x86: try harder to attach block2mtd to fix boot issues on devices with longer delays

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 40444

1 files changed, 104 insertions, 6 deletions

diff --git a/target/linux/generic/patches-3.14/441-block2mtd_probe.patch b/target/linux/generic/patches-3.14/441-block2mtd_probe.patch
index 0b2e80c..3ab9d1a 100644
--- a/target/linux/generic/patches-3.14/441-block2mtd_probe.patch
+++ b/target/linux/generic/patches-3.14/441-block2mtd_probe.patch
@@ -1,10 +1,108 @@
 --- a/drivers/mtd/devices/block2mtd.c
 +++ b/drivers/mtd/devices/block2mtd.c
-@@ -234,6 +234,7 @@ static struct block2mtd_dev *add_device(
- 		/* We might not have rootfs mounted at this point. Try
- 		   to resolve the device name by other means. */
+@@ -10,6 +10,7 @@
+ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
+ #include <linux/module.h>
++#include <linux/delay.h>
+ #include <linux/fs.h>
+ #include <linux/blkdev.h>
+ #include <linux/bio.h>
+@@ -211,13 +212,14 @@ static void block2mtd_free_device(struct
+ 
+ 
+ /* FIXME: ensure that mtd->size % erase_size == 0 */
+-static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname)
++static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname, int timeout)
+ {
+ 	const fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL;
+-	struct block_device *bdev;
++	struct block_device *bdev = ERR_PTR(-ENODEV);
+ 	struct block2mtd_dev *dev;
+ 	struct mtd_partition *part;
+ 	char *name;
++	int i;
+ 
+ 	if (!devname)
+ 		return NULL;
+@@ -228,15 +230,20 @@ static struct block2mtd_dev *add_device(
+ 
+ 	/* Get a handle on the device */
+ 	bdev = blkdev_get_by_path(devname, mode, dev);
++
+ #ifndef MODULE
+-	if (IS_ERR(bdev)) {
++	for (i = 0; IS_ERR(bdev) && i <= timeout; i++) {
++		dev_t devt;
+ 
+-		/* We might not have rootfs mounted at this point. Try
+-		   to resolve the device name by other means. */
++		if (i)
++			msleep(1000);
 +		wait_for_device_probe();
- 		dev_t devt = name_to_dev_t(devname);
- 		if (devt)
- 			bdev = blkdev_get_by_dev(devt, mode, dev);
++
++		devt = name_to_dev_t(devname);
++		if (!devt)
++			continue;
+ 
+-		dev_t devt = name_to_dev_t(devname);
+-		if (devt)
+-			bdev = blkdev_get_by_dev(devt, mode, dev);
++		bdev = blkdev_get_by_dev(devt, mode, dev);
+ 	}
+ #endif
+ 
+@@ -355,11 +362,12 @@ static char block2mtd_paramline[80 + 12]
+ 
+ static int block2mtd_setup2(const char *val)
+ {
+-	char buf[80 + 12 + 80]; /* 80 for device, 12 for erase size, 80 for name */
++	char buf[80 + 12 + 80 + 8]; /* 80 for device, 12 for erase size, 80 for name, 8 for timeout */
+ 	char *str = buf;
+-	char *token[3];
++	char *token[4];
+ 	char *name;
+ 	size_t erase_size = PAGE_SIZE;
++	unsigned long timeout = 0;
+ 	int i, ret;
+ 
+ 	if (strnlen(val, sizeof(buf)) >= sizeof(buf)) {
+@@ -370,7 +378,7 @@ static int block2mtd_setup2(const char *
+ 	strcpy(str, val);
+ 	kill_final_newline(str);
+ 
+-	for (i = 0; i < 3; i++)
++	for (i = 0; i < 4; i++)
+ 		token[i] = strsep(&str, ",");
+ 
+ 	if (str) {
+@@ -399,7 +407,10 @@ static int block2mtd_setup2(const char *
+ 	if (token[2] && (strlen(token[2]) + 1 > 80))
+ 		pr_err("mtd device name too long\n");
+ 
+-	add_device(name, erase_size, token[2]);
++	if (token[3] && kstrtoul(token[3], 0, &timeout))
++		pr_err("invalid timeout\n");
++
++	add_device(name, erase_size, token[2], timeout);
+ 
+ 	return 0;
+ }
+@@ -433,7 +444,7 @@ static int block2mtd_setup(const char *v
+ 
+ 
+ module_param_call(block2mtd, block2mtd_setup, NULL, NULL, 0200);
+-MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=<dev>[,<erasesize>[,<name>]]\"");
++MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=<dev>[,<erasesize>[,<name>[,<timeout>]]]\"");
+ 
+ static int __init block2mtd_init(void)
+ {
+@@ -467,7 +478,7 @@ static void block2mtd_exit(void)
+ }
+ 
+ 
+-module_init(block2mtd_init);
++late_initcall(block2mtd_init);
+ module_exit(block2mtd_exit);
+ 
+ MODULE_LICENSE("GPL");