md: allow integers to be passed to md/level

e.g. allow md to interpret 'echo 4 > md/level' as a request for raid4.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 14 insertions, 10 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 69f659e46aa6..b8a0fcfb1de1 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2934,9 +2934,10 @@ level_show(mddev_t *mddev, char *page)
 static ssize_t
 level_store(mddev_t *mddev, const char *buf, size_t len)
 {
-        char level[16];
+        char clevel[16];
         ssize_t rv = len;
         struct mdk_personality *pers;
+        long level;
         void *priv;
         mdk_rdev_t *rdev;
 
@@ -2969,19 +2970,22 @@ level_store(mddev_t *mddev, const char *buf, size_t len)
         }
 
         /* Now find the new personality */
-        if (len == 0 || len >= sizeof(level))
+        if (len == 0 || len >= sizeof(clevel))
                 return -EINVAL;
-        strncpy(level, buf, len);
-        if (level[len-1] == '\n')
+        strncpy(clevel, buf, len);
+        if (clevel[len-1] == '\n')
                 len--;
-        level[len] = 0;
+        clevel[len] = 0;
+        if (strict_strtol(clevel, 10, &level))
+                level = LEVEL_NONE;
 
-        request_module("md-%s", level);
+        if (request_module("md-%s", clevel) != 0)
+                request_module("md-level-%s", clevel);
         spin_lock(&pers_lock);
-        pers = find_pers(LEVEL_NONE, level);
+        pers = find_pers(level, clevel);
         if (!pers || !try_module_get(pers->owner)) {
                 spin_unlock(&pers_lock);
-                printk(KERN_WARNING "md: personality %s not loaded\n", level);
+                printk(KERN_WARNING "md: personality %s not loaded\n", clevel);
                 return -EINVAL;
         }
         spin_unlock(&pers_lock);
@@ -2994,7 +2998,7 @@ level_store(mddev_t *mddev, const char *buf, size_t len)
         if (!pers->takeover) {
                 module_put(pers->owner);
                 printk(KERN_WARNING "md: %s: %s does not support personality takeover\n",
-                       mdname(mddev), level);
+                       mdname(mddev), clevel);
                 return -EINVAL;
         }
 
@@ -3010,7 +3014,7 @@ level_store(mddev_t *mddev, const char *buf, size_t len)
                 mddev->delta_disks = 0;
                 module_put(pers->owner);
                 printk(KERN_WARNING "md: %s: %s would not accept array\n",
-                       mdname(mddev), level);
+                       mdname(mddev), clevel);
                 return PTR_ERR(priv);
         }