From: Viresh Kumar <viresh.kumar@linaro.org>
To: qemu-devel@nongnu.org, Viresh Kumar <viresh.kumar@linaro.org>
Cc: "Vincent Guittot" <vincent.guittot@linaro.org>,
"Jie Deng" <jie.deng@intel.com>,
"Bill Mills" <bill.mills@linaro.org>,
"Arnd Bergmann" <arnd.bergmann@linaro.com>,
"Mike Holmes" <mike.holmes@linaro.org>,
"Alex Bennée" <alex.bennee@linaro.org>,
stratos-dev@op-lists.linaro.org
Subject: [PATCH V2.1 4/6] tools/vhost-user-i2c: Add backend driver
Date: Mon, 5 Apr 2021 15:08:15 +0530 [thread overview]
Message-ID: <cc3560b392efb6ac04a35be34ef0e4dcf0026a28.1617614056.git.viresh.kumar@linaro.org> (raw)
In-Reply-To: <e0adcd9552cee4de0ee844f6b3c87fb2b2f2357c.1617278395.git.viresh.kumar@linaro.org>
This adds the vhost-user backend driver to support virtio based I2C and
SMBUS devices.
vhost-user-i2c --help
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
V2->2.1
- Check for more smbus functionalities.
- Use better glibc helpers for string parsing.
- Remove code to check return value of memory allocation.
- Elaborate a comment.
- Minor update to meson.build
tools/meson.build | 8 +
tools/vhost-user-i2c/50-qemu-i2c.json.in | 5 +
tools/vhost-user-i2c/main.c | 800 +++++++++++++++++++++++
tools/vhost-user-i2c/meson.build | 10 +
4 files changed, 823 insertions(+)
create mode 100644 tools/vhost-user-i2c/50-qemu-i2c.json.in
create mode 100644 tools/vhost-user-i2c/main.c
create mode 100644 tools/vhost-user-i2c/meson.build
diff --git a/tools/meson.build b/tools/meson.build
index 3e5a0abfa29f..8271e110978b 100644
--- a/tools/meson.build
+++ b/tools/meson.build
@@ -24,3 +24,11 @@ endif
if have_virtiofsd
subdir('virtiofsd')
endif
+
+have_virtioi2c= (have_system and
+ have_tools and
+ 'CONFIG_LINUX' in config_host)
+
+if have_virtioi2c
+ subdir('vhost-user-i2c')
+endif
diff --git a/tools/vhost-user-i2c/50-qemu-i2c.json.in b/tools/vhost-user-i2c/50-qemu-i2c.json.in
new file mode 100644
index 000000000000..dafd1337fa9c
--- /dev/null
+++ b/tools/vhost-user-i2c/50-qemu-i2c.json.in
@@ -0,0 +1,5 @@
+{
+ "description": "QEMU vhost-user-i2c",
+ "type": "bridge",
+ "binary": "@libexecdir@/vhost-user-i2c"
+}
diff --git a/tools/vhost-user-i2c/main.c b/tools/vhost-user-i2c/main.c
new file mode 100644
index 000000000000..b9c7f729e882
--- /dev/null
+++ b/tools/vhost-user-i2c/main.c
@@ -0,0 +1,800 @@
+/*
+ * VIRTIO I2C Emulation via vhost-user
+ *
+ * Copyright (c) 2021 Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#define G_LOG_DOMAIN "vhost-user-i2c"
+#define G_LOG_USE_STRUCTURED 1
+
+#include <assert.h>
+#include <endian.h>
+#include <fcntl.h>
+#include <gio/gio.h>
+#include <gio/gunixsocketaddress.h>
+#include <glib.h>
+#include <glib-unix.h>
+#include <glib/gstdio.h>
+#include <inttypes.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "qemu/compiler.h"
+#include "qemu/cutils.h"
+#include "standard-headers/linux/virtio_i2c.h"
+#include "subprojects/libvhost-user/libvhost-user-glib.h"
+#include "subprojects/libvhost-user/libvhost-user.h"
+
+#define VHOST_USER_I2C_MAX_QUEUES 1
+
+/* vhost-user-i2c definitions */
+
+#define MAX_I2C_VDEV (1 << 7)
+#define MAX_I2C_ADAPTER 16
+
+typedef struct {
+ int32_t fd;
+ int32_t bus;
+ bool smbus;
+ bool clients[MAX_I2C_VDEV];
+} VI2cAdapter;
+
+typedef struct {
+ VugDev dev;
+ GMainLoop *loop;
+ VI2cAdapter *adapter[MAX_I2C_ADAPTER];
+ uint16_t adapter_map[MAX_I2C_VDEV];
+ uint32_t adapter_num;
+} VuI2c;
+
+static gboolean print_cap, verbose;
+static gchar *socket_path, *device_list;
+static gint socket_fd = -1;
+
+static GOptionEntry options[] = {
+ { "socket-path", 's', 0, G_OPTION_ARG_FILENAME, &socket_path,
+ "Location of vhost-user Unix domain socket, incompatible with --fd",
+ "PATH" },
+ { "fd", 'f', 0, G_OPTION_ARG_INT, &socket_fd,
+ "Specify file-descriptor of the backend, don't use with --socket-path",
+ "FD" },
+ { "device-list", 'l', 0, G_OPTION_ARG_STRING, &device_list,
+ "List of i2c-dev bus and attached devices", "I2C Devices" },
+ { "print-capabilities", 'c', 0, G_OPTION_ARG_NONE, &print_cap,
+ "Output to stdout the backend capabilities in JSON format and exit",
+ NULL},
+ { "verbose", 'v', 0, G_OPTION_ARG_NONE, &verbose,
+ "Be more verbose in output", NULL},
+ { NULL }
+};
+
+
+/* I2c helpers */
+static void fmt_bytes(GString *s, uint8_t *bytes, int len)
+{
+ int32_t i;
+ for (i = 0; i < len; i++) {
+ if (i && i % 16 == 0) {
+ g_string_append_c(s, '\n');
+ }
+ g_string_append_printf(s, "%x ", bytes[i]);
+ }
+}
+
+static void vi2c_dump_msg(struct i2c_msg *msgs, size_t count)
+{
+ int32_t i;
+
+ for (i = 0; i < count; i++) {
+ g_autoptr(GString) s = g_string_new("\nI2c request: ");
+
+ g_string_append_printf(s, "addr: %x\n", msgs[i].addr);
+ g_string_append_printf(s, "transfer len: %x\n", msgs[i].len);
+
+ g_string_append_printf(s, "%s: ", msgs[i].flags & I2C_M_RD ?
+ "Data read" : "Data Written");
+ fmt_bytes(s, (uint8_t *)msgs[i].buf, msgs[i].len);
+ g_string_append_printf(s, "\n");
+
+ g_debug("%s: %s", __func__, s->str);
+ }
+}
+
+static int vi2c_map_adapters(VuI2c *i2c)
+{
+ VI2cAdapter *adapter;
+ int32_t i, client_addr;
+
+ /*
+ * Flatten the map for client address and adapter to the array:
+ *
+ * adapter_map[MAX_I2C_VDEV]:
+ *
+ * Adapter | adapter2 | none | adapter1 | adapter3 | none| (val)
+ * |----------|-------|----------|----------|-----|
+ * Slave Address | addr 1 | none | addr 2 | addr 3 | none| (idx)
+ * |<-----------------------MAX_I2C_VDEV---------------->|
+ */
+ for (i = 0; i < i2c->adapter_num; i++) {
+ adapter = i2c->adapter[i];
+
+ for (client_addr = 0; client_addr < MAX_I2C_VDEV; client_addr++) {
+ if (adapter->clients[client_addr]) {
+ if (i2c->adapter_map[client_addr]) {
+ g_printerr("client addr %x repeated, not supported!\n",
+ client_addr);
+ return -1;
+ }
+
+ /* The array is initialized to 0, + 1 for index */
+ i2c->adapter_map[client_addr] = i + 1;
+ if (verbose) {
+ g_print("client: 0x%x -> i2c adapter: %d\n", client_addr,
+ adapter->bus);
+ }
+ }
+ }
+ }
+ return 0;
+}
+
+static VI2cAdapter *vi2c_find_adapter(VuI2c *i2c, uint16_t addr)
+{
+ if (addr < MAX_I2C_VDEV && (i2c->adapter_map[addr] != 0)) {
+ return i2c->adapter[i2c->adapter_map[addr] - 1];
+ }
+
+ return NULL;
+}
+
+static bool vi2c_set_client_addr(VI2cAdapter *adapter, uint16_t addr)
+{
+ if (ioctl(adapter->fd, I2C_SLAVE, addr) < 0) {
+ if (errno == EBUSY) {
+ g_printerr("client device %x is busy!\n", addr);
+ } else {
+ g_printerr("client device %d does not exist!\n", addr);
+ }
+ return false;
+ }
+ return true;
+}
+
+static void vi2c_remove_adapters(VuI2c *i2c)
+{
+ VI2cAdapter *adapter;
+ int32_t i;
+
+ for (i = 0; i < MAX_I2C_ADAPTER; i++) {
+ adapter = i2c->adapter[i];
+ if (!adapter) {
+ break;
+ }
+
+ if (adapter->fd > 0) {
+ close(adapter->fd);
+ }
+
+ g_free(adapter);
+ i2c->adapter[i] = NULL;
+ }
+}
+
+static VI2cAdapter *vi2c_create_adapter(int32_t bus, uint16_t client_addr[],
+ int32_t n_client)
+{
+ g_autofree VI2cAdapter *adapter = NULL;
+ g_autofree char *path = NULL;
+ uint64_t funcs;
+ int32_t fd, i;
+
+ if (bus < 0) {
+ return NULL;
+ }
+
+ adapter = g_malloc0(sizeof(*adapter));
+ path = g_strdup_printf("/dev/i2c-%d", bus);
+
+ fd = open(path, O_RDWR);
+ if (fd < 0) {
+ g_printerr("virtio_i2c: failed to open %s\n", path);
+ return NULL;
+ }
+
+ adapter->fd = fd;
+ adapter->bus = bus;
+
+ if (ioctl(fd, I2C_FUNCS, &funcs) < 0) {
+ g_printerr("virtio_i2c: failed to get functionality %s: %d\n", path,
+ errno);
+ goto close_fd;
+ }
+
+ if (funcs & I2C_FUNC_I2C) {
+ adapter->smbus = false;
+ } else if (funcs & (I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA)) {
+ adapter->smbus = true;
+ } else {
+ g_printerr("virtio_i2c: invalid functionality %lx\n", funcs);
+ goto close_fd;
+ }
+
+ for (i = 0; i < n_client; i++) {
+ if (client_addr[i]) {
+ if (!vi2c_set_client_addr(adapter, client_addr[i])) {
+ goto close_fd;
+ }
+
+ if (adapter->clients[client_addr[i]]) {
+ g_printerr("client addr 0x%x repeat, not allowed.\n",
+ client_addr[i]);
+ goto close_fd;
+ }
+
+ adapter->clients[client_addr[i]] = true;
+ if (verbose) {
+ g_print("Added client 0x%x to bus %u\n", client_addr[i], bus);
+ }
+ }
+ }
+
+ if (verbose) {
+ g_print("Added adapter: bus: %d, func %s\n", bus,
+ adapter->smbus ? "smbus" : "i2c");
+ }
+ return g_steal_pointer(&adapter);
+
+close_fd:
+ close(fd);
+ return NULL;
+}
+
+/*
+ * Virtio I2C device list format.
+ *
+ * <bus>:<client_addr>[:<client_addr>],
+ * [<bus>:<client_addr>[:<client_addr>]]
+ *
+ * bus (dec): adatper bus number.
+ * e.g. 2 for /dev/i2c-2
+ * client_addr (hex): address for client device
+ * e.g. 0x1C or 1C
+ *
+ * Example: --device-list="2:0x1c:0x20,3:0x10:0x2c"
+ *
+ * Note: client address can not repeat.
+ */
+static int32_t vi2c_parse(VuI2c *i2c)
+{
+ uint16_t client_addr[MAX_I2C_VDEV];
+ int32_t n_adapter = 0, n_client, i, j;
+ int64_t addr, bus;
+ gchar **cp, **dev;
+
+ cp = g_strsplit(device_list, ",", 0);
+
+ /* Read <bus>:<client_addr>[:<client_addr>] entries one by one */
+ for (i = 0; cp[i] && *cp[i] != '\0'; i++) {
+ if (n_adapter == MAX_I2C_ADAPTER) {
+ g_printerr("too many adapter (%d), only support %d\n", n_adapter,
+ MAX_I2C_ADAPTER);
+ goto out;
+ }
+
+ dev = g_strsplit(cp[i], ":", 0);
+
+ if (qemu_strtol(dev[0], NULL, 10, &bus) || bus < 0) {
+ g_printerr("Invalid bus number %s\n", dev[0]);
+ goto out;
+ }
+
+ /* Parse clients <client_addr>[:<client_addr>] entries one by one */
+ for (n_client = 0, j = 1; dev[j] && *dev[j] != '\0'; j++) {
+ if (n_client == MAX_I2C_VDEV) {
+ g_printerr("too many devices (%d), only support %d\n",
+ n_client, MAX_I2C_VDEV);
+ g_strfreev(dev);
+ goto out;
+ }
+
+ if (qemu_strtol(dev[j], NULL, 16, &addr) ||
+ addr < 0 || addr > MAX_I2C_VDEV) {
+ g_printerr("Invalid address %s : %lx\n", dev[j], addr);
+ g_strfreev(dev);
+ goto out;
+ }
+
+ client_addr[n_client++] = addr;
+ if (verbose) {
+ g_print("i2c adapter %ld:0x%lx\n", bus, addr);
+ }
+ }
+ g_strfreev(dev);
+
+ i2c->adapter[n_adapter] = vi2c_create_adapter(bus, client_addr,
+ n_client);
+ if (!i2c->adapter[n_adapter]) {
+ goto out;
+ }
+
+ n_adapter++;
+ }
+ g_strfreev(cp);
+
+ if (!n_adapter) {
+ g_printerr("Failed to add any adapters\n");
+ return -1;
+ }
+
+ i2c->adapter_num = n_adapter;
+
+ if (!vi2c_map_adapters(i2c)) {
+ return 0;
+ }
+
+out:
+ g_strfreev(cp);
+ vi2c_remove_adapters(i2c);
+ return -1;
+}
+
+static int32_t i2c_xfer(VI2cAdapter *adapter, struct i2c_msg *msgs,
+ size_t count)
+{
+ struct i2c_rdwr_ioctl_data data;
+
+ data.nmsgs = count;
+ data.msgs = msgs;
+
+ return ioctl(adapter->fd, I2C_RDWR, &data);
+}
+
+/*
+ * Based on Linux's drivers/i2c/i2c-core-smbus.c:i2c_smbus_xfer_emulated(). This
+ * function tries to reverse what Linux does, only support basic modes (up to
+ * word transfer).
+ */
+static int32_t smbus_xfer(VI2cAdapter *adapter, struct i2c_msg *msgs,
+ size_t count)
+{
+ union i2c_smbus_data data;
+ struct i2c_smbus_ioctl_data smbus_data = { .data = &data };
+ int32_t ret;
+
+ smbus_data.command = msgs[0].buf[0];
+
+ switch (count) {
+ case 1:
+ if (msgs[0].flags & I2C_M_RD) {
+ if (msgs[0].len > 1) {
+ g_printerr("Incorrect message length for read operation: %d\n",
+ msgs[0].len);
+ return -1;
+ }
+ smbus_data.read_write = I2C_SMBUS_READ;
+ } else {
+ smbus_data.read_write = I2C_SMBUS_WRITE;
+ }
+
+ if (!msgs[0].len) {
+ smbus_data.size = I2C_SMBUS_QUICK;
+ smbus_data.data = NULL;
+ } else if (msgs[0].len == 1) {
+ smbus_data.size = I2C_SMBUS_BYTE;
+ if (smbus_data.read_write == I2C_SMBUS_WRITE) {
+ smbus_data.data = NULL;
+ }
+ } else if (msgs[0].len == 2) {
+ smbus_data.size = I2C_SMBUS_BYTE_DATA;
+ data.byte = msgs[0].buf[1];
+ } else if (msgs[0].len == 3) {
+ smbus_data.size = I2C_SMBUS_WORD_DATA;
+ data.word = msgs[0].buf[1] | (msgs[0].buf[2] << 8);
+ } else {
+ g_printerr("Message length not supported for write operation: %d\n",
+ msgs[0].len);
+ return -1;
+ }
+
+ break;
+ case 2:
+ if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD) ||
+ (msgs[0].len != 1) || (msgs[1].len > 2)) {
+ g_printerr("Expecting a valid read smbus transfer: %ld: %d: %d\n",
+ count, msgs[0].len, msgs[1].len);
+ return -1;
+ }
+
+ smbus_data.read_write = I2C_SMBUS_READ;
+ smbus_data.size = msgs[1].len == 1 ?
+ I2C_SMBUS_BYTE_DATA : I2C_SMBUS_WORD_DATA;
+ break;
+ default:
+ g_printerr("Invalid number of messages for smbus xfer: %ld\n", count);
+ return -1;
+ }
+
+ if (verbose) {
+ g_print("SMBUS command: %x: %x: %x\n", smbus_data.read_write,
+ smbus_data.command, smbus_data.size);
+ }
+
+ ret = ioctl(adapter->fd, I2C_SMBUS, &smbus_data);
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (smbus_data.read_write == I2C_SMBUS_WRITE) {
+ return 0;
+ }
+
+ switch (smbus_data.size) {
+ case I2C_SMBUS_BYTE:
+ msgs[0].buf[0] = data.byte;
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ msgs[1].buf[0] = data.byte;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ msgs[1].buf[0] = data.word & 0xff;
+ msgs[1].buf[1] = data.word >> 8;
+ break;
+ }
+
+ return 0;
+}
+
+static uint8_t vi2c_xfer(VuDev *dev, struct i2c_msg *msgs, size_t count)
+{
+ VuI2c *i2c = container_of(dev, VuI2c, dev.parent);
+ VI2cAdapter *adapter;
+ int8_t ret;
+
+ /* Assume that adapter should be same for all messages sent together */
+ adapter = vi2c_find_adapter(i2c, msgs[0].addr);
+ if (!adapter) {
+ g_printerr("Failed to find adapter for address: %x\n", msgs[0].addr);
+ return VIRTIO_I2C_MSG_ERR;
+ }
+
+ /* Set client's address */
+ if (!vi2c_set_client_addr(adapter, msgs[0].addr)) {
+ return VIRTIO_I2C_MSG_ERR;
+ }
+
+ if (adapter->smbus) {
+ ret = smbus_xfer(adapter, msgs, count);
+ } else {
+ ret = i2c_xfer(adapter, msgs, count);
+ }
+
+ if (ret < 0) {
+ g_printerr("Failed to transfer data to address %x : %d\n",
+ msgs[0].addr, errno);
+ return VIRTIO_I2C_MSG_ERR;
+ }
+
+ if (verbose) {
+ vi2c_dump_msg(msgs, count);
+ }
+
+ return VIRTIO_I2C_MSG_OK;
+}
+
+/* Virtio helpers */
+static uint64_t vi2c_get_features(VuDev *dev)
+{
+ if (verbose) {
+ g_info("%s: replying", __func__);
+ }
+ return 0;
+}
+
+static void vi2c_set_features(VuDev *dev, uint64_t features)
+{
+ if (verbose && features) {
+ g_autoptr(GString) s = g_string_new("Requested un-handled feature");
+ g_string_append_printf(s, " 0x%" PRIx64 "", features);
+ g_info("%s: %s", __func__, s->str);
+ }
+}
+
+static void vi2c_handle_ctrl(VuDev *dev, int qidx)
+{
+ VuVirtq *vq = vu_get_queue(dev, qidx);
+ struct virtio_i2c_out_hdr *out_hdr;
+ size_t i, count = 0, len, in_hdr_len;
+ struct i2c_msg *msgs;
+ VuVirtqElement *elem;
+ uint8_t status;
+ struct {
+ struct virtio_i2c_in_hdr *in_hdr;
+ VuVirtqElement *elem;
+ size_t size;
+ } *info;
+
+ /*
+ * Count number of messages.
+ *
+ * We don't necessarily need to do this for transfers with I2C masters, but
+ * for SMBUS transfers, where is single read operation can come in two
+ * different virtio messages.
+ *
+ * Otherwise too for the I2C transfers, it optimizes the transfers anyway as
+ * we don't need to call the ioctl again and again.
+ */
+ do {
+ elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
+ } while (elem && ++count);
+
+ if (!count) {
+ if (verbose) {
+ g_printerr("Virtqueue can't have 0 elements\n");
+ }
+ return;
+ }
+
+ /* Rewind everything, now that we have counted the number of messages */
+ vu_queue_rewind(dev, vq, count);
+
+ if (verbose) {
+ g_print("Received %ld messages in virtqueue\n", count);
+ }
+
+ /* Allocate memory for msgs and info */
+ msgs = g_malloc0_n(count, sizeof(*msgs) + sizeof(*info));
+ info = (void *)(msgs + count);
+
+ for (i = 0; i < count; i++) {
+ elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
+ assert(elem);
+
+ info[i].elem = elem;
+ info[i].size = sizeof(*info[i].in_hdr);
+
+ g_debug("%s: got queue (in %d, out %d)", __func__, elem->in_num,
+ elem->out_num);
+
+ /* Validate size of "out" header */
+ if (elem->out_sg[0].iov_len != sizeof(*out_hdr)) {
+ g_warning("%s: Invalid out hdr %zu : %zu\n", __func__,
+ elem->out_sg[0].iov_len, sizeof(*out_hdr));
+ goto out;
+ }
+
+ out_hdr = elem->out_sg[0].iov_base;
+
+ /* Bit 0 is reserved in virtio spec */
+ msgs[i].addr = le16toh(out_hdr->addr) >> 1;
+
+ /* Read Operation */
+ if (elem->out_num == 1 && elem->in_num == 2) {
+ len = elem->in_sg[0].iov_len;
+ if (!len) {
+ g_warning("%s: Read buffer length can't be zero\n", __func__);
+ goto out;
+ }
+
+ msgs[i].buf = elem->in_sg[0].iov_base;
+ msgs[i].flags = I2C_M_RD;
+ msgs[i].len = len;
+
+ info[i].in_hdr = elem->in_sg[1].iov_base;
+ info[i].size += len;
+ in_hdr_len = elem->in_sg[1].iov_len;
+ } else if (elem->out_num == 2 && elem->in_num == 1) {
+ /* Write Operation */
+ len = elem->out_sg[1].iov_len;
+ if (!len) {
+ g_warning("%s: Write buffer length can't be zero\n", __func__);
+ goto out;
+ }
+
+ msgs[i].buf = elem->out_sg[1].iov_base;
+ msgs[i].flags = 0;
+ msgs[i].len = len;
+
+ info[i].in_hdr = elem->in_sg[0].iov_base;
+ in_hdr_len = elem->in_sg[0].iov_len;
+ } else {
+ g_warning("%s: Transfer type not supported (in %d, out %d)\n",
+ __func__, elem->in_num, elem->out_num);
+ goto out;
+ }
+
+ /* Validate size of "in" header */
+ if (in_hdr_len != sizeof(*(info[i].in_hdr))) {
+ g_warning("%s: Invalid in hdr %zu : %zu\n", __func__, in_hdr_len,
+ sizeof(*(info[i].in_hdr)));
+ goto out;
+ }
+ }
+
+ status = vi2c_xfer(dev, msgs, count);
+
+ for (i = 0; i < count; i++) {
+ info[i].in_hdr->status = status;
+ vu_queue_push(dev, vq, info[i].elem, info[i].size);
+ }
+
+ vu_queue_notify(dev, vq);
+
+out:
+ g_free(msgs);
+}
+
+static void
+vi2c_queue_set_started(VuDev *dev, int qidx, bool started)
+{
+ VuVirtq *vq = vu_get_queue(dev, qidx);
+
+ g_debug("queue started %d:%d\n", qidx, started);
+
+ if (!qidx) {
+ vu_set_queue_handler(dev, vq, started ? vi2c_handle_ctrl : NULL);
+ }
+}
+
+/*
+ * vi2c_process_msg: process messages of vhost-user interface
+ *
+ * Any that are not handled here are processed by the libvhost library
+ * itself.
+ */
+static int vi2c_process_msg(VuDev *dev, VhostUserMsg *msg, int *do_reply)
+{
+ VuI2c *i2c = container_of(dev, VuI2c, dev.parent);
+
+ if (msg->request == VHOST_USER_NONE) {
+ g_main_loop_quit(i2c->loop);
+ return 1;
+ }
+
+ return 0;
+}
+
+static const VuDevIface vuiface = {
+ .set_features = vi2c_set_features,
+ .get_features = vi2c_get_features,
+ .queue_set_started = vi2c_queue_set_started,
+ .process_msg = vi2c_process_msg,
+};
+
+static gboolean hangup(gpointer user_data)
+{
+ GMainLoop *loop = (GMainLoop *) user_data;
+ g_info("%s: caught hangup/quit signal, quitting main loop", __func__);
+ g_main_loop_quit(loop);
+ return true;
+}
+
+static void vi2c_panic(VuDev *dev, const char *msg)
+{
+ g_critical("%s\n", msg);
+ exit(EXIT_FAILURE);
+}
+
+/* Print vhost-user.json backend program capabilities */
+static void print_capabilities(void)
+{
+ printf("{\n");
+ printf(" \"type\": \"i2c\"\n");
+ printf(" \"device-list\"\n");
+ printf("}\n");
+}
+
+static void vi2c_destroy(VuI2c *i2c)
+{
+ vi2c_remove_adapters(i2c);
+ vug_deinit(&i2c->dev);
+ if (socket_path) {
+ unlink(socket_path);
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ GError *error = NULL;
+ GOptionContext *context;
+ g_autoptr(GSocket) socket = NULL;
+ VuI2c i2c = {0};
+
+ context = g_option_context_new("vhost-user emulation of I2C device");
+ g_option_context_add_main_entries(context, options, "vhost-user-i2c");
+ if (!g_option_context_parse(context, &argc, &argv, &error)) {
+ g_printerr("option parsing failed: %s\n", error->message);
+ exit(1);
+ }
+
+ if (print_cap) {
+ print_capabilities();
+ exit(0);
+ }
+
+ if (!socket_path && socket_fd < 0) {
+ g_printerr("Please specify either --fd or --socket-path\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (verbose) {
+ g_log_set_handler(NULL, G_LOG_LEVEL_MASK, g_log_default_handler, NULL);
+ g_setenv("G_MESSAGES_DEBUG", "all", true);
+ } else {
+ g_log_set_handler(NULL, G_LOG_LEVEL_WARNING | G_LOG_LEVEL_CRITICAL |
+ G_LOG_LEVEL_ERROR, g_log_default_handler, NULL);
+ }
+
+ /*
+ * Now create a vhost-user socket that we will receive messages
+ * on. Once we have our handler set up we can enter the glib main
+ * loop.
+ */
+ if (socket_path) {
+ g_autoptr(GSocketAddress) addr = g_unix_socket_address_new(socket_path);
+ g_autoptr(GSocket) bind_socket = g_socket_new(G_SOCKET_FAMILY_UNIX,
+ G_SOCKET_TYPE_STREAM, G_SOCKET_PROTOCOL_DEFAULT, &error);
+
+ if (!g_socket_bind(bind_socket, addr, false, &error)) {
+ g_printerr("Failed to bind to socket at %s (%s).\n",
+ socket_path, error->message);
+ exit(EXIT_FAILURE);
+ }
+ if (!g_socket_listen(bind_socket, &error)) {
+ g_printerr("Failed to listen on socket %s (%s).\n",
+ socket_path, error->message);
+ }
+ g_message("awaiting connection to %s", socket_path);
+ socket = g_socket_accept(bind_socket, NULL, &error);
+ if (!socket) {
+ g_printerr("Failed to accept on socket %s (%s).\n",
+ socket_path, error->message);
+ }
+ } else {
+ socket = g_socket_new_from_fd(socket_fd, &error);
+ if (!socket) {
+ g_printerr("Failed to connect to FD %d (%s).\n",
+ socket_fd, error->message);
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ if (vi2c_parse(&i2c)) {
+ exit(EXIT_FAILURE);
+ }
+
+ /*
+ * Create the main loop first so all the various sources can be
+ * added. As well as catching signals we need to ensure vug_init
+ * can add it's GSource watches.
+ */
+
+ i2c.loop = g_main_loop_new(NULL, FALSE);
+ /* catch exit signals */
+ g_unix_signal_add(SIGHUP, hangup, i2c.loop);
+ g_unix_signal_add(SIGINT, hangup, i2c.loop);
+
+ if (!vug_init(&i2c.dev, VHOST_USER_I2C_MAX_QUEUES, g_socket_get_fd(socket),
+ vi2c_panic, &vuiface)) {
+ g_printerr("Failed to initialize libvhost-user-glib.\n");
+ exit(EXIT_FAILURE);
+ }
+
+
+ g_message("entering main loop, awaiting messages");
+ g_main_loop_run(i2c.loop);
+ g_message("finished main loop, cleaning up");
+
+ g_main_loop_unref(i2c.loop);
+ vi2c_destroy(&i2c);
+}
diff --git a/tools/vhost-user-i2c/meson.build b/tools/vhost-user-i2c/meson.build
new file mode 100644
index 000000000000..4b0156053f5d
--- /dev/null
+++ b/tools/vhost-user-i2c/meson.build
@@ -0,0 +1,10 @@
+executable('vhost-user-i2c', files(
+ 'main.c'),
+ dependencies: [qemuutil, glib, gio],
+ install: true,
+ install_dir: get_option('libexecdir'))
+
+configure_file(input: '50-qemu-i2c.json.in',
+ output: '50-qemu-i2c.json',
+ configuration: { 'libexecdir' : get_option('prefix') / get_option('libexecdir') },
+ install_dir: qemu_datadir / 'vhost-user')
--
2.25.0.rc1.19.g042ed3e048af
next prev parent reply other threads:[~2021-04-05 9:39 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-01 12:12 [PATCH V2 0/6] virtio: Implement generic vhost-user-i2c backend Viresh Kumar
2021-04-01 12:12 ` [PATCH V2 1/6] !Merge: Update virtio headers from kernel Viresh Kumar
2021-04-01 12:12 ` [PATCH V2 2/6] hw/virtio: add boilerplate for vhost-user-i2c device Viresh Kumar
2021-04-01 13:43 ` Alex Bennée
2021-04-01 12:12 ` [PATCH V2 3/6] hw/virtio: add vhost-user-i2c-pci boilerplate Viresh Kumar
2021-04-01 12:12 ` [PATCH V2 4/6] tools/vhost-user-i2c: Add backend driver Viresh Kumar
2021-04-01 13:43 ` Alex Bennée
2021-04-05 9:39 ` Viresh Kumar
2021-04-02 2:55 ` Jie Deng
2021-04-05 5:28 ` Viresh Kumar
2021-04-05 9:38 ` Viresh Kumar [this message]
2021-04-01 12:12 ` [PATCH V2 5/6] docs: add a man page for vhost-user-i2c Viresh Kumar
2021-04-01 12:12 ` [PATCH V2 6/6] MAINTAINERS: Add entry for virtio-i2c Viresh Kumar
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