From 570d2a48b700948e2ee0cadb184942ce426ae577 Mon Sep 17 00:00:00 2001 From: Javier Martin Date: Thu, 16 Feb 2012 12:19:08 -0300 Subject: [PATCH] [media] media: vb2: support userptr for PFN mappings Some video devices need to use contiguous memory which is not backed by pages as it happens with vmalloc. This patch provides USERPTR handling for those devices. Signed-off-by: Javier Martin Signed-off-by: Marek Szyprowski Signed-off-by: Sylwester Nawrocki Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/videobuf2-vmalloc.c | 70 +++++++++++++++++-------- 1 file changed, 47 insertions(+), 23 deletions(-) diff --git a/drivers/media/video/videobuf2-vmalloc.c b/drivers/media/video/videobuf2-vmalloc.c index 4e789a178f8a..6b5ca6c70a46 100644 --- a/drivers/media/video/videobuf2-vmalloc.c +++ b/drivers/media/video/videobuf2-vmalloc.c @@ -10,6 +10,7 @@ * the Free Software Foundation. */ +#include #include #include #include @@ -22,6 +23,7 @@ struct vb2_vmalloc_buf { void *vaddr; struct page **pages; + struct vm_area_struct *vma; int write; unsigned long size; unsigned int n_pages; @@ -71,6 +73,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, struct vb2_vmalloc_buf *buf; unsigned long first, last; int n_pages, offset; + struct vm_area_struct *vma; + dma_addr_t physp; buf = kzalloc(sizeof(*buf), GFP_KERNEL); if (!buf) @@ -80,23 +84,37 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, offset = vaddr & ~PAGE_MASK; buf->size = size; - first = vaddr >> PAGE_SHIFT; - last = (vaddr + size - 1) >> PAGE_SHIFT; - buf->n_pages = last - first + 1; - buf->pages = kzalloc(buf->n_pages * sizeof(struct page *), GFP_KERNEL); - if (!buf->pages) - goto fail_pages_array_alloc; - /* current->mm->mmap_sem is taken by videobuf2 core */ - n_pages = get_user_pages(current, current->mm, vaddr & PAGE_MASK, - buf->n_pages, write, 1, /* force */ - buf->pages, NULL); - if (n_pages != buf->n_pages) - goto fail_get_user_pages; - - buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1, PAGE_KERNEL); - if (!buf->vaddr) - goto fail_get_user_pages; + vma = find_vma(current->mm, vaddr); + if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) { + if (vb2_get_contig_userptr(vaddr, size, &vma, &physp)) + goto fail_pages_array_alloc; + buf->vma = vma; + buf->vaddr = ioremap_nocache(physp, size); + if (!buf->vaddr) + goto fail_pages_array_alloc; + } else { + first = vaddr >> PAGE_SHIFT; + last = (vaddr + size - 1) >> PAGE_SHIFT; + buf->n_pages = last - first + 1; + buf->pages = kzalloc(buf->n_pages * sizeof(struct page *), + GFP_KERNEL); + if (!buf->pages) + goto fail_pages_array_alloc; + + /* current->mm->mmap_sem is taken by videobuf2 core */ + n_pages = get_user_pages(current, current->mm, + vaddr & PAGE_MASK, buf->n_pages, + write, 1, /* force */ + buf->pages, NULL); + if (n_pages != buf->n_pages) + goto fail_get_user_pages; + + buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1, + PAGE_KERNEL); + if (!buf->vaddr) + goto fail_get_user_pages; + } buf->vaddr += offset; return buf; @@ -120,14 +138,20 @@ static void vb2_vmalloc_put_userptr(void *buf_priv) unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK; unsigned int i; - if (vaddr) - vm_unmap_ram((void *)vaddr, buf->n_pages); - for (i = 0; i < buf->n_pages; ++i) { - if (buf->write) - set_page_dirty_lock(buf->pages[i]); - put_page(buf->pages[i]); + if (buf->pages) { + if (vaddr) + vm_unmap_ram((void *)vaddr, buf->n_pages); + for (i = 0; i < buf->n_pages; ++i) { + if (buf->write) + set_page_dirty_lock(buf->pages[i]); + put_page(buf->pages[i]); + } + kfree(buf->pages); + } else { + if (buf->vma) + vb2_put_vma(buf->vma); + iounmap(buf->vaddr); } - kfree(buf->pages); kfree(buf); } -- 2.20.1