summaryrefslogtreecommitdiffstats
path: root/drivers/media/common/videobuf2/videobuf2-core.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/media/common/videobuf2/videobuf2-core.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-core.c')
-rw-r--r--drivers/media/common/videobuf2/videobuf2-core.c3082
1 files changed, 3082 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..92efc4676
--- /dev/null
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -0,0 +1,3082 @@
+/*
+ * 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(q, level, fmt, arg...) \
+ do { \
+ if (debug >= level) \
+ pr_info("[%s] %s: " fmt, (q)->name, __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((vb)->vb2_queue, 2, "call_memop(%d, %s)%s\n", \
+ (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(op, vb, args...) \
+({ \
+ struct vb2_queue *_q = (vb)->vb2_queue; \
+ void *ptr; \
+ \
+ log_memop(vb, op); \
+ ptr = _q->mem_ops->op ? _q->mem_ops->op(vb, 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(q, 2, "call_qop(%s)%s\n", #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((vb)->vb2_queue, 2, "call_vb_qop(%d, %s)%s\n", \
+ (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(op, vb, args...) \
+ ((vb)->vb2_queue->mem_ops->op ? \
+ (vb)->vb2_queue->mem_ops->op(vb, 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);
+
+static const char *vb2_state_name(enum vb2_buffer_state s)
+{
+ static const char * const state_names[] = {
+ [VB2_BUF_STATE_DEQUEUED] = "dequeued",
+ [VB2_BUF_STATE_IN_REQUEST] = "in request",
+ [VB2_BUF_STATE_PREPARING] = "preparing",
+ [VB2_BUF_STATE_QUEUED] = "queued",
+ [VB2_BUF_STATE_ACTIVE] = "active",
+ [VB2_BUF_STATE_DONE] = "done",
+ [VB2_BUF_STATE_ERROR] = "error",
+ };
+
+ if ((unsigned int)(s) < ARRAY_SIZE(state_names))
+ return state_names[s];
+ return "unknown";
+}
+
+/*
+ * __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) {
+ /* Memops alloc requires size to be page aligned. */
+ 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(alloc,
+ vb,
+ q->alloc_devs[plane] ? : q->dev,
+ size);
+ 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(vb->vb2_queue, 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]);
+}
+
+/*
+ * __vb2_buf_mem_prepare() - call ->prepare() on buffer's private memory
+ * to sync caches
+ */
+static void __vb2_buf_mem_prepare(struct vb2_buffer *vb)
+{
+ unsigned int plane;
+
+ if (vb->synced)
+ return;
+
+ vb->synced = 1;
+ for (plane = 0; plane < vb->num_planes; ++plane)
+ call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
+}
+
+/*
+ * __vb2_buf_mem_finish() - call ->finish on buffer's private memory
+ * to sync caches
+ */
+static void __vb2_buf_mem_finish(struct vb2_buffer *vb)
+{
+ unsigned int plane;
+
+ if (!vb->synced)
+ return;
+
+ vb->synced = 0;
+ for (plane = 0; plane < vb->num_planes; ++plane)
+ call_void_memop(vb, finish, vb->planes[plane].mem_priv);
+}
+
+/*
+ * __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(q, 3, "buffer %d, plane %d offset 0x%08lx\n",
+ vb->index, plane, off);
+
+ off += vb->planes[plane].length;
+ off = PAGE_ALIGN(off);
+ }
+}
+
+static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb)
+{
+ /*
+ * DMA exporter should take care of cache syncs, so we can avoid
+ * explicit ->prepare()/->finish() syncs. For other ->memory types
+ * we always need ->prepare() or/and ->finish() cache sync.
+ */
+ if (q->memory == VB2_MEMORY_DMABUF) {
+ vb->skip_cache_sync_on_finish = 1;
+ vb->skip_cache_sync_on_prepare = 1;
+ return;
+ }
+
+ /*
+ * ->finish() cache sync can be avoided when queue direction is
+ * TO_DEVICE.
+ */
+ if (q->dma_dir == DMA_TO_DEVICE)
+ vb->skip_cache_sync_on_finish = 1;
+}
+
+/*
+ * __vb2_queue_alloc() - allocate vb2 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 vb2 buffer structures */
+ vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
+ if (!vb) {
+ dprintk(q, 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;
+ init_buffer_cache_hints(q, vb);
+ for (plane = 0; plane < num_planes; ++plane) {
+ vb->planes[plane].length = plane_sizes[plane];
+ vb->planes[plane].min_length = plane_sizes[plane];
+ }
+ call_void_bufop(q, init_buffer, vb);
+
+ 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(q, 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(q, 1, "buffer %d %p initialization failed\n",
+ buffer, vb);
+ __vb2_buf_mem_free(vb);
+ q->bufs[vb->index] = NULL;
+ kfree(vb);
+ break;
+ }
+ }
+ }
+
+ dprintk(q, 3, "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(q, 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_out_validate: %u buf_queue: %u buf_done: %u buf_request_complete: %u\n",
+ vb->cnt_buf_out_validate, vb->cnt_buf_queue,
+ vb->cnt_buf_done, vb->cnt_buf_request_complete);
+ 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 vb2 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(q, 1, "unsupported memory type\n");
+ return -EINVAL;
+ }
+
+ if (type != q->type) {
+ dprintk(q, 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(q, 1, "MMAP for current setup unsupported\n");
+ return -EINVAL;
+ }
+
+ if (memory == VB2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
+ dprintk(q, 1, "USERPTR for current setup unsupported\n");
+ return -EINVAL;
+ }
+
+ if (memory == VB2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) {
+ dprintk(q, 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(q, 1, "file io in progress\n");
+ return -EBUSY;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(vb2_verify_memory_type);
+
+static void set_queue_coherency(struct vb2_queue *q, bool non_coherent_mem)
+{
+ q->non_coherent_mem = 0;
+
+ if (!vb2_queue_allows_cache_hints(q))
+ return;
+ q->non_coherent_mem = non_coherent_mem;
+}
+
+static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem)
+{
+ if (non_coherent_mem != q->non_coherent_mem) {
+ dprintk(q, 1, "memory coherency model mismatch\n");
+ return false;
+ }
+ return true;
+}
+
+int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
+ unsigned int flags, unsigned int *count)
+{
+ unsigned int num_buffers, allocated_buffers, num_planes = 0;
+ unsigned plane_sizes[VB2_MAX_PLANES] = { };
+ bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
+ unsigned int i;
+ int ret;
+
+ if (q->streaming) {
+ dprintk(q, 1, "streaming active\n");
+ return -EBUSY;
+ }
+
+ if (q->waiting_in_dqbuf && *count) {
+ dprintk(q, 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) ||
+ !verify_coherency_flags(q, non_coherent_mem)) {
+ /*
+ * We already have buffers allocated, so first check if they
+ * are not in use and can be freed.
+ */
+ mutex_lock(&q->mmap_lock);
+ if (debug && q->memory == VB2_MEMORY_MMAP &&
+ __buffers_in_use(q))
+ dprintk(q, 1, "memory in use, orphaning buffers\n");
+
+ /*
+ * Call queue_cancel to clean up any buffers in the
+ * 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));
+ /*
+ * Set this now to ensure that drivers see the correct q->memory value
+ * in the queue_setup op.
+ */
+ mutex_lock(&q->mmap_lock);
+ q->memory = memory;
+ mutex_unlock(&q->mmap_lock);
+ set_queue_coherency(q, non_coherent_mem);
+
+ /*
+ * 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)
+ goto error;
+
+ /* Check that driver has set sane values */
+ if (WARN_ON(!num_planes)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ for (i = 0; i < num_planes; i++)
+ if (WARN_ON(!plane_sizes[i])) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ /* Finally, allocate buffers and video memory */
+ allocated_buffers =
+ __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes);
+ if (allocated_buffers == 0) {
+ dprintk(q, 1, "memory allocation failed\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /*
+ * 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 and it will reset q->memory to
+ * VB2_MEMORY_UNKNOWN.
+ */
+ __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;
+
+error:
+ mutex_lock(&q->mmap_lock);
+ q->memory = VB2_MEMORY_UNKNOWN;
+ mutex_unlock(&q->mmap_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
+
+int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ unsigned int flags, unsigned int *count,
+ unsigned int requested_planes,
+ const unsigned int requested_sizes[])
+{
+ unsigned int num_planes = 0, num_buffers, allocated_buffers;
+ unsigned plane_sizes[VB2_MAX_PLANES] = { };
+ bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
+ bool no_previous_buffers = !q->num_buffers;
+ int ret;
+
+ if (q->num_buffers == VB2_MAX_FRAME) {
+ dprintk(q, 1, "maximum number of buffers already allocated\n");
+ return -ENOBUFS;
+ }
+
+ if (no_previous_buffers) {
+ if (q->waiting_in_dqbuf && *count) {
+ dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
+ return -EBUSY;
+ }
+ memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
+ /*
+ * Set this now to ensure that drivers see the correct q->memory
+ * value in the queue_setup op.
+ */
+ mutex_lock(&q->mmap_lock);
+ q->memory = memory;
+ mutex_unlock(&q->mmap_lock);
+ q->waiting_for_buffers = !q->is_output;
+ set_queue_coherency(q, non_coherent_mem);
+ } else {
+ if (q->memory != memory) {
+ dprintk(q, 1, "memory model mismatch\n");
+ return -EINVAL;
+ }
+ if (!verify_coherency_flags(q, non_coherent_mem))
+ 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)
+ goto error;
+
+ /* Finally, allocate buffers and video memory */
+ allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers,
+ num_planes, plane_sizes);
+ if (allocated_buffers == 0) {
+ dprintk(q, 1, "memory allocation failed\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /*
+ * 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 and it will reset q->memory to
+ * VB2_MEMORY_UNKNOWN.
+ */
+ __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;
+
+error:
+ if (no_previous_buffers) {
+ mutex_lock(&q->mmap_lock);
+ q->memory = VB2_MEMORY_UNKNOWN;
+ mutex_unlock(&q->mmap_lock);
+ }
+ return ret;
+}
+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(vaddr, vb, 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(cookie, vb, 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;
+
+ 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_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(q, 4, "done processing on buffer %d, state: %s\n",
+ vb->index, vb2_state_name(state));
+
+ if (state != VB2_BUF_STATE_QUEUED)
+ __vb2_buf_mem_finish(vb);
+
+ spin_lock_irqsave(&q->done_lock, flags);
+ if (state == VB2_BUF_STATE_QUEUED) {
+ 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);
+
+ if (state != VB2_BUF_STATE_QUEUED && vb->req_obj.req) {
+ media_request_object_unbind(&vb->req_obj);
+ media_request_object_put(&vb->req_obj);
+ }
+
+ spin_unlock_irqrestore(&q->done_lock, flags);
+
+ trace_vb2_buf_done(q, vb);
+
+ switch (state) {
+ case VB2_BUF_STATE_QUEUED:
+ 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)
+{
+ int ret = 0;
+
+ ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
+ vb, 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)
+{
+ 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 */
+ ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
+ vb, 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(q, 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(q, 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;
+ vb->copied_timestamp = 0;
+ 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(get_userptr,
+ vb,
+ q->alloc_devs[plane] ? : q->dev,
+ planes[plane].m.userptr,
+ planes[plane].length);
+ if (IS_ERR(mem_priv)) {
+ dprintk(q, 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(q, 1, "buffer initialization failed\n");
+ goto err;
+ }
+ }
+
+ ret = call_vb_qop(vb, buf_prepare, vb);
+ if (ret) {
+ dprintk(q, 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)
+{
+ 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 */
+ ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
+ vb, 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(q, 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(q, 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(q, 3, "buffer for plane %d changed\n", plane);
+
+ if (!reacquired) {
+ reacquired = true;
+ vb->copied_timestamp = 0;
+ 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(attach_dmabuf,
+ vb,
+ q->alloc_devs[plane] ? : q->dev,
+ dbuf,
+ planes[plane].length);
+ if (IS_ERR(mem_priv)) {
+ dprintk(q, 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) {
+ if (vb->planes[plane].dbuf_mapped)
+ continue;
+
+ ret = call_memop(vb, map_dmabuf, vb->planes[plane].mem_priv);
+ if (ret) {
+ dprintk(q, 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(q, 1, "buffer initialization failed\n");
+ goto err;
+ }
+ }
+
+ ret = call_vb_qop(vb, buf_prepare, vb);
+ if (ret) {
+ dprintk(q, 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)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ enum vb2_buffer_state orig_state = vb->state;
+ int ret;
+
+ if (q->error) {
+ dprintk(q, 1, "fatal error occurred on queue\n");
+ return -EIO;
+ }
+
+ if (vb->prepared)
+ return 0;
+ WARN_ON(vb->synced);
+
+ if (q->is_output) {
+ ret = call_vb_qop(vb, buf_out_validate, vb);
+ if (ret) {
+ dprintk(q, 1, "buffer validation failed\n");
+ return ret;
+ }
+ }
+
+ vb->state = VB2_BUF_STATE_PREPARING;
+
+ switch (q->memory) {
+ case VB2_MEMORY_MMAP:
+ ret = __prepare_mmap(vb);
+ break;
+ case VB2_MEMORY_USERPTR:
+ ret = __prepare_userptr(vb);
+ break;
+ case VB2_MEMORY_DMABUF:
+ ret = __prepare_dmabuf(vb);
+ break;
+ default:
+ WARN(1, "Invalid queue type\n");
+ ret = -EINVAL;
+ break;
+ }
+
+ if (ret) {
+ dprintk(q, 1, "buffer preparation failed: %d\n", ret);
+ vb->state = orig_state;
+ return ret;
+ }
+
+ __vb2_buf_mem_prepare(vb);
+ vb->prepared = 1;
+ vb->state = orig_state;
+
+ return 0;
+}
+
+static int vb2_req_prepare(struct media_request_object *obj)
+{
+ struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
+ int ret;
+
+ if (WARN_ON(vb->state != VB2_BUF_STATE_IN_REQUEST))
+ return -EINVAL;
+
+ mutex_lock(vb->vb2_queue->lock);
+ ret = __buf_prepare(vb);
+ mutex_unlock(vb->vb2_queue->lock);
+ return ret;
+}
+
+static void __vb2_dqbuf(struct vb2_buffer *vb);
+
+static void vb2_req_unprepare(struct media_request_object *obj)
+{
+ struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
+
+ mutex_lock(vb->vb2_queue->lock);
+ __vb2_dqbuf(vb);
+ vb->state = VB2_BUF_STATE_IN_REQUEST;
+ mutex_unlock(vb->vb2_queue->lock);
+ WARN_ON(!vb->req_obj.req);
+}
+
+int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
+ struct media_request *req);
+
+static void vb2_req_queue(struct media_request_object *obj)
+{
+ struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
+ int err;
+
+ mutex_lock(vb->vb2_queue->lock);
+ /*
+ * There is no method to propagate an error from vb2_core_qbuf(),
+ * so if this returns a non-0 value, then WARN.
+ *
+ * The only exception is -EIO which is returned if q->error is
+ * set. We just ignore that, and expect this will be caught the
+ * next time vb2_req_prepare() is called.
+ */
+ err = vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL);
+ WARN_ON_ONCE(err && err != -EIO);
+ mutex_unlock(vb->vb2_queue->lock);
+}
+
+static void vb2_req_unbind(struct media_request_object *obj)
+{
+ struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
+
+ if (vb->state == VB2_BUF_STATE_IN_REQUEST)
+ call_void_bufop(vb->vb2_queue, init_buffer, vb);
+}
+
+static void vb2_req_release(struct media_request_object *obj)
+{
+ struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
+
+ if (vb->state == VB2_BUF_STATE_IN_REQUEST) {
+ vb->state = VB2_BUF_STATE_DEQUEUED;
+ if (vb->request)
+ media_request_put(vb->request);
+ vb->request = NULL;
+ }
+}
+
+static const struct media_request_object_ops vb2_core_req_ops = {
+ .prepare = vb2_req_prepare,
+ .unprepare = vb2_req_unprepare,
+ .queue = vb2_req_queue,
+ .unbind = vb2_req_unbind,
+ .release = vb2_req_release,
+};
+
+bool vb2_request_object_is_buffer(struct media_request_object *obj)
+{
+ return obj->ops == &vb2_core_req_ops;
+}
+EXPORT_SYMBOL_GPL(vb2_request_object_is_buffer);
+
+unsigned int vb2_request_buffer_cnt(struct media_request *req)
+{
+ struct media_request_object *obj;
+ unsigned long flags;
+ unsigned int buffer_cnt = 0;
+
+ spin_lock_irqsave(&req->lock, flags);
+ list_for_each_entry(obj, &req->objects, list)
+ if (vb2_request_object_is_buffer(obj))
+ buffer_cnt++;
+ spin_unlock_irqrestore(&req->lock, flags);
+
+ return buffer_cnt;
+}
+EXPORT_SYMBOL_GPL(vb2_request_buffer_cnt);
+
+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(q, 1, "invalid buffer state %s\n",
+ vb2_state_name(vb->state));
+ return -EINVAL;
+ }
+ if (vb->prepared) {
+ dprintk(q, 1, "buffer already prepared\n");
+ return -EINVAL;
+ }
+
+ ret = __buf_prepare(vb);
+ if (ret)
+ return ret;
+
+ /* Fill buffer information for the userspace */
+ call_void_bufop(q, fill_user_buffer, vb, pb);
+
+ dprintk(q, 2, "prepare of buffer %d succeeded\n", vb->index);
+
+ return 0;
+}
+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(q, 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 media_request *req)
+{
+ struct vb2_buffer *vb;
+ enum vb2_buffer_state orig_state;
+ int ret;
+
+ if (q->error) {
+ dprintk(q, 1, "fatal error occurred on queue\n");
+ return -EIO;
+ }
+
+ vb = q->bufs[index];
+
+ if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
+ q->requires_requests) {
+ dprintk(q, 1, "qbuf requires a request\n");
+ return -EBADR;
+ }
+
+ if ((req && q->uses_qbuf) ||
+ (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
+ q->uses_requests)) {
+ dprintk(q, 1, "queue in wrong mode (qbuf vs requests)\n");
+ return -EBUSY;
+ }
+
+ if (req) {
+ int ret;
+
+ q->uses_requests = 1;
+ if (vb->state != VB2_BUF_STATE_DEQUEUED) {
+ dprintk(q, 1, "buffer %d not in dequeued state\n",
+ vb->index);
+ return -EINVAL;
+ }
+
+ if (q->is_output && !vb->prepared) {
+ ret = call_vb_qop(vb, buf_out_validate, vb);
+ if (ret) {
+ dprintk(q, 1, "buffer validation failed\n");
+ return ret;
+ }
+ }
+
+ media_request_object_init(&vb->req_obj);
+
+ /* Make sure the request is in a safe state for updating. */
+ ret = media_request_lock_for_update(req);
+ if (ret)
+ return ret;
+ ret = media_request_object_bind(req, &vb2_core_req_ops,
+ q, true, &vb->req_obj);
+ media_request_unlock_for_update(req);
+ if (ret)
+ return ret;
+
+ vb->state = VB2_BUF_STATE_IN_REQUEST;
+
+ /*
+ * Increment the refcount and store the request.
+ * The request refcount is decremented again when the
+ * buffer is dequeued. This is to prevent vb2_buffer_done()
+ * from freeing the request from interrupt context, which can
+ * happen if the application closed the request fd after
+ * queueing the request.
+ */
+ media_request_get(req);
+ vb->request = req;
+
+ /* Fill buffer information for the userspace */
+ if (pb) {
+ call_void_bufop(q, copy_timestamp, vb, pb);
+ call_void_bufop(q, fill_user_buffer, vb, pb);
+ }
+
+ dprintk(q, 2, "qbuf of buffer %d succeeded\n", vb->index);
+ return 0;
+ }
+
+ if (vb->state != VB2_BUF_STATE_IN_REQUEST)
+ q->uses_qbuf = 1;
+
+ switch (vb->state) {
+ case VB2_BUF_STATE_DEQUEUED:
+ case VB2_BUF_STATE_IN_REQUEST:
+ if (!vb->prepared) {
+ ret = __buf_prepare(vb);
+ if (ret)
+ return ret;
+ }
+ break;
+ case VB2_BUF_STATE_PREPARING:
+ dprintk(q, 1, "buffer still being prepared\n");
+ return -EINVAL;
+ default:
+ dprintk(q, 1, "invalid buffer state %s\n",
+ vb2_state_name(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(q, 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(q, 1, "another dup()ped fd is waiting for a buffer\n");
+ return -EBUSY;
+ }
+
+ if (!q->streaming) {
+ dprintk(q, 1, "streaming off, will not wait for buffers\n");
+ return -EINVAL;
+ }
+
+ if (q->error) {
+ dprintk(q, 1, "Queue in error state, will not wait for buffers\n");
+ return -EIO;
+ }
+
+ if (q->last_buffer_dequeued) {
+ dprintk(q, 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(q, 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(q, 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(q, 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(q, 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;
+
+ /* nothing to do if the buffer is already dequeued */
+ if (vb->state == VB2_BUF_STATE_DEQUEUED)
+ return;
+
+ vb->state = VB2_BUF_STATE_DEQUEUED;
+
+ call_void_bufop(q, init_buffer, vb);
+}
+
+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(q, 3, "returning done buffer\n");
+ break;
+ case VB2_BUF_STATE_ERROR:
+ dprintk(q, 3, "returning done buffer with errors\n");
+ break;
+ default:
+ dprintk(q, 1, "invalid buffer state %s\n",
+ vb2_state_name(vb->state));
+ return -EINVAL;
+ }
+
+ call_void_vb_qop(vb, buf_finish, vb);
+ vb->prepared = 0;
+
+ if (pindex)
+ *pindex = vb->index;
+
+ /* Fill buffer information for the userspace */
+ if (pb)
+ call_void_bufop(q, fill_user_buffer, vb, pb);
+
+ /* Remove from vb2 queue */
+ list_del(&vb->queued_entry);
+ q->queued_count--;
+
+ trace_vb2_dqbuf(q, vb);
+
+ /* go back to dequeued state */
+ __vb2_dqbuf(vb);
+
+ if (WARN_ON(vb->req_obj.req)) {
+ media_request_object_unbind(&vb->req_obj);
+ media_request_object_put(&vb->req_obj);
+ }
+ if (vb->request)
+ media_request_put(vb->request);
+ vb->request = NULL;
+
+ dprintk(q, 2, "dqbuf of buffer %d, state: %s\n",
+ vb->index, vb2_state_name(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 vb2'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;
+ q->uses_requests = 0;
+ q->uses_qbuf = 0;
+
+ /*
+ * Remove all buffers from vb2'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];
+ struct media_request *req = vb->req_obj.req;
+
+ /*
+ * If a request is associated with this buffer, then
+ * call buf_request_cancel() to give the driver to complete()
+ * related request objects. Otherwise those objects would
+ * never complete.
+ */
+ if (req) {
+ enum media_request_state state;
+ unsigned long flags;
+
+ spin_lock_irqsave(&req->lock, flags);
+ state = req->state;
+ spin_unlock_irqrestore(&req->lock, flags);
+
+ if (state == MEDIA_REQUEST_STATE_QUEUED)
+ call_void_vb_qop(vb, buf_request_complete, vb);
+ }
+
+ __vb2_buf_mem_finish(vb);
+
+ if (vb->prepared) {
+ call_void_vb_qop(vb, buf_finish, vb);
+ vb->prepared = 0;
+ }
+ __vb2_dqbuf(vb);
+
+ if (vb->req_obj.req) {
+ media_request_object_unbind(&vb->req_obj);
+ media_request_object_put(&vb->req_obj);
+ }
+ if (vb->request)
+ media_request_put(vb->request);
+ vb->request = NULL;
+ vb->copied_timestamp = 0;
+ }
+}
+
+int vb2_core_streamon(struct vb2_queue *q, unsigned int type)
+{
+ int ret;
+
+ if (type != q->type) {
+ dprintk(q, 1, "invalid stream type\n");
+ return -EINVAL;
+ }
+
+ if (q->streaming) {
+ dprintk(q, 3, "already streaming\n");
+ return 0;
+ }
+
+ if (!q->num_buffers) {
+ dprintk(q, 1, "no buffers have been allocated\n");
+ return -EINVAL;
+ }
+
+ if (q->num_buffers < q->min_buffers_needed) {
+ dprintk(q, 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(q, 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(q, 1, "invalid stream type\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Cancel will pause streaming and remove all buffers from the driver
+ * and vb2, 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(q, 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;
+
+ /*
+ * Sanity checks to ensure the lock is held, MEMORY_MMAP is
+ * used and fileio isn't active.
+ */
+ lockdep_assert_held(&q->mmap_lock);
+
+ if (q->memory != VB2_MEMORY_MMAP) {
+ dprintk(q, 1, "queue is not currently set up for mmap\n");
+ return -EINVAL;
+ }
+
+ if (vb2_fileio_is_active(q)) {
+ dprintk(q, 1, "file io in progress\n");
+ return -EBUSY;
+ }
+
+ /*
+ * 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(q, 1, "queue is not currently set up for mmap\n");
+ return -EINVAL;
+ }
+
+ if (!q->mem_ops->get_dmabuf) {
+ dprintk(q, 1, "queue does not support DMA buffer exporting\n");
+ return -EINVAL;
+ }
+
+ if (flags & ~(O_CLOEXEC | O_ACCMODE)) {
+ dprintk(q, 1, "queue does support only O_CLOEXEC and access mode flags\n");
+ return -EINVAL;
+ }
+
+ if (type != q->type) {
+ dprintk(q, 1, "invalid buffer type\n");
+ return -EINVAL;
+ }
+
+ if (index >= q->num_buffers) {
+ dprintk(q, 1, "buffer index out of range\n");
+ return -EINVAL;
+ }
+
+ vb = q->bufs[index];
+
+ if (plane >= vb->num_planes) {
+ dprintk(q, 1, "buffer plane out of range\n");
+ return -EINVAL;
+ }
+
+ if (vb2_fileio_is_active(q)) {
+ dprintk(q, 1, "expbuf: file io in progress\n");
+ return -EBUSY;
+ }
+
+ vb_plane = &vb->planes[plane];
+
+ dbuf = call_ptr_memop(get_dmabuf,
+ vb,
+ vb_plane->mem_priv,
+ flags & O_ACCMODE);
+ if (IS_ERR_OR_NULL(dbuf)) {
+ dprintk(q, 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(q, 3, "buffer %d, plane %d failed to export (%d)\n",
+ index, plane, ret);
+ dma_buf_put(dbuf);
+ return ret;
+ }
+
+ dprintk(q, 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;
+
+ /*
+ * Check memory area access mode.
+ */
+ if (!(vma->vm_flags & VM_SHARED)) {
+ dprintk(q, 1, "invalid vma flags, VM_SHARED needed\n");
+ return -EINVAL;
+ }
+ if (q->is_output) {
+ if (!(vma->vm_flags & VM_WRITE)) {
+ dprintk(q, 1, "invalid vma flags, VM_WRITE needed\n");
+ return -EINVAL;
+ }
+ } else {
+ if (!(vma->vm_flags & VM_READ)) {
+ dprintk(q, 1, "invalid vma flags, VM_READ needed\n");
+ return -EINVAL;
+ }
+ }
+
+ mutex_lock(&q->mmap_lock);
+
+ /*
+ * Find the plane corresponding to the offset passed by userspace. This
+ * will return an error if not MEMORY_MMAP or file I/O is in progress.
+ */
+ 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(q, 1,
+ "MMAP invalid, as it would overflow buffer length\n");
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ /*
+ * vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer,
+ * not as a in-buffer offset. We always want to mmap a whole buffer
+ * from its beginning.
+ */
+ vma->vm_pgoff = 0;
+
+ ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);
+
+unlock:
+ mutex_unlock(&q->mmap_lock);
+ if (ret)
+ return ret;
+
+ dprintk(q, 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;
+
+ mutex_lock(&q->mmap_lock);
+
+ /*
+ * Find the plane corresponding to the offset passed by userspace. This
+ * will return an error if not MEMORY_MMAP or file I/O is in progress.
+ */
+ ret = __find_plane_by_offset(q, off, &buffer, &plane);
+ if (ret)
+ goto unlock;
+
+ vb = q->bufs[buffer];
+
+ vaddr = vb2_plane_vaddr(vb, plane);
+ mutex_unlock(&q->mmap_lock);
+ return vaddr ? (unsigned long)vaddr : -EINVAL;
+
+unlock:
+ mutex_unlock(&q->mmap_lock);
+ return ret;
+}
+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;
+
+ if (WARN_ON(q->requires_requests && !q->supports_requests))
+ return -EINVAL;
+
+ /*
+ * This combination is not allowed since a non-zero value of
+ * q->min_buffers_needed can cause vb2_core_qbuf() to fail if
+ * it has to call start_streaming(), and the Request API expects
+ * that queueing a request (and thus queueing a buffer contained
+ * in that request) will always succeed. There is no method of
+ * propagating an error back to userspace.
+ */
+ if (WARN_ON(q->supports_requests && q->min_buffers_needed))
+ 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;
+
+ if (q->name[0] == '\0')
+ snprintf(q->name, sizeof(q->name), "%s-%p",
+ q->is_output ? "out" : "cap", q);
+
+ 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;
+
+ /*
+ * poll_wait() MUST be called on the first invocation on all the
+ * potential queues of interest, even if we are not interested in their
+ * events during this first call. Failure to do so will result in
+ * queue's events to be ignored because the poll_table won't be capable
+ * of adding new wait queues thereafter.
+ */
+ poll_wait(file, &q->done_wq, wait);
+
+ 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;
+ }
+
+ /*
+ * 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(q, 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, 0, &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, 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, 0, &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, 0, &fileio->count);
+ kfree(fileio);
+ dprintk(q, 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(q, 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(q, 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(q, 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(q, 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(q, 5, "reducing read count: %zd\n", count);
+ }
+
+ /*
+ * Transfer data to userspace.
+ */
+ dprintk(q, 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(q, 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(q, 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, NULL);
+ dprintk(q, 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(q, 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, 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(q, 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");
+MODULE_IMPORT_NS(DMA_BUF);