From ae87221d3ce49d9de1e43756da834fd0bf05a2ad Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Fri, 24 Aug 2007 16:11:54 -0700 Subject: sysfs: crash debugging Print the name of the last-accessed sysfs file when we oops, to help track down oopses which occur in sysfs store/read handlers. Because these oopses tend to not leave any trace of the offending code in the stack traces. Cc: Kay Sievers Cc: Mathieu Desnoyers Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- include/linux/sysfs.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 37fa24152bd8..8ec406afb3eb 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -119,6 +119,8 @@ void sysfs_remove_file_from_group(struct kobject *kobj, void sysfs_notify(struct kobject *kobj, char *dir, char *attr); +void sysfs_printk_last_file(void); + extern int __must_check sysfs_init(void); #else /* CONFIG_SYSFS */ @@ -231,6 +233,10 @@ static inline int __must_check sysfs_init(void) return 0; } +static inline void sysfs_printk_last_file(void) +{ +} + #endif /* CONFIG_SYSFS */ #endif /* _SYSFS_H_ */ -- cgit v1.2.3-59-g8ed1b From 7fb6b5d51daf3613045258ee8add07022d8c39d3 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 21 Jul 2008 20:03:34 -0700 Subject: device create: remove device_create_drvdata Now that the tree is cleaned up, device_create_drvdata can be safely removed. Signed-off-by: Greg Kroah-Hartman --- include/linux/device.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/device.h b/include/linux/device.h index 246937c9cbc7..60f6456691a6 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -502,7 +502,6 @@ extern struct device *device_create(struct class *cls, struct device *parent, dev_t devt, void *drvdata, const char *fmt, ...) __attribute__((format(printf, 5, 6))); -#define device_create_drvdata device_create extern void device_destroy(struct class *cls, dev_t devt); /* -- cgit v1.2.3-59-g8ed1b From 346e15beb5343c2eb8216d820f2ed8f150822b08 Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Tue, 12 Aug 2008 16:46:19 -0400 Subject: driver core: basic infrastructure for per-module dynamic debug messages Base infrastructure to enable per-module debug messages. I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes control of debugging statements on a per-module basis in one /proc file, currently, /dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG, is not set, debugging statements can still be enabled as before, often by defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set. The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls can be dynamically enabled/disabled on a per-module basis. Future plans include extending this functionality to subsystems, that define their own debug levels and flags. Usage: Dynamic debugging is controlled by the debugfs file, /dynamic_printk/modules. This file contains a list of the modules that can be enabled. The format of the file is as follows: . . . : Name of the module in which the debug call resides : whether the messages are enabled or not For example: snd_hda_intel enabled=0 fixup enabled=1 driver enabled=0 Enable a module: $echo "set enabled=1 " > dynamic_printk/modules Disable a module: $echo "set enabled=0 " > dynamic_printk/modules Enable all modules: $echo "set enabled=1 all" > dynamic_printk/modules Disable all modules: $echo "set enabled=0 all" > dynamic_printk/modules Finally, passing "dynamic_printk" at the command line enables debugging for all modules. This mode can be turned off via the above disable command. [gkh: minor cleanups and tweaks to make the build work quietly] Signed-off-by: Jason Baron Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 5 + include/asm-generic/vmlinux.lds.h | 10 +- include/linux/device.h | 6 +- include/linux/dynamic_printk.h | 93 ++++++++ include/linux/kernel.h | 7 +- include/linux/module.h | 1 - kernel/module.c | 31 +++ lib/Kconfig.debug | 55 +++++ lib/Makefile | 2 + lib/dynamic_printk.c | 418 ++++++++++++++++++++++++++++++++++++ net/netfilter/nf_conntrack_pptp.c | 2 +- scripts/Makefile.lib | 11 +- scripts/basic/Makefile | 2 +- scripts/basic/hash.c | 64 ++++++ 14 files changed, 700 insertions(+), 7 deletions(-) create mode 100644 include/linux/dynamic_printk.h create mode 100644 lib/dynamic_printk.c create mode 100644 scripts/basic/hash.c (limited to 'include/linux') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 2443f5bb4364..b429c84ceef2 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1713,6 +1713,11 @@ and is between 256 and 4096 characters. It is defined in the file autoconfiguration. Ranges are in pairs (memory base and size). + dynamic_printk + Enables pr_debug()/dev_dbg() calls if + CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. These can also + be switched on/off via /dynamic_printk/modules + print-fatal-signals= [KNL] debug: print fatal signals print-fatal-signals=1: print segfault info to diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 7440a0dceddb..74c5faf26c05 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -268,7 +268,15 @@ CPU_DISCARD(init.data) \ CPU_DISCARD(init.rodata) \ MEM_DISCARD(init.data) \ - MEM_DISCARD(init.rodata) + MEM_DISCARD(init.rodata) \ + /* implement dynamic printk debug */ \ + VMLINUX_SYMBOL(__start___verbose_strings) = .; \ + *(__verbose_strings) \ + VMLINUX_SYMBOL(__stop___verbose_strings) = .; \ + . = ALIGN(8); \ + VMLINUX_SYMBOL(__start___verbose) = .; \ + *(__verbose) \ + VMLINUX_SYMBOL(__stop___verbose) = .; #define INIT_TEXT \ *(.init.text) \ diff --git a/include/linux/device.h b/include/linux/device.h index 60f6456691a6..fb034461b395 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -550,7 +550,11 @@ extern const char *dev_driver_string(const struct device *dev); #define dev_info(dev, format, arg...) \ dev_printk(KERN_INFO , dev , format , ## arg) -#ifdef DEBUG +#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG) +#define dev_dbg(dev, format, ...) do { \ + dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \ + } while (0) +#elif defined(DEBUG) #define dev_dbg(dev, format, arg...) \ dev_printk(KERN_DEBUG , dev , format , ## arg) #else diff --git a/include/linux/dynamic_printk.h b/include/linux/dynamic_printk.h new file mode 100644 index 000000000000..2d528d009074 --- /dev/null +++ b/include/linux/dynamic_printk.h @@ -0,0 +1,93 @@ +#ifndef _DYNAMIC_PRINTK_H +#define _DYNAMIC_PRINTK_H + +#define DYNAMIC_DEBUG_HASH_BITS 6 +#define DEBUG_HASH_TABLE_SIZE (1 << DYNAMIC_DEBUG_HASH_BITS) + +#define TYPE_BOOLEAN 1 + +#define DYNAMIC_ENABLED_ALL 0 +#define DYNAMIC_ENABLED_NONE 1 +#define DYNAMIC_ENABLED_SOME 2 + +extern int dynamic_enabled; + +/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which + * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They + * use independent hash functions, to reduce the chance of false positives. + */ +extern long long dynamic_printk_enabled; +extern long long dynamic_printk_enabled2; + +struct mod_debug { + char *modname; + char *logical_modname; + char *flag_names; + int type; + int hash; + int hash2; +} __attribute__((aligned(8))); + +int register_dynamic_debug_module(char *mod_name, int type, char *share_name, + char *flags, int hash, int hash2); + +#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG) +extern int unregister_dynamic_debug_module(char *mod_name); +extern int __dynamic_dbg_enabled_helper(char *modname, int type, + int value, int hash); + +#define __dynamic_dbg_enabled(module, type, value, level, hash) ({ \ + int __ret = 0; \ + if (unlikely((dynamic_printk_enabled & (1LL << DEBUG_HASH)) && \ + (dynamic_printk_enabled2 & (1LL << DEBUG_HASH2)))) \ + __ret = __dynamic_dbg_enabled_helper(module, type, \ + value, hash);\ + __ret; }) + +#define dynamic_pr_debug(fmt, ...) do { \ + static char mod_name[] \ + __attribute__((section("__verbose_strings"))) \ + = KBUILD_MODNAME; \ + static struct mod_debug descriptor \ + __used \ + __attribute__((section("__verbose"), aligned(8))) = \ + { mod_name, mod_name, NULL, TYPE_BOOLEAN, DEBUG_HASH, DEBUG_HASH2 };\ + if (__dynamic_dbg_enabled(KBUILD_MODNAME, TYPE_BOOLEAN, \ + 0, 0, DEBUG_HASH)) \ + printk(KERN_DEBUG KBUILD_MODNAME ":" fmt, \ + ##__VA_ARGS__); \ + } while (0) + +#define dynamic_dev_dbg(dev, format, ...) do { \ + static char mod_name[] \ + __attribute__((section("__verbose_strings"))) \ + = KBUILD_MODNAME; \ + static struct mod_debug descriptor \ + __used \ + __attribute__((section("__verbose"), aligned(8))) = \ + { mod_name, mod_name, NULL, TYPE_BOOLEAN, DEBUG_HASH, DEBUG_HASH2 };\ + if (__dynamic_dbg_enabled(KBUILD_MODNAME, TYPE_BOOLEAN, \ + 0, 0, DEBUG_HASH)) \ + dev_printk(KERN_DEBUG, dev, \ + KBUILD_MODNAME ": " format, \ + ##__VA_ARGS__); \ + } while (0) + +#else + +static inline int unregister_dynamic_debug_module(const char *mod_name) +{ + return 0; +} +static inline int __dynamic_dbg_enabled_helper(char *modname, int type, + int value, int hash) +{ + return 0; +} + +#define __dynamic_dbg_enabled(module, type, value, level, hash) ({ 0; }) +#define dynamic_pr_debug(fmt, ...) do { } while (0) +#define dynamic_dev_dbg(dev, format, ...) do { } while (0) +#endif + +#endif diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 75d81f157d2e..ededb6e83b41 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -303,8 +304,12 @@ static inline char *pack_hex_byte(char *buf, u8 byte) #define pr_info(fmt, arg...) \ printk(KERN_INFO fmt, ##arg) -#ifdef DEBUG /* If you are writing a driver, please use dev_dbg instead */ +#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG) +#define pr_debug(fmt, ...) do { \ + dynamic_pr_debug(fmt, ##__VA_ARGS__); \ + } while (0) +#elif defined(DEBUG) #define pr_debug(fmt, arg...) \ printk(KERN_DEBUG fmt, ##arg) #else diff --git a/include/linux/module.h b/include/linux/module.h index 68e09557c951..a41555cbe00a 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -345,7 +345,6 @@ struct module /* Reference counts */ struct module_ref ref[NR_CPUS]; #endif - }; #ifndef MODULE_ARCH_INIT #define MODULE_ARCH_INIT {} diff --git a/kernel/module.c b/kernel/module.c index d5fcd24e5aff..c52700667292 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -784,6 +784,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) mutex_lock(&module_mutex); /* Store the name of the last unloaded module for diagnostic purposes */ strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); + unregister_dynamic_debug_module(mod->name); free_module(mod); out: @@ -1783,6 +1784,33 @@ static inline void add_kallsyms(struct module *mod, } #endif /* CONFIG_KALLSYMS */ +#ifdef CONFIG_DYNAMIC_PRINTK_DEBUG +static void dynamic_printk_setup(Elf_Shdr *sechdrs, unsigned int verboseindex) +{ + struct mod_debug *debug_info; + unsigned long pos, end; + unsigned int num_verbose; + + pos = sechdrs[verboseindex].sh_addr; + num_verbose = sechdrs[verboseindex].sh_size / + sizeof(struct mod_debug); + end = pos + (num_verbose * sizeof(struct mod_debug)); + + for (; pos < end; pos += sizeof(struct mod_debug)) { + debug_info = (struct mod_debug *)pos; + register_dynamic_debug_module(debug_info->modname, + debug_info->type, debug_info->logical_modname, + debug_info->flag_names, debug_info->hash, + debug_info->hash2); + } +} +#else +static inline void dynamic_printk_setup(Elf_Shdr *sechdrs, + unsigned int verboseindex) +{ +} +#endif /* CONFIG_DYNAMIC_PRINTK_DEBUG */ + static void *module_alloc_update_bounds(unsigned long size) { void *ret = module_alloc(size); @@ -1831,6 +1859,7 @@ static noinline struct module *load_module(void __user *umod, #endif unsigned int markersindex; unsigned int markersstringsindex; + unsigned int verboseindex; struct module *mod; long err = 0; void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ @@ -2117,6 +2146,7 @@ static noinline struct module *load_module(void __user *umod, markersindex = find_sec(hdr, sechdrs, secstrings, "__markers"); markersstringsindex = find_sec(hdr, sechdrs, secstrings, "__markers_strings"); + verboseindex = find_sec(hdr, sechdrs, secstrings, "__verbose"); /* Now do relocations. */ for (i = 1; i < hdr->e_shnum; i++) { @@ -2167,6 +2197,7 @@ static noinline struct module *load_module(void __user *umod, marker_update_probe_range(mod->markers, mod->markers + mod->num_markers); #endif + dynamic_printk_setup(sechdrs, verboseindex); err = module_finalize(hdr, sechdrs, mod); if (err < 0) goto cleanup; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index aa81d2848448..31d784dd80d0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -807,6 +807,61 @@ menuconfig BUILD_DOCSRC Say N if you are unsure. +config DYNAMIC_PRINTK_DEBUG + bool "Enable dynamic printk() call support" + default n + depends on PRINTK + select PRINTK_DEBUG + help + + Compiles debug level messages into the kernel, which would not + otherwise be available at runtime. These messages can then be + enabled/disabled on a per module basis. This mechanism implicitly + enables all pr_debug() and dev_dbg() calls. The impact of this + compile option is a larger kernel text size of about 2%. + + Usage: + + Dynamic debugging is controlled by the debugfs file, + dynamic_printk/modules. This file contains a list of the modules that + can be enabled. The format of the file is the module name, followed + by a set of flags that can be enabled. The first flag is always the + 'enabled' flag. For example: + + + . + . + . + + : Name of the module in which the debug call resides + : whether the messages are enabled or not + + From a live system: + + snd_hda_intel enabled=0 + fixup enabled=0 + driver enabled=0 + + Enable a module: + + $echo "set enabled=1 " > dynamic_printk/modules + + Disable a module: + + $echo "set enabled=0 " > dynamic_printk/modules + + Enable all modules: + + $echo "set enabled=1 all" > dynamic_printk/modules + + Disable all modules: + + $echo "set enabled=0 all" > dynamic_printk/modules + + Finally, passing "dynamic_printk" at the command line enables + debugging for all modules. This mode can be turned off via the above + disable command. + source "samples/Kconfig" source "lib/Kconfig.kgdb" diff --git a/lib/Makefile b/lib/Makefile index 44001af76a7d..16feaab057b2 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -81,6 +81,8 @@ obj-$(CONFIG_HAVE_LMB) += lmb.o obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o +obj-$(CONFIG_DYNAMIC_PRINTK_DEBUG) += dynamic_printk.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/dynamic_printk.c b/lib/dynamic_printk.c new file mode 100644 index 000000000000..d640f87bdc9e --- /dev/null +++ b/lib/dynamic_printk.c @@ -0,0 +1,418 @@ +/* + * lib/dynamic_printk.c + * + * make pr_debug()/dev_dbg() calls runtime configurable based upon their + * their source module. + * + * Copyright (C) 2008 Red Hat, Inc., Jason Baron + */ + +#include +#include +#include +#include +#include +#include + +extern struct mod_debug __start___verbose[]; +extern struct mod_debug __stop___verbose[]; + +struct debug_name { + struct hlist_node hlist; + struct hlist_node hlist2; + int hash1; + int hash2; + char *name; + int enable; + int type; +}; + +static int nr_entries; +static int num_enabled; +int dynamic_enabled = DYNAMIC_ENABLED_NONE; +static struct hlist_head module_table[DEBUG_HASH_TABLE_SIZE] = + { [0 ... DEBUG_HASH_TABLE_SIZE-1] = HLIST_HEAD_INIT }; +static struct hlist_head module_table2[DEBUG_HASH_TABLE_SIZE] = + { [0 ... DEBUG_HASH_TABLE_SIZE-1] = HLIST_HEAD_INIT }; +static DECLARE_MUTEX(debug_list_mutex); + +/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which + * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They + * use independent hash functions, to reduce the chance of false positives. + */ +long long dynamic_printk_enabled; +EXPORT_SYMBOL_GPL(dynamic_printk_enabled); +long long dynamic_printk_enabled2; +EXPORT_SYMBOL_GPL(dynamic_printk_enabled2); + +/* returns the debug module pointer. */ +static struct debug_name *find_debug_module(char *module_name) +{ + int i; + struct hlist_head *head; + struct hlist_node *node; + struct debug_name *element; + + element = NULL; + for (i = 0; i < DEBUG_HASH_TABLE_SIZE; i++) { + head = &module_table[i]; + hlist_for_each_entry_rcu(element, node, head, hlist) + if (!strcmp(element->name, module_name)) + return element; + } + return NULL; +} + +/* returns the debug module pointer. */ +static struct debug_name *find_debug_module_hash(char *module_name, int hash) +{ + struct hlist_head *head; + struct hlist_node *node; + struct debug_name *element; + + element = NULL; + head = &module_table[hash]; + hlist_for_each_entry_rcu(element, node, head, hlist) + if (!strcmp(element->name, module_name)) + return element; + return NULL; +} + +/* caller must hold mutex*/ +static int __add_debug_module(char *mod_name, int hash, int hash2) +{ + struct debug_name *new; + char *module_name; + int ret = 0; + + if (find_debug_module(mod_name)) { + ret = -EINVAL; + goto out; + } + module_name = kmalloc(strlen(mod_name) + 1, GFP_KERNEL); + if (!module_name) { + ret = -ENOMEM; + goto out; + } + module_name = strcpy(module_name, mod_name); + module_name[strlen(mod_name)] = '\0'; + new = kzalloc(sizeof(struct debug_name), GFP_KERNEL); + if (!new) { + kfree(module_name); + ret = -ENOMEM; + goto out; + } + INIT_HLIST_NODE(&new->hlist); + INIT_HLIST_NODE(&new->hlist2); + new->name = module_name; + new->hash1 = hash; + new->hash2 = hash2; + hlist_add_head_rcu(&new->hlist, &module_table[hash]); + hlist_add_head_rcu(&new->hlist2, &module_table2[hash2]); + nr_entries++; +out: + return ret; +} + +int unregister_dynamic_debug_module(char *mod_name) +{ + struct debug_name *element; + int ret = 0; + + down(&debug_list_mutex); + element = find_debug_module(mod_name); + if (!element) { + ret = -EINVAL; + goto out; + } + hlist_del_rcu(&element->hlist); + hlist_del_rcu(&element->hlist2); + synchronize_rcu(); + kfree(element->name); + if (element->enable) + num_enabled--; + kfree(element); + nr_entries--; +out: + up(&debug_list_mutex); + return 0; +} +EXPORT_SYMBOL_GPL(unregister_dynamic_debug_module); + +int register_dynamic_debug_module(char *mod_name, int type, char *share_name, + char *flags, int hash, int hash2) +{ + struct debug_name *elem; + int ret = 0; + + down(&debug_list_mutex); + elem = find_debug_module(mod_name); + if (!elem) { + if (__add_debug_module(mod_name, hash, hash2)) + goto out; + elem = find_debug_module(mod_name); + if (dynamic_enabled == DYNAMIC_ENABLED_ALL && + !strcmp(mod_name, share_name)) { + elem->enable = true; + num_enabled++; + } + } + elem->type |= type; +out: + up(&debug_list_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(register_dynamic_debug_module); + +int __dynamic_dbg_enabled_helper(char *mod_name, int type, int value, int hash) +{ + struct debug_name *elem; + int ret = 0; + + if (dynamic_enabled == DYNAMIC_ENABLED_ALL) + return 1; + rcu_read_lock(); + elem = find_debug_module_hash(mod_name, hash); + if (elem && elem->enable) + ret = 1; + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(__dynamic_dbg_enabled_helper); + +static void set_all(bool enable) +{ + struct debug_name *e; + struct hlist_node *node; + int i; + long long enable_mask; + + for (i = 0; i < DEBUG_HASH_TABLE_SIZE; i++) { + if (module_table[i].first != NULL) { + hlist_for_each_entry(e, node, &module_table[i], hlist) { + e->enable = enable; + } + } + } + if (enable) + enable_mask = ULLONG_MAX; + else + enable_mask = 0; + dynamic_printk_enabled = enable_mask; + dynamic_printk_enabled2 = enable_mask; +} + +static int disabled_hash(int i, bool first_table) +{ + struct debug_name *e; + struct hlist_node *node; + + if (first_table) { + hlist_for_each_entry(e, node, &module_table[i], hlist) { + if (e->enable) + return 0; + } + } else { + hlist_for_each_entry(e, node, &module_table2[i], hlist2) { + if (e->enable) + return 0; + } + } + return 1; +} + +static ssize_t pr_debug_write(struct file *file, const char __user *buf, + size_t length, loff_t *ppos) +{ + char *buffer, *s, *value_str, *setting_str; + int err, value; + struct debug_name *elem = NULL; + int all = 0; + + if (length > PAGE_SIZE || length < 0) + return -EINVAL; + + buffer = (char *)__get_free_page(GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + err = -EFAULT; + if (copy_from_user(buffer, buf, length)) + goto out; + + err = -EINVAL; + if (length < PAGE_SIZE) + buffer[length] = '\0'; + else if (buffer[PAGE_SIZE-1]) + goto out; + + err = -EINVAL; + down(&debug_list_mutex); + + if (strncmp("set", buffer, 3)) + goto out_up; + s = buffer + 3; + setting_str = strsep(&s, "="); + if (s == NULL) + goto out_up; + setting_str = strstrip(setting_str); + value_str = strsep(&s, " "); + if (s == NULL) + goto out_up; + s = strstrip(s); + if (!strncmp(s, "all", 3)) + all = 1; + else + elem = find_debug_module(s); + if (!strncmp(setting_str, "enable", 6)) { + value = !!simple_strtol(value_str, NULL, 10); + if (all) { + if (value) { + set_all(true); + num_enabled = nr_entries; + dynamic_enabled = DYNAMIC_ENABLED_ALL; + } else { + set_all(false); + num_enabled = 0; + dynamic_enabled = DYNAMIC_ENABLED_NONE; + } + err = 0; + } else { + if (elem) { + if (value && (elem->enable == 0)) { + dynamic_printk_enabled |= + (1LL << elem->hash1); + dynamic_printk_enabled2 |= + (1LL << elem->hash2); + elem->enable = 1; + num_enabled++; + dynamic_enabled = DYNAMIC_ENABLED_SOME; + err = 0; + printk(KERN_DEBUG + "debugging enabled for module %s", + elem->name); + } else if (!value && (elem->enable == 1)) { + elem->enable = 0; + num_enabled--; + if (disabled_hash(elem->hash1, true)) + dynamic_printk_enabled &= + ~(1LL << elem->hash1); + if (disabled_hash(elem->hash2, false)) + dynamic_printk_enabled2 &= + ~(1LL << elem->hash2); + if (num_enabled) + dynamic_enabled = + DYNAMIC_ENABLED_SOME; + else + dynamic_enabled = + DYNAMIC_ENABLED_NONE; + err = 0; + printk(KERN_DEBUG + "debugging disabled for module " + "%s", elem->name); + } + } + } + } + if (!err) + err = length; +out_up: + up(&debug_list_mutex); +out: + free_page((unsigned long)buffer); + return err; +} + +static void *pr_debug_seq_start(struct seq_file *f, loff_t *pos) +{ + return (*pos < DEBUG_HASH_TABLE_SIZE) ? pos : NULL; +} + +static void *pr_debug_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + (*pos)++; + if (*pos >= DEBUG_HASH_TABLE_SIZE) + return NULL; + return pos; +} + +static void pr_debug_seq_stop(struct seq_file *s, void *v) +{ + /* Nothing to do */ +} + +static int pr_debug_seq_show(struct seq_file *s, void *v) +{ + struct hlist_head *head; + struct hlist_node *node; + struct debug_name *elem; + unsigned int i = *(loff_t *) v; + + rcu_read_lock(); + head = &module_table[i]; + hlist_for_each_entry_rcu(elem, node, head, hlist) { + seq_printf(s, "%s enabled=%d", elem->name, elem->enable); + seq_printf(s, "\n"); + } + rcu_read_unlock(); + return 0; +} + +static struct seq_operations pr_debug_seq_ops = { + .start = pr_debug_seq_start, + .next = pr_debug_seq_next, + .stop = pr_debug_seq_stop, + .show = pr_debug_seq_show +}; + +static int pr_debug_open(struct inode *inode, struct file *filp) +{ + return seq_open(filp, &pr_debug_seq_ops); +} + +static const struct file_operations pr_debug_operations = { + .open = pr_debug_open, + .read = seq_read, + .write = pr_debug_write, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init dynamic_printk_init(void) +{ + struct dentry *dir, *file; + struct mod_debug *iter; + unsigned long value; + + dir = debugfs_create_dir("dynamic_printk", NULL); + if (!dir) + return -ENOMEM; + file = debugfs_create_file("modules", 0644, dir, NULL, + &pr_debug_operations); + if (!file) { + debugfs_remove(dir); + return -ENOMEM; + } + for (value = (unsigned long)__start___verbose; + value < (unsigned long)__stop___verbose; + value += sizeof(struct mod_debug)) { + iter = (struct mod_debug *)value; + register_dynamic_debug_module(iter->modname, + iter->type, + iter->logical_modname, + iter->flag_names, iter->hash, iter->hash2); + } + return 0; +} +module_init(dynamic_printk_init); +/* may want to move this earlier so we can get traces as early as possible */ + +static int __init dynamic_printk_setup(char *str) +{ + if (str) + return -ENOENT; + set_all(true); + return 0; +} +/* Use early_param(), so we can get debug output as early as possible */ +early_param("dynamic_printk", dynamic_printk_setup); diff --git a/net/netfilter/nf_conntrack_pptp.c b/net/netfilter/nf_conntrack_pptp.c index 373e51e91ce5..1bc3001d1827 100644 --- a/net/netfilter/nf_conntrack_pptp.c +++ b/net/netfilter/nf_conntrack_pptp.c @@ -65,7 +65,7 @@ void struct nf_conntrack_expect *exp) __read_mostly; EXPORT_SYMBOL_GPL(nf_nat_pptp_hook_expectfn); -#ifdef DEBUG +#if defined(DEBUG) || defined(CONFIG_DYNAMIC_PRINTK_DEBUG) /* PptpControlMessageType names */ const char *const pptp_msg_name[] = { "UNKNOWN_MESSAGE", diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index ea48b82a3707..b4ca38a21158 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -96,6 +96,14 @@ basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))" modname_flags = $(if $(filter 1,$(words $(modname))),\ -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))") +#hash values +ifdef CONFIG_DYNAMIC_PRINTK_DEBUG +debug_flags = -D"DEBUG_HASH=$(shell ./scripts/basic/hash djb2 $(@D)$(modname))"\ + -D"DEBUG_HASH2=$(shell ./scripts/basic/hash r5 $(@D)$(modname))" +else +debug_flags = +endif + orig_c_flags = $(KBUILD_CFLAGS) $(ccflags-y) $(CFLAGS_$(basetarget).o) _c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) _a_flags = $(KBUILD_AFLAGS) $(asflags-y) $(AFLAGS_$(basetarget).o) @@ -121,7 +129,8 @@ endif c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \ $(__c_flags) $(modkern_cflags) \ - -D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags) + -D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags) \ + $(debug_flags) a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \ $(__a_flags) $(modkern_aflags) diff --git a/scripts/basic/Makefile b/scripts/basic/Makefile index 4c324a1f1e0e..09559951df12 100644 --- a/scripts/basic/Makefile +++ b/scripts/basic/Makefile @@ -9,7 +9,7 @@ # fixdep: Used to generate dependency information during build process # docproc: Used in Documentation/DocBook -hostprogs-y := fixdep docproc +hostprogs-y := fixdep docproc hash always := $(hostprogs-y) # fixdep is needed to compile other host programs diff --git a/scripts/basic/hash.c b/scripts/basic/hash.c new file mode 100644 index 000000000000..3299ad7fc8c0 --- /dev/null +++ b/scripts/basic/hash.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2008 Red Hat, Inc., Jason Baron + * + */ + +#include +#include +#include + +#define DYNAMIC_DEBUG_HASH_BITS 6 + +static const char *program; + +static void usage(void) +{ + printf("Usage: %s \n", program); + exit(1); +} + +/* djb2 hashing algorithm by Dan Bernstein. From: + * http://www.cse.yorku.ca/~oz/hash.html + */ + +unsigned int djb2_hash(char *str) +{ + unsigned long hash = 5381; + int c; + + c = *str; + while (c) { + hash = ((hash << 5) + hash) + c; + c = *++str; + } + return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1)); +} + +unsigned int r5_hash(char *str) +{ + unsigned long hash = 0; + int c; + + c = *str; + while (c) { + hash = (hash + (c << 4) + (c >> 4)) * 11; + c = *++str; + } + return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1)); +} + +int main(int argc, char *argv[]) +{ + program = argv[0]; + + if (argc != 3) + usage(); + if (!strcmp(argv[1], "djb2")) + printf("%d\n", djb2_hash(argv[2])); + else if (!strcmp(argv[1], "r5")) + printf("%d\n", r5_hash(argv[2])); + else + usage(); + exit(0); +} + -- cgit v1.2.3-59-g8ed1b From f1282c844e86db5a041afa41335b5f9eea6cec0c Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Wed, 16 Jul 2008 08:58:04 +1000 Subject: sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown Acked-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 1 + fs/sysfs/file.c | 31 ++++++++++++++++++------------- fs/sysfs/mount.c | 15 +++++++++++++++ fs/sysfs/sysfs.h | 6 ++++-- include/linux/sysfs.h | 27 ++++++++++++++++++++++++--- 5 files changed, 62 insertions(+), 18 deletions(-) (limited to 'include/linux') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index aedaeba82ae5..53bc7fc31af3 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -636,6 +636,7 @@ struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, return sd; } +EXPORT_SYMBOL_GPL(sysfs_get_dirent); static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, const char *name, struct sysfs_dirent **p_sd) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index ce8339c70a4b..d0d79e6b6d11 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -453,6 +453,22 @@ static unsigned int sysfs_poll(struct file *filp, poll_table *wait) return POLLERR|POLLPRI; } +void sysfs_notify_dirent(struct sysfs_dirent *sd) +{ + struct sysfs_open_dirent *od; + + spin_lock(&sysfs_open_dirent_lock); + + od = sd->s_attr.open; + if (od) { + atomic_inc(&od->event); + wake_up_interruptible(&od->poll); + } + + spin_unlock(&sysfs_open_dirent_lock); +} +EXPORT_SYMBOL_GPL(sysfs_notify_dirent); + void sysfs_notify(struct kobject *k, char *dir, char *attr) { struct sysfs_dirent *sd = k->sd; @@ -463,19 +479,8 @@ void sysfs_notify(struct kobject *k, char *dir, char *attr) sd = sysfs_find_dirent(sd, dir); if (sd && attr) sd = sysfs_find_dirent(sd, attr); - if (sd) { - struct sysfs_open_dirent *od; - - spin_lock(&sysfs_open_dirent_lock); - - od = sd->s_attr.open; - if (od) { - atomic_inc(&od->event); - wake_up_interruptible(&od->poll); - } - - spin_unlock(&sysfs_open_dirent_lock); - } + if (sd) + sysfs_notify_dirent(sd); mutex_unlock(&sysfs_mutex); } diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 14f0023984d7..ab343e371d64 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "sysfs.h" @@ -115,3 +116,17 @@ out_err: sysfs_dir_cachep = NULL; goto out; } + +#undef sysfs_get +struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd) +{ + return __sysfs_get(sd); +} +EXPORT_SYMBOL_GPL(sysfs_get); + +#undef sysfs_put +void sysfs_put(struct sysfs_dirent *sd) +{ + __sysfs_put(sd); +} +EXPORT_SYMBOL_GPL(sysfs_put); diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index a5db496f71c7..93c6d6b27c4d 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -124,7 +124,7 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name, struct sysfs_dirent **p_sd); void sysfs_remove_subdir(struct sysfs_dirent *sd); -static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd) +static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd) { if (sd) { WARN_ON(!atomic_read(&sd->s_count)); @@ -132,12 +132,14 @@ static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd) } return sd; } +#define sysfs_get(sd) __sysfs_get(sd) -static inline void sysfs_put(struct sysfs_dirent *sd) +static inline void __sysfs_put(struct sysfs_dirent *sd) { if (sd && atomic_dec_and_test(&sd->s_count)) release_sysfs_dirent(sd); } +#define sysfs_put(sd) __sysfs_put(sd) /* * inode.c diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 8ec406afb3eb..d8e0230f1e68 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -78,6 +78,8 @@ struct sysfs_ops { ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t); }; +struct sysfs_dirent; + #ifdef CONFIG_SYSFS int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *), @@ -118,10 +120,13 @@ void sysfs_remove_file_from_group(struct kobject *kobj, const struct attribute *attr, const char *group); void sysfs_notify(struct kobject *kobj, char *dir, char *attr); - +void sysfs_notify_dirent(struct sysfs_dirent *sd); +struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, + const unsigned char *name); +struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd); +void sysfs_put(struct sysfs_dirent *sd); void sysfs_printk_last_file(void); - -extern int __must_check sysfs_init(void); +int __must_check sysfs_init(void); #else /* CONFIG_SYSFS */ @@ -227,6 +232,22 @@ static inline void sysfs_remove_file_from_group(struct kobject *kobj, static inline void sysfs_notify(struct kobject *kobj, char *dir, char *attr) { } +static inline void sysfs_notify_dirent(struct sysfs_dirent *sd) +{ +} +static inline +struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, + const unsigned char *name) +{ + return NULL; +} +static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd) +{ + return NULL; +} +static inline void sysfs_put(struct sysfs_dirent *sd) +{ +} static inline int __must_check sysfs_init(void) { -- cgit v1.2.3-59-g8ed1b From e61396627f91abb855ddd8925be9172fb5871944 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sat, 20 Sep 2008 19:08:39 -0700 Subject: debug: Introduce a dev_WARN() function in the line of dev_printk(), this patch introduces a dev_WARN() function, that takes a struct device and then a printk format/args set of arguments. Unlike dev_printk(), the effect is that of WARN() in that a full warning message (including filename/line, module list, versions and a backtrace) is printed in addition to the device name and the arguments. Signed-off-by: Arjan van de Ven Signed-off-by: Greg Kroah-Hartman --- include/linux/device.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux') diff --git a/include/linux/device.h b/include/linux/device.h index fb034461b395..ec90e79f6a00 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -570,6 +570,14 @@ extern const char *dev_driver_string(const struct device *dev); ({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; }) #endif +/* + * dev_WARN() acts like dev_printk(), but with the key difference + * of using a WARN/WARN_ON to get the message out, including the + * file/line information and a backtrace. + */ +#define dev_WARN(dev, format, arg...) \ + WARN(1, "Device: %s\n" format, dev_driver_string(dev), ## arg); + /* Create alias, so I can be autoloaded. */ #define MODULE_ALIAS_CHARDEV(major,minor) \ MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) -- cgit v1.2.3-59-g8ed1b From d8bf254089a6c31d7d01a4d1d2f1861662900855 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Mon, 22 Sep 2008 14:41:40 -0700 Subject: platform: add new device registration helper Add a helper that registers simple platform_device w/o resources but with parent and device data. This is usefull to cleanup platform code from code that registers such simple devices as leds-gpio, generic-bl, etc. Signed-off-by: Dmitry Baryshkov Cc: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/base/platform.c | 47 +++++++++++++++++++++++++++++++++++++++++ include/linux/platform_device.h | 2 ++ 2 files changed, 49 insertions(+) (limited to 'include/linux') diff --git a/drivers/base/platform.c b/drivers/base/platform.c index e621dade7eaa..9e60f7c739c6 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -391,6 +391,53 @@ error: } EXPORT_SYMBOL_GPL(platform_device_register_simple); +/** + * platform_device_register_data + * @parent: parent device for the device we're adding + * @name: base name of the device we're adding + * @id: instance id + * @data: platform specific data for this platform device + * @size: size of platform specific data + * + * This function creates a simple platform device that requires minimal + * resource and memory management. Canned release function freeing memory + * allocated for the device allows drivers using such devices to be + * unloaded without waiting for the last reference to the device to be + * dropped. + */ +struct platform_device *platform_device_register_data( + struct device *parent, + const char *name, int id, + const void *data, size_t size) +{ + struct platform_device *pdev; + int retval; + + pdev = platform_device_alloc(name, id); + if (!pdev) { + retval = -ENOMEM; + goto error; + } + + pdev->dev.parent = parent; + + if (size) { + retval = platform_device_add_data(pdev, data, size); + if (retval) + goto error; + } + + retval = platform_device_add(pdev); + if (retval) + goto error; + + return pdev; + +error: + platform_device_put(pdev); + return ERR_PTR(retval); +} + static int platform_drv_probe(struct device *_dev) { struct platform_driver *drv = to_platform_driver(_dev->driver); diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 95ac21ab3a09..4b8cc6a32479 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -37,6 +37,8 @@ extern int platform_add_devices(struct platform_device **, int); extern struct platform_device *platform_device_register_simple(const char *, int id, struct resource *, unsigned int); +extern struct platform_device *platform_device_register_data(struct device *, + const char *, int, const void *, size_t); extern struct platform_device *platform_device_alloc(const char *name, int id); extern int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num); -- cgit v1.2.3-59-g8ed1b From 8c0e3998f5b71e68fe6b6e489a92e052715e563c Mon Sep 17 00:00:00 2001 From: Trent Piepho Date: Thu, 25 Sep 2008 16:45:13 -0700 Subject: sysfs: Make dir and name args to sysfs_notify() const Because they can be, and because code like this produces a warning if they're not: struct device_attribute dev_attr; sysfs_notify(&kobj, NULL, dev_attr.attr.name); Signed-off-by: Trent Piepho CC: Neil Brown Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/file.c | 2 +- include/linux/sysfs.h | 5 +++-- 2 files changed, 4 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index d0d79e6b6d11..1f4a3f877262 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -469,7 +469,7 @@ void sysfs_notify_dirent(struct sysfs_dirent *sd) } EXPORT_SYMBOL_GPL(sysfs_notify_dirent); -void sysfs_notify(struct kobject *k, char *dir, char *attr) +void sysfs_notify(struct kobject *k, const char *dir, const char *attr) { struct sysfs_dirent *sd = k->sd; diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index d8e0230f1e68..b330e289d71f 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -119,7 +119,7 @@ int sysfs_add_file_to_group(struct kobject *kobj, void sysfs_remove_file_from_group(struct kobject *kobj, const struct attribute *attr, const char *group); -void sysfs_notify(struct kobject *kobj, char *dir, char *attr); +void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr); void sysfs_notify_dirent(struct sysfs_dirent *sd); struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, const unsigned char *name); @@ -229,7 +229,8 @@ static inline void sysfs_remove_file_from_group(struct kobject *kobj, { } -static inline void sysfs_notify(struct kobject *kobj, char *dir, char *attr) +static inline void sysfs_notify(struct kobject *kobj, const char *dir, + const char *attr) { } static inline void sysfs_notify_dirent(struct sysfs_dirent *sd) -- cgit v1.2.3-59-g8ed1b From 030c1d2bfcc2187650fb975456ca0b61a5bb77f4 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 8 May 2008 14:41:00 -0700 Subject: kobject: Fix kobject_rename and !CONFIG_SYSFS When looking at kobject_rename I found two bugs with that exist when sysfs support is disabled in the kernel. kobject_rename does not change the name on the kobject when sysfs support is not compiled in. kobject_rename without locking attempts to check the validity of a rename operation, which the kobject layer simply does not have the infrastructure to do. This patch documents the previously unstated requirement of kobject_rename that is the responsibility of the caller to provide mutual exclusion and to be certain that the new_name for the kobject is valid. This patch modifies sysfs_rename_dir in !CONFIG_SYSFS case to call kobject_set_name to actually change the kobject_name. This patch removes the bogus and misleading check in kobject_rename that attempts to see if a rename is valid. The check is bogus because we do not have the proper locking. The check is misleading because it looks like we can and do perform checking at the kobject level that we don't. Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman --- Documentation/kobject.txt | 4 ++++ drivers/base/core.c | 5 +++++ include/linux/sysfs.h | 4 +++- lib/kobject.c | 18 +++++------------- 4 files changed, 17 insertions(+), 14 deletions(-) (limited to 'include/linux') diff --git a/Documentation/kobject.txt b/Documentation/kobject.txt index 51a8021ee532..f5d2aad65a67 100644 --- a/Documentation/kobject.txt +++ b/Documentation/kobject.txt @@ -118,6 +118,10 @@ the name of the kobject, call kobject_rename(): int kobject_rename(struct kobject *kobj, const char *new_name); +Note kobject_rename does perform any locking or have a solid notion of +what names are valid so the provide must provide their own sanity checking +and serialization. + There is a function called kobject_set_name() but that is legacy cruft and is being removed. If your code needs to call this function, it is incorrect and needs to be fixed. diff --git a/drivers/base/core.c b/drivers/base/core.c index 9649d1c422a4..8c2cc2648f5a 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1327,6 +1327,11 @@ EXPORT_SYMBOL_GPL(device_destroy); * device_rename - renames a device * @dev: the pointer to the struct device to be renamed * @new_name: the new name of the device + * + * It is the responsibility of the caller to provide mutual + * exclusion between two different calls of device_rename + * on the same device to ensure that new_name is valid and + * won't conflict with other devices. */ int device_rename(struct device *dev, char *new_name) { diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index b330e289d71f..39924a962207 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -20,6 +20,8 @@ struct kobject; struct module; +extern int kobject_set_name(struct kobject *kobj, const char *name, ...) + __attribute__((format(printf, 2, 3))); /* FIXME * The *owner field is no longer used, but leave around * until the tree gets cleaned up fully. @@ -147,7 +149,7 @@ static inline void sysfs_remove_dir(struct kobject *kobj) static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name) { - return 0; + return kobject_set_name(kobj, "%s", new_name); } static inline int sysfs_move_dir(struct kobject *kobj, diff --git a/lib/kobject.c b/lib/kobject.c index fbf0ae282376..ae6bb900bfb6 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -387,6 +387,11 @@ EXPORT_SYMBOL_GPL(kobject_init_and_add); * kobject_rename - change the name of an object * @kobj: object in question. * @new_name: object's new name + * + * It is the responsibility of the caller to provide mutual + * exclusion between two different calls of kobject_rename + * on the same kobject and to ensure that new_name is valid and + * won't conflict with other kobjects. */ int kobject_rename(struct kobject *kobj, const char *new_name) { @@ -401,19 +406,6 @@ int kobject_rename(struct kobject *kobj, const char *new_name) if (!kobj->parent) return -EINVAL; - /* see if this name is already in use */ - if (kobj->kset) { - struct kobject *temp_kobj; - temp_kobj = kset_find_obj(kobj->kset, new_name); - if (temp_kobj) { - printk(KERN_WARNING "kobject '%s' cannot be renamed " - "to '%s' as '%s' is already in existence.\n", - kobject_name(kobj), new_name, new_name); - kobject_put(temp_kobj); - return -EINVAL; - } - } - devpath = kobject_get_path(kobj, GFP_KERNEL); if (!devpath) { error = -ENOMEM; -- cgit v1.2.3-59-g8ed1b From 0b4a4fea253e1296222603ccc55430ed7cd9413a Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 3 Jul 2008 18:05:28 -0700 Subject: kobject: Cleanup kobject_rename and !CONFIG_SYSFS It finally dawned on me what the clean fix to sysfs_rename_dir calling kobject_set_name is. Move the work into kobject_rename where it belongs. The callers serialize us anyway so this is safe. Signed-off-by: Eric W. Biederman Acked-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 6 +----- include/linux/sysfs.h | 4 +--- lib/kobject.c | 17 +++++++++++++++-- 3 files changed, 17 insertions(+), 10 deletions(-) (limited to 'include/linux') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index c18342641cec..3a05a596e3b4 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -829,16 +829,12 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) if (!new_dentry) goto out_unlock; - /* rename kobject and sysfs_dirent */ + /* rename sysfs_dirent */ error = -ENOMEM; new_name = dup_name = kstrdup(new_name, GFP_KERNEL); if (!new_name) goto out_unlock; - error = kobject_set_name(kobj, "%s", new_name); - if (error) - goto out_unlock; - dup_name = sd->s_name; sd->s_name = new_name; diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 39924a962207..b330e289d71f 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -20,8 +20,6 @@ struct kobject; struct module; -extern int kobject_set_name(struct kobject *kobj, const char *name, ...) - __attribute__((format(printf, 2, 3))); /* FIXME * The *owner field is no longer used, but leave around * until the tree gets cleaned up fully. @@ -149,7 +147,7 @@ static inline void sysfs_remove_dir(struct kobject *kobj) static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name) { - return kobject_set_name(kobj, "%s", new_name); + return 0; } static inline int sysfs_move_dir(struct kobject *kobj, diff --git a/lib/kobject.c b/lib/kobject.c index ae6bb900bfb6..0487d1f64806 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -397,6 +397,7 @@ int kobject_rename(struct kobject *kobj, const char *new_name) { int error = 0; const char *devpath = NULL; + const char *dup_name = NULL, *name; char *devpath_string = NULL; char *envp[2]; @@ -420,15 +421,27 @@ int kobject_rename(struct kobject *kobj, const char *new_name) envp[0] = devpath_string; envp[1] = NULL; + name = dup_name = kstrdup(new_name, GFP_KERNEL); + if (!name) { + error = -ENOMEM; + goto out; + } + error = sysfs_rename_dir(kobj, new_name); + if (error) + goto out; + + /* Install the new kobject name */ + dup_name = kobj->name; + kobj->name = name; /* This function is mostly/only used for network interface. * Some hotplug package track interfaces by their name and * therefore want to know when the name is changed by the user. */ - if (!error) - kobject_uevent_env(kobj, KOBJ_MOVE, envp); + kobject_uevent_env(kobj, KOBJ_MOVE, envp); out: + kfree(dup_name); kfree(devpath_string); kfree(devpath); kobject_put(kobj); -- cgit v1.2.3-59-g8ed1b From 99178b036c97293a65004ff5ec5cff9f833aaecd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 26 Aug 2008 11:00:57 -0500 Subject: Driver core: add bus_sort_breadthfirst() function The PCI core wants to reorder the devices in the bus list. So move this functionality out of the pci core and into the driver core so that anyone else can also do this if needed. This also lets us change how struct device is attached to drivers in the future without messing with the PCI core. Acked-by: Jesse Barnes Signed-off-by: Greg Kroah-Hartman --- drivers/base/bus.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/probe.c | 50 +++++--------------------------------------------- include/linux/device.h | 3 +++ 3 files changed, 58 insertions(+), 45 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 39b9b58c6974..5aee1c0169ea 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -980,6 +980,56 @@ struct klist *bus_get_device_klist(struct bus_type *bus) } EXPORT_SYMBOL_GPL(bus_get_device_klist); +/* + * Yes, this forcably breaks the klist abstraction temporarily. It + * just wants to sort the klist, not change reference counts and + * take/drop locks rapidly in the process. It does all this while + * holding the lock for the list, so objects can't otherwise be + * added/removed while we're swizzling. + */ +static void device_insertion_sort_klist(struct device *a, struct list_head *list, + int (*compare)(const struct device *a, + const struct device *b)) +{ + struct list_head *pos; + struct klist_node *n; + struct device *b; + + list_for_each(pos, list) { + n = container_of(pos, struct klist_node, n_node); + b = container_of(n, struct device, knode_bus); + if (compare(a, b) <= 0) { + list_move_tail(&a->knode_bus.n_node, + &b->knode_bus.n_node); + return; + } + } + list_move_tail(&a->knode_bus.n_node, list); +} + +void bus_sort_breadthfirst(struct bus_type *bus, + int (*compare)(const struct device *a, + const struct device *b)) +{ + LIST_HEAD(sorted_devices); + struct list_head *pos, *tmp; + struct klist_node *n; + struct device *dev; + struct klist *device_klist; + + device_klist = bus_get_device_klist(bus); + + spin_lock(&device_klist->k_lock); + list_for_each_safe(pos, tmp, &device_klist->k_list) { + n = container_of(pos, struct klist_node, n_node); + dev = container_of(n, struct device, knode_bus); + device_insertion_sort_klist(dev, &sorted_devices, compare); + } + list_splice(&sorted_devices, &device_klist->k_list); + spin_unlock(&device_klist->k_lock); +} +EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); + int __init buses_init(void) { bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 36698e57b97f..dd9161a054e1 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1237,8 +1237,11 @@ EXPORT_SYMBOL(pci_scan_bridge); EXPORT_SYMBOL_GPL(pci_scan_child_bus); #endif -static int __init pci_sort_bf_cmp(const struct pci_dev *a, const struct pci_dev *b) +static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b) { + const struct pci_dev *a = to_pci_dev(d_a); + const struct pci_dev *b = to_pci_dev(d_b); + if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1; else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1; @@ -1251,50 +1254,7 @@ static int __init pci_sort_bf_cmp(const struct pci_dev *a, const struct pci_dev return 0; } -/* - * Yes, this forcably breaks the klist abstraction temporarily. It - * just wants to sort the klist, not change reference counts and - * take/drop locks rapidly in the process. It does all this while - * holding the lock for the list, so objects can't otherwise be - * added/removed while we're swizzling. - */ -static void __init pci_insertion_sort_klist(struct pci_dev *a, struct list_head *list) -{ - struct list_head *pos; - struct klist_node *n; - struct device *dev; - struct pci_dev *b; - - list_for_each(pos, list) { - n = container_of(pos, struct klist_node, n_node); - dev = container_of(n, struct device, knode_bus); - b = to_pci_dev(dev); - if (pci_sort_bf_cmp(a, b) <= 0) { - list_move_tail(&a->dev.knode_bus.n_node, &b->dev.knode_bus.n_node); - return; - } - } - list_move_tail(&a->dev.knode_bus.n_node, list); -} - void __init pci_sort_breadthfirst(void) { - LIST_HEAD(sorted_devices); - struct list_head *pos, *tmp; - struct klist_node *n; - struct device *dev; - struct pci_dev *pdev; - struct klist *device_klist; - - device_klist = bus_get_device_klist(&pci_bus_type); - - spin_lock(&device_klist->k_lock); - list_for_each_safe(pos, tmp, &device_klist->k_list) { - n = container_of(pos, struct klist_node, n_node); - dev = container_of(n, struct device, knode_bus); - pdev = to_pci_dev(dev); - pci_insertion_sort_klist(pdev, &sorted_devices); - } - list_splice(&sorted_devices, &device_klist->k_list); - spin_unlock(&device_klist->k_lock); + bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp); } diff --git a/include/linux/device.h b/include/linux/device.h index ec90e79f6a00..987f5912720a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -90,6 +90,9 @@ int __must_check bus_for_each_drv(struct bus_type *bus, struct device_driver *start, void *data, int (*fn)(struct device_driver *, void *)); +void bus_sort_breadthfirst(struct bus_type *bus, + int (*compare)(const struct device *a, + const struct device *b)); /* * Bus notifiers: Get notified of addition/removal of devices * and binding/unbinding of drivers to devices. -- cgit v1.2.3-59-g8ed1b