[PATCH 02/10] Driver core: let request_module() send a /sys/modules/kmod/-uevent
From: Kay Sievers <[EMAIL PROTECTED]>
On recent systems, calls to /sbin/modprobe are handled by udev depending
on the kind of device the kernel has discovered. This patch creates an
uevent for the kernels internal request_module(), to let udev take control
over the request, instead of forking the binary directly by the kernel.
The direct execution of /sbin/modprobe can be disabled by setting:
/sys/module/kmod/mod_request_helper (/proc/sys/kernel/modprobe)
to an empty string, the same way /proc/sys/kernel/hotplug is disabled on an
udev system.
Signed-off-by: Kay Sievers <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>
---
include/linux/kmod.h |2 +
kernel/kmod.c| 120 ++
kernel/module.c | 26 +++
kernel/params.c |1 +
4 files changed, 139 insertions(+), 10 deletions(-)
diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index 10f505c..cc8e674 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -28,8 +28,10 @@
#ifdef CONFIG_KMOD
/* modprobe exit status on success, -ve on error. Return value
* usually useless though. */
+extern void kmod_sysfs_init(void);
extern int request_module(const char * name, ...) __attribute__ ((format
(printf, 1, 2)));
#else
+static inline void kmod_sysfs_init(void) {};
static inline int request_module(const char * name, ...) { return -ENOSYS; }
#endif
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 7962761..9f923f8 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -36,6 +36,8 @@
#include
#include
+extern int delete_module(const char *name, unsigned int flags);
+
extern int max_threads;
static struct workqueue_struct *khelper_wq;
@@ -46,6 +48,7 @@ static struct workqueue_struct *khelper_wq;
modprobe_path is set via /proc/sys.
*/
char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe";
+struct module_kobject kmod_mk;
/**
* request_module - try to load a kernel module
@@ -75,6 +78,11 @@ int request_module(const char *fmt, ...)
static atomic_t kmod_concurrent = ATOMIC_INIT(0);
#define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
static int kmod_loop_msg;
+ char modalias[16 + MODULE_NAME_LEN] = "MODALIAS=";
+ char *uevent_envp[2] = {
+ modalias,
+ NULL
+ };
va_start(args, fmt);
ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
@@ -82,6 +90,12 @@ int request_module(const char *fmt, ...)
if (ret >= MODULE_NAME_LEN)
return -ENAMETOOLONG;
+ strcpy([strlen("MODALIAS=")], module_name);
+ kobject_uevent_env(_mk.kobj, KOBJ_CHANGE, uevent_envp);
+
+ if (modprobe_path[0] == '\0')
+ goto out;
+
/* If modprobe needs a service that is in a module, we get a recursive
* loop. Limit the number of running kmod threads to max_threads/2 or
* MAX_KMOD_CONCURRENT, whichever is the smaller. A cleaner method
@@ -108,9 +122,115 @@ int request_module(const char *fmt, ...)
ret = call_usermodehelper(modprobe_path, argv, envp, 1);
atomic_dec(_concurrent);
+out:
return ret;
}
EXPORT_SYMBOL(request_module);
+
+static ssize_t store_mod_request(struct module_attribute *mattr,
+struct module *mod,
+ const char *buffer, size_t count)
+{
+ char name[MODULE_NAME_LEN];
+ int ret;
+
+ if (count < 1 || count+1 > MODULE_NAME_LEN)
+ return -EINVAL;
+ memcpy(name, buffer, count);
+ name[count] = '\0';
+ if (name[count-1] == '\n')
+ name[count-1] = '\0';
+
+ ret = request_module(name);
+ if (ret < 0)
+ return ret;
+ return count;
+}
+
+static struct module_attribute mod_request = {
+ .attr = { .name = "mod_request", .mode = S_IWUSR, .owner = THIS_MODULE
},
+ .store = store_mod_request,
+};
+
+#ifdef CONFIG_MODULE_UNLOAD
+static ssize_t store_mod_unload(struct module_attribute *mattr,
+ struct module *mod,
+ const char *buffer, size_t count)
+{
+ char name[MODULE_NAME_LEN];
+ int ret;
+
+ if (count < 1 || count+1 > MODULE_NAME_LEN)
+ return -EINVAL;
+ memcpy(name, buffer, count);
+ name[count] = '\0';
+ if (name[count-1] == '\n')
+ name[count-1] = '\0';
+
+ ret = delete_module(name, O_NONBLOCK);
+ if (ret < 0)
+ return ret;
+ return count;
+}
+
+static struct module_attribute mod_unload = {
+ .attr = { .name = "mod_unload", .mode = S_IWUSR, .owner = THIS_MODULE },
+ .store = store_mod_unload,
+};
+#endif
+
+static ssize_t show_mod_request_helper(struct module_attribute *mattr,
+ struct module *mod,
+ char *buffer)
+{
+ return sprintf(buffer,
[PATCH 02/10] Driver core: let request_module() send a /sys/modules/kmod/-uevent
From: Kay Sievers [EMAIL PROTECTED]
On recent systems, calls to /sbin/modprobe are handled by udev depending
on the kind of device the kernel has discovered. This patch creates an
uevent for the kernels internal request_module(), to let udev take control
over the request, instead of forking the binary directly by the kernel.
The direct execution of /sbin/modprobe can be disabled by setting:
/sys/module/kmod/mod_request_helper (/proc/sys/kernel/modprobe)
to an empty string, the same way /proc/sys/kernel/hotplug is disabled on an
udev system.
Signed-off-by: Kay Sievers [EMAIL PROTECTED]
Signed-off-by: Greg Kroah-Hartman [EMAIL PROTECTED]
---
include/linux/kmod.h |2 +
kernel/kmod.c| 120 ++
kernel/module.c | 26 +++
kernel/params.c |1 +
4 files changed, 139 insertions(+), 10 deletions(-)
diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index 10f505c..cc8e674 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -28,8 +28,10 @@
#ifdef CONFIG_KMOD
/* modprobe exit status on success, -ve on error. Return value
* usually useless though. */
+extern void kmod_sysfs_init(void);
extern int request_module(const char * name, ...) __attribute__ ((format
(printf, 1, 2)));
#else
+static inline void kmod_sysfs_init(void) {};
static inline int request_module(const char * name, ...) { return -ENOSYS; }
#endif
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 7962761..9f923f8 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -36,6 +36,8 @@
#include linux/resource.h
#include asm/uaccess.h
+extern int delete_module(const char *name, unsigned int flags);
+
extern int max_threads;
static struct workqueue_struct *khelper_wq;
@@ -46,6 +48,7 @@ static struct workqueue_struct *khelper_wq;
modprobe_path is set via /proc/sys.
*/
char modprobe_path[KMOD_PATH_LEN] = /sbin/modprobe;
+struct module_kobject kmod_mk;
/**
* request_module - try to load a kernel module
@@ -75,6 +78,11 @@ int request_module(const char *fmt, ...)
static atomic_t kmod_concurrent = ATOMIC_INIT(0);
#define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
static int kmod_loop_msg;
+ char modalias[16 + MODULE_NAME_LEN] = MODALIAS=;
+ char *uevent_envp[2] = {
+ modalias,
+ NULL
+ };
va_start(args, fmt);
ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
@@ -82,6 +90,12 @@ int request_module(const char *fmt, ...)
if (ret = MODULE_NAME_LEN)
return -ENAMETOOLONG;
+ strcpy(modalias[strlen(MODALIAS=)], module_name);
+ kobject_uevent_env(kmod_mk.kobj, KOBJ_CHANGE, uevent_envp);
+
+ if (modprobe_path[0] == '\0')
+ goto out;
+
/* If modprobe needs a service that is in a module, we get a recursive
* loop. Limit the number of running kmod threads to max_threads/2 or
* MAX_KMOD_CONCURRENT, whichever is the smaller. A cleaner method
@@ -108,9 +122,115 @@ int request_module(const char *fmt, ...)
ret = call_usermodehelper(modprobe_path, argv, envp, 1);
atomic_dec(kmod_concurrent);
+out:
return ret;
}
EXPORT_SYMBOL(request_module);
+
+static ssize_t store_mod_request(struct module_attribute *mattr,
+struct module *mod,
+ const char *buffer, size_t count)
+{
+ char name[MODULE_NAME_LEN];
+ int ret;
+
+ if (count 1 || count+1 MODULE_NAME_LEN)
+ return -EINVAL;
+ memcpy(name, buffer, count);
+ name[count] = '\0';
+ if (name[count-1] == '\n')
+ name[count-1] = '\0';
+
+ ret = request_module(name);
+ if (ret 0)
+ return ret;
+ return count;
+}
+
+static struct module_attribute mod_request = {
+ .attr = { .name = mod_request, .mode = S_IWUSR, .owner = THIS_MODULE
},
+ .store = store_mod_request,
+};
+
+#ifdef CONFIG_MODULE_UNLOAD
+static ssize_t store_mod_unload(struct module_attribute *mattr,
+ struct module *mod,
+ const char *buffer, size_t count)
+{
+ char name[MODULE_NAME_LEN];
+ int ret;
+
+ if (count 1 || count+1 MODULE_NAME_LEN)
+ return -EINVAL;
+ memcpy(name, buffer, count);
+ name[count] = '\0';
+ if (name[count-1] == '\n')
+ name[count-1] = '\0';
+
+ ret = delete_module(name, O_NONBLOCK);
+ if (ret 0)
+ return ret;
+ return count;
+}
+
+static struct module_attribute mod_unload = {
+ .attr = { .name = mod_unload, .mode = S_IWUSR, .owner = THIS_MODULE },
+ .store = store_mod_unload,
+};
+#endif
+
+static ssize_t show_mod_request_helper(struct module_attribute *mattr,
+ struct module *mod,
+ char *buffer)
+{
+ return
