[JFFS2] Add support for write-buffer verification.

We've seen some evil corruption issues, where the corruption seems to be
introduced after the JFFS2 crc32 is calculated but before the NAND
controller calculates the ECC. So it's in RAM or in the PCI DMA
transfer; not on the flash. Attempt to catch it earlier by (optionally)
reading back from the flash immediately after writing it.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index e9c5b81dd665..e19423a2aa7d 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -1228,6 +1228,14 @@ config JFFS2_FS_WRITEBUFFER
             - NOR flash with transparent ECC
             - DataFlash
 
+config JFFS2_FS_WBUF_VERIFY
+        bool "Verify JFFS2 write-buffer reads"
+        depends on JFFS2_FS_WRITEBUFFER
+        default n
+        help
+          This causes JFFS2 to read back every page written through the
+          write-buffer, and check for errors.
+
 config JFFS2_SUMMARY
         bool "JFFS2 summary support (EXPERIMENTAL)"
         depends on JFFS2_FS && EXPERIMENTAL