husb: support for USB host device auto connect (Max Krasnyansky)

QEMU can now automatically grab host USB devices that match the filter.
For now I just extended 'host:X.Y' and 'host:VID:PID' syntax to handle
wildcards. So for example if you do something like
   usb_add host:5.*
QEMU will automatically grab any non-hub device with host address 5.*.

Same with the 'host:PID:*', we grab any device that matches PID.

Filtering itself is very generic so we can probably add more elaborate
syntax like 'host:BUS.ADDR:VID:PID'. So that we can do 'host:5.*:6000:*'.

Anyway, it's implemented using a periodic timer that scans host devices
and grabs those that match the filter. Timer is started when the first
filter is added.

We now keep the list of all host devices that we grabbed to make sure that
we do not grab the same device twice.

btw It's currently possible to grab the same host device more than once.
ie You can just do "usb_add host:1.1" more than once, which of course does
not work. So this patch fixes that issue too.

Along with auto disconnect patch that I send a minute ago the setup is very
seamless now. You can just allocate some usb ports to the VMs and plug/unplug
devices at any time.

Signed-off-by: Max Krasnyansky <maxk@kernel.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5048 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/usb-linux.c b/usb-linux.c
index 0023c1d..622255c 100644
--- a/usb-linux.c
+++ b/usb-linux.c
@@ -3,6 +3,9 @@
  *
  * Copyright (c) 2005 Fabrice Bellard
  *
+ * Support for host device auto connect & disconnect
+ *       Copyright (c) 2008 Max Krasnyansky
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
@@ -67,6 +70,8 @@
     uint8_t type;
 };
 
+
+
 /* FIXME: move USBPacket to PendingURB */
 typedef struct USBHostDevice {
     USBDevice dev;
@@ -78,9 +83,51 @@
     uint8_t descr[1024];
     int descr_len;
     int urbs_ready;
+
     QEMUTimer *timer;
+
+    /* Host side address */
+    int bus_num;
+    int addr;
+
+    struct USBHostDevice *next;
 } USBHostDevice;
 
+static USBHostDevice *hostdev_list;
+
+static void hostdev_link(USBHostDevice *dev)
+{
+    dev->next = hostdev_list;
+    hostdev_list = dev;
+}
+
+static void hostdev_unlink(USBHostDevice *dev)
+{
+    USBHostDevice *pdev = hostdev_list;
+    USBHostDevice **prev = &hostdev_list;
+
+    while (pdev) {
+	if (pdev == dev) {
+            *prev = dev->next;
+            return;
+        }
+
+        prev = &pdev->next;
+        pdev = pdev->next;
+    }
+}
+
+static USBHostDevice *hostdev_find(int bus_num, int addr)
+{
+    USBHostDevice *s = hostdev_list;
+    while (s) {
+        if (s->bus_num == bus_num && s->addr == addr)
+            return s;
+        s = s->next;
+    }
+    return NULL;
+}
+
 typedef struct PendingURB {
     struct usbdevfs_urb *urb;
     int status;
@@ -238,6 +285,8 @@
 
     qemu_del_timer(s->timer);
 
+    hostdev_unlink(s);
+
     if (s->fd >= 0)
         close(s->fd);
 
@@ -619,32 +668,26 @@
     qemu_mod_timer(s->timer, qemu_get_clock(rt_clock) + 1000);
 }
 
-/* XXX: exclude high speed devices or implement EHCI */
-USBDevice *usb_host_device_open(const char *devname)
+static USBDevice *usb_host_device_open_addr(int bus_num, int addr, const char *prod_name)
 {
     int fd = -1, ret;
     USBHostDevice *dev = NULL;
     struct usbdevfs_connectinfo ci;
     char buf[1024];
-    int bus_num, addr;
-    char product_name[PRODUCT_NAME_SZ];
-
-    if (usb_host_find_device(&bus_num, &addr,
-                             product_name, sizeof(product_name),
-                             devname) < 0)
-        return NULL;
-
 
     dev = qemu_mallocz(sizeof(USBHostDevice));
     if (!dev)
         goto fail;
 
+    dev->bus_num = bus_num;
+    dev->addr = addr;
+
     dev->timer = qemu_new_timer(rt_clock, usb_host_device_check, (void *) dev);
     if (!dev->timer)
 	goto fail;
 
 #ifdef DEBUG
-    printf("usb_host_device_open %s\n", devname);
+    printf("usb_host_device_open %d.%d\n", bus_num, addr);
 #endif
 
     snprintf(buf, sizeof(buf), USBDEVFS_PATH "/%03d/%03d",
@@ -704,12 +747,12 @@
     dev->dev.handle_data = usb_host_handle_data;
     dev->dev.handle_destroy = usb_host_handle_destroy;
 
-    if (product_name[0] == '\0')
+    if (!prod_name || prod_name[0] == '\0')
         snprintf(dev->dev.devname, sizeof(dev->dev.devname),
-                 "host:%s", devname);
+                 "host:%d.%d", bus_num, addr);
     else
         pstrcpy(dev->dev.devname, sizeof(dev->dev.devname),
-                product_name);
+                prod_name);
 
 #ifdef USE_ASYNCIO
     /* set up the signal handlers */
@@ -735,8 +778,11 @@
     /* Start the timer to detect disconnect */
     qemu_mod_timer(dev->timer, qemu_get_clock(rt_clock) + 1000);
 
+    hostdev_link(dev);
+
     dev->urbs_ready = 0;
     return (USBDevice *)dev;
+
 fail:
     if (dev) {
 	if (dev->timer)
@@ -747,6 +793,24 @@
     return NULL;
 }
 
+USBDevice *usb_host_device_open(const char *devname)
+{
+    int bus_num, addr;
+    char product_name[PRODUCT_NAME_SZ];
+
+    if (usb_host_find_device(&bus_num, &addr,
+                             product_name, sizeof(product_name),
+                             devname) < 0)
+        return NULL;
+
+     if (hostdev_find(bus_num, addr)) {
+        printf("host usb device %d.%d is already open\n", bus_num, addr);
+        return NULL;
+     }
+
+    return usb_host_device_open_addr(bus_num, addr, product_name);
+}
+ 
 static int get_tag_value(char *buf, int buf_size,
                          const char *str, const char *tag,
                          const char *stopchars)
@@ -846,6 +910,108 @@
     return ret;
 }
 
+struct USBAutoFilter {
+    struct USBAutoFilter *next;
+    int bus_num;
+    int addr;
+    int vendor_id;
+    int product_id;
+};
+
+static QEMUTimer *usb_auto_timer;
+static struct USBAutoFilter *usb_auto_filter;
+
+static int usb_host_auto_scan(void *opaque, int bus_num, int addr,
+                     int class_id, int vendor_id, int product_id,
+                     const char *product_name, int speed)
+{
+    struct USBAutoFilter *f;
+    struct USBDevice *dev;
+
+    /* Ignore hubs */
+    if (class_id == 9)
+        return 0;
+
+    for (f = usb_auto_filter; f; f = f->next) {
+        // printf("Auto match: bus_num %d addr %d vid %d pid %d\n",
+	//    bus_num, addr, vendor_id, product_id);
+
+	if (f->bus_num >= 0 && f->bus_num != bus_num)
+            continue;
+
+	if (f->addr >= 0 && f->addr != addr)
+            continue;
+
+	if (f->vendor_id >= 0 && f->vendor_id != vendor_id)
+            continue;
+
+	if (f->product_id >= 0 && f->product_id != product_id)
+            continue;
+
+        /* We got a match */
+
+        /* Allredy attached ? */
+        if (hostdev_find(bus_num, addr))
+            return 0;
+
+        printf("Auto open: bus_num %d addr %d\n", bus_num, addr);
+
+	dev = usb_host_device_open_addr(bus_num, addr, product_name);
+	if (dev)
+	    usb_device_add_dev(dev);
+    }
+
+    return 0;
+}
+
+static void usb_host_auto_timer(void *unused)
+{
+    usb_host_scan(NULL, usb_host_auto_scan);
+    qemu_mod_timer(usb_auto_timer, qemu_get_clock(rt_clock) + 2000);
+}
+
+/*
+ * Add autoconnect filter
+ * -1 means 'any' (device, vendor, etc)
+ */
+static void usb_host_auto_add(int bus_num, int addr, int vendor_id, int product_id)
+{
+    struct USBAutoFilter *f = qemu_mallocz(sizeof(*f));
+    if (!f) {
+        printf("Failed to allocate auto filter\n");
+	return;
+    }
+
+    f->bus_num = bus_num;
+    f->addr    = addr;
+    f->vendor_id  = vendor_id;
+    f->product_id = product_id;
+
+    if (!usb_auto_filter) {
+        /*
+         * First entry. Init and start the monitor.
+         * Right now we're using timer to check for new devices.
+         * If this turns out to be too expensive we can move that into a 
+         * separate thread.
+         */
+	usb_auto_timer = qemu_new_timer(rt_clock, usb_host_auto_timer, NULL);
+	if (!usb_auto_timer) {
+            printf("Failed to allocate timer\n");
+            qemu_free(f);
+            return;
+        }
+
+        /* Check for new devices every two seconds */
+        qemu_mod_timer(usb_auto_timer, qemu_get_clock(rt_clock) + 2000);
+    }
+
+    printf("Auto filter: bus_num %d addr %d vid %d pid %d\n",
+	bus_num, addr, vendor_id, product_id);
+
+    f->next = usb_auto_filter;
+    usb_auto_filter = f;
+}
+
 typedef struct FindDeviceState {
     int vendor_id;
     int product_id;
@@ -887,6 +1053,12 @@
     p = strchr(devname, '.');
     if (p) {
         *pbus_num = strtoul(devname, NULL, 0);
+
+        if (*(p + 1) == '*') {
+            usb_host_auto_add(*pbus_num, -1, -1, -1);
+	    return -1;
+	}
+
         *paddr = strtoul(p + 1, NULL, 0);
         fs.bus_num = *pbus_num;
         fs.addr = *paddr;
@@ -898,6 +1070,12 @@
     p = strchr(devname, ':');
     if (p) {
         fs.vendor_id = strtoul(devname, NULL, 16);
+
+        if (*(p + 1) == '*') {
+            usb_host_auto_add(-1, -1, fs.vendor_id, -1);
+	    return -1;
+	}
+
         fs.product_id = strtoul(p + 1, NULL, 16);
         ret = usb_host_scan(&fs, usb_host_find_device_scan);
         if (ret) {
@@ -996,6 +1174,9 @@
     usb_host_scan(NULL, usb_host_info_device);
 }
 
+
+
+
 #else
 
 void usb_host_info(void)