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>

drivers/mtd/ftl.c

@@ -355,7 +355,7 @@ static int erase_xfer(partition_t *part,
     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++;

drivers/mtd/inftlmount.c

@@ -220,7 +220,7 @@ static int find_boot_record(struct INFTLrecord *inftl)
 				 */
 				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 @@ 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);
+		mtd_erase(inftl->mbd.mtd, instr);
 
 		if (instr->state == MTD_ERASE_FAILED) {
 			printk(KERN_WARNING "INFTL: error while formatting block %d\n",

drivers/mtd/mtdblock.c

@@ -85,7 +85,7 @@ static int erase_write (struct mtd_info *mtd, unsigned long pos,
 	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);

drivers/mtd/mtdchar.c

@@ -731,7 +731,7 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 			  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);

drivers/mtd/mtdconcat.c

@@ -379,7 +379,7 @@ static int concat_dev_erase(struct mtd_info *mtd, struct erase_info *erase)
 	 * 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);

drivers/mtd/mtdoops.c

@@ -112,7 +112,7 @@ static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
 	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);

drivers/mtd/mtdpart.c

@@ -257,7 +257,7 @@ static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 	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;

drivers/mtd/mtdswap.c

@@ -567,7 +567,7 @@ retry:
 	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,

drivers/mtd/nftlmount.c

@@ -326,7 +326,7 @@ 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);
+	mtd_erase(mtd, instr);
 
 	if (instr->state == MTD_ERASE_FAILED) {
 		printk("Error while formatting block %d\n", block);

drivers/mtd/rfd_ftl.c

@@ -342,7 +342,7 @@ static int erase_block(struct partition *part, int block)
 	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' "

drivers/mtd/sm_ftl.c

@@ -479,7 +479,7 @@ static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
 		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;

drivers/mtd/tests/mtd_oobtest.c

@@ -78,7 +78,7 @@ static int erase_eraseblock(int ebnum)
 	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;

drivers/mtd/tests/mtd_pagetest.c

@@ -77,7 +77,7 @@ static int erase_eraseblock(int ebnum)
 	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;

drivers/mtd/tests/mtd_speedtest.c

@@ -79,7 +79,7 @@ static int erase_eraseblock(int ebnum)
 	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 @@ static int multiblock_erase(int ebnum, int blocks)
 	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);

drivers/mtd/tests/mtd_stresstest.c

@@ -112,7 +112,7 @@ static int erase_eraseblock(int ebnum)
 	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;

drivers/mtd/tests/mtd_subpagetest.c

@@ -80,7 +80,7 @@ static int erase_eraseblock(int ebnum)
 	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;

drivers/mtd/tests/mtd_torturetest.c

@@ -105,7 +105,7 @@ static inline int erase_eraseblock(int ebnum)
 	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;

drivers/mtd/ubi/io.c

@@ -361,7 +361,7 @@ retry:
 	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",

drivers/staging/spectra/lld_mtd.c

@@ -188,7 +188,7 @@ u16 mtd_Erase_Block(u32 block_add)
 	erase.len = spectra_mtd->erasesize;
 	erase.priv = (unsigned long)∁
 
-	ret = spectra_mtd->erase(spectra_mtd, &erase);
+	ret = mtd_erase(spectra_mtd, &erase);
 	if (!ret) {
 		wait_for_completion(&comp);
 		if (erase.state != MTD_ERASE_DONE)

fs/jffs2/erase.c

@@ -74,7 +74,7 @@ static void jffs2_erase_block(struct jffs2_sb_info *c,
 	((struct erase_priv_struct *)instr->priv)->jeb = jeb;
 	((struct erase_priv_struct *)instr->priv)->c = c;
 
-	ret = c->mtd->erase(c->mtd, instr);
+	ret = mtd_erase(c->mtd, instr);
 	if (!ret)
 		return;
 

fs/logfs/dev_mtd.c

@@ -105,7 +105,7 @@ static int logfs_mtd_erase(struct super_block *sb, loff_t ofs, size_t len,
 	ei.len = len;
 	ei.callback = logfs_erase_callback;
 	ei.priv = (long)&complete;
-	ret = mtd->erase(mtd, &ei);
+	ret = mtd_erase(mtd, &ei);
 	if (ret)
 		return -EIO;
 

include/linux/mtd/mtd.h

@@ -171,11 +171,8 @@ struct mtd_info {
 	struct mtd_erase_region_info *eraseregions;
 
 	/*
-	 * 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.
+	 * Do not call via these pointers, use corresponding mtd_*()
+	 * wrappers instead.
 	 */
 	int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 
@@ -274,6 +271,18 @@ struct mtd_info {
 	void (*put_device) (struct mtd_info *mtd);
 };
 
+/*
+ * 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.
+ */
+static inline int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+	return mtd->erase(mtd, instr);
+}
+
 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 {
 	return dev ? dev_get_drvdata(dev) : NULL;