UBI: support ubi_num on mtd.ubi command line

I want to be able to add UBI volumes with specific numbers, but the
command line API doesn't have that atm.  Add an additional token to
support it.

Artem: amended the patch a little bit.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

1 files changed, 28 insertions, 11 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 8ff08ecb9383..a3503821d0c7 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -47,7 +47,7 @@
 #define MTD_PARAM_LEN_MAX 64
 
 /* Maximum number of comma-separated items in the 'mtd=' parameter */
-#define MTD_PARAM_MAX_COUNT 3
+#define MTD_PARAM_MAX_COUNT 4
 
 /* Maximum value for the number of bad PEBs per 1024 PEBs */
 #define MAX_MTD_UBI_BEB_LIMIT 768
@@ -67,6 +67,7 @@
  */
 struct mtd_dev_param {
         char name[MTD_PARAM_LEN_MAX];
+        int ubi_num;
         int vid_hdr_offs;
         int max_beb_per1024;
 };
@@ -1269,7 +1270,7 @@ static int __init ubi_init(void)
                 }
 
                 mutex_lock(&ubi_devices_mutex);
-                err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
+                err = ubi_attach_mtd_dev(mtd, p->ubi_num,
                                          p->vid_hdr_offs, p->max_beb_per1024);
                 mutex_unlock(&ubi_devices_mutex);
                 if (err < 0) {
@@ -1387,7 +1388,7 @@ static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
         struct mtd_dev_param *p;
         char buf[MTD_PARAM_LEN_MAX];
         char *pbuf = &buf[0];
-        char *tokens[MTD_PARAM_MAX_COUNT];
+        char *tokens[MTD_PARAM_MAX_COUNT], *token;
 
         if (!val)
                 return -EINVAL;
@@ -1427,37 +1428,53 @@ static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
         p = &mtd_dev_param[mtd_devs];
         strcpy(&p->name[0], tokens[0]);
 
-        if (tokens[1])
-                p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
+        token = tokens[1];
+        if (token) {
+                p->vid_hdr_offs = bytes_str_to_int(token);
 
-        if (p->vid_hdr_offs < 0)
-                return p->vid_hdr_offs;
+                if (p->vid_hdr_offs < 0)
+                        return p->vid_hdr_offs;
+        }
 
-        if (tokens[2]) {
-                int err = kstrtoint(tokens[2], 10, &p->max_beb_per1024);
+        token = tokens[2];
+        if (token) {
+                int err = kstrtoint(token, 10, &p->max_beb_per1024);
 
                 if (err) {
                         ubi_err("bad value for max_beb_per1024 parameter: %s",
-                                tokens[2]);
+                                token);
                         return -EINVAL;
                 }
         }
 
+        token = tokens[3];
+        if (token) {
+                int err = kstrtoint(token, 10, &p->ubi_num);
+
+                if (err) {
+                        ubi_err("bad value for ubi_num parameter: %s", token);
+                        return -EINVAL;
+                }
+        } else
+                p->ubi_num = UBI_DEV_NUM_AUTO;
+
         mtd_devs += 1;
         return 0;
 }
 
 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
-MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024]].\n"
+MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
                       "Multiple \"mtd\" parameters may be specified.\n"
                       "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
                       "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
                       "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
                       __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
+                      "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
                       "\n"
                       "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
                       "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"
                       "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n"
+                      "Example 4: mtd=/dev/mtd1,0,0,5 - attach MTD device /dev/mtd1 to UBI 5 and using default values for the other fields.\n"
                       "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
 #ifdef CONFIG_MTD_UBI_FASTMAP
 module_param(fm_autoconvert, bool, 0644);