[PATCH 4.2 109/134] mmc: sdhci: fix dma memory leak in sdhci_pre_req()

Greg Kroah-Hartman
2015-09-26T21:55:13Z

From: Haibo Chen <haibo.chen@freescale.com>

commit d31911b9374a76560d2c8ea4aa6ce5781621e81d upstream.

Currently one mrq->data maybe execute dma_map_sg() twice
when mmc subsystem prepare over one new request, and the
following log show up:
sdhci[sdhci_pre_dma_transfer] invalid cookie: 24, next-cookie 25

In this condition, mrq->date map a dma-memory(1) in sdhci_pre_req
for the first time, and map another dma-memory(2) in sdhci_prepare_data
for the second time. But driver only unmap the dma-memory(2), and
dma-memory(1) never unmapped, which cause the dma memory leak issue.

This patch use another method to map the dma memory for the mrq->data
which can fix this dma memory leak issue.

Fixes: 348487cb28e6 ("mmc: sdhci: use pipeline mmc requests to improve performance")
Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Haibo Chen <haibo.chen@freescale.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/mmc/host/sdhci.c | 67 +++++++++++++++++------------------------------
drivers/mmc/host/sdhci.h | 8 ++---
2 files changed, 29 insertions(+), 46 deletions(-)

--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -54,8 +54,7 @@ static void sdhci_finish_command(struct
static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode);
static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);
static int sdhci_pre_dma_transfer(struct sdhci_host *host,
- struct mmc_data *data,
- struct sdhci_host_next *next);
+ struct mmc_data *data);
static int sdhci_do_get_cd(struct sdhci_host *host);

#ifdef CONFIG_PM
@@ -496,7 +495,7 @@ static int sdhci_adma_table_pre(struct s
goto fail;
BUG_ON(host->align_addr & host->align_mask);

- host->sg_count = sdhci_pre_dma_transfer(host, data, NULL);
+ host->sg_count = sdhci_pre_dma_transfer(host, data);
if (host->sg_count < 0)
goto unmap_align;

@@ -635,9 +634,11 @@ static void sdhci_adma_table_post(struct
}
}

- if (!data->host_cookie)
+ if (data->host_cookie == COOKIE_MAPPED) {
dma_unmap_sg(mmc_dev(host->mmc), data->sg,
data->sg_len, direction);
+ data->host_cookie = COOKIE_UNMAPPED;
+ }
}

static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_command *cmd)
@@ -833,7 +834,7 @@ static void sdhci_prepare_data(struct sd
} else {
int sg_cnt;

- sg_cnt = sdhci_pre_dma_transfer(host, data, NULL);
+ sg_cnt = sdhci_pre_dma_transfer(host, data);
if (sg_cnt <= 0) {
/*
* This only happens when someone fed
@@ -949,11 +950,13 @@ static void sdhci_finish_data(struct sdh
if (host->flags & SDHCI_USE_ADMA)
sdhci_adma_table_post(host, data);
else {
- if (!data->host_cookie)
+ if (data->host_cookie == COOKIE_MAPPED) {
dma_unmap_sg(mmc_dev(host->mmc),
data->sg, data->sg_len,
(data->flags & MMC_DATA_READ) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE);
+ data->host_cookie = COOKIE_UNMAPPED;
+ }
}
}

@@ -2099,49 +2102,36 @@ static void sdhci_post_req(struct mmc_ho
struct mmc_data *data = mrq->data;

if (host->flags & SDHCI_REQ_USE_DMA) {
- if (data->host_cookie)
+ if (data->host_cookie == COOKIE_GIVEN ||
+ data->host_cookie == COOKIE_MAPPED)
dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
data->flags & MMC_DATA_WRITE ?
DMA_TO_DEVICE : DMA_FROM_DEVICE);
- mrq->data->host_cookie = 0;
+ data->host_cookie = COOKIE_UNMAPPED;
}
}

static int sdhci_pre_dma_transfer(struct sdhci_host *host,
- struct mmc_data *data,
- struct sdhci_host_next *next)
+ struct mmc_data *data)
{
int sg_count;

- if (!next && data->host_cookie &&
- data->host_cookie != host->next_data.cookie) {
- pr_debug(DRIVER_NAME "[%s] invalid cookie: %d, next-cookie %d\n",
- __func__, data->host_cookie, host->next_data.cookie);
- data->host_cookie = 0;
+ if (data->host_cookie == COOKIE_MAPPED) {
+ data->host_cookie = COOKIE_GIVEN;
+ return data->sg_count;
}

- /* Check if next job is already prepared */
- if (next ||
- (!next && data->host_cookie != host->next_data.cookie)) {
- sg_count = dma_map_sg(mmc_dev(host->mmc), data->sg,
- data->sg_len,
- data->flags & MMC_DATA_WRITE ?
- DMA_TO_DEVICE : DMA_FROM_DEVICE);
-
- } else {
- sg_count = host->next_data.sg_count;
- host->next_data.sg_count = 0;
- }
+ WARN_ON(data->host_cookie == COOKIE_GIVEN);

+ sg_count = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+ data->flags & MMC_DATA_WRITE ?
+ DMA_TO_DEVICE : DMA_FROM_DEVICE);

if (sg_count == 0)
- return -EINVAL;
+ return -ENOSPC;

- if (next) {
- next->sg_count = sg_count;
- data->host_cookie = ++next->cookie < 0 ? 1 : next->cookie;
- } else
- host->sg_count = sg_count;
+ data->sg_count = sg_count;
+ data->host_cookie = COOKIE_MAPPED;

return sg_count;
}
@@ -2151,16 +2141,10 @@ static void sdhci_pre_req(struct mmc_hos
{
struct sdhci_host *host = mmc_priv(mmc);

- if (mrq->data->host_cookie) {
- mrq->data->host_cookie = 0;
- return;
- }
+ mrq->data->host_cookie = COOKIE_UNMAPPED;

if (host->flags & SDHCI_REQ_USE_DMA)
- if (sdhci_pre_dma_transfer(host,
- mrq->data,
- &host->next_data) < 0)
- mrq->data->host_cookie = 0;
+ sdhci_pre_dma_transfer(host, mrq->data);
}

static void sdhci_card_event(struct mmc_host *mmc)
@@ -3032,7 +3016,6 @@ int sdhci_add_host(struct sdhci_host *ho
host->max_clk = host->ops->get_max_clock(host);
}

- host->next_data.cookie = 1;
/*
* In case of Host Controller v3.00, find out whether clock
* multiplier is supported.
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -309,9 +309,10 @@ struct sdhci_adma2_64_desc {
*/
#define SDHCI_MAX_SEGS 128

-struct sdhci_host_next {
- unsigned int sg_count;
- s32 cookie;
+enum sdhci_cookie {
+ COOKIE_UNMAPPED,
+ COOKIE_MAPPED,
+ COOKIE_GIVEN,
};

struct sdhci_host {
@@ -503,7 +504,6 @@ struct sdhci_host {
unsigned int tuning_mode; /* Re-tuning mode supported by host */
#define SDHCI_TUNING_MODE_1 0

- struct sdhci_host_next next_data;
unsigned long private[0] ____cacheline_aligned;
};