[grub2.git] / grub-core / kern / efi / mm.c

/* mm.c - generic EFI memory management */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2006,2007,2008,2009  Free Software Foundation, Inc.
 *
 *  GRUB is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/efi/api.h>
#include <grub/efi/efi.h>
#include <grub/cpu/efi/memory.h>

#if defined (__i386__) || defined (__x86_64__)
#include <grub/pci.h>
#endif

#define NEXT_MEMORY_DESCRIPTOR(desc, size)      \
  ((grub_efi_memory_descriptor_t *) ((char *) (desc) + (size)))

#define BYTES_TO_PAGES(bytes)   (((bytes) + 0xfff) >> 12)
#define BYTES_TO_PAGES_DOWN(bytes)      ((bytes) >> 12)
#define PAGES_TO_BYTES(pages)   ((pages) << 12)

/* The size of a memory map obtained from the firmware. This must be
   a multiplier of 4KB.  */
#define MEMORY_MAP_SIZE 0x3000

/* The minimum and maximum heap size for GRUB itself.  */
#define MIN_HEAP_SIZE   0x100000
#define MAX_HEAP_SIZE   (1600 * 0x100000)

static void *finish_mmap_buf = 0;
static grub_efi_uintn_t finish_mmap_size = 0;
static grub_efi_uintn_t finish_key = 0;
static grub_efi_uintn_t finish_desc_size;
static grub_efi_uint32_t finish_desc_version;
int grub_efi_is_finished = 0;

/* Allocate pages below a specified address */
void *
grub_efi_allocate_pages_max (grub_efi_physical_address_t max,
                             grub_efi_uintn_t pages)
{
  grub_efi_status_t status;
  grub_efi_boot_services_t *b;
  grub_efi_physical_address_t address = max;

  if (max > 0xffffffff)
    return 0;

  b = grub_efi_system_table->boot_services;
  status = efi_call_4 (b->allocate_pages, GRUB_EFI_ALLOCATE_MAX_ADDRESS, GRUB_EFI_LOADER_DATA, pages, &address);

  if (status != GRUB_EFI_SUCCESS)
    return 0;

  if (address == 0)
    {
      /* Uggh, the address 0 was allocated... This is too annoying,
         so reallocate another one.  */
      address = max;
      status = efi_call_4 (b->allocate_pages, GRUB_EFI_ALLOCATE_MAX_ADDRESS, GRUB_EFI_LOADER_DATA, pages, &address);
      grub_efi_free_pages (0, pages);
      if (status != GRUB_EFI_SUCCESS)
        return 0;
    }

  return (void *) ((grub_addr_t) address);
}

/* Allocate pages. Return the pointer to the first of allocated pages.  */
void *
grub_efi_allocate_pages_real (grub_efi_physical_address_t address,
                              grub_efi_uintn_t pages,
                              grub_efi_allocate_type_t alloctype,
                              grub_efi_memory_type_t memtype)
{
  grub_efi_status_t status;
  grub_efi_boot_services_t *b;

  /* Limit the memory access to less than 4GB for 32-bit platforms.  */
  if (address > GRUB_EFI_MAX_USABLE_ADDRESS)
    return 0;

  b = grub_efi_system_table->boot_services;
  status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &address);
  if (status != GRUB_EFI_SUCCESS)
    return 0;

  if (address == 0)
    {
      /* Uggh, the address 0 was allocated... This is too annoying,
         so reallocate another one.  */
      address = GRUB_EFI_MAX_USABLE_ADDRESS;
      status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &address);
      grub_efi_free_pages (0, pages);
      if (status != GRUB_EFI_SUCCESS)
        return 0;
    }

  return (void *) ((grub_addr_t) address);
}

void *
grub_efi_allocate_any_pages (grub_efi_uintn_t pages)
{
  return grub_efi_allocate_pages_real (GRUB_EFI_MAX_USABLE_ADDRESS,
                                       pages, GRUB_EFI_ALLOCATE_MAX_ADDRESS,
                                       GRUB_EFI_LOADER_DATA);
}

void *
grub_efi_allocate_fixed (grub_efi_physical_address_t address,
                         grub_efi_uintn_t pages)
{
  return grub_efi_allocate_pages_real (address, pages,
                                       GRUB_EFI_ALLOCATE_ADDRESS,
                                       GRUB_EFI_LOADER_DATA);
}

/* Free pages starting from ADDRESS.  */
void
grub_efi_free_pages (grub_efi_physical_address_t address,
                     grub_efi_uintn_t pages)
{
  grub_efi_boot_services_t *b;

  b = grub_efi_system_table->boot_services;
  efi_call_2 (b->free_pages, address, pages);
}

#if defined (__i386__) || defined (__x86_64__)

/* Helper for stop_broadcom.  */
static int
find_card (grub_pci_device_t dev, grub_pci_id_t pciid,
           void *data __attribute__ ((unused)))
{
  grub_pci_address_t addr;
  grub_uint8_t cap;
  grub_uint16_t pm_state;

  if ((pciid & 0xffff) != GRUB_PCI_VENDOR_BROADCOM)
    return 0;

  addr = grub_pci_make_address (dev, GRUB_PCI_REG_CLASS);
  if (grub_pci_read (addr) >> 24 != GRUB_PCI_CLASS_NETWORK)
    return 0;
  cap = grub_pci_find_capability (dev, GRUB_PCI_CAP_POWER_MANAGEMENT);
  if (!cap)
    return 0;
  addr = grub_pci_make_address (dev, cap + 4);
  pm_state = grub_pci_read_word (addr);
  pm_state = pm_state | 0x03;
  grub_pci_write_word (addr, pm_state);
  grub_pci_read_word (addr);
  return 0;
}

static void
stop_broadcom (void)
{
  grub_pci_iterate (find_card, NULL);
}

#endif

grub_err_t
grub_efi_finish_boot_services (grub_efi_uintn_t *outbuf_size, void *outbuf,
                               grub_efi_uintn_t *map_key,
                               grub_efi_uintn_t *efi_desc_size,
                               grub_efi_uint32_t *efi_desc_version)
{
  grub_efi_boot_services_t *b;
  grub_efi_status_t status;

#if defined (__i386__) || defined (__x86_64__)
  const grub_uint16_t apple[] = { 'A', 'p', 'p', 'l', 'e' };
  int is_apple;

  is_apple = (grub_memcmp (grub_efi_system_table->firmware_vendor,
                           apple, sizeof (apple)) == 0);
#endif

  while (1)
    {
      if (grub_efi_get_memory_map (&finish_mmap_size, finish_mmap_buf, &finish_key,
                                   &finish_desc_size, &finish_desc_version) < 0)
        return grub_error (GRUB_ERR_IO, "couldn't retrieve memory map");

      if (outbuf && *outbuf_size < finish_mmap_size)
        return grub_error (GRUB_ERR_IO, "memory map buffer is too small");

      finish_mmap_buf = grub_malloc (finish_mmap_size);
      if (!finish_mmap_buf)
        return grub_errno;

      if (grub_efi_get_memory_map (&finish_mmap_size, finish_mmap_buf, &finish_key,
                                   &finish_desc_size, &finish_desc_version) <= 0)
        {
          grub_free (finish_mmap_buf);
          return grub_error (GRUB_ERR_IO, "couldn't retrieve memory map");
        }

      b = grub_efi_system_table->boot_services;
      status = efi_call_2 (b->exit_boot_services, grub_efi_image_handle,
                           finish_key);
      if (status == GRUB_EFI_SUCCESS)
        break;

      if (status != GRUB_EFI_INVALID_PARAMETER)
        {
          grub_free (finish_mmap_buf);
          return grub_error (GRUB_ERR_IO, "couldn't terminate EFI services");
        }

      grub_free (finish_mmap_buf);
      grub_printf ("Trying to terminate EFI services again\n");
    }
  grub_efi_is_finished = 1;
  if (outbuf_size)
    *outbuf_size = finish_mmap_size;
  if (outbuf)
    grub_memcpy (outbuf, finish_mmap_buf, finish_mmap_size);
  if (map_key)
    *map_key = finish_key;
  if (efi_desc_size)
    *efi_desc_size = finish_desc_size;
  if (efi_desc_version)
    *efi_desc_version = finish_desc_version;

#if defined (__i386__) || defined (__x86_64__)
  if (is_apple)
    stop_broadcom ();
#endif

  return GRUB_ERR_NONE;
}

/*
 * To obtain the UEFI memory map, we must pass a buffer of sufficient size
 * to hold the entire map. This function returns a sane start value for
 * buffer size.
 */
grub_efi_uintn_t
grub_efi_find_mmap_size (void)
{
  grub_efi_uintn_t mmap_size = 0;
  grub_efi_uintn_t desc_size;

  if (grub_efi_get_memory_map (&mmap_size, NULL, NULL, &desc_size, 0) < 0)
    {
      grub_error (GRUB_ERR_IO, "cannot get EFI memory map size");
      return 0;
    }

  /*
   * Add an extra page, since UEFI can alter the memory map itself on
   * callbacks or explicit calls, including console output.
   */
  return ALIGN_UP (mmap_size + GRUB_EFI_PAGE_SIZE, GRUB_EFI_PAGE_SIZE);
}

/* Get the memory map as defined in the EFI spec. Return 1 if successful,
   return 0 if partial, or return -1 if an error occurs.  */
int
grub_efi_get_memory_map (grub_efi_uintn_t *memory_map_size,
                         grub_efi_memory_descriptor_t *memory_map,
                         grub_efi_uintn_t *map_key,
                         grub_efi_uintn_t *descriptor_size,
                         grub_efi_uint32_t *descriptor_version)
{
  grub_efi_status_t status;
  grub_efi_boot_services_t *b;
  grub_efi_uintn_t key;
  grub_efi_uint32_t version;
  grub_efi_uintn_t size;

  if (grub_efi_is_finished)
    {
      int ret = 1;
      if (*memory_map_size < finish_mmap_size)
        {
          grub_memcpy (memory_map, finish_mmap_buf, *memory_map_size);
          ret = 0;
        }
      else
        {
          grub_memcpy (memory_map, finish_mmap_buf, finish_mmap_size);
          ret = 1;
        }
      *memory_map_size = finish_mmap_size;
      if (map_key)
        *map_key = finish_key;
      if (descriptor_size)
        *descriptor_size = finish_desc_size;
      if (descriptor_version)
        *descriptor_version = finish_desc_version;
      return ret;
    }

  /* Allow some parameters to be missing.  */
  if (! map_key)
    map_key = &key;
  if (! descriptor_version)
    descriptor_version = &version;
  if (! descriptor_size)
    descriptor_size = &size;

  b = grub_efi_system_table->boot_services;
  status = efi_call_5 (b->get_memory_map, memory_map_size, memory_map, map_key,
                              descriptor_size, descriptor_version);
  if (*descriptor_size == 0)
    *descriptor_size = sizeof (grub_efi_memory_descriptor_t);
  if (status == GRUB_EFI_SUCCESS)
    return 1;
  else if (status == GRUB_EFI_BUFFER_TOO_SMALL)
    return 0;
  else
    return -1;
}

/* Sort the memory map in place.  */
static void
sort_memory_map (grub_efi_memory_descriptor_t *memory_map,
                 grub_efi_uintn_t desc_size,
                 grub_efi_memory_descriptor_t *memory_map_end)
{
  grub_efi_memory_descriptor_t *d1;
  grub_efi_memory_descriptor_t *d2;

  for (d1 = memory_map;
       d1 < memory_map_end;
       d1 = NEXT_MEMORY_DESCRIPTOR (d1, desc_size))
    {
      grub_efi_memory_descriptor_t *max_desc = d1;

      for (d2 = NEXT_MEMORY_DESCRIPTOR (d1, desc_size);
           d2 < memory_map_end;
           d2 = NEXT_MEMORY_DESCRIPTOR (d2, desc_size))
        {
          if (max_desc->num_pages < d2->num_pages)
            max_desc = d2;
        }

      if (max_desc != d1)
        {
          grub_efi_memory_descriptor_t tmp;

          tmp = *d1;
          *d1 = *max_desc;
          *max_desc = tmp;
        }
    }
}

/* Filter the descriptors. GRUB needs only available memory.  */
static grub_efi_memory_descriptor_t *
filter_memory_map (grub_efi_memory_descriptor_t *memory_map,
                   grub_efi_memory_descriptor_t *filtered_memory_map,
                   grub_efi_uintn_t desc_size,
                   grub_efi_memory_descriptor_t *memory_map_end)
{
  grub_efi_memory_descriptor_t *desc;
  grub_efi_memory_descriptor_t *filtered_desc;

  for (desc = memory_map, filtered_desc = filtered_memory_map;
       desc < memory_map_end;
       desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size))
    {
      if (desc->type == GRUB_EFI_CONVENTIONAL_MEMORY
#if 1
          && desc->physical_start <= GRUB_EFI_MAX_USABLE_ADDRESS
#endif
          && desc->physical_start + PAGES_TO_BYTES (desc->num_pages) > 0x100000
          && desc->num_pages != 0)
        {
          grub_memcpy (filtered_desc, desc, desc_size);

          /* Avoid less than 1MB, because some loaders seem to be confused.  */
          if (desc->physical_start < 0x100000)
            {
              desc->num_pages -= BYTES_TO_PAGES (0x100000
                                                 - desc->physical_start);
              desc->physical_start = 0x100000;
            }

#if 1
          if (BYTES_TO_PAGES (filtered_desc->physical_start)
              + filtered_desc->num_pages
              > BYTES_TO_PAGES_DOWN (GRUB_EFI_MAX_USABLE_ADDRESS))
            filtered_desc->num_pages
              = (BYTES_TO_PAGES_DOWN (GRUB_EFI_MAX_USABLE_ADDRESS)
                 - BYTES_TO_PAGES (filtered_desc->physical_start));
#endif

          if (filtered_desc->num_pages == 0)
            continue;

          filtered_desc = NEXT_MEMORY_DESCRIPTOR (filtered_desc, desc_size);
        }
    }

  return filtered_desc;
}

/* Return the total number of pages.  */
static grub_efi_uint64_t
get_total_pages (grub_efi_memory_descriptor_t *memory_map,
                 grub_efi_uintn_t desc_size,
                 grub_efi_memory_descriptor_t *memory_map_end)
{
  grub_efi_memory_descriptor_t *desc;
  grub_efi_uint64_t total = 0;

  for (desc = memory_map;
       desc < memory_map_end;
       desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size))
    total += desc->num_pages;

  return total;
}

/* Add memory regions.  */
static void
add_memory_regions (grub_efi_memory_descriptor_t *memory_map,
                    grub_efi_uintn_t desc_size,
                    grub_efi_memory_descriptor_t *memory_map_end,
                    grub_efi_uint64_t required_pages)
{
  grub_efi_memory_descriptor_t *desc;

  for (desc = memory_map;
       desc < memory_map_end;
       desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size))
    {
      grub_efi_uint64_t pages;
      grub_efi_physical_address_t start;
      void *addr;

      start = desc->physical_start;
      pages = desc->num_pages;
      if (pages > required_pages)
        {
          start += PAGES_TO_BYTES (pages - required_pages);
          pages = required_pages;
        }

      addr = grub_efi_allocate_pages_real (start, pages,
                                           GRUB_EFI_ALLOCATE_ADDRESS,
                                           GRUB_EFI_LOADER_CODE);      
      if (! addr)
        grub_fatal ("cannot allocate conventional memory %p with %u pages",
                    (void *) ((grub_addr_t) start),
                    (unsigned) pages);

      grub_mm_init_region (addr, PAGES_TO_BYTES (pages));

      required_pages -= pages;
      if (required_pages == 0)
        break;
    }

  if (required_pages > 0)
    grub_fatal ("too little memory");
}

#if 0
/* Print the memory map.  */
static void
print_memory_map (grub_efi_memory_descriptor_t *memory_map,
                  grub_efi_uintn_t desc_size,
                  grub_efi_memory_descriptor_t *memory_map_end)
{
  grub_efi_memory_descriptor_t *desc;
  int i;

  for (desc = memory_map, i = 0;
       desc < memory_map_end;
       desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size), i++)
    {
      grub_printf ("MD: t=%x, p=%llx, v=%llx, n=%llx, a=%llx\n",
                   desc->type, desc->physical_start, desc->virtual_start,
                   desc->num_pages, desc->attribute);
    }
}
#endif

void
grub_efi_mm_init (void)
{
  grub_efi_memory_descriptor_t *memory_map;
  grub_efi_memory_descriptor_t *memory_map_end;
  grub_efi_memory_descriptor_t *filtered_memory_map;
  grub_efi_memory_descriptor_t *filtered_memory_map_end;
  grub_efi_uintn_t map_size;
  grub_efi_uintn_t desc_size;
  grub_efi_uint64_t total_pages;
  grub_efi_uint64_t required_pages;
  int mm_status;

  /* Prepare a memory region to store two memory maps.  */
  memory_map = grub_efi_allocate_any_pages (2 * BYTES_TO_PAGES (MEMORY_MAP_SIZE));
  if (! memory_map)
    grub_fatal ("cannot allocate memory");

  /* Obtain descriptors for available memory.  */
  map_size = MEMORY_MAP_SIZE;

  mm_status = grub_efi_get_memory_map (&map_size, memory_map, 0, &desc_size, 0);

  if (mm_status == 0)
    {
      grub_efi_free_pages
        ((grub_efi_physical_address_t) ((grub_addr_t) memory_map),
         2 * BYTES_TO_PAGES (MEMORY_MAP_SIZE));

      /* Freeing/allocating operations may increase memory map size.  */
      map_size += desc_size * 32;

      memory_map = grub_efi_allocate_any_pages (2 * BYTES_TO_PAGES (map_size));
      if (! memory_map)
        grub_fatal ("cannot allocate memory");

      mm_status = grub_efi_get_memory_map (&map_size, memory_map, 0,
                                           &desc_size, 0);
    }

  if (mm_status < 0)
    grub_fatal ("cannot get memory map");

  memory_map_end = NEXT_MEMORY_DESCRIPTOR (memory_map, map_size);

  filtered_memory_map = memory_map_end;

  filtered_memory_map_end = filter_memory_map (memory_map, filtered_memory_map,
                                               desc_size, memory_map_end);

  /* By default, request a quarter of the available memory.  */
  total_pages = get_total_pages (filtered_memory_map, desc_size,
                                 filtered_memory_map_end);
  required_pages = (total_pages >> 2);
  if (required_pages < BYTES_TO_PAGES (MIN_HEAP_SIZE))
    required_pages = BYTES_TO_PAGES (MIN_HEAP_SIZE);
  else if (required_pages > BYTES_TO_PAGES (MAX_HEAP_SIZE))
    required_pages = BYTES_TO_PAGES (MAX_HEAP_SIZE);

  /* Sort the filtered descriptors, so that GRUB can allocate pages
     from smaller regions.  */
  sort_memory_map (filtered_memory_map, desc_size, filtered_memory_map_end);

  /* Allocate memory regions for GRUB's memory management.  */
  add_memory_regions (filtered_memory_map, desc_size,
                      filtered_memory_map_end, required_pages);

#if 0
  /* For debug.  */
  map_size = MEMORY_MAP_SIZE;

  if (grub_efi_get_memory_map (&map_size, memory_map, 0, &desc_size, 0) < 0)
    grub_fatal ("cannot get memory map");

  grub_printf ("printing memory map\n");
  print_memory_map (memory_map, desc_size,
                    NEXT_MEMORY_DESCRIPTOR (memory_map, map_size));
  grub_fatal ("Debug. ");
#endif

  /* Release the memory maps.  */
  grub_efi_free_pages ((grub_addr_t) memory_map,
                       2 * BYTES_TO_PAGES (MEMORY_MAP_SIZE));
}