[PATCH] mtd: cfi_cmdset_0002: dynamically determine the max sectors

From: Chris Packham
Date: Tue May 21 2019 - 20:09:33 EST


Because PPB unlocking unlocks the whole chip cfi_ppb_unlock() needs to
remember the locked status for each sector so it can re-lock the
unaddressed sectors. Dynamically calculate the maximum number of sectors
rather than using a hardcoded value that is too small for larger chips.

Tested with Spansion S29GL01GS11TFI flash device.

Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/chips/cfi_cmdset_0002.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index c8fa5906bdf9..a1a7d334aa82 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -2533,8 +2533,6 @@ struct ppb_lock {
int locked;
};

-#define MAX_SECTORS 512
-
#define DO_XXLOCK_ONEBLOCK_LOCK ((void *)1)
#define DO_XXLOCK_ONEBLOCK_UNLOCK ((void *)2)
#define DO_XXLOCK_ONEBLOCK_GETLOCK ((void *)3)
@@ -2633,6 +2631,7 @@ static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
int i;
int sectors;
int ret;
+ int max_sectors;

/*
* PPB unlocking always unlocks all sectors of the flash chip.
@@ -2640,7 +2639,11 @@ static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
* first check the locking status of all sectors and save
* it for future use.
*/
- sect = kcalloc(MAX_SECTORS, sizeof(struct ppb_lock), GFP_KERNEL);
+ max_sectors = 0;
+ for (i = 0; i < mtd->numeraseregions; i++)
+ max_sectors += regions[i].numblocks;
+
+ sect = kcalloc(max_sectors, sizeof(struct ppb_lock), GFP_KERNEL);
if (!sect)
return -ENOMEM;

@@ -2689,9 +2692,9 @@ static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
}

sectors++;
- if (sectors >= MAX_SECTORS) {
+ if (sectors >= max_sectors) {
printk(KERN_ERR "Only %d sectors for PPB locking supported!\n",
- MAX_SECTORS);
+ max_sectors);
kfree(sect);
return -EINVAL;
}
--
2.21.0