On Tue, Jan 7, 2020 at 10:50 PM Yan, Zheng <ukernel@xxxxxxxxx> wrote:
>
> On Fri, Aug 2, 2019 at 4:26 AM Jeff Layton <jlayton@xxxxxxxxxx> wrote:
> >
> > Ensure that we wait on replies from any pending directory operations
> > involving children before we allow synchronous operations involving
> > that directory to proceed.
> >
>
> This patch is not needed because mds does the job. For current
> implementation, we need to make inode operations (getattr/setattr/...)
> wait until getting reply for async create.
>
I think about this again. Maybe it's better to do all these waits in MDS
>
> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > ---
> > fs/ceph/dir.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++--
> > fs/ceph/file.c | 4 ++++
> > fs/ceph/super.h | 1 +
> > 3 files changed, 51 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
> > index aab29f48c62d..35797ff895e7 100644
> > --- a/fs/ceph/dir.c
> > +++ b/fs/ceph/dir.c
> > @@ -1036,6 +1036,38 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
> > return err;
> > }
> >
> > +int ceph_async_dirop_request_wait(struct inode *inode)
> > +{
> > + struct ceph_inode_info *ci = ceph_inode(inode);
> > + struct ceph_mds_request *cur, *req;
> > + int ret = 0;
> > +
> > + /* Only applicable for directories */
> > + if (!inode || !S_ISDIR(inode->i_mode))
> > + return 0;
> > +retry:
> > + spin_lock(&ci->i_unsafe_lock);
> > + req = NULL;
> > + list_for_each_entry(cur, &ci->i_unsafe_dirops, r_unsafe_dir_item) {
> > + if (!test_bit(CEPH_MDS_R_GOT_UNSAFE, &cur->r_req_flags) &&
> > + !test_bit(CEPH_MDS_R_GOT_SAFE, &cur->r_req_flags)) {
> > + req = cur;
> > + ceph_mdsc_get_request(req);
> > + break;
> > + }
> > + }
> > + spin_unlock(&ci->i_unsafe_lock);
> > + if (req) {
> > + dout("%s %lx wait on tid %llu\n", __func__, inode->i_ino,
> > + req->r_tid);
> > + ret = wait_for_completion_killable(&req->r_completion);
> > + ceph_mdsc_put_request(req);
> > + if (!ret)
> > + goto retry;
> > + }
> > + return ret;
> > +}
> > +
> > /*
> > * rmdir and unlink are differ only by the metadata op code
> > */
> > @@ -1059,6 +1091,12 @@ static int ceph_unlink(struct inode *dir, struct dentry *dentry)
> > CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
> > } else
> > goto out;
> > +
> > + /* Wait for any requests involving children to get a reply */
> > + err = ceph_async_dirop_request_wait(inode);
> > + if (err)
> > + goto out;
> > +
> > req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
> > if (IS_ERR(req)) {
> > err = PTR_ERR(req);
> > @@ -1105,8 +1143,14 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
> > (!ceph_quota_is_same_realm(old_dir, new_dir)))
> > return -EXDEV;
> >
> > - dout("rename dir %p dentry %p to dir %p dentry %p\n",
> > - old_dir, old_dentry, new_dir, new_dentry);
> > + err = ceph_async_dirop_request_wait(d_inode(old_dentry));
> > + if (err)
> > + return err;
> > +
> > + err = ceph_async_dirop_request_wait(d_inode(new_dentry));
> > + if (err)
> > + return err;
> > +
> > req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
> > if (IS_ERR(req))
> > return PTR_ERR(req);
> > diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> > index 3c0b5247818f..75bce889305c 100644
> > --- a/fs/ceph/file.c
> > +++ b/fs/ceph/file.c
> > @@ -449,6 +449,10 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
> > dir, dentry, dentry,
> > d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
> >
> > + err = ceph_async_dirop_request_wait(dir);
> > + if (err)
> > + return err;
> > +
> > if (dentry->d_name.len > NAME_MAX)
> > return -ENAMETOOLONG;
> >
> > diff --git a/fs/ceph/super.h b/fs/ceph/super.h
> > index a9aa3e358226..77ed6c5900be 100644
> > --- a/fs/ceph/super.h
> > +++ b/fs/ceph/super.h
> > @@ -1113,6 +1113,7 @@ extern int ceph_handle_snapdir(struct ceph_mds_request *req,
> > struct dentry *dentry, int err);
> > extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
> > struct dentry *dentry, int err);
> > +extern int ceph_async_dirop_request_wait(struct inode *inode);
> >
> > extern void __ceph_dentry_lease_touch(struct ceph_dentry_info *di);
> > extern void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di);
> > --
> > 2.21.0
> >
