mtd: Collect bad block count for ecc stats lazily.
Normally bad block counts for ECC stats are collected during boot time.
This can be done lazily when the ECCGETSTATS ioctl is invoked on the
partition. This can significantly decrease boot time, depending on the
size of the partition. Also rescanning on every ioctl invocation helps
in having the latest bad block count rather than depending on the count
that is collected during boot.
Change-Id: I43d7a769a1d4ef769823d0b5bbe132adb474f892
Signed-off-by: Murali Palnati <palnatim@codeaurora.org>
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 4be8373..167efd9 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -318,6 +318,17 @@
The driver provides wear leveling by storing erase counter into the
OOB.
+config MTD_LAZYECCSTATS
+ bool "MTD Lazy ECC Stats collection support"
+ default y
+ help
+ Normally bad block counts for ECC stats are collected at boot time.
+ This option delays the badblock stats collection until ECCGETSTATS
+ ioctl is invoked on the partition.
+
+ This can significantly decrease boot times depending on the size of
+ the partition. If unsure, say 'N'.
+
source "drivers/mtd/chips/Kconfig"
source "drivers/mtd/maps/Kconfig"
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index f1af222..ed9468c 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -34,6 +34,7 @@
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
#include <asm/uaccess.h>
@@ -904,6 +905,9 @@
case ECCGETSTATS:
{
+#ifdef CONFIG_MTD_LAZYECCSTATS
+ part_fill_badblockstats(mtd);
+#endif
if (copy_to_user(argp, &mtd->ecc_stats,
sizeof(struct mtd_ecc_stats)))
return -EFAULT;
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 630be3e..4c75f32 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -353,6 +353,21 @@
kfree(p);
}
+void part_fill_badblockstats(struct mtd_info *mtd)
+{
+ struct mtd_part *part = PART(mtd);
+ if (part->master->block_isbad) {
+ uint64_t offs = 0;
+ mtd->ecc_stats.badblocks = 0;
+ while (offs < mtd->size) {
+ if (part->master->block_isbad(part->master,
+ offs + part->offset))
+ mtd->ecc_stats.badblocks++;
+ offs += mtd->erasesize;
+ }
+ }
+}
+
/*
* This function unregisters and destroy all slave MTD objects which are
* attached to the given master MTD object.
@@ -542,16 +557,10 @@
}
slave->mtd.ecclayout = master->ecclayout;
- if (master->block_isbad) {
- uint64_t offs = 0;
- while (offs < slave->mtd.size) {
- if (master->block_isbad(master,
- offs + slave->offset))
- slave->mtd.ecc_stats.badblocks++;
- offs += slave->mtd.erasesize;
- }
- }
+#ifndef CONFIG_MTD_LAZYECCSTATS
+ part_fill_badblockstats(&(slave->mtd));
+#endif
out_register:
return slave;