Return-Path: Received: from fieldses.org ([173.255.197.46]:48004 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750821AbdE3SCt (ORCPT ); Tue, 30 May 2017 14:02:49 -0400 Date: Tue, 30 May 2017 14:02:48 -0400 From: "J. Bruce Fields" To: Christoph Hellwig Cc: Alexander Viro , Jeff Layton , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 09/10] nfsd: use vfs_iter_read/write Message-ID: <20170530180248.GH18523@fieldses.org> References: <20170527081654.15957-1-hch@lst.de> <20170527081654.15957-10-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170527081654.15957-10-hch@lst.de> Sender: linux-nfs-owner@vger.kernel.org List-ID: ACK.--b. On Sat, May 27, 2017 at 11:16:53AM +0300, Christoph Hellwig wrote: > Instead of messing with the address limit to use vfs_read/vfs_writev. > > Note that this requires that exported file implement ->read_iter and > ->write_iter. All currently exportable file systems do this. > > Signed-off-by: Christoph Hellwig > --- > fs/nfsd/vfs.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 2be32955d7f2..37a03c456b38 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -911,13 +911,12 @@ __be32 nfsd_splice_read(struct svc_rqst *rqstp, > __be32 nfsd_readv(struct file *file, loff_t offset, struct kvec *vec, int vlen, > unsigned long *count) > { > - mm_segment_t oldfs; > + struct iov_iter iter; > int host_err; > > - oldfs = get_fs(); > - set_fs(KERNEL_DS); > - host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset, 0); > - set_fs(oldfs); > + iov_iter_kvec(&iter, READ | ITER_KVEC, vec, vlen, *count); > + host_err = vfs_iter_read(file, &iter, &offset, 0); > + > return nfsd_finish_read(file, count, host_err); > } > > @@ -974,7 +973,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, > unsigned long *cnt, int stable) > { > struct svc_export *exp; > - mm_segment_t oldfs; > + struct iov_iter iter; > __be32 err = 0; > int host_err; > int use_wgather; > @@ -1000,10 +999,8 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, > if (stable && !use_wgather) > flags |= RWF_SYNC; > > - /* Write the data. */ > - oldfs = get_fs(); set_fs(KERNEL_DS); > - host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos, flags); > - set_fs(oldfs); > + iov_iter_kvec(&iter, WRITE | ITER_KVEC, vec, vlen, *cnt); > + host_err = vfs_iter_write(file, &iter, &pos, flags); > if (host_err < 0) > goto out_nfserr; > *cnt = host_err; > -- > 2.11.0