static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
unsigned long size,
enum dma_data_direction dma_dir)
{
struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
struct sg_table *sgt;
DEFINE_DMA_ATTRS(attrs);
struct frame_vector *vec;
dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
buf->vaddr = NULL;
buf->dev = conf->dev;
buf->dma_dir = dma_dir;
buf->offset = vaddr & ~PAGE_MASK;
buf->size = size;
buf->dma_sgt = &buf->sg_table;
vec = vb2_create_framevec(vaddr, size, buf->dma_dir == DMA_FROM_DEVICE);
if (IS_ERR(vec))
goto userptr_fail_pfnvec;
buf->vec = vec;
buf->pages = frame_vector_pages(vec);
if (IS_ERR(buf->pages))
goto userptr_fail_sgtable;
buf->num_pages = frame_vector_count(vec);
if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
buf->num_pages, buf->offset, size, 0))
goto userptr_fail_sgtable;
sgt = &buf->sg_table;
/*
* No need to sync to the device, this will happen later when the
* prepare() memop is called.
*/
sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir, &attrs);
if (!sgt->nents)
goto userptr_fail_map;
return buf;
userptr_fail_map:
sg_free_table(&buf->sg_table);
userptr_fail_sgtable:
vb2_destroy_framevec(vec);
userptr_fail_pfnvec:
kfree(buf);
return NULL;
}
static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
unsigned long size,
enum dma_data_direction dma_dir)
{
struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
unsigned long first, last;
int num_pages_from_user;
struct vm_area_struct *vma;
struct sg_table *sgt;
DEFINE_DMA_ATTRS(attrs);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,6,0)
dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
#endif
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
buf->vaddr = NULL;
buf->dev = conf->dev;
buf->dma_dir = dma_dir;
buf->offset = vaddr & ~PAGE_MASK;
buf->size = size;
buf->dma_sgt = &buf->sg_table;
first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
buf->num_pages = last - first + 1;
buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
GFP_KERNEL);
if (!buf->pages)
goto userptr_fail_alloc_pages;
vma = find_vma(current->mm, vaddr);
if (!vma) {
dprintk(1, "no vma for address %lu\n", vaddr);
goto userptr_fail_find_vma;
}
if (vma->vm_end < vaddr + size) {
dprintk(1, "vma at %lu is too small for %lu bytes\n",
vaddr, size);
goto userptr_fail_find_vma;
}
buf->vma = vb2_get_vma(vma);
if (!buf->vma) {
dprintk(1, "failed to copy vma\n");
goto userptr_fail_find_vma;
}
if (vma_is_io(buf->vma)) {
for (num_pages_from_user = 0;
num_pages_from_user < buf->num_pages;
++num_pages_from_user, vaddr += PAGE_SIZE) {
unsigned long pfn;
if (follow_pfn(vma, vaddr, &pfn)) {
dprintk(1, "no page for address %lu\n", vaddr);
break;
}
buf->pages[num_pages_from_user] = pfn_to_page(pfn);
}
} else
num_pages_from_user = get_user_pages(current, current->mm,
vaddr & PAGE_MASK,
buf->num_pages,
buf->dma_dir == DMA_FROM_DEVICE,
1, /* force */
buf->pages,
NULL);
if (num_pages_from_user != buf->num_pages)
goto userptr_fail_get_user_pages;
if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
buf->num_pages, buf->offset, size, 0))
goto userptr_fail_alloc_table_from_pages;
sgt = &buf->sg_table;
/*
* No need to sync to the device, this will happen later when the
* prepare() memop is called.
*/
sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir, &attrs);
if (!sgt->nents)
goto userptr_fail_map;
return buf;
userptr_fail_map:
sg_free_table(&buf->sg_table);
userptr_fail_alloc_table_from_pages:
userptr_fail_get_user_pages:
dprintk(1, "get_user_pages requested/got: %d/%d]\n",
buf->num_pages, num_pages_from_user);
if (!vma_is_io(buf->vma))
while (--num_pages_from_user >= 0)
put_page(buf->pages[num_pages_from_user]);
vb2_put_vma(buf->vma);
userptr_fail_find_vma:
kfree(buf->pages);
userptr_fail_alloc_pages:
kfree(buf);
return NULL;
}
static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size,
enum dma_data_direction dma_dir, gfp_t gfp_flags)
{
struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
struct sg_table *sgt;
int ret;
int num_pages;
DEFINE_DMA_ATTRS(attrs);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,6,0)
dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
#endif
if (WARN_ON(alloc_ctx == NULL))
return NULL;
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
buf->vaddr = NULL;
buf->dma_dir = dma_dir;
buf->offset = 0;
buf->size = size;
/* size is already page aligned */
buf->num_pages = size >> PAGE_SHIFT;
buf->dma_sgt = &buf->sg_table;
buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
GFP_KERNEL);
if (!buf->pages)
goto fail_pages_array_alloc;
ret = vb2_dma_sg_alloc_compacted(buf, gfp_flags);
if (ret)
goto fail_pages_alloc;
ret = sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
buf->num_pages, 0, size, GFP_KERNEL);
if (ret)
goto fail_table_alloc;
/* Prevent the device from being released while the buffer is used */
buf->dev = get_device(conf->dev);
sgt = &buf->sg_table;
/*
* No need to sync to the device, this will happen later when the
* prepare() memop is called.
*/
sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir, &attrs);
if (!sgt->nents)
goto fail_map;
buf->handler.refcount = &buf->refcount;
buf->handler.put = vb2_dma_sg_put;
buf->handler.arg = buf;
atomic_inc(&buf->refcount);
dprintk(1, "%s: Allocated buffer of %d pages\n",
__func__, buf->num_pages);
return buf;
fail_map:
put_device(buf->dev);
sg_free_table(buf->dma_sgt);
fail_table_alloc:
num_pages = buf->num_pages;
while (num_pages--)
__free_page(buf->pages[num_pages]);
fail_pages_alloc:
kfree(buf->pages);
fail_pages_array_alloc:
kfree(buf);
return NULL;
}
