[dpdk-dev] [PATCH v2 02/11] bus/vmbus: scan and get the network device

[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.

v2 - replaced strncpy with memcpy
   - replaced malloc.h with stdlib.h

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 | 241 +++++++++++++++-----------
 drivers/net/netvsc/hn_rxtx.c          |   2 +-
 2 files changed, 145 insertions(+), 98 deletions(-)

diff --git a/drivers/bus/vmbus/freebsd/vmbus_bus.c b/drivers/bus/vmbus/freebsd/vmbus_bus.c
index 3c924eee14..47b85c18c0 100644
--- a/drivers/bus/vmbus/freebsd/vmbus_bus.c
+++ b/drivers/bus/vmbus/freebsd/vmbus_bus.c
@@ -22,8 +22,9 @@
 #include "eal_filesystem.h"
 #include "private.h"
 
-/** Pathname of VMBUS devices directory. */
-#define SYSFS_VMBUS_DEVICES "/sys/bus/vmbus/devices"
+#include <sys/bus.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
 
 /*
  * GUID associated with network devices
@@ -39,44 +40,15 @@ static const rte_uuid_t vmbus_nic_uuid = {
 
 extern struct rte_vmbus_bus rte_vmbus_bus;
 
-/* Read sysfs file to get UUID */
+/* Parse UUID. Caller must pass NULL terminated string */
 static int
 parse_sysfs_uuid(const char *filename, rte_uuid_t uu)
 {
-	char buf[BUFSIZ];
-	char *cp, *in = buf;
-	FILE *f;
-
-	f = fopen(filename, "r");
-	if (f == NULL) {
-		VMBUS_LOG(ERR, "cannot open sysfs value %s: %s",
-			  filename, strerror(errno));
-		return -1;
-	}
-
-	if (fgets(buf, sizeof(buf), f) == NULL) {
-		VMBUS_LOG(ERR, "cannot read sysfs value %s",
-				filename);
-		fclose(f);
-		return -1;
-	}
-	fclose(f);
-
-	cp = strchr(buf, '\n');
-	if (cp)
-		*cp = '\0';
-
-	/* strip { } notation */
-	if (buf[0] == '{') {
-		in = buf + 1;
-		cp = strchr(in, '}');
-		if (cp)
-			*cp = '\0';
-	}
+	char in[BUFSIZ];
 
+	memcpy(in, filename, BUFSIZ);
 	if (rte_uuid_parse(in, uu) < 0) {
-		VMBUS_LOG(ERR, "%s %s not a valid UUID",
-			filename, buf);
+		VMBUS_LOG(ERR, "%s not a valid UUID", in);
 		return -1;
 	}
 
@@ -228,35 +200,33 @@ rte_vmbus_unmap_device(struct rte_vmbus_device *dev)
 	vmbus_uio_unmap_resource(dev);
 }
 
-/* Scan one vmbus sysfs entry, and fill the devices list from it. */
+/* Scan one vmbus entry, and fill the devices list from it. */
 static int
-vmbus_scan_one(const char *name)
+vmbus_scan_one(const char *name, unsigned int unit_num)
 {
 	struct rte_vmbus_device *dev, *dev2;
-	char filename[PATH_MAX];
-	char dirname[PATH_MAX];
-	unsigned long tmp;
+	char sysctlBuffer[PATH_MAX], sysctlVar[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;
 
-	dev->device.bus = &rte_vmbus_bus.bus;
-	dev->device.name = strdup(name);
-	if (!dev->device.name)
+	/* get class id and device id */
+	snprintf(sysctlVar, len, "dev.%s.%u.%%pnpinfo", name, unit_num);
+	if (sysctlbyname(sysctlVar, &sysctlBuffer, &len, NULL, 0) < 0)
 		goto error;
 
-	/* sysfs base directory
-	 *   /sys/bus/vmbus/devices/7a08391f-f5a0-4ac0-9802-d13fd964f8df
-	 * or on older kernel
-	 *   /sys/bus/vmbus/devices/vmbus_1
+	/* pnpinfo: classid=f912ad6d-2b17-48ea-bd65-f927a61c7684
+	 * deviceid=d34b2567-b9b6-42b9-8778-0a4ec0b955bf
 	 */
-	snprintf(dirname, sizeof(dirname), "%s/%s",
-		 SYSFS_VMBUS_DEVICES, name);
-
-	/* get device class  */
-	snprintf(filename, sizeof(filename), "%s/class_id", dirname);
-	if (parse_sysfs_uuid(filename, dev->class_id) < 0)
+	if (sysctlBuffer[0] == 'c' && sysctlBuffer[1] == 'l' &&
+	    sysctlBuffer[7] == '=') {
+		memcpy(classid, &sysctlBuffer[8], guid_len);
+		classid[guid_len] = '\0';
+	}
+	if (parse_sysfs_uuid(classid, dev->class_id) < 0)
 		goto error;
 
 	/* skip non-network devices */
@@ -265,35 +235,23 @@ vmbus_scan_one(const char *name)
 		return 0;
 	}
 
-	/* get device id */
-	snprintf(filename, sizeof(filename), "%s/device_id", dirname);
-	if (parse_sysfs_uuid(filename, dev->device_id) < 0)
-		goto error;
-
-	/* get relid */
-	snprintf(filename, sizeof(filename), "%s/id", dirname);
-	if (eal_parse_sysfs_value(filename, &tmp) < 0)
+	if (sysctlBuffer[45] == 'd' && sysctlBuffer[46] == 'e' &&
+	    sysctlBuffer[47] == 'v' && sysctlBuffer[53] == '=') {
+		memcpy(deviceid, &sysctlBuffer[54], guid_len);
+		deviceid[guid_len] = '\0';
+	}
+	if (parse_sysfs_uuid(deviceid, dev->device_id) < 0)
 		goto error;
-	dev->relid = tmp;
 
-	/* get monitor id */
-	snprintf(filename, sizeof(filename), "%s/monitor_id", dirname);
-	if (eal_parse_sysfs_value(filename, &tmp) < 0)
+	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->monitor_id = tmp;
-
-	/* get numa node (if present) */
-	snprintf(filename, sizeof(filename), "%s/numa_node",
-		 dirname);
-
-	if (access(filename, R_OK) == 0) {
-		if (eal_parse_sysfs_value(filename, &tmp) < 0)
-			goto error;
-		dev->device.numa_node = tmp;
-	} else {
-		/* if no NUMA support, set default to 0 */
-		dev->device.numa_node = SOCKET_ID_ANY;
-	}
 
 	dev->device.devargs = vmbus_devargs_lookup(dev);
 
@@ -332,31 +290,120 @@ vmbus_scan_one(const char *name)
 int
 rte_vmbus_scan(void)
 {
-	struct dirent *e;
-	DIR *dir;
-
-	dir = opendir(SYSFS_VMBUS_DEVICES);
-	if (dir == NULL) {
-		if (errno == ENOENT)
-			return 0;
+	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;
+	}
 
-		VMBUS_LOG(ERR, "opendir %s failed: %s",
-			  SYSFS_VMBUS_DEVICES, strerror(errno));
-		return -1;
+	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;
 	}
 
-	while ((e = readdir(dir)) != NULL) {
-		if (e->d_name[0] == '.')
-			continue;
+	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;
+		}
 
-		if (vmbus_scan_one(e->d_name) < 0)
-			goto error;
+		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;
+#define UNPACK(x)						 \
+	do {							 \
+		x = strdup(walker);				 \
+		if (x == NULL)					 \
+			return -ENOMEM;				 \
+		if (walker + strnlen(walker, ep - walker) >= ep) \
+			return -EINVAL;				 \
+		walker += strlen(walker) + 1;			 \
+	} while (0)
+
+		UNPACK(dd_name);
+		UNPACK(dd_desc);
+		UNPACK(dd_drivername);
+		UNPACK(dd_pnpinfo);
+		UNPACK(dd_location);
+#undef UNPACK
+		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;
+		}
 	}
-	closedir(dir);
 	return 0;
-
 error:
-	closedir(dir);
 	return -1;
 }
 
diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
index c6bf7cc132..f306f2f3f0 100644
--- a/drivers/net/netvsc/hn_rxtx.c
+++ b/drivers/net/netvsc/hn_rxtx.c
@@ -10,7 +10,7 @@
 #include <errno.h>
 #include <unistd.h>
 #include <strings.h>
-#include <malloc.h>
+#include <stdlib.h>
 
 #include <rte_ethdev.h>
 #include <rte_memcpy.h>
-- 
2.30.1