mtd: Stop assuming mtd_erase() is asynchronous

None of the mtd->_erase() implementations work in an asynchronous manner,
so let's simplify MTD users that call mtd_erase(). All they need to do
is check the value returned by mtd_erase() and assume that != 0 means
failure.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>

17 files changed, 47 insertions, 337 deletions

diff --git a/drivers/mtd/devices/bcm47xxsflash.c b/drivers/mtd/devices/bcm47xxsflash.c
index e2bd81817df4..6b84947cfbea 100644
--- a/drivers/mtd/devices/bcm47xxsflash.c
+++ b/drivers/mtd/devices/bcm47xxsflash.c
@@ -95,9 +95,6 @@ static int bcm47xxsflash_erase(struct mtd_info *mtd, struct erase_info *erase)
 	else
 		erase->state = MTD_ERASE_DONE;
 
-	if (erase->callback)
-		erase->callback(erase);
-
 	return err;
 }
 
diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c
index 664d206a4cbe..fcf9907e7987 100644
--- a/drivers/mtd/ftl.c
+++ b/drivers/mtd/ftl.c
@@ -140,12 +140,6 @@ typedef struct partition_t {
 #define XFER_PREPARED	0x03
 #define XFER_FAILED	0x04
 
-/*====================================================================*/
-
-
-static void ftl_erase_callback(struct erase_info *done);
-
-
 /*======================================================================
 
     Scan_header() checks to see if a memory region contains an FTL
@@ -349,17 +343,19 @@ static int erase_xfer(partition_t *part,
             return -ENOMEM;
 
     erase->mtd = part->mbd.mtd;
-    erase->callback = ftl_erase_callback;
     erase->addr = xfer->Offset;
     erase->len = 1 << part->header.EraseUnitSize;
-    erase->priv = (u_long)part;
 
     ret = mtd_erase(part->mbd.mtd, erase);
+    if (!ret) {
+	xfer->state = XFER_ERASED;
+	xfer->EraseCount++;
+    } else {
+	xfer->state = XFER_FAILED;
+	pr_notice("ftl_cs: erase failed: err = %d\n", ret);
+    }
 
-    if (!ret)
-	    xfer->EraseCount++;
-    else
-	    kfree(erase);
+    kfree(erase);
 
     return ret;
 } /* erase_xfer */
@@ -371,37 +367,6 @@ static int erase_xfer(partition_t *part,
 
 ======================================================================*/
 
-static void ftl_erase_callback(struct erase_info *erase)
-{
-    partition_t *part;
-    struct xfer_info_t *xfer;
-    int i;
-
-    /* Look up the transfer unit */
-    part = (partition_t *)(erase->priv);
-
-    for (i = 0; i < part->header.NumTransferUnits; i++)
-	if (part->XferInfo[i].Offset == erase->addr) break;
-
-    if (i == part->header.NumTransferUnits) {
-	printk(KERN_NOTICE "ftl_cs: internal error: "
-	       "erase lookup failed!\n");
-	return;
-    }
-
-    xfer = &part->XferInfo[i];
-    if (erase->state == MTD_ERASE_DONE)
-	xfer->state = XFER_ERASED;
-    else {
-	xfer->state = XFER_FAILED;
-	printk(KERN_NOTICE "ftl_cs: erase failed: state = %d\n",
-	       erase->state);
-    }
-
-    kfree(erase);
-
-} /* ftl_erase_callback */
-
 static int prepare_xfer(partition_t *part, int i)
 {
     erase_unit_header_t header;
diff --git a/drivers/mtd/inftlmount.c b/drivers/mtd/inftlmount.c
index 8d6bb189ea8e..0f47be4834d8 100644
--- a/drivers/mtd/inftlmount.c
+++ b/drivers/mtd/inftlmount.c
@@ -393,9 +393,10 @@ int INFTL_formatblock(struct INFTLrecord *inftl, int block)
 	   mark only the failed block in the bbt. */
 	for (physblock = 0; physblock < inftl->EraseSize;
 	     physblock += instr->len, instr->addr += instr->len) {
-		mtd_erase(inftl->mbd.mtd, instr);
+		int ret;
 
-		if (instr->state == MTD_ERASE_FAILED) {
+		ret = mtd_erase(inftl->mbd.mtd, instr);
+		if (ret) {
 			printk(KERN_WARNING "INFTL: error while formatting block %d\n",
 				block);
 			goto fail;
diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
index bb4c14f83c75..7b2b7f651181 100644
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -55,48 +55,28 @@ struct mtdblk_dev {
  * being written to until a different sector is required.
  */
 
-static void erase_callback(struct erase_info *done)
-{
-	wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
-	wake_up(wait_q);
-}
-
 static int erase_write (struct mtd_info *mtd, unsigned long pos,
 			int len, const char *buf)
 {
 	struct erase_info erase;
-	DECLARE_WAITQUEUE(wait, current);
-	wait_queue_head_t wait_q;
 	size_t retlen;
 	int ret;
 
 	/*
 	 * First, let's erase the flash block.
 	 */
-
-	init_waitqueue_head(&wait_q);
 	erase.mtd = mtd;
-	erase.callback = erase_callback;
 	erase.addr = pos;
 	erase.len = len;
-	erase.priv = (u_long)&wait_q;
-
-	set_current_state(TASK_INTERRUPTIBLE);
-	add_wait_queue(&wait_q, &wait);
 
 	ret = mtd_erase(mtd, &erase);
 	if (ret) {
-		set_current_state(TASK_RUNNING);
-		remove_wait_queue(&wait_q, &wait);
 		printk (KERN_WARNING "mtdblock: erase of region [0x%lx, 0x%x] "
 				     "on \"%s\" failed\n",
 			pos, len, mtd->name);
 		return ret;
 	}
 
-	schedule();  /* Wait for erase to finish. */
-	remove_wait_queue(&wait_q, &wait);
-
 	/*
 	 * Next, write the data to flash.
 	 */
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index de8c902059b8..2beb22dd6bbb 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -324,10 +324,6 @@ static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t c
     IOCTL calls for getting device parameters.
 
 ======================================================================*/
-static void mtdchar_erase_callback (struct erase_info *instr)
-{
-	wake_up((wait_queue_head_t *)instr->priv);
-}
 
 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 {
@@ -709,11 +705,6 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 		if (!erase)
 			ret = -ENOMEM;
 		else {
-			wait_queue_head_t waitq;
-			DECLARE_WAITQUEUE(wait, current);
-
-			init_waitqueue_head(&waitq);
-
 			if (cmd == MEMERASE64) {
 				struct erase_info_user64 einfo64;
 
@@ -736,30 +727,8 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 				erase->len = einfo32.length;
 			}
 			erase->mtd = mtd;
-			erase->callback = mtdchar_erase_callback;
-			erase->priv = (unsigned long)&waitq;
-
-			/*
-			  FIXME: Allow INTERRUPTIBLE. Which means
-			  not having the wait_queue head on the stack.
-
-			  If the wq_head is on the stack, and we
-			  leave because we got interrupted, then the
-			  wq_head is no longer there when the
-			  callback routine tries to wake us up.
-			*/
+
 			ret = mtd_erase(mtd, erase);
-			if (!ret) {
-				set_current_state(TASK_UNINTERRUPTIBLE);
-				add_wait_queue(&waitq, &wait);
-				if (erase->state != MTD_ERASE_DONE &&
-				    erase->state != MTD_ERASE_FAILED)
-					schedule();
-				remove_wait_queue(&waitq, &wait);
-				set_current_state(TASK_RUNNING);
-
-				ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
-			}
 			kfree(erase);
 		}
 		break;
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 60bf53df5454..caa09bf6e572 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -333,45 +333,6 @@ concat_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops)
 	return -EINVAL;
 }
 
-static void concat_erase_callback(struct erase_info *instr)
-{
-	wake_up((wait_queue_head_t *) instr->priv);
-}
-
-static int concat_dev_erase(struct mtd_info *mtd, struct erase_info *erase)
-{
-	int err;
-	wait_queue_head_t waitq;
-	DECLARE_WAITQUEUE(wait, current);
-
-	/*
-	 * This code was stol^H^H^H^Hinspired by mtdchar.c
-	 */
-	init_waitqueue_head(&waitq);
-
-	erase->mtd = mtd;
-	erase->callback = concat_erase_callback;
-	erase->priv = (unsigned long) &waitq;
-
-	/*
-	 * FIXME: Allow INTERRUPTIBLE. Which means
-	 * not having the wait_queue head on the stack.
-	 */
-	err = mtd_erase(mtd, erase);
-	if (!err) {
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		add_wait_queue(&waitq, &wait);
-		if (erase->state != MTD_ERASE_DONE
-		    && erase->state != MTD_ERASE_FAILED)
-			schedule();
-		remove_wait_queue(&waitq, &wait);
-		set_current_state(TASK_RUNNING);
-
-		err = (erase->state == MTD_ERASE_FAILED) ? -EIO : 0;
-	}
-	return err;
-}
-
 static int concat_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
 	struct mtd_concat *concat = CONCAT(mtd);
@@ -466,7 +427,8 @@ static int concat_erase(struct mtd_info *mtd, struct erase_info *instr)
 			erase->len = length;
 
 		length -= erase->len;
-		if ((err = concat_dev_erase(subdev, erase))) {
+		erase->mtd = subdev;
+		if ((err = mtd_erase(subdev, erase))) {
 			/* sanity check: should never happen since
 			 * block alignment has been checked above */
 			BUG_ON(err == -EINVAL);
@@ -487,12 +449,8 @@ static int concat_erase(struct mtd_info *mtd, struct erase_info *instr)
 	}
 	instr->state = erase->state;
 	kfree(erase);
-	if (err)
-		return err;
 
-	if (instr->callback)
-		instr->callback(instr);
-	return 0;
+	return err;
 }
 
 static int concat_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index c87859ff338b..f92ad02959eb 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -945,11 +945,9 @@ void __put_mtd_device(struct mtd_info *mtd)
 EXPORT_SYMBOL_GPL(__put_mtd_device);
 
 /*
- * Erase is an asynchronous operation.  Device drivers are supposed
- * to call instr->callback() whenever the operation completes, even
- * if it completes with a failure.
- * Callers are supposed to pass a callback function and wait for it
- * to be called before writing to the block.
+ * Erase is an synchronous operation. Device drivers are epected to return a
+ * negative error code if the operation failed and update instr->fail_addr
+ * to point the portion that was not properly erased.
  */
 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index 97bb8f6304d4..028ded59297b 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -84,12 +84,6 @@ static int page_is_used(struct mtdoops_context *cxt, int page)
 	return test_bit(page, cxt->oops_page_used);
 }
 
-static void mtdoops_erase_callback(struct erase_info *done)
-{
-	wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
-	wake_up(wait_q);
-}
-
 static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
 {
 	struct mtd_info *mtd = cxt->mtd;
@@ -97,34 +91,21 @@ static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
 	u32 start_page = start_page_offset / record_size;
 	u32 erase_pages = mtd->erasesize / record_size;
 	struct erase_info erase;
-	DECLARE_WAITQUEUE(wait, current);
-	wait_queue_head_t wait_q;
 	int ret;
 	int page;
 
-	init_waitqueue_head(&wait_q);
 	erase.mtd = mtd;
-	erase.callback = mtdoops_erase_callback;
 	erase.addr = offset;
 	erase.len = mtd->erasesize;
-	erase.priv = (u_long)&wait_q;
-
-	set_current_state(TASK_INTERRUPTIBLE);
-	add_wait_queue(&wait_q, &wait);
 
 	ret = mtd_erase(mtd, &erase);
 	if (ret) {
-		set_current_state(TASK_RUNNING);
-		remove_wait_queue(&wait_q, &wait);
 		printk(KERN_WARNING "mtdoops: erase of region [0x%llx, 0x%llx] on \"%s\" failed\n",
 		       (unsigned long long)erase.addr,
 		       (unsigned long long)erase.len, mtddev);
 		return ret;
 	}
 
-	schedule();  /* Wait for erase to finish. */
-	remove_wait_queue(&wait_q, &wait);
-
 	/* Mark pages as unused */
 	for (page = start_page; page < start_page + erase_pages; page++)
 		mark_page_unused(cxt, page);
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 76cd21d1171b..ae1206633d9d 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -222,8 +222,6 @@ void mtd_erase_callback(struct erase_info *instr)
 			instr->fail_addr -= part->offset;
 		instr->addr -= part->offset;
 	}
-	if (instr->callback)
-		instr->callback(instr);
 }
 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 
diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
index 7eb0e1f4f980..d390324d102e 100644
--- a/drivers/mtd/mtdswap.c
+++ b/drivers/mtd/mtdswap.c
@@ -536,18 +536,10 @@ static void mtdswap_store_eb(struct mtdswap_dev *d, struct swap_eb *eb)
 		mtdswap_rb_add(d, eb, MTDSWAP_HIFRAG);
 }
 
-
-static void mtdswap_erase_callback(struct erase_info *done)
-{
-	wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
-	wake_up(wait_q);
-}
-
 static int mtdswap_erase_block(struct mtdswap_dev *d, struct swap_eb *eb)
 {
 	struct mtd_info *mtd = d->mtd;
 	struct erase_info erase;
-	wait_queue_head_t wq;
 	unsigned int retries = 0;
 	int ret;
 
@@ -556,14 +548,11 @@ static int mtdswap_erase_block(struct mtdswap_dev *d, struct swap_eb *eb)
 		d->max_erase_count = eb->erase_count;
 
 retry:
-	init_waitqueue_head(&wq);
 	memset(&erase, 0, sizeof(struct erase_info));
 
 	erase.mtd	= mtd;
-	erase.callback	= mtdswap_erase_callback;
 	erase.addr	= mtdswap_eb_offset(d, eb);
 	erase.len	= mtd->erasesize;
-	erase.priv	= (u_long)&wq;
 
 	ret = mtd_erase(mtd, &erase);
 	if (ret) {
@@ -582,27 +571,6 @@ retry:
 		return -EIO;
 	}
 
-	ret = wait_event_interruptible(wq, erase.state == MTD_ERASE_DONE ||
-					   erase.state == MTD_ERASE_FAILED);
-	if (ret) {
-		dev_err(d->dev, "Interrupted erase block %#llx erasure on %s\n",
-			erase.addr, mtd->name);
-		return -EINTR;
-	}
-
-	if (erase.state == MTD_ERASE_FAILED) {
-		if (retries++ < MTDSWAP_ERASE_RETRIES) {
-			dev_warn(d->dev,
-				"erase of erase block %#llx on %s failed",
-				erase.addr, mtd->name);
-			yield();
-			goto retry;
-		}
-
-		mtdswap_handle_badblock(d, eb);
-		return -EIO;
-	}
-
 	return 0;
 }
 
diff --git a/drivers/mtd/nftlmount.c b/drivers/mtd/nftlmount.c
index 184c8fbfe465..07e122449759 100644
--- a/drivers/mtd/nftlmount.c
+++ b/drivers/mtd/nftlmount.c
@@ -331,9 +331,7 @@ int NFTL_formatblock(struct NFTLrecord *nftl, int block)
 	instr->mtd = nftl->mbd.mtd;
 	instr->addr = block * nftl->EraseSize;
 	instr->len = nftl->EraseSize;
-	mtd_erase(mtd, instr);
-
-	if (instr->state == MTD_ERASE_FAILED) {
+	if (mtd_erase(mtd, instr)) {
 		printk("Error while formatting block %d\n", block);
 		goto fail;
 	}
diff --git a/drivers/mtd/rfd_ftl.c b/drivers/mtd/rfd_ftl.c
index d1cbf26db2c0..4e0b55cd08e2 100644
--- a/drivers/mtd/rfd_ftl.c
+++ b/drivers/mtd/rfd_ftl.c
@@ -266,91 +266,55 @@ static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *b
 	return 0;
 }
 
-static void erase_callback(struct erase_info *erase)
-{
-	struct partition *part;
-	u16 magic;
-	int i, rc;
-	size_t retlen;
-
-	part = (struct partition*)erase->priv;
-
-	i = (u32)erase->addr / part->block_size;
-	if (i >= part->total_blocks || part->blocks[i].offset != erase->addr ||
-	    erase->addr > UINT_MAX) {
-		printk(KERN_ERR PREFIX "erase callback for unknown offset %llx "
-				"on '%s'\n", (unsigned long long)erase->addr, part->mbd.mtd->name);
-		return;
-	}
-
-	if (erase->state != MTD_ERASE_DONE) {
-		printk(KERN_WARNING PREFIX "erase failed at 0x%llx on '%s', "
-				"state %d\n", (unsigned long long)erase->addr,
-				part->mbd.mtd->name, erase->state);
-
-		part->blocks[i].state = BLOCK_FAILED;
-		part->blocks[i].free_sectors = 0;
-		part->blocks[i].used_sectors = 0;
-
-		kfree(erase);
-
-		return;
-	}
-
-	magic = cpu_to_le16(RFD_MAGIC);
-
-	part->blocks[i].state = BLOCK_ERASED;
-	part->blocks[i].free_sectors = part->data_sectors_per_block;
-	part->blocks[i].used_sectors = 0;
-	part->blocks[i].erases++;
-
-	rc = mtd_write(part->mbd.mtd, part->blocks[i].offset, sizeof(magic),
-		       &retlen, (u_char *)&magic);
-
-	if (!rc && retlen != sizeof(magic))
-		rc = -EIO;
-
-	if (rc) {
-		printk(KERN_ERR PREFIX "'%s': unable to write RFD "
-				"header at 0x%lx\n",
-				part->mbd.mtd->name,
-				part->blocks[i].offset);
-		part->blocks[i].state = BLOCK_FAILED;
-	}
-	else
-		part->blocks[i].state = BLOCK_OK;
-
-	kfree(erase);
-}
-
 static int erase_block(struct partition *part, int block)
 {
 	struct erase_info *erase;
-	int rc = -ENOMEM;
+	int rc;
 
 	erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
 	if (!erase)
-		goto err;
+		return -ENOMEM;
 
 	erase->mtd = part->mbd.mtd;
-	erase->callback = erase_callback;
 	erase->addr = part->blocks[block].offset;
 	erase->len = part->block_size;
-	erase->priv = (u_long)part;
 
 	part->blocks[block].state = BLOCK_ERASING;
 	part->blocks[block].free_sectors = 0;
 
 	rc = mtd_erase(part->mbd.mtd, erase);
-
 	if (rc) {
 		printk(KERN_ERR PREFIX "erase of region %llx,%llx on '%s' "
 				"failed\n", (unsigned long long)erase->addr,
 				(unsigned long long)erase->len, part->mbd.mtd->name);
-		kfree(erase);
+		part->blocks[block].state = BLOCK_FAILED;
+		part->blocks[block].free_sectors = 0;
+		part->blocks[block].used_sectors = 0;
+	} else {
+		u16 magic = cpu_to_le16(RFD_MAGIC);
+		size_t retlen;
+
+		part->blocks[block].state = BLOCK_ERASED;
+		part->blocks[block].free_sectors = part->data_sectors_per_block;
+		part->blocks[block].used_sectors = 0;
+		part->blocks[block].erases++;
+
+		rc = mtd_write(part->mbd.mtd, part->blocks[block].offset,
+			       sizeof(magic), &retlen, (u_char *)&magic);
+		if (!rc && retlen != sizeof(magic))
+			rc = -EIO;
+
+		if (rc) {
+			pr_err(PREFIX "'%s': unable to write RFD header at 0x%lx\n",
+			       part->mbd.mtd->name, part->blocks[block].offset);
+			part->blocks[block].state = BLOCK_FAILED;
+		} else {
+			part->blocks[block].state = BLOCK_OK;
+		}
 	}
 
-err:
+	kfree(erase);
+
 	return rc;
 }
 
diff --git a/drivers/mtd/sm_ftl.c b/drivers/mtd/sm_ftl.c
index 4237c7cebf02..c11156f9d96f 100644
--- a/drivers/mtd/sm_ftl.c
+++ b/drivers/mtd/sm_ftl.c
@@ -461,10 +461,8 @@ static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
 	struct erase_info erase;
 
 	erase.mtd = mtd;
-	erase.callback = sm_erase_callback;
 	erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
 	erase.len = ftl->block_size;
-	erase.priv = (u_long)ftl;
 
 	if (ftl->unstable)
 		return -EIO;
@@ -482,15 +480,6 @@ static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
 		goto error;
 	}
 
-	if (erase.state == MTD_ERASE_PENDING)
-		wait_for_completion(&ftl->erase_completion);
-
-	if (erase.state != MTD_ERASE_DONE) {
-		sm_printk("erase of block %d in zone %d failed after wait",
-			block, zone_num);
-		goto error;
-	}
-
 	if (put_free)
 		kfifo_in(&zone->free_sectors,
 			(const unsigned char *)&block, sizeof(block));
@@ -501,12 +490,6 @@ error:
 	return -EIO;
 }
 
-static void sm_erase_callback(struct erase_info *self)
-{
-	struct sm_ftl *ftl = (struct sm_ftl *)self->priv;
-	complete(&ftl->erase_completion);
-}
-
 /* Thoroughly test that block is valid. */
 static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
 {
@@ -1141,7 +1124,6 @@ static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
 	mutex_init(&ftl->mutex);
 	timer_setup(&ftl->timer, sm_cache_flush_timer, 0);
 	INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
-	init_completion(&ftl->erase_completion);
 
 	/* Read media information */
 	if (sm_get_media_info(ftl, mtd)) {
diff --git a/drivers/mtd/sm_ftl.h b/drivers/mtd/sm_ftl.h
index 43bb7300785b..0a46d75cdc6a 100644
--- a/drivers/mtd/sm_ftl.h
+++ b/drivers/mtd/sm_ftl.h
@@ -53,9 +53,6 @@ struct sm_ftl {
 	struct work_struct flush_work;
 	struct timer_list timer;
 
-	/* Async erase stuff */
-	struct completion erase_completion;
-
 	/* Geometry stuff */
 	int heads;
 	int sectors;
@@ -86,7 +83,6 @@ struct chs_entry {
 		printk(KERN_DEBUG "sm_ftl" ": " format "\n", ## __VA_ARGS__)
 
 
-static void sm_erase_callback(struct erase_info *self);
 static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
 								int put_free);
 static void sm_mark_block_bad(struct sm_ftl *ftl, int zone_num, int block);
diff --git a/drivers/mtd/tests/mtd_test.c b/drivers/mtd/tests/mtd_test.c
index 3d0b8b5c1a53..0ac625e8f798 100644
--- a/drivers/mtd/tests/mtd_test.c
+++ b/drivers/mtd/tests/mtd_test.c
@@ -24,10 +24,6 @@ int mtdtest_erase_eraseblock(struct mtd_info *mtd, unsigned int ebnum)
 		return err;
 	}
 
-	if (ei.state == MTD_ERASE_FAILED) {
-		pr_info("some erase error occurred at EB %d\n", ebnum);
-		return -EIO;
-	}
 	return 0;
 }
 
diff --git a/drivers/mtd/tests/speedtest.c b/drivers/mtd/tests/speedtest.c
index 0b89418a0888..f8e5dc11f943 100644
--- a/drivers/mtd/tests/speedtest.c
+++ b/drivers/mtd/tests/speedtest.c
@@ -70,12 +70,6 @@ static int multiblock_erase(int ebnum, int blocks)
 		return err;
 	}
 
-	if (ei.state == MTD_ERASE_FAILED) {
-		pr_err("some erase error occurred at EB %d,"
-		       "blocks %d\n", ebnum, blocks);
-		return -EIO;
-	}
-
 	return 0;
 }
 
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index 8290432017ce..8843d26837b2 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 +331,11 @@ 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 +350,6 @@ 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;