From a9349315f65cd6a16e8fab1f6cf0fd40f379c4db Mon Sep 17 00:00:00 2001 From: Uri Shkolnik Date: Sun, 17 May 2009 05:59:37 -0300 Subject: V4L/DVB (11819): Siano: smscore - fix get_common_buffer bug get common buffers() should block operation until valid buffer is avaliable. Signed-off-by: Uri Shkolnik Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/siano/smscoreapi.c | 38 +++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-) (limited to 'drivers/media/dvb') diff --git a/drivers/media/dvb/siano/smscoreapi.c b/drivers/media/dvb/siano/smscoreapi.c index 040a3ff..9a5358c 100644 --- a/drivers/media/dvb/siano/smscoreapi.c +++ b/drivers/media/dvb/siano/smscoreapi.c @@ -30,6 +30,7 @@ #include #include +#include #include "smscoreapi.h" #include "sms-cards.h" @@ -352,6 +353,9 @@ int smscore_register_device(struct smsdevice_params_t *params, init_completion(&dev->resume_done); init_completion(&dev->ir_init_done); + /* Buffer management */ + init_waitqueue_head(&dev->buffer_mng_waitq); + /* alloc common buffer */ dev->common_buffer_size = params->buffer_size * params->num_buffers; dev->common_buffer = dma_alloc_coherent(NULL, dev->common_buffer_size, @@ -686,7 +690,9 @@ void smscore_unregister_device(struct smscore_device_t *coredev) * onresponse must no longer be called */ while (1) { - while ((cb = smscore_getbuffer(coredev))) { + while (!list_empty(&coredev->buffers)) { + cb = (struct smscore_buffer_t *) coredev->buffers.next; + list_del(&cb->entry); kfree(cb); num_buffers++; } @@ -707,8 +713,10 @@ void smscore_unregister_device(struct smscore_device_t *coredev) if (coredev->common_buffer) dma_free_coherent(NULL, coredev->common_buffer_size, - coredev->common_buffer, - coredev->common_buffer_phys); + coredev->common_buffer, coredev->common_buffer_phys); + + if (coredev->fw_buf != NULL) + kfree(coredev->fw_buf); list_del(&coredev->entry); kfree(coredev); @@ -1071,12 +1079,24 @@ struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev) struct smscore_buffer_t *cb = NULL; unsigned long flags; + DEFINE_WAIT(wait); + spin_lock_irqsave(&coredev->bufferslock, flags); - if (!list_empty(&coredev->buffers)) { - cb = (struct smscore_buffer_t *) coredev->buffers.next; - list_del(&cb->entry); - } + /* This function must return a valid buffer, since the buffer list is + * finite, we check that there is an available buffer, if not, we wait + * until such buffer become available. + */ + + prepare_to_wait(&coredev->buffer_mng_waitq, &wait, TASK_INTERRUPTIBLE); + + if (list_empty(&coredev->buffers)) + schedule(); + + finish_wait(&coredev->buffer_mng_waitq, &wait); + + cb = (struct smscore_buffer_t *) coredev->buffers.next; + list_del(&cb->entry); spin_unlock_irqrestore(&coredev->bufferslock, flags); @@ -1093,8 +1113,8 @@ EXPORT_SYMBOL_GPL(smscore_getbuffer); * */ void smscore_putbuffer(struct smscore_device_t *coredev, - struct smscore_buffer_t *cb) -{ + struct smscore_buffer_t *cb) { + wake_up_interruptible(&coredev->buffer_mng_waitq); list_add_locked(&cb->entry, &coredev->buffers, &coredev->bufferslock); } EXPORT_SYMBOL_GPL(smscore_putbuffer); -- cgit v1.1