diff options
Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-vmalloc.c')
-rw-r--r-- | drivers/media/common/videobuf2/videobuf2-vmalloc.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-vmalloc.c b/drivers/media/common/videobuf2/videobuf2-vmalloc.c new file mode 100644 index 000000000..948152f15 --- /dev/null +++ b/drivers/media/common/videobuf2/videobuf2-vmalloc.c @@ -0,0 +1,450 @@ +/* + * videobuf2-vmalloc.c - vmalloc 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/io.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/refcount.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +#include <media/videobuf2-v4l2.h> +#include <media/videobuf2-vmalloc.h> +#include <media/videobuf2-memops.h> + +struct vb2_vmalloc_buf { + void *vaddr; + struct frame_vector *vec; + enum dma_data_direction dma_dir; + unsigned long size; + refcount_t refcount; + struct vb2_vmarea_handler handler; + struct dma_buf *dbuf; +}; + +static void vb2_vmalloc_put(void *buf_priv); + +static void *vb2_vmalloc_alloc(struct vb2_buffer *vb, struct device *dev, + unsigned long size) +{ + struct vb2_vmalloc_buf *buf; + + buf = kzalloc(sizeof(*buf), GFP_KERNEL | vb->vb2_queue->gfp_flags); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->size = size; + buf->vaddr = vmalloc_user(buf->size); + if (!buf->vaddr) { + pr_debug("vmalloc of size %ld failed\n", buf->size); + kfree(buf); + return ERR_PTR(-ENOMEM); + } + + buf->dma_dir = vb->vb2_queue->dma_dir; + buf->handler.refcount = &buf->refcount; + buf->handler.put = vb2_vmalloc_put; + buf->handler.arg = buf; + + refcount_set(&buf->refcount, 1); + return buf; +} + +static void vb2_vmalloc_put(void *buf_priv) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + + if (refcount_dec_and_test(&buf->refcount)) { + vfree(buf->vaddr); + kfree(buf); + } +} + +static void *vb2_vmalloc_get_userptr(struct vb2_buffer *vb, struct device *dev, + unsigned long vaddr, unsigned long size) +{ + struct vb2_vmalloc_buf *buf; + struct frame_vector *vec; + int n_pages, offset, i; + int ret = -ENOMEM; + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->dma_dir = vb->vb2_queue->dma_dir; + offset = vaddr & ~PAGE_MASK; + buf->size = size; + vec = vb2_create_framevec(vaddr, size); + if (IS_ERR(vec)) { + ret = PTR_ERR(vec); + goto fail_pfnvec_create; + } + buf->vec = vec; + n_pages = frame_vector_count(vec); + if (frame_vector_to_pages(vec) < 0) { + unsigned long *nums = frame_vector_pfns(vec); + + /* + * We cannot get page pointers for these pfns. Check memory is + * physically contiguous and use direct mapping. + */ + for (i = 1; i < n_pages; i++) + if (nums[i-1] + 1 != nums[i]) + goto fail_map; + buf->vaddr = (__force void *) + ioremap(__pfn_to_phys(nums[0]), size + offset); + } else { + buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1); + } + + if (!buf->vaddr) + goto fail_map; + buf->vaddr += offset; + return buf; + +fail_map: + vb2_destroy_framevec(vec); +fail_pfnvec_create: + kfree(buf); + + return ERR_PTR(ret); +} + +static void vb2_vmalloc_put_userptr(void *buf_priv) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK; + unsigned int i; + struct page **pages; + unsigned int n_pages; + + if (!buf->vec->is_pfns) { + n_pages = frame_vector_count(buf->vec); + pages = frame_vector_pages(buf->vec); + if (vaddr) + vm_unmap_ram((void *)vaddr, n_pages); + if (buf->dma_dir == DMA_FROM_DEVICE || + buf->dma_dir == DMA_BIDIRECTIONAL) + for (i = 0; i < n_pages; i++) + set_page_dirty_lock(pages[i]); + } else { + iounmap((__force void __iomem *)buf->vaddr); + } + vb2_destroy_framevec(buf->vec); + kfree(buf); +} + +static void *vb2_vmalloc_vaddr(struct vb2_buffer *vb, void *buf_priv) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + + if (!buf->vaddr) { + pr_err("Address of an unallocated plane requested or cannot map user pointer\n"); + return NULL; + } + + return buf->vaddr; +} + +static unsigned int vb2_vmalloc_num_users(void *buf_priv) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + return refcount_read(&buf->refcount); +} + +static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + int ret; + + if (!buf) { + pr_err("No memory to map\n"); + return -EINVAL; + } + + ret = remap_vmalloc_range(vma, buf->vaddr, 0); + if (ret) { + pr_err("Remapping vmalloc memory, error: %d\n", ret); + return ret; + } + + /* + * Make sure that vm_areas for 2 buffers won't be merged together + */ + vma->vm_flags |= VM_DONTEXPAND; + + /* + * 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; +} + +#ifdef CONFIG_HAS_DMA +/*********************************************/ +/* DMABUF ops for exporters */ +/*********************************************/ + +struct vb2_vmalloc_attachment { + struct sg_table sgt; + enum dma_data_direction dma_dir; +}; + +static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, + struct dma_buf_attachment *dbuf_attach) +{ + struct vb2_vmalloc_attachment *attach; + struct vb2_vmalloc_buf *buf = dbuf->priv; + int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE; + struct sg_table *sgt; + struct scatterlist *sg; + void *vaddr = buf->vaddr; + int ret; + int i; + + attach = kzalloc(sizeof(*attach), GFP_KERNEL); + if (!attach) + return -ENOMEM; + + sgt = &attach->sgt; + ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL); + if (ret) { + kfree(attach); + return ret; + } + for_each_sgtable_sg(sgt, sg, i) { + struct page *page = vmalloc_to_page(vaddr); + + if (!page) { + sg_free_table(sgt); + kfree(attach); + return -ENOMEM; + } + sg_set_page(sg, page, PAGE_SIZE, 0); + vaddr += PAGE_SIZE; + } + + attach->dma_dir = DMA_NONE; + dbuf_attach->priv = attach; + return 0; +} + +static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf, + struct dma_buf_attachment *db_attach) +{ + struct vb2_vmalloc_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_sgtable(db_attach->dev, sgt, attach->dma_dir, 0); + sg_free_table(sgt); + kfree(attach); + db_attach->priv = NULL; +} + +static struct sg_table *vb2_vmalloc_dmabuf_ops_map( + struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir) +{ + struct vb2_vmalloc_attachment *attach = db_attach->priv; + /* stealing dmabuf mutex to serialize map/unmap operations */ + struct mutex *lock = &db_attach->dmabuf->lock; + struct sg_table *sgt; + + 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_sgtable(db_attach->dev, sgt, attach->dma_dir, 0); + attach->dma_dir = DMA_NONE; + } + + /* mapping to the client with new direction */ + if (dma_map_sgtable(db_attach->dev, sgt, dma_dir, 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_vmalloc_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_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf) +{ + /* drop reference obtained in vb2_vmalloc_get_dmabuf */ + vb2_vmalloc_put(dbuf->priv); +} + +static int vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf, + struct iosys_map *map) +{ + struct vb2_vmalloc_buf *buf = dbuf->priv; + + iosys_map_set_vaddr(map, buf->vaddr); + + return 0; +} + +static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf, + struct vm_area_struct *vma) +{ + return vb2_vmalloc_mmap(dbuf->priv, vma); +} + +static const struct dma_buf_ops vb2_vmalloc_dmabuf_ops = { + .attach = vb2_vmalloc_dmabuf_ops_attach, + .detach = vb2_vmalloc_dmabuf_ops_detach, + .map_dma_buf = vb2_vmalloc_dmabuf_ops_map, + .unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap, + .vmap = vb2_vmalloc_dmabuf_ops_vmap, + .mmap = vb2_vmalloc_dmabuf_ops_mmap, + .release = vb2_vmalloc_dmabuf_ops_release, +}; + +static struct dma_buf *vb2_vmalloc_get_dmabuf(struct vb2_buffer *vb, + void *buf_priv, + unsigned long flags) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + struct dma_buf *dbuf; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + + exp_info.ops = &vb2_vmalloc_dmabuf_ops; + exp_info.size = buf->size; + exp_info.flags = flags; + exp_info.priv = buf; + + if (WARN_ON(!buf->vaddr)) + return NULL; + + dbuf = dma_buf_export(&exp_info); + if (IS_ERR(dbuf)) + return NULL; + + /* dmabuf keeps reference to vb2 buffer */ + refcount_inc(&buf->refcount); + + return dbuf; +} +#endif /* CONFIG_HAS_DMA */ + + +/*********************************************/ +/* callbacks for DMABUF buffers */ +/*********************************************/ + +static int vb2_vmalloc_map_dmabuf(void *mem_priv) +{ + struct vb2_vmalloc_buf *buf = mem_priv; + struct iosys_map map; + int ret; + + ret = dma_buf_vmap(buf->dbuf, &map); + if (ret) + return -EFAULT; + buf->vaddr = map.vaddr; + + return 0; +} + +static void vb2_vmalloc_unmap_dmabuf(void *mem_priv) +{ + struct vb2_vmalloc_buf *buf = mem_priv; + struct iosys_map map = IOSYS_MAP_INIT_VADDR(buf->vaddr); + + dma_buf_vunmap(buf->dbuf, &map); + buf->vaddr = NULL; +} + +static void vb2_vmalloc_detach_dmabuf(void *mem_priv) +{ + struct vb2_vmalloc_buf *buf = mem_priv; + struct iosys_map map = IOSYS_MAP_INIT_VADDR(buf->vaddr); + + if (buf->vaddr) + dma_buf_vunmap(buf->dbuf, &map); + + kfree(buf); +} + +static void *vb2_vmalloc_attach_dmabuf(struct vb2_buffer *vb, + struct device *dev, + struct dma_buf *dbuf, + unsigned long size) +{ + struct vb2_vmalloc_buf *buf; + + if (dbuf->size < size) + return ERR_PTR(-EFAULT); + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->dbuf = dbuf; + buf->dma_dir = vb->vb2_queue->dma_dir; + buf->size = size; + + return buf; +} + + +const struct vb2_mem_ops vb2_vmalloc_memops = { + .alloc = vb2_vmalloc_alloc, + .put = vb2_vmalloc_put, + .get_userptr = vb2_vmalloc_get_userptr, + .put_userptr = vb2_vmalloc_put_userptr, +#ifdef CONFIG_HAS_DMA + .get_dmabuf = vb2_vmalloc_get_dmabuf, +#endif + .map_dmabuf = vb2_vmalloc_map_dmabuf, + .unmap_dmabuf = vb2_vmalloc_unmap_dmabuf, + .attach_dmabuf = vb2_vmalloc_attach_dmabuf, + .detach_dmabuf = vb2_vmalloc_detach_dmabuf, + .vaddr = vb2_vmalloc_vaddr, + .mmap = vb2_vmalloc_mmap, + .num_users = vb2_vmalloc_num_users, +}; +EXPORT_SYMBOL_GPL(vb2_vmalloc_memops); + +MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(DMA_BUF); |