This patch series add a support for rxe driver.
A dma-buf based memory registering has beed introduced to use the memory
region that lack of associated page structures (e.g. device memory and CMA
managed memory) [1]. However, to use the dma-buf based memory, each rdma
device drivers require add some implementation. The rxe driver has not
support yet.
[1] https://www.spinics.net/lists/linux-rdma/msg98592.html
To enable to use the memories in rxe rdma device, add some changes and
implementation in this patch series.
This series consists of three patches. The first patch changes the IB core
to support for rdma drivers that have not real dma device. The second
patch extracts a memory mapping process of rxe as a common function to use
a dma-buf support. The third patch adds the dma-buf support to rxe driver.
Related user space RDMA library changes are provided as a separate
patch.
Shunsuke Mie (3):
RDMA/umem: Change for rdma devices has not dma device
RDMA/rxe: Extract a mapping process into a function
RDMA/rxe: Support dma-buf as memory region
drivers/infiniband/core/umem_dmabuf.c | 2 +-
drivers/infiniband/sw/rxe/rxe_loc.h | 3 +
drivers/infiniband/sw/rxe/rxe_mr.c | 186 +++++++++++++++++++++-----
drivers/infiniband/sw/rxe/rxe_verbs.c | 36 +++++
4 files changed, 193 insertions(+), 34 deletions(-)
--
2.17.1
Implement a ib device operation ‘reg_user_mr_dmabuf’. Import dma-buf
using the IB core API and map the memory area linked the dma-buf.
Signed-off-by: Shunsuke Mie <[email protected]>
---
drivers/infiniband/sw/rxe/rxe_loc.h | 3 +
drivers/infiniband/sw/rxe/rxe_mr.c | 101 ++++++++++++++++++++++++++
drivers/infiniband/sw/rxe/rxe_verbs.c | 36 +++++++++
3 files changed, 140 insertions(+)
diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
index 1ddb20855dee..206d9d5f8bbf 100644
--- a/drivers/infiniband/sw/rxe/rxe_loc.h
+++ b/drivers/infiniband/sw/rxe/rxe_loc.h
@@ -75,6 +75,9 @@ u8 rxe_get_next_key(u32 last_key);
void rxe_mr_init_dma(struct rxe_pd *pd, int access, struct rxe_mr *mr);
int rxe_mr_init_user(struct rxe_pd *pd, u64 start, u64 length, u64 iova,
int access, struct rxe_mr *mr);
+int rxe_mr_dmabuf_init_user(struct rxe_pd *pd, int fd, u64 start, u64 length,
+ u64 iova, int access, struct rxe_mr *mr);
+
int rxe_mr_init_fast(struct rxe_pd *pd, int max_pages, struct rxe_mr *mr);
int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
enum rxe_mr_copy_dir dir, u32 *crcp);
diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
index 8b08705ed62a..846f52aad0de 100644
--- a/drivers/infiniband/sw/rxe/rxe_mr.c
+++ b/drivers/infiniband/sw/rxe/rxe_mr.c
@@ -4,6 +4,8 @@
* Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
*/
+#include <linux/dma-buf.h>
+
#include "rxe.h"
#include "rxe_loc.h"
@@ -207,6 +209,105 @@ int rxe_mr_init_user(struct rxe_pd *pd, u64 start, u64 length, u64 iova,
return err;
}
+static int rxe_map_dmabuf_mr(struct rxe_mr *mr)
+{
+ struct ib_umem_dmabuf *umem_dmabuf = to_ib_umem_dmabuf(mr->umem);
+ struct ib_umem *umem = mr->umem;
+ int err;
+
+ err = ib_umem_dmabuf_map_pages(umem_dmabuf);
+ if (err)
+ goto err1;
+
+ err = rxe_mr_gen_map(mr, umem);
+ if (err)
+ goto err2;
+
+ return ib_umem_num_pages(umem);
+
+err2:
+ ib_umem_dmabuf_unmap_pages(umem_dmabuf);
+err1:
+ return err;
+}
+
+/* A function called from the dma-buf exporter when the mapped pages
+ * become invalid.
+ */
+static void rxe_ib_dmabuf_invalidate_cb(struct dma_buf_attachment *attach)
+{
+ int err;
+ struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv;
+ struct rxe_mr *mr = umem_dmabuf->private;
+
+ ib_umem_dmabuf_unmap_pages(umem_dmabuf);
+
+ /* all of memory region is immediately mapped again */
+ err = rxe_map_dmabuf_mr(mr);
+ if (err)
+ pr_err("%s: failed to map the dma-buf region", __func__);
+}
+
+static struct dma_buf_attach_ops rxe_ib_dmabuf_attach_ops = {
+ .move_notify = rxe_ib_dmabuf_invalidate_cb,
+};
+
+/* initialize a umem and map all the areas of dma-buf. */
+int rxe_mr_dmabuf_init_user(struct rxe_pd *pd, int fd, u64 start, u64 length,
+ u64 iova, int access, struct rxe_mr *mr)
+{
+ struct ib_umem_dmabuf *umem_dmabuf;
+ int num_buf;
+ int err;
+
+ umem_dmabuf = ib_umem_dmabuf_get(pd->ibpd.device, start, length, fd,
+ access, &rxe_ib_dmabuf_attach_ops);
+ if (IS_ERR(umem_dmabuf)) {
+ err = PTR_ERR(umem_dmabuf);
+ pr_err("%s: failed to get umem_dmabuf (%d)", __func__, err);
+ goto err1;
+ }
+
+ umem_dmabuf->private = mr;
+
+ mr->umem = &umem_dmabuf->umem;
+ mr->umem->iova = iova;
+ num_buf = ib_umem_num_pages(mr->umem);
+
+ rxe_mr_init(access, mr);
+
+ err = rxe_mr_alloc(mr, num_buf);
+ if (err)
+ goto err1;
+
+ mr->page_shift = PAGE_SHIFT;
+ mr->page_mask = PAGE_SIZE - 1;
+
+ mr->ibmr.pd = &pd->ibpd;
+ mr->access = access;
+ mr->length = length;
+ mr->iova = iova;
+ mr->va = start;
+ mr->offset = ib_umem_offset(mr->umem);
+ mr->state = RXE_MR_STATE_VALID;
+ mr->type = RXE_MR_TYPE_MR;
+
+ err = rxe_map_dmabuf_mr(mr);
+ if (err) {
+ pr_err("%s: failed to map the dma-buf region", __func__);
+ goto err2;
+ }
+
+ return 0;
+
+err2:
+ for (i = 0; i < mr->num_map; i++)
+ kfree(mr->map[i]);
+ kfree(mr->map);
+err1:
+ return err;
+}
+
int rxe_mr_init_fast(struct rxe_pd *pd, int max_pages, struct rxe_mr *mr)
{
int err;
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index c223959ac174..4a38c20730b3 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -959,6 +959,39 @@ static struct ib_mr *rxe_reg_user_mr(struct ib_pd *ibpd,
return ERR_PTR(err);
}
+static struct ib_mr *rxe_reg_user_mr_dmabuf(struct ib_pd *ibpd, u64 start,
+ u64 length, u64 iova, int fd,
+ int access, struct ib_udata *udata)
+{
+ int err;
+ struct rxe_dev *rxe = to_rdev(ibpd->device);
+ struct rxe_pd *pd = to_rpd(ibpd);
+ struct rxe_mr *mr;
+
+ mr = rxe_alloc(&rxe->mr_pool);
+ if (!mr) {
+ err = -ENOMEM;
+ goto err1;
+ }
+
+ rxe_add_index(mr);
+
+ rxe_add_ref(pd);
+
+ err = rxe_mr_dmabuf_init_user(pd, fd, start, length, iova, access, mr);
+ if (err)
+ goto err2;
+
+ return &mr->ibmr;
+
+err2:
+ rxe_drop_ref(pd);
+ rxe_drop_index(mr);
+ rxe_drop_ref(mr);
+err1:
+ return ERR_PTR(err);
+}
+
static struct ib_mr *rxe_alloc_mr(struct ib_pd *ibpd, enum ib_mr_type mr_type,
u32 max_num_sg)
{
@@ -1139,6 +1172,7 @@ static const struct ib_device_ops rxe_dev_ops = {
.query_qp = rxe_query_qp,
.query_srq = rxe_query_srq,
.reg_user_mr = rxe_reg_user_mr,
+ .reg_user_mr_dmabuf = rxe_reg_user_mr_dmabuf,
.req_notify_cq = rxe_req_notify_cq,
.resize_cq = rxe_resize_cq,
@@ -1181,6 +1215,8 @@ int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name)
}
rxe->tfm = tfm;
+ dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64));
+
err = ib_register_device(dev, ibdev_name, NULL);
if (err)
pr_warn("%s failed with error %d\n", __func__, err);
--
2.17.1
On Wed, Sep 8, 2021 at 2:16 PM Shunsuke Mie <[email protected]> wrote:
>
> This patch series add a support for rxe driver.
After applying the patches, please run rdma-core tests with the patched kernel.
Then fix all the problems in rdma-core.
Thanks
Zhu Yanjun
>
> A dma-buf based memory registering has beed introduced to use the memory
> region that lack of associated page structures (e.g. device memory and CMA
> managed memory) [1]. However, to use the dma-buf based memory, each rdma
> device drivers require add some implementation. The rxe driver has not
> support yet.
>
> [1] https://www.spinics.net/lists/linux-rdma/msg98592.html
>
> To enable to use the memories in rxe rdma device, add some changes and
> implementation in this patch series.
>
> This series consists of three patches. The first patch changes the IB core
> to support for rdma drivers that have not real dma device. The second
> patch extracts a memory mapping process of rxe as a common function to use
> a dma-buf support. The third patch adds the dma-buf support to rxe driver.
>
> Related user space RDMA library changes are provided as a separate
> patch.
>
> Shunsuke Mie (3):
> RDMA/umem: Change for rdma devices has not dma device
> RDMA/rxe: Extract a mapping process into a function
> RDMA/rxe: Support dma-buf as memory region
>
> drivers/infiniband/core/umem_dmabuf.c | 2 +-
> drivers/infiniband/sw/rxe/rxe_loc.h | 3 +
> drivers/infiniband/sw/rxe/rxe_mr.c | 186 +++++++++++++++++++++-----
> drivers/infiniband/sw/rxe/rxe_verbs.c | 36 +++++
> 4 files changed, 193 insertions(+), 34 deletions(-)
>
> --
> 2.17.1
>
2021年9月9日(木) 14:45 Zhu Yanjun <[email protected]>:
> After applying the patches, please run rdma-core tests with the patched kernel.
> Then fix all the problems in rdma-core.
I understand. I'd like to do the tests and fix it before posting the next
patches
Regards,
Shunsuke