mmc: fix mmc_app_send_scr() for dma transfer

This patch is based on the commit "af51715079e7fb6b290e1881d63d815dc4de5011":

   * Bugfix to that mmc_send_cxd_data() code:  dma-to-stack is
     unsafe/nonportable, so kmalloc a bounce buffer instead.

The driver may invalidate the mmc_card->csd when host driver uses dma.
So this subroutine also needs a kmalloc buffer.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Yoshihiro Shimoda 2011-03-25 15:06:19 +09:00 committed by Chris Ball
parent 58ac8177ce
commit 4f665cb614

View File

@ -9,6 +9,7 @@
* your option) any later version.
*/
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/scatterlist.h>
@ -252,6 +253,7 @@ int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
struct mmc_command cmd;
struct mmc_data data;
struct scatterlist sg;
void *data_buf;
BUG_ON(!card);
BUG_ON(!card->host);
@ -263,6 +265,13 @@ int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
if (err)
return err;
/* dma onto stack is unsafe/nonportable, but callers to this
* routine normally provide temporary on-stack buffers ...
*/
data_buf = kmalloc(sizeof(card->raw_scr), GFP_KERNEL);
if (data_buf == NULL)
return -ENOMEM;
memset(&mrq, 0, sizeof(struct mmc_request));
memset(&cmd, 0, sizeof(struct mmc_command));
memset(&data, 0, sizeof(struct mmc_data));
@ -280,12 +289,15 @@ int mmc_app_send_scr(struct mmc_card *card, u32 *scr)
data.sg = &sg;
data.sg_len = 1;
sg_init_one(&sg, scr, 8);
sg_init_one(&sg, data_buf, 8);
mmc_set_data_timeout(&data, card);
mmc_wait_for_req(card->host, &mrq);
memcpy(scr, data_buf, sizeof(card->raw_scr));
kfree(data_buf);
if (cmd.error)
return cmd.error;
if (data.error)