diff options
Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-core.c')
| -rw-r--r-- | drivers/media/common/videobuf2/videobuf2-core.c | 2681 |
1 files changed, 2681 insertions, 0 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c new file mode 100644 index 000000000..50015a2ea --- /dev/null +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -0,0 +1,2681 @@ +/* + * videobuf2-core.c - video buffer 2 core 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. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#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/videobuf2-core.h> +#include <media/v4l2-mc.h> + +#include <trace/events/vb2.h> + +static int debug; +module_param(debug, int, 0644); + +#define dprintk(level, fmt, arg...) \ + do { \ + if (debug >= level) \ + pr_info("%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)->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)->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 + +#define call_bufop(q, op, args...) \ +({ \ + int ret = 0; \ + if (q && q->buf_ops && q->buf_ops->op) \ + ret = q->buf_ops->op(args); \ + ret; \ +}) + +#define call_void_bufop(q, op, args...) \ +({ \ + if (q && q->buf_ops && q->buf_ops->op) \ + q->buf_ops->op(args); \ +}) + +static void __vb2_queue_cancel(struct vb2_queue *q); +static void __enqueue_in_driver(struct vb2_buffer *vb); + +/* + * __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; + int ret = -ENOMEM; + + /* + * 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(vb->planes[plane].length); + + /* Did it wrap around? */ + if (size < vb->planes[plane].length) + goto free; + + mem_priv = call_ptr_memop(vb, alloc, + q->alloc_devs[plane] ? : q->dev, + q->dma_attrs, size, q->dma_dir, q->gfp_flags); + if (IS_ERR_OR_NULL(mem_priv)) { + if (mem_priv) + ret = PTR_ERR(mem_priv); + goto free; + } + + /* Associate allocator private data with this plane */ + vb->planes[plane].mem_priv = mem_priv; + } + + 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 ret; +} + +/* + * __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->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); + p->mem_priv = NULL; + p->dbuf = NULL; + p->dbuf_mapped = 0; +} + +/* + * __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_offsets() - setup unique offsets ("cookies") for every plane in + * the buffer. + */ +static void __setup_offsets(struct vb2_buffer *vb) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + unsigned long off = 0; + + if (vb->index) { + struct vb2_buffer *prev = q->bufs[vb->index - 1]; + struct vb2_plane *p = &prev->planes[prev->num_planes - 1]; + + off = PAGE_ALIGN(p->m.offset + p->length); + } + + for (plane = 0; plane < vb->num_planes; ++plane) { + vb->planes[plane].m.offset = off; + + dprintk(3, "buffer %d, plane %d offset 0x%08lx\n", + vb->index, plane, off); + + off += vb->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 vb2_memory memory, + unsigned int num_buffers, unsigned int num_planes, + const unsigned plane_sizes[VB2_MAX_PLANES]) +{ + unsigned int buffer, plane; + struct vb2_buffer *vb; + int ret; + + /* Ensure that q->num_buffers+num_buffers is below VB2_MAX_FRAME */ + num_buffers = min_t(unsigned int, num_buffers, + VB2_MAX_FRAME - q->num_buffers); + + 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; + } + + vb->state = VB2_BUF_STATE_DEQUEUED; + vb->vb2_queue = q; + vb->num_planes = num_planes; + vb->index = q->num_buffers + buffer; + vb->type = q->type; + vb->memory = memory; + for (plane = 0; plane < num_planes; ++plane) { + vb->planes[plane].length = plane_sizes[plane]; + vb->planes[plane].min_length = plane_sizes[plane]; + } + q->bufs[vb->index] = vb; + + /* Allocate video buffer memory for the MMAP type */ + if (memory == VB2_MEMORY_MMAP) { + ret = __vb2_buf_mem_alloc(vb); + if (ret) { + dprintk(1, "failed allocating memory for buffer %d\n", + buffer); + q->bufs[vb->index] = NULL; + kfree(vb); + break; + } + __setup_offsets(vb); + /* + * 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); + q->bufs[vb->index] = NULL; + kfree(vb); + break; + } + } + } + + 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 == VB2_MEMORY_MMAP) + __vb2_buf_mem_free(vb); + else if (q->memory == VB2_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("counters for queue %p:%s\n", q, + unbalanced ? " UNBALANCED!" : ""); + pr_info(" setup: %u start_streaming: %u stop_streaming: %u\n", + q->cnt_queue_setup, q->cnt_start_streaming, + q->cnt_stop_streaming); + pr_info(" 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(" counters for queue %p, buffer %d:%s\n", + q, buffer, unbalanced ? " UNBALANCED!" : ""); + pr_info(" 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(" buf_queue: %u buf_done: %u\n", + vb->cnt_buf_queue, vb->cnt_buf_done); + pr_info(" 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(" get_userptr: %u put_userptr: %u\n", + vb->cnt_mem_get_userptr, vb->cnt_mem_put_userptr); + pr_info(" 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(" 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 = VB2_MEMORY_UNKNOWN; + INIT_LIST_HEAD(&q->queued_list); + } + return 0; +} + +bool vb2_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; +} +EXPORT_SYMBOL(vb2_buffer_in_use); + +/* + * __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 (vb2_buffer_in_use(q, q->bufs[buffer])) + return true; + } + return false; +} + +void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb) +{ + call_void_bufop(q, fill_user_buffer, q->bufs[index], pb); +} +EXPORT_SYMBOL_GPL(vb2_core_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; +} + +int vb2_verify_memory_type(struct vb2_queue *q, + enum vb2_memory memory, unsigned int type) +{ + if (memory != VB2_MEMORY_MMAP && memory != VB2_MEMORY_USERPTR && + memory != VB2_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 == VB2_MEMORY_MMAP && __verify_mmap_ops(q)) { + dprintk(1, "MMAP for current setup unsupported\n"); + return -EINVAL; + } + + if (memory == VB2_MEMORY_USERPTR && __verify_userptr_ops(q)) { + dprintk(1, "USERPTR for current setup unsupported\n"); + return -EINVAL; + } + + if (memory == VB2_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; +} +EXPORT_SYMBOL(vb2_verify_memory_type); + +int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, + unsigned int *count) +{ + unsigned int num_buffers, allocated_buffers, num_planes = 0; + unsigned plane_sizes[VB2_MAX_PLANES] = { }; + int ret; + + if (q->streaming) { + dprintk(1, "streaming active\n"); + return -EBUSY; + } + + if (q->waiting_in_dqbuf && *count) { + dprintk(1, "another dup()ped fd is waiting for a buffer\n"); + return -EBUSY; + } + + if (*count == 0 || q->num_buffers != 0 || + (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory)) { + /* + * We already have buffers allocated, so first check if they + * are not in use and can be freed. + */ + mutex_lock(&q->mmap_lock); + if (q->memory == VB2_MEMORY_MMAP && __buffers_in_use(q)) { + mutex_unlock(&q->mmap_lock); + 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); + mutex_unlock(&q->mmap_lock); + if (ret) + return ret; + + /* + * In case of REQBUFS(0) return immediately without calling + * driver's queue_setup() callback and allocating resources. + */ + if (*count == 0) + return 0; + } + + /* + * Make sure the requested values and current defaults are sane. + */ + WARN_ON(q->min_buffers_needed > VB2_MAX_FRAME); + num_buffers = max_t(unsigned int, *count, q->min_buffers_needed); + num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME); + memset(q->alloc_devs, 0, sizeof(q->alloc_devs)); + q->memory = 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, &num_buffers, &num_planes, + plane_sizes, q->alloc_devs); + if (ret) + return ret; + + /* Finally, allocate buffers and video memory */ + allocated_buffers = + __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes); + 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; + /* + * num_planes is set by the previous queue_setup(), but since it + * signals to queue_setup() whether it is called from create_bufs() + * vs reqbufs() we zero it here to signal that queue_setup() is + * called for the reqbufs() case. + */ + num_planes = 0; + + ret = call_qop(q, queue_setup, q, &num_buffers, + &num_planes, plane_sizes, q->alloc_devs); + + if (!ret && allocated_buffers < num_buffers) + ret = -ENOMEM; + + /* + * Either the driver has accepted a smaller number of buffers, + * or .queue_setup() returned an error + */ + } + + mutex_lock(&q->mmap_lock); + 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); + mutex_unlock(&q->mmap_lock); + return ret; + } + mutex_unlock(&q->mmap_lock); + + /* + * Return the number of successfully allocated buffers + * to the userspace. + */ + *count = allocated_buffers; + q->waiting_for_buffers = !q->is_output; + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_reqbufs); + +int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, + unsigned int *count, unsigned requested_planes, + const unsigned requested_sizes[]) +{ + unsigned int num_planes = 0, num_buffers, allocated_buffers; + unsigned plane_sizes[VB2_MAX_PLANES] = { }; + int ret; + + if (q->num_buffers == VB2_MAX_FRAME) { + dprintk(1, "maximum number of buffers already allocated\n"); + return -ENOBUFS; + } + + if (!q->num_buffers) { + if (q->waiting_in_dqbuf && *count) { + dprintk(1, "another dup()ped fd is waiting for a buffer\n"); + return -EBUSY; + } + memset(q->alloc_devs, 0, sizeof(q->alloc_devs)); + q->memory = memory; + q->waiting_for_buffers = !q->is_output; + } else if (q->memory != memory) { + dprintk(1, "memory model mismatch\n"); + return -EINVAL; + } + + num_buffers = min(*count, VB2_MAX_FRAME - q->num_buffers); + + if (requested_planes && requested_sizes) { + num_planes = requested_planes; + memcpy(plane_sizes, requested_sizes, sizeof(plane_sizes)); + } + + /* + * Ask the driver, whether the requested number of buffers, planes per + * buffer and their sizes are acceptable + */ + ret = call_qop(q, queue_setup, q, &num_buffers, + &num_planes, plane_sizes, q->alloc_devs); + if (ret) + return ret; + + /* Finally, allocate buffers and video memory */ + allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers, + num_planes, plane_sizes); + 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, &num_buffers, + &num_planes, plane_sizes, q->alloc_devs); + + if (!ret && allocated_buffers < num_buffers) + ret = -ENOMEM; + + /* + * Either the driver has accepted a smaller number of buffers, + * or .queue_setup() returned an error + */ + } + + mutex_lock(&q->mmap_lock); + 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); + mutex_unlock(&q->mmap_lock); + return -ENOMEM; + } + mutex_unlock(&q->mmap_lock); + + /* + * Return the number of successfully allocated buffers + * to the userspace. + */ + *count = allocated_buffers; + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_create_bufs); + +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); + +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); + +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 (WARN_ON(state != VB2_BUF_STATE_DONE && + state != VB2_BUF_STATE_ERROR && + state != VB2_BUF_STATE_QUEUED && + state != VB2_BUF_STATE_REQUEUEING)) + 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->index, state); + + if (state != VB2_BUF_STATE_QUEUED && + state != VB2_BUF_STATE_REQUEUEING) { + /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_void_memop(vb, finish, vb->planes[plane].mem_priv); + } + + spin_lock_irqsave(&q->done_lock, flags); + if (state == VB2_BUF_STATE_QUEUED || + state == VB2_BUF_STATE_REQUEUEING) { + vb->state = VB2_BUF_STATE_QUEUED; + } else { + /* Add the buffer to the done buffers list */ + list_add_tail(&vb->done_entry, &q->done_list); + vb->state = state; + } + atomic_dec(&q->owned_by_drv_count); + spin_unlock_irqrestore(&q->done_lock, flags); + + trace_vb2_buf_done(q, vb); + + switch (state) { + case VB2_BUF_STATE_QUEUED: + return; + case VB2_BUF_STATE_REQUEUEING: + if (q->start_streaming_called) + __enqueue_in_driver(vb); + return; + default: + /* Inform any processes that may be waiting for buffers */ + wake_up(&q->done_wq); + break; + } +} +EXPORT_SYMBOL_GPL(vb2_buffer_done); + +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); + +/* + * __prepare_mmap() - prepare an MMAP buffer + */ +static int __prepare_mmap(struct vb2_buffer *vb, const void *pb) +{ + int ret = 0; + + if (pb) + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, vb->planes); + return ret ? ret : call_vb_qop(vb, buf_prepare, vb); +} + +/* + * __prepare_userptr() - prepare a USERPTR buffer + */ +static int __prepare_userptr(struct vb2_buffer *vb, const void *pb) +{ + struct vb2_plane planes[VB2_MAX_PLANES]; + struct vb2_queue *q = vb->vb2_queue; + void *mem_priv; + unsigned int plane; + int ret = 0; + bool reacquired = vb->planes[0].mem_priv == NULL; + + memset(planes, 0, sizeof(planes[0]) * vb->num_planes); + /* Copy relevant information provided by the userspace */ + if (pb) { + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, planes); + if (ret) + return ret; + } + + for (plane = 0; plane < vb->num_planes; ++plane) { + /* Skip the plane if already verified */ + if (vb->planes[plane].m.userptr && + vb->planes[plane].m.userptr == planes[plane].m.userptr + && vb->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 < vb->planes[plane].min_length) { + dprintk(1, "provided buffer size %u is less than setup size %u for plane %d\n", + planes[plane].length, + vb->planes[plane].min_length, + 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; + vb->planes[plane].bytesused = 0; + vb->planes[plane].length = 0; + vb->planes[plane].m.userptr = 0; + vb->planes[plane].data_offset = 0; + + /* Acquire each plane's memory */ + mem_priv = call_ptr_memop(vb, get_userptr, + q->alloc_devs[plane] ? : q->dev, + planes[plane].m.userptr, + planes[plane].length, q->dma_dir); + if (IS_ERR(mem_priv)) { + dprintk(1, "failed acquiring userspace memory for plane %d\n", + plane); + ret = PTR_ERR(mem_priv); + 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->planes[plane].bytesused = planes[plane].bytesused; + vb->planes[plane].length = planes[plane].length; + vb->planes[plane].m.userptr = planes[plane].m.userptr; + vb->planes[plane].data_offset = planes[plane].data_offset; + } + + 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->planes[plane].m.userptr = 0; + vb->planes[plane].length = 0; + } + + return ret; +} + +/* + * __prepare_dmabuf() - prepare a DMABUF buffer + */ +static int __prepare_dmabuf(struct vb2_buffer *vb, const void *pb) +{ + struct vb2_plane planes[VB2_MAX_PLANES]; + struct vb2_queue *q = vb->vb2_queue; + void *mem_priv; + unsigned int plane; + int ret = 0; + bool reacquired = vb->planes[0].mem_priv == NULL; + + memset(planes, 0, sizeof(planes[0]) * vb->num_planes); + /* Copy relevant information provided by the userspace */ + if (pb) { + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, + vb, pb, planes); + if (ret) + return ret; + } + + 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 < vb->planes[plane].min_length) { + dprintk(1, "invalid dmabuf length %u for plane %d, minimum length %u\n", + planes[plane].length, plane, + vb->planes[plane].min_length); + dma_buf_put(dbuf); + ret = -EINVAL; + goto err; + } + + /* Skip the plane if already verified */ + if (dbuf == vb->planes[plane].dbuf && + vb->planes[plane].length == planes[plane].length) { + dma_buf_put(dbuf); + continue; + } + + dprintk(3, "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]); + vb->planes[plane].bytesused = 0; + vb->planes[plane].length = 0; + vb->planes[plane].m.fd = 0; + vb->planes[plane].data_offset = 0; + + /* Acquire each plane's memory */ + mem_priv = call_ptr_memop(vb, attach_dmabuf, + q->alloc_devs[plane] ? : q->dev, + dbuf, planes[plane].length, q->dma_dir); + 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; + } + + /* + * This pins the buffer(s) with dma_buf_map_attachment()). It's done + * here instead just before the DMA, while queueing the buffer(s) so + * userspace knows sooner rather than later if the dma-buf map fails. + */ + 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->planes[plane].bytesused = planes[plane].bytesused; + vb->planes[plane].length = planes[plane].length; + vb->planes[plane].m.fd = planes[plane].m.fd; + vb->planes[plane].data_offset = planes[plane].data_offset; + } + + 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; + + vb->state = VB2_BUF_STATE_ACTIVE; + atomic_inc(&q->owned_by_drv_count); + + trace_vb2_buf_queue(q, vb); + + call_void_vb_qop(vb, buf_queue, vb); +} + +static int __buf_prepare(struct vb2_buffer *vb, const void *pb) +{ + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + int ret; + + if (q->error) { + dprintk(1, "fatal error occurred on queue\n"); + return -EIO; + } + + vb->state = VB2_BUF_STATE_PREPARING; + + switch (q->memory) { + case VB2_MEMORY_MMAP: + ret = __prepare_mmap(vb, pb); + break; + case VB2_MEMORY_USERPTR: + ret = __prepare_userptr(vb, pb); + break; + case VB2_MEMORY_DMABUF: + ret = __prepare_dmabuf(vb, pb); + break; + default: + WARN(1, "Invalid queue type\n"); + ret = -EINVAL; + } + + if (ret) { + dprintk(1, "buffer preparation failed: %d\n", ret); + vb->state = VB2_BUF_STATE_DEQUEUED; + return ret; + } + + /* sync buffers */ + for (plane = 0; plane < vb->num_planes; ++plane) + call_void_memop(vb, prepare, vb->planes[plane].mem_priv); + + vb->state = VB2_BUF_STATE_PREPARED; + + return 0; +} + +int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb) +{ + struct vb2_buffer *vb; + int ret; + + vb = q->bufs[index]; + if (vb->state != VB2_BUF_STATE_DEQUEUED) { + dprintk(1, "invalid buffer state %d\n", + vb->state); + return -EINVAL; + } + + ret = __buf_prepare(vb, pb); + if (ret) + return ret; + + /* Fill buffer information for the userspace */ + call_void_bufop(q, fill_user_buffer, vb, pb); + + dprintk(2, "prepare of buffer %d succeeded\n", vb->index); + + return ret; +} +EXPORT_SYMBOL_GPL(vb2_core_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 */ + q->start_streaming_called = 1; + ret = call_qop(q, start_streaming, q, + atomic_read(&q->owned_by_drv_count)); + if (!ret) + return 0; + + q->start_streaming_called = 0; + + dprintk(1, "driver refused to start streaming\n"); + /* + * If you see this warning, then the driver isn't cleaning up properly + * after a failed start_streaming(). See the start_streaming() + * documentation in videobuf2-core.h for more information how buffers + * should be returned to vb2 in start_streaming(). + */ + 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)); + } + /* + * If done_list is not empty, then start_streaming() didn't call + * vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED) but STATE_ERROR or + * STATE_DONE. + */ + WARN_ON(!list_empty(&q->done_list)); + return ret; +} + +int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb) +{ + struct vb2_buffer *vb; + enum vb2_buffer_state orig_state; + int ret; + + if (q->error) { + dprintk(1, "fatal error occurred on queue\n"); + return -EIO; + } + + vb = q->bufs[index]; + + switch (vb->state) { + case VB2_BUF_STATE_DEQUEUED: + ret = __buf_prepare(vb, pb); + 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. + */ + orig_state = vb->state; + list_add_tail(&vb->queued_entry, &q->queued_list); + q->queued_count++; + q->waiting_for_buffers = false; + vb->state = VB2_BUF_STATE_QUEUED; + + if (pb) + call_void_bufop(q, copy_timestamp, vb, pb); + + trace_vb2_qbuf(q, vb); + + /* + * 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 */ + if (pb) + call_void_bufop(q, fill_user_buffer, vb, pb); + + /* + * 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) { + /* + * Since vb2_core_qbuf will return with an error, + * we should return it to state DEQUEUED since + * the error indicates that the buffer wasn't queued. + */ + list_del(&vb->queued_entry); + q->queued_count--; + vb->state = orig_state; + return ret; + } + } + + dprintk(2, "qbuf of buffer %d succeeded\n", vb->index); + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_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->waiting_in_dqbuf) { + dprintk(1, "another dup()ped fd is waiting for a buffer\n"); + return -EBUSY; + } + + if (!q->streaming) { + dprintk(1, "streaming off, will not wait for buffers\n"); + return -EINVAL; + } + + if (q->error) { + dprintk(1, "Queue in error state, will not wait for buffers\n"); + return -EIO; + } + + if (q->last_buffer_dequeued) { + dprintk(3, "last buffer dequeued already, will not wait for buffers\n"); + return -EPIPE; + } + + if (!list_empty(&q->done_list)) { + /* + * Found a buffer that we were waiting for. + */ + break; + } + + if (nonblocking) { + dprintk(3, "nonblocking and no buffers to dequeue, will not wait\n"); + return -EAGAIN; + } + + q->waiting_in_dqbuf = 1; + /* + * 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 || + q->error); + + /* + * 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); + q->waiting_in_dqbuf = 0; + 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, + void *pb, int nonblocking) +{ + unsigned long flags; + int ret = 0; + + /* + * 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 all planes can be + * handled. Some cases such as V4L2 file I/O and DVB have pb + * == NULL; skip the check then as there's nothing to verify. + */ + if (pb) + ret = call_bufop(q, verify_planes_array, *vb, pb); + if (!ret) + list_del(&(*vb)->done_entry); + spin_unlock_irqrestore(&q->done_lock, flags); + + return ret; +} + +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 == VB2_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; + } +} + +int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, + bool nonblocking) +{ + struct vb2_buffer *vb = NULL; + int ret; + + ret = __vb2_get_done_vb(q, &vb, pb, 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); + + if (pindex) + *pindex = vb->index; + + /* Fill buffer information for the userspace */ + if (pb) + call_void_bufop(q, fill_user_buffer, vb, pb); + + /* Remove from videobuf queue */ + list_del(&vb->queued_entry); + q->queued_count--; + + trace_vb2_dqbuf(q, vb); + + /* go back to dequeued state */ + __vb2_dqbuf(vb); + + dprintk(2, "dqbuf of buffer %d, with state %d\n", + vb->index, vb->state); + + return 0; + +} +EXPORT_SYMBOL_GPL(vb2_core_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 you see this warning, then the driver isn't cleaning up properly + * in stop_streaming(). See the stop_streaming() documentation in + * videobuf2-core.h for more information how buffers should be returned + * to vb2 in stop_streaming(). + */ + if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { + for (i = 0; i < q->num_buffers; ++i) + if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) { + pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n", + q->bufs[i]); + vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR); + } + /* 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; + q->error = 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_core_dqbuf() there is a critical + * call to __fill_user_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_PREPARED || + vb->state == VB2_BUF_STATE_QUEUED) { + unsigned int plane; + + for (plane = 0; plane < vb->num_planes; ++plane) + call_void_memop(vb, finish, + vb->planes[plane].mem_priv); + } + + if (vb->state != VB2_BUF_STATE_DEQUEUED) { + vb->state = VB2_BUF_STATE_PREPARED; + call_void_vb_qop(vb, buf_finish, vb); + } + __vb2_dqbuf(vb); + } +} + +int vb2_core_streamon(struct vb2_queue *q, unsigned int 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 = v4l_vb2q_enable_media_source(q); + if (ret) + return ret; + ret = vb2_start_streaming(q); + if (ret) + return ret; + } + + q->streaming = 1; + + dprintk(3, "successful\n"); + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_streamon); + +void vb2_queue_error(struct vb2_queue *q) +{ + q->error = 1; + + wake_up_all(&q->done_wq); +} +EXPORT_SYMBOL_GPL(vb2_queue_error); + +int vb2_core_streamoff(struct vb2_queue *q, unsigned int 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); + q->waiting_for_buffers = !q->is_output; + q->last_buffer_dequeued = false; + + dprintk(3, "successful\n"); + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_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->planes[plane].m.offset == off) { + *_buffer = buffer; + *_plane = plane; + return 0; + } + } + } + + return -EINVAL; +} + +int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, + unsigned int index, unsigned int plane, unsigned int flags) +{ + struct vb2_buffer *vb = NULL; + struct vb2_plane *vb_plane; + int ret; + struct dma_buf *dbuf; + + if (q->memory != VB2_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 (flags & ~(O_CLOEXEC | O_ACCMODE)) { + dprintk(1, "queue does support only O_CLOEXEC and access mode flags\n"); + return -EINVAL; + } + + if (type != q->type) { + dprintk(1, "invalid buffer type\n"); + return -EINVAL; + } + + if (index >= q->num_buffers) { + dprintk(1, "buffer index out of range\n"); + return -EINVAL; + } + + vb = q->bufs[index]; + + if (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[plane]; + + dbuf = call_ptr_memop(vb, get_dmabuf, vb_plane->mem_priv, + flags & O_ACCMODE); + if (IS_ERR_OR_NULL(dbuf)) { + dprintk(1, "failed to export buffer %d, plane %d\n", + index, plane); + return -EINVAL; + } + + ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE); + if (ret < 0) { + dprintk(3, "buffer %d, plane %d failed to export (%d)\n", + index, plane, ret); + dma_buf_put(dbuf); + return ret; + } + + dprintk(3, "buffer %d, plane %d exported as %d descriptor\n", + index, plane, ret); + *fd = ret; + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_expbuf); + +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 != VB2_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 (q->is_output) { + 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; + } + } + + mutex_lock(&q->mmap_lock); + + if (vb2_fileio_is_active(q)) { + dprintk(1, "mmap: file io in progress\n"); + ret = -EBUSY; + goto unlock; + } + + /* + * Find the plane corresponding to the offset passed by userspace. + */ + ret = __find_plane_by_offset(q, off, &buffer, &plane); + if (ret) + goto unlock; + + 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->planes[plane].length); + if (length < (vma->vm_end - vma->vm_start)) { + dprintk(1, + "MMAP invalid, as it would overflow buffer length\n"); + ret = -EINVAL; + goto unlock; + } + + ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma); + +unlock: + mutex_unlock(&q->mmap_lock); + 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; + void *vaddr; + int ret; + + if (q->memory != VB2_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]; + + vaddr = vb2_plane_vaddr(vb, plane); + return vaddr ? (unsigned long)vaddr : -EINVAL; +} +EXPORT_SYMBOL_GPL(vb2_get_unmapped_area); +#endif + +int vb2_core_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)) + return -EINVAL; + + INIT_LIST_HEAD(&q->queued_list); + INIT_LIST_HEAD(&q->done_list); + spin_lock_init(&q->done_lock); + mutex_init(&q->mmap_lock); + init_waitqueue_head(&q->done_wq); + + q->memory = VB2_MEMORY_UNKNOWN; + + if (q->buf_struct_size == 0) + q->buf_struct_size = sizeof(struct vb2_buffer); + + if (q->bidirectional) + q->dma_dir = DMA_BIDIRECTIONAL; + else + q->dma_dir = q->is_output ? DMA_TO_DEVICE : DMA_FROM_DEVICE; + + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_queue_init); + +static int __vb2_init_fileio(struct vb2_queue *q, int read); +static int __vb2_cleanup_fileio(struct vb2_queue *q); +void vb2_core_queue_release(struct vb2_queue *q) +{ + __vb2_cleanup_fileio(q); + __vb2_queue_cancel(q); + mutex_lock(&q->mmap_lock); + __vb2_queue_free(q, q->num_buffers); + mutex_unlock(&q->mmap_lock); +} +EXPORT_SYMBOL_GPL(vb2_core_queue_release); + +__poll_t vb2_core_poll(struct vb2_queue *q, struct file *file, + poll_table *wait) +{ + __poll_t req_events = poll_requested_events(wait); + struct vb2_buffer *vb = NULL; + unsigned long flags; + + if (!q->is_output && !(req_events & (EPOLLIN | EPOLLRDNORM))) + return 0; + if (q->is_output && !(req_events & (EPOLLOUT | EPOLLWRNORM))) + return 0; + + /* + * 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 (!q->is_output && (q->io_modes & VB2_READ) && + (req_events & (EPOLLIN | EPOLLRDNORM))) { + if (__vb2_init_fileio(q, 1)) + return EPOLLERR; + } + if (q->is_output && (q->io_modes & VB2_WRITE) && + (req_events & (EPOLLOUT | EPOLLWRNORM))) { + if (__vb2_init_fileio(q, 0)) + return EPOLLERR; + /* + * Write to OUTPUT queue can be done immediately. + */ + return EPOLLOUT | EPOLLWRNORM; + } + } + + /* + * There is nothing to wait for if the queue isn't streaming, or if the + * error flag is set. + */ + if (!vb2_is_streaming(q) || q->error) + return EPOLLERR; + + /* + * If this quirk is set and QBUF hasn't been called yet then + * return EPOLLERR as well. This only affects capture queues, output + * queues will always initialize waiting_for_buffers to false. + * This quirk is set by V4L2 for backwards compatibility reasons. + */ + if (q->quirk_poll_must_check_waiting_for_buffers && + q->waiting_for_buffers && (req_events & (EPOLLIN | EPOLLRDNORM))) + return EPOLLERR; + + /* + * For output streams you can call write() as long as there are fewer + * buffers queued than there are buffers available. + */ + if (q->is_output && q->fileio && q->queued_count < q->num_buffers) + return EPOLLOUT | EPOLLWRNORM; + + if (list_empty(&q->done_list)) { + /* + * If the last buffer was dequeued from a capture queue, + * return immediately. DQBUF will return -EPIPE. + */ + if (q->last_buffer_dequeued) + return EPOLLIN | EPOLLRDNORM; + + 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 (q->is_output) ? + EPOLLOUT | EPOLLWRNORM : + EPOLLIN | EPOLLRDNORM; + } + return 0; +} +EXPORT_SYMBOL_GPL(vb2_core_poll); + +/* + * 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 { + unsigned int count; + unsigned int type; + unsigned int memory; + struct vb2_fileio_buf bufs[VB2_MAX_FRAME]; + unsigned int cur_index; + unsigned int initial_index; + unsigned int q_count; + unsigned int dq_count; + unsigned read_once:1; + unsigned write_immediately:1; +}; + +/* + * __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, read_once %d, write_immediately %d\n", + (read) ? "read" : "write", count, q->fileio_read_once, + q->fileio_write_immediately); + + fileio = kzalloc(sizeof(*fileio), GFP_KERNEL); + if (fileio == NULL) + return -ENOMEM; + + fileio->read_once = q->fileio_read_once; + fileio->write_immediately = q->fileio_write_immediately; + + /* + * Request buffers and use MMAP type to force driver + * to allocate buffers by itself. + */ + fileio->count = count; + fileio->memory = VB2_MEMORY_MMAP; + fileio->type = q->type; + q->fileio = fileio; + ret = vb2_core_reqbufs(q, fileio->memory, &fileio->count); + 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) { + /* + * Queue all buffers. + */ + for (i = 0; i < q->num_buffers; i++) { + ret = vb2_core_qbuf(q, i, NULL); + 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_core_streamon(q, q->type); + if (ret) + goto err_reqbufs; + + return ret; + +err_reqbufs: + fileio->count = 0; + vb2_core_reqbufs(q, fileio->memory, &fileio->count); + +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_core_streamoff(q, q->type); + q->fileio = NULL; + fileio->count = 0; + vb2_core_reqbufs(q, fileio->memory, &fileio->count); + 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 = q->is_multiplanar; + /* + * When using write() to write data to an output video node the vb2 core + * should copy timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody + * else is able to provide this information with the write() operation. + */ + bool copy_timestamp = !read && q->copy_timestamp; + unsigned index; + int ret; + + dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n", + read ? "read" : "write", (long)*ppos, count, + nonblock ? "non" : ""); + + if (!data) + return -EINVAL; + + if (q->waiting_in_dqbuf) { + dprintk(3, "another dup()ped fd is %s\n", + read ? "reading" : "writing"); + return -EBUSY; + } + + /* + * 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) { + struct vb2_buffer *b; + + /* + * Call vb2_dqbuf to get buffer back. + */ + ret = vb2_core_dqbuf(q, &index, NULL, nonblock); + dprintk(5, "vb2_dqbuf result: %d\n", ret); + if (ret) + return ret; + fileio->dq_count += 1; + + fileio->cur_index = index; + buf = &fileio->bufs[index]; + b = q->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); + /* Compensate for data_offset on read in the multiplanar case. */ + if (is_multiplanar && read && + b->planes[0].data_offset < buf->size) { + buf->pos = b->planes[0].data_offset; + buf->size -= buf->pos; + } + } 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->write_immediately)) { + struct vb2_buffer *b = q->bufs[index]; + + /* + * Check if this is the last buffer to read. + */ + if (read && 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. + */ + b->planes[0].bytesused = buf->pos; + + if (copy_timestamp) + b->timestamp = ktime_get_ns(); + ret = vb2_core_qbuf(q, index, NULL); + 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; + bool copy_timestamp = false; + unsigned prequeue = 0; + unsigned index = 0; + int ret = 0; + + if (q->is_output) { + prequeue = q->num_buffers; + copy_timestamp = q->copy_timestamp; + } + + set_freezable(); + + for (;;) { + struct vb2_buffer *vb; + + /* + * Call vb2_dqbuf to get buffer back. + */ + if (prequeue) { + vb = q->bufs[index++]; + prequeue--; + } else { + call_void_qop(q, wait_finish, q); + if (!threadio->stop) + ret = vb2_core_dqbuf(q, &index, NULL, 0); + call_void_qop(q, wait_prepare, q); + dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); + if (!ret) + vb = q->bufs[index]; + } + if (ret || threadio->stop) + break; + try_to_freeze(); + + if (vb->state != VB2_BUF_STATE_ERROR) + if (threadio->fnc(vb, threadio->priv)) + break; + call_void_qop(q, wait_finish, q); + if (copy_timestamp) + vb->timestamp = ktime_get_ns(); + if (!threadio->stop) + ret = vb2_core_qbuf(q, vb->index, NULL); + call_void_qop(q, wait_prepare, q); + if (ret || threadio->stop) + 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, !q->is_output); + 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; + int err; + + if (threadio == NULL) + return 0; + threadio->stop = true; + /* Wake up all pending sleeps in the thread */ + vb2_queue_error(q); + err = kthread_stop(threadio->thread); + __vb2_cleanup_fileio(q); + threadio->thread = NULL; + kfree(threadio); + q->threadio = NULL; + return err; +} +EXPORT_SYMBOL_GPL(vb2_thread_stop); + +MODULE_DESCRIPTION("Media buffer core framework"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); +MODULE_LICENSE("GPL"); |