diff options
Diffstat (limited to 'drivers/media/video/video-buf.c')
| -rw-r--r-- | drivers/media/video/video-buf.c | 1290 |
1 files changed, 1290 insertions, 0 deletions
diff --git a/drivers/media/video/video-buf.c b/drivers/media/video/video-buf.c new file mode 100644 index 000000000000..5afdc7852610 --- /dev/null +++ b/drivers/media/video/video-buf.c @@ -0,0 +1,1290 @@ +/* + * $Id: video-buf.c,v 1.18 2005/02/24 13:32:30 kraxel Exp $ + * + * generic helper functions for video4linux capture buffers, to handle + * memory management and PCI DMA. Right now bttv + saa7134 use it. + * + * The functions expect the hardware being able to scatter gatter + * (i.e. the buffers are not linear in physical memory, but fragmented + * into PAGE_SIZE chunks). They also assume the driver does not need + * to touch the video data (thus it is probably not useful for USB 1.1 + * as data often must be uncompressed by the drivers). + * + * (c) 2001-2004 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; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/vmalloc.h> +#include <linux/pagemap.h> +#include <linux/slab.h> +#include <linux/pci.h> +#include <linux/interrupt.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +#include <media/video-buf.h> + +#define MAGIC_DMABUF 0x19721112 +#define MAGIC_BUFFER 0x20040302 +#define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \ + { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); } + +static int debug = 0; +module_param(debug, int, 0644); + +MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers"); +MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]"); +MODULE_LICENSE("GPL"); + +#define dprintk(level, fmt, arg...) if (debug >= level) \ + printk(KERN_DEBUG "vbuf: " fmt , ## arg) + +struct scatterlist* +videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages) +{ + struct scatterlist *sglist; + struct page *pg; + int i; + + sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL); + if (NULL == sglist) + return NULL; + memset(sglist,0,sizeof(struct scatterlist)*nr_pages); + for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) { + pg = vmalloc_to_page(virt); + if (NULL == pg) + goto err; + if (PageHighMem(pg)) + BUG(); + sglist[i].page = pg; + sglist[i].length = PAGE_SIZE; + } + return sglist; + + err: + kfree(sglist); + return NULL; +} + +struct scatterlist* +videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset) +{ + struct scatterlist *sglist; + int i = 0; + + if (NULL == pages[0]) + return NULL; + sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL); + if (NULL == sglist) + return NULL; + memset(sglist, 0, sizeof(*sglist) * nr_pages); + + if (NULL == pages[0]) + goto nopage; + if (PageHighMem(pages[0])) + /* DMA to highmem pages might not work */ + goto highmem; + sglist[0].page = pages[0]; + sglist[0].offset = offset; + sglist[0].length = PAGE_SIZE - offset; + for (i = 1; i < nr_pages; i++) { + if (NULL == pages[i]) + goto nopage; + if (PageHighMem(pages[i])) + goto highmem; + sglist[i].page = pages[i]; + sglist[i].length = PAGE_SIZE; + } + return sglist; + + nopage: + dprintk(2,"sgl: oops - no page\n"); + kfree(sglist); + return NULL; + + highmem: + dprintk(2,"sgl: oops - highmem page\n"); + kfree(sglist); + return NULL; +} + +/* --------------------------------------------------------------------- */ + +void videobuf_dma_init(struct videobuf_dmabuf *dma) +{ + memset(dma,0,sizeof(*dma)); + dma->magic = MAGIC_DMABUF; +} + +int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction, + unsigned long data, unsigned long size) +{ + unsigned long first,last; + int err, rw = 0; + + dma->direction = direction; + switch (dma->direction) { + case PCI_DMA_FROMDEVICE: rw = READ; break; + case PCI_DMA_TODEVICE: rw = WRITE; break; + default: BUG(); + } + + first = (data & PAGE_MASK) >> PAGE_SHIFT; + last = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT; + dma->offset = data & ~PAGE_MASK; + dma->nr_pages = last-first+1; + dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*), + GFP_KERNEL); + if (NULL == dma->pages) + return -ENOMEM; + dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n", + data,size,dma->nr_pages); + + down_read(¤t->mm->mmap_sem); + err = get_user_pages(current,current->mm, + data & PAGE_MASK, dma->nr_pages, + rw == READ, 1, /* force */ + dma->pages, NULL); + up_read(¤t->mm->mmap_sem); + if (err != dma->nr_pages) { + dma->nr_pages = (err >= 0) ? err : 0; + dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages); + return err < 0 ? err : -EINVAL; + } + return 0; +} + +int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction, + int nr_pages) +{ + dprintk(1,"init kernel [%d pages]\n",nr_pages); + dma->direction = direction; + dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT); + if (NULL == dma->vmalloc) { + dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages); + return -ENOMEM; + } + memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT); + dma->nr_pages = nr_pages; + return 0; +} + +int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction, + dma_addr_t addr, int nr_pages) +{ + dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n", + nr_pages,(unsigned long)addr); + dma->direction = direction; + if (0 == addr) + return -EINVAL; + + dma->bus_addr = addr; + dma->nr_pages = nr_pages; + return 0; +} + +int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma) +{ + MAGIC_CHECK(dma->magic,MAGIC_DMABUF); + BUG_ON(0 == dma->nr_pages); + + if (dma->pages) { + dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages, + dma->offset); + } + if (dma->vmalloc) { + dma->sglist = videobuf_vmalloc_to_sg + (dma->vmalloc,dma->nr_pages); + } + if (dma->bus_addr) { + dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL); + if (NULL != dma->sglist) { + dma->sglen = 1; + sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK; + dma->sglist[0].offset = dma->bus_addr & ~PAGE_MASK; + sg_dma_len(&dma->sglist[0]) = dma->nr_pages * PAGE_SIZE; + } + } + if (NULL == dma->sglist) { + dprintk(1,"scatterlist is NULL\n"); + return -ENOMEM; + } + + if (!dma->bus_addr) { + dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages, + dma->direction); + if (0 == dma->sglen) { + printk(KERN_WARNING + "%s: pci_map_sg failed\n",__FUNCTION__); + kfree(dma->sglist); + dma->sglist = NULL; + dma->sglen = 0; + return -EIO; + } + } + return 0; +} + +int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma) +{ + MAGIC_CHECK(dma->magic,MAGIC_DMABUF); + BUG_ON(!dma->sglen); + + if (!dma->bus_addr) + pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction); + return 0; +} + +int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma) +{ + MAGIC_CHECK(dma->magic,MAGIC_DMABUF); + if (!dma->sglen) + return 0; + + if (!dma->bus_addr) + pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction); + kfree(dma->sglist); + dma->sglist = NULL; + dma->sglen = 0; + return 0; +} + +int videobuf_dma_free(struct videobuf_dmabuf *dma) +{ + MAGIC_CHECK(dma->magic,MAGIC_DMABUF); + BUG_ON(dma->sglen); + + if (dma->pages) { + int i; + for (i=0; i < dma->nr_pages; i++) + page_cache_release(dma->pages[i]); + kfree(dma->pages); + dma->pages = NULL; + } + if (dma->vmalloc) { + vfree(dma->vmalloc); + dma->vmalloc = NULL; + } + if (dma->bus_addr) { + dma->bus_addr = 0; + } + dma->direction = PCI_DMA_NONE; + return 0; +} + +/* --------------------------------------------------------------------- */ + +void* videobuf_alloc(unsigned int size) +{ + struct videobuf_buffer *vb; + + vb = kmalloc(size,GFP_KERNEL); + if (NULL != vb) { + memset(vb,0,size); + videobuf_dma_init(&vb->dma); + init_waitqueue_head(&vb->done); + vb->magic = MAGIC_BUFFER; + } + return vb; +} + +int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr) +{ + int retval = 0; + DECLARE_WAITQUEUE(wait, current); + + MAGIC_CHECK(vb->magic,MAGIC_BUFFER); + add_wait_queue(&vb->done, &wait); + while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) { + if (non_blocking) { + retval = -EAGAIN; + break; + } + set_current_state(intr ? TASK_INTERRUPTIBLE + : TASK_UNINTERRUPTIBLE); + if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) + schedule(); + set_current_state(TASK_RUNNING); + if (intr && signal_pending(current)) { + dprintk(1,"buffer waiton: -EINTR\n"); + retval = -EINTR; + break; + } + } + remove_wait_queue(&vb->done, &wait); + return retval; +} + +int +videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb, + struct v4l2_framebuffer *fbuf) +{ + int err,pages; + dma_addr_t bus; + + MAGIC_CHECK(vb->magic,MAGIC_BUFFER); + switch (vb->memory) { + case V4L2_MEMORY_MMAP: + case V4L2_MEMORY_USERPTR: + if (0 == vb->baddr) { + /* no userspace addr -- kernel bounce buffer */ + pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT; + err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE, + pages); + if (0 != err) + return err; + } else { + /* dma directly to userspace */ + err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE, + vb->baddr,vb->bsize); + if (0 != err) + return err; + } + break; + case V4L2_MEMORY_OVERLAY: + if (NULL == fbuf) + return -EINVAL; + /* FIXME: need sanity checks for vb->boff */ + bus = (dma_addr_t)fbuf->base + vb->boff; + pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT; + err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE, + bus, pages); + if (0 != err) + return err; + break; + default: + BUG(); + } + err = videobuf_dma_pci_map(pci,&vb->dma); + if (0 != err) + return err; + + return 0; +} + +/* --------------------------------------------------------------------- */ + +void videobuf_queue_init(struct videobuf_queue* q, + struct videobuf_queue_ops *ops, + struct pci_dev *pci, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv) +{ + memset(q,0,sizeof(*q)); + q->irqlock = irqlock; + q->pci = pci; + q->type = type; + q->field = field; + q->msize = msize; + q->ops = ops; + q->priv_data = priv; + + init_MUTEX(&q->lock); + INIT_LIST_HEAD(&q->stream); +} + +int +videobuf_queue_is_busy(struct videobuf_queue *q) +{ + int i; + + if (q->streaming) { + dprintk(1,"busy: streaming active\n"); + return 1; + } + if (q->reading) { + dprintk(1,"busy: pending read #1\n"); + return 1; + } + if (q->read_buf) { + dprintk(1,"busy: pending read #2\n"); + return 1; + } + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + if (q->bufs[i]->map) { + dprintk(1,"busy: buffer #%d mapped\n",i); + return 1; + } + if (q->bufs[i]->state == STATE_QUEUED) { + dprintk(1,"busy: buffer #%d queued\n",i); + return 1; + } + if (q->bufs[i]->state == STATE_ACTIVE) { + dprintk(1,"busy: buffer #%d avtive\n",i); + return 1; + } + } + return 0; +} + +void +videobuf_queue_cancel(struct videobuf_queue *q) +{ + unsigned long flags; + int i; + + /* remove queued buffers from list */ + spin_lock_irqsave(q->irqlock,flags); + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + if (q->bufs[i]->state == STATE_QUEUED) { + list_del(&q->bufs[i]->queue); + q->bufs[i]->state = STATE_ERROR; + } + } + spin_unlock_irqrestore(q->irqlock,flags); + + /* free all buffers + clear queue */ + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + q->ops->buf_release(q,q->bufs[i]); + } + INIT_LIST_HEAD(&q->stream); +} + +/* --------------------------------------------------------------------- */ + +enum v4l2_field +videobuf_next_field(struct videobuf_queue *q) +{ + enum v4l2_field field = q->field; + + BUG_ON(V4L2_FIELD_ANY == field); + + if (V4L2_FIELD_ALTERNATE == field) { + if (V4L2_FIELD_TOP == q->last) { + field = V4L2_FIELD_BOTTOM; + q->last = V4L2_FIELD_BOTTOM; + } else { + field = V4L2_FIELD_TOP; + q->last = V4L2_FIELD_TOP; + } + } + return field; +} + +void +videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb, + enum v4l2_buf_type type) +{ + MAGIC_CHECK(vb->magic,MAGIC_BUFFER); + + b->index = vb->i; + b->type = type; + + b->memory = vb->memory; + switch (b->memory) { + case V4L2_MEMORY_MMAP: + b->m.offset = vb->boff; + b->length = vb->bsize; + break; + case V4L2_MEMORY_USERPTR: + b->m.userptr = vb->baddr; + b->length = vb->bsize; + break; + case V4L2_MEMORY_OVERLAY: + b->m.offset = vb->boff; + break; + } + + b->flags = 0; + if (vb->map) + b->flags |= V4L2_BUF_FLAG_MAPPED; + + switch (vb->state) { + case STATE_PREPARED: + case STATE_QUEUED: + case STATE_ACTIVE: + b->flags |= V4L2_BUF_FLAG_QUEUED; + break; + case STATE_DONE: + case STATE_ERROR: + b->flags |= V4L2_BUF_FLAG_DONE; + break; + case STATE_NEEDS_INIT: + case STATE_IDLE: + /* nothing */ + break; + } + + if (vb->input != UNSET) { + b->flags |= V4L2_BUF_FLAG_INPUT; + b->input = vb->input; + } + + b->field = vb->field; + b->timestamp = vb->ts; + b->bytesused = vb->size; + b->sequence = vb->field_count >> 1; +} + +int +videobuf_reqbufs(struct videobuf_queue *q, + struct v4l2_requestbuffers *req) +{ + unsigned int size,count; + int retval; + + if (req->type != q->type) + return -EINVAL; + if (req->count < 1) + return -EINVAL; + if (req->memory != V4L2_MEMORY_MMAP && + req->memory != V4L2_MEMORY_USERPTR && + req->memory != V4L2_MEMORY_OVERLAY) + return -EINVAL; + + if (q->streaming) + return -EBUSY; + if (!list_empty(&q->stream)) + return -EBUSY; + + down(&q->lock); + count = req->count; + if (count > VIDEO_MAX_FRAME) + count = VIDEO_MAX_FRAME; + size = 0; + q->ops->buf_setup(q,&count,&size); + size = PAGE_ALIGN(size); + dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n", + count, size, (count*size)>>PAGE_SHIFT); + + retval = videobuf_mmap_setup(q,count,size,req->memory); + if (retval < 0) + goto done; + + req->count = count; + + done: + up(&q->lock); + return retval; +} + +int +videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b) +{ + if (unlikely(b->type != q->type)) + return -EINVAL; + if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) + return -EINVAL; + if (unlikely(NULL == q->bufs[b->index])) + return -EINVAL; + videobuf_status(b,q->bufs[b->index],q->type); + return 0; +} + +int +videobuf_qbuf(struct videobuf_queue *q, + struct v4l2_buffer *b) +{ + struct videobuf_buffer *buf; + enum v4l2_field field; + unsigned long flags; + int retval; + + down(&q->lock); + retval = -EBUSY; + if (q->reading) + goto done; + retval = -EINVAL; + if (b->type != q->type) + goto done; + if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) + goto done; + buf = q->bufs[b->index]; + if (NULL == buf) + goto done; + MAGIC_CHECK(buf->magic,MAGIC_BUFFER); + if (buf->memory != b->memory) + goto done; + if (buf->state == STATE_QUEUED || + buf->state == STATE_ACTIVE) + goto done; + + if (b->flags & V4L2_BUF_FLAG_INPUT) { + if (b->input >= q->inputs) + goto done; + buf->input = b->input; + } else { + buf->input = UNSET; + } + + switch (b->memory) { + case V4L2_MEMORY_MMAP: + if (0 == buf->baddr) + goto done; + break; + case V4L2_MEMORY_USERPTR: + if (b->length < buf->bsize) + goto done; + if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr) + q->ops->buf_release(q,buf); + buf->baddr = b->m.userptr; + break; + case V4L2_MEMORY_OVERLAY: + buf->boff = b->m.offset; + break; + default: + goto done; + } + + field = videobuf_next_field(q); + retval = q->ops->buf_prepare(q,buf,field); + if (0 != retval) + goto done; + + list_add_tail(&buf->stream,&q->stream); + if (q->streaming) { + spin_lock_irqsave(q->irqlock,flags); + q->ops->buf_queue(q,buf); + spin_unlock_irqrestore(q->irqlock,flags); + } + retval = 0; + + done: + up(&q->lock); + return retval; +} + +int +videobuf_dqbuf(struct videobuf_queue *q, + struct v4l2_buffer *b, int nonblocking) +{ + struct videobuf_buffer *buf; + int retval; + + down(&q->lock); + retval = -EBUSY; + if (q->reading) + goto done; + retval = -EINVAL; + if (b->type != q->type) + goto done; + if (list_empty(&q->stream)) + goto done; + buf = list_entry(q->stream.next, struct videobuf_buffer, stream); + retval = videobuf_waiton(buf, nonblocking, 1); + if (retval < 0) + goto done; + switch (buf->state) { + case STATE_ERROR: + retval = -EIO; + /* fall through */ + case STATE_DONE: + videobuf_dma_pci_sync(q->pci,&buf->dma); + buf->state = STATE_IDLE; + break; + default: + retval = -EINVAL; + goto done; + } + list_del(&buf->stream); + memset(b,0,sizeof(*b)); + videobuf_status(b,buf,q->type); + + done: + up(&q->lock); + return retval; +} + +int videobuf_streamon(struct videobuf_queue *q) +{ + struct videobuf_buffer *buf; + struct list_head *list; + unsigned long flags; + int retval; + + down(&q->lock); + retval = -EBUSY; + if (q->reading) + goto done; + retval = 0; + if (q->streaming) + goto done; + q->streaming = 1; + spin_lock_irqsave(q->irqlock,flags); + list_for_each(list,&q->stream) { + buf = list_entry(list, struct videobuf_buffer, stream); + if (buf->state == STATE_PREPARED) + q->ops->buf_queue(q,buf); + } + spin_unlock_irqrestore(q->irqlock,flags); + + done: + up(&q->lock); + return retval; +} + +int videobuf_streamoff(struct videobuf_queue *q) +{ + int retval = -EINVAL; + + down(&q->lock); + if (!q->streaming) + goto done; + videobuf_queue_cancel(q); + q->streaming = 0; + retval = 0; + + done: + up(&q->lock); + return retval; +} + +static ssize_t +videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data, + size_t count, loff_t *ppos) +{ + enum v4l2_field field; + unsigned long flags; + int retval; + + /* setup stuff */ + retval = -ENOMEM; + q->read_buf = videobuf_alloc(q->msize); + if (NULL == q->read_buf) + goto done; + + q->read_buf->memory = V4L2_MEMORY_USERPTR; + q->read_buf->baddr = (unsigned long)data; + q->read_buf->bsize = count; + field = videobuf_next_field(q); + retval = q->ops->buf_prepare(q,q->read_buf,field); + if (0 != retval) + goto done; + + /* start capture & wait */ + spin_lock_irqsave(q->irqlock,flags); + q->ops->buf_queue(q,q->read_buf); + spin_unlock_irqrestore(q->irqlock,flags); + retval = videobuf_waiton(q->read_buf,0,0); + if (0 == retval) { + videobuf_dma_pci_sync(q->pci,&q->read_buf->dma); + if (STATE_ERROR == q->read_buf->state) + retval = -EIO; + else + retval = q->read_buf->size; + } + + done: + /* cleanup */ + q->ops->buf_release(q,q->read_buf); + kfree(q->read_buf); + q->read_buf = NULL; + return retval; +} + +ssize_t videobuf_read_one(struct videobuf_queue *q, + char __user *data, size_t count, loff_t *ppos, + int nonblocking) +{ + enum v4l2_field field; + unsigned long flags; + unsigned size, nbufs, bytes; + int retval; + + down(&q->lock); + + nbufs = 1; size = 0; + q->ops->buf_setup(q,&nbufs,&size); + if (NULL == q->read_buf && + count >= size && + !nonblocking) { + retval = videobuf_read_zerocopy(q,data,count,ppos); + if (retval >= 0 || retval == -EIO) + /* ok, all done */ + goto done; + /* fallback to kernel bounce buffer on failures */ + } + + if (NULL == q->read_buf) { + /* need to capture a new frame */ + retval = -ENOMEM; + q->read_buf = videobuf_alloc(q->msize); + if (NULL == q->read_buf) + goto done; + q->read_buf->memory = V4L2_MEMORY_USERPTR; + field = videobuf_next_field(q); + retval = q->ops->buf_prepare(q,q->read_buf,field); + if (0 != retval) + goto done; + spin_lock_irqsave(q->irqlock,flags); + q->ops->buf_queue(q,q->read_buf); + spin_unlock_irqrestore(q->irqlock,flags); + q->read_off = 0; + } + + /* wait until capture is done */ + retval = videobuf_waiton(q->read_buf, nonblocking, 1); + if (0 != retval) + goto done; + videobuf_dma_pci_sync(q->pci,&q->read_buf->dma); + + if (STATE_ERROR == q->read_buf->state) { + /* catch I/O errors */ + q->ops->buf_release(q,q->read_buf); + kfree(q->read_buf); + q->read_buf = NULL; + retval = -EIO; + goto done; + } + + /* copy to userspace */ + bytes = count; + if (bytes > q->read_buf->size - q->read_off) + bytes = q->read_buf->size - q->read_off; + retval = -EFAULT; + if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes)) + goto done; + + retval = bytes; + q->read_off += bytes; + if (q->read_off == q->read_buf->size) { + /* all data copied, cleanup */ + q->ops->buf_release(q,q->read_buf); + kfree(q->read_buf); + q->read_buf = NULL; + } + + done: + up(&q->lock); + return retval; +} + +int videobuf_read_start(struct videobuf_queue *q) +{ + enum v4l2_field field; + unsigned long flags; + int count = 0, size = 0; + int err, i; + + q->ops->buf_setup(q,&count,&size); + if (count < 2) + count = 2; + if (count > VIDEO_MAX_FRAME) + count = VIDEO_MAX_FRAME; + size = PAGE_ALIGN(size); + + err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR); + if (err) + return err; + for (i = 0; i < count; i++) { + field = videobuf_next_field(q); + err = q->ops->buf_prepare(q,q->bufs[i],field); + if (err) + return err; + list_add_tail(&q->bufs[i]->stream, &q->stream); + } + spin_lock_irqsave(q->irqlock,flags); + for (i = 0; i < count; i++) + q->ops->buf_queue(q,q->bufs[i]); + spin_unlock_irqrestore(q->irqlock,flags); + q->reading = 1; + return 0; +} + +void videobuf_read_stop(struct videobuf_queue *q) +{ + int i; + + videobuf_queue_cancel(q); + videobuf_mmap_free(q); + INIT_LIST_HEAD(&q->stream); + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + kfree(q->bufs[i]); + q->bufs[i] = NULL; + } + q->read_buf = NULL; + q->reading = 0; +} + +ssize_t videobuf_read_stream(struct videobuf_queue *q, + char __user *data, size_t count, loff_t *ppos, + int vbihack, int nonblocking) +{ + unsigned int *fc, bytes; + int err, retval; + unsigned long flags; + + dprintk(2,"%s\n",__FUNCTION__); + down(&q->lock); + retval = -EBUSY; + if (q->streaming) + goto done; + if (!q->reading) { + retval = videobuf_read_start(q); + if (retval < 0) + goto done; + } + + retval = 0; + while (count > 0) { + /* get / wait for data */ + if (NULL == q->read_buf) { + q->read_buf = list_entry(q->stream.next, + struct videobuf_buffer, + stream); + list_del(&q->read_buf->stream); + q->read_off = 0; + } + err = videobuf_waiton(q->read_buf, nonblocking, 1); + if (err < 0) { + if (0 == retval) + retval = err; + break; + } + + if (q->read_buf->state == STATE_DONE) { + if (vbihack) { + /* dirty, undocumented hack -- pass the frame counter + * within the last four bytes of each vbi data block. + * We need that one to maintain backward compatibility + * to all vbi decoding software out there ... */ + fc = (unsigned int*)q->read_buf->dma.vmalloc; + fc += (q->read_buf->size>>2) -1; + *fc = q->read_buf->field_count >> 1; + dprintk(1,"vbihack: %d\n",*fc); + } + + /* copy stuff */ + bytes = count; + if (bytes > q->read_buf->size - q->read_off) + bytes = q->read_buf->size - q->read_off; + if (copy_to_user(data + retval, + q->read_buf->dma.vmalloc + q->read_off, + bytes)) { + if (0 == retval) + retval = -EFAULT; + break; + } + count -= bytes; + retval += bytes; + q->read_off += bytes; + } else { + /* some error */ + q->read_off = q->read_buf->size; + if (0 == retval) + retval = -EIO; + } + + /* requeue buffer when done with copying */ + if (q->read_off == q->read_buf->size) { + list_add_tail(&q->read_buf->stream, + &q->stream); + spin_lock_irqsave(q->irqlock,flags); + q->ops->buf_queue(q,q->read_buf); + spin_unlock_irqrestore(q->irqlock,flags); + q->read_buf = NULL; + } + if (retval < 0) + break; + } + + done: + up(&q->lock); + return retval; +} + +unsigned int videobuf_poll_stream(struct file *file, + struct videobuf_queue *q, + poll_table *wait) +{ + struct videobuf_buffer *buf = NULL; + unsigned int rc = 0; + + down(&q->lock); + if (q->streaming) { + if (!list_empty(&q->stream)) + buf = list_entry(q->stream.next, + struct videobuf_buffer, stream); + } else { + if (!q->reading) + videobuf_read_start(q); + if (!q->reading) { + rc = POLLERR; + } else if (NULL == q->read_buf) { + q->read_buf = list_entry(q->stream.next, + struct videobuf_buffer, + stream); + list_del(&q->read_buf->stream); + q->read_off = 0; + } + buf = q->read_buf; + } + if (!buf) + rc = POLLERR; + + if (0 == rc) { + poll_wait(file, &buf->done, wait); + if (buf->state == STATE_DONE || + buf->state == STATE_ERROR) + rc = POLLIN|POLLRDNORM; + } + up(&q->lock); + return rc; +} + +/* --------------------------------------------------------------------- */ + +static void +videobuf_vm_open(struct vm_area_struct *vma) +{ + struct videobuf_mapping *map = vma->vm_private_data; + + dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map, + map->count,vma->vm_start,vma->vm_end); + map->count++; +} + +static void +videobuf_vm_close(struct vm_area_struct *vma) +{ + struct videobuf_mapping *map = vma->vm_private_data; + struct videobuf_queue *q = map->q; + int i; + + dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map, + map->count,vma->vm_start,vma->vm_end); + + map->count--; + if (0 == map->count) { + dprintk(1,"munmap %p q=%p\n",map,q); + down(&q->lock); + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + if (q->bufs[i]) + ; + if (q->bufs[i]->map != map) + continue; + q->bufs[i]->map = NULL; + q->bufs[i]->baddr = 0; + q->ops->buf_release(q,q->bufs[i]); + } + up(&q->lock); + kfree(map); + } + return; +} + +/* + * Get a anonymous page for the mapping. Make sure we can DMA to that + * memory location with 32bit PCI devices (i.e. don't use highmem for + * now ...). Bounce buffers don't work very well for the data rates + * video capture has. + */ +static struct page* +videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr, + int *type) +{ + struct page *page; + + dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n", + vaddr,vma->vm_start,vma->vm_end); + if (vaddr > vma->vm_end) + return NOPAGE_SIGBUS; + page = alloc_page(GFP_USER); + if (!page) + return NOPAGE_OOM; + clear_user_page(page_address(page), vaddr, page); + if (type) + *type = VM_FAULT_MINOR; + return page; +} + +static struct vm_operations_struct videobuf_vm_ops = +{ + .open = videobuf_vm_open, + .close = videobuf_vm_close, + .nopage = videobuf_vm_nopage, +}; + +int videobuf_mmap_setup(struct videobuf_queue *q, + unsigned int bcount, unsigned int bsize, + enum v4l2_memory memory) +{ + unsigned int i; + int err; + + err = videobuf_mmap_free(q); + if (0 != err) + return err; + + for (i = 0; i < bcount; i++) { + q->bufs[i] = videobuf_alloc(q->msize); + q->bufs[i]->i = i; + q->bufs[i]->input = UNSET; + q->bufs[i]->memory = memory; + q->bufs[i]->bsize = bsize; + switch (memory) { + case V4L2_MEMORY_MMAP: + q->bufs[i]->boff = bsize * i; + break; + case V4L2_MEMORY_USERPTR: + case V4L2_MEMORY_OVERLAY: + /* nothing */ + break; + } + } + dprintk(1,"mmap setup: %d buffers, %d bytes each\n", + bcount,bsize); + return 0; +} + +int videobuf_mmap_free(struct videobuf_queue *q) +{ + int i; + + for (i = 0; i < VIDEO_MAX_FRAME; i++) + if (q->bufs[i] && q->bufs[i]->map) + return -EBUSY; + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + q->ops->buf_release(q,q->bufs[i]); + kfree(q->bufs[i]); + q->bufs[i] = NULL; + } + return 0; +} + +int videobuf_mmap_mapper(struct videobuf_queue *q, + struct vm_area_struct *vma) +{ + struct videobuf_mapping *map; + unsigned int first,last,size,i; + int retval; + + down(&q->lock); + retval = -EINVAL; + if (!(vma->vm_flags & VM_WRITE)) { + dprintk(1,"mmap app bug: PROT_WRITE please\n"); + goto done; + } + if (!(vma->vm_flags & VM_SHARED)) { + dprintk(1,"mmap app bug: MAP_SHARED please\n"); + goto done; + } + + /* look for first buffer to map */ + for (first = 0; first < VIDEO_MAX_FRAME; first++) { + if (NULL == q->bufs[first]) + continue; + if (V4L2_MEMORY_MMAP != q->bufs[first]->memory) + continue; + if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT)) + break; + } + if (VIDEO_MAX_FRAME == first) { + dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n", + (vma->vm_pgoff << PAGE_SHIFT)); + goto done; + } + + /* look for last buffer to map */ + for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) { + if (NULL == q->bufs[last]) + continue; + if (V4L2_MEMORY_MMAP != q->bufs[last]->memory) + continue; + if (q->bufs[last]->map) { + retval = -EBUSY; + goto done; + } + size += q->bufs[last]->bsize; + if (size == (vma->vm_end - vma->vm_start)) + break; + } + if (VIDEO_MAX_FRAME == last) { + dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n", + (vma->vm_end - vma->vm_start)); + goto done; + } + + /* create mapping + update buffer list */ + retval = -ENOMEM; + map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL); + if (NULL == map) + goto done; + for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) { + q->bufs[i]->map = map; + q->bufs[i]->baddr = vma->vm_start + size; + } + map->count = 1; + map->start = vma->vm_start; + map->end = vma->vm_end; + map->q = q; + vma->vm_ops = &videobuf_vm_ops; + vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED; + vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */ + vma->vm_private_data = map; + dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n", + map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last); + retval = 0; + + done: + up(&q->lock); + return retval; +} + +/* --------------------------------------------------------------------- */ + +EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg); + +EXPORT_SYMBOL_GPL(videobuf_dma_init); +EXPORT_SYMBOL_GPL(videobuf_dma_init_user); +EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel); +EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay); +EXPORT_SYMBOL_GPL(videobuf_dma_pci_map); +EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync); +EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap); +EXPORT_SYMBOL_GPL(videobuf_dma_free); + +EXPORT_SYMBOL_GPL(videobuf_alloc); +EXPORT_SYMBOL_GPL(videobuf_waiton); +EXPORT_SYMBOL_GPL(videobuf_iolock); + +EXPORT_SYMBOL_GPL(videobuf_queue_init); +EXPORT_SYMBOL_GPL(videobuf_queue_cancel); +EXPORT_SYMBOL_GPL(videobuf_queue_is_busy); + +EXPORT_SYMBOL_GPL(videobuf_next_field); +EXPORT_SYMBOL_GPL(videobuf_status); +EXPORT_SYMBOL_GPL(videobuf_reqbufs); +EXPORT_SYMBOL_GPL(videobuf_querybuf); +EXPORT_SYMBOL_GPL(videobuf_qbuf); +EXPORT_SYMBOL_GPL(videobuf_dqbuf); +EXPORT_SYMBOL_GPL(videobuf_streamon); +EXPORT_SYMBOL_GPL(videobuf_streamoff); + +EXPORT_SYMBOL_GPL(videobuf_read_start); +EXPORT_SYMBOL_GPL(videobuf_read_stop); +EXPORT_SYMBOL_GPL(videobuf_read_stream); +EXPORT_SYMBOL_GPL(videobuf_read_one); +EXPORT_SYMBOL_GPL(videobuf_poll_stream); + +EXPORT_SYMBOL_GPL(videobuf_mmap_setup); +EXPORT_SYMBOL_GPL(videobuf_mmap_free); +EXPORT_SYMBOL_GPL(videobuf_mmap_mapper); + +/* + * Local variables: + * c-basic-offset: 8 + * End: + */ |