exec.c

qemu虚拟机代码

#endif
            return 1;
        }
    }
    return 0;
}

/* call this function when system calls directly modify a memory area */
/* ??? This should be redundant now we have lock_user.  */
void page_unprotect_range(target_ulong data, target_ulong data_size)
{
    target_ulong start, end, addr;

    start = 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, 0, NULL);
    }
}

static inline void tlb_set_dirty(CPUState *env,
                                 unsigned long addr, target_ulong vaddr)
{
}
#endif /* defined(CONFIG_USER_ONLY) */

/* register physical memory. 'size' must be a multiple of the target
   page size. If (phys_offset & ~TARGET_PAGE_MASK) != 0, then it is an
   io memory page */
void cpu_register_physical_memory(target_phys_addr_t start_addr, 
                                  unsigned long size,
                                  unsigned long phys_offset)
{
    target_phys_addr_t addr, end_addr;
    PhysPageDesc *p;

    size = (size + TARGET_PAGE_SIZE - 1) & TARGET_PAGE_MASK;
    end_addr = start_addr + size;
    for(addr = start_addr; addr != end_addr; addr += TARGET_PAGE_SIZE) {
        p = phys_page_find_alloc(addr >> TARGET_PAGE_BITS, 1);
        p->phys_offset = phys_offset;
        if ((phys_offset & ~TARGET_PAGE_MASK) <= IO_MEM_ROM)
            phys_offset += TARGET_PAGE_SIZE;
    }
}

static uint32_t unassigned_mem_readb(void *opaque, target_phys_addr_t addr)
{
    return 0;
}

static void unassigned_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)
{
}

static CPUReadMemoryFunc *unassigned_mem_read[3] = {
    unassigned_mem_readb,
    unassigned_mem_readb,
    unassigned_mem_readb,
};

static CPUWriteMemoryFunc *unassigned_mem_write[3] = {
    unassigned_mem_writeb,
    unassigned_mem_writeb,
    unassigned_mem_writeb,
};

static void notdirty_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)
{
    unsigned long ram_addr;
    int dirty_flags;
    ram_addr = addr - (unsigned long)phys_ram_base;
    dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
    if (!(dirty_flags & CODE_DIRTY_FLAG)) {
#if !defined(CONFIG_USER_ONLY)
        tb_invalidate_phys_page_fast(ram_addr, 1);
        dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
#endif
    }
    stb_p((uint8_t *)(long)addr, val);
#ifdef USE_KQEMU
    if (cpu_single_env->kqemu_enabled &&
        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
        kqemu_modify_page(cpu_single_env, ram_addr);
#endif
    dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
    phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
    /* we remove the notdirty callback only if the code has been
       flushed */
    if (dirty_flags == 0xff)
        tlb_set_dirty(cpu_single_env, addr, cpu_single_env->mem_write_vaddr);
}

static void notdirty_mem_writew(void *opaque, target_phys_addr_t addr, uint32_t val)
{
    unsigned long ram_addr;
    int dirty_flags;
    ram_addr = addr - (unsigned long)phys_ram_base;
    dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
    if (!(dirty_flags & CODE_DIRTY_FLAG)) {
#if !defined(CONFIG_USER_ONLY)
        tb_invalidate_phys_page_fast(ram_addr, 2);
        dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
#endif
    }
    stw_p((uint8_t *)(long)addr, val);
#ifdef USE_KQEMU
    if (cpu_single_env->kqemu_enabled &&
        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
        kqemu_modify_page(cpu_single_env, ram_addr);
#endif
    dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
    phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
    /* we remove the notdirty callback only if the code has been
       flushed */
    if (dirty_flags == 0xff)
        tlb_set_dirty(cpu_single_env, addr, cpu_single_env->mem_write_vaddr);
}

static void notdirty_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)
{
    unsigned long ram_addr;
    int dirty_flags;
    ram_addr = addr - (unsigned long)phys_ram_base;
    dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
    if (!(dirty_flags & CODE_DIRTY_FLAG)) {
#if !defined(CONFIG_USER_ONLY)
        tb_invalidate_phys_page_fast(ram_addr, 4);
        dirty_flags = phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS];
#endif
    }
    stl_p((uint8_t *)(long)addr, val);
#ifdef USE_KQEMU
    if (cpu_single_env->kqemu_enabled &&
        (dirty_flags & KQEMU_MODIFY_PAGE_MASK) != KQEMU_MODIFY_PAGE_MASK)
        kqemu_modify_page(cpu_single_env, ram_addr);
#endif
    dirty_flags |= (0xff & ~CODE_DIRTY_FLAG);
    phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] = dirty_flags;
    /* we remove the notdirty callback only if the code has been
       flushed */
    if (dirty_flags == 0xff)
        tlb_set_dirty(cpu_single_env, addr, cpu_single_env->mem_write_vaddr);
}

static CPUReadMemoryFunc *error_mem_read[3] = {
    NULL, /* never used */
    NULL, /* never used */
    NULL, /* never used */
};

static CPUWriteMemoryFunc *notdirty_mem_write[3] = {
    notdirty_mem_writeb,
    notdirty_mem_writew,
    notdirty_mem_writel,
};

static void io_mem_init(void)
{
    cpu_register_io_memory(IO_MEM_ROM >> IO_MEM_SHIFT, error_mem_read, unassigned_mem_write, NULL);
    cpu_register_io_memory(IO_MEM_UNASSIGNED >> IO_MEM_SHIFT, unassigned_mem_read, unassigned_mem_write, NULL);
    cpu_register_io_memory(IO_MEM_NOTDIRTY >> IO_MEM_SHIFT, error_mem_read, notdirty_mem_write, NULL);
    io_mem_nb = 5;

    /* alloc dirty bits array */
    phys_ram_dirty = qemu_vmalloc(phys_ram_size >> TARGET_PAGE_BITS);
    memset(phys_ram_dirty, 0xff, phys_ram_size >> TARGET_PAGE_BITS);
}

/* mem_read and mem_write are arrays of functions containing the
   function to access byte (index 0), word (index 1) and dword (index
   2). All functions must be supplied. If io_index is non zero, the
   corresponding io zone is modified. If it is zero, a new io zone is
   allocated. The return value can be used with
   cpu_register_physical_memory(). (-1) is returned if error. */
int cpu_register_io_memory(int io_index,
                           CPUReadMemoryFunc **mem_read,
                           CPUWriteMemoryFunc **mem_write,
                           void *opaque)
{
    int i;

    if (io_index <= 0) {
        if (io_mem_nb >= IO_MEM_NB_ENTRIES)
            return -1;
        io_index = io_mem_nb++;
    } else {
        if (io_index >= IO_MEM_NB_ENTRIES)
            return -1;
    }

    for(i = 0;i < 3; i++) {
        io_mem_read[io_index][i] = mem_read[i];
        io_mem_write[io_index][i] = mem_write[i];
    }
    io_mem_opaque[io_index] = opaque;
    return io_index << IO_MEM_SHIFT;
}

CPUWriteMemoryFunc **cpu_get_io_memory_write(int io_index)
{
    return io_mem_write[io_index >> IO_MEM_SHIFT];
}

CPUReadMemoryFunc **cpu_get_io_memory_read(int io_index)
{
    return io_mem_read[io_index >> IO_MEM_SHIFT];
}

/* physical memory access (slow version, mainly for debug) */
#if defined(CONFIG_USER_ONLY)
void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf, 
                            int len, int is_write)
{
    int l, flags;
    target_ulong page;
    void * p;

    while (len > 0) {
        page = addr & TARGET_PAGE_MASK;
        l = (page + TARGET_PAGE_SIZE) - addr;
        if (l > len)
            l = len;
        flags = page_get_flags(page);
        if (!(flags & PAGE_VALID))
            return;
        if (is_write) {
            if (!(flags & PAGE_WRITE))
                return;
            p = lock_user(addr, len, 0);
            memcpy(p, buf, len);
            unlock_user(p, addr, len);
        } else {
            if (!(flags & PAGE_READ))
                return;
            p = lock_user(addr, len, 1);
            memcpy(buf, p, len);
            unlock_user(p, addr, 0);
        }
        len -= l;
        buf += l;
        addr += l;
    }
}

#else
void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf, 
                            int len, int is_write)
{
    int l, io_index;
    uint8_t *ptr;
    uint32_t val;
    target_phys_addr_t page;
    unsigned long pd;
    PhysPageDesc *p;
    
    while (len > 0) {
        page = addr & TARGET_PAGE_MASK;
        l = (page + TARGET_PAGE_SIZE) - addr;
        if (l > len)
            l = len;
        p = phys_page_find(page >> TARGET_PAGE_BITS);
        if (!p) {
            pd = IO_MEM_UNASSIGNED;
        } else {
            pd = p->phys_offset;
        }
        
        if (is_write) {
            if ((pd & ~TARGET_PAGE_MASK) != IO_MEM_RAM) {
                io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
                /* XXX: could force cpu_single_env to NULL to avoid
                   potential bugs */
                if (l >= 4 && ((addr & 3) == 0)) {
                    /* 32 bit write access */
                    val = ldl_p(buf);
                    io_mem_write[io_index][2](io_mem_opaque[io_index], addr, val);
                    l = 4;
                } else if (l >= 2 && ((addr & 1) == 0)) {
                    /* 16 bit write access */
                    val = lduw_p(buf);
                    io_mem_write[io_index][1](io_mem_opaque[io_index], addr, val);
                    l = 2;
                } else {
                    /* 8 bit write access */
                    val = ldub_p(buf);
                    io_mem_write[io_index][0](io_mem_opaque[io_index], addr, val);
                    l = 1;
                }
            } else {
                unsigned long addr1;
                addr1 = (pd & TARGET_PAGE_MASK) + (addr & ~TARGET_PAGE_MASK);
                /* RAM case */
                ptr = phys_ram_base + addr1;
                memcpy(ptr, buf, l);
                if (!cpu_physical_memory_is_dirty(addr1)) {
                    /* invalidate code */
                    tb_invalidate_phys_page_range(addr1, addr1 + l, 0);
                    /* set dirty bit */
                    phys_ram_dirty[addr1 >> TARGET_PAGE_BITS] |= 
                        (0xff & ~CODE_DIRTY_FLAG);
                }
            }
        } else {
            if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {
                /* I/O case */
                io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
                if (l >= 4 && ((addr & 3) == 0)) {
                    /* 32 bit read access */
                    val = io_mem_read[io_index][2](io_mem_opaque[io_index], addr);
                    stl_p(buf, val);
                    l = 4;
                } else if (l >= 2 && ((addr & 1) == 0)) {
                    /* 16 bit read access */
                    val = io_mem_read[io_index][1](io_mem_opaque[io_index], addr);
                    stw_p(buf, val);
                    l = 2;
                } else {
                    /* 8 bit read access */
                    val = io_mem_read[io_index][0](io_mem_opaque[io_index], addr);
                    stb_p(buf, val);
                    l = 1;
                }
            } else {
                /* RAM case */
                ptr = phys_ram_base + (pd & TARGET_PAGE_MASK) + 
                    (addr & ~TARGET_PAGE_MASK);
                memcpy(buf, ptr, l);
            }
        }
        len -= l;
        buf += l;
        addr += l;
    }
}

/* used for ROM loading : can write in RAM and ROM */
void cpu_physical_memory_write_rom(target_phys_addr_t addr, 
                                   const uint8_t *buf, int len)
{
    int l;
    uint8_t *ptr;
    target_phys_addr_t page;
    unsigned long pd;
    PhysPageDesc *p;
    
    while (len > 0) {
        page = addr & TARGET_PAGE_MASK;
        l = (page + TARGET_PAGE_SIZE) - addr;
        if (l > len)
            l = len;
        p = phys_page_find(page >> TARGET_PAGE_BITS);
        if (!p) {
            pd = IO_MEM_UNASSIGNED;
        } else {
            pd = p->phys_offset;
        }
        
        if ((pd & ~TARGET_PAGE_MASK) != IO_MEM_RAM &&
            (pd & ~TARGET_PAGE_MASK) != IO_MEM_ROM) {
            /* do nothing */
        } else {
            unsigned long addr1;
            addr1 = (pd & TARGET_PAGE_MASK) + (addr & ~TARGET_PAGE_MASK);
            /* ROM/RAM case */
            ptr = phys_ram_base + addr1;
            memcpy(ptr, buf, l);
        }
        len -= l;
        buf += l;
        addr += l;
    }
}


/* warning: addr must be aligned */
uint32_t ldl_phys(target_phys_addr_t addr)
{
    int io_index;
    uint8_t *ptr;
    uint32_t val;
    unsigned long pd;
    PhysPageDesc *p;

    p = phys_page_find(addr >> TARGET_PAGE_BITS);
    if (!p) {
        pd = IO_MEM_UNASSIGNED;
    } else {
        pd = p->phys_offset;
    }
        
    if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {
        /* I/O case */
        io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
        val = io_mem_read[io_index][2](io_mem_opaque[io_index], addr);
    } else {
        /* RAM case */
        ptr = phys_ram_base + (pd & TARGET_PAGE_MASK) + 
            (addr & ~TARGET_PAGE_MASK);
        val = ldl_p(ptr);
    }
    return val;
}

/* warning: addr must be aligned */
uint64_t ldq_phys(target_phys_addr_t addr)
{
    int io_index;
    uint8_t *ptr;
    uint64_t val;
    unsigned long pd;
    PhysPageDesc *p;

    p = phys_page_find(addr >> TARGET_PAGE_BITS);
    if (!p) {
        pd = IO_MEM_UNASSIGNED;
    } else {
        pd = p->phys_offset;
    }
        
    if ((pd & ~TARGET_PAGE_MASK) > IO_MEM_ROM) {
        /* I/O case */
        io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
#ifdef TARGET_WORDS_BIGENDIAN
        val = (uint64_t)io_mem_read[io_index][2](io_mem_opaque[io_index], addr) << 32;
        val |= io_mem_read[io_index][2](io_mem_opaque[io_index], addr + 4);
#else
        val = io_mem_read[io_index][2](io_mem_opaque[io_index], addr);
        val |= (uint64_t)io_mem_read[io_index][2](io_mem_opaque[io_index], addr + 4) << 32;
#endif
    } else {
        /* RAM case */