From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id 601196B025E for ; Thu, 26 Jan 2017 12:10:02 -0500 (EST) Received: by mail-pf0-f200.google.com with SMTP id d123so65052468pfd.0 for ; Thu, 26 Jan 2017 09:10:02 -0800 (PST) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTPS id u88si1901346pfi.55.2017.01.26.09.10.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 26 Jan 2017 09:10:01 -0800 (PST) Subject: [PATCH v2 3/3] dax: Support for transparent PUD pages for device DAX From: Dave Jiang Date: Thu, 26 Jan 2017 10:10:00 -0700 Message-ID: <148545060002.17912.6765687780007547551.stgit@djiang5-desk3.ch.intel.com> In-Reply-To: <148545012634.17912.13951763606410303827.stgit@djiang5-desk3.ch.intel.com> References: <148545012634.17912.13951763606410303827.stgit@djiang5-desk3.ch.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: dave.hansen@linux.intel.com, mawilcox@microsoft.com, linux-nvdimm@lists.01.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, vbabka@suse.cz, jack@suse.com, dan.j.williams@intel.com, linux-ext4@vger.kernel.org, ross.zwisler@linux.intel.com, kirill.shutemov@linux.intel.com Adding transparent huge PUD pages support for device DAX by adding a pud_fault handler. Signed-off-by: Dave Jiang --- drivers/dax/dax.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c index 922ec46..b90bb30 100644 --- a/drivers/dax/dax.c +++ b/drivers/dax/dax.c @@ -493,6 +493,51 @@ static int __dax_dev_pmd_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) vmf->flags & FAULT_FLAG_WRITE); } +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD +static int __dax_dev_pud_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) +{ + unsigned long pud_addr = vmf->address & PUD_MASK; + struct device *dev = &dax_dev->dev; + struct dax_region *dax_region; + phys_addr_t phys; + pgoff_t pgoff; + pfn_t pfn; + + if (check_vma(dax_dev, vmf->vma, __func__)) + return VM_FAULT_SIGBUS; + + dax_region = dax_dev->region; + if (dax_region->align > PUD_SIZE) { + dev_dbg(dev, "%s: alignment > fault size\n", __func__); + return VM_FAULT_SIGBUS; + } + + /* dax pud mappings require pfn_t_devmap() */ + if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) != (PFN_DEV|PFN_MAP)) { + dev_dbg(dev, "%s: alignment > fault size\n", __func__); + return VM_FAULT_SIGBUS; + } + + pgoff = linear_page_index(vmf->vma, pud_addr); + phys = pgoff_to_phys(dax_dev, pgoff, PUD_SIZE); + if (phys == -1) { + dev_dbg(dev, "%s: phys_to_pgoff(%#lx) failed\n", __func__, + pgoff); + return VM_FAULT_SIGBUS; + } + + pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); + + return vmf_insert_pfn_pud(vmf->vma, vmf->address, vmf->pud, pfn, + vmf->flags & FAULT_FLAG_WRITE); +} +#else +static int __dax_dev_pud_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) +{ + return VM_FAULT_FALLBACK; +} +#endif /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ + static int dax_dev_fault(struct vm_fault *vmf) { int rc; @@ -512,6 +557,9 @@ static int dax_dev_fault(struct vm_fault *vmf) case FAULT_FLAG_SIZE_PMD: rc = __dax_dev_pmd_fault(dax_dev, vmf); break; + case FAULT_FLAG_SIZE_PUD: + rc = __dax_dev_pud_fault(dax_dev, vmf); + break; default: return VM_FAULT_FALLBACK; } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org