blob: 4ef20b49eb5e72e4893fc5eabc969d6941368d35 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Common EFI memory map functions.
*/
#define pr_fmt(fmt) "efi: " fmt
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/efi.h>
#include <linux/io.h>
#include <asm/early_ioremap.h>
#include <asm/efi.h>
#include <linux/memblock.h>
#include <linux/slab.h>
static phys_addr_t __init __efi_memmap_alloc_early(unsigned long size)
{
return memblock_phys_alloc(size, SMP_CACHE_BYTES);
}
static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
{
unsigned int order = get_order(size);
struct page *p = alloc_pages(GFP_KERNEL, order);
if (!p)
return 0;
return PFN_PHYS(page_to_pfn(p));
}
void __init __efi_memmap_free(u64 phys, unsigned long size, unsigned long flags)
{
if (flags & EFI_MEMMAP_MEMBLOCK) {
if (slab_is_available())
memblock_free_late(phys, size);
else
memblock_phys_free(phys, size);
} else if (flags & EFI_MEMMAP_SLAB) {
struct page *p = pfn_to_page(PHYS_PFN(phys));
unsigned int order = get_order(size);
free_pages((unsigned long) page_address(p), order);
}
}
/**
* efi_memmap_alloc - Allocate memory for the EFI memory map
* @num_entries: Number of entries in the allocated map.
* @data: efi memmap installation parameters
*
* Depending on whether mm_init() has already been invoked or not,
* either memblock or "normal" page allocation is used.
*
* Returns zero on success, a negative error code on failure.
*/
int __init efi_memmap_alloc(unsigned int num_entries,
struct efi_memory_map_data *data)
{
/* Expect allocation parameters are zero initialized */
WARN_ON(data->phys_map || data->size);
data->size = num_entries * efi.memmap.desc_size;
data->desc_version = efi.memmap.desc_version;
data->desc_size = efi.memmap.desc_size;
data->flags &= ~(EFI_MEMMAP_SLAB | EFI_MEMMAP_MEMBLOCK);
data->flags |= efi.memmap.flags & EFI_MEMMAP_LATE;
if (slab_is_available()) {
data->flags |= EFI_MEMMAP_SLAB;
data->phys_map = __efi_memmap_alloc_late(data->size);
} else {
data->flags |= EFI_MEMMAP_MEMBLOCK;
data->phys_map = __efi_memmap_alloc_early(data->size);
}
if (!data->phys_map)
return -ENOMEM;
return 0;
}
/**
* efi_memmap_install - Install a new EFI memory map in efi.memmap
* @data: efi memmap installation parameters
*
* Unlike efi_memmap_init_*(), this function does not allow the caller
* to switch from early to late mappings. It simply uses the existing
* mapping function and installs the new memmap.
*
* Returns zero on success, a negative error code on failure.
*/
int __init efi_memmap_install(struct efi_memory_map_data *data)
{
efi_memmap_unmap();
if (efi_enabled(EFI_PARAVIRT))
return 0;
return __efi_memmap_init(data);
}
/**
* efi_memmap_split_count - Count number of additional EFI memmap entries
* @md: EFI memory descriptor to split
* @range: Address range (start, end) to split around
*
* Returns the number of additional EFI memmap entries required to
* accommodate @range.
*/
int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
{
u64 m_start, m_end;
u64 start, end;
int count = 0;
start = md->phys_addr;
end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
/* modifying range */
m_start = range->start;
m_end = range->end;
if (m_start <= start) {
/* split into 2 parts */
if (start < m_end && m_end < end)
count++;
}
if (start < m_start && m_start < end) {
/* split into 3 parts */
if (m_end < end)
count += 2;
/* split into 2 parts */
if (end <= m_end)
count++;
}
return count;
}
/**
* efi_memmap_insert - Insert a memory region in an EFI memmap
* @old_memmap: The existing EFI memory map structure
* @buf: Address of buffer to store new map
* @mem: Memory map entry to insert
*
* It is suggested that you call efi_memmap_split_count() first
* to see how large @buf needs to be.
*/
void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf,
struct efi_mem_range *mem)
{
u64 m_start, m_end, m_attr;
efi_memory_desc_t *md;
u64 start, end;
void *old, *new;
/* modifying range */
m_start = mem->range.start;
m_end = mem->range.end;
m_attr = mem->attribute;
/*
* The EFI memory map deals with regions in EFI_PAGE_SIZE
* units. Ensure that the region described by 'mem' is aligned
* correctly.
*/
if (!IS_ALIGNED(m_start, EFI_PAGE_SIZE) ||
!IS_ALIGNED(m_end + 1, EFI_PAGE_SIZE)) {
WARN_ON(1);
return;
}
for (old = old_memmap->map, new = buf;
old < old_memmap->map_end;
old += old_memmap->desc_size, new += old_memmap->desc_size) {
/* copy original EFI memory descriptor */
memcpy(new, old, old_memmap->desc_size);
md = new;
start = md->phys_addr;
end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
if (m_start <= start && end <= m_end)
md->attribute |= m_attr;
if (m_start <= start &&
(start < m_end && m_end < end)) {
/* first part */
md->attribute |= m_attr;
md->num_pages = (m_end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
/* latter part */
new += old_memmap->desc_size;
memcpy(new, old, old_memmap->desc_size);
md = new;
md->phys_addr = m_end + 1;
md->num_pages = (end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
}
if ((start < m_start && m_start < end) && m_end < end) {
/* first part */
md->num_pages = (m_start - md->phys_addr) >>
EFI_PAGE_SHIFT;
/* middle part */
new += old_memmap->desc_size;
memcpy(new, old, old_memmap->desc_size);
md = new;
md->attribute |= m_attr;
md->phys_addr = m_start;
md->num_pages = (m_end - m_start + 1) >>
EFI_PAGE_SHIFT;
/* last part */
new += old_memmap->desc_size;
memcpy(new, old, old_memmap->desc_size);
md = new;
md->phys_addr = m_end + 1;
md->num_pages = (end - m_end) >>
EFI_PAGE_SHIFT;
}
if ((start < m_start && m_start < end) &&
(end <= m_end)) {
/* first part */
md->num_pages = (m_start - md->phys_addr) >>
EFI_PAGE_SHIFT;
/* latter part */
new += old_memmap->desc_size;
memcpy(new, old, old_memmap->desc_size);
md = new;
md->phys_addr = m_start;
md->num_pages = (end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
md->attribute |= m_attr;
}
}
}