OpenWrt – Rev 1
?pathlinks?
From: Daniel Golle <daniel@makrotopia.org>
Subject: ubi: auto-attach mtd device named "ubi" or "data" on boot
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
drivers/mtd/ubi/build.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1226,6 +1226,73 @@ static struct mtd_info * __init open_mtd
return mtd;
}
+/*
+ * This function tries attaching mtd partitions named either "ubi" or "data"
+ * during boot.
+ */
+static void __init ubi_auto_attach(void)
+{
+ int err;
+ struct mtd_info *mtd;
+ loff_t offset = 0;
+ size_t len;
+ char magic[4];
+
+ /* try attaching mtd device named "ubi" or "data" */
+ mtd = open_mtd_device("ubi");
+ if (IS_ERR(mtd))
+ mtd = open_mtd_device("data");
+
+ if (IS_ERR(mtd))
+ return;
+
+ /* get the first not bad block */
+ if (mtd_can_have_bb(mtd))
+ while (mtd_block_isbad(mtd, offset)) {
+ offset += mtd->erasesize;
+
+ if (offset > mtd->size) {
+ pr_err("UBI error: Failed to find a non-bad "
+ "block on mtd%d\n", mtd->index);
+ goto cleanup;
+ }
+ }
+
+ /* check if the read from flash was successful */
+ err = mtd_read(mtd, offset, 4, &len, (void *) magic);
+ if ((err && !mtd_is_bitflip(err)) || len != 4) {
+ pr_err("UBI error: unable to read from mtd%d\n", mtd->index);
+ goto cleanup;
+ }
+
+ /* check for a valid ubi magic */
+ if (strncmp(magic, "UBI#", 4)) {
+ pr_err("UBI error: no valid UBI magic found inside mtd%d\n", mtd->index);
+ goto cleanup;
+ }
+
+ /* don't auto-add media types where UBI doesn't makes sense */
+ if (mtd->type != MTD_NANDFLASH &&
+ mtd->type != MTD_NORFLASH &&
+ mtd->type != MTD_DATAFLASH &&
+ mtd->type != MTD_MLCNANDFLASH)
+ goto cleanup;
+
+ mutex_lock(&ubi_devices_mutex);
+ pr_notice("UBI: auto-attach mtd%d\n", mtd->index);
+ err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0);
+ mutex_unlock(&ubi_devices_mutex);
+ if (err < 0) {
+ pr_err("UBI error: cannot attach mtd%d\n", mtd->index);
+ goto cleanup;
+ }
+
+ return;
+
+cleanup:
+ put_mtd_device(mtd);
+}
+
static int __init ubi_init(void)
{
int err, i, k;
@@ -1309,6 +1376,12 @@ static int __init ubi_init(void)
}
}
+ /* auto-attach mtd devices only if built-in to the kernel and no ubi.mtd
+ * parameter was given */
+ if (IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
+ !ubi_is_module() && !mtd_devs)
+ ubi_auto_attach();
+
err = ubiblock_init();
if (err) {
pr_err("UBI error: block: cannot initialize, error %d", err);