[dpdk-dev] [PATCH 04/11] bus/vmbus: get device resource values using sysctl

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

The UIO device's relid, monitor id, etc values are retrieved using
following sysctl variables:
$ sysctl dev.hv_uio.0
dev.hv_uio.0.send_buf.gpadl: 925241
dev.hv_uio.0.send_buf.size: 16777216
dev.hv_uio.0.recv_buf.gpadl: 925240
dev.hv_uio.0.recv_buf.size: 32505856
dev.hv_uio.0.monitor_page.size: 4096
dev.hv_uio.0.int_page.size: 4096

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_uio.c | 98 ++++++++++++++++++++++-----
 1 file changed, 81 insertions(+), 17 deletions(-)

diff --git a/drivers/bus/vmbus/freebsd/vmbus_uio.c b/drivers/bus/vmbus/freebsd/vmbus_uio.c
index b52ca5bf1d..fdd37dac3a 100644
--- a/drivers/bus/vmbus/freebsd/vmbus_uio.c
+++ b/drivers/bus/vmbus/freebsd/vmbus_uio.c
@@ -10,6 +10,8 @@
 #include <inttypes.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
 
 #include <rte_log.h>
 #include <rte_bus.h>
@@ -24,8 +26,18 @@
 /** Pathname of VMBUS devices directory. */
 #define SYSFS_VMBUS_DEVICES "/sys/bus/vmbus/devices"
 
+const char *driver_name = "hv_uio";
 static void *vmbus_map_addr;
 
+/* Check map names with kernel names */
+static const char *map_names[VMBUS_MAX_RESOURCE] = {
+	[HV_TXRX_RING_MAP] = "txrx_rings",
+	[HV_INT_PAGE_MAP]  = "int_page",
+	[HV_MON_PAGE_MAP]  = "monitor_page",
+	[HV_RECV_BUF_MAP]  = "recv_buf",
+	[HV_SEND_BUF_MAP]  = "send_buf",
+};
+
 /* Control interrupts */
 void vmbus_uio_irq_control(struct rte_vmbus_device *dev, int32_t onoff)
 {
@@ -72,14 +84,75 @@ vmbus_uio_free_resource(struct rte_vmbus_device *dev,
 	}
 }
 
+static int
+sysctl_get_vmbus_device_info(struct rte_vmbus_device *dev)
+{
+	char sysctlBuffer[PATH_MAX];
+	char sysctlVar[PATH_MAX];
+	size_t len = PATH_MAX, sysctl_len;
+	unsigned long tmp;
+	int i;
+
+	snprintf(sysctlBuffer, len, "dev.%s.%d", driver_name, dev->uio_num);
+
+	sysctl_len = sizeof(unsigned long);
+	/* get relid */
+	snprintf(sysctlVar, len, "%s.channel.ch_id", sysctlBuffer);
+	if (sysctlbyname(sysctlVar, &tmp, &sysctl_len, NULL, 0) < 0) {
+		VMBUS_LOG(ERR, "could not read %s", sysctlVar);
+		goto error;
+	}
+	dev->relid = tmp;
+
+	/* get monitor id */
+	snprintf(sysctlVar, len, "%s.channel.%u.monitor_id", sysctlBuffer,
+		 dev->relid);
+	if (sysctlbyname(sysctlVar, &tmp, &sysctl_len, NULL, 0) < 0) {
+		VMBUS_LOG(ERR, "could not read %s", sysctlVar);
+		goto error;
+	}
+	dev->monitor_id = tmp;
+
+	/* Extract resource value */
+	for (i = 0; i < VMBUS_MAX_RESOURCE; i++) {
+		struct rte_mem_resource *res = &dev->resource[i];
+		unsigned long size, gpad = 0;
+		size_t sizelen = sizeof(len);
+
+		snprintf(sysctlVar, sizeof(sysctlVar), "%s.%s.size",
+			 sysctlBuffer, map_names[i]);
+		if (sysctlbyname(sysctlVar, &size, &sizelen, NULL, 0) < 0) {
+			VMBUS_LOG(ERR,
+				"could not read %s", sysctlVar);
+			goto error;
+		}
+		res->len = size;
+
+		if (i == HV_RECV_BUF_MAP || i == HV_SEND_BUF_MAP) {
+			snprintf(sysctlVar, sizeof(sysctlVar), "%s.%s.gpadl",
+				 sysctlBuffer, map_names[i]);
+			if (sysctlbyname(sysctlVar, &gpad, &sizelen, NULL, 0) < 0) {
+				VMBUS_LOG(ERR,
+					"could not read %s", sysctlVar);
+				goto error;
+			}
+			/* put the GPAD value in physical address */
+			res->phys_addr = gpad;
+		}
+	}
+	return 0;
+error:
+	return -1;
+}
+
 int
 vmbus_uio_alloc_resource(struct rte_vmbus_device *dev,
 			 struct mapped_vmbus_resource **uio_res)
 {
-	char devname[PATH_MAX]; /* contains the /dev/uioX */
+	char devname[PATH_MAX]; /* contains the /dev/hv_uioX */
 
 	/* save fd if in primary process */
-	snprintf(devname, sizeof(devname), "/dev/uio%u", dev->uio_num);
+	snprintf(devname, sizeof(devname), "/dev/hv_uio%u", dev->uio_num);
 	dev->intr_handle.fd = open(devname, O_RDWR);
 	if (dev->intr_handle.fd < 0) {
 		VMBUS_LOG(ERR, "Cannot open %s: %s",
@@ -98,8 +171,10 @@ vmbus_uio_alloc_resource(struct rte_vmbus_device *dev,
 	strlcpy((*uio_res)->path, devname, PATH_MAX);
 	rte_uuid_copy((*uio_res)->id, dev->device_id);
 
-	return 0;
+	if (sysctl_get_vmbus_device_info(dev) < 0)
+		goto error;
 
+	return 0;
 error:
 	vmbus_uio_free_resource(dev, *uio_res);
 	return -1;
@@ -338,23 +413,12 @@ static int vmbus_uio_sysfs_read(const char *dir, const char *name,
 	return ret;
 }
 
-static bool vmbus_uio_ring_present(const struct rte_vmbus_device *dev,
-				   uint32_t relid)
-{
-	char ring_path[PATH_MAX];
-
-	/* Check if kernel has subchannel sysfs files */
-	snprintf(ring_path, sizeof(ring_path),
-		 "%s/%s/channels/%u/ring",
-		 SYSFS_VMBUS_DEVICES, dev->device.name, relid);
-
-	return access(ring_path, R_OK|W_OK) == 0;
-}
-
 bool vmbus_uio_subchannels_supported(const struct rte_vmbus_device *dev,
 				     const struct vmbus_channel *chan)
 {
-	return vmbus_uio_ring_present(dev, chan->relid);
+	RTE_SET_USED(dev);
+	RTE_SET_USED(chan);
+	return true;
 }
 
 static bool vmbus_isnew_subchannel(struct vmbus_channel *primary,
-- 
2.30.2