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>

drivers/usb/usbip/Kconfig

@@ -24,6 +24,27 @@ config USBIP_VHCI_HCD
 	  To compile this driver as a module, choose M here: the
 	  module will be called vhci-hcd.
 
+config USBIP_VHCI_HC_PORTS
+	int "Number of ports per USB/IP virtual host controller"
+	range 1 31
+	default 8
+	depends on USBIP_VHCI_HCD
+	---help---
+	  To increase number of ports available for USB/IP virtual
+	  host controller driver, this defines number of ports per
+	  USB/IP virtual host controller.
+
+config USBIP_VHCI_NR_HCS
+	int "Number of USB/IP virtual host controllers"
+	range 1 128
+	default 1
+	depends on USBIP_VHCI_HCD
+	---help---
+	  To increase number of ports available for USB/IP virtual
+	  host controller driver, this defines number of USB/IP
+	  virtual host controllers as if adding physical host
+	  controllers.
+
 config USBIP_HOST
 	tristate "Host driver"
 	depends on USBIP_CORE && USB

drivers/usb/usbip/vhci.h

 /*
  * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ * Copyright (C) 2015 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
@@ -72,13 +73,25 @@ struct vhci_unlink {
 };
 
 /* Number of supported ports. Value has an upperbound of USB_MAXCHILDREN */
-#define VHCI_NPORTS 8
+#ifdef CONFIG_USBIP_VHCI_HC_PORTS
+#define VHCI_HC_PORTS CONFIG_USBIP_VHCI_HC_PORTS
+#else
+#define VHCI_HC_PORTS 8
+#endif
+
+#ifdef CONFIG_USBIP_VHCI_NR_HCS
+#define VHCI_NR_HCS CONFIG_USBIP_VHCI_NR_HCS
+#else
+#define VHCI_NR_HCS 1
+#endif
+
+#define MAX_STATUS_NAME 16
 
 /* for usb_bus.hcpriv */
 struct vhci_hcd {
 	spinlock_t lock;
 
-	u32 port_status[VHCI_NPORTS];
+	u32 port_status[VHCI_HC_PORTS];
 
 	unsigned resuming:1;
 	unsigned long re_timeout;
@@ -90,14 +103,19 @@ struct vhci_hcd {
 	 * wIndex shows the port number and begins from 1.
 	 * But, the index of this array begins from 0.
 	 */
-	struct vhci_device vdev[VHCI_NPORTS];
+	struct vhci_device vdev[VHCI_HC_PORTS];
 };
 
-extern struct vhci_hcd *the_controller;
-extern const struct attribute_group dev_attr_group;
+extern int vhci_num_controllers;
+extern struct platform_device **vhci_pdevs;
+extern struct attribute_group vhci_attr_group;
 
 /* vhci_hcd.c */
-void rh_port_connect(int rhport, enum usb_device_speed speed);
+void rh_port_connect(struct vhci_device *vdev, enum usb_device_speed speed);
+
+/* vhci_sysfs.c */
+int vhci_init_attr_group(void);
+void vhci_finish_attr_group(void);
 
 /* vhci_rx.c */
 struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum);
@@ -106,9 +124,14 @@ int vhci_rx_loop(void *data);
 /* vhci_tx.c */
 int vhci_tx_loop(void *data);
 
-static inline struct vhci_device *port_to_vdev(__u32 port)
+static inline __u32 port_to_rhport(__u32 port)
+{
+	return port % VHCI_HC_PORTS;
+}
+
+static inline int port_to_pdev_nr(__u32 port)
 {
-	return &the_controller->vdev[port];
+	return port / VHCI_HC_PORTS;
 }
 
 static inline struct vhci_hcd *hcd_to_vhci(struct usb_hcd *hcd)
@@ -116,14 +139,25 @@ static inline struct vhci_hcd *hcd_to_vhci(struct usb_hcd *hcd)
 	return (struct vhci_hcd *) (hcd->hcd_priv);
 }
 
+static inline struct device *hcd_dev(struct usb_hcd *hcd)
+{
+	return (hcd)->self.controller;
+}
+
+static inline const char *hcd_name(struct usb_hcd *hcd)
+{
+	return (hcd)->self.bus_name;
+}
+
 static inline struct usb_hcd *vhci_to_hcd(struct vhci_hcd *vhci)
 {
 	return container_of((void *) vhci, struct usb_hcd, hcd_priv);
 }
 
-static inline struct device *vhci_dev(struct vhci_hcd *vhci)
+static inline struct vhci_hcd *vdev_to_vhci(struct vhci_device *vdev)
 {
-	return vhci_to_hcd(vhci)->self.controller;
+	return container_of(
+			(void *)(vdev - vdev->rhport), struct vhci_hcd, vdev);
 }
 
 #endif /* __USBIP_VHCI_H */

drivers/usb/usbip/vhci_rx.c

@@ -70,6 +70,7 @@ struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum)
 static void vhci_recv_ret_submit(struct vhci_device *vdev,
 				 struct usbip_header *pdu)
 {
+	struct vhci_hcd *vhci = vdev_to_vhci(vdev);
 	struct usbip_device *ud = &vdev->ud;
 	struct urb *urb;
 	unsigned long flags;
@@ -81,7 +82,7 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
 	if (!urb) {
 		pr_err("cannot find a urb of seqnum %u\n", pdu->base.seqnum);
 		pr_info("max seqnum %d\n",
-			atomic_read(&the_controller->seqnum));
+			atomic_read(&vhci->seqnum));
 		usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 		return;
 	}
@@ -105,11 +106,11 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
 
 	usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
 
-	spin_lock_irqsave(&the_controller->lock, flags);
-	usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
-	spin_unlock_irqrestore(&the_controller->lock, flags);
+	spin_lock_irqsave(&vhci->lock, flags);
+	usb_hcd_unlink_urb_from_ep(vhci_to_hcd(vhci), urb);
+	spin_unlock_irqrestore(&vhci->lock, flags);
 
-	usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
+	usb_hcd_giveback_urb(vhci_to_hcd(vhci), urb, urb->status);
 
 	usbip_dbg_vhci_rx("Leave\n");
 }
@@ -142,6 +143,7 @@ static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev,
 static void vhci_recv_ret_unlink(struct vhci_device *vdev,
 				 struct usbip_header *pdu)
 {
+	struct vhci_hcd *vhci = vdev_to_vhci(vdev);
 	struct vhci_unlink *unlink;
 	struct urb *urb;
 	unsigned long flags;
@@ -174,12 +176,11 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
 		urb->status = pdu->u.ret_unlink.status;
 		pr_info("urb->status %d\n", urb->status);
 
-		spin_lock_irqsave(&the_controller->lock, flags);
-		usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
-		spin_unlock_irqrestore(&the_controller->lock, flags);
+		spin_lock_irqsave(&vhci->lock, flags);
+		usb_hcd_unlink_urb_from_ep(vhci_to_hcd(vhci), urb);
+		spin_unlock_irqrestore(&vhci->lock, flags);
 
-		usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
-				     urb->status);
+		usb_hcd_giveback_urb(vhci_to_hcd(vhci), urb, urb->status);
 	}
 
 	kfree(unlink);