Re: [PATCH rdma-core 1/5] verbs: Support dma-buf based memory region

Jason Gunthorpe
2020-11-23T18:01:59Z

On Mon, Nov 23, 2020 at 09:53:00AM -0800, Jianxin Xiong wrote:
> Add new API function and new provider method for registering dma-buf
> based memory region. Update the man page and bump the API version.
>
> Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
> kernel-headers/rdma/ib_user_ioctl_cmds.h | 14 ++++++++++++
> libibverbs/cmd_mr.c | 38 ++++++++++++++++++++++++++++++++
> libibverbs/driver.h | 7 ++++++
> libibverbs/dummy_ops.c | 11 +++++++++
> libibverbs/libibverbs.map.in | 6 +++++
> libibverbs/man/ibv_reg_mr.3 | 21 ++++++++++++++++--
> libibverbs/verbs.c | 19 ++++++++++++++++
> libibverbs/verbs.h | 10 +++++++++
> 8 files changed, 124 insertions(+), 2 deletions(-)
>
> diff --git a/kernel-headers/rdma/ib_user_ioctl_cmds.h b/kernel-headers/rdma/ib_user_ioctl_cmds.h
> index 7968a18..dafc7eb 100644
> +++ b/kernel-headers/rdma/ib_user_ioctl_cmds.h
> @@ -1,5 +1,6 @@
> /*
> * Copyright (c) 2018, Mellanox Technologies inc. All rights reserved.
> + * Copyright (c) 2020, Intel Corporation. All rights reserved.
> *
> * This software is available to you under a choice of one of two
> * licenses. You may choose to be licensed under the terms of the GNU
> @@ -251,6 +252,7 @@ enum uverbs_methods_mr {
> UVERBS_METHOD_MR_DESTROY,
> UVERBS_METHOD_ADVISE_MR,
> UVERBS_METHOD_QUERY_MR,
> + UVERBS_METHOD_REG_DMABUF_MR,
> };
>
> enum uverbs_attrs_mr_destroy_ids {
> @@ -272,6 +274,18 @@ enum uverbs_attrs_query_mr_cmd_attr_ids {
> UVERBS_ATTR_QUERY_MR_RESP_IOVA,
> };
>
> +enum uverbs_attrs_reg_dmabuf_mr_cmd_attr_ids {
> + UVERBS_ATTR_REG_DMABUF_MR_HANDLE,
> + UVERBS_ATTR_REG_DMABUF_MR_PD_HANDLE,
> + UVERBS_ATTR_REG_DMABUF_MR_OFFSET,
> + UVERBS_ATTR_REG_DMABUF_MR_LENGTH,
> + UVERBS_ATTR_REG_DMABUF_MR_IOVA,
> + UVERBS_ATTR_REG_DMABUF_MR_FD,
> + UVERBS_ATTR_REG_DMABUF_MR_ACCESS_FLAGS,
> + UVERBS_ATTR_REG_DMABUF_MR_RESP_LKEY,
> + UVERBS_ATTR_REG_DMABUF_MR_RESP_RKEY,
> +};
> +
> enum uverbs_attrs_create_counters_cmd_attr_ids {
> UVERBS_ATTR_CREATE_COUNTERS_HANDLE,
> };

Please put changes to kernel-headers/ into their own patch

There is a script to make that commit in kernel-headers/update

> diff --git a/libibverbs/cmd_mr.c b/libibverbs/cmd_mr.c
> index 42dbe42..91ce2ef 100644
> +++ b/libibverbs/cmd_mr.c
> @@ -1,5 +1,6 @@
> /*
> * Copyright (c) 2018 Mellanox Technologies, Ltd. All rights reserved.
> + * Copyright (c) 2020 Intel Corporation. All rights reserved.
> *
> * This software is available to you under a choice of one of two
> * licenses. You may choose to be licensed under the terms of the GNU
> @@ -116,3 +117,40 @@ int ibv_cmd_query_mr(struct ibv_pd *pd, struct verbs_mr *vmr,
> return 0;
> }
>
> +int ibv_cmd_reg_dmabuf_mr(struct ibv_pd *pd, uint64_t offset, size_t length,
> + uint64_t iova, int fd, int access,
> + struct verbs_mr *vmr)
> +{
> + DECLARE_COMMAND_BUFFER(cmdb, UVERBS_OBJECT_MR,
> + UVERBS_METHOD_REG_DMABUF_MR,
> + 9);
> + struct ib_uverbs_attr *handle;
> + uint32_t lkey, rkey;
> + int ret;
> +
> + handle = fill_attr_out_obj(cmdb, UVERBS_ATTR_REG_DMABUF_MR_HANDLE);
> + fill_attr_out_ptr(cmdb, UVERBS_ATTR_REG_DMABUF_MR_RESP_LKEY, &lkey);
> + fill_attr_out_ptr(cmdb, UVERBS_ATTR_REG_DMABUF_MR_RESP_RKEY, &rkey);
> +
> + fill_attr_in_obj(cmdb, UVERBS_ATTR_REG_DMABUF_MR_PD_HANDLE, pd->handle);
> + fill_attr_in_uint64(cmdb, UVERBS_ATTR_REG_DMABUF_MR_OFFSET, offset);
> + fill_attr_in_uint64(cmdb, UVERBS_ATTR_REG_DMABUF_MR_LENGTH, length);
> + fill_attr_in_uint64(cmdb, UVERBS_ATTR_REG_DMABUF_MR_IOVA, iova);
> + fill_attr_in_uint32(cmdb, UVERBS_ATTR_REG_DMABUF_MR_FD, fd);
> + fill_attr_in_uint32(cmdb, UVERBS_ATTR_REG_DMABUF_MR_ACCESS_FLAGS, access);
> +
> + ret = execute_ioctl(pd->context, cmdb);
> + if (ret)
> + return errno;
> +
> + vmr->ibv_mr.handle =
> + read_attr_obj(UVERBS_ATTR_REG_DMABUF_MR_HANDLE, handle);
> + vmr->ibv_mr.context = pd->context;
> + vmr->ibv_mr.lkey = lkey;
> + vmr->ibv_mr.rkey = rkey;
> + vmr->ibv_mr.pd = pd;
> + vmr->ibv_mr.addr = (void *)offset;
> + vmr->ibv_mr.length = length;
> + vmr->mr_type = IBV_MR_TYPE_MR;

Remove the extra spaces around the = please

> diff --git a/libibverbs/libibverbs.map.in b/libibverbs/libibverbs.map.in
> index b5ccaca..f67e1ef 100644
> +++ b/libibverbs/libibverbs.map.in
> @@ -148,6 +148,11 @@ IBVERBS_1.11 {
> _ibv_query_gid_table;
> } IBVERBS_1.10;
>
> +IBVERBS_1.12 {
> + global:
> + ibv_reg_dmabuf_mr;
> +} IBVERBS_1.11;

There are a few things missing for this, the github CI should throw
some errors, please check it and fix everything

After this you need to change libibverbs/CMakeLists.txt and update:

1 1.11.${PACKAGE_VERSION}

To
1 1.12.${PACKAGE_VERSION}

You also need to update debian/libibverbs1.symbols, check the git
history for examples

> +LATEST_SYMVER_FUNC(ibv_reg_dmabuf_mr, 1_12, "IBVERBS_1.12",
> + struct ibv_mr *,
> + struct ibv_pd *pd, uint64_t offset,
> + size_t length, int fd, int access)

Do not use LATEST_SYMVER_FUNC, it is only for special cases where we
have two implementations of the same function. A normal function and
the map file update is all that is needed

> diff --git a/libibverbs/verbs.h b/libibverbs/verbs.h
> index ee57e05..3961b1e 100644
> +++ b/libibverbs/verbs.h
> @@ -3,6 +3,7 @@
> * Copyright (c) 2004, 2011-2012 Intel Corporation. All rights reserved.
> * Copyright (c) 2005, 2006, 2007 Cisco Systems, Inc. All rights reserved.
> * Copyright (c) 2005 PathScale, Inc. All rights reserved.
> + * Copyright (c) 2020 Intel Corporation. All rights reserved.
> *
> * This software is available to you under a choice of one of two
> * licenses. You may choose to be licensed under the terms of the GNU
> @@ -2133,6 +2134,9 @@ struct verbs_context {
> struct ibv_xrcd * (*open_xrcd)(struct ibv_context *context,
> struct ibv_xrcd_init_attr *xrcd_init_attr);
> int (*close_xrcd)(struct ibv_xrcd *xrcd);
> + struct ibv_mr * (*reg_dmabuf_mr)(struct ibv_pd *pd, uint64_t offset,
> + size_t length, uint64_t iova,
> + int fd, int access);
> uint64_t _ABI_placeholder3;
> size_t sz; /* Must be immediately before struct ibv_context */
> struct ibv_context context; /* Must be last field in the struct */

No, delete this whole hunk, it is not needed

Jason