usbip: vhci extension: modifications to vhci driver

Modification to Kconfig, vhci_hc.c, vhci.h and vhci_sysfs.c.

1. kernel config

Followings are added.

USBIP_VHCI_HC_PORTS: Number of ports per USB/IP virtual host
controller. The default is 8 - same as current VHCI_NPORTS.
USBIP_VHCI_NR_HCS: Number of USB/IP virtual host controllers. The
default is 1. This paratmeter is replaced with USBIP_VHCI_INIT_HCS and
USBIP_VHCI_MAX_HCS included in succeeding dynamic extension patch.

2. the_controller to controllers

the_controller is changed to vhci_pdevs: array of struct
platform_device.

3. vhci_sysfs.c

Sysfs structure is changed as following.

BEFORE:
    /sys/devices/platform
        +-- vhci
            +-- status
            +-- attach
            +-- detach
            +-- usbip_debug

AFTER: example for CONFIG_USBIP_NR_HCS=4
    /sys/devices/platform
        +-- vhci
        |   +-- nports
        |   +-- status
        |   +-- status.1
        |   +-- status.2
        |   +-- status.3
        |   +-- attach
        |   +-- detach
        |   +-- usbip_debug
        +-- vhci.1
        +-- vhci.2
        +-- vhci.3

vhci[.N] is shown for each host controller kobj. vhch.1, vhci.2, ...
are shown only when CONFIG_USBIP_NR_HCS is more than 1. Only 'vhci'
(without number) has user space interfaces. 'nports' is newly added to
give ports-per-controller and number of controlles. Before that, number
of ports is acquired by reading status lines. Status is divided for
each controller to avoid page size (4KB) limitation.

Old userspace tool binaries work with the first status within the first
controller.

Inconsistency between status header and content is fixed.
4th and 5th column are
header:          "dev bus"
content(unused): "000 000"
content(used):   "%08x", devid
Only 1st and 2nd column are used by program. In old version, sscanf()
in parse_status expect no bus column. And bus_id string is shown in the
last column. Then bus in the header is removed and unused content is
replaced with 8 zeros. The sscanf() expects more than 5 columns and new
has 6 columns so there's no compatibility issue in this change.

Signed-off-by: Nobuo Iwata <nobuo.iwata@fujixerox.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 230 insertions, 66 deletions

diff --git a/drivers/usb/usbip/vhci_sysfs.c b/drivers/usb/usbip/vhci_sysfs.c
index 5b5462eb1665..c404017c1b5a 100644
--- a/drivers/usb/usbip/vhci_sysfs.c
+++ b/drivers/usb/usbip/vhci_sysfs.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ * Copyright (C) 2015-2016 Nobuo Iwata
  *
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,6 +21,8 @@
 #include <linux/kthread.h>
 #include <linux/file.h>
 #include <linux/net.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
 
 #include "usbip_common.h"
 #include "vhci.h"
@@ -27,106 +30,190 @@
 /* TODO: refine locking ?*/
 
 /* Sysfs entry to show port status */
-static ssize_t status_show(struct device *dev, struct device_attribute *attr,
-			   char *out)
+static ssize_t status_show_vhci(int pdev_nr, char *out)
 {
+	struct platform_device *pdev = *(vhci_pdevs + pdev_nr);
+	struct vhci_hcd *vhci;
 	char *s = out;
 	int i = 0;
 	unsigned long flags;
 
-	BUG_ON(!the_controller || !out);
+	if (!pdev || !out) {
+		usbip_dbg_vhci_sysfs("show status error\n");
+		return 0;
+	}
+
+	vhci = hcd_to_vhci(platform_get_drvdata(pdev));
 
-	spin_lock_irqsave(&the_controller->lock, flags);
+	spin_lock_irqsave(&vhci->lock, flags);
 
 	/*
 	 * output example:
-	 * prt sta spd dev socket           local_busid
-	 * 000 004 000 000         c5a7bb80 1-2.3
-	 * 001 004 000 000         d8cee980 2-3.4
+	 * port sta spd dev      socket           local_busid
+	 * 0000 004 000 00000000         c5a7bb80 1-2.3
+	 * 0001 004 000 00000000         d8cee980 2-3.4
 	 *
 	 * IP address can be retrieved from a socket pointer address by looking
 	 * up /proc/net/{tcp,tcp6}. Also, a userland program may remember a
 	 * port number and its peer IP address.
 	 */
-	out += sprintf(out,
-		       "prt sta spd bus dev socket           local_busid\n");
-
-	for (i = 0; i < VHCI_NPORTS; i++) {
-		struct vhci_device *vdev = port_to_vdev(i);
+	for (i = 0; i < VHCI_HC_PORTS; i++) {
+		struct vhci_device *vdev = &vhci->vdev[i];
 
 		spin_lock(&vdev->ud.lock);
-		out += sprintf(out, "%03u %03u ", i, vdev->ud.status);
+		out += sprintf(out, "%04u %03u ",
+				    (pdev_nr * VHCI_HC_PORTS) + i,
+				    vdev->ud.status);
 
 		if (vdev->ud.status == VDEV_ST_USED) {
 			out += sprintf(out, "%03u %08x ",
-				       vdev->speed, vdev->devid);
-			out += sprintf(out, "%16p ", vdev->ud.tcp_socket);
-			out += sprintf(out, "%s", dev_name(&vdev->udev->dev));
+					    vdev->speed, vdev->devid);
+			out += sprintf(out, "%16p %s",
+					    vdev->ud.tcp_socket,
+					    dev_name(&vdev->udev->dev));
 
 		} else {
-			out += sprintf(out, "000 000 000 0000000000000000 0-0");
+			out += sprintf(out, "000 00000000 ");
+			out += sprintf(out, "0000000000000000 0-0");
 		}
 
 		out += sprintf(out, "\n");
 		spin_unlock(&vdev->ud.lock);
 	}
 
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock_irqrestore(&vhci->lock, flags);
+
+	return out - s;
+}
+
+static ssize_t status_show_not_ready(int pdev_nr, char *out)
+{
+	char *s = out;
+	int i = 0;
+
+	for (i = 0; i < VHCI_HC_PORTS; i++) {
+		out += sprintf(out, "%04u %03u ",
+				    (pdev_nr * VHCI_HC_PORTS) + i,
+				    VDEV_ST_NOTASSIGNED);
+		out += sprintf(out, "000 00000000 0000000000000000 0-0");
+		out += sprintf(out, "\n");
+	}
+	return out - s;
+}
+
+static int status_name_to_id(const char *name)
+{
+	char *c;
+	long val;
+	int ret;
+
+	c = strchr(name, '.');
+	if (c == NULL)
+		return 0;
 
+	ret = kstrtol(c+1, 10, &val);
+	if (ret < 0)
+		return ret;
+
+	return val;
+}
+
+static ssize_t status_show(struct device *dev,
+			   struct device_attribute *attr, char *out)
+{
+	char *s = out;
+	int pdev_nr;
+
+	out += sprintf(out,
+		       "port sta spd dev      socket           local_busid\n");
+
+	pdev_nr = status_name_to_id(attr->attr.name);
+	if (pdev_nr < 0)
+		out += status_show_not_ready(pdev_nr, out);
+	else
+		out += status_show_vhci(pdev_nr, out);
+
+	return out - s;
+}
+
+static ssize_t nports_show(struct device *dev, struct device_attribute *attr,
+			   char *out)
+{
+	char *s = out;
+
+	out += sprintf(out, "%d\n", VHCI_HC_PORTS * vhci_num_controllers);
 	return out - s;
 }
-static DEVICE_ATTR_RO(status);
+static DEVICE_ATTR_RO(nports);
 
 /* Sysfs entry to shutdown a virtual connection */
-static int vhci_port_disconnect(__u32 rhport)
+static int vhci_port_disconnect(struct vhci_hcd *vhci, __u32 rhport)
 {
-	struct vhci_device *vdev;
+	struct vhci_device *vdev = &vhci->vdev[rhport];
 	unsigned long flags;
 
 	usbip_dbg_vhci_sysfs("enter\n");
 
 	/* lock */
-	spin_lock_irqsave(&the_controller->lock, flags);
-
-	vdev = port_to_vdev(rhport);
-
+	spin_lock_irqsave(&vhci->lock, flags);
 	spin_lock(&vdev->ud.lock);
+
 	if (vdev->ud.status == VDEV_ST_NULL) {
 		pr_err("not connected %d\n", vdev->ud.status);
 
 		/* unlock */
 		spin_unlock(&vdev->ud.lock);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock_irqrestore(&vhci->lock, flags);
 
 		return -EINVAL;
 	}
 
 	/* unlock */
 	spin_unlock(&vdev->ud.lock);
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock_irqrestore(&vhci->lock, flags);
 
 	usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);
 
 	return 0;
 }
 
+static int valid_port(__u32 pdev_nr, __u32 rhport)
+{
+	if (pdev_nr >= vhci_num_controllers) {
+		pr_err("pdev %u\n", pdev_nr);
+		return 0;
+	}
+	if (rhport >= VHCI_HC_PORTS) {
+		pr_err("rhport %u\n", rhport);
+		return 0;
+	}
+	return 1;
+}
+
 static ssize_t store_detach(struct device *dev, struct device_attribute *attr,
 			    const char *buf, size_t count)
 {
-	int err;
-	__u32 rhport = 0;
+	__u32 port = 0, pdev_nr = 0, rhport = 0;
+	struct usb_hcd *hcd;
+	int ret;
 
-	if (sscanf(buf, "%u", &rhport) != 1)
+	if (kstrtoint(buf, 10, &port) < 0)
 		return -EINVAL;
 
-	/* check rhport */
-	if (rhport >= VHCI_NPORTS) {
-		dev_err(dev, "invalid port %u\n", rhport);
+	pdev_nr = port_to_pdev_nr(port);
+	rhport = port_to_rhport(port);
+
+	if (!valid_port(pdev_nr, rhport))
 		return -EINVAL;
+
+	hcd = platform_get_drvdata(*(vhci_pdevs + pdev_nr));
+	if (hcd == NULL) {
+		dev_err(dev, "port is not ready %u\n", port);
+		return -EAGAIN;
 	}
 
-	err = vhci_port_disconnect(rhport);
-	if (err < 0)
+	ret = vhci_port_disconnect(hcd_to_vhci(hcd), rhport);
+	if (ret < 0)
 		return -EINVAL;
 
 	usbip_dbg_vhci_sysfs("Leave\n");
@@ -135,16 +222,12 @@ static ssize_t store_detach(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR(detach, S_IWUSR, NULL, store_detach);
 
-/* Sysfs entry to establish a virtual connection */
-static int valid_args(__u32 rhport, enum usb_device_speed speed)
+static int valid_args(__u32 pdev_nr, __u32 rhport, enum usb_device_speed speed)
 {
-	/* check rhport */
-	if (rhport >= VHCI_NPORTS) {
-		pr_err("port %u\n", rhport);
-		return -EINVAL;
+	if (!valid_port(pdev_nr, rhport)) {
+		return 0;
 	}
 
-	/* check speed */
 	switch (speed) {
 	case USB_SPEED_LOW:
 	case USB_SPEED_FULL:
@@ -154,12 +237,13 @@ static int valid_args(__u32 rhport, enum usb_device_speed speed)
 	default:
 		pr_err("Failed attach request for unsupported USB speed: %s\n",
 			usb_speed_string(speed));
-		return -EINVAL;
+		return 0;
 	}
 
-	return 0;
+	return 1;
 }
 
+/* Sysfs entry to establish a virtual connection */
 /*
  * To start a new USB/IP attachment, a userland program needs to setup a TCP
  * connection and then write its socket descriptor with remote device
@@ -174,10 +258,12 @@ static int valid_args(__u32 rhport, enum usb_device_speed speed)
 static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 			    const char *buf, size_t count)
 {
-	struct vhci_device *vdev;
 	struct socket *socket;
 	int sockfd = 0;
-	__u32 rhport = 0, devid = 0, speed = 0;
+	__u32 port = 0, pdev_nr = 0, rhport = 0, devid = 0, speed = 0;
+	struct usb_hcd *hcd;
+	struct vhci_hcd *vhci;
+	struct vhci_device *vdev;
 	int err;
 	unsigned long flags;
 
@@ -187,16 +273,28 @@ static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 	 * @devid: unique device identifier in a remote host
 	 * @speed: usb device speed in a remote host
 	 */
-	if (sscanf(buf, "%u %u %u %u", &rhport, &sockfd, &devid, &speed) != 4)
+	if (sscanf(buf, "%u %u %u %u", &port, &sockfd, &devid, &speed) != 4)
 		return -EINVAL;
+	pdev_nr = port_to_pdev_nr(port);
+	rhport = port_to_rhport(port);
 
-	usbip_dbg_vhci_sysfs("rhport(%u) sockfd(%u) devid(%u) speed(%u)\n",
-			     rhport, sockfd, devid, speed);
+	usbip_dbg_vhci_sysfs("port(%u) pdev(%d) rhport(%u)\n",
+			     port, pdev_nr, rhport);
+	usbip_dbg_vhci_sysfs("sockfd(%u) devid(%u) speed(%u)\n",
+			     sockfd, devid, speed);
 
 	/* check received parameters */
-	if (valid_args(rhport, speed) < 0)
+	if (!valid_args(pdev_nr, rhport, speed))
 		return -EINVAL;
 
+	hcd = platform_get_drvdata(*(vhci_pdevs + pdev_nr));
+	if (hcd == NULL) {
+		dev_err(dev, "port %d is not ready\n", port);
+		return -EAGAIN;
+	}
+	vhci = hcd_to_vhci(hcd);
+	vdev = &vhci->vdev[rhport];
+
 	/* Extract socket from fd. */
 	socket = sockfd_lookup(sockfd, &err);
 	if (!socket)
@@ -205,14 +303,13 @@ static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 	/* now need lock until setting vdev status as used */
 
 	/* begin a lock */
-	spin_lock_irqsave(&the_controller->lock, flags);
-	vdev = port_to_vdev(rhport);
+	spin_lock_irqsave(&vhci->lock, flags);
 	spin_lock(&vdev->ud.lock);
 
 	if (vdev->ud.status != VDEV_ST_NULL) {
 		/* end of the lock */
 		spin_unlock(&vdev->ud.lock);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_unlock_irqrestore(&vhci->lock, flags);
 
 		sockfd_put(socket);
 
@@ -220,9 +317,10 @@ static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 		return -EINVAL;
 	}
 
-	dev_info(dev,
-		 "rhport(%u) sockfd(%d) devid(%u) speed(%u) speed_str(%s)\n",
-		 rhport, sockfd, devid, speed, usb_speed_string(speed));
+	dev_info(dev, "pdev(%u) rhport(%u) sockfd(%d)\n",
+		 pdev_nr, rhport, sockfd);
+	dev_info(dev, "devid(%u) speed(%u) speed_str(%s)\n",
+		 devid, speed, usb_speed_string(speed));
 
 	vdev->devid         = devid;
 	vdev->speed         = speed;
@@ -230,26 +328,92 @@ static ssize_t store_attach(struct device *dev, struct device_attribute *attr,
 	vdev->ud.status     = VDEV_ST_NOTASSIGNED;
 
 	spin_unlock(&vdev->ud.lock);
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_unlock_irqrestore(&vhci->lock, flags);
 	/* end the lock */
 
 	vdev->ud.tcp_rx = kthread_get_run(vhci_rx_loop, &vdev->ud, "vhci_rx");
 	vdev->ud.tcp_tx = kthread_get_run(vhci_tx_loop, &vdev->ud, "vhci_tx");
 
-	rh_port_connect(rhport, speed);
+	rh_port_connect(vdev, speed);
 
 	return count;
 }
 static DEVICE_ATTR(attach, S_IWUSR, NULL, store_attach);
 
-static struct attribute *dev_attrs[] = {
-	&dev_attr_status.attr,
-	&dev_attr_detach.attr,
-	&dev_attr_attach.attr,
-	&dev_attr_usbip_debug.attr,
-	NULL,
+#define MAX_STATUS_NAME 16
+
+struct status_attr {
+	struct device_attribute attr;
+	char name[MAX_STATUS_NAME+1];
 };
 
-const struct attribute_group dev_attr_group = {
-	.attrs = dev_attrs,
+static struct status_attr *status_attrs;
+
+static void set_status_attr(int id)
+{
+	struct status_attr *status;
+
+	status = status_attrs + id;
+	if (id == 0)
+		strcpy(status->name, "status");
+	else
+		snprintf(status->name, MAX_STATUS_NAME+1, "status.%d", id);
+	status->attr.attr.name = status->name;
+	status->attr.attr.mode = S_IRUGO;
+	status->attr.show = status_show;
+}
+
+static int init_status_attrs(void)
+{
+	int id;
+
+	status_attrs = kcalloc(vhci_num_controllers, sizeof(struct status_attr),
+			       GFP_KERNEL);
+	if (status_attrs == NULL)
+		return -ENOMEM;
+
+	for (id = 0; id < vhci_num_controllers; id++)
+		set_status_attr(id);
+
+	return 0;
+}
+
+static void finish_status_attrs(void)
+{
+	kfree(status_attrs);
+}
+
+struct attribute_group vhci_attr_group = {
+	.attrs = NULL,
 };
+
+int vhci_init_attr_group(void)
+{
+	struct attribute **attrs;
+	int ret, i;
+
+	attrs = kcalloc((vhci_num_controllers + 5), sizeof(struct attribute *),
+			GFP_KERNEL);
+	if (attrs == NULL)
+		return -ENOMEM;
+
+	ret = init_status_attrs();
+	if (ret) {
+		kfree(attrs);
+		return ret;
+	}
+	*attrs = &dev_attr_nports.attr;
+	*(attrs + 1) = &dev_attr_detach.attr;
+	*(attrs + 2) = &dev_attr_attach.attr;
+	*(attrs + 3) = &dev_attr_usbip_debug.attr;
+	for (i = 0; i < vhci_num_controllers; i++)
+		*(attrs + i + 4) = &((status_attrs + i)->attr.attr);
+	vhci_attr_group.attrs = attrs;
+	return 0;
+}
+
+void vhci_finish_attr_group(void)
+{
+	finish_status_attrs();
+	kfree(vhci_attr_group.attrs);
+}