mtd: cfi: cmdset_0001: Do not allow read/write to suspend erase block.

Currently it is possible to read and/or write to suspend EB's.
Writing /dev/mtdX or /dev/mtdblockX from several processes may
break the flash state machine.

Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
This commit is contained in:
Joakim Tjernlund 2018-03-01 14:39:39 +01:00 committed by Boris Brezillon
parent 47016b341f
commit 6510bbc88e
2 changed files with 12 additions and 5 deletions

View File

@ -831,21 +831,25 @@ static int chip_ready (struct map_info *map, struct flchip *chip, unsigned long
(mode == FL_WRITING && (cfip->SuspendCmdSupport & 1))))
goto sleep;
/* Do not allow suspend iff read/write to EB address */
if ((adr & chip->in_progress_block_mask) ==
chip->in_progress_block_addr)
goto sleep;
/* Erase suspend */
map_write(map, CMD(0xB0), adr);
map_write(map, CMD(0xB0), chip->in_progress_block_addr);
/* If the flash has finished erasing, then 'erase suspend'
* appears to make some (28F320) flash devices switch to
* 'read' mode. Make sure that we switch to 'read status'
* mode so we get the right data. --rmk
*/
map_write(map, CMD(0x70), adr);
map_write(map, CMD(0x70), chip->in_progress_block_addr);
chip->oldstate = FL_ERASING;
chip->state = FL_ERASE_SUSPENDING;
chip->erase_suspended = 1;
for (;;) {
status = map_read(map, adr);
status = map_read(map, chip->in_progress_block_addr);
if (map_word_andequal(map, status, status_OK, status_OK))
break;
@ -1041,8 +1045,8 @@ static void put_chip(struct map_info *map, struct flchip *chip, unsigned long ad
sending the 0x70 (Read Status) command to an erasing
chip and expecting it to be ignored, that's what we
do. */
map_write(map, CMD(0xd0), adr);
map_write(map, CMD(0x70), adr);
map_write(map, CMD(0xd0), chip->in_progress_block_addr);
map_write(map, CMD(0x70), chip->in_progress_block_addr);
chip->oldstate = FL_READY;
chip->state = FL_ERASING;
break;
@ -1933,6 +1937,8 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
map_write(map, CMD(0xD0), adr);
chip->state = FL_ERASING;
chip->erase_suspended = 0;
chip->in_progress_block_addr = adr;
chip->in_progress_block_mask = ~(len - 1);
ret = INVAL_CACHE_AND_WAIT(map, chip, adr,
adr, len,

View File

@ -85,6 +85,7 @@ struct flchip {
unsigned int write_suspended:1;
unsigned int erase_suspended:1;
unsigned long in_progress_block_addr;
unsigned long in_progress_block_mask;
struct mutex mutex;
wait_queue_head_t wq; /* Wait on here when we're waiting for the chip