5 files changed, 12 insertions, 41 deletions

diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index b1fc28f63882..d0b63bbf46a7 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -244,7 +244,7 @@ static int ubiblock_open(struct block_device *bdev, fmode_t mode)
 	 * in any case.
 	 */
 	if (mode & FMODE_WRITE) {
-		ret = -EPERM;
+		ret = -EROFS;
 		goto out_unlock;
 	}
 
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index e941395de3ae..753494e042d5 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -854,6 +854,17 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 		return -EINVAL;
 	}
 
+	/*
+	 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
+	 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
+	 * will die soon and you will lose all your data.
+	 */
+	if (mtd->type == MTD_MLCNANDFLASH) {
+		pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
+			mtd->index);
+		return -EINVAL;
+	}
+
 	if (ubi_num == UBI_DEV_NUM_AUTO) {
 		/* Search for an empty slot in the @ubi_devices array */
 		for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
diff --git a/drivers/mtd/ubi/fastmap-wl.c b/drivers/mtd/ubi/fastmap-wl.c
index 590d967011bb..98f7d6be8d1f 100644
--- a/drivers/mtd/ubi/fastmap-wl.c
+++ b/drivers/mtd/ubi/fastmap-wl.c
@@ -362,7 +362,6 @@ static void ubi_fastmap_close(struct ubi_device *ubi)
 {
 	int i;
 
-	flush_work(&ubi->fm_work);
 	return_unused_pool_pebs(ubi, &ubi->fm_pool);
 	return_unused_pool_pebs(ubi, &ubi->fm_wl_pool);
 
diff --git a/drivers/mtd/ubi/gluebi.c b/drivers/mtd/ubi/gluebi.c
index 1cb287ec32ad..6b655a53113b 100644
--- a/drivers/mtd/ubi/gluebi.c
+++ b/drivers/mtd/ubi/gluebi.c
@@ -272,12 +272,9 @@ static int gluebi_erase(struct mtd_info *mtd, struct erase_info *instr)
 	if (err)
 		goto out_err;
 
-	instr->state = MTD_ERASE_DONE;
-	mtd_erase_callback(instr);
 	return 0;
 
 out_err:
-	instr->state = MTD_ERASE_FAILED;
 	instr->fail_addr = (long long)lnum * mtd->erasesize;
 	return err;
 }
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index 8290432017ce..0e3a76a9e2f8 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -309,18 +309,6 @@ int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
 }
 
 /**
- * erase_callback - MTD erasure call-back.
- * @ei: MTD erase information object.
- *
- * Note, even though MTD erase interface is asynchronous, all the current
- * implementations are synchronous anyway.
- */
-static void erase_callback(struct erase_info *ei)
-{
-	wake_up_interruptible((wait_queue_head_t *)ei->priv);
-}
-
-/**
  * do_sync_erase - synchronously erase a physical eraseblock.
  * @ubi: UBI device description object
  * @pnum: the physical eraseblock number to erase
@@ -333,7 +321,6 @@ static int do_sync_erase(struct ubi_device *ubi, int pnum)
 {
 	int err, retries = 0;
 	struct erase_info ei;
-	wait_queue_head_t wq;
 
 	dbg_io("erase PEB %d", pnum);
 	ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
@@ -344,14 +331,10 @@ static int do_sync_erase(struct ubi_device *ubi, int pnum)
 	}
 
 retry:
-	init_waitqueue_head(&wq);
 	memset(&ei, 0, sizeof(struct erase_info));
 
-	ei.mtd      = ubi->mtd;
 	ei.addr     = (loff_t)pnum * ubi->peb_size;
 	ei.len      = ubi->peb_size;
-	ei.callback = erase_callback;
-	ei.priv     = (unsigned long)&wq;
 
 	err = mtd_erase(ubi->mtd, &ei);
 	if (err) {
@@ -366,25 +349,6 @@ retry:
 		return err;
 	}
 
-	err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE ||
-					   ei.state == MTD_ERASE_FAILED);
-	if (err) {
-		ubi_err(ubi, "interrupted PEB %d erasure", pnum);
-		return -EINTR;
-	}
-
-	if (ei.state == MTD_ERASE_FAILED) {
-		if (retries++ < UBI_IO_RETRIES) {
-			ubi_warn(ubi, "error while erasing PEB %d, retry",
-				 pnum);
-			yield();
-			goto retry;
-		}
-		ubi_err(ubi, "cannot erase PEB %d", pnum);
-		dump_stack();
-		return -EIO;
-	}
-
 	err = ubi_self_check_all_ff(ubi, pnum, 0, ubi->peb_size);
 	if (err)
 		return err;