Commit 0ac4e291 authored by Samuel Cabrero's avatar Samuel Cabrero Committed by Steve French
Browse files

cifs: add witness mount option and data structs 



Add 'witness' mount option to register for witness notifications.

Signed-off-by: default avatarSamuel Cabrero <scabrero@suse.de>
Reviewed-by: default avatarAurelien Aptel <aaptel@suse.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 06f08dab

fs/cifs/cifsfs.c

+5 −0
Original line number Diff line number Diff line
@@ -638,6 +638,11 @@ cifs_show_options(struct seq_file *s, struct dentry *root) 
		seq_printf(s, ",multichannel,max_channels=%zu",

			   tcon->ses->chan_max);



#ifdef CONFIG_CIFS_SWN_UPCALL

	if (tcon->use_witness)

		seq_puts(s, ",witness");

#endif



	return 0;

}

fs/cifs/cifsglob.h

+3 −0
Original line number Diff line number Diff line
@@ -1086,6 +1086,9 @@ struct cifs_tcon { 
	int remap:2;

	struct list_head ulist; /* cache update list */

#endif

#ifdef CONFIG_CIFS_SWN_UPCALL

	bool use_witness:1; /* use witness protocol */

#endif

};



/*

fs/cifs/connect.c

+25 −0
Original line number Diff line number Diff line
@@ -1944,6 +1944,8 @@ cifs_put_tcon(struct cifs_tcon *tcon) 
		return;

	}



	/* TODO witness unregister */



	list_del_init(&tcon->tcon_list);

	spin_unlock(&cifs_tcp_ses_lock);
@@ -2104,6 +2106,26 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx) 
		}

		tcon->use_resilient = true;

	}

#ifdef CONFIG_CIFS_SWN_UPCALL

	tcon->use_witness = false;

	if (ctx->witness) {

		if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {

			if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {

				/* TODO witness register */

				tcon->use_witness = true;

			} else {

				/* TODO: try to extend for non-cluster uses (eg multichannel) */

				cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");

				rc = -EOPNOTSUPP;

				goto out_fail;

			}

		} else {

			cifs_dbg(VFS, "SMB3 or later required for witness option\n");

			rc = -EOPNOTSUPP;

			goto out_fail;

		}

	}

#endif



	/* If the user really knows what they are doing they can override */

	if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
@@ -3856,6 +3878,9 @@ cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid) 
	ctx->sectype = master_tcon->ses->sectype;

	ctx->sign = master_tcon->ses->sign;

	ctx->seal = master_tcon->seal;

#ifdef CONFIG_CIFS_SWN_UPCALL

	ctx->witness = master_tcon->use_witness;

#endif



	rc = cifs_set_vol_auth(ctx, master_tcon->ses);

	if (rc) {

fs/cifs/fs_context.c

+8 −0
Original line number Diff line number Diff line
@@ -119,6 +119,7 @@ const struct fs_parameter_spec smb3_fs_parameters[] = { 
	fsparam_flag("modesid", Opt_modesid),

	fsparam_flag("rootfs", Opt_rootfs),

	fsparam_flag("compress", Opt_compress),

	fsparam_flag("witness", Opt_witness),



	/* Mount options which take numeric value */

	fsparam_u32("backupuid", Opt_backupuid),
@@ -1004,6 +1005,13 @@ static int smb3_fs_context_parse_param(struct fs_context *fc, 
		if (cifs_parse_cache_flavor(param->string, ctx) != 0)

			goto cifs_parse_mount_err;

		break;

	case Opt_witness:

#ifndef CONFIG_CIFS_SWN_UPCALL

		cifs_dbg(VFS, "Witness support needs CONFIG_CIFS_SWN_UPCALL config option\n");

			goto cifs_parse_mount_err;

#endif

		ctx->witness = true;

		break;

	case Opt_rootfs:

#ifdef CONFIG_CIFS_ROOT

		ctx->rootfs = true;

fs/cifs/fs_context.h

+2 −0
Original line number Diff line number Diff line
@@ -102,6 +102,7 @@ enum cifs_param { 
	Opt_rootfs,

	Opt_multichannel,

	Opt_compress,

	Opt_witness,



	/* Mount options which take numeric value */

	Opt_backupuid,
@@ -241,6 +242,7 @@ struct smb3_fs_context { 
	unsigned int max_channels;

	__u16 compression; /* compression algorithm 0xFFFF default 0=disabled */

	bool rootfs:1; /* if it's a SMB root file system */

	bool witness:1; /* use witness protocol */



	char *mount_options;

};