qemu-patch-raspberry4/include/exec/ram_addr.h
Peter Maydell f874bf905f exec: Handle multipage ranges in invalidate_and_set_dirty()
The code in invalidate_and_set_dirty() needs to handle addr/length
combinations which cross guest physical page boundaries. This can happen,
for example, when disk I/O reads large blocks into guest RAM which previously
held code that we have cached translations for. Unfortunately we were only
checking the clean/dirty status of the first page in the range, and then
were calling a tb_invalidate function which only handles ranges that don't
cross page boundaries. Fix the function to deal with multipage ranges.

The symptoms of this bug were that guest code would misbehave (eg segfault),
in particular after a guest reboot but potentially any time the guest
reused a page of its physical RAM for new code.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416167061-13203-1-git-send-email-peter.maydell@linaro.org
2014-11-18 10:19:12 +00:00

192 lines
6.8 KiB
C

/*
* Declarations for cpu physical memory functions
*
* Copyright 2011 Red Hat, Inc. and/or its affiliates
*
* Authors:
* Avi Kivity <avi@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*
*/
/*
* This header is for use by exec.c and memory.c ONLY. Do not include it.
* The functions declared here will be removed soon.
*/
#ifndef RAM_ADDR_H
#define RAM_ADDR_H
#ifndef CONFIG_USER_ONLY
#include "hw/xen/xen.h"
ram_addr_t qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
bool share, const char *mem_path,
Error **errp);
ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
MemoryRegion *mr, Error **errp);
ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp);
int qemu_get_ram_fd(ram_addr_t addr);
void *qemu_get_ram_block_host_ptr(ram_addr_t addr);
void *qemu_get_ram_ptr(ram_addr_t addr);
void qemu_ram_free(ram_addr_t addr);
void qemu_ram_free_from_ptr(ram_addr_t addr);
static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
unsigned long end, page, next;
assert(client < DIRTY_MEMORY_NUM);
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
next = find_next_bit(ram_list.dirty_memory[client], end, page);
return next < end;
}
static inline bool cpu_physical_memory_get_clean(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
unsigned long end, page, next;
assert(client < DIRTY_MEMORY_NUM);
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
next = find_next_zero_bit(ram_list.dirty_memory[client], end, page);
return next < end;
}
static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
unsigned client)
{
return cpu_physical_memory_get_dirty(addr, 1, client);
}
static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
{
bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
bool migration =
cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
return !(vga && code && migration);
}
static inline bool cpu_physical_memory_range_includes_clean(ram_addr_t start,
ram_addr_t length)
{
bool vga = cpu_physical_memory_get_clean(start, length, DIRTY_MEMORY_VGA);
bool code = cpu_physical_memory_get_clean(start, length, DIRTY_MEMORY_CODE);
bool migration =
cpu_physical_memory_get_clean(start, length, DIRTY_MEMORY_MIGRATION);
return vga || code || migration;
}
static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
unsigned client)
{
assert(client < DIRTY_MEMORY_NUM);
set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
}
static inline void cpu_physical_memory_set_dirty_range_nocode(ram_addr_t start,
ram_addr_t length)
{
unsigned long end, page;
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
}
static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
ram_addr_t length)
{
unsigned long end, page;
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_CODE], page, end - page);
xen_modified_memory(start, length);
}
#if !defined(_WIN32)
static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
ram_addr_t start,
ram_addr_t pages)
{
unsigned long i, j;
unsigned long page_number, c;
hwaddr addr;
ram_addr_t ram_addr;
unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
unsigned long hpratio = getpagesize() / TARGET_PAGE_SIZE;
unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
/* start address is aligned at the start of a word? */
if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
(hpratio == 1)) {
long k;
long nr = BITS_TO_LONGS(pages);
for (k = 0; k < nr; k++) {
if (bitmap[k]) {
unsigned long temp = leul_to_cpu(bitmap[k]);
ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION][page + k] |= temp;
ram_list.dirty_memory[DIRTY_MEMORY_VGA][page + k] |= temp;
ram_list.dirty_memory[DIRTY_MEMORY_CODE][page + k] |= temp;
}
}
xen_modified_memory(start, pages);
} else {
/*
* bitmap-traveling is faster than memory-traveling (for addr...)
* especially when most of the memory is not dirty.
*/
for (i = 0; i < len; i++) {
if (bitmap[i] != 0) {
c = leul_to_cpu(bitmap[i]);
do {
j = ctzl(c);
c &= ~(1ul << j);
page_number = (i * HOST_LONG_BITS + j) * hpratio;
addr = page_number * TARGET_PAGE_SIZE;
ram_addr = start + addr;
cpu_physical_memory_set_dirty_range(ram_addr,
TARGET_PAGE_SIZE * hpratio);
} while (c != 0);
}
}
}
}
#endif /* not _WIN32 */
static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
ram_addr_t length,
unsigned client)
{
unsigned long end, page;
assert(client < DIRTY_MEMORY_NUM);
end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
page = start >> TARGET_PAGE_BITS;
bitmap_clear(ram_list.dirty_memory[client], page, end - page);
}
void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t length,
unsigned client);
#endif
#endif