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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/acpi/apei/erst.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/acpi/apei/erst.c')
-rw-r--r--drivers/acpi/apei/erst.c1267
1 files changed, 1267 insertions, 0 deletions
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
new file mode 100644
index 0000000000..247989060e
--- /dev/null
+++ b/drivers/acpi/apei/erst.c
@@ -0,0 +1,1267 @@
+// 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 attributes */
+#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);
+
+static void erst_clear_cache(u64 record_id)
+{
+ int i;
+ u64 *entries;
+
+ mutex_lock(&erst_record_id_cache.lock);
+
+ 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();
+
+ mutex_unlock(&erst_record_id_cache.lock);
+}
+
+ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,
+ size_t buflen, size_t recordlen, const guid_t *creatorid)
+{
+ ssize_t len;
+
+ /*
+ * if creatorid is NULL, read any record for erst-dbg module
+ */
+ if (creatorid == NULL) {
+ len = erst_read(record_id, record, buflen);
+ if (len == -ENOENT)
+ erst_clear_cache(record_id);
+
+ return len;
+ }
+
+ len = erst_read(record_id, record, buflen);
+ /*
+ * if erst_read return value is -ENOENT skip to next record_id,
+ * and clear the record_id cache.
+ */
+ if (len == -ENOENT) {
+ erst_clear_cache(record_id);
+ goto out;
+ }
+
+ if (len < 0)
+ goto out;
+
+ /*
+ * if erst_read return value is less than record head length,
+ * consider it as -EIO, and clear the record_id cache.
+ */
+ if (len < recordlen) {
+ len = -EIO;
+ erst_clear_cache(record_id);
+ goto out;
+ }
+
+ /*
+ * if creatorid is not wanted, consider it as not found,
+ * for skipping to next record_id.
+ */
+ if (!guid_equal(&record->creator_id, creatorid))
+ len = -ENOENT;
+
+out:
+ return len;
+}
+EXPORT_SYMBOL_GPL(erst_read_record);
+
+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)
+{
+ if (erst_disable)
+ return -ENODEV;
+
+ return erst_get_record_id_begin(&reader_pos);
+}
+
+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(record_id, &rcd->hdr, rcd_len, sizeof(*rcd),
+ &CPER_CREATOR_PSTORE);
+ /* The record may be cleared by others, try read next record */
+ if (len == -ENOENT)
+ goto skip;
+ else if (len < 0)
+ goto out;
+
+ 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);