module: fold usermode helper kmod into modules directory

The kernel/kmod.c is already only built if we enabled modules, so
just stuff it under kernel/module/kmod.c and unify the MAINTAINERS
file for it.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

1 files changed, 0 insertions, 177 deletions

diff --git a/kernel/kmod.c b/kernel/kmod.c
deleted file mode 100644
index b717134ebe17..000000000000
--- a/kernel/kmod.c
+++ /dev/null
@@ -1,177 +0,0 @@
-/*
- * kmod - the kernel module loader
- */
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/sched/task.h>
-#include <linux/binfmts.h>
-#include <linux/syscalls.h>
-#include <linux/unistd.h>
-#include <linux/kmod.h>
-#include <linux/slab.h>
-#include <linux/completion.h>
-#include <linux/cred.h>
-#include <linux/file.h>
-#include <linux/fdtable.h>
-#include <linux/workqueue.h>
-#include <linux/security.h>
-#include <linux/mount.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/resource.h>
-#include <linux/notifier.h>
-#include <linux/suspend.h>
-#include <linux/rwsem.h>
-#include <linux/ptrace.h>
-#include <linux/async.h>
-#include <linux/uaccess.h>
-
-#include <trace/events/module.h>
-
-/*
- * Assuming:
- *
- * threads = div64_u64((u64) totalram_pages * (u64) PAGE_SIZE,
- *		       (u64) THREAD_SIZE * 8UL);
- *
- * If you need less than 50 threads would mean we're dealing with systems
- * smaller than 3200 pages. This assumes you are capable of having ~13M memory,
- * and this would only be an upper limit, after which the OOM killer would take
- * effect. Systems like these are very unlikely if modules are enabled.
- */
-#define MAX_KMOD_CONCURRENT 50
-static atomic_t kmod_concurrent_max = ATOMIC_INIT(MAX_KMOD_CONCURRENT);
-static DECLARE_WAIT_QUEUE_HEAD(kmod_wq);
-
-/*
- * This is a restriction on having *all* MAX_KMOD_CONCURRENT threads
- * running at the same time without returning. When this happens we
- * believe you've somehow ended up with a recursive module dependency
- * creating a loop.
- *
- * We have no option but to fail.
- *
- * Userspace should proactively try to detect and prevent these.
- */
-#define MAX_KMOD_ALL_BUSY_TIMEOUT 5
-
-/*
-	modprobe_path is set via /proc/sys.
-*/
-char modprobe_path[KMOD_PATH_LEN] = CONFIG_MODPROBE_PATH;
-
-static void free_modprobe_argv(struct subprocess_info *info)
-{
-	kfree(info->argv[3]); /* check call_modprobe() */
-	kfree(info->argv);
-}
-
-static int call_modprobe(char *module_name, int wait)
-{
-	struct subprocess_info *info;
-	static char *envp[] = {
-		"HOME=/",
-		"TERM=linux",
-		"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
-		NULL
-	};
-
-	char **argv = kmalloc(sizeof(char *[5]), GFP_KERNEL);
-	if (!argv)
-		goto out;
-
-	module_name = kstrdup(module_name, GFP_KERNEL);
-	if (!module_name)
-		goto free_argv;
-
-	argv[0] = modprobe_path;
-	argv[1] = "-q";
-	argv[2] = "--";
-	argv[3] = module_name;	/* check free_modprobe_argv() */
-	argv[4] = NULL;
-
-	info = call_usermodehelper_setup(modprobe_path, argv, envp, GFP_KERNEL,
-					 NULL, free_modprobe_argv, NULL);
-	if (!info)
-		goto free_module_name;
-
-	return call_usermodehelper_exec(info, wait | UMH_KILLABLE);
-
-free_module_name:
-	kfree(module_name);
-free_argv:
-	kfree(argv);
-out:
-	return -ENOMEM;
-}
-
-/**
- * __request_module - try to load a kernel module
- * @wait: wait (or not) for the operation to complete
- * @fmt: printf style format string for the name of the module
- * @...: arguments as specified in the format string
- *
- * Load a module using the user mode module loader. The function returns
- * zero on success or a negative errno code or positive exit code from
- * "modprobe" on failure. Note that a successful module load does not mean
- * the module did not then unload and exit on an error of its own. Callers
- * must check that the service they requested is now available not blindly
- * invoke it.
- *
- * If module auto-loading support is disabled then this function
- * simply returns -ENOENT.
- */
-int __request_module(bool wait, const char *fmt, ...)
-{
-	va_list args;
-	char module_name[MODULE_NAME_LEN];
-	int ret;
-
-	/*
-	 * We don't allow synchronous module loading from async.  Module
-	 * init may invoke async_synchronize_full() which will end up
-	 * waiting for this task which already is waiting for the module
-	 * loading to complete, leading to a deadlock.
-	 */
-	WARN_ON_ONCE(wait && current_is_async());
-
-	if (!modprobe_path[0])
-		return -ENOENT;
-
-	va_start(args, fmt);
-	ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
-	va_end(args);
-	if (ret >= MODULE_NAME_LEN)
-		return -ENAMETOOLONG;
-
-	ret = security_kernel_module_request(module_name);
-	if (ret)
-		return ret;
-
-	if (atomic_dec_if_positive(&kmod_concurrent_max) < 0) {
-		pr_warn_ratelimited("request_module: kmod_concurrent_max (%u) close to 0 (max_modprobes: %u), for module %s, throttling...",
-				    atomic_read(&kmod_concurrent_max),
-				    MAX_KMOD_CONCURRENT, module_name);
-		ret = wait_event_killable_timeout(kmod_wq,
-						  atomic_dec_if_positive(&kmod_concurrent_max) >= 0,
-						  MAX_KMOD_ALL_BUSY_TIMEOUT * HZ);
-		if (!ret) {
-			pr_warn_ratelimited("request_module: modprobe %s cannot be processed, kmod busy with %d threads for more than %d seconds now",
-					    module_name, MAX_KMOD_CONCURRENT, MAX_KMOD_ALL_BUSY_TIMEOUT);
-			return -ETIME;
-		} else if (ret == -ERESTARTSYS) {
-			pr_warn_ratelimited("request_module: sigkill sent for modprobe %s, giving up", module_name);
-			return ret;
-		}
-	}
-
-	trace_module_request(module_name, wait, _RET_IP_);
-
-	ret = call_modprobe(module_name, wait ? UMH_WAIT_PROC : UMH_WAIT_EXEC);
-
-	atomic_inc(&kmod_concurrent_max);
-	wake_up(&kmod_wq);
-
-	return ret;
-}
-EXPORT_SYMBOL(__request_module);