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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 18:30:06 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
Summary of modules changes for the 5.11 merge window: - Fix a race condition between systemd/udev and the module loader. The module loader was sending a uevent before the module was fully initialized (i.e., before its init function has been called). This means udev can start processing the module uevent before the module has finished initializing, and some udev rules expect that the module has initialized already upon receiving the uevent. This resulted in some systemd mount units failing if udev processes the event faster than the module can finish init. This is fixed by delaying the uevent until after the module has called its init routine. - Make the linker array sections for kernel params and module version attributes more robust by switching to use the alignment of the type in question. Namely, linker section arrays will be constructed using the alignment required by the struct (using __alignof__()) as opposed to a specific value such as sizeof(void *) or sizeof(long). This is less likely to cause breakages should the size of the type ever change (from Johan Hovold) - Fix module state inconsistency by setting it back to GOING when a module fails to load and is on its way out (from Miroslav Benes) - Some comment and code cleanups (from Sergey Shtylyov) Signed-off-by: Jessica Yu <jeyu@kernel.org> -----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEVrp26glSWYuDNrCUwEV+OM47wXIFAl/bVuwQHGpleXVAa2Vy bmVsLm9yZwAKCRDARX44zjvBcgkTEACNqNApglXgtWMphj2kHxKDPboUtMwlRAuN XAokanrQTk3eI9PvQR7lWBceViwUMI5qgfB7l1n9FKUTeo2heijs7YYWlo5y3Oed 9eYBMC2V8M8j7j8V2bXoHBKZHOyMGjZHpwkZDxvU1MlnJUjyz8q6RTRaSk4nutyb fkVMP9tOt699382gJqoVoN0nnXAYCn0CXHJgu2gz7SGegW9+5xAgP2s/NDxJN9Pa lDKeTE78iiV2k4cGfN3y9BhTfEl+LZoO9rXRHZRNkJ1T/mcyG17hrqSzUTxk/7Md iQ9jgNWtt0RYiVUkze54DOZM4T/OT3QrvYEEFbCPj9z5QDDLPRO4pO2+VSi5pBpn 7pzS6p7/HOx6RrwXrMpHE3tIKiZW4S6+ZxvM49/bAxA8debbaqH1PdwJNBqEz/Mb jzfuabD2UKIARYsGVn+/xbpWn53jvK59guIBT1be8RqmXyp8jnyBjmO68N483nmj zcT3qJsQySMSPi4gf0P7UkNTaMUa5OyVmfF7PkY+HrUxHNRiC5nV6isW/vtQh1vv 4xKZimC2cihKE2S3+sounfChmFSzUZrwgeTDCq6iWvA2nY6gGljOh2WNyplkSHy4 DCDBb7ZWYWSAWnku4mkMpCsaPBHoYdq++JVW+xWvXLkJHBkXSIPgWCAGjwmGPfjC bU7lZcudGQ== =FAwZ -----END PGP SIGNATURE----- Merge tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Summary of modules changes for the 5.11 merge window: - Fix a race condition between systemd/udev and the module loader. The module loader was sending a uevent before the module was fully initialized (i.e., before its init function has been called). This means udev can start processing the module uevent before the module has finished initializing, and some udev rules expect that the module has initialized already upon receiving the uevent. This resulted in some systemd mount units failing if udev processes the event faster than the module can finish init. This is fixed by delaying the uevent until after the module has called its init routine. - Make the linker array sections for kernel params and module version attributes more robust by switching to use the alignment of the type in question. Namely, linker section arrays will be constructed using the alignment required by the struct (using __alignof__()) as opposed to a specific value such as sizeof(void *) or sizeof(long). This is less likely to cause breakages should the size of the type ever change (Johan Hovold) - Fix module state inconsistency by setting it back to GOING when a module fails to load and is on its way out (Miroslav Benes) - Some comment and code cleanups (Sergey Shtylyov)" * tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: delay kobject uevent until after module init call module: drop semicolon from version macro init: use type alignment for kernel parameters params: clean up module-param macros params: use type alignment for kernel parameters params: drop redundant "unused" attributes module: simplify version-attribute handling module: drop version-attribute alignment module: fix comment style module: add more 'kernel-doc' comments module: fix up 'kernel-doc' comments module: only handle errors with the *switch* statement in module_sig_check() module: avoid *goto*s in module_sig_check() module: merge repetitive strings in module_sig_check() module: set MODULE_STATE_GOING state when a module fails to load
958 lines
23 KiB
C
958 lines
23 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* Helpers for initial module or kernel cmdline parsing
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Copyright (C) 2001 Rusty Russell.
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*/
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/slab.h>
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#include <linux/ctype.h>
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#include <linux/security.h>
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#ifdef CONFIG_SYSFS
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/* Protects all built-in parameters, modules use their own param_lock */
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static DEFINE_MUTEX(param_lock);
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/* Use the module's mutex, or if built-in use the built-in mutex */
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#ifdef CONFIG_MODULES
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#define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : ¶m_lock)
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#else
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#define KPARAM_MUTEX(mod) (¶m_lock)
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#endif
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static inline void check_kparam_locked(struct module *mod)
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{
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BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod)));
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}
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#else
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static inline void check_kparam_locked(struct module *mod)
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{
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}
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#endif /* !CONFIG_SYSFS */
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/* This just allows us to keep track of which parameters are kmalloced. */
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struct kmalloced_param {
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struct list_head list;
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char val[];
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};
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static LIST_HEAD(kmalloced_params);
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static DEFINE_SPINLOCK(kmalloced_params_lock);
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static void *kmalloc_parameter(unsigned int size)
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{
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struct kmalloced_param *p;
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p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
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if (!p)
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return NULL;
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spin_lock(&kmalloced_params_lock);
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list_add(&p->list, &kmalloced_params);
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spin_unlock(&kmalloced_params_lock);
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return p->val;
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}
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/* Does nothing if parameter wasn't kmalloced above. */
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static void maybe_kfree_parameter(void *param)
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{
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struct kmalloced_param *p;
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spin_lock(&kmalloced_params_lock);
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list_for_each_entry(p, &kmalloced_params, list) {
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if (p->val == param) {
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list_del(&p->list);
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kfree(p);
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break;
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}
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}
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spin_unlock(&kmalloced_params_lock);
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}
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static char dash2underscore(char c)
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{
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if (c == '-')
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return '_';
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return c;
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}
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bool parameqn(const char *a, const char *b, size_t n)
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{
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size_t i;
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for (i = 0; i < n; i++) {
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if (dash2underscore(a[i]) != dash2underscore(b[i]))
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return false;
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}
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return true;
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}
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bool parameq(const char *a, const char *b)
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{
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return parameqn(a, b, strlen(a)+1);
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}
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static bool param_check_unsafe(const struct kernel_param *kp)
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{
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if (kp->flags & KERNEL_PARAM_FL_HWPARAM &&
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security_locked_down(LOCKDOWN_MODULE_PARAMETERS))
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return false;
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if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
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pr_notice("Setting dangerous option %s - tainting kernel\n",
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kp->name);
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add_taint(TAINT_USER, LOCKDEP_STILL_OK);
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}
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return true;
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}
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static int parse_one(char *param,
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char *val,
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const char *doing,
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const struct kernel_param *params,
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unsigned num_params,
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s16 min_level,
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s16 max_level,
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void *arg,
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int (*handle_unknown)(char *param, char *val,
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const char *doing, void *arg))
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{
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unsigned int i;
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int err;
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/* Find parameter */
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for (i = 0; i < num_params; i++) {
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if (parameq(param, params[i].name)) {
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if (params[i].level < min_level
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|| params[i].level > max_level)
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return 0;
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/* No one handled NULL, so do it here. */
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if (!val &&
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!(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG))
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return -EINVAL;
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pr_debug("handling %s with %p\n", param,
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params[i].ops->set);
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kernel_param_lock(params[i].mod);
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if (param_check_unsafe(¶ms[i]))
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err = params[i].ops->set(val, ¶ms[i]);
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else
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err = -EPERM;
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kernel_param_unlock(params[i].mod);
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return err;
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}
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}
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if (handle_unknown) {
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pr_debug("doing %s: %s='%s'\n", doing, param, val);
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return handle_unknown(param, val, doing, arg);
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}
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pr_debug("Unknown argument '%s'\n", param);
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return -ENOENT;
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}
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/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
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char *parse_args(const char *doing,
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char *args,
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const struct kernel_param *params,
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unsigned num,
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s16 min_level,
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s16 max_level,
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void *arg,
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int (*unknown)(char *param, char *val,
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const char *doing, void *arg))
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{
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char *param, *val, *err = NULL;
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/* Chew leading spaces */
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args = skip_spaces(args);
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if (*args)
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pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
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while (*args) {
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int ret;
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int irq_was_disabled;
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args = next_arg(args, ¶m, &val);
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/* Stop at -- */
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if (!val && strcmp(param, "--") == 0)
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return err ?: args;
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irq_was_disabled = irqs_disabled();
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ret = parse_one(param, val, doing, params, num,
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min_level, max_level, arg, unknown);
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if (irq_was_disabled && !irqs_disabled())
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pr_warn("%s: option '%s' enabled irq's!\n",
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doing, param);
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switch (ret) {
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case 0:
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continue;
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case -ENOENT:
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pr_err("%s: Unknown parameter `%s'\n", doing, param);
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break;
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case -ENOSPC:
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pr_err("%s: `%s' too large for parameter `%s'\n",
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doing, val ?: "", param);
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break;
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default:
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pr_err("%s: `%s' invalid for parameter `%s'\n",
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doing, val ?: "", param);
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break;
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}
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err = ERR_PTR(ret);
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}
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return err;
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}
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/* Lazy bastard, eh? */
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#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \
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int param_set_##name(const char *val, const struct kernel_param *kp) \
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{ \
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return strtolfn(val, 0, (type *)kp->arg); \
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} \
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int param_get_##name(char *buffer, const struct kernel_param *kp) \
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{ \
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return scnprintf(buffer, PAGE_SIZE, format "\n", \
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*((type *)kp->arg)); \
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} \
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const struct kernel_param_ops param_ops_##name = { \
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.set = param_set_##name, \
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.get = param_get_##name, \
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}; \
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EXPORT_SYMBOL(param_set_##name); \
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EXPORT_SYMBOL(param_get_##name); \
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EXPORT_SYMBOL(param_ops_##name)
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STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8);
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STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16);
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STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16);
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STANDARD_PARAM_DEF(int, int, "%i", kstrtoint);
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STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint);
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STANDARD_PARAM_DEF(long, long, "%li", kstrtol);
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STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul);
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STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull);
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STANDARD_PARAM_DEF(hexint, unsigned int, "%#08x", kstrtouint);
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int param_set_charp(const char *val, const struct kernel_param *kp)
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{
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if (strlen(val) > 1024) {
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pr_err("%s: string parameter too long\n", kp->name);
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return -ENOSPC;
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}
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maybe_kfree_parameter(*(char **)kp->arg);
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/* This is a hack. We can't kmalloc in early boot, and we
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* don't need to; this mangled commandline is preserved. */
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if (slab_is_available()) {
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*(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
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if (!*(char **)kp->arg)
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return -ENOMEM;
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strcpy(*(char **)kp->arg, val);
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} else
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*(const char **)kp->arg = val;
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return 0;
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}
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EXPORT_SYMBOL(param_set_charp);
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int param_get_charp(char *buffer, const struct kernel_param *kp)
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{
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return scnprintf(buffer, PAGE_SIZE, "%s\n", *((char **)kp->arg));
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}
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EXPORT_SYMBOL(param_get_charp);
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void param_free_charp(void *arg)
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{
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maybe_kfree_parameter(*((char **)arg));
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}
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EXPORT_SYMBOL(param_free_charp);
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const struct kernel_param_ops param_ops_charp = {
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.set = param_set_charp,
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.get = param_get_charp,
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.free = param_free_charp,
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};
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EXPORT_SYMBOL(param_ops_charp);
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/* Actually could be a bool or an int, for historical reasons. */
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int param_set_bool(const char *val, const struct kernel_param *kp)
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{
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/* No equals means "set"... */
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if (!val) val = "1";
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/* One of =[yYnN01] */
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return strtobool(val, kp->arg);
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}
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EXPORT_SYMBOL(param_set_bool);
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int param_get_bool(char *buffer, const struct kernel_param *kp)
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{
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/* Y and N chosen as being relatively non-coder friendly */
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return sprintf(buffer, "%c\n", *(bool *)kp->arg ? 'Y' : 'N');
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}
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EXPORT_SYMBOL(param_get_bool);
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const struct kernel_param_ops param_ops_bool = {
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.flags = KERNEL_PARAM_OPS_FL_NOARG,
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.set = param_set_bool,
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.get = param_get_bool,
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};
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EXPORT_SYMBOL(param_ops_bool);
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int param_set_bool_enable_only(const char *val, const struct kernel_param *kp)
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{
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int err = 0;
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bool new_value;
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bool orig_value = *(bool *)kp->arg;
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struct kernel_param dummy_kp = *kp;
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dummy_kp.arg = &new_value;
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err = param_set_bool(val, &dummy_kp);
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if (err)
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return err;
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/* Don't let them unset it once it's set! */
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if (!new_value && orig_value)
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return -EROFS;
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if (new_value)
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err = param_set_bool(val, kp);
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return err;
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}
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EXPORT_SYMBOL_GPL(param_set_bool_enable_only);
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const struct kernel_param_ops param_ops_bool_enable_only = {
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.flags = KERNEL_PARAM_OPS_FL_NOARG,
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.set = param_set_bool_enable_only,
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.get = param_get_bool,
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};
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EXPORT_SYMBOL_GPL(param_ops_bool_enable_only);
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/* This one must be bool. */
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int param_set_invbool(const char *val, const struct kernel_param *kp)
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{
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int ret;
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bool boolval;
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struct kernel_param dummy;
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dummy.arg = &boolval;
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ret = param_set_bool(val, &dummy);
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if (ret == 0)
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*(bool *)kp->arg = !boolval;
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return ret;
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}
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EXPORT_SYMBOL(param_set_invbool);
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int param_get_invbool(char *buffer, const struct kernel_param *kp)
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{
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return sprintf(buffer, "%c\n", (*(bool *)kp->arg) ? 'N' : 'Y');
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}
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EXPORT_SYMBOL(param_get_invbool);
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const struct kernel_param_ops param_ops_invbool = {
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.set = param_set_invbool,
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.get = param_get_invbool,
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};
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EXPORT_SYMBOL(param_ops_invbool);
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int param_set_bint(const char *val, const struct kernel_param *kp)
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{
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/* Match bool exactly, by re-using it. */
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struct kernel_param boolkp = *kp;
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bool v;
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int ret;
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boolkp.arg = &v;
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ret = param_set_bool(val, &boolkp);
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if (ret == 0)
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*(int *)kp->arg = v;
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return ret;
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}
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EXPORT_SYMBOL(param_set_bint);
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const struct kernel_param_ops param_ops_bint = {
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.flags = KERNEL_PARAM_OPS_FL_NOARG,
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.set = param_set_bint,
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.get = param_get_int,
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};
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EXPORT_SYMBOL(param_ops_bint);
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/* We break the rule and mangle the string. */
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static int param_array(struct module *mod,
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const char *name,
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const char *val,
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unsigned int min, unsigned int max,
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void *elem, int elemsize,
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int (*set)(const char *, const struct kernel_param *kp),
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s16 level,
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unsigned int *num)
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{
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int ret;
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struct kernel_param kp;
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char save;
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/* Get the name right for errors. */
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kp.name = name;
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kp.arg = elem;
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kp.level = level;
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*num = 0;
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/* We expect a comma-separated list of values. */
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do {
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int len;
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if (*num == max) {
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pr_err("%s: can only take %i arguments\n", name, max);
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return -EINVAL;
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}
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len = strcspn(val, ",");
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/* nul-terminate and parse */
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save = val[len];
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((char *)val)[len] = '\0';
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check_kparam_locked(mod);
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ret = set(val, &kp);
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if (ret != 0)
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return ret;
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kp.arg += elemsize;
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val += len+1;
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(*num)++;
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} while (save == ',');
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|
|
|
if (*num < min) {
|
|
pr_err("%s: needs at least %i arguments\n", name, min);
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int param_array_set(const char *val, const struct kernel_param *kp)
|
|
{
|
|
const struct kparam_array *arr = kp->arr;
|
|
unsigned int temp_num;
|
|
|
|
return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem,
|
|
arr->elemsize, arr->ops->set, kp->level,
|
|
arr->num ?: &temp_num);
|
|
}
|
|
|
|
static int param_array_get(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
int i, off, ret;
|
|
const struct kparam_array *arr = kp->arr;
|
|
struct kernel_param p = *kp;
|
|
|
|
for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
|
|
/* Replace \n with comma */
|
|
if (i)
|
|
buffer[off - 1] = ',';
|
|
p.arg = arr->elem + arr->elemsize * i;
|
|
check_kparam_locked(p.mod);
|
|
ret = arr->ops->get(buffer + off, &p);
|
|
if (ret < 0)
|
|
return ret;
|
|
off += ret;
|
|
}
|
|
buffer[off] = '\0';
|
|
return off;
|
|
}
|
|
|
|
static void param_array_free(void *arg)
|
|
{
|
|
unsigned int i;
|
|
const struct kparam_array *arr = arg;
|
|
|
|
if (arr->ops->free)
|
|
for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
|
|
arr->ops->free(arr->elem + arr->elemsize * i);
|
|
}
|
|
|
|
const struct kernel_param_ops param_array_ops = {
|
|
.set = param_array_set,
|
|
.get = param_array_get,
|
|
.free = param_array_free,
|
|
};
|
|
EXPORT_SYMBOL(param_array_ops);
|
|
|
|
int param_set_copystring(const char *val, const struct kernel_param *kp)
|
|
{
|
|
const struct kparam_string *kps = kp->str;
|
|
|
|
if (strlen(val)+1 > kps->maxlen) {
|
|
pr_err("%s: string doesn't fit in %u chars.\n",
|
|
kp->name, kps->maxlen-1);
|
|
return -ENOSPC;
|
|
}
|
|
strcpy(kps->string, val);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(param_set_copystring);
|
|
|
|
int param_get_string(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
const struct kparam_string *kps = kp->str;
|
|
return scnprintf(buffer, PAGE_SIZE, "%s\n", kps->string);
|
|
}
|
|
EXPORT_SYMBOL(param_get_string);
|
|
|
|
const struct kernel_param_ops param_ops_string = {
|
|
.set = param_set_copystring,
|
|
.get = param_get_string,
|
|
};
|
|
EXPORT_SYMBOL(param_ops_string);
|
|
|
|
/* sysfs output in /sys/modules/XYZ/parameters/ */
|
|
#define to_module_attr(n) container_of(n, struct module_attribute, attr)
|
|
#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
|
|
|
|
struct param_attribute
|
|
{
|
|
struct module_attribute mattr;
|
|
const struct kernel_param *param;
|
|
};
|
|
|
|
struct module_param_attrs
|
|
{
|
|
unsigned int num;
|
|
struct attribute_group grp;
|
|
struct param_attribute attrs[];
|
|
};
|
|
|
|
#ifdef CONFIG_SYSFS
|
|
#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
|
|
|
|
static ssize_t param_attr_show(struct module_attribute *mattr,
|
|
struct module_kobject *mk, char *buf)
|
|
{
|
|
int count;
|
|
struct param_attribute *attribute = to_param_attr(mattr);
|
|
|
|
if (!attribute->param->ops->get)
|
|
return -EPERM;
|
|
|
|
kernel_param_lock(mk->mod);
|
|
count = attribute->param->ops->get(buf, attribute->param);
|
|
kernel_param_unlock(mk->mod);
|
|
return count;
|
|
}
|
|
|
|
/* sysfs always hands a nul-terminated string in buf. We rely on that. */
|
|
static ssize_t param_attr_store(struct module_attribute *mattr,
|
|
struct module_kobject *mk,
|
|
const char *buf, size_t len)
|
|
{
|
|
int err;
|
|
struct param_attribute *attribute = to_param_attr(mattr);
|
|
|
|
if (!attribute->param->ops->set)
|
|
return -EPERM;
|
|
|
|
kernel_param_lock(mk->mod);
|
|
if (param_check_unsafe(attribute->param))
|
|
err = attribute->param->ops->set(buf, attribute->param);
|
|
else
|
|
err = -EPERM;
|
|
kernel_param_unlock(mk->mod);
|
|
if (!err)
|
|
return len;
|
|
return err;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MODULES
|
|
#define __modinit
|
|
#else
|
|
#define __modinit __init
|
|
#endif
|
|
|
|
#ifdef CONFIG_SYSFS
|
|
void kernel_param_lock(struct module *mod)
|
|
{
|
|
mutex_lock(KPARAM_MUTEX(mod));
|
|
}
|
|
|
|
void kernel_param_unlock(struct module *mod)
|
|
{
|
|
mutex_unlock(KPARAM_MUTEX(mod));
|
|
}
|
|
|
|
EXPORT_SYMBOL(kernel_param_lock);
|
|
EXPORT_SYMBOL(kernel_param_unlock);
|
|
|
|
/*
|
|
* add_sysfs_param - add a parameter to sysfs
|
|
* @mk: struct module_kobject
|
|
* @kp: the actual parameter definition to add to sysfs
|
|
* @name: name of parameter
|
|
*
|
|
* Create a kobject if for a (per-module) parameter if mp NULL, and
|
|
* create file in sysfs. Returns an error on out of memory. Always cleans up
|
|
* if there's an error.
|
|
*/
|
|
static __modinit int add_sysfs_param(struct module_kobject *mk,
|
|
const struct kernel_param *kp,
|
|
const char *name)
|
|
{
|
|
struct module_param_attrs *new_mp;
|
|
struct attribute **new_attrs;
|
|
unsigned int i;
|
|
|
|
/* We don't bother calling this with invisible parameters. */
|
|
BUG_ON(!kp->perm);
|
|
|
|
if (!mk->mp) {
|
|
/* First allocation. */
|
|
mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL);
|
|
if (!mk->mp)
|
|
return -ENOMEM;
|
|
mk->mp->grp.name = "parameters";
|
|
/* NULL-terminated attribute array. */
|
|
mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]),
|
|
GFP_KERNEL);
|
|
/* Caller will cleanup via free_module_param_attrs */
|
|
if (!mk->mp->grp.attrs)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Enlarge allocations. */
|
|
new_mp = krealloc(mk->mp,
|
|
sizeof(*mk->mp) +
|
|
sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1),
|
|
GFP_KERNEL);
|
|
if (!new_mp)
|
|
return -ENOMEM;
|
|
mk->mp = new_mp;
|
|
|
|
/* Extra pointer for NULL terminator */
|
|
new_attrs = krealloc(mk->mp->grp.attrs,
|
|
sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2),
|
|
GFP_KERNEL);
|
|
if (!new_attrs)
|
|
return -ENOMEM;
|
|
mk->mp->grp.attrs = new_attrs;
|
|
|
|
/* Tack new one on the end. */
|
|
memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0]));
|
|
sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr);
|
|
mk->mp->attrs[mk->mp->num].param = kp;
|
|
mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show;
|
|
/* Do not allow runtime DAC changes to make param writable. */
|
|
if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0)
|
|
mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store;
|
|
else
|
|
mk->mp->attrs[mk->mp->num].mattr.store = NULL;
|
|
mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name;
|
|
mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm;
|
|
mk->mp->num++;
|
|
|
|
/* Fix up all the pointers, since krealloc can move us */
|
|
for (i = 0; i < mk->mp->num; i++)
|
|
mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr;
|
|
mk->mp->grp.attrs[mk->mp->num] = NULL;
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_MODULES
|
|
static void free_module_param_attrs(struct module_kobject *mk)
|
|
{
|
|
if (mk->mp)
|
|
kfree(mk->mp->grp.attrs);
|
|
kfree(mk->mp);
|
|
mk->mp = NULL;
|
|
}
|
|
|
|
/*
|
|
* module_param_sysfs_setup - setup sysfs support for one module
|
|
* @mod: module
|
|
* @kparam: module parameters (array)
|
|
* @num_params: number of module parameters
|
|
*
|
|
* Adds sysfs entries for module parameters under
|
|
* /sys/module/[mod->name]/parameters/
|
|
*/
|
|
int module_param_sysfs_setup(struct module *mod,
|
|
const struct kernel_param *kparam,
|
|
unsigned int num_params)
|
|
{
|
|
int i, err;
|
|
bool params = false;
|
|
|
|
for (i = 0; i < num_params; i++) {
|
|
if (kparam[i].perm == 0)
|
|
continue;
|
|
err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
|
|
if (err) {
|
|
free_module_param_attrs(&mod->mkobj);
|
|
return err;
|
|
}
|
|
params = true;
|
|
}
|
|
|
|
if (!params)
|
|
return 0;
|
|
|
|
/* Create the param group. */
|
|
err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
|
|
if (err)
|
|
free_module_param_attrs(&mod->mkobj);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* module_param_sysfs_remove - remove sysfs support for one module
|
|
* @mod: module
|
|
*
|
|
* Remove sysfs entries for module parameters and the corresponding
|
|
* kobject.
|
|
*/
|
|
void module_param_sysfs_remove(struct module *mod)
|
|
{
|
|
if (mod->mkobj.mp) {
|
|
sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
|
|
/* We are positive that no one is using any param
|
|
* attrs at this point. Deallocate immediately. */
|
|
free_module_param_attrs(&mod->mkobj);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
void destroy_params(const struct kernel_param *params, unsigned num)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < num; i++)
|
|
if (params[i].ops->free)
|
|
params[i].ops->free(params[i].arg);
|
|
}
|
|
|
|
static struct module_kobject * __init locate_module_kobject(const char *name)
|
|
{
|
|
struct module_kobject *mk;
|
|
struct kobject *kobj;
|
|
int err;
|
|
|
|
kobj = kset_find_obj(module_kset, name);
|
|
if (kobj) {
|
|
mk = to_module_kobject(kobj);
|
|
} else {
|
|
mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
|
|
BUG_ON(!mk);
|
|
|
|
mk->mod = THIS_MODULE;
|
|
mk->kobj.kset = module_kset;
|
|
err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
|
|
"%s", name);
|
|
#ifdef CONFIG_MODULES
|
|
if (!err)
|
|
err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
|
|
#endif
|
|
if (err) {
|
|
kobject_put(&mk->kobj);
|
|
pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
|
|
name, err);
|
|
return NULL;
|
|
}
|
|
|
|
/* So that we hold reference in both cases. */
|
|
kobject_get(&mk->kobj);
|
|
}
|
|
|
|
return mk;
|
|
}
|
|
|
|
static void __init kernel_add_sysfs_param(const char *name,
|
|
const struct kernel_param *kparam,
|
|
unsigned int name_skip)
|
|
{
|
|
struct module_kobject *mk;
|
|
int err;
|
|
|
|
mk = locate_module_kobject(name);
|
|
if (!mk)
|
|
return;
|
|
|
|
/* We need to remove old parameters before adding more. */
|
|
if (mk->mp)
|
|
sysfs_remove_group(&mk->kobj, &mk->mp->grp);
|
|
|
|
/* These should not fail at boot. */
|
|
err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
|
|
BUG_ON(err);
|
|
err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
|
|
BUG_ON(err);
|
|
kobject_uevent(&mk->kobj, KOBJ_ADD);
|
|
kobject_put(&mk->kobj);
|
|
}
|
|
|
|
/*
|
|
* param_sysfs_builtin - add sysfs parameters for built-in modules
|
|
*
|
|
* Add module_parameters to sysfs for "modules" built into the kernel.
|
|
*
|
|
* The "module" name (KBUILD_MODNAME) is stored before a dot, the
|
|
* "parameter" name is stored behind a dot in kernel_param->name. So,
|
|
* extract the "module" name for all built-in kernel_param-eters,
|
|
* and for all who have the same, call kernel_add_sysfs_param.
|
|
*/
|
|
static void __init param_sysfs_builtin(void)
|
|
{
|
|
const struct kernel_param *kp;
|
|
unsigned int name_len;
|
|
char modname[MODULE_NAME_LEN];
|
|
|
|
for (kp = __start___param; kp < __stop___param; kp++) {
|
|
char *dot;
|
|
|
|
if (kp->perm == 0)
|
|
continue;
|
|
|
|
dot = strchr(kp->name, '.');
|
|
if (!dot) {
|
|
/* This happens for core_param() */
|
|
strcpy(modname, "kernel");
|
|
name_len = 0;
|
|
} else {
|
|
name_len = dot - kp->name + 1;
|
|
strlcpy(modname, kp->name, name_len);
|
|
}
|
|
kernel_add_sysfs_param(modname, kp, name_len);
|
|
}
|
|
}
|
|
|
|
ssize_t __modver_version_show(struct module_attribute *mattr,
|
|
struct module_kobject *mk, char *buf)
|
|
{
|
|
struct module_version_attribute *vattr =
|
|
container_of(mattr, struct module_version_attribute, mattr);
|
|
|
|
return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
|
|
}
|
|
|
|
extern const struct module_version_attribute __start___modver[];
|
|
extern const struct module_version_attribute __stop___modver[];
|
|
|
|
static void __init version_sysfs_builtin(void)
|
|
{
|
|
const struct module_version_attribute *vattr;
|
|
struct module_kobject *mk;
|
|
int err;
|
|
|
|
for (vattr = __start___modver; vattr < __stop___modver; vattr++) {
|
|
mk = locate_module_kobject(vattr->module_name);
|
|
if (mk) {
|
|
err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
|
|
WARN_ON_ONCE(err);
|
|
kobject_uevent(&mk->kobj, KOBJ_ADD);
|
|
kobject_put(&mk->kobj);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* module-related sysfs stuff */
|
|
|
|
static ssize_t module_attr_show(struct kobject *kobj,
|
|
struct attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct module_attribute *attribute;
|
|
struct module_kobject *mk;
|
|
int ret;
|
|
|
|
attribute = to_module_attr(attr);
|
|
mk = to_module_kobject(kobj);
|
|
|
|
if (!attribute->show)
|
|
return -EIO;
|
|
|
|
ret = attribute->show(attribute, mk, buf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t module_attr_store(struct kobject *kobj,
|
|
struct attribute *attr,
|
|
const char *buf, size_t len)
|
|
{
|
|
struct module_attribute *attribute;
|
|
struct module_kobject *mk;
|
|
int ret;
|
|
|
|
attribute = to_module_attr(attr);
|
|
mk = to_module_kobject(kobj);
|
|
|
|
if (!attribute->store)
|
|
return -EIO;
|
|
|
|
ret = attribute->store(attribute, mk, buf, len);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct sysfs_ops module_sysfs_ops = {
|
|
.show = module_attr_show,
|
|
.store = module_attr_store,
|
|
};
|
|
|
|
static int uevent_filter(struct kset *kset, struct kobject *kobj)
|
|
{
|
|
struct kobj_type *ktype = get_ktype(kobj);
|
|
|
|
if (ktype == &module_ktype)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static const struct kset_uevent_ops module_uevent_ops = {
|
|
.filter = uevent_filter,
|
|
};
|
|
|
|
struct kset *module_kset;
|
|
int module_sysfs_initialized;
|
|
|
|
static void module_kobj_release(struct kobject *kobj)
|
|
{
|
|
struct module_kobject *mk = to_module_kobject(kobj);
|
|
complete(mk->kobj_completion);
|
|
}
|
|
|
|
struct kobj_type module_ktype = {
|
|
.release = module_kobj_release,
|
|
.sysfs_ops = &module_sysfs_ops,
|
|
};
|
|
|
|
/*
|
|
* param_sysfs_init - wrapper for built-in params support
|
|
*/
|
|
static int __init param_sysfs_init(void)
|
|
{
|
|
module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
|
|
if (!module_kset) {
|
|
printk(KERN_WARNING "%s (%d): error creating kset\n",
|
|
__FILE__, __LINE__);
|
|
return -ENOMEM;
|
|
}
|
|
module_sysfs_initialized = 1;
|
|
|
|
version_sysfs_builtin();
|
|
param_sysfs_builtin();
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(param_sysfs_init);
|
|
|
|
#endif /* CONFIG_SYSFS */
|