diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 15:05:40 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 15:05:40 -0700 |
commit | a5e6b135bdff649e4330f98e2e80dbb1984f7e77 (patch) | |
tree | 475bfb1163c59d1370fd77415255afba768f9520 /drivers/firmware | |
parent | 971f115a50afbe409825c9f3399d5a3b9aca4381 (diff) | |
parent | 9d90c8d9cde929cbc575098e825d7c29d9f45054 (diff) |
Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (50 commits)
printk: do not mangle valid userspace syslog prefixes
efivars: Add Documentation
efivars: Expose efivars functionality to external drivers.
efivars: Parameterize operations.
efivars: Split out variable registration
efivars: parameterize efivars
efivars: Make efivars bin_attributes dynamic
efivars: move efivars globals into struct efivars
drivers:misc: ti-st: fix debugging code
kref: Fix typo in kref documentation
UIO: add PRUSS UIO driver support
Fix spelling mistakes in Documentation/zh_CN/SubmittingPatches
firmware: Fix unaligned memory accesses in dmi-sysfs
firmware: Add documentation for /sys/firmware/dmi
firmware: Expose DMI type 15 System Event Log
firmware: Break out system_event_log in dmi-sysfs
firmware: Basic dmi-sysfs support
firmware: Add DMI entry types to the headers
Driver core: convert platform_{get,set}_drvdata to static inline functions
Translate linux-2.6/Documentation/magic-number.txt into Chinese
...
Diffstat (limited to 'drivers/firmware')
-rw-r--r-- | drivers/firmware/Kconfig | 11 | ||||
-rw-r--r-- | drivers/firmware/Makefile | 1 | ||||
-rw-r--r-- | drivers/firmware/dmi-sysfs.c | 696 | ||||
-rw-r--r-- | drivers/firmware/efivars.c | 343 |
4 files changed, 913 insertions, 138 deletions
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index e710424b59e..3c56afc5eb1 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -113,6 +113,17 @@ config DMIID information from userspace through /sys/class/dmi/id/ or if you want DMI-based module auto-loading. +config DMI_SYSFS + tristate "DMI table support in sysfs" + depends on SYSFS && DMI + default n + help + Say Y or M here to enable the exporting of the raw DMI table + data via sysfs. This is useful for consuming the data without + requiring any access to /dev/mem at all. Tables are found + under /sys/firmware/dmi when this option is enabled and + loaded. + config ISCSI_IBFT_FIND bool "iSCSI Boot Firmware Table Attributes" depends on X86 diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 1c3c17343db..20c17fca123 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -2,6 +2,7 @@ # Makefile for the linux kernel. # obj-$(CONFIG_DMI) += dmi_scan.o +obj-$(CONFIG_DMI_SYSFS) += dmi-sysfs.o obj-$(CONFIG_EDD) += edd.o obj-$(CONFIG_EFI_VARS) += efivars.o obj-$(CONFIG_EFI_PCDP) += pcdp.o diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c new file mode 100644 index 00000000000..eb26d62e518 --- /dev/null +++ b/drivers/firmware/dmi-sysfs.c @@ -0,0 +1,696 @@ +/* + * dmi-sysfs.c + * + * This module exports the DMI tables read-only to userspace through the + * sysfs file system. + * + * Data is currently found below + * /sys/firmware/dmi/... + * + * DMI attributes are presented in attribute files with names + * formatted using %d-%d, so that the first integer indicates the + * structure type (0-255), and the second field is the instance of that + * entry. + * + * Copyright 2011 Google, Inc. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kobject.h> +#include <linux/dmi.h> +#include <linux/capability.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/io.h> + +#define MAX_ENTRY_TYPE 255 /* Most of these aren't used, but we consider + the top entry type is only 8 bits */ + +struct dmi_sysfs_entry { + struct dmi_header dh; + struct kobject kobj; + int instance; + int position; + struct list_head list; + struct kobject *child; +}; + +/* + * Global list of dmi_sysfs_entry. Even though this should only be + * manipulated at setup and teardown, the lazy nature of the kobject + * system means we get lazy removes. + */ +static LIST_HEAD(entry_list); +static DEFINE_SPINLOCK(entry_list_lock); + +/* dmi_sysfs_attribute - Top level attribute. used by all entries. */ +struct dmi_sysfs_attribute { + struct attribute attr; + ssize_t (*show)(struct dmi_sysfs_entry *entry, char *buf); +}; + +#define DMI_SYSFS_ATTR(_entry, _name) \ +struct dmi_sysfs_attribute dmi_sysfs_attr_##_entry##_##_name = { \ + .attr = {.name = __stringify(_name), .mode = 0400}, \ + .show = dmi_sysfs_##_entry##_##_name, \ +} + +/* + * dmi_sysfs_mapped_attribute - Attribute where we require the entry be + * mapped in. Use in conjunction with dmi_sysfs_specialize_attr_ops. + */ +struct dmi_sysfs_mapped_attribute { + struct attribute attr; + ssize_t (*show)(struct dmi_sysfs_entry *entry, + const struct dmi_header *dh, + char *buf); +}; + +#define DMI_SYSFS_MAPPED_ATTR(_entry, _name) \ +struct dmi_sysfs_mapped_attribute dmi_sysfs_attr_##_entry##_##_name = { \ + .attr = {.name = __stringify(_name), .mode = 0400}, \ + .show = dmi_sysfs_##_entry##_##_name, \ +} + +/************************************************* + * Generic DMI entry support. + *************************************************/ +static void dmi_entry_free(struct kobject *kobj) +{ + kfree(kobj); +} + +static struct dmi_sysfs_entry *to_entry(struct kobject *kobj) +{ + return container_of(kobj, struct dmi_sysfs_entry, kobj); +} + +static struct dmi_sysfs_attribute *to_attr(struct attribute *attr) +{ + return container_of(attr, struct dmi_sysfs_attribute, attr); +} + +static ssize_t dmi_sysfs_attr_show(struct kobject *kobj, + struct attribute *_attr, char *buf) +{ + struct dmi_sysfs_entry *entry = to_entry(kobj); + struct dmi_sysfs_attribute *attr = to_attr(_attr); + + /* DMI stuff is only ever admin visible */ + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + return attr->show(entry, buf); +} + +static const struct sysfs_ops dmi_sysfs_attr_ops = { + .show = dmi_sysfs_attr_show, +}; + +typedef ssize_t (*dmi_callback)(struct dmi_sysfs_entry *, + const struct dmi_header *dh, void *); + +struct find_dmi_data { + struct dmi_sysfs_entry *entry; + dmi_callback callback; + void *private; + int instance_countdown; + ssize_t ret; +}; + +static void find_dmi_entry_helper(const struct dmi_header *dh, + void *_data) +{ + struct find_dmi_data *data = _data; + struct dmi_sysfs_entry *entry = data->entry; + + /* Is this the entry we want? */ + if (dh->type != entry->dh.type) + return; + + if (data->instance_countdown != 0) { + /* try the next instance? */ + data->instance_countdown--; + return; + } + + /* + * Don't ever revisit the instance. Short circuit later + * instances by letting the instance_countdown run negative + */ + data->instance_countdown--; + + /* Found the entry */ + data->ret = data->callback(entry, dh, data->private); +} + +/* State for passing the read parameters through dmi_find_entry() */ +struct dmi_read_state { + char *buf; + loff_t pos; + size_t count; +}; + +static ssize_t find_dmi_entry(struct dmi_sysfs_entry *entry, + dmi_callback callback, void *private) +{ + struct find_dmi_data data = { + .entry = entry, + .callback = callback, + .private = private, + .instance_countdown = entry->instance, + .ret = -EIO, /* To signal the entry disappeared */ + }; + int ret; + + ret = dmi_walk(find_dmi_entry_helper, &data); + /* This shouldn't happen, but just in case. */ + if (ret) + return -EINVAL; + return data.ret; +} + +/* + * Calculate and return the byte length of the dmi entry identified by + * dh. This includes both the formatted portion as well as the + * unformatted string space, including the two trailing nul characters. + */ +static size_t dmi_entry_length(const struct dmi_header *dh) +{ + const char *p = (const char *)dh; + + p += dh->length; + + while (p[0] || p[1]) + p++; + + return 2 + p - (const char *)dh; +} + +/************************************************* + * Support bits for specialized DMI entry support + *************************************************/ +struct dmi_entry_attr_show_data { + struct attribute *attr; + char *buf; +}; + +static ssize_t dmi_entry_attr_show_helper(struct dmi_sysfs_entry *entry, + const struct dmi_header *dh, + void *_data) +{ + struct dmi_entry_attr_show_data *data = _data; + struct dmi_sysfs_mapped_attribute *attr; + + attr = container_of(data->attr, + struct dmi_sysfs_mapped_attribute, attr); + return attr->show(entry, dh, data->buf); +} + +static ssize_t dmi_entry_attr_show(struct kobject *kobj, + struct attribute *attr, + char *buf) +{ + struct dmi_entry_attr_show_data data = { + .attr = attr, + .buf = buf, + }; + /* Find the entry according to our parent and call the + * normalized show method hanging off of the attribute */ + return find_dmi_entry(to_entry(kobj->parent), + dmi_entry_attr_show_helper, &data); +} + +static const struct sysfs_ops dmi_sysfs_specialize_attr_ops = { + .show = dmi_entry_attr_show, +}; + +/************************************************* + * Specialized DMI entry support. + *************************************************/ + +/*** Type 15 - System Event Table ***/ + +#define DMI_SEL_ACCESS_METHOD_IO8 0x00 +#define DMI_SEL_ACCESS_METHOD_IO2x8 0x01 +#define DMI_SEL_ACCESS_METHOD_IO16 0x02 +#define DMI_SEL_ACCESS_METHOD_PHYS32 0x03 +#define DMI_SEL_ACCESS_METHOD_GPNV 0x04 + +struct dmi_system_event_log { + struct dmi_header header; + u16 area_length; + u16 header_start_offset; + u16 data_start_offset; + u8 access_method; + u8 status; + u32 change_token; + union { + struct { + u16 index_addr; + u16 data_addr; + } io; + u32 phys_addr32; + u16 gpnv_handle; + u32 access_method_address; + }; + u8 header_format; + u8 type_descriptors_supported_count; + u8 per_log_type_descriptor_length; + u8 supported_log_type_descriptos[0]; +} __packed; + +#define DMI_SYSFS_SEL_FIELD(_field) \ +static ssize_t dmi_sysfs_sel_##_field(struct dmi_sysfs_entry *entry, \ + const struct dmi_header *dh, \ + char *buf) \ +{ \ + struct dmi_system_event_log sel; \ + if (sizeof(sel) > dmi_entry_length(dh)) \ + return -EIO; \ + memcpy(&sel, dh, sizeof(sel)); \ + return sprintf(buf, "%u\n", sel._field); \ +} \ +static DMI_SYSFS_MAPPED_ATTR(sel, _field) + +DMI_SYSFS_SEL_FIELD(area_length); +DMI_SYSFS_SEL_FIELD(header_start_offset); +DMI_SYSFS_SEL_FIELD(data_start_offset); +DMI_SYSFS_SEL_FIELD(access_method); +DMI_SYSFS_SEL_FIELD(status); +DMI_SYSFS_SEL_FIELD(change_token); +DMI_SYSFS_SEL_FIELD(access_method_address); +DMI_SYSFS_SEL_FIELD(header_format); +DMI_SYSFS_SEL_FIELD(type_descriptors_supported_count); +DMI_SYSFS_SEL_FIELD(per_log_type_descriptor_length); + +static struct attribute *dmi_sysfs_sel_attrs[] = { + &dmi_sysfs_attr_sel_area_length.attr, + &dmi_sysfs_attr_sel_header_start_offset.attr, + &dmi_sysfs_attr_sel_data_start_offset.attr, + &dmi_sysfs_attr_sel_access_method.attr, + &dmi_sysfs_attr_sel_status.attr, + &dmi_sysfs_attr_sel_change_token.attr, + &dmi_sysfs_attr_sel_access_method_address.attr, + &dmi_sysfs_attr_sel_header_format.attr, + &dmi_sysfs_attr_sel_type_descriptors_supported_count.attr, + &dmi_sysfs_attr_sel_per_log_type_descriptor_length.attr, + NULL, +}; + + +static struct kobj_type dmi_system_event_log_ktype = { + .release = dmi_entry_free, + .sysfs_ops = &dmi_sysfs_specialize_attr_ops, + .default_attrs = dmi_sysfs_sel_attrs, +}; + +typedef u8 (*sel_io_reader)(const struct dmi_system_event_log *sel, + loff_t offset); + +static DEFINE_MUTEX(io_port_lock); + +static u8 read_sel_8bit_indexed_io(const struct dmi_system_event_log *sel, + loff_t offset) +{ + u8 ret; + + mutex_lock(&io_port_lock); + outb((u8)offset, sel->io.index_addr); + ret = inb(sel->io.data_addr); + mutex_unlock(&io_port_lock); + return ret; +} + +static u8 read_sel_2x8bit_indexed_io(const struct dmi_system_event_log *sel, + loff_t offset) +{ + u8 ret; + + mutex_lock(&io_port_lock); + outb((u8)offset, sel->io.index_addr); + outb((u8)(offset >> 8), sel->io.index_addr + 1); + ret = inb(sel->io.data_addr); + mutex_unlock(&io_port_lock); + return ret; +} + +static u8 read_sel_16bit_indexed_io(const struct dmi_system_event_log *sel, + loff_t offset) +{ + u8 ret; + + mutex_lock(&io_port_lock); + outw((u16)offset, sel->io.index_addr); + ret = inb(sel->io.data_addr); + mutex_unlock(&io_port_lock); + return ret; +} + +static sel_io_reader sel_io_readers[] = { + [DMI_SEL_ACCESS_METHOD_IO8] = read_sel_8bit_indexed_io, + [DMI_SEL_ACCESS_METHOD_IO2x8] = read_sel_2x8bit_indexed_io, + [DMI_SEL_ACCESS_METHOD_IO16] = read_sel_16bit_indexed_io, +}; + +static ssize_t dmi_sel_raw_read_io(struct dmi_sysfs_entry *entry, + const struct dmi_system_event_log *sel, + char *buf, loff_t pos, size_t count) +{ + ssize_t wrote = 0; + + sel_io_reader io_reader = sel_io_readers[sel->access_method]; + + while (count && pos < sel->area_length) { + count--; + *(buf++) = io_reader(sel, pos++); + wrote++; + } + + return wrote; +} + +static ssize_t dmi_sel_raw_read_phys32(struct dmi_sysfs_entry *entry, + const struct dmi_system_event_log *sel, + char *buf, loff_t pos, size_t count) +{ + u8 __iomem *mapped; + ssize_t wrote = 0; + + mapped = ioremap(sel->access_method_address, sel->area_length); + if (!mapped) + return -EIO; + + while (count && pos < sel->area_length) { + count--; + *(buf++) = readb(mapped + pos++); + wrote++; + } + + iounmap(mapped); + return wrote; +} + +static ssize_t dmi_sel_raw_read_helper(struct dmi_sysfs_entry *entry, + const struct dmi_header *dh, + void *_state) +{ + struct dmi_read_state *state = _state; + struct dmi_system_event_log sel; + + if (sizeof(sel) > dmi_entry_length(dh)) + return -EIO; + + memcpy(&sel, dh, sizeof(sel)); + + switch (sel.access_method) { + case DMI_SEL_ACCESS_METHOD_IO8: + case DMI_SEL_ACCESS_METHOD_IO2x8: + case DMI_SEL_ACCESS_METHOD_IO16: + return dmi_sel_raw_read_io(entry, &sel, state->buf, + state->pos, state->count); + case DMI_SEL_ACCESS_METHOD_PHYS32: + return dmi_sel_raw_read_phys32(entry, &sel, state->buf, + state->pos, state->count); + case DMI_SEL_ACCESS_METHOD_GPNV: + pr_info("dmi-sysfs: GPNV support missing.\n"); + return -EIO; + default: + pr_info("dmi-sysfs: Unknown access method %02x\n", + sel.access_method); + return -EIO; + } +} + +static ssize_t dmi_sel_raw_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + struct dmi_sysfs_entry *entry = to_entry(kobj->parent); + struct dmi_read_state state = { + .buf = buf, + .pos = pos, + .count = count, + }; + + return find_dmi_entry(entry, dmi_sel_raw_read_helper, &state); +} + +static struct bin_attribute dmi_sel_raw_attr = { + .attr = {.name = "raw_event_log", .mode = 0400}, + .read = dmi_sel_raw_read, +}; + +static int dmi_system_event_log(struct dmi_sysfs_entry *entry) +{ + int ret; + + entry->child = kzalloc(sizeof(*entry->child), GFP_KERNEL); + if (!entry->child) + return -ENOMEM; + ret = kobject_init_and_add(entry->child, + &dmi_system_event_log_ktype, + &entry->kobj, + "system_event_log"); + if (ret) + goto out_free; + + ret = sysfs_create_bin_file(entry->child, &dmi_sel_raw_attr); + if (ret) + goto out_del; + + return 0; + +out_del: + kobject_del(entry->child); +out_free: + kfree(entry->child); + return ret; +} + +/************************************************* + * Generic DMI entry support. + *************************************************/ + +static ssize_t dmi_sysfs_entry_length(struct dmi_sysfs_entry *entry, char *buf) +{ + return sprintf(buf, "%d\n", entry->dh.length); +} + +static ssize_t dmi_sysfs_entry_handle(struct dmi_sysfs_entry *entry, char *buf) +{ + return sprintf(buf, "%d\n", entry->dh.handle); +} + +static ssize_t dmi_sysfs_entry_type(struct dmi_sysfs_entry *entry, char *buf) +{ + return sprintf(buf, "%d\n", entry->dh.type); +} + +static ssize_t dmi_sysfs_entry_instance(struct dmi_sysfs_entry *entry, + char *buf) +{ + return sprintf(buf, "%d\n", entry->instance); +} + +static ssize_t dmi_sysfs_entry_position(struct dmi_sysfs_entry *entry, + char *buf) +{ + return sprintf(buf, "%d\n", entry->position); +} + +static DMI_SYSFS_ATTR(entry, length); +static DMI_SYSFS_ATTR(entry, handle); +static DMI_SYSFS_ATTR(entry, type); +static DMI_SYSFS_ATTR(entry, instance); +static DMI_SYSFS_ATTR(entry, position); + +static struct attribute *dmi_sysfs_entry_attrs[] = { + &dmi_sysfs_attr_entry_length.attr, + &dmi_sysfs_attr_entry_handle.attr, + &dmi_sysfs_attr_entry_type.attr, + &dmi_sysfs_attr_entry_instance.attr, + &dmi_sysfs_attr_entry_position.attr, + NULL, +}; + +static ssize_t dmi_entry_raw_read_helper(struct dmi_sysfs_entry *entry, + const struct dmi_header *dh, + void *_state) +{ + struct dmi_read_state *state = _state; + size_t entry_length; + + entry_length = dmi_entry_length(dh); + + return memory_read_from_buffer(state->buf, state->count, + &state->pos, dh, entry_length); +} + +static ssize_t dmi_entry_raw_read(struct file *filp, + struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + struct dmi_sysfs_entry *entry = to_entry(kobj); + struct dmi_read_state state = { + .buf = buf, + .pos = pos, + .count = count, + }; + + return find_dmi_entry(entry, dmi_entry_raw_read_helper, &state); +} + +static const struct bin_attribute dmi_entry_raw_attr = { + .attr = {.name = "raw", .mode = 0400}, + .read = dmi_entry_raw_read, +}; + +static void dmi_sysfs_entry_release(struct kobject *kobj) +{ + struct dmi_sysfs_entry *entry = to_entry(kobj); + sysfs_remove_bin_file(&entry->kobj, &dmi_entry_raw_attr); + spin_lock(&entry_list_lock); + list_del(&entry->list); + spin_unlock(&entry_list_lock); + kfree(entry); +} + +static struct kobj_type dmi_sysfs_entry_ktype = { + .release = dmi_sysfs_entry_release, + .sysfs_ops = &dmi_sysfs_attr_ops, + .default_attrs = dmi_sysfs_entry_attrs, +}; + +static struct kobject *dmi_kobj; +static struct kset *dmi_kset; + +/* Global count of all instances seen. Only for setup */ +static int __initdata instance_counts[MAX_ENTRY_TYPE + 1]; + +/* Global positional count of all entries seen. Only for setup */ +static int __initdata position_count; + +static void __init dmi_sysfs_register_handle(const struct dmi_header *dh, + void *_ret) +{ + struct dmi_sysfs_entry *entry; + int *ret = _ret; + + /* If a previous entry saw an error, short circuit */ + if (*ret) + return; + + /* Allocate and register a new entry into the entries set */ + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) { + *ret = -ENOMEM; + return; + } + + /* Set the key */ + memcpy(&entry->dh, dh, sizeof(*dh)); + entry->instance = instance_counts[dh->type]++; + entry->position = position_count++; + + entry->kobj.kset = dmi_kset; + *ret = kobject_init_and_add(&entry->kobj, &dmi_sysfs_entry_ktype, NULL, + "%d-%d", dh->type, entry->instance); + + if (*ret) { + kfree(entry); + return; + } + + /* Thread on the global list for cleanup */ + spin_lock(&entry_list_lock); + list_add_tail(&entry->list, &entry_list); + spin_unlock(&entry_list_lock); + + /* Handle specializations by type */ + switch (dh->type) { + case DMI_ENTRY_SYSTEM_EVENT_LOG: + *ret = dmi_system_event_log(entry); + break; + default: + /* No specialization */ + break; + } + if (*ret) + goto out_err; + + /* Create the raw binary file to access the entry */ + *ret = sysfs_create_bin_file(&entry->kobj, &dmi_entry_raw_attr); + if (*ret) + goto out_err; + + return; +out_err: + kobject_put(entry->child); + kobject_put(&entry->kobj); + return; +} + +static void cleanup_entry_list(void) +{ + struct dmi_sysfs_entry *entry, *next; + + /* No locks, we are on our way out */ + list_for_each_entry_safe(entry, next, &entry_list, list) { + kobject_put(entry->child); + kobject_put(&entry->kobj); + } +} + +static int __init dmi_sysfs_init(void) +{ + int error = -ENOMEM; + int val; + + /* Set up our directory */ + dmi_kobj = kobject_create_and_add("dmi", firmware_kobj); + if (!dmi_kobj) + goto err; + + dmi_kset = kset_create_and_add("entries", NULL, dmi_kobj); + if (!dmi_kset) + goto err; + + val = 0; + error = dmi_walk(dmi_sysfs_register_handle, &val); + if (error) + goto err; + if (val) { + error = val; + goto err; + } + + pr_debug("dmi-sysfs: loaded.\n"); + + return 0; +err: + cleanup_entry_list(); + kset_unregister(dmi_kset); + kobject_put(dmi_kobj); + return error; +} + +/* clean up everything. */ +static void __exit dmi_sysfs_exit(void) +{ + pr_debug("dmi-sysfs: unloading.\n"); + cleanup_entry_list(); + kset_unregister(dmi_kset); + kobject_put(dmi_kobj); +} + +module_init(dmi_sysfs_init); +module_exit(dmi_sysfs_exit); + +MODULE_AUTHOR("Mike Waychison <mikew@google.com>"); +MODULE_DESCRIPTION("DMI sysfs support"); +MODULE_LICENSE("GPL"); diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index 2a62ec6390e..ff0c373e3bb 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -90,17 +90,6 @@ MODULE_LICENSE("GPL"); MODULE_VERSION(EFIVARS_VERSION); /* - * efivars_lock protects two things: - * 1) efivar_list - adds, removals, reads, writes - * 2) efi.[gs]et_variable() calls. - * It must not be held when creating sysfs entries or calling kmalloc. - * efi.get_next_variable() is only called from efivars_init(), - * which is protected by the BKL, so that path is safe. - */ -static DEFINE_SPINLOCK(efivars_lock); -static LIST_HEAD(efivar_list); - -/* * The maximum size of VariableName + Data = 1024 * Therefore, it's reasonable to save that much * space in each part of the structure, @@ -118,6 +107,7 @@ struct efi_variable { struct efivar_entry { + struct efivars *efivars; struct efi_variable var; struct list_head list; struct kobject kobj; @@ -144,9 +134,10 @@ struct efivar_attribute efivar_attr_##_name = { \ * Prototype for sysfs creation function */ static int -efivar_create_sysfs_entry(unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid); +efivar_create_sysfs_entry(struct efivars *efivars, + unsigned long variable_name_size, + efi_char16_t *variable_name, + efi_guid_t *vendor_guid); /* Return the number of unicode characters in data */ static unsigned long @@ -170,18 +161,18 @@ utf8_strsize(efi_char16_t *data, unsigned long maxlength) } static efi_status_t -get_var_data(struct efi_variable *var) +get_var_data(struct efivars *efivars, struct efi_variable *var) { efi_status_t status; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); var->DataSize = 1024; - status = efi.get_variable(var->VariableName, - &var->VendorGuid, - &var->Attributes, - &var->DataSize, - var->Data); - spin_unlock(&efivars_lock); + status = efivars->ops->get_variable(var->VariableName, + &var->VendorGuid, + &var->Attributes, + &var->DataSize, + var->Data); + spin_unlock(&efivars->lock); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n", status); @@ -215,7 +206,7 @@ efivar_attr_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -238,7 +229,7 @@ efivar_size_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -255,7 +246,7 @@ efivar_data_read(struct efivar_entry *entry, char *buf) if (!entry || !buf) return -EINVAL; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -270,6 +261,7 @@ static ssize_t efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) { struct efi_variable *new_var, *var = &entry->var; + struct efivars *efivars = entry->efivars; efi_status_t status = EFI_NOT_FOUND; if (count != sizeof(struct efi_variable)) @@ -291,14 +283,14 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) return -EINVAL; } - spin_lock(&efivars_lock); - status = efi.set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); + spin_lock(&efivars->lock); + status = efivars->ops->set_variable(new_var->VariableName, + &new_var->VendorGuid, + new_var->Attributes, + new_var->DataSize, + new_var->Data); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", @@ -319,7 +311,7 @@ efivar_show_raw(struct efivar_entry *entry, char *buf) if (!entry || !buf) return 0; - status = get_var_data(var); + status = get_var_data(entry->efivars, var); if (status != EFI_SUCCESS) return -EIO; @@ -407,6 +399,7 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, char *buf, loff_t pos, size_t count) { struct efi_variable *new_var = (struct efi_variable *)buf; + struct efivars *efivars = bin_attr->private; struct efivar_entry *search_efivar, *n; unsigned long strsize1, strsize2; efi_status_t status = EFI_NOT_FOUND; @@ -415,12 +408,12 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, if (!capable(CAP_SYS_ADMIN)) return -EACCES; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); /* * Does this variable already exist? */ - list_for_each_entry_safe(search_efivar, n, &efivar_list, list) { + list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); strsize2 = utf8_strsize(new_var->VariableName, 1024); if (strsize1 == strsize2 && @@ -433,28 +426,31 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, } } if (found) { - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EINVAL; } /* now *really* create the variable via EFI */ - status = efi.set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); + status = efivars->ops->set_variable(new_var->VariableName, + &new_var->VendorGuid, + new_var->Attributes, + new_var->DataSize, + new_var->Data); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", status); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EIO; } - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); /* Create the entry in sysfs. Locking is not required here */ - status = efivar_create_sysfs_entry(utf8_strsize(new_var->VariableName, - 1024), new_var->VariableName, &new_var->VendorGuid); + status = efivar_create_sysfs_entry(efivars, + utf8_strsize(new_var->VariableName, + 1024), + new_var->VariableName, + &new_var->VendorGuid); if (status) { printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n"); } @@ -466,6 +462,7 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, char *buf, loff_t pos, size_t count) { struct efi_variable *del_var = (struct efi_variable *)buf; + struct efivars *efivars = bin_attr->private; struct efivar_entry *search_efivar, *n; unsigned long strsize1, strsize2; efi_status_t status = EFI_NOT_FOUND; @@ -474,12 +471,12 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, if (!capable(CAP_SYS_ADMIN)) return -EACCES; - spin_lock(&efivars_lock); + spin_lock(&efivars->lock); /* * Does this variable already exist? */ - list_for_each_entry_safe(search_efivar, n, &efivar_list, list) { + list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); strsize2 = utf8_strsize(del_var->VariableName, 1024); if (strsize1 == strsize2 && @@ -492,44 +489,34 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, } } if (!found) { - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EINVAL; } /* force the Attributes/DataSize to 0 to ensure deletion */ del_var->Attributes = 0; del_var->DataSize = 0; - status = efi.set_variable(del_var->VariableName, - &del_var->VendorGuid, - del_var->Attributes, - del_var->DataSize, - del_var->Data); + status = efivars->ops->set_variable(del_var->VariableName, + &del_var->VendorGuid, + del_var->Attributes, + del_var->DataSize, + del_var->Data); if (status != EFI_SUCCESS) { printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", status); - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); return -EIO; } list_del(&search_efivar->list); /* We need to release this lock before unregistering. */ - spin_unlock(&efivars_lock); + spin_unlock(&efivars->lock); efivar_unregister(search_efivar); /* It's dead Jim.... */ return count; } -static struct bin_attribute var_subsys_attr_new_var = { - .attr = {.name = "new_var", .mode = 0200}, - .write = efivar_create, -}; - -static struct bin_attribute var_subsys_attr_del_var = { - .attr = {.name = "del_var", .mode = 0200}, - .write = efivar_delete, -}; - /* * Let's not leave out systab information that snuck into * the efivars driver @@ -572,8 +559,6 @@ static struct attribute_group efi_subsys_attr_group = { .attrs = efi_subsys_attrs, }; - -static struct kset *vars_kset; static struct kobject *efi_kobj; /* @@ -582,13 +567,14 @@ static struct kobject *efi_kobj; * variable_name_size = number of bytes required to hold * variable_name (not counting the NULL * character at the end. - * efivars_lock is not held on entry or exit. + * efivars->lock is not held on entry or exit. * Returns 1 on failure, 0 on success */ static int -efivar_create_sysfs_entry(unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid) +efivar_create_sysfs_entry(struct efivars *efivars, + unsigned long variable_name_size, + efi_char16_t *variable_name, + efi_guid_t *vendor_guid) { int i, short_name_size = variable_name_size / sizeof(efi_char16_t) + 38; char *short_name; @@ -603,6 +589,7 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, return 1; } + new_efivar->efivars = efivars; memcpy(new_efivar->var.VariableName, variable_name, variable_name_size); memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t)); @@ -618,7 +605,7 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, *(short_name + strlen(short_name)) = '-'; efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); - new_efivar->kobj.kset = vars_kset; + new_efivar->kobj.kset = efivars->kset; i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL, "%s", short_name); if (i) { @@ -631,22 +618,95 @@ efivar_create_sysfs_entry(unsigned long variable_name_size, kfree(short_name); short_name = NULL; - spin_lock(&efivars_lock); - list_add(&new_efivar->list, &efivar_list); - spin_unlock(&efivars_lock); + spin_lock(&efivars->lock); + list_add(&new_efivar->list, &efivars->list); + spin_unlock(&efivars->lock); return 0; } -/* - * For now we register the efi subsystem with the firmware subsystem - * and the vars subsystem with the efi subsystem. In the future, it - * might make sense to split off the efi subsystem into its own - * driver, but for now only efivars will register with it, so just - * include it here. - */ -static int __init -efivars_init(void) +static int +create_efivars_bin_attributes(struct efivars *efivars) +{ + struct bin_attribute *attr; + int error; + + /* new_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attr->attr.name = "new_var"; + attr->attr.mode = 0200; + attr->write = efivar_create; + attr->private = efivars; + efivars->new_var = attr; + + /* del_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) { + error = -ENOMEM; + goto out_free; + } + attr->attr.name = "del_var"; + attr->attr.mode = 0200; + attr->write = efivar_delete; + attr->private = efivars; + efivars->del_var = attr; + + sysfs_bin_attr_init(efivars->new_var); + sysfs_bin_attr_init(efivars->del_var); + + /* Register */ + error = sysfs_create_bin_file(&efivars->kset->kobj, + efivars->new_var); + if (error) { + printk(KERN_ERR "efivars: unable to create new_var sysfs file" + " due to error %d\n", error); + goto out_free; + } + error = sysfs_create_bin_file(&efivars->kset->kobj, + efivars->del_var); + if (error) { + printk(KERN_ERR "efivars: unable to create del_var sysfs file" + " due to error %d\n", error); + sysfs_remove_bin_file(&efivars->kset->kobj, + efivars->new_var); + goto out_free; + } + + return 0; +out_free: + kfree(efivars->new_var); + efivars->new_var = NULL; + kfree(efivars->new_var); + efivars->new_var = NULL; + return error; +} + +void unregister_efivars(struct efivars *efivars) +{ + struct efivar_entry *entry, *n; + + list_for_each_entry_safe(entry, n, &efivars->list, list) { + spin_lock(&efivars->lock); + list_del(&entry->list); + spin_unlock(&efivars->lock); + efivar_unregister(entry); + } + if (efivars->new_var) + sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var); + if (efivars->del_var) + sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var); + kfree(efivars->new_var); + kfree(efivars->del_var); + kset_unregister(efivars->kset); +} +EXPORT_SYMBOL_GPL(unregister_efivars); + +int register_efivars(struct efivars *efivars, + const struct efivar_operations *ops, + struct kobject *parent_kobj) { efi_status_t status = EFI_NOT_FOUND; efi_guid_t vendor_guid; @@ -654,31 +714,21 @@ efivars_init(void) unsigned long variable_name_size = 1024; int error = 0; - if (!efi_enabled) - return -ENODEV; - variable_name = kzalloc(variable_name_size, GFP_KERNEL); if (!variable_name) { printk(KERN_ERR "efivars: Memory allocation failed.\n"); return -ENOMEM; } - printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, - EFIVARS_DATE); + spin_lock_init(&efivars->lock); + INIT_LIST_HEAD(&efivars->list); + efivars->ops = ops; - /* For now we'll register the efi directory at /sys/firmware/efi */ - efi_kobj = kobject_create_and_add("efi", firmware_kobj); - if (!efi_kobj) { - printk(KERN_ERR "efivars: Firmware registration failed.\n"); - error = -ENOMEM; - goto out_free; - } - - vars_kset = kset_create_and_add("vars", NULL, efi_kobj); - if (!vars_kset) { + efivars->kset = kset_create_and_add("vars", NULL, parent_kobj); + if (!efivars->kset) { printk(KERN_ERR "efivars: Subsystem registration failed.\n"); error = -ENOMEM; - goto out_firmware_unregister; + goto out; } /* @@ -689,14 +739,15 @@ efivars_init(void) do { variable_name_size = 1024; - status = efi.get_next_variable(&variable_name_size, + status = ops->get_next_variable(&variable_name_size, variable_name, &vendor_guid); switch (status) { case EFI_SUCCESS: - efivar_create_sysfs_entry(variable_name_size, - variable_name, - &vendor_guid); + efivar_create_sysfs_entry(efivars, + variable_name_size, + variable_name, + &vendor_guid); break; case EFI_NOT_FOUND: break; @@ -708,35 +759,60 @@ efivars_init(void) } } while (status != EFI_NOT_FOUND); - /* - * Now add attributes to allow creation of new vars - * and deletion of existing ones... - */ - error = sysfs_create_bin_file(&vars_kset->kobj, - &var_subsys_attr_new_var); - if (error) - printk(KERN_ERR "efivars: unable to create new_var sysfs file" - " due to error %d\n", error); - error = sysfs_create_bin_file(&vars_kset->kobj, - &var_subsys_attr_del_var); + error = create_efivars_bin_attributes(efivars); if (error) - printk(KERN_ERR "efivars: unable to create del_var sysfs file" - " due to error %d\n", error); + unregister_efivars(efivars); - /* Don't forget the systab entry */ - error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); - if (error) - printk(KERN_ERR "efivars: Sysfs attribute export failed with error %d.\n", error); - else - goto out_free; +out: + kfree(variable_name); - kset_unregister(vars_kset); + return error; +} +EXPORT_SYMBOL_GPL(register_efivars); -out_firmware_unregister: - kobject_put(efi_kobj); +static struct efivars __efivars; +static struct efivar_operations ops; -out_free: - kfree(variable_name); +/* + * For now we register the efi subsystem with the firmware subsystem + * and the vars subsystem with the efi subsystem. In the future, it + * might make sense to split off the efi subsystem into its own + * driver, but for now only efivars will register with it, so just + * include it here. + */ + +static int __init +efivars_init(void) +{ + int error = 0; + + printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, + EFIVARS_DATE); + + if (!efi_enabled) + return 0; + + /* For now we'll register the efi directory at /sys/firmware/efi */ + efi_kobj = kobject_create_and_add("efi", firmware_kobj); + if (!efi_kobj) { + printk(KERN_ERR "efivars: Firmware registration failed.\n"); + return -ENOMEM; + } + + ops.get_variable = efi.get_variable; + ops.set_variable = efi.set_variable; + ops.get_next_variable = efi.get_next_variable; + error = register_efivars(&__efivars, &ops, efi_kobj); + + /* Don't forget the systab entry */ + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); + if (error) { + printk(KERN_ERR + "efivars: Sysfs attribute export failed with error %d.\n", + error); + unregister_efivars(&__efivars); + kobject_put(efi_kobj); + } return error; } @@ -744,16 +820,7 @@ out_free: static void __exit efivars_exit(void) { - struct efivar_entry *entry, *n; - - list_for_each_entry_safe(entry, n, &efivar_list, list) { - spin_lock(&efivars_lock); - list_del(&entry->list); - spin_unlock(&efivars_lock); - efivar_unregister(entry); - } - - kset_unregister(vars_kset); + unregister_efivars(&__efivars); kobject_put(efi_kobj); } |