| /* | 
 |  * ACPI Error Record Serialization Table, ERST, Implementation | 
 |  * | 
 |  * ACPI ERST introduced in ACPI 4.0, June 16, 2009. | 
 |  * ACPI Platform Error Interfaces : Error Serialization | 
 |  * | 
 |  * Copyright (c) 2021 Oracle and/or its affiliates. | 
 |  * | 
 |  * SPDX-License-Identifier: GPL-2.0-or-later | 
 |  */ | 
 |  | 
 | #include "qemu/osdep.h" | 
 | #include "qapi/error.h" | 
 | #include "hw/qdev-core.h" | 
 | #include "system/memory.h" | 
 | #include "qom/object.h" | 
 | #include "hw/pci/pci_device.h" | 
 | #include "qom/object_interfaces.h" | 
 | #include "qemu/error-report.h" | 
 | #include "migration/vmstate.h" | 
 | #include "hw/qdev-properties.h" | 
 | #include "hw/acpi/acpi.h" | 
 | #include "hw/acpi/acpi-defs.h" | 
 | #include "hw/acpi/aml-build.h" | 
 | #include "hw/acpi/bios-linker-loader.h" | 
 | #include "system/address-spaces.h" | 
 | #include "system/hostmem.h" | 
 | #include "hw/acpi/erst.h" | 
 | #include "trace.h" | 
 |  | 
 | /* ACPI 4.0: Table 17-16 Serialization Actions */ | 
 | #define ACTION_BEGIN_WRITE_OPERATION         0x0 | 
 | #define ACTION_BEGIN_READ_OPERATION          0x1 | 
 | #define ACTION_BEGIN_CLEAR_OPERATION         0x2 | 
 | #define ACTION_END_OPERATION                 0x3 | 
 | #define ACTION_SET_RECORD_OFFSET             0x4 | 
 | #define ACTION_EXECUTE_OPERATION             0x5 | 
 | #define ACTION_CHECK_BUSY_STATUS             0x6 | 
 | #define ACTION_GET_COMMAND_STATUS            0x7 | 
 | #define ACTION_GET_RECORD_IDENTIFIER         0x8 | 
 | #define ACTION_SET_RECORD_IDENTIFIER         0x9 | 
 | #define ACTION_GET_RECORD_COUNT              0xA | 
 | #define ACTION_BEGIN_DUMMY_WRITE_OPERATION   0xB | 
 | #define ACTION_RESERVED                      0xC | 
 | #define ACTION_GET_ERROR_LOG_ADDRESS_RANGE   0xD | 
 | #define ACTION_GET_ERROR_LOG_ADDRESS_LENGTH  0xE | 
 | #define ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES 0xF | 
 | #define ACTION_GET_EXECUTE_OPERATION_TIMINGS 0x10 /* ACPI 6.3 */ | 
 |  | 
 | /* ACPI 4.0: Table 17-17 Command Status Definitions */ | 
 | #define STATUS_SUCCESS                0x00 | 
 | #define STATUS_NOT_ENOUGH_SPACE       0x01 | 
 | #define STATUS_HARDWARE_NOT_AVAILABLE 0x02 | 
 | #define STATUS_FAILED                 0x03 | 
 | #define STATUS_RECORD_STORE_EMPTY     0x04 | 
 | #define STATUS_RECORD_NOT_FOUND       0x05 | 
 |  | 
 | /* ACPI 4.0: Table 17-19 Serialization Instructions */ | 
 | #define INST_READ_REGISTER                 0x00 | 
 | #define INST_READ_REGISTER_VALUE           0x01 | 
 | #define INST_WRITE_REGISTER                0x02 | 
 | #define INST_WRITE_REGISTER_VALUE          0x03 | 
 | #define INST_NOOP                          0x04 | 
 | #define INST_LOAD_VAR1                     0x05 | 
 | #define INST_LOAD_VAR2                     0x06 | 
 | #define INST_STORE_VAR1                    0x07 | 
 | #define INST_ADD                           0x08 | 
 | #define INST_SUBTRACT                      0x09 | 
 | #define INST_ADD_VALUE                     0x0A | 
 | #define INST_SUBTRACT_VALUE                0x0B | 
 | #define INST_STALL                         0x0C | 
 | #define INST_STALL_WHILE_TRUE              0x0D | 
 | #define INST_SKIP_NEXT_INSTRUCTION_IF_TRUE 0x0E | 
 | #define INST_GOTO                          0x0F | 
 | #define INST_SET_SRC_ADDRESS_BASE          0x10 | 
 | #define INST_SET_DST_ADDRESS_BASE          0x11 | 
 | #define INST_MOVE_DATA                     0x12 | 
 |  | 
 | /* UEFI 2.1: Appendix N Common Platform Error Record */ | 
 | #define UEFI_CPER_RECORD_MIN_SIZE 128U | 
 | #define UEFI_CPER_RECORD_LENGTH_OFFSET 20U | 
 | #define UEFI_CPER_RECORD_ID_OFFSET 96U | 
 |  | 
 | /* | 
 |  * NOTE that when accessing CPER fields within a record, memcpy() | 
 |  * is utilized to avoid a possible misaligned access on the host. | 
 |  */ | 
 |  | 
 | /* | 
 |  * This implementation is an ACTION (cmd) and VALUE (data) | 
 |  * interface consisting of just two 64-bit registers. | 
 |  */ | 
 | #define ERST_REG_SIZE (16UL) | 
 | #define ERST_ACTION_OFFSET (0UL) /* action (cmd) */ | 
 | #define ERST_VALUE_OFFSET  (8UL) /* argument/value (data) */ | 
 |  | 
 | /* | 
 |  * ERST_RECORD_SIZE is the buffer size for exchanging ERST | 
 |  * record contents. Thus, it defines the maximum record size. | 
 |  * As this is mapped through a PCI BAR, it must be a power of | 
 |  * two and larger than UEFI_CPER_RECORD_MIN_SIZE. | 
 |  * The backing storage is divided into fixed size "slots", | 
 |  * each ERST_RECORD_SIZE in length, and each "slot" | 
 |  * storing a single record. No attempt at optimizing storage | 
 |  * through compression, compaction, etc is attempted. | 
 |  * NOTE that slot 0 is reserved for the backing storage header. | 
 |  * Depending upon the size of the backing storage, additional | 
 |  * slots will be part of the slot 0 header in order to account | 
 |  * for a record_id for each available remaining slot. | 
 |  */ | 
 | /* 8KiB records, not too small, not too big */ | 
 | #define ERST_RECORD_SIZE (8192UL) | 
 |  | 
 | #define ACPI_ERST_MEMDEV_PROP "memdev" | 
 | #define ACPI_ERST_RECORD_SIZE_PROP "record_size" | 
 |  | 
 | /* | 
 |  * From the ACPI ERST spec sections: | 
 |  * A record id of all 0s is used to indicate 'unspecified' record id. | 
 |  * A record id of all 1s is used to indicate empty or end. | 
 |  */ | 
 | #define ERST_UNSPECIFIED_RECORD_ID (0UL) | 
 | #define ERST_EMPTY_END_RECORD_ID (~0UL) | 
 |  | 
 | #define ERST_IS_VALID_RECORD_ID(rid) \ | 
 |     ((rid != ERST_UNSPECIFIED_RECORD_ID) && \ | 
 |      (rid != ERST_EMPTY_END_RECORD_ID)) | 
 |  | 
 | /* | 
 |  * Implementation-specific definitions and types. | 
 |  * Values are arbitrary and chosen for this implementation. | 
 |  * See erst.rst documentation for details. | 
 |  */ | 
 | #define ERST_EXECUTE_OPERATION_MAGIC 0x9CUL | 
 | #define ERST_STORE_MAGIC 0x524F545354535245UL /* ERSTSTOR */ | 
 | typedef struct { | 
 |     uint64_t magic; | 
 |     uint32_t record_size; | 
 |     uint32_t storage_offset; /* offset to record storage beyond header */ | 
 |     uint16_t version; | 
 |     uint16_t reserved; | 
 |     uint32_t record_count; | 
 |     uint64_t map[]; /* contains record_ids, and position indicates index */ | 
 | } __attribute__((packed)) ERSTStorageHeader; | 
 |  | 
 | /* | 
 |  * Object cast macro | 
 |  */ | 
 | #define ACPIERST(obj) \ | 
 |     OBJECT_CHECK(ERSTDeviceState, (obj), TYPE_ACPI_ERST) | 
 |  | 
 | /* | 
 |  * Main ERST device state structure | 
 |  */ | 
 | typedef struct { | 
 |     PCIDevice parent_obj; | 
 |  | 
 |     /* Backend storage */ | 
 |     HostMemoryBackend *hostmem; | 
 |     MemoryRegion *hostmem_mr; | 
 |     uint32_t storage_size; | 
 |     uint32_t default_record_size; | 
 |  | 
 |     /* Programming registers */ | 
 |     MemoryRegion iomem_mr; | 
 |  | 
 |     /* Exchange buffer */ | 
 |     MemoryRegion exchange_mr; | 
 |  | 
 |     /* Interface state */ | 
 |     uint8_t operation; | 
 |     uint8_t busy_status; | 
 |     uint8_t command_status; | 
 |     uint32_t record_offset; | 
 |     uint64_t reg_action; | 
 |     uint64_t reg_value; | 
 |     uint64_t record_identifier; | 
 |     ERSTStorageHeader *header; | 
 |     unsigned first_record_index; | 
 |     unsigned last_record_index; | 
 |     unsigned next_record_index; | 
 |  | 
 | } ERSTDeviceState; | 
 |  | 
 | /*******************************************************************/ | 
 | /*******************************************************************/ | 
 | typedef struct { | 
 |     GArray *table_data; | 
 |     pcibus_t bar; | 
 |     uint8_t instruction; | 
 |     uint8_t flags; | 
 |     uint8_t register_bit_width; | 
 |     pcibus_t register_offset; | 
 | } BuildSerializationInstructionEntry; | 
 |  | 
 | /* ACPI 4.0: 17.4.1.2 Serialization Instruction Entries */ | 
 | static void build_serialization_instruction( | 
 |     BuildSerializationInstructionEntry *e, | 
 |     uint8_t serialization_action, | 
 |     uint64_t value) | 
 | { | 
 |     /* ACPI 4.0: Table 17-18 Serialization Instruction Entry */ | 
 |     struct AcpiGenericAddress gas; | 
 |     uint64_t mask; | 
 |  | 
 |     /* Serialization Action */ | 
 |     build_append_int_noprefix(e->table_data, serialization_action, 1); | 
 |     /* Instruction */ | 
 |     build_append_int_noprefix(e->table_data, e->instruction, 1); | 
 |     /* Flags */ | 
 |     build_append_int_noprefix(e->table_data, e->flags, 1); | 
 |     /* Reserved */ | 
 |     build_append_int_noprefix(e->table_data, 0, 1); | 
 |     /* Register Region */ | 
 |     gas.space_id = AML_SYSTEM_MEMORY; | 
 |     gas.bit_width = e->register_bit_width; | 
 |     gas.bit_offset = 0; | 
 |     gas.access_width = (uint8_t)ctz32(e->register_bit_width) - 2; | 
 |     gas.address = (uint64_t)(e->bar + e->register_offset); | 
 |     build_append_gas_from_struct(e->table_data, &gas); | 
 |     /* Value */ | 
 |     build_append_int_noprefix(e->table_data, value, 8); | 
 |     /* Mask */ | 
 |     mask = (1ULL << (e->register_bit_width - 1) << 1) - 1; | 
 |     build_append_int_noprefix(e->table_data, mask, 8); | 
 | } | 
 |  | 
 | /* ACPI 4.0: 17.4.1 Serialization Action Table */ | 
 | void build_erst(GArray *table_data, BIOSLinker *linker, Object *erst_dev, | 
 |     const char *oem_id, const char *oem_table_id) | 
 | { | 
 |     /* | 
 |      * Serialization Action Table | 
 |      * The serialization action table must be generated first | 
 |      * so that its size can be known in order to populate the | 
 |      * Instruction Entry Count field. | 
 |      */ | 
 |     unsigned action; | 
 |     GArray *table_instruction_data = g_array_new(FALSE, FALSE, sizeof(char)); | 
 |     pcibus_t bar0 = pci_get_bar_addr(PCI_DEVICE(erst_dev), 0); | 
 |     AcpiTable table = { .sig = "ERST", .rev = 1, .oem_id = oem_id, | 
 |                         .oem_table_id = oem_table_id }; | 
 |     /* Contexts for the different ways ACTION and VALUE are accessed */ | 
 |     BuildSerializationInstructionEntry rd_value_32_val = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_READ_REGISTER_VALUE, | 
 |         .register_bit_width = 32, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry rd_value_32 = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_READ_REGISTER, | 
 |         .register_bit_width = 32, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry rd_value_64 = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_READ_REGISTER, | 
 |         .register_bit_width = 64, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry wr_value_32_val = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_WRITE_REGISTER_VALUE, | 
 |         .register_bit_width = 32, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry wr_value_32 = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_WRITE_REGISTER, | 
 |         .register_bit_width = 32, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry wr_value_64 = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_WRITE_REGISTER, | 
 |         .register_bit_width = 64, | 
 |         .register_offset = ERST_VALUE_OFFSET, | 
 |     }; | 
 |     BuildSerializationInstructionEntry wr_action = { | 
 |         .table_data = table_instruction_data, .bar = bar0, .flags = 0, | 
 |         .instruction = INST_WRITE_REGISTER_VALUE, | 
 |         .register_bit_width = 32, | 
 |         .register_offset = ERST_ACTION_OFFSET, | 
 |     }; | 
 |  | 
 |     trace_acpi_erst_pci_bar_0(bar0); | 
 |  | 
 |     /* Serialization Instruction Entries */ | 
 |     action = ACTION_BEGIN_WRITE_OPERATION; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_BEGIN_READ_OPERATION; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_BEGIN_CLEAR_OPERATION; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_END_OPERATION; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_SET_RECORD_OFFSET; | 
 |     build_serialization_instruction(&wr_value_32, action, 0); | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_EXECUTE_OPERATION; | 
 |     build_serialization_instruction(&wr_value_32_val, action, | 
 |         ERST_EXECUTE_OPERATION_MAGIC); | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_CHECK_BUSY_STATUS; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_32_val, action, 0x01); | 
 |  | 
 |     action = ACTION_GET_COMMAND_STATUS; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_32, action, 0); | 
 |  | 
 |     action = ACTION_GET_RECORD_IDENTIFIER; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_64, action, 0); | 
 |  | 
 |     action = ACTION_SET_RECORD_IDENTIFIER; | 
 |     build_serialization_instruction(&wr_value_64, action, 0); | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_GET_RECORD_COUNT; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_32, action, 0); | 
 |  | 
 |     action = ACTION_BEGIN_DUMMY_WRITE_OPERATION; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |  | 
 |     action = ACTION_GET_ERROR_LOG_ADDRESS_RANGE; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_64, action, 0); | 
 |  | 
 |     action = ACTION_GET_ERROR_LOG_ADDRESS_LENGTH; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_64, action, 0); | 
 |  | 
 |     action = ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_32, action, 0); | 
 |  | 
 |     action = ACTION_GET_EXECUTE_OPERATION_TIMINGS; | 
 |     build_serialization_instruction(&wr_action, action, action); | 
 |     build_serialization_instruction(&rd_value_64, action, 0); | 
 |  | 
 |     /* Serialization Header */ | 
 |     acpi_table_begin(&table, table_data); | 
 |  | 
 |     /* Serialization Header Size */ | 
 |     build_append_int_noprefix(table_data, 48, 4); | 
 |  | 
 |     /* Reserved */ | 
 |     build_append_int_noprefix(table_data,  0, 4); | 
 |  | 
 |     /* | 
 |      * Instruction Entry Count | 
 |      * Each instruction entry is 32 bytes | 
 |      */ | 
 |     g_assert((table_instruction_data->len) % 32 == 0); | 
 |     build_append_int_noprefix(table_data, | 
 |         (table_instruction_data->len / 32), 4); | 
 |  | 
 |     /* Serialization Instruction Entries */ | 
 |     g_array_append_vals(table_data, table_instruction_data->data, | 
 |         table_instruction_data->len); | 
 |     g_array_free(table_instruction_data, TRUE); | 
 |  | 
 |     acpi_table_end(linker, &table); | 
 | } | 
 |  | 
 | /*******************************************************************/ | 
 | /*******************************************************************/ | 
 | static uint8_t *get_nvram_ptr_by_index(ERSTDeviceState *s, unsigned index) | 
 | { | 
 |     uint8_t *rc = NULL; | 
 |     off_t offset = (index * le32_to_cpu(s->header->record_size)); | 
 |  | 
 |     g_assert(offset < s->storage_size); | 
 |  | 
 |     rc = memory_region_get_ram_ptr(s->hostmem_mr); | 
 |     rc += offset; | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | static void make_erst_storage_header(ERSTDeviceState *s) | 
 | { | 
 |     ERSTStorageHeader *header = s->header; | 
 |     unsigned mapsz, headersz; | 
 |  | 
 |     header->magic = cpu_to_le64(ERST_STORE_MAGIC); | 
 |     header->record_size = cpu_to_le32(s->default_record_size); | 
 |     header->version = cpu_to_le16(0x0100); | 
 |     header->reserved = cpu_to_le16(0x0000); | 
 |  | 
 |     /* Compute mapsize */ | 
 |     mapsz = s->storage_size / s->default_record_size; | 
 |     mapsz *= sizeof(uint64_t); | 
 |     /* Compute header+map size */ | 
 |     headersz = sizeof(ERSTStorageHeader) + mapsz; | 
 |     /* Round up to nearest integer multiple of ERST_RECORD_SIZE */ | 
 |     headersz = QEMU_ALIGN_UP(headersz, s->default_record_size); | 
 |     header->storage_offset = cpu_to_le32(headersz); | 
 |  | 
 |     /* | 
 |      * The HostMemoryBackend initializes contents to zero, | 
 |      * so all record_ids stashed in the map are zero'd. | 
 |      * As well the record_count is zero. Properly initialized. | 
 |      */ | 
 | } | 
 |  | 
 | static void check_erst_backend_storage(ERSTDeviceState *s, Error **errp) | 
 | { | 
 |     ERSTStorageHeader *header; | 
 |     uint32_t record_size; | 
 |  | 
 |     header = memory_region_get_ram_ptr(s->hostmem_mr); | 
 |     s->header = header; | 
 |  | 
 |     /* Ensure pointer to header is 64-bit aligned */ | 
 |     g_assert(QEMU_PTR_IS_ALIGNED(header, sizeof(uint64_t))); | 
 |  | 
 |     /* | 
 |      * Check if header is uninitialized; HostMemoryBackend inits to 0 | 
 |      */ | 
 |     if (le64_to_cpu(header->magic) == 0UL) { | 
 |         make_erst_storage_header(s); | 
 |     } | 
 |  | 
 |     /* Validity check record_size */ | 
 |     record_size = le32_to_cpu(header->record_size); | 
 |     if (!( | 
 |         (record_size) && /* non zero */ | 
 |         (record_size >= UEFI_CPER_RECORD_MIN_SIZE) && | 
 |         (((record_size - 1) & record_size) == 0) && /* is power of 2 */ | 
 |         (record_size >= 4096) /* PAGE_SIZE */ | 
 |         )) { | 
 |         error_setg(errp, "ERST record_size %u is invalid", record_size); | 
 |         return; | 
 |     } | 
 |  | 
 |     /* Validity check header */ | 
 |     if (!( | 
 |         (le64_to_cpu(header->magic) == ERST_STORE_MAGIC) && | 
 |         ((le32_to_cpu(header->storage_offset) % record_size) == 0) && | 
 |         (le16_to_cpu(header->version) == 0x0100) && | 
 |         (le16_to_cpu(header->reserved) == 0) | 
 |         )) { | 
 |         error_setg(errp, "ERST backend storage header is invalid"); | 
 |         return; | 
 |     } | 
 |  | 
 |     /* Check storage_size against record_size */ | 
 |     if (((s->storage_size % record_size) != 0) || | 
 |          (record_size > s->storage_size)) { | 
 |         error_setg(errp, "ACPI ERST requires storage size be multiple of " | 
 |             "record size (%uKiB)", record_size); | 
 |         return; | 
 |     } | 
 |  | 
 |     /* Compute offset of first and last record storage slot */ | 
 |     s->first_record_index = le32_to_cpu(header->storage_offset) | 
 |         / record_size; | 
 |     s->last_record_index = (s->storage_size / record_size); | 
 | } | 
 |  | 
 | static void update_map_entry(ERSTDeviceState *s, unsigned index, | 
 |     uint64_t record_id) | 
 | { | 
 |     if (index < s->last_record_index) { | 
 |         s->header->map[index] = cpu_to_le64(record_id); | 
 |     } | 
 | } | 
 |  | 
 | static unsigned find_next_empty_record_index(ERSTDeviceState *s) | 
 | { | 
 |     unsigned rc = 0; /* 0 not a valid index */ | 
 |     unsigned index = s->first_record_index; | 
 |  | 
 |     for (; index < s->last_record_index; ++index) { | 
 |         if (le64_to_cpu(s->header->map[index]) == ERST_UNSPECIFIED_RECORD_ID) { | 
 |             rc = index; | 
 |             break; | 
 |         } | 
 |     } | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | static unsigned lookup_erst_record(ERSTDeviceState *s, | 
 |     uint64_t record_identifier) | 
 | { | 
 |     unsigned rc = 0; /* 0 not a valid index */ | 
 |  | 
 |     /* Find the record_identifier in the map */ | 
 |     if (record_identifier != ERST_UNSPECIFIED_RECORD_ID) { | 
 |         /* | 
 |          * Count number of valid records encountered, and | 
 |          * short-circuit the loop if identifier not found | 
 |          */ | 
 |         uint32_t record_count = le32_to_cpu(s->header->record_count); | 
 |         unsigned count = 0; | 
 |         unsigned index; | 
 |         for (index = s->first_record_index; index < s->last_record_index && | 
 |                 count < record_count; ++index) { | 
 |             if (le64_to_cpu(s->header->map[index]) == record_identifier) { | 
 |                 rc = index; | 
 |                 break; | 
 |             } | 
 |             if (le64_to_cpu(s->header->map[index]) != | 
 |                 ERST_UNSPECIFIED_RECORD_ID) { | 
 |                 ++count; | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | /* | 
 |  * ACPI 4.0: 17.4.1.1 Serialization Actions, also see | 
 |  * ACPI 4.0: 17.4.2.2 Operations - Reading 6.c and 2.c | 
 |  */ | 
 | static unsigned get_next_record_identifier(ERSTDeviceState *s, | 
 |     uint64_t *record_identifier, bool first) | 
 | { | 
 |     unsigned found = 0; | 
 |     unsigned index; | 
 |  | 
 |     /* For operations needing to return 'first' record identifier */ | 
 |     if (first) { | 
 |         /* Reset initial index to beginning */ | 
 |         s->next_record_index = s->first_record_index; | 
 |     } | 
 |     index = s->next_record_index; | 
 |  | 
 |     *record_identifier = ERST_EMPTY_END_RECORD_ID; | 
 |  | 
 |     if (le32_to_cpu(s->header->record_count)) { | 
 |         for (; index < s->last_record_index; ++index) { | 
 |             if (le64_to_cpu(s->header->map[index]) != | 
 |                     ERST_UNSPECIFIED_RECORD_ID) { | 
 |                     /* where to start next time */ | 
 |                     s->next_record_index = index + 1; | 
 |                     *record_identifier = le64_to_cpu(s->header->map[index]); | 
 |                     found = 1; | 
 |                     break; | 
 |             } | 
 |         } | 
 |     } | 
 |     if (!found) { | 
 |         /* at end (ie scan complete), reset */ | 
 |         s->next_record_index = s->first_record_index; | 
 |     } | 
 |  | 
 |     return STATUS_SUCCESS; | 
 | } | 
 |  | 
 | /* ACPI 4.0: 17.4.2.3 Operations - Clearing */ | 
 | static unsigned clear_erst_record(ERSTDeviceState *s) | 
 | { | 
 |     unsigned rc = STATUS_RECORD_NOT_FOUND; | 
 |     unsigned index; | 
 |  | 
 |     /* Check for valid record identifier */ | 
 |     if (!ERST_IS_VALID_RECORD_ID(s->record_identifier)) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     index = lookup_erst_record(s, s->record_identifier); | 
 |     if (index) { | 
 |         /* No need to wipe record, just invalidate its map entry */ | 
 |         uint32_t record_count; | 
 |         update_map_entry(s, index, ERST_UNSPECIFIED_RECORD_ID); | 
 |         record_count = le32_to_cpu(s->header->record_count); | 
 |         record_count -= 1; | 
 |         s->header->record_count = cpu_to_le32(record_count); | 
 |         rc = STATUS_SUCCESS; | 
 |     } | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | /* ACPI 4.0: 17.4.2.2 Operations - Reading */ | 
 | static unsigned read_erst_record(ERSTDeviceState *s) | 
 | { | 
 |     unsigned rc = STATUS_RECORD_NOT_FOUND; | 
 |     unsigned exchange_length; | 
 |     unsigned index; | 
 |  | 
 |     /* Check if backend storage is empty */ | 
 |     if (le32_to_cpu(s->header->record_count) == 0) { | 
 |         return STATUS_RECORD_STORE_EMPTY; | 
 |     } | 
 |  | 
 |     exchange_length = memory_region_size(&s->exchange_mr); | 
 |  | 
 |     /* Check for record identifier of all 0s */ | 
 |     if (s->record_identifier == ERST_UNSPECIFIED_RECORD_ID) { | 
 |         /* Set to 'first' record in storage */ | 
 |         get_next_record_identifier(s, &s->record_identifier, true); | 
 |         /* record_identifier is now a valid id, or all 1s */ | 
 |     } | 
 |  | 
 |     /* Check for record identifier of all 1s */ | 
 |     if (s->record_identifier == ERST_EMPTY_END_RECORD_ID) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     /* Validate record_offset */ | 
 |     if (s->record_offset > (exchange_length - UEFI_CPER_RECORD_MIN_SIZE)) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     index = lookup_erst_record(s, s->record_identifier); | 
 |     if (index) { | 
 |         uint8_t *nvram; | 
 |         uint8_t *exchange; | 
 |         uint32_t record_length; | 
 |  | 
 |         /* Obtain pointer to the exchange buffer */ | 
 |         exchange = memory_region_get_ram_ptr(&s->exchange_mr); | 
 |         exchange += s->record_offset; | 
 |         /* Obtain pointer to slot in storage */ | 
 |         nvram = get_nvram_ptr_by_index(s, index); | 
 |         /* Validate CPER record_length */ | 
 |         memcpy((uint8_t *)&record_length, | 
 |             &nvram[UEFI_CPER_RECORD_LENGTH_OFFSET], | 
 |             sizeof(uint32_t)); | 
 |         record_length = le32_to_cpu(record_length); | 
 |         if (record_length < UEFI_CPER_RECORD_MIN_SIZE) { | 
 |             rc = STATUS_FAILED; | 
 |         } | 
 |         if (record_length > exchange_length - s->record_offset) { | 
 |             rc = STATUS_FAILED; | 
 |         } | 
 |         /* If all is ok, copy the record to the exchange buffer */ | 
 |         if (rc != STATUS_FAILED) { | 
 |             memcpy(exchange, nvram, record_length); | 
 |             rc = STATUS_SUCCESS; | 
 |         } | 
 |     } else { | 
 |         /* | 
 |          * See "Reading : 'The steps performed by the platform ...' 2.c" | 
 |          * Set to 'first' record in storage | 
 |          */ | 
 |         get_next_record_identifier(s, &s->record_identifier, true); | 
 |     } | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | /* ACPI 4.0: 17.4.2.1 Operations - Writing */ | 
 | static unsigned write_erst_record(ERSTDeviceState *s) | 
 | { | 
 |     unsigned rc = STATUS_FAILED; | 
 |     unsigned exchange_length; | 
 |     unsigned index; | 
 |     uint64_t record_identifier; | 
 |     uint32_t record_length; | 
 |     uint8_t *exchange; | 
 |     uint8_t *nvram = NULL; | 
 |     bool record_found = false; | 
 |  | 
 |     exchange_length = memory_region_size(&s->exchange_mr); | 
 |  | 
 |     /* Validate record_offset */ | 
 |     if (s->record_offset > (exchange_length - UEFI_CPER_RECORD_MIN_SIZE)) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     /* Obtain pointer to record in the exchange buffer */ | 
 |     exchange = memory_region_get_ram_ptr(&s->exchange_mr); | 
 |     exchange += s->record_offset; | 
 |  | 
 |     /* Validate CPER record_length */ | 
 |     memcpy((uint8_t *)&record_length, &exchange[UEFI_CPER_RECORD_LENGTH_OFFSET], | 
 |         sizeof(uint32_t)); | 
 |     record_length = le32_to_cpu(record_length); | 
 |     if (record_length < UEFI_CPER_RECORD_MIN_SIZE) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |     if (record_length > exchange_length - s->record_offset) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     /* Extract record identifier */ | 
 |     memcpy((uint8_t *)&record_identifier, &exchange[UEFI_CPER_RECORD_ID_OFFSET], | 
 |         sizeof(uint64_t)); | 
 |     record_identifier = le64_to_cpu(record_identifier); | 
 |  | 
 |     /* Check for valid record identifier */ | 
 |     if (!ERST_IS_VALID_RECORD_ID(record_identifier)) { | 
 |         return STATUS_FAILED; | 
 |     } | 
 |  | 
 |     index = lookup_erst_record(s, record_identifier); | 
 |     if (index) { | 
 |         /* Record found, overwrite existing record */ | 
 |         nvram = get_nvram_ptr_by_index(s, index); | 
 |         record_found = true; | 
 |     } else { | 
 |         /* Record not found, not an overwrite, allocate for write */ | 
 |         index = find_next_empty_record_index(s); | 
 |         if (index) { | 
 |             nvram = get_nvram_ptr_by_index(s, index); | 
 |         } else { | 
 |             /* All slots are occupied */ | 
 |             rc = STATUS_NOT_ENOUGH_SPACE; | 
 |         } | 
 |     } | 
 |     if (nvram) { | 
 |         /* Write the record into the slot */ | 
 |         memcpy(nvram, exchange, record_length); | 
 |         memset(nvram + record_length, 0xFF, exchange_length - record_length); | 
 |         /* If a new record, increment the record_count */ | 
 |         if (!record_found) { | 
 |             uint32_t record_count; | 
 |             record_count = le32_to_cpu(s->header->record_count); | 
 |             record_count += 1; /* writing new record */ | 
 |             s->header->record_count = cpu_to_le32(record_count); | 
 |         } | 
 |         update_map_entry(s, index, record_identifier); | 
 |         rc = STATUS_SUCCESS; | 
 |     } | 
 |  | 
 |     return rc; | 
 | } | 
 |  | 
 | /*******************************************************************/ | 
 |  | 
 | static uint64_t erst_rd_reg64(hwaddr addr, | 
 |     uint64_t reg, unsigned size) | 
 | { | 
 |     uint64_t rdval; | 
 |     uint64_t mask; | 
 |     unsigned shift; | 
 |  | 
 |     if (size == sizeof(uint64_t)) { | 
 |         /* 64b access */ | 
 |         mask = 0xFFFFFFFFFFFFFFFFUL; | 
 |         shift = 0; | 
 |     } else { | 
 |         /* 32b access */ | 
 |         mask = 0x00000000FFFFFFFFUL; | 
 |         shift = ((addr & 0x4) == 0x4) ? 32 : 0; | 
 |     } | 
 |  | 
 |     rdval = reg; | 
 |     rdval >>= shift; | 
 |     rdval &= mask; | 
 |  | 
 |     return rdval; | 
 | } | 
 |  | 
 | static uint64_t erst_wr_reg64(hwaddr addr, | 
 |     uint64_t reg, uint64_t val, unsigned size) | 
 | { | 
 |     uint64_t wrval; | 
 |     uint64_t mask; | 
 |     unsigned shift; | 
 |  | 
 |     if (size == sizeof(uint64_t)) { | 
 |         /* 64b access */ | 
 |         mask = 0xFFFFFFFFFFFFFFFFUL; | 
 |         shift = 0; | 
 |     } else { | 
 |         /* 32b access */ | 
 |         mask = 0x00000000FFFFFFFFUL; | 
 |         shift = ((addr & 0x4) == 0x4) ? 32 : 0; | 
 |     } | 
 |  | 
 |     val &= mask; | 
 |     val <<= shift; | 
 |     mask <<= shift; | 
 |     wrval = reg; | 
 |     wrval &= ~mask; | 
 |     wrval |= val; | 
 |  | 
 |     return wrval; | 
 | } | 
 |  | 
 | static void erst_reg_write(void *opaque, hwaddr addr, | 
 |     uint64_t val, unsigned size) | 
 | { | 
 |     ERSTDeviceState *s = (ERSTDeviceState *)opaque; | 
 |  | 
 |     /* | 
 |      * NOTE: All actions/operations/side effects happen on the WRITE, | 
 |      * by this implementation's design. The READs simply return the | 
 |      * reg_value contents. | 
 |      */ | 
 |     trace_acpi_erst_reg_write(addr, val, size); | 
 |  | 
 |     switch (addr) { | 
 |     case ERST_VALUE_OFFSET + 0: | 
 |     case ERST_VALUE_OFFSET + 4: | 
 |         s->reg_value = erst_wr_reg64(addr, s->reg_value, val, size); | 
 |         break; | 
 |     case ERST_ACTION_OFFSET + 0: | 
 |         /* | 
 |          * NOTE: all valid values written to this register are of the | 
 |          * ACTION_* variety. Thus there is no need to make this a 64-bit | 
 |          * register, 32-bits is appropriate. As such ERST_ACTION_OFFSET+4 | 
 |          * is not needed. | 
 |          */ | 
 |         switch (val) { | 
 |         case ACTION_BEGIN_WRITE_OPERATION: | 
 |         case ACTION_BEGIN_READ_OPERATION: | 
 |         case ACTION_BEGIN_CLEAR_OPERATION: | 
 |         case ACTION_BEGIN_DUMMY_WRITE_OPERATION: | 
 |         case ACTION_END_OPERATION: | 
 |             s->operation = val; | 
 |             break; | 
 |         case ACTION_SET_RECORD_OFFSET: | 
 |             s->record_offset = s->reg_value; | 
 |             break; | 
 |         case ACTION_EXECUTE_OPERATION: | 
 |             if ((uint8_t)s->reg_value == ERST_EXECUTE_OPERATION_MAGIC) { | 
 |                 s->busy_status = 1; | 
 |                 switch (s->operation) { | 
 |                 case ACTION_BEGIN_WRITE_OPERATION: | 
 |                     s->command_status = write_erst_record(s); | 
 |                     break; | 
 |                 case ACTION_BEGIN_READ_OPERATION: | 
 |                     s->command_status = read_erst_record(s); | 
 |                     break; | 
 |                 case ACTION_BEGIN_CLEAR_OPERATION: | 
 |                     s->command_status = clear_erst_record(s); | 
 |                     break; | 
 |                 case ACTION_BEGIN_DUMMY_WRITE_OPERATION: | 
 |                     s->command_status = STATUS_SUCCESS; | 
 |                     break; | 
 |                 case ACTION_END_OPERATION: | 
 |                     s->command_status = STATUS_SUCCESS; | 
 |                     break; | 
 |                 default: | 
 |                     s->command_status = STATUS_FAILED; | 
 |                     break; | 
 |                 } | 
 |                 s->busy_status = 0; | 
 |             } | 
 |             break; | 
 |         case ACTION_CHECK_BUSY_STATUS: | 
 |             s->reg_value = s->busy_status; | 
 |             break; | 
 |         case ACTION_GET_COMMAND_STATUS: | 
 |             s->reg_value = s->command_status; | 
 |             break; | 
 |         case ACTION_GET_RECORD_IDENTIFIER: | 
 |             s->command_status = get_next_record_identifier(s, | 
 |                                     &s->reg_value, false); | 
 |             break; | 
 |         case ACTION_SET_RECORD_IDENTIFIER: | 
 |             s->record_identifier = s->reg_value; | 
 |             break; | 
 |         case ACTION_GET_RECORD_COUNT: | 
 |             s->reg_value = le32_to_cpu(s->header->record_count); | 
 |             break; | 
 |         case ACTION_GET_ERROR_LOG_ADDRESS_RANGE: | 
 |             s->reg_value = (hwaddr)pci_get_bar_addr(PCI_DEVICE(s), 1); | 
 |             break; | 
 |         case ACTION_GET_ERROR_LOG_ADDRESS_LENGTH: | 
 |             s->reg_value = le32_to_cpu(s->header->record_size); | 
 |             break; | 
 |         case ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES: | 
 |             s->reg_value = 0x0; /* intentional, not NVRAM mode */ | 
 |             break; | 
 |         case ACTION_GET_EXECUTE_OPERATION_TIMINGS: | 
 |             s->reg_value = | 
 |                 (100ULL << 32) | /* 100us max time */ | 
 |                 (10ULL  <<  0) ; /*  10us min time */ | 
 |             break; | 
 |         default: | 
 |             /* Unknown action/command, NOP */ | 
 |             break; | 
 |         } | 
 |         break; | 
 |     default: | 
 |         /* This should not happen, but if it does, NOP */ | 
 |         break; | 
 |     } | 
 | } | 
 |  | 
 | static uint64_t erst_reg_read(void *opaque, hwaddr addr, | 
 |                                 unsigned size) | 
 | { | 
 |     ERSTDeviceState *s = (ERSTDeviceState *)opaque; | 
 |     uint64_t val = 0; | 
 |  | 
 |     switch (addr) { | 
 |     case ERST_ACTION_OFFSET + 0: | 
 |     case ERST_ACTION_OFFSET + 4: | 
 |         val = erst_rd_reg64(addr, s->reg_action, size); | 
 |         break; | 
 |     case ERST_VALUE_OFFSET + 0: | 
 |     case ERST_VALUE_OFFSET + 4: | 
 |         val = erst_rd_reg64(addr, s->reg_value, size); | 
 |         break; | 
 |     default: | 
 |         break; | 
 |     } | 
 |     trace_acpi_erst_reg_read(addr, val, size); | 
 |     return val; | 
 | } | 
 |  | 
 | static const MemoryRegionOps erst_reg_ops = { | 
 |     .read = erst_reg_read, | 
 |     .write = erst_reg_write, | 
 |     .endianness = DEVICE_NATIVE_ENDIAN, | 
 | }; | 
 |  | 
 | /*******************************************************************/ | 
 | /*******************************************************************/ | 
 | static int erst_post_load(void *opaque, int version_id) | 
 | { | 
 |     ERSTDeviceState *s = opaque; | 
 |  | 
 |     /* Recompute pointer to header */ | 
 |     s->header = (ERSTStorageHeader *)get_nvram_ptr_by_index(s, 0); | 
 |     trace_acpi_erst_post_load(s->header, le32_to_cpu(s->header->record_size)); | 
 |  | 
 |     return 0; | 
 | } | 
 |  | 
 | static const VMStateDescription erst_vmstate  = { | 
 |     .name = "acpi-erst", | 
 |     .version_id = 1, | 
 |     .minimum_version_id = 1, | 
 |     .post_load = erst_post_load, | 
 |     .fields = (const VMStateField[]) { | 
 |         VMSTATE_UINT8(operation, ERSTDeviceState), | 
 |         VMSTATE_UINT8(busy_status, ERSTDeviceState), | 
 |         VMSTATE_UINT8(command_status, ERSTDeviceState), | 
 |         VMSTATE_UINT32(record_offset, ERSTDeviceState), | 
 |         VMSTATE_UINT64(reg_action, ERSTDeviceState), | 
 |         VMSTATE_UINT64(reg_value, ERSTDeviceState), | 
 |         VMSTATE_UINT64(record_identifier, ERSTDeviceState), | 
 |         VMSTATE_UINT32(next_record_index, ERSTDeviceState), | 
 |         VMSTATE_END_OF_LIST() | 
 |     } | 
 | }; | 
 |  | 
 | static void erst_realizefn(PCIDevice *pci_dev, Error **errp) | 
 | { | 
 |     ERRP_GUARD(); | 
 |     ERSTDeviceState *s = ACPIERST(pci_dev); | 
 |  | 
 |     trace_acpi_erst_realizefn_in(); | 
 |  | 
 |     if (!s->hostmem) { | 
 |         error_setg(errp, "'" ACPI_ERST_MEMDEV_PROP "' property is not set"); | 
 |         return; | 
 |     } else if (host_memory_backend_is_mapped(s->hostmem)) { | 
 |         error_setg(errp, "can't use already busy memdev: %s", | 
 |                    object_get_canonical_path_component(OBJECT(s->hostmem))); | 
 |         return; | 
 |     } | 
 |  | 
 |     s->hostmem_mr = host_memory_backend_get_memory(s->hostmem); | 
 |  | 
 |     /* HostMemoryBackend size will be multiple of PAGE_SIZE */ | 
 |     s->storage_size = object_property_get_int(OBJECT(s->hostmem), "size", errp); | 
 |     if (*errp) { | 
 |         return; | 
 |     } | 
 |  | 
 |     /* Initialize backend storage and record_count */ | 
 |     check_erst_backend_storage(s, errp); | 
 |     if (*errp) { | 
 |         return; | 
 |     } | 
 |  | 
 |     /* BAR 0: Programming registers */ | 
 |     memory_region_init_io(&s->iomem_mr, OBJECT(pci_dev), &erst_reg_ops, s, | 
 |                           TYPE_ACPI_ERST, ERST_REG_SIZE); | 
 |     pci_register_bar(pci_dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->iomem_mr); | 
 |  | 
 |     /* BAR 1: Exchange buffer memory */ | 
 |     memory_region_init_ram(&s->exchange_mr, OBJECT(pci_dev), | 
 |                             "erst.exchange", | 
 |                             le32_to_cpu(s->header->record_size), errp); | 
 |     if (*errp) { | 
 |         return; | 
 |     } | 
 |     pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, | 
 |                         &s->exchange_mr); | 
 |  | 
 |     /* Include the backend storage in the migration stream */ | 
 |     vmstate_register_ram_global(s->hostmem_mr); | 
 |  | 
 |     trace_acpi_erst_realizefn_out(s->storage_size); | 
 | } | 
 |  | 
 | static void erst_reset(DeviceState *dev) | 
 | { | 
 |     ERSTDeviceState *s = ACPIERST(dev); | 
 |  | 
 |     trace_acpi_erst_reset_in(le32_to_cpu(s->header->record_count)); | 
 |     s->operation = 0; | 
 |     s->busy_status = 0; | 
 |     s->command_status = STATUS_SUCCESS; | 
 |     s->record_identifier = ERST_UNSPECIFIED_RECORD_ID; | 
 |     s->record_offset = 0; | 
 |     s->next_record_index = s->first_record_index; | 
 |     /* NOTE: first/last_record_index are computed only once */ | 
 |     trace_acpi_erst_reset_out(le32_to_cpu(s->header->record_count)); | 
 | } | 
 |  | 
 | static const Property erst_properties[] = { | 
 |     DEFINE_PROP_LINK(ACPI_ERST_MEMDEV_PROP, ERSTDeviceState, hostmem, | 
 |                      TYPE_MEMORY_BACKEND, HostMemoryBackend *), | 
 |     DEFINE_PROP_UINT32(ACPI_ERST_RECORD_SIZE_PROP, ERSTDeviceState, | 
 |                      default_record_size, ERST_RECORD_SIZE), | 
 | }; | 
 |  | 
 | static void erst_class_init(ObjectClass *klass, const void *data) | 
 | { | 
 |     DeviceClass *dc = DEVICE_CLASS(klass); | 
 |     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); | 
 |  | 
 |     trace_acpi_erst_class_init_in(); | 
 |     k->realize = erst_realizefn; | 
 |     k->vendor_id = PCI_VENDOR_ID_REDHAT; | 
 |     k->device_id = PCI_DEVICE_ID_REDHAT_ACPI_ERST; | 
 |     k->revision = 0x00; | 
 |     k->class_id = PCI_CLASS_OTHERS; | 
 |     device_class_set_legacy_reset(dc, erst_reset); | 
 |     dc->vmsd = &erst_vmstate; | 
 |     dc->user_creatable = true; | 
 |     dc->hotpluggable = false; | 
 |     device_class_set_props(dc, erst_properties); | 
 |     dc->desc = "ACPI Error Record Serialization Table (ERST) device"; | 
 |     set_bit(DEVICE_CATEGORY_MISC, dc->categories); | 
 |     trace_acpi_erst_class_init_out(); | 
 | } | 
 |  | 
 | static const TypeInfo erst_type_info = { | 
 |     .name          = TYPE_ACPI_ERST, | 
 |     .parent        = TYPE_PCI_DEVICE, | 
 |     .class_init    = erst_class_init, | 
 |     .instance_size = sizeof(ERSTDeviceState), | 
 |     .interfaces = (const InterfaceInfo[]) { | 
 |         { INTERFACE_CONVENTIONAL_PCI_DEVICE }, | 
 |         { } | 
 |     } | 
 | }; | 
 |  | 
 | static void erst_register_types(void) | 
 | { | 
 |     type_register_static(&erst_type_info); | 
 | } | 
 |  | 
 | type_init(erst_register_types) |