Peter, I don't see this patch working in my system. +static inline int esrt_table_exists(void) { + if (!efi_enabled(EFI_CONFIG_TABLES)) + return 0; + if (efi.esrt == EFI_INVALID_TABLE_ADDR) + return 0; + return 1; +} Validation is failing because of efi.esrt == EFI_INVALID_TABLE_ADDR What is the dependency to make this patch work ? how it will get valid address for esrt ? Or soothing else is required in this patch ? -Param -----Original Message----- From: linux-efi-owner@xxxxxxxxxxxxxxx [mailto:linux-efi-owner@xxxxxxxxxxxxxxx] On Behalf Of Peter Jones Sent: Friday, December 12, 2014 1:52 AM To: linux-efi@xxxxxxxxxxxxxxx Cc: Peter Jones Subject: [RFC PATCH] Add esrt support. Add sysfs files for EFI System Resource Table under /sys/firmware/efi/esrt and for each EFI System Resource Entry under entries/ as a subdir. v2 with suggestions from bpetkov. v3 with me remembering checkpatch. v4 without me typing struct decls completely wrong somehow. Signed-off-by: Peter Jones <pjones@xxxxxxxxxx> --- drivers/firmware/efi/Makefile | 2 +- drivers/firmware/efi/efi.c | 46 ++++- drivers/firmware/efi/esrt.c | 393 ++++++++++++++++++++++++++++++++++++++++++ include/linux/efi.h | 6 + 4 files changed, 445 insertions(+), 2 deletions(-) create mode 100644 drivers/firmware/efi/esrt.c diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index aef6a95..0d61089 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -1,7 +1,7 @@ # # Makefile for linux kernel # -obj-$(CONFIG_EFI) += efi.o vars.o reboot.o +obj-$(CONFIG_EFI) += efi.o esrt.o vars.o reboot.o obj-$(CONFIG_EFI_VARS) += efivars.o obj-$(CONFIG_EFI_VARS_PSTORE) += efi-pstore.o obj-$(CONFIG_UEFI_CPER) += cper.o diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8590099..68002d8 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -38,6 +38,7 @@ struct efi __read_mostly efi = { .fw_vendor = EFI_INVALID_TABLE_ADDR, .runtime = EFI_INVALID_TABLE_ADDR, .config_table = EFI_INVALID_TABLE_ADDR, + .esrt = EFI_INVALID_TABLE_ADDR, }; EXPORT_SYMBOL(efi); @@ -63,7 +64,7 @@ static int __init parse_efi_cmdline(char *str) } early_param("efi", parse_efi_cmdline); -static struct kobject *efi_kobj; +struct kobject *efi_kobj; static struct kobject *efivars_kobj; /* @@ -92,6 +93,8 @@ static ssize_t systab_show(struct kobject *kobj, str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); if (efi.uga != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "UGA=0x%lx\n", efi.uga); + if (efi.esrt != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "ESRT=0x%lx\n", efi.esrt); return str - buf; } @@ -220,6 +223,46 @@ err_put: subsys_initcall(efisubsys_init); +/* + * Given a physicall address, determine if it exists within an EFI +Memory Map + * entry, and if so, how much of that map exists at a higher address. +That + * is, if this is the address of something in an EFI map, what's the +highest + * address at which it's likely to end. + */ +u64 efi_mem_max_reasonable_size(u64 phys_addr) { + struct efi_memory_map *map = efi.memmap; + void *p, *e; + + if (!map) + return -1; + if (WARN_ON(!map->phys_map)) + return -1; + if (WARN_ON(map->nr_map == 0) || WARN_ON(map->desc_size == 0)) + return -1; + + e = map->phys_map + map->nr_map * map->desc_size; + for (p = map->phys_map; p < e; p += map->desc_size) { + /* + * If a driver calls this after efi_free_boot_services, + * ->map will be NULL. + * So just always get our own virtual map on the CPU. + */ + efi_memory_desc_t *md = phys_to_virt((phys_addr_t)p); + u64 size = md->num_pages << EFI_PAGE_SHIFT; + u64 end = md->phys_addr + size; + + if (!(md->attribute & EFI_MEMORY_RUNTIME) && + md->type != EFI_BOOT_SERVICES_CODE && + md->type != EFI_BOOT_SERVICES_DATA) + continue; + if (!md->virt_addr) + continue; + if (phys_addr >= md->phys_addr && phys_addr < end) + return end - phys_addr; + } + return -1; +} /* * We can't ioremap data in EFI boot services RAM, because we've already mapped @@ -261,6 +304,7 @@ static __initdata efi_config_table_type_t common_tables[] = { {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab}, {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios}, {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga}, + {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt}, {NULL_GUID, NULL, NULL}, }; diff --git a/drivers/firmware/efi/esrt.c b/drivers/firmware/efi/esrt.c new file mode 100644 index 0000000..a58065b --- /dev/null +++ b/drivers/firmware/efi/esrt.c @@ -0,0 +1,393 @@ +/* + * esrt.c + * + * This module exports EFI System Resource Table (ESRT) entries into +userspace + * through the sysfs file system. The ESRT provides a read-only catalog +of + * system components for which the system accepts firmware upgrades via +UEFI's + * "Capsule Update" feature. This module allows userland utilities to +evaluate + * what firmware updates can be applied to this system, and potentially +arrange + * for those updates to occur. + * + * Data is currently found below /sys/firmware/efi/esrt/... + */ +#define pr_fmt(fmt) "esrt: " fmt + +#include <linux/capability.h> +#include <linux/device.h> +#include <linux/efi.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/kobject.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/types.h> + +struct efi_system_resource_entry { + efi_guid_t fw_class; + u32 fw_type; + u32 fw_version; + u32 lowest_supported_fw_version; + u32 capsule_flags; + u32 last_attempt_version; + u32 last_attempt_status; +}; + +/* + * _count and _version are what they seem like. _max is actually just + * accounting info for the firmware when creating the table; it should +never + * have been exposed to us. To wit, the spec says: + * The maximum number of resource array entries that can be within the + * table without reallocating the table, must not be zero. + * Since there's no guidance about what that means in terms of memory +layout, + * it means nothing to us. + */ +struct efi_system_resource_table { + u32 fw_resource_count; + u32 fw_resource_count_max; + u64 fw_resource_version; + struct efi_system_resource_entry entries[]; }; + +static struct efi_system_resource_table *esrt; + +struct esre_entry { + struct efi_system_resource_entry *esre; + + struct kobject kobj; + struct list_head list; +}; + +/* global list of esre_entry. */ +static LIST_HEAD(entry_list); + +/* entry attribute */ +struct esre_attribute { + struct attribute attr; + ssize_t (*show)(struct esre_entry *entry, char *buf); + ssize_t (*store)(struct esre_entry *entry, + const char *buf, size_t count); +}; + +static struct esre_entry *to_entry(struct kobject *kobj) { + return container_of(kobj, struct esre_entry, kobj); } + +static struct esre_attribute *to_attr(struct attribute *attr) { + return container_of(attr, struct esre_attribute, attr); } + +static ssize_t esre_attr_show(struct kobject *kobj, + struct attribute *_attr, char *buf) { + struct esre_entry *entry = to_entry(kobj); + struct esre_attribute *attr = to_attr(_attr); + + /* Don't tell normal users what firmware versions we've got... */ + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + return attr->show(entry, buf); +} + +static const struct sysfs_ops esre_attr_ops = { + .show = esre_attr_show, +}; + +/* Generic ESRT Entry ("ESRE") support. */ static ssize_t +esre_fw_class_show(struct esre_entry *entry, char *buf) { + char *str = buf; + + efi_guid_unparse(&entry->esre->fw_class, str); + str += strlen(str); + str += sprintf(str, "\n"); + + return str - buf; +} + +static struct esre_attribute esre_fw_class = __ATTR(fw_class, 0400, + esre_fw_class_show, NULL); + +#define esre_attr_decl(name, size, fmt) \ static ssize_t +esre_##name##_show(struct esre_entry *entry, char *buf)\ { \ + return sprintf(buf, fmt "\n", le##size##_to_cpu(entry->esre->name)); \ +} \ \ static struct esre_attribute esre_##name = __ATTR(name, 0400, \ + esre_##name##_show, NULL) + +esre_attr_decl(fw_type, 32, "%u"); +esre_attr_decl(fw_version, 32, "%u"); +esre_attr_decl(lowest_supported_fw_version, 32, "%u"); +esre_attr_decl(capsule_flags, 32, "0x%x"); +esre_attr_decl(last_attempt_version, 32, "%u"); +esre_attr_decl(last_attempt_status, 32, "%u"); + +static struct attribute *esre_attrs[] = { + &esre_fw_class.attr, + &esre_fw_type.attr, + &esre_fw_version.attr, + &esre_lowest_supported_fw_version.attr, + &esre_capsule_flags.attr, + &esre_last_attempt_version.attr, + &esre_last_attempt_status.attr, + NULL +}; + +static void esre_release(struct kobject *kobj) { + struct esre_entry *entry = to_entry(kobj); + + list_del(&entry->list); + kfree(entry); +} + +static struct kobj_type esre_ktype = { + .release = esre_release, + .sysfs_ops = &esre_attr_ops, + .default_attrs = esre_attrs, +}; + +static struct kobject *esrt_kobj; +static struct kset *esrt_kset; + +static int esre_create_sysfs_entry(struct efi_system_resource_entry +*esre) { + int rc; + struct esre_entry *entry; + char name[EFI_VARIABLE_GUID_LEN + 1]; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + efi_guid_unparse(&esre->fw_class, name); + + entry->esre = esre; + entry->kobj.kset = esrt_kset; + rc = kobject_init_and_add(&entry->kobj, &esre_ktype, NULL, + "%s", name); + if (rc) { + kfree(entry); + return rc; + } + + list_add_tail(&entry->list, &entry_list); + return 0; +} + +/* support for displaying ESRT fields at the top level */ #define +esrt_attr_decl(name, size, fmt) \ static ssize_t +esrt_##name##_show(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf)\ { \ + return sprintf(buf, fmt "\n", le##size##_to_cpu(esrt->name)); \ } \ \ +static struct kobj_attribute esrt_##name = __ATTR(name, 0400, \ + esrt_##name##_show, NULL) + +esrt_attr_decl(fw_resource_count, 32, "%u"); +esrt_attr_decl(fw_resource_count_max, 32, "%u"); +esrt_attr_decl(fw_resource_version, 64, "%llu"); + +static struct attribute *esrt_attrs[] = { + &esrt_fw_resource_count.attr, + &esrt_fw_resource_count_max.attr, + &esrt_fw_resource_version.attr, + NULL, +}; + +static inline int esrt_table_exists(void) { + if (!efi_enabled(EFI_CONFIG_TABLES)) + return 0; + if (efi.esrt == EFI_INVALID_TABLE_ADDR) + return 0; + return 1; +} + +static umode_t esrt_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + if (!esrt_table_exists()) + return 0; + return attr->mode; +} + +static struct attribute_group esrt_attr_group = { + .attrs = esrt_attrs, + .is_visible = esrt_attr_is_visible, +}; + +/* + * ioremap the table, copy it to kmalloced pages, and unmap it. + */ +static int esrt_duplicate_pages(void) +{ + struct efi_system_resource_table *tmpesrt; + struct efi_system_resource_entry *entries; + size_t size, max; + int err = -EINVAL; + + if (!esrt_table_exists()) + return err; + + max = efi_mem_max_reasonable_size(efi.esrt); + if (max < 0) { + pr_err("ESRT header is not in the memory map.\n"); + return err; + } + size = sizeof(*esrt); + + if (max < size) { + pr_err("ESRT header doen't fit on single memory map entry.\n"); + return err; + } + + tmpesrt = ioremap(efi.esrt, size); + if (!tmpesrt) { + pr_err("ioremap failed.\n"); + return -ENOMEM; + } + + if (tmpesrt->fw_resource_count > 0 && max - size < sizeof(*entries)) { + pr_err("ESRT memory map entry can only hold the header.\n"); + goto err_iounmap; + } + + /* + * The format doesn't really give us any boundary to test here, + * so I'm making up 128 as the max number of individually updatable + * components we support. + * 128 should be pretty excessive, but there's still some chance + * somebody will do that someday and we'll need to raise this. + */ + if (tmpesrt->fw_resource_count > 128) { + pr_err("ESRT says fw_resource_count has very large value %d.\n", + tmpesrt->fw_resource_count); + goto err_iounmap; + } + + /* + * We know it can't be larger than N * sizeof() here, and N is limited + * by the previous test to a small number, so there's no overflow. + */ + size += tmpesrt->fw_resource_count * sizeof(*entries); + if (max < size) { + pr_err("ESRT does not fit on single memory map entry.\n"); + goto err_iounmap; + } + + esrt = kmalloc(size, GFP_KERNEL); + if (!esrt) { + err = -ENOMEM; + goto err_iounmap; + } + + memcpy(esrt, tmpesrt, size); + err = 0; +err_iounmap: + iounmap(tmpesrt); + return err; +} + +static int register_entries(void) +{ + struct efi_system_resource_entry *entries = esrt->entries; + int i, rc; + + if (!esrt_table_exists()) + return 0; + + for (i = 0; i < le32_to_cpu(esrt->fw_resource_count); i++) { + rc = esre_create_sysfs_entry(&entries[i]); + if (rc < 0) { + pr_err("ESRT entry creation failed with error %d.\n", + rc); + return rc; + } + } + return 0; +} + +static void cleanup_entry_list(void) +{ + struct esre_entry *entry, *next; + + list_for_each_entry_safe(entry, next, &entry_list, list) { + kobject_put(&entry->kobj); + } +} + +static int __init esrt_sysfs_init(void) { + int error; + + error = esrt_duplicate_pages(); + if (error) + return error; + + esrt_kobj = kobject_create_and_add("esrt", efi_kobj); + if (!esrt_kobj) { + pr_err("Firmware table registration failed.\n"); + error = -ENOMEM; + goto err; + } + + error = sysfs_create_group(esrt_kobj, &esrt_attr_group); + if (error) { + pr_err("Sysfs attribute export failed with error %d.\n", + error); + goto err_remove_esrt; + } + + esrt_kset = kset_create_and_add("entries", NULL, esrt_kobj); + if (!esrt_kset) { + pr_err("kset creation failed.\n"); + error = -ENOMEM; + goto err_remove_group; + } + + error = register_entries(); + if (error) + goto err_cleanup_list; + + pr_debug("esrt-sysfs: loaded.\n"); + + return 0; +err_cleanup_list: + cleanup_entry_list(); + kset_unregister(esrt_kset); +err_remove_group: + sysfs_remove_group(esrt_kobj, &esrt_attr_group); +err_remove_esrt: + kobject_put(esrt_kobj); +err: + kfree(esrt); + esrt = NULL; + return error; +} + +static void __exit esrt_sysfs_exit(void) { + pr_debug("esrt-sysfs: unloading.\n"); + cleanup_entry_list(); + kset_unregister(esrt_kset); + sysfs_remove_group(esrt_kobj, &esrt_attr_group); + kfree(esrt); + esrt = NULL; + kobject_del(esrt_kobj); + kobject_put(esrt_kobj); +} + +module_init(esrt_sysfs_init); +module_exit(esrt_sysfs_exit); + +MODULE_AUTHOR("Peter Jones <pjones@xxxxxxxxxx>"); +MODULE_DESCRIPTION("EFI System Resource Table support"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/efi.h b/include/linux/efi.h index 0949f9c..5b663a7 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -562,6 +562,9 @@ void efi_native_runtime_setup(void); #define UV_SYSTEM_TABLE_GUID \ EFI_GUID( 0x3b13a7d4, 0x633e, 0x11dd, 0x93, 0xec, 0xda, 0x25, 0x56, 0xd8, 0x95, 0x93 ) +#define EFI_SYSTEM_RESOURCE_TABLE_GUID \ + EFI_GUID( 0xb122a263, 0x3661, 0x4f68, 0x99, 0x29, 0x78, 0xf8, +0xb0, 0xd6, 0x21, 0x80 ) + #define LINUX_EFI_CRASH_GUID \ EFI_GUID( 0xcfc8fc79, 0xbe2e, 0x4ddc, 0x97, 0xf0, 0x9f, 0x98, 0xbf, 0xe2, 0x98, 0xa0 ) @@ -819,6 +822,7 @@ extern struct efi { unsigned long fw_vendor; /* fw_vendor */ unsigned long runtime; /* runtime table */ unsigned long config_table; /* config tables */ + unsigned long esrt; /* EFI System Resource Table */ efi_get_time_t *get_time; efi_set_time_t *set_time; efi_get_wakeup_time_t *get_wakeup_time; @@ -875,6 +879,7 @@ extern u64 efi_get_iobase (void); extern u32 efi_mem_type (unsigned long phys_addr); extern u64 efi_mem_attributes (unsigned long phys_addr); extern u64 efi_mem_attribute (unsigned long phys_addr, unsigned long size); +extern u64 efi_mem_max_reasonable_size(u64 phys_addr); extern int __init efi_uart_console_only (void); extern void efi_initialize_iomem_resources(struct resource *code_resource, struct resource *data_resource, struct resource *bss_resource); @@ -882,6 +887,7 @@ extern void efi_get_time(struct timespec *now); extern void efi_reserve_boot_services(void); extern int efi_get_fdt_params(struct efi_fdt_params *params, int verbose); extern struct efi_memory_map memmap; +extern struct kobject *efi_kobj; extern int efi_reboot_quirk_mode; extern bool efi_poweroff_required(void); -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html