From: Aurelien Aptel <aaptel@suse.com>
Date: Fri, 20 Sep 2019 04:32:20 +0200
Subject: [PATCH] cifs: add multichannel mount options and data structs
Git-commit: bcc8880115bcb36bc281c7f4895a12b51569d8d4
Patch-mainline: v5.5-rc1
References: bsc#1192606
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>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/cifsfs.c | 4 ++++
fs/cifs/cifsglob.h | 16 ++++++++++++++++
fs/cifs/connect.c | 38 ++++++++++++++++++++++++++++++++++++--
3 files changed, 56 insertions(+), 2 deletions(-)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -594,6 +594,10 @@ cifs_show_options(struct seq_file *s, st
/* convert actimeo and display it in seconds */
seq_printf(s, ",actimeo=%lu", cifs_sb->actimeo / HZ);
+ if (tcon->ses->chan_max > 1)
+ seq_printf(s, ",multichannel,max_channel=%zu",
+ tcon->ses->chan_max);
+
return 0;
}
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -591,6 +591,10 @@ struct smb_vol {
bool resilient:1; /* noresilient not required since not fored for CA */
bool domainauto:1;
bool rdma:1;
+ bool multichannel:1;
+ bool use_client_guid:1;
+ /* reuse existing guid for multichannel */
+ u8 client_guid[SMB2_CLIENT_GUID_SIZE];
unsigned int bsize;
unsigned int rsize;
unsigned int wsize;
@@ -607,6 +611,7 @@ struct smb_vol {
__u64 snapshot_time; /* needed for timewarp tokens */
__u32 handle_timeout; /* persistent and durable handle timeout in ms */
unsigned int max_credits; /* smb3 max_credits 10 < credits < 60000 */
+ unsigned int max_channels;
__u16 compression; /* compression algorithm 0xFFFF default 0=disabled */
};
@@ -951,6 +956,11 @@ struct cifs_server_iface {
struct sockaddr_storage sockaddr;
};
+struct cifs_chan {
+ struct TCP_Server_Info *server;
+ __u8 signkey[SMB3_SIGN_KEY_SIZE];
+};
+
/*
* Session structure. One of these for each uid session with a particular host
*/
@@ -1000,6 +1010,12 @@ struct cifs_ses {
struct cifs_server_iface *iface_list;
size_t iface_count;
unsigned long iface_last_update; /* jiffies */
+
+#define CIFS_MAX_CHANNELS 16
+ struct cifs_chan chans[CIFS_MAX_CHANNELS];
+ size_t chan_count;
+ size_t chan_max;
+ atomic_t chan_seq; /* round robin state */
};
static inline bool
--- 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_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_op
{ 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_op
{ 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=" },
@@ -1680,6 +1684,10 @@ cifs_parse_mount_options(const char *mou
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;
@@ -1968,6 +1976,12 @@ cifs_parse_mount_options(const char *mou
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,
@@ -2131,6 +2145,15 @@ cifs_parse_mount_options(const char *mou
}
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 */
@@ -2774,7 +2797,11 @@ cifs_get_tcp_session(struct smb_vol *vol
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
@@ -2863,6 +2890,13 @@ static int match_session(struct cifs_ses
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))