On Tue, Apr 9, 2019 at 3:42 PM 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.
>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
> fs/ceph/dir.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++---
> fs/ceph/file.c | 4 +++
> fs/ceph/super.h | 1 +
> 3 files changed, 66 insertions(+), 4 deletions(-)
>
> diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
> index 386c9439a020..0b8cee46e07c 100644
> --- a/fs/ceph/dir.c
> +++ b/fs/ceph/dir.c
> @@ -998,11 +998,16 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
> struct ceph_mds_request *req;
> int err;
>
> + dout("link in dir %p old_dentry %p dentry %p\n", dir,
> + old_dentry, dentry);
> +
> if (ceph_snap(dir) != CEPH_NOSNAP)
> return -EROFS;
>
> - dout("link in dir %p old_dentry %p dentry %p\n", dir,
> - old_dentry, dentry);
> + err = ceph_async_dirop_request_wait(dir);
> + if (err)
> + return err;
> +
> req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
> if (IS_ERR(req)) {
> d_drop(dentry);
> @@ -1041,6 +1046,43 @@ static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
> iput(req->r_old_inode);
> }
>
> +int ceph_async_dirop_request_wait(struct inode *inode)
> +{
> + struct ceph_inode_info *ci = ceph_inode(inode);
> + struct ceph_mds_request *req = NULL;
> + int ret = 0;
> +
> + /* Only applicable for directories */
> + if (S_ISDIR(inode->i_mode))
That should, of course, be !S_ISDIR(...
> + return 0;
> +
> + spin_lock(&ci->i_unsafe_lock);
> + if (!list_empty(&ci->i_unsafe_dirops)) {
> + struct ceph_mds_request *last;
> + last = list_last_entry(&ci->i_unsafe_dirops,
> + struct ceph_mds_request,
> + r_unsafe_dir_item);
> + /*
> + * If last request hasn't gotten a reply, then wait
> + * for it.
> + */
> + if (!test_bit(CEPH_MDS_R_GOT_UNSAFE, &last->r_req_flags) &&
> + !test_bit(CEPH_MDS_R_GOT_SAFE, &last->r_req_flags)) {
> + req = last;
> + ceph_mdsc_get_request(req);
> + }
> + }
> + spin_unlock(&ci->i_unsafe_lock);
> +
> + if (req) {
> + dout("%s %p wait on tid %llu\n", __func__, inode,
> + req ? req->r_tid : 0ULL);
> + ret = wait_for_completion_killable(&req->r_completion);
> + ceph_mdsc_put_request(req);
> + }
> + return ret;
> +}
> +
> /*
> * rmdir and unlink are differ only by the metadata op code
> */
> @@ -1064,6 +1106,12 @@ 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(dir);
> + if (err)
> + goto out;
> +
> req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
> if (IS_ERR(req)) {
> err = PTR_ERR(req);
> @@ -1115,6 +1163,9 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
> int op = CEPH_MDS_OP_RENAME;
> int err;
>
> + dout("rename dir %p dentry %p to dir %p dentry %p\n",
> + old_dir, old_dentry, new_dir, new_dentry);
> +
> if (flags)
> return -EINVAL;
>
> @@ -1131,8 +1182,14 @@ 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(old_dir);
> + if (err)
> + return err;
> +
> + err = ceph_async_dirop_request_wait(new_dir);
> + 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 f24d18f46715..f7e49907514e 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -444,6 +444,10 @@ 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 5c361dc1f47f..e97a6ce31a4e 100644
> --- a/fs/ceph/super.h
> +++ b/fs/ceph/super.h
> @@ -1070,6 +1070,7 @@ 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);
> --
> 2.20.1
>
--
Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
