diff options
Diffstat (limited to 'drivers/media/video/videobuf-dma-sg.c')
-rw-r--r-- | drivers/media/video/videobuf-dma-sg.c | 633 |
1 files changed, 0 insertions, 633 deletions
diff --git a/drivers/media/video/videobuf-dma-sg.c b/drivers/media/video/videobuf-dma-sg.c deleted file mode 100644 index f300deafd26..00000000000 --- a/drivers/media/video/videobuf-dma-sg.c +++ /dev/null @@ -1,633 +0,0 @@ -/* - * helper functions for SG DMA video4linux capture buffers - * - * The functions expect the hardware being able to scatter gather - * (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. - * - * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org> - * - * Highly based on video-buf written originally by: - * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> - * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org> - * (c) 2006 Ted Walther and John Sokol - * - * 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 - */ - -#include <linux/init.h> -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/interrupt.h> - -#include <linux/dma-mapping.h> -#include <linux/vmalloc.h> -#include <linux/pagemap.h> -#include <linux/scatterlist.h> -#include <asm/page.h> -#include <asm/pgtable.h> - -#include <media/videobuf-dma-sg.h> - -#define MAGIC_DMABUF 0x19721112 -#define MAGIC_SG_MEM 0x17890714 - -#define MAGIC_CHECK(is, should) \ - if (unlikely((is) != (should))) { \ - printk(KERN_ERR "magic mismatch: %x (expected %x)\n", \ - is, should); \ - BUG(); \ - } - -static int debug; -module_param(debug, int, 0644); - -MODULE_DESCRIPTION("helper module to manage video4linux dma sg buffers"); -MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>"); -MODULE_LICENSE("GPL"); - -#define dprintk(level, fmt, arg...) \ - if (debug >= level) \ - printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg) - -/* --------------------------------------------------------------------- */ - -/* - * Return a scatterlist for some page-aligned vmalloc()'ed memory - * block (NULL on errors). Memory for the scatterlist is allocated - * using kmalloc. The caller must free the memory. - */ -static struct scatterlist *videobuf_vmalloc_to_sg(unsigned char *virt, - int nr_pages) -{ - struct scatterlist *sglist; - struct page *pg; - int i; - - sglist = vzalloc(nr_pages * sizeof(*sglist)); - if (NULL == sglist) - return NULL; - sg_init_table(sglist, nr_pages); - for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) { - pg = vmalloc_to_page(virt); - if (NULL == pg) - goto err; - BUG_ON(PageHighMem(pg)); - sg_set_page(&sglist[i], pg, PAGE_SIZE, 0); - } - return sglist; - -err: - vfree(sglist); - return NULL; -} - -/* - * Return a scatterlist for a an array of userpages (NULL on errors). - * Memory for the scatterlist is allocated using kmalloc. The caller - * must free the memory. - */ -static struct scatterlist *videobuf_pages_to_sg(struct page **pages, - int nr_pages, int offset, size_t size) -{ - struct scatterlist *sglist; - int i; - - if (NULL == pages[0]) - return NULL; - sglist = vmalloc(nr_pages * sizeof(*sglist)); - if (NULL == sglist) - return NULL; - sg_init_table(sglist, nr_pages); - - if (PageHighMem(pages[0])) - /* DMA to highmem pages might not work */ - goto highmem; - sg_set_page(&sglist[0], pages[0], - min_t(size_t, PAGE_SIZE - offset, size), offset); - size -= min_t(size_t, PAGE_SIZE - offset, size); - for (i = 1; i < nr_pages; i++) { - if (NULL == pages[i]) - goto nopage; - if (PageHighMem(pages[i])) - goto highmem; - sg_set_page(&sglist[i], pages[i], min_t(size_t, PAGE_SIZE, size), 0); - size -= min_t(size_t, PAGE_SIZE, size); - } - return sglist; - -nopage: - dprintk(2, "sgl: oops - no page\n"); - vfree(sglist); - return NULL; - -highmem: - dprintk(2, "sgl: oops - highmem page\n"); - vfree(sglist); - return NULL; -} - -/* --------------------------------------------------------------------- */ - -struct videobuf_dmabuf *videobuf_to_dma(struct videobuf_buffer *buf) -{ - struct videobuf_dma_sg_memory *mem = buf->priv; - BUG_ON(!mem); - - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - - return &mem->dma; -} -EXPORT_SYMBOL_GPL(videobuf_to_dma); - -void videobuf_dma_init(struct videobuf_dmabuf *dma) -{ - memset(dma, 0, sizeof(*dma)); - dma->magic = MAGIC_DMABUF; -} -EXPORT_SYMBOL_GPL(videobuf_dma_init); - -static int videobuf_dma_init_user_locked(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 DMA_FROM_DEVICE: - rw = READ; - break; - case DMA_TO_DEVICE: - 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->size = size; - 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); - - err = get_user_pages(current, current->mm, - data & PAGE_MASK, dma->nr_pages, - rw == READ, 1, /* force */ - dma->pages, NULL); - - 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_user(struct videobuf_dmabuf *dma, int direction, - unsigned long data, unsigned long size) -{ - int ret; - - down_read(¤t->mm->mmap_sem); - ret = videobuf_dma_init_user_locked(dma, direction, data, size); - up_read(¤t->mm->mmap_sem); - - return ret; -} -EXPORT_SYMBOL_GPL(videobuf_dma_init_user); - -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->vaddr = vmalloc_32(nr_pages << PAGE_SHIFT); - if (NULL == dma->vaddr) { - dprintk(1, "vmalloc_32(%d pages) failed\n", nr_pages); - return -ENOMEM; - } - - dprintk(1, "vmalloc is at addr 0x%08lx, size=%d\n", - (unsigned long)dma->vaddr, - nr_pages << PAGE_SHIFT); - - memset(dma->vaddr, 0, nr_pages << PAGE_SHIFT); - dma->nr_pages = nr_pages; - - return 0; -} -EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel); - -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; -} -EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay); - -int videobuf_dma_map(struct device *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, dma->size); - } - if (dma->vaddr) { - dma->sglist = videobuf_vmalloc_to_sg(dma->vaddr, - dma->nr_pages); - } - if (dma->bus_addr) { - dma->sglist = vmalloc(sizeof(*dma->sglist)); - 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 = dma_map_sg(dev, dma->sglist, - dma->nr_pages, dma->direction); - if (0 == dma->sglen) { - printk(KERN_WARNING - "%s: videobuf_map_sg failed\n", __func__); - vfree(dma->sglist); - dma->sglist = NULL; - dma->sglen = 0; - return -ENOMEM; - } - } - - return 0; -} -EXPORT_SYMBOL_GPL(videobuf_dma_map); - -int videobuf_dma_unmap(struct device *dev, struct videobuf_dmabuf *dma) -{ - MAGIC_CHECK(dma->magic, MAGIC_DMABUF); - - if (!dma->sglen) - return 0; - - dma_unmap_sg(dev, dma->sglist, dma->sglen, dma->direction); - - vfree(dma->sglist); - dma->sglist = NULL; - dma->sglen = 0; - - return 0; -} -EXPORT_SYMBOL_GPL(videobuf_dma_unmap); - -int videobuf_dma_free(struct videobuf_dmabuf *dma) -{ - int i; - MAGIC_CHECK(dma->magic, MAGIC_DMABUF); - BUG_ON(dma->sglen); - - if (dma->pages) { - for (i = 0; i < dma->nr_pages; i++) - page_cache_release(dma->pages[i]); - kfree(dma->pages); - dma->pages = NULL; - } - - vfree(dma->vaddr); - dma->vaddr = NULL; - - if (dma->bus_addr) - dma->bus_addr = 0; - dma->direction = DMA_NONE; - - return 0; -} -EXPORT_SYMBOL_GPL(videobuf_dma_free); - -/* --------------------------------------------------------------------- */ - -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; - struct videobuf_dma_sg_memory *mem; - 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); - videobuf_queue_lock(q); - for (i = 0; i < VIDEO_MAX_FRAME; i++) { - if (NULL == q->bufs[i]) - continue; - mem = q->bufs[i]->priv; - if (!mem) - continue; - - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - - 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]); - } - videobuf_queue_unlock(q); - 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 int videobuf_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) -{ - struct page *page; - - dprintk(3, "fault: fault @ %08lx [vma %08lx-%08lx]\n", - (unsigned long)vmf->virtual_address, - vma->vm_start, vma->vm_end); - - page = alloc_page(GFP_USER | __GFP_DMA32); - if (!page) - return VM_FAULT_OOM; - clear_user_highpage(page, (unsigned long)vmf->virtual_address); - vmf->page = page; - - return 0; -} - -static const struct vm_operations_struct videobuf_vm_ops = { - .open = videobuf_vm_open, - .close = videobuf_vm_close, - .fault = videobuf_vm_fault, -}; - -/* --------------------------------------------------------------------- - * SG handlers for the generic methods - */ - -/* Allocated area consists on 3 parts: - struct video_buffer - struct <driver>_buffer (cx88_buffer, saa7134_buf, ...) - struct videobuf_dma_sg_memory - */ - -static struct videobuf_buffer *__videobuf_alloc_vb(size_t size) -{ - struct videobuf_dma_sg_memory *mem; - struct videobuf_buffer *vb; - - vb = kzalloc(size + sizeof(*mem), GFP_KERNEL); - if (!vb) - return vb; - - mem = vb->priv = ((char *)vb) + size; - mem->magic = MAGIC_SG_MEM; - - videobuf_dma_init(&mem->dma); - - dprintk(1, "%s: allocated at %p(%ld+%ld) & %p(%ld)\n", - __func__, vb, (long)sizeof(*vb), (long)size - sizeof(*vb), - mem, (long)sizeof(*mem)); - - return vb; -} - -static void *__videobuf_to_vaddr(struct videobuf_buffer *buf) -{ - struct videobuf_dma_sg_memory *mem = buf->priv; - BUG_ON(!mem); - - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - - return mem->dma.vaddr; -} - -static int __videobuf_iolock(struct videobuf_queue *q, - struct videobuf_buffer *vb, - struct v4l2_framebuffer *fbuf) -{ - int err, pages; - dma_addr_t bus; - struct videobuf_dma_sg_memory *mem = vb->priv; - BUG_ON(!mem); - - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - - 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(&mem->dma, - DMA_FROM_DEVICE, - pages); - if (0 != err) - return err; - } else if (vb->memory == V4L2_MEMORY_USERPTR) { - /* dma directly to userspace */ - err = videobuf_dma_init_user(&mem->dma, - DMA_FROM_DEVICE, - vb->baddr, vb->bsize); - if (0 != err) - return err; - } else { - /* NOTE: HACK: videobuf_iolock on V4L2_MEMORY_MMAP - buffers can only be called from videobuf_qbuf - we take current->mm->mmap_sem there, to prevent - locking inversion, so don't take it here */ - - err = videobuf_dma_init_user_locked(&mem->dma, - DMA_FROM_DEVICE, - 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 */ - /* - * Using a double cast to avoid compiler warnings when - * building for PAE. Compiler doesn't like direct casting - * of a 32 bit ptr to 64 bit integer. - */ - bus = (dma_addr_t)(unsigned long)fbuf->base + vb->boff; - pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT; - err = videobuf_dma_init_overlay(&mem->dma, DMA_FROM_DEVICE, - bus, pages); - if (0 != err) - return err; - break; - default: - BUG(); - } - err = videobuf_dma_map(q->dev, &mem->dma); - if (0 != err) - return err; - - return 0; -} - -static int __videobuf_sync(struct videobuf_queue *q, - struct videobuf_buffer *buf) -{ - struct videobuf_dma_sg_memory *mem = buf->priv; - BUG_ON(!mem || !mem->dma.sglen); - - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - MAGIC_CHECK(mem->dma.magic, MAGIC_DMABUF); - - dma_sync_sg_for_cpu(q->dev, mem->dma.sglist, - mem->dma.sglen, mem->dma.direction); - - return 0; -} - -static int __videobuf_mmap_mapper(struct videobuf_queue *q, - struct videobuf_buffer *buf, - struct vm_area_struct *vma) -{ - struct videobuf_dma_sg_memory *mem = buf->priv; - struct videobuf_mapping *map; - unsigned int first, last, size = 0, i; - int retval; - - retval = -EINVAL; - - BUG_ON(!mem); - MAGIC_CHECK(mem->magic, MAGIC_SG_MEM); - - /* look for first buffer to map */ - for (first = 0; first < VIDEO_MAX_FRAME; first++) { - if (buf == q->bufs[first]) { - size = PAGE_ALIGN(q->bufs[first]->bsize); - break; - } - } - - /* paranoia, should never happen since buf is always valid. */ - if (!size) { - dprintk(1, "mmap app bug: offset invalid [offset=0x%lx]\n", - (vma->vm_pgoff << PAGE_SHIFT)); - goto done; - } - - last = first; - - /* create mapping + update buffer list */ - retval = -ENOMEM; - map = kmalloc(sizeof(struct videobuf_mapping), GFP_KERNEL); - if (NULL == map) - goto done; - - size = 0; - for (i = first; i <= last; i++) { - if (NULL == q->bufs[i]) - continue; - q->bufs[i]->map = map; - q->bufs[i]->baddr = vma->vm_start + size; - size += PAGE_ALIGN(q->bufs[i]->bsize); - } - - map->count = 1; - 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: - return retval; -} - -static struct videobuf_qtype_ops sg_ops = { - .magic = MAGIC_QTYPE_OPS, - - .alloc_vb = __videobuf_alloc_vb, - .iolock = __videobuf_iolock, - .sync = __videobuf_sync, - .mmap_mapper = __videobuf_mmap_mapper, - .vaddr = __videobuf_to_vaddr, -}; - -void *videobuf_sg_alloc(size_t size) -{ - struct videobuf_queue q; - - /* Required to make generic handler to call __videobuf_alloc */ - q.int_ops = &sg_ops; - - q.msize = size; - - return videobuf_alloc_vb(&q); -} -EXPORT_SYMBOL_GPL(videobuf_sg_alloc); - -void videobuf_queue_sg_init(struct videobuf_queue *q, - const struct videobuf_queue_ops *ops, - struct device *dev, - spinlock_t *irqlock, - enum v4l2_buf_type type, - enum v4l2_field field, - unsigned int msize, - void *priv, - struct mutex *ext_lock) -{ - videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize, - priv, &sg_ops, ext_lock); -} -EXPORT_SYMBOL_GPL(videobuf_queue_sg_init); - |