diff options
author | Lv Zheng <lv.zheng@intel.com> | 2016-04-11 10:13:18 +0800 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-04-18 23:59:08 +0200 |
commit | 5ae74f2cc2f150c1a5cee54cabbd71dd0661285a (patch) | |
tree | c4cfbf622009554d44ca68a8c5efbaecd7dd4f69 /drivers/acpi/tables.c | |
parent | c3b46c73264b03000d1e18b22f5caf63332547c9 (diff) | |
download | linux-5ae74f2cc2f150c1a5cee54cabbd71dd0661285a.tar.gz linux-5ae74f2cc2f150c1a5cee54cabbd71dd0661285a.tar.bz2 linux-5ae74f2cc2f150c1a5cee54cabbd71dd0661285a.zip |
ACPI / tables: Move table override mechanisms to tables.c
This patch moves acpi_os_table_override() and
acpi_os_physical_table_override() to tables.c.
Along with the mechanisms, acpi_initrd_initialize_tables() is also moved to
tables.c to form a static function. The following functions are renamed
according to this change:
1. acpi_initrd_override() -> renamed to early_acpi_table_init(), which
invokes acpi_table_initrd_init()
2. acpi_os_physical_table_override() -> which invokes
acpi_table_initrd_override()
3. acpi_initialize_initrd_tables() -> renamed to acpi_table_initrd_scan()
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/tables.c')
-rw-r--r-- | drivers/acpi/tables.c | 292 |
1 files changed, 291 insertions, 1 deletions
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index f49c02442d65..2e74dbf45dd4 100644 --- a/drivers/acpi/tables.c +++ b/drivers/acpi/tables.c @@ -32,6 +32,8 @@ #include <linux/errno.h> #include <linux/acpi.h> #include <linux/bootmem.h> +#include <linux/earlycpio.h> +#include <linux/memblock.h> #include "internal.h" #define ACPI_MAX_TABLES 128 @@ -433,6 +435,294 @@ static void __init check_multiple_madt(void) return; } +static void acpi_table_taint(struct acpi_table_header *table) +{ + pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n", + table->signature, table->oem_table_id); + add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE); +} + +#ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE +static u64 acpi_tables_addr; +static int all_tables_size; + +/* Copied from acpica/tbutils.c:acpi_tb_checksum() */ +static u8 __init acpi_table_checksum(u8 *buffer, u32 length) +{ + u8 sum = 0; + u8 *end = buffer + length; + + while (buffer < end) + sum = (u8) (sum + *(buffer++)); + return sum; +} + +/* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */ +static const char * const table_sigs[] = { + ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ, + ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT, + ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF, + ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET, + ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI, + ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA, + ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT, + ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT, + ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, NULL }; + +#define ACPI_HEADER_SIZE sizeof(struct acpi_table_header) + +#define ACPI_OVERRIDE_TABLES 64 +static struct cpio_data __initdata acpi_initrd_files[ACPI_OVERRIDE_TABLES]; +static DECLARE_BITMAP(acpi_initrd_installed, ACPI_OVERRIDE_TABLES); + +#define MAP_CHUNK_SIZE (NR_FIX_BTMAPS << PAGE_SHIFT) + +static void __init acpi_table_initrd_init(void *data, size_t size) +{ + int sig, no, table_nr = 0, total_offset = 0; + long offset = 0; + struct acpi_table_header *table; + char cpio_path[32] = "kernel/firmware/acpi/"; + struct cpio_data file; + + if (data == NULL || size == 0) + return; + + for (no = 0; no < ACPI_OVERRIDE_TABLES; no++) { + file = find_cpio_data(cpio_path, data, size, &offset); + if (!file.data) + break; + + data += offset; + size -= offset; + + if (file.size < sizeof(struct acpi_table_header)) { + pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n", + cpio_path, file.name); + continue; + } + + table = file.data; + + for (sig = 0; table_sigs[sig]; sig++) + if (!memcmp(table->signature, table_sigs[sig], 4)) + break; + + if (!table_sigs[sig]) { + pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n", + cpio_path, file.name); + continue; + } + if (file.size != table->length) { + pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n", + cpio_path, file.name); + continue; + } + if (acpi_table_checksum(file.data, table->length)) { + pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n", + cpio_path, file.name); + continue; + } + + pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n", + table->signature, cpio_path, file.name, table->length); + + all_tables_size += table->length; + acpi_initrd_files[table_nr].data = file.data; + acpi_initrd_files[table_nr].size = file.size; + table_nr++; + } + if (table_nr == 0) + return; + + acpi_tables_addr = + memblock_find_in_range(0, max_low_pfn_mapped << PAGE_SHIFT, + all_tables_size, PAGE_SIZE); + if (!acpi_tables_addr) { + WARN_ON(1); + return; + } + /* + * Only calling e820_add_reserve does not work and the + * tables are invalid (memory got used) later. + * memblock_reserve works as expected and the tables won't get modified. + * But it's not enough on X86 because ioremap will + * complain later (used by acpi_os_map_memory) that the pages + * that should get mapped are not marked "reserved". + * Both memblock_reserve and e820_add_region (via arch_reserve_mem_area) + * works fine. + */ + memblock_reserve(acpi_tables_addr, all_tables_size); + arch_reserve_mem_area(acpi_tables_addr, all_tables_size); + + /* + * early_ioremap only can remap 256k one time. If we map all + * tables one time, we will hit the limit. Need to map chunks + * one by one during copying the same as that in relocate_initrd(). + */ + for (no = 0; no < table_nr; no++) { + unsigned char *src_p = acpi_initrd_files[no].data; + phys_addr_t size = acpi_initrd_files[no].size; + phys_addr_t dest_addr = acpi_tables_addr + total_offset; + phys_addr_t slop, clen; + char *dest_p; + + total_offset += size; + + while (size) { + slop = dest_addr & ~PAGE_MASK; + clen = size; + if (clen > MAP_CHUNK_SIZE - slop) + clen = MAP_CHUNK_SIZE - slop; + dest_p = early_ioremap(dest_addr & PAGE_MASK, + clen + slop); + memcpy(dest_p + slop, src_p, clen); + early_iounmap(dest_p, clen + slop); + src_p += clen; + dest_addr += clen; + size -= clen; + } + } +} + +static acpi_status +acpi_table_initrd_override(struct acpi_table_header *existing_table, + acpi_physical_address *address, u32 *length) +{ + int table_offset = 0; + int table_index = 0; + struct acpi_table_header *table; + u32 table_length; + + *length = 0; + *address = 0; + if (!acpi_tables_addr) + return AE_OK; + + while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) { + table = acpi_os_map_memory(acpi_tables_addr + table_offset, + ACPI_HEADER_SIZE); + if (table_offset + table->length > all_tables_size) { + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + WARN_ON(1); + return AE_OK; + } + + table_length = table->length; + + /* Only override tables matched */ + if (test_bit(table_index, acpi_initrd_installed) || + memcmp(existing_table->signature, table->signature, 4) || + memcmp(table->oem_table_id, existing_table->oem_table_id, + ACPI_OEM_TABLE_ID_SIZE)) { + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + goto next_table; + } + + *length = table_length; + *address = acpi_tables_addr + table_offset; + acpi_table_taint(existing_table); + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + set_bit(table_index, acpi_initrd_installed); + break; + +next_table: + table_offset += table_length; + table_index++; + } + return AE_OK; +} + +static void __init acpi_table_initrd_scan(void) +{ + int table_offset = 0; + int table_index = 0; + u32 table_length; + struct acpi_table_header *table; + + if (!acpi_tables_addr) + return; + + while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) { + table = acpi_os_map_memory(acpi_tables_addr + table_offset, + ACPI_HEADER_SIZE); + if (table_offset + table->length > all_tables_size) { + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + WARN_ON(1); + return; + } + + table_length = table->length; + + /* Skip RSDT/XSDT which should only be used for override */ + if (test_bit(table_index, acpi_initrd_installed) || + ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) || + ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) { + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + goto next_table; + } + + acpi_table_taint(table); + acpi_os_unmap_memory(table, ACPI_HEADER_SIZE); + acpi_install_table(acpi_tables_addr + table_offset, TRUE); + set_bit(table_index, acpi_initrd_installed); +next_table: + table_offset += table_length; + table_index++; + } +} +#else +static void __init acpi_table_initrd_init(void *data, size_t size) +{ +} + +static acpi_status +acpi_table_initrd_override(struct acpi_table_header *existing_table, + acpi_physical_address *address, + u32 *table_length) +{ + *table_length = 0; + *address = 0; + return AE_OK; +} + +static void __init acpi_table_initrd_scan(void) +{ +} +#endif /* CONFIG_ACPI_INITRD_TABLE_OVERRIDE */ + +acpi_status +acpi_os_physical_table_override(struct acpi_table_header *existing_table, + acpi_physical_address *address, + u32 *table_length) +{ + return acpi_table_initrd_override(existing_table, address, + table_length); +} + +acpi_status +acpi_os_table_override(struct acpi_table_header *existing_table, + struct acpi_table_header **new_table) +{ + if (!existing_table || !new_table) + return AE_BAD_PARAMETER; + + *new_table = NULL; + +#ifdef CONFIG_ACPI_CUSTOM_DSDT + if (strncmp(existing_table->signature, "DSDT", 4) == 0) + *new_table = (struct acpi_table_header *)AmlCode; +#endif + if (*new_table != NULL) + acpi_table_taint(existing_table); + return AE_OK; +} + +void __init early_acpi_table_init(void *data, size_t size) +{ + acpi_table_initrd_init(data, size); +} + /* * acpi_table_init() * @@ -457,7 +747,7 @@ int __init acpi_table_init(void) status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0); if (ACPI_FAILURE(status)) return -EINVAL; - acpi_initrd_initialize_tables(); + acpi_table_initrd_scan(); check_multiple_madt(); return 0; |