Commit eb90e8ec authored by Paulo Alcantara's avatar Paulo Alcantara Committed by Steve French
Browse files

smb: client: introduce reparse mount option 



Allow the user to create special files and symlinks by choosing
between WSL and NFS reparse points via 'reparse={nfs,wsl}' mount
options.  If unset or 'reparse=default', the client will default to
creating them via NFS reparse points.

Creating WSL reparse points isn't supported yet, so simply return
error when attempting to mount with 'reparse=wsl' for now.

Signed-off-by: default avatarPaulo Alcantara <pc@manguebit.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 71f15c90

fs/smb/client/cifsglob.h

+6 −0
Original line number Diff line number Diff line
@@ -153,6 +153,12 @@ enum securityEnum { 
	Kerberos,		/* Kerberos via SPNEGO */

};



enum cifs_reparse_type {

	CIFS_REPARSE_TYPE_NFS,

	CIFS_REPARSE_TYPE_WSL,

	CIFS_REPARSE_TYPE_DEFAULT = CIFS_REPARSE_TYPE_NFS,

};



struct session_key {

	unsigned int len;

	char *response;

fs/smb/client/connect.c

+2 −0
Original line number Diff line number Diff line
@@ -2803,6 +2803,8 @@ compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data) 
		return 0;

	if (old->ctx->closetimeo != new->ctx->closetimeo)

		return 0;

	if (old->ctx->reparse_type != new->ctx->reparse_type)

		return 0;



	return 1;

}

fs/smb/client/fs_context.c

+35 −0
Original line number Diff line number Diff line
@@ -174,6 +174,7 @@ const struct fs_parameter_spec smb3_fs_parameters[] = { 
	fsparam_string("vers", Opt_vers),

	fsparam_string("sec", Opt_sec),

	fsparam_string("cache", Opt_cache),

	fsparam_string("reparse", Opt_reparse),



	/* Arguments that should be ignored */

	fsparam_flag("guest", Opt_ignore),
@@ -296,6 +297,35 @@ cifs_parse_cache_flavor(struct fs_context *fc, char *value, struct smb3_fs_conte 
	return 0;

}



static const match_table_t reparse_flavor_tokens = {

	{ Opt_reparse_default,	"default" },

	{ Opt_reparse_nfs,	"nfs" },

	{ Opt_reparse_wsl,	"wsl" },

	{ Opt_reparse_err,	NULL },

};



static int parse_reparse_flavor(struct fs_context *fc, char *value,

				struct smb3_fs_context *ctx)

{

	substring_t args[MAX_OPT_ARGS];



	switch (match_token(value, reparse_flavor_tokens, args)) {

	case Opt_reparse_default:

		ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;

		break;

	case Opt_reparse_nfs:

		ctx->reparse_type = CIFS_REPARSE_TYPE_NFS;

		break;

	case Opt_reparse_wsl:

		cifs_errorf(fc, "unsupported reparse= option: %s\n", value);

		return 1;

	default:

		cifs_errorf(fc, "bad reparse= option: %s\n", value);

		return 1;

	}

	return 0;

}



#define DUP_CTX_STR(field)						\

do {									\

	if (ctx->field) {						\
@@ -1566,6 +1596,10 @@ static int smb3_fs_context_parse_param(struct fs_context *fc, 
	case Opt_rdma:

		ctx->rdma = true;

		break;

	case Opt_reparse:

		if (parse_reparse_flavor(fc, param->string, ctx))

			goto cifs_parse_mount_err;

		break;

	}

	/* case Opt_ignore: - is ignored as expected ... */
@@ -1652,6 +1686,7 @@ int smb3_init_fs_context(struct fs_context *fc) 
	ctx->backupgid_specified = false; /* no backup intent for a group */



	ctx->retrans = 1;

	ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;



/*

 *	short int override_uid = -1;

fs/smb/client/fs_context.h

+9 −0
Original line number Diff line number Diff line
@@ -41,6 +41,13 @@ enum { 
	Opt_cache_err

};



enum cifs_reparse_parm {

	Opt_reparse_default,

	Opt_reparse_nfs,

	Opt_reparse_wsl,

	Opt_reparse_err

};



enum cifs_sec_param {

	Opt_sec_krb5,

	Opt_sec_krb5i,
@@ -148,6 +155,7 @@ enum cifs_param { 
	Opt_vers,

	Opt_sec,

	Opt_cache,

	Opt_reparse,



	/* Mount options to be ignored */

	Opt_ignore,
@@ -271,6 +279,7 @@ struct smb3_fs_context { 
	char *leaf_fullpath;

	struct cifs_ses *dfs_root_ses;

	bool dfs_automount:1; /* set for dfs automount only */

	enum cifs_reparse_type reparse_type;

};



extern const struct fs_parameter_spec smb3_fs_parameters[];