diff options
Diffstat (limited to 'drivers/media/v4l2-core/videobuf2-dma-contig.c')
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-dma-contig.c | 821 |
1 files changed, 821 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c new file mode 100644 index 0000000..abfee5d --- /dev/null +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -0,0 +1,821 @@ +/* + * videobuf2-dma-contig.c - DMA contig memory allocator for videobuf2 + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak <pawel@osciak.com> + * + * 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. + */ + +#include <linux/dma-buf.h> +#include <linux/module.h> +#include <linux/scatterlist.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/dma-mapping.h> + +#include <media/videobuf2-core.h> +#include <media/videobuf2-dma-contig.h> +#include <media/videobuf2-memops.h> + +struct vb2_dc_conf { + struct device *dev; +}; + +struct vb2_dc_buf { + struct device *dev; + void *vaddr; + unsigned long size; + dma_addr_t dma_addr; + enum dma_data_direction dma_dir; + struct sg_table *dma_sgt; + + /* MMAP related */ + struct vb2_vmarea_handler handler; + atomic_t refcount; + struct sg_table *sgt_base; + + /* USERPTR related */ + struct vm_area_struct *vma; + + /* DMABUF related */ + struct dma_buf_attachment *db_attach; +}; + +/*********************************************/ +/* scatterlist table functions */ +/*********************************************/ + + +static void vb2_dc_sgt_foreach_page(struct sg_table *sgt, + void (*cb)(struct page *pg)) +{ + struct scatterlist *s; + unsigned int i; + + for_each_sg(sgt->sgl, s, sgt->orig_nents, i) { + struct page *page = sg_page(s); + unsigned int n_pages = PAGE_ALIGN(s->offset + s->length) + >> PAGE_SHIFT; + unsigned int j; + + for (j = 0; j < n_pages; ++j, ++page) + cb(page); + } +} + +static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) +{ + struct scatterlist *s; + dma_addr_t expected = sg_dma_address(sgt->sgl); + unsigned int i; + unsigned long size = 0; + + for_each_sg(sgt->sgl, s, sgt->nents, i) { + if (sg_dma_address(s) != expected) + break; + expected = sg_dma_address(s) + sg_dma_len(s); + size += sg_dma_len(s); + } + return size; +} + +/*********************************************/ +/* callbacks for all buffers */ +/*********************************************/ + +static void *vb2_dc_cookie(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return &buf->dma_addr; +} + +static void *vb2_dc_vaddr(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return buf->vaddr; +} + +static unsigned int vb2_dc_num_users(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return atomic_read(&buf->refcount); +} + +static void vb2_dc_prepare(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + /* DMABUF exporter will flush the cache for us */ + if (!sgt || buf->db_attach) + return; + + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + +static void vb2_dc_finish(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + /* DMABUF exporter will flush the cache for us */ + if (!sgt || buf->db_attach) + return; + + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + +/*********************************************/ +/* callbacks for MMAP buffers */ +/*********************************************/ + +static void vb2_dc_put(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + if (!atomic_dec_and_test(&buf->refcount)) + return; + + if (buf->sgt_base) { + sg_free_table(buf->sgt_base); + kfree(buf->sgt_base); + } + dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr); + put_device(buf->dev); + kfree(buf); +} + +static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_flags) +{ + struct vb2_dc_conf *conf = alloc_ctx; + struct device *dev = conf->dev; + struct vb2_dc_buf *buf; + + buf = kzalloc(sizeof *buf, GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, + GFP_KERNEL | gfp_flags); + if (!buf->vaddr) { + dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size); + kfree(buf); + return ERR_PTR(-ENOMEM); + } + + /* Prevent the device from being released while the buffer is used */ + buf->dev = get_device(dev); + buf->size = size; + + buf->handler.refcount = &buf->refcount; + buf->handler.put = vb2_dc_put; + buf->handler.arg = buf; + + atomic_inc(&buf->refcount); + + return buf; +} + +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,9,0)) +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) +static int +backport_vb2_mmap_pfn_range(struct vm_area_struct *vma, unsigned long paddr, + unsigned long size, + const struct vm_operations_struct *vm_ops, + void *priv) +{ + int ret; + + size = min_t(unsigned long, vma->vm_end - vma->vm_start, size); + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + ret = remap_pfn_range(vma, vma->vm_start, paddr >> PAGE_SHIFT, + size, vma->vm_page_prot); + if (ret) { + printk(KERN_ERR "Remapping memory failed, error: %d\n", ret); + return ret; + } + + vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; + vma->vm_private_data = priv; + vma->vm_ops = vm_ops; + + vma->vm_ops->open(vma); + + pr_debug("%s: mapped paddr 0x%08lx at 0x%08lx, size %ld\n", + __func__, paddr, vma->vm_start, size); + + return 0; +} + +static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) +{ + struct vb2_dc_buf *buf = buf_priv; + + if (!buf) { + printk(KERN_ERR "No buffer to map\n"); + return -EINVAL; + } + + return backport_vb2_mmap_pfn_range(vma, buf->dma_addr, buf->size, + &vb2_common_vm_ops, &buf->handler); +} +#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)) */ +#else +static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) +{ + struct vb2_dc_buf *buf = buf_priv; + int ret; + + if (!buf) { + printk(KERN_ERR "No buffer to map\n"); + return -EINVAL; + } + + /* + * dma_mmap_* uses vm_pgoff as in-buffer offset, but we want to + * map whole buffer + */ + vma->vm_pgoff = 0; + + ret = dma_mmap_coherent(buf->dev, vma, buf->vaddr, + buf->dma_addr, buf->size); + + if (ret) { + pr_err("Remapping memory failed, error: %d\n", ret); + return ret; + } + + vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; + vma->vm_private_data = &buf->handler; + vma->vm_ops = &vb2_common_vm_ops; + + vma->vm_ops->open(vma); + + pr_debug("%s: mapped dma addr 0x%08lx at 0x%08lx, size %ld\n", + __func__, (unsigned long)buf->dma_addr, vma->vm_start, + buf->size); + + return 0; +} +#endif /* (LINUX_VERSION_CODE < KERNEL_VERSION(3,9,0)) */ + +/*********************************************/ +/* DMABUF ops for exporters */ +/*********************************************/ + +struct vb2_dc_attachment { + struct sg_table sgt; + enum dma_data_direction dir; +}; + +static int vb2_dc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev, + struct dma_buf_attachment *dbuf_attach) +{ + struct vb2_dc_attachment *attach; + unsigned int i; + struct scatterlist *rd, *wr; + struct sg_table *sgt; + struct vb2_dc_buf *buf = dbuf->priv; + int ret; + + attach = kzalloc(sizeof(*attach), GFP_KERNEL); + if (!attach) + return -ENOMEM; + + sgt = &attach->sgt; + /* Copy the buf->base_sgt scatter list to the attachment, as we can't + * map the same scatter list to multiple attachments at the same time. + */ + ret = sg_alloc_table(sgt, buf->sgt_base->orig_nents, GFP_KERNEL); + if (ret) { + kfree(attach); + return -ENOMEM; + } + + rd = buf->sgt_base->sgl; + wr = sgt->sgl; + for (i = 0; i < sgt->orig_nents; ++i) { + sg_set_page(wr, sg_page(rd), rd->length, rd->offset); + rd = sg_next(rd); + wr = sg_next(wr); + } + + attach->dir = DMA_NONE; + dbuf_attach->priv = attach; + + return 0; +} + +static void vb2_dc_dmabuf_ops_detach(struct dma_buf *dbuf, + struct dma_buf_attachment *db_attach) +{ + struct vb2_dc_attachment *attach = db_attach->priv; + struct sg_table *sgt; + + if (!attach) + return; + + sgt = &attach->sgt; + + /* release the scatterlist cache */ + if (attach->dir != DMA_NONE) + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dir); + sg_free_table(sgt); + kfree(attach); + db_attach->priv = NULL; +} + +static struct sg_table *vb2_dc_dmabuf_ops_map( + struct dma_buf_attachment *db_attach, enum dma_data_direction dir) +{ + struct vb2_dc_attachment *attach = db_attach->priv; + /* stealing dmabuf mutex to serialize map/unmap operations */ + struct mutex *lock = &db_attach->dmabuf->lock; + struct sg_table *sgt; + int ret; + + mutex_lock(lock); + + sgt = &attach->sgt; + /* return previously mapped sg table */ + if (attach->dir == dir) { + mutex_unlock(lock); + return sgt; + } + + /* release any previous cache */ + if (attach->dir != DMA_NONE) { + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dir); + attach->dir = DMA_NONE; + } + + /* mapping to the client with new direction */ + ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dir); + if (ret <= 0) { + pr_err("failed to map scatterlist\n"); + mutex_unlock(lock); + return ERR_PTR(-EIO); + } + + attach->dir = dir; + + mutex_unlock(lock); + + return sgt; +} + +static void vb2_dc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, + struct sg_table *sgt, enum dma_data_direction dir) +{ + /* nothing to be done here */ +} + +static void vb2_dc_dmabuf_ops_release(struct dma_buf *dbuf) +{ + /* drop reference obtained in vb2_dc_get_dmabuf */ + vb2_dc_put(dbuf->priv); +} + +static void *vb2_dc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum) +{ + struct vb2_dc_buf *buf = dbuf->priv; + + return buf->vaddr + pgnum * PAGE_SIZE; +} + +static void *vb2_dc_dmabuf_ops_vmap(struct dma_buf *dbuf) +{ + struct vb2_dc_buf *buf = dbuf->priv; + + return buf->vaddr; +} + +static int vb2_dc_dmabuf_ops_mmap(struct dma_buf *dbuf, + struct vm_area_struct *vma) +{ + return vb2_dc_mmap(dbuf->priv, vma); +} + +static struct dma_buf_ops vb2_dc_dmabuf_ops = { + .attach = vb2_dc_dmabuf_ops_attach, + .detach = vb2_dc_dmabuf_ops_detach, + .map_dma_buf = vb2_dc_dmabuf_ops_map, + .unmap_dma_buf = vb2_dc_dmabuf_ops_unmap, + .kmap = vb2_dc_dmabuf_ops_kmap, + .kmap_atomic = vb2_dc_dmabuf_ops_kmap, + .vmap = vb2_dc_dmabuf_ops_vmap, + .mmap = vb2_dc_dmabuf_ops_mmap, + .release = vb2_dc_dmabuf_ops_release, +}; + +static struct sg_table *vb2_dc_get_base_sgt(struct vb2_dc_buf *buf) +{ + int ret; + struct sg_table *sgt; + + sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + dev_err(buf->dev, "failed to alloc sg table\n"); + return NULL; + } + + ret = dma_get_sgtable(buf->dev, sgt, buf->vaddr, buf->dma_addr, + buf->size); + if (ret < 0) { + dev_err(buf->dev, "failed to get scatterlist from DMA API\n"); + kfree(sgt); + return NULL; + } + + return sgt; +} + +static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct dma_buf *dbuf; + + if (!buf->sgt_base) + buf->sgt_base = vb2_dc_get_base_sgt(buf); + + if (WARN_ON(!buf->sgt_base)) + return NULL; + + dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, 0); + if (IS_ERR(dbuf)) + return NULL; + + /* dmabuf keeps reference to vb2 buffer */ + atomic_inc(&buf->refcount); + + return dbuf; +} + +/*********************************************/ +/* callbacks for USERPTR buffers */ +/*********************************************/ + +static inline int vma_is_io(struct vm_area_struct *vma) +{ + return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); +} + +static int vb2_dc_get_user_pages(unsigned long start, struct page **pages, + int n_pages, struct vm_area_struct *vma, int write) +{ + if (vma_is_io(vma)) { + unsigned int i; + + for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) { + unsigned long pfn; + int ret = follow_pfn(vma, start, &pfn); + + if (ret) { + pr_err("no page for address %lu\n", start); + return ret; + } + pages[i] = pfn_to_page(pfn); + } + } else { + int n; + + n = get_user_pages(current, current->mm, start & PAGE_MASK, + n_pages, write, 1, pages, NULL); + /* negative error means that no page was pinned */ + n = max(n, 0); + if (n != n_pages) { + pr_err("got only %d of %d user pages\n", n, n_pages); + while (n) + put_page(pages[--n]); + return -EFAULT; + } + } + + return 0; +} + +static void vb2_dc_put_dirty_page(struct page *page) +{ + set_page_dirty_lock(page); + put_page(page); +} + +static void vb2_dc_put_userptr(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); + if (!vma_is_io(buf->vma)) + vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page); + + sg_free_table(sgt); + kfree(sgt); + vb2_put_vma(buf->vma); + kfree(buf); +} + +static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, + unsigned long size, int write) +{ + struct vb2_dc_conf *conf = alloc_ctx; + struct vb2_dc_buf *buf; + unsigned long start; + unsigned long end; + unsigned long offset; + struct page **pages; + int n_pages; + int ret = 0; + struct vm_area_struct *vma; + struct sg_table *sgt; + unsigned long contig_size; + unsigned long dma_align = dma_get_cache_alignment(); + + /* Only cache aligned DMA transfers are reliable */ + if (!IS_ALIGNED(vaddr | size, dma_align)) { + pr_debug("user data must be aligned to %lu bytes\n", dma_align); + return ERR_PTR(-EINVAL); + } + + if (!size) { + pr_debug("size is zero\n"); + return ERR_PTR(-EINVAL); + } + + buf = kzalloc(sizeof *buf, GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->dev = conf->dev; + buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + + start = vaddr & PAGE_MASK; + offset = vaddr & ~PAGE_MASK; + end = PAGE_ALIGN(vaddr + size); + n_pages = (end - start) >> PAGE_SHIFT; + + pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + pr_err("failed to allocate pages table\n"); + goto fail_buf; + } + + /* current->mm->mmap_sem is taken by videobuf2 core */ + vma = find_vma(current->mm, vaddr); + if (!vma) { + pr_err("no vma for address %lu\n", vaddr); + ret = -EFAULT; + goto fail_pages; + } + + if (vma->vm_end < vaddr + size) { + pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size); + ret = -EFAULT; + goto fail_pages; + } + + buf->vma = vb2_get_vma(vma); + if (!buf->vma) { + pr_err("failed to copy vma\n"); + ret = -ENOMEM; + goto fail_pages; + } + + /* extract page list from userspace mapping */ + ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write); + if (ret) { + pr_err("failed to get user pages\n"); + goto fail_vma; + } + + sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + pr_err("failed to allocate sg table\n"); + ret = -ENOMEM; + goto fail_get_user_pages; + } + + ret = sg_alloc_table_from_pages(sgt, pages, n_pages, + offset, size, GFP_KERNEL); + if (ret) { + pr_err("failed to initialize sg table\n"); + goto fail_sgt; + } + + /* pages are no longer needed */ + kfree(pages); + pages = NULL; + + sgt->nents = dma_map_sg(buf->dev, sgt->sgl, sgt->orig_nents, + buf->dma_dir); + if (sgt->nents <= 0) { + pr_err("failed to map scatterlist\n"); + ret = -EIO; + goto fail_sgt_init; + } + + contig_size = vb2_dc_get_contiguous_size(sgt); + if (contig_size < size) { + pr_err("contiguous mapping is too small %lu/%lu\n", + contig_size, size); + ret = -EFAULT; + goto fail_map_sg; + } + + buf->dma_addr = sg_dma_address(sgt->sgl); + buf->size = size; + buf->dma_sgt = sgt; + + return buf; + +fail_map_sg: + dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); + +fail_sgt_init: + if (!vma_is_io(buf->vma)) + vb2_dc_sgt_foreach_page(sgt, put_page); + sg_free_table(sgt); + +fail_sgt: + kfree(sgt); + +fail_get_user_pages: + if (pages && !vma_is_io(buf->vma)) + while (n_pages) + put_page(pages[--n_pages]); + +fail_vma: + vb2_put_vma(buf->vma); + +fail_pages: + kfree(pages); /* kfree is NULL-proof */ + +fail_buf: + kfree(buf); + + return ERR_PTR(ret); +} + +/*********************************************/ +/* callbacks for DMABUF buffers */ +/*********************************************/ + +static int vb2_dc_map_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + struct sg_table *sgt; + unsigned long contig_size; + + if (WARN_ON(!buf->db_attach)) { + pr_err("trying to pin a non attached buffer\n"); + return -EINVAL; + } + + if (WARN_ON(buf->dma_sgt)) { + pr_err("dmabuf buffer is already pinned\n"); + return 0; + } + + /* get the associated scatterlist for this buffer */ + sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir); + if (IS_ERR_OR_NULL(sgt)) { + pr_err("Error getting dmabuf scatterlist\n"); + return -EINVAL; + } + + /* checking if dmabuf is big enough to store contiguous chunk */ + contig_size = vb2_dc_get_contiguous_size(sgt); + if (contig_size < buf->size) { + pr_err("contiguous chunk is too small %lu/%lu b\n", + contig_size, buf->size); + dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); + return -EFAULT; + } + + buf->dma_addr = sg_dma_address(sgt->sgl); + buf->dma_sgt = sgt; + + return 0; +} + +static void vb2_dc_unmap_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + struct sg_table *sgt = buf->dma_sgt; + + if (WARN_ON(!buf->db_attach)) { + pr_err("trying to unpin a not attached buffer\n"); + return; + } + + if (WARN_ON(!sgt)) { + pr_err("dmabuf buffer is already unpinned\n"); + return; + } + + dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); + + buf->dma_addr = 0; + buf->dma_sgt = NULL; +} + +static void vb2_dc_detach_dmabuf(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + + /* if vb2 works correctly you should never detach mapped buffer */ + if (WARN_ON(buf->dma_addr)) + vb2_dc_unmap_dmabuf(buf); + + /* detach this attachment */ + dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach); + kfree(buf); +} + +static void *vb2_dc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, + unsigned long size, int write) +{ + struct vb2_dc_conf *conf = alloc_ctx; + struct vb2_dc_buf *buf; + struct dma_buf_attachment *dba; + + if (dbuf->size < size) + return ERR_PTR(-EFAULT); + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->dev = conf->dev; + /* create attachment for the dmabuf with the user device */ + dba = dma_buf_attach(dbuf, buf->dev); + if (IS_ERR(dba)) { + pr_err("failed to attach dmabuf\n"); + kfree(buf); + return dba; + } + + buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + buf->size = size; + buf->db_attach = dba; + + return buf; +} + +/*********************************************/ +/* DMA CONTIG exported functions */ +/*********************************************/ + +const struct vb2_mem_ops vb2_dma_contig_memops = { + .alloc = vb2_dc_alloc, + .put = vb2_dc_put, + .get_dmabuf = vb2_dc_get_dmabuf, + .cookie = vb2_dc_cookie, + .vaddr = vb2_dc_vaddr, + .mmap = vb2_dc_mmap, + .get_userptr = vb2_dc_get_userptr, + .put_userptr = vb2_dc_put_userptr, + .prepare = vb2_dc_prepare, + .finish = vb2_dc_finish, + .map_dmabuf = vb2_dc_map_dmabuf, + .unmap_dmabuf = vb2_dc_unmap_dmabuf, + .attach_dmabuf = vb2_dc_attach_dmabuf, + .detach_dmabuf = vb2_dc_detach_dmabuf, + .num_users = vb2_dc_num_users, +}; +EXPORT_SYMBOL_GPL(vb2_dma_contig_memops); + +void *vb2_dma_contig_init_ctx(struct device *dev) +{ + struct vb2_dc_conf *conf; + + conf = kzalloc(sizeof *conf, GFP_KERNEL); + if (!conf) + return ERR_PTR(-ENOMEM); + + conf->dev = dev; + + return conf; +} +EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx); + +void vb2_dma_contig_cleanup_ctx(void *alloc_ctx) +{ + kfree(alloc_ctx); +} +EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx); + +MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>"); +MODULE_LICENSE("GPL"); |