From ca567eb2b3f014d5be0f44c6f68b01a522f15ca4 Mon Sep 17 00:00:00 2001 From: Steve French Date: Fri, 29 Mar 2019 16:31:07 -0500 Subject: SMB3: Allow persistent handle timeout to be configurable on mount Reconnecting after server or network failure can be improved (to maintain availability and protect data integrity) by allowing the client to choose the default persistent (or resilient) handle timeout in some use cases. Today we default to 0 which lets the server pick the default timeout (usually 120 seconds) but this can be problematic for some workloads. Add the new mount parameter to cifs.ko for SMB3 mounts "handletimeout" which enables the user to override the default handle timeout for persistent (mount option "persistenthandles") or resilient handles (mount option "resilienthandles"). Maximum allowed is 16 minutes (960000 ms). Units for the timeout are expressed in milliseconds. See section 2.2.14.2.12 and 2.2.31.3 of the MS-SMB2 protocol specification for more information. Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky Reviewed-by: Ronnie Sahlberg CC: Stable --- fs/cifs/smb2pdu.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'fs/cifs/smb2pdu.c') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 0dc66f36ff5b..21ad01d55ab2 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1859,8 +1859,9 @@ add_lease_context(struct TCP_Server_Info *server, struct kvec *iov, } static struct create_durable_v2 * -create_durable_v2_buf(struct cifs_fid *pfid) +create_durable_v2_buf(struct cifs_open_parms *oparms) { + struct cifs_fid *pfid = oparms->fid; struct create_durable_v2 *buf; buf = kzalloc(sizeof(struct create_durable_v2), GFP_KERNEL); @@ -1874,7 +1875,14 @@ create_durable_v2_buf(struct cifs_fid *pfid) (struct create_durable_v2, Name)); buf->ccontext.NameLength = cpu_to_le16(4); - buf->dcontext.Timeout = 0; /* Should this be configurable by workload */ + /* + * NB: Handle timeout defaults to 0, which allows server to choose + * (most servers default to 120 seconds) and most clients default to 0. + * This can be overridden at mount ("handletimeout=") if the user wants + * a different persistent (or resilient) handle timeout for all opens + * opens on a particular SMB3 mount. + */ + buf->dcontext.Timeout = cpu_to_le32(oparms->tcon->handle_timeout); buf->dcontext.Flags = cpu_to_le32(SMB2_DHANDLE_FLAG_PERSISTENT); generate_random_uuid(buf->dcontext.CreateGuid); memcpy(pfid->create_guid, buf->dcontext.CreateGuid, 16); @@ -1927,7 +1935,7 @@ add_durable_v2_context(struct kvec *iov, unsigned int *num_iovec, struct smb2_create_req *req = iov[0].iov_base; unsigned int num = *num_iovec; - iov[num].iov_base = create_durable_v2_buf(oparms->fid); + iov[num].iov_base = create_durable_v2_buf(oparms); if (iov[num].iov_base == NULL) return -ENOMEM; iov[num].iov_len = sizeof(struct create_durable_v2); -- cgit v1.2.3