Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f490965b authored by Ping Jiang's avatar Ping Jiang
Browse files

char: virtio_fastrpc: use DMA_ATTR_SKIP_CPU_SYNC for uncached buffer 



When buffer is uncached, use flag DMA_ATTR_SKIP_CPU_SYNC to
reduce cache sync time.

Change-Id: Icce9cd40fc6f3cd6aba69443c593b3947d8c6fdb
Signed-off-by: default avatarPing Jiang <scottjiang@codeaurora.org>
parent 6bddfdd3

drivers/char/virtio_fastrpc.c

+11 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/dma-buf.h>

#include <linux/err.h>

#include <linux/interrupt.h>

#include <linux/ion.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/module.h>
@@ -512,6 +513,7 @@ static int fastrpc_mmap_create(struct fastrpc_file *fl, int fd, 
	struct fastrpc_apps *me = &gfa;

	struct fastrpc_mmap *map = NULL;

	int err = 0, sgl_index = 0;

	unsigned long flags;

	struct scatterlist *sgl = NULL;



	map = kzalloc(sizeof(*map), GFP_KERNEL);
@@ -535,12 +537,21 @@ static int fastrpc_mmap_create(struct fastrpc_file *fl, int fd, 
			dev_err(me->dev, "can't get dma buf fd %d\n", fd);

			goto bail;

		}

		VERIFY(err, !dma_buf_get_flags(map->buf, &flags));

		if (err) {

			dev_err(me->dev, "can't get dma buf flags %d\n", fd);

			goto bail;

		}



		VERIFY(err, !IS_ERR_OR_NULL(map->attach =

					dma_buf_attach(map->buf, me->dev)));

		if (err) {

			dev_err(me->dev, "can't attach dma buf\n");

			goto bail;

		}



		if (!(flags & ION_FLAG_CACHED))

			map->attach->dma_map_attrs |= DMA_ATTR_SKIP_CPU_SYNC;

		VERIFY(err, !IS_ERR_OR_NULL(map->table =

					dma_buf_map_attachment(map->attach,

					DMA_BIDIRECTIONAL)));