From patchwork Mon Mar 17 19:49:33 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 23125 Received: from mail.tu-berlin.de ([130.149.7.33]) by www.linuxtv.org with esmtp (Exim 4.72) (envelope-from ) id 1WPdXn-00085S-S8; Mon, 17 Mar 2014 20:49:55 +0100 X-tubIT-Incoming-IP: 209.132.180.67 Received: from vger.kernel.org ([209.132.180.67]) by mail.tu-berlin.de (exim-4.72/mailfrontend-5) with esmtp id 1WPdXl-0001v5-7E; Mon, 17 Mar 2014 20:49:55 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751543AbaCQTtt (ORCPT + 1 other); Mon, 17 Mar 2014 15:49:49 -0400 Received: from cantor2.suse.de ([195.135.220.15]:48035 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751350AbaCQTtp (ORCPT ); Mon, 17 Mar 2014 15:49:45 -0400 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 14EDA75021; Mon, 17 Mar 2014 19:49:44 +0000 (UTC) Received: by quack.suse.cz (Postfix, from userid 1000) id 1B9E881ED0; Mon, 17 Mar 2014 20:49:41 +0100 (CET) From: Jan Kara To: linux-mm@kvack.org Cc: linux-media@vger.kernel.org, Jan Kara Subject: [PATCH 6/9] media: vb2: Convert vb2_dc_get_userptr() to use pfns vector Date: Mon, 17 Mar 2014 20:49:33 +0100 Message-Id: <1395085776-8626-7-git-send-email-jack@suse.cz> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1395085776-8626-1-git-send-email-jack@suse.cz> References: <1395085776-8626-1-git-send-email-jack@suse.cz> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-PMX-Version: 6.0.0.2142326, Antispam-Engine: 2.7.2.2107409, Antispam-Data: 2014.3.17.193915 X-PMX-Spam: Gauge=IIIIIIII, Probability=8%, Report=' MULTIPLE_RCPTS 0.1, HTML_00_01 0.05, HTML_00_10 0.05, URI_ENDS_IN_HTML 0, __ANY_URI 0, __CP_URI_IN_BODY 0, __HAS_FROM 0, __HAS_MSGID 0, __HAS_X_MAILER 0, __HAS_X_MAILING_LIST 0, __IN_REP_TO 0, __MIME_TEXT_ONLY 0, __MULTIPLE_RCPTS_CC_X2 0, __SANE_MSGID 0, __SUBJ_ALPHA_END 0, __SXL_RIP_ERROR_SERVFAIL , __SXL_SIG_ERROR_SERVFAIL , __SXL_URI_ERROR_SERVFAIL , __TO_MALFORMED_2 0, __TO_NO_NAME 0, __URI_NO_WWW 0, __URI_NS ' Convert vb2_dc_get_userptr() to use passed vector of pfns. When we are doing that there's no need to allocate page array and some code can be simplified. Signed-off-by: Jan Kara --- drivers/media/v4l2-core/videobuf2-dma-contig.c | 203 ++++--------------------- 1 file changed, 30 insertions(+), 173 deletions(-) diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index c6378d943b89..d445b62a51cf 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -32,15 +32,13 @@ struct vb2_dc_buf { dma_addr_t dma_addr; enum dma_data_direction dma_dir; struct sg_table *dma_sgt; + struct pinned_pfns *pfns; /* MMAP related */ struct vb2_vmarea_handler handler; atomic_t refcount; struct sg_table *sgt_base; - /* USERPTR related */ - struct vm_area_struct *vma; - /* DMABUF related */ struct dma_buf_attachment *db_attach; }; @@ -49,24 +47,6 @@ struct vb2_dc_buf { /* scatterlist table functions */ /*********************************************/ - -static void vb2_dc_sgt_foreach_page(struct sg_table *sgt, - void (*cb)(struct page *pg)) -{ - struct scatterlist *s; - unsigned int i; - - for_each_sg(sgt->sgl, s, sgt->orig_nents, i) { - struct page *page = sg_page(s); - unsigned int n_pages = PAGE_ALIGN(s->offset + s->length) - >> PAGE_SHIFT; - unsigned int j; - - for (j = 0; j < n_pages; ++j, ++page) - cb(page); - } -} - static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) { struct scatterlist *s; @@ -418,101 +398,24 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags) /* callbacks for USERPTR buffers */ /*********************************************/ -static inline int vma_is_io(struct vm_area_struct *vma) -{ - return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); -} - -static int vb2_dc_get_user_pfn(unsigned long start, int n_pages, - struct vm_area_struct *vma, unsigned long *res) -{ - unsigned long pfn, start_pfn, prev_pfn; - unsigned int i; - int ret; - - if (!vma_is_io(vma)) - return -EFAULT; - - ret = follow_pfn(vma, start, &pfn); - if (ret) - return ret; - - start_pfn = pfn; - start += PAGE_SIZE; - - for (i = 1; i < n_pages; ++i, start += PAGE_SIZE) { - prev_pfn = pfn; - ret = follow_pfn(vma, start, &pfn); - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - if (pfn != prev_pfn + 1) - return -EINVAL; - } - - *res = start_pfn; - return 0; -} - -static int vb2_dc_get_user_pages(unsigned long start, struct page **pages, - int n_pages, struct vm_area_struct *vma, int write) -{ - if (vma_is_io(vma)) { - unsigned int i; - - for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) { - unsigned long pfn; - int ret = follow_pfn(vma, start, &pfn); - - if (!pfn_valid(pfn)) - return -EINVAL; - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - pages[i] = pfn_to_page(pfn); - } - } else { - int n; - - n = get_user_pages(current, current->mm, start & PAGE_MASK, - n_pages, write, 1, pages, NULL); - /* negative error means that no page was pinned */ - n = max(n, 0); - if (n != n_pages) { - pr_err("got only %d of %d user pages\n", n, n_pages); - while (n) - put_page(pages[--n]); - return -EFAULT; - } - } - - return 0; -} - -static void vb2_dc_put_dirty_page(struct page *page) -{ - set_page_dirty_lock(page); - put_page(page); -} static void vb2_dc_put_userptr(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt; + int i; + struct page **pages; if (sgt) { dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page); - + pages = pfns_vector_pages(buf->pfns); + for (i = 0; i < pfns_vector_count(buf->pfns); i++) + set_page_dirty_lock(pages[i]); sg_free_table(sgt); kfree(sgt); } - vb2_put_vma(buf->vma); + put_vaddr_pfns(buf->pfns); + pfns_vector_destroy(buf->pfns); kfree(buf); } @@ -553,13 +456,10 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, struct pinned_pfns **ppfn, { struct vb2_dc_conf *conf = alloc_ctx; struct vb2_dc_buf *buf; - unsigned long start; - unsigned long end; + struct pinned_pfns *pfns = *ppfn; unsigned long offset; - struct page **pages; - int n_pages; + int n_pages, i; int ret = 0; - struct vm_area_struct *vma; struct sg_table *sgt; unsigned long contig_size; unsigned long dma_align = dma_get_cache_alignment(); @@ -582,72 +482,38 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, struct pinned_pfns **ppfn, buf->dev = conf->dev; buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE; - start = vaddr & PAGE_MASK; offset = vaddr & ~PAGE_MASK; - end = PAGE_ALIGN(vaddr + size); - n_pages = (end - start) >> PAGE_SHIFT; - - pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL); - if (!pages) { - ret = -ENOMEM; - pr_err("failed to allocate pages table\n"); - goto fail_buf; - } - - /* current->mm->mmap_sem is taken by videobuf2 core */ - vma = find_vma(current->mm, vaddr); - if (!vma) { - pr_err("no vma for address %lu\n", vaddr); - ret = -EFAULT; - goto fail_pages; - } - - if (vma->vm_end < vaddr + size) { - pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size); - ret = -EFAULT; - goto fail_pages; - } + n_pages = pfns_vector_count(pfns); - buf->vma = vb2_get_vma(vma); - if (!buf->vma) { - pr_err("failed to copy vma\n"); - ret = -ENOMEM; - goto fail_pages; - } + ret = pfns_vector_to_pages(pfns); + if (ret < 0) { + unsigned long *nums = pfns_vector_pfns(pfns); - /* extract page list from userspace mapping */ - ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write); - if (ret) { - unsigned long pfn; - if (vb2_dc_get_user_pfn(start, n_pages, vma, &pfn) == 0) { - buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, pfn); - buf->size = size; - kfree(pages); - return buf; - } - - pr_err("failed to get user pages\n"); - goto fail_vma; + /* + * Failed to convert to pages... Check the memory is physically + * contiguous and use direct mapping + */ + for (i = 1; i < n_pages; i++) + if (nums[i-1] + 1 != nums[i]) + goto fail_buf; + buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, nums[0]); + goto out; } sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { pr_err("failed to allocate sg table\n"); ret = -ENOMEM; - goto fail_get_user_pages; + goto fail_buf; } - ret = sg_alloc_table_from_pages(sgt, pages, n_pages, + ret = sg_alloc_table_from_pages(sgt, pfns_vector_pages(pfns), n_pages, offset, size, GFP_KERNEL); if (ret) { pr_err("failed to initialize sg table\n"); goto fail_sgt; } - /* pages are no longer needed */ - kfree(pages); - pages = NULL; - sgt->nents = dma_map_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); if (sgt->nents <= 0) { @@ -665,8 +531,12 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, struct pinned_pfns **ppfn, } buf->dma_addr = sg_dma_address(sgt->sgl); - buf->size = size; buf->dma_sgt = sgt; +out: + buf->size = size; + buf->pfns = pfns; + /* Clear *ppfn so that the caller doesn't free the pfn vector */ + *ppfn = NULL; return buf; @@ -674,24 +544,11 @@ fail_map_sg: dma_unmap_sg(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); fail_sgt_init: - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, put_page); sg_free_table(sgt); fail_sgt: kfree(sgt); -fail_get_user_pages: - if (pages && !vma_is_io(buf->vma)) - while (n_pages) - put_page(pages[--n_pages]); - -fail_vma: - vb2_put_vma(buf->vma); - -fail_pages: - kfree(pages); /* kfree is NULL-proof */ - fail_buf: kfree(buf);