This is a note to let you know that I've just added the patch titled
RDMA/mlx5: Set mkeys for dmabuf at PAGE_SIZE
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rdma-mlx5-set-mkeys-for-dmabuf-at-page_size.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 82e6fb4d49ed7bd6d9b0c557008c540d795c9976
Author: Chiara Meiohas <cmeiohas@xxxxxxxxxx>
Date: Thu Jun 13 21:01:42 2024 +0300
RDMA/mlx5: Set mkeys for dmabuf at PAGE_SIZE
[ Upstream commit a4e540119be565f47c305f295ed43f8e0bc3f5c3 ]
Set the mkey for dmabuf at PAGE_SIZE to support any SGL
after a move operation.
ib_umem_find_best_pgsz returns 0 on error, so it is
incorrect to check the returned page_size against PAGE_SIZE
Fixes: 90da7dc8206a ("RDMA/mlx5: Support dma-buf based userspace memory region")
Signed-off-by: Chiara Meiohas <cmeiohas@xxxxxxxxxx>
Reviewed-by: Michael Guralnik <michaelgur@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1e2289b9133e89f273a4e68d459057d032cbc2ce.1718301631.git.leon@xxxxxxxxxx
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index bf20a388eabe1..08c59c5a1e108 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -109,6 +109,19 @@ unsigned long __mlx5_umem_find_best_quantized_pgoff(
__mlx5_bit_sz(typ, page_offset_fld), 0, scale, \
page_offset_quantized)
+static inline unsigned long
+mlx5_umem_dmabuf_find_best_pgsz(struct ib_umem_dmabuf *umem_dmabuf)
+{
+ /*
+ * mkeys used for dmabuf are fixed at PAGE_SIZE because we must be able
+ * to hold any sgl after a move operation. Ideally the mkc page size
+ * could be changed at runtime to be optimal, but right now the driver
+ * cannot do that.
+ */
+ return ib_umem_find_best_pgsz(&umem_dmabuf->umem, PAGE_SIZE,
+ umem_dmabuf->umem.iova);
+}
+
enum {
MLX5_IB_MMAP_OFFSET_START = 9,
MLX5_IB_MMAP_OFFSET_END = 255,
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index fcf6447b4a4e0..66e53e895d341 100644
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -704,10 +704,8 @@ static int pagefault_dmabuf_mr(struct mlx5_ib_mr *mr, size_t bcnt,
return err;
}
- page_size = mlx5_umem_find_best_pgsz(&umem_dmabuf->umem, mkc,
- log_page_size, 0,
- umem_dmabuf->umem.iova);
- if (unlikely(page_size < PAGE_SIZE)) {
+ page_size = mlx5_umem_dmabuf_find_best_pgsz(umem_dmabuf);
+ if (!page_size) {
ib_umem_dmabuf_unmap_pages(umem_dmabuf);
err = -EINVAL;
} else {
