cifs: add multichannel mount options and data structs
adds:
- [no]multichannel to enable/disable multichannel
- max_channels=N to control how many channels to create
these options are then stored in the volume struct.
- store channels and max_channels in cifs_ses
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index a7a0267..1a7d14a 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -97,6 +97,7 @@ enum {
Opt_persistent, Opt_nopersistent,
Opt_resilient, Opt_noresilient,
Opt_domainauto, Opt_rdma, Opt_modesid, Opt_rootfs,
+ Opt_multichannel, Opt_nomultichannel,
Opt_compress,
/* Mount options which take numeric value */
@@ -106,7 +107,7 @@ enum {
Opt_min_enc_offload,
Opt_blocksize, Opt_rsize, Opt_wsize, Opt_actimeo,
Opt_echo_interval, Opt_max_credits, Opt_handletimeout,
- Opt_snapshot,
+ Opt_snapshot, Opt_max_channels,
/* Mount options which take string value */
Opt_user, Opt_pass, Opt_ip,
@@ -199,6 +200,8 @@ static const match_table_t cifs_mount_option_tokens = {
{ Opt_noresilient, "noresilienthandles"},
{ Opt_domainauto, "domainauto"},
{ Opt_rdma, "rdma"},
+ { Opt_multichannel, "multichannel" },
+ { Opt_nomultichannel, "nomultichannel" },
{ Opt_backupuid, "backupuid=%s" },
{ Opt_backupgid, "backupgid=%s" },
@@ -218,6 +221,7 @@ static const match_table_t cifs_mount_option_tokens = {
{ Opt_echo_interval, "echo_interval=%s" },
{ Opt_max_credits, "max_credits=%s" },
{ Opt_snapshot, "snapshot=%s" },
+ { Opt_max_channels, "max_channels=%s" },
{ Opt_compress, "compress=%s" },
{ Opt_blank_user, "user=" },
@@ -1681,6 +1685,10 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
+ /* default to no multichannel (single server connection) */
+ vol->multichannel = false;
+ vol->max_channels = 1;
+
if (!mountdata)
goto cifs_parse_mount_err;
@@ -1974,6 +1982,12 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
case Opt_rdma:
vol->rdma = true;
break;
+ case Opt_multichannel:
+ vol->multichannel = true;
+ break;
+ case Opt_nomultichannel:
+ vol->multichannel = false;
+ break;
case Opt_compress:
vol->compression = UNKNOWN_TYPE;
cifs_dbg(VFS,
@@ -2137,6 +2151,15 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
}
vol->max_credits = option;
break;
+ case Opt_max_channels:
+ if (get_option_ul(args, &option) || option < 1 ||
+ option > CIFS_MAX_CHANNELS) {
+ cifs_dbg(VFS, "%s: Invalid max_channels value, needs to be 1-%d\n",
+ __func__, CIFS_MAX_CHANNELS);
+ goto cifs_parse_mount_err;
+ }
+ vol->max_channels = option;
+ break;
/* String Arguments */
@@ -2781,7 +2804,11 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
sizeof(tcp_ses->srcaddr));
memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
sizeof(tcp_ses->dstaddr));
- generate_random_uuid(tcp_ses->client_guid);
+ if (volume_info->use_client_guid)
+ memcpy(tcp_ses->client_guid, volume_info->client_guid,
+ SMB2_CLIENT_GUID_SIZE);
+ else
+ generate_random_uuid(tcp_ses->client_guid);
/*
* at this point we are the only ones with the pointer
* to the struct since the kernel thread not created yet
@@ -2870,6 +2897,13 @@ static int match_session(struct cifs_ses *ses, struct smb_vol *vol)
vol->sectype != ses->sectype)
return 0;
+ /*
+ * If an existing session is limited to less channels than
+ * requested, it should not be reused
+ */
+ if (ses->chan_max < vol->max_channels)
+ return 0;
+
switch (ses->sectype) {
case Kerberos:
if (!uid_eq(vol->cred_uid, ses->cred_uid))