smb3: do not send compression info by default
Since in theory a server could respond with compressed read
responses even if not requested on read request (assuming that
a compression negcontext is sent in negotiate protocol) - do
not send compression information during negotiate protocol
unless the user asks for compression explicitly (compression
is experimental), and add a mount warning that compression
is experimental.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 07c9cd7..8ad8bbe 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_compress,
/* Mount options which take numeric value */
Opt_backupuid, Opt_backupgid, Opt_uid,
@@ -213,6 +214,7 @@ 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_compress, "compress=%s" },
{ Opt_blank_user, "user=" },
{ Opt_blank_user, "username=" },
@@ -1915,6 +1917,11 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
case Opt_rdma:
vol->rdma = true;
break;
+ case Opt_compress:
+ vol->compression = UNKNOWN_TYPE;
+ cifs_dbg(VFS,
+ "SMB3 compression support is experimental\n");
+ break;
/* Numeric Values */
case Opt_backupuid:
@@ -2691,6 +2698,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
tcp_ses->sequence_number = 0;
tcp_ses->reconnect_instance = 1;
tcp_ses->lstrp = jiffies;
+ tcp_ses->compress_algorithm = cpu_to_le16(volume_info->compression);
spin_lock_init(&tcp_ses->req_lock);
INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
INIT_LIST_HEAD(&tcp_ses->smb_ses_list);