From 4668c7a2940d134bea50058e138591b97485c5da Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 27 Mar 2023 23:37:32 +0900 Subject: [PATCH] fault-inject: allow configuration via configfs This provides a helper function to allow configuration of fault-injection for configfs-based drivers. The config items created by this function have the same interface as the one created under debugfs by fault_create_debugfs_attr(). Signed-off-by: Akinobu Mita Link: https://lore.kernel.org/r/20230327143733.14599-2-akinobu.mita@gmail.com Signed-off-by: Jens Axboe --- include/linux/fault-inject.h | 22 ++++ lib/Kconfig.debug | 13 ++- lib/fault-inject.c | 191 +++++++++++++++++++++++++++++++++++ 3 files changed, 225 insertions(+), 1 deletion(-) diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index 444236dadcf0..481abf530b3c 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -6,6 +6,7 @@ #include #include +#include #include #include @@ -65,6 +66,27 @@ static inline struct dentry *fault_create_debugfs_attr(const char *name, #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ +#ifdef CONFIG_FAULT_INJECTION_CONFIGFS + +struct fault_config { + struct fault_attr attr; + struct config_group group; +}; + +void fault_config_init(struct fault_config *config, const char *name); + +#else /* CONFIG_FAULT_INJECTION_CONFIGFS */ + +struct fault_config { +}; + +static inline void fault_config_init(struct fault_config *config, + const char *name) +{ +} + +#endif /* CONFIG_FAULT_INJECTION_CONFIGFS */ + #endif /* CONFIG_FAULT_INJECTION */ struct kmem_cache; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index c8b379e2e9ad..e700b29d7756 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1958,9 +1958,20 @@ config FAIL_SUNRPC Provide fault-injection capability for SunRPC and its consumers. +config FAULT_INJECTION_CONFIGFS + bool "Configfs interface for fault-injection capabilities" + depends on FAULT_INJECTION && CONFIGFS_FS + help + This option allows configfs-based drivers to dynamically configure + fault-injection via configfs. Each parameter for driver-specific + fault-injection can be made visible as a configfs attribute in a + configfs group. + + config FAULT_INJECTION_STACKTRACE_FILTER bool "stacktrace filter for fault-injection capabilities" - depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT + depends on FAULT_INJECTION + depends on (FAULT_INJECTION_DEBUG_FS || FAULT_INJECTION_CONFIGFS) && STACKTRACE_SUPPORT select STACKTRACE depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 help diff --git a/lib/fault-inject.c b/lib/fault-inject.c index 6cff320c4eb4..d608f9b48c10 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -244,3 +244,194 @@ struct dentry *fault_create_debugfs_attr(const char *name, EXPORT_SYMBOL_GPL(fault_create_debugfs_attr); #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ + +#ifdef CONFIG_FAULT_INJECTION_CONFIGFS + +/* These configfs attribute utilities are copied from drivers/block/null_blk/main.c */ + +static ssize_t fault_uint_attr_show(unsigned int val, char *page) +{ + return snprintf(page, PAGE_SIZE, "%u\n", val); +} + +static ssize_t fault_ulong_attr_show(unsigned long val, char *page) +{ + return snprintf(page, PAGE_SIZE, "%lu\n", val); +} + +static ssize_t fault_bool_attr_show(bool val, char *page) +{ + return snprintf(page, PAGE_SIZE, "%u\n", val); +} + +static ssize_t fault_atomic_t_attr_show(atomic_t val, char *page) +{ + return snprintf(page, PAGE_SIZE, "%d\n", atomic_read(&val)); +} + +static ssize_t fault_uint_attr_store(unsigned int *val, const char *page, size_t count) +{ + unsigned int tmp; + int result; + + result = kstrtouint(page, 0, &tmp); + if (result < 0) + return result; + + *val = tmp; + return count; +} + +static ssize_t fault_ulong_attr_store(unsigned long *val, const char *page, size_t count) +{ + int result; + unsigned long tmp; + + result = kstrtoul(page, 0, &tmp); + if (result < 0) + return result; + + *val = tmp; + return count; +} + +static ssize_t fault_bool_attr_store(bool *val, const char *page, size_t count) +{ + bool tmp; + int result; + + result = kstrtobool(page, &tmp); + if (result < 0) + return result; + + *val = tmp; + return count; +} + +static ssize_t fault_atomic_t_attr_store(atomic_t *val, const char *page, size_t count) +{ + int tmp; + int result; + + result = kstrtoint(page, 0, &tmp); + if (result < 0) + return result; + + atomic_set(val, tmp); + return count; +} + +#define CONFIGFS_ATTR_NAMED(_pfx, _name, _attr_name) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .ca_name = _attr_name, \ + .ca_mode = 0644, \ + .ca_owner = THIS_MODULE, \ + .show = _pfx##_name##_show, \ + .store = _pfx##_name##_store, \ +} + +static struct fault_config *to_fault_config(struct config_item *item) +{ + return container_of(to_config_group(item), struct fault_config, group); +} + +#define FAULT_CONFIGFS_ATTR_NAMED(NAME, ATTR_NAME, MEMBER, TYPE) \ +static ssize_t fault_##NAME##_show(struct config_item *item, char *page) \ +{ \ + return fault_##TYPE##_attr_show(to_fault_config(item)->attr.MEMBER, page); \ +} \ +static ssize_t fault_##NAME##_store(struct config_item *item, const char *page, size_t count) \ +{ \ + struct fault_config *config = to_fault_config(item); \ + return fault_##TYPE##_attr_store(&config->attr.MEMBER, page, count); \ +} \ +CONFIGFS_ATTR_NAMED(fault_, NAME, ATTR_NAME) + +#define FAULT_CONFIGFS_ATTR(NAME, TYPE) \ + FAULT_CONFIGFS_ATTR_NAMED(NAME, __stringify(NAME), NAME, TYPE) + +FAULT_CONFIGFS_ATTR(probability, ulong); +FAULT_CONFIGFS_ATTR(interval, ulong); +FAULT_CONFIGFS_ATTR(times, atomic_t); +FAULT_CONFIGFS_ATTR(space, atomic_t); +FAULT_CONFIGFS_ATTR(verbose, ulong); +FAULT_CONFIGFS_ATTR_NAMED(ratelimit_interval, "verbose_ratelimit_interval_ms", + ratelimit_state.interval, uint); +FAULT_CONFIGFS_ATTR_NAMED(ratelimit_burst, "verbose_ratelimit_burst", + ratelimit_state.burst, uint); +FAULT_CONFIGFS_ATTR_NAMED(task_filter, "task-filter", task_filter, bool); + +#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER + +static ssize_t fault_stacktrace_depth_show(struct config_item *item, char *page) +{ + return fault_ulong_attr_show(to_fault_config(item)->attr.stacktrace_depth, page); +} + +static ssize_t fault_stacktrace_depth_store(struct config_item *item, const char *page, + size_t count) +{ + int result; + unsigned long tmp; + + result = kstrtoul(page, 0, &tmp); + if (result < 0) + return result; + + to_fault_config(item)->attr.stacktrace_depth = + min_t(unsigned long, tmp, MAX_STACK_TRACE_DEPTH); + + return count; +} + +CONFIGFS_ATTR_NAMED(fault_, stacktrace_depth, "stacktrace-depth"); + +static ssize_t fault_xul_attr_show(unsigned long val, char *page) +{ + return snprintf(page, PAGE_SIZE, + sizeof(val) == sizeof(u32) ? "0x%08lx\n" : "0x%016lx\n", val); +} + +static ssize_t fault_xul_attr_store(unsigned long *val, const char *page, size_t count) +{ + return fault_ulong_attr_store(val, page, count); +} + +FAULT_CONFIGFS_ATTR_NAMED(require_start, "require-start", require_start, xul); +FAULT_CONFIGFS_ATTR_NAMED(require_end, "require-end", require_end, xul); +FAULT_CONFIGFS_ATTR_NAMED(reject_start, "reject-start", reject_start, xul); +FAULT_CONFIGFS_ATTR_NAMED(reject_end, "reject-end", reject_end, xul); + +#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */ + +static struct configfs_attribute *fault_config_attrs[] = { + &fault_attr_probability, + &fault_attr_interval, + &fault_attr_times, + &fault_attr_space, + &fault_attr_verbose, + &fault_attr_ratelimit_interval, + &fault_attr_ratelimit_burst, + &fault_attr_task_filter, +#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER + &fault_attr_stacktrace_depth, + &fault_attr_require_start, + &fault_attr_require_end, + &fault_attr_reject_start, + &fault_attr_reject_end, +#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */ + NULL, +}; + +static const struct config_item_type fault_config_type = { + .ct_attrs = fault_config_attrs, + .ct_owner = THIS_MODULE, +}; + +void fault_config_init(struct fault_config *config, const char *name) +{ + config_group_init_type_name(&config->group, name, &fault_config_type); +} +EXPORT_SYMBOL_GPL(fault_config_init); + +#endif /* CONFIG_FAULT_INJECTION_CONFIGFS */