From: Long Li <[email protected]> On write I/O finish, deregister the memory region if this was for a RDMA read. The call to smbd_deregister_mr will do local invalidation and possibly wait, if remote invalidate is not used.
Signed-off-by: Long Li <[email protected]> --- fs/cifs/smb2pdu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 5581afd..5551053 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -2666,6 +2666,18 @@ smb2_writev_callback(struct mid_q_entry *mid) break; } + /* + * If this wdata has a memory registered, the MR can be freed + * The number of MRs available is limited, it's important to recover + * used MR as soon as I/O is finished. Hold MR longer in the later + * I/O process can possibly result in I/O deadlock due to lack of MR + * to send request on I/O retry + */ + if (wdata->mr) { + smbd_deregister_mr(wdata->mr); + wdata->mr = NULL; + } + if (wdata->result) cifs_stats_fail_inc(tcon, SMB2_WRITE_HE); -- 2.7.4
