target/linux/brcm2708/patches-4.14/950-0369-staging-bcm2835-camera-Remove-bulk_mutex-as-it-is-no.patch

   1 From 5d8eefe0b0b10b346c76cda1c99bceca33d66aac Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.org>
   3 Date: Thu, 10 May 2018 12:42:09 -0700
   4 Subject: [PATCH 369/454] staging: bcm2835-camera: Remove bulk_mutex as it is
   5  not required
   6
   7 commit 71fcbc4740ab24c5208a24cf48a8190dc8f5d9ae upstream.
   8
   9 There is no requirement to serialise bulk transfers as that is all
  10 done in VCHI, and if a second MMAL_MSG_TYPE_BUFFER_TO_HOST happened
  11 before the VCHI_CALLBACK_BULK_RECEIVED, then the service_callback
  12 thread is deadlocked.
  13
  14 Remove the bulk_mutex so that multiple receives can be scheduled at a
  15 time.
  16
  17 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
  18 Signed-off-by: Eric Anholt <eric@anholt.net>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20 ---
  21  .../vc04_services/bcm2835-camera/mmal-vchiq.c | 48 +------------------
  22  1 file changed, 1 insertion(+), 47 deletions(-)
  23
  24 --- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
  25 +++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
  26 @@ -165,9 +165,6 @@ struct vchiq_mmal_instance {
  27         /* ensure serialised access to service */
  28         struct mutex vchiq_mutex;
  29
  30 -       /* ensure serialised access to bulk operations */
  31 -       struct mutex bulk_mutex;
  32 -
  33         /* vmalloc page to receive scratch bulk xfers into */
  34         void *bulk_scratch;
  35
  36 @@ -335,13 +332,6 @@ static int bulk_receive(struct vchiq_mma
  37         unsigned long flags = 0;
  38         int ret;
  39
  40 -       /* bulk mutex stops other bulk operations while we have a
  41 -        * receive in progress - released in callback
  42 -        */
  43 -       ret = mutex_lock_interruptible(&instance->bulk_mutex);
  44 -       if (ret != 0)
  45 -               return ret;
  46 -
  47         rd_len = msg->u.buffer_from_host.buffer_header.length;
  48
  49         /* take buffer from queue */
  50 @@ -360,8 +350,6 @@ static int bulk_receive(struct vchiq_mma
  51                  * waiting bulk receive?
  52                  */
  53
  54 -               mutex_unlock(&instance->bulk_mutex);
  55 -
  56                 return -EINVAL;
  57         }
  58
  59 @@ -402,11 +390,6 @@ static int bulk_receive(struct vchiq_mma
  60
  61         vchi_service_release(instance->handle);
  62
  63 -       if (ret != 0) {
  64 -               /* callback will not be clearing the mutex */
  65 -               mutex_unlock(&instance->bulk_mutex);
  66 -       }
  67 -
  68         return ret;
  69  }
  70
  71 @@ -416,13 +399,6 @@ static int dummy_bulk_receive(struct vch
  72  {
  73         int ret;
  74
  75 -       /* bulk mutex stops other bulk operations while we have a
  76 -        * receive in progress - released in callback
  77 -        */
  78 -       ret = mutex_lock_interruptible(&instance->bulk_mutex);
  79 -       if (ret != 0)
  80 -               return ret;
  81 -
  82         /* zero length indicates this was a dummy transfer */
  83         msg_context->u.bulk.buffer_used = 0;
  84
  85 @@ -438,11 +414,6 @@ static int dummy_bulk_receive(struct vch
  86
  87         vchi_service_release(instance->handle);
  88
  89 -       if (ret != 0) {
  90 -               /* callback will not be clearing the mutex */
  91 -               mutex_unlock(&instance->bulk_mutex);
  92 -       }
  93 -
  94         return ret;
  95  }
  96
  97 @@ -497,18 +468,11 @@ buffer_from_host(struct vchiq_mmal_insta
  98
  99         pr_debug("instance:%p buffer:%p\n", instance->handle, buf);
 100
 101 -       /* bulk mutex stops other bulk operations while we
 102 -        * have a receive in progress
 103 -        */
 104 -       if (mutex_lock_interruptible(&instance->bulk_mutex))
 105 -               return -EINTR;
 106 -
 107         /* get context */
 108         if (!buf->msg_context) {
 109                 pr_err("%s: msg_context not allocated, buf %p\n", __func__,
 110                        buf);
 111 -               ret = -EINVAL;
 112 -               goto unlock;
 113 +               return -EINVAL;
 114         }
 115         msg_context = buf->msg_context;
 116
 117 @@ -562,9 +526,6 @@ buffer_from_host(struct vchiq_mmal_insta
 118
 119         vchi_service_release(instance->handle);
 120
 121 -unlock:
 122 -       mutex_unlock(&instance->bulk_mutex);
 123 -
 124         return ret;
 125  }
 126
 127 @@ -688,9 +649,6 @@ static void buffer_to_host_cb(struct vch
 128  static void bulk_receive_cb(struct vchiq_mmal_instance *instance,
 129                             struct mmal_msg_context *msg_context)
 130  {
 131 -       /* bulk receive operation complete */
 132 -       mutex_unlock(&msg_context->u.bulk.instance->bulk_mutex);
 133 -
 134         /* replace the buffer header */
 135         port_buffer_from_host(msg_context->u.bulk.instance,
 136                               msg_context->u.bulk.port);
 137 @@ -706,9 +664,6 @@ static void bulk_abort_cb(struct vchiq_m
 138  {
 139         pr_err("%s: bulk ABORTED msg_context:%p\n", __func__, msg_context);
 140
 141 -       /* bulk receive operation complete */
 142 -       mutex_unlock(&msg_context->u.bulk.instance->bulk_mutex);
 143 -
 144         /* replace the buffer header */
 145         port_buffer_from_host(msg_context->u.bulk.instance,
 146                               msg_context->u.bulk.port);
 147 @@ -2047,7 +2002,6 @@ int vchiq_mmal_init(struct vchiq_mmal_in
 148                 return -ENOMEM;
 149
 150         mutex_init(&instance->vchiq_mutex);
 151 -       mutex_init(&instance->bulk_mutex);
 152
 153         instance->bulk_scratch = vmalloc(PAGE_SIZE);
 154