[PATCH] Fix Oops with Atmel SPI

[Anders Larsen]

Tweak MTD's cache allocation to make it work with the atmel DMA'ed SPI.
Substitute kmalloc for vmalloc so the cache buffer is mappable as per
the Atmel SPI driver's requirements, otherwise an Oops would occur.

The original patch by Ian McDonnell <ian at brightstareng.com> was found here:
http://lists.infradead.org/pipermail/linux-mtd/2007-December/020184.html

Signed-off-by: Anders Larsen <al at alarsen.net>
Cc: Ian McDonnell <ian at brightstareng.com>
Cc: David Woodhouse <dwmw2 at infradead.org>
Cc: Matthias Kaehlcke <matthias at kaehlcke.net>
Cc: Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
Cc: Nicolas Pitre <nico at fluxnic.net>
---
 drivers/mtd/mtdblock.c |    8 ++++++++
 1 file changed, 8 insertions(+)

Index: b/drivers/mtd/mtdblock.c
===================================================================
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -253,7 +253,11 @@ static int mtdblock_writesect(struct mtd
 {
 	struct mtdblk_dev *mtdblk = mtdblks[dev->devnum];
 	if (unlikely(!mtdblk->cache_data && mtdblk->cache_size)) {
+#ifdef CONFIG_SPI_ATMEL
+		mtdblk->cache_data = kmalloc(mtdblk->mtd->erasesize, GFP_KERNEL);
+#else
 		mtdblk->cache_data = vmalloc(mtdblk->mtd->erasesize);
+#endif
 		if (!mtdblk->cache_data)
 			return -EINTR;
 		/* -EINTR is not really correct, but it is the best match
@@ -322,7 +326,11 @@ static int mtdblock_release(struct mtd_b
 		mtdblks[dev] = NULL;
 		if (mtdblk->mtd->sync)
 			mtdblk->mtd->sync(mtdblk->mtd);
+#ifdef CONFIG_SPI_ATMEL
+		kfree(mtdblk->cache_data);
+#else
 		vfree(mtdblk->cache_data);
+#endif
 		kfree(mtdblk);
 	}