X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fchar%2Fmisc.c;fp=kernel%2Fdrivers%2Fchar%2Fmisc.c;h=8069b361b8dd1ce2363afff0bf4eb6eef5e5fc1c;hb=e09b41010ba33a20a87472ee821fa407a5b8da36;hp=9fd5a91e0d81e4f5f2ec2abe714ca0d0ef88972c;hpb=f93b97fd65072de626c074dbe099a1fff05ce060;p=kvmfornfv.git diff --git a/kernel/drivers/char/misc.c b/kernel/drivers/char/misc.c index 9fd5a91e0..8069b361b 100644 --- a/kernel/drivers/char/misc.c +++ b/kernel/drivers/char/misc.c @@ -117,14 +117,14 @@ static int misc_open(struct inode * inode, struct file * file) const struct file_operations *new_fops = NULL; mutex_lock(&misc_mtx); - + list_for_each_entry(c, &misc_list, list) { if (c->minor == minor) { - new_fops = fops_get(c->fops); + new_fops = fops_get(c->fops); break; } } - + if (!new_fops) { mutex_unlock(&misc_mtx); request_module("char-major-%d-%d", MISC_MAJOR, minor); @@ -167,7 +167,7 @@ static const struct file_operations misc_fops = { /** * misc_register - register a miscellaneous device * @misc: device structure - * + * * Register a miscellaneous device with the kernel. If the minor * number is set to %MISC_DYNAMIC_MINOR a minor number is assigned * and placed in the minor field of the structure. For other cases @@ -181,17 +181,18 @@ static const struct file_operations misc_fops = { * A zero is returned on success and a negative errno code for * failure. */ - + int misc_register(struct miscdevice * misc) { dev_t dev; int err = 0; + bool is_dynamic = (misc->minor == MISC_DYNAMIC_MINOR); INIT_LIST_HEAD(&misc->list); mutex_lock(&misc_mtx); - if (misc->minor == MISC_DYNAMIC_MINOR) { + if (is_dynamic) { int i = find_first_zero_bit(misc_minors, DYNAMIC_MINORS); if (i >= DYNAMIC_MINORS) { err = -EBUSY; @@ -216,9 +217,13 @@ int misc_register(struct miscdevice * misc) device_create_with_groups(misc_class, misc->parent, dev, misc, misc->groups, "%s", misc->name); if (IS_ERR(misc->this_device)) { - int i = DYNAMIC_MINORS - misc->minor - 1; - if (i < DYNAMIC_MINORS && i >= 0) - clear_bit(i, misc_minors); + if (is_dynamic) { + int i = DYNAMIC_MINORS - misc->minor - 1; + + if (i < DYNAMIC_MINORS && i >= 0) + clear_bit(i, misc_minors); + misc->minor = MISC_DYNAMIC_MINOR; + } err = PTR_ERR(misc->this_device); goto out; } @@ -238,17 +243,15 @@ int misc_register(struct miscdevice * misc) * @misc: device to unregister * * Unregister a miscellaneous device that was previously - * successfully registered with misc_register(). Success - * is indicated by a zero return, a negative errno code - * indicates an error. + * successfully registered with misc_register(). */ -int misc_deregister(struct miscdevice *misc) +void misc_deregister(struct miscdevice *misc) { int i = DYNAMIC_MINORS - misc->minor - 1; if (WARN_ON(list_empty(&misc->list))) - return -EINVAL; + return; mutex_lock(&misc_mtx); list_del(&misc->list); @@ -256,7 +259,6 @@ int misc_deregister(struct miscdevice *misc) if (i < DYNAMIC_MINORS && i >= 0) clear_bit(i, misc_minors); mutex_unlock(&misc_mtx); - return 0; } EXPORT_SYMBOL(misc_register); @@ -276,10 +278,9 @@ static char *misc_devnode(struct device *dev, umode_t *mode) static int __init misc_init(void) { int err; + struct proc_dir_entry *ret; -#ifdef CONFIG_PROC_FS - proc_create("misc", 0, NULL, &misc_proc_fops); -#endif + ret = proc_create("misc", 0, NULL, &misc_proc_fops); misc_class = class_create(THIS_MODULE, "misc"); err = PTR_ERR(misc_class); if (IS_ERR(misc_class)) @@ -295,7 +296,8 @@ fail_printk: printk("unable to get major %d for misc devices\n", MISC_MAJOR); class_destroy(misc_class); fail_remove: - remove_proc_entry("misc", NULL); + if (ret) + remove_proc_entry("misc", NULL); return err; } subsys_initcall(misc_init);