diff mbox series

[3/7] mmc: mvsdio: Map the virtual page for PIO

Message ID 20240125-mmc-proper-kmap-v1-3-ba953c1ac3f9@linaro.org (mailing list archive)
State New, archived
Headers show
Series mmc: Try to do proper kmap_local() for scatterlists | expand

Commit Message

Linus Walleij Jan. 25, 2024, 2:37 p.m. UTC 
Use kmap_local_page() instead of sg_virt() to obtain a page
from the scatterlist: sg_virt() will not perform bounce
buffering if the page happens to be located in high memory,
which the driver may or may not be using.

Suggested-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-mmc/20240122073423.GA25859@lst.de/
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/mmc/host/mvsdio.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/mmc/host/mvsdio.c b/drivers/mmc/host/mvsdio.c
index ca01b7d204ba..a004a523bd2a 100644
--- a/drivers/mmc/host/mvsdio.c
+++ b/drivers/mmc/host/mvsdio.c
@@ -115,7 +115,7 @@  static int mvsd_setup_data(struct mvsd_host *host, struct mmc_data *data)
 		 * boundary.
 		 */
 		host->pio_size = data->blocks * data->blksz;
-		host->pio_ptr = sg_virt(data->sg);
+		host->pio_ptr = kmap_local_page(sg_page(data->sg));
 		if (!nodma)
 			dev_dbg(host->dev, "fallback to PIO for data at 0x%p size %d\n",
 				host->pio_ptr, host->pio_size);
@@ -289,6 +289,7 @@  static u32 mvsd_finish_data(struct mvsd_host *host, struct mmc_data *data,
 	void __iomem *iobase = host->base;
 
 	if (host->pio_ptr) {
+		kunmap_local(host->pio_ptr);
 		host->pio_ptr = NULL;
 		host->pio_size = 0;
 	} else {