diff mbox series

[4/7] mmc: bcm2835: Avoid possible races on data requests

Message ID 1541943930-23873-5-git-send-email-stefan.wahren@i2se.com (mailing list archive)
State New, archived
Headers show
Series mmc: Several fixes for bcm2835 driver | expand

Commit Message

Stefan Wahren Nov. 11, 2018, 1:45 p.m. UTC 
There are two accesses on the data requests which are not protected by
the mutex. So fix this accordingly.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/mmc/host/bcm2835.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index 45724ef..1c60798 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c
@@ -1064,10 +1064,12 @@  static void bcm2835_dma_complete_work(struct work_struct *work)
 {
 	struct bcm2835_host *host =
 		container_of(work, struct bcm2835_host, dma_work);
-	struct mmc_data *data = host->data;
+	struct mmc_data *data;
 
 	mutex_lock(&host->mutex);
 
+	data = host->data;
+
 	if (host->dma_chan) {
 		dma_unmap_sg(host->dma_chan->device->dev,
 			     data->sg, data->sg_len,
@@ -1192,9 +1194,6 @@  static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq)
 		return;
 	}
 
-	if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD))
-		bcm2835_prepare_dma(host, mrq->data);
-
 	mutex_lock(&host->mutex);
 
 	WARN_ON(host->mrq);
@@ -1218,6 +1217,9 @@  static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq)
 		return;
 	}
 
+	if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD))
+		bcm2835_prepare_dma(host, mrq->data);
+
 	host->use_sbc = !!mrq->sbc && host->mrq->data &&
 			(host->mrq->data->flags & MMC_DATA_READ);
 	if (host->use_sbc) {