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Use proper dma-buf API for that. Signed-off-by: Pavel Begunkov --- examples/zcrx.c | 40 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-) diff --git a/examples/zcrx.c b/examples/zcrx.c index b55b07ce..47036a33 100644 --- a/examples/zcrx.c +++ b/examples/zcrx.c @@ -39,6 +39,7 @@ #include #include +#include #include "liburing.h" #include "helpers.h" @@ -103,12 +104,46 @@ static unsigned long area_token; static bool stop; static __u32 zcrx_id; -static int dmabuf_fd; +static int dmabuf_fd = -1; static int memfd; static int listen_fd; static int target_cpu = -1; +static void dma_buf_begin_cpu_access(void) +{ + struct dma_buf_sync sync = { + .flags = DMA_BUF_SYNC_START | DMA_BUF_SYNC_RW, + }; + int ret; + + if (dmabuf_fd < 0) + return; + + ret = ioctl(dmabuf_fd, DMA_BUF_IOCTL_SYNC, &sync); + if (ret) { + fprintf(stderr, "sync failed %i\n", errno); + exit(1); + } +} + +static void dma_buf_end_cpu_access(void) +{ + struct dma_buf_sync sync = { + .flags = DMA_BUF_SYNC_END | DMA_BUF_SYNC_RW, + }; + int ret; + + if (dmabuf_fd < 0) + return; + + ret = ioctl(dmabuf_fd, DMA_BUF_IOCTL_SYNC, &sync); + if (ret) { + fprintf(stderr, "sync failed %i\n", errno); + exit(1); + } +} + static int get_sock_cpu(int sockfd) { int cpu; @@ -373,6 +408,8 @@ static void verify_data(__u8 *data, size_t size, unsigned long seq) if (!cfg_verify_data) return; + dma_buf_begin_cpu_access(); + for (i = 0; i < size; i++) { __u8 expected = (__u8)'a' + (seq + i) % 26; __u8 v = data[i]; @@ -382,6 +419,7 @@ static void verify_data(__u8 *data, size_t size, unsigned long seq) (unsigned)i, expected, v, (int)expected - v, seq, seq + i); } + dma_buf_end_cpu_access(); } static unsigned rq_nr_queued(struct io_uring_zcrx_rq *rq) -- 2.54.0