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

Logan Gunthorpe logang at deltatee.com
Tue Apr 25 18:21:03 UTC 2017


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 at deltatee.com>
Cc: Adrian Hunter <adrian.hunter at intel.com>
Cc: Ulf Hansson <ulf.hansson at 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



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