From patchwork Mon Nov 6 06:15:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13446267 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 27965C4332F for ; Mon, 6 Nov 2023 06:17:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D000B10E26F; Mon, 6 Nov 2023 06:17:39 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8803D10E26A for ; Mon, 6 Nov 2023 06:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699251456; x=1730787456; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LRgtqEGhnRjdv65luGGLdEpI5+g8BPuw2uD/fg3QljU=; b=fQnCSK9xjZSTPc6TYPqK0oReIpFHLJIPyvj7cekPST8TygpeHVlW3nOW m6o2Ar2j1KjsNLxKfb1ftCKaYaEQfD1yJQweKPNcWxUMLKoLuokgeVYWo tk796pdtbOtb4xrSHJ8IMbdBC2dNMFaeRaRa6BHObT0ZHWwUfYLBZfiCx /MCAxvR1jZMvwhpLUq6P/XD4j1JrDUULaES93WGn/xf+PFMc//uqzm9D7 BhCXwFhqS4tfua1Ly4/042dlHBB1bff+B8GG9rPtphIjC530So91uf5EN klB84tlwwAh/UFnN+shrY21U8cBXGOVoOr+1/txF8k5+PSmZfpnPjIXyQ Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="393113916" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="393113916" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:35 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="797213047" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="797213047" Received: from vkasired-desk2.fm.intel.com ([10.105.128.7]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:35 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v2 1/3] mm/gup: Introduce pin_user_pages_fd() for pinning shmem/hugetlbfs file pages (v2) Date: Sun, 5 Nov 2023 22:15:39 -0800 Message-Id: <20231106061541.507116-2-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231106061541.507116-1-vivek.kasireddy@intel.com> References: <20231106061541.507116-1-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) 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 Signed-off-by: Vivek Kasireddy Reviewed-by: Jason Gunthorpe --- include/linux/mm.h | 2 + mm/gup.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 101 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index bf5d0b1b16f4..f6cc17b14653 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2457,6 +2457,8 @@ 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 2f8a2d89fde1..d30b9dfebbb6 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -3400,3 +3400,102 @@ 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) +{ + struct page *page = ERR_PTR(-ENOMEM); + struct folio *folio; + int err; + + if (shmem_file(file)) + return shmem_read_mapping_page(file->f_mapping, idx); + + folio = alloc_hugetlb_folio_nodemask(hstate_file(file), + NUMA_NO_NODE, + NULL, + GFP_USER); + if (folio && folio_try_get(folio)) { + page = &folio->page; + err = hugetlb_add_to_page_cache(folio, file->f_mapping, idx); + if (err) { + folio_put(folio); + free_huge_folio(folio); + page = ERR_PTR(err); + } + } + + return page; +} + +/** + * 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 hugetlbfs. 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 using unpin_user_pages() or + * unpin_user_page(). + * + * 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; + 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. + */ + page = find_get_page_flags(file->f_mapping, + start + i, + FGP_ACCESSED); + if (!page) { + page = alloc_file_page(file, start + i); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + 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: + while (i > 0 && pages[--i]) + unpin_user_page(pages[i]); + + return ret; +} +EXPORT_SYMBOL_GPL(pin_user_pages_fd); + From patchwork Mon Nov 6 06:15:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13446268 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 39508C4167D for ; Mon, 6 Nov 2023 06:17:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EC98310E271; Mon, 6 Nov 2023 06:17:39 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id BE58910E107 for ; Mon, 6 Nov 2023 06:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699251456; x=1730787456; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=nVN0HkxWtfg8eXqDo7dzNjDMWcgdPswKsobFnSzYfJc=; b=P/euXDAxMJQpewsCu5wwmYfKrD7xm+UtATgKcwY4HEKNfyQLUrLTKMt6 lsYpIpNRVO+9WMBpPzeI4CHQpAobVjOkmzf+1ykDsO6n33oXTDw3q76uF uckAt7tmABDy/WD+8gDH803RP/5ayzTFMosNa6uSXH2m0eH0ZlmwBpVx9 6dBwtqzv0V4usvHO7oUOV4+MRH3nsnPswcnABLs4DSKVM5aYJdpb4MvQB zzLzaBH+PtXU1Lf58UXi5SiFl7hfhcstAhLZGyZj06/K4PWSD1NFaDNCP WzGFS/+QhGm70KUw+7aaZKrOeq16JULrQas2CApRxotj4BiSaKfUSrDHz A==; X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="393113924" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="393113924" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:35 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="797213050" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="797213050" Received: from vkasired-desk2.fm.intel.com ([10.105.128.7]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:35 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v2 2/3] udmabuf: Pin the pages using pin_user_pages_fd() API (v2) Date: Sun, 5 Nov 2023 22:15:40 -0800 Message-Id: <20231106061541.507116-3-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231106061541.507116-1-vivek.kasireddy@intel.com> References: <20231106061541.507116-1-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. This patch also adds back support for mapping hugetlbfs pages by noting the subpage offsets within the huge pages and uses this information while populating the scatterlist. v2: - Adjust to the change in signature of pin_user_pages_fd() by passing in file * instead of fd. 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 | 81 +++++++++++++++++++++++++++++---------- 1 file changed, 60 insertions(+), 21 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 820c993c8659..aa47af2b547f 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) @@ -90,23 +92,31 @@ 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); } @@ -142,7 +152,9 @@ 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); } @@ -202,12 +214,13 @@ 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; - int seals, ret = -EINVAL; + pgoff_t pgoff, pgcnt, pgbuf = 0, pglimit, nr_pages; + pgoff_t subpgoff, maxsubpgs; + struct hstate *hpstate; + long ret = -EINVAL; + int seals; u32 i, flags; ubuf = kzalloc(sizeof(*ubuf), GFP_KERNEL); @@ -241,8 +254,7 @@ static long udmabuf_create(struct miscdevice *device, memfd = fget(list[i].memfd); if (!memfd) goto err; - mapping = memfd->f_mapping; - if (!shmem_mapping(mapping)) + if (!shmem_file(memfd) && !is_file_hugepages(memfd)) goto err; seals = memfd_fcntl(memfd, F_GET_SEALS, 0); if (seals == -EINVAL) @@ -253,14 +265,40 @@ static long udmabuf_create(struct miscdevice *device, goto err; pgoff = list[i].offset >> PAGE_SHIFT; pgcnt = list[i].size >> PAGE_SHIFT; - for (pgidx = 0; pgidx < pgcnt; pgidx++) { - page = shmem_read_mapping_page(mapping, pgoff + pgidx); - if (IS_ERR(page)) { - ret = PTR_ERR(page); + 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); + pgoff = list[i].offset >> huge_page_shift(hpstate); + subpgoff = (list[i].offset & + ~huge_page_mask(hpstate)) >> PAGE_SHIFT; + maxsubpgs = huge_page_size(hpstate) >> PAGE_SHIFT; + } + + do { + nr_pages = shmem_file(memfd) ? pgcnt : 1; + ret = pin_user_pages_fd(memfd, pgoff, nr_pages, + ubuf->pages + pgbuf); + if (ret < 0) goto err; + + if (is_file_hugepages(memfd)) { + ubuf->subpgoff[pgbuf] = subpgoff << PAGE_SHIFT; + if (++subpgoff == maxsubpgs) { + subpgoff = 0; + pgoff++; + } } - ubuf->pages[pgbuf++] = page; - } + pgbuf += nr_pages; + pgcnt -= nr_pages; + } while (pgcnt > 0); fput(memfd); memfd = NULL; } @@ -283,10 +321,11 @@ 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 && ubuf->pages[--pgbuf]) + unpin_user_page(ubuf->pages[pgbuf]); if (memfd) fput(memfd); + kfree(ubuf->subpgoff); kfree(ubuf->pages); kfree(ubuf); return ret; From patchwork Mon Nov 6 06:15:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 13446265 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 249FBC4332F for ; Mon, 6 Nov 2023 06:17:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8276710E107; Mon, 6 Nov 2023 06:17:38 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id E95CC10E26C for ; Mon, 6 Nov 2023 06:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1699251456; x=1730787456; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=r39C9fURv/tYjjTgfRvVfOiacLkGBXJF65fG2x4l+b0=; b=cw0Dvf5zC5zFATgrCqlq+6JE7TCNGzC9SgQL2be5pDoVhxhUY8hm4bwg njsjCUobghNWJBuEizVssK6RBkdgA3J6Xa98ZV+AcuX1DYqEveSPU4NE2 7QcYHilTfWOnNyYRPvI04jNgCgo8jcnm0/dhTt5iBab7FvIVKRvDG/5M/ BPaongqoyb+TaopQE1v2m6MhwpBbOzNcqOBWyZhbKRcW8GayG7727R4YC Kh9/vxQyZ242dWw7ZA0b47TYHpiMdnu3NrSPNSieuj4rHwOwIw9MHI2Rl moEVwmUOHpO9or01CZ/6wbgEmebDALMaPvfrQT6NBinsUKFc5n1bbY3aq g==; X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="393113932" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="393113932" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:36 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10885"; a="797213053" X-IronPort-AV: E=Sophos;i="6.03,280,1694761200"; d="scan'208";a="797213053" Received: from vkasired-desk2.fm.intel.com ([10.105.128.7]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2023 22:17:35 -0800 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, linux-mm@kvack.org Subject: [PATCH v2 3/3] selftests/dma-buf/udmabuf: Add tests to verify data after page migration Date: Sun, 5 Nov 2023 22:15:41 -0800 Message-Id: <20231106061541.507116-4-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231106061541.507116-1-vivek.kasireddy@intel.com> References: <20231106061541.507116-1-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);