From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id 8A3796B0003 for ; Wed, 25 Apr 2018 03:09:15 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id v14so10269118pgq.11 for ; Wed, 25 Apr 2018 00:09:15 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id o30-v6sor1314343pli.98.2018.04.25.00.09.14 for (Google Transport Security); Wed, 25 Apr 2018 00:09:14 -0700 (PDT) Date: Wed, 25 Apr 2018 00:09:12 -0700 (PDT) From: David Rientjes 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> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: 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 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.