#define HOST_PAGE_ALIGN(addr) (((addr) + host_page_size - 1) & host_page_mask)
/* same as PROT_xxx */
-#define PAGE_READ 0x0001
-#define PAGE_WRITE 0x0002
-#define PAGE_EXEC 0x0004
-#define PAGE_BITS (PAGE_READ | PAGE_WRITE | PAGE_EXEC)
-#define PAGE_VALID 0x0008
+#define PAGE_READ 0x0001
+#define PAGE_WRITE 0x0002
+#define PAGE_EXEC 0x0004
+#define PAGE_BITS (PAGE_READ | PAGE_WRITE | PAGE_EXEC)
+#define PAGE_VALID 0x0008
+/* original state of the write flag (used when tracking self-modifying
+ code */
+#define PAGE_WRITE_ORG 0x0010
void page_dump(FILE *f);
int page_get_flags(unsigned long address);
void page_set_flags(unsigned long start, unsigned long end, int flags);
+void page_unprotect_range(uint8_t *data, unsigned long data_size);
+/***************************************************/
/* internal functions */
#define GEN_FLAG_CODE32_SHIFT 0
int cpu_x86_gen_code(uint8_t *gen_code_buf, int max_code_size,
int *gen_code_size_ptr,
- uint8_t *pc_start, uint8_t *cs_base, int flags);
+ uint8_t *pc_start, uint8_t *cs_base, int flags,
+ int *code_size_ptr);
void cpu_x86_tblocks_init(void);
void page_init(void);
+int page_unprotect(unsigned long address);
+
+#define CODE_GEN_MAX_SIZE 65536
+#define CODE_GEN_ALIGN 16 /* must be >= of the size of a icache line */
+
+#define CODE_GEN_HASH_BITS 15
+#define CODE_GEN_HASH_SIZE (1 << CODE_GEN_HASH_BITS)
+
+/* maximum total translate dcode allocated */
+#define CODE_GEN_BUFFER_SIZE (2048 * 1024)
+//#define CODE_GEN_BUFFER_SIZE (128 * 1024)
+
+typedef struct TranslationBlock {
+ unsigned long pc; /* simulated PC corresponding to this block (EIP + CS base) */
+ unsigned long cs_base; /* CS base for this block */
+ unsigned int flags; /* flags defining in which context the code was generated */
+ uint16_t size; /* size of target code for this block (1 <=
+ size <= TARGET_PAGE_SIZE) */
+ uint8_t *tc_ptr; /* pointer to the translated code */
+ struct TranslationBlock *hash_next; /* next matching block */
+ struct TranslationBlock *page_next[2]; /* next blocks in even/odd page */
+} TranslationBlock;
+
+static inline unsigned int tb_hash_func(unsigned long pc)
+{
+ return pc & (CODE_GEN_HASH_SIZE - 1);
+}
+
+void tb_flush(void);
+TranslationBlock *tb_alloc(unsigned long pc,
+ unsigned long size);
+
+extern TranslationBlock *tb_hash[CODE_GEN_HASH_SIZE];
+
+extern uint8_t code_gen_buffer[CODE_GEN_BUFFER_SIZE];
+extern uint8_t *code_gen_ptr;
+
+/* find a translation block in the translation cache. If not found,
+ return NULL and the pointer to the last element of the list in pptb */
+static inline TranslationBlock *tb_find(TranslationBlock ***pptb,
+ unsigned long pc,
+ unsigned long cs_base,
+ unsigned int flags)
+{
+ TranslationBlock **ptb, *tb;
+ unsigned int h;
+
+ h = tb_hash_func(pc);
+ ptb = &tb_hash[h];
+ for(;;) {
+ tb = *ptb;
+ if (!tb)
+ break;
+ if (tb->pc == pc && tb->cs_base == cs_base && tb->flags == flags)
+ return tb;
+ ptb = &tb->hash_next;
+ }
+ *pptb = ptb;
+ return NULL;
+}
+
+#ifndef offsetof
+#define offsetof(type, field) ((size_t) &((type *)0)->field)
+#endif
#endif /* CPU_I386_H */
#include "disas.h"
//#define DEBUG_EXEC
-#define DEBUG_FLUSH
//#define DEBUG_SIGNAL
/* main execution loop */
-/* maximum total translate dcode allocated */
-#define CODE_GEN_BUFFER_SIZE (2048 * 1024)
-//#define CODE_GEN_BUFFER_SIZE (128 * 1024)
-#define CODE_GEN_MAX_SIZE 65536
-#define CODE_GEN_ALIGN 16 /* must be >= of the size of a icache line */
-
-/* threshold to flush the translated code buffer */
-#define CODE_GEN_BUFFER_MAX_SIZE (CODE_GEN_BUFFER_SIZE - CODE_GEN_MAX_SIZE)
-
-#define CODE_GEN_MAX_BLOCKS (CODE_GEN_BUFFER_SIZE / 64)
-#define CODE_GEN_HASH_BITS 15
-#define CODE_GEN_HASH_SIZE (1 << CODE_GEN_HASH_BITS)
-
-typedef struct TranslationBlock {
- unsigned long pc; /* simulated PC corresponding to this block (EIP + CS base) */
- unsigned long cs_base; /* CS base for this block */
- unsigned int flags; /* flags defining in which context the code was generated */
- uint8_t *tc_ptr; /* pointer to the translated code */
- struct TranslationBlock *hash_next; /* next matching block */
-} TranslationBlock;
-
-TranslationBlock tbs[CODE_GEN_MAX_BLOCKS];
-TranslationBlock *tb_hash[CODE_GEN_HASH_SIZE];
-int nb_tbs;
-
-uint8_t code_gen_buffer[CODE_GEN_BUFFER_SIZE];
-uint8_t *code_gen_ptr;
-
/* thread support */
#ifdef __powerpc__
raise_exception_err(exception_index, 0);
}
-void cpu_x86_tblocks_init(void)
-{
- if (!code_gen_ptr) {
- code_gen_ptr = code_gen_buffer;
- }
-}
-
-/* flush all the translation blocks */
-static void tb_flush(void)
-{
- int i;
-#ifdef DEBUG_FLUSH
- printf("gemu: flush code_size=%d nb_tbs=%d avg_tb_size=%d\n",
- code_gen_ptr - code_gen_buffer,
- nb_tbs,
- (code_gen_ptr - code_gen_buffer) / nb_tbs);
-#endif
- nb_tbs = 0;
- for(i = 0;i < CODE_GEN_HASH_SIZE; i++)
- tb_hash[i] = NULL;
- code_gen_ptr = code_gen_buffer;
- /* XXX: flush processor icache at this point */
-}
-
-/* find a translation block in the translation cache. If not found,
- return NULL and the pointer to the last element of the list in pptb */
-static inline TranslationBlock *tb_find(TranslationBlock ***pptb,
- unsigned long pc,
- unsigned long cs_base,
- unsigned int flags)
-{
- TranslationBlock **ptb, *tb;
- unsigned int h;
-
- h = pc & (CODE_GEN_HASH_SIZE - 1);
- ptb = &tb_hash[h];
-#if 0
- /* XXX: hack to handle 16 bit modyfing code */
- if (flags & (1 << GEN_FLAG_CODE32_SHIFT))
-#endif
- for(;;) {
- tb = *ptb;
- if (!tb)
- break;
- if (tb->pc == pc && tb->cs_base == cs_base && tb->flags == flags)
- return tb;
- ptb = &tb->hash_next;
- }
- *pptb = ptb;
- return NULL;
-}
-
-/* allocate a new translation block. flush the translation buffer if
- too many translation blocks or too much generated code */
-static inline TranslationBlock *tb_alloc(void)
-{
- TranslationBlock *tb;
- if (nb_tbs >= CODE_GEN_MAX_BLOCKS ||
- (code_gen_ptr - code_gen_buffer) >= CODE_GEN_BUFFER_MAX_SIZE)
- tb_flush();
- tb = &tbs[nb_tbs++];
- return tb;
-}
-
int cpu_x86_exec(CPUX86State *env1)
{
int saved_T0, saved_T1, saved_A0;
#ifdef reg_EDI
int saved_EDI;
#endif
- int code_gen_size, ret;
+ int code_gen_size, ret, code_size;
void (*gen_func)(void);
TranslationBlock *tb, **ptb;
uint8_t *tc_ptr, *cs_base, *pc;
cpu_lock();
tc_ptr = code_gen_ptr;
ret = cpu_x86_gen_code(code_gen_ptr, CODE_GEN_MAX_SIZE,
- &code_gen_size, pc, cs_base, flags);
+ &code_gen_size, pc, cs_base, flags,
+ &code_size);
/* if invalid instruction, signal it */
if (ret != 0) {
cpu_unlock();
raise_exception(EXCP06_ILLOP);
}
- tb = tb_alloc();
+ tb = tb_alloc((unsigned long)pc, code_size);
*ptb = tb;
- tb->pc = (unsigned long)pc;
tb->cs_base = (unsigned long)cs_base;
tb->flags = flags;
tb->tc_ptr = tc_ptr;
#include <sys/ucontext.h>
/* 'pc' is the host PC at which the exception was raised. 'address' is
- the effective address of the memory exception */
+ the effective address of the memory exception. 'is_write' is 1 if a
+ write caused the exception and otherwise 0'. 'old_set' is the
+ signal set which should be restored */
static inline int handle_cpu_signal(unsigned long pc,
unsigned long address,
+ int is_write,
sigset_t *old_set)
{
-#ifdef DEBUG_SIGNAL
- printf("gemu: SIGSEGV pc=0x%08lx oldset=0x%08lx\n",
- pc, *(unsigned long *)old_set);
+#if defined(DEBUG_SIGNAL)
+ printf("qemu: SIGSEGV pc=0x%08lx address=%08lx wr=%d oldset=0x%08lx\n",
+ pc, address, is_write, *(unsigned long *)old_set);
#endif
+ if (is_write && page_unprotect(address)) {
+ sigprocmask(SIG_SETMASK, old_set, NULL);
+ return 1;
+ }
if (pc >= (unsigned long)code_gen_buffer &&
pc < (unsigned long)code_gen_buffer + CODE_GEN_BUFFER_SIZE) {
/* the PC is inside the translated code. It means that we have
/* XXX: need to compute virtual pc position by retranslating
code. The rest of the CPU state should be correct. */
env->cr2 = address;
- /* XXX: more precise exception code */
- raise_exception_err(EXCP0E_PAGE, 4);
+ raise_exception_err(EXCP0E_PAGE, 4 | (is_write << 1));
/* never comes here */
return 1;
} else {
#ifndef REG_EIP
/* for glibc 2.1 */
-#define REG_EIP EIP
+#define REG_EIP EIP
+#define REG_ERR ERR
+#define REG_TRAPNO TRAPNO
#endif
pc = uc->uc_mcontext.gregs[REG_EIP];
pold_set = &uc->uc_sigmask;
- return handle_cpu_signal(pc, (unsigned long)info->si_addr, pold_set);
+ return handle_cpu_signal(pc, (unsigned long)info->si_addr,
+ uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe ?
+ (uc->uc_mcontext.gregs[REG_ERR] >> 1) & 1 : 0,
+ pold_set);
#else
#warning No CPU specific signal handler: cannot handle target SIGSEGV events
return 0;
/*
- * virtual page mapping
+ * virtual page mapping and translated block handling
*
* Copyright (c) 2003 Fabrice Bellard
*
#include <errno.h>
#include <unistd.h>
#include <inttypes.h>
+#include <sys/mman.h>
#include "cpu-i386.h"
+//#define DEBUG_TB_INVALIDATE
+#define DEBUG_FLUSH
+
+/* make various TB consistency checks */
+//#define DEBUG_TB_CHECK
+
+/* threshold to flush the translated code buffer */
+#define CODE_GEN_BUFFER_MAX_SIZE (CODE_GEN_BUFFER_SIZE - CODE_GEN_MAX_SIZE)
+
+#define CODE_GEN_MAX_BLOCKS (CODE_GEN_BUFFER_SIZE / 64)
+
+TranslationBlock tbs[CODE_GEN_MAX_BLOCKS];
+TranslationBlock *tb_hash[CODE_GEN_HASH_SIZE];
+int nb_tbs;
+
+uint8_t code_gen_buffer[CODE_GEN_BUFFER_SIZE];
+uint8_t *code_gen_ptr;
+
/* XXX: pack the flags in the low bits of the pointer ? */
typedef struct PageDesc {
- struct TranslationBlock *first_tb;
unsigned long flags;
+ TranslationBlock *first_tb;
} PageDesc;
#define L2_BITS 10
#define L1_SIZE (1 << L1_BITS)
#define L2_SIZE (1 << L2_BITS)
+static void tb_invalidate_page(unsigned long address);
+
unsigned long real_host_page_size;
unsigned long host_page_bits;
unsigned long host_page_size;
}
}
-
-static inline PageDesc *page_find_alloc(unsigned long address)
+static inline PageDesc *page_find_alloc(unsigned int index)
{
- unsigned int index;
PageDesc **lp, *p;
- index = address >> TARGET_PAGE_BITS;
lp = &l1_map[index >> L2_BITS];
p = *lp;
if (!p) {
/* allocate if not found */
p = malloc(sizeof(PageDesc) * L2_SIZE);
- memset(p, 0, sizeof(sizeof(PageDesc) * L2_SIZE));
+ memset(p, 0, sizeof(PageDesc) * L2_SIZE);
*lp = p;
}
return p + (index & (L2_SIZE - 1));
}
-int page_get_flags(unsigned long address)
+static inline PageDesc *page_find(unsigned int index)
{
- unsigned int index;
PageDesc *p;
- index = address >> TARGET_PAGE_BITS;
p = l1_map[index >> L2_BITS];
if (!p)
return 0;
- return p[index & (L2_SIZE - 1)].flags;
+ return p + (index & (L2_SIZE - 1));
+}
+
+int page_get_flags(unsigned long address)
+{
+ PageDesc *p;
+
+ p = page_find(address >> TARGET_PAGE_BITS);
+ if (!p)
+ return 0;
+ return p->flags;
}
+/* modify the flags of a page and invalidate the code if
+ necessary. The flag PAGE_WRITE_ORG is positionned automatically
+ depending on PAGE_WRITE */
void page_set_flags(unsigned long start, unsigned long end, int flags)
{
PageDesc *p;
start = start & TARGET_PAGE_MASK;
end = TARGET_PAGE_ALIGN(end);
+ if (flags & PAGE_WRITE)
+ flags |= PAGE_WRITE_ORG;
for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) {
- p = page_find_alloc(addr);
+ p = page_find_alloc(addr >> TARGET_PAGE_BITS);
+ /* if the write protection is set, then we invalidate the code
+ inside */
+ if (!(p->flags & PAGE_WRITE) &&
+ (flags & PAGE_WRITE) &&
+ p->first_tb) {
+ tb_invalidate_page(addr);
+ }
p->flags = flags;
}
}
+
+void cpu_x86_tblocks_init(void)
+{
+ if (!code_gen_ptr) {
+ code_gen_ptr = code_gen_buffer;
+ }
+}
+
+/* set to NULL all the 'first_tb' fields in all PageDescs */
+static void page_flush_tb(void)
+{
+ int i, j;
+ PageDesc *p;
+
+ for(i = 0; i < L1_SIZE; i++) {
+ p = l1_map[i];
+ if (p) {
+ for(j = 0; j < L2_SIZE; j++)
+ p[j].first_tb = NULL;
+ }
+ }
+}
+
+/* flush all the translation blocks */
+void tb_flush(void)
+{
+ int i;
+#ifdef DEBUG_FLUSH
+ printf("qemu: flush code_size=%d nb_tbs=%d avg_tb_size=%d\n",
+ code_gen_ptr - code_gen_buffer,
+ nb_tbs,
+ (code_gen_ptr - code_gen_buffer) / nb_tbs);
+#endif
+ nb_tbs = 0;
+ for(i = 0;i < CODE_GEN_HASH_SIZE; i++)
+ tb_hash[i] = NULL;
+ page_flush_tb();
+ code_gen_ptr = code_gen_buffer;
+ /* XXX: flush processor icache at this point */
+}
+
+#ifdef DEBUG_TB_CHECK
+
+static void tb_invalidate_check(unsigned long address)
+{
+ TranslationBlock *tb;
+ int i;
+ address &= TARGET_PAGE_MASK;
+ for(i = 0;i < CODE_GEN_HASH_SIZE; i++) {
+ for(tb = tb_hash[i]; tb != NULL; tb = tb->hash_next) {
+ if (!(address + TARGET_PAGE_SIZE <= tb->pc ||
+ address >= tb->pc + tb->size)) {
+ printf("ERROR invalidate: address=%08lx PC=%08lx size=%04x\n",
+ address, tb->pc, tb->size);
+ }
+ }
+ }
+}
+
+/* verify that all the pages have correct rights for code */
+static void tb_page_check(void)
+{
+ TranslationBlock *tb;
+ int i, flags1, flags2;
+
+ for(i = 0;i < CODE_GEN_HASH_SIZE; i++) {
+ for(tb = tb_hash[i]; tb != NULL; tb = tb->hash_next) {
+ flags1 = page_get_flags(tb->pc);
+ flags2 = page_get_flags(tb->pc + tb->size - 1);
+ if ((flags1 & PAGE_WRITE) || (flags2 & PAGE_WRITE)) {
+ printf("ERROR page flags: PC=%08lx size=%04x f1=%x f2=%x\n",
+ tb->pc, tb->size, flags1, flags2);
+ }
+ }
+ }
+}
+
+#endif
+
+/* invalidate one TB */
+static inline void tb_remove(TranslationBlock **ptb, TranslationBlock *tb,
+ int next_offset)
+{
+ TranslationBlock *tb1;
+ for(;;) {
+ tb1 = *ptb;
+ if (tb1 == tb) {
+ *ptb = *(TranslationBlock **)((char *)tb1 + next_offset);
+ break;
+ }
+ ptb = (TranslationBlock **)((char *)tb1 + next_offset);
+ }
+}
+
+static inline void tb_invalidate(TranslationBlock *tb, int parity)
+{
+ PageDesc *p;
+ unsigned int page_index1, page_index2;
+ unsigned int h;
+
+ /* remove the TB from the hash list */
+ h = tb_hash_func(tb->pc);
+ tb_remove(&tb_hash[h], tb,
+ offsetof(TranslationBlock, hash_next));
+ /* remove the TB from the page list */
+ page_index1 = tb->pc >> TARGET_PAGE_BITS;
+ if ((page_index1 & 1) == parity) {
+ p = page_find(page_index1);
+ tb_remove(&p->first_tb, tb,
+ offsetof(TranslationBlock, page_next[page_index1 & 1]));
+ }
+ page_index2 = (tb->pc + tb->size - 1) >> TARGET_PAGE_BITS;
+ if ((page_index2 & 1) == parity) {
+ p = page_find(page_index2);
+ tb_remove(&p->first_tb, tb,
+ offsetof(TranslationBlock, page_next[page_index2 & 1]));
+ }
+}
+
+/* invalidate all TBs which intersect with the target page starting at addr */
+static void tb_invalidate_page(unsigned long address)
+{
+ TranslationBlock *tb_next, *tb;
+ unsigned int page_index;
+ int parity1, parity2;
+ PageDesc *p;
+#ifdef DEBUG_TB_INVALIDATE
+ printf("tb_invalidate_page: %lx\n", address);
+#endif
+
+ page_index = address >> TARGET_PAGE_BITS;
+ p = page_find(page_index);
+ if (!p)
+ return;
+ tb = p->first_tb;
+ parity1 = page_index & 1;
+ parity2 = parity1 ^ 1;
+ while (tb != NULL) {
+ tb_next = tb->page_next[parity1];
+ tb_invalidate(tb, parity2);
+ tb = tb_next;
+ }
+ p->first_tb = NULL;
+}
+
+/* add the tb in the target page and protect it if necessary */
+static inline void tb_alloc_page(TranslationBlock *tb, unsigned int page_index)
+{
+ PageDesc *p;
+ unsigned long host_start, host_end, addr, page_addr;
+ int prot;
+
+ p = page_find_alloc(page_index);
+ tb->page_next[page_index & 1] = p->first_tb;
+ p->first_tb = tb;
+ if (p->flags & PAGE_WRITE) {
+ /* force the host page as non writable (writes will have a
+ page fault + mprotect overhead) */
+ page_addr = (page_index << TARGET_PAGE_BITS);
+ host_start = page_addr & host_page_mask;
+ host_end = host_start + host_page_size;
+ prot = 0;
+ for(addr = host_start; addr < host_end; addr += TARGET_PAGE_SIZE)
+ prot |= page_get_flags(addr);
+ mprotect((void *)host_start, host_page_size,
+ (prot & PAGE_BITS) & ~PAGE_WRITE);
+#ifdef DEBUG_TB_INVALIDATE
+ printf("protecting code page: 0x%08lx\n",
+ host_start);
+#endif
+ p->flags &= ~PAGE_WRITE;
+#ifdef DEBUG_TB_CHECK
+ tb_page_check();
+#endif
+ }
+}
+
+/* Allocate a new translation block. Flush the translation buffer if
+ too many translation blocks or too much generated code. */
+TranslationBlock *tb_alloc(unsigned long pc,
+ unsigned long size)
+{
+ TranslationBlock *tb;
+ unsigned int page_index1, page_index2;
+
+ if (nb_tbs >= CODE_GEN_MAX_BLOCKS ||
+ (code_gen_ptr - code_gen_buffer) >= CODE_GEN_BUFFER_MAX_SIZE)
+ tb_flush();
+ tb = &tbs[nb_tbs++];
+ tb->pc = pc;
+ tb->size = size;
+
+ /* add in the page list */
+ page_index1 = pc >> TARGET_PAGE_BITS;
+ tb_alloc_page(tb, page_index1);
+ page_index2 = (pc + size - 1) >> TARGET_PAGE_BITS;
+ if (page_index2 != page_index1) {
+ tb_alloc_page(tb, page_index2);
+ }
+ return tb;
+}
+
+/* called from signal handler: invalidate the code and unprotect the
+ page. Return TRUE if the fault was succesfully handled. */
+int page_unprotect(unsigned long address)
+{
+ unsigned int page_index, prot;
+ PageDesc *p;
+ unsigned long host_start, host_end, addr;
+
+ page_index = address >> TARGET_PAGE_BITS;
+ p = page_find(page_index);
+ if (!p)
+ return 0;
+ if ((p->flags & (PAGE_WRITE_ORG | PAGE_WRITE)) == PAGE_WRITE_ORG) {
+ /* if the page was really writable, then we change its
+ protection back to writable */
+ host_start = address & host_page_mask;
+ host_end = host_start + host_page_size;
+ prot = 0;
+ for(addr = host_start; addr < host_end; addr += TARGET_PAGE_SIZE)
+ prot |= page_get_flags(addr);
+ mprotect((void *)host_start, host_page_size,
+ (prot & PAGE_BITS) | PAGE_WRITE);
+ p->flags |= PAGE_WRITE;
+
+ /* and since the content will be modified, we must invalidate
+ the corresponding translated code. */
+ tb_invalidate_page(address);
+#ifdef DEBUG_TB_CHECK
+ tb_invalidate_check(address);
+#endif
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+/* call this function when system calls directly modify a memory area */
+void page_unprotect_range(uint8_t *data, unsigned long data_size)
+{
+ unsigned long start, end, addr;
+
+ start = (unsigned long)data;
+ end = start + data_size;
+ start &= TARGET_PAGE_MASK;
+ end = TARGET_PAGE_ALIGN(end);
+ for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) {
+ page_unprotect(addr);
+ }
+}
projects / mirror_qemu.git / commitdiff