[v4,01/10] media: videobuf2: Access vb2_queue bufs array through helper functions

Message ID 20230705121056.37017-2-benjamin.gaignard@collabora.com
State New
Headers
Series Add DELETE_BUF ioctl |

Commit Message

Benjamin Gaignard July 5, 2023, 12:10 p.m. UTC
  The first step before changing how vb2 buffers are stored into queue
is to avoid direct access to bufs arrays.

This patch adds 2 helpers functions to add and remove vb2 buffers
from a queue. With these 2 and vb2_get_buffer(), bufs field of
struct vb2_queue becomes like a private member of the structure.

After each call to vb2_get_buffer() we need to be sure that we get
a valid pointer so check the return value of all of them.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
---
 .../media/common/videobuf2/videobuf2-core.c   | 215 ++++++++++++++----
 .../media/common/videobuf2/videobuf2-v4l2.c   |  28 ++-
 drivers/media/platform/amphion/vpu_dbg.c      |  22 +-
 .../platform/mediatek/jpeg/mtk_jpeg_core.c    |   6 +-
 .../vcodec/vdec/vdec_vp9_req_lat_if.c         |   2 +-
 drivers/media/platform/st/sti/hva/hva-v4l2.c  |   4 +
 drivers/media/test-drivers/visl/visl-dec.c    |  28 ++-
 .../staging/media/atomisp/pci/atomisp_ioctl.c |   2 +-
 8 files changed, 240 insertions(+), 67 deletions(-)
  

Comments

Hans Verkuil Aug. 21, 2023, 2:31 p.m. UTC | #1
On 21/08/2023 16:24, Hans Verkuil wrote:
> Hi Benjamin,
> 
> On 05/07/2023 14:10, Benjamin Gaignard wrote:
>> The first step before changing how vb2 buffers are stored into queue
>> is to avoid direct access to bufs arrays.
>>
>> This patch adds 2 helpers functions to add and remove vb2 buffers
>> from a queue. With these 2 and vb2_get_buffer(), bufs field of
>> struct vb2_queue becomes like a private member of the structure.
>>
>> After each call to vb2_get_buffer() we need to be sure that we get
>> a valid pointer so check the return value of all of them.
>>
>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>> ---
>>  .../media/common/videobuf2/videobuf2-core.c   | 215 ++++++++++++++----
>>  .../media/common/videobuf2/videobuf2-v4l2.c   |  28 ++-
>>  drivers/media/platform/amphion/vpu_dbg.c      |  22 +-
>>  .../platform/mediatek/jpeg/mtk_jpeg_core.c    |   6 +-
>>  .../vcodec/vdec/vdec_vp9_req_lat_if.c         |   2 +-
>>  drivers/media/platform/st/sti/hva/hva-v4l2.c  |   4 +
>>  drivers/media/test-drivers/visl/visl-dec.c    |  28 ++-
>>  .../staging/media/atomisp/pci/atomisp_ioctl.c |   2 +-
>>  8 files changed, 240 insertions(+), 67 deletions(-)
>>
>> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
>> index cf6727d9c81f..42fd3984c2bc 100644
>> --- a/drivers/media/common/videobuf2/videobuf2-core.c
>> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
>> @@ -359,8 +359,16 @@ static void __setup_offsets(struct vb2_buffer *vb)
>>  	unsigned long off = 0;
>>  
>>  	if (vb->index) {
>> -		struct vb2_buffer *prev = q->bufs[vb->index - 1];
>> -		struct vb2_plane *p = &prev->planes[prev->num_planes - 1];
>> +		struct vb2_buffer *prev;
>> +		struct vb2_plane *p;
>> +
>> +		prev = vb2_get_buffer(q, vb->index - 1);
>> +		if (!prev) {
>> +			dprintk(q, 1, "can't find the requested buffer\n");
>> +			return;
>> +		}
>> +
>> +		p = &prev->planes[prev->num_planes - 1];
>>  
>>  		off = PAGE_ALIGN(p->m.offset + p->length);
> 
> This does not work. Before this patch there should be a patch that changes
> the way the offset is determined since it affects this functionality.
> 
> __setup_offsets() fills in the m.offset field for each plane in the buffer.
> In the current code it starts with 0 for the first buffer, adds the length
> for each plane to it, and for the next buffer it continues doing that. So
> the offset for a plane is the total length of all preceding buffers and planes.
> 
> In addition, bit 30 of the offset field is used to signal if it is a capture
> or output buffer in the v4l2-mem2mem framework (see the DST_QUEUE_OFF_BASE
> define).
> 
> In addition, the offset has to be page aligned, so the lower 12 bits are 0.
> That leaves only 32-1-12 = 19 bits for the offset.
> 
> Since we allow 8 planes per buffer, that means that we can't have more than
> 65536 buffers given a 32 bit offset.
> 
> I think the way m.offset is calculated should change drastically: it should
> instead be something like this:
> 
> m.offset = ((vb->index << 3) | plane) << PAGE_SHIFT;
> 
> and DST_QUEUE_OFF_BASE should use bit 31 instead of 30.
> 
> Parsing the offset would be much simpler as well, since you can just decode
> the index and plane numbers directly rather than using the cumbersome
> __find_plane_by_offset() function.
> 
> The currently mechanism will fail completely once you can delete buffers,
> and this proposal will simplify and improve the code, so I think it should
> be done first.

I could have saved myself some work if I read the other patches first.

I see that patch 3/10 addresses this. But for the v5, just move that patch
to the beginning of the series.

I would also suggest changing DST_QUEUE_OFF_BASE to use bit 31 to allow for
16 bits instead of 15 for the buffer index.

Regards,

	Hans

> 
> Regards,
> 
> 	Hans
> 
>>  	}
>> @@ -397,6 +405,37 @@ static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb)
>>  		vb->skip_cache_sync_on_finish = 1;
>>  }
>>  
>> +/**
>> + * vb2_queue_add_buffer() - add a buffer to a queue
>> + * @q:	pointer to &struct vb2_queue with videobuf2 queue.
>> + * @vb:	pointer to &struct vb2_buffer to be added to the queue.
>> + * @index: index where add vb2_buffer in the queue
>> + */
>> +static bool vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, int index)
>> +{
>> +	if (index < VB2_MAX_FRAME && !q->bufs[index]) {
>> +		q->bufs[index] = vb;
>> +		vb->index = index;
>> +		vb->vb2_queue = q;
>> +		return true;
>> +	}
>> +
>> +	return false;
>> +}
>> +
>> +/**
>> + * vb2_queue_remove_buffer() - remove a buffer from a queue
>> + * @q:	pointer to &struct vb2_queue with videobuf2 queue.
>> + * @vb:	pointer to &struct vb2_buffer to be removed from the queue.
>> + */
>> +static void vb2_queue_remove_buffer(struct vb2_queue *q, struct vb2_buffer *vb)
>> +{
>> +	if (vb->index < VB2_MAX_FRAME) {
>> +		q->bufs[vb->index] = NULL;
>> +		vb->vb2_queue = NULL;
>> +	}
>> +}
>> +
>>  /*
>>   * __vb2_queue_alloc() - allocate vb2 buffer structures and (for MMAP type)
>>   * video buffer memory for all buffers/planes on the queue and initializes the
>> @@ -425,9 +464,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
>>  		}
>>  
>>  		vb->state = VB2_BUF_STATE_DEQUEUED;
>> -		vb->vb2_queue = q;
>>  		vb->num_planes = num_planes;
>> -		vb->index = q->num_buffers + buffer;
>>  		vb->type = q->type;
>>  		vb->memory = memory;
>>  		init_buffer_cache_hints(q, vb);
>> @@ -437,7 +474,11 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
>>  		}
>>  		call_void_bufop(q, init_buffer, vb);
>>  
>> -		q->bufs[vb->index] = vb;
>> +		if (!vb2_queue_add_buffer(q, vb, q->num_buffers + buffer)) {
>> +			dprintk(q, 1, "failed adding buffer %d to queue\n", buffer);
>> +			kfree(vb);
>> +			break;
>> +		}
>>  
>>  		/* Allocate video buffer memory for the MMAP type */
>>  		if (memory == VB2_MEMORY_MMAP) {
>> @@ -445,7 +486,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
>>  			if (ret) {
>>  				dprintk(q, 1, "failed allocating memory for buffer %d\n",
>>  					buffer);
>> -				q->bufs[vb->index] = NULL;
>> +				vb2_queue_remove_buffer(q, vb);
>>  				kfree(vb);
>>  				break;
>>  			}
>> @@ -460,7 +501,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
>>  				dprintk(q, 1, "buffer %d %p initialization failed\n",
>>  					buffer, vb);
>>  				__vb2_buf_mem_free(vb);
>> -				q->bufs[vb->index] = NULL;
>> +				vb2_queue_remove_buffer(q, vb);
>>  				kfree(vb);
>>  				break;
>>  			}
>> @@ -483,7 +524,7 @@ static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
>>  
>>  	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
>>  	     ++buffer) {
>> -		vb = q->bufs[buffer];
>> +		vb = vb2_get_buffer(q, buffer);
>>  		if (!vb)
>>  			continue;
>>  
>> @@ -511,7 +552,7 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
>>  	/* Call driver-provided cleanup function for each buffer, if provided */
>>  	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
>>  	     ++buffer) {
>> -		struct vb2_buffer *vb = q->bufs[buffer];
>> +		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
>>  
>>  		if (vb && vb->planes[0].mem_priv)
>>  			call_void_vb_qop(vb, buf_cleanup, vb);
>> @@ -551,15 +592,20 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
>>  		q->cnt_unprepare_streaming = 0;
>>  	}
>>  	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
>> -		struct vb2_buffer *vb = q->bufs[buffer];
>> -		bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
>> -				  vb->cnt_mem_prepare != vb->cnt_mem_finish ||
>> -				  vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
>> -				  vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
>> -				  vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
>> -				  vb->cnt_buf_queue != vb->cnt_buf_done ||
>> -				  vb->cnt_buf_prepare != vb->cnt_buf_finish ||
>> -				  vb->cnt_buf_init != vb->cnt_buf_cleanup;
>> +		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
>> +		bool unbalanced;
>> +
>> +		if (!vb)
>> +			continue;
>> +
>> +		unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
>> +			     vb->cnt_mem_prepare != vb->cnt_mem_finish ||
>> +			     vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
>> +			     vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
>> +			     vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
>> +			     vb->cnt_buf_queue != vb->cnt_buf_done ||
>> +			     vb->cnt_buf_prepare != vb->cnt_buf_finish ||
>> +			     vb->cnt_buf_init != vb->cnt_buf_cleanup;
>>  
>>  		if (unbalanced || debug) {
>>  			pr_info("   counters for queue %p, buffer %d:%s\n",
>> @@ -591,8 +637,13 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
>>  	/* Free vb2 buffers */
>>  	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
>>  	     ++buffer) {
>> -		kfree(q->bufs[buffer]);
>> -		q->bufs[buffer] = NULL;
>> +		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
>> +
>> +		if (!vb)
>> +			continue;
>> +
>> +		vb2_queue_remove_buffer(q, vb);
>> +		kfree(vb);
>>  	}
>>  
>>  	q->num_buffers -= buffers;
>> @@ -628,7 +679,12 @@ static bool __buffers_in_use(struct vb2_queue *q)
>>  {
>>  	unsigned int buffer;
>>  	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
>> -		if (vb2_buffer_in_use(q, q->bufs[buffer]))
>> +		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
>> +
>> +		if (!vb)
>> +			continue;
>> +
>> +		if (vb2_buffer_in_use(q, vb))
>>  			return true;
>>  	}
>>  	return false;
>> @@ -636,7 +692,10 @@ static bool __buffers_in_use(struct vb2_queue *q)
>>  
>>  void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb)
>>  {
>> -	call_void_bufop(q, fill_user_buffer, q->bufs[index], pb);
>> +	struct vb2_buffer *vb = vb2_get_buffer(q, index);
>> +
>> +	if (vb)
>> +		call_void_bufop(q, fill_user_buffer, vb, pb);
>>  }
>>  EXPORT_SYMBOL_GPL(vb2_core_querybuf);
>>  
>> @@ -1547,7 +1606,13 @@ int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)
>>  	struct vb2_buffer *vb;
>>  	int ret;
>>  
>> -	vb = q->bufs[index];
>> +	vb = vb2_get_buffer(q, index);
>> +
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		return -EINVAL;
>> +	}
>> +
>>  	if (vb->state != VB2_BUF_STATE_DEQUEUED) {
>>  		dprintk(q, 1, "invalid buffer state %s\n",
>>  			vb2_state_name(vb->state));
>> @@ -1618,7 +1683,11 @@ static int vb2_start_streaming(struct vb2_queue *q)
>>  		 * correctly return them to vb2.
>>  		 */
>>  		for (i = 0; i < q->num_buffers; ++i) {
>> -			vb = q->bufs[i];
>> +			vb = vb2_get_buffer(q, i);
>> +
>> +			if (!vb)
>> +				continue;
>> +
>>  			if (vb->state == VB2_BUF_STATE_ACTIVE)
>>  				vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED);
>>  		}
>> @@ -1646,7 +1715,12 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
>>  		return -EIO;
>>  	}
>>  
>> -	vb = q->bufs[index];
>> +	vb = vb2_get_buffer(q, index);
>> +
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		return -EINVAL;
>> +	}
>>  
>>  	if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
>>  	    q->requires_requests) {
>> @@ -2022,12 +2096,18 @@ static void __vb2_queue_cancel(struct vb2_queue *q)
>>  	 * to vb2 in stop_streaming().
>>  	 */
>>  	if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
>> -		for (i = 0; i < q->num_buffers; ++i)
>> -			if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) {
>> +		for (i = 0; i < q->num_buffers; ++i) {
>> +			struct vb2_buffer *vb = vb2_get_buffer(q, i);
>> +
>> +			if (!vb)
>> +				continue;
>> +
>> +			if (vb->state == VB2_BUF_STATE_ACTIVE) {
>>  				pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n",
>> -					q->bufs[i]);
>> -				vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR);
>> +					vb);
>> +				vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
>>  			}
>> +		}
>>  		/* Must be zero now */
>>  		WARN_ON(atomic_read(&q->owned_by_drv_count));
>>  	}
>> @@ -2061,9 +2141,14 @@ static void __vb2_queue_cancel(struct vb2_queue *q)
>>  	 * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
>>  	 */
>>  	for (i = 0; i < q->num_buffers; ++i) {
>> -		struct vb2_buffer *vb = q->bufs[i];
>> -		struct media_request *req = vb->req_obj.req;
>> +		struct vb2_buffer *vb;
>> +		struct media_request *req;
>>  
>> +		vb = vb2_get_buffer(q, i);
>> +		if (!vb)
>> +			continue;
>> +
>> +		req = vb->req_obj.req;
>>  		/*
>>  		 * If a request is associated with this buffer, then
>>  		 * call buf_request_cancel() to give the driver to complete()
>> @@ -2215,7 +2300,10 @@ static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off,
>>  	 * return its buffer and plane numbers.
>>  	 */
>>  	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
>> -		vb = q->bufs[buffer];
>> +		vb = vb2_get_buffer(q, buffer);
>> +
>> +		if (!vb)
>> +			continue;
>>  
>>  		for (plane = 0; plane < vb->num_planes; ++plane) {
>>  			if (vb->planes[plane].m.offset == off) {
>> @@ -2262,7 +2350,12 @@ int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
>>  		return -EINVAL;
>>  	}
>>  
>> -	vb = q->bufs[index];
>> +	vb = vb2_get_buffer(q, index);
>> +
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		return -EINVAL;
>> +	}
>>  
>>  	if (plane >= vb->num_planes) {
>>  		dprintk(q, 1, "buffer plane out of range\n");
>> @@ -2339,7 +2432,13 @@ int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
>>  	if (ret)
>>  		goto unlock;
>>  
>> -	vb = q->bufs[buffer];
>> +	vb = vb2_get_buffer(q, buffer);
>> +
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		ret = -EINVAL;
>> +		goto unlock;
>> +	}
>>  
>>  	/*
>>  	 * MMAP requires page_aligned buffers.
>> @@ -2396,7 +2495,12 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
>>  	if (ret)
>>  		goto unlock;
>>  
>> -	vb = q->bufs[buffer];
>> +	vb = vb2_get_buffer(q, buffer);
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		ret = -EINVAL;
>> +		goto unlock;
>> +	}
>>  
>>  	vaddr = vb2_plane_vaddr(vb, plane);
>>  	mutex_unlock(&q->mmap_lock);
>> @@ -2625,6 +2729,7 @@ struct vb2_fileio_data {
>>  static int __vb2_init_fileio(struct vb2_queue *q, int read)
>>  {
>>  	struct vb2_fileio_data *fileio;
>> +	struct vb2_buffer *vb;
>>  	int i, ret;
>>  	unsigned int count = 0;
>>  
>> @@ -2679,7 +2784,13 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read)
>>  	 * Check if plane_count is correct
>>  	 * (multiplane buffers are not supported).
>>  	 */
>> -	if (q->bufs[0]->num_planes != 1) {
>> +	vb = vb2_get_buffer(q, 0);
>> +	if (!vb) {
>> +		ret = -EBUSY;
>> +		goto err_reqbufs;
>> +	}
>> +
>> +	if (vb->num_planes != 1) {
>>  		ret = -EBUSY;
>>  		goto err_reqbufs;
>>  	}
>> @@ -2688,12 +2799,17 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read)
>>  	 * Get kernel address of each buffer.
>>  	 */
>>  	for (i = 0; i < q->num_buffers; i++) {
>> -		fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0);
>> +		vb = vb2_get_buffer(q, i);
>> +
>> +		if (!vb)
>> +			continue;
>> +
>> +		fileio->bufs[i].vaddr = vb2_plane_vaddr(vb, 0);
>>  		if (fileio->bufs[i].vaddr == NULL) {
>>  			ret = -EINVAL;
>>  			goto err_reqbufs;
>>  		}
>> -		fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0);
>> +		fileio->bufs[i].size = vb2_plane_size(vb, 0);
>>  	}
>>  
>>  	/*
>> @@ -2821,15 +2937,18 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
>>  
>>  		fileio->cur_index = index;
>>  		buf = &fileio->bufs[index];
>> -		b = q->bufs[index];
>> +		b = vb2_get_buffer(q, index);
>> +
>> +		if (!b)
>> +			return -EINVAL;
>>  
>>  		/*
>>  		 * Get number of bytes filled by the driver
>>  		 */
>>  		buf->pos = 0;
>>  		buf->queued = 0;
>> -		buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0)
>> -				 : vb2_plane_size(q->bufs[index], 0);
>> +		buf->size = read ? vb2_get_plane_payload(b, 0)
>> +				 : vb2_plane_size(b, 0);
>>  		/* Compensate for data_offset on read in the multiplanar case. */
>>  		if (is_multiplanar && read &&
>>  				b->planes[0].data_offset < buf->size) {
>> @@ -2872,8 +2991,12 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
>>  	 * Queue next buffer if required.
>>  	 */
>>  	if (buf->pos == buf->size || (!read && fileio->write_immediately)) {
>> -		struct vb2_buffer *b = q->bufs[index];
>> +		struct vb2_buffer *b = vb2_get_buffer(q, index);
>>  
>> +		if (!b) {
>> +			dprintk(q, 1, "can't find the requested buffer\n");
>> +			return -EINVAL;
>> +		}
>>  		/*
>>  		 * Check if this is the last buffer to read.
>>  		 */
>> @@ -2899,7 +3022,7 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
>>  		 */
>>  		buf->pos = 0;
>>  		buf->queued = 1;
>> -		buf->size = vb2_plane_size(q->bufs[index], 0);
>> +		buf->size = vb2_plane_size(b, 0);
>>  		fileio->q_count += 1;
>>  		/*
>>  		 * If we are queuing up buffers for the first time, then
>> @@ -2970,7 +3093,9 @@ static int vb2_thread(void *data)
>>  		 * Call vb2_dqbuf to get buffer back.
>>  		 */
>>  		if (prequeue) {
>> -			vb = q->bufs[index++];
>> +			vb = vb2_get_buffer(q, index++);
>> +			if (!vb)
>> +				continue;
>>  			prequeue--;
>>  		} else {
>>  			call_void_qop(q, wait_finish, q);
>> @@ -2979,7 +3104,7 @@ static int vb2_thread(void *data)
>>  			call_void_qop(q, wait_prepare, q);
>>  			dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret);
>>  			if (!ret)
>> -				vb = q->bufs[index];
>> +				vb = vb2_get_buffer(q, index);
>>  		}
>>  		if (ret || threadio->stop)
>>  			break;
>> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
>> index c7a54d82a55e..724135d41f7f 100644
>> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
>> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
>> @@ -383,8 +383,7 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
>>  		return -EINVAL;
>>  	}
>>  
>> -	if (q->bufs[b->index] == NULL) {
>> -		/* Should never happen */
>> +	if (!vb2_get_buffer(q, b->index)) {
>>  		dprintk(q, 1, "%s: buffer is NULL\n", opname);
>>  		return -EINVAL;
>>  	}
>> @@ -394,7 +393,7 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
>>  		return -EINVAL;
>>  	}
>>  
>> -	vb = q->bufs[b->index];
>> +	vb = vb2_get_buffer(q, b->index);
>>  	vbuf = to_vb2_v4l2_buffer(vb);
>>  	ret = __verify_planes_array(vb, b);
>>  	if (ret)
>> @@ -628,11 +627,18 @@ static const struct vb2_buf_ops v4l2_buf_ops = {
>>  struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp)
>>  {
>>  	unsigned int i;
>> +	struct vb2_buffer *vb2;
>>  
>> -	for (i = 0; i < q->num_buffers; i++)
>> -		if (q->bufs[i]->copied_timestamp &&
>> -		    q->bufs[i]->timestamp == timestamp)
>> -			return vb2_get_buffer(q, i);
>> +	for (i = 0; i < q->num_buffers; i++) {
>> +		vb2 = vb2_get_buffer(q, i);
>> +
>> +		if (!vb2)
>> +			continue;
>> +
>> +		if (vb2->copied_timestamp &&
>> +		    vb2->timestamp == timestamp)
>> +			return vb2;
>> +	}
>>  	return NULL;
>>  }
>>  EXPORT_SYMBOL_GPL(vb2_find_buffer);
>> @@ -664,7 +670,13 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
>>  		dprintk(q, 1, "buffer index out of range\n");
>>  		return -EINVAL;
>>  	}
>> -	vb = q->bufs[b->index];
>> +	vb = vb2_get_buffer(q, b->index);
>> +
>> +	if (!vb) {
>> +		dprintk(q, 1, "can't find the requested buffer\n");
>> +		return -EINVAL;
>> +	}
>> +
>>  	ret = __verify_planes_array(vb, b);
>>  	if (!ret)
>>  		vb2_core_querybuf(q, b->index, b);
>> diff --git a/drivers/media/platform/amphion/vpu_dbg.c b/drivers/media/platform/amphion/vpu_dbg.c
>> index 44b830ae01d8..e2c371c2fde5 100644
>> --- a/drivers/media/platform/amphion/vpu_dbg.c
>> +++ b/drivers/media/platform/amphion/vpu_dbg.c
>> @@ -133,11 +133,18 @@ static int vpu_dbg_instance(struct seq_file *s, void *data)
>>  
>>  	vq = v4l2_m2m_get_src_vq(inst->fh.m2m_ctx);
>>  	for (i = 0; i < vq->num_buffers; i++) {
>> -		struct vb2_buffer *vb = vq->bufs[i];
>> -		struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>> +		struct vb2_buffer *vb;
>> +		struct vb2_v4l2_buffer *vbuf;
>> +
>> +		vb = vb2_get_buffer(vq, i);
>> +		if (!vb)
>> +			continue;
>>  
>>  		if (vb->state == VB2_BUF_STATE_DEQUEUED)
>>  			continue;
>> +
>> +		vbuf = to_vb2_v4l2_buffer(vb);
>> +
>>  		num = scnprintf(str, sizeof(str),
>>  				"output [%2d] state = %10s, %8s\n",
>>  				i, vb2_stat_name[vb->state],
>> @@ -148,11 +155,18 @@ static int vpu_dbg_instance(struct seq_file *s, void *data)
>>  
>>  	vq = v4l2_m2m_get_dst_vq(inst->fh.m2m_ctx);
>>  	for (i = 0; i < vq->num_buffers; i++) {
>> -		struct vb2_buffer *vb = vq->bufs[i];
>> -		struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
>> +		struct vb2_buffer *vb;
>> +		struct vb2_v4l2_buffer *vbuf;
>> +
>> +		vb = vb2_get_buffer(vq, i);
>> +		if (!vb)
>> +			continue;
>>  
>>  		if (vb->state == VB2_BUF_STATE_DEQUEUED)
>>  			continue;
>> +
>> +		vbuf = to_vb2_v4l2_buffer(vb);
>> +
>>  		num = scnprintf(str, sizeof(str),
>>  				"capture[%2d] state = %10s, %8s\n",
>>  				i, vb2_stat_name[vb->state],
>> diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
>> index 0051f372a66c..ea37069ba355 100644
>> --- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
>> +++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
>> @@ -603,7 +603,11 @@ static int mtk_jpeg_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
>>  		return -EINVAL;
>>  	}
>>  
>> -	vb = vq->bufs[buf->index];
>> +	vb = vb2_get_buffer(vq, buf->index);
>> +	if (!vb) {
>> +		dev_err(ctx->jpeg->dev, "buffer not found\n");
>> +		return -EINVAL;
>> +	}
>>  	jpeg_src_buf = mtk_jpeg_vb2_to_srcbuf(vb);
>>  	jpeg_src_buf->bs_size = buf->m.planes[0].bytesused;
>>  
>> diff --git a/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c b/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
>> index cf16cf2807f0..6532a69f1fa8 100644
>> --- a/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
>> +++ b/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
>> @@ -1701,7 +1701,7 @@ static int vdec_vp9_slice_setup_core_buffer(struct vdec_vp9_slice_instance *inst
>>  
>>  	/* update internal buffer's width/height */
>>  	for (i = 0; i < vq->num_buffers; i++) {
>> -		if (vb == vq->bufs[i]) {
>> +		if (vb == vb2_get_buffer(vq, i)) {
>>  			instance->dpb[i].width = w;
>>  			instance->dpb[i].height = h;
>>  			break;
>> diff --git a/drivers/media/platform/st/sti/hva/hva-v4l2.c b/drivers/media/platform/st/sti/hva/hva-v4l2.c
>> index 3a848ca32a0e..326be09bdb55 100644
>> --- a/drivers/media/platform/st/sti/hva/hva-v4l2.c
>> +++ b/drivers/media/platform/st/sti/hva/hva-v4l2.c
>> @@ -577,6 +577,10 @@ static int hva_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
>>  		}
>>  
>>  		vb2_buf = vb2_get_buffer(vq, buf->index);
>> +		if (!vb2_buf) {
>> +			dev_dbg(dev, "%s buffer index %d not found\n", ctx->name, buf->index);
>> +			return -EINVAL;
>> +		}
>>  		stream = to_hva_stream(to_vb2_v4l2_buffer(vb2_buf));
>>  		stream->bytesused = buf->bytesused;
>>  	}
>> diff --git a/drivers/media/test-drivers/visl/visl-dec.c b/drivers/media/test-drivers/visl/visl-dec.c
>> index 318d675e5668..ba20ea998d19 100644
>> --- a/drivers/media/test-drivers/visl/visl-dec.c
>> +++ b/drivers/media/test-drivers/visl/visl-dec.c
>> @@ -290,13 +290,20 @@ static void visl_tpg_fill(struct visl_ctx *ctx, struct visl_run *run)
>>  	for (i = 0; i < out_q->num_buffers; i++) {
>>  		char entry[] = "index: %u, state: %s, request_fd: %d, ";
>>  		u32 old_len = len;
>> -		char *q_status = visl_get_vb2_state(out_q->bufs[i]->state);
>> +		struct vb2_buffer *vb2;
>> +		char *q_status;
>> +
>> +		vb2 = vb2_get_buffer(out_q, i);
>> +		if (!vb2)
>> +			continue;
>> +
>> +		q_status = visl_get_vb2_state(vb2->state);
>>  
>>  		len += scnprintf(&buf[len], TPG_STR_BUF_SZ - len,
>>  				 entry, i, q_status,
>> -				 to_vb2_v4l2_buffer(out_q->bufs[i])->request_fd);
>> +				 to_vb2_v4l2_buffer(vb2)->request_fd);
>>  
>> -		len += visl_fill_bytesused(to_vb2_v4l2_buffer(out_q->bufs[i]),
>> +		len += visl_fill_bytesused(to_vb2_v4l2_buffer(vb2),
>>  					   &buf[len],
>>  					   TPG_STR_BUF_SZ - len);
>>  
>> @@ -342,13 +349,20 @@ static void visl_tpg_fill(struct visl_ctx *ctx, struct visl_run *run)
>>  	len = 0;
>>  	for (i = 0; i < cap_q->num_buffers; i++) {
>>  		u32 old_len = len;
>> -		char *q_status = visl_get_vb2_state(cap_q->bufs[i]->state);
>> +		struct vb2_buffer *vb2;
>> +		char *q_status;
>> +
>> +		vb2 = vb2_get_buffer(cap_q, i);
>> +		if (!vb2)
>> +			continue;
>> +
>> +		q_status = visl_get_vb2_state(vb2->state);
>>  
>>  		len += scnprintf(&buf[len], TPG_STR_BUF_SZ - len,
>>  				 "index: %u, status: %s, timestamp: %llu, is_held: %d",
>> -				 cap_q->bufs[i]->index, q_status,
>> -				 cap_q->bufs[i]->timestamp,
>> -				 to_vb2_v4l2_buffer(cap_q->bufs[i])->is_held);
>> +				 vb2->index, q_status,
>> +				 vb2->timestamp,
>> +				 to_vb2_v4l2_buffer(vb2)->is_held);
>>  
>>  		tpg_gen_text(&ctx->tpg, basep, line++ * line_height, 16, &buf[old_len]);
>>  		frame_dprintk(ctx->dev, run->dst->sequence, "%s", &buf[old_len]);
>> diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
>> index 384f31fc66c5..8df301ab41ad 100644
>> --- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
>> +++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
>> @@ -1077,7 +1077,7 @@ static int atomisp_dqbuf_wrapper(struct file *file, void *fh, struct v4l2_buffer
>>  	if (ret)
>>  		return ret;
>>  
>> -	vb = pipe->vb_queue.bufs[buf->index];
>> +	vb = vb2_get_buffer(&pipe->vb_queue, buf->index);
>>  	frame = vb_to_frame(vb);
>>  
>>  	buf->reserved = asd->frame_status[buf->index];
>
  

Patch

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index cf6727d9c81f..42fd3984c2bc 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -359,8 +359,16 @@  static void __setup_offsets(struct vb2_buffer *vb)
 	unsigned long off = 0;
 
 	if (vb->index) {
-		struct vb2_buffer *prev = q->bufs[vb->index - 1];
-		struct vb2_plane *p = &prev->planes[prev->num_planes - 1];
+		struct vb2_buffer *prev;
+		struct vb2_plane *p;
+
+		prev = vb2_get_buffer(q, vb->index - 1);
+		if (!prev) {
+			dprintk(q, 1, "can't find the requested buffer\n");
+			return;
+		}
+
+		p = &prev->planes[prev->num_planes - 1];
 
 		off = PAGE_ALIGN(p->m.offset + p->length);
 	}
@@ -397,6 +405,37 @@  static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb)
 		vb->skip_cache_sync_on_finish = 1;
 }
 
+/**
+ * vb2_queue_add_buffer() - add a buffer to a queue
+ * @q:	pointer to &struct vb2_queue with videobuf2 queue.
+ * @vb:	pointer to &struct vb2_buffer to be added to the queue.
+ * @index: index where add vb2_buffer in the queue
+ */
+static bool vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, int index)
+{
+	if (index < VB2_MAX_FRAME && !q->bufs[index]) {
+		q->bufs[index] = vb;
+		vb->index = index;
+		vb->vb2_queue = q;
+		return true;
+	}
+
+	return false;
+}
+
+/**
+ * vb2_queue_remove_buffer() - remove a buffer from a queue
+ * @q:	pointer to &struct vb2_queue with videobuf2 queue.
+ * @vb:	pointer to &struct vb2_buffer to be removed from the queue.
+ */
+static void vb2_queue_remove_buffer(struct vb2_queue *q, struct vb2_buffer *vb)
+{
+	if (vb->index < VB2_MAX_FRAME) {
+		q->bufs[vb->index] = NULL;
+		vb->vb2_queue = NULL;
+	}
+}
+
 /*
  * __vb2_queue_alloc() - allocate vb2 buffer structures and (for MMAP type)
  * video buffer memory for all buffers/planes on the queue and initializes the
@@ -425,9 +464,7 @@  static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
 		}
 
 		vb->state = VB2_BUF_STATE_DEQUEUED;
-		vb->vb2_queue = q;
 		vb->num_planes = num_planes;
-		vb->index = q->num_buffers + buffer;
 		vb->type = q->type;
 		vb->memory = memory;
 		init_buffer_cache_hints(q, vb);
@@ -437,7 +474,11 @@  static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
 		}
 		call_void_bufop(q, init_buffer, vb);
 
-		q->bufs[vb->index] = vb;
+		if (!vb2_queue_add_buffer(q, vb, q->num_buffers + buffer)) {
+			dprintk(q, 1, "failed adding buffer %d to queue\n", buffer);
+			kfree(vb);
+			break;
+		}
 
 		/* Allocate video buffer memory for the MMAP type */
 		if (memory == VB2_MEMORY_MMAP) {
@@ -445,7 +486,7 @@  static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
 			if (ret) {
 				dprintk(q, 1, "failed allocating memory for buffer %d\n",
 					buffer);
-				q->bufs[vb->index] = NULL;
+				vb2_queue_remove_buffer(q, vb);
 				kfree(vb);
 				break;
 			}
@@ -460,7 +501,7 @@  static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
 				dprintk(q, 1, "buffer %d %p initialization failed\n",
 					buffer, vb);
 				__vb2_buf_mem_free(vb);
-				q->bufs[vb->index] = NULL;
+				vb2_queue_remove_buffer(q, vb);
 				kfree(vb);
 				break;
 			}
@@ -483,7 +524,7 @@  static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
 
 	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 	     ++buffer) {
-		vb = q->bufs[buffer];
+		vb = vb2_get_buffer(q, buffer);
 		if (!vb)
 			continue;
 
@@ -511,7 +552,7 @@  static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
 	/* Call driver-provided cleanup function for each buffer, if provided */
 	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 	     ++buffer) {
-		struct vb2_buffer *vb = q->bufs[buffer];
+		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
 
 		if (vb && vb->planes[0].mem_priv)
 			call_void_vb_qop(vb, buf_cleanup, vb);
@@ -551,15 +592,20 @@  static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
 		q->cnt_unprepare_streaming = 0;
 	}
 	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
-		struct vb2_buffer *vb = q->bufs[buffer];
-		bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
-				  vb->cnt_mem_prepare != vb->cnt_mem_finish ||
-				  vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
-				  vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
-				  vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
-				  vb->cnt_buf_queue != vb->cnt_buf_done ||
-				  vb->cnt_buf_prepare != vb->cnt_buf_finish ||
-				  vb->cnt_buf_init != vb->cnt_buf_cleanup;
+		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+		bool unbalanced;
+
+		if (!vb)
+			continue;
+
+		unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
+			     vb->cnt_mem_prepare != vb->cnt_mem_finish ||
+			     vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
+			     vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
+			     vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
+			     vb->cnt_buf_queue != vb->cnt_buf_done ||
+			     vb->cnt_buf_prepare != vb->cnt_buf_finish ||
+			     vb->cnt_buf_init != vb->cnt_buf_cleanup;
 
 		if (unbalanced || debug) {
 			pr_info("   counters for queue %p, buffer %d:%s\n",
@@ -591,8 +637,13 @@  static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
 	/* Free vb2 buffers */
 	for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 	     ++buffer) {
-		kfree(q->bufs[buffer]);
-		q->bufs[buffer] = NULL;
+		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+
+		if (!vb)
+			continue;
+
+		vb2_queue_remove_buffer(q, vb);
+		kfree(vb);
 	}
 
 	q->num_buffers -= buffers;
@@ -628,7 +679,12 @@  static bool __buffers_in_use(struct vb2_queue *q)
 {
 	unsigned int buffer;
 	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
-		if (vb2_buffer_in_use(q, q->bufs[buffer]))
+		struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+
+		if (!vb)
+			continue;
+
+		if (vb2_buffer_in_use(q, vb))
 			return true;
 	}
 	return false;
@@ -636,7 +692,10 @@  static bool __buffers_in_use(struct vb2_queue *q)
 
 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb)
 {
-	call_void_bufop(q, fill_user_buffer, q->bufs[index], pb);
+	struct vb2_buffer *vb = vb2_get_buffer(q, index);
+
+	if (vb)
+		call_void_bufop(q, fill_user_buffer, vb, pb);
 }
 EXPORT_SYMBOL_GPL(vb2_core_querybuf);
 
@@ -1547,7 +1606,13 @@  int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)
 	struct vb2_buffer *vb;
 	int ret;
 
-	vb = q->bufs[index];
+	vb = vb2_get_buffer(q, index);
+
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		return -EINVAL;
+	}
+
 	if (vb->state != VB2_BUF_STATE_DEQUEUED) {
 		dprintk(q, 1, "invalid buffer state %s\n",
 			vb2_state_name(vb->state));
@@ -1618,7 +1683,11 @@  static int vb2_start_streaming(struct vb2_queue *q)
 		 * correctly return them to vb2.
 		 */
 		for (i = 0; i < q->num_buffers; ++i) {
-			vb = q->bufs[i];
+			vb = vb2_get_buffer(q, i);
+
+			if (!vb)
+				continue;
+
 			if (vb->state == VB2_BUF_STATE_ACTIVE)
 				vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED);
 		}
@@ -1646,7 +1715,12 @@  int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
 		return -EIO;
 	}
 
-	vb = q->bufs[index];
+	vb = vb2_get_buffer(q, index);
+
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		return -EINVAL;
+	}
 
 	if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
 	    q->requires_requests) {
@@ -2022,12 +2096,18 @@  static void __vb2_queue_cancel(struct vb2_queue *q)
 	 * to vb2 in stop_streaming().
 	 */
 	if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
-		for (i = 0; i < q->num_buffers; ++i)
-			if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) {
+		for (i = 0; i < q->num_buffers; ++i) {
+			struct vb2_buffer *vb = vb2_get_buffer(q, i);
+
+			if (!vb)
+				continue;
+
+			if (vb->state == VB2_BUF_STATE_ACTIVE) {
 				pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n",
-					q->bufs[i]);
-				vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR);
+					vb);
+				vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
 			}
+		}
 		/* Must be zero now */
 		WARN_ON(atomic_read(&q->owned_by_drv_count));
 	}
@@ -2061,9 +2141,14 @@  static void __vb2_queue_cancel(struct vb2_queue *q)
 	 * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
 	 */
 	for (i = 0; i < q->num_buffers; ++i) {
-		struct vb2_buffer *vb = q->bufs[i];
-		struct media_request *req = vb->req_obj.req;
+		struct vb2_buffer *vb;
+		struct media_request *req;
 
+		vb = vb2_get_buffer(q, i);
+		if (!vb)
+			continue;
+
+		req = vb->req_obj.req;
 		/*
 		 * If a request is associated with this buffer, then
 		 * call buf_request_cancel() to give the driver to complete()
@@ -2215,7 +2300,10 @@  static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off,
 	 * return its buffer and plane numbers.
 	 */
 	for (buffer = 0; buffer < q->num_buffers; ++buffer) {
-		vb = q->bufs[buffer];
+		vb = vb2_get_buffer(q, buffer);
+
+		if (!vb)
+			continue;
 
 		for (plane = 0; plane < vb->num_planes; ++plane) {
 			if (vb->planes[plane].m.offset == off) {
@@ -2262,7 +2350,12 @@  int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
 		return -EINVAL;
 	}
 
-	vb = q->bufs[index];
+	vb = vb2_get_buffer(q, index);
+
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		return -EINVAL;
+	}
 
 	if (plane >= vb->num_planes) {
 		dprintk(q, 1, "buffer plane out of range\n");
@@ -2339,7 +2432,13 @@  int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
 	if (ret)
 		goto unlock;
 
-	vb = q->bufs[buffer];
+	vb = vb2_get_buffer(q, buffer);
+
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		ret = -EINVAL;
+		goto unlock;
+	}
 
 	/*
 	 * MMAP requires page_aligned buffers.
@@ -2396,7 +2495,12 @@  unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
 	if (ret)
 		goto unlock;
 
-	vb = q->bufs[buffer];
+	vb = vb2_get_buffer(q, buffer);
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		ret = -EINVAL;
+		goto unlock;
+	}
 
 	vaddr = vb2_plane_vaddr(vb, plane);
 	mutex_unlock(&q->mmap_lock);
@@ -2625,6 +2729,7 @@  struct vb2_fileio_data {
 static int __vb2_init_fileio(struct vb2_queue *q, int read)
 {
 	struct vb2_fileio_data *fileio;
+	struct vb2_buffer *vb;
 	int i, ret;
 	unsigned int count = 0;
 
@@ -2679,7 +2784,13 @@  static int __vb2_init_fileio(struct vb2_queue *q, int read)
 	 * Check if plane_count is correct
 	 * (multiplane buffers are not supported).
 	 */
-	if (q->bufs[0]->num_planes != 1) {
+	vb = vb2_get_buffer(q, 0);
+	if (!vb) {
+		ret = -EBUSY;
+		goto err_reqbufs;
+	}
+
+	if (vb->num_planes != 1) {
 		ret = -EBUSY;
 		goto err_reqbufs;
 	}
@@ -2688,12 +2799,17 @@  static int __vb2_init_fileio(struct vb2_queue *q, int read)
 	 * Get kernel address of each buffer.
 	 */
 	for (i = 0; i < q->num_buffers; i++) {
-		fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0);
+		vb = vb2_get_buffer(q, i);
+
+		if (!vb)
+			continue;
+
+		fileio->bufs[i].vaddr = vb2_plane_vaddr(vb, 0);
 		if (fileio->bufs[i].vaddr == NULL) {
 			ret = -EINVAL;
 			goto err_reqbufs;
 		}
-		fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0);
+		fileio->bufs[i].size = vb2_plane_size(vb, 0);
 	}
 
 	/*
@@ -2821,15 +2937,18 @@  static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
 
 		fileio->cur_index = index;
 		buf = &fileio->bufs[index];
-		b = q->bufs[index];
+		b = vb2_get_buffer(q, index);
+
+		if (!b)
+			return -EINVAL;
 
 		/*
 		 * Get number of bytes filled by the driver
 		 */
 		buf->pos = 0;
 		buf->queued = 0;
-		buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0)
-				 : vb2_plane_size(q->bufs[index], 0);
+		buf->size = read ? vb2_get_plane_payload(b, 0)
+				 : vb2_plane_size(b, 0);
 		/* Compensate for data_offset on read in the multiplanar case. */
 		if (is_multiplanar && read &&
 				b->planes[0].data_offset < buf->size) {
@@ -2872,8 +2991,12 @@  static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
 	 * Queue next buffer if required.
 	 */
 	if (buf->pos == buf->size || (!read && fileio->write_immediately)) {
-		struct vb2_buffer *b = q->bufs[index];
+		struct vb2_buffer *b = vb2_get_buffer(q, index);
 
+		if (!b) {
+			dprintk(q, 1, "can't find the requested buffer\n");
+			return -EINVAL;
+		}
 		/*
 		 * Check if this is the last buffer to read.
 		 */
@@ -2899,7 +3022,7 @@  static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
 		 */
 		buf->pos = 0;
 		buf->queued = 1;
-		buf->size = vb2_plane_size(q->bufs[index], 0);
+		buf->size = vb2_plane_size(b, 0);
 		fileio->q_count += 1;
 		/*
 		 * If we are queuing up buffers for the first time, then
@@ -2970,7 +3093,9 @@  static int vb2_thread(void *data)
 		 * Call vb2_dqbuf to get buffer back.
 		 */
 		if (prequeue) {
-			vb = q->bufs[index++];
+			vb = vb2_get_buffer(q, index++);
+			if (!vb)
+				continue;
 			prequeue--;
 		} else {
 			call_void_qop(q, wait_finish, q);
@@ -2979,7 +3104,7 @@  static int vb2_thread(void *data)
 			call_void_qop(q, wait_prepare, q);
 			dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret);
 			if (!ret)
-				vb = q->bufs[index];
+				vb = vb2_get_buffer(q, index);
 		}
 		if (ret || threadio->stop)
 			break;
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index c7a54d82a55e..724135d41f7f 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -383,8 +383,7 @@  static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
 		return -EINVAL;
 	}
 
-	if (q->bufs[b->index] == NULL) {
-		/* Should never happen */
+	if (!vb2_get_buffer(q, b->index)) {
 		dprintk(q, 1, "%s: buffer is NULL\n", opname);
 		return -EINVAL;
 	}
@@ -394,7 +393,7 @@  static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
 		return -EINVAL;
 	}
 
-	vb = q->bufs[b->index];
+	vb = vb2_get_buffer(q, b->index);
 	vbuf = to_vb2_v4l2_buffer(vb);
 	ret = __verify_planes_array(vb, b);
 	if (ret)
@@ -628,11 +627,18 @@  static const struct vb2_buf_ops v4l2_buf_ops = {
 struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp)
 {
 	unsigned int i;
+	struct vb2_buffer *vb2;
 
-	for (i = 0; i < q->num_buffers; i++)
-		if (q->bufs[i]->copied_timestamp &&
-		    q->bufs[i]->timestamp == timestamp)
-			return vb2_get_buffer(q, i);
+	for (i = 0; i < q->num_buffers; i++) {
+		vb2 = vb2_get_buffer(q, i);
+
+		if (!vb2)
+			continue;
+
+		if (vb2->copied_timestamp &&
+		    vb2->timestamp == timestamp)
+			return vb2;
+	}
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(vb2_find_buffer);
@@ -664,7 +670,13 @@  int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
 		dprintk(q, 1, "buffer index out of range\n");
 		return -EINVAL;
 	}
-	vb = q->bufs[b->index];
+	vb = vb2_get_buffer(q, b->index);
+
+	if (!vb) {
+		dprintk(q, 1, "can't find the requested buffer\n");
+		return -EINVAL;
+	}
+
 	ret = __verify_planes_array(vb, b);
 	if (!ret)
 		vb2_core_querybuf(q, b->index, b);
diff --git a/drivers/media/platform/amphion/vpu_dbg.c b/drivers/media/platform/amphion/vpu_dbg.c
index 44b830ae01d8..e2c371c2fde5 100644
--- a/drivers/media/platform/amphion/vpu_dbg.c
+++ b/drivers/media/platform/amphion/vpu_dbg.c
@@ -133,11 +133,18 @@  static int vpu_dbg_instance(struct seq_file *s, void *data)
 
 	vq = v4l2_m2m_get_src_vq(inst->fh.m2m_ctx);
 	for (i = 0; i < vq->num_buffers; i++) {
-		struct vb2_buffer *vb = vq->bufs[i];
-		struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+		struct vb2_buffer *vb;
+		struct vb2_v4l2_buffer *vbuf;
+
+		vb = vb2_get_buffer(vq, i);
+		if (!vb)
+			continue;
 
 		if (vb->state == VB2_BUF_STATE_DEQUEUED)
 			continue;
+
+		vbuf = to_vb2_v4l2_buffer(vb);
+
 		num = scnprintf(str, sizeof(str),
 				"output [%2d] state = %10s, %8s\n",
 				i, vb2_stat_name[vb->state],
@@ -148,11 +155,18 @@  static int vpu_dbg_instance(struct seq_file *s, void *data)
 
 	vq = v4l2_m2m_get_dst_vq(inst->fh.m2m_ctx);
 	for (i = 0; i < vq->num_buffers; i++) {
-		struct vb2_buffer *vb = vq->bufs[i];
-		struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+		struct vb2_buffer *vb;
+		struct vb2_v4l2_buffer *vbuf;
+
+		vb = vb2_get_buffer(vq, i);
+		if (!vb)
+			continue;
 
 		if (vb->state == VB2_BUF_STATE_DEQUEUED)
 			continue;
+
+		vbuf = to_vb2_v4l2_buffer(vb);
+
 		num = scnprintf(str, sizeof(str),
 				"capture[%2d] state = %10s, %8s\n",
 				i, vb2_stat_name[vb->state],
diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 0051f372a66c..ea37069ba355 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -603,7 +603,11 @@  static int mtk_jpeg_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
 		return -EINVAL;
 	}
 
-	vb = vq->bufs[buf->index];
+	vb = vb2_get_buffer(vq, buf->index);
+	if (!vb) {
+		dev_err(ctx->jpeg->dev, "buffer not found\n");
+		return -EINVAL;
+	}
 	jpeg_src_buf = mtk_jpeg_vb2_to_srcbuf(vb);
 	jpeg_src_buf->bs_size = buf->m.planes[0].bytesused;
 
diff --git a/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c b/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
index cf16cf2807f0..6532a69f1fa8 100644
--- a/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
+++ b/drivers/media/platform/mediatek/vcodec/vdec/vdec_vp9_req_lat_if.c
@@ -1701,7 +1701,7 @@  static int vdec_vp9_slice_setup_core_buffer(struct vdec_vp9_slice_instance *inst
 
 	/* update internal buffer's width/height */
 	for (i = 0; i < vq->num_buffers; i++) {
-		if (vb == vq->bufs[i]) {
+		if (vb == vb2_get_buffer(vq, i)) {
 			instance->dpb[i].width = w;
 			instance->dpb[i].height = h;
 			break;
diff --git a/drivers/media/platform/st/sti/hva/hva-v4l2.c b/drivers/media/platform/st/sti/hva/hva-v4l2.c
index 3a848ca32a0e..326be09bdb55 100644
--- a/drivers/media/platform/st/sti/hva/hva-v4l2.c
+++ b/drivers/media/platform/st/sti/hva/hva-v4l2.c
@@ -577,6 +577,10 @@  static int hva_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
 		}
 
 		vb2_buf = vb2_get_buffer(vq, buf->index);
+		if (!vb2_buf) {
+			dev_dbg(dev, "%s buffer index %d not found\n", ctx->name, buf->index);
+			return -EINVAL;
+		}
 		stream = to_hva_stream(to_vb2_v4l2_buffer(vb2_buf));
 		stream->bytesused = buf->bytesused;
 	}
diff --git a/drivers/media/test-drivers/visl/visl-dec.c b/drivers/media/test-drivers/visl/visl-dec.c
index 318d675e5668..ba20ea998d19 100644
--- a/drivers/media/test-drivers/visl/visl-dec.c
+++ b/drivers/media/test-drivers/visl/visl-dec.c
@@ -290,13 +290,20 @@  static void visl_tpg_fill(struct visl_ctx *ctx, struct visl_run *run)
 	for (i = 0; i < out_q->num_buffers; i++) {
 		char entry[] = "index: %u, state: %s, request_fd: %d, ";
 		u32 old_len = len;
-		char *q_status = visl_get_vb2_state(out_q->bufs[i]->state);
+		struct vb2_buffer *vb2;
+		char *q_status;
+
+		vb2 = vb2_get_buffer(out_q, i);
+		if (!vb2)
+			continue;
+
+		q_status = visl_get_vb2_state(vb2->state);
 
 		len += scnprintf(&buf[len], TPG_STR_BUF_SZ - len,
 				 entry, i, q_status,
-				 to_vb2_v4l2_buffer(out_q->bufs[i])->request_fd);
+				 to_vb2_v4l2_buffer(vb2)->request_fd);
 
-		len += visl_fill_bytesused(to_vb2_v4l2_buffer(out_q->bufs[i]),
+		len += visl_fill_bytesused(to_vb2_v4l2_buffer(vb2),
 					   &buf[len],
 					   TPG_STR_BUF_SZ - len);
 
@@ -342,13 +349,20 @@  static void visl_tpg_fill(struct visl_ctx *ctx, struct visl_run *run)
 	len = 0;
 	for (i = 0; i < cap_q->num_buffers; i++) {
 		u32 old_len = len;
-		char *q_status = visl_get_vb2_state(cap_q->bufs[i]->state);
+		struct vb2_buffer *vb2;
+		char *q_status;
+
+		vb2 = vb2_get_buffer(cap_q, i);
+		if (!vb2)
+			continue;
+
+		q_status = visl_get_vb2_state(vb2->state);
 
 		len += scnprintf(&buf[len], TPG_STR_BUF_SZ - len,
 				 "index: %u, status: %s, timestamp: %llu, is_held: %d",
-				 cap_q->bufs[i]->index, q_status,
-				 cap_q->bufs[i]->timestamp,
-				 to_vb2_v4l2_buffer(cap_q->bufs[i])->is_held);
+				 vb2->index, q_status,
+				 vb2->timestamp,
+				 to_vb2_v4l2_buffer(vb2)->is_held);
 
 		tpg_gen_text(&ctx->tpg, basep, line++ * line_height, 16, &buf[old_len]);
 		frame_dprintk(ctx->dev, run->dst->sequence, "%s", &buf[old_len]);
diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
index 384f31fc66c5..8df301ab41ad 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
@@ -1077,7 +1077,7 @@  static int atomisp_dqbuf_wrapper(struct file *file, void *fh, struct v4l2_buffer
 	if (ret)
 		return ret;
 
-	vb = pipe->vb_queue.bufs[buf->index];
+	vb = vb2_get_buffer(&pipe->vb_queue, buf->index);
 	frame = vb_to_frame(vb);
 
 	buf->reserved = asd->frame_status[buf->index];