mtd: introduce mtd_erase interface

This patch is part of a patch-set which changes the MTD interface
from 'mtd->func()' form to 'mtd_func()' form. We need this because
we want to add common code to to all drivers in the mtd core level,
which is impossible with the current interface when MTD clients
call driver functions like 'read()' or 'write()' directly.

At this point we just introduce a new inline wrapper function, but
later some of them are expected to gain more code. E.g., the input
parameters check should be moved to the wrappers rather than be
duplicated at many drivers.

This particular patch introduced the 'mtd_erase()' interface. The
following patches add all the other interfaces one by one.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c
index c7382bb..a982889 100644
--- a/drivers/mtd/ftl.c
+++ b/drivers/mtd/ftl.c
@@ -355,7 +355,7 @@
     erase->len = 1 << part->header.EraseUnitSize;
     erase->priv = (u_long)part;
 
-    ret = part->mbd.mtd->erase(part->mbd.mtd, erase);
+    ret = mtd_erase(part->mbd.mtd, erase);
 
     if (!ret)
 	    xfer->EraseCount++;
diff --git a/drivers/mtd/inftlmount.c b/drivers/mtd/inftlmount.c
index 2ff601f..0d946f1 100644
--- a/drivers/mtd/inftlmount.c
+++ b/drivers/mtd/inftlmount.c
@@ -220,7 +220,7 @@
 				 */
 				instr->addr = ip->Reserved0 * inftl->EraseSize;
 				instr->len = inftl->EraseSize;
-				mtd->erase(mtd, instr);
+				mtd_erase(mtd, instr);
 			}
 			if ((ip->lastUnit - ip->firstUnit + 1) < ip->virtualUnits) {
 				printk(KERN_WARNING "INFTL: Media Header "
@@ -393,7 +393,7 @@
 	   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);
+		mtd_erase(inftl->mbd.mtd, instr);
 
 		if (instr->state == MTD_ERASE_FAILED) {
 			printk(KERN_WARNING "INFTL: error while formatting block %d\n",
diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
index 7c1dc90..9b01cb0 100644
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -85,7 +85,7 @@
 	set_current_state(TASK_INTERRUPTIBLE);
 	add_wait_queue(&wait_q, &wait);
 
-	ret = mtd->erase(mtd, &erase);
+	ret = mtd_erase(mtd, &erase);
 	if (ret) {
 		set_current_state(TASK_RUNNING);
 		remove_wait_queue(&wait_q, &wait);
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 00423cc..41d64ff 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -731,7 +731,7 @@
 			  wq_head is no longer there when the
 			  callback routine tries to wake us up.
 			*/
-			ret = mtd->erase(mtd, erase);
+			ret = mtd_erase(mtd, erase);
 			if (!ret) {
 				set_current_state(TASK_UNINTERRUPTIBLE);
 				add_wait_queue(&waitq, &wait);
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 6df4d4d..76123bd 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -379,7 +379,7 @@
 	 * FIXME: Allow INTERRUPTIBLE. Which means
 	 * not having the wait_queue head on the stack.
 	 */
-	err = mtd->erase(mtd, erase);
+	err = mtd_erase(mtd, erase);
 	if (!err) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		add_wait_queue(&waitq, &wait);
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index f3cdce9..9b2d863 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -112,7 +112,7 @@
 	set_current_state(TASK_INTERRUPTIBLE);
 	add_wait_queue(&wait_q, &wait);
 
-	ret = mtd->erase(mtd, &erase);
+	ret = mtd_erase(mtd, &erase);
 	if (ret) {
 		set_current_state(TASK_RUNNING);
 		remove_wait_queue(&wait_q, &wait);
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index a0bd2de..d318fee 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -257,7 +257,7 @@
 	if (instr->addr >= mtd->size)
 		return -EINVAL;
 	instr->addr += part->offset;
-	ret = part->master->erase(part->master, instr);
+	ret = mtd_erase(part->master, instr);
 	if (ret) {
 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 			instr->fail_addr -= part->offset;
diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
index bd9590c..4e12875 100644
--- a/drivers/mtd/mtdswap.c
+++ b/drivers/mtd/mtdswap.c
@@ -567,7 +567,7 @@
 	erase.len	= mtd->erasesize;
 	erase.priv	= (u_long)&wq;
 
-	ret = mtd->erase(mtd, &erase);
+	ret = mtd_erase(mtd, &erase);
 	if (ret) {
 		if (retries++ < MTDSWAP_ERASE_RETRIES) {
 			dev_warn(d->dev,
diff --git a/drivers/mtd/nftlmount.c b/drivers/mtd/nftlmount.c
index ac40925..9164a56 100644
--- a/drivers/mtd/nftlmount.c
+++ b/drivers/mtd/nftlmount.c
@@ -326,7 +326,7 @@
 	instr->mtd = nftl->mbd.mtd;
 	instr->addr = block * nftl->EraseSize;
 	instr->len = nftl->EraseSize;
-	mtd->erase(mtd, instr);
+	mtd_erase(mtd, instr);
 
 	if (instr->state == MTD_ERASE_FAILED) {
 		printk("Error while formatting block %d\n", block);
diff --git a/drivers/mtd/rfd_ftl.c b/drivers/mtd/rfd_ftl.c
index 73ae217..39de872 100644
--- a/drivers/mtd/rfd_ftl.c
+++ b/drivers/mtd/rfd_ftl.c
@@ -342,7 +342,7 @@
 	part->blocks[block].state = BLOCK_ERASING;
 	part->blocks[block].free_sectors = 0;
 
-	rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
+	rc = mtd_erase(part->mbd.mtd, erase);
 
 	if (rc) {
 		printk(KERN_ERR PREFIX "erase of region %llx,%llx on '%s' "
diff --git a/drivers/mtd/sm_ftl.c b/drivers/mtd/sm_ftl.c
index 1c9f307..2f1acb1 100644
--- a/drivers/mtd/sm_ftl.c
+++ b/drivers/mtd/sm_ftl.c
@@ -479,7 +479,7 @@
 		return -EIO;
 	}
 
-	if (mtd->erase(mtd, &erase)) {
+	if (mtd_erase(mtd, &erase)) {
 		sm_printk("erase of block %d in zone %d failed",
 							block, zone_num);
 		goto error;
diff --git a/drivers/mtd/tests/mtd_oobtest.c b/drivers/mtd/tests/mtd_oobtest.c
index 933f7e5..7d52854 100644
--- a/drivers/mtd/tests/mtd_oobtest.c
+++ b/drivers/mtd/tests/mtd_oobtest.c
@@ -78,7 +78,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
diff --git a/drivers/mtd/tests/mtd_pagetest.c b/drivers/mtd/tests/mtd_pagetest.c
index afafb69..271819f 100644
--- a/drivers/mtd/tests/mtd_pagetest.c
+++ b/drivers/mtd/tests/mtd_pagetest.c
@@ -77,7 +77,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
diff --git a/drivers/mtd/tests/mtd_speedtest.c b/drivers/mtd/tests/mtd_speedtest.c
index 493b367..f67a65e 100644
--- a/drivers/mtd/tests/mtd_speedtest.c
+++ b/drivers/mtd/tests/mtd_speedtest.c
@@ -79,7 +79,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
@@ -105,7 +105,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize * blocks;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d, blocks %d\n",
 		       err, ebnum, blocks);
diff --git a/drivers/mtd/tests/mtd_stresstest.c b/drivers/mtd/tests/mtd_stresstest.c
index 811642f..a204a9f 100644
--- a/drivers/mtd/tests/mtd_stresstest.c
+++ b/drivers/mtd/tests/mtd_stresstest.c
@@ -112,7 +112,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (unlikely(err)) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
diff --git a/drivers/mtd/tests/mtd_subpagetest.c b/drivers/mtd/tests/mtd_subpagetest.c
index 1a05bfa..16d0c05 100644
--- a/drivers/mtd/tests/mtd_subpagetest.c
+++ b/drivers/mtd/tests/mtd_subpagetest.c
@@ -80,7 +80,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
diff --git a/drivers/mtd/tests/mtd_torturetest.c b/drivers/mtd/tests/mtd_torturetest.c
index 03ab649..102c79b 100644
--- a/drivers/mtd/tests/mtd_torturetest.c
+++ b/drivers/mtd/tests/mtd_torturetest.c
@@ -105,7 +105,7 @@
 	ei.addr = addr;
 	ei.len  = mtd->erasesize;
 
-	err = mtd->erase(mtd, &ei);
+	err = mtd_erase(mtd, &ei);
 	if (err) {
 		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
 		return err;
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index f20b6f2..b6c8959 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -361,7 +361,7 @@
 	ei.callback = erase_callback;
 	ei.priv     = (unsigned long)&wq;
 
-	err = ubi->mtd->erase(ubi->mtd, &ei);
+	err = mtd_erase(ubi->mtd, &ei);
 	if (err) {
 		if (retries++ < UBI_IO_RETRIES) {
 			dbg_io("error %d while erasing PEB %d, retry",