rbd: remove snap_name arg from rbd_add_parse_args()

The snapshot name returned by rbd_add_parse_args() just gets saved
in the rbd_dev eventually.  So just do that inside that function and
do away with the snap_name argument, both in rbd_add_parse_args()
and rbd_dev_set_mapping().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 62df67a11321ec37358ef514b2db46acd998c3c9..ae16cf615f02bf396763faa1450f8f06f07213e9 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -665,23 +665,22 @@ static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name)
        return -ENOENT;
 }
 
-static int rbd_dev_set_mapping(struct rbd_device *rbd_dev, char *snap_name)
+static int rbd_dev_set_mapping(struct rbd_device *rbd_dev)
 {
        int ret;
 
-       if (!memcmp(snap_name, RBD_SNAP_HEAD_NAME,
+       if (!memcmp(rbd_dev->snap_name, RBD_SNAP_HEAD_NAME,
                    sizeof (RBD_SNAP_HEAD_NAME))) {
                rbd_dev->snap_id = CEPH_NOSNAP;
                rbd_dev->mapping.size = rbd_dev->header.image_size;
                rbd_dev->mapping.features = rbd_dev->header.features;
                ret = 0;
        } else {
-               ret = snap_by_name(rbd_dev, snap_name);
+               ret = snap_by_name(rbd_dev, rbd_dev->snap_name);
                if (ret < 0)
                        goto done;
                rbd_dev->mapping.read_only = true;
        }
-       rbd_dev->snap_name = snap_name;
        rbd_dev->exists = true;
 done:
        return ret;
@@ -2843,8 +2842,7 @@ static inline char *dup_token(const char **buf, size_t *lenp)
  * Note: rbd_dev is assumed to have been initially zero-filled.
  */
 static struct ceph_options *rbd_add_parse_args(struct rbd_device *rbd_dev,
-                                               const char *buf,
-                                               char **snap_name)
+                                               const char *buf)
 {
        size_t len;
        const char *mon_addrs;
@@ -2893,11 +2891,11 @@ static struct ceph_options *rbd_add_parse_args(struct rbd_device *rbd_dev,
                err_ptr = ERR_PTR(-ENAMETOOLONG);
                goto out_err;
        }
-       *snap_name = kmalloc(len + 1, GFP_KERNEL);
-       if (!*snap_name)
+       rbd_dev->snap_name = kmalloc(len + 1, GFP_KERNEL);
+       if (!rbd_dev->snap_name)
                goto out_mem;
-       memcpy(*snap_name, buf, len);
-       *(*snap_name + len) = '\0';
+       memcpy(rbd_dev->snap_name, buf, len);
+       *(rbd_dev->snap_name + len) = '\0';
 
        /* Initialize all rbd options to the defaults */
 
@@ -3132,7 +3130,6 @@ static ssize_t rbd_add(struct bus_type *bus,
                       size_t count)
 {
        struct rbd_device *rbd_dev = NULL;
-       char *snap_name;
        struct ceph_options *ceph_opts;
        struct ceph_osd_client *osdc;
        int rc = -ENOMEM;
@@ -3151,7 +3148,7 @@ static ssize_t rbd_add(struct bus_type *bus,
        init_rwsem(&rbd_dev->header_rwsem);
 
        /* parse add command */
-       ceph_opts = rbd_add_parse_args(rbd_dev, buf, &snap_name);
+       ceph_opts = rbd_add_parse_args(rbd_dev, buf);
        if (IS_ERR(ceph_opts)) {
                rc = PTR_ERR(ceph_opts);
                goto err_out_mem;
@@ -3178,7 +3175,7 @@ static ssize_t rbd_add(struct bus_type *bus,
        if (rc)
                goto err_out_probe;
 
-       rc = rbd_dev_set_mapping(rbd_dev, snap_name);
+       rc = rbd_dev_set_mapping(rbd_dev);
        if (rc)
                goto err_out_snaps;