include/exec/ram_addr.h - qemu - Git at Google

 /*
  * 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 "cpu.h"
 #include "sysemu/xen.h"
 #include "sysemu/tcg.h"
 #include "exec/ramlist.h"
 #include "exec/ramblock.h"

 extern uint64_t total_dirty_pages;

 /**
  * clear_bmap_size: calculate clear bitmap size
  *
  * @pages: number of guest pages
  * @shift: guest page number shift
  *
  * Returns: number of bits for the clear bitmap
  */
 static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
 {
     return DIV_ROUND_UP(pages, 1UL << shift);
 }

 /**
  * clear_bmap_set: set clear bitmap for the page range
  *
  * @rb: the ramblock to operate on
  * @start: the start page number
  * @size: number of pages to set in the bitmap
  *
  * Returns: None
  */
 static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
                                   uint64_t npages)
 {
     uint8_t shift = rb->clear_bmap_shift;

     bitmap_set_atomic(rb->clear_bmap, start >> shift,
                       clear_bmap_size(npages, shift));
 }

 /**
  * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set
  *
  * @rb: the ramblock to operate on
  * @page: the page number to check
  *
  * Returns: true if the bit was set, false otherwise
  */
 static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
 {
     uint8_t shift = rb->clear_bmap_shift;

     return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1);
 }

 static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
 {
     return (b && b->host && offset < b->used_length) ? true : false;
 }

 static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
 {
     assert(offset_in_ramblock(block, offset));
     return (char *)block->host + offset;
 }

 static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
                                                             RAMBlock *rb)
 {
     uint64_t host_addr_offset =
             (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
     return host_addr_offset >> TARGET_PAGE_BITS;
 }

 bool ramblock_is_pmem(RAMBlock *rb);

 long qemu_minrampagesize(void);
 long qemu_maxrampagesize(void);

 /**
  * qemu_ram_alloc_from_file,
  * qemu_ram_alloc_from_fd:  Allocate a ram block from the specified backing
  *                          file or device
  *
  * Parameters:
  *  @size: the size in bytes of the ram block
  *  @mr: the memory region where the ram block is
  *  @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
  *              RAM_NORESERVE.
  *  @mem_path or @fd: specify the backing file or device
  *  @readonly: true to open @path for reading, false for read/write.
  *  @errp: pointer to Error*, to store an error if it happens
  *
  * Return:
  *  On success, return a pointer to the ram block.
  *  On failure, return NULL.
  */
 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
                                    uint32_t ram_flags, const char *mem_path,
                                    bool readonly, Error **errp);
 RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
                                  uint32_t ram_flags, int fd, off_t offset,
                                  bool readonly, Error **errp);

 RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
                                   MemoryRegion *mr, Error **errp);
 RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags, MemoryRegion *mr,
                          Error **errp);
 RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
                                     void (*resized)(const char*,
                                                     uint64_t length,
                                                     void *host),
                                     MemoryRegion *mr, Error **errp);
 void qemu_ram_free(RAMBlock *block);

 int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp);

 void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length);

 /* Clear whole block of mem */
 static inline void qemu_ram_block_writeback(RAMBlock *block)
 {
     qemu_ram_msync(block, 0, block->used_length);
 }

 #define DIRTY_CLIENTS_ALL     ((1 << DIRTY_MEMORY_NUM) - 1)
 #define DIRTY_CLIENTS_NOCODE  (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))

 static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
                                                  ram_addr_t length,
                                                  unsigned client)
 {
     DirtyMemoryBlocks *blocks;
     unsigned long end, page;
     unsigned long idx, offset, base;
     bool dirty = false;

     assert(client < DIRTY_MEMORY_NUM);

     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
     page = start >> TARGET_PAGE_BITS;

     WITH_RCU_READ_LOCK_GUARD() {
         blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

         idx = page / DIRTY_MEMORY_BLOCK_SIZE;
         offset = page % DIRTY_MEMORY_BLOCK_SIZE;
         base = page - offset;
         while (page < end) {
             unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
             unsigned long num = next - base;
             unsigned long found = find_next_bit(blocks->blocks[idx],
                                                 num, offset);
             if (found < num) {
                 dirty = true;
                 break;
             }

             page = next;
             idx++;
             offset = 0;
             base += DIRTY_MEMORY_BLOCK_SIZE;
         }
     }

     return dirty;
 }

 static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
                                                  ram_addr_t length,
                                                  unsigned client)
 {
     DirtyMemoryBlocks *blocks;
     unsigned long end, page;
     unsigned long idx, offset, base;
     bool dirty = true;

     assert(client < DIRTY_MEMORY_NUM);

     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
     page = start >> TARGET_PAGE_BITS;

     RCU_READ_LOCK_GUARD();

     blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

     idx = page / DIRTY_MEMORY_BLOCK_SIZE;
     offset = page % DIRTY_MEMORY_BLOCK_SIZE;
     base = page - offset;
     while (page < end) {
         unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
         unsigned long num = next - base;
         unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
         if (found < num) {
             dirty = false;
             break;
         }

         page = next;
         idx++;
         offset = 0;
         base += DIRTY_MEMORY_BLOCK_SIZE;
     }

     return dirty;
 }

 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 uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
                                                                ram_addr_t length,
                                                                uint8_t mask)
 {
     uint8_t ret = 0;

     if (mask & (1 << DIRTY_MEMORY_VGA) &&
         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
         ret |= (1 << DIRTY_MEMORY_VGA);
     }
     if (mask & (1 << DIRTY_MEMORY_CODE) &&
         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
         ret |= (1 << DIRTY_MEMORY_CODE);
     }
     if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
         ret |= (1 << DIRTY_MEMORY_MIGRATION);
     }
     return ret;
 }

 static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
                                                       unsigned client)
 {
     unsigned long page, idx, offset;
     DirtyMemoryBlocks *blocks;

     assert(client < DIRTY_MEMORY_NUM);

     page = addr >> TARGET_PAGE_BITS;
     idx = page / DIRTY_MEMORY_BLOCK_SIZE;
     offset = page % DIRTY_MEMORY_BLOCK_SIZE;

     RCU_READ_LOCK_GUARD();

     blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

     set_bit_atomic(offset, blocks->blocks[idx]);
 }

 static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
                                                        ram_addr_t length,
                                                        uint8_t mask)
 {
     DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
     unsigned long end, page;
     unsigned long idx, offset, base;
     int i;

     if (!mask && !xen_enabled()) {
         return;
     }

     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
     page = start >> TARGET_PAGE_BITS;

     WITH_RCU_READ_LOCK_GUARD() {
         for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
             blocks[i] = qatomic_rcu_read(&ram_list.dirty_memory[i]);
         }

         idx = page / DIRTY_MEMORY_BLOCK_SIZE;
         offset = page % DIRTY_MEMORY_BLOCK_SIZE;
         base = page - offset;
         while (page < end) {
             unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);

             if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
                 bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
                                   offset, next - page);
             }
             if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
                 bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
                                   offset, next - page);
             }
             if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
                 bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
                                   offset, next - page);
             }

             page = next;
             idx++;
             offset = 0;
             base += DIRTY_MEMORY_BLOCK_SIZE;
         }
     }

     xen_hvm_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 = qemu_real_host_page_size() / 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)) {
         unsigned long **blocks[DIRTY_MEMORY_NUM];
         unsigned long idx;
         unsigned long offset;
         long k;
         long nr = BITS_TO_LONGS(pages);

         idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
         offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
                           DIRTY_MEMORY_BLOCK_SIZE);

         WITH_RCU_READ_LOCK_GUARD() {
             for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
                 blocks[i] =
                     qatomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
             }

             for (k = 0; k < nr; k++) {
                 if (bitmap[k]) {
                     unsigned long temp = leul_to_cpu(bitmap[k]);

                     qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);

                     if (global_dirty_tracking) {
                         qatomic_or(
                                 &blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
                                 temp);
                         if (unlikely(
                             global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
                             total_dirty_pages += ctpopl(temp);
                         }
                     }

                     if (tcg_enabled()) {
                         qatomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset],
                                    temp);
                     }
                 }

                 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
                     offset = 0;
                     idx++;
                 }
             }
         }

         xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
     } else {
         uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;

         if (!global_dirty_tracking) {
             clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
         }

         /*
          * 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]);
                 if (unlikely(global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
                     total_dirty_pages += ctpopl(c);
                 }
                 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, clients);
                 } while (c != 0);
             }
         }
     }
 }
 #endif /* not _WIN32 */

 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
                                               ram_addr_t length,
                                               unsigned client);

 DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
     (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);

 bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
                                             ram_addr_t start,
                                             ram_addr_t length);

 static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
                                                          ram_addr_t length)
 {
     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
 }


 /* Called with RCU critical section */
 static inline
 uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
                                                ram_addr_t start,
                                                ram_addr_t length)
 {
     ram_addr_t addr;
     unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
     uint64_t num_dirty = 0;
     unsigned long *dest = rb->bmap;

     /* start address and length is aligned at the start of a word? */
     if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
          (start + rb->offset) &&
         !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
         int k;
         int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
         unsigned long * const *src;
         unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
         unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
                                         DIRTY_MEMORY_BLOCK_SIZE);
         unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);

         src = qatomic_rcu_read(
                 &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;

         for (k = page; k < page + nr; k++) {
             if (src[idx][offset]) {
                 unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
                 unsigned long new_dirty;
                 new_dirty = ~dest[k];
                 dest[k] |= bits;
                 new_dirty &= bits;
                 num_dirty += ctpopl(new_dirty);
             }

             if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
                 offset = 0;
                 idx++;
             }
         }

         if (rb->clear_bmap) {
             /*
              * Postpone the dirty bitmap clear to the point before we
              * really send the pages, also we will split the clear
              * dirty procedure into smaller chunks.
              */
             clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
                            length >> TARGET_PAGE_BITS);
         } else {
             /* Slow path - still do that in a huge chunk */
             memory_region_clear_dirty_bitmap(rb->mr, start, length);
         }
     } else {
         ram_addr_t offset = rb->offset;

         for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
             if (cpu_physical_memory_test_and_clear_dirty(
                         start + addr + offset,
                         TARGET_PAGE_SIZE,
                         DIRTY_MEMORY_MIGRATION)) {
                 long k = (start + addr) >> TARGET_PAGE_BITS;
                 if (!test_and_set_bit(k, dest)) {
                     num_dirty++;
                 }
             }
         }
     }

     return num_dirty;
 }
 #endif
 #endif
	/*
	* 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 "cpu.h"
	#include "sysemu/xen.h"
	#include "sysemu/tcg.h"
	#include "exec/ramlist.h"
	#include "exec/ramblock.h"

	extern uint64_t total_dirty_pages;

	/**
	* clear_bmap_size: calculate clear bitmap size
	*
	* @pages: number of guest pages
	* @shift: guest page number shift
	*
	* Returns: number of bits for the clear bitmap
	*/
	static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
	{
	return DIV_ROUND_UP(pages, 1UL << shift);
	}

	/**
	* clear_bmap_set: set clear bitmap for the page range
	*
	* @rb: the ramblock to operate on
	* @start: the start page number
	* @size: number of pages to set in the bitmap
	*
	* Returns: None
	*/
	static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
	uint64_t npages)
	{
	uint8_t shift = rb->clear_bmap_shift;

	bitmap_set_atomic(rb->clear_bmap, start >> shift,
	clear_bmap_size(npages, shift));
	}

	/**
	* clear_bmap_test_and_clear: test clear bitmap for the page, clear if set
	*
	* @rb: the ramblock to operate on
	* @page: the page number to check
	*
	* Returns: true if the bit was set, false otherwise
	*/
	static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
	{
	uint8_t shift = rb->clear_bmap_shift;

	return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1);
	}

	static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
	{
	return (b && b->host && offset < b->used_length) ? true : false;
	}

	static inline void ramblock_ptr(RAMBlock block, ram_addr_t offset)
	{
	assert(offset_in_ramblock(block, offset));
	return (char *)block->host + offset;
	}

	static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
	RAMBlock *rb)
	{
	uint64_t host_addr_offset =
	(uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
	return host_addr_offset >> TARGET_PAGE_BITS;
	}

	bool ramblock_is_pmem(RAMBlock *rb);

	long qemu_minrampagesize(void);
	long qemu_maxrampagesize(void);

	/**
	* qemu_ram_alloc_from_file,
	* qemu_ram_alloc_from_fd: Allocate a ram block from the specified backing
	* file or device
	*
	* Parameters:
	* @size: the size in bytes of the ram block
	* @mr: the memory region where the ram block is
	* @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
	* RAM_NORESERVE.
	* @mem_path or @fd: specify the backing file or device
	* @readonly: true to open @path for reading, false for read/write.
	* @errp: pointer to Error*, to store an error if it happens
	*
	* Return:
	* On success, return a pointer to the ram block.
	* On failure, return NULL.
	*/
	RAMBlock qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion mr,
	uint32_t ram_flags, const char *mem_path,
	bool readonly, Error **errp);
	RAMBlock qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion mr,
	uint32_t ram_flags, int fd, off_t offset,
	bool readonly, Error **errp);

	RAMBlock qemu_ram_alloc_from_ptr(ram_addr_t size, void host,
	MemoryRegion mr, Error *errp);
	RAMBlock qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags, MemoryRegion mr,
	Error **errp);
	RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
	void (resized)(const char,
	uint64_t length,
	void *host),
	MemoryRegion mr, Error *errp);
	void qemu_ram_free(RAMBlock *block);

	int qemu_ram_resize(RAMBlock block, ram_addr_t newsize, Error *errp);

	void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length);

	/* Clear whole block of mem */
	static inline void qemu_ram_block_writeback(RAMBlock *block)
	{
	qemu_ram_msync(block, 0, block->used_length);
	}

	#define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1)
	#define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))

	static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
	ram_addr_t length,
	unsigned client)
	{
	DirtyMemoryBlocks *blocks;
	unsigned long end, page;
	unsigned long idx, offset, base;
	bool dirty = false;

	assert(client < DIRTY_MEMORY_NUM);

	end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
	page = start >> TARGET_PAGE_BITS;

	WITH_RCU_READ_LOCK_GUARD() {
	blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

	idx = page / DIRTY_MEMORY_BLOCK_SIZE;
	offset = page % DIRTY_MEMORY_BLOCK_SIZE;
	base = page - offset;
	while (page < end) {
	unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
	unsigned long num = next - base;
	unsigned long found = find_next_bit(blocks->blocks[idx],
	num, offset);
	if (found < num) {
	dirty = true;
	break;
	}

	page = next;
	idx++;
	offset = 0;
	base += DIRTY_MEMORY_BLOCK_SIZE;
	}
	}

	return dirty;
	}

	static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
	ram_addr_t length,
	unsigned client)
	{
	DirtyMemoryBlocks *blocks;
	unsigned long end, page;
	unsigned long idx, offset, base;
	bool dirty = true;

	assert(client < DIRTY_MEMORY_NUM);

	end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
	page = start >> TARGET_PAGE_BITS;

	RCU_READ_LOCK_GUARD();

	blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

	idx = page / DIRTY_MEMORY_BLOCK_SIZE;
	offset = page % DIRTY_MEMORY_BLOCK_SIZE;
	base = page - offset;
	while (page < end) {
	unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
	unsigned long num = next - base;
	unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
	if (found < num) {
	dirty = false;
	break;
	}

	page = next;
	idx++;
	offset = 0;
	base += DIRTY_MEMORY_BLOCK_SIZE;
	}

	return dirty;
	}

	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 uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
	ram_addr_t length,
	uint8_t mask)
	{
	uint8_t ret = 0;

	if (mask & (1 << DIRTY_MEMORY_VGA) &&
	!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
	ret \|= (1 << DIRTY_MEMORY_VGA);
	}
	if (mask & (1 << DIRTY_MEMORY_CODE) &&
	!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
	ret \|= (1 << DIRTY_MEMORY_CODE);
	}
	if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
	!cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
	ret \|= (1 << DIRTY_MEMORY_MIGRATION);
	}
	return ret;
	}

	static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
	unsigned client)
	{
	unsigned long page, idx, offset;
	DirtyMemoryBlocks *blocks;

	assert(client < DIRTY_MEMORY_NUM);

	page = addr >> TARGET_PAGE_BITS;
	idx = page / DIRTY_MEMORY_BLOCK_SIZE;
	offset = page % DIRTY_MEMORY_BLOCK_SIZE;

	RCU_READ_LOCK_GUARD();

	blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);

	set_bit_atomic(offset, blocks->blocks[idx]);
	}

	static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
	ram_addr_t length,
	uint8_t mask)
	{
	DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
	unsigned long end, page;
	unsigned long idx, offset, base;
	int i;

	if (!mask && !xen_enabled()) {
	return;
	}

	end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
	page = start >> TARGET_PAGE_BITS;

	WITH_RCU_READ_LOCK_GUARD() {
	for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
	blocks[i] = qatomic_rcu_read(&ram_list.dirty_memory[i]);
	}

	idx = page / DIRTY_MEMORY_BLOCK_SIZE;
	offset = page % DIRTY_MEMORY_BLOCK_SIZE;
	base = page - offset;
	while (page < end) {
	unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);

	if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
	bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
	offset, next - page);
	}
	if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
	bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
	offset, next - page);
	}
	if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
	bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
	offset, next - page);
	}

	page = next;
	idx++;
	offset = 0;
	base += DIRTY_MEMORY_BLOCK_SIZE;
	}
	}

	xen_hvm_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 = qemu_real_host_page_size() / 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)) {
	unsigned long **blocks[DIRTY_MEMORY_NUM];
	unsigned long idx;
	unsigned long offset;
	long k;
	long nr = BITS_TO_LONGS(pages);

	idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
	offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
	DIRTY_MEMORY_BLOCK_SIZE);

	WITH_RCU_READ_LOCK_GUARD() {
	for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
	blocks[i] =
	qatomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
	}

	for (k = 0; k < nr; k++) {
	if (bitmap[k]) {
	unsigned long temp = leul_to_cpu(bitmap[k]);

	qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);

	if (global_dirty_tracking) {
	qatomic_or(
	&blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
	temp);
	if (unlikely(
	global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
	total_dirty_pages += ctpopl(temp);
	}
	}

	if (tcg_enabled()) {
	qatomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset],
	temp);
	}
	}

	if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
	offset = 0;
	idx++;
	}
	}
	}

	xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
	} else {
	uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;

	if (!global_dirty_tracking) {
	clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
	}

	/*
	* 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]);
	if (unlikely(global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
	total_dirty_pages += ctpopl(c);
	}
	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, clients);
	} while (c != 0);
	}
	}
	}
	}
	#endif /* not _WIN32 */

	bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
	ram_addr_t length,
	unsigned client);

	DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
	(MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);

	bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
	ram_addr_t start,
	ram_addr_t length);

	static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
	ram_addr_t length)
	{
	cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
	cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
	cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
	}


	/* Called with RCU critical section */
	static inline
	uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
	ram_addr_t start,
	ram_addr_t length)
	{
	ram_addr_t addr;
	unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
	uint64_t num_dirty = 0;
	unsigned long *dest = rb->bmap;

	/* start address and length is aligned at the start of a word? */
	if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
	(start + rb->offset) &&
	!(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
	int k;
	int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
	unsigned long * const *src;
	unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
	unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
	DIRTY_MEMORY_BLOCK_SIZE);
	unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);

	src = qatomic_rcu_read(
	&ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;

	for (k = page; k < page + nr; k++) {
	if (src[idx][offset]) {
	unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
	unsigned long new_dirty;
	new_dirty = ~dest[k];
	dest[k] \|= bits;
	new_dirty &= bits;
	num_dirty += ctpopl(new_dirty);
	}

	if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
	offset = 0;
	idx++;
	}
	}

	if (rb->clear_bmap) {
	/*
	* Postpone the dirty bitmap clear to the point before we
	* really send the pages, also we will split the clear
	* dirty procedure into smaller chunks.
	*/
	clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
	length >> TARGET_PAGE_BITS);
	} else {
	/* Slow path - still do that in a huge chunk */
	memory_region_clear_dirty_bitmap(rb->mr, start, length);
	}
	} else {
	ram_addr_t offset = rb->offset;

	for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
	if (cpu_physical_memory_test_and_clear_dirty(
	start + addr + offset,
	TARGET_PAGE_SIZE,
	DIRTY_MEMORY_MIGRATION)) {
	long k = (start + addr) >> TARGET_PAGE_BITS;
	if (!test_and_set_bit(k, dest)) {
	num_dirty++;
	}
	}
	}
	}

	return num_dirty;
	}
	#endif
	#endif