From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751510AbeDYHJT (ORCPT ); Wed, 25 Apr 2018 03:09:19 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:46767 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750941AbeDYHJO (ORCPT ); Wed, 25 Apr 2018 03:09:14 -0400 X-Google-Smtp-Source: AB8JxZprzHe0kJZRd/Kk19eKWZn7ZTHnxuY0nHfyR++ytjH++HNVLmvfKezL0yEAknFBl3iAT+9mxw== Date: Wed, 25 Apr 2018 00:09:12 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Souptick Joarder cc: akpm@linux-foundation.org, zi.yan@cs.rutgers.edu, dan.j.williams@intel.com, kirill.shutemov@linux.intel.com, ross.zwisler@linux.intel.com, n-horiguchi@ah.jp.nec.com, mhocko@suse.com, shli@fb.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] mm: huge_memory: Change return type to vm_fault_t In-Reply-To: <20180425044326.GA21504@jordon-HP-15-Notebook-PC> Message-ID: References: <20180425044326.GA21504@jordon-HP-15-Notebook-PC> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 25 Apr 2018, Souptick Joarder wrote: > Use new return type vm_fault_t for fault handler. For > now, this is just documenting that the function returns > a VM_FAULT value rather than an errno. Once all instances > are converted, vm_fault_t will become a distinct type. > > Commit 1c8f422059ae ("mm: change return type to vm_fault_t") > > Signed-off-by: Souptick Joarder > Reviewed-by: Matthew Wilcox > --- > v2: Updated the change log > > include/linux/huge_mm.h | 5 +++-- > mm/huge_memory.c | 4 ++-- > 2 files changed, 5 insertions(+), 4 deletions(-) > > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > index a8a1262..d3bbf6b 100644 > --- a/include/linux/huge_mm.h > +++ b/include/linux/huge_mm.h > @@ -3,6 +3,7 @@ > #define _LINUX_HUGE_MM_H > > #include > +#include > > #include /* only for vma_is_dax() */ > > @@ -46,9 +47,9 @@ extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, > extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, > unsigned long addr, pgprot_t newprot, > int prot_numa); > -int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > +vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > pmd_t *pmd, pfn_t pfn, bool write); > -int vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > +vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > pud_t *pud, pfn_t pfn, bool write); > enum transparent_hugepage_flag { > TRANSPARENT_HUGEPAGE_FLAG, > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 87ab9b8..1fe4705 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -755,7 +755,7 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > spin_unlock(ptl); > } > > -int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > +vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > pmd_t *pmd, pfn_t pfn, bool write) > { > pgprot_t pgprot = vma->vm_page_prot; > @@ -815,7 +815,7 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > spin_unlock(ptl); > } > > -int vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > +vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > pud_t *pud, pfn_t pfn, bool write) > { > pgprot_t pgprot = vma->vm_page_prot; This isn't very useful unless functions that return the return value of these functions, __dev_dax_{pmd,pud}_fault(), recast it as an int. __dev_dax_pte_fault() would do the same thing, so it should logically also be vm_fault_t, so then you would convert dev_dax_huge_fault() and dev_dax_fault() as well in the same patch.