blkdev(0, rbd_dev->name);
- if (irc < 0) {
- rc = irc;
+ rc = register_blkdev(0, rbd_dev->name);
+ if (rc < 0)
goto err_out_client;
- }
- rbd_dev->major = irc;
+ rbd_dev->major = rc;
rc = rbd_bus_add_dev(rbd_dev);
if (rc)
goto err_out_blkdev;
- /* set up and announce blkdev mapping */
+ /*
+ * At this point cleanup in the event of an error is the job
+ * of the sysfs code (initiated by rbd_bus_del_dev()).
+ *
+ * Set up and announce blkdev mapping.
+ */
rc = rbd_init_disk(rbd_dev);
if (rc)
goto err_out_bus;
@@ -2263,35 +2438,26 @@ static ssize_t rbd_add(struct bus_type *bus,
return count;
err_out_bus:
- mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
- list_del_init(&rbd_dev->node);
- mutex_unlock(&ctl_mutex);
-
/* this will also clean up rest of rbd_dev stuff */
rbd_bus_del_dev(rbd_dev);
kfree(options);
- kfree(mon_dev_name);
return rc;
err_out_blkdev:
unregister_blkdev(rbd_dev->major, rbd_dev->name);
err_out_client:
rbd_put_client(rbd_dev);
- mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
-err_out_slot:
- list_del_init(&rbd_dev->node);
- mutex_unlock(&ctl_mutex);
-
- kfree(rbd_dev);
-err_out_opt:
+err_put_id:
+ rbd_id_put(rbd_dev);
+err_nomem:
kfree(options);
-err_mon_dev:
- kfree(mon_dev_name);
-err_out_mod:
+ kfree(rbd_dev);
+
dout("Error adding device %s\n", buf);
module_put(THIS_MODULE);
- return rc;
+
+ return (ssize_t) rc;
}
static struct rbd_device *__rbd_get_dev(unsigned long id)
@@ -2299,22 +2465,28 @@ static struct rbd_device *__rbd_get_dev(unsigned long id)
struct list_head *tmp;
struct rbd_device *rbd_dev;
+ spin_lock(&rbd_dev_list_lock);
list_for_each(tmp, &rbd_dev_list) {
rbd_dev = list_entry(tmp, struct rbd_device, node);
- if (rbd_dev->id == id)
+ if (rbd_dev->id == id) {
+ spin_unlock(&rbd_dev_list_lock);
return rbd_dev;
+ }
}
+ spin_unlock(&rbd_dev_list_lock);
return NULL;
}
static void rbd_dev_release(struct device *dev)
{
- struct rbd_device *rbd_dev =
- container_of(dev, struct rbd_device, dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
- if (rbd_dev->watch_request)
- ceph_osdc_unregister_linger_request(&rbd_dev->client->osdc,
+ if (rbd_dev->watch_request) {
+ struct ceph_client *client = rbd_dev->rbd_client->client;
+
+ ceph_osdc_unregister_linger_request(&client->osdc,
rbd_dev->watch_request);
+ }
if (rbd_dev->watch_event)
rbd_req_sync_unwatch(rbd_dev, rbd_dev->obj_md_name);
@@ -2323,6 +2495,9 @@ static void rbd_dev_release(struct device *dev)
/* clean up and free blkdev */
rbd_free_disk(rbd_dev);
unregister_blkdev(rbd_dev->major, rbd_dev->name);
+
+ /* done with the id, and with the rbd_dev */
+ rbd_id_put(rbd_dev);
kfree(rbd_dev);
/* release module ref */
@@ -2355,8 +2530,6 @@ static ssize_t rbd_remove(struct bus_type *bus,
goto done;
}
- list_del_init(&rbd_dev->node);
-
__rbd_remove_all_snaps(rbd_dev);
rbd_bus_del_dev(rbd_dev);
@@ -2370,7 +2543,7 @@ static ssize_t rbd_snap_add(struct device *dev,
const char *buf,
size_t count)
{
- struct rbd_device *rbd_dev = dev_to_rbd(dev);
+ struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
int ret;
char *name = kmalloc(count + 1, GFP_KERNEL);
if (!name)
@@ -2406,12 +2579,6 @@ err_unlock:
return ret;
}
-static struct bus_attribute rbd_bus_attrs[] = {
- __ATTR(add, S_IWUSR, NULL, rbd_add),
- __ATTR(remove, S_IWUSR, NULL, rbd_remove),
- __ATTR_NULL
-};
-
/*
* create control files in sysfs
* /sys/bus/rbd/...
@@ -2420,21 +2587,21 @@ static int rbd_sysfs_init(void)
{
int ret;
- rbd_bus_type.bus_attrs = rbd_bus_attrs;
-
- ret = bus_register(&rbd_bus_type);
- if (ret < 0)
+ ret = device_register(&rbd_root_dev);
+ if (ret < 0)
return ret;
- ret = device_register(&rbd_root_dev);
+ ret = bus_register(&rbd_bus_type);
+ if (ret < 0)
+ device_unregister(&rbd_root_dev);
return ret;
}
static void rbd_sysfs_cleanup(void)
{
- device_unregister(&rbd_root_dev);
bus_unregister(&rbd_bus_type);
+ device_unregister(&rbd_root_dev);
}
int __init rbd_init(void)
@@ -2444,8 +2611,7 @@ int __init rbd_init(void)
rc = rbd_sysfs_init();
if (rc)
return rc;
- spin_lock_init(&node_lock);
- pr_info("loaded " DRV_NAME_LONG "\n");
+ pr_info("loaded " RBD_DRV_NAME_LONG "\n");
return 0;
}