6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paulo Alcantara <pc@xxxxxxxxxxxxx> [ Upstream commit eb90e8ecb2b54ac1af51e28596e0ef7ba351476d ] 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: Paulo Alcantara <pc@xxxxxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/smb/client/cifsglob.h | 6 ++++++ fs/smb/client/connect.c | 2 ++ fs/smb/client/fs_context.c | 35 +++++++++++++++++++++++++++++++++++ fs/smb/client/fs_context.h | 9 +++++++++ 4 files changed, 52 insertions(+) diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h index fdadda4024f46..08540541046c1 100644 --- a/fs/smb/client/cifsglob.h +++ b/fs/smb/client/cifsglob.h @@ -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; diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index e28f011f11d6c..deba1cfd11801 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -2805,6 +2805,8 @@ 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; } diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c index f119035a82725..535885fbdf51d 100644 --- a/fs/smb/client/fs_context.c +++ b/fs/smb/client/fs_context.c @@ -175,6 +175,7 @@ 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), @@ -297,6 +298,35 @@ 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) { \ @@ -1595,6 +1625,10 @@ 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 ... */ @@ -1683,6 +1717,7 @@ 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; diff --git a/fs/smb/client/fs_context.h b/fs/smb/client/fs_context.h index 369a3fea1dfe0..e77ee81846b31 100644 --- a/fs/smb/client/fs_context.h +++ b/fs/smb/client/fs_context.h @@ -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, @@ -149,6 +156,7 @@ enum cifs_param { Opt_vers, Opt_sec, Opt_cache, + Opt_reparse, /* Mount options to be ignored */ Opt_ignore, @@ -275,6 +283,7 @@ 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[]; -- 2.43.0