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path: root/drivers/media/video/videobuf2-dma-sg.c
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Diffstat (limited to 'drivers/media/video/videobuf2-dma-sg.c')
-rw-r--r--drivers/media/video/videobuf2-dma-sg.c283
1 files changed, 0 insertions, 283 deletions
diff --git a/drivers/media/video/videobuf2-dma-sg.c b/drivers/media/video/videobuf2-dma-sg.c
deleted file mode 100644
index 25c3b360e1ad..000000000000
--- a/drivers/media/video/videobuf2-dma-sg.c
+++ /dev/null
@@ -1,283 +0,0 @@
-/*
- * videobuf2-dma-sg.c - dma scatter/gather memory allocator for videobuf2
- *
- * Copyright (C) 2010 Samsung Electronics
- *
- * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.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/module.h>
-#include <linux/mm.h>
-#include <linux/scatterlist.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-
-#include <media/videobuf2-core.h>
-#include <media/videobuf2-memops.h>
-#include <media/videobuf2-dma-sg.h>
-
-struct vb2_dma_sg_buf {
- void *vaddr;
- struct page **pages;
- int write;
- int offset;
- struct vb2_dma_sg_desc sg_desc;
- atomic_t refcount;
- struct vb2_vmarea_handler handler;
-};
-
-static void vb2_dma_sg_put(void *buf_priv);
-
-static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size)
-{
- struct vb2_dma_sg_buf *buf;
- int i;
-
- buf = kzalloc(sizeof *buf, GFP_KERNEL);
- if (!buf)
- return NULL;
-
- buf->vaddr = NULL;
- buf->write = 0;
- buf->offset = 0;
- buf->sg_desc.size = size;
- buf->sg_desc.num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
-
- buf->sg_desc.sglist = vzalloc(buf->sg_desc.num_pages *
- sizeof(*buf->sg_desc.sglist));
- if (!buf->sg_desc.sglist)
- goto fail_sglist_alloc;
- sg_init_table(buf->sg_desc.sglist, buf->sg_desc.num_pages);
-
- buf->pages = kzalloc(buf->sg_desc.num_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto fail_pages_array_alloc;
-
- for (i = 0; i < buf->sg_desc.num_pages; ++i) {
- buf->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN);
- if (NULL == buf->pages[i])
- goto fail_pages_alloc;
- sg_set_page(&buf->sg_desc.sglist[i],
- buf->pages[i], PAGE_SIZE, 0);
- }
-
- buf->handler.refcount = &buf->refcount;
- buf->handler.put = vb2_dma_sg_put;
- buf->handler.arg = buf;
-
- atomic_inc(&buf->refcount);
-
- printk(KERN_DEBUG "%s: Allocated buffer of %d pages\n",
- __func__, buf->sg_desc.num_pages);
- return buf;
-
-fail_pages_alloc:
- while (--i >= 0)
- __free_page(buf->pages[i]);
- kfree(buf->pages);
-
-fail_pages_array_alloc:
- vfree(buf->sg_desc.sglist);
-
-fail_sglist_alloc:
- kfree(buf);
- return NULL;
-}
-
-static void vb2_dma_sg_put(void *buf_priv)
-{
- struct vb2_dma_sg_buf *buf = buf_priv;
- int i = buf->sg_desc.num_pages;
-
- if (atomic_dec_and_test(&buf->refcount)) {
- printk(KERN_DEBUG "%s: Freeing buffer of %d pages\n", __func__,
- buf->sg_desc.num_pages);
- if (buf->vaddr)
- vm_unmap_ram(buf->vaddr, buf->sg_desc.num_pages);
- vfree(buf->sg_desc.sglist);
- while (--i >= 0)
- __free_page(buf->pages[i]);
- kfree(buf->pages);
- kfree(buf);
- }
-}
-
-static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
- unsigned long size, int write)
-{
- struct vb2_dma_sg_buf *buf;
- unsigned long first, last;
- int num_pages_from_user, i;
-
- buf = kzalloc(sizeof *buf, GFP_KERNEL);
- if (!buf)
- return NULL;
-
- buf->vaddr = NULL;
- buf->write = write;
- buf->offset = vaddr & ~PAGE_MASK;
- buf->sg_desc.size = size;
-
- first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
- last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
- buf->sg_desc.num_pages = last - first + 1;
-
- buf->sg_desc.sglist = vzalloc(
- buf->sg_desc.num_pages * sizeof(*buf->sg_desc.sglist));
- if (!buf->sg_desc.sglist)
- goto userptr_fail_sglist_alloc;
-
- sg_init_table(buf->sg_desc.sglist, buf->sg_desc.num_pages);
-
- buf->pages = kzalloc(buf->sg_desc.num_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto userptr_fail_pages_array_alloc;
-
- num_pages_from_user = get_user_pages(current, current->mm,
- vaddr & PAGE_MASK,
- buf->sg_desc.num_pages,
- write,
- 1, /* force */
- buf->pages,
- NULL);
-
- if (num_pages_from_user != buf->sg_desc.num_pages)
- goto userptr_fail_get_user_pages;
-
- sg_set_page(&buf->sg_desc.sglist[0], buf->pages[0],
- PAGE_SIZE - buf->offset, buf->offset);
- size -= PAGE_SIZE - buf->offset;
- for (i = 1; i < buf->sg_desc.num_pages; ++i) {
- sg_set_page(&buf->sg_desc.sglist[i], buf->pages[i],
- min_t(size_t, PAGE_SIZE, size), 0);
- size -= min_t(size_t, PAGE_SIZE, size);
- }
- return buf;
-
-userptr_fail_get_user_pages:
- printk(KERN_DEBUG "get_user_pages requested/got: %d/%d]\n",
- num_pages_from_user, buf->sg_desc.num_pages);
- while (--num_pages_from_user >= 0)
- put_page(buf->pages[num_pages_from_user]);
- kfree(buf->pages);
-
-userptr_fail_pages_array_alloc:
- vfree(buf->sg_desc.sglist);
-
-userptr_fail_sglist_alloc:
- 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;
- int i = buf->sg_desc.num_pages;
-
- printk(KERN_DEBUG "%s: Releasing userspace buffer of %d pages\n",
- __func__, buf->sg_desc.num_pages);
- if (buf->vaddr)
- vm_unmap_ram(buf->vaddr, buf->sg_desc.num_pages);
- while (--i >= 0) {
- if (buf->write)
- set_page_dirty_lock(buf->pages[i]);
- put_page(buf->pages[i]);
- }
- vfree(buf->sg_desc.sglist);
- kfree(buf->pages);
- 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)
- buf->vaddr = vm_map_ram(buf->pages,
- buf->sg_desc.num_pages,
- -1,
- PAGE_KERNEL);
-
- /* add offset in case userptr is not page-aligned */
- return buf->vaddr + buf->offset;
-}
-
-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;
-}
-
-static void *vb2_dma_sg_cookie(void *buf_priv)
-{
- struct vb2_dma_sg_buf *buf = buf_priv;
-
- return &buf->sg_desc;
-}
-
-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,
- .vaddr = vb2_dma_sg_vaddr,
- .mmap = vb2_dma_sg_mmap,
- .num_users = vb2_dma_sg_num_users,
- .cookie = vb2_dma_sg_cookie,
-};
-EXPORT_SYMBOL_GPL(vb2_dma_sg_memops);
-
-MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2");
-MODULE_AUTHOR("Andrzej Pietrasiewicz");
-MODULE_LICENSE("GPL");