Commit b32843b7 authored by Brian Norris's avatar Brian Norris Committed by David Woodhouse
Browse files

mtd: nand: hide in-memory BBT implementation details 



nand_base.c shouldn't have to know the implementation details of
nand_bbt's in-memory BBT. Specifically, nand_base shouldn't perform the
bit masking and shifting to isolate a BBT entry.

Instead, just move some of the BBT code into a new nand_markbad_bbt()
interface. This interface allows external users (i.e., nand_base) to
mark a single block as bad in the BBT. Then nand_bbt will take care of
modifying the in-memory BBT and updating the flash-based BBT (if
applicable).

Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent 5a0edb25

drivers/mtd/nand/nand_base.c

+11 −21
Original line number Diff line number Diff line
@@ -374,22 +374,20 @@ static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs) 
 * block table(s) and/or marker(s)). We only allow the hardware driver to

 * specify how to write bad block markers to OOB (chip->block_markbad).

 *

 * We try operations in the following order, according to our bbt_options

 * (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):

 * We try operations in the following order:

 *  (1) erase the affected block, to allow OOB marker to be written cleanly

 *  (2) update in-memory BBT

 *  (3) write bad block marker to OOB area of affected block

 *  (4) update flash-based BBT

 * Note that we retain the first error encountered in (3) or (4), finish the

 *  (2) write bad block marker to OOB area of affected block (unless flag

 *      NAND_BBT_NO_OOB_BBM is present)

 *  (3) update the BBT

 * Note that we retain the first error encountered in (2) or (3), finish the

 * procedures, and dump the error in the end.

*/

static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)

{

	struct nand_chip *chip = mtd->priv;

	int block, res, ret = 0;

	int write_oob = !(chip->bbt_options & NAND_BBT_NO_OOB_BBM);

	int res, ret = 0;



	if (write_oob) {

	if (!(chip->bbt_options & NAND_BBT_NO_OOB_BBM)) {

		struct erase_info einfo;



		/* Attempt erase before marking OOB */
@@ -398,24 +396,16 @@ static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs) 
		einfo.addr = ofs;

		einfo.len = 1 << chip->phys_erase_shift;

		nand_erase_nand(mtd, &einfo, 0);

	}



	/* Get block number */

	block = (int)(ofs >> chip->bbt_erase_shift);

	/* Mark block bad in memory-based BBT */

	if (chip->bbt)

		chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);



		/* Write bad block marker to OOB */

	if (write_oob) {

		nand_get_device(mtd, FL_WRITING);

		ret = chip->block_markbad(mtd, ofs);

		nand_release_device(mtd);

	}



	/* Update flash-based bad block table */

	if (chip->bbt_options & NAND_BBT_USE_FLASH) {

		res = nand_update_bbt(mtd, ofs);

	/* Mark block bad in BBT */

	if (chip->bbt) {

		res = nand_markbad_bbt(mtd, ofs);

		if (!ret)

			ret = res;

	}

drivers/mtd/nand/nand_bbt.c

+26 −2
Original line number Diff line number Diff line
@@ -79,6 +79,8 @@ 
#define BBT_ENTRY_MASK		0x03

#define BBT_ENTRY_SHIFT		2



static int nand_update_bbt(struct mtd_info *mtd, loff_t offs);



static inline uint8_t bbt_get_entry(struct nand_chip *chip, int block)

{

	uint8_t entry = chip->bbt[block >> BBT_ENTRY_SHIFT];
@@ -1194,13 +1196,13 @@ int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd) 
}



/**

 * nand_update_bbt - [NAND Interface] update bad block table(s)

 * nand_update_bbt - update bad block table(s)

 * @mtd: MTD device structure

 * @offs: the offset of the newly marked block

 *

 * The function updates the bad block table(s).

 */

int nand_update_bbt(struct mtd_info *mtd, loff_t offs)

static int nand_update_bbt(struct mtd_info *mtd, loff_t offs)

{

	struct nand_chip *this = mtd->priv;

	int len, res = 0;
@@ -1390,5 +1392,27 @@ int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt) 
	return 1;

}



/**

 * nand_markbad_bbt - [NAND Interface] Mark a block bad in the BBT

 * @mtd: MTD device structure

 * @offs: offset of the bad block

 */

int nand_markbad_bbt(struct mtd_info *mtd, loff_t offs)

{

	struct nand_chip *this = mtd->priv;

	int block, ret = 0;



	block = (int)(offs >> this->bbt_erase_shift);



	/* Mark bad block in memory */

	bbt_mark_entry(this, block, BBT_BLOCK_WORN);



	/* Update flash-based bad block table */

	if (this->bbt_options & NAND_BBT_USE_FLASH)

		ret = nand_update_bbt(mtd, offs);



	return ret;

}



EXPORT_SYMBOL(nand_scan_bbt);

EXPORT_SYMBOL(nand_default_bbt);

include/linux/mtd/nand.h

+1 −1
Original line number Diff line number Diff line
@@ -628,8 +628,8 @@ extern struct nand_flash_dev nand_flash_ids[]; 
extern struct nand_manufacturers nand_manuf_ids[];



extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);

extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);

extern int nand_default_bbt(struct mtd_info *mtd);

extern int nand_markbad_bbt(struct mtd_info *mtd, loff_t offs);

extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);

extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,

			   int allowbbt);

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