+ * Apply the layout to the inode. Layout lock is held and will be released
+ * in this function.
+ */
+static int ll_layout_lock_set(struct lustre_handle *lockh, ldlm_mode_t mode,
+ struct inode *inode, __u32 *gen, bool reconf)
+{
+ struct ll_inode_info *lli = ll_i2info(inode);
+ struct ll_sb_info *sbi = ll_i2sbi(inode);
+ struct ldlm_lock *lock;
+ struct lustre_md md = { NULL };
+ struct cl_object_conf conf;
+ int rc = 0;
+ bool lvb_ready;
+ ENTRY;
+
+ LASSERT(lustre_handle_is_used(lockh));
+
+ lock = ldlm_handle2lock(lockh);
+ LASSERT(lock != NULL);
+ LASSERT(ldlm_has_layout(lock));
+
+ LDLM_DEBUG(lock, "File %p/"DFID" being reconfigured: %d.\n",
+ inode, PFID(&lli->lli_fid), reconf);
+
+ lock_res_and_lock(lock);
+ lvb_ready = !!(lock->l_flags & LDLM_FL_LVB_READY);
+ unlock_res_and_lock(lock);
+ /* checking lvb_ready is racy but this is okay. The worst case is
+ * that multi processes may configure the file on the same time. */
+ if (lvb_ready || !reconf) {
+ LDLM_LOCK_PUT(lock);
+
+ rc = -ENODATA;
+ if (lvb_ready) {
+ /* layout_gen must be valid if layout lock is not
+ * cancelled and stripe has already set */
+ *gen = lli->lli_layout_gen;
+ rc = 0;
+ }
+ ldlm_lock_decref(lockh, mode);
+ RETURN(rc);
+ }
+
+ /* for layout lock, lmm is returned in lock's lvb.
+ * lvb_data is immutable if the lock is held so it's safe to access it
+ * without res lock. See the description in ldlm_lock_decref_internal()
+ * for the condition to free lvb_data of layout lock */
+ if (lock->l_lvb_data != NULL) {
+ rc = obd_unpackmd(sbi->ll_dt_exp, &md.lsm,
+ lock->l_lvb_data, lock->l_lvb_len);
+ if (rc >= 0) {
+ if (md.lsm != NULL)
+ *gen = md.lsm->lsm_layout_gen;
+ rc = 0;
+ } else {
+ CERROR("%s: file "DFID" unpackmd error: %d\n",
+ ll_get_fsname(inode->i_sb, NULL, 0),
+ PFID(&lli->lli_fid), rc);
+ }
+ }
+ if (rc < 0) {
+ LDLM_LOCK_PUT(lock);
+ ldlm_lock_decref(lockh, mode);
+ RETURN(rc);
+ }
+
+ /* set layout to file. Unlikely this will fail as old layout was
+ * surely eliminated */
+ memset(&conf, 0, sizeof conf);
+ conf.coc_opc = OBJECT_CONF_SET;
+ conf.coc_inode = inode;
+ conf.coc_lock = lock;
+ conf.u.coc_md = &md;
+ rc = ll_layout_conf(inode, &conf);
+ LDLM_LOCK_PUT(lock);
+
+ ldlm_lock_decref(lockh, mode);
+
+ if (md.lsm != NULL)
+ obd_free_memmd(sbi->ll_dt_exp, &md.lsm);
+
+ /* wait for IO to complete if it's still being used. */
+ if (rc == -EBUSY) {
+ CDEBUG(D_INODE, "%s: %p/"DFID" wait for layout reconf.\n",
+ ll_get_fsname(inode->i_sb, NULL, 0),
+ inode, PFID(&lli->lli_fid));
+
+ memset(&conf, 0, sizeof conf);
+ conf.coc_opc = OBJECT_CONF_WAIT;
+ conf.coc_inode = inode;
+ rc = ll_layout_conf(inode, &conf);
+ if (rc == 0)
+ rc = -EAGAIN;
+
+ CDEBUG(D_INODE, "file: "DFID" waiting layout return: %d.\n",
+ PFID(&lli->lli_fid), rc);
+ }
+
+ RETURN(rc);
+}
+
+/**