Re: [PATCH v8 23/26] mm/gup: pass flags arg to __gup_device_* functions

From: Jan Kara <jack@suse.cz>
To: John Hubbard <jhubbard@nvidia.com>
Cc: "Andrew Morton" <akpm@linux-foundation.org>,
	"Al Viro" <viro@zeniv.linux.org.uk>,
	"Alex Williamson" <alex.williamson@redhat.com>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
	"Björn Töpel" <bjorn.topel@intel.com>,
	"Christoph Hellwig" <hch@infradead.org>,
	"Dan Williams" <dan.j.williams@intel.com>,
	"Daniel Vetter" <daniel@ffwll.ch>,
	"Dave Chinner" <david@fromorbit.com>,
	"David Airlie" <airlied@linux.ie>,
	"David S . Miller" <davem@davemloft.net>,
	"Ira Weiny" <ira.weiny@intel.com>, "Jan Kara" <jack@suse.cz>,
	"Jason Gunthorpe" <jgg@ziepe.ca>, "Jens Axboe" <axboe@kernel.dk>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Jérôme Glisse" <jglisse@redhat.com>,
	"Magnus Karlsson" <magnus.karlsson@intel.com>,
	"Mauro Carvalho Chehab" <mchehab@kernel.org>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Michal Hocko" <mhocko@suse.com>,
	"Mike Kravetz" <mike.kravetz@oracle.com>,
	"Paul Mackerras" <paulus@samba.org>,
	"Shuah Khan" <shuah@kernel.org>,
	"Vlastimil Babka" <vbabka@suse.cz>,
	bpf@vger.kernel.org, dri-devel@lists.freedesktop.org,
	kvm@vger.kernel.org, linux-block@vger.kernel.org,
	linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org,
	linux-rdma@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
	netdev@vger.kernel.org, linux-mm@kvack.org,
	LKML <linux-kernel@vger.kernel.org>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Subject: Re: [PATCH v8 23/26] mm/gup: pass flags arg to __gup_device_* functions
Date: Tue, 10 Dec 2019 13:49:57 +0100	[thread overview]
Message-ID: <20191210124957.GG1551@quack2.suse.cz> (raw)
In-Reply-To: <20191209225344.99740-24-jhubbard@nvidia.com>

On Mon 09-12-19 14:53:41, John Hubbard wrote:
> A subsequent patch requires access to gup flags, so pass the flags
> argument through to the __gup_device_* functions.
> 
> Also placate checkpatch.pl by shortening a nearby line.
> 
> TODO: Christoph Hellwig requested folding this into the patch the uses
> the gup flags arguments.

You should probably implement this TODO? :)

								Honza

> 
> Reviewed-by: Jan Kara <jack@suse.cz>
> Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
> Reviewed-by: Ira Weiny <ira.weiny@intel.com>
> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> ---
>  mm/gup.c | 28 ++++++++++++++++++----------
>  1 file changed, 18 insertions(+), 10 deletions(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index 73aedcefa4bd..687d48506f04 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -1957,7 +1957,8 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
>  
>  #if defined(CONFIG_ARCH_HAS_PTE_DEVMAP) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
>  static int __gup_device_huge(unsigned long pfn, unsigned long addr,
> -		unsigned long end, struct page **pages, int *nr)
> +			     unsigned long end, unsigned int flags,
> +			     struct page **pages, int *nr)
>  {
>  	int nr_start = *nr;
>  	struct dev_pagemap *pgmap = NULL;
> @@ -1983,13 +1984,14 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
>  }
>  
>  static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
> -		unsigned long end, struct page **pages, int *nr)
> +				 unsigned long end, unsigned int flags,
> +				 struct page **pages, int *nr)
>  {
>  	unsigned long fault_pfn;
>  	int nr_start = *nr;
>  
>  	fault_pfn = pmd_pfn(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
> -	if (!__gup_device_huge(fault_pfn, addr, end, pages, nr))
> +	if (!__gup_device_huge(fault_pfn, addr, end, flags, pages, nr))
>  		return 0;
>  
>  	if (unlikely(pmd_val(orig) != pmd_val(*pmdp))) {
> @@ -2000,13 +2002,14 @@ static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
>  }
>  
>  static int __gup_device_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
> -		unsigned long end, struct page **pages, int *nr)
> +				 unsigned long end, unsigned int flags,
> +				 struct page **pages, int *nr)
>  {
>  	unsigned long fault_pfn;
>  	int nr_start = *nr;
>  
>  	fault_pfn = pud_pfn(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
> -	if (!__gup_device_huge(fault_pfn, addr, end, pages, nr))
> +	if (!__gup_device_huge(fault_pfn, addr, end, flags, pages, nr))
>  		return 0;
>  
>  	if (unlikely(pud_val(orig) != pud_val(*pudp))) {
> @@ -2017,14 +2020,16 @@ static int __gup_device_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
>  }
>  #else
>  static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
> -		unsigned long end, struct page **pages, int *nr)
> +				 unsigned long end, unsigned int flags,
> +				 struct page **pages, int *nr)
>  {
>  	BUILD_BUG();
>  	return 0;
>  }
>  
>  static int __gup_device_huge_pud(pud_t pud, pud_t *pudp, unsigned long addr,
> -		unsigned long end, struct page **pages, int *nr)
> +				 unsigned long end, unsigned int flags,
> +				 struct page **pages, int *nr)
>  {
>  	BUILD_BUG();
>  	return 0;
> @@ -2136,7 +2141,8 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
>  	if (pmd_devmap(orig)) {
>  		if (unlikely(flags & FOLL_LONGTERM))
>  			return 0;
> -		return __gup_device_huge_pmd(orig, pmdp, addr, end, pages, nr);
> +		return __gup_device_huge_pmd(orig, pmdp, addr, end, flags,
> +					     pages, nr);
>  	}
>  
>  	page = pmd_page(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
> @@ -2157,7 +2163,8 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
>  }
>  
>  static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
> -		unsigned long end, unsigned int flags, struct page **pages, int *nr)
> +			unsigned long end, unsigned int flags,
> +			struct page **pages, int *nr)
>  {
>  	struct page *head, *page;
>  	int refs;
> @@ -2168,7 +2175,8 @@ static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr,
>  	if (pud_devmap(orig)) {
>  		if (unlikely(flags & FOLL_LONGTERM))
>  			return 0;
> -		return __gup_device_huge_pud(orig, pudp, addr, end, pages, nr);
> +		return __gup_device_huge_pud(orig, pudp, addr, end, flags,
> +					     pages, nr);
>  	}
>  
>  	page = pud_page(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
> -- 
> 2.24.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR