rbd: add warning messages for missing arguments

Tell the user (via dmesg) what was wrong with the arguments provided
via /sys/bus/rbd/add.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 635b81d..31da8c5 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -3244,8 +3244,10 @@ static int rbd_add_parse_args(const char *buf,
        /* The first four tokens are required */
 
        len = next_token(&buf);
-       if (!len)
-               return -EINVAL; /* Missing monitor address(es) */
+       if (!len) {
+               rbd_warn(NULL, "no monitor address(es) provided");
+               return -EINVAL;
+       }
        mon_addrs = buf;
        mon_addrs_size = len + 1;
        buf += len;
@@ -3254,8 +3256,10 @@ static int rbd_add_parse_args(const char *buf,
        options = dup_token(&buf, NULL);
        if (!options)
                return -ENOMEM;
-       if (!*options)
-               goto out_err;   /* Missing options */
+       if (!*options) {
+               rbd_warn(NULL, "no options provided");
+               goto out_err;
+       }
 
        spec = rbd_spec_alloc();
        if (!spec)
@@ -3264,14 +3268,18 @@ static int rbd_add_parse_args(const char *buf,
        spec->pool_name = dup_token(&buf, NULL);
        if (!spec->pool_name)
                goto out_mem;
-       if (!*spec->pool_name)
-               goto out_err;   /* Missing pool name */
+       if (!*spec->pool_name) {
+               rbd_warn(NULL, "no pool name provided");
+               goto out_err;
+       }
 
        spec->image_name = dup_token(&buf, NULL);
        if (!spec->image_name)
                goto out_mem;
-       if (!*spec->image_name)
-               goto out_err;   /* Missing image name */
+       if (!*spec->image_name) {
+               rbd_warn(NULL, "no image name provided");
+               goto out_err;
+       }
 
        /*
         * Snapshot name is optional; default is to use "-"