[PATCH v5 04/14] bus/vmbus: scan and get the network device on FreeBSD

[Srikanth Kaka <srikanth.k@oneconvergence.com>]

Using sysctl, all the devices on the VMBUS are identified by the PMD.
On finding the Network device's device id, it is added to VMBUS dev
list.

Signed-off-by: Srikanth Kaka <srikanth.k@oneconvergence.com>
Signed-off-by: Vag Singh <vag.singh@oneconvergence.com>
Signed-off-by: Anand Thulasiram <avelu@juniper.net>
---
 drivers/bus/vmbus/freebsd/vmbus_bus.c | 268 ++++++++++++++++++++++++++++++++++
 1 file changed, 268 insertions(+)
 create mode 100644 drivers/bus/vmbus/freebsd/vmbus_bus.c

diff --git a/drivers/bus/vmbus/freebsd/vmbus_bus.c b/drivers/bus/vmbus/freebsd/vmbus_bus.c
new file mode 100644
index 0000000..c1a3a5f
--- /dev/null
+++ b/drivers/bus/vmbus/freebsd/vmbus_bus.c
@@ -0,0 +1,268 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright (c) 2018, Microsoft Corporation.
+ * All Rights Reserved.
+ */
+
+#include <rte_eal.h>
+#include <rte_bus_vmbus.h>
+
+#include "private.h"
+#include "vmbus_unix.h"
+
+#include <sys/bus.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+/* Parse UUID. Caller must pass NULL terminated string */
+static int
+parse_sysfs_uuid(const char *filename, rte_uuid_t uu)
+{
+	char in[BUFSIZ];
+
+	memcpy(in, filename, BUFSIZ);
+	if (rte_uuid_parse(in, uu) < 0) {
+		VMBUS_LOG(ERR, "%s not a valid UUID", in);
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Scan one vmbus entry, and fill the devices list from it. */
+static int
+vmbus_scan_one(const char *name, unsigned int unit_num)
+{
+	struct rte_vmbus_device *dev, *dev2;
+	char sysctl_buf[PATH_MAX], sysctl_var[PATH_MAX];
+	size_t guid_len = 36, len = PATH_MAX;
+	char classid[guid_len + 1], deviceid[guid_len + 1];
+
+	dev = calloc(1, sizeof(*dev));
+	if (dev == NULL)
+		return -1;
+
+	/* get class id and device id */
+	snprintf(sysctl_var, len, "dev.%s.%u.%%pnpinfo", name, unit_num);
+	if (sysctlbyname(sysctl_var, &sysctl_buf, &len, NULL, 0) < 0)
+		goto error;
+
+	/* pnpinfo: classid=f912ad6d-2b17-48ea-bd65-f927a61c7684
+	 * deviceid=d34b2567-b9b6-42b9-8778-0a4ec0b955bf
+	 */
+	if (sysctl_buf[0] == 'c' && sysctl_buf[1] == 'l' &&
+	    sysctl_buf[7] == '=') {
+		memcpy(classid, &sysctl_buf[8], guid_len);
+		classid[guid_len] = '\0';
+	}
+	if (parse_sysfs_uuid(classid, dev->class_id) < 0)
+		goto error;
+
+	/* skip non-network devices */
+	if (rte_uuid_compare(dev->class_id, vmbus_nic_uuid) != 0) {
+		free(dev);
+		return 0;
+	}
+
+	if (sysctl_buf[45] == 'd' && sysctl_buf[46] == 'e' &&
+	    sysctl_buf[47] == 'v' && sysctl_buf[53] == '=') {
+		memcpy(deviceid, &sysctl_buf[54], guid_len);
+		deviceid[guid_len] = '\0';
+	}
+	if (parse_sysfs_uuid(deviceid, dev->device_id) < 0)
+		goto error;
+
+	if (!strcmp(name, "hv_uio"))
+		dev->uio_num = unit_num;
+	else
+		dev->uio_num = -1;
+	dev->device.bus = &rte_vmbus_bus.bus;
+	dev->device.numa_node = 0;
+	dev->device.name = strdup(deviceid);
+	if (!dev->device.name)
+		goto error;
+
+	dev->device.devargs = vmbus_devargs_lookup(dev);
+
+	dev->intr_handle = rte_intr_instance_alloc(RTE_INTR_INSTANCE_F_PRIVATE);
+	if (dev->intr_handle == NULL)
+		goto error;
+
+	/* device is valid, add in list (sorted) */
+	VMBUS_LOG(DEBUG, "Adding vmbus device %s", name);
+
+	TAILQ_FOREACH(dev2, &rte_vmbus_bus.device_list, next) {
+		int ret;
+
+		ret = rte_uuid_compare(dev->device_id, dev2->device_id);
+		if (ret > 0)
+			continue;
+
+		if (ret < 0) {
+			vmbus_insert_device(dev2, dev);
+		} else { /* already registered */
+			VMBUS_LOG(NOTICE,
+				"%s already registered", name);
+			free(dev);
+		}
+		return 0;
+	}
+
+	vmbus_add_device(dev);
+	return 0;
+error:
+	VMBUS_LOG(DEBUG, "failed");
+
+	free(dev);
+	return -1;
+}
+
+static int
+vmbus_unpack(char *walker, char *ep, char **str)
+{
+	int ret = 0;
+
+	*str = strdup(walker);
+	if (*str == NULL) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	if (walker + strnlen(walker, ep - walker) >= ep) {
+		ret = -EINVAL;
+		goto exit;
+	}
+exit:
+	return ret;
+}
+
+/*
+ * Scan the content of the vmbus, and the devices in the devices list
+ */
+int
+rte_vmbus_scan(void)
+{
+	struct u_device udev;
+	struct u_businfo ubus;
+	int dev_idx, dev_ptr, name2oid[2], oid[CTL_MAXNAME + 12], error;
+	size_t oidlen, rlen, ub_size;
+	uintptr_t vmbus_handle = 0;
+	char *walker, *ep;
+	char name[16] = "hw.bus.devices";
+	char *dd_name, *dd_desc, *dd_drivername, *dd_pnpinfo, *dd_location;
+
+	/*
+	 * devinfo FreeBSD APP logic to fetch all the VMBus devices
+	 * using SYSCTLs
+	 */
+	name2oid[0] = 0;
+	name2oid[1] = 3;
+	oidlen = sizeof(oid);
+	error = sysctl(name2oid, 2, oid, &oidlen, name, strlen(name));
+	if (error < 0) {
+		VMBUS_LOG(DEBUG, "can't find hw.bus.devices sysctl node");
+		return -ENOENT;
+	}
+	oidlen /= sizeof(int);
+	if (oidlen > CTL_MAXNAME) {
+		VMBUS_LOG(DEBUG, "hw.bus.devices oid is too large");
+		return -EINVAL;
+	}
+
+	ub_size = sizeof(ubus);
+	if (sysctlbyname("hw.bus.info", &ubus, &ub_size, NULL, 0) != 0) {
+		VMBUS_LOG(DEBUG, "sysctlbyname(\"hw.bus.info\", ...) failed");
+		return -EINVAL;
+	}
+	if ((ub_size != sizeof(ubus)) ||
+	    (ubus.ub_version != BUS_USER_VERSION)) {
+		VMBUS_LOG(DEBUG,
+			"kernel bus interface version mismatch: kernel %d expected %d",
+			ubus.ub_version, BUS_USER_VERSION);
+		return -EINVAL;
+	}
+
+	oid[oidlen++] = ubus.ub_generation;
+	dev_ptr = oidlen++;
+
+	/*
+	 * Scan devices.
+	 *
+	 * Stop after a fairly insane number to avoid death in the case
+	 * of kernel corruption.
+	 */
+
+	for (dev_idx = 0; dev_idx < 10000; dev_idx++) {
+		/*
+		 * Get the device information.
+		 */
+		oid[dev_ptr] = dev_idx;
+		rlen = sizeof(udev);
+		error = sysctl(oid, oidlen, &udev, &rlen, NULL, 0);
+		if (error < 0) {
+			if (errno == ENOENT)    /* end of list */
+				break;
+			if (errno != EINVAL)    /* gen count skip, restart */
+				VMBUS_LOG(DEBUG, "sysctl hw.bus.devices.%d",
+					dev_idx);
+			return errno;
+		}
+		if (rlen != sizeof(udev)) {
+			VMBUS_LOG(DEBUG,
+				"sysctl returned wrong data %zd bytes instead of %zd",
+				rlen, sizeof(udev));
+			return -EINVAL;
+		}
+
+		walker = udev.dv_fields;
+		ep = walker + sizeof(udev.dv_fields);
+		dd_name = NULL;
+		dd_desc = NULL;
+		dd_drivername = NULL;
+		dd_pnpinfo = NULL;
+		dd_location = NULL;
+
+		error = vmbus_unpack(walker, ep, &dd_name);
+		if (error < 0)
+			return error;
+		walker += strlen(walker) + 1;
+
+		error = vmbus_unpack(walker, ep, &dd_desc);
+		if (error < 0)
+			return error;
+		walker += strlen(walker) + 1;
+
+		error = vmbus_unpack(walker, ep, &dd_drivername);
+		if (error < 0)
+			return error;
+		walker += strlen(walker) + 1;
+
+		error = vmbus_unpack(walker, ep, &dd_pnpinfo);
+		if (error < 0)
+			return error;
+		walker += strlen(walker) + 1;
+
+		error = vmbus_unpack(walker, ep, &dd_location);
+		if (error < 0)
+			return error;
+
+		if (*dd_drivername && !(strcmp(dd_drivername, "vmbus")))
+			vmbus_handle = udev.dv_handle;
+
+		if (vmbus_handle && (vmbus_handle == udev.dv_parent)
+		    && *dd_pnpinfo && *dd_name) {
+			unsigned int driver_len = 0, unit_num = 0;
+			char *endptr;
+
+			driver_len = strlen(dd_drivername);
+			unit_num = strtoull(&dd_name[driver_len], &endptr, 10);
+			VMBUS_LOG(DEBUG, "Device name:%s, pnpinfo:%s",
+				dd_name, dd_pnpinfo);
+
+			if (vmbus_scan_one(dd_drivername, unit_num) < 0)
+				goto error;
+		}
+	}
+	return 0;
+error:
+	return -1;
+}
-- 
1.8.3.1