autofs-5.0.7 - add symlink pseudo option
From: Ian Kent <raven@themaw.net>
Add a "symlink" pseudo option to tell the bind mount module to symlink
instead of bind when mounting mounts other than direct mounts and
non-root indirect mount offset mounts (aka. non-root multi-mount
entries).
---
CHANGELOG | 1 +
include/automount.h | 3 +++
lib/master_parse.y | 8 +++++++-
lib/master_tok.l | 1 +
man/auto.master.5.in | 8 ++++++++
modules/mount_autofs.c | 5 +++++
modules/mount_bind.c | 36 +++++++++++++++++++++++++++++++++++-
7 files changed, 60 insertions(+), 2 deletions(-)
diff --git a/CHANGELOG b/CHANGELOG
index c189483..247d334 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -32,6 +32,7 @@
- fix wildcard multi map regression.
- fix file descriptor leak when reloading the daemon.
- depricate nosymlink pseudo option.
+- add symlink pseudo option.
25/07/2012 autofs-5.0.7
=======================
diff --git a/include/automount.h b/include/automount.h
index 37541f5..e72fa0d 100644
--- a/include/automount.h
+++ b/include/automount.h
@@ -455,6 +455,9 @@ struct kernel_mod_version {
/* Don't use bind mounts even when system supports them */
#define MOUNT_FLAG_NOBIND 0x0020
+/* Use symlinks instead of bind mounting local mounts */
+#define MOUNT_FLAG_SYMLINK 0x0040
+
struct autofs_point {
pthread_t thid;
char *path; /* Mount point name */
diff --git a/lib/master_parse.y b/lib/master_parse.y
index f925b5a..11caf5b 100644
--- a/lib/master_parse.y
+++ b/lib/master_parse.y
@@ -57,6 +57,7 @@ static char *type;
static char *format;
static long timeout;
static long negative_timeout;
+static unsigned symlnk;
static unsigned nobind;
static unsigned ghost;
extern unsigned global_selection_options;
@@ -100,7 +101,7 @@ static int master_fprintf(FILE *, char *, ...);
%token COMMENT
%token MAP
%token OPT_TIMEOUT OPT_NTIMEOUT OPT_NOBIND OPT_NOGHOST OPT_GHOST OPT_VERBOSE
-%token OPT_DEBUG OPT_RANDOM OPT_USE_WEIGHT
+%token OPT_DEBUG OPT_RANDOM OPT_USE_WEIGHT OPT_SYMLINK
%token COLON COMMA NL DDASH
%type <strtype> map
%type <strtype> options
@@ -186,6 +187,7 @@ line:
| PATH OPT_USE_WEIGHT { master_notify($1); YYABORT; }
| PATH OPT_DEBUG { master_notify($1); YYABORT; }
| PATH OPT_TIMEOUT { master_notify($1); YYABORT; }
+ | PATH OPT_SYMLINK { master_notify($1); YYABORT; }
| PATH OPT_NOBIND { master_notify($1); YYABORT; }
| PATH OPT_GHOST { master_notify($1); YYABORT; }
| PATH OPT_NOGHOST { master_notify($1); YYABORT; }
@@ -557,6 +559,7 @@ option: daemon_option
daemon_option: OPT_TIMEOUT NUMBER { timeout = $2; }
| OPT_NTIMEOUT NUMBER { negative_timeout = $2; }
+ | OPT_SYMLINK { symlnk = 1; }
| OPT_NOBIND { nobind = 1; }
| OPT_NOGHOST { ghost = 0; }
| OPT_GHOST { ghost = 1; }
@@ -627,6 +630,7 @@ static void local_init_vars(void)
debug = 0;
timeout = -1;
negative_timeout = 0;
+ symlnk = 0;
nobind = 0;
ghost = defaults_get_browse_mode();
random_selection = global_selection_options & MOUNT_FLAG_RANDOM_SELECT;
@@ -811,6 +815,8 @@ int master_parse_entry(const char *buffer, unsigned int default_timeout, unsigne
entry->ap->flags |= MOUNT_FLAG_RANDOM_SELECT;
if (use_weight)
entry->ap->flags |= MOUNT_FLAG_USE_WEIGHT_ONLY;
+ if (symlnk)
+ entry->ap->flags |= MOUNT_FLAG_SYMLINK;
if (negative_timeout)
entry->ap->negative_timeout = negative_timeout;
diff --git a/lib/master_tok.l b/lib/master_tok.l
index 30abb15..f9b4e55 100644
--- a/lib/master_tok.l
+++ b/lib/master_tok.l
@@ -361,6 +361,7 @@ OPTNTOUT (-n{OPTWS}|-n{OPTWS}={OPTWS}|--negative-timeout{OPTWS}|--negative-timeo
return(NUMBER);
}
+ -?symlink { return(OPT_SYMLINK); }
-?nobind { return(OPT_NOBIND); }
-?nobrowse { return(OPT_NOGHOST); }
-g|--ghost|-?browse { return(OPT_GHOST); }
diff --git a/man/auto.master.5.in b/man/auto.master.5.in
index 8007542..bbea43a 100644
--- a/man/auto.master.5.in
+++ b/man/auto.master.5.in
@@ -159,6 +159,14 @@ on individual map entries of both types. Bind mounting of NFS file
systems can also be prevented for specific map entrys by adding the
"port=" mount option to the entries.
.TP
+.I "symlink"
+This option makes bind mounting use a symlink instead of an actual bind
+mount. It is an autofs specific option that is a pseudo mount option and
+so is given without a leading dash. It may be used with indirect map
+entries only, either in the master map (so it effects all map entries)
+or with individual map entries. The option is ignored for direct mounts
+and non-root offest mount entries.
+.TP
.I "\-r, \-\-random-multimount-selection"
Enables the use of ramdom selection when choosing a host from a
list of replicated servers. This option is applied to this mount
diff --git a/modules/mount_autofs.c b/modules/mount_autofs.c
index ef16020..8c1e600 100644
--- a/modules/mount_autofs.c
+++ b/modules/mount_autofs.c
@@ -51,6 +51,7 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name,
int argc, status;
int nobind = ap->flags & MOUNT_FLAG_NOBIND;
int ghost = ap->flags & MOUNT_FLAG_GHOST;
+ int symlnk = ap->flags & MOUNT_FLAG_SYMLINK;
time_t timeout = ap->entry->maps->exp_timeout;
unsigned logopt = ap->logopt;
struct map_type_info *info;
@@ -120,6 +121,8 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name,
nobind = 1;
else if (strncmp(cp, "browse", 6) == 0)
ghost = 1;
+ else if (strncmp(cp, "symlink", 7) == 0)
+ symlnk = 1;
else if (strncmp(cp, "timeout=", 8) == 0) {
char *val = strchr(cp, '=');
unsigned tout;
@@ -158,6 +161,8 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name,
}
nap = entry->ap;
nap->parent = ap;
+ if (symlnk)
+ nap->flags |= MOUNT_FLAG_SYMLINK;
argc = 1;
diff --git a/modules/mount_bind.c b/modules/mount_bind.c
index 9bce686..4975294 100644
--- a/modules/mount_bind.c
+++ b/modules/mount_bind.c
@@ -73,10 +73,44 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name, int
char buf[MAX_ERR_BUF];
int err;
int i, len;
+ int symlnk = (*name != '/' && (ap->flags & MOUNT_FLAG_SYMLINK));
if (ap->flags & MOUNT_FLAG_REMOUNT)
return 0;
+ /* Extract "symlink" pseudo-option which forces local filesystems
+ * to be symlinked instead of bound.
+ */
+ if (*name != '/' && !symlnk && options) {
+ const char *comma;
+ int o_len = strlen(options) + 1;
+
+ for (comma = options; *comma != '\0';) {
+ const char *cp;
+ const char *end;
+
+ while (*comma == ',')
+ comma++;
+
+ /* Skip leading white space */
+ while (*comma == ' ' || *comma == '\t')
+ comma++;
+
+ cp = comma;
+ while (*comma != '\0' && *comma != ',')
+ comma++;
+
+ /* Skip trailing white space */
+ end = comma - 1;
+ while (*comma == ' ' || *comma == '\t')
+ end--;
+
+ o_len = end - cp + 1;
+ if (strncmp("symlink", cp, o_len) == 0)
+ symlnk = 1;
+ }
+ }
+
/* Root offset of multi-mount */
len = strlen(root);
if (root[len - 1] == '/') {
@@ -100,7 +134,7 @@ int mount_mount(struct autofs_point *ap, const char *root, const char *name, int
if (options == NULL || *options == '\0')
options = "defaults";
- if (bind_works) {
+ if (!symlnk && bind_works) {
int status, existed = 1;
debug(ap->logopt, MODPREFIX "calling mkdir_path %s", fullpath);