diff options
Diffstat (limited to 'drivers/acpi/apei/erst.c')
| -rw-r--r-- | drivers/acpi/apei/erst.c | 1206 |
1 files changed, 1206 insertions, 0 deletions
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c new file mode 100644 index 000000000..83efb52a3 --- /dev/null +++ b/drivers/acpi/apei/erst.c @@ -0,0 +1,1206 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * APEI Error Record Serialization Table support + * + * ERST is a way provided by APEI to save and retrieve hardware error + * information to and from a persistent store. + * + * For more information about ERST, please refer to ACPI Specification + * version 4.0, section 17.4. + * + * Copyright 2010 Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/acpi.h> +#include <linux/uaccess.h> +#include <linux/cper.h> +#include <linux/nmi.h> +#include <linux/hardirq.h> +#include <linux/pstore.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> /* kvfree() */ +#include <acpi/apei.h> + +#include "apei-internal.h" + +#undef pr_fmt +#define pr_fmt(fmt) "ERST: " fmt + +/* ERST command status */ +#define ERST_STATUS_SUCCESS 0x0 +#define ERST_STATUS_NOT_ENOUGH_SPACE 0x1 +#define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x2 +#define ERST_STATUS_FAILED 0x3 +#define ERST_STATUS_RECORD_STORE_EMPTY 0x4 +#define ERST_STATUS_RECORD_NOT_FOUND 0x5 + +#define ERST_TAB_ENTRY(tab) \ + ((struct acpi_whea_header *)((char *)(tab) + \ + sizeof(struct acpi_table_erst))) + +#define SPIN_UNIT 100 /* 100ns */ +/* Firmware should respond within 1 milliseconds */ +#define FIRMWARE_TIMEOUT (1 * NSEC_PER_MSEC) +#define FIRMWARE_MAX_STALL 50 /* 50us */ + +int erst_disable; +EXPORT_SYMBOL_GPL(erst_disable); + +static struct acpi_table_erst *erst_tab; + +/* ERST Error Log Address Range atrributes */ +#define ERST_RANGE_RESERVED 0x0001 +#define ERST_RANGE_NVRAM 0x0002 +#define ERST_RANGE_SLOW 0x0004 + +/* + * ERST Error Log Address Range, used as buffer for reading/writing + * error records. + */ +static struct erst_erange { + u64 base; + u64 size; + void __iomem *vaddr; + u32 attr; +} erst_erange; + +/* + * Prevent ERST interpreter to run simultaneously, because the + * corresponding firmware implementation may not work properly when + * invoked simultaneously. + * + * It is used to provide exclusive accessing for ERST Error Log + * Address Range too. + */ +static DEFINE_RAW_SPINLOCK(erst_lock); + +static inline int erst_errno(int command_status) +{ + switch (command_status) { + case ERST_STATUS_SUCCESS: + return 0; + case ERST_STATUS_HARDWARE_NOT_AVAILABLE: + return -ENODEV; + case ERST_STATUS_NOT_ENOUGH_SPACE: + return -ENOSPC; + case ERST_STATUS_RECORD_STORE_EMPTY: + case ERST_STATUS_RECORD_NOT_FOUND: + return -ENOENT; + default: + return -EINVAL; + } +} + +static int erst_timedout(u64 *t, u64 spin_unit) +{ + if ((s64)*t < spin_unit) { + pr_warn(FW_WARN "Firmware does not respond in time.\n"); + return 1; + } + *t -= spin_unit; + ndelay(spin_unit); + touch_nmi_watchdog(); + return 0; +} + +static int erst_exec_load_var1(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + return __apei_exec_read_register(entry, &ctx->var1); +} + +static int erst_exec_load_var2(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + return __apei_exec_read_register(entry, &ctx->var2); +} + +static int erst_exec_store_var1(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + return __apei_exec_write_register(entry, ctx->var1); +} + +static int erst_exec_add(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + ctx->var1 += ctx->var2; + return 0; +} + +static int erst_exec_subtract(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + ctx->var1 -= ctx->var2; + return 0; +} + +static int erst_exec_add_value(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + int rc; + u64 val; + + rc = __apei_exec_read_register(entry, &val); + if (rc) + return rc; + val += ctx->value; + rc = __apei_exec_write_register(entry, val); + return rc; +} + +static int erst_exec_subtract_value(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + int rc; + u64 val; + + rc = __apei_exec_read_register(entry, &val); + if (rc) + return rc; + val -= ctx->value; + rc = __apei_exec_write_register(entry, val); + return rc; +} + +static int erst_exec_stall(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + u64 stall_time; + + if (ctx->value > FIRMWARE_MAX_STALL) { + if (!in_nmi()) + pr_warn(FW_WARN + "Too long stall time for stall instruction: 0x%llx.\n", + ctx->value); + stall_time = FIRMWARE_MAX_STALL; + } else + stall_time = ctx->value; + udelay(stall_time); + return 0; +} + +static int erst_exec_stall_while_true(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + int rc; + u64 val; + u64 timeout = FIRMWARE_TIMEOUT; + u64 stall_time; + + if (ctx->var1 > FIRMWARE_MAX_STALL) { + if (!in_nmi()) + pr_warn(FW_WARN + "Too long stall time for stall while true instruction: 0x%llx.\n", + ctx->var1); + stall_time = FIRMWARE_MAX_STALL; + } else + stall_time = ctx->var1; + + for (;;) { + rc = __apei_exec_read_register(entry, &val); + if (rc) + return rc; + if (val != ctx->value) + break; + if (erst_timedout(&timeout, stall_time * NSEC_PER_USEC)) + return -EIO; + } + return 0; +} + +static int erst_exec_skip_next_instruction_if_true( + struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + int rc; + u64 val; + + rc = __apei_exec_read_register(entry, &val); + if (rc) + return rc; + if (val == ctx->value) { + ctx->ip += 2; + return APEI_EXEC_SET_IP; + } + + return 0; +} + +static int erst_exec_goto(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + ctx->ip = ctx->value; + return APEI_EXEC_SET_IP; +} + +static int erst_exec_set_src_address_base(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + return __apei_exec_read_register(entry, &ctx->src_base); +} + +static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + return __apei_exec_read_register(entry, &ctx->dst_base); +} + +static int erst_exec_move_data(struct apei_exec_context *ctx, + struct acpi_whea_header *entry) +{ + int rc; + u64 offset; + void *src, *dst; + + /* ioremap does not work in interrupt context */ + if (in_interrupt()) { + pr_warn("MOVE_DATA can not be used in interrupt context.\n"); + return -EBUSY; + } + + rc = __apei_exec_read_register(entry, &offset); + if (rc) + return rc; + + src = ioremap(ctx->src_base + offset, ctx->var2); + if (!src) + return -ENOMEM; + dst = ioremap(ctx->dst_base + offset, ctx->var2); + if (!dst) { + iounmap(src); + return -ENOMEM; + } + + memmove(dst, src, ctx->var2); + + iounmap(src); + iounmap(dst); + + return 0; +} + +static struct apei_exec_ins_type erst_ins_type[] = { + [ACPI_ERST_READ_REGISTER] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = apei_exec_read_register, + }, + [ACPI_ERST_READ_REGISTER_VALUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = apei_exec_read_register_value, + }, + [ACPI_ERST_WRITE_REGISTER] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = apei_exec_write_register, + }, + [ACPI_ERST_WRITE_REGISTER_VALUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = apei_exec_write_register_value, + }, + [ACPI_ERST_NOOP] = { + .flags = 0, + .run = apei_exec_noop, + }, + [ACPI_ERST_LOAD_VAR1] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_load_var1, + }, + [ACPI_ERST_LOAD_VAR2] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_load_var2, + }, + [ACPI_ERST_STORE_VAR1] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_store_var1, + }, + [ACPI_ERST_ADD] = { + .flags = 0, + .run = erst_exec_add, + }, + [ACPI_ERST_SUBTRACT] = { + .flags = 0, + .run = erst_exec_subtract, + }, + [ACPI_ERST_ADD_VALUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_add_value, + }, + [ACPI_ERST_SUBTRACT_VALUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_subtract_value, + }, + [ACPI_ERST_STALL] = { + .flags = 0, + .run = erst_exec_stall, + }, + [ACPI_ERST_STALL_WHILE_TRUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_stall_while_true, + }, + [ACPI_ERST_SKIP_NEXT_IF_TRUE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_skip_next_instruction_if_true, + }, + [ACPI_ERST_GOTO] = { + .flags = 0, + .run = erst_exec_goto, + }, + [ACPI_ERST_SET_SRC_ADDRESS_BASE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_set_src_address_base, + }, + [ACPI_ERST_SET_DST_ADDRESS_BASE] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_set_dst_address_base, + }, + [ACPI_ERST_MOVE_DATA] = { + .flags = APEI_EXEC_INS_ACCESS_REGISTER, + .run = erst_exec_move_data, + }, +}; + +static inline void erst_exec_ctx_init(struct apei_exec_context *ctx) +{ + apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type), + ERST_TAB_ENTRY(erst_tab), erst_tab->entries); +} + +static int erst_get_erange(struct erst_erange *range) +{ + struct apei_exec_context ctx; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE); + if (rc) + return rc; + range->base = apei_exec_ctx_get_output(&ctx); + rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH); + if (rc) + return rc; + range->size = apei_exec_ctx_get_output(&ctx); + rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES); + if (rc) + return rc; + range->attr = apei_exec_ctx_get_output(&ctx); + + return 0; +} + +static ssize_t __erst_get_record_count(void) +{ + struct apei_exec_context ctx; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT); + if (rc) + return rc; + return apei_exec_ctx_get_output(&ctx); +} + +ssize_t erst_get_record_count(void) +{ + ssize_t count; + unsigned long flags; + + if (erst_disable) + return -ENODEV; + + raw_spin_lock_irqsave(&erst_lock, flags); + count = __erst_get_record_count(); + raw_spin_unlock_irqrestore(&erst_lock, flags); + + return count; +} +EXPORT_SYMBOL_GPL(erst_get_record_count); + +#define ERST_RECORD_ID_CACHE_SIZE_MIN 16 +#define ERST_RECORD_ID_CACHE_SIZE_MAX 1024 + +struct erst_record_id_cache { + struct mutex lock; + u64 *entries; + int len; + int size; + int refcount; +}; + +static struct erst_record_id_cache erst_record_id_cache = { + .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock), + .refcount = 0, +}; + +static int __erst_get_next_record_id(u64 *record_id) +{ + struct apei_exec_context ctx; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID); + if (rc) + return rc; + *record_id = apei_exec_ctx_get_output(&ctx); + + return 0; +} + +int erst_get_record_id_begin(int *pos) +{ + int rc; + + if (erst_disable) + return -ENODEV; + + rc = mutex_lock_interruptible(&erst_record_id_cache.lock); + if (rc) + return rc; + erst_record_id_cache.refcount++; + mutex_unlock(&erst_record_id_cache.lock); + + *pos = 0; + + return 0; +} +EXPORT_SYMBOL_GPL(erst_get_record_id_begin); + +/* erst_record_id_cache.lock must be held by caller */ +static int __erst_record_id_cache_add_one(void) +{ + u64 id, prev_id, first_id; + int i, rc; + u64 *entries; + unsigned long flags; + + id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID; +retry: + raw_spin_lock_irqsave(&erst_lock, flags); + rc = __erst_get_next_record_id(&id); + raw_spin_unlock_irqrestore(&erst_lock, flags); + if (rc == -ENOENT) + return 0; + if (rc) + return rc; + if (id == APEI_ERST_INVALID_RECORD_ID) + return 0; + /* can not skip current ID, or loop back to first ID */ + if (id == prev_id || id == first_id) + return 0; + if (first_id == APEI_ERST_INVALID_RECORD_ID) + first_id = id; + prev_id = id; + + entries = erst_record_id_cache.entries; + for (i = 0; i < erst_record_id_cache.len; i++) { + if (entries[i] == id) + break; + } + /* record id already in cache, try next */ + if (i < erst_record_id_cache.len) + goto retry; + if (erst_record_id_cache.len >= erst_record_id_cache.size) { + int new_size; + u64 *new_entries; + + new_size = erst_record_id_cache.size * 2; + new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN, + ERST_RECORD_ID_CACHE_SIZE_MAX); + if (new_size <= erst_record_id_cache.size) { + if (printk_ratelimit()) + pr_warn(FW_WARN "too many record IDs!\n"); + return 0; + } + new_entries = kvmalloc_array(new_size, sizeof(entries[0]), + GFP_KERNEL); + if (!new_entries) + return -ENOMEM; + memcpy(new_entries, entries, + erst_record_id_cache.len * sizeof(entries[0])); + kvfree(entries); + erst_record_id_cache.entries = entries = new_entries; + erst_record_id_cache.size = new_size; + } + entries[i] = id; + erst_record_id_cache.len++; + + return 1; +} + +/* + * Get the record ID of an existing error record on the persistent + * storage. If there is no error record on the persistent storage, the + * returned record_id is APEI_ERST_INVALID_RECORD_ID. + */ +int erst_get_record_id_next(int *pos, u64 *record_id) +{ + int rc = 0; + u64 *entries; + + if (erst_disable) + return -ENODEV; + + /* must be enclosed by erst_get_record_id_begin/end */ + BUG_ON(!erst_record_id_cache.refcount); + BUG_ON(*pos < 0 || *pos > erst_record_id_cache.len); + + mutex_lock(&erst_record_id_cache.lock); + entries = erst_record_id_cache.entries; + for (; *pos < erst_record_id_cache.len; (*pos)++) + if (entries[*pos] != APEI_ERST_INVALID_RECORD_ID) + break; + /* found next record id in cache */ + if (*pos < erst_record_id_cache.len) { + *record_id = entries[*pos]; + (*pos)++; + goto out_unlock; + } + + /* Try to add one more record ID to cache */ + rc = __erst_record_id_cache_add_one(); + if (rc < 0) + goto out_unlock; + /* successfully add one new ID */ + if (rc == 1) { + *record_id = erst_record_id_cache.entries[*pos]; + (*pos)++; + rc = 0; + } else { + *pos = -1; + *record_id = APEI_ERST_INVALID_RECORD_ID; + } +out_unlock: + mutex_unlock(&erst_record_id_cache.lock); + + return rc; +} +EXPORT_SYMBOL_GPL(erst_get_record_id_next); + +/* erst_record_id_cache.lock must be held by caller */ +static void __erst_record_id_cache_compact(void) +{ + int i, wpos = 0; + u64 *entries; + + if (erst_record_id_cache.refcount) + return; + + entries = erst_record_id_cache.entries; + for (i = 0; i < erst_record_id_cache.len; i++) { + if (entries[i] == APEI_ERST_INVALID_RECORD_ID) + continue; + if (wpos != i) + entries[wpos] = entries[i]; + wpos++; + } + erst_record_id_cache.len = wpos; +} + +void erst_get_record_id_end(void) +{ + /* + * erst_disable != 0 should be detected by invoker via the + * return value of erst_get_record_id_begin/next, so this + * function should not be called for erst_disable != 0. + */ + BUG_ON(erst_disable); + + mutex_lock(&erst_record_id_cache.lock); + erst_record_id_cache.refcount--; + BUG_ON(erst_record_id_cache.refcount < 0); + __erst_record_id_cache_compact(); + mutex_unlock(&erst_record_id_cache.lock); +} +EXPORT_SYMBOL_GPL(erst_get_record_id_end); + +static int __erst_write_to_storage(u64 offset) +{ + struct apei_exec_context ctx; + u64 timeout = FIRMWARE_TIMEOUT; + u64 val; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE); + if (rc) + return rc; + apei_exec_ctx_set_input(&ctx, offset); + rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET); + if (rc) + return rc; + rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION); + if (rc) + return rc; + for (;;) { + rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + if (!val) + break; + if (erst_timedout(&timeout, SPIN_UNIT)) + return -EIO; + } + rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); + if (rc) + return rc; + + return erst_errno(val); +} + +static int __erst_read_from_storage(u64 record_id, u64 offset) +{ + struct apei_exec_context ctx; + u64 timeout = FIRMWARE_TIMEOUT; + u64 val; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ); + if (rc) + return rc; + apei_exec_ctx_set_input(&ctx, offset); + rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET); + if (rc) + return rc; + apei_exec_ctx_set_input(&ctx, record_id); + rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID); + if (rc) + return rc; + rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION); + if (rc) + return rc; + for (;;) { + rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + if (!val) + break; + if (erst_timedout(&timeout, SPIN_UNIT)) + return -EIO; + }; + rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); + if (rc) + return rc; + + return erst_errno(val); +} + +static int __erst_clear_from_storage(u64 record_id) +{ + struct apei_exec_context ctx; + u64 timeout = FIRMWARE_TIMEOUT; + u64 val; + int rc; + + erst_exec_ctx_init(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR); + if (rc) + return rc; + apei_exec_ctx_set_input(&ctx, record_id); + rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID); + if (rc) + return rc; + rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION); + if (rc) + return rc; + for (;;) { + rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + if (!val) + break; + if (erst_timedout(&timeout, SPIN_UNIT)) + return -EIO; + } + rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS); + if (rc) + return rc; + val = apei_exec_ctx_get_output(&ctx); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); + if (rc) + return rc; + + return erst_errno(val); +} + +/* NVRAM ERST Error Log Address Range is not supported yet */ +static void pr_unimpl_nvram(void) +{ + if (printk_ratelimit()) + pr_warn("NVRAM ERST Log Address Range not implemented yet.\n"); +} + +static int __erst_write_to_nvram(const struct cper_record_header *record) +{ + /* do not print message, because printk is not safe for NMI */ + return -ENOSYS; +} + +static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset) +{ + pr_unimpl_nvram(); + return -ENOSYS; +} + +static int __erst_clear_from_nvram(u64 record_id) +{ + pr_unimpl_nvram(); + return -ENOSYS; +} + +int erst_write(const struct cper_record_header *record) +{ + int rc; + unsigned long flags; + struct cper_record_header *rcd_erange; + + if (erst_disable) + return -ENODEV; + + if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE)) + return -EINVAL; + + if (erst_erange.attr & ERST_RANGE_NVRAM) { + if (!raw_spin_trylock_irqsave(&erst_lock, flags)) + return -EBUSY; + rc = __erst_write_to_nvram(record); + raw_spin_unlock_irqrestore(&erst_lock, flags); + return rc; + } + + if (record->record_length > erst_erange.size) + return -EINVAL; + + if (!raw_spin_trylock_irqsave(&erst_lock, flags)) + return -EBUSY; + memcpy(erst_erange.vaddr, record, record->record_length); + rcd_erange = erst_erange.vaddr; + /* signature for serialization system */ + memcpy(&rcd_erange->persistence_information, "ER", 2); + + rc = __erst_write_to_storage(0); + raw_spin_unlock_irqrestore(&erst_lock, flags); + + return rc; +} +EXPORT_SYMBOL_GPL(erst_write); + +static int __erst_read_to_erange(u64 record_id, u64 *offset) +{ + int rc; + + if (erst_erange.attr & ERST_RANGE_NVRAM) + return __erst_read_to_erange_from_nvram( + record_id, offset); + + rc = __erst_read_from_storage(record_id, 0); + if (rc) + return rc; + *offset = 0; + + return 0; +} + +static ssize_t __erst_read(u64 record_id, struct cper_record_header *record, + size_t buflen) +{ + int rc; + u64 offset, len = 0; + struct cper_record_header *rcd_tmp; + + rc = __erst_read_to_erange(record_id, &offset); + if (rc) + return rc; + rcd_tmp = erst_erange.vaddr + offset; + len = rcd_tmp->record_length; + if (len <= buflen) + memcpy(record, rcd_tmp, len); + + return len; +} + +/* + * If return value > buflen, the buffer size is not big enough, + * else if return value < 0, something goes wrong, + * else everything is OK, and return value is record length + */ +ssize_t erst_read(u64 record_id, struct cper_record_header *record, + size_t buflen) +{ + ssize_t len; + unsigned long flags; + + if (erst_disable) + return -ENODEV; + + raw_spin_lock_irqsave(&erst_lock, flags); + len = __erst_read(record_id, record, buflen); + raw_spin_unlock_irqrestore(&erst_lock, flags); + return len; +} +EXPORT_SYMBOL_GPL(erst_read); + +int erst_clear(u64 record_id) +{ + int rc, i; + unsigned long flags; + u64 *entries; + + if (erst_disable) + return -ENODEV; + + rc = mutex_lock_interruptible(&erst_record_id_cache.lock); + if (rc) + return rc; + raw_spin_lock_irqsave(&erst_lock, flags); + if (erst_erange.attr & ERST_RANGE_NVRAM) + rc = __erst_clear_from_nvram(record_id); + else + rc = __erst_clear_from_storage(record_id); + raw_spin_unlock_irqrestore(&erst_lock, flags); + if (rc) + goto out; + entries = erst_record_id_cache.entries; + for (i = 0; i < erst_record_id_cache.len; i++) { + if (entries[i] == record_id) + entries[i] = APEI_ERST_INVALID_RECORD_ID; + } + __erst_record_id_cache_compact(); +out: + mutex_unlock(&erst_record_id_cache.lock); + return rc; +} +EXPORT_SYMBOL_GPL(erst_clear); + +static int __init setup_erst_disable(char *str) +{ + erst_disable = 1; + return 1; +} + +__setup("erst_disable", setup_erst_disable); + +static int erst_check_table(struct acpi_table_erst *erst_tab) +{ + if ((erst_tab->header_length != + (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header))) + && (erst_tab->header_length != sizeof(struct acpi_table_erst))) + return -EINVAL; + if (erst_tab->header.length < sizeof(struct acpi_table_erst)) + return -EINVAL; + if (erst_tab->entries != + (erst_tab->header.length - sizeof(struct acpi_table_erst)) / + sizeof(struct acpi_erst_entry)) + return -EINVAL; + + return 0; +} + +static int erst_open_pstore(struct pstore_info *psi); +static int erst_close_pstore(struct pstore_info *psi); +static ssize_t erst_reader(struct pstore_record *record); +static int erst_writer(struct pstore_record *record); +static int erst_clearer(struct pstore_record *record); + +static struct pstore_info erst_info = { + .owner = THIS_MODULE, + .name = "erst", + .flags = PSTORE_FLAGS_DMESG, + .open = erst_open_pstore, + .close = erst_close_pstore, + .read = erst_reader, + .write = erst_writer, + .erase = erst_clearer +}; + +#define CPER_CREATOR_PSTORE \ + GUID_INIT(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \ + 0x64, 0x90, 0xb8, 0x9d) +#define CPER_SECTION_TYPE_DMESG \ + GUID_INIT(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \ + 0x94, 0x19, 0xeb, 0x12) +#define CPER_SECTION_TYPE_DMESG_Z \ + GUID_INIT(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d, \ + 0x34, 0xdd, 0xfa, 0xc6) +#define CPER_SECTION_TYPE_MCE \ + GUID_INIT(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \ + 0x04, 0x4a, 0x38, 0xfc) + +struct cper_pstore_record { + struct cper_record_header hdr; + struct cper_section_descriptor sec_hdr; + char data[]; +} __packed; + +static int reader_pos; + +static int erst_open_pstore(struct pstore_info *psi) +{ + int rc; + + if (erst_disable) + return -ENODEV; + + rc = erst_get_record_id_begin(&reader_pos); + + return rc; +} + +static int erst_close_pstore(struct pstore_info *psi) +{ + erst_get_record_id_end(); + + return 0; +} + +static ssize_t erst_reader(struct pstore_record *record) +{ + int rc; + ssize_t len = 0; + u64 record_id; + struct cper_pstore_record *rcd; + size_t rcd_len = sizeof(*rcd) + erst_info.bufsize; + + if (erst_disable) + return -ENODEV; + + rcd = kmalloc(rcd_len, GFP_KERNEL); + if (!rcd) { + rc = -ENOMEM; + goto out; + } +skip: + rc = erst_get_record_id_next(&reader_pos, &record_id); + if (rc) + goto out; + + /* no more record */ + if (record_id == APEI_ERST_INVALID_RECORD_ID) { + rc = -EINVAL; + goto out; + } + + len = erst_read(record_id, &rcd->hdr, rcd_len); + /* The record may be cleared by others, try read next record */ + if (len == -ENOENT) + goto skip; + else if (len < 0 || len < sizeof(*rcd)) { + rc = -EIO; + goto out; + } + if (!guid_equal(&rcd->hdr.creator_id, &CPER_CREATOR_PSTORE)) + goto skip; + + record->buf = kmalloc(len, GFP_KERNEL); + if (record->buf == NULL) { + rc = -ENOMEM; + goto out; + } + memcpy(record->buf, rcd->data, len - sizeof(*rcd)); + record->id = record_id; + record->compressed = false; + record->ecc_notice_size = 0; + if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG_Z)) { + record->type = PSTORE_TYPE_DMESG; + record->compressed = true; + } else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG)) + record->type = PSTORE_TYPE_DMESG; + else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_MCE)) + record->type = PSTORE_TYPE_MCE; + else + record->type = PSTORE_TYPE_MAX; + + if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP) + record->time.tv_sec = rcd->hdr.timestamp; + else + record->time.tv_sec = 0; + record->time.tv_nsec = 0; + +out: + kfree(rcd); + return (rc < 0) ? rc : (len - sizeof(*rcd)); +} + +static int erst_writer(struct pstore_record *record) +{ + struct cper_pstore_record *rcd = (struct cper_pstore_record *) + (erst_info.buf - sizeof(*rcd)); + int ret; + + memset(rcd, 0, sizeof(*rcd)); + memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE); + rcd->hdr.revision = CPER_RECORD_REV; + rcd->hdr.signature_end = CPER_SIG_END; + rcd->hdr.section_count = 1; + rcd->hdr.error_severity = CPER_SEV_FATAL; + /* timestamp valid. platform_id, partition_id are invalid */ + rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP; + rcd->hdr.timestamp = ktime_get_real_seconds(); + rcd->hdr.record_length = sizeof(*rcd) + record->size; + rcd->hdr.creator_id = CPER_CREATOR_PSTORE; + rcd->hdr.notification_type = CPER_NOTIFY_MCE; + rcd->hdr.record_id = cper_next_record_id(); + rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR; + + rcd->sec_hdr.section_offset = sizeof(*rcd); + rcd->sec_hdr.section_length = record->size; + rcd->sec_hdr.revision = CPER_SEC_REV; + /* fru_id and fru_text is invalid */ + rcd->sec_hdr.validation_bits = 0; + rcd->sec_hdr.flags = CPER_SEC_PRIMARY; + switch (record->type) { + case PSTORE_TYPE_DMESG: + if (record->compressed) + rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z; + else + rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG; + break; + case PSTORE_TYPE_MCE: + rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE; + break; + default: + return -EINVAL; + } + rcd->sec_hdr.section_severity = CPER_SEV_FATAL; + + ret = erst_write(&rcd->hdr); + record->id = rcd->hdr.record_id; + + return ret; +} + +static int erst_clearer(struct pstore_record *record) +{ + return erst_clear(record->id); +} + +static int __init erst_init(void) +{ + int rc = 0; + acpi_status status; + struct apei_exec_context ctx; + struct apei_resources erst_resources; + struct resource *r; + char *buf; + + if (acpi_disabled) + goto err; + + if (erst_disable) { + pr_info( + "Error Record Serialization Table (ERST) support is disabled.\n"); + goto err; + } + + status = acpi_get_table(ACPI_SIG_ERST, 0, + (struct acpi_table_header **)&erst_tab); + if (status == AE_NOT_FOUND) + goto err; + else if (ACPI_FAILURE(status)) { + const char *msg = acpi_format_exception(status); + pr_err("Failed to get table, %s\n", msg); + rc = -EINVAL; + goto err; + } + + rc = erst_check_table(erst_tab); + if (rc) { + pr_err(FW_BUG "ERST table is invalid.\n"); + goto err_put_erst_tab; + } + + apei_resources_init(&erst_resources); + erst_exec_ctx_init(&ctx); + rc = apei_exec_collect_resources(&ctx, &erst_resources); + if (rc) + goto err_fini; + rc = apei_resources_request(&erst_resources, "APEI ERST"); + if (rc) + goto err_fini; + rc = apei_exec_pre_map_gars(&ctx); + if (rc) + goto err_release; + rc = erst_get_erange(&erst_erange); + if (rc) { + if (rc == -ENODEV) + pr_info( + "The corresponding hardware device or firmware implementation " + "is not available.\n"); + else + pr_err("Failed to get Error Log Address Range.\n"); + goto err_unmap_reg; + } + + r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST"); + if (!r) { + pr_err("Can not request [mem %#010llx-%#010llx] for ERST.\n", + (unsigned long long)erst_erange.base, + (unsigned long long)erst_erange.base + erst_erange.size - 1); + rc = -EIO; + goto err_unmap_reg; + } + rc = -ENOMEM; + erst_erange.vaddr = ioremap_cache(erst_erange.base, + erst_erange.size); + if (!erst_erange.vaddr) + goto err_release_erange; + + pr_info( + "Error Record Serialization Table (ERST) support is initialized.\n"); + + buf = kmalloc(erst_erange.size, GFP_KERNEL); + if (buf) { + erst_info.buf = buf + sizeof(struct cper_pstore_record); + erst_info.bufsize = erst_erange.size - + sizeof(struct cper_pstore_record); + rc = pstore_register(&erst_info); + if (rc) { + if (rc != -EPERM) + pr_info( + "Could not register with persistent store.\n"); + erst_info.buf = NULL; + erst_info.bufsize = 0; + kfree(buf); + } + } else + pr_err( + "Failed to allocate %lld bytes for persistent store error log.\n", + erst_erange.size); + + /* Cleanup ERST Resources */ + apei_resources_fini(&erst_resources); + + return 0; + +err_release_erange: + release_mem_region(erst_erange.base, erst_erange.size); +err_unmap_reg: + apei_exec_post_unmap_gars(&ctx); +err_release: + apei_resources_release(&erst_resources); +err_fini: + apei_resources_fini(&erst_resources); +err_put_erst_tab: + acpi_put_table((struct acpi_table_header *)erst_tab); +err: + erst_disable = 1; + return rc; +} + +device_initcall(erst_init); |