From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c | 754 ++++++++++++++++++++++ 1 file changed, 754 insertions(+) create mode 100644 kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c (limited to 'kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c') diff --git a/kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c b/kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c new file mode 100644 index 000000000..45c708e46 --- /dev/null +++ b/kernel/drivers/media/v4l2-core/videobuf2-dma-sg.c @@ -0,0 +1,754 @@ +/* + * videobuf2-dma-sg.c - dma scatter/gather memory allocator for videobuf2 + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Andrzej Pietrasiewicz + * + * 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 +#include +#include +#include +#include +#include + +#include +#include +#include + +static int debug; +module_param(debug, int, 0644); + +#define dprintk(level, fmt, arg...) \ + do { \ + if (debug >= level) \ + printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg); \ + } while (0) + +struct vb2_dma_sg_conf { + struct device *dev; +}; + +struct vb2_dma_sg_buf { + struct device *dev; + void *vaddr; + struct page **pages; + int offset; + enum dma_data_direction dma_dir; + struct sg_table sg_table; + /* + * This will point to sg_table when used with the MMAP or USERPTR + * memory model, and to the dma_buf sglist when used with the + * DMABUF memory model. + */ + struct sg_table *dma_sgt; + size_t size; + unsigned int num_pages; + atomic_t refcount; + struct vb2_vmarea_handler handler; + struct vm_area_struct *vma; + + struct dma_buf_attachment *db_attach; +}; + +static void vb2_dma_sg_put(void *buf_priv); + +static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf, + gfp_t gfp_flags) +{ + unsigned int last_page = 0; + int size = buf->size; + + while (size > 0) { + struct page *pages; + int order; + int i; + + order = get_order(size); + /* Dont over allocate*/ + if ((PAGE_SIZE << order) > size) + order--; + + pages = NULL; + while (!pages) { + pages = alloc_pages(GFP_KERNEL | __GFP_ZERO | + __GFP_NOWARN | gfp_flags, order); + if (pages) + break; + + if (order == 0) { + while (last_page--) + __free_page(buf->pages[last_page]); + return -ENOMEM; + } + order--; + } + + split_page(pages, order); + for (i = 0; i < (1 << order); i++) + buf->pages[last_page++] = &pages[i]; + + size -= PAGE_SIZE << order; + } + + return 0; +} + +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); + + dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); + + 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. + */ + if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents, + buf->dma_dir, &attrs) == 0) + 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; +} + +static void vb2_dma_sg_put(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + struct sg_table *sgt = &buf->sg_table; + int i = buf->num_pages; + + if (atomic_dec_and_test(&buf->refcount)) { + DEFINE_DMA_ATTRS(attrs); + + dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); + dprintk(1, "%s: Freeing buffer of %d pages\n", __func__, + buf->num_pages); + dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents, + buf->dma_dir, &attrs); + if (buf->vaddr) + vm_unmap_ram(buf->vaddr, buf->num_pages); + sg_free_table(buf->dma_sgt); + while (--i >= 0) + __free_page(buf->pages[i]); + kfree(buf->pages); + put_device(buf->dev); + kfree(buf); + } +} + +static void vb2_dma_sg_prepare(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + /* DMABUF exporter will flush the cache for us */ + if (buf->db_attach) + return; + + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + +static void vb2_dma_sg_finish(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + struct sg_table *sgt = buf->dma_sgt; + + /* DMABUF exporter will flush the cache for us */ + if (buf->db_attach) + return; + + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); +} + +static inline int vma_is_io(struct vm_area_struct *vma) +{ + return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); +} + +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); + + 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; + + 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. + */ + if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents, + buf->dma_dir, &attrs) == 0) + 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; +} + +/* + * @put_userptr: inform the allocator that a USERPTR buffer will no longer + * be used + */ +static void vb2_dma_sg_put_userptr(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + struct sg_table *sgt = &buf->sg_table; + int i = buf->num_pages; + DEFINE_DMA_ATTRS(attrs); + + dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); + + dprintk(1, "%s: Releasing userspace buffer of %d pages\n", + __func__, buf->num_pages); + dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir, &attrs); + if (buf->vaddr) + vm_unmap_ram(buf->vaddr, buf->num_pages); + sg_free_table(buf->dma_sgt); + while (--i >= 0) { + if (buf->dma_dir == DMA_FROM_DEVICE) + set_page_dirty_lock(buf->pages[i]); + if (!vma_is_io(buf->vma)) + put_page(buf->pages[i]); + } + kfree(buf->pages); + vb2_put_vma(buf->vma); + kfree(buf); +} + +static void *vb2_dma_sg_vaddr(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + + BUG_ON(!buf); + + if (!buf->vaddr) { + if (buf->db_attach) + buf->vaddr = dma_buf_vmap(buf->db_attach->dmabuf); + else + buf->vaddr = vm_map_ram(buf->pages, + buf->num_pages, -1, PAGE_KERNEL); + } + + /* add offset in case userptr is not page-aligned */ + return buf->vaddr ? buf->vaddr + buf->offset : NULL; +} + +static unsigned int vb2_dma_sg_num_users(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + + return atomic_read(&buf->refcount); +} + +static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + unsigned long uaddr = vma->vm_start; + unsigned long usize = vma->vm_end - vma->vm_start; + int i = 0; + + if (!buf) { + printk(KERN_ERR "No memory to map\n"); + return -EINVAL; + } + + do { + int ret; + + ret = vm_insert_page(vma, uaddr, buf->pages[i++]); + if (ret) { + printk(KERN_ERR "Remapping memory, error: %d\n", ret); + return ret; + } + + uaddr += PAGE_SIZE; + usize -= PAGE_SIZE; + } while (usize > 0); + + + /* + * Use common vm_area operations to track buffer refcount. + */ + vma->vm_private_data = &buf->handler; + vma->vm_ops = &vb2_common_vm_ops; + + vma->vm_ops->open(vma); + + return 0; +} + +/*********************************************/ +/* DMABUF ops for exporters */ +/*********************************************/ + +struct vb2_dma_sg_attachment { + struct sg_table sgt; + enum dma_data_direction dma_dir; +}; + +static int vb2_dma_sg_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev, + struct dma_buf_attachment *dbuf_attach) +{ + struct vb2_dma_sg_attachment *attach; + unsigned int i; + struct scatterlist *rd, *wr; + struct sg_table *sgt; + struct vb2_dma_sg_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->dma_sgt->orig_nents, GFP_KERNEL); + if (ret) { + kfree(attach); + return -ENOMEM; + } + + rd = buf->dma_sgt->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->dma_dir = DMA_NONE; + dbuf_attach->priv = attach; + + return 0; +} + +static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf, + struct dma_buf_attachment *db_attach) +{ + struct vb2_dma_sg_attachment *attach = db_attach->priv; + struct sg_table *sgt; + + if (!attach) + return; + + sgt = &attach->sgt; + + /* release the scatterlist cache */ + if (attach->dma_dir != DMA_NONE) + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dma_dir); + sg_free_table(sgt); + kfree(attach); + db_attach->priv = NULL; +} + +static struct sg_table *vb2_dma_sg_dmabuf_ops_map( + struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir) +{ + struct vb2_dma_sg_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->dma_dir == dma_dir) { + mutex_unlock(lock); + return sgt; + } + + /* release any previous cache */ + if (attach->dma_dir != DMA_NONE) { + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dma_dir); + attach->dma_dir = DMA_NONE; + } + + /* mapping to the client with new direction */ + ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dma_dir); + if (ret <= 0) { + pr_err("failed to map scatterlist\n"); + mutex_unlock(lock); + return ERR_PTR(-EIO); + } + + attach->dma_dir = dma_dir; + + mutex_unlock(lock); + + return sgt; +} + +static void vb2_dma_sg_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, + struct sg_table *sgt, enum dma_data_direction dma_dir) +{ + /* nothing to be done here */ +} + +static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf) +{ + /* drop reference obtained in vb2_dma_sg_get_dmabuf */ + vb2_dma_sg_put(dbuf->priv); +} + +static void *vb2_dma_sg_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum) +{ + struct vb2_dma_sg_buf *buf = dbuf->priv; + + return buf->vaddr ? buf->vaddr + pgnum * PAGE_SIZE : NULL; +} + +static void *vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf) +{ + struct vb2_dma_sg_buf *buf = dbuf->priv; + + return vb2_dma_sg_vaddr(buf); +} + +static int vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf *dbuf, + struct vm_area_struct *vma) +{ + return vb2_dma_sg_mmap(dbuf->priv, vma); +} + +static struct dma_buf_ops vb2_dma_sg_dmabuf_ops = { + .attach = vb2_dma_sg_dmabuf_ops_attach, + .detach = vb2_dma_sg_dmabuf_ops_detach, + .map_dma_buf = vb2_dma_sg_dmabuf_ops_map, + .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap, + .kmap = vb2_dma_sg_dmabuf_ops_kmap, + .kmap_atomic = vb2_dma_sg_dmabuf_ops_kmap, + .vmap = vb2_dma_sg_dmabuf_ops_vmap, + .mmap = vb2_dma_sg_dmabuf_ops_mmap, + .release = vb2_dma_sg_dmabuf_ops_release, +}; + +static struct dma_buf *vb2_dma_sg_get_dmabuf(void *buf_priv, unsigned long flags) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + struct dma_buf *dbuf; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + + exp_info.ops = &vb2_dma_sg_dmabuf_ops; + exp_info.size = buf->size; + exp_info.flags = flags; + exp_info.priv = buf; + + if (WARN_ON(!buf->dma_sgt)) + return NULL; + + dbuf = dma_buf_export(&exp_info); + if (IS_ERR(dbuf)) + return NULL; + + /* dmabuf keeps reference to vb2 buffer */ + atomic_inc(&buf->refcount); + + return dbuf; +} + +/*********************************************/ +/* callbacks for DMABUF buffers */ +/*********************************************/ + +static int vb2_dma_sg_map_dmabuf(void *mem_priv) +{ + struct vb2_dma_sg_buf *buf = mem_priv; + struct sg_table *sgt; + + 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(sgt)) { + pr_err("Error getting dmabuf scatterlist\n"); + return -EINVAL; + } + + buf->dma_sgt = sgt; + buf->vaddr = NULL; + + return 0; +} + +static void vb2_dma_sg_unmap_dmabuf(void *mem_priv) +{ + struct vb2_dma_sg_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; + } + + if (buf->vaddr) { + dma_buf_vunmap(buf->db_attach->dmabuf, buf->vaddr); + buf->vaddr = NULL; + } + dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); + + buf->dma_sgt = NULL; +} + +static void vb2_dma_sg_detach_dmabuf(void *mem_priv) +{ + struct vb2_dma_sg_buf *buf = mem_priv; + + /* if vb2 works correctly you should never detach mapped buffer */ + if (WARN_ON(buf->dma_sgt)) + vb2_dma_sg_unmap_dmabuf(buf); + + /* detach this attachment */ + dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach); + kfree(buf); +} + +static void *vb2_dma_sg_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, + unsigned long size, enum dma_data_direction dma_dir) +{ + struct vb2_dma_sg_conf *conf = alloc_ctx; + struct vb2_dma_sg_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 = dma_dir; + buf->size = size; + buf->db_attach = dba; + + return buf; +} + +static void *vb2_dma_sg_cookie(void *buf_priv) +{ + struct vb2_dma_sg_buf *buf = buf_priv; + + return buf->dma_sgt; +} + +const struct vb2_mem_ops vb2_dma_sg_memops = { + .alloc = vb2_dma_sg_alloc, + .put = vb2_dma_sg_put, + .get_userptr = vb2_dma_sg_get_userptr, + .put_userptr = vb2_dma_sg_put_userptr, + .prepare = vb2_dma_sg_prepare, + .finish = vb2_dma_sg_finish, + .vaddr = vb2_dma_sg_vaddr, + .mmap = vb2_dma_sg_mmap, + .num_users = vb2_dma_sg_num_users, + .get_dmabuf = vb2_dma_sg_get_dmabuf, + .map_dmabuf = vb2_dma_sg_map_dmabuf, + .unmap_dmabuf = vb2_dma_sg_unmap_dmabuf, + .attach_dmabuf = vb2_dma_sg_attach_dmabuf, + .detach_dmabuf = vb2_dma_sg_detach_dmabuf, + .cookie = vb2_dma_sg_cookie, +}; +EXPORT_SYMBOL_GPL(vb2_dma_sg_memops); + +void *vb2_dma_sg_init_ctx(struct device *dev) +{ + struct vb2_dma_sg_conf *conf; + + conf = kzalloc(sizeof(*conf), GFP_KERNEL); + if (!conf) + return ERR_PTR(-ENOMEM); + + conf->dev = dev; + + return conf; +} +EXPORT_SYMBOL_GPL(vb2_dma_sg_init_ctx); + +void vb2_dma_sg_cleanup_ctx(void *alloc_ctx) +{ + if (!IS_ERR_OR_NULL(alloc_ctx)) + kfree(alloc_ctx); +} +EXPORT_SYMBOL_GPL(vb2_dma_sg_cleanup_ctx); + +MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2"); +MODULE_AUTHOR("Andrzej Pietrasiewicz"); +MODULE_LICENSE("GPL"); -- cgit 1.2.3-korg