diff options
Diffstat (limited to 'drivers/media/v4l2-core/videobuf2-core.c')
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-core.c | 3464 |
1 files changed, 3464 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c new file mode 100644 index 00000000000..7c4489c4236 --- /dev/null +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -0,0 +1,3464 @@ +/* + * videobuf2-core.c - V4L2 driver helper framework + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak <pawel@osciak.com> + * Marek Szyprowski <m.szyprowski@samsung.com> + * + * The vb2_thread implementation was based on code from videobuf-dvb.c: + * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs] + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/freezer.h> +#include <linux/kthread.h> + +#include <media/v4l2-dev.h> +#include <media/v4l2-fh.h> +#include <media/v4l2-event.h> +#include <media/v4l2-common.h> +#include <media/videobuf2-core.h> + +static int debug; +module_param(debug, int, 0644); + +#define dprintk(level, fmt, arg...) \ + do { \ + if (debug >= level) \ + pr_debug("vb2: %s: " fmt, __func__, ## arg); \ + } while (0) + +#ifdef CONFIG_VIDEO_ADV_DEBUG + +/* + * If advanced debugging is on, then count how often each op is called + * successfully, which can either be per-buffer or per-queue. + * + * This makes it easy to check that the 'init' and 'cleanup' + * (and variations thereof) stay balanced. + */ + +#define log_memop(vb, op) \ + dprintk(2, "call_memop(%p, %d, %s)%s\n", \ + (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \ + (vb)->vb2_queue->mem_ops->op ? "" : " (nop)") + +#define call_memop(vb, op, args...) \ +({ \ + struct vb2_queue *_q = (vb)->vb2_queue; \ + int err; \ + \ + log_memop(vb, op); \ + err = _q->mem_ops->op ? _q->mem_ops->op(args) : 0; \ + if (!err) \ + (vb)->cnt_mem_ ## op++; \ + err; \ +}) + +#define call_ptr_memop(vb, op, args...) \ +({ \ + struct vb2_queue *_q = (vb)->vb2_queue; \ + void *ptr; \ + \ + log_memop(vb, op); \ + ptr = _q->mem_ops->op ? _q->mem_ops->op(args) : NULL; \ + if (!IS_ERR_OR_NULL(ptr)) \ + (vb)->cnt_mem_ ## op++; \ + ptr; \ +}) + +#define call_void_memop(vb, op, args...) \ +({ \ + struct vb2_queue *_q = (vb)->vb2_queue; \ + \ + log_memop(vb, op); \ + if (_q->mem_ops->op) \ + _q->mem_ops->op(args); \ + (vb)->cnt_mem_ ## op++; \ +}) + +#define log_qop(q, op) \ + dprintk(2, "call_qop(%p, %s)%s\n", q, #op, \ + (q)->ops->op ? "" : " (nop)") + +#define call_qop(q, op, args...) \ +({ \ + int err; \ + \ + log_qop(q, op); \ + err = (q)->ops->op ? (q)->ops->op(args) : 0; \ + if (!err) \ + (q)->cnt_ ## op++; \ + err; \ +}) + +#define call_void_qop(q, op, args...) \ +({ \ + log_qop(q, op); \ + if ((q)->ops->op) \ + (q)->ops->op(args); \ + (q)->cnt_ ## op++; \ +}) + +#define log_vb_qop(vb, op, args...) \ + dprintk(2, "call_vb_qop(%p, %d, %s)%s\n", \ + (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \ + (vb)->vb2_queue->ops->op ? "" : " (nop)") + +#define call_vb_qop(vb, op, args...) \ +({ \ + int err; \ + \ + log_vb_qop(vb, op); \ + err = (vb)->vb2_queue->ops->op ? \ + (vb)->vb2_queue->ops->op(args) : 0; \ + if (!err) \ + (vb)->cnt_ ## op++; \ + err; \ +}) + +#define call_void_vb_qop(vb, op, args...) \ +({ \ + log_vb_qop(vb, op); \ + if ((vb)->vb2_queue->ops->op) \ + (vb)->vb2_queue->ops->op(args); \ + (vb)->cnt_ ## op++; \ +}) + +#else + +#define call_memop(vb, op, args...) \ + ((vb)->vb2_queue->mem_ops->op ? \ + (vb)->vb2_queue->mem_ops->op(args) : 0) + +#define call_ptr_memop(vb, op, args...) \ + ((vb)->vb2_queue->mem_ops->op ? \ + (vb)->vb2_queue->mem_ops->op(args) : NULL) + +#define call_void_memop(vb, op, args...) \ + do { \ + if ((vb)->vb2_queue->mem_ops->op) \ + (vb)->vb2_queue->mem_ops->op(args); \ + } while (0) + +#define call_qop(q, op, args...) \ + ((q)->ops->op ? (q)->ops->op(args) : 0) + +#define call_void_qop(q, op, args...) \ + do { \ + if ((q)->ops->op) \ + (q)->ops->op(args); \ + } while (0) + +#define call_vb_qop(vb, op, args...) \ + ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0) + +#define call_void_vb_qop(vb, op, args...) \ + do { \ + if ((vb)->vb2_queue->ops->op) \ + (vb)->vb2_queue->ops->op(args); \ + } while (0) + +#endif + +/* Flags that are set by the vb2 core */ +#define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \ + V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \ + V4L2_BUF_FLAG_PREPARED | \ + V4L2_BUF_FLAG_TIMESTAMP_MASK) +/* Output buffer flags that should be passed on to the driver */ +#define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \ + V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE) + +static void __vb2_queue_cancel(struct vb2_queue *q); + +/** + * __vb2_buf_mem_alloc() - allocate video memory for the given buffer + */ +static int __vb2_buf_mem_alloc(struct vb2_buffer *vb) +{ + struct vb2_queue *q = vb->vb2_queue; + void *mem_priv; + int plane; + + /* + * Allocate memory for all planes in this buffer + * NOTE: mmapped areas should be page aligned + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + unsigned long size = PAGE_ALIGN(q->plane_sizes[plane]); + + mem_priv = call_ptr_memop(vb, alloc, q->alloc_ctx[plane], + size, q->gfp_flags); + if (IS_ERR_OR_NULL(mem_priv)) + goto free; + + /* Associate allocator private data with this plane */ + vb->planes[plane].mem_priv = mem_priv; + vb->v4l2_planes[plane].length = q->plane_sizes[plane]; + } + + return 0; +free: + /* Free already allocated memory if one of the allocations failed */ + for (; plane > 0; --plane) { + call_void_memop(vb, put, vb->planes[plane - 1].mem_priv); + vb->planes[plane - 1].mem_priv = NULL; + } + + return -ENOMEM; +} + +/** + * __vb2_buf_mem_free() - free memory of the given buffer + */ +static void __vb2_buf_mem_free(struct vb2_buffer *vb) +{ + unsigned int plane; + + for (plane = 0; plane < vb->num_planes; ++plane) { + call_void_memop(vb, put, vb->planes[plane].mem_priv); + vb->planes[plane].mem_priv = NULL; + dprintk(3, "freed plane %d of buffer %d\n", plane, + vb->v4l2_buf.index); + } +} + +/** + * __vb2_buf_userptr_put() - release userspace memory associated with + * a USERPTR buffer + */ +static void __vb2_buf_userptr_put(struct vb2_buffer *vb) +{ + unsigned int plane; + + for (plane = 0; plane < vb->num_planes; ++plane) { + if (vb->planes[plane].mem_priv) + call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv); + vb->planes[plane].mem_priv = NULL; + } +} + +/** + * __vb2_plane_dmabuf_put() - release memory associated with + * a DMABUF shared plane + */ +static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p) +{ + if (!p->mem_priv) + return; + + if (p->dbuf_mapped) + call_void_memop(vb, unmap_dmabuf, p->mem_priv); + + call_void_memop(vb, detach_dmabuf, p->mem_priv); + dma_buf_put(p->dbuf); + memset(p, 0, sizeof(*p)); +} + +/** + * __vb2_buf_dmabuf_put() - release memory associated with + * a DMABUF shared buffer + */ +static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb) +{ + unsigned int plane; + + for (plane = 0; plane < vb->num_planes; ++plane) + __vb2_plane_dmabuf_put(vb, &vb->planes[plane]); +} + +/** + * __setup_lengths() - setup initial lengths for every plane in + * every buffer on the queue + */ +static void __setup_lengths(struct vb2_queue *q, unsigned int n) +{ + unsigned int buffer, plane; + struct vb2_buffer *vb; + + for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) { + vb = q->bufs[buffer]; + if (!vb) + continue; + + for (plane = 0; plane < vb->num_planes; ++plane) + vb->v4l2_planes[plane].length = q->plane_sizes[plane]; + } +} + +/** + * __setup_offsets() - setup unique offsets ("cookies") for every plane in + * every buffer on the queue + */ +static void __setup_offsets(struct vb2_queue *q, unsigned int n) +{ + unsigned int buffer, plane; + struct vb2_buffer *vb; + unsigned long off; + + 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; + + for (plane = 0; plane < vb->num_planes; ++plane) { + vb->v4l2_planes[plane].m.mem_offset = off; + + dprintk(3, "buffer %d, plane %d offset 0x%08lx\n", + buffer, plane, off); + + off += vb->v4l2_planes[plane].length; + off = PAGE_ALIGN(off); + } + } +} + +/** + * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type) + * video buffer memory for all buffers/planes on the queue and initializes the + * queue + * + * Returns the number of buffers successfully allocated. + */ +static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory, + unsigned int num_buffers, unsigned int num_planes) +{ + unsigned int buffer; + struct vb2_buffer *vb; + int ret; + + for (buffer = 0; buffer < num_buffers; ++buffer) { + /* Allocate videobuf buffer structures */ + vb = kzalloc(q->buf_struct_size, GFP_KERNEL); + if (!vb) { + dprintk(1, "memory alloc for buffer struct failed\n"); + break; + } + + /* Length stores number of planes for multiplanar buffers */ + if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) + vb->v4l2_buf.length = num_planes; + + vb->state = VB2_BUF_STATE_DEQUEUED; + vb->vb2_queue = q; + vb->num_planes = num_planes; + vb->v4l2_buf.index = q->num_buffers + buffer; + vb->v4l2_buf.type = q->type; + vb->v4l2_buf.memory = memory; + + /* Allocate video buffer memory for the MMAP type */ + if (memory == V4L2_MEMORY_MMAP) { + ret = __vb2_buf_mem_alloc(vb); + if (ret) { + dprintk(1, "failed allocating memory for " + "buffer %d\n", buffer); + kfree(vb); + break; + } + /* + * Call the driver-provided buffer initialization + * callback, if given. An error in initialization + * results in queue setup failure. + */ + ret = call_vb_qop(vb, buf_init, vb); + if (ret) { + dprintk(1, "buffer %d %p initialization" + " failed\n", buffer, vb); + __vb2_buf_mem_free(vb); + kfree(vb); + break; + } + } + + q->bufs[q->num_buffers + buffer] = vb; + } + + __setup_lengths(q, buffer); + if (memory == V4L2_MEMORY_MMAP) + __setup_offsets(q, buffer); + + dprintk(1, "allocated %d buffers, %d plane(s) each\n", + buffer, num_planes); + + return buffer; +} + +/** + * __vb2_free_mem() - release all video buffer memory for a given queue + */ +static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers) +{ + unsigned int buffer; + struct vb2_buffer *vb; + + for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; + ++buffer) { + vb = q->bufs[buffer]; + if (!vb) + continue; + + /* Free MMAP buffers or release USERPTR buffers */ + if (q->memory == V4L2_MEMORY_MMAP) + __vb2_buf_mem_free(vb); + else if (q->memory == V4L2_MEMORY_DMABUF) + __vb2_buf_dmabuf_put(vb); + else + __vb2_buf_userptr_put(vb); + } +} + +/** + * __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 int __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) +{ + unsigned int buffer; + + /* + * Sanity check: when preparing a buffer the queue lock is released for + * a short while (see __buf_prepare for the details), which would allow + * a race with a reqbufs which can call this function. Removing the + * buffers from underneath __buf_prepare is obviously a bad idea, so we + * check if any of the buffers is in the state PREPARING, and if so we + * just return -EAGAIN. + */ + for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; + ++buffer) { + if (q->bufs[buffer] == NULL) + continue; + if (q->bufs[buffer]->state == VB2_BUF_STATE_PREPARING) { + dprintk(1, "preparing buffers, cannot free\n"); + return -EAGAIN; + } + } + + /* 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]; + + if (vb && vb->planes[0].mem_priv) + call_void_vb_qop(vb, buf_cleanup, vb); + } + + /* Release video buffer memory */ + __vb2_free_mem(q, buffers); + +#ifdef CONFIG_VIDEO_ADV_DEBUG + /* + * Check that all the calls were balances during the life-time of this + * queue. If not (or if the debug level is 1 or up), then dump the + * counters to the kernel log. + */ + if (q->num_buffers) { + bool unbalanced = q->cnt_start_streaming != q->cnt_stop_streaming || + q->cnt_wait_prepare != q->cnt_wait_finish; + + if (unbalanced || debug) { + pr_info("vb2: counters for queue %p:%s\n", q, + unbalanced ? " UNBALANCED!" : ""); + pr_info("vb2: setup: %u start_streaming: %u stop_streaming: %u\n", + q->cnt_queue_setup, q->cnt_start_streaming, + q->cnt_stop_streaming); + pr_info("vb2: wait_prepare: %u wait_finish: %u\n", + q->cnt_wait_prepare, q->cnt_wait_finish); + } + q->cnt_queue_setup = 0; + q->cnt_wait_prepare = 0; + q->cnt_wait_finish = 0; + q->cnt_start_streaming = 0; + q->cnt_stop_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; + + if (unbalanced || debug) { + pr_info("vb2: counters for queue %p, buffer %d:%s\n", + q, buffer, unbalanced ? " UNBALANCED!" : ""); + pr_info("vb2: buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n", + vb->cnt_buf_init, vb->cnt_buf_cleanup, + vb->cnt_buf_prepare, vb->cnt_buf_finish); + pr_info("vb2: buf_queue: %u buf_done: %u\n", + vb->cnt_buf_queue, vb->cnt_buf_done); + pr_info("vb2: alloc: %u put: %u prepare: %u finish: %u mmap: %u\n", + vb->cnt_mem_alloc, vb->cnt_mem_put, + vb->cnt_mem_prepare, vb->cnt_mem_finish, + vb->cnt_mem_mmap); + pr_info("vb2: get_userptr: %u put_userptr: %u\n", + vb->cnt_mem_get_userptr, vb->cnt_mem_put_userptr); + pr_info("vb2: attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n", + vb->cnt_mem_attach_dmabuf, vb->cnt_mem_detach_dmabuf, + vb->cnt_mem_map_dmabuf, vb->cnt_mem_unmap_dmabuf); + pr_info("vb2: get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n", + vb->cnt_mem_get_dmabuf, + vb->cnt_mem_num_users, + vb->cnt_mem_vaddr, + vb->cnt_mem_cookie); + } + } +#endif + + /* Free videobuf buffers */ + for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; + ++buffer) { + kfree(q->bufs[buffer]); + q->bufs[buffer] = NULL; + } + + q->num_buffers -= buffers; + if (!q->num_buffers) { + q->memory = 0; + INIT_LIST_HEAD(&q->queued_list); + } + return 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, const struct v4l2_buffer *b) +{ + if (!V4L2_TYPE_IS_MULTIPLANAR(b->type)) + return 0; + + /* Is memory for copying plane information present? */ + if (NULL == b->m.planes) { + dprintk(1, "multi-planar buffer passed but " + "planes array not provided\n"); + return -EINVAL; + } + + if (b->length < vb->num_planes || b->length > VIDEO_MAX_PLANES) { + dprintk(1, "incorrect planes array length, " + "expected %d, got %d\n", vb->num_planes, b->length); + return -EINVAL; + } + + return 0; +} + +/** + * __verify_length() - Verify that the bytesused value for each plane fits in + * the plane length and that the data offset doesn't exceed the bytesused value. + */ +static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + unsigned int length; + unsigned int plane; + + if (!V4L2_TYPE_IS_OUTPUT(b->type)) + return 0; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + for (plane = 0; plane < vb->num_planes; ++plane) { + length = (b->memory == V4L2_MEMORY_USERPTR) + ? b->m.planes[plane].length + : vb->v4l2_planes[plane].length; + + if (b->m.planes[plane].bytesused > length) + return -EINVAL; + + if (b->m.planes[plane].data_offset > 0 && + b->m.planes[plane].data_offset >= + b->m.planes[plane].bytesused) + return -EINVAL; + } + } else { + length = (b->memory == V4L2_MEMORY_USERPTR) + ? b->length : vb->v4l2_planes[0].length; + + if (b->bytesused > length) + return -EINVAL; + } + + return 0; +} + +/** + * __buffer_in_use() - return true if the buffer is in use and + * the queue cannot be freed (by the means of REQBUFS(0)) call + */ +static bool __buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb) +{ + unsigned int plane; + for (plane = 0; plane < vb->num_planes; ++plane) { + void *mem_priv = vb->planes[plane].mem_priv; + /* + * If num_users() has not been provided, call_memop + * will return 0, apparently nobody cares about this + * case anyway. If num_users() returns more than 1, + * we are not the only user of the plane's memory. + */ + if (mem_priv && call_memop(vb, num_users, mem_priv) > 1) + return true; + } + return false; +} + +/** + * __buffers_in_use() - return true if any buffers on the queue are in use and + * the queue cannot be freed (by the means of REQBUFS(0)) call + */ +static bool __buffers_in_use(struct vb2_queue *q) +{ + unsigned int buffer; + for (buffer = 0; buffer < q->num_buffers; ++buffer) { + if (__buffer_in_use(q, q->bufs[buffer])) + return true; + } + return false; +} + +/** + * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be + * returned to userspace + */ +static void __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) +{ + struct vb2_queue *q = vb->vb2_queue; + + /* Copy back data such as timestamp, flags, etc. */ + memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m)); + b->reserved2 = vb->v4l2_buf.reserved2; + b->reserved = vb->v4l2_buf.reserved; + + if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) { + /* + * Fill in plane-related data if userspace provided an array + * for it. The caller has already verified memory and size. + */ + b->length = vb->num_planes; + memcpy(b->m.planes, vb->v4l2_planes, + b->length * sizeof(struct v4l2_plane)); + } else { + /* + * We use length and offset in v4l2_planes array even for + * single-planar buffers, but userspace does not. + */ + b->length = vb->v4l2_planes[0].length; + b->bytesused = vb->v4l2_planes[0].bytesused; + if (q->memory == V4L2_MEMORY_MMAP) + b->m.offset = vb->v4l2_planes[0].m.mem_offset; + else if (q->memory == V4L2_MEMORY_USERPTR) + b->m.userptr = vb->v4l2_planes[0].m.userptr; + else if (q->memory == V4L2_MEMORY_DMABUF) + b->m.fd = vb->v4l2_planes[0].m.fd; + } + + /* + * Clear any buffer state related flags. + */ + b->flags &= ~V4L2_BUFFER_MASK_FLAGS; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK; + if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) != + V4L2_BUF_FLAG_TIMESTAMP_COPY) { + /* + * For non-COPY timestamps, drop timestamp source bits + * and obtain the timestamp source from the queue. + */ + b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + switch (vb->state) { + case VB2_BUF_STATE_QUEUED: + case VB2_BUF_STATE_ACTIVE: + b->flags |= V4L2_BUF_FLAG_QUEUED; + break; + case VB2_BUF_STATE_ERROR: + b->flags |= V4L2_BUF_FLAG_ERROR; + /* fall through */ + case VB2_BUF_STATE_DONE: + b->flags |= V4L2_BUF_FLAG_DONE; + break; + case VB2_BUF_STATE_PREPARED: + b->flags |= V4L2_BUF_FLAG_PREPARED; + break; + case VB2_BUF_STATE_PREPARING: + case VB2_BUF_STATE_DEQUEUED: + /* nothing */ + break; + } + + if (__buffer_in_use(q, vb)) + b->flags |= V4L2_BUF_FLAG_MAPPED; +} + +/** + * vb2_querybuf() - query video buffer information + * @q: videobuf queue + * @b: buffer struct passed from userspace to vidioc_querybuf handler + * in driver + * + * Should be called from vidioc_querybuf ioctl handler in driver. + * This function will verify the passed v4l2_buffer structure and fill the + * relevant information for the userspace. + * + * The return values from this function are intended to be directly returned + * from vidioc_querybuf handler in driver. + */ +int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + struct vb2_buffer *vb; + int ret; + + if (b->type != q->type) { + dprintk(1, "wrong buffer type\n"); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "buffer index out of range\n"); + return -EINVAL; + } + vb = q->bufs[b->index]; + ret = __verify_planes_array(vb, b); + if (!ret) + __fill_v4l2_buffer(vb, b); + return ret; +} +EXPORT_SYMBOL(vb2_querybuf); + +/** + * __verify_userptr_ops() - verify that all memory operations required for + * USERPTR queue type have been provided + */ +static int __verify_userptr_ops(struct vb2_queue *q) +{ + if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr || + !q->mem_ops->put_userptr) + return -EINVAL; + + return 0; +} + +/** + * __verify_mmap_ops() - verify that all memory operations required for + * MMAP queue type have been provided + */ +static int __verify_mmap_ops(struct vb2_queue *q) +{ + if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc || + !q->mem_ops->put || !q->mem_ops->mmap) + return -EINVAL; + + return 0; +} + +/** + * __verify_dmabuf_ops() - verify that all memory operations required for + * DMABUF queue type have been provided + */ +static int __verify_dmabuf_ops(struct vb2_queue *q) +{ + if (!(q->io_modes & VB2_DMABUF) || !q->mem_ops->attach_dmabuf || + !q->mem_ops->detach_dmabuf || !q->mem_ops->map_dmabuf || + !q->mem_ops->unmap_dmabuf) + return -EINVAL; + + return 0; +} + +/** + * __verify_memory_type() - Check whether the memory type and buffer type + * passed to a buffer operation are compatible with the queue. + */ +static int __verify_memory_type(struct vb2_queue *q, + enum v4l2_memory memory, enum v4l2_buf_type type) +{ + if (memory != V4L2_MEMORY_MMAP && memory != V4L2_MEMORY_USERPTR && + memory != V4L2_MEMORY_DMABUF) { + dprintk(1, "unsupported memory type\n"); + return -EINVAL; + } + + if (type != q->type) { + dprintk(1, "requested type is incorrect\n"); + return -EINVAL; + } + + /* + * Make sure all the required memory ops for given memory type + * are available. + */ + if (memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) { + dprintk(1, "MMAP for current setup unsupported\n"); + return -EINVAL; + } + + if (memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) { + dprintk(1, "USERPTR for current setup unsupported\n"); + return -EINVAL; + } + + if (memory == V4L2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) { + dprintk(1, "DMABUF for current setup unsupported\n"); + return -EINVAL; + } + + /* + * Place the busy tests at the end: -EBUSY can be ignored when + * create_bufs is called with count == 0, but count == 0 should still + * do the memory and type validation. + */ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return 0; +} + +/** + * __reqbufs() - Initiate streaming + * @q: videobuf2 queue + * @req: struct passed from userspace to vidioc_reqbufs handler in driver + * + * Should be called from vidioc_reqbufs ioctl handler of a driver. + * This function: + * 1) verifies streaming parameters passed from the userspace, + * 2) sets up the queue, + * 3) negotiates number of buffers and planes per buffer with the driver + * to be used during streaming, + * 4) allocates internal buffer structures (struct vb2_buffer), according to + * the agreed parameters, + * 5) for MMAP memory type, allocates actual video memory, using the + * memory handling/allocation routines provided during queue initialization + * + * If req->count is 0, all the memory will be freed instead. + * If the queue has been allocated previously (by a previous vb2_reqbufs) call + * and the queue is not busy, memory will be reallocated. + * + * The return values from this function are intended to be directly returned + * from vidioc_reqbufs handler in driver. + */ +static int __reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) +{ + unsigned int num_buffers, allocated_buffers, num_planes = 0; + int ret; + + if (q->streaming) { + dprintk(1, "streaming active\n"); + return -EBUSY; + } + + if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) { + /* + * We already have buffers allocated, so first check if they + * are not in use and can be freed. + */ + if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) { + dprintk(1, "memory in use, cannot free\n"); + return -EBUSY; + } + + /* + * Call queue_cancel to clean up any buffers in the PREPARED or + * QUEUED state which is possible if buffers were prepared or + * queued without ever calling STREAMON. + */ + __vb2_queue_cancel(q); + ret = __vb2_queue_free(q, q->num_buffers); + if (ret) + return ret; + + /* + * In case of REQBUFS(0) return immediately without calling + * driver's queue_setup() callback and allocating resources. + */ + if (req->count == 0) + return 0; + } + + /* + * Make sure the requested values and current defaults are sane. + */ + num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME); + num_buffers = max_t(unsigned int, num_buffers, q->min_buffers_needed); + memset(q->plane_sizes, 0, sizeof(q->plane_sizes)); + memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx)); + q->memory = req->memory; + + /* + * Ask the driver how many buffers and planes per buffer it requires. + * Driver also sets the size and allocator context for each plane. + */ + ret = call_qop(q, queue_setup, q, NULL, &num_buffers, &num_planes, + q->plane_sizes, q->alloc_ctx); + if (ret) + return ret; + + /* Finally, allocate buffers and video memory */ + allocated_buffers = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes); + if (allocated_buffers == 0) { + dprintk(1, "memory allocation failed\n"); + return -ENOMEM; + } + + /* + * There is no point in continuing if we can't allocate the minimum + * number of buffers needed by this vb2_queue. + */ + if (allocated_buffers < q->min_buffers_needed) + ret = -ENOMEM; + + /* + * Check if driver can handle the allocated number of buffers. + */ + if (!ret && allocated_buffers < num_buffers) { + num_buffers = allocated_buffers; + + ret = call_qop(q, queue_setup, q, NULL, &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) { + /* + * Note: __vb2_queue_free() will subtract 'allocated_buffers' + * from q->num_buffers. + */ + __vb2_queue_free(q, allocated_buffers); + return ret; + } + + /* + * Return the number of successfully allocated buffers + * to the userspace. + */ + req->count = allocated_buffers; + + return 0; +} + +/** + * vb2_reqbufs() - Wrapper for __reqbufs() that also verifies the memory and + * type values. + * @q: videobuf2 queue + * @req: struct passed from userspace to vidioc_reqbufs handler in driver + */ +int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) +{ + int ret = __verify_memory_type(q, req->memory, req->type); + + return ret ? ret : __reqbufs(q, req); +} +EXPORT_SYMBOL_GPL(vb2_reqbufs); + +/** + * __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. + */ +static int __create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) +{ + unsigned int num_planes = 0, num_buffers, allocated_buffers; + int ret; + + if (q->num_buffers == VIDEO_MAX_FRAME) { + dprintk(1, "maximum number of buffers already allocated\n"); + return -ENOBUFS; + } + + 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 */ + allocated_buffers = __vb2_queue_alloc(q, create->memory, num_buffers, + num_planes); + if (allocated_buffers == 0) { + dprintk(1, "memory allocation failed\n"); + return -ENOMEM; + } + + /* + * Check if driver can handle the so far allocated number of buffers. + */ + if (allocated_buffers < num_buffers) { + num_buffers = allocated_buffers; + + /* + * 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) { + /* + * Note: __vb2_queue_free() will subtract 'allocated_buffers' + * from q->num_buffers. + */ + __vb2_queue_free(q, allocated_buffers); + return -ENOMEM; + } + + /* + * Return the number of successfully allocated buffers + * to the userspace. + */ + create->count = allocated_buffers; + + return 0; +} + +/** + * vb2_create_bufs() - Wrapper for __create_bufs() that also verifies the + * memory and type values. + * @q: videobuf2 queue + * @create: creation parameters, passed from userspace to vidioc_create_bufs + * handler in driver + */ +int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) +{ + int ret = __verify_memory_type(q, create->memory, create->format.type); + + create->index = q->num_buffers; + if (create->count == 0) + return ret != -EBUSY ? ret : 0; + return ret ? ret : __create_bufs(q, create); +} +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 + * + * This function returns a kernel virtual address of a given plane if + * such a mapping exist, NULL otherwise. + */ +void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no) +{ + if (plane_no > vb->num_planes || !vb->planes[plane_no].mem_priv) + return NULL; + + return call_ptr_memop(vb, vaddr, vb->planes[plane_no].mem_priv); + +} +EXPORT_SYMBOL_GPL(vb2_plane_vaddr); + +/** + * vb2_plane_cookie() - Return allocator specific cookie for the given plane + * @vb: vb2_buffer to which the plane in question belongs to + * @plane_no: plane number for which the cookie is to be returned + * + * This function returns an allocator specific cookie for a given plane if + * available, NULL otherwise. The allocator should provide some simple static + * inline function, which would convert this cookie to the allocator specific + * type that can be used directly by the driver to access the buffer. This can + * be for example physical address, pointer to scatter list or IOMMU mapping. + */ +void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no) +{ + if (plane_no > vb->num_planes || !vb->planes[plane_no].mem_priv) + return NULL; + + return call_ptr_memop(vb, cookie, vb->planes[plane_no].mem_priv); +} +EXPORT_SYMBOL_GPL(vb2_plane_cookie); + +/** + * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished + * @vb: vb2_buffer returned from the driver + * @state: either VB2_BUF_STATE_DONE if the operation finished successfully + * or VB2_BUF_STATE_ERROR if the operation finished with an error. + * If start_streaming fails then it should return buffers with state + * VB2_BUF_STATE_QUEUED to put them back into the queue. + * + * This function should be called by the driver after a hardware operation on + * a buffer is finished and the buffer may be returned to userspace. The driver + * cannot use this buffer anymore until it is queued back to it by videobuf + * by the means of buf_queue callback. Only buffers previously queued to the + * driver by buf_queue can be passed to this function. + * + * While streaming a buffer can only be returned in state DONE or ERROR. + * The start_streaming op can also return them in case the DMA engine cannot + * be started for some reason. In that case the buffers should be returned with + * state QUEUED. + */ +void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned long flags; + unsigned int plane; + + if (WARN_ON(vb->state != VB2_BUF_STATE_ACTIVE)) + return; + + if (!q->start_streaming_called) { + if (WARN_ON(state != VB2_BUF_STATE_QUEUED)) + state = VB2_BUF_STATE_QUEUED; + } else if (WARN_ON(state != VB2_BUF_STATE_DONE && + state != VB2_BUF_STATE_ERROR)) { + state = VB2_BUF_STATE_ERROR; + } + +#ifdef CONFIG_VIDEO_ADV_DEBUG + /* + * Although this is not a callback, it still does have to balance + * with the buf_queue op. So update this counter manually. + */ + vb->cnt_buf_done++; +#endif + dprintk(4, "done processing on buffer %d, state: %d\n", + vb->v4l2_buf.index, state); + + /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_void_memop(vb, finish, vb->planes[plane].mem_priv); + + /* Add the buffer to the done buffers list */ + spin_lock_irqsave(&q->done_lock, flags); + vb->state = state; + if (state != VB2_BUF_STATE_QUEUED) + list_add_tail(&vb->done_entry, &q->done_list); + atomic_dec(&q->owned_by_drv_count); + spin_unlock_irqrestore(&q->done_lock, flags); + + if (state == VB2_BUF_STATE_QUEUED) + return; + + /* Inform any processes that may be waiting for buffers */ + wake_up(&q->done_wq); +} +EXPORT_SYMBOL_GPL(vb2_buffer_done); + +/** + * vb2_discard_done() - discard all buffers marked as DONE + * @q: videobuf2 queue + * + * This function is intended to be used with suspend/resume operations. It + * discards all 'done' buffers as they would be too old to be requested after + * resume. + * + * Drivers must stop the hardware and synchronize with interrupt handlers and/or + * delayed works before calling this function to make sure no buffer will be + * touched by the driver and/or hardware. + */ +void vb2_discard_done(struct vb2_queue *q) +{ + struct vb2_buffer *vb; + unsigned long flags; + + spin_lock_irqsave(&q->done_lock, flags); + list_for_each_entry(vb, &q->done_list, done_entry) + vb->state = VB2_BUF_STATE_ERROR; + spin_unlock_irqrestore(&q->done_lock, flags); +} +EXPORT_SYMBOL_GPL(vb2_discard_done); + +/** + * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a + * v4l2_buffer by the userspace. The caller has already verified that struct + * v4l2_buffer has a valid number of planes. + */ +static void __fill_vb2_buffer(struct vb2_buffer *vb, const struct v4l2_buffer *b, + struct v4l2_plane *v4l2_planes) +{ + unsigned int plane; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + /* Fill in driver-provided information for OUTPUT types */ + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + bool bytesused_is_used; + + /* Check if bytesused == 0 for all planes */ + for (plane = 0; plane < vb->num_planes; ++plane) + if (b->m.planes[plane].bytesused) + break; + bytesused_is_used = plane < vb->num_planes; + + /* + * Will have to go up to b->length when API starts + * accepting variable number of planes. + * + * If bytesused_is_used is false, then fall back to the + * full buffer size. In that case userspace clearly + * never bothered to set it and it's a safe assumption + * that they really meant to use the full plane sizes. + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + struct v4l2_plane *pdst = &v4l2_planes[plane]; + struct v4l2_plane *psrc = &b->m.planes[plane]; + + pdst->bytesused = bytesused_is_used ? + psrc->bytesused : psrc->length; + pdst->data_offset = psrc->data_offset; + } + } + + if (b->memory == V4L2_MEMORY_USERPTR) { + for (plane = 0; plane < vb->num_planes; ++plane) { + v4l2_planes[plane].m.userptr = + b->m.planes[plane].m.userptr; + v4l2_planes[plane].length = + b->m.planes[plane].length; + } + } + if (b->memory == V4L2_MEMORY_DMABUF) { + for (plane = 0; plane < vb->num_planes; ++plane) { + v4l2_planes[plane].m.fd = + b->m.planes[plane].m.fd; + v4l2_planes[plane].length = + b->m.planes[plane].length; + } + } + } else { + /* + * Single-planar buffers do not use planes array, + * so fill in relevant v4l2_buffer struct fields instead. + * In videobuf we use our internal V4l2_planes struct for + * single-planar buffers as well, for simplicity. + * + * If bytesused == 0, then fall back to the full buffer size + * as that's a sensible default. + */ + if (V4L2_TYPE_IS_OUTPUT(b->type)) + v4l2_planes[0].bytesused = + b->bytesused ? b->bytesused : b->length; + else + v4l2_planes[0].bytesused = 0; + + if (b->memory == V4L2_MEMORY_USERPTR) { + v4l2_planes[0].m.userptr = b->m.userptr; + v4l2_planes[0].length = b->length; + } + + if (b->memory == V4L2_MEMORY_DMABUF) { + v4l2_planes[0].m.fd = b->m.fd; + v4l2_planes[0].length = b->length; + } + } + + /* Zero flags that the vb2 core handles */ + vb->v4l2_buf.flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS; + if ((vb->vb2_queue->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) != + V4L2_BUF_FLAG_TIMESTAMP_COPY || !V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * Non-COPY timestamps and non-OUTPUT queues will get + * their timestamp and timestamp source flags from the + * queue. + */ + vb->v4l2_buf.flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * For output buffers mask out the timecode flag: + * this will be handled later in vb2_internal_qbuf(). + * The 'field' is valid metadata for this output buffer + * and so that needs to be copied here. + */ + vb->v4l2_buf.flags &= ~V4L2_BUF_FLAG_TIMECODE; + vb->v4l2_buf.field = b->field; + } else { + /* Zero any output buffer flags as this is a capture buffer */ + vb->v4l2_buf.flags &= ~V4L2_BUFFER_OUT_FLAGS; + } +} + +/** + * __qbuf_mmap() - handle qbuf of an MMAP buffer + */ +static int __qbuf_mmap(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + __fill_vb2_buffer(vb, b, vb->v4l2_planes); + return call_vb_qop(vb, buf_prepare, vb); +} + +/** + * __qbuf_userptr() - handle qbuf of a USERPTR buffer + */ +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; + void *mem_priv; + unsigned int plane; + int ret; + int write = !V4L2_TYPE_IS_OUTPUT(q->type); + bool reacquired = vb->planes[0].mem_priv == NULL; + + memset(planes, 0, sizeof(planes[0]) * vb->num_planes); + /* Copy relevant information provided by the userspace */ + __fill_vb2_buffer(vb, b, planes); + + for (plane = 0; plane < vb->num_planes; ++plane) { + /* Skip the plane if already verified */ + if (vb->v4l2_planes[plane].m.userptr && + vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr + && vb->v4l2_planes[plane].length == planes[plane].length) + continue; + + dprintk(3, "userspace address for plane %d changed, " + "reacquiring memory\n", plane); + + /* Check if the provided plane buffer is large enough */ + if (planes[plane].length < q->plane_sizes[plane]) { + dprintk(1, "provided buffer size %u is less than " + "setup size %u for plane %d\n", + planes[plane].length, + q->plane_sizes[plane], plane); + ret = -EINVAL; + goto err; + } + + /* Release previously acquired memory if present */ + if (vb->planes[plane].mem_priv) { + if (!reacquired) { + reacquired = true; + call_void_vb_qop(vb, buf_cleanup, vb); + } + call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv); + } + + vb->planes[plane].mem_priv = NULL; + memset(&vb->v4l2_planes[plane], 0, sizeof(struct v4l2_plane)); + + /* Acquire each plane's memory */ + mem_priv = call_ptr_memop(vb, get_userptr, q->alloc_ctx[plane], + planes[plane].m.userptr, + planes[plane].length, write); + if (IS_ERR_OR_NULL(mem_priv)) { + dprintk(1, "failed acquiring userspace " + "memory for plane %d\n", plane); + ret = mem_priv ? PTR_ERR(mem_priv) : -EINVAL; + goto err; + } + vb->planes[plane].mem_priv = mem_priv; + } + + /* + * Now that everything is in order, copy relevant information + * provided by userspace. + */ + for (plane = 0; plane < vb->num_planes; ++plane) + vb->v4l2_planes[plane] = planes[plane]; + + if (reacquired) { + /* + * One or more planes changed, so we must call buf_init to do + * the driver-specific initialization on the newly acquired + * buffer, if provided. + */ + ret = call_vb_qop(vb, buf_init, vb); + if (ret) { + dprintk(1, "buffer initialization failed\n"); + goto err; + } + } + + ret = call_vb_qop(vb, buf_prepare, vb); + if (ret) { + dprintk(1, "buffer preparation failed\n"); + call_void_vb_qop(vb, buf_cleanup, vb); + goto err; + } + + return 0; +err: + /* In case of errors, release planes that were already acquired */ + for (plane = 0; plane < vb->num_planes; ++plane) { + if (vb->planes[plane].mem_priv) + call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv); + vb->planes[plane].mem_priv = NULL; + vb->v4l2_planes[plane].m.userptr = 0; + vb->v4l2_planes[plane].length = 0; + } + + return ret; +} + +/** + * __qbuf_dmabuf() - handle qbuf of a DMABUF buffer + */ +static int __qbuf_dmabuf(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + struct v4l2_plane planes[VIDEO_MAX_PLANES]; + struct vb2_queue *q = vb->vb2_queue; + void *mem_priv; + unsigned int plane; + int ret; + int write = !V4L2_TYPE_IS_OUTPUT(q->type); + bool reacquired = vb->planes[0].mem_priv == NULL; + + memset(planes, 0, sizeof(planes[0]) * vb->num_planes); + /* Copy relevant information provided by the userspace */ + __fill_vb2_buffer(vb, b, planes); + + for (plane = 0; plane < vb->num_planes; ++plane) { + struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd); + + if (IS_ERR_OR_NULL(dbuf)) { + dprintk(1, "invalid dmabuf fd for plane %d\n", + plane); + ret = -EINVAL; + goto err; + } + + /* use DMABUF size if length is not provided */ + if (planes[plane].length == 0) + planes[plane].length = dbuf->size; + + if (planes[plane].length < q->plane_sizes[plane]) { + dprintk(1, "invalid dmabuf length for plane %d\n", + plane); + ret = -EINVAL; + goto err; + } + + /* Skip the plane if already verified */ + if (dbuf == vb->planes[plane].dbuf && + vb->v4l2_planes[plane].length == planes[plane].length) { + dma_buf_put(dbuf); + continue; + } + + dprintk(1, "buffer for plane %d changed\n", plane); + + if (!reacquired) { + reacquired = true; + call_void_vb_qop(vb, buf_cleanup, vb); + } + + /* Release previously acquired memory if present */ + __vb2_plane_dmabuf_put(vb, &vb->planes[plane]); + memset(&vb->v4l2_planes[plane], 0, sizeof(struct v4l2_plane)); + + /* Acquire each plane's memory */ + mem_priv = call_ptr_memop(vb, attach_dmabuf, q->alloc_ctx[plane], + dbuf, planes[plane].length, write); + if (IS_ERR(mem_priv)) { + dprintk(1, "failed to attach dmabuf\n"); + ret = PTR_ERR(mem_priv); + dma_buf_put(dbuf); + goto err; + } + + vb->planes[plane].dbuf = dbuf; + vb->planes[plane].mem_priv = mem_priv; + } + + /* TODO: This pins the buffer(s) with dma_buf_map_attachment()).. but + * really we want to do this just before the DMA, not while queueing + * the buffer(s).. + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + ret = call_memop(vb, map_dmabuf, vb->planes[plane].mem_priv); + if (ret) { + dprintk(1, "failed to map dmabuf for plane %d\n", + plane); + goto err; + } + vb->planes[plane].dbuf_mapped = 1; + } + + /* + * Now that everything is in order, copy relevant information + * provided by userspace. + */ + for (plane = 0; plane < vb->num_planes; ++plane) + vb->v4l2_planes[plane] = planes[plane]; + + if (reacquired) { + /* + * Call driver-specific initialization on the newly acquired buffer, + * if provided. + */ + ret = call_vb_qop(vb, buf_init, vb); + if (ret) { + dprintk(1, "buffer initialization failed\n"); + goto err; + } + } + + ret = call_vb_qop(vb, buf_prepare, vb); + if (ret) { + dprintk(1, "buffer preparation failed\n"); + call_void_vb_qop(vb, buf_cleanup, vb); + goto err; + } + + return 0; +err: + /* In case of errors, release planes that were already acquired */ + __vb2_buf_dmabuf_put(vb); + + return ret; +} + +/** + * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing + */ +static void __enqueue_in_driver(struct vb2_buffer *vb) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + + vb->state = VB2_BUF_STATE_ACTIVE; + atomic_inc(&q->owned_by_drv_count); + + /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_void_memop(vb, prepare, vb->planes[plane].mem_priv); + + call_void_vb_qop(vb, buf_queue, vb); +} + +static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + struct vb2_queue *q = vb->vb2_queue; + struct rw_semaphore *mmap_sem; + int ret; + + ret = __verify_length(vb, b); + if (ret < 0) { + dprintk(1, "plane parameters verification failed: %d\n", ret); + return ret; + } + if (b->field == V4L2_FIELD_ALTERNATE && V4L2_TYPE_IS_OUTPUT(q->type)) { + /* + * If the format's field is ALTERNATE, then the buffer's field + * should be either TOP or BOTTOM, not ALTERNATE since that + * makes no sense. The driver has to know whether the + * buffer represents a top or a bottom field in order to + * program any DMA correctly. Using ALTERNATE is wrong, since + * that just says that it is either a top or a bottom field, + * but not which of the two it is. + */ + dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n"); + return -EINVAL; + } + + vb->state = VB2_BUF_STATE_PREPARING; + vb->v4l2_buf.timestamp.tv_sec = 0; + vb->v4l2_buf.timestamp.tv_usec = 0; + vb->v4l2_buf.sequence = 0; + + switch (q->memory) { + case V4L2_MEMORY_MMAP: + ret = __qbuf_mmap(vb, b); + break; + case V4L2_MEMORY_USERPTR: + /* + * In case of user pointer buffers vb2 allocators need to get + * direct access to userspace pages. This requires getting + * the mmap semaphore for read access in the current process + * structure. The same semaphore is taken before calling mmap + * operation, while both qbuf/prepare_buf and mmap are called + * by the driver or v4l2 core with the driver's lock held. + * To avoid an AB-BA deadlock (mmap_sem then driver's lock in + * mmap and driver's lock then mmap_sem in qbuf/prepare_buf), + * the videobuf2 core releases the driver's lock, takes + * mmap_sem and then takes the driver's lock again. + */ + mmap_sem = ¤t->mm->mmap_sem; + call_void_qop(q, wait_prepare, q); + down_read(mmap_sem); + call_void_qop(q, wait_finish, q); + + ret = __qbuf_userptr(vb, b); + + up_read(mmap_sem); + break; + case V4L2_MEMORY_DMABUF: + ret = __qbuf_dmabuf(vb, b); + break; + default: + WARN(1, "Invalid queue type\n"); + ret = -EINVAL; + } + + if (ret) + dprintk(1, "buffer preparation failed: %d\n", ret); + vb->state = ret ? VB2_BUF_STATE_DEQUEUED : VB2_BUF_STATE_PREPARED; + + return ret; +} + +static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b, + const char *opname) +{ + if (b->type != q->type) { + dprintk(1, "%s: invalid buffer type\n", opname); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "%s: buffer index out of range\n", opname); + return -EINVAL; + } + + if (q->bufs[b->index] == NULL) { + /* Should never happen */ + dprintk(1, "%s: buffer is NULL\n", opname); + return -EINVAL; + } + + if (b->memory != q->memory) { + dprintk(1, "%s: invalid memory type\n", opname); + return -EINVAL; + } + + return __verify_planes_array(q->bufs[b->index], 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 (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + ret = vb2_queue_or_prepare_buf(q, b, "prepare_buf"); + if (ret) + return ret; + + vb = q->bufs[b->index]; + if (vb->state != VB2_BUF_STATE_DEQUEUED) { + dprintk(1, "invalid buffer state %d\n", + vb->state); + return -EINVAL; + } + + ret = __buf_prepare(vb, b); + if (!ret) { + /* Fill buffer information for the userspace */ + __fill_v4l2_buffer(vb, b); + + dprintk(1, "prepare of buffer %d succeeded\n", vb->v4l2_buf.index); + } + return ret; +} +EXPORT_SYMBOL_GPL(vb2_prepare_buf); + +/** + * vb2_start_streaming() - Attempt to start streaming. + * @q: videobuf2 queue + * + * Attempt to start streaming. When this function is called there must be + * at least q->min_buffers_needed buffers queued up (i.e. the minimum + * number of buffers required for the DMA engine to function). If the + * @start_streaming op fails it is supposed to return all the driver-owned + * buffers back to vb2 in state QUEUED. Check if that happened and if + * not warn and reclaim them forcefully. + */ +static int vb2_start_streaming(struct vb2_queue *q) +{ + struct vb2_buffer *vb; + int ret; + + /* + * If any buffers were queued before streamon, + * we can now pass them to driver for processing. + */ + list_for_each_entry(vb, &q->queued_list, queued_entry) + __enqueue_in_driver(vb); + + /* Tell the driver to start streaming */ + ret = call_qop(q, start_streaming, q, + atomic_read(&q->owned_by_drv_count)); + q->start_streaming_called = ret == 0; + if (!ret) + return 0; + + dprintk(1, "driver refused to start streaming\n"); + if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { + unsigned i; + + /* + * Forcefully reclaim buffers if the driver did not + * correctly return them to vb2. + */ + for (i = 0; i < q->num_buffers; ++i) { + vb = q->bufs[i]; + if (vb->state == VB2_BUF_STATE_ACTIVE) + vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED); + } + /* Must be zero now */ + WARN_ON(atomic_read(&q->owned_by_drv_count)); + } + return ret; +} + +static int vb2_internal_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + int ret = vb2_queue_or_prepare_buf(q, b, "qbuf"); + struct vb2_buffer *vb; + + if (ret) + return ret; + + vb = q->bufs[b->index]; + + switch (vb->state) { + case VB2_BUF_STATE_DEQUEUED: + ret = __buf_prepare(vb, b); + if (ret) + return ret; + break; + case VB2_BUF_STATE_PREPARED: + break; + case VB2_BUF_STATE_PREPARING: + dprintk(1, "buffer still being prepared\n"); + return -EINVAL; + default: + dprintk(1, "invalid buffer state %d\n", vb->state); + return -EINVAL; + } + + /* + * Add to the queued buffers list, a buffer will stay on it until + * dequeued in dqbuf. + */ + list_add_tail(&vb->queued_entry, &q->queued_list); + q->queued_count++; + vb->state = VB2_BUF_STATE_QUEUED; + if (V4L2_TYPE_IS_OUTPUT(q->type)) { + /* + * For output buffers copy the timestamp if needed, + * and the timecode field and flag if needed. + */ + if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY) + vb->v4l2_buf.timestamp = b->timestamp; + vb->v4l2_buf.flags |= b->flags & V4L2_BUF_FLAG_TIMECODE; + if (b->flags & V4L2_BUF_FLAG_TIMECODE) + vb->v4l2_buf.timecode = b->timecode; + } + + /* + * If already streaming, give the buffer to driver for processing. + * If not, the buffer will be given to driver on next streamon. + */ + if (q->start_streaming_called) + __enqueue_in_driver(vb); + + /* Fill buffer information for the userspace */ + __fill_v4l2_buffer(vb, b); + + /* + * If streamon has been called, and we haven't yet called + * start_streaming() since not enough buffers were queued, and + * we now have reached the minimum number of queued buffers, + * then we can finally call start_streaming(). + */ + if (q->streaming && !q->start_streaming_called && + q->queued_count >= q->min_buffers_needed) { + ret = vb2_start_streaming(q); + if (ret) + return ret; + } + + dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index); + return 0; +} + +/** + * vb2_qbuf() - Queue a buffer from userspace + * @q: videobuf2 queue + * @b: buffer structure passed from userspace to vidioc_qbuf handler + * in driver + * + * Should be called from vidioc_qbuf ioctl handler of a driver. + * This function: + * 1) verifies the passed buffer, + * 2) if necessary, calls buf_prepare callback in the driver (if provided), in + * which driver-specific buffer initialization can be performed, + * 3) if streaming is on, queues the buffer in driver by the means of buf_queue + * callback for processing. + * + * The return values from this function are intended to be directly returned + * from vidioc_qbuf handler in driver. + */ +int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + return vb2_internal_qbuf(q, b); +} +EXPORT_SYMBOL_GPL(vb2_qbuf); + +/** + * __vb2_wait_for_done_vb() - wait for a buffer to become available + * for dequeuing + * + * Will sleep if required for nonblocking == false. + */ +static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking) +{ + /* + * All operations on vb_done_list are performed under done_lock + * spinlock protection. However, buffers may be removed from + * it and returned to userspace only while holding both driver's + * lock and the done_lock spinlock. Thus we can be sure that as + * long as we hold the driver's lock, the list will remain not + * empty if list_empty() check succeeds. + */ + + for (;;) { + int ret; + + if (!q->streaming) { + dprintk(1, "streaming off, will not wait for buffers\n"); + return -EINVAL; + } + + if (!list_empty(&q->done_list)) { + /* + * Found a buffer that we were waiting for. + */ + break; + } + + if (nonblocking) { + dprintk(1, "nonblocking and no buffers to dequeue, " + "will not wait\n"); + return -EAGAIN; + } + + /* + * We are streaming and blocking, wait for another buffer to + * become ready or for streamoff. Driver's lock is released to + * allow streamoff or qbuf to be called while waiting. + */ + call_void_qop(q, wait_prepare, q); + + /* + * All locks have been released, it is safe to sleep now. + */ + dprintk(3, "will sleep waiting for buffers\n"); + ret = wait_event_interruptible(q->done_wq, + !list_empty(&q->done_list) || !q->streaming); + + /* + * We need to reevaluate both conditions again after reacquiring + * the locks or return an error if one occurred. + */ + call_void_qop(q, wait_finish, q); + if (ret) { + dprintk(1, "sleep was interrupted\n"); + return ret; + } + } + return 0; +} + +/** + * __vb2_get_done_vb() - get a buffer ready for dequeuing + * + * Will sleep if required for nonblocking == false. + */ +static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb, + struct v4l2_buffer *b, int nonblocking) +{ + unsigned long flags; + int ret; + + /* + * Wait for at least one buffer to become available on the done_list. + */ + ret = __vb2_wait_for_done_vb(q, nonblocking); + if (ret) + return ret; + + /* + * Driver's lock has been held since we last verified that done_list + * is not empty, so no need for another list_empty(done_list) check. + */ + spin_lock_irqsave(&q->done_lock, flags); + *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry); + /* + * Only remove the buffer from done_list if v4l2_buffer can handle all + * the planes. + */ + ret = __verify_planes_array(*vb, b); + if (!ret) + list_del(&(*vb)->done_entry); + spin_unlock_irqrestore(&q->done_lock, flags); + + return ret; +} + +/** + * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2 + * @q: videobuf2 queue + * + * This function will wait until all buffers that have been given to the driver + * by buf_queue() are given back to vb2 with vb2_buffer_done(). It doesn't call + * wait_prepare, wait_finish pair. It is intended to be called with all locks + * taken, for example from stop_streaming() callback. + */ +int vb2_wait_for_all_buffers(struct vb2_queue *q) +{ + if (!q->streaming) { + dprintk(1, "streaming off, will not wait for buffers\n"); + return -EINVAL; + } + + if (q->start_streaming_called) + wait_event(q->done_wq, !atomic_read(&q->owned_by_drv_count)); + return 0; +} +EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers); + +/** + * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state + */ +static void __vb2_dqbuf(struct vb2_buffer *vb) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned int i; + + /* nothing to do if the buffer is already dequeued */ + if (vb->state == VB2_BUF_STATE_DEQUEUED) + return; + + vb->state = VB2_BUF_STATE_DEQUEUED; + + /* unmap DMABUF buffer */ + if (q->memory == V4L2_MEMORY_DMABUF) + for (i = 0; i < vb->num_planes; ++i) { + if (!vb->planes[i].dbuf_mapped) + continue; + call_void_memop(vb, unmap_dmabuf, vb->planes[i].mem_priv); + vb->planes[i].dbuf_mapped = 0; + } +} + +static int vb2_internal_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) +{ + struct vb2_buffer *vb = NULL; + int ret; + + if (b->type != q->type) { + dprintk(1, "invalid buffer type\n"); + return -EINVAL; + } + ret = __vb2_get_done_vb(q, &vb, b, nonblocking); + if (ret < 0) + return ret; + + switch (vb->state) { + case VB2_BUF_STATE_DONE: + dprintk(3, "returning done buffer\n"); + break; + case VB2_BUF_STATE_ERROR: + dprintk(3, "returning done buffer with errors\n"); + break; + default: + dprintk(1, "invalid buffer state\n"); + return -EINVAL; + } + + call_void_vb_qop(vb, buf_finish, vb); + + /* Fill buffer information for the userspace */ + __fill_v4l2_buffer(vb, b); + /* Remove from videobuf queue */ + list_del(&vb->queued_entry); + q->queued_count--; + /* go back to dequeued state */ + __vb2_dqbuf(vb); + + dprintk(1, "dqbuf of buffer %d, with state %d\n", + vb->v4l2_buf.index, vb->state); + + return 0; +} + +/** + * vb2_dqbuf() - Dequeue a buffer to the userspace + * @q: videobuf2 queue + * @b: buffer structure passed from userspace to vidioc_dqbuf handler + * in driver + * @nonblocking: if true, this call will not sleep waiting for a buffer if no + * buffers ready for dequeuing are present. Normally the driver + * would be passing (file->f_flags & O_NONBLOCK) here + * + * Should be called from vidioc_dqbuf ioctl handler of a driver. + * This function: + * 1) verifies the passed buffer, + * 2) calls buf_finish callback in the driver (if provided), in which + * driver can perform any additional operations that may be required before + * returning the buffer to userspace, such as cache sync, + * 3) the buffer struct members are filled with relevant information for + * the userspace. + * + * The return values from this function are intended to be directly returned + * from vidioc_dqbuf handler in driver. + */ +int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_internal_dqbuf(q, b, nonblocking); +} +EXPORT_SYMBOL_GPL(vb2_dqbuf); + +/** + * __vb2_queue_cancel() - cancel and stop (pause) streaming + * + * Removes all queued buffers from driver's queue and all buffers queued by + * userspace from videobuf's queue. Returns to state after reqbufs. + */ +static void __vb2_queue_cancel(struct vb2_queue *q) +{ + unsigned int i; + + /* + * Tell driver to stop all transactions and release all queued + * buffers. + */ + if (q->start_streaming_called) + call_void_qop(q, stop_streaming, q); + + 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) + vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR); + /* Must be zero now */ + WARN_ON(atomic_read(&q->owned_by_drv_count)); + } + + q->streaming = 0; + q->start_streaming_called = 0; + q->queued_count = 0; + + /* + * Remove all buffers from videobuf's list... + */ + INIT_LIST_HEAD(&q->queued_list); + /* + * ...and done list; userspace will not receive any buffers it + * has not already dequeued before initiating cancel. + */ + INIT_LIST_HEAD(&q->done_list); + atomic_set(&q->owned_by_drv_count, 0); + wake_up_all(&q->done_wq); + + /* + * Reinitialize all buffers for next use. + * Make sure to call buf_finish for any queued buffers. Normally + * that's done in dqbuf, but that's not going to happen when we + * cancel the whole queue. Note: this code belongs here, not in + * __vb2_dqbuf() since in vb2_internal_dqbuf() there is a critical + * call to __fill_v4l2_buffer() after buf_finish(). That order can't + * 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]; + + if (vb->state != VB2_BUF_STATE_DEQUEUED) { + vb->state = VB2_BUF_STATE_PREPARED; + call_void_vb_qop(vb, buf_finish, vb); + } + __vb2_dqbuf(vb); + } +} + +static int vb2_internal_streamon(struct vb2_queue *q, enum v4l2_buf_type type) +{ + int ret; + + if (type != q->type) { + dprintk(1, "invalid stream type\n"); + return -EINVAL; + } + + if (q->streaming) { + dprintk(3, "already streaming\n"); + return 0; + } + + if (!q->num_buffers) { + dprintk(1, "no buffers have been allocated\n"); + return -EINVAL; + } + + if (q->num_buffers < q->min_buffers_needed) { + dprintk(1, "need at least %u allocated buffers\n", + q->min_buffers_needed); + return -EINVAL; + } + + /* + * Tell driver to start streaming provided sufficient buffers + * are available. + */ + if (q->queued_count >= q->min_buffers_needed) { + ret = vb2_start_streaming(q); + if (ret) { + __vb2_queue_cancel(q); + return ret; + } + } + + q->streaming = 1; + + dprintk(3, "successful\n"); + return 0; +} + +/** + * vb2_streamon - start streaming + * @q: videobuf2 queue + * @type: type argument passed from userspace to vidioc_streamon handler + * + * Should be called from vidioc_streamon handler of a driver. + * This function: + * 1) verifies current state + * 2) passes any previously queued buffers to the driver and starts streaming + * + * The return values from this function are intended to be directly returned + * from vidioc_streamon handler in the driver. + */ +int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_internal_streamon(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamon); + +static int vb2_internal_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (type != q->type) { + dprintk(1, "invalid stream type\n"); + return -EINVAL; + } + + /* + * Cancel will pause streaming and remove all buffers from the driver + * and videobuf, effectively returning control over them to userspace. + * + * Note that we do this even if q->streaming == 0: if you prepare or + * queue buffers, and then call streamoff without ever having called + * streamon, you would still expect those buffers to be returned to + * their normal dequeued state. + */ + __vb2_queue_cancel(q); + + dprintk(3, "successful\n"); + return 0; +} + +/** + * vb2_streamoff - stop streaming + * @q: videobuf2 queue + * @type: type argument passed from userspace to vidioc_streamoff handler + * + * Should be called from vidioc_streamoff handler of a driver. + * This function: + * 1) verifies current state, + * 2) stop streaming and dequeues any queued buffers, including those previously + * passed to the driver (after waiting for the driver to finish). + * + * This call can be used for pausing playback. + * The return values from this function are intended to be directly returned + * from vidioc_streamoff handler in the driver + */ +int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_internal_streamoff(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamoff); + +/** + * __find_plane_by_offset() - find plane associated with the given offset off + */ +static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off, + unsigned int *_buffer, unsigned int *_plane) +{ + struct vb2_buffer *vb; + unsigned int buffer, plane; + + /* + * Go over all buffers and their planes, comparing the given offset + * with an offset assigned to each plane. If a match is found, + * return its buffer and plane numbers. + */ + for (buffer = 0; buffer < q->num_buffers; ++buffer) { + vb = q->bufs[buffer]; + + for (plane = 0; plane < vb->num_planes; ++plane) { + if (vb->v4l2_planes[plane].m.mem_offset == off) { + *_buffer = buffer; + *_plane = plane; + return 0; + } + } + } + + return -EINVAL; +} + +/** + * vb2_expbuf() - Export a buffer as a file descriptor + * @q: videobuf2 queue + * @eb: export buffer structure passed from userspace to vidioc_expbuf + * handler in driver + * + * The return values from this function are intended to be directly returned + * from vidioc_expbuf handler in driver. + */ +int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) +{ + struct vb2_buffer *vb = NULL; + struct vb2_plane *vb_plane; + int ret; + struct dma_buf *dbuf; + + if (q->memory != V4L2_MEMORY_MMAP) { + dprintk(1, "queue is not currently set up for mmap\n"); + return -EINVAL; + } + + if (!q->mem_ops->get_dmabuf) { + dprintk(1, "queue does not support DMA buffer exporting\n"); + return -EINVAL; + } + + if (eb->flags & ~(O_CLOEXEC | O_ACCMODE)) { + dprintk(1, "queue does support only O_CLOEXEC and access mode flags\n"); + return -EINVAL; + } + + if (eb->type != q->type) { + dprintk(1, "invalid buffer type\n"); + return -EINVAL; + } + + if (eb->index >= q->num_buffers) { + dprintk(1, "buffer index out of range\n"); + return -EINVAL; + } + + vb = q->bufs[eb->index]; + + if (eb->plane >= vb->num_planes) { + dprintk(1, "buffer plane out of range\n"); + return -EINVAL; + } + + if (vb2_fileio_is_active(q)) { + dprintk(1, "expbuf: file io in progress\n"); + return -EBUSY; + } + + vb_plane = &vb->planes[eb->plane]; + + dbuf = call_ptr_memop(vb, get_dmabuf, vb_plane->mem_priv, eb->flags & O_ACCMODE); + if (IS_ERR_OR_NULL(dbuf)) { + dprintk(1, "failed to export buffer %d, plane %d\n", + eb->index, eb->plane); + return -EINVAL; + } + + ret = dma_buf_fd(dbuf, eb->flags & ~O_ACCMODE); + if (ret < 0) { + dprintk(3, "buffer %d, plane %d failed to export (%d)\n", + eb->index, eb->plane, ret); + dma_buf_put(dbuf); + return ret; + } + + dprintk(3, "buffer %d, plane %d exported as %d descriptor\n", + eb->index, eb->plane, ret); + eb->fd = ret; + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_expbuf); + +/** + * vb2_mmap() - map video buffers into application address space + * @q: videobuf2 queue + * @vma: vma passed to the mmap file operation handler in the driver + * + * Should be called from mmap file operation handler of a driver. + * This function maps one plane of one of the available video buffers to + * userspace. To map whole video memory allocated on reqbufs, this function + * has to be called once per each plane per each buffer previously allocated. + * + * When the userspace application calls mmap, it passes to it an offset returned + * to it earlier by the means of vidioc_querybuf handler. That offset acts as + * a "cookie", which is then used to identify the plane to be mapped. + * This function finds a plane with a matching offset and a mapping is performed + * by the means of a provided memory operation. + * + * The return values from this function are intended to be directly returned + * from the mmap handler in driver. + */ +int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma) +{ + unsigned long off = vma->vm_pgoff << PAGE_SHIFT; + struct vb2_buffer *vb; + unsigned int buffer = 0, plane = 0; + int ret; + unsigned long length; + + if (q->memory != V4L2_MEMORY_MMAP) { + dprintk(1, "queue is not currently set up for mmap\n"); + return -EINVAL; + } + + /* + * Check memory area access mode. + */ + if (!(vma->vm_flags & VM_SHARED)) { + dprintk(1, "invalid vma flags, VM_SHARED needed\n"); + return -EINVAL; + } + if (V4L2_TYPE_IS_OUTPUT(q->type)) { + if (!(vma->vm_flags & VM_WRITE)) { + dprintk(1, "invalid vma flags, VM_WRITE needed\n"); + return -EINVAL; + } + } else { + if (!(vma->vm_flags & VM_READ)) { + dprintk(1, "invalid vma flags, VM_READ needed\n"); + return -EINVAL; + } + } + if (vb2_fileio_is_active(q)) { + dprintk(1, "mmap: file io in progress\n"); + return -EBUSY; + } + + /* + * Find the plane corresponding to the offset passed by userspace. + */ + ret = __find_plane_by_offset(q, off, &buffer, &plane); + if (ret) + return ret; + + vb = q->bufs[buffer]; + + /* + * MMAP requires page_aligned buffers. + * The buffer length was page_aligned at __vb2_buf_mem_alloc(), + * so, we need to do the same here. + */ + length = PAGE_ALIGN(vb->v4l2_planes[plane].length); + if (length < (vma->vm_end - vma->vm_start)) { + dprintk(1, + "MMAP invalid, as it would overflow buffer length\n"); + return -EINVAL; + } + + ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma); + if (ret) + return ret; + + dprintk(3, "buffer %d, plane %d successfully mapped\n", buffer, plane); + return 0; +} +EXPORT_SYMBOL_GPL(vb2_mmap); + +#ifndef CONFIG_MMU +unsigned long vb2_get_unmapped_area(struct vb2_queue *q, + unsigned long addr, + unsigned long len, + unsigned long pgoff, + unsigned long flags) +{ + unsigned long off = pgoff << PAGE_SHIFT; + struct vb2_buffer *vb; + unsigned int buffer, plane; + int ret; + + if (q->memory != V4L2_MEMORY_MMAP) { + dprintk(1, "queue is not currently set up for mmap\n"); + return -EINVAL; + } + + /* + * Find the plane corresponding to the offset passed by userspace. + */ + ret = __find_plane_by_offset(q, off, &buffer, &plane); + if (ret) + return ret; + + vb = q->bufs[buffer]; + + return (unsigned long)vb2_plane_vaddr(vb, plane); +} +EXPORT_SYMBOL_GPL(vb2_get_unmapped_area); +#endif + +static int __vb2_init_fileio(struct vb2_queue *q, int read); +static int __vb2_cleanup_fileio(struct vb2_queue *q); + +/** + * vb2_poll() - implements poll userspace operation + * @q: videobuf2 queue + * @file: file argument passed to the poll file operation handler + * @wait: wait argument passed to the poll file operation handler + * + * This function implements poll file operation handler for a driver. + * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will + * be informed that the file descriptor of a video device is available for + * reading. + * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor + * will be reported as available for writing. + * + * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any + * pending events. + * + * The return values from this function are intended to be directly returned + * from poll handler in driver. + */ +unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) +{ + struct video_device *vfd = video_devdata(file); + unsigned long req_events = poll_requested_events(wait); + struct vb2_buffer *vb = NULL; + unsigned int res = 0; + unsigned long flags; + + if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { + struct v4l2_fh *fh = file->private_data; + + if (v4l2_event_pending(fh)) + res = POLLPRI; + else if (req_events & POLLPRI) + poll_wait(file, &fh->wait, wait); + } + + if (!V4L2_TYPE_IS_OUTPUT(q->type) && !(req_events & (POLLIN | POLLRDNORM))) + return res; + if (V4L2_TYPE_IS_OUTPUT(q->type) && !(req_events & (POLLOUT | POLLWRNORM))) + return res; + + /* + * Start file I/O emulator only if streaming API has not been used yet. + */ + if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) { + if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ) && + (req_events & (POLLIN | POLLRDNORM))) { + if (__vb2_init_fileio(q, 1)) + return res | POLLERR; + } + if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE) && + (req_events & (POLLOUT | POLLWRNORM))) { + if (__vb2_init_fileio(q, 0)) + return res | POLLERR; + /* + * Write to OUTPUT queue can be done immediately. + */ + return res | POLLOUT | POLLWRNORM; + } + } + + /* + * There is nothing to wait for if no buffers have already been queued. + */ + if (list_empty(&q->queued_list)) + return res | POLLERR; + + if (list_empty(&q->done_list)) + poll_wait(file, &q->done_wq, wait); + + /* + * Take first buffer available for dequeuing. + */ + spin_lock_irqsave(&q->done_lock, flags); + if (!list_empty(&q->done_list)) + vb = list_first_entry(&q->done_list, struct vb2_buffer, + done_entry); + spin_unlock_irqrestore(&q->done_lock, flags); + + if (vb && (vb->state == VB2_BUF_STATE_DONE + || vb->state == VB2_BUF_STATE_ERROR)) { + return (V4L2_TYPE_IS_OUTPUT(q->type)) ? + res | POLLOUT | POLLWRNORM : + res | POLLIN | POLLRDNORM; + } + return res; +} +EXPORT_SYMBOL_GPL(vb2_poll); + +/** + * vb2_queue_init() - initialize a videobuf2 queue + * @q: videobuf2 queue; this structure should be allocated in driver + * + * The vb2_queue structure should be allocated by the driver. The driver is + * responsible of clearing it's content and setting initial values for some + * required entries before calling this function. + * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer + * to the struct vb2_queue description in include/media/videobuf2-core.h + * for more information. + */ +int vb2_queue_init(struct vb2_queue *q) +{ + /* + * Sanity check + */ + if (WARN_ON(!q) || + WARN_ON(!q->ops) || + WARN_ON(!q->mem_ops) || + WARN_ON(!q->type) || + WARN_ON(!q->io_modes) || + WARN_ON(!q->ops->queue_setup) || + WARN_ON(!q->ops->buf_queue) || + WARN_ON(q->timestamp_flags & + ~(V4L2_BUF_FLAG_TIMESTAMP_MASK | + V4L2_BUF_FLAG_TSTAMP_SRC_MASK))) + return -EINVAL; + + /* Warn that the driver should choose an appropriate timestamp type */ + WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN); + + INIT_LIST_HEAD(&q->queued_list); + INIT_LIST_HEAD(&q->done_list); + spin_lock_init(&q->done_lock); + init_waitqueue_head(&q->done_wq); + + if (q->buf_struct_size == 0) + q->buf_struct_size = sizeof(struct vb2_buffer); + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_queue_init); + +/** + * vb2_queue_release() - stop streaming, release the queue and free memory + * @q: videobuf2 queue + * + * This function stops streaming and performs necessary clean ups, including + * freeing video buffer memory. The driver is responsible for freeing + * the vb2_queue structure itself. + */ +void vb2_queue_release(struct vb2_queue *q) +{ + __vb2_cleanup_fileio(q); + __vb2_queue_cancel(q); + __vb2_queue_free(q, q->num_buffers); +} +EXPORT_SYMBOL_GPL(vb2_queue_release); + +/** + * struct vb2_fileio_buf - buffer context used by file io emulator + * + * vb2 provides a compatibility layer and emulator of file io (read and + * write) calls on top of streaming API. This structure is used for + * tracking context related to the buffers. + */ +struct vb2_fileio_buf { + void *vaddr; + unsigned int size; + unsigned int pos; + unsigned int queued:1; +}; + +/** + * struct vb2_fileio_data - queue context used by file io emulator + * + * @cur_index: the index of the buffer currently being read from or + * written to. If equal to q->num_buffers then a new buffer + * must be dequeued. + * @initial_index: in the read() case all buffers are queued up immediately + * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles + * buffers. However, in the write() case no buffers are initially + * queued, instead whenever a buffer is full it is queued up by + * __vb2_perform_fileio(). Only once all available buffers have + * been queued up will __vb2_perform_fileio() start to dequeue + * buffers. This means that initially __vb2_perform_fileio() + * needs to know what buffer index to use when it is queuing up + * the buffers for the first time. That initial index is stored + * in this field. Once it is equal to q->num_buffers all + * available buffers have been queued and __vb2_perform_fileio() + * should start the normal dequeue/queue cycle. + * + * vb2 provides a compatibility layer and emulator of file io (read and + * write) calls on top of streaming API. For proper operation it required + * this structure to save the driver state between each call of the read + * or write function. + */ +struct vb2_fileio_data { + struct v4l2_requestbuffers req; + struct v4l2_plane p; + struct v4l2_buffer b; + struct vb2_fileio_buf bufs[VIDEO_MAX_FRAME]; + unsigned int cur_index; + unsigned int initial_index; + unsigned int q_count; + unsigned int dq_count; + unsigned int flags; +}; + +/** + * __vb2_init_fileio() - initialize file io emulator + * @q: videobuf2 queue + * @read: mode selector (1 means read, 0 means write) + */ +static int __vb2_init_fileio(struct vb2_queue *q, int read) +{ + struct vb2_fileio_data *fileio; + int i, ret; + unsigned int count = 0; + + /* + * Sanity check + */ + if (WARN_ON((read && !(q->io_modes & VB2_READ)) || + (!read && !(q->io_modes & VB2_WRITE)))) + return -EINVAL; + + /* + * Check if device supports mapping buffers to kernel virtual space. + */ + if (!q->mem_ops->vaddr) + return -EBUSY; + + /* + * Check if streaming api has not been already activated. + */ + if (q->streaming || q->num_buffers > 0) + return -EBUSY; + + /* + * Start with count 1, driver can increase it in queue_setup() + */ + count = 1; + + dprintk(3, "setting up file io: mode %s, count %d, flags %08x\n", + (read) ? "read" : "write", count, q->io_flags); + + fileio = kzalloc(sizeof(struct vb2_fileio_data), GFP_KERNEL); + if (fileio == NULL) + return -ENOMEM; + + fileio->flags = q->io_flags; + + /* + * Request buffers and use MMAP type to force driver + * to allocate buffers by itself. + */ + fileio->req.count = count; + fileio->req.memory = V4L2_MEMORY_MMAP; + fileio->req.type = q->type; + q->fileio = fileio; + ret = __reqbufs(q, &fileio->req); + if (ret) + goto err_kfree; + + /* + * Check if plane_count is correct + * (multiplane buffers are not supported). + */ + if (q->bufs[0]->num_planes != 1) { + ret = -EBUSY; + goto err_reqbufs; + } + + /* + * 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); + if (fileio->bufs[i].vaddr == NULL) { + ret = -EINVAL; + goto err_reqbufs; + } + fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); + } + + /* + * Read mode requires pre queuing of all buffers. + */ + if (read) { + bool is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); + + /* + * Queue all buffers. + */ + for (i = 0; i < q->num_buffers; i++) { + struct v4l2_buffer *b = &fileio->b; + + memset(b, 0, sizeof(*b)); + b->type = q->type; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + b->m.planes = &fileio->p; + b->length = 1; + } + b->memory = q->memory; + b->index = i; + ret = vb2_internal_qbuf(q, b); + if (ret) + goto err_reqbufs; + fileio->bufs[i].queued = 1; + } + /* + * All buffers have been queued, so mark that by setting + * initial_index to q->num_buffers + */ + fileio->initial_index = q->num_buffers; + fileio->cur_index = q->num_buffers; + } + + /* + * Start streaming. + */ + ret = vb2_internal_streamon(q, q->type); + if (ret) + goto err_reqbufs; + + return ret; + +err_reqbufs: + fileio->req.count = 0; + __reqbufs(q, &fileio->req); + +err_kfree: + q->fileio = NULL; + kfree(fileio); + return ret; +} + +/** + * __vb2_cleanup_fileio() - free resourced used by file io emulator + * @q: videobuf2 queue + */ +static int __vb2_cleanup_fileio(struct vb2_queue *q) +{ + struct vb2_fileio_data *fileio = q->fileio; + + if (fileio) { + vb2_internal_streamoff(q, q->type); + q->fileio = NULL; + fileio->req.count = 0; + vb2_reqbufs(q, &fileio->req); + kfree(fileio); + dprintk(3, "file io emulator closed\n"); + } + return 0; +} + +/** + * __vb2_perform_fileio() - perform a single file io (read or write) operation + * @q: videobuf2 queue + * @data: pointed to target userspace buffer + * @count: number of bytes to read or write + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + * @read: access mode selector (1 means read, 0 means write) + */ +static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblock, int read) +{ + struct vb2_fileio_data *fileio; + struct vb2_fileio_buf *buf; + bool is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); + /* + * When using write() to write data to an output video node the vb2 core + * should set timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody + * else is able to provide this information with the write() operation. + */ + bool set_timestamp = !read && + (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY; + int ret, index; + + dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n", + read ? "read" : "write", (long)*ppos, count, + nonblock ? "non" : ""); + + if (!data) + return -EINVAL; + + /* + * Initialize emulator on first call. + */ + if (!vb2_fileio_is_active(q)) { + ret = __vb2_init_fileio(q, read); + dprintk(3, "vb2_init_fileio result: %d\n", ret); + if (ret) + return ret; + } + fileio = q->fileio; + + /* + * Check if we need to dequeue the buffer. + */ + index = fileio->cur_index; + if (index >= q->num_buffers) { + /* + * Call vb2_dqbuf to get buffer back. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + fileio->b.m.planes = &fileio->p; + fileio->b.length = 1; + } + ret = vb2_internal_dqbuf(q, &fileio->b, nonblock); + dprintk(5, "vb2_dqbuf result: %d\n", ret); + if (ret) + return ret; + fileio->dq_count += 1; + + fileio->cur_index = index = fileio->b.index; + buf = &fileio->bufs[index]; + + /* + * 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); + } else { + buf = &fileio->bufs[index]; + } + + /* + * Limit count on last few bytes of the buffer. + */ + if (buf->pos + count > buf->size) { + count = buf->size - buf->pos; + dprintk(5, "reducing read count: %zd\n", count); + } + + /* + * Transfer data to userspace. + */ + dprintk(3, "copying %zd bytes - buffer %d, offset %u\n", + count, index, buf->pos); + if (read) + ret = copy_to_user(data, buf->vaddr + buf->pos, count); + else + ret = copy_from_user(buf->vaddr + buf->pos, data, count); + if (ret) { + dprintk(3, "error copying data\n"); + return -EFAULT; + } + + /* + * Update counters. + */ + buf->pos += count; + *ppos += count; + + /* + * Queue next buffer if required. + */ + if (buf->pos == buf->size || + (!read && (fileio->flags & VB2_FILEIO_WRITE_IMMEDIATELY))) { + /* + * Check if this is the last buffer to read. + */ + if (read && (fileio->flags & VB2_FILEIO_READ_ONCE) && + fileio->dq_count == 1) { + dprintk(3, "read limit reached\n"); + return __vb2_cleanup_fileio(q); + } + + /* + * Call vb2_qbuf and give buffer to the driver. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + fileio->b.index = index; + fileio->b.bytesused = buf->pos; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + fileio->p.bytesused = buf->pos; + fileio->b.m.planes = &fileio->p; + fileio->b.length = 1; + } + if (set_timestamp) + v4l2_get_timestamp(&fileio->b.timestamp); + ret = vb2_internal_qbuf(q, &fileio->b); + dprintk(5, "vb2_dbuf result: %d\n", ret); + if (ret) + return ret; + + /* + * Buffer has been queued, update the status + */ + buf->pos = 0; + buf->queued = 1; + buf->size = vb2_plane_size(q->bufs[index], 0); + fileio->q_count += 1; + /* + * If we are queuing up buffers for the first time, then + * increase initial_index by one. + */ + if (fileio->initial_index < q->num_buffers) + fileio->initial_index++; + /* + * The next buffer to use is either a buffer that's going to be + * queued for the first time (initial_index < q->num_buffers) + * or it is equal to q->num_buffers, meaning that the next + * time we need to dequeue a buffer since we've now queued up + * all the 'first time' buffers. + */ + fileio->cur_index = fileio->initial_index; + } + + /* + * Return proper number of bytes processed. + */ + if (ret == 0) + ret = count; + return ret; +} + +size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblocking) +{ + return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); +} +EXPORT_SYMBOL_GPL(vb2_read); + +size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, + loff_t *ppos, int nonblocking) +{ + return __vb2_perform_fileio(q, (char __user *) data, count, + ppos, nonblocking, 0); +} +EXPORT_SYMBOL_GPL(vb2_write); + +struct vb2_threadio_data { + struct task_struct *thread; + vb2_thread_fnc fnc; + void *priv; + bool stop; +}; + +static int vb2_thread(void *data) +{ + struct vb2_queue *q = data; + struct vb2_threadio_data *threadio = q->threadio; + struct vb2_fileio_data *fileio = q->fileio; + bool set_timestamp = false; + int prequeue = 0; + int index = 0; + int ret = 0; + + if (V4L2_TYPE_IS_OUTPUT(q->type)) { + prequeue = q->num_buffers; + set_timestamp = + (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY; + } + + set_freezable(); + + for (;;) { + struct vb2_buffer *vb; + + /* + * Call vb2_dqbuf to get buffer back. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + if (prequeue) { + fileio->b.index = index++; + prequeue--; + } else { + call_void_qop(q, wait_finish, q); + ret = vb2_internal_dqbuf(q, &fileio->b, 0); + call_void_qop(q, wait_prepare, q); + dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); + } + if (threadio->stop) + break; + if (ret) + break; + try_to_freeze(); + + vb = q->bufs[fileio->b.index]; + if (!(fileio->b.flags & V4L2_BUF_FLAG_ERROR)) + ret = threadio->fnc(vb, threadio->priv); + if (ret) + break; + call_void_qop(q, wait_finish, q); + if (set_timestamp) + v4l2_get_timestamp(&fileio->b.timestamp); + ret = vb2_internal_qbuf(q, &fileio->b); + call_void_qop(q, wait_prepare, q); + if (ret) + break; + } + + /* Hmm, linux becomes *very* unhappy without this ... */ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + } + return 0; +} + +/* + * This function should not be used for anything else but the videobuf2-dvb + * support. If you think you have another good use-case for this, then please + * contact the linux-media mailinglist first. + */ +int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, + const char *thread_name) +{ + struct vb2_threadio_data *threadio; + int ret = 0; + + if (q->threadio) + return -EBUSY; + if (vb2_is_busy(q)) + return -EBUSY; + if (WARN_ON(q->fileio)) + return -EBUSY; + + threadio = kzalloc(sizeof(*threadio), GFP_KERNEL); + if (threadio == NULL) + return -ENOMEM; + threadio->fnc = fnc; + threadio->priv = priv; + + ret = __vb2_init_fileio(q, !V4L2_TYPE_IS_OUTPUT(q->type)); + dprintk(3, "file io: vb2_init_fileio result: %d\n", ret); + if (ret) + goto nomem; + q->threadio = threadio; + threadio->thread = kthread_run(vb2_thread, q, "vb2-%s", thread_name); + if (IS_ERR(threadio->thread)) { + ret = PTR_ERR(threadio->thread); + threadio->thread = NULL; + goto nothread; + } + return 0; + +nothread: + __vb2_cleanup_fileio(q); +nomem: + kfree(threadio); + return ret; +} +EXPORT_SYMBOL_GPL(vb2_thread_start); + +int vb2_thread_stop(struct vb2_queue *q) +{ + struct vb2_threadio_data *threadio = q->threadio; + struct vb2_fileio_data *fileio = q->fileio; + int err; + + if (threadio == NULL) + return 0; + call_void_qop(q, wait_finish, q); + threadio->stop = true; + vb2_internal_streamoff(q, q->type); + call_void_qop(q, wait_prepare, q); + q->fileio = NULL; + fileio->req.count = 0; + vb2_reqbufs(q, &fileio->req); + kfree(fileio); + err = kthread_stop(threadio->thread); + threadio->thread = NULL; + kfree(threadio); + q->fileio = NULL; + q->threadio = NULL; + return err; +} +EXPORT_SYMBOL_GPL(vb2_thread_stop); + +/* + * The following functions are not part of the vb2 core API, but are helper + * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations + * and struct vb2_ops. + * They contain boilerplate code that most if not all drivers have to do + * and so they simplify the driver code. + */ + +/* The queue is busy if there is a owner and you are not that owner. */ +static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file) +{ + return vdev->queue->owner && vdev->queue->owner != file->private_data; +} + +/* vb2 ioctl helpers */ + +int vb2_ioctl_reqbufs(struct file *file, void *priv, + struct v4l2_requestbuffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = __verify_memory_type(vdev->queue, p->memory, p->type); + + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + res = __reqbufs(vdev->queue, p); + /* If count == 0, then the owner has released all buffers and he + is no longer owner of the queue. Otherwise we have a new owner. */ + if (res == 0) + vdev->queue->owner = p->count ? file->private_data : NULL; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs); + +int vb2_ioctl_create_bufs(struct file *file, void *priv, + struct v4l2_create_buffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = __verify_memory_type(vdev->queue, p->memory, p->format.type); + + p->index = vdev->queue->num_buffers; + /* If count == 0, then just check if memory and type are valid. + Any -EBUSY result from __verify_memory_type can be mapped to 0. */ + if (p->count == 0) + return res != -EBUSY ? res : 0; + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + res = __create_bufs(vdev->queue, p); + if (res == 0) + vdev->queue->owner = file->private_data; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs); + +int vb2_ioctl_prepare_buf(struct file *file, void *priv, + struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_prepare_buf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf); + +int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + /* No need to call vb2_queue_is_busy(), anyone can query buffers. */ + return vb2_querybuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf); + +int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_qbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf); + +int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf); + +int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamon(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamon); + +int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamoff(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff); + +int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_expbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf); + +/* v4l2_file_operations helpers */ + +int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err; + + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + err = vb2_mmap(vdev->queue, vma); + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_mmap); + +int _vb2_fop_release(struct file *file, struct mutex *lock) +{ + struct video_device *vdev = video_devdata(file); + + if (file->private_data == vdev->queue->owner) { + if (lock) + mutex_lock(lock); + vb2_queue_release(vdev->queue); + vdev->queue->owner = NULL; + if (lock) + mutex_unlock(lock); + } + return v4l2_fh_release(file); +} +EXPORT_SYMBOL_GPL(_vb2_fop_release); + +int vb2_fop_release(struct file *file) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + + return _vb2_fop_release(file, lock); +} +EXPORT_SYMBOL_GPL(vb2_fop_release); + +ssize_t vb2_fop_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_write(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_write); + +ssize_t vb2_fop_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_read(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_read); + +unsigned int vb2_fop_poll(struct file *file, poll_table *wait) +{ + struct video_device *vdev = video_devdata(file); + struct vb2_queue *q = vdev->queue; + struct mutex *lock = q->lock ? q->lock : vdev->lock; + unsigned long req_events = poll_requested_events(wait); + unsigned res; + void *fileio; + bool must_lock = false; + + /* Try to be smart: only lock if polling might start fileio, + otherwise locking will only introduce unwanted delays. */ + if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) { + if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ) && + (req_events & (POLLIN | POLLRDNORM))) + must_lock = true; + else if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE) && + (req_events & (POLLOUT | POLLWRNORM))) + must_lock = true; + } + + /* If locking is needed, but this helper doesn't know how, then you + shouldn't be using this helper but you should write your own. */ + WARN_ON(must_lock && !lock); + + if (must_lock && lock && mutex_lock_interruptible(lock)) + return POLLERR; + + fileio = q->fileio; + + res = vb2_poll(vdev->queue, file, wait); + + /* If fileio was started, then we have a new queue owner. */ + if (must_lock && !fileio && q->fileio) + q->owner = file->private_data; + if (must_lock && lock) + mutex_unlock(lock); + return res; +} +EXPORT_SYMBOL_GPL(vb2_fop_poll); + +#ifndef CONFIG_MMU +unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int ret; + + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + ret = vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags); + if (lock) + mutex_unlock(lock); + return ret; +} +EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area); +#endif + +/* vb2_ops helpers. Only use if vq->lock is non-NULL. */ + +void vb2_ops_wait_prepare(struct vb2_queue *vq) +{ + mutex_unlock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare); + +void vb2_ops_wait_finish(struct vb2_queue *vq) +{ + mutex_lock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_finish); + +MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); +MODULE_LICENSE("GPL"); |