Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-wg0-f54.google.com ([74.125.82.54]:61506 "EHLO mail-wg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757334Ab3CUL10 (ORCPT ); Thu, 21 Mar 2013 07:27:26 -0400 Received: by mail-wg0-f54.google.com with SMTP id fm10so2214123wgb.9 for ; Thu, 21 Mar 2013 04:27:24 -0700 (PDT) Message-ID: <514AEE9A.3090907@tonian.com> Date: Thu, 21 Mar 2013 13:27:22 +0200 From: Benny Halevy MIME-Version: 1.0 To: Trond Myklebust CC: linux-nfs@vger.kernel.org, Boaz Harrosh , Peng Tao Subject: Re: [PATCH 3/3] NFSv4.1: Add a helper pnfs_commit_and_return_layout References: <1363801148-29998-1-git-send-email-Trond.Myklebust@netapp.com> <1363801148-29998-2-git-send-email-Trond.Myklebust@netapp.com> <1363801148-29998-3-git-send-email-Trond.Myklebust@netapp.com> In-Reply-To: <1363801148-29998-3-git-send-email-Trond.Myklebust@netapp.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 2013-03-20 19:39, Trond Myklebust wrote: > In order to be able to safely return the layout in nfs4_proc_setattr, > we need to block new uses of the layout, wait for all outstanding > users of the layout to complete, commit the layout and then return it. > > This patch adds a helper in order to do all this safely. > > Signed-off-by: Trond Myklebust > Cc: Boaz Harrosh > --- > fs/nfs/nfs4proc.c | 2 +- > fs/nfs/pnfs.c | 22 ++++++++++++++++++++++ > fs/nfs/pnfs.h | 6 ++++++ > 3 files changed, 29 insertions(+), 1 deletion(-) > > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > index 5122753..c560c8f 100644 > --- a/fs/nfs/nfs4proc.c > +++ b/fs/nfs/nfs4proc.c > @@ -2695,7 +2695,7 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, > int status; > > if (pnfs_ld_layoutret_on_setattr(inode)) > - pnfs_return_layout(inode); > + pnfs_commit_and_return_layout(inode); > > nfs_fattr_init(fattr); > > diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c > index 45badca..5a5e14d 100644 > --- a/fs/nfs/pnfs.c > +++ b/fs/nfs/pnfs.c > @@ -868,6 +868,28 @@ out: > } > EXPORT_SYMBOL_GPL(_pnfs_return_layout); > > +int > +pnfs_commit_and_return_layout(struct inode *inode) > +{ > + struct pnfs_layout_hdr *lo; > + int ret; > + > + spin_lock(&inode->i_lock); > + lo = NFS_I(inode)->layout; > + if (lo == NULL) { > + spin_unlock(&inode->i_lock); > + return 0; > + } > + /* Block new layoutgets and read/write to ds */ > + lo->plh_block_lgets++; > + spin_unlock(&inode->i_lock); > + filemap_fdatawait(inode->i_mapping); > + ret = pnfs_layoutcommit_inode(inode, true); > + if (ret == 0) > + ret = _pnfs_return_layout(inode); else { spin_lock(&inode->i_lock); lo->plh_block_lgets--; spin_unlock(&inode->i_lock); } ? Benny > + return ret; > +} > + > bool pnfs_roc(struct inode *ino) > { > struct pnfs_layout_hdr *lo; > diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h > index 94ba804..f5f8a47 100644 > --- a/fs/nfs/pnfs.h > +++ b/fs/nfs/pnfs.h > @@ -219,6 +219,7 @@ void pnfs_set_layoutcommit(struct nfs_write_data *wdata); > void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data); > int pnfs_layoutcommit_inode(struct inode *inode, bool sync); > int _pnfs_return_layout(struct inode *); > +int pnfs_commit_and_return_layout(struct inode *); > void pnfs_ld_write_done(struct nfs_write_data *); > void pnfs_ld_read_done(struct nfs_read_data *); > struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino, > @@ -407,6 +408,11 @@ static inline int pnfs_return_layout(struct inode *ino) > return 0; > } > > +static inline int pnfs_commit_and_return_layout(struct inode *inode) > +{ > + return 0; > +} > + > static inline bool > pnfs_ld_layoutret_on_setattr(struct inode *inode) > { >