[dpdk-dev] [PATCH 9/9] eal: relocate hotplug code from ethdev

[David Marchand <david.marchand@6wind.com>]

hotplug which deals with resources should come from the layer that already
handles them, i.e. eal.

Signed-off-by: David Marchand <david.marchand@6wind.com>
---
 lib/librte_eal/bsdapp/eal/rte_eal_version.map   |   8 +
 lib/librte_eal/common/eal_common_dev.c          |  39 ++++
 lib/librte_eal/common/eal_common_pci.c          |  11 +-
 lib/librte_eal/common/include/rte_dev.h         |  25 +++
 lib/librte_eal/linuxapp/eal/rte_eal_version.map |   8 +
 lib/librte_ether/rte_ethdev.c                   | 258 ++++--------------------
 6 files changed, 125 insertions(+), 224 deletions(-)

diff --git a/lib/librte_eal/bsdapp/eal/rte_eal_version.map b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
index 9d7adf1..9aad048 100644
--- a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
@@ -135,3 +135,11 @@ DPDK_2.2 {
 	rte_xen_dom0_supported;
 
 } DPDK_2.1;
+
+DPDK_2.3 {
+	global:
+
+	rte_eal_dev_attach;
+	rte_eal_dev_detach;
+
+} DPDK_2.2;
diff --git a/lib/librte_eal/common/eal_common_dev.c b/lib/librte_eal/common/eal_common_dev.c
index 5137172..ec04b3a 100644
--- a/lib/librte_eal/common/eal_common_dev.c
+++ b/lib/librte_eal/common/eal_common_dev.c
@@ -155,3 +155,42 @@ rte_eal_vdev_uninit(const char *name)
 	RTE_LOG(ERR, EAL, "no driver found for %s\n", name);
 	return -EINVAL;
 }
+
+int rte_eal_dev_attach(const char *name, const char *devargs)
+{
+	struct rte_pci_addr addr;
+	int ret = -1;
+
+	if (eal_parse_pci_DomBDF(name, &addr) == 0) {
+		if (rte_eal_pci_probe_one(&addr) < 0)
+			goto err;
+
+	} else {
+		if (rte_eal_vdev_init(name, devargs))
+			goto err;
+	}
+
+	return 0;
+
+err:
+	RTE_LOG(ERR, EAL, "Driver, cannot attach the device\n");
+	return ret;
+}
+
+int rte_eal_dev_detach(const char *name)
+{
+	struct rte_pci_addr addr;
+
+	if (eal_parse_pci_DomBDF(name, &addr) == 0) {
+		if (rte_eal_pci_detach(&addr) < 0)
+			goto err;
+	} else {
+		if (rte_eal_vdev_uninit(name))
+			goto err;
+	}
+	return 0;
+
+err:
+	RTE_LOG(ERR, EAL, "Driver, cannot detach the device\n");
+	return -1;
+}
diff --git a/lib/librte_eal/common/eal_common_pci.c b/lib/librte_eal/common/eal_common_pci.c
index 1e12776..d9aa66b 100644
--- a/lib/librte_eal/common/eal_common_pci.c
+++ b/lib/librte_eal/common/eal_common_pci.c
@@ -332,6 +332,11 @@ rte_eal_pci_probe_one(const struct rte_pci_addr *addr)
 	if (addr == NULL)
 		return -1;
 
+	/* update current pci device in global list, kernel bindings might have
+	 * changed since last time we looked at it */
+	if (pci_refresh_device(addr) < 0)
+		goto err_return;
+
 	TAILQ_FOREACH(dev, &pci_device_list, next) {
 		if (rte_eal_compare_pci_addr(&dev->addr, addr))
 			continue;
@@ -344,9 +349,9 @@ rte_eal_pci_probe_one(const struct rte_pci_addr *addr)
 	return -1;
 
 err_return:
-	RTE_LOG(WARNING, EAL, "Requested device " PCI_PRI_FMT
-			" cannot be used\n", dev->addr.domain, dev->addr.bus,
-			dev->addr.devid, dev->addr.function);
+	RTE_LOG(WARNING, EAL,
+		"Requested device " PCI_PRI_FMT " cannot be used\n",
+		addr->domain, addr->bus, addr->devid, addr->function);
 	return -1;
 }
 
diff --git a/lib/librte_eal/common/include/rte_dev.h b/lib/librte_eal/common/include/rte_dev.h
index df69e28..6f026ff 100644
--- a/lib/librte_eal/common/include/rte_dev.h
+++ b/lib/librte_eal/common/include/rte_dev.h
@@ -182,6 +182,31 @@ int rte_eal_vdev_init(const char *name, const char *args);
  */
 int rte_eal_vdev_uninit(const char *name);
 
+/**
+ * Attach a resource to a registered driver.
+ *
+ * @param name
+ *   The resource name, that refers to a pci resource or some private
+ *   way of designating a resource for vdev drivers. Based on this
+ *   resource name, eal will identify a driver capable of handling
+ *   this resource and pass this resource to the driver probing
+ *   function.
+ * @param devargs
+ *   Device arguments to be passed to the driver.
+ * @return
+ *   0 on success, negative on error.
+ */
+int rte_eal_dev_attach(const char *name, const char *devargs);
+
+/**
+ * Detach a resource from its driver.
+ *
+ * @param name
+ *   Same description as for rte_eal_dev_attach().
+ *   Here, eal will call the driver detaching function.
+ */
+int rte_eal_dev_detach(const char *name);
+
 #define PMD_REGISTER_DRIVER(d)\
 void devinitfn_ ##d(void);\
 void __attribute__((constructor, used)) devinitfn_ ##d(void)\
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index cbe175f..ba0ff56 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -138,3 +138,11 @@ DPDK_2.2 {
 	rte_xen_dom0_supported;
 
 } DPDK_2.1;
+
+DPDK_2.3 {
+	global:
+
+	rte_eal_dev_attach;
+	rte_eal_dev_detach;
+
+} DPDK_2.2;
diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 5ba7479..5a5d419 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -72,6 +72,7 @@
 static const char *MZ_RTE_ETH_DEV_DATA = "rte_eth_dev_data";
 struct rte_eth_dev rte_eth_devices[RTE_MAX_ETHPORTS];
 static struct rte_eth_dev_data *rte_eth_dev_data;
+static uint8_t eth_dev_last_created_port;
 static uint8_t nb_ports;
 
 /* spinlock for eth device callbacks */
@@ -210,6 +211,7 @@ rte_eth_dev_allocate(const char *name, enum rte_eth_dev_type type)
 	eth_dev->data->port_id = port_id;
 	eth_dev->attached = DEV_ATTACHED;
 	eth_dev->dev_type = type;
+	eth_dev_last_created_port = port_id;
 	nb_ports++;
 	return eth_dev;
 }
@@ -364,100 +366,6 @@ rte_eth_dev_count(void)
 	return nb_ports;
 }
 
-static enum rte_eth_dev_type
-rte_eth_dev_get_device_type(uint8_t port_id)
-{
-	if (!rte_eth_dev_is_valid_port(port_id))
-		return RTE_ETH_DEV_UNKNOWN;
-	return rte_eth_devices[port_id].dev_type;
-}
-
-static int
-rte_eth_dev_get_addr_by_port(uint8_t port_id, struct rte_pci_addr *addr)
-{
-	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
-
-	if (addr == NULL) {
-		RTE_PMD_DEBUG_TRACE("Null pointer is specified\n");
-		return -EINVAL;
-	}
-
-	*addr = rte_eth_devices[port_id].pci_dev->addr;
-	return 0;
-}
-
-static int
-rte_eth_dev_get_name_by_port(uint8_t port_id, char *name)
-{
-	char *tmp;
-
-	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
-
-	if (name == NULL) {
-		RTE_PMD_DEBUG_TRACE("Null pointer is specified\n");
-		return -EINVAL;
-	}
-
-	/* shouldn't check 'rte_eth_devices[i].data',
-	 * because it might be overwritten by VDEV PMD */
-	tmp = rte_eth_dev_data[port_id].name;
-	strcpy(name, tmp);
-	return 0;
-}
-
-static int
-rte_eth_dev_get_port_by_name(const char *name, uint8_t *port_id)
-{
-	int i;
-
-	if (name == NULL) {
-		RTE_PMD_DEBUG_TRACE("Null pointer is specified\n");
-		return -EINVAL;
-	}
-
-	*port_id = RTE_MAX_ETHPORTS;
-
-	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
-
-		if (!strncmp(name,
-			rte_eth_dev_data[i].name, strlen(name))) {
-
-			*port_id = i;
-
-			return 0;
-		}
-	}
-	return -ENODEV;
-}
-
-static int
-rte_eth_dev_get_port_by_addr(const struct rte_pci_addr *addr, uint8_t *port_id)
-{
-	int i;
-	struct rte_pci_device *pci_dev = NULL;
-
-	if (addr == NULL) {
-		RTE_PMD_DEBUG_TRACE("Null pointer is specified\n");
-		return -EINVAL;
-	}
-
-	*port_id = RTE_MAX_ETHPORTS;
-
-	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
-
-		pci_dev = rte_eth_devices[i].pci_dev;
-
-		if (pci_dev &&
-			!rte_eal_compare_pci_addr(&pci_dev->addr, addr)) {
-
-			*port_id = i;
-
-			return 0;
-		}
-	}
-	return -ENODEV;
-}
-
 static int
 rte_eth_dev_is_detachable(uint8_t port_id)
 {
@@ -482,127 +390,50 @@ rte_eth_dev_is_detachable(uint8_t port_id)
 	return !(dev_flags & RTE_ETH_DEV_DETACHABLE);
 }
 
-/* attach the new physical device, then store port_id of the device */
-static int
-rte_eth_dev_attach_pdev(struct rte_pci_addr *addr, uint8_t *port_id)
-{
-	/* re-construct pci_device_list */
-	if (rte_eal_pci_scan())
-		goto err;
-	/* Invoke probe func of the driver can handle the new device. */
-	if (rte_eal_pci_probe_one(addr))
-		goto err;
-
-	if (rte_eth_dev_get_port_by_addr(addr, port_id))
-		goto err;
-
-	return 0;
-err:
-	return -1;
-}
-
-/* detach the new physical device, then store pci_addr of the device */
-static int
-rte_eth_dev_detach_pdev(uint8_t port_id, struct rte_pci_addr *addr)
-{
-	struct rte_pci_addr freed_addr;
-	struct rte_pci_addr vp;
-
-	/* get pci address by port id */
-	if (rte_eth_dev_get_addr_by_port(port_id, &freed_addr))
-		goto err;
-
-	/* Zeroed pci addr means the port comes from virtual device */
-	vp.domain = vp.bus = vp.devid = vp.function = 0;
-	if (rte_eal_compare_pci_addr(&vp, &freed_addr) == 0)
-		goto err;
-
-	/* invoke devuninit func of the pci driver,
-	 * also remove the device from pci_device_list */
-	if (rte_eal_pci_detach(&freed_addr))
-		goto err;
-
-	*addr = freed_addr;
-	return 0;
-err:
-	return -1;
-}
-
-/* attach the new virtual device, then store port_id of the device */
-static int
-rte_eth_dev_attach_vdev(const char *vdevargs, uint8_t *port_id)
-{
-	char *name = NULL, *args = NULL;
-	int ret = -1;
-
-	/* parse vdevargs, then retrieve device name and args */
-	if (rte_eal_parse_devargs_str(vdevargs, &name, &args))
-		goto end;
-
-	/* walk around dev_driver_list to find the driver of the device,
-	 * then invoke probe function of the driver.
-	 * rte_eal_vdev_init() updates port_id allocated after
-	 * initialization.
-	 */
-	if (rte_eal_vdev_init(name, args))
-		goto end;
-
-	if (rte_eth_dev_get_port_by_name(name, port_id))
-		goto end;
-
-	ret = 0;
-end:
-	free(name);
-	free(args);
-
-	return ret;
-}
-
-/* detach the new virtual device, then store the name of the device */
-static int
-rte_eth_dev_detach_vdev(uint8_t port_id, char *vdevname)
-{
-	char name[RTE_ETH_NAME_MAX_LEN];
-
-	/* get device name by port id */
-	if (rte_eth_dev_get_name_by_port(port_id, name))
-		goto err;
-	/* walk around dev_driver_list to find the driver of the device,
-	 * then invoke uninit function of the driver */
-	if (rte_eal_vdev_uninit(name))
-		goto err;
-
-	strncpy(vdevname, name, sizeof(name));
-	return 0;
-err:
-	return -1;
-}
-
 /* attach the new device, then store port_id of the device */
 int
 rte_eth_dev_attach(const char *devargs, uint8_t *port_id)
 {
-	struct rte_pci_addr addr;
 	int ret = -1;
+	int current = eth_dev_last_created_port;
+	char *name = NULL, *args;
 
 	if ((devargs == NULL) || (port_id == NULL)) {
 		ret = -EINVAL;
 		goto err;
 	}
 
-	if (eal_parse_pci_DomBDF(devargs, &addr) == 0) {
-		ret = rte_eth_dev_attach_pdev(&addr, port_id);
-		if (ret < 0)
-			goto err;
-	} else {
-		ret = rte_eth_dev_attach_vdev(devargs, port_id);
-		if (ret < 0)
-			goto err;
+	name = strdup(devargs);
+	if (!name)
+		goto err;
+
+	args = strchr(name, ',');
+	if (args) {
+		args[0] = '\0';
+		args++;
 	}
 
+	ret = rte_eal_dev_attach(name, args);
+	if (ret < 0)
+		goto err;
+
+	/* no point looking at eth_dev_last_created_port if no port exists */
+	if (!nb_ports) {
+		ret = -1;
+		goto err;
+	}
+	/* if nothing happened, there is a bug here, since some driver told us
+	 * it did attach a device, but did not create a port */
+	if (current == eth_dev_last_created_port) {
+		ret = -1;
+		goto err;
+	}
+	*port_id = eth_dev_last_created_port;
+
+	free(name);
 	return 0;
 err:
-	RTE_LOG(ERR, EAL, "Driver, cannot attach the device\n");
+	free(name);
 	return ret;
 }
 
@@ -610,7 +441,6 @@ err:
 int
 rte_eth_dev_detach(uint8_t port_id, char *name)
 {
-	struct rte_pci_addr addr;
 	int ret = -1;
 
 	if (name == NULL) {
@@ -618,33 +448,19 @@ rte_eth_dev_detach(uint8_t port_id, char *name)
 		goto err;
 	}
 
-	/* check whether the driver supports detach feature, or not */
+	/* FIXME: move this to eal, once device flags are relocated there */
 	if (rte_eth_dev_is_detachable(port_id))
 		goto err;
 
-	if (rte_eth_dev_get_device_type(port_id) == RTE_ETH_DEV_PCI) {
-		ret = rte_eth_dev_get_addr_by_port(port_id, &addr);
-		if (ret < 0)
-			goto err;
-
-		ret = rte_eth_dev_detach_pdev(port_id, &addr);
-		if (ret < 0)
-			goto err;
-
-		snprintf(name, RTE_ETH_NAME_MAX_LEN,
-			"%04x:%02x:%02x.%d",
-			addr.domain, addr.bus,
-			addr.devid, addr.function);
-	} else {
-		ret = rte_eth_dev_detach_vdev(port_id, name);
-		if (ret < 0)
-			goto err;
-	}
+	snprintf(name, sizeof(rte_eth_devices[port_id].data->name),
+		 "%s", rte_eth_devices[port_id].data->name);
+	ret = rte_eal_dev_detach(name);
+	if (ret < 0)
+		goto err;
 
 	return 0;
 
 err:
-	RTE_LOG(ERR, EAL, "Driver, cannot detach the device\n");
 	return ret;
 }
 
-- 
1.9.1