u-boot/lib/efi_loader/efi_memory.c
Maxim Uvarov ffbeafe7e2 efi_memory: refine overlap_only_ram description
Refine text for overlap_only_ram description to
match to what exactly flag does and aling description
with other functions.

Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-09-18 22:23:58 +02:00

816 lines
21 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* EFI application memory management
*
* Copyright (c) 2016 Alexander Graf
*/
#include <common.h>
#include <efi_loader.h>
#include <init.h>
#include <malloc.h>
#include <mapmem.h>
#include <watchdog.h>
#include <asm/cache.h>
#include <linux/list_sort.h>
#include <linux/sizes.h>
DECLARE_GLOBAL_DATA_PTR;
/* Magic number identifying memory allocated from pool */
#define EFI_ALLOC_POOL_MAGIC 0x1fe67ddf6491caa2
efi_uintn_t efi_memory_map_key;
struct efi_mem_list {
struct list_head link;
struct efi_mem_desc desc;
};
#define EFI_CARVE_NO_OVERLAP -1
#define EFI_CARVE_LOOP_AGAIN -2
#define EFI_CARVE_OVERLAPS_NONRAM -3
/* This list contains all memory map items */
LIST_HEAD(efi_mem);
#ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
void *efi_bounce_buffer;
#endif
/**
* struct efi_pool_allocation - memory block allocated from pool
*
* @num_pages: number of pages allocated
* @checksum: checksum
* @data: allocated pool memory
*
* U-Boot services each UEFI AllocatePool() request as a separate
* (multiple) page allocation. We have to track the number of pages
* to be able to free the correct amount later.
*
* The checksum calculated in function checksum() is used in FreePool() to avoid
* freeing memory not allocated by AllocatePool() and duplicate freeing.
*
* EFI requires 8 byte alignment for pool allocations, so we can
* prepend each allocation with these header fields.
*/
struct efi_pool_allocation {
u64 num_pages;
u64 checksum;
char data[] __aligned(ARCH_DMA_MINALIGN);
};
/**
* checksum() - calculate checksum for memory allocated from pool
*
* @alloc: allocation header
* Return: checksum, always non-zero
*/
static u64 checksum(struct efi_pool_allocation *alloc)
{
u64 addr = (uintptr_t)alloc;
u64 ret = (addr >> 32) ^ (addr << 32) ^ alloc->num_pages ^
EFI_ALLOC_POOL_MAGIC;
if (!ret)
++ret;
return ret;
}
/*
* Sorts the memory list from highest address to lowest address
*
* When allocating memory we should always start from the highest
* address chunk, so sort the memory list such that the first list
* iterator gets the highest address and goes lower from there.
*/
static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b)
{
struct efi_mem_list *mema = list_entry(a, struct efi_mem_list, link);
struct efi_mem_list *memb = list_entry(b, struct efi_mem_list, link);
if (mema->desc.physical_start == memb->desc.physical_start)
return 0;
else if (mema->desc.physical_start < memb->desc.physical_start)
return 1;
else
return -1;
}
static uint64_t desc_get_end(struct efi_mem_desc *desc)
{
return desc->physical_start + (desc->num_pages << EFI_PAGE_SHIFT);
}
static void efi_mem_sort(void)
{
struct list_head *lhandle;
struct efi_mem_list *prevmem = NULL;
bool merge_again = true;
list_sort(NULL, &efi_mem, efi_mem_cmp);
/* Now merge entries that can be merged */
while (merge_again) {
merge_again = false;
list_for_each(lhandle, &efi_mem) {
struct efi_mem_list *lmem;
struct efi_mem_desc *prev = &prevmem->desc;
struct efi_mem_desc *cur;
uint64_t pages;
lmem = list_entry(lhandle, struct efi_mem_list, link);
if (!prevmem) {
prevmem = lmem;
continue;
}
cur = &lmem->desc;
if ((desc_get_end(cur) == prev->physical_start) &&
(prev->type == cur->type) &&
(prev->attribute == cur->attribute)) {
/* There is an existing map before, reuse it */
pages = cur->num_pages;
prev->num_pages += pages;
prev->physical_start -= pages << EFI_PAGE_SHIFT;
prev->virtual_start -= pages << EFI_PAGE_SHIFT;
list_del(&lmem->link);
free(lmem);
merge_again = true;
break;
}
prevmem = lmem;
}
}
}
/** efi_mem_carve_out - unmap memory region
*
* @map: memory map
* @carve_desc: memory region to unmap
* @overlap_only_ram: the carved out region may only overlap RAM
* Return Value: the number of overlapping pages which have been
* removed from the map,
* EFI_CARVE_NO_OVERLAP, if the regions don't overlap,
* EFI_CARVE_OVERLAPS_NONRAM, if the carve and map overlap,
* and the map contains anything but free ram
* (only when overlap_only_ram is true),
* EFI_CARVE_LOOP_AGAIN, if the mapping list should be
* traversed again, as it has been altered.
*
* Unmaps all memory occupied by the carve_desc region from the list entry
* pointed to by map.
*
* In case of EFI_CARVE_OVERLAPS_NONRAM it is the callers responsibility
* to re-add the already carved out pages to the mapping.
*/
static s64 efi_mem_carve_out(struct efi_mem_list *map,
struct efi_mem_desc *carve_desc,
bool overlap_only_ram)
{
struct efi_mem_list *newmap;
struct efi_mem_desc *map_desc = &map->desc;
uint64_t map_start = map_desc->physical_start;
uint64_t map_end = map_start + (map_desc->num_pages << EFI_PAGE_SHIFT);
uint64_t carve_start = carve_desc->physical_start;
uint64_t carve_end = carve_start +
(carve_desc->num_pages << EFI_PAGE_SHIFT);
/* check whether we're overlapping */
if ((carve_end <= map_start) || (carve_start >= map_end))
return EFI_CARVE_NO_OVERLAP;
/* We're overlapping with non-RAM, warn the caller if desired */
if (overlap_only_ram && (map_desc->type != EFI_CONVENTIONAL_MEMORY))
return EFI_CARVE_OVERLAPS_NONRAM;
/* Sanitize carve_start and carve_end to lie within our bounds */
carve_start = max(carve_start, map_start);
carve_end = min(carve_end, map_end);
/* Carving at the beginning of our map? Just move it! */
if (carve_start == map_start) {
if (map_end == carve_end) {
/* Full overlap, just remove map */
list_del(&map->link);
free(map);
} else {
map->desc.physical_start = carve_end;
map->desc.virtual_start = carve_end;
map->desc.num_pages = (map_end - carve_end)
>> EFI_PAGE_SHIFT;
}
return (carve_end - carve_start) >> EFI_PAGE_SHIFT;
}
/*
* Overlapping maps, just split the list map at carve_start,
* it will get moved or removed in the next iteration.
*
* [ map_desc |__carve_start__| newmap ]
*/
/* Create a new map from [ carve_start ... map_end ] */
newmap = calloc(1, sizeof(*newmap));
newmap->desc = map->desc;
newmap->desc.physical_start = carve_start;
newmap->desc.virtual_start = carve_start;
newmap->desc.num_pages = (map_end - carve_start) >> EFI_PAGE_SHIFT;
/* Insert before current entry (descending address order) */
list_add_tail(&newmap->link, &map->link);
/* Shrink the map to [ map_start ... carve_start ] */
map_desc->num_pages = (carve_start - map_start) >> EFI_PAGE_SHIFT;
return EFI_CARVE_LOOP_AGAIN;
}
/**
* efi_add_memory_map_pg() - add pages to the memory map
*
* @start: start address, must be a multiple of EFI_PAGE_SIZE
* @pages: number of pages to add
* @memory_type: type of memory added
* @overlap_only_ram: region may only overlap RAM
* Return: status code
*/
static efi_status_t efi_add_memory_map_pg(u64 start, u64 pages,
int memory_type,
bool overlap_only_ram)
{
struct list_head *lhandle;
struct efi_mem_list *newlist;
bool carve_again;
uint64_t carved_pages = 0;
struct efi_event *evt;
EFI_PRINT("%s: 0x%llx 0x%llx %d %s\n", __func__,
start, pages, memory_type, overlap_only_ram ? "yes" : "no");
if (memory_type >= EFI_MAX_MEMORY_TYPE)
return EFI_INVALID_PARAMETER;
if (!pages)
return EFI_SUCCESS;
++efi_memory_map_key;
newlist = calloc(1, sizeof(*newlist));
newlist->desc.type = memory_type;
newlist->desc.physical_start = start;
newlist->desc.virtual_start = start;
newlist->desc.num_pages = pages;
switch (memory_type) {
case EFI_RUNTIME_SERVICES_CODE:
case EFI_RUNTIME_SERVICES_DATA:
newlist->desc.attribute = EFI_MEMORY_WB | EFI_MEMORY_RUNTIME;
break;
case EFI_MMAP_IO:
newlist->desc.attribute = EFI_MEMORY_RUNTIME;
break;
default:
newlist->desc.attribute = EFI_MEMORY_WB;
break;
}
/* Add our new map */
do {
carve_again = false;
list_for_each(lhandle, &efi_mem) {
struct efi_mem_list *lmem;
s64 r;
lmem = list_entry(lhandle, struct efi_mem_list, link);
r = efi_mem_carve_out(lmem, &newlist->desc,
overlap_only_ram);
switch (r) {
case EFI_CARVE_OVERLAPS_NONRAM:
/*
* The user requested to only have RAM overlaps,
* but we hit a non-RAM region. Error out.
*/
return EFI_NO_MAPPING;
case EFI_CARVE_NO_OVERLAP:
/* Just ignore this list entry */
break;
case EFI_CARVE_LOOP_AGAIN:
/*
* We split an entry, but need to loop through
* the list again to actually carve it.
*/
carve_again = true;
break;
default:
/* We carved a number of pages */
carved_pages += r;
carve_again = true;
break;
}
if (carve_again) {
/* The list changed, we need to start over */
break;
}
}
} while (carve_again);
if (overlap_only_ram && (carved_pages != pages)) {
/*
* The payload wanted to have RAM overlaps, but we overlapped
* with an unallocated region. Error out.
*/
return EFI_NO_MAPPING;
}
/* Add our new map */
list_add_tail(&newlist->link, &efi_mem);
/* And make sure memory is listed in descending order */
efi_mem_sort();
/* Notify that the memory map was changed */
list_for_each_entry(evt, &efi_events, link) {
if (evt->group &&
!guidcmp(evt->group,
&efi_guid_event_group_memory_map_change)) {
efi_signal_event(evt);
break;
}
}
return EFI_SUCCESS;
}
/**
* efi_add_memory_map() - add memory area to the memory map
*
* @start: start address of the memory area
* @size: length in bytes of the memory area
* @memory_type: type of memory added
*
* Return: status code
*
* This function automatically aligns the start and size of the memory area
* to EFI_PAGE_SIZE.
*/
efi_status_t efi_add_memory_map(u64 start, u64 size, int memory_type)
{
u64 pages;
pages = efi_size_in_pages(size + (start & EFI_PAGE_MASK));
start &= ~EFI_PAGE_MASK;
return efi_add_memory_map_pg(start, pages, memory_type, false);
}
/**
* efi_check_allocated() - validate address to be freed
*
* Check that the address is within allocated memory:
*
* * The address must be in a range of the memory map.
* * The address may not point to EFI_CONVENTIONAL_MEMORY.
*
* Page alignment is not checked as this is not a requirement of
* efi_free_pool().
*
* @addr: address of page to be freed
* @must_be_allocated: return success if the page is allocated
* Return: status code
*/
static efi_status_t efi_check_allocated(u64 addr, bool must_be_allocated)
{
struct efi_mem_list *item;
list_for_each_entry(item, &efi_mem, link) {
u64 start = item->desc.physical_start;
u64 end = start + (item->desc.num_pages << EFI_PAGE_SHIFT);
if (addr >= start && addr < end) {
if (must_be_allocated ^
(item->desc.type == EFI_CONVENTIONAL_MEMORY))
return EFI_SUCCESS;
else
return EFI_NOT_FOUND;
}
}
return EFI_NOT_FOUND;
}
static uint64_t efi_find_free_memory(uint64_t len, uint64_t max_addr)
{
struct list_head *lhandle;
/*
* Prealign input max address, so we simplify our matching
* logic below and can just reuse it as return pointer.
*/
max_addr &= ~EFI_PAGE_MASK;
list_for_each(lhandle, &efi_mem) {
struct efi_mem_list *lmem = list_entry(lhandle,
struct efi_mem_list, link);
struct efi_mem_desc *desc = &lmem->desc;
uint64_t desc_len = desc->num_pages << EFI_PAGE_SHIFT;
uint64_t desc_end = desc->physical_start + desc_len;
uint64_t curmax = min(max_addr, desc_end);
uint64_t ret = curmax - len;
/* We only take memory from free RAM */
if (desc->type != EFI_CONVENTIONAL_MEMORY)
continue;
/* Out of bounds for max_addr */
if ((ret + len) > max_addr)
continue;
/* Out of bounds for upper map limit */
if ((ret + len) > desc_end)
continue;
/* Out of bounds for lower map limit */
if (ret < desc->physical_start)
continue;
/* Return the highest address in this map within bounds */
return ret;
}
return 0;
}
/*
* Allocate memory pages.
*
* @type type of allocation to be performed
* @memory_type usage type of the allocated memory
* @pages number of pages to be allocated
* @memory allocated memory
* @return status code
*/
efi_status_t efi_allocate_pages(int type, int memory_type,
efi_uintn_t pages, uint64_t *memory)
{
u64 len = pages << EFI_PAGE_SHIFT;
efi_status_t ret;
uint64_t addr;
/* Check import parameters */
if (memory_type >= EFI_PERSISTENT_MEMORY_TYPE &&
memory_type <= 0x6FFFFFFF)
return EFI_INVALID_PARAMETER;
if (!memory)
return EFI_INVALID_PARAMETER;
switch (type) {
case EFI_ALLOCATE_ANY_PAGES:
/* Any page */
addr = efi_find_free_memory(len, -1ULL);
if (!addr)
return EFI_OUT_OF_RESOURCES;
break;
case EFI_ALLOCATE_MAX_ADDRESS:
/* Max address */
addr = efi_find_free_memory(len, *memory);
if (!addr)
return EFI_OUT_OF_RESOURCES;
break;
case EFI_ALLOCATE_ADDRESS:
/* Exact address, reserve it. The addr is already in *memory. */
ret = efi_check_allocated(*memory, false);
if (ret != EFI_SUCCESS)
return EFI_NOT_FOUND;
addr = *memory;
break;
default:
/* UEFI doesn't specify other allocation types */
return EFI_INVALID_PARAMETER;
}
/* Reserve that map in our memory maps */
ret = efi_add_memory_map_pg(addr, pages, memory_type, true);
if (ret != EFI_SUCCESS)
/* Map would overlap, bail out */
return EFI_OUT_OF_RESOURCES;
*memory = addr;
return EFI_SUCCESS;
}
void *efi_alloc(uint64_t len, int memory_type)
{
uint64_t ret = 0;
uint64_t pages = efi_size_in_pages(len);
efi_status_t r;
r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, memory_type, pages,
&ret);
if (r == EFI_SUCCESS)
return (void*)(uintptr_t)ret;
return NULL;
}
/**
* efi_free_pages() - free memory pages
*
* @memory: start of the memory area to be freed
* @pages: number of pages to be freed
* Return: status code
*/
efi_status_t efi_free_pages(uint64_t memory, efi_uintn_t pages)
{
efi_status_t ret;
ret = efi_check_allocated(memory, true);
if (ret != EFI_SUCCESS)
return ret;
/* Sanity check */
if (!memory || (memory & EFI_PAGE_MASK) || !pages) {
printf("%s: illegal free 0x%llx, 0x%zx\n", __func__,
memory, pages);
return EFI_INVALID_PARAMETER;
}
ret = efi_add_memory_map_pg(memory, pages, EFI_CONVENTIONAL_MEMORY,
false);
/* Merging of adjacent free regions is missing */
if (ret != EFI_SUCCESS)
return EFI_NOT_FOUND;
return ret;
}
/**
* efi_allocate_pool - allocate memory from pool
*
* @pool_type: type of the pool from which memory is to be allocated
* @size: number of bytes to be allocated
* @buffer: allocated memory
* Return: status code
*/
efi_status_t efi_allocate_pool(int pool_type, efi_uintn_t size, void **buffer)
{
efi_status_t r;
u64 addr;
struct efi_pool_allocation *alloc;
u64 num_pages = efi_size_in_pages(size +
sizeof(struct efi_pool_allocation));
if (!buffer)
return EFI_INVALID_PARAMETER;
if (size == 0) {
*buffer = NULL;
return EFI_SUCCESS;
}
r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, pool_type, num_pages,
&addr);
if (r == EFI_SUCCESS) {
alloc = (struct efi_pool_allocation *)(uintptr_t)addr;
alloc->num_pages = num_pages;
alloc->checksum = checksum(alloc);
*buffer = alloc->data;
}
return r;
}
/**
* efi_free_pool() - free memory from pool
*
* @buffer: start of memory to be freed
* Return: status code
*/
efi_status_t efi_free_pool(void *buffer)
{
efi_status_t ret;
struct efi_pool_allocation *alloc;
if (!buffer)
return EFI_INVALID_PARAMETER;
ret = efi_check_allocated((uintptr_t)buffer, true);
if (ret != EFI_SUCCESS)
return ret;
alloc = container_of(buffer, struct efi_pool_allocation, data);
/* Check that this memory was allocated by efi_allocate_pool() */
if (((uintptr_t)alloc & EFI_PAGE_MASK) ||
alloc->checksum != checksum(alloc)) {
printf("%s: illegal free 0x%p\n", __func__, buffer);
return EFI_INVALID_PARAMETER;
}
/* Avoid double free */
alloc->checksum = 0;
ret = efi_free_pages((uintptr_t)alloc, alloc->num_pages);
return ret;
}
/*
* Get map describing memory usage.
*
* @memory_map_size on entry the size, in bytes, of the memory map buffer,
* on exit the size of the copied memory map
* @memory_map buffer to which the memory map is written
* @map_key key for the memory map
* @descriptor_size size of an individual memory descriptor
* @descriptor_version version number of the memory descriptor structure
* @return status code
*/
efi_status_t efi_get_memory_map(efi_uintn_t *memory_map_size,
struct efi_mem_desc *memory_map,
efi_uintn_t *map_key,
efi_uintn_t *descriptor_size,
uint32_t *descriptor_version)
{
efi_uintn_t map_size = 0;
int map_entries = 0;
struct list_head *lhandle;
efi_uintn_t provided_map_size;
if (!memory_map_size)
return EFI_INVALID_PARAMETER;
provided_map_size = *memory_map_size;
list_for_each(lhandle, &efi_mem)
map_entries++;
map_size = map_entries * sizeof(struct efi_mem_desc);
*memory_map_size = map_size;
if (descriptor_size)
*descriptor_size = sizeof(struct efi_mem_desc);
if (descriptor_version)
*descriptor_version = EFI_MEMORY_DESCRIPTOR_VERSION;
if (provided_map_size < map_size)
return EFI_BUFFER_TOO_SMALL;
if (!memory_map)
return EFI_INVALID_PARAMETER;
/* Copy list into array */
/* Return the list in ascending order */
memory_map = &memory_map[map_entries - 1];
list_for_each(lhandle, &efi_mem) {
struct efi_mem_list *lmem;
lmem = list_entry(lhandle, struct efi_mem_list, link);
*memory_map = lmem->desc;
memory_map--;
}
if (map_key)
*map_key = efi_memory_map_key;
return EFI_SUCCESS;
}
/**
* efi_add_conventional_memory_map() - add a RAM memory area to the map
*
* @ram_start: start address of a RAM memory area
* @ram_end: end address of a RAM memory area
* @ram_top: max address to be used as conventional memory
* Return: status code
*/
efi_status_t efi_add_conventional_memory_map(u64 ram_start, u64 ram_end,
u64 ram_top)
{
u64 pages;
/* Remove partial pages */
ram_end &= ~EFI_PAGE_MASK;
ram_start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK;
if (ram_end <= ram_start) {
/* Invalid mapping */
return EFI_INVALID_PARAMETER;
}
pages = (ram_end - ram_start) >> EFI_PAGE_SHIFT;
efi_add_memory_map_pg(ram_start, pages,
EFI_CONVENTIONAL_MEMORY, false);
/*
* Boards may indicate to the U-Boot memory core that they
* can not support memory above ram_top. Let's honor this
* in the efi_loader subsystem too by declaring any memory
* above ram_top as "already occupied by firmware".
*/
if (ram_top < ram_start) {
/* ram_top is before this region, reserve all */
efi_add_memory_map_pg(ram_start, pages,
EFI_BOOT_SERVICES_DATA, true);
} else if ((ram_top >= ram_start) && (ram_top < ram_end)) {
/* ram_top is inside this region, reserve parts */
pages = (ram_end - ram_top) >> EFI_PAGE_SHIFT;
efi_add_memory_map_pg(ram_top, pages,
EFI_BOOT_SERVICES_DATA, true);
}
return EFI_SUCCESS;
}
__weak void efi_add_known_memory(void)
{
u64 ram_top = board_get_usable_ram_top(0) & ~EFI_PAGE_MASK;
int i;
/*
* ram_top is just outside mapped memory. So use an offset of one for
* mapping the sandbox address.
*/
ram_top = (uintptr_t)map_sysmem(ram_top - 1, 0) + 1;
/* Fix for 32bit targets with ram_top at 4G */
if (!ram_top)
ram_top = 0x100000000ULL;
/* Add RAM */
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
u64 ram_end, ram_start;
ram_start = (uintptr_t)map_sysmem(gd->bd->bi_dram[i].start, 0);
ram_end = ram_start + gd->bd->bi_dram[i].size;
efi_add_conventional_memory_map(ram_start, ram_end, ram_top);
}
}
/* Add memory regions for U-Boot's memory and for the runtime services code */
static void add_u_boot_and_runtime(void)
{
unsigned long runtime_start, runtime_end, runtime_pages;
unsigned long runtime_mask = EFI_PAGE_MASK;
unsigned long uboot_start, uboot_pages;
unsigned long uboot_stack_size = CONFIG_STACK_SIZE;
/* Add U-Boot */
uboot_start = ((uintptr_t)map_sysmem(gd->start_addr_sp, 0) -
uboot_stack_size) & ~EFI_PAGE_MASK;
uboot_pages = ((uintptr_t)map_sysmem(gd->ram_top - 1, 0) -
uboot_start + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
efi_add_memory_map_pg(uboot_start, uboot_pages, EFI_LOADER_DATA,
false);
#if defined(__aarch64__)
/*
* Runtime Services must be 64KiB aligned according to the
* "AArch64 Platforms" section in the UEFI spec (2.7+).
*/
runtime_mask = SZ_64K - 1;
#endif
/*
* Add Runtime Services. We mark surrounding boottime code as runtime as
* well to fulfill the runtime alignment constraints but avoid padding.
*/
runtime_start = (ulong)&__efi_runtime_start & ~runtime_mask;
runtime_end = (ulong)&__efi_runtime_stop;
runtime_end = (runtime_end + runtime_mask) & ~runtime_mask;
runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT;
efi_add_memory_map_pg(runtime_start, runtime_pages,
EFI_RUNTIME_SERVICES_CODE, false);
}
int efi_memory_init(void)
{
efi_add_known_memory();
add_u_boot_and_runtime();
#ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
/* Request a 32bit 64MB bounce buffer region */
uint64_t efi_bounce_buffer_addr = 0xffffffff;
if (efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, EFI_LOADER_DATA,
(64 * 1024 * 1024) >> EFI_PAGE_SHIFT,
&efi_bounce_buffer_addr) != EFI_SUCCESS)
return -1;
efi_bounce_buffer = (void*)(uintptr_t)efi_bounce_buffer_addr;
#endif
return 0;
}