[PATCH iproute2-next v5 0/5] Add vdpa device management tool

[PATCH iproute2-next v5 0/5] Add vdpa device management tool

[Parav Pandit]

Linux vdpa interface allows vdpa device management functionality.
This includes adding, removing, querying vdpa devices.

vdpa interface also includes showing supported management devices
which support such operations.

This patchset includes kernel uapi headers and a vdpa tool.

examples:

$ vdpa mgmtdev show
vdpasim:
  supported_classes net

$ vdpa mgmtdev show -jp
{
    "show": {
        "vdpasim": {
            "supported_classes": [ "net" ]
        }
    }
}

Create a vdpa device of type networking named as "foo2" from
the management device vdpasim_net:

$ vdpa dev add mgmtdev vdpasim_net name foo2

Show the newly created vdpa device by its name:
$ vdpa dev show foo2
foo2: type network mgmtdev vdpasim_net vendor_id 0 max_vqs 2 max_vq_size 256

$ vdpa dev show foo2 -jp
{
    "dev": {
        "foo2": {
            "type": "network",
            "mgmtdev": "vdpasim_net",
            "vendor_id": 0,
            "max_vqs": 2,
            "max_vq_size": 256
        }
    }
}

Delete the vdpa device after its use:
$ vdpa dev del foo2

An example of PCI PF, VF and SF management device:
pci/0000:03.00:0
  supported_classes
    net
pci/0000:03.00:4
  supported_classes
    net
auxiliary/mlx5_core.sf.8
  supported_classes
    net

Patch summary:
Patch-1 adds kernel headers for vdpa subsystem
Patch-2 adds library routines for indent handling
Patch-3 adds library routines for generic socket communication
PAtch-4 adds library routine for number to string mapping
Patch-5 adds vdpa tool

Kernel headers are from the linux-next [1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

---
changelog:
v4->v5:
 - avoided UAPI prefix in the vdpa.h header file
 - updated commit id to commit of linux-next tree
v3->v4:
 - relocated vdpa headers to vdpa/include/uapi/linux
 - added new headers path to CFLAGS of vdpa tool
v2->v3:
 - addressed David's comment to split patch for utils and other parts
 - rebased
 - using newly added helper routine for number to string mapping
v1->v2:
 - addressed below comments from David
 - added and used library helpers for socket communication
 - added and used library functions for string processing helpers
 - added and used library functions indent processing helpers


Parav Pandit (5):
  Add kernel headers
  utils: Add helper routines for indent handling
  utils: Add generic socket helpers
  utils: Add helper to map string to unsigned int
  vdpa: Add vdpa tool

 Makefile                             |   2 +-
 include/mnl_utils.h                  |  16 +
 include/utils.h                      |  20 +-
 lib/mnl_utils.c                      | 121 +++++
 lib/utils.c                          |  83 +++-
 man/man8/vdpa-dev.8                  |  96 ++++
 man/man8/vdpa-mgmtdev.8              |  53 +++
 man/man8/vdpa.8                      |  76 +++
 vdpa/Makefile                        |  25 +
 vdpa/include/uapi/linux/vdpa.h       |  40 ++
 vdpa/include/uapi/linux/virtio_ids.h |  58 +++
 vdpa/vdpa.c                          | 675 +++++++++++++++++++++++++++
 12 files changed, 1261 insertions(+), 4 deletions(-)
 create mode 100644 man/man8/vdpa-dev.8
 create mode 100644 man/man8/vdpa-mgmtdev.8
 create mode 100644 man/man8/vdpa.8
 create mode 100644 vdpa/Makefile
 create mode 100644 vdpa/include/uapi/linux/vdpa.h
 create mode 100644 vdpa/include/uapi/linux/virtio_ids.h
 create mode 100644 vdpa/vdpa.c

-- 
2.26.2

[PATCH iproute2-next v5 1/5] Add kernel headers

[Parav Pandit]

Add kernel headers to commit from kernel tree [1].
  6acba4951632 ("vdpa_sim_net: Add support for user supported devices")

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v4->v5:
 - avoided UAPI prefix in the vdpa.h header file
 - updated commit id to commit of linux-next tree
v3->v4:
 - relocated header files to vdpa/include/uapi/linux
---
 vdpa/include/uapi/linux/vdpa.h       | 40 +++++++++++++++++++
 vdpa/include/uapi/linux/virtio_ids.h | 58 ++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+)
 create mode 100644 vdpa/include/uapi/linux/vdpa.h
 create mode 100644 vdpa/include/uapi/linux/virtio_ids.h

diff --git a/vdpa/include/uapi/linux/vdpa.h b/vdpa/include/uapi/linux/vdpa.h
new file mode 100644
index 00000000..37ae26b6
--- /dev/null
+++ b/vdpa/include/uapi/linux/vdpa.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * vdpa device management interface
+ * Copyright (c) 2020 Mellanox Technologies Ltd. All rights reserved.
+ */
+
+#ifndef _LINUX_VDPA_H_
+#define _LINUX_VDPA_H_
+
+#define VDPA_GENL_NAME "vdpa"
+#define VDPA_GENL_VERSION 0x1
+
+enum vdpa_command {
+	VDPA_CMD_UNSPEC,
+	VDPA_CMD_MGMTDEV_NEW,
+	VDPA_CMD_MGMTDEV_GET,		/* can dump */
+	VDPA_CMD_DEV_NEW,
+	VDPA_CMD_DEV_DEL,
+	VDPA_CMD_DEV_GET,		/* can dump */
+};
+
+enum vdpa_attr {
+	VDPA_ATTR_UNSPEC,
+
+	/* bus name (optional) + dev name together make the parent device handle */
+	VDPA_ATTR_MGMTDEV_BUS_NAME,		/* string */
+	VDPA_ATTR_MGMTDEV_DEV_NAME,		/* string */
+	VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES,	/* u64 */
+
+	VDPA_ATTR_DEV_NAME,			/* string */
+	VDPA_ATTR_DEV_ID,			/* u32 */
+	VDPA_ATTR_DEV_VENDOR_ID,		/* u32 */
+	VDPA_ATTR_DEV_MAX_VQS,			/* u32 */
+	VDPA_ATTR_DEV_MAX_VQ_SIZE,		/* u16 */
+
+	/* new attributes must be added above here */
+	VDPA_ATTR_MAX,
+};
+
+#endif
diff --git a/vdpa/include/uapi/linux/virtio_ids.h b/vdpa/include/uapi/linux/virtio_ids.h
new file mode 100644
index 00000000..bc1c0621
--- /dev/null
+++ b/vdpa/include/uapi/linux/virtio_ids.h
@@ -0,0 +1,58 @@
+#ifndef _LINUX_VIRTIO_IDS_H
+#define _LINUX_VIRTIO_IDS_H
+/*
+ * Virtio IDs
+ *
+ * This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
+
+#define VIRTIO_ID_NET			1 /* virtio net */
+#define VIRTIO_ID_BLOCK			2 /* virtio block */
+#define VIRTIO_ID_CONSOLE		3 /* virtio console */
+#define VIRTIO_ID_RNG			4 /* virtio rng */
+#define VIRTIO_ID_BALLOON		5 /* virtio balloon */
+#define VIRTIO_ID_IOMEM			6 /* virtio ioMemory */
+#define VIRTIO_ID_RPMSG			7 /* virtio remote processor messaging */
+#define VIRTIO_ID_SCSI			8 /* virtio scsi */
+#define VIRTIO_ID_9P			9 /* 9p virtio console */
+#define VIRTIO_ID_MAC80211_WLAN		10 /* virtio WLAN MAC */
+#define VIRTIO_ID_RPROC_SERIAL		11 /* virtio remoteproc serial link */
+#define VIRTIO_ID_CAIF			12 /* Virtio caif */
+#define VIRTIO_ID_MEMORY_BALLOON	13 /* virtio memory balloon */
+#define VIRTIO_ID_GPU			16 /* virtio GPU */
+#define VIRTIO_ID_CLOCK			17 /* virtio clock/timer */
+#define VIRTIO_ID_INPUT			18 /* virtio input */
+#define VIRTIO_ID_VSOCK			19 /* virtio vsock transport */
+#define VIRTIO_ID_CRYPTO		20 /* virtio crypto */
+#define VIRTIO_ID_SIGNAL_DIST		21 /* virtio signal distribution device */
+#define VIRTIO_ID_PSTORE		22 /* virtio pstore device */
+#define VIRTIO_ID_IOMMU			23 /* virtio IOMMU */
+#define VIRTIO_ID_MEM			24 /* virtio mem */
+#define VIRTIO_ID_FS			26 /* virtio filesystem */
+#define VIRTIO_ID_PMEM			27 /* virtio pmem */
+#define VIRTIO_ID_MAC80211_HWSIM	29 /* virtio mac80211-hwsim */
+
+#endif /* _LINUX_VIRTIO_IDS_H */
-- 
2.26.2

[PATCH iproute2-next v5 2/5] utils: Add helper routines for indent handling

[Parav Pandit]

Subsequent patch needs to use 2 char indentation for nested objects.
Hence introduce a generic helpers to allocate, deallocate, increment,
decrement and to print indent block.

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v2->v3:
 - patch split from vdpa tool patch
---
 include/utils.h | 16 ++++++++++++
 lib/utils.c     | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 82 insertions(+)

diff --git a/include/utils.h b/include/utils.h
index e66090ae..9b76c92a 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -349,4 +349,20 @@ int str_map_lookup_str(const struct str_num_map *map, const char *needle);
 const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val);
 const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val);
 
+unsigned int get_str_char_count(const char *str, int match);
+int str_split_by_char(char *str, char **before, char **after, int match);
+
+#define INDENT_STR_MAXLEN 32
+
+struct indent_mem {
+	int indent_level;
+	char indent_str[INDENT_STR_MAXLEN + 1];
+};
+
+struct indent_mem *alloc_indent_mem(void);
+void free_indent_mem(struct indent_mem *mem);
+void inc_indent(struct indent_mem *mem);
+void dec_indent(struct indent_mem *mem);
+void print_indent(struct indent_mem *mem);
+
 #endif /* __UTILS_H__ */
diff --git a/lib/utils.c b/lib/utils.c
index af1b553c..cc6d0e34 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1978,3 +1978,69 @@ const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val)
 	}
 	return NULL;
 }
+
+unsigned int get_str_char_count(const char *str, int match)
+{
+	unsigned int count = 0;
+	const char *pos = str;
+
+	while ((pos = strchr(pos, match))) {
+		count++;
+		pos++;
+	}
+	return count;
+}
+
+int str_split_by_char(char *str, char **before, char **after, int match)
+{
+	char *slash;
+
+	slash = strrchr(str, match);
+	if (!slash)
+		return -EINVAL;
+	*slash = '\0';
+	*before = str;
+	*after = slash + 1;
+	return 0;
+}
+
+struct indent_mem *alloc_indent_mem(void)
+{
+	struct indent_mem *mem = malloc(sizeof(*mem));
+
+	if (!mem)
+		return NULL;
+	strcpy(mem->indent_str, "");
+	mem->indent_level = 0;
+	return mem;
+}
+
+void free_indent_mem(struct indent_mem *mem)
+{
+	free(mem);
+}
+
+#define INDENT_STR_STEP 2
+
+void inc_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level + INDENT_STR_STEP > INDENT_STR_MAXLEN)
+		return;
+	mem->indent_level += INDENT_STR_STEP;
+	memset(mem->indent_str, ' ', sizeof(mem->indent_str));
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void dec_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level - INDENT_STR_STEP < 0)
+		return;
+	mem->indent_level -= INDENT_STR_STEP;
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void print_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level)
+		printf("%s", mem->indent_str);
+}
-- 
2.26.2

[PATCH iproute2-next v5 3/5] utils: Add generic socket helpers

[Parav Pandit]

Subsequent patch needs to
(a) query and use socket family
(b) send/receive messages using this family

Hence add helper routines to open, close, query family and to perform
send receive operations.

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v2->v3:
 - split patch from add vdpa tool for socket helpers
---
 include/mnl_utils.h |  16 ++++++
 lib/mnl_utils.c     | 121 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+)

diff --git a/include/mnl_utils.h b/include/mnl_utils.h
index fa826ef1..9e7d6879 100644
--- a/include/mnl_utils.h
+++ b/include/mnl_utils.h
@@ -2,6 +2,22 @@
 #ifndef __MNL_UTILS_H__
 #define __MNL_UTILS_H__ 1
 
+struct mnlu_gen_socket {
+	struct mnl_socket *nl;
+	char *buf;
+	uint32_t family;
+	unsigned int seq;
+	uint8_t version;
+};
+
+int mnlu_gen_socket_open(struct mnlu_gen_socket *nlg, const char *family_name,
+			 uint8_t version);
+void mnlu_gen_socket_close(struct mnlu_gen_socket *nlg);
+struct nlmsghdr *mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+					     uint8_t cmd, uint16_t flags);
+int mnlu_gen_socket_sndrcv(struct mnlu_gen_socket *nlg, const struct nlmsghdr *nlh,
+			   mnl_cb_t data_cb, void *data);
+
 struct mnl_socket *mnlu_socket_open(int bus);
 struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
 				  void *extra_header, size_t extra_header_size);
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
index 46384ff8..4f699455 100644
--- a/lib/mnl_utils.c
+++ b/lib/mnl_utils.c
@@ -7,6 +7,7 @@
 #include <string.h>
 #include <time.h>
 #include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
 
 #include "libnetlink.h"
 #include "mnl_utils.h"
@@ -108,3 +109,123 @@ int mnlu_socket_recv_run(struct mnl_socket *nl, unsigned int seq, void *buf, siz
 
 	return err;
 }
+
+static int get_family_id_attr_cb(const struct nlattr *attr, void *data)
+{
+	int type = mnl_attr_get_type(attr);
+	const struct nlattr **tb = data;
+
+	if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
+		return MNL_CB_ERROR;
+
+	if (type == CTRL_ATTR_FAMILY_ID &&
+	    mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
+		return MNL_CB_ERROR;
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int get_family_id_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+	struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
+	uint32_t *p_id = data;
+
+	mnl_attr_parse(nlh, sizeof(*genl), get_family_id_attr_cb, tb);
+	if (!tb[CTRL_ATTR_FAMILY_ID])
+		return MNL_CB_ERROR;
+	*p_id = mnl_attr_get_u16(tb[CTRL_ATTR_FAMILY_ID]);
+	return MNL_CB_OK;
+}
+
+static int family_get(struct mnlu_gen_socket *nlg, const char *family_name)
+{
+	struct genlmsghdr hdr = {};
+	struct nlmsghdr *nlh;
+	int err;
+
+	hdr.cmd = CTRL_CMD_GETFAMILY;
+	hdr.version = 0x1;
+
+	nlh = mnlu_msg_prepare(nlg->buf, GENL_ID_CTRL,
+			       NLM_F_REQUEST | NLM_F_ACK,
+			       &hdr, sizeof(hdr));
+
+	mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, family_name);
+
+	err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+	if (err < 0)
+		return err;
+
+	err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+				   MNL_SOCKET_BUFFER_SIZE,
+				   get_family_id_cb, &nlg->family);
+	return err;
+}
+
+int mnlu_gen_socket_open(struct mnlu_gen_socket *nlg, const char *family_name,
+			 uint8_t version)
+{
+	int err;
+
+	nlg->buf = malloc(MNL_SOCKET_BUFFER_SIZE);
+	if (!nlg->buf)
+		goto err_buf_alloc;
+
+	nlg->nl = mnlu_socket_open(NETLINK_GENERIC);
+	if (!nlg->nl)
+		goto err_socket_open;
+
+	err = family_get(nlg, family_name);
+	if (err)
+		goto err_socket;
+
+	return 0;
+
+err_socket:
+	mnl_socket_close(nlg->nl);
+err_socket_open:
+	free(nlg->buf);
+err_buf_alloc:
+	return -1;
+}
+
+void mnlu_gen_socket_close(struct mnlu_gen_socket *nlg)
+{
+	mnl_socket_close(nlg->nl);
+	free(nlg->buf);
+}
+
+struct nlmsghdr *mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+					     uint8_t cmd, uint16_t flags)
+{
+	struct genlmsghdr hdr = {};
+	struct nlmsghdr *nlh;
+
+	hdr.cmd = cmd;
+	hdr.version = nlg->version;
+	nlh = mnlu_msg_prepare(nlg->buf, nlg->family, flags, &hdr, sizeof(hdr));
+	nlg->seq = nlh->nlmsg_seq;
+	return nlh;
+}
+
+int mnlu_gen_socket_sndrcv(struct mnlu_gen_socket *nlg, const struct nlmsghdr *nlh,
+			   mnl_cb_t data_cb, void *data)
+{
+	int err;
+
+	err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+	if (err < 0) {
+		perror("Failed to send data");
+		return -errno;
+	}
+
+	err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+				   MNL_SOCKET_BUFFER_SIZE,
+				   data_cb, data);
+	if (err < 0) {
+		fprintf(stderr, "kernel answers: %s\n", strerror(errno));
+		return -errno;
+	}
+	return 0;
+}
-- 
2.26.2

[PATCH iproute2-next v5 4/5] utils: Add helper to map string to unsigned int

[Parav Pandit]

In subsequent patch need to map a string to a unsigned int.
Hence, add an API to map a string to unsigned int.

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v2->v3:
 - new patch to reuse string to unsigned int mapping
---
 include/utils.h |  4 +++-
 lib/utils.c     | 17 +++++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index 9b76c92a..b29c3798 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -342,10 +342,12 @@ int parse_mapping(int *argcp, char ***argvp, bool allow_all,
 
 struct str_num_map {
 	const char *str;
-	int num;
+	unsigned int num;
 };
 
 int str_map_lookup_str(const struct str_num_map *map, const char *needle);
+const char *str_map_lookup_uint(const struct str_num_map *map,
+				unsigned int val);
 const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val);
 const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val);
 
diff --git a/lib/utils.c b/lib/utils.c
index cc6d0e34..633f6359 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1953,9 +1953,22 @@ int str_map_lookup_str(const struct str_num_map *map, const char *needle)
 	return -EINVAL;
 }
 
+const char *str_map_lookup_uint(const struct str_num_map *map, unsigned int val)
+{
+	unsigned int num = val;
+
+	while (map && map->str) {
+		if (num == map->num)
+			return map->str;
+
+		map++;
+	}
+	return NULL;
+}
+
 const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val)
 {
-	int num = val;
+	unsigned int num = val;
 
 	while (map && map->str) {
 		if (num == map->num)
@@ -1968,7 +1981,7 @@ const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val)
 
 const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val)
 {
-	int num = val;
+	unsigned int num = val;
 
 	while (map && map->str) {
 		if (num == map->num)
-- 
2.26.2

[PATCH iproute2-next v5 5/5] vdpa: Add vdpa tool

[Parav Pandit]

vdpa tool is created to create, delete and query vdpa devices.
examples:
Show vdpa management device that supports creating, deleting vdpa devices.

$ vdpa mgmtdev show
vdpasim:
  supported_classes net

$ vdpa mgmtdev show -jp
{
    "show": {
        "vdpasim": {
            "supported_classes": [ "net" ]
        }
    }
}

Create a vdpa device of type networking named as "foo2" from
the management device vdpasim_net:

$ vdpa dev add mgmtdev vdpasim_net name foo2

Show the newly created vdpa device by its name:
$ vdpa dev show foo2
foo2: type network mgmtdev vdpasim_net vendor_id 0 max_vqs 2 max_vq_size 256

$ vdpa dev show foo2 -jp
{
    "dev": {
        "foo2": {
            "type": "network",
            "mgmtdev": "vdpasim_net",
            "vendor_id": 0,
            "max_vqs": 2,
            "max_vq_size": 256
        }
    }
}

Delete the vdpa device after its use:
$ vdpa dev del foo2

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v3->v4:
 - added new header file path vdpa/include/uapi/linux to CFLAGS
---
 Makefile                |   2 +-
 man/man8/vdpa-dev.8     |  96 ++++++
 man/man8/vdpa-mgmtdev.8 |  53 ++++
 man/man8/vdpa.8         |  76 +++++
 vdpa/Makefile           |  25 ++
 vdpa/vdpa.c             | 675 ++++++++++++++++++++++++++++++++++++++++
 6 files changed, 926 insertions(+), 1 deletion(-)
 create mode 100644 man/man8/vdpa-dev.8
 create mode 100644 man/man8/vdpa-mgmtdev.8
 create mode 100644 man/man8/vdpa.8
 create mode 100644 vdpa/Makefile
 create mode 100644 vdpa/vdpa.c

diff --git a/Makefile b/Makefile
index e64c6599..19bd163e 100644
--- a/Makefile
+++ b/Makefile
@@ -55,7 +55,7 @@ WFLAGS += -Wmissing-declarations -Wold-style-definition -Wformat=2
 CFLAGS := $(WFLAGS) $(CCOPTS) -I../include -I../include/uapi $(DEFINES) $(CFLAGS)
 YACCFLAGS = -d -t -v
 
-SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma dcb man
+SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma dcb man vdpa
 
 LIBNETLINK=../lib/libutil.a ../lib/libnetlink.a
 LDLIBS += $(LIBNETLINK)
diff --git a/man/man8/vdpa-dev.8 b/man/man8/vdpa-dev.8
new file mode 100644
index 00000000..36433519
--- /dev/null
+++ b/man/man8/vdpa-dev.8
@@ -0,0 +1,96 @@
+.TH DEVLINK\-DEV 8 "5 Jan 2021" "iproute2" "Linux"
+.SH NAME
+vdpa-dev \- vdpa device configuration
+.SH SYNOPSIS
+.sp
+.ad l
+.in +8
+.ti -8
+.B vdpa
+.B dev
+.RI "[ " OPTIONS " ] "
+.RI  " { " COMMAND | " "
+.BR help " }"
+.sp
+
+.ti -8
+.IR OPTIONS " := { "
+\fB\-V\fR[\fIersion\fR]
+}
+
+.ti -8
+.B vdpa dev show
+.RI "[ " DEV " ]"
+
+.ti -8
+.B vdpa dev help
+
+.ti -8
+.B vdpa dev add
+.B name
+.I NAME
+.B mgmtdev
+.I MGMTDEV
+
+.ti -8
+.B vdpa dev del
+.I DEV
+
+.SH "DESCRIPTION"
+.SS vdpa dev show - display vdpa device attributes
+
+.PP
+.I "DEV"
+- specifies the vdpa device to show.
+If this argument is omitted all devices are listed.
+
+.in +4
+Format is:
+.in +2
+VDPA_DEVICE_NAME
+
+.SS vdpa dev add - add a new vdpa device.
+
+.TP
+.BI name " NAME"
+Name of the new vdpa device to add.
+
+.TP
+.BI mgmtdev " MGMTDEV"
+Name of the management device to use for device addition.
+
+.SS vdpa dev del - Delete the vdpa device.
+
+.PP
+.I "DEV"
+- specifies the vdpa device to delete.
+
+.SH "EXAMPLES"
+.PP
+vdpa dev show
+.RS 4
+Shows the all vdpa devices on the system.
+.RE
+.PP
+vdpa dev show foo
+.RS 4
+Shows the specified vdpa device.
+.RE
+.PP
+vdpa dev add name foo mgmtdev vdpa_sim_net
+.RS 4
+Add the vdpa device named foo on the management device vdpa_sim_net.
+.RE
+.PP
+vdpa dev del foo
+.RS 4
+Delete the vdpa device named foo which was previously created.
+.RE
+
+.SH SEE ALSO
+.BR vdpa (8),
+.BR vdpa-mgmtdev (8),
+.br
+
+.SH AUTHOR
+Parav Pandit <parav@nvidia.com>
diff --git a/man/man8/vdpa-mgmtdev.8 b/man/man8/vdpa-mgmtdev.8
new file mode 100644
index 00000000..cae2cbd0
--- /dev/null
+++ b/man/man8/vdpa-mgmtdev.8
@@ -0,0 +1,53 @@
+.TH DEVLINK\-DEV 8 "5 Jan 2021" "iproute2" "Linux"
+.SH NAME
+vdpa-dev \- vdpa management device view
+.SH SYNOPSIS
+.sp
+.ad l
+.in +8
+.ti -8
+.B vdpa
+.B mgmtdev
+.RI  " { " COMMAND | " "
+.BR help " }"
+.sp
+
+.ti -8
+.IR OPTIONS " := { "
+\fB\-V\fR[\fIersion\fR]
+}
+
+.ti -8
+.B vdpa mgmtdev show
+.RI "[ " MGMTDEV " ]"
+
+.ti -8
+.B vdpa mgmtdev help
+
+.SH "DESCRIPTION"
+.SS vdpa mgmtdev show - display vdpa management device attributes
+
+.PP
+.I "MGMTDEV"
+- specifies the vdpa management device to show.
+If this argument is omitted all management devices are listed.
+
+.SH "EXAMPLES"
+.PP
+vdpa mgmtdev show
+.RS 4
+Shows all the vdpa management devices on the system.
+.RE
+.PP
+vdpa mgmtdev show bar
+.RS 4
+Shows the specified vdpa management device.
+.RE
+
+.SH SEE ALSO
+.BR vdpa (8),
+.BR vdpa-dev (8),
+.br
+
+.SH AUTHOR
+Parav Pandit <parav@nvidia.com>
diff --git a/man/man8/vdpa.8 b/man/man8/vdpa.8
new file mode 100644
index 00000000..d1aaecec
--- /dev/null
+++ b/man/man8/vdpa.8
@@ -0,0 +1,76 @@
+.TH VDPA 8 "5 Jan 2021" "iproute2" "Linux"
+.SH NAME
+vdpa \- vdpa management tool
+.SH SYNOPSIS
+.sp
+.ad l
+.in +8
+.ti -8
+.B vdpa
+.RI "[ " OPTIONS " ] { " dev | mgmtdev " } { " COMMAND " | "
+.BR help " }"
+.sp
+
+.SH OPTIONS
+
+.TP
+.BR "\-V" , " --Version"
+Print the version of the
+.B vdpa
+utility and exit.
+
+.TP
+.BR "\-j" , " --json"
+Generate JSON output.
+
+.TP
+.BR "\-p" , " --pretty"
+When combined with -j generate a pretty JSON output.
+
+.SS
+.I OBJECT
+
+.TP
+.B dev
+- vdpa device.
+
+.TP
+.B mgmtdev
+- vdpa management device.
+
+.SS
+.I COMMAND
+
+Specifies the action to perform on the object.
+The set of possible actions depends on the object type.
+It is possible to
+.B show
+(or
+.B list
+) objects. The
+.B help
+command is available for all objects. It prints
+out a list of available commands and argument syntax conventions.
+.sp
+If no command is given, some default command is assumed.
+Usually it is
+.B show
+or, if the objects of this class cannot be listed,
+.BR "help" .
+
+.SH EXIT STATUS
+Exit status is 0 if command was successful or a positive integer upon failure.
+
+.SH SEE ALSO
+.BR vdpa-dev (8),
+.BR vdpa-mgmtdev (8),
+.br
+
+.SH REPORTING BUGS
+Report any bugs to the Network Developers mailing list
+.B <netdev@vger.kernel.org>
+where the development and maintenance is primarily done.
+You do not have to be subscribed to the list to send a message there.
+
+.SH AUTHOR
+Parav Pandit <parav@nvidia.com>
diff --git a/vdpa/Makefile b/vdpa/Makefile
new file mode 100644
index 00000000..253e20a7
--- /dev/null
+++ b/vdpa/Makefile
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0
+include ../config.mk
+
+TARGETS :=
+
+ifeq ($(HAVE_MNL),y)
+
+CFLAGS += -I./include/uapi/
+VDPAOBJ = vdpa.o
+TARGETS += vdpa
+
+endif
+
+all: $(TARGETS) $(LIBS)
+
+vdpa: $(VDPAOBJ)
+	$(QUIET_LINK)$(CC) $^ $(LDFLAGS) $(LDLIBS) -o $@
+
+install: all
+	for i in $(TARGETS); \
+	do install -m 0755 $$i $(DESTDIR)$(SBINDIR); \
+	done
+
+clean:
+	rm -f $(VDPAOBJ) $(TARGETS)
diff --git a/vdpa/vdpa.c b/vdpa/vdpa.c
new file mode 100644
index 00000000..7fdb36b9
--- /dev/null
+++ b/vdpa/vdpa.c
@@ -0,0 +1,675 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <stdio.h>
+#include <getopt.h>
+#include <errno.h>
+#include <linux/genetlink.h>
+#include <linux/vdpa.h>
+#include <linux/virtio_ids.h>
+#include <linux/netlink.h>
+#include <libmnl/libmnl.h>
+#include "mnl_utils.h"
+
+#include "version.h"
+#include "json_print.h"
+#include "utils.h"
+
+#define VDPA_OPT_MGMTDEV_HANDLE		BIT(0)
+#define VDPA_OPT_VDEV_MGMTDEV_HANDLE	BIT(1)
+#define VDPA_OPT_VDEV_NAME		BIT(2)
+#define VDPA_OPT_VDEV_HANDLE		BIT(3)
+
+struct vdpa_opts {
+	uint64_t present; /* flags of present items */
+	char *mdev_bus_name;
+	char *mdev_name;
+	const char *vdev_name;
+	unsigned int device_id;
+};
+
+struct vdpa {
+	struct mnlu_gen_socket nlg;
+	struct vdpa_opts opts;
+	bool json_output;
+	struct indent_mem *indent;
+};
+
+static void pr_out_section_start(struct vdpa *vdpa, const char *name)
+{
+	open_json_object(NULL);
+	open_json_object(name);
+}
+
+static void pr_out_section_end(struct vdpa *vdpa)
+{
+	close_json_object();
+	close_json_object();
+}
+
+static void pr_out_array_start(struct vdpa *vdpa, const char *name)
+{
+	if (!vdpa->json_output) {
+		print_nl();
+		inc_indent(vdpa->indent);
+		print_indent(vdpa->indent);
+	}
+	open_json_array(PRINT_ANY, name);
+}
+
+static void pr_out_array_end(struct vdpa *vdpa)
+{
+	close_json_array(PRINT_JSON, NULL);
+	if (!vdpa->json_output)
+		dec_indent(vdpa->indent);
+}
+
+static const enum mnl_attr_data_type vdpa_policy[VDPA_ATTR_MAX + 1] = {
+	[VDPA_ATTR_MGMTDEV_BUS_NAME] = MNL_TYPE_NUL_STRING,
+	[VDPA_ATTR_MGMTDEV_DEV_NAME] = MNL_TYPE_NUL_STRING,
+	[VDPA_ATTR_DEV_NAME] = MNL_TYPE_STRING,
+	[VDPA_ATTR_DEV_ID] = MNL_TYPE_U32,
+	[VDPA_ATTR_DEV_VENDOR_ID] = MNL_TYPE_U32,
+	[VDPA_ATTR_DEV_MAX_VQS] = MNL_TYPE_U32,
+	[VDPA_ATTR_DEV_MAX_VQ_SIZE] = MNL_TYPE_U16,
+};
+
+static int attr_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type;
+
+	if (mnl_attr_type_valid(attr, VDPA_ATTR_MAX) < 0)
+		return MNL_CB_OK;
+
+	type = mnl_attr_get_type(attr);
+	if (mnl_attr_validate(attr, vdpa_policy[type]) < 0)
+		return MNL_CB_ERROR;
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int vdpa_argv_handle(struct vdpa *vdpa, int argc, char **argv,
+			    char **p_mdev_bus_name,
+			    char **p_mdev_name)
+{
+	unsigned int slashcount;
+	char *str;
+
+	if (argc <= 0 || *argv == NULL) {
+		fprintf(stderr,
+			"vdpa identification (\"mgmtdev_bus_name/mgmtdev_name\") expected\n");
+		return -EINVAL;
+	}
+	str = *argv;
+	slashcount = get_str_char_count(str, '/');
+	if (slashcount > 1) {
+		fprintf(stderr,
+			"Wrong vdpa mgmtdev identification string format\n");
+		fprintf(stderr, "Expected \"mgmtdev_bus_name/mgmtdev_name\"\n");
+		fprintf(stderr, "Expected \"mgmtdev_name\"\n");
+		return -EINVAL;
+	}
+	switch (slashcount) {
+	case 0:
+		*p_mdev_bus_name = NULL;
+		*p_mdev_name = str;
+		return 0;
+	case 1:
+		str_split_by_char(str, p_mdev_bus_name, p_mdev_name, '/');
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vdpa_argv_str(struct vdpa *vdpa, int argc, char **argv,
+			 const char **p_str)
+{
+	if (argc <= 0 || *argv == NULL) {
+		fprintf(stderr, "String parameter expected\n");
+		return -EINVAL;
+	}
+	*p_str = *argv;
+	return 0;
+}
+
+struct vdpa_args_metadata {
+	uint64_t o_flag;
+	const char *err_msg;
+};
+
+static const struct vdpa_args_metadata vdpa_args_required[] = {
+	{VDPA_OPT_VDEV_MGMTDEV_HANDLE, "management device handle not set."},
+	{VDPA_OPT_VDEV_NAME, "device name is not set."},
+	{VDPA_OPT_VDEV_HANDLE, "device name is not set."},
+};
+
+static int vdpa_args_finding_required_validate(uint64_t o_required,
+					       uint64_t o_found)
+{
+	uint64_t o_flag;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vdpa_args_required); i++) {
+		o_flag = vdpa_args_required[i].o_flag;
+		if ((o_required & o_flag) && !(o_found & o_flag)) {
+			fprintf(stderr, "%s\n", vdpa_args_required[i].err_msg);
+			return -EINVAL;
+		}
+	}
+	if (o_required & ~o_found) {
+		fprintf(stderr,
+			"BUG: unknown argument required but not found\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static void vdpa_opts_put(struct nlmsghdr *nlh, struct vdpa *vdpa)
+{
+	struct vdpa_opts *opts = &vdpa->opts;
+
+	if ((opts->present & VDPA_OPT_MGMTDEV_HANDLE) ||
+	    (opts->present & VDPA_OPT_VDEV_MGMTDEV_HANDLE)) {
+		if (opts->mdev_bus_name)
+			mnl_attr_put_strz(nlh, VDPA_ATTR_MGMTDEV_BUS_NAME,
+					  opts->mdev_bus_name);
+		mnl_attr_put_strz(nlh, VDPA_ATTR_MGMTDEV_DEV_NAME,
+				  opts->mdev_name);
+	}
+	if ((opts->present & VDPA_OPT_VDEV_NAME) ||
+	    (opts->present & VDPA_OPT_VDEV_HANDLE))
+		mnl_attr_put_strz(nlh, VDPA_ATTR_DEV_NAME, opts->vdev_name);
+}
+
+static int vdpa_argv_parse(struct vdpa *vdpa, int argc, char **argv,
+			   uint64_t o_required)
+{
+	struct vdpa_opts *opts = &vdpa->opts;
+	uint64_t o_all = o_required;
+	uint64_t o_found = 0;
+	int err;
+
+	if (o_required & VDPA_OPT_MGMTDEV_HANDLE) {
+		err = vdpa_argv_handle(vdpa, argc, argv, &opts->mdev_bus_name,
+				       &opts->mdev_name);
+		if (err)
+			return err;
+
+		NEXT_ARG_FWD();
+		o_found |= VDPA_OPT_MGMTDEV_HANDLE;
+	} else if (o_required & VDPA_OPT_VDEV_HANDLE) {
+		err = vdpa_argv_str(vdpa, argc, argv, &opts->vdev_name);
+		if (err)
+			return err;
+
+		NEXT_ARG_FWD();
+		o_found |= VDPA_OPT_VDEV_HANDLE;
+	}
+
+	while (NEXT_ARG_OK()) {
+		if ((matches(*argv, "name") == 0) &&
+		    (o_all & VDPA_OPT_VDEV_NAME)) {
+			const char *namestr;
+
+			NEXT_ARG_FWD();
+			err = vdpa_argv_str(vdpa, argc, argv, &namestr);
+			if (err)
+				return err;
+			opts->vdev_name = namestr;
+			NEXT_ARG_FWD();
+			o_found |= VDPA_OPT_VDEV_NAME;
+		} else if ((matches(*argv, "mgmtdev")  == 0) &&
+			   (o_all & VDPA_OPT_VDEV_MGMTDEV_HANDLE)) {
+			NEXT_ARG_FWD();
+			err = vdpa_argv_handle(vdpa, argc, argv,
+					       &opts->mdev_bus_name,
+					       &opts->mdev_name);
+			if (err)
+				return err;
+
+			NEXT_ARG_FWD();
+			o_found |= VDPA_OPT_VDEV_MGMTDEV_HANDLE;
+		} else {
+			fprintf(stderr, "Unknown option \"%s\"\n", *argv);
+			return -EINVAL;
+		}
+	}
+
+	opts->present = o_found;
+
+	return vdpa_args_finding_required_validate(o_required, o_found);
+}
+
+static int vdpa_argv_parse_put(struct nlmsghdr *nlh, struct vdpa *vdpa,
+			       int argc, char **argv,
+			       uint64_t o_required)
+{
+	int err;
+
+	err = vdpa_argv_parse(vdpa, argc, argv, o_required);
+	if (err)
+		return err;
+	vdpa_opts_put(nlh, vdpa);
+	return 0;
+}
+
+static void cmd_mgmtdev_help(void)
+{
+	fprintf(stderr, "Usage: vdpa mgmtdev show [ DEV ]\n");
+}
+
+static void pr_out_handle_start(struct vdpa *vdpa, struct nlattr **tb)
+{
+	const char *mdev_bus_name = NULL;
+	const char *mdev_name;
+	SPRINT_BUF(buf);
+
+	mdev_name = mnl_attr_get_str(tb[VDPA_ATTR_MGMTDEV_DEV_NAME]);
+	if (tb[VDPA_ATTR_MGMTDEV_BUS_NAME]) {
+		mdev_bus_name = mnl_attr_get_str(tb[VDPA_ATTR_MGMTDEV_BUS_NAME]);
+		sprintf(buf, "%s/%s", mdev_bus_name, mdev_name);
+	} else {
+		sprintf(buf, "%s", mdev_name);
+	}
+
+	if (vdpa->json_output)
+		open_json_object(buf);
+	else
+		printf("%s: ", buf);
+}
+
+static void pr_out_handle_end(struct vdpa *vdpa)
+{
+	if (vdpa->json_output)
+		close_json_object();
+	else
+		print_nl();
+}
+
+static void __pr_out_vdev_handle_start(struct vdpa *vdpa, const char *vdev_name)
+{
+	SPRINT_BUF(buf);
+
+	sprintf(buf, "%s", vdev_name);
+	if (vdpa->json_output)
+		open_json_object(buf);
+	else
+		printf("%s: ", buf);
+}
+
+static void pr_out_vdev_handle_start(struct vdpa *vdpa, struct nlattr **tb)
+{
+	const char *vdev_name;
+
+	vdev_name = mnl_attr_get_str(tb[VDPA_ATTR_DEV_NAME]);
+	__pr_out_vdev_handle_start(vdpa, vdev_name);
+}
+
+static void pr_out_vdev_handle_end(struct vdpa *vdpa)
+{
+	if (vdpa->json_output)
+		close_json_object();
+	else
+		print_nl();
+}
+
+static struct str_num_map class_map[] = {
+	{ .str = "net", .num = VIRTIO_ID_NET },
+	{ .str = "block", .num = VIRTIO_ID_BLOCK },
+	{ .str = NULL, },
+};
+
+static const char *parse_class(int num)
+{
+	const char *class;
+
+	class = str_map_lookup_uint(class_map, num);
+	return class ? class : "< unknown class >";
+}
+
+static void pr_out_mgmtdev_show(struct vdpa *vdpa, const struct nlmsghdr *nlh,
+				struct nlattr **tb)
+{
+	const char *class;
+	unsigned int i;
+
+	pr_out_handle_start(vdpa, tb);
+
+	if (tb[VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES]) {
+		uint64_t classes = mnl_attr_get_u64(tb[VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES]);
+
+		pr_out_array_start(vdpa, "supported_classes");
+
+		for (i = 1; i < 64; i++) {
+			if ((classes & (1ULL << i)) == 0)
+				continue;
+
+			class = parse_class(i);
+			print_string(PRINT_ANY, NULL, " %s", class);
+		}
+		pr_out_array_end(vdpa);
+	}
+
+	pr_out_handle_end(vdpa);
+}
+
+static int cmd_mgmtdev_show_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+	struct nlattr *tb[VDPA_ATTR_MAX + 1] = {};
+	struct vdpa *vdpa = data;
+
+	mnl_attr_parse(nlh, sizeof(*genl), attr_cb, tb);
+
+	if (!tb[VDPA_ATTR_MGMTDEV_DEV_NAME])
+		return MNL_CB_ERROR;
+
+	pr_out_mgmtdev_show(vdpa, nlh, tb);
+
+	return MNL_CB_OK;
+}
+
+static int cmd_mgmtdev_show(struct vdpa *vdpa, int argc, char **argv)
+{
+	uint16_t flags = NLM_F_REQUEST | NLM_F_ACK;
+	struct nlmsghdr *nlh;
+	int err;
+
+	if (argc == 0)
+		flags |= NLM_F_DUMP;
+
+	nlh = mnlu_gen_socket_cmd_prepare(&vdpa->nlg, VDPA_CMD_MGMTDEV_GET,
+					  flags);
+	if (argc > 0) {
+		err = vdpa_argv_parse_put(nlh, vdpa, argc, argv,
+					  VDPA_OPT_MGMTDEV_HANDLE);
+		if (err)
+			return err;
+	}
+
+	pr_out_section_start(vdpa, "mgmtdev");
+	err = mnlu_gen_socket_sndrcv(&vdpa->nlg, nlh, cmd_mgmtdev_show_cb, vdpa);
+	pr_out_section_end(vdpa);
+	return err;
+}
+
+static int cmd_mgmtdev(struct vdpa *vdpa, int argc, char **argv)
+{
+	if (!argc || matches(*argv, "help") == 0) {
+		cmd_mgmtdev_help();
+		return 0;
+	} else if (matches(*argv, "show") == 0 ||
+		   matches(*argv, "list") == 0) {
+		return cmd_mgmtdev_show(vdpa, argc - 1, argv + 1);
+	}
+	fprintf(stderr, "Command \"%s\" not found\n", *argv);
+	return -ENOENT;
+}
+
+static void cmd_dev_help(void)
+{
+	fprintf(stderr, "Usage: vdpa dev show [ DEV ]\n");
+	fprintf(stderr, "       vdpa dev add name NAME mgmtdev MANAGEMENTDEV\n");
+	fprintf(stderr, "       vdpa dev del DEV\n");
+}
+
+static const char *device_type_name(uint32_t type)
+{
+	switch (type) {
+	case 0x1: return "network";
+	case 0x2: return "block";
+	default: return "<unknown type>";
+	}
+}
+
+static void pr_out_dev(struct vdpa *vdpa, struct nlattr **tb)
+{
+	const char *mdev_name = mnl_attr_get_str(tb[VDPA_ATTR_MGMTDEV_DEV_NAME]);
+	uint32_t device_id = mnl_attr_get_u32(tb[VDPA_ATTR_DEV_ID]);
+	const char *mdev_bus_name = NULL;
+	char mgmtdev_buf[128];
+
+	if (tb[VDPA_ATTR_MGMTDEV_BUS_NAME])
+		mdev_bus_name = mnl_attr_get_str(tb[VDPA_ATTR_MGMTDEV_BUS_NAME]);
+
+	if (mdev_bus_name)
+		sprintf(mgmtdev_buf, "%s/%s", mdev_bus_name, mdev_name);
+	else
+		sprintf(mgmtdev_buf, "%s", mdev_name);
+	pr_out_vdev_handle_start(vdpa, tb);
+	print_string(PRINT_ANY, "type", "type %s", device_type_name(device_id));
+	print_string(PRINT_ANY, "mgmtdev", " mgmtdev %s", mgmtdev_buf);
+
+	if (tb[VDPA_ATTR_DEV_VENDOR_ID])
+		print_uint(PRINT_ANY, "vendor_id", " vendor_id %u",
+			   mnl_attr_get_u32(tb[VDPA_ATTR_DEV_VENDOR_ID]));
+	if (tb[VDPA_ATTR_DEV_MAX_VQS])
+		print_uint(PRINT_ANY, "max_vqs", " max_vqs %u",
+			   mnl_attr_get_u32(tb[VDPA_ATTR_DEV_MAX_VQS]));
+	if (tb[VDPA_ATTR_DEV_MAX_VQ_SIZE])
+		print_uint(PRINT_ANY, "max_vq_size", " max_vq_size %u",
+			   mnl_attr_get_u16(tb[VDPA_ATTR_DEV_MAX_VQ_SIZE]));
+	pr_out_vdev_handle_end(vdpa);
+}
+
+static int cmd_dev_show_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+	struct nlattr *tb[VDPA_ATTR_MAX + 1] = {};
+	struct vdpa *vdpa = data;
+
+	mnl_attr_parse(nlh, sizeof(*genl), attr_cb, tb);
+	if (!tb[VDPA_ATTR_MGMTDEV_DEV_NAME] ||
+	    !tb[VDPA_ATTR_DEV_NAME] || !tb[VDPA_ATTR_DEV_ID])
+		return MNL_CB_ERROR;
+	pr_out_dev(vdpa, tb);
+	return MNL_CB_OK;
+}
+
+static int cmd_dev_show(struct vdpa *vdpa, int argc, char **argv)
+{
+	uint16_t flags = NLM_F_REQUEST | NLM_F_ACK;
+	struct nlmsghdr *nlh;
+	int err;
+
+	if (argc <= 0)
+		flags |= NLM_F_DUMP;
+
+	nlh = mnlu_gen_socket_cmd_prepare(&vdpa->nlg, VDPA_CMD_DEV_GET, flags);
+	if (argc > 0) {
+		err = vdpa_argv_parse_put(nlh, vdpa, argc, argv,
+					  VDPA_OPT_VDEV_HANDLE);
+		if (err)
+			return err;
+	}
+
+	pr_out_section_start(vdpa, "dev");
+	err = mnlu_gen_socket_sndrcv(&vdpa->nlg, nlh, cmd_dev_show_cb, vdpa);
+	pr_out_section_end(vdpa);
+	return err;
+}
+
+static int cmd_dev_add(struct vdpa *vdpa, int argc, char **argv)
+{
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = mnlu_gen_socket_cmd_prepare(&vdpa->nlg, VDPA_CMD_DEV_NEW,
+					  NLM_F_REQUEST | NLM_F_ACK);
+	err = vdpa_argv_parse_put(nlh, vdpa, argc, argv,
+				  VDPA_OPT_VDEV_MGMTDEV_HANDLE | VDPA_OPT_VDEV_NAME);
+	if (err)
+		return err;
+
+	return mnlu_gen_socket_sndrcv(&vdpa->nlg, nlh, NULL, NULL);
+}
+
+static int cmd_dev_del(struct vdpa *vdpa,  int argc, char **argv)
+{
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = mnlu_gen_socket_cmd_prepare(&vdpa->nlg, VDPA_CMD_DEV_DEL,
+					  NLM_F_REQUEST | NLM_F_ACK);
+	err = vdpa_argv_parse_put(nlh, vdpa, argc, argv, VDPA_OPT_VDEV_HANDLE);
+	if (err)
+		return err;
+
+	return mnlu_gen_socket_sndrcv(&vdpa->nlg, nlh, NULL, NULL);
+}
+
+static int cmd_dev(struct vdpa *vdpa, int argc, char **argv)
+{
+	if (!argc)
+		return cmd_dev_show(vdpa, argc - 1, argv + 1);
+
+	if (matches(*argv, "help") == 0) {
+		cmd_dev_help();
+		return 0;
+	} else if (matches(*argv, "show") == 0 ||
+		   matches(*argv, "list") == 0) {
+		return cmd_dev_show(vdpa, argc - 1, argv + 1);
+	} else if (matches(*argv, "add") == 0) {
+		return cmd_dev_add(vdpa, argc - 1, argv + 1);
+	} else if (matches(*argv, "del") == 0) {
+		return cmd_dev_del(vdpa, argc - 1, argv + 1);
+	}
+	fprintf(stderr, "Command \"%s\" not found\n", *argv);
+	return -ENOENT;
+}
+
+static void help(void)
+{
+	fprintf(stderr,
+		"Usage: vdpa [ OPTIONS ] OBJECT { COMMAND | help }\n"
+		"where  OBJECT := { mgmtdev | dev }\n"
+		"       OPTIONS := { -V[ersion] | -n[o-nice-names] | -j[son] | -p[retty] | -v[erbose] }\n");
+}
+
+static int vdpa_cmd(struct vdpa *vdpa, int argc, char **argv)
+{
+	if (!argc || matches(*argv, "help") == 0) {
+		help();
+		return 0;
+	} else if (matches(*argv, "mgmtdev") == 0) {
+		return cmd_mgmtdev(vdpa, argc - 1, argv + 1);
+	} else if (matches(*argv, "dev") == 0) {
+		return cmd_dev(vdpa, argc - 1, argv + 1);
+	}
+	fprintf(stderr, "Object \"%s\" not found\n", *argv);
+	return -ENOENT;
+}
+
+static int vdpa_init(struct vdpa *vdpa)
+{
+	int err;
+
+	err = mnlu_gen_socket_open(&vdpa->nlg, VDPA_GENL_NAME,
+				   VDPA_GENL_VERSION);
+	if (err) {
+		fprintf(stderr, "Failed to connect to vdpa Netlink\n");
+		return -errno;
+	}
+	new_json_obj_plain(vdpa->json_output);
+	return 0;
+}
+
+static void vdpa_fini(struct vdpa *vdpa)
+{
+	delete_json_obj_plain();
+	mnlu_gen_socket_close(&vdpa->nlg);
+}
+
+static struct vdpa *vdpa_alloc(void)
+{
+	struct vdpa *vdpa = calloc(1, sizeof(struct vdpa));
+
+	if (!vdpa)
+		return NULL;
+
+	vdpa->indent = alloc_indent_mem();
+	if (!vdpa->indent)
+		goto indent_err;
+
+	return vdpa;
+
+indent_err:
+	free(vdpa);
+	return NULL;
+}
+
+static void vdpa_free(struct vdpa *vdpa)
+{
+	free_indent_mem(vdpa->indent);
+	free(vdpa);
+}
+
+int main(int argc, char **argv)
+{
+	static const struct option long_options[] = {
+		{ "Version",		no_argument,	NULL, 'V' },
+		{ "json",		no_argument,	NULL, 'j' },
+		{ "pretty",		no_argument,	NULL, 'p' },
+		{ "help",		no_argument,	NULL, 'h' },
+		{ NULL, 0, NULL, 0 }
+	};
+	struct vdpa *vdpa;
+	int opt;
+	int err;
+	int ret;
+
+	vdpa = vdpa_alloc();
+	if (!vdpa) {
+		fprintf(stderr, "Failed to allocate memory for vdpa\n");
+		return EXIT_FAILURE;
+	}
+
+	while ((opt = getopt_long(argc, argv, "Vjpsh", long_options, NULL)) >= 0) {
+		switch (opt) {
+		case 'V':
+			printf("vdpa utility, iproute2-%s\n", version);
+			ret = EXIT_SUCCESS;
+			goto vdpa_free;
+		case 'j':
+			vdpa->json_output = true;
+			break;
+		case 'p':
+			pretty = true;
+			break;
+		case 'h':
+			help();
+			ret = EXIT_SUCCESS;
+			goto vdpa_free;
+		default:
+			fprintf(stderr, "Unknown option.\n");
+			help();
+			ret = EXIT_FAILURE;
+			goto vdpa_free;
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	err = vdpa_init(vdpa);
+	if (err) {
+		ret = EXIT_FAILURE;
+		goto vdpa_free;
+	}
+
+	err = vdpa_cmd(vdpa, argc, argv);
+	if (err) {
+		ret = EXIT_FAILURE;
+		goto vdpa_fini;
+	}
+
+	ret = EXIT_SUCCESS;
+
+vdpa_fini:
+	vdpa_fini(vdpa);
+vdpa_free:
+	vdpa_free(vdpa);
+	return ret;
+}
-- 
2.26.2

Re: [PATCH iproute2-next v5 0/5] Add vdpa device management tool

[David Ahern]

On 2/10/21 11:34 AM, Parav Pandit wrote:
> Linux vdpa interface allows vdpa device management functionality.
> This includes adding, removing, querying vdpa devices.
> 
> vdpa interface also includes showing supported management devices
> which support such operations.
> 
> This patchset includes kernel uapi headers and a vdpa tool.
> 

applied to iproute2-next.

I am expecting a followup converting devlink to use the indent and mnl
helpers.

RE: [PATCH iproute2-next v5 0/5] Add vdpa device management tool

[Parav Pandit]

> From: David Ahern <dsahern@gmail.com>
> Sent: Thursday, February 11, 2021 9:50 PM
> 
> On 2/10/21 11:34 AM, Parav Pandit wrote:
> > Linux vdpa interface allows vdpa device management functionality.
> > This includes adding, removing, querying vdpa devices.
> >
> > vdpa interface also includes showing supported management devices
> > which support such operations.
> >
> > This patchset includes kernel uapi headers and a vdpa tool.
> >
> 
> applied to iproute2-next.
> 
> I am expecting a followup converting devlink to use the indent and mnl
> helpers.
Yes. Thanks David. 
I will finish internal review next week and more test to bring here.