freebsd-skq/stand/efi/loader/copy.c
bcran 8347d20afe Add retry loop around GetMemoryMap call to fix fragmentation bug
The call to BS->AllocatePages can cause the memory map to become framented,
causing BS->GetMemoryMap to return EFI_BUFFER_TOO_SMALL more than once. For
example this can happen on the MinnowBoard Turbot, causing the boot to stop
with an error. Avoid this by calling GetMemoryMap in a loop.

Reviewed by:	imp, tsoome, kevans
Differential Revision:	https://reviews.freebsd.org/D19341
2019-03-06 05:39:40 +00:00

299 lines
7.4 KiB
C

/*-
* Copyright (c) 2013 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Benno Rice under sponsorship from
* the FreeBSD Foundation.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <stand.h>
#include <bootstrap.h>
#include <efi.h>
#include <efilib.h>
#include "loader_efi.h"
#if defined(__i386__) || defined(__amd64__)
#include <machine/cpufunc.h>
#include <machine/specialreg.h>
/*
* The code is excerpted from sys/x86/x86/identcpu.c: identify_cpu(),
* identify_hypervisor(), and dev/hyperv/vmbus/hyperv.c: hyperv_identify().
*/
#define CPUID_LEAF_HV_MAXLEAF 0x40000000
#define CPUID_LEAF_HV_INTERFACE 0x40000001
#define CPUID_LEAF_HV_FEATURES 0x40000003
#define CPUID_LEAF_HV_LIMITS 0x40000005
#define CPUID_HV_IFACE_HYPERV 0x31237648 /* HV#1 */
#define CPUID_HV_MSR_TIME_REFCNT 0x0002 /* MSR_HV_TIME_REF_COUNT */
#define CPUID_HV_MSR_HYPERCALL 0x0020
static int
running_on_hyperv(void)
{
char hv_vendor[16];
uint32_t regs[4];
do_cpuid(1, regs);
if ((regs[2] & CPUID2_HV) == 0)
return (0);
do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs);
if (regs[0] < CPUID_LEAF_HV_LIMITS)
return (0);
((uint32_t *)&hv_vendor)[0] = regs[1];
((uint32_t *)&hv_vendor)[1] = regs[2];
((uint32_t *)&hv_vendor)[2] = regs[3];
hv_vendor[12] = '\0';
if (strcmp(hv_vendor, "Microsoft Hv") != 0)
return (0);
do_cpuid(CPUID_LEAF_HV_INTERFACE, regs);
if (regs[0] != CPUID_HV_IFACE_HYPERV)
return (0);
do_cpuid(CPUID_LEAF_HV_FEATURES, regs);
if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0)
return (0);
if ((regs[0] & CPUID_HV_MSR_TIME_REFCNT) == 0)
return (0);
return (1);
}
#define KERNEL_PHYSICAL_BASE (2*1024*1024)
static void
efi_verify_staging_size(unsigned long *nr_pages)
{
UINTN sz;
EFI_MEMORY_DESCRIPTOR *map = NULL, *p;
EFI_PHYSICAL_ADDRESS start, end;
UINTN key, dsz;
UINT32 dver;
EFI_STATUS status;
int i, ndesc;
unsigned long available_pages = 0;
sz = 0;
for (;;) {
status = BS->GetMemoryMap(&sz, map, &key, &dsz, &dver);
if (!EFI_ERROR(status))
break;
if (status != EFI_BUFFER_TOO_SMALL) {
printf("Can't read memory map: %lu\n",
EFI_ERROR_CODE(status));
goto out;
}
free(map);
/* Allocate 10 descriptors more than the size reported,
* to allow for any fragmentation caused by calling
* malloc */
map = malloc(sz + (10 * dsz));
if (map == NULL) {
printf("Unable to allocate memory\n");
goto out;
}
}
ndesc = sz / dsz;
for (i = 0, p = map; i < ndesc;
i++, p = NextMemoryDescriptor(p, dsz)) {
start = p->PhysicalStart;
end = start + p->NumberOfPages * EFI_PAGE_SIZE;
if (KERNEL_PHYSICAL_BASE < start ||
KERNEL_PHYSICAL_BASE >= end)
continue;
available_pages = p->NumberOfPages -
((KERNEL_PHYSICAL_BASE - start) >> EFI_PAGE_SHIFT);
break;
}
if (available_pages == 0) {
printf("Can't find valid memory map for staging area!\n");
goto out;
}
i++;
p = NextMemoryDescriptor(p, dsz);
for ( ; i < ndesc;
i++, p = NextMemoryDescriptor(p, dsz)) {
if (p->Type != EfiConventionalMemory &&
p->Type != EfiLoaderData)
break;
if (p->PhysicalStart != end)
break;
end = p->PhysicalStart + p->NumberOfPages * EFI_PAGE_SIZE;
available_pages += p->NumberOfPages;
}
if (*nr_pages > available_pages) {
printf("Staging area's size is reduced: %ld -> %ld!\n",
*nr_pages, available_pages);
*nr_pages = available_pages;
}
out:
free(map);
}
#endif /* __i386__ || __amd64__ */
#ifndef EFI_STAGING_SIZE
#define EFI_STAGING_SIZE 64
#endif
EFI_PHYSICAL_ADDRESS staging, staging_end;
int stage_offset_set = 0;
ssize_t stage_offset;
int
efi_copy_init(void)
{
EFI_STATUS status;
unsigned long nr_pages;
nr_pages = EFI_SIZE_TO_PAGES((EFI_STAGING_SIZE) * 1024 * 1024);
#if defined(__i386__) || defined(__amd64__)
/*
* We'll decrease nr_pages, if it's too big. Currently we only
* apply this to FreeBSD VM running on Hyper-V. Why? Please see
* https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211746#c28
*/
if (running_on_hyperv())
efi_verify_staging_size(&nr_pages);
/*
* The staging area must reside in the the first 1GB physical
* memory: see elf64_exec() in
* boot/efi/loader/arch/amd64/elf64_freebsd.c.
*/
staging = 1024*1024*1024;
status = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData,
nr_pages, &staging);
#else
status = BS->AllocatePages(AllocateAnyPages, EfiLoaderData,
nr_pages, &staging);
#endif
if (EFI_ERROR(status)) {
printf("failed to allocate staging area: %lu\n",
EFI_ERROR_CODE(status));
return (status);
}
staging_end = staging + nr_pages * EFI_PAGE_SIZE;
#if defined(__aarch64__) || defined(__arm__)
/*
* Round the kernel load address to a 2MiB value. This is needed
* because the kernel builds a page table based on where it has
* been loaded in physical address space. As the kernel will use
* either a 1MiB or 2MiB page for this we need to make sure it
* is correctly aligned for both cases.
*/
staging = roundup2(staging, 2 * 1024 * 1024);
#endif
return (0);
}
void *
efi_translate(vm_offset_t ptr)
{
return ((void *)(ptr + stage_offset));
}
ssize_t
efi_copyin(const void *src, vm_offset_t dest, const size_t len)
{
if (!stage_offset_set) {
stage_offset = (vm_offset_t)staging - dest;
stage_offset_set = 1;
}
/* XXX: Callers do not check for failure. */
if (dest + stage_offset + len > staging_end) {
errno = ENOMEM;
return (-1);
}
bcopy(src, (void *)(dest + stage_offset), len);
return (len);
}
ssize_t
efi_copyout(const vm_offset_t src, void *dest, const size_t len)
{
/* XXX: Callers do not check for failure. */
if (src + stage_offset + len > staging_end) {
errno = ENOMEM;
return (-1);
}
bcopy((void *)(src + stage_offset), dest, len);
return (len);
}
ssize_t
efi_readin(const int fd, vm_offset_t dest, const size_t len)
{
if (dest + stage_offset + len > staging_end) {
errno = ENOMEM;
return (-1);
}
return (read(fd, (void *)(dest + stage_offset), len));
}
void
efi_copy_finish(void)
{
uint64_t *src, *dst, *last;
src = (uint64_t *)(uintptr_t)staging;
dst = (uint64_t *)(uintptr_t)(staging - stage_offset);
last = (uint64_t *)(uintptr_t)staging_end;
while (src < last)
*dst++ = *src++;
}