From mboxrd@z Thu Jan 1 00:00:00 1970 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 D893AC2BA18 for ; Wed, 12 Jun 2024 02:15:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CE67810E76D; Wed, 12 Jun 2024 02:15:43 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="ix+YOCUg"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0518210E763 for ; Wed, 12 Jun 2024 02:15:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1718158538; x=1749694538; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=+2hP1ozoSKU7oMWnz2whLJ9mktL+AIUd7zW03UlZhWw=; b=ix+YOCUgAICkO1FB6vb+6OYgV4novPe2cCxf7tCnrtrTd2e/o+f6S1+8 14liF3HQxar7bse/fOK7DPToe7L2of0Zq3jBZWbPMHGR8SSmNzhn3Zv1b P3ltAX3cwjswJElj1TsuEY+SmuEx0yuEuibw2BsHEGrW2RyfJMFldHdA9 vpvHVsufV3CJ1FLUDk7+gM3Db7eocRk2F1kJBp3432n0K0c92XPLU3tJj XvBfK23/M4PqgM0D3Ja+x0gZH7VAH7CySf2P1w9CcCcuDXum3Gjjd/s6m 1Zm0abTdPlyvKciuCPcSWKyQ7HEC/Z0//rmcVoCT+GQewvMhwytWHN5Nl Q==; X-CSE-ConnectionGUID: 9JDj1llnSy2IH9cv4nbmEA== X-CSE-MsgGUID: 0sEJHYgQS+WzVoe06CLD1w== X-IronPort-AV: E=McAfee;i="6600,9927,11100"; a="37427795" X-IronPort-AV: E=Sophos;i="6.08,231,1712646000"; d="scan'208";a="37427795" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jun 2024 19:15:27 -0700 X-CSE-ConnectionGUID: l15bVFoFQ5yygdgcUKAlAg== X-CSE-MsgGUID: P4xl1jZfRDeYz8GsdNu0ZQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,231,1712646000"; d="scan'208";a="44763628" Received: from szeng-desk.jf.intel.com ([10.165.21.149]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jun 2024 19:15:27 -0700 From: Oak Zeng To: intel-xe@lists.freedesktop.org Subject: [CI 12/43] drm/svm: Introduce helper to remap drm memory region Date: Tue, 11 Jun 2024 22:25:34 -0400 Message-Id: <20240612022605.385062-12-oak.zeng@intel.com> X-Mailer: git-send-email 2.26.3 In-Reply-To: <20240612022605.385062-1-oak.zeng@intel.com> References: <20240612022605.385062-1-oak.zeng@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" Helper function drm_svm_register_mem_region to remap GPU vram using devm_memremap_pages, so each GPU vram page is backed by struct page. Those struct pages are created to allow hmm migrate buffer b/t GPU vram and CPU system memory using existing Linux migration mechanism (i.e., migrating b/t CPU system memory and hard disk). This is prepare work to enable svm (shared virtual memory) through Linux kernel hmm framework. The memory remap's page map type is set to MEMORY_DEVICE_PRIVATE for now. This means even though each GPU vram page get a struct page and can be mapped in CPU page table, but such pages are treated as GPU's private resource, so CPU can't access them. If CPU access such page, a page fault is triggered and page will be migrate to system memory. For GPU device which supports coherent memory protocol b/t CPU and GPU (such as CXL and CAPI protocol), we can remap device memory as MEMORY_DEVICE_COHERENT. This is TBD. Cc: Daniel Vetter Cc: Dave Airlie Cc: Thomas Hellström Cc: Matthew Brost Cc: Christian König Cc: Felix Kuehling Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Brian Welty Cc: Himal Prasad Ghimiray Cc: Signed-off-by: Oak Zeng Co-developed-by: Niranjana Vishwanathapura Signed-off-by: Niranjana Vishwanathapura --- drivers/gpu/drm/drm_svm.c | 50 +++++++++++++++++++++++++++++++++++++++ include/drm/drm_svm.h | 2 ++ 2 files changed, 52 insertions(+) diff --git a/drivers/gpu/drm/drm_svm.c b/drivers/gpu/drm/drm_svm.c index 95c907ae3144..4b1c45466130 100644 --- a/drivers/gpu/drm/drm_svm.c +++ b/drivers/gpu/drm/drm_svm.c @@ -13,6 +13,7 @@ #include #include #include +#include #include static u64 __npages_in_range(unsigned long start, unsigned long end) @@ -304,3 +305,52 @@ int drm_svm_hmmptr_populate(struct drm_hmmptr *hmmptr, void *owner, u64 start, u return ret; } EXPORT_SYMBOL_GPL(drm_svm_hmmptr_populate); + +static struct dev_pagemap_ops drm_devm_pagemap_ops; + +/** + * drm_svm_register_mem_region: Remap and provide memmap backing for device memory + * @drm: drm device who want to register a memory region + * @mr: memory region to register + * + * This remap device memory to host physical address space and create + * struct page to back device memory + * + * Return: 0 on success standard error code otherwise + */ +int drm_svm_register_mem_region(const struct drm_device *drm, struct drm_mem_region *mr) +{ + struct device *dev = &to_pci_dev(drm->dev)->dev; + struct resource *res; + void *addr; + int ret; + + res = devm_request_free_mem_region(dev, &iomem_resource, + mr->usable_size); + if (IS_ERR(res)) { + ret = PTR_ERR(res); + return ret; + } + + drm_devm_pagemap_ops.page_free = mr->mr_ops.drm_mem_region_free_page; + mr->pagemap.type = MEMORY_DEVICE_PRIVATE; + mr->pagemap.range.start = res->start; + mr->pagemap.range.end = res->end; + mr->pagemap.nr_range = 1; + mr->pagemap.ops = &drm_devm_pagemap_ops; + mr->pagemap.owner = mr->mr_ops.drm_mem_region_pagemap_owner(mr); + addr = devm_memremap_pages(dev, &mr->pagemap); + if (IS_ERR(addr)) { + devm_release_mem_region(dev, res->start, resource_size(res)); + ret = PTR_ERR(addr); + drm_err(drm, "Failed to remap memory region %p, errno %d\n", + mr, ret); + return ret; + } + mr->hpa_base = res->start; + + drm_info(drm, "Registered device memory [%llx-%llx] to devm, remapped to %pr\n", + mr->dpa_base, mr->dpa_base + mr->usable_size, res); + return 0; +} +EXPORT_SYMBOL_GPL(drm_svm_register_mem_region); diff --git a/include/drm/drm_svm.h b/include/drm/drm_svm.h index b2397a9ff244..cb1edb6a993e 100644 --- a/include/drm/drm_svm.h +++ b/include/drm/drm_svm.h @@ -164,6 +164,8 @@ static inline u64 drm_mem_region_page_to_dpa(struct drm_mem_region *mr, struct p return dpa; } +int drm_svm_register_mem_region(const struct drm_device *drm, struct drm_mem_region *mr); + /** * struct drm_hmmptr- hmmptr pointer * -- 2.26.3