- mutex_lock(&ei->truncate_mutex);
-
- /*
- * If the indirect block is missing while we are reading
- * the chain(ext4_get_branch() returns -EAGAIN err), or
- * if the chain has been changed after we grab the semaphore,
- * (either because another process truncated this branch, or
- * another get_block allocated this branch) re-grab the chain to see if
- * the request block has been allocated or not.
- *
- * Since we already block the truncate/other get_block
- * at this point, we will have the current copy of the chain when we
- * splice the branch into the tree.
- */
- if (err == -EAGAIN || !verify_chain(chain, partial)) {
- while (partial > chain) {
- brelse(partial->bh);
- partial--;
- }
- partial = ext4_get_branch(inode, depth, offsets, chain, &err);
- if (!partial) {
- count++;
- mutex_unlock(&ei->truncate_mutex);
- if (err)
- goto cleanup;
- clear_buffer_new(bh_result);
- goto got_it;
- }
- }
-