Re: [PATCH v2 31/34] fs/nfs: convert put_page() to put_user_page*()

From: Calum Mackay <calum.mackay@oracle.com>
To: john.hubbard@gmail.com, Andrew Morton <akpm@linux-foundation.org>
Cc: "Christoph Hellwig" <hch@infradead.org>,
	"Dan Williams" <dan.j.williams@intel.com>,
	"Dave Chinner" <david@fromorbit.com>,
	"Dave Hansen" <dave.hansen@linux.intel.com>,
	"Ira Weiny" <ira.weiny@intel.com>, "Jan Kara" <jack@suse.cz>,
	"Jason Gunthorpe" <jgg@ziepe.ca>,
	"Jérôme Glisse" <jglisse@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	amd-gfx@lists.freedesktop.org, ceph-devel@vger.kernel.org,
	devel@driverdev.osuosl.org, devel@lists.orangefs.org,
	dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org,
	kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-block@vger.kernel.org, linux-crypto@vger.kernel.org,
	linux-fbdev@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-media@vger.kernel.org, linux-mm@kvack.org,
	linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org,
	linux-rpi-kernel@lists.infradead.org, linux-xfs@vger.kernel.org,
	netdev@vger.kernel.org, rds-devel@oss.oracle.com,
	sparclinux@vger.kernel.org, x86@kernel.org,
	xen-devel@lists.xenproject.org,
	"John Hubbard" <jhubbard@nvidia.com>,
	"Trond Myklebust" <trond.myklebust@hammerspace.com>,
	"Anna Schumaker" <anna.schumaker@netapp.com>
Subject: Re: [PATCH v2 31/34] fs/nfs: convert put_page() to put_user_page*()
Date: Mon, 5 Aug 2019 01:26:59 +0100	[thread overview]
Message-ID: <cf978e10-facc-ba5b-d7e4-d7fc2c3f7ebc@oracle.com> (raw)
In-Reply-To: <20190804224915.28669-32-jhubbard@nvidia.com>

On 04/08/2019 11:49 pm, john.hubbard@gmail.com wrote:
> From: John Hubbard <jhubbard@nvidia.com>
> 
> For pages that were retained via get_user_pages*(), release those pages
> via the new put_user_page*() routines, instead of via put_page() or
> release_pages().
> 
> This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
> ("mm: introduce put_user_page*(), placeholder versions").
> 
> Cc: Calum Mackay <calum.mackay@oracle.com>
> Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
> Cc: Anna Schumaker <anna.schumaker@netapp.com>
> Cc: linux-nfs@vger.kernel.org
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> ---
>   fs/nfs/direct.c | 11 ++---------
>   1 file changed, 2 insertions(+), 9 deletions(-)

Reviewed-by: Calum Mackay <calum.mackay@oracle.com>


> diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
> index 0cb442406168..c0c1b9f2c069 100644
> --- a/fs/nfs/direct.c
> +++ b/fs/nfs/direct.c
> @@ -276,13 +276,6 @@ ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
>   	return nfs_file_direct_write(iocb, iter);
>   }
>   
> -static void nfs_direct_release_pages(struct page **pages, unsigned int npages)
> -{
> -	unsigned int i;
> -	for (i = 0; i < npages; i++)
> -		put_page(pages[i]);
> -}
> -
>   void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
>   			      struct nfs_direct_req *dreq)
>   {
> @@ -512,7 +505,7 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
>   			pos += req_len;
>   			dreq->bytes_left -= req_len;
>   		}
> -		nfs_direct_release_pages(pagevec, npages);
> +		put_user_pages(pagevec, npages);
>   		kvfree(pagevec);
>   		if (result < 0)
>   			break;
> @@ -935,7 +928,7 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
>   			pos += req_len;
>   			dreq->bytes_left -= req_len;
>   		}
> -		nfs_direct_release_pages(pagevec, npages);
> +		put_user_pages(pagevec, npages);
>   		kvfree(pagevec);
>   		if (result < 0)
>   			break;
>