Re: [Qemu-devel] [usb] call destroy for usb devices upon removal from guest

[Lonnie Mendez <lmendez19@austin.rr.com>]

[-- Attachment #1: Type: text/plain, Size: 864 bytes --]

On Tue, 2006-07-18 at 23:46 +0200, Fabrice Bellard wrote:
> Lonnie Mendez wrote:
> > lo list.  I have found the old diff to be incorrect on many levels.  New
> > diff has additionally cleanup code for the linux redirector.  Please see
> > the attached patch for solution.
> 
> Forget my last comment - I understand the problem now. I think it was a 
> bad idea to use 'usb_reset' to destroy the usb device. Ideally a 
> specific method should be added because it has no relation with the USB 
> protocol (it is used to clear resources and it is perfectly possible 
> that a given device can be inserted, removed and inserted again without 
> having been destroyed). Another point is that the unused message 
> 'USB_DESTROY' should be... destroyed.

   Attached is a new diff that implements your suggestions.  I have
compiled and run tested the patch against cvs.

[-- Attachment #2: qemu-usb-cleanup2.diff --]
[-- Type: text/x-patch, Size: 6733 bytes --]

--- qemu/hw/usb.h	2006-06-26 16:00:51.000000000 -0500
+++ qemu/hw/usb.h	2006-07-18 21:51:17.651436624 -0500
@@ -29,7 +29,6 @@
 #define USB_MSG_ATTACH   0x100
 #define USB_MSG_DETACH   0x101
 #define USB_MSG_RESET    0x102
-#define USB_MSG_DESTROY  0x103
 
 #define USB_RET_NODEV  (-1) 
 #define USB_RET_NAK    (-2)
@@ -117,12 +116,14 @@
     int (*handle_packet)(USBDevice *dev, int pid, 
                          uint8_t devaddr, uint8_t devep,
                          uint8_t *data, int len);
+    void (*handle_destroy)(USBDevice *dev);
+
     int speed;
     
     /* The following fields are used by the generic USB device
        layer. They are here just to avoid creating a new structure for
        them. */
-    void (*handle_reset)(USBDevice *dev, int destroy);
+    void (*handle_reset)(USBDevice *dev);
     int (*handle_control)(USBDevice *dev, int request, int value,
                           int index, int length, uint8_t *data);
     int (*handle_data)(USBDevice *dev, int pid, uint8_t devep,
--- qemu/hw/usb.c	2006-05-25 18:58:51.000000000 -0500
+++ qemu/hw/usb.c	2006-07-18 21:43:26.741025888 -0500
@@ -55,10 +55,7 @@
         s->remote_wakeup = 0;
         s->addr = 0;
         s->state = USB_STATE_DEFAULT;
-        s->handle_reset(s, 0);
-        break;
-    case USB_MSG_DESTROY:
-        s->handle_reset(s, 1);
+        s->handle_reset(s);
         break;
     case USB_TOKEN_SETUP:
         if (s->state < USB_STATE_DEFAULT || devaddr != s->addr)
--- qemu/hw/usb-hid.c	2006-06-26 16:00:51.000000000 -0500
+++ qemu/hw/usb-hid.c	2006-07-18 21:52:39.754954992 -0500
@@ -323,16 +323,10 @@
     return l;
 }
 
-static void usb_mouse_handle_reset(USBDevice *dev, int destroy)
+static void usb_mouse_handle_reset(USBDevice *dev)
 {
     USBMouseState *s = (USBMouseState *)dev;
 
-    if (destroy) {
-        qemu_add_mouse_event_handler(NULL, NULL, 0);
-        qemu_free(s);
-        return;
-    }
-
     s->dx = 0;
     s->dy = 0;
     s->dz = 0;
@@ -506,6 +500,14 @@
     return ret;
 }
 
+static void usb_mouse_handle_destroy(USBDevice *dev)
+{
+    USBMouseState *s = (USBMouseState *)dev;
+
+    qemu_add_mouse_event_handler(NULL, NULL, 0);
+    qemu_free(s);
+}
+
 USBDevice *usb_tablet_init(void)
 {
     USBMouseState *s;
@@ -519,6 +521,7 @@
     s->dev.handle_reset = usb_mouse_handle_reset;
     s->dev.handle_control = usb_mouse_handle_control;
     s->dev.handle_data = usb_mouse_handle_data;
+    s->dev.handle_destroy = usb_mouse_handle_destroy;
     s->kind = USB_TABLET;
 
     pstrcpy(s->dev.devname, sizeof(s->dev.devname), "QEMU USB Tablet");
@@ -539,6 +542,7 @@
     s->dev.handle_reset = usb_mouse_handle_reset;
     s->dev.handle_control = usb_mouse_handle_control;
     s->dev.handle_data = usb_mouse_handle_data;
+    s->dev.handle_destroy = usb_mouse_handle_destroy;
     s->kind = USB_MOUSE;
 
     pstrcpy(s->dev.devname, sizeof(s->dev.devname), "QEMU USB Mouse");
--- qemu/hw/usb-hub.c	2006-06-26 16:00:51.000000000 -0500
+++ qemu/hw/usb-hub.c	2006-07-18 21:53:24.391169256 -0500
@@ -199,11 +199,9 @@
     }
 }
 
-static void usb_hub_handle_reset(USBDevice *dev, int destroy)
+static void usb_hub_handle_reset(USBDevice *dev)
 {
     /* XXX: do it */
-    if (destroy)
-        qemu_free(dev);
 }
 
 static int usb_hub_handle_control(USBDevice *dev, int request, int value,
@@ -525,6 +523,13 @@
     return usb_generic_handle_packet(dev, pid, devaddr, devep, data, len);
 }
 
+static void usb_hub_handle_destroy(USBDevice *dev)
+{
+    USBHubState *s = (USBHubState *)dev;
+
+    qemu_free(s);
+}
+
 USBDevice *usb_hub_init(int nb_ports)
 {
     USBHubState *s;
@@ -543,6 +548,7 @@
     s->dev.handle_reset = usb_hub_handle_reset;
     s->dev.handle_control = usb_hub_handle_control;
     s->dev.handle_data = usb_hub_handle_data;
+    s->dev.handle_destroy = usb_hub_handle_destroy;
 
     pstrcpy(s->dev.devname, sizeof(s->dev.devname), "QEMU USB Hub");
 
--- qemu/hw/usb-msd.c	2006-06-26 16:00:51.000000000 -0500
+++ qemu/hw/usb-msd.c	2006-07-18 21:54:25.569868680 -0500
@@ -112,16 +112,12 @@
     s->mode = USB_MSDM_CSW;
 }
 
-static void usb_msd_handle_reset(USBDevice *dev, int destroy)
+static void usb_msd_handle_reset(USBDevice *dev)
 {
     MSDState *s = (MSDState *)dev;
 
     DPRINTF("Reset\n");
     s->mode = USB_MSDM_CBW;
-    if (destroy) {
-        scsi_disk_destroy(s->scsi_dev);
-        qemu_free(s);
-    }
 }
 
 static int usb_msd_handle_control(USBDevice *dev, int request, int value,
@@ -369,6 +365,13 @@
     return ret;
 }
 
+static void usb_msd_handle_destroy(USBDevice *dev)
+{
+    MSDState *s = (MSDState *)dev;
+
+    scsi_disk_destroy(s->scsi_dev);
+    qemu_free(s);
+}
 
 USBDevice *usb_msd_init(const char *filename)
 {
@@ -388,11 +391,12 @@
     s->dev.handle_reset = usb_msd_handle_reset;
     s->dev.handle_control = usb_msd_handle_control;
     s->dev.handle_data = usb_msd_handle_data;
+    s->dev.handle_destroy = usb_msd_handle_destroy;
 
     snprintf(s->dev.devname, sizeof(s->dev.devname), "QEMU USB MSD(%.16s)",
              filename);
 
     s->scsi_dev = scsi_disk_init(bdrv, usb_msd_command_complete, s);
-    usb_msd_handle_reset((USBDevice *)s, 0);
+    usb_msd_handle_reset((USBDevice *)s);
     return (USBDevice *)s;
 }
--- qemu/usb-linux.c	2006-06-26 16:00:51.000000000 -0500
+++ qemu/usb-linux.c	2006-07-18 21:54:01.039597848 -0500
@@ -57,7 +57,7 @@
     int fd;
 } USBHostDevice;
 
-static void usb_host_handle_reset(USBDevice *dev, int destroy)
+static void usb_host_handle_reset(USBDevice *dev)
 {
 #if 0
     USBHostDevice *s = (USBHostDevice *)dev;
@@ -67,6 +67,15 @@
 #endif
 } 
 
+static void usb_host_handle_destroy(USBDevice *dev)
+{
+    USBHostDevice *s = (USBHostDevice *)dev;
+
+    if (s->fd >= 0)
+        close(s->fd);
+    qemu_free(s);
+}
+
 static int usb_host_handle_control(USBDevice *dev,
                                    int request,
                                    int value,
@@ -235,6 +244,7 @@
     dev->dev.handle_reset = usb_host_handle_reset;
     dev->dev.handle_control = usb_host_handle_control;
     dev->dev.handle_data = usb_host_handle_data;
+    dev->dev.handle_destroy = usb_host_handle_destroy;
 
     if (product_name[0] == '\0')
         snprintf(dev->dev.devname, sizeof(dev->dev.devname),
--- qemu/vl.c	2006-07-17 03:16:38.000000000 -0500
+++ qemu/vl.c	2006-07-18 21:51:55.298713368 -0500
@@ -3781,6 +3781,7 @@
 {
     USBPort *port;
     USBPort **lastp;
+    USBDevice *dev;
     int bus_num, addr;
     const char *p;
 
@@ -3805,8 +3806,10 @@
     if (!port)
         return -1;
 
+    dev = port->dev;
     *lastp = port->next;
     usb_attach(port, NULL);
+    dev->handle_destroy(dev);
     port->next = free_usb_ports;
     free_usb_ports = port;
     return 0;