![Sumit Semwal](/assets/img/avatar_default.png)
At present, dma_buf_export() takes a series of parameters, which makes it difficult to add any new parameters for exporters, if required. Make it simpler by moving all these parameters into a struct, and pass the struct * as parameter to dma_buf_export(). While at it, unite dma_buf_export_named() with dma_buf_export(), and change all callers accordingly. Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Acked-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Acked-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
755 lines
18 KiB
C
755 lines
18 KiB
C
/*
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* videobuf2-dma-sg.c - dma scatter/gather memory allocator for videobuf2
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*
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* Copyright (C) 2010 Samsung Electronics
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*
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* Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/scatterlist.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <media/videobuf2-core.h>
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#include <media/videobuf2-memops.h>
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#include <media/videobuf2-dma-sg.h>
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static int debug;
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module_param(debug, int, 0644);
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#define dprintk(level, fmt, arg...) \
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do { \
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if (debug >= level) \
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printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg); \
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} while (0)
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struct vb2_dma_sg_conf {
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struct device *dev;
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};
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struct vb2_dma_sg_buf {
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struct device *dev;
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void *vaddr;
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struct page **pages;
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int offset;
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enum dma_data_direction dma_dir;
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struct sg_table sg_table;
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/*
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* This will point to sg_table when used with the MMAP or USERPTR
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* memory model, and to the dma_buf sglist when used with the
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* DMABUF memory model.
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*/
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struct sg_table *dma_sgt;
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size_t size;
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unsigned int num_pages;
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atomic_t refcount;
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struct vb2_vmarea_handler handler;
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struct vm_area_struct *vma;
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struct dma_buf_attachment *db_attach;
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};
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static void vb2_dma_sg_put(void *buf_priv);
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static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf,
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gfp_t gfp_flags)
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{
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unsigned int last_page = 0;
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int size = buf->size;
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while (size > 0) {
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struct page *pages;
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int order;
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int i;
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order = get_order(size);
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/* Dont over allocate*/
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if ((PAGE_SIZE << order) > size)
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order--;
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pages = NULL;
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while (!pages) {
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pages = alloc_pages(GFP_KERNEL | __GFP_ZERO |
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__GFP_NOWARN | gfp_flags, order);
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if (pages)
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break;
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if (order == 0) {
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while (last_page--)
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__free_page(buf->pages[last_page]);
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return -ENOMEM;
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}
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order--;
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}
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split_page(pages, order);
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for (i = 0; i < (1 << order); i++)
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buf->pages[last_page++] = &pages[i];
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size -= PAGE_SIZE << order;
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}
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return 0;
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}
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static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size,
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enum dma_data_direction dma_dir, gfp_t gfp_flags)
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{
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struct vb2_dma_sg_conf *conf = alloc_ctx;
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struct vb2_dma_sg_buf *buf;
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struct sg_table *sgt;
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int ret;
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int num_pages;
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DEFINE_DMA_ATTRS(attrs);
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dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
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if (WARN_ON(alloc_ctx == NULL))
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return NULL;
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buf = kzalloc(sizeof *buf, GFP_KERNEL);
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if (!buf)
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return NULL;
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buf->vaddr = NULL;
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buf->dma_dir = dma_dir;
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buf->offset = 0;
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buf->size = size;
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/* size is already page aligned */
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buf->num_pages = size >> PAGE_SHIFT;
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buf->dma_sgt = &buf->sg_table;
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buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
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GFP_KERNEL);
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if (!buf->pages)
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goto fail_pages_array_alloc;
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ret = vb2_dma_sg_alloc_compacted(buf, gfp_flags);
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if (ret)
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goto fail_pages_alloc;
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ret = sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
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buf->num_pages, 0, size, GFP_KERNEL);
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if (ret)
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goto fail_table_alloc;
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/* Prevent the device from being released while the buffer is used */
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buf->dev = get_device(conf->dev);
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sgt = &buf->sg_table;
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/*
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* No need to sync to the device, this will happen later when the
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* prepare() memop is called.
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*/
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if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents,
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buf->dma_dir, &attrs) == 0)
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goto fail_map;
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buf->handler.refcount = &buf->refcount;
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buf->handler.put = vb2_dma_sg_put;
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buf->handler.arg = buf;
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atomic_inc(&buf->refcount);
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dprintk(1, "%s: Allocated buffer of %d pages\n",
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__func__, buf->num_pages);
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return buf;
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fail_map:
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put_device(buf->dev);
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sg_free_table(buf->dma_sgt);
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fail_table_alloc:
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num_pages = buf->num_pages;
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while (num_pages--)
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__free_page(buf->pages[num_pages]);
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fail_pages_alloc:
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kfree(buf->pages);
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fail_pages_array_alloc:
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kfree(buf);
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return NULL;
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}
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static void vb2_dma_sg_put(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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struct sg_table *sgt = &buf->sg_table;
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int i = buf->num_pages;
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if (atomic_dec_and_test(&buf->refcount)) {
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DEFINE_DMA_ATTRS(attrs);
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dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
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dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
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buf->num_pages);
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dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents,
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buf->dma_dir, &attrs);
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if (buf->vaddr)
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vm_unmap_ram(buf->vaddr, buf->num_pages);
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sg_free_table(buf->dma_sgt);
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while (--i >= 0)
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__free_page(buf->pages[i]);
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kfree(buf->pages);
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put_device(buf->dev);
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kfree(buf);
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}
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}
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static void vb2_dma_sg_prepare(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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struct sg_table *sgt = buf->dma_sgt;
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/* DMABUF exporter will flush the cache for us */
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if (buf->db_attach)
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return;
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dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
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}
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static void vb2_dma_sg_finish(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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struct sg_table *sgt = buf->dma_sgt;
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/* DMABUF exporter will flush the cache for us */
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if (buf->db_attach)
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return;
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dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
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}
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static inline int vma_is_io(struct vm_area_struct *vma)
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{
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return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
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}
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static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
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unsigned long size,
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enum dma_data_direction dma_dir)
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{
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struct vb2_dma_sg_conf *conf = alloc_ctx;
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struct vb2_dma_sg_buf *buf;
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unsigned long first, last;
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int num_pages_from_user;
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struct vm_area_struct *vma;
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struct sg_table *sgt;
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DEFINE_DMA_ATTRS(attrs);
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dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
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buf = kzalloc(sizeof *buf, GFP_KERNEL);
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if (!buf)
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return NULL;
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buf->vaddr = NULL;
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buf->dev = conf->dev;
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buf->dma_dir = dma_dir;
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buf->offset = vaddr & ~PAGE_MASK;
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buf->size = size;
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buf->dma_sgt = &buf->sg_table;
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first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
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last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
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buf->num_pages = last - first + 1;
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buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
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GFP_KERNEL);
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if (!buf->pages)
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goto userptr_fail_alloc_pages;
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vma = find_vma(current->mm, vaddr);
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if (!vma) {
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dprintk(1, "no vma for address %lu\n", vaddr);
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goto userptr_fail_find_vma;
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}
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if (vma->vm_end < vaddr + size) {
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dprintk(1, "vma at %lu is too small for %lu bytes\n",
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vaddr, size);
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goto userptr_fail_find_vma;
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}
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buf->vma = vb2_get_vma(vma);
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if (!buf->vma) {
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dprintk(1, "failed to copy vma\n");
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goto userptr_fail_find_vma;
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}
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if (vma_is_io(buf->vma)) {
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for (num_pages_from_user = 0;
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num_pages_from_user < buf->num_pages;
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++num_pages_from_user, vaddr += PAGE_SIZE) {
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unsigned long pfn;
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if (follow_pfn(vma, vaddr, &pfn)) {
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dprintk(1, "no page for address %lu\n", vaddr);
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break;
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}
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buf->pages[num_pages_from_user] = pfn_to_page(pfn);
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}
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} else
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num_pages_from_user = get_user_pages(current, current->mm,
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vaddr & PAGE_MASK,
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buf->num_pages,
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buf->dma_dir == DMA_FROM_DEVICE,
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1, /* force */
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buf->pages,
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NULL);
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if (num_pages_from_user != buf->num_pages)
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goto userptr_fail_get_user_pages;
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if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
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buf->num_pages, buf->offset, size, 0))
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goto userptr_fail_alloc_table_from_pages;
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sgt = &buf->sg_table;
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/*
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* No need to sync to the device, this will happen later when the
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* prepare() memop is called.
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*/
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if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents,
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buf->dma_dir, &attrs) == 0)
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goto userptr_fail_map;
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return buf;
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userptr_fail_map:
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sg_free_table(&buf->sg_table);
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userptr_fail_alloc_table_from_pages:
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userptr_fail_get_user_pages:
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dprintk(1, "get_user_pages requested/got: %d/%d]\n",
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buf->num_pages, num_pages_from_user);
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if (!vma_is_io(buf->vma))
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while (--num_pages_from_user >= 0)
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put_page(buf->pages[num_pages_from_user]);
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vb2_put_vma(buf->vma);
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userptr_fail_find_vma:
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kfree(buf->pages);
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userptr_fail_alloc_pages:
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kfree(buf);
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return NULL;
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}
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/*
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* @put_userptr: inform the allocator that a USERPTR buffer will no longer
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* be used
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*/
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static void vb2_dma_sg_put_userptr(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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struct sg_table *sgt = &buf->sg_table;
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int i = buf->num_pages;
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DEFINE_DMA_ATTRS(attrs);
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dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
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dprintk(1, "%s: Releasing userspace buffer of %d pages\n",
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__func__, buf->num_pages);
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dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir, &attrs);
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if (buf->vaddr)
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vm_unmap_ram(buf->vaddr, buf->num_pages);
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sg_free_table(buf->dma_sgt);
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while (--i >= 0) {
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if (buf->dma_dir == DMA_FROM_DEVICE)
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set_page_dirty_lock(buf->pages[i]);
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if (!vma_is_io(buf->vma))
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put_page(buf->pages[i]);
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}
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kfree(buf->pages);
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vb2_put_vma(buf->vma);
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kfree(buf);
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}
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static void *vb2_dma_sg_vaddr(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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BUG_ON(!buf);
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if (!buf->vaddr) {
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if (buf->db_attach)
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buf->vaddr = dma_buf_vmap(buf->db_attach->dmabuf);
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else
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buf->vaddr = vm_map_ram(buf->pages,
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buf->num_pages, -1, PAGE_KERNEL);
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}
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/* add offset in case userptr is not page-aligned */
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return buf->vaddr ? buf->vaddr + buf->offset : NULL;
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}
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static unsigned int vb2_dma_sg_num_users(void *buf_priv)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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return atomic_read(&buf->refcount);
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}
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static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma)
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{
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struct vb2_dma_sg_buf *buf = buf_priv;
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unsigned long uaddr = vma->vm_start;
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unsigned long usize = vma->vm_end - vma->vm_start;
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int i = 0;
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if (!buf) {
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printk(KERN_ERR "No memory to map\n");
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return -EINVAL;
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}
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do {
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int ret;
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ret = vm_insert_page(vma, uaddr, buf->pages[i++]);
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if (ret) {
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printk(KERN_ERR "Remapping memory, error: %d\n", ret);
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return ret;
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}
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uaddr += PAGE_SIZE;
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usize -= PAGE_SIZE;
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} while (usize > 0);
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/*
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* Use common vm_area operations to track buffer refcount.
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*/
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vma->vm_private_data = &buf->handler;
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vma->vm_ops = &vb2_common_vm_ops;
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vma->vm_ops->open(vma);
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return 0;
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}
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/*********************************************/
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/* DMABUF ops for exporters */
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/*********************************************/
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struct vb2_dma_sg_attachment {
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struct sg_table sgt;
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enum dma_data_direction dma_dir;
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};
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static int vb2_dma_sg_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
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struct dma_buf_attachment *dbuf_attach)
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{
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struct vb2_dma_sg_attachment *attach;
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unsigned int i;
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struct scatterlist *rd, *wr;
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struct sg_table *sgt;
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struct vb2_dma_sg_buf *buf = dbuf->priv;
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int ret;
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attach = kzalloc(sizeof(*attach), GFP_KERNEL);
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if (!attach)
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return -ENOMEM;
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sgt = &attach->sgt;
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/* Copy the buf->base_sgt scatter list to the attachment, as we can't
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* map the same scatter list to multiple attachments at the same time.
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*/
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ret = sg_alloc_table(sgt, buf->dma_sgt->orig_nents, GFP_KERNEL);
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if (ret) {
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kfree(attach);
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return -ENOMEM;
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}
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rd = buf->dma_sgt->sgl;
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wr = sgt->sgl;
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for (i = 0; i < sgt->orig_nents; ++i) {
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sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
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rd = sg_next(rd);
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wr = sg_next(wr);
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}
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attach->dma_dir = DMA_NONE;
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dbuf_attach->priv = attach;
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return 0;
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}
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static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf,
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struct dma_buf_attachment *db_attach)
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{
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struct vb2_dma_sg_attachment *attach = db_attach->priv;
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struct sg_table *sgt;
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if (!attach)
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return;
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sgt = &attach->sgt;
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/* release the scatterlist cache */
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if (attach->dma_dir != DMA_NONE)
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dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
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attach->dma_dir);
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sg_free_table(sgt);
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kfree(attach);
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db_attach->priv = NULL;
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}
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static struct sg_table *vb2_dma_sg_dmabuf_ops_map(
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struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
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{
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struct vb2_dma_sg_attachment *attach = db_attach->priv;
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/* 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");
|