[]

[Joachim Wiberg]

commit 72282e537222988d1dfa787e79554d136fd1fc56
Author: Joachim Wiberg <troglobit at gmail.com>
Date:   Wed Nov 18 16:38:13 2015 +0100

    mtd: mtd2block: add support for an optional custom MTD label
    
    This patch adds support for an optional MTD label for mtd2block emulated
    MTD devices.  Useful when, e.g. testing device images using Qemu.  The
    following /etc/fstab line in can then be used to mount a file system
    regardless of the actual MTD partition number:
    
        mtd:Config  /mnt    jffs2   noatime,nodiratime      0    0
    
    Kernel command line syntax:
    
        block2mtd.block2mtd=/dev/sda,,Config
    
    The ',,' is the optional erase_size, which like before this patch,
    defaults to PAGE_SIZE if left out.
    
    Signed-off-by: Joachim Wiberg <troglobit at gmail.com>

diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index c9e424993e37..f9c14146bf9c 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -214,7 +214,7 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
 
 
 static struct block2mtd_dev *add_device(char *devname, int erase_size,
-		int timeout)
+		char *label, int timeout)
 {
 #ifndef MODULE
 	int i;
@@ -278,7 +278,10 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size,
 
 	/* Setup the MTD structure */
 	/* make the name contain the block device in */
-	name = kasprintf(GFP_KERNEL, "block2mtd: %s", devname);
+	if (!label)
+		name = kasprintf(GFP_KERNEL, "block2mtd: %s", devname);
+	else
+		name = kstrdup(label, GFP_KERNEL);
 	if (!name)
 		goto err_destroy_mutex;
 
@@ -379,8 +382,8 @@ static int block2mtd_setup2(const char *val)
 	/* 80 for device, 12 for erase size, 80 for name, 8 for timeout */
 	char buf[80 + 12 + 80 + 8];
 	char *str = buf;
-	char *token[2];
-	char *name;
+	char *token[3];
+	char *name, *label = NULL;
 	size_t erase_size = PAGE_SIZE;
 	unsigned long timeout = MTD_DEFAULT_TIMEOUT;
 	int i, ret;
@@ -393,7 +396,7 @@ static int block2mtd_setup2(const char *val)
 	strcpy(str, val);
 	kill_final_newline(str);
 
-	for (i = 0; i < 2; i++)
+	for (i = 0; i < 3; i++)
 		token[i] = strsep(&str, ",");
 
 	if (str) {
@@ -412,7 +415,7 @@ static int block2mtd_setup2(const char *val)
 		return 0;
 	}
 
-	if (token[1]) {
+	if (token[1] && strlen(token[1])) {
 		ret = parse_num(&erase_size, token[1]);
 		if (ret) {
 			pr_err("illegal erase size\n");
@@ -420,7 +423,12 @@ static int block2mtd_setup2(const char *val)
 		}
 	}
 
-	add_device(name, erase_size, timeout);
+	if (token[2]) {
+		label = token[2];
+		pr_info("Using custom MTD label '%s' for dev %s\n", label, name);
+	}
+
+	add_device(name, erase_size, label, timeout);
 
 	return 0;
 }
@@ -454,7 +462,7 @@ static int block2mtd_setup(const char *val, const struct kernel_param *kp)
 
 
 module_param_call(block2mtd, block2mtd_setup, NULL, NULL, 0200);
-MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=<dev>[,<erasesize>]\"");
+MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=<dev>[,[<erasesize>][,<name>]]\"");
 
 static int __init block2mtd_init(void)
 {