// SPDX-License-Identifier: GPL-2.0-only
/*
 * efi.c - EFI subsystem
 *
 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
 *
 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
 * allowing the efivarfs to be mounted or the efivars module to be loaded.
 * The existance of /sys/firmware/efi may also be used by userspace to
 * determine that the system supports EFI.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/efi.h>
#include <linux/of.h>
#include <linux/initrd.h>
#include <linux/io.h>
#include <linux/kexec.h>
#include <linux/platform_device.h>
#include <linux/random.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/ucs2_string.h>
#include <linux/memblock.h>
#include <linux/security.h>
#include <linux/notifier.h>

#include <asm/early_ioremap.h>

struct efi __read_mostly efi = {
        .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
        .acpi                   = EFI_INVALID_TABLE_ADDR,
        .acpi20                 = EFI_INVALID_TABLE_ADDR,
        .smbios                 = EFI_INVALID_TABLE_ADDR,
        .smbios3                = EFI_INVALID_TABLE_ADDR,
        .esrt                   = EFI_INVALID_TABLE_ADDR,
        .tpm_log                = EFI_INVALID_TABLE_ADDR,
        .tpm_final_log          = EFI_INVALID_TABLE_ADDR,
        .ovmf_debug_log         = EFI_INVALID_TABLE_ADDR,
#ifdef CONFIG_LOAD_UEFI_KEYS
        .mokvar_table           = EFI_INVALID_TABLE_ADDR,
#endif
#ifdef CONFIG_EFI_COCO_SECRET
        .coco_secret            = EFI_INVALID_TABLE_ADDR,
#endif
#ifdef CONFIG_UNACCEPTED_MEMORY
        .unaccepted             = EFI_INVALID_TABLE_ADDR,
#endif
};
EXPORT_SYMBOL(efi);

unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;

extern unsigned long primary_display_table;

struct mm_struct efi_mm = {
        .mm_mt                  = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
        .mm_users               = ATOMIC_INIT(2),
        .mm_count               = ATOMIC_INIT(1),
        .write_protect_seq      = SEQCNT_ZERO(efi_mm.write_protect_seq),
        MMAP_LOCK_INITIALIZER(efi_mm)
        .page_table_lock        = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
        .mmlist                 = LIST_HEAD_INIT(efi_mm.mmlist),
#ifdef CONFIG_SCHED_MM_CID
        .mm_cid.lock            = __RAW_SPIN_LOCK_UNLOCKED(efi_mm.mm_cid.lock),
#endif
        .flexible_array         = MM_STRUCT_FLEXIBLE_ARRAY_INIT,
};

struct workqueue_struct *efi_rts_wq;

static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
static int __init setup_noefi(char *arg)
{
        disable_runtime = true;
        return 0;
}
early_param("noefi", setup_noefi);

bool efi_runtime_disabled(void)
{
        return disable_runtime;
}

bool __pure __efi_soft_reserve_enabled(void)
{
        return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
}

static int __init parse_efi_cmdline(char *str)
{
        if (!str) {
                pr_warn("need at least one option\n");
                return -EINVAL;
        }

        if (parse_option_str(str, "debug"))
                set_bit(EFI_DBG, &efi.flags);

        if (parse_option_str(str, "noruntime"))
                disable_runtime = true;

        if (parse_option_str(str, "runtime"))
                disable_runtime = false;

        if (parse_option_str(str, "nosoftreserve"))
                set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);

        return 0;
}
early_param("efi", parse_efi_cmdline);

struct kobject *efi_kobj;

/*
 * Let's not leave out systab information that snuck into
 * the efivars driver
 * Note, do not add more fields in systab sysfs file as it breaks sysfs
 * one value per file rule!
 */
static ssize_t systab_show(struct kobject *kobj,
                           struct kobj_attribute *attr, char *buf)
{
        char *str = buf;

        if (!kobj || !buf)
                return -EINVAL;

        if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
                str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
        if (efi.acpi != EFI_INVALID_TABLE_ADDR)
                str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
        /*
         * If both SMBIOS and SMBIOS3 entry points are implemented, the
         * SMBIOS3 entry point shall be preferred, so we list it first to
         * let applications stop parsing after the first match.
         */
        if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
                str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
        if (efi.smbios != EFI_INVALID_TABLE_ADDR)
                str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);

        return str - buf;
}

static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);

static ssize_t fw_platform_size_show(struct kobject *kobj,
                                     struct kobj_attribute *attr, char *buf)
{
        return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
}

extern __weak struct kobj_attribute efi_attr_fw_vendor;
extern __weak struct kobj_attribute efi_attr_runtime;
extern __weak struct kobj_attribute efi_attr_config_table;
static struct kobj_attribute efi_attr_fw_platform_size =
        __ATTR_RO(fw_platform_size);

static struct attribute *efi_subsys_attrs[] = {
        &efi_attr_systab.attr,
        &efi_attr_fw_platform_size.attr,
        &efi_attr_fw_vendor.attr,
        &efi_attr_runtime.attr,
        &efi_attr_config_table.attr,
        NULL,
};

umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
                                   int n)
{
        return attr->mode;
}

static const struct attribute_group efi_subsys_attr_group = {
        .attrs = efi_subsys_attrs,
        .is_visible = efi_attr_is_visible,
};

struct blocking_notifier_head efivar_ops_nh;
EXPORT_SYMBOL_GPL(efivar_ops_nh);

static struct efivars generic_efivars;
static struct efivar_operations generic_ops;

static bool generic_ops_supported(void)
{
        unsigned long name_size;
        efi_status_t status;
        efi_char16_t name;
        efi_guid_t guid;

        name_size = sizeof(name);

        if (!efi.get_next_variable)
                return false;
        status = efi.get_next_variable(&name_size, &name, &guid);
        if (status == EFI_UNSUPPORTED)
                return false;

        return true;
}

static int generic_ops_register(void)
{
        if (!generic_ops_supported())
                return 0;

        generic_ops.get_variable = efi.get_variable;
        generic_ops.get_next_variable = efi.get_next_variable;
        generic_ops.query_variable_store = efi_query_variable_store;
        generic_ops.query_variable_info = efi.query_variable_info;

        if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
                generic_ops.set_variable = efi.set_variable;
                generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
        }
        return efivars_register(&generic_efivars, &generic_ops);
}

static void generic_ops_unregister(void)
{
        if (!generic_ops.get_variable)
                return;

        efivars_unregister(&generic_efivars);
}

void efivars_generic_ops_register(void)
{
        generic_ops_register();
}
EXPORT_SYMBOL_GPL(efivars_generic_ops_register);

void efivars_generic_ops_unregister(void)
{
        generic_ops_unregister();
}
EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister);

#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
#define EFIVAR_SSDT_NAME_MAX    16UL
static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
static int __init efivar_ssdt_setup(char *str)
{
        int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);

        if (ret)
                return ret;

        if (strlen(str) < sizeof(efivar_ssdt))
                memcpy(efivar_ssdt, str, strlen(str));
        else
                pr_warn("efivar_ssdt: name too long: %s\n", str);
        return 1;
}
__setup("efivar_ssdt=", efivar_ssdt_setup);

static __init int efivar_ssdt_load(void)
{
        unsigned long name_size = 256;
        efi_char16_t *name = NULL;
        efi_status_t status;
        efi_guid_t guid;
        int ret = 0;

        if (!efivar_ssdt[0])
                return 0;

        name = kzalloc(name_size, GFP_KERNEL);
        if (!name)
                return -ENOMEM;

        for (;;) {
                char utf8_name[EFIVAR_SSDT_NAME_MAX];
                unsigned long data_size = 0;
                void *data;
                int limit;

                status = efi.get_next_variable(&name_size, name, &guid);
                if (status == EFI_NOT_FOUND) {
                        break;
                } else if (status == EFI_BUFFER_TOO_SMALL) {
                        efi_char16_t *name_tmp =
                                krealloc(name, name_size, GFP_KERNEL);
                        if (!name_tmp) {
                                ret = -ENOMEM;
                                goto out;
                        }
                        name = name_tmp;
                        continue;
                }

                limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
                ucs2_as_utf8(utf8_name, name, limit - 1);
                if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
                        continue;

                pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);

                status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
                if (status != EFI_BUFFER_TOO_SMALL || !data_size) {
                        ret = -EIO;
                        goto out;
                }

                data = kmalloc(data_size, GFP_KERNEL);
                if (!data) {
                        ret = -ENOMEM;
                        goto out;
                }

                status = efi.get_variable(name, &guid, NULL, &data_size, data);
                if (status == EFI_SUCCESS) {
                        acpi_status acpi_ret = acpi_load_table(data, NULL);
                        if (ACPI_FAILURE(acpi_ret)) {
                                pr_err("efivar_ssdt: failed to load table: %u\n",
                                       acpi_ret);
                        } else {
                                /*
                                 * The @data will be in use by ACPI engine,
                                 * do not free it!
                                 */
                                continue;
                        }
                } else {
                        pr_err("efivar_ssdt: failed to get var data: 0x%lx\n", status);
                }
                kfree(data);
        }
out:
        kfree(name);
        return ret;
}
#else
static inline int efivar_ssdt_load(void) { return 0; }
#endif

#ifdef CONFIG_DEBUG_FS

#define EFI_DEBUGFS_MAX_BLOBS 32

static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];

static void __init efi_debugfs_init(void)
{
        struct dentry *efi_debugfs;
        efi_memory_desc_t *md;
        char name[32];
        int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
        int i = 0;

        efi_debugfs = debugfs_create_dir("efi", NULL);
        if (IS_ERR(efi_debugfs))
                return;

        for_each_efi_memory_desc(md) {
                switch (md->type) {
                case EFI_BOOT_SERVICES_CODE:
                        snprintf(name, sizeof(name), "boot_services_code%d",
                                 type_count[md->type]++);
                        break;
                case EFI_BOOT_SERVICES_DATA:
                        snprintf(name, sizeof(name), "boot_services_data%d",
                                 type_count[md->type]++);
                        break;
                default:
                        continue;
                }

                if (i >= EFI_DEBUGFS_MAX_BLOBS) {
                        pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
                                EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
                        break;
                }

                debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
                debugfs_blob[i].data = memremap(md->phys_addr,
                                                debugfs_blob[i].size,
                                                MEMREMAP_WB);
                if (!debugfs_blob[i].data)
                        continue;

                debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
                i++;
        }
}
#else
static inline void efi_debugfs_init(void) {}
#endif

static int __init efipostcore_init(void)
{
        if (!efi_enabled(EFI_RUNTIME_SERVICES))
                efi.runtime_supported_mask = 0;

        if (efi.runtime_supported_mask) {
                /*
                 * Since we process only one efi_runtime_service() at a time, an
                 * ordered workqueue (which creates only one execution context)
                 * should suffice for all our needs.
                 */
                efi_rts_wq = alloc_ordered_workqueue("efi_runtime", WQ_SYSFS);
                if (!efi_rts_wq) {
                        pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
                        clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
                        efi.runtime_supported_mask = 0;
                }
        }
        return 0;
}
postcore_initcall(efipostcore_init);

/*
 * We register the efi subsystem with the firmware subsystem and the
 * efivars subsystem with the efi subsystem, if the system was booted with
 * EFI.
 */
static int __init efisubsys_init(void)
{
        int error;

        if (!efi_enabled(EFI_BOOT))
                return 0;

        if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
                platform_device_register_simple("rtc-efi", 0, NULL, 0);

        /* We register the efi directory at /sys/firmware/efi */
        efi_kobj = kobject_create_and_add("efi", firmware_kobj);
        if (!efi_kobj) {
                pr_err("efi: Firmware registration failed.\n");
                error = -ENOMEM;
                goto err_destroy_wq;
        }

        if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
                                      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
                error = generic_ops_register();
                if (error)
                        goto err_put;
                error = efivar_ssdt_load();
                if (error)
                        pr_err("efi: failed to load SSDT, error %d.\n", error);
                platform_device_register_simple("efivars", 0, NULL, 0);
        }

        BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh);

        error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
        if (error) {
                pr_err("efi: Sysfs attribute export failed with error %d.\n",
                       error);
                goto err_unregister;
        }

        /* and the standard mountpoint for efivarfs */
        error = sysfs_create_mount_point(efi_kobj, "efivars");
        if (error) {
                pr_err("efivars: Subsystem registration failed.\n");
                goto err_remove_group;
        }

        if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
                efi_debugfs_init();

#ifdef CONFIG_EFI_COCO_SECRET
        if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
                platform_device_register_simple("efi_secret", 0, NULL, 0);
#endif

        if (IS_ENABLED(CONFIG_OVMF_DEBUG_LOG) &&
            efi.ovmf_debug_log != EFI_INVALID_TABLE_ADDR)
                ovmf_log_probe(efi.ovmf_debug_log);

        return 0;

err_remove_group:
        sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
err_unregister:
        if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
                                      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
                generic_ops_unregister();
err_put:
        kobject_put(efi_kobj);
        efi_kobj = NULL;
err_destroy_wq:
        if (efi_rts_wq)
                destroy_workqueue(efi_rts_wq);

        return error;
}

subsys_initcall(efisubsys_init);

void __init efi_find_mirror(void)
{
        efi_memory_desc_t *md;
        u64 mirror_size = 0, total_size = 0;

        if (!efi_enabled(EFI_MEMMAP))
                return;

        for_each_efi_memory_desc(md) {
                unsigned long long start = md->phys_addr;
                unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;

                total_size += size;
                if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
                        memblock_mark_mirror(start, size);
                        mirror_size += size;
                }
        }
        if (mirror_size)
                pr_info("Memory: %lldM/%lldM mirrored memory\n",
                        mirror_size>>20, total_size>>20);
}

/*
 * Find the efi memory descriptor for a given physical address.  Given a
 * physical address, determine if it exists within an EFI Memory Map entry,
 * and if so, populate the supplied memory descriptor with the appropriate
 * data.
 */
int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
{
        efi_memory_desc_t *md;

        if (!efi_enabled(EFI_MEMMAP)) {
                pr_err_once("EFI_MEMMAP is not enabled.\n");
                return -EINVAL;
        }

        if (!out_md) {
                pr_err_once("out_md is null.\n");
                return -EINVAL;
        }

        for_each_efi_memory_desc(md) {
                u64 size;
                u64 end;

                /* skip bogus entries (including empty ones) */
                if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
                    (md->num_pages <= 0) ||
                    (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
                        continue;

                size = md->num_pages << EFI_PAGE_SHIFT;
                end = md->phys_addr + size;
                if (phys_addr >= md->phys_addr && phys_addr < end) {
                        memcpy(out_md, md, sizeof(*out_md));
                        return 0;
                }
        }
        return -ENOENT;
}

extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
        __weak __alias(__efi_mem_desc_lookup);
EXPORT_SYMBOL_GPL(efi_mem_desc_lookup);

/*
 * Calculate the highest address of an efi memory descriptor.
 */
u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
{
        u64 size = md->num_pages << EFI_PAGE_SHIFT;
        u64 end = md->phys_addr + size;
        return end;
}

void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}

/**
 * efi_mem_reserve - Reserve an EFI memory region
 * @addr: Physical address to reserve
 * @size: Size of reservation
 *
 * Mark a region as reserved from general kernel allocation and
 * prevent it being released by efi_free_boot_services().
 *
 * This function should be called drivers once they've parsed EFI
 * configuration tables to figure out where their data lives, e.g.
 * efi_esrt_init().
 */
void __init efi_mem_reserve(phys_addr_t addr, u64 size)
{
        /* efi_mem_reserve() does not work under Xen */
        if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
                return;

        if (!memblock_is_region_reserved(addr, size))
                memblock_reserve_kern(addr, size);
        else
                memblock_reserved_mark_kern(addr, size);

        /*
         * Some architectures (x86) reserve all boot services ranges
         * until efi_free_boot_services() because of buggy firmware
         * implementations. This means the above memblock_reserve() is
         * superfluous on x86 and instead what it needs to do is
         * ensure the @start, @size is not freed.
         */
        efi_arch_mem_reserve(addr, size);
}

static const efi_config_table_type_t common_tables[] __initconst = {
        {ACPI_20_TABLE_GUID,                    &efi.acpi20,            "ACPI 2.0"      },
        {ACPI_TABLE_GUID,                       &efi.acpi,              "ACPI"          },
        {SMBIOS_TABLE_GUID,                     &efi.smbios,            "SMBIOS"        },
        {SMBIOS3_TABLE_GUID,                    &efi.smbios3,           "SMBIOS 3.0"    },
        {EFI_SYSTEM_RESOURCE_TABLE_GUID,        &efi.esrt,              "ESRT"          },
        {EFI_MEMORY_ATTRIBUTES_TABLE_GUID,      &efi_mem_attr_table,    "MEMATTR"       },
        {LINUX_EFI_RANDOM_SEED_TABLE_GUID,      &efi_rng_seed,          "RNG"           },
        {LINUX_EFI_TPM_EVENT_LOG_GUID,          &efi.tpm_log,           "TPMEventLog"   },
        {EFI_TCG2_FINAL_EVENTS_TABLE_GUID,      &efi.tpm_final_log,     "TPMFinalLog"   },
        {EFI_CC_FINAL_EVENTS_TABLE_GUID,        &efi.tpm_final_log,     "CCFinalLog"    },
        {LINUX_EFI_MEMRESERVE_TABLE_GUID,       &mem_reserve,           "MEMRESERVE"    },
        {LINUX_EFI_INITRD_MEDIA_GUID,           &initrd,                "INITRD"        },
        {EFI_RT_PROPERTIES_TABLE_GUID,          &rt_prop,               "RTPROP"        },
#ifdef CONFIG_OVMF_DEBUG_LOG
        {OVMF_MEMORY_LOG_TABLE_GUID,            &efi.ovmf_debug_log,    "OvmfDebugLog"  },
#endif
#ifdef CONFIG_EFI_RCI2_TABLE
        {DELLEMC_EFI_RCI2_TABLE_GUID,           &rci2_table_phys                        },
#endif
#ifdef CONFIG_LOAD_UEFI_KEYS
        {LINUX_EFI_MOK_VARIABLE_TABLE_GUID,     &efi.mokvar_table,      "MOKvar"        },
#endif
#ifdef CONFIG_EFI_COCO_SECRET
        {LINUX_EFI_COCO_SECRET_AREA_GUID,       &efi.coco_secret,       "CocoSecret"    },
#endif
#ifdef CONFIG_UNACCEPTED_MEMORY
        {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID,   &efi.unaccepted,        "Unaccepted"    },
#endif
#ifdef CONFIG_EFI_GENERIC_STUB
        {LINUX_EFI_PRIMARY_DISPLAY_TABLE_GUID,  &primary_display_table                  },
#endif
        {},
};

static __init int match_config_table(const efi_guid_t *guid,
                                     unsigned long table,
                                     const efi_config_table_type_t *table_types)
{
        int i;

        for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
                if (efi_guidcmp(*guid, table_types[i].guid))
                        continue;

                if (!efi_config_table_is_usable(guid, table)) {
                        if (table_types[i].name[0])
                                pr_cont("(%s=0x%lx unusable) ",
                                        table_types[i].name, table);
                        return 1;
                }

                *(table_types[i].ptr) = table;
                if (table_types[i].name[0])
                        pr_cont("%s=0x%lx ", table_types[i].name, table);
                return 1;
        }

        return 0;
}

/**
 * reserve_unaccepted - Map and reserve unaccepted configuration table
 * @unaccepted: Pointer to unaccepted memory table
 *
 * memblock_add() makes sure that the table is mapped in direct mapping. During
 * normal boot it happens automatically because the table is allocated from
 * usable memory. But during crashkernel boot only memory specifically reserved
 * for crash scenario is mapped. memblock_add() forces the table to be mapped
 * in crashkernel case.
 *
 * Align the range to the nearest page borders. Ranges smaller than page size
 * are not going to be mapped.
 *
 * memblock_reserve() makes sure that future allocations will not touch the
 * table.
 */

static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
{
        phys_addr_t start, end;

        start = PAGE_ALIGN_DOWN(efi.unaccepted);
        end = PAGE_ALIGN(efi.unaccepted + sizeof(*unaccepted) + unaccepted->size);

        memblock_add(start, end - start);
        memblock_reserve(start, end - start);
}

int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
                                   int count,
                                   const efi_config_table_type_t *arch_tables)
{
        const efi_config_table_64_t *tbl64 = (void *)config_tables;
        const efi_config_table_32_t *tbl32 = (void *)config_tables;
        const efi_guid_t *guid;
        unsigned long table;
        int i;

        pr_info("");
        for (i = 0; i < count; i++) {
                if (!IS_ENABLED(CONFIG_X86)) {
                        guid = &config_tables[i].guid;
                        table = (unsigned long)config_tables[i].table;
                } else if (efi_enabled(EFI_64BIT)) {
                        guid = &tbl64[i].guid;
                        table = tbl64[i].table;

                        if (IS_ENABLED(CONFIG_X86_32) &&
                            tbl64[i].table > U32_MAX) {
                                pr_cont("\n");
                                pr_err("Table located above 4GB, disabling EFI.\n");
                                return -EINVAL;
                        }
                } else {
                        guid = &tbl32[i].guid;
                        table = tbl32[i].table;
                }

                if (!match_config_table(guid, table, common_tables) && arch_tables)
                        match_config_table(guid, table, arch_tables);
        }
        pr_cont("\n");
        set_bit(EFI_CONFIG_TABLES, &efi.flags);

        if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
                struct linux_efi_random_seed *seed;
                u32 size = 0;

                seed = early_memremap(efi_rng_seed, sizeof(*seed));
                if (seed != NULL) {
                        size = min_t(u32, seed->size, SZ_1K); // sanity check
                        early_memunmap(seed, sizeof(*seed));
                } else {
                        pr_err("Could not map UEFI random seed!\n");
                }
                if (size > 0) {
                        seed = early_memremap(efi_rng_seed,
                                              sizeof(*seed) + size);
                        if (seed != NULL) {
                                add_bootloader_randomness(seed->bits, size);
                                memzero_explicit(seed->bits, size);
                                early_memunmap(seed, sizeof(*seed) + size);
                        } else {
                                pr_err("Could not map UEFI random seed!\n");
                        }
                }
        }

        if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
                efi_memattr_init();

        efi_tpm_eventlog_init();

        if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
                unsigned long prsv = mem_reserve;

                while (prsv) {
                        struct linux_efi_memreserve *rsv;
                        u8 *p;

                        /*
                         * Just map a full page: that is what we will get
                         * anyway, and it permits us to map the entire entry
                         * before knowing its size.
                         */
                        p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
                                           PAGE_SIZE);
                        if (p == NULL) {
                                pr_err("Could not map UEFI memreserve entry!\n");
                                return -ENOMEM;
                        }

                        rsv = (void *)(p + prsv % PAGE_SIZE);

                        /* reserve the entry itself */
                        memblock_reserve(prsv,
                                         struct_size(rsv, entry, rsv->size));

                        for (i = 0; i < atomic_read(&rsv->count); i++) {
                                memblock_reserve(rsv->entry[i].base,
                                                 rsv->entry[i].size);
                        }

                        prsv = rsv->next;
                        early_memunmap(p, PAGE_SIZE);
                }
        }

        if (rt_prop != EFI_INVALID_TABLE_ADDR) {
                efi_rt_properties_table_t *tbl;

                tbl = early_memremap(rt_prop, sizeof(*tbl));
                if (tbl) {
                        efi.runtime_supported_mask &= tbl->runtime_services_supported;
                        early_memunmap(tbl, sizeof(*tbl));
                }
        }

        if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
            initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
                struct linux_efi_initrd *tbl;

                tbl = early_memremap(initrd, sizeof(*tbl));
                if (tbl) {
                        phys_initrd_start = tbl->base;
                        phys_initrd_size = tbl->size;
                        tbl->base = tbl->size = 0;
                        early_memunmap(tbl, sizeof(*tbl));
                }
        }

        if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) &&
            efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
                struct efi_unaccepted_memory *unaccepted;

                unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted));
                if (unaccepted) {

                        if (unaccepted->version == 1) {
                                reserve_unaccepted(unaccepted);
                        } else {
                                efi.unaccepted = EFI_INVALID_TABLE_ADDR;
                        }

                        early_memunmap(unaccepted, sizeof(*unaccepted));
                }
        }

        return 0;
}

int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
{
        if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
                pr_err("System table signature incorrect!\n");
                return -EINVAL;
        }

        return 0;
}

static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
                                                size_t size)
{
        const efi_char16_t *ret;

        ret = early_memremap_ro(fw_vendor, size);
        if (!ret)
                pr_err("Could not map the firmware vendor!\n");
        return ret;
}

static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
{
        early_memunmap((void *)fw_vendor, size);
}

void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
                                     unsigned long fw_vendor)
{
        char vendor[100] = "unknown";
        const efi_char16_t *c16;
        size_t i;
        u16 rev;

        c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
        if (c16) {
                for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
                        vendor[i] = c16[i];
                vendor[i] = '\0';

                unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
        }

        rev = (u16)systab_hdr->revision;
        pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);

        rev %= 10;
        if (rev)
                pr_cont(".%u", rev);

        pr_cont(" by %s\n", vendor);

        if (IS_ENABLED(CONFIG_X86_64) &&
            systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
            !strcmp(vendor, "Apple")) {
                pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
                efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
        }
}

static __initdata char memory_type_name[][13] = {
        "Reserved",
        "Loader Code",
        "Loader Data",
        "Boot Code",
        "Boot Data",
        "Runtime Code",
        "Runtime Data",
        "Conventional",
        "Unusable",
        "ACPI Reclaim",
        "ACPI Mem NVS",
        "MMIO",
        "MMIO Port",
        "PAL Code",
        "Persistent",
        "Unaccepted",
};

char * __init efi_md_typeattr_format(char *buf, size_t size,
                                     const efi_memory_desc_t *md)
{
        char *pos;
        int type_len;
        u64 attr;

        pos = buf;
        if (md->type >= ARRAY_SIZE(memory_type_name))
                type_len = snprintf(pos, size, "[type=%u", md->type);
        else
                type_len = snprintf(pos, size, "[%-*s",
                                    (int)(sizeof(memory_type_name[0]) - 1),
                                    memory_type_name[md->type]);
        if (type_len >= size)
                return buf;

        pos += type_len;
        size -= type_len;

        attr = md->attribute;
        if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
                     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
                     EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
                     EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
                     EFI_MEMORY_MORE_RELIABLE | EFI_MEMORY_HOT_PLUGGABLE |
                     EFI_MEMORY_RUNTIME))
                snprintf(pos, size, "|attr=0x%016llx]",
                         (unsigned long long)attr);
        else
                snprintf(pos, size,
                         "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
                         attr & EFI_MEMORY_RUNTIME              ? "RUN" : "",
                         attr & EFI_MEMORY_HOT_PLUGGABLE        ? "HP"  : "",
                         attr & EFI_MEMORY_MORE_RELIABLE        ? "MR"  : "",
                         attr & EFI_MEMORY_CPU_CRYPTO           ? "CC"  : "",
                         attr & EFI_MEMORY_SP                   ? "SP"  : "",
                         attr & EFI_MEMORY_NV                   ? "NV"  : "",
                         attr & EFI_MEMORY_XP                   ? "XP"  : "",
                         attr & EFI_MEMORY_RP                   ? "RP"  : "",
                         attr & EFI_MEMORY_WP                   ? "WP"  : "",
                         attr & EFI_MEMORY_RO                   ? "RO"  : "",
                         attr & EFI_MEMORY_UCE                  ? "UCE" : "",
                         attr & EFI_MEMORY_WB                   ? "WB"  : "",
                         attr & EFI_MEMORY_WT                   ? "WT"  : "",
                         attr & EFI_MEMORY_WC                   ? "WC"  : "",
                         attr & EFI_MEMORY_UC                   ? "UC"  : "");
        return buf;
}

/*
 * efi_mem_attributes - lookup memmap attributes for physical address
 * @phys_addr: the physical address to lookup
 *
 * Search in the EFI memory map for the region covering
 * @phys_addr. Returns the EFI memory attributes if the region
 * was found in the memory map, 0 otherwise.
 */
u64 efi_mem_attributes(unsigned long phys_addr)
{
        efi_memory_desc_t md;

        if (efi_mem_desc_lookup(phys_addr, &md))
                return 0;

        return md.attribute;
}

/*
 * efi_mem_type - lookup memmap type for physical address
 * @phys_addr: the physical address to lookup
 *
 * Search in the EFI memory map for the region covering @phys_addr.
 * Returns the EFI memory type if the region was found in the memory
 * map, -EINVAL otherwise.
 */
int efi_mem_type(unsigned long phys_addr)
{
        efi_memory_desc_t md;

        if (!efi_enabled(EFI_MEMMAP) && !efi_enabled(EFI_PARAVIRT))
                return -ENOTSUPP;

        if (efi_mem_desc_lookup(phys_addr, &md))
                return -EINVAL;

        return md.type;
}

int efi_status_to_err(efi_status_t status)
{
        int err;

        switch (status) {
        case EFI_SUCCESS:
                err = 0;
                break;
        case EFI_INVALID_PARAMETER:
                err = -EINVAL;
                break;
        case EFI_OUT_OF_RESOURCES:
                err = -ENOSPC;
                break;
        case EFI_DEVICE_ERROR:
                err = -EIO;
                break;
        case EFI_WRITE_PROTECTED:
                err = -EROFS;
                break;
        case EFI_SECURITY_VIOLATION:
                err = -EACCES;
                break;
        case EFI_NOT_FOUND:
                err = -ENOENT;
                break;
        case EFI_ABORTED:
                err = -EINTR;
                break;
        default:
                err = -EINVAL;
        }

        return err;
}
EXPORT_SYMBOL_GPL(efi_status_to_err);

static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;

static int __init efi_memreserve_map_root(void)
{
        if (mem_reserve == EFI_INVALID_TABLE_ADDR)
                return -ENODEV;

        efi_memreserve_root = memremap(mem_reserve,
                                       sizeof(*efi_memreserve_root),
                                       MEMREMAP_WB);
        if (WARN_ON_ONCE(!efi_memreserve_root))
                return -ENOMEM;
        return 0;
}

static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
{
        struct resource *res, *parent;
        int ret;

        res = kzalloc_obj(struct resource, GFP_ATOMIC);
        if (!res)
                return -ENOMEM;

        res->name       = "reserved";
        res->flags      = IORESOURCE_MEM;
        res->start      = addr;
        res->end        = addr + size - 1;

        /* we expect a conflict with a 'System RAM' region */
        parent = request_resource_conflict(&iomem_resource, res);
        ret = parent ? request_resource(parent, res) : 0;

        /*
         * Given that efi_mem_reserve_iomem() can be called at any
         * time, only call memblock_reserve() if the architecture
         * keeps the infrastructure around.
         */
        if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
                memblock_reserve(addr, size);

        return ret;
}

int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
{
        struct linux_efi_memreserve *rsv;
        unsigned long prsv;
        int rc, index;

        if (efi_memreserve_root == (void *)ULONG_MAX)
                return -ENODEV;

        if (!efi_memreserve_root) {
                rc = efi_memreserve_map_root();
                if (rc)
                        return rc;
        }

        /* first try to find a slot in an existing linked list entry */
        for (prsv = efi_memreserve_root->next; prsv; ) {
                rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
                if (!rsv)
                        return -ENOMEM;
                index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
                if (index < rsv->size) {
                        rsv->entry[index].base = addr;
                        rsv->entry[index].size = size;

                        memunmap(rsv);
                        return efi_mem_reserve_iomem(addr, size);
                }
                prsv = rsv->next;
                memunmap(rsv);
        }

        /* no slot found - allocate a new linked list entry */
        rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
        if (!rsv)
                return -ENOMEM;

        rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
        if (rc) {
                free_page((unsigned long)rsv);
                return rc;
        }

        /*
         * The memremap() call above assumes that a linux_efi_memreserve entry
         * never crosses a page boundary, so let's ensure that this remains true
         * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
         * using SZ_4K explicitly in the size calculation below.
         */
        rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
        atomic_set(&rsv->count, 1);
        rsv->entry[0].base = addr;
        rsv->entry[0].size = size;

        spin_lock(&efi_mem_reserve_persistent_lock);
        rsv->next = efi_memreserve_root->next;
        efi_memreserve_root->next = __pa(rsv);
        spin_unlock(&efi_mem_reserve_persistent_lock);

        return efi_mem_reserve_iomem(addr, size);
}

static int __init efi_memreserve_root_init(void)
{
        if (efi_memreserve_root)
                return 0;
        if (efi_memreserve_map_root())
                efi_memreserve_root = (void *)ULONG_MAX;
        return 0;
}
early_initcall(efi_memreserve_root_init);

#ifdef CONFIG_KEXEC
static int update_efi_random_seed(struct notifier_block *nb,
                                  unsigned long code, void *unused)
{
        struct linux_efi_random_seed *seed;
        u32 size = 0;

        if (!kexec_in_progress)
                return NOTIFY_DONE;

        seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
        if (seed != NULL) {
                size = min(seed->size, EFI_RANDOM_SEED_SIZE);
                memunmap(seed);
        } else {
                pr_err("Could not map UEFI random seed!\n");
        }
        if (size > 0) {
                seed = memremap(efi_rng_seed, sizeof(*seed) + size,
                                MEMREMAP_WB);
                if (seed != NULL) {
                        seed->size = size;
                        get_random_bytes(seed->bits, seed->size);
                        memunmap(seed);
                } else {
                        pr_err("Could not map UEFI random seed!\n");
                }
        }
        return NOTIFY_DONE;
}

static struct notifier_block efi_random_seed_nb = {
        .notifier_call = update_efi_random_seed,
};

static int __init register_update_efi_random_seed(void)
{
        if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
                return 0;
        return register_reboot_notifier(&efi_random_seed_nb);
}
late_initcall(register_update_efi_random_seed);
#endif