qemu/cputlb.c
Richard Henderson 01ecaf438b tcg: Merge GETPC and GETRA
The return address argument to the softmmu template helpers was
confused.  In the legacy case, we wanted to indicate that there
is no return address, and so passed in NULL.  However, we then
immediately subtracted GETPC_ADJ from NULL, resulting in a non-zero
value, indicating the presence of an (invalid) return address.

Push the GETPC_ADJ subtraction down to the only point it's required:
immediately before use within cpu_restore_state_from_tb, after all
NULL pointer checks have been completed.

This makes GETPC and GETRA identical.  Remove GETRA as the lesser
used macro, replacing all uses with GETPC.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00

561 lines
17 KiB
C

/*
* Common CPU TLB handling
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/exec-all.h"
#include "exec/memory.h"
#include "exec/address-spaces.h"
#include "exec/cpu_ldst.h"
#include "exec/cputlb.h"
#include "exec/memory-internal.h"
#include "exec/ram_addr.h"
#include "exec/exec-all.h"
#include "tcg/tcg.h"
#include "qemu/error-report.h"
#include "exec/log.h"
/* DEBUG defines, enable DEBUG_TLB_LOG to log to the CPU_LOG_MMU target */
/* #define DEBUG_TLB */
/* #define DEBUG_TLB_LOG */
#ifdef DEBUG_TLB
# define DEBUG_TLB_GATE 1
# ifdef DEBUG_TLB_LOG
# define DEBUG_TLB_LOG_GATE 1
# else
# define DEBUG_TLB_LOG_GATE 0
# endif
#else
# define DEBUG_TLB_GATE 0
# define DEBUG_TLB_LOG_GATE 0
#endif
#define tlb_debug(fmt, ...) do { \
if (DEBUG_TLB_LOG_GATE) { \
qemu_log_mask(CPU_LOG_MMU, "%s: " fmt, __func__, \
## __VA_ARGS__); \
} else if (DEBUG_TLB_GATE) { \
fprintf(stderr, "%s: " fmt, __func__, ## __VA_ARGS__); \
} \
} while (0)
/* statistics */
int tlb_flush_count;
/* NOTE:
* If flush_global is true (the usual case), flush all tlb entries.
* If flush_global is false, flush (at least) all tlb entries not
* marked global.
*
* Since QEMU doesn't currently implement a global/not-global flag
* for tlb entries, at the moment tlb_flush() will also flush all
* tlb entries in the flush_global == false case. This is OK because
* CPU architectures generally permit an implementation to drop
* entries from the TLB at any time, so flushing more entries than
* required is only an efficiency issue, not a correctness issue.
*/
void tlb_flush(CPUState *cpu, int flush_global)
{
CPUArchState *env = cpu->env_ptr;
tlb_debug("(%d)\n", flush_global);
memset(env->tlb_table, -1, sizeof(env->tlb_table));
memset(env->tlb_v_table, -1, sizeof(env->tlb_v_table));
memset(cpu->tb_jmp_cache, 0, sizeof(cpu->tb_jmp_cache));
env->vtlb_index = 0;
env->tlb_flush_addr = -1;
env->tlb_flush_mask = 0;
tlb_flush_count++;
}
static inline void v_tlb_flush_by_mmuidx(CPUState *cpu, va_list argp)
{
CPUArchState *env = cpu->env_ptr;
tlb_debug("start\n");
for (;;) {
int mmu_idx = va_arg(argp, int);
if (mmu_idx < 0) {
break;
}
tlb_debug("%d\n", mmu_idx);
memset(env->tlb_table[mmu_idx], -1, sizeof(env->tlb_table[0]));
memset(env->tlb_v_table[mmu_idx], -1, sizeof(env->tlb_v_table[0]));
}
memset(cpu->tb_jmp_cache, 0, sizeof(cpu->tb_jmp_cache));
}
void tlb_flush_by_mmuidx(CPUState *cpu, ...)
{
va_list argp;
va_start(argp, cpu);
v_tlb_flush_by_mmuidx(cpu, argp);
va_end(argp);
}
static inline void tlb_flush_entry(CPUTLBEntry *tlb_entry, target_ulong addr)
{
if (addr == (tlb_entry->addr_read &
(TARGET_PAGE_MASK | TLB_INVALID_MASK)) ||
addr == (tlb_entry->addr_write &
(TARGET_PAGE_MASK | TLB_INVALID_MASK)) ||
addr == (tlb_entry->addr_code &
(TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
memset(tlb_entry, -1, sizeof(*tlb_entry));
}
}
void tlb_flush_page(CPUState *cpu, target_ulong addr)
{
CPUArchState *env = cpu->env_ptr;
int i;
int mmu_idx;
tlb_debug("page :" TARGET_FMT_lx "\n", addr);
/* Check if we need to flush due to large pages. */
if ((addr & env->tlb_flush_mask) == env->tlb_flush_addr) {
tlb_debug("forcing full flush ("
TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
env->tlb_flush_addr, env->tlb_flush_mask);
tlb_flush(cpu, 1);
return;
}
addr &= TARGET_PAGE_MASK;
i = (addr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
tlb_flush_entry(&env->tlb_table[mmu_idx][i], addr);
}
/* check whether there are entries that need to be flushed in the vtlb */
for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
int k;
for (k = 0; k < CPU_VTLB_SIZE; k++) {
tlb_flush_entry(&env->tlb_v_table[mmu_idx][k], addr);
}
}
tb_flush_jmp_cache(cpu, addr);
}
void tlb_flush_page_by_mmuidx(CPUState *cpu, target_ulong addr, ...)
{
CPUArchState *env = cpu->env_ptr;
int i, k;
va_list argp;
va_start(argp, addr);
tlb_debug("addr "TARGET_FMT_lx"\n", addr);
/* Check if we need to flush due to large pages. */
if ((addr & env->tlb_flush_mask) == env->tlb_flush_addr) {
tlb_debug("forced full flush ("
TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
env->tlb_flush_addr, env->tlb_flush_mask);
v_tlb_flush_by_mmuidx(cpu, argp);
va_end(argp);
return;
}
addr &= TARGET_PAGE_MASK;
i = (addr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
for (;;) {
int mmu_idx = va_arg(argp, int);
if (mmu_idx < 0) {
break;
}
tlb_debug("idx %d\n", mmu_idx);
tlb_flush_entry(&env->tlb_table[mmu_idx][i], addr);
/* check whether there are vltb entries that need to be flushed */
for (k = 0; k < CPU_VTLB_SIZE; k++) {
tlb_flush_entry(&env->tlb_v_table[mmu_idx][k], addr);
}
}
va_end(argp);
tb_flush_jmp_cache(cpu, addr);
}
/* update the TLBs so that writes to code in the virtual page 'addr'
can be detected */
void tlb_protect_code(ram_addr_t ram_addr)
{
cpu_physical_memory_test_and_clear_dirty(ram_addr, TARGET_PAGE_SIZE,
DIRTY_MEMORY_CODE);
}
/* update the TLB so that writes in physical page 'phys_addr' are no longer
tested for self modifying code */
void tlb_unprotect_code(ram_addr_t ram_addr)
{
cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_CODE);
}
static bool tlb_is_dirty_ram(CPUTLBEntry *tlbe)
{
return (tlbe->addr_write & (TLB_INVALID_MASK|TLB_MMIO|TLB_NOTDIRTY)) == 0;
}
void tlb_reset_dirty_range(CPUTLBEntry *tlb_entry, uintptr_t start,
uintptr_t length)
{
uintptr_t addr;
if (tlb_is_dirty_ram(tlb_entry)) {
addr = (tlb_entry->addr_write & TARGET_PAGE_MASK) + tlb_entry->addend;
if ((addr - start) < length) {
tlb_entry->addr_write |= TLB_NOTDIRTY;
}
}
}
static inline ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr)
{
ram_addr_t ram_addr;
ram_addr = qemu_ram_addr_from_host(ptr);
if (ram_addr == RAM_ADDR_INVALID) {
fprintf(stderr, "Bad ram pointer %p\n", ptr);
abort();
}
return ram_addr;
}
void tlb_reset_dirty(CPUState *cpu, ram_addr_t start1, ram_addr_t length)
{
CPUArchState *env;
int mmu_idx;
env = cpu->env_ptr;
for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
unsigned int i;
for (i = 0; i < CPU_TLB_SIZE; i++) {
tlb_reset_dirty_range(&env->tlb_table[mmu_idx][i],
start1, length);
}
for (i = 0; i < CPU_VTLB_SIZE; i++) {
tlb_reset_dirty_range(&env->tlb_v_table[mmu_idx][i],
start1, length);
}
}
}
static inline void tlb_set_dirty1(CPUTLBEntry *tlb_entry, target_ulong vaddr)
{
if (tlb_entry->addr_write == (vaddr | TLB_NOTDIRTY)) {
tlb_entry->addr_write = vaddr;
}
}
/* update the TLB corresponding to virtual page vaddr
so that it is no longer dirty */
void tlb_set_dirty(CPUState *cpu, target_ulong vaddr)
{
CPUArchState *env = cpu->env_ptr;
int i;
int mmu_idx;
vaddr &= TARGET_PAGE_MASK;
i = (vaddr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
tlb_set_dirty1(&env->tlb_table[mmu_idx][i], vaddr);
}
for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
int k;
for (k = 0; k < CPU_VTLB_SIZE; k++) {
tlb_set_dirty1(&env->tlb_v_table[mmu_idx][k], vaddr);
}
}
}
/* Our TLB does not support large pages, so remember the area covered by
large pages and trigger a full TLB flush if these are invalidated. */
static void tlb_add_large_page(CPUArchState *env, target_ulong vaddr,
target_ulong size)
{
target_ulong mask = ~(size - 1);
if (env->tlb_flush_addr == (target_ulong)-1) {
env->tlb_flush_addr = vaddr & mask;
env->tlb_flush_mask = mask;
return;
}
/* Extend the existing region to include the new page.
This is a compromise between unnecessary flushes and the cost
of maintaining a full variable size TLB. */
mask &= env->tlb_flush_mask;
while (((env->tlb_flush_addr ^ vaddr) & mask) != 0) {
mask <<= 1;
}
env->tlb_flush_addr &= mask;
env->tlb_flush_mask = mask;
}
/* Add a new TLB entry. At most one entry for a given virtual address
* is permitted. Only a single TARGET_PAGE_SIZE region is mapped, the
* supplied size is only used by tlb_flush_page.
*
* Called from TCG-generated code, which is under an RCU read-side
* critical section.
*/
void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr,
hwaddr paddr, MemTxAttrs attrs, int prot,
int mmu_idx, target_ulong size)
{
CPUArchState *env = cpu->env_ptr;
MemoryRegionSection *section;
unsigned int index;
target_ulong address;
target_ulong code_address;
uintptr_t addend;
CPUTLBEntry *te;
hwaddr iotlb, xlat, sz;
unsigned vidx = env->vtlb_index++ % CPU_VTLB_SIZE;
int asidx = cpu_asidx_from_attrs(cpu, attrs);
assert(size >= TARGET_PAGE_SIZE);
if (size != TARGET_PAGE_SIZE) {
tlb_add_large_page(env, vaddr, size);
}
sz = size;
section = address_space_translate_for_iotlb(cpu, asidx, paddr, &xlat, &sz);
assert(sz >= TARGET_PAGE_SIZE);
tlb_debug("vaddr=" TARGET_FMT_lx " paddr=0x" TARGET_FMT_plx
" prot=%x idx=%d\n",
vaddr, paddr, prot, mmu_idx);
address = vaddr;
if (!memory_region_is_ram(section->mr) && !memory_region_is_romd(section->mr)) {
/* IO memory case */
address |= TLB_MMIO;
addend = 0;
} else {
/* TLB_MMIO for rom/romd handled below */
addend = (uintptr_t)memory_region_get_ram_ptr(section->mr) + xlat;
}
code_address = address;
iotlb = memory_region_section_get_iotlb(cpu, section, vaddr, paddr, xlat,
prot, &address);
index = (vaddr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
te = &env->tlb_table[mmu_idx][index];
/* do not discard the translation in te, evict it into a victim tlb */
env->tlb_v_table[mmu_idx][vidx] = *te;
env->iotlb_v[mmu_idx][vidx] = env->iotlb[mmu_idx][index];
/* refill the tlb */
env->iotlb[mmu_idx][index].addr = iotlb - vaddr;
env->iotlb[mmu_idx][index].attrs = attrs;
te->addend = addend - vaddr;
if (prot & PAGE_READ) {
te->addr_read = address;
} else {
te->addr_read = -1;
}
if (prot & PAGE_EXEC) {
te->addr_code = code_address;
} else {
te->addr_code = -1;
}
if (prot & PAGE_WRITE) {
if ((memory_region_is_ram(section->mr) && section->readonly)
|| memory_region_is_romd(section->mr)) {
/* Write access calls the I/O callback. */
te->addr_write = address | TLB_MMIO;
} else if (memory_region_is_ram(section->mr)
&& cpu_physical_memory_is_clean(
memory_region_get_ram_addr(section->mr) + xlat)) {
te->addr_write = address | TLB_NOTDIRTY;
} else {
te->addr_write = address;
}
} else {
te->addr_write = -1;
}
}
/* Add a new TLB entry, but without specifying the memory
* transaction attributes to be used.
*/
void tlb_set_page(CPUState *cpu, target_ulong vaddr,
hwaddr paddr, int prot,
int mmu_idx, target_ulong size)
{
tlb_set_page_with_attrs(cpu, vaddr, paddr, MEMTXATTRS_UNSPECIFIED,
prot, mmu_idx, size);
}
static void report_bad_exec(CPUState *cpu, target_ulong addr)
{
/* Accidentally executing outside RAM or ROM is quite common for
* several user-error situations, so report it in a way that
* makes it clear that this isn't a QEMU bug and provide suggestions
* about what a user could do to fix things.
*/
error_report("Trying to execute code outside RAM or ROM at 0x"
TARGET_FMT_lx, addr);
error_printf("This usually means one of the following happened:\n\n"
"(1) You told QEMU to execute a kernel for the wrong machine "
"type, and it crashed on startup (eg trying to run a "
"raspberry pi kernel on a versatilepb QEMU machine)\n"
"(2) You didn't give QEMU a kernel or BIOS filename at all, "
"and QEMU executed a ROM full of no-op instructions until "
"it fell off the end\n"
"(3) Your guest kernel has a bug and crashed by jumping "
"off into nowhere\n\n"
"This is almost always one of the first two, so check your "
"command line and that you are using the right type of kernel "
"for this machine.\n"
"If you think option (3) is likely then you can try debugging "
"your guest with the -d debug options; in particular "
"-d guest_errors will cause the log to include a dump of the "
"guest register state at this point.\n\n"
"Execution cannot continue; stopping here.\n\n");
/* Report also to the logs, with more detail including register dump */
qemu_log_mask(LOG_GUEST_ERROR, "qemu: fatal: Trying to execute code "
"outside RAM or ROM at 0x" TARGET_FMT_lx "\n", addr);
log_cpu_state_mask(LOG_GUEST_ERROR, cpu, CPU_DUMP_FPU | CPU_DUMP_CCOP);
}
/* NOTE: this function can trigger an exception */
/* NOTE2: the returned address is not exactly the physical address: it
* is actually a ram_addr_t (in system mode; the user mode emulation
* version of this function returns a guest virtual address).
*/
tb_page_addr_t get_page_addr_code(CPUArchState *env1, target_ulong addr)
{
int mmu_idx, page_index, pd;
void *p;
MemoryRegion *mr;
CPUState *cpu = ENV_GET_CPU(env1);
CPUIOTLBEntry *iotlbentry;
page_index = (addr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
mmu_idx = cpu_mmu_index(env1, true);
if (unlikely(env1->tlb_table[mmu_idx][page_index].addr_code !=
(addr & TARGET_PAGE_MASK))) {
cpu_ldub_code(env1, addr);
}
iotlbentry = &env1->iotlb[mmu_idx][page_index];
pd = iotlbentry->addr & ~TARGET_PAGE_MASK;
mr = iotlb_to_region(cpu, pd, iotlbentry->attrs);
if (memory_region_is_unassigned(mr)) {
CPUClass *cc = CPU_GET_CLASS(cpu);
if (cc->do_unassigned_access) {
cc->do_unassigned_access(cpu, addr, false, true, 0, 4);
} else {
report_bad_exec(cpu, addr);
exit(1);
}
}
p = (void *)((uintptr_t)addr + env1->tlb_table[mmu_idx][page_index].addend);
return qemu_ram_addr_from_host_nofail(p);
}
/* Return true if ADDR is present in the victim tlb, and has been copied
back to the main tlb. */
static bool victim_tlb_hit(CPUArchState *env, size_t mmu_idx, size_t index,
size_t elt_ofs, target_ulong page)
{
size_t vidx;
for (vidx = 0; vidx < CPU_VTLB_SIZE; ++vidx) {
CPUTLBEntry *vtlb = &env->tlb_v_table[mmu_idx][vidx];
target_ulong cmp = *(target_ulong *)((uintptr_t)vtlb + elt_ofs);
if (cmp == page) {
/* Found entry in victim tlb, swap tlb and iotlb. */
CPUTLBEntry tmptlb, *tlb = &env->tlb_table[mmu_idx][index];
CPUIOTLBEntry tmpio, *io = &env->iotlb[mmu_idx][index];
CPUIOTLBEntry *vio = &env->iotlb_v[mmu_idx][vidx];
tmptlb = *tlb; *tlb = *vtlb; *vtlb = tmptlb;
tmpio = *io; *io = *vio; *vio = tmpio;
return true;
}
}
return false;
}
/* Macro to call the above, with local variables from the use context. */
#define VICTIM_TLB_HIT(TY, ADDR) \
victim_tlb_hit(env, mmu_idx, index, offsetof(CPUTLBEntry, TY), \
(ADDR) & TARGET_PAGE_MASK)
#define MMUSUFFIX _mmu
#define SHIFT 0
#include "softmmu_template.h"
#define SHIFT 1
#include "softmmu_template.h"
#define SHIFT 2
#include "softmmu_template.h"
#define SHIFT 3
#include "softmmu_template.h"
#undef MMUSUFFIX
#define MMUSUFFIX _cmmu
#undef GETPC
#define GETPC() ((uintptr_t)0)
#define SOFTMMU_CODE_ACCESS
#define SHIFT 0
#include "softmmu_template.h"
#define SHIFT 1
#include "softmmu_template.h"
#define SHIFT 2
#include "softmmu_template.h"
#define SHIFT 3
#include "softmmu_template.h"