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-rw-r--r--drivers/media/video/videobuf2-core.c294
-rw-r--r--include/media/videobuf2-core.h35
2 files changed, 270 insertions, 59 deletions
diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c
index f04f27d68cec..9005dc9991ab 100644
--- a/drivers/media/video/videobuf2-core.c
+++ b/drivers/media/video/videobuf2-core.c
@@ -38,7 +38,8 @@ module_param(debug, int, 0644);
(((q)->ops->op) ? ((q)->ops->op(args)) : 0)
#define V4L2_BUFFER_STATE_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \
- V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR)
+ V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \
+ V4L2_BUF_FLAG_PREPARED)
/**
* __vb2_buf_mem_alloc() - allocate video memory for the given buffer
@@ -109,13 +110,22 @@ static void __vb2_buf_userptr_put(struct vb2_buffer *vb)
* __setup_offsets() - setup unique offsets ("cookies") for every plane in
* every buffer on the queue
*/
-static void __setup_offsets(struct vb2_queue *q)
+static void __setup_offsets(struct vb2_queue *q, unsigned int n)
{
unsigned int buffer, plane;
struct vb2_buffer *vb;
- unsigned long off = 0;
+ unsigned long off;
- for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ if (q->num_buffers) {
+ struct v4l2_plane *p;
+ vb = q->bufs[q->num_buffers - 1];
+ p = &vb->v4l2_planes[vb->num_planes - 1];
+ off = PAGE_ALIGN(p->m.mem_offset + p->length);
+ } else {
+ off = 0;
+ }
+
+ for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) {
vb = q->bufs[buffer];
if (!vb)
continue;
@@ -161,7 +171,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
vb->state = VB2_BUF_STATE_DEQUEUED;
vb->vb2_queue = q;
vb->num_planes = num_planes;
- vb->v4l2_buf.index = buffer;
+ vb->v4l2_buf.index = q->num_buffers + buffer;
vb->v4l2_buf.type = q->type;
vb->v4l2_buf.memory = memory;
@@ -189,15 +199,13 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
}
}
- q->bufs[buffer] = vb;
+ q->bufs[q->num_buffers + buffer] = vb;
}
- q->num_buffers = buffer;
-
- __setup_offsets(q);
+ __setup_offsets(q, buffer);
dprintk(1, "Allocated %d buffers, %d plane(s) each\n",
- q->num_buffers, num_planes);
+ buffer, num_planes);
return buffer;
}
@@ -205,12 +213,13 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
/**
* __vb2_free_mem() - release all video buffer memory for a given queue
*/
-static void __vb2_free_mem(struct vb2_queue *q)
+static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
{
unsigned int buffer;
struct vb2_buffer *vb;
- for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
+ ++buffer) {
vb = q->bufs[buffer];
if (!vb)
continue;
@@ -224,17 +233,18 @@ static void __vb2_free_mem(struct vb2_queue *q)
}
/**
- * __vb2_queue_free() - free the queue - video memory and related information
- * and return the queue to an uninitialized state. Might be called even if the
- * queue has already been freed.
+ * __vb2_queue_free() - free buffers at the end of the queue - video memory and
+ * related information, if no buffers are left return the queue to an
+ * uninitialized state. Might be called even if the queue has already been freed.
*/
-static void __vb2_queue_free(struct vb2_queue *q)
+static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
{
unsigned int buffer;
/* Call driver-provided cleanup function for each buffer, if provided */
if (q->ops->buf_cleanup) {
- for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
+ ++buffer) {
if (NULL == q->bufs[buffer])
continue;
q->ops->buf_cleanup(q->bufs[buffer]);
@@ -242,23 +252,25 @@ static void __vb2_queue_free(struct vb2_queue *q)
}
/* Release video buffer memory */
- __vb2_free_mem(q);
+ __vb2_free_mem(q, buffers);
/* Free videobuf buffers */
- for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
+ ++buffer) {
kfree(q->bufs[buffer]);
q->bufs[buffer] = NULL;
}
- q->num_buffers = 0;
- q->memory = 0;
+ q->num_buffers -= buffers;
+ if (!q->num_buffers)
+ q->memory = 0;
}
/**
* __verify_planes_array() - verify that the planes array passed in struct
* v4l2_buffer from userspace can be safely used
*/
-static int __verify_planes_array(struct vb2_buffer *vb, struct v4l2_buffer *b)
+static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b)
{
/* Is memory for copying plane information present? */
if (NULL == b->m.planes) {
@@ -318,7 +330,7 @@ static bool __buffers_in_use(struct vb2_queue *q)
static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
{
struct vb2_queue *q = vb->vb2_queue;
- int ret = 0;
+ int ret;
/* Copy back data such as timestamp, flags, input, etc. */
memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m));
@@ -365,8 +377,10 @@ static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
case VB2_BUF_STATE_DONE:
b->flags |= V4L2_BUF_FLAG_DONE;
break;
- case VB2_BUF_STATE_DEQUEUED:
case VB2_BUF_STATE_PREPARED:
+ b->flags |= V4L2_BUF_FLAG_PREPARED;
+ break;
+ case VB2_BUF_STATE_DEQUEUED:
/* nothing */
break;
}
@@ -374,7 +388,7 @@ static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
if (__buffer_in_use(q, vb))
b->flags |= V4L2_BUF_FLAG_MAPPED;
- return ret;
+ return 0;
}
/**
@@ -460,7 +474,7 @@ static int __verify_mmap_ops(struct vb2_queue *q)
*/
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
{
- unsigned int num_buffers, num_planes;
+ unsigned int num_buffers, allocated_buffers, num_planes = 0;
int ret = 0;
if (q->fileio) {
@@ -508,7 +522,7 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
return -EBUSY;
}
- __vb2_queue_free(q);
+ __vb2_queue_free(q, q->num_buffers);
/*
* In case of REQBUFS(0) return immediately without calling
@@ -542,44 +556,168 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
return -ENOMEM;
}
+ allocated_buffers = ret;
+
/*
* Check if driver can handle the allocated number of buffers.
*/
- if (ret < num_buffers) {
- unsigned int orig_num_buffers;
+ if (allocated_buffers < num_buffers) {
+ num_buffers = allocated_buffers;
- orig_num_buffers = num_buffers = ret;
ret = call_qop(q, queue_setup, q, NULL, &num_buffers,
&num_planes, q->plane_sizes, q->alloc_ctx);
- if (ret)
- goto free_mem;
- if (orig_num_buffers < num_buffers) {
+ if (!ret && allocated_buffers < num_buffers)
ret = -ENOMEM;
- goto free_mem;
- }
/*
- * Ok, driver accepted smaller number of buffers.
+ * Either the driver has accepted a smaller number of buffers,
+ * or .queue_setup() returned an error
*/
- ret = num_buffers;
+ }
+
+ q->num_buffers = allocated_buffers;
+
+ if (ret < 0) {
+ __vb2_queue_free(q, allocated_buffers);
+ return ret;
}
/*
* Return the number of successfully allocated buffers
* to the userspace.
*/
- req->count = ret;
+ req->count = allocated_buffers;
return 0;
-
-free_mem:
- __vb2_queue_free(q);
- return ret;
}
EXPORT_SYMBOL_GPL(vb2_reqbufs);
/**
+ * vb2_create_bufs() - Allocate buffers and any required auxiliary structs
+ * @q: videobuf2 queue
+ * @create: creation parameters, passed from userspace to vidioc_create_bufs
+ * handler in driver
+ *
+ * Should be called from vidioc_create_bufs ioctl handler of a driver.
+ * This function:
+ * 1) verifies parameter sanity
+ * 2) calls the .queue_setup() queue operation
+ * 3) performs any necessary memory allocations
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_create_bufs handler in driver.
+ */
+int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
+{
+ unsigned int num_planes = 0, num_buffers, allocated_buffers;
+ int ret = 0;
+
+ if (q->fileio) {
+ dprintk(1, "%s(): file io in progress\n", __func__);
+ return -EBUSY;
+ }
+
+ if (create->memory != V4L2_MEMORY_MMAP
+ && create->memory != V4L2_MEMORY_USERPTR) {
+ dprintk(1, "%s(): unsupported memory type\n", __func__);
+ return -EINVAL;
+ }
+
+ if (create->format.type != q->type) {
+ dprintk(1, "%s(): requested type is incorrect\n", __func__);
+ return -EINVAL;
+ }
+
+ /*
+ * Make sure all the required memory ops for given memory type
+ * are available.
+ */
+ if (create->memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) {
+ dprintk(1, "%s(): MMAP for current setup unsupported\n", __func__);
+ return -EINVAL;
+ }
+
+ if (create->memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
+ dprintk(1, "%s(): USERPTR for current setup unsupported\n", __func__);
+ return -EINVAL;
+ }
+
+ if (q->num_buffers == VIDEO_MAX_FRAME) {
+ dprintk(1, "%s(): maximum number of buffers already allocated\n",
+ __func__);
+ return -ENOBUFS;
+ }
+
+ create->index = q->num_buffers;
+
+ if (!q->num_buffers) {
+ memset(q->plane_sizes, 0, sizeof(q->plane_sizes));
+ memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
+ q->memory = create->memory;
+ }
+
+ num_buffers = min(create->count, VIDEO_MAX_FRAME - q->num_buffers);
+
+ /*
+ * Ask the driver, whether the requested number of buffers, planes per
+ * buffer and their sizes are acceptable
+ */
+ ret = call_qop(q, queue_setup, q, &create->format, &num_buffers,
+ &num_planes, q->plane_sizes, q->alloc_ctx);
+ if (ret)
+ return ret;
+
+ /* Finally, allocate buffers and video memory */
+ ret = __vb2_queue_alloc(q, create->memory, num_buffers,
+ num_planes);
+ if (ret < 0) {
+ dprintk(1, "Memory allocation failed with error: %d\n", ret);
+ return ret;
+ }
+
+ allocated_buffers = ret;
+
+ /*
+ * Check if driver can handle the so far allocated number of buffers.
+ */
+ if (ret < num_buffers) {
+ num_buffers = ret;
+
+ /*
+ * q->num_buffers contains the total number of buffers, that the
+ * queue driver has set up
+ */
+ ret = call_qop(q, queue_setup, q, &create->format, &num_buffers,
+ &num_planes, q->plane_sizes, q->alloc_ctx);
+
+ if (!ret && allocated_buffers < num_buffers)
+ ret = -ENOMEM;
+
+ /*
+ * Either the driver has accepted a smaller number of buffers,
+ * or .queue_setup() returned an error
+ */
+ }
+
+ q->num_buffers += allocated_buffers;
+
+ if (ret < 0) {
+ __vb2_queue_free(q, allocated_buffers);
+ return ret;
+ }
+
+ /*
+ * Return the number of successfully allocated buffers
+ * to the userspace.
+ */
+ create->count = allocated_buffers;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vb2_create_bufs);
+
+/**
* vb2_plane_vaddr() - Return a kernel virtual address of a given plane
* @vb: vb2_buffer to which the plane in question belongs to
* @plane_no: plane number for which the address is to be returned
@@ -663,7 +801,7 @@ EXPORT_SYMBOL_GPL(vb2_buffer_done);
* __fill_vb2_buffer() - fill a vb2_buffer with information provided in
* a v4l2_buffer by the userspace
*/
-static int __fill_vb2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b,
+static int __fill_vb2_buffer(struct vb2_buffer *vb, const struct v4l2_buffer *b,
struct v4l2_plane *v4l2_planes)
{
unsigned int plane;
@@ -727,7 +865,7 @@ static int __fill_vb2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b,
/**
* __qbuf_userptr() - handle qbuf of a USERPTR buffer
*/
-static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b)
+static int __qbuf_userptr(struct vb2_buffer *vb, const struct v4l2_buffer *b)
{
struct v4l2_plane planes[VIDEO_MAX_PLANES];
struct vb2_queue *q = vb->vb2_queue;
@@ -816,7 +954,7 @@ err:
/**
* __qbuf_mmap() - handle qbuf of an MMAP buffer
*/
-static int __qbuf_mmap(struct vb2_buffer *vb, struct v4l2_buffer *b)
+static int __qbuf_mmap(struct vb2_buffer *vb, const struct v4l2_buffer *b)
{
return __fill_vb2_buffer(vb, b, vb->v4l2_planes);
}
@@ -833,7 +971,7 @@ static void __enqueue_in_driver(struct vb2_buffer *vb)
q->ops->buf_queue(vb);
}
-static int __buf_prepare(struct vb2_buffer *vb, struct v4l2_buffer *b)
+static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b)
{
struct vb2_queue *q = vb->vb2_queue;
int ret;
@@ -861,6 +999,68 @@ static int __buf_prepare(struct vb2_buffer *vb, struct v4l2_buffer *b)
}
/**
+ * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
+ * @q: videobuf2 queue
+ * @b: buffer structure passed from userspace to vidioc_prepare_buf
+ * handler in driver
+ *
+ * Should be called from vidioc_prepare_buf ioctl handler of a driver.
+ * This function:
+ * 1) verifies the passed buffer,
+ * 2) calls buf_prepare callback in the driver (if provided), in which
+ * driver-specific buffer initialization can be performed,
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_prepare_buf handler in driver.
+ */
+int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
+{
+ struct vb2_buffer *vb;
+ int ret;
+
+ if (q->fileio) {
+ dprintk(1, "%s(): file io in progress\n", __func__);
+ return -EBUSY;
+ }
+
+ if (b->type != q->type) {
+ dprintk(1, "%s(): invalid buffer type\n", __func__);
+ return -EINVAL;
+ }
+
+ if (b->index >= q->num_buffers) {
+ dprintk(1, "%s(): buffer index out of range\n", __func__);
+ return -EINVAL;
+ }
+
+ vb = q->bufs[b->index];
+ if (NULL == vb) {
+ /* Should never happen */
+ dprintk(1, "%s(): buffer is NULL\n", __func__);
+ return -EINVAL;
+ }
+
+ if (b->memory != q->memory) {
+ dprintk(1, "%s(): invalid memory type\n", __func__);
+ return -EINVAL;
+ }
+
+ if (vb->state != VB2_BUF_STATE_DEQUEUED) {
+ dprintk(1, "%s(): invalid buffer state %d\n", __func__, vb->state);
+ return -EINVAL;
+ }
+
+ ret = __buf_prepare(vb, b);
+ if (ret < 0)
+ return ret;
+
+ __fill_v4l2_buffer(vb, b);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vb2_prepare_buf);
+
+/**
* vb2_qbuf() - Queue a buffer from userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_qbuf handler
@@ -1484,7 +1684,7 @@ void vb2_queue_release(struct vb2_queue *q)
{
__vb2_cleanup_fileio(q);
__vb2_queue_cancel(q);
- __vb2_queue_free(q);
+ __vb2_queue_free(q, q->num_buffers);
}
EXPORT_SYMBOL_GPL(vb2_queue_release);
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 692e35c232a9..55c57d3d3e63 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -169,13 +169,21 @@ struct vb2_buffer {
/**
* struct vb2_ops - driver-specific callbacks
*
- * @queue_setup: called from a VIDIOC_REQBUFS handler, before
- * memory allocation; driver should return the required
- * number of buffers in num_buffers, the required number
- * of planes per buffer in num_planes; the size of each
- * plane should be set in the sizes[] array and optional
- * per-plane allocator specific context in alloc_ctxs[]
- * array
+ * @queue_setup: called from VIDIOC_REQBUFS and VIDIOC_CREATE_BUFS
+ * handlers before memory allocation, or, if
+ * *num_planes != 0, after the allocation to verify a
+ * smaller number of buffers. Driver should return
+ * the required number of buffers in *num_buffers, the
+ * required number of planes per buffer in *num_planes; the
+ * size of each plane should be set in the sizes[] array
+ * and optional per-plane allocator specific context in the
+ * alloc_ctxs[] array. When called from VIDIOC_REQBUFS,
+ * fmt == NULL, the driver has to use the currently
+ * configured format and *num_buffers is the total number
+ * of buffers, that are being allocated. When called from
+ * VIDIOC_CREATE_BUFS, fmt != NULL and it describes the
+ * target frame format. In this case *num_buffers are being
+ * allocated additionally to q->num_buffers.
* @wait_prepare: release any locks taken while calling vb2 functions;
* it is called before an ioctl needs to wait for a new
* buffer to arrive; required to avoid a deadlock in
@@ -188,11 +196,11 @@ struct vb2_buffer {
* perform additional buffer-related initialization;
* initialization failure (return != 0) will prevent
* queue setup from completing successfully; optional
- * @buf_prepare: called every time the buffer is queued from userspace;
- * drivers may perform any initialization required before
- * each hardware operation in this callback;
- * if an error is returned, the buffer will not be queued
- * in driver; optional
+ * @buf_prepare: called every time the buffer is queued from userspace
+ * and from the VIDIOC_PREPARE_BUF ioctl; drivers may
+ * perform any initialization required before each hardware
+ * operation in this callback; if an error is returned, the
+ * buffer will not be queued in driver; optional
* @buf_finish: called before every dequeue of the buffer back to
* userspace; drivers may perform any operations required
* before userspace accesses the buffer; optional
@@ -300,6 +308,9 @@ int vb2_wait_for_all_buffers(struct vb2_queue *q);
int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
+int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create);
+int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b);
+
int vb2_queue_init(struct vb2_queue *q);
void vb2_queue_release(struct vb2_queue *q);

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