From patchwork Thu Nov 23 06:44:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13465864 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7EAE1C636CB for ; Thu, 23 Nov 2023 07:08:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4E98610E6D2; Thu, 23 Nov 2023 07:08:33 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id F0F4310E6D1 for ; Thu, 23 Nov 2023 07:08:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700723308; x=1732259308; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U5Op4CjhDDAHfKtiDzpe6+9a1b7R8CllBxVTE/TesJE=; b=BzyV5EYpEO4KHfQlgtcryDMJh1uCtJpIKRpkYTzzfadiQWh/WrojtEaF T4mFwzNO/m3qkKvbPlrKBtz0pDe7l1VtlbkgE73D6RirY4N5uvBH0Mkzo jSAlbN2aLeXDylLPQRC4bGCNvDEufYQ0ekg9Sp42wQosnBZM8bC8Lceam JOknIs5S6UoX81+rcuNhvgkMG+h0K++8FNpfXUC40zAYwASxCAw6v2H9u n/erUqw0HXcMjOWz525XIQxFK0C6Ys9Y8wGAltfVg4JQ0PoigyJQZ/I2S ewwv3K3uxrdXtX6h2+IAkTj1dfQqTEPHcATqnxRKU8WOXfmSAK5QDUxah w==; X-IronPort-AV: E=McAfee;i="6600,9927,10902"; a="382612324" X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="382612324" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:24 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="8757714" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:23 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v5 1/5] udmabuf: Use vmf_insert_pfn and VM_PFNMAP for handling mmap Date: Wed, 22 Nov 2023 22:44:39 -0800 Message-Id: <20231123064443.1035709-2-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123064443.1035709-1-vivek.kasireddy@intel.com> References: <20231123064443.1035709-1-vivek.kasireddy@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongwon Kim , David Hildenbrand , Daniel Vetter , Hugh Dickins , Vivek Kasireddy , Peter Xu , Gerd Hoffmann , Jason Gunthorpe , Junxiao Chang , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Add VM_PFNMAP to vm_flags in the mmap handler to ensure that the mappings would be managed without using struct page. And, in the vm_fault handler, use vmf_insert_pfn to share the page's pfn to userspace instead of directly sharing the page (via struct page *). Cc: David Hildenbrand Cc: Daniel Vetter Cc: Mike Kravetz Cc: Hugh Dickins Cc: Peter Xu Cc: Jason Gunthorpe Cc: Gerd Hoffmann Cc: Dongwon Kim Cc: Junxiao Chang Suggested-by: David Hildenbrand Acked-by: David Hildenbrand Signed-off-by: Vivek Kasireddy --- drivers/dma-buf/udmabuf.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index c40645999648..820c993c8659 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -35,12 +35,13 @@ static vm_fault_t udmabuf_vm_fault(struct vm_fault *vmf) struct vm_area_struct *vma = vmf->vma; struct udmabuf *ubuf = vma->vm_private_data; pgoff_t pgoff = vmf->pgoff; + unsigned long pfn; if (pgoff >= ubuf->pagecount) return VM_FAULT_SIGBUS; - vmf->page = ubuf->pages[pgoff]; - get_page(vmf->page); - return 0; + + pfn = page_to_pfn(ubuf->pages[pgoff]); + return vmf_insert_pfn(vma, vmf->address, pfn); } static const struct vm_operations_struct udmabuf_vm_ops = { @@ -56,6 +57,7 @@ static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma) vma->vm_ops = &udmabuf_vm_ops; vma->vm_private_data = ubuf; + vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); return 0; } From patchwork Thu Nov 23 06:44:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13465866 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7FCC2C5AD4C for ; Thu, 23 Nov 2023 07:08:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EE6B010E6D5; Thu, 23 Nov 2023 07:08:33 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 233D710E6D2 for ; Thu, 23 Nov 2023 07:08:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700723309; x=1732259309; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=BBBpGkx9U2ta9/cr9k44Lm2x4HshkBuLRlfX8ndU3Vw=; b=de+DksdnxMt1hhRhaNYrvAt3BsfZuk2Xpr5+HwesUJIIN09MARCFIQ9e DHNoBqUlv5+P1XLnVwmn4ltiw1KlbMG5IhUJlTGhxMILM9kgPTKs0jfTo dDFI4WxWZM63AVZNHXpF9HZwzlyESXfTakG7vqVNDNMaCyWgn8Z2rirGn huXxqFMnnihq08uk8aKpSjR1E8KFdeMOSpGX+Rb61/U8BMAKgHwTUhNxC zGZ/iggG1m+lZrpW9lyMCyGogqIc4IxM76+wjR1Cw6wzR5y11EE/qKHWF J5yeuQLYppMRbViA0SUuzs7udWpHwYkB7q0IkftX/HVjrPtFtstlp6iZ2 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10902"; a="382612332" X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="382612332" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:24 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="8757717" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:23 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v5 2/5] udmabuf: Add back support for mapping hugetlb pages (v4) Date: Wed, 22 Nov 2023 22:44:40 -0800 Message-Id: <20231123064443.1035709-3-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123064443.1035709-1-vivek.kasireddy@intel.com> References: <20231123064443.1035709-1-vivek.kasireddy@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongwon Kim , David Hildenbrand , Daniel Vetter , Hugh Dickins , Vivek Kasireddy , Peter Xu , Gerd Hoffmann , Jason Gunthorpe , Junxiao Chang , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" A user or admin can configure a VMM (Qemu) Guest's memory to be backed by hugetlb pages for various reasons. However, a Guest OS would still allocate (and pin) buffers that are backed by regular 4k sized pages. In order to map these buffers and create dma-bufs for them on the Host, we first need to find the hugetlb pages where the buffer allocations are located and then determine the offsets of individual chunks (within those pages) and use this information to eventually populate a scatterlist. Testcase: default_hugepagesz=2M hugepagesz=2M hugepages=2500 options were passed to the Host kernel and Qemu was launched with these relevant options: qemu-system-x86_64 -m 4096m.... -device virtio-gpu-pci,max_outputs=1,blob=true,xres=1920,yres=1080 -display gtk,gl=on -object memory-backend-memfd,hugetlb=on,id=mem1,size=4096M -machine memory-backend=mem1 Replacing -display gtk,gl=on with -display gtk,gl=off above would exercise the mmap handler. v2: Updated get_sg_table() to manually populate the scatterlist for both huge page and non-huge-page cases. v3: s/offsets/subpgoff/g s/hpoff/mapidx/g v4: Replaced find_get_page_flags() with __filemap_get_folio() to ensure that we only obtain head pages from the mapping Cc: David Hildenbrand Cc: Daniel Vetter Cc: Mike Kravetz Cc: Hugh Dickins Cc: Peter Xu Cc: Jason Gunthorpe Cc: Gerd Hoffmann Cc: Dongwon Kim Cc: Junxiao Chang Acked-by: Mike Kravetz (v2) Signed-off-by: Vivek Kasireddy --- drivers/dma-buf/udmabuf.c | 87 +++++++++++++++++++++++++++++++++------ 1 file changed, 74 insertions(+), 13 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 820c993c8659..d77d119f4048 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -28,6 +29,7 @@ struct udmabuf { struct page **pages; struct sg_table *sg; struct miscdevice *device; + pgoff_t *subpgoff; }; static vm_fault_t udmabuf_vm_fault(struct vm_fault *vmf) @@ -41,6 +43,10 @@ static vm_fault_t udmabuf_vm_fault(struct vm_fault *vmf) return VM_FAULT_SIGBUS; pfn = page_to_pfn(ubuf->pages[pgoff]); + if (ubuf->subpgoff) { + pfn += ubuf->subpgoff[pgoff] >> PAGE_SHIFT; + } + return vmf_insert_pfn(vma, vmf->address, pfn); } @@ -90,23 +96,31 @@ static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf, { struct udmabuf *ubuf = buf->priv; struct sg_table *sg; + struct scatterlist *sgl; + pgoff_t offset; + unsigned long i = 0; int ret; sg = kzalloc(sizeof(*sg), GFP_KERNEL); if (!sg) return ERR_PTR(-ENOMEM); - ret = sg_alloc_table_from_pages(sg, ubuf->pages, ubuf->pagecount, - 0, ubuf->pagecount << PAGE_SHIFT, - GFP_KERNEL); + + ret = sg_alloc_table(sg, ubuf->pagecount, GFP_KERNEL); if (ret < 0) - goto err; + goto err_alloc; + + for_each_sg(sg->sgl, sgl, ubuf->pagecount, i) { + offset = ubuf->subpgoff ? ubuf->subpgoff[i] : 0; + sg_set_page(sgl, ubuf->pages[i], PAGE_SIZE, offset); + } ret = dma_map_sgtable(dev, sg, direction, 0); if (ret < 0) - goto err; + goto err_map; return sg; -err: +err_map: sg_free_table(sg); +err_alloc: kfree(sg); return ERR_PTR(ret); } @@ -143,6 +157,7 @@ static void release_udmabuf(struct dma_buf *buf) for (pg = 0; pg < ubuf->pagecount; pg++) put_page(ubuf->pages[pg]); + kfree(ubuf->subpgoff); kfree(ubuf->pages); kfree(ubuf); } @@ -206,7 +221,10 @@ static long udmabuf_create(struct miscdevice *device, struct udmabuf *ubuf; struct dma_buf *buf; pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit; - struct page *page; + struct page *page, *hpage = NULL; + struct folio *folio; + pgoff_t mapidx, chunkoff, maxchunks; + struct hstate *hpstate; int seals, ret = -EINVAL; u32 i, flags; @@ -242,7 +260,7 @@ static long udmabuf_create(struct miscdevice *device, if (!memfd) goto err; mapping = memfd->f_mapping; - if (!shmem_mapping(mapping)) + if (!shmem_mapping(mapping) && !is_file_hugepages(memfd)) goto err; seals = memfd_fcntl(memfd, F_GET_SEALS, 0); if (seals == -EINVAL) @@ -253,16 +271,58 @@ static long udmabuf_create(struct miscdevice *device, goto err; pgoff = list[i].offset >> PAGE_SHIFT; pgcnt = list[i].size >> PAGE_SHIFT; + if (is_file_hugepages(memfd)) { + if (!ubuf->subpgoff) { + ubuf->subpgoff = kmalloc_array(ubuf->pagecount, + sizeof(*ubuf->subpgoff), + GFP_KERNEL); + if (!ubuf->subpgoff) { + ret = -ENOMEM; + goto err; + } + } + hpstate = hstate_file(memfd); + mapidx = list[i].offset >> huge_page_shift(hpstate); + chunkoff = (list[i].offset & + ~huge_page_mask(hpstate)) >> PAGE_SHIFT; + maxchunks = huge_page_size(hpstate) >> PAGE_SHIFT; + } for (pgidx = 0; pgidx < pgcnt; pgidx++) { - page = shmem_read_mapping_page(mapping, pgoff + pgidx); - if (IS_ERR(page)) { - ret = PTR_ERR(page); - goto err; + if (is_file_hugepages(memfd)) { + if (!hpage) { + folio = __filemap_get_folio(mapping, mapidx, + FGP_ACCESSED, 0); + hpage = IS_ERR(folio) ? NULL: &folio->page; + if (!hpage) { + ret = -EINVAL; + goto err; + } + } + get_page(hpage); + ubuf->pages[pgbuf] = hpage; + ubuf->subpgoff[pgbuf++] = chunkoff << PAGE_SHIFT; + if (++chunkoff == maxchunks) { + put_page(hpage); + hpage = NULL; + chunkoff = 0; + mapidx++; + } + } else { + mapidx = pgoff + pgidx; + page = shmem_read_mapping_page(mapping, mapidx); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + goto err; + } + ubuf->pages[pgbuf++] = page; } - ubuf->pages[pgbuf++] = page; } fput(memfd); memfd = NULL; + if (hpage) { + put_page(hpage); + hpage = NULL; + } } exp_info.ops = &udmabuf_ops; @@ -287,6 +347,7 @@ static long udmabuf_create(struct miscdevice *device, put_page(ubuf->pages[--pgbuf]); if (memfd) fput(memfd); + kfree(ubuf->subpgoff); kfree(ubuf->pages); kfree(ubuf); return ret; From patchwork Thu Nov 23 06:44:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13465865 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA3F1C636BD for ; Thu, 23 Nov 2023 07:08:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C5A7F10E6D4; Thu, 23 Nov 2023 07:08:33 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8481610E6CE for ; Thu, 23 Nov 2023 07:08:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700723308; x=1732259308; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Dk8F7Q/oBhEAmsAwkSHXM8PeNKfeERmLQrUShteflOg=; b=IWz4Gk8jpI+xIL5f05SkMrexOUWhKJI+me0nDBNtxvQnU87YXI0NbUZA a6voikDokwCid8B+mFGBdlYswHE7kGyFR3p5eHqVxWAbEeBFihFnDfKhk jVqnB0nG+pZlXrLeTDdZkLp+K0XhqzPH4TyJkdNCEpmHYezpzbQdiIcpl RFZylAwfUdjONuoWaE4KFDVayz/FR8XIA0yBOe62sFEosyssGjITEVJ2v gRklw1laIWcQ9GGopV9/0h9bSpC+DM7bN5FHhZuIOMY7rBAUuINVbn5EX tw9U0KZdBfKkbVOGgPCFZvs8HESyRUrGs54m5l15q/G5DPnHoskeFSXM6 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10902"; a="382612342" X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="382612342" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:24 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="8757720" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:23 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v5 3/5] mm/gup: Introduce pin_user_pages_fd() for pinning shmem/hugetlbfs file pages (v5) Date: Wed, 22 Nov 2023 22:44:41 -0800 Message-Id: <20231123064443.1035709-4-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123064443.1035709-1-vivek.kasireddy@intel.com> References: <20231123064443.1035709-1-vivek.kasireddy@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongwon Kim , David Hildenbrand , Daniel Vetter , Hugh Dickins , Vivek Kasireddy , Peter Xu , Gerd Hoffmann , Jason Gunthorpe , Junxiao Chang , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" For drivers that would like to longterm-pin the pages associated with a file, the pin_user_pages_fd() API provides an option to not only pin the pages via FOLL_PIN but also to check and migrate them if they reside in movable zone or CMA block. This API currently works with files that belong to either shmem or hugetlbfs. Files belonging to other filesystems are rejected for now. The pages need to be located first before pinning them via FOLL_PIN. If they are found in the page cache, they can be immediately pinned. Otherwise, they need to be allocated using the filesystem specific APIs and then pinned. v2: - Drop gup_flags and improve comments and commit message (David) - Allocate a page if we cannot find in page cache for the hugetlbfs case as well (David) - Don't unpin pages if there is a migration related failure (David) - Drop the unnecessary nr_pages <= 0 check (Jason) - Have the caller of the API pass in file * instead of fd (Jason) v3: (David) - Enclose the huge page allocation code with #ifdef CONFIG_HUGETLB_PAGE (Build error reported by kernel test robot ) - Don't forget memalloc_pin_restore() on non-migration related errors - Improve the readability of the cleanup code associated with non-migration related errors - Augment the comments by describing FOLL_LONGTERM like behavior - Include the R-b tag from Jason v4: - Remove the local variable "page" and instead use 3 return statements in alloc_file_page() (David) - Add the R-b tag from David v5: (David) - For hugetlb case, ensure that we only obtain head pages from the mapping by using __filemap_get_folio() instead of find_get_page_flags() - Handle -EEXIST when two or more potential users try to simultaneously add a huge page to the mapping by forcing them to retry on failure Cc: David Hildenbrand Cc: Daniel Vetter Cc: Mike Kravetz Cc: Hugh Dickins Cc: Peter Xu Cc: Gerd Hoffmann Cc: Dongwon Kim Cc: Junxiao Chang Suggested-by: Jason Gunthorpe Reviewed-by: Jason Gunthorpe (v2) Reviewed-by: David Hildenbrand (v3) Signed-off-by: Vivek Kasireddy --- include/linux/mm.h | 2 + mm/gup.c | 114 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 116 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 418d26608ece..1b675fa35059 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2472,6 +2472,8 @@ long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); +long pin_user_pages_fd(struct file *file, pgoff_t start, + unsigned long nr_pages, struct page **pages); int get_user_pages_fast(unsigned long start, int nr_pages, unsigned int gup_flags, struct page **pages); diff --git a/mm/gup.c b/mm/gup.c index 231711efa390..ab1056b3e75b 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -3410,3 +3410,117 @@ long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, &locked, gup_flags); } EXPORT_SYMBOL(pin_user_pages_unlocked); + +static struct page *alloc_file_page(struct file *file, pgoff_t idx) +{ +#ifdef CONFIG_HUGETLB_PAGE + struct folio *folio; + int err; + + if (is_file_hugepages(file)) { + folio = alloc_hugetlb_folio_nodemask(hstate_file(file), + NUMA_NO_NODE, + NULL, + GFP_USER); + if (folio && folio_try_get(folio)) { + err = hugetlb_add_to_page_cache(folio, + file->f_mapping, + idx); + if (err) { + folio_put(folio); + free_huge_folio(folio); + return ERR_PTR(err); + } + return &folio->page; + } + return ERR_PTR(-ENOMEM); + } +#endif + return shmem_read_mapping_page(file->f_mapping, idx); +} + +/** + * pin_user_pages_fd() - pin user pages associated with a file + * @file: the file whose pages are to be pinned + * @start: starting file offset + * @nr_pages: number of pages from start to pin + * @pages: array that receives pointers to the pages pinned. + * Should be at-least nr_pages long. + * + * Attempt to pin pages associated with a file that belongs to either shmem + * or hugetlb. The pages are either found in the page cache or allocated if + * necessary. Once the pages are located, they are all pinned via FOLL_PIN. + * And, these pinned pages need to be released either using unpin_user_pages() + * or unpin_user_page(). + * + * It must be noted that the pages may be pinned for an indefinite amount + * of time. And, in most cases, the duration of time they may stay pinned + * would be controlled by the userspace. This behavior is effectively the + * same as using FOLL_LONGTERM with other GUP APIs. + * + * Returns number of pages pinned. This would be equal to the number of + * pages requested. If no pages were pinned, it returns -errno. + */ +long pin_user_pages_fd(struct file *file, pgoff_t start, + unsigned long nr_pages, struct page **pages) +{ + struct page *page; + struct folio *folio; + unsigned int flags, i; + long ret; + + if (start < 0) + return -EINVAL; + + if (!file) + return -EINVAL; + + if (!shmem_file(file) && !is_file_hugepages(file)) + return -EINVAL; + + flags = memalloc_pin_save(); + do { + for (i = 0; i < nr_pages; i++) { + /* + * In most cases, we should be able to find the page + * in the page cache. If we cannot find it, we try to + * allocate one and add it to the page cache. + */ +retry: + folio = __filemap_get_folio(file->f_mapping, + start + i, + FGP_ACCESSED, 0); + + page = IS_ERR(folio) ? NULL: &folio->page; + if (!page) { + page = alloc_file_page(file, start + i); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + if (ret == -EEXIST) + goto retry; + goto err; + } + } + ret = try_grab_page(page, FOLL_PIN); + if (unlikely(ret)) + goto err; + + pages[i] = page; + put_page(pages[i]); + } + + ret = check_and_migrate_movable_pages(nr_pages, pages); + } while (ret == -EAGAIN); + + memalloc_pin_restore(flags); + return ret ? ret : nr_pages; +err: + memalloc_pin_restore(flags); + while (i-- > 0) + if (pages[i]) + unpin_user_page(pages[i]); + + return ret; +} +EXPORT_SYMBOL_GPL(pin_user_pages_fd); + From patchwork Thu Nov 23 06:44:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13465867 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 65584C61D97 for ; Thu, 23 Nov 2023 07:08:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CE40C10E6D6; Thu, 23 Nov 2023 07:08:34 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4DAEE10E6D3 for ; Thu, 23 Nov 2023 07:08:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700723309; x=1732259309; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=JveC5J73AXuIFwcZCQaP9Gn0jICa/20AkT8Zw92eLmk=; b=iMP4b4CJpA02vl90yrAQbo7TONq2fZKBFC5TewDFfkm1LKTC8hkKl6Us jCNGEMJRsv8S75VIfQxoTVP0kBo0VLzFhrlQXoPgU2THYv5f/sPViJF7K QoUkHcO1nquF1Nf4iU/4wzrYVmovBtYmjpX69y1F6VyDtxVXZDsRFSydK lplQcrTul8zNeMWatUDj+P1PXKJub4WHbQITPld2JIMBOWZhg9SPf+nfI KTEkMMmXV8cogRtyRsC5VuAzsuTgDvvrkLgoBnVZlsRdQABcFKPrUeptR QNOXFAcvn9jLTJa39P6PrYuECKuW/ZJ/kA+VolCXvA5fLYzWjCLH95u3W w==; X-IronPort-AV: E=McAfee;i="6600,9927,10902"; a="382612351" X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="382612351" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="8757723" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:24 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v5 4/5] udmabuf: Pin the pages using pin_user_pages_fd() API (v3) Date: Wed, 22 Nov 2023 22:44:42 -0800 Message-Id: <20231123064443.1035709-5-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123064443.1035709-1-vivek.kasireddy@intel.com> References: <20231123064443.1035709-1-vivek.kasireddy@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongwon Kim , David Hildenbrand , Daniel Vetter , Hugh Dickins , Vivek Kasireddy , Peter Xu , Gerd Hoffmann , Jason Gunthorpe , Junxiao Chang , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Using pin_user_pages_fd() will ensure that the pages are pinned correctly using FOLL_PIN. And, this also ensures that we don't accidentally break features such as memory hotunplug as it would not allow pinning pages in the movable zone. Using this new API also simplifies the code as we no longer have to deal with extracting individual pages from their mappings. As a result, we can drop some of the local variables such as page, hpage, mapping, etc. v2: - Adjust to the change in signature of pin_user_pages_fd() by passing in file * instead of fd. v3: - Limit the changes in this patch only to those that are required for using pin_user_pages_fd() - Slightly improve the commit message Cc: David Hildenbrand Cc: Daniel Vetter Cc: Mike Kravetz Cc: Hugh Dickins Cc: Peter Xu Cc: Jason Gunthorpe Cc: Gerd Hoffmann Cc: Dongwon Kim Cc: Junxiao Chang Signed-off-by: Vivek Kasireddy --- drivers/dma-buf/udmabuf.c | 61 ++++++++++++++------------------------- 1 file changed, 22 insertions(+), 39 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index d77d119f4048..883bd97e4076 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -156,7 +156,8 @@ static void release_udmabuf(struct dma_buf *buf) put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL); for (pg = 0; pg < ubuf->pagecount; pg++) - put_page(ubuf->pages[pg]); + unpin_user_page(ubuf->pages[pg]); + kfree(ubuf->subpgoff); kfree(ubuf->pages); kfree(ubuf); @@ -217,15 +218,13 @@ static long udmabuf_create(struct miscdevice *device, { DEFINE_DMA_BUF_EXPORT_INFO(exp_info); struct file *memfd = NULL; - struct address_space *mapping = NULL; struct udmabuf *ubuf; struct dma_buf *buf; - pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit; - struct page *page, *hpage = NULL; - struct folio *folio; + pgoff_t pgcnt, pgbuf = 0, pglimit, nr_pages; pgoff_t mapidx, chunkoff, maxchunks; struct hstate *hpstate; - int seals, ret = -EINVAL; + long ret = -EINVAL; + int seals; u32 i, flags; ubuf = kzalloc(sizeof(*ubuf), GFP_KERNEL); @@ -259,8 +258,7 @@ static long udmabuf_create(struct miscdevice *device, memfd = fget(list[i].memfd); if (!memfd) goto err; - mapping = memfd->f_mapping; - if (!shmem_mapping(mapping) && !is_file_hugepages(memfd)) + if (!shmem_file(memfd) && !is_file_hugepages(memfd)) goto err; seals = memfd_fcntl(memfd, F_GET_SEALS, 0); if (seals == -EINVAL) @@ -269,7 +267,7 @@ static long udmabuf_create(struct miscdevice *device, if ((seals & SEALS_WANTED) != SEALS_WANTED || (seals & SEALS_DENIED) != 0) goto err; - pgoff = list[i].offset >> PAGE_SHIFT; + mapidx = list[i].offset >> PAGE_SHIFT; pgcnt = list[i].size >> PAGE_SHIFT; if (is_file_hugepages(memfd)) { if (!ubuf->subpgoff) { @@ -287,42 +285,26 @@ static long udmabuf_create(struct miscdevice *device, ~huge_page_mask(hpstate)) >> PAGE_SHIFT; maxchunks = huge_page_size(hpstate) >> PAGE_SHIFT; } - for (pgidx = 0; pgidx < pgcnt; pgidx++) { + + do { + nr_pages = shmem_file(memfd) ? pgcnt : 1; + ret = pin_user_pages_fd(memfd, mapidx, nr_pages, + ubuf->pages + pgbuf); + if (ret < 0) + goto err; + if (is_file_hugepages(memfd)) { - if (!hpage) { - folio = __filemap_get_folio(mapping, mapidx, - FGP_ACCESSED, 0); - hpage = IS_ERR(folio) ? NULL: &folio->page; - if (!hpage) { - ret = -EINVAL; - goto err; - } - } - get_page(hpage); - ubuf->pages[pgbuf] = hpage; - ubuf->subpgoff[pgbuf++] = chunkoff << PAGE_SHIFT; + ubuf->subpgoff[pgbuf] = chunkoff << PAGE_SHIFT; if (++chunkoff == maxchunks) { - put_page(hpage); - hpage = NULL; chunkoff = 0; mapidx++; } - } else { - mapidx = pgoff + pgidx; - page = shmem_read_mapping_page(mapping, mapidx); - if (IS_ERR(page)) { - ret = PTR_ERR(page); - goto err; - } - ubuf->pages[pgbuf++] = page; } - } + pgbuf += nr_pages; + pgcnt -= nr_pages; + } while (pgcnt > 0); fput(memfd); memfd = NULL; - if (hpage) { - put_page(hpage); - hpage = NULL; - } } exp_info.ops = &udmabuf_ops; @@ -343,8 +325,9 @@ static long udmabuf_create(struct miscdevice *device, return dma_buf_fd(buf, flags); err: - while (pgbuf > 0) - put_page(ubuf->pages[--pgbuf]); + while (pgbuf-- > 0) + if (ubuf->pages[pgbuf]) + unpin_user_page(ubuf->pages[pgbuf]); if (memfd) fput(memfd); kfree(ubuf->subpgoff); From patchwork Thu Nov 23 06:44:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13465863 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6574CC5AD4C for ; Thu, 23 Nov 2023 07:08:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1CBF310E6D1; Thu, 23 Nov 2023 07:08:33 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id CD9E410E6D1 for ; Thu, 23 Nov 2023 07:08:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700723309; x=1732259309; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=r39C9fURv/tYjjTgfRvVfOiacLkGBXJF65fG2x4l+b0=; b=R/Hjev8U9wJd5oaQyh293mvSadtUfnh9E1KvRxisOjxLCrt1OCjjbvBF NOJ4kPf5ZuEFsvj2b5PcOWOXJoHK6qxAJYY/iA/1CbjfYjFrRILnfAuX9 VT2nGT/OzDP/fEnUdyl29XrxbwITK7+nMUBbBQUQjUC1uN1W/+sMxZNey 4EN0/Tq8iZvTVT1W1ypfsMeiQK/lkc4VUkCykw6StGLVZujJRpfzGCRgt G5Cpc7gIR/YPYlQi4idAKSQpAagFmlmOQUkXwRLbY3FtVbjauRIoL3oqm 8HmbARMJUXxRPOP7unS/5/zXHlovToMx5aUbYFII0RIdJC7Jzbk6riqjQ Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10902"; a="382612350" X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="382612350" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,220,1695711600"; d="scan'208";a="8757726" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Nov 2023 23:08:24 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v5 5/5] selftests/dma-buf/udmabuf: Add tests to verify data after page migration Date: Wed, 22 Nov 2023 22:44:43 -0800 Message-Id: <20231123064443.1035709-6-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123064443.1035709-1-vivek.kasireddy@intel.com> References: <20231123064443.1035709-1-vivek.kasireddy@intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongwon Kim , David Hildenbrand , Daniel Vetter , Hugh Dickins , Vivek Kasireddy , Peter Xu , Gerd Hoffmann , Jason Gunthorpe , Junxiao Chang , Shuah Khan , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Since the memfd pages associated with a udmabuf may be migrated as part of udmabuf create, we need to verify the data coherency after successful migration. The new tests added in this patch try to do just that using 4k sized pages and also 2 MB sized huge pages for the memfd. Successful completion of the tests would mean that there is no disconnect between the memfd pages and the ones associated with a udmabuf. And, these tests can also be augmented in the future to test newer udmabuf features (such as handling memfd hole punch). Cc: Shuah Khan Cc: David Hildenbrand Cc: Daniel Vetter Cc: Mike Kravetz Cc: Hugh Dickins Cc: Peter Xu Cc: Jason Gunthorpe Cc: Gerd Hoffmann Cc: Dongwon Kim Cc: Junxiao Chang Based-on-patch-by: Mike Kravetz Signed-off-by: Vivek Kasireddy --- .../selftests/drivers/dma-buf/udmabuf.c | 151 +++++++++++++++++- 1 file changed, 147 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/drivers/dma-buf/udmabuf.c b/tools/testing/selftests/drivers/dma-buf/udmabuf.c index c812080e304e..d76c813fe652 100644 --- a/tools/testing/selftests/drivers/dma-buf/udmabuf.c +++ b/tools/testing/selftests/drivers/dma-buf/udmabuf.c @@ -9,26 +9,132 @@ #include #include #include +#include #include #include +#include #include #include #define TEST_PREFIX "drivers/dma-buf/udmabuf" #define NUM_PAGES 4 +#define NUM_ENTRIES 4 +#define MEMFD_SIZE 1024 /* in pages */ -static int memfd_create(const char *name, unsigned int flags) +static unsigned int page_size; + +static int create_memfd_with_seals(off64_t size, bool hpage) +{ + int memfd, ret; + unsigned int flags = MFD_ALLOW_SEALING; + + if (hpage) + flags |= MFD_HUGETLB; + + memfd = memfd_create("udmabuf-test", flags); + if (memfd < 0) { + printf("%s: [skip,no-memfd]\n", TEST_PREFIX); + exit(77); + } + + ret = fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK); + if (ret < 0) { + printf("%s: [skip,fcntl-add-seals]\n", TEST_PREFIX); + exit(77); + } + + ret = ftruncate(memfd, size); + if (ret == -1) { + printf("%s: [FAIL,memfd-truncate]\n", TEST_PREFIX); + exit(1); + } + + return memfd; +} + +static int create_udmabuf_list(int devfd, int memfd, off64_t memfd_size) +{ + struct udmabuf_create_list *list; + int ubuf_fd, i; + + list = malloc(sizeof(struct udmabuf_create_list) + + sizeof(struct udmabuf_create_item) * NUM_ENTRIES); + if (!list) { + printf("%s: [FAIL, udmabuf-malloc]\n", TEST_PREFIX); + exit(1); + } + + for (i = 0; i < NUM_ENTRIES; i++) { + list->list[i].memfd = memfd; + list->list[i].offset = i * (memfd_size / NUM_ENTRIES); + list->list[i].size = getpagesize() * NUM_PAGES; + } + + list->count = NUM_ENTRIES; + list->flags = UDMABUF_FLAGS_CLOEXEC; + ubuf_fd = ioctl(devfd, UDMABUF_CREATE_LIST, list); + free(list); + if (ubuf_fd < 0) { + printf("%s: [FAIL, udmabuf-create]\n", TEST_PREFIX); + exit(1); + } + + return ubuf_fd; +} + +static void write_to_memfd(void *addr, off64_t size, char chr) +{ + int i; + + for (i = 0; i < size / page_size; i++) { + *((char *)addr + (i * page_size)) = chr; + } +} + +static void *mmap_fd(int fd, off64_t size) { - return syscall(__NR_memfd_create, name, flags); + void *addr; + + addr = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); + if (addr == MAP_FAILED) { + printf("%s: ubuf_fd mmap fail\n", TEST_PREFIX); + exit(1); + } + + return addr; +} + +static int compare_chunks(void *addr1, void *addr2, off64_t memfd_size) +{ + off64_t off; + int i = 0, j, k = 0, ret = 0; + char char1, char2; + + while (i < NUM_ENTRIES) { + off = i * (memfd_size / NUM_ENTRIES); + for (j = 0; j < NUM_PAGES; j++, k++) { + char1 = *((char *)addr1 + off + (j * getpagesize())); + char2 = *((char *)addr2 + (k * getpagesize())); + if (char1 != char2) { + ret = -1; + goto err; + } + } + i++; + } +err: + munmap(addr1, memfd_size); + munmap(addr2, NUM_ENTRIES * NUM_PAGES * getpagesize()); + return ret; } int main(int argc, char *argv[]) { struct udmabuf_create create; int devfd, memfd, buf, ret; - off_t size; - void *mem; + off64_t size; + void *addr1, *addr2; devfd = open("/dev/udmabuf", O_RDWR); if (devfd < 0) { @@ -90,6 +196,9 @@ int main(int argc, char *argv[]) } /* should work */ + page_size = getpagesize(); + addr1 = mmap_fd(memfd, size); + write_to_memfd(addr1, size, 'a'); create.memfd = memfd; create.offset = 0; create.size = size; @@ -98,6 +207,40 @@ int main(int argc, char *argv[]) printf("%s: [FAIL,test-4]\n", TEST_PREFIX); exit(1); } + munmap(addr1, size); + close(buf); + close(memfd); + + /* should work (migration of 4k size pages)*/ + size = MEMFD_SIZE * page_size; + memfd = create_memfd_with_seals(size, false); + addr1 = mmap_fd(memfd, size); + write_to_memfd(addr1, size, 'a'); + buf = create_udmabuf_list(devfd, memfd, size); + addr2 = mmap_fd(buf, NUM_PAGES * NUM_ENTRIES * getpagesize()); + write_to_memfd(addr1, size, 'b'); + ret = compare_chunks(addr1, addr2, size); + if (ret < 0) { + printf("%s: [FAIL,test-5]\n", TEST_PREFIX); + exit(1); + } + close(buf); + close(memfd); + + /* should work (migration of 2MB size huge pages)*/ + page_size = getpagesize() * 512; /* 2 MB */ + size = MEMFD_SIZE * page_size; + memfd = create_memfd_with_seals(size, true); + addr1 = mmap_fd(memfd, size); + write_to_memfd(addr1, size, 'a'); + buf = create_udmabuf_list(devfd, memfd, size); + addr2 = mmap_fd(buf, NUM_PAGES * NUM_ENTRIES * getpagesize()); + write_to_memfd(addr1, size, 'b'); + ret = compare_chunks(addr1, addr2, size); + if (ret < 0) { + printf("%s: [FAIL,test-6]\n", TEST_PREFIX); + exit(1); + } fprintf(stderr, "%s: ok\n", TEST_PREFIX); close(buf);