UBI: fix autoresize handling in R/O mode

[pandora-kernel.git] / drivers / mtd / ubi / build.c

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 8a4eb7c..8966088 100644 (file)
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -47,7 +47,10 @@
 #define MTD_PARAM_LEN_MAX 64
 
 /* Maximum number of comma-separated items in the 'mtd=' parameter */
-#define MTD_PARAM_MAX_COUNT 2
+#define MTD_PARAM_MAX_COUNT 3
+
+/* Maximum value for the number of bad PEBs per 1024 PEBs */
+#define MAX_MTD_UBI_BEB_LIMIT 768
 
 #ifdef CONFIG_MTD_UBI_MODULE
 #define ubi_is_module() 1
@@ -60,10 +63,12 @@
  * @name: MTD character device node path, MTD device name, or MTD device number
  *        string
  * @vid_hdr_offs: VID header offset
+ * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
  */
 struct mtd_dev_param {
        char name[MTD_PARAM_LEN_MAX];
        int vid_hdr_offs;
+       int max_beb_per1024;
 };
 
 /* Numbers of elements set in the @mtd_dev_param array */
@@ -794,6 +799,11 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
        struct ubi_volume *vol = ubi->volumes[vol_id];
        int err, old_reserved_pebs = vol->reserved_pebs;
 
+       if (ubi->ro_mode) {
+               ubi_warn("skip auto-resize because of R/O mode");
+               return 0;
+       }
+
        /*
         * Clear the auto-resize flag in the volume in-memory copy of the
         * volume table, and 'ubi_resize_volume()' will propagate this change
@@ -835,7 +845,7 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
  * @mtd: MTD device description object
  * @ubi_num: number to assign to the new UBI device
  * @vid_hdr_offset: VID header offset
- * @max_beb_per1024: maximum number of expected bad blocks per 1024 PEBs
+ * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
  *
  * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
  * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
@@ -852,6 +862,12 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
        struct ubi_device *ubi;
        int i, err, ref = 0;
 
+       if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
+               return -EINVAL;
+
+       if (!max_beb_per1024)
+               max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
+
        /*
         * Check if we already have the same MTD device attached.
         *
@@ -1209,8 +1225,7 @@ static int __init ubi_init(void)
 
                mutex_lock(&ubi_devices_mutex);
                err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
-                                        p->vid_hdr_offs,
-                                        CONFIG_MTD_UBI_BEB_LIMIT);
+                                        p->vid_hdr_offs, p->max_beb_per1024);
                mutex_unlock(&ubi_devices_mutex);
                if (err < 0) {
                        ubi_err("cannot attach mtd%d", mtd->index);
@@ -1377,23 +1392,32 @@ static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
        if (p->vid_hdr_offs < 0)
                return p->vid_hdr_offs;
 
+       if (tokens[2]) {
+               int err = kstrtoint(tokens[2], 10, &p->max_beb_per1024);
+
+               if (err) {
+                       printk(KERN_ERR "UBI error: bad value for "
+                              "max_beb_per1024 parameter: %s", tokens[2]);
+                       return -EINVAL;
+               }
+       }
+
        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>].\n"
+MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024]].\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.\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.");
+                     "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"
+                     "\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"
+                     "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
 
 MODULE_VERSION(__stringify(UBI_VERSION));
 MODULE_DESCRIPTION("UBI - Unsorted Block Images");