[patch 7/7] tidy up usermode helper waiting a bit
From: Jeremy Fitzhardinge
Date: Fri May 11 2007 - 15:13:06 EST
Rather than using a tri-state integer for the wait flag in
call_usermodehelper_exec, define a proper enum, and use that. I've
preserved the integer values so that any callers I've missed should
still work OK.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Randy Dunlap <randy.dunlap@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Bjorn Helgaas <bjorn.helgaas@xxxxxx>
Cc: Joel Becker <joel.becker@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Kay Sievers <kay.sievers@xxxxxxxx>
Cc: Srivatsa Vaddagiri <vatsa@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
---
arch/i386/mach-voyager/voyager_thread.c | 2 +-
arch/x86_64/kernel/mce.c | 2 +-
drivers/macintosh/therm_pm72.c | 3 ++-
drivers/macintosh/windfarm_core.c | 3 ++-
drivers/net/hamradio/baycom_epp.c | 2 +-
drivers/pnp/pnpbios/core.c | 2 +-
fs/ocfs2/heartbeat.c | 2 +-
include/linux/kmod.h | 12 +++++++++---
kernel/cpuset.c | 2 +-
kernel/kmod.c | 29 +++++++++++++++++------------
kernel/sys.c | 2 +-
lib/kobject_uevent.c | 2 +-
net/bridge/br_stp_if.c | 2 +-
security/keys/request_key.c | 3 ++-
14 files changed, 41 insertions(+), 27 deletions(-)
===================================================================
--- a/arch/i386/mach-voyager/voyager_thread.c
+++ b/arch/i386/mach-voyager/voyager_thread.c
@@ -52,7 +52,7 @@ execute(const char *string)
NULL,
};
- if ((ret = call_usermodehelper(argv[0], argv, envp, 1)) != 0) {
+ if ((ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC)) != 0) {
printk(KERN_ERR "Voyager failed to run \"%s\": %i\n",
string, ret);
}
===================================================================
--- a/arch/x86_64/kernel/mce.c
+++ b/arch/x86_64/kernel/mce.c
@@ -174,7 +174,7 @@ static void do_mce_trigger(void)
if (events != atomic_read(&mce_logged) && trigger[0]) {
/* Small race window, but should be harmless. */
atomic_set(&mce_logged, events);
- call_usermodehelper(trigger, trigger_argv, NULL, -1);
+ call_usermodehelper(trigger, trigger_argv, NULL, UMH_NO_WAIT);
}
}
===================================================================
--- a/drivers/macintosh/therm_pm72.c
+++ b/drivers/macintosh/therm_pm72.c
@@ -1770,7 +1770,8 @@ static int call_critical_overtemp(void)
"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
NULL };
- return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
+ return call_usermodehelper(critical_overtemp_path,
+ argv, envp, UMH_WAIT_EXEC);
}
===================================================================
--- a/drivers/macintosh/windfarm_core.c
+++ b/drivers/macintosh/windfarm_core.c
@@ -80,7 +80,8 @@ int wf_critical_overtemp(void)
"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
NULL };
- return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
+ return call_usermodehelper(critical_overtemp_path,
+ argv, envp, UMH_WAIT_EXEC);
}
EXPORT_SYMBOL_GPL(wf_critical_overtemp);
===================================================================
--- a/drivers/net/hamradio/baycom_epp.c
+++ b/drivers/net/hamradio/baycom_epp.c
@@ -320,7 +320,7 @@ static int eppconfig(struct baycom_state
sprintf(portarg, "%ld", bc->pdev->port->base);
printk(KERN_DEBUG "%s: %s -s -p %s -m %s\n", bc_drvname, eppconfig_path, portarg, modearg);
- return call_usermodehelper(eppconfig_path, argv, envp, 1);
+ return call_usermodehelper(eppconfig_path, argv, envp, UMH_WAIT_PROC);
}
/* ---------------------------------------------------------------------- */
===================================================================
--- a/drivers/pnp/pnpbios/core.c
+++ b/drivers/pnp/pnpbios/core.c
@@ -147,7 +147,7 @@ static int pnp_dock_event(int dock, stru
info->location_id, info->serial, info->capabilities);
envp[i] = NULL;
- value = call_usermodehelper (argv [0], argv, envp, 0);
+ value = call_usermodehelper (argv [0], argv, envp, UMH_WAIT_EXEC);
kfree (buf);
kfree (envp);
return 0;
===================================================================
--- a/fs/ocfs2/heartbeat.c
+++ b/fs/ocfs2/heartbeat.c
@@ -209,7 +209,7 @@ void ocfs2_stop_heartbeat(struct ocfs2_s
envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
envp[2] = NULL;
- ret = call_usermodehelper(argv[0], argv, envp, 1);
+ ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
if (ret < 0)
mlog_errno(ret);
}
===================================================================
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -51,15 +51,21 @@ void call_usermodehelper_setcleanup(stru
void call_usermodehelper_setcleanup(struct subprocess_info *info,
void (*cleanup)(char **argv, char **envp));
+enum umh_wait {
+ UMH_NO_WAIT = -1, /* don't wait at all */
+ UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
+ UMH_WAIT_PROC = 1, /* wait for the process to complete */
+};
+
/* Actually execute the sub-process */
-int call_usermodehelper_exec(struct subprocess_info *info, int wait);
+int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
/* Free the subprocess_info. This is only needed if you're not going
to call call_usermodehelper_exec */
void call_usermodehelper_freeinfo(struct subprocess_info *info);
static inline int
-call_usermodehelper(char *path, char **argv, char **envp, int wait)
+call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
{
struct subprocess_info *info;
@@ -71,7 +77,7 @@ call_usermodehelper(char *path, char **a
static inline int
call_usermodehelper_keys(char *path, char **argv, char **envp,
- struct key *session_keyring, int wait)
+ struct key *session_keyring, enum umh_wait wait)
{
struct subprocess_info *info;
===================================================================
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -516,7 +516,7 @@ static void cpuset_release_agent(const c
envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
envp[i] = NULL;
- call_usermodehelper(argv[0], argv, envp, 0);
+ call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
kfree(pathbuf);
}
===================================================================
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -119,7 +119,7 @@ struct subprocess_info {
char **argv;
char **envp;
struct key *ring;
- int wait;
+ enum umh_wait wait;
int retval;
struct file *stdin;
void (*cleanup)(char **argv, char **envp);
@@ -225,7 +225,7 @@ static int wait_for_helper(void *data)
sub_info->retval = ret;
}
- if (sub_info->wait < 0)
+ if (sub_info->wait == UMH_NO_WAIT)
call_usermodehelper_freeinfo(sub_info);
else
complete(sub_info->complete);
@@ -238,26 +238,31 @@ static void __call_usermodehelper(struct
struct subprocess_info *sub_info =
container_of(work, struct subprocess_info, work);
pid_t pid;
- int wait = sub_info->wait;
+ enum umh_wait wait = sub_info->wait;
/* CLONE_VFORK: wait until the usermode helper has execve'd
* successfully We need the data structures to stay around
* until that is done. */
- if (wait)
+ if (wait == UMH_WAIT_PROC)
pid = kernel_thread(wait_for_helper, sub_info,
CLONE_FS | CLONE_FILES | SIGCHLD);
else
pid = kernel_thread(____call_usermodehelper, sub_info,
CLONE_VFORK | SIGCHLD);
- if (wait < 0)
- return;
-
- if (pid < 0) {
+ switch(wait) {
+ case UMH_NO_WAIT:
+ break;
+
+ case UMH_WAIT_PROC:
+ if (pid > 0)
+ break;
sub_info->retval = pid;
+ /* FALLTHROUGH */
+
+ case UMH_WAIT_EXEC:
complete(sub_info->complete);
- } else if (!wait)
- complete(sub_info->complete);
+ }
}
/**
@@ -359,7 +364,7 @@ EXPORT_SYMBOL(call_usermodehelper_stdinp
* (ie. it runs with full root capabilities).
*/
int call_usermodehelper_exec(struct subprocess_info *sub_info,
- int wait)
+ enum umh_wait wait)
{
DECLARE_COMPLETION_ONSTACK(done);
int retval;
@@ -378,7 +383,7 @@ int call_usermodehelper_exec(struct subp
sub_info->wait = wait;
queue_work(khelper_wq, &sub_info->work);
- if (wait < 0) /* task has freed sub_info */
+ if (wait == UMH_NO_WAIT) /* task has freed sub_info */
return 0;
wait_for_completion(&done);
retval = sub_info->retval;
===================================================================
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2310,7 +2310,7 @@ int orderly_poweroff(bool force)
call_usermodehelper_setcleanup(info, argv_cleanup);
- ret = call_usermodehelper_exec(info, -1);
+ ret = call_usermodehelper_exec(info, UMH_NO_WAIT);
out:
if (ret && force) {
===================================================================
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -208,7 +208,7 @@ int kobject_uevent_env(struct kobject *k
argv [0] = uevent_helper;
argv [1] = (char *)subsystem;
argv [2] = NULL;
- call_usermodehelper (argv[0], argv, envp, 0);
+ call_usermodehelper (argv[0], argv, envp, UMH_WAIT_EXEC);
}
exit:
===================================================================
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -125,7 +125,7 @@ static void br_stp_start(struct net_brid
char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
char *envp[] = { NULL };
- r = call_usermodehelper(BR_STP_PROG, argv, envp, 1);
+ r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
if (r == 0) {
br->stp_enabled = BR_USER_STP;
printk(KERN_INFO "%s: userspace STP started\n", br->dev->name);
===================================================================
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -108,7 +108,8 @@ static int call_sbin_request_key(struct
argv[i] = NULL;
/* do it */
- ret = call_usermodehelper_keys(argv[0], argv, envp, keyring, 1);
+ ret = call_usermodehelper_keys(argv[0], argv, envp, keyring,
+ UMH_WAIT_PROC);
error_link:
key_put(keyring);
--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/