mtd: Add mtdswap block driver

Add a driver for allowing an mtd device to be used as a block device for
swapping. The block device is volatile, and the mapping of swapped pages
is not stored on flash.

Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Tested-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 23088b3372d0..5fe01d556657 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -325,6 +325,24 @@ config MTD_OOPS
           To use, add console=ttyMTDx to the kernel command line,
           where x is the MTD device number to use.
 
+config MTD_SWAP
+        tristate "Swap on MTD device support"
+        depends on MTD && SWAP
+        select MTD_BLKDEVS
+        help
+          Provides volatile block device driver on top of mtd partition
+          suitable for swapping.  The mapping of written blocks is not saved.
+          The driver provides wear leveling by storing erase counter into the
+          OOB.
+
+config MTD_SWAP_STRICT
+       bool "Strict erase error handling"
+       depends on MTD_SWAP
+       help
+         Enables strict tolerance on failed erasures, marking erase blocks bad
+         right after the first failed operation. With non-strict mode the
+         erase operation is retried.
+
 source "drivers/mtd/chips/Kconfig"
 
 source "drivers/mtd/maps/Kconfig"