From 3feeb8946739d980fb0922bf68363552a493a49c Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Fri, 31 Aug 2012 17:29:52 -0500 Subject: [PATCH] rbd: return snap name from rbd_add_parse_args() This is the first of two patches aimed at isolating the code that sets the mapping information into a single spot. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 72 +++++++++++++++++++++++---------------------- 1 file changed, 37 insertions(+), 35 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 4377a8302fc3..1a64ba294a76 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -2477,28 +2477,31 @@ static inline char *dup_token(const char **buf, size_t *lenp) } /* - * This fills in the pool_name, image_name, image_name_len, snap_name, - * 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. + * This fills in the pool_name, image_name, image_name_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. Returns a pointer to a dynamically-allocated + * copy of the snapshot name to map if successful, or a + * pointer-coded error otherwise. * * Note: rbd_dev is assumed to have been initially zero-filled. */ -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) +static char *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; - int ret; + char *err_ptr = ERR_PTR(-EINVAL); + char *snap_name; /* The first four tokens are required */ len = next_token(&buf); if (!len) - return -EINVAL; + return err_ptr; *mon_addrs_size = len + 1; *mon_addrs = buf; @@ -2506,9 +2509,9 @@ static int rbd_add_parse_args(struct rbd_device *rbd_dev, len = copy_token(&buf, options, options_size); if (!len || len >= options_size) - return -EINVAL; + return err_ptr; - ret = -ENOMEM; + err_ptr = ERR_PTR(-ENOMEM); rbd_dev->pool_name = dup_token(&buf, NULL); if (!rbd_dev->pool_name) goto out_err; @@ -2526,26 +2529,21 @@ static int rbd_add_parse_args(struct rbd_device *rbd_dev, goto out_err; sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); - /* - * The snapshot name is optional. If none is is supplied, - * we use the default value. - */ - rbd_dev->mapping.snap_name = dup_token(&buf, &len); - if (!rbd_dev->mapping.snap_name) - goto out_err; + /* Snapshot name is optional */ + len = next_token(&buf); if (!len) { - /* Replace the empty name with the default */ - kfree(rbd_dev->mapping.snap_name); - rbd_dev->mapping.snap_name - = kmalloc(sizeof (RBD_SNAP_HEAD_NAME), GFP_KERNEL); - if (!rbd_dev->mapping.snap_name) - goto out_err; - - memcpy(rbd_dev->mapping.snap_name, RBD_SNAP_HEAD_NAME, - sizeof (RBD_SNAP_HEAD_NAME)); + buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ + len = sizeof (RBD_SNAP_HEAD_NAME) - 1; } + snap_name = kmalloc(len + 1, GFP_KERNEL); + if (!snap_name) + goto out_err; + memcpy(snap_name, buf, len); + *(snap_name + len) = '\0'; - return 0; +dout(" SNAP_NAME is <%s>, len is %zd\n", snap_name, len); + + return snap_name; out_err: kfree(rbd_dev->header_name); @@ -2556,7 +2554,7 @@ out_err: kfree(rbd_dev->pool_name); rbd_dev->pool_name = NULL; - return ret; + return err_ptr; } static ssize_t rbd_add(struct bus_type *bus, @@ -2569,6 +2567,7 @@ static ssize_t rbd_add(struct bus_type *bus, size_t mon_addrs_size = 0; struct ceph_osd_client *osdc; int rc = -ENOMEM; + char *snap_name; if (!try_module_get(THIS_MODULE)) return -ENODEV; @@ -2595,10 +2594,13 @@ static ssize_t rbd_add(struct bus_type *bus, sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id); /* parse add command */ - rc = rbd_add_parse_args(rbd_dev, buf, &mon_addrs, &mon_addrs_size, - options, count); - if (rc) + snap_name = rbd_add_parse_args(rbd_dev, buf, + &mon_addrs, &mon_addrs_size, options, count); + if (IS_ERR(snap_name)) { + rc = PTR_ERR(snap_name); goto err_put_id; + } + rbd_dev->mapping.snap_name = snap_name; rc = rbd_get_client(rbd_dev, mon_addrs, mon_addrs_size - 1, options); if (rc < 0) -- 2.20.1