0143-usb-redir-Don-t-delay-handling-of-open-events-to-a-b.patch

   1 From b89a0cc1ec9dbe30cbe002f12d487a52950da166 Mon Sep 17 00:00:00 2001
   2 From: Hans de Goede <hdegoede@redhat.com>
   3 Date: Thu, 23 Aug 2012 16:37:19 +0200
   4 Subject: [PATCH] usb-redir: Don't delay handling of open events to a bottom
   5  half
   6
   7 There is no need for this, and doing so means that a backend trying to
   8 write immediately after an open event will see qemu_chr_be_can_write
   9 returning 0, which not all backends handle well as there is no wakeup
  10 mechanism to detect when the frontend does become writable.
  11
  12 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  13 Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
  14 (cherry picked from commit ed9873bfbf145c084d039baab08c63b9d67e7bd3)
  15
  16 Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
  17 ---
  18  hw/usb/redirect.c | 100 +++++++++++++++++++++++++++++-------------------------
  19  1 file changed, 53 insertions(+), 47 deletions(-)
  20
  21 diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
  22 index 7f3719b..5cc3334 100644
  23 --- a/hw/usb/redirect.c
  24 +++ b/hw/usb/redirect.c
  25 @@ -79,8 +79,8 @@ struct USBRedirDevice {
  26      /* Data passed from chardev the fd_read cb to the usbredirparser read cb */
  27      const uint8_t *read_buf;
  28      int read_buf_size;
  29 -    /* For async handling of open/close */
  30 -    QEMUBH *open_close_bh;
  31 +    /* For async handling of close */
  32 +    QEMUBH *chardev_close_bh;
  33      /* To delay the usb attach in case of quick chardev close + open */
  34      QEMUTimer *attach_timer;
  35      int64_t next_attach_time;
  36 @@ -784,18 +784,11 @@ static int usbredir_handle_control(USBDevice *udev, USBPacket *p,
  37   * from within the USBDevice data / control packet callbacks and doing a
  38   * usb_detach from within these callbacks is not a good idea.
  39   *
  40 - * So we use a bh handler to take care of close events. We also handle
  41 - * open events from this callback to make sure that a close directly followed
  42 - * by an open gets handled in the right order.
  43 + * So we use a bh handler to take care of close events.
  44   */
  45 -static void usbredir_open_close_bh(void *opaque)
  46 +static void usbredir_chardev_close_bh(void *opaque)
  47  {
  48      USBRedirDevice *dev = opaque;
  49 -    uint32_t caps[USB_REDIR_CAPS_SIZE] = { 0, };
  50 -    char version[32];
  51 -
  52 -    strcpy(version, "qemu usb-redir guest ");
  53 -    pstrcat(version, sizeof(version), qemu_get_version());
  54
  55      usbredir_device_disconnect(dev);
  56
  57 @@ -803,36 +796,47 @@ static void usbredir_open_close_bh(void *opaque)
  58          usbredirparser_destroy(dev->parser);
  59          dev->parser = NULL;
  60      }
  61 +}
  62
  63 -    if (dev->cs->opened) {
  64 -        dev->parser = qemu_oom_check(usbredirparser_create());
  65 -        dev->parser->priv = dev;
  66 -        dev->parser->log_func = usbredir_log;
  67 -        dev->parser->read_func = usbredir_read;
  68 -        dev->parser->write_func = usbredir_write;
  69 -        dev->parser->hello_func = usbredir_hello;
  70 -        dev->parser->device_connect_func = usbredir_device_connect;
  71 -        dev->parser->device_disconnect_func = usbredir_device_disconnect;
  72 -        dev->parser->interface_info_func = usbredir_interface_info;
  73 -        dev->parser->ep_info_func = usbredir_ep_info;
  74 -        dev->parser->configuration_status_func = usbredir_configuration_status;
  75 -        dev->parser->alt_setting_status_func = usbredir_alt_setting_status;
  76 -        dev->parser->iso_stream_status_func = usbredir_iso_stream_status;
  77 -        dev->parser->interrupt_receiving_status_func =
  78 -            usbredir_interrupt_receiving_status;
  79 -        dev->parser->bulk_streams_status_func = usbredir_bulk_streams_status;
  80 -        dev->parser->control_packet_func = usbredir_control_packet;
  81 -        dev->parser->bulk_packet_func = usbredir_bulk_packet;
  82 -        dev->parser->iso_packet_func = usbredir_iso_packet;
  83 -        dev->parser->interrupt_packet_func = usbredir_interrupt_packet;
  84 -        dev->read_buf = NULL;
  85 -        dev->read_buf_size = 0;
  86 +static void usbredir_chardev_open(USBRedirDevice *dev)
  87 +{
  88 +    uint32_t caps[USB_REDIR_CAPS_SIZE] = { 0, };
  89 +    char version[32];
  90
  91 -        usbredirparser_caps_set_cap(caps, usb_redir_cap_connect_device_version);
  92 -        usbredirparser_caps_set_cap(caps, usb_redir_cap_filter);
  93 -        usbredirparser_init(dev->parser, version, caps, USB_REDIR_CAPS_SIZE, 0);
  94 -        usbredirparser_do_write(dev->parser);
  95 -    }
  96 +    /* Make sure any pending closes are handled (no-op if none pending) */
  97 +    usbredir_chardev_close_bh(dev);
  98 +    qemu_bh_cancel(dev->chardev_close_bh);
  99 +
 100 +    strcpy(version, "qemu usb-redir guest ");
 101 +    pstrcat(version, sizeof(version), qemu_get_version());
 102 +
 103 +    dev->parser = qemu_oom_check(usbredirparser_create());
 104 +    dev->parser->priv = dev;
 105 +    dev->parser->log_func = usbredir_log;
 106 +    dev->parser->read_func = usbredir_read;
 107 +    dev->parser->write_func = usbredir_write;
 108 +    dev->parser->hello_func = usbredir_hello;
 109 +    dev->parser->device_connect_func = usbredir_device_connect;
 110 +    dev->parser->device_disconnect_func = usbredir_device_disconnect;
 111 +    dev->parser->interface_info_func = usbredir_interface_info;
 112 +    dev->parser->ep_info_func = usbredir_ep_info;
 113 +    dev->parser->configuration_status_func = usbredir_configuration_status;
 114 +    dev->parser->alt_setting_status_func = usbredir_alt_setting_status;
 115 +    dev->parser->iso_stream_status_func = usbredir_iso_stream_status;
 116 +    dev->parser->interrupt_receiving_status_func =
 117 +        usbredir_interrupt_receiving_status;
 118 +    dev->parser->bulk_streams_status_func = usbredir_bulk_streams_status;
 119 +    dev->parser->control_packet_func = usbredir_control_packet;
 120 +    dev->parser->bulk_packet_func = usbredir_bulk_packet;
 121 +    dev->parser->iso_packet_func = usbredir_iso_packet;
 122 +    dev->parser->interrupt_packet_func = usbredir_interrupt_packet;
 123 +    dev->read_buf = NULL;
 124 +    dev->read_buf_size = 0;
 125 +
 126 +    usbredirparser_caps_set_cap(caps, usb_redir_cap_connect_device_version);
 127 +    usbredirparser_caps_set_cap(caps, usb_redir_cap_filter);
 128 +    usbredirparser_init(dev->parser, version, caps, USB_REDIR_CAPS_SIZE, 0);
 129 +    usbredirparser_do_write(dev->parser);
 130  }
 131
 132  static void usbredir_do_attach(void *opaque)
 133 @@ -856,13 +860,13 @@ static int usbredir_chardev_can_read(void *opaque)
 134  {
 135      USBRedirDevice *dev = opaque;
 136
 137 -    if (dev->parser) {
 138 -        /* usbredir_parser_do_read will consume *all* data we give it */
 139 -        return 1024 * 1024;
 140 -    } else {
 141 -        /* usbredir_open_close_bh hasn't handled the open event yet */
 142 +    if (!dev->parser) {
 143 +        WARNING("chardev_can_read called on non open chardev!\n");
 144          return 0;
 145      }
 146 +
 147 +    /* usbredir_parser_do_read will consume *all* data we give it */
 148 +    return 1024 * 1024;
 149  }
 150
 151  static void usbredir_chardev_read(void *opaque, const uint8_t *buf, int size)
 152 @@ -886,8 +890,10 @@ static void usbredir_chardev_event(void *opaque, int event)
 153
 154      switch (event) {
 155      case CHR_EVENT_OPENED:
 156 +        usbredir_chardev_open(dev);
 157 +        break;
 158      case CHR_EVENT_CLOSED:
 159 -        qemu_bh_schedule(dev->open_close_bh);
 160 +        qemu_bh_schedule(dev->chardev_close_bh);
 161          break;
 162      }
 163  }
 164 @@ -917,7 +923,7 @@ static int usbredir_initfn(USBDevice *udev)
 165          }
 166      }
 167
 168 -    dev->open_close_bh = qemu_bh_new(usbredir_open_close_bh, dev);
 169 +    dev->chardev_close_bh = qemu_bh_new(usbredir_chardev_close_bh, dev);
 170      dev->attach_timer = qemu_new_timer_ms(vm_clock, usbredir_do_attach, dev);
 171
 172      QTAILQ_INIT(&dev->asyncq);
 173 @@ -957,7 +963,7 @@ static void usbredir_handle_destroy(USBDevice *udev)
 174      qemu_chr_fe_close(dev->cs);
 175      qemu_chr_delete(dev->cs);
 176      /* Note must be done after qemu_chr_close, as that causes a close event */
 177 -    qemu_bh_delete(dev->open_close_bh);
 178 +    qemu_bh_delete(dev->chardev_close_bh);
 179
 180      qemu_del_timer(dev->attach_timer);
 181      qemu_free_timer(dev->attach_timer);
 182 --
 183 1.7.12.1
 184