From 22098763a10d9c1340827fcf6edab66f153b27f0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 13 Sep 2026 12:27:00 -0700 Subject: Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ... --- fs/char_dev.c | 689 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 689 insertions(+) create mode 100644 fs/char_dev.c (limited to 'fs/char_dev.c') diff --git a/fs/char_dev.c b/fs/char_dev.c new file mode 100644 index 000000000..00229e25c --- /dev/null +++ b/fs/char_dev.c @@ -0,0 +1,689 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/char_dev.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + */ + +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +static struct kobj_map *cdev_map __ro_after_init; + +static DEFINE_MUTEX(chrdevs_lock); + +#define CHRDEV_MAJOR_HASH_SIZE 255 + +static struct char_device_struct { + struct char_device_struct *next; + unsigned int major; + unsigned int baseminor; + int minorct; + char name[64]; + struct cdev *cdev; /* will die */ +} *chrdevs[CHRDEV_MAJOR_HASH_SIZE]; + +/* index in the above */ +static inline int major_to_index(unsigned major) +{ + return major % CHRDEV_MAJOR_HASH_SIZE; +} + +#ifdef CONFIG_PROC_FS + +void chrdev_show(struct seq_file *f, off_t offset) +{ + struct char_device_struct *cd; + + mutex_lock(&chrdevs_lock); + for (cd = chrdevs[major_to_index(offset)]; cd; cd = cd->next) { + if (cd->major == offset) + seq_printf(f, "%3d %s\n", cd->major, cd->name); + } + mutex_unlock(&chrdevs_lock); +} + +#endif /* CONFIG_PROC_FS */ + +static int find_dynamic_major(void) +{ + int i; + struct char_device_struct *cd; + + for (i = ARRAY_SIZE(chrdevs)-1; i >= CHRDEV_MAJOR_DYN_END; i--) { + if (chrdevs[i] == NULL) + return i; + } + + for (i = CHRDEV_MAJOR_DYN_EXT_START; + i >= CHRDEV_MAJOR_DYN_EXT_END; i--) { + for (cd = chrdevs[major_to_index(i)]; cd; cd = cd->next) + if (cd->major == i) + break; + + if (cd == NULL) + return i; + } + + return -EBUSY; +} + +/* + * Register a single major with a specified minor range. + * + * If major == 0 this function will dynamically allocate an unused major. + * If major > 0 this function will attempt to reserve the range of minors + * with given major. + * + */ +static struct char_device_struct * +__register_chrdev_region(unsigned int major, unsigned int baseminor, + int minorct, const char *name) +{ + struct char_device_struct *cd __free(kfree) = NULL; + struct char_device_struct *curr, *prev = NULL; + int ret; + int i; + + if (major >= CHRDEV_MAJOR_MAX) { + pr_err("CHRDEV \"%s\" major requested (%u) is greater than the maximum (%u)\n", + name, major, CHRDEV_MAJOR_MAX-1); + return ERR_PTR(-EINVAL); + } + + if (minorct > MINORMASK + 1 - baseminor) { + pr_err("CHRDEV \"%s\" minor range requested (%u-%u) is out of range of maximum range (%u-%u) for a single major\n", + name, baseminor, baseminor + minorct - 1, 0, MINORMASK); + return ERR_PTR(-EINVAL); + } + + cd = kzalloc_obj(struct char_device_struct); + if (cd == NULL) + return ERR_PTR(-ENOMEM); + + guard(mutex)(&chrdevs_lock); + + if (major == 0) { + ret = find_dynamic_major(); + if (ret < 0) { + pr_err("CHRDEV \"%s\" dynamic allocation region is full\n", + name); + return ERR_PTR(ret); + } + major = ret; + } + + ret = -EBUSY; + i = major_to_index(major); + for (curr = chrdevs[i]; curr; prev = curr, curr = curr->next) { + if (curr->major < major) + continue; + + if (curr->major > major) + break; + + if (curr->baseminor + curr->minorct <= baseminor) + continue; + + if (curr->baseminor >= baseminor + minorct) + break; + + return ERR_PTR(ret); + } + + cd->major = major; + cd->baseminor = baseminor; + cd->minorct = minorct; + strscpy(cd->name, name, sizeof(cd->name)); + + if (!prev) { + cd->next = curr; + chrdevs[i] = cd; + } else { + cd->next = prev->next; + prev->next = cd; + } + + return_ptr(cd); +} + +static struct char_device_struct * +__unregister_chrdev_region(unsigned major, unsigned baseminor, int minorct) +{ + struct char_device_struct *cd = NULL, **cp; + int i = major_to_index(major); + + mutex_lock(&chrdevs_lock); + for (cp = &chrdevs[i]; *cp; cp = &(*cp)->next) + if ((*cp)->major == major && + (*cp)->baseminor == baseminor && + (*cp)->minorct == minorct) + break; + if (*cp) { + cd = *cp; + *cp = cd->next; + } + mutex_unlock(&chrdevs_lock); + return cd; +} + +/** + * register_chrdev_region() - register a range of device numbers + * @from: the first in the desired range of device numbers; must include + * the major number. + * @count: the number of consecutive device numbers required + * @name: the name of the device or driver. + * + * Return value is zero on success, a negative error code on failure. + */ +int register_chrdev_region(dev_t from, unsigned count, const char *name) +{ + struct char_device_struct *cd; + dev_t to = from + count; + dev_t n, next; + + for (n = from; n < to; n = next) { + next = MKDEV(MAJOR(n)+1, 0); + if (next > to) + next = to; + cd = __register_chrdev_region(MAJOR(n), MINOR(n), + next - n, name); + if (IS_ERR(cd)) + goto fail; + } + return 0; +fail: + to = n; + for (n = from; n < to; n = next) { + next = MKDEV(MAJOR(n)+1, 0); + kfree(__unregister_chrdev_region(MAJOR(n), MINOR(n), next - n)); + } + return PTR_ERR(cd); +} + +/** + * alloc_chrdev_region() - register a range of char device numbers + * @dev: output parameter for first assigned number + * @baseminor: first of the requested range of minor numbers + * @count: the number of minor numbers required + * @name: the name of the associated device or driver + * + * Allocates a range of char device numbers. The major number will be + * chosen dynamically, and returned (along with the first minor number) + * in @dev. Returns zero or a negative error code. + */ +int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count, + const char *name) +{ + struct char_device_struct *cd; + cd = __register_chrdev_region(0, baseminor, count, name); + if (IS_ERR(cd)) + return PTR_ERR(cd); + *dev = MKDEV(cd->major, cd->baseminor); + return 0; +} + +/** + * __register_chrdev() - create and register a cdev occupying a range of minors + * @major: major device number or 0 for dynamic allocation + * @baseminor: first of the requested range of minor numbers + * @count: the number of minor numbers required + * @name: name of this range of devices + * @fops: file operations associated with this devices + * + * If @major == 0 this functions will dynamically allocate a major and return + * its number. + * + * If @major > 0 this function will attempt to reserve a device with the given + * major number and will return zero on success. + * + * Returns a -ve errno on failure. + * + * The name of this device has nothing to do with the name of the device in + * /dev. It only helps to keep track of the different owners of devices. If + * your module name has only one type of devices it's ok to use e.g. the name + * of the module here. + */ +int __register_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name, + const struct file_operations *fops) +{ + struct char_device_struct *cd; + struct cdev *cdev; + int err = -ENOMEM; + + cd = __register_chrdev_region(major, baseminor, count, name); + if (IS_ERR(cd)) + return PTR_ERR(cd); + + cdev = cdev_alloc(); + if (!cdev) + goto out2; + + cdev->owner = fops->owner; + cdev->ops = fops; + kobject_set_name(&cdev->kobj, "%s", name); + + err = cdev_add(cdev, MKDEV(cd->major, baseminor), count); + if (err) + goto out; + + cd->cdev = cdev; + + return major ? 0 : cd->major; +out: + kobject_put(&cdev->kobj); +out2: + kfree(__unregister_chrdev_region(cd->major, baseminor, count)); + return err; +} + +/** + * unregister_chrdev_region() - unregister a range of device numbers + * @from: the first in the range of numbers to unregister + * @count: the number of device numbers to unregister + * + * This function will unregister a range of @count device numbers, + * starting with @from. The caller should normally be the one who + * allocated those numbers in the first place... + */ +void unregister_chrdev_region(dev_t from, unsigned count) +{ + dev_t to = from + count; + dev_t n, next; + + for (n = from; n < to; n = next) { + next = MKDEV(MAJOR(n)+1, 0); + if (next > to) + next = to; + kfree(__unregister_chrdev_region(MAJOR(n), MINOR(n), next - n)); + } +} + +/** + * __unregister_chrdev - unregister and destroy a cdev + * @major: major device number + * @baseminor: first of the range of minor numbers + * @count: the number of minor numbers this cdev is occupying + * @name: name of this range of devices + * + * Unregister and destroy the cdev occupying the region described by + * @major, @baseminor and @count. This function undoes what + * __register_chrdev() did. + */ +void __unregister_chrdev(unsigned int major, unsigned int baseminor, + unsigned int count, const char *name) +{ + struct char_device_struct *cd; + + cd = __unregister_chrdev_region(major, baseminor, count); + if (cd && cd->cdev) + cdev_del(cd->cdev); + kfree(cd); +} + +static __cacheline_aligned_in_smp DEFINE_SPINLOCK(cdev_lock); + +static struct kobject *cdev_get(struct cdev *p) +{ + struct module *owner = p->owner; + struct kobject *kobj; + + if (!try_module_get(owner)) + return NULL; + kobj = kobject_get_unless_zero(&p->kobj); + if (!kobj) + module_put(owner); + return kobj; +} + +void cdev_put(struct cdev *p) +{ + if (p) { + struct module *owner = p->owner; + kobject_put(&p->kobj); + module_put(owner); + } +} + +/* + * Called every time a character special file is opened + */ +static int chrdev_open(struct inode *inode, struct file *filp) +{ + const struct file_operations *fops; + struct cdev *p; + struct cdev *new = NULL; + int ret = 0; + + spin_lock(&cdev_lock); + p = inode->i_cdev; + if (!p) { + struct kobject *kobj; + int idx; + spin_unlock(&cdev_lock); + kobj = kobj_lookup(cdev_map, inode->i_rdev, &idx); + if (!kobj) + return -ENXIO; + new = container_of(kobj, struct cdev, kobj); + spin_lock(&cdev_lock); + /* Check i_cdev again in case somebody beat us to it while + we dropped the lock. */ + p = inode->i_cdev; + if (!p) { + inode->i_cdev = p = new; + list_add(&inode->i_devices, &p->list); + new = NULL; + } else if (!cdev_get(p)) + ret = -ENXIO; + } else if (!cdev_get(p)) + ret = -ENXIO; + spin_unlock(&cdev_lock); + cdev_put(new); + if (ret) + return ret; + + ret = -ENXIO; + fops = fops_get(p->ops); + if (!fops) + goto out_cdev_put; + + replace_fops(filp, fops); + if (filp->f_op->open) { + ret = filp->f_op->open(inode, filp); + if (ret) + goto out_cdev_put; + } + + return 0; + + out_cdev_put: + cdev_put(p); + return ret; +} + +void cd_forget(struct inode *inode) +{ + spin_lock(&cdev_lock); + list_del_init(&inode->i_devices); + inode->i_cdev = NULL; + inode->i_mapping = &inode->i_data; + spin_unlock(&cdev_lock); +} + +static void cdev_purge(struct cdev *cdev) +{ + spin_lock(&cdev_lock); + while (!list_empty(&cdev->list)) { + struct inode *inode; + inode = container_of(cdev->list.next, struct inode, i_devices); + list_del_init(&inode->i_devices); + inode->i_cdev = NULL; + } + spin_unlock(&cdev_lock); +} + +/* + * Dummy default file-operations: the only thing this does + * is contain the open that then fills in the correct operations + * depending on the special file... + */ +const struct file_operations def_chr_fops = { + .open = chrdev_open, + .llseek = noop_llseek, +}; + +static struct kobject *exact_match(dev_t dev, int *part, void *data) +{ + struct cdev *p = data; + return &p->kobj; +} + +static int exact_lock(dev_t dev, void *data) +{ + struct cdev *p = data; + return cdev_get(p) ? 0 : -1; +} + +/** + * cdev_add() - add a char device to the system + * @p: the cdev structure for the device + * @dev: the first device number for which this device is responsible + * @count: the number of consecutive minor numbers corresponding to this + * device + * + * cdev_add() adds the device represented by @p to the system, making it + * live immediately. A negative error code is returned on failure. + */ +int cdev_add(struct cdev *p, dev_t dev, unsigned count) +{ + int error; + + p->dev = dev; + p->count = count; + + if (WARN_ON(dev == WHITEOUT_DEV)) { + error = -EBUSY; + goto err; + } + + error = kobj_map(cdev_map, dev, count, NULL, + exact_match, exact_lock, p); + if (error) + goto err; + + kobject_get(p->kobj.parent); + + return 0; + +err: + kfree_const(p->kobj.name); + p->kobj.name = NULL; + return error; +} + +/** + * cdev_set_parent() - set the parent kobject for a char device + * @p: the cdev structure + * @kobj: the kobject to take a reference to + * + * cdev_set_parent() sets a parent kobject which will be referenced + * appropriately so the parent is not freed before the cdev. This + * should be called before cdev_add. + */ +void cdev_set_parent(struct cdev *p, struct kobject *kobj) +{ + WARN_ON(!kobj->state_initialized); + p->kobj.parent = kobj; +} + +/** + * cdev_device_add() - add a char device and it's corresponding + * struct device, linkink + * @dev: the device structure + * @cdev: the cdev structure + * + * cdev_device_add() adds the char device represented by @cdev to the system, + * just as cdev_add does. It then adds @dev to the system using device_add + * The dev_t for the char device will be taken from the struct device which + * needs to be initialized first. This helper function correctly takes a + * reference to the parent device so the parent will not get released until + * all references to the cdev are released. + * + * This helper uses dev->devt for the device number. If it is not set + * it will not add the cdev and it will be equivalent to device_add. + * + * This function should be used whenever the struct cdev and the + * struct device are members of the same structure whose lifetime is + * managed by the struct device. + * + * NOTE: Callers must assume that userspace was able to open the cdev and + * can call cdev fops callbacks at any time, even if this function fails. + */ +int cdev_device_add(struct cdev *cdev, struct device *dev) +{ + int rc = 0; + + if (dev->devt) { + cdev_set_parent(cdev, &dev->kobj); + + rc = cdev_add(cdev, dev->devt, 1); + if (rc) + return rc; + } + + rc = device_add(dev); + if (rc && dev->devt) + cdev_del(cdev); + + return rc; +} + +/** + * cdev_device_del() - inverse of cdev_device_add + * @cdev: the cdev structure + * @dev: the device structure + * + * cdev_device_del() is a helper function to call cdev_del and device_del. + * It should be used whenever cdev_device_add is used. + * + * If dev->devt is not set it will not remove the cdev and will be equivalent + * to device_del. + * + * NOTE: This guarantees that associated sysfs callbacks are not running + * or runnable, however any cdevs already open will remain and their fops + * will still be callable even after this function returns. + */ +void cdev_device_del(struct cdev *cdev, struct device *dev) +{ + device_del(dev); + if (dev->devt) + cdev_del(cdev); +} + +static void cdev_unmap(dev_t dev, unsigned count) +{ + kobj_unmap(cdev_map, dev, count); +} + +/** + * cdev_del() - remove a cdev from the system + * @p: the cdev structure to be removed + * + * cdev_del() removes @p from the system, possibly freeing the structure + * itself. + * + * NOTE: This guarantees that cdev device will no longer be able to be + * opened, however any cdevs already open will remain and their fops will + * still be callable even after cdev_del returns. + */ +void cdev_del(struct cdev *p) +{ + cdev_unmap(p->dev, p->count); + kobject_put(&p->kobj); +} + + +static void cdev_default_release(struct kobject *kobj) +{ + struct cdev *p = container_of(kobj, struct cdev, kobj); + struct kobject *parent = kobj->parent; + + cdev_purge(p); + kobject_put(parent); +} + +static void cdev_dynamic_release(struct kobject *kobj) +{ + struct cdev *p = container_of(kobj, struct cdev, kobj); + struct kobject *parent = kobj->parent; + + cdev_purge(p); + kfree(p); + kobject_put(parent); +} + +static struct kobj_type ktype_cdev_default = { + .release = cdev_default_release, +}; + +static struct kobj_type ktype_cdev_dynamic = { + .release = cdev_dynamic_release, +}; + +/** + * cdev_alloc() - allocate a cdev structure + * + * Allocates and returns a cdev structure, or NULL on failure. + */ +struct cdev *cdev_alloc(void) +{ + struct cdev *p = kzalloc_obj(struct cdev); + if (p) { + INIT_LIST_HEAD(&p->list); + kobject_init(&p->kobj, &ktype_cdev_dynamic); + } + return p; +} + +/** + * cdev_init() - initialize a cdev structure + * @cdev: the structure to initialize + * @fops: the file_operations for this device + * + * Initializes @cdev, remembering @fops, making it ready to add to the + * system with cdev_add(). + */ +void cdev_init(struct cdev *cdev, const struct file_operations *fops) +{ + memset(cdev, 0, sizeof *cdev); + INIT_LIST_HEAD(&cdev->list); + kobject_init(&cdev->kobj, &ktype_cdev_default); + cdev->ops = fops; +} + +static struct kobject *base_probe(dev_t dev, int *part, void *data) +{ + if (request_module("char-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0) + /* Make old-style 2.4 aliases work */ + request_module("char-major-%d", MAJOR(dev)); + return NULL; +} + +void __init chrdev_init(void) +{ + cdev_map = kobj_map_init(base_probe, &chrdevs_lock); +} + + +/* Let modules do char dev stuff */ +EXPORT_SYMBOL(register_chrdev_region); +EXPORT_SYMBOL(unregister_chrdev_region); +EXPORT_SYMBOL(alloc_chrdev_region); +EXPORT_SYMBOL(cdev_init); +EXPORT_SYMBOL(cdev_alloc); +EXPORT_SYMBOL(cdev_del); +EXPORT_SYMBOL(cdev_add); +EXPORT_SYMBOL(cdev_set_parent); +EXPORT_SYMBOL(cdev_device_add); +EXPORT_SYMBOL(cdev_device_del); +EXPORT_SYMBOL(__register_chrdev); +EXPORT_SYMBOL(__unregister_chrdev); -- cgit v1.3.1