Since many servers (Windows clients, and non-clustered servers) do not support persistent handles but do support resilient handles, allow the user to specify a mount option "resilienthandles" in order to get more reliable connections and less chance of data loss (at least when SMB2.1 or later)
Signed-off-by: Steve French <[email protected]> Signed-off-by: Steve French <[email protected]> --- fs/cifs/cifsfs.c | 2 ++ fs/cifs/cifsglob.h | 2 ++ fs/cifs/connect.c | 24 +++++++++++++++++++++++- fs/cifs/smb2file.c | 6 ++++++ 4 files changed, 33 insertions(+), 1 deletion(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 13302e9..f578ef9 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -456,6 +456,8 @@ cifs_show_options(struct seq_file *s, struct dentry *root) seq_puts(s, ",hard"); if (tcon->use_persistent) seq_puts(s, ",persistenthandles"); + else if (tcon->use_resilient) + seq_puts(s, ",resilienthandles"); if (tcon->unix_ext) seq_puts(s, ",unix"); else diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index ec31a03..472daeb 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -496,6 +496,7 @@ struct smb_vol { bool nosharesock:1; bool persistent:1; bool nopersistent:1; + bool resilient:1; /* noresilient not required since not fored for CA */ unsigned int rsize; unsigned int wsize; bool sockopt_tcp_nodelay:1; @@ -901,6 +902,7 @@ struct cifs_tcon { bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */ bool broken_sparse_sup; /* if server or share does not support sparse */ bool need_reconnect:1; /* connection reset, tid now invalid */ + bool use_resilient:1; /* use resilient instead of durable handles */ bool use_persistent:1; /* use persistent instead of durable handles */ #ifdef CONFIG_CIFS_SMB2 bool print:1; /* set if connection to printer share */ diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 9e44532..1e7840a 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -88,6 +88,7 @@ enum { Opt_fsc, Opt_mfsymlinks, Opt_multiuser, Opt_sloppy, Opt_nosharesock, Opt_persistent, Opt_nopersistent, + Opt_resilient, Opt_noresilient, /* Mount options which take numeric value */ Opt_backupuid, Opt_backupgid, Opt_uid, @@ -172,6 +173,8 @@ static const match_table_t cifs_mount_option_tokens = { { Opt_nosharesock, "nosharesock" }, { Opt_persistent, "persistenthandles"}, { Opt_nopersistent, "nopersistenthandles"}, + { Opt_resilient, "resilienthandles"}, + { Opt_noresilient, "noresilienthandles"}, { Opt_backupuid, "backupuid=%s" }, { Opt_backupgid, "backupgid=%s" }, @@ -1510,12 +1513,23 @@ cifs_parse_mount_options(const char *mountdata, const char *devname, break; case Opt_persistent: vol->persistent = true; - if (vol->nopersistent) { + if ((vol->nopersistent) || (vol->resilient)) { cifs_dbg(VFS, "persistenthandles mount options conflict\n"); goto cifs_parse_mount_err; } break; + case Opt_resilient: + vol->resilient = true; + if (vol->persistent) { + cifs_dbg(VFS, + "persistenthandles mount options conflict\n"); + goto cifs_parse_mount_err; + } + break; + case Opt_noresilient: + vol->resilient = false; /* this is already the default */ + break; /* Numeric Values */ case Opt_backupuid: @@ -2695,6 +2709,14 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info) && (volume_info->nopersistent == false)) { cifs_dbg(FYI, "enabling persistent handles\n"); tcon->use_persistent = true; + } else if (volume_info->resilient) { + if (ses->server->vals->protocol_id == 0) { + cifs_dbg(VFS, + "SMB2.1 or later required for resilient handles\n"); + rc = -EOPNOTSUPP; + goto out_fail; + } + tcon->use_resilient = true; } /* diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c index 2ab297d..04f2af0 100644 --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -67,6 +67,12 @@ smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, if (rc) goto out; + /* + * FIXME: Add + * if (tcon->use_resilient) + * SMB2_ioctl(xid, ... FSCTL_LMR_REQUEST_RESILIENCY, true); + */ + if (buf) { /* open response does not have IndexNumber field - get it */ rc = SMB2_get_srv_num(xid, oparms->tcon, fid->persistent_fid, -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
