[PATCH v2 16/21] mmc: sdhci: Make use of the new sg_map helper function

Logan Gunthorpe
2017-04-25T18:21:25Z

Straightforward conversion, except due to the lack of an error path we
have to use SG_MAP_MUST_NOT_FAIL which may BUG_ON in certain cases
in the future.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
---
drivers/mmc/host/sdhci.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ecd0d43..239507f 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -513,15 +513,19 @@ static int sdhci_pre_dma_transfer(struct sdhci_host *host,
return sg_count;
}

+/*
+ * Note this function may return PTR_ERR and must be checked.
+ */
static char *sdhci_kmap_atomic(struct scatterlist *sg, unsigned long *flags)
{
local_irq_save(*flags);
- return kmap_atomic(sg_page(sg)) + sg->offset;
+ return sg_map(sg, 0, SG_KMAP_ATOMIC | SG_MAP_MUST_NOT_FAIL);
}

-static void sdhci_kunmap_atomic(void *buffer, unsigned long *flags)
+static void sdhci_kunmap_atomic(struct scatterlist *sg, void *buffer,
+ unsigned long *flags)
{
- kunmap_atomic(buffer);
+ sg_unmap(sg, buffer, 0, SG_KMAP_ATOMIC);
local_irq_restore(*flags);
}

@@ -585,7 +589,7 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
if (data->flags & MMC_DATA_WRITE) {
buffer = sdhci_kmap_atomic(sg, &flags);
memcpy(align, buffer, offset);
- sdhci_kunmap_atomic(buffer, &flags);
+ sdhci_kunmap_atomic(sg, buffer, &flags);
}

/* tran, valid */
@@ -663,7 +667,7 @@ static void sdhci_adma_table_post(struct sdhci_host *host,

buffer = sdhci_kmap_atomic(sg, &flags);
memcpy(buffer, align, size);
- sdhci_kunmap_atomic(buffer, &flags);
+ sdhci_kunmap_atomic(sg, buffer, &flags);

align += SDHCI_ADMA2_ALIGN;
}
--
2.1.4