From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junxiao Bi Date: Wed, 6 Jan 2016 12:41:51 +0800 Subject: [Ocfs2-devel] [PATCH] revert to using ocfs2_acl_chmod to avoid inode cluster lock hang In-Reply-To: <1452047231-30569-1-git-send-email-tariq.x.saeed@oracle.com> References: <1452047231-30569-1-git-send-email-tariq.x.saeed@oracle.com> Message-ID: <568C9B0F.7040500@oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Hi Tariq, On 01/06/2016 10:27 AM, Tariq Saeed wrote: > Orabug: 21793017 > > commit 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()") > introduced this issue. ocfs2_setattr called by chmod command > holds cluster wide inode lock (Orabug 21685187) when calling > posix_acl_chmod. This latter function in turn calls ocfs2_iop_get_acl > and ocfs2_iop_set_acl. These two are also called directly from vfs > layer for getfacl/setfacl commands and therefore acquire the cluster wide > inode lock. If a remote conversion request comes after the first inode > lock in ocfs2_setattr, OCFS2_LOCK_BLOCKED will be set in l_flags. This > will cause the second call to inode lock from the ocfs2_iop_get_acl() > to block indefinetly. This fixed part of the deadlock. There is another part. ocfs2_mknod()->posix_acl_create()->ocfs2_iop_get_acl() Thanks, Junxiao. > > To solve this, we need to use nolock version of getacl. Since > nolock version of posix_acl_chmod does not exist, we restore a slightly > modified version of ocfs2_acl_chmod, which was removed in > commit 702e5bc68ad2 ("ocfs2: use generic posix ACL infrastructure") > that uses nolock version of getacl. > > Signed-off-by: Tariq Saeed > --- > fs/ocfs2/acl.c | 25 +++++++++++++++++++++++++ > fs/ocfs2/acl.h | 1 + > fs/ocfs2/file.c | 4 ++-- > 3 files changed, 28 insertions(+), 2 deletions(-) > > diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c > index 0cdf497..0fbd18c 100644 > --- a/fs/ocfs2/acl.c > +++ b/fs/ocfs2/acl.c > @@ -322,3 +322,28 @@ struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type) > brelse(di_bh); > return acl; > } > + > +int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh) > +{ > + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); > + struct posix_acl *acl; > + int ret; > + > + if (S_ISLNK(inode->i_mode)) > + return -EOPNOTSUPP; > + > + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) > + return 0; > + > + acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh); > + if (IS_ERR(acl) || !acl) > + return PTR_ERR(acl); > + ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode); > + if (ret) > + return ret; > + ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS, > + acl, NULL, NULL); > + posix_acl_release(acl); > + return ret; > +} > + > diff --git a/fs/ocfs2/acl.h b/fs/ocfs2/acl.h > index 3fce68d..035e587 100644 > --- a/fs/ocfs2/acl.h > +++ b/fs/ocfs2/acl.h > @@ -35,5 +35,6 @@ int ocfs2_set_acl(handle_t *handle, > struct posix_acl *acl, > struct ocfs2_alloc_context *meta_ac, > struct ocfs2_alloc_context *data_ac); > +extern int ocfs2_acl_chmod(struct inode *, struct buffer_head *); > > #endif /* OCFS2_ACL_H */ > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c > index 0e5b451..77d30cb 100644 > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1268,20 +1268,20 @@ bail_unlock_rw: > if (size_change) > ocfs2_rw_unlock(inode, 1); > bail: > - brelse(bh); > > /* Release quota pointers in case we acquired them */ > for (qtype = 0; qtype < OCFS2_MAXQUOTAS; qtype++) > dqput(transfer_to[qtype]); > > if (!status && attr->ia_valid & ATTR_MODE) { > - status = posix_acl_chmod(inode, inode->i_mode); > + status = ocfs2_acl_chmod(inode, bh); > if (status < 0) > mlog_errno(status); > } > if (inode_locked) > ocfs2_inode_unlock(inode, 1); > > + brelse(bh); > return status; > } > >