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ACPI / tables: Move table override mechanisms to tables.c
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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>
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Lv Zheng authored and Rafael J. Wysocki committed Apr 18, 2016
1 parent c3b46c7 commit 5ae74f2
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Showing 5 changed files with 294 additions and 285 deletions.
2 changes: 1 addition & 1 deletion arch/x86/kernel/setup.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1139,7 +1139,7 @@ void __init setup_arch(char **cmdline_p)
reserve_initrd();

#if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
acpi_initrd_override((void *)initrd_start, initrd_end - initrd_start);
early_acpi_table_init((void *)initrd_start, initrd_end - initrd_start);
#endif

vsmp_init();
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1 change: 0 additions & 1 deletion drivers/acpi/internal.h
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Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,6 @@

#define PREFIX "ACPI: "

void acpi_initrd_initialize_tables(void);
acpi_status acpi_os_initialize1(void);
void init_acpi_device_notify(void);
int acpi_scan_init(void);
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274 changes: 0 additions & 274 deletions drivers/acpi/osl.c
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Original file line number Diff line number Diff line change
Expand Up @@ -602,280 +602,6 @@ acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
return AE_OK;
}

static void acpi_table_taint(struct acpi_table_header *table)
{
pr_warn(PREFIX
"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
#include <linux/earlycpio.h>
#include <linux/memblock.h>

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)

void __init acpi_initrd_override(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;
}
}
}

acpi_status
acpi_os_physical_table_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;
}

void __init acpi_initrd_initialize_tables(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
acpi_status
acpi_os_physical_table_override(struct acpi_table_header *existing_table,
acpi_physical_address *address,
u32 *table_length)
{
*table_length = 0;
*address = 0;
return AE_OK;
}

void __init acpi_initrd_initialize_tables(void)
{
}
#endif /* CONFIG_ACPI_INITRD_TABLE_OVERRIDE */

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;
}

static irqreturn_t acpi_irq(int irq, void *dev_id)
{
u32 handled;
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