From 4f665cb614b8a258b507cc47753dd3f7dd45aac6 Mon Sep 17 00:00:00 2001 From: Yoshihiro Shimoda Date: Fri, 25 Mar 2011 15:06:19 +0900 Subject: [PATCH] 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 Signed-off-by: Chris Ball --- drivers/mmc/core/sd_ops.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/sd_ops.c b/drivers/mmc/core/sd_ops.c index 797cdb5..76af349 100644 --- a/drivers/mmc/core/sd_ops.c +++ b/drivers/mmc/core/sd_ops.c @@ -9,6 +9,7 @@ * your option) any later version. */ +#include #include #include @@ -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) -- 2.7.4