xref: /openbmc/qemu/include/exec/memory.h (revision 489653b5)
1 /*
2  * Physical memory management API
3  *
4  * Copyright 2011 Red Hat, Inc. and/or its affiliates
5  *
6  * Authors:
7  *  Avi Kivity <avi@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  *
12  */
13 
14 #ifndef MEMORY_H
15 #define MEMORY_H
16 
17 #ifndef CONFIG_USER_ONLY
18 
19 #define DIRTY_MEMORY_VGA       0
20 #define DIRTY_MEMORY_CODE      1
21 #define DIRTY_MEMORY_MIGRATION 2
22 #define DIRTY_MEMORY_NUM       3        /* num of dirty bits */
23 
24 #include <stdint.h>
25 #include <stdbool.h>
26 #include "qemu-common.h"
27 #include "exec/cpu-common.h"
28 #ifndef CONFIG_USER_ONLY
29 #include "exec/hwaddr.h"
30 #endif
31 #include "exec/memattrs.h"
32 #include "qemu/queue.h"
33 #include "qemu/int128.h"
34 #include "qemu/notify.h"
35 #include "qapi/error.h"
36 #include "qom/object.h"
37 #include "qemu/rcu.h"
38 
39 #define MAX_PHYS_ADDR_SPACE_BITS 62
40 #define MAX_PHYS_ADDR            (((hwaddr)1 << MAX_PHYS_ADDR_SPACE_BITS) - 1)
41 
42 #define TYPE_MEMORY_REGION "qemu:memory-region"
43 #define MEMORY_REGION(obj) \
44         OBJECT_CHECK(MemoryRegion, (obj), TYPE_MEMORY_REGION)
45 
46 typedef struct MemoryRegionOps MemoryRegionOps;
47 typedef struct MemoryRegionMmio MemoryRegionMmio;
48 
49 struct MemoryRegionMmio {
50     CPUReadMemoryFunc *read[3];
51     CPUWriteMemoryFunc *write[3];
52 };
53 
54 typedef struct IOMMUTLBEntry IOMMUTLBEntry;
55 
56 /* See address_space_translate: bit 0 is read, bit 1 is write.  */
57 typedef enum {
58     IOMMU_NONE = 0,
59     IOMMU_RO   = 1,
60     IOMMU_WO   = 2,
61     IOMMU_RW   = 3,
62 } IOMMUAccessFlags;
63 
64 struct IOMMUTLBEntry {
65     AddressSpace    *target_as;
66     hwaddr           iova;
67     hwaddr           translated_addr;
68     hwaddr           addr_mask;  /* 0xfff = 4k translation */
69     IOMMUAccessFlags perm;
70 };
71 
72 /* New-style MMIO accessors can indicate that the transaction failed.
73  * A zero (MEMTX_OK) response means success; anything else is a failure
74  * of some kind. The memory subsystem will bitwise-OR together results
75  * if it is synthesizing an operation from multiple smaller accesses.
76  */
77 #define MEMTX_OK 0
78 #define MEMTX_ERROR             (1U << 0) /* device returned an error */
79 #define MEMTX_DECODE_ERROR      (1U << 1) /* nothing at that address */
80 typedef uint32_t MemTxResult;
81 
82 /*
83  * Memory region callbacks
84  */
85 struct MemoryRegionOps {
86     /* Read from the memory region. @addr is relative to @mr; @size is
87      * in bytes. */
88     uint64_t (*read)(void *opaque,
89                      hwaddr addr,
90                      unsigned size);
91     /* Write to the memory region. @addr is relative to @mr; @size is
92      * in bytes. */
93     void (*write)(void *opaque,
94                   hwaddr addr,
95                   uint64_t data,
96                   unsigned size);
97 
98     MemTxResult (*read_with_attrs)(void *opaque,
99                                    hwaddr addr,
100                                    uint64_t *data,
101                                    unsigned size,
102                                    MemTxAttrs attrs);
103     MemTxResult (*write_with_attrs)(void *opaque,
104                                     hwaddr addr,
105                                     uint64_t data,
106                                     unsigned size,
107                                     MemTxAttrs attrs);
108 
109     enum device_endian endianness;
110     /* Guest-visible constraints: */
111     struct {
112         /* If nonzero, specify bounds on access sizes beyond which a machine
113          * check is thrown.
114          */
115         unsigned min_access_size;
116         unsigned max_access_size;
117         /* If true, unaligned accesses are supported.  Otherwise unaligned
118          * accesses throw machine checks.
119          */
120          bool unaligned;
121         /*
122          * If present, and returns #false, the transaction is not accepted
123          * by the device (and results in machine dependent behaviour such
124          * as a machine check exception).
125          */
126         bool (*accepts)(void *opaque, hwaddr addr,
127                         unsigned size, bool is_write);
128     } valid;
129     /* Internal implementation constraints: */
130     struct {
131         /* If nonzero, specifies the minimum size implemented.  Smaller sizes
132          * will be rounded upwards and a partial result will be returned.
133          */
134         unsigned min_access_size;
135         /* If nonzero, specifies the maximum size implemented.  Larger sizes
136          * will be done as a series of accesses with smaller sizes.
137          */
138         unsigned max_access_size;
139         /* If true, unaligned accesses are supported.  Otherwise all accesses
140          * are converted to (possibly multiple) naturally aligned accesses.
141          */
142         bool unaligned;
143     } impl;
144 
145     /* If .read and .write are not present, old_mmio may be used for
146      * backwards compatibility with old mmio registration
147      */
148     const MemoryRegionMmio old_mmio;
149 };
150 
151 typedef struct MemoryRegionIOMMUOps MemoryRegionIOMMUOps;
152 
153 struct MemoryRegionIOMMUOps {
154     /* Return a TLB entry that contains a given address. */
155     IOMMUTLBEntry (*translate)(MemoryRegion *iommu, hwaddr addr, bool is_write);
156 };
157 
158 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
159 typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
160 
161 struct MemoryRegion {
162     Object parent_obj;
163     /* All fields are private - violators will be prosecuted */
164     const MemoryRegionOps *ops;
165     const MemoryRegionIOMMUOps *iommu_ops;
166     void *opaque;
167     MemoryRegion *container;
168     Int128 size;
169     hwaddr addr;
170     void (*destructor)(MemoryRegion *mr);
171     ram_addr_t ram_addr;
172     uint64_t align;
173     bool subpage;
174     bool terminates;
175     bool romd_mode;
176     bool ram;
177     bool skip_dump;
178     bool readonly; /* For RAM regions */
179     bool enabled;
180     bool rom_device;
181     bool warning_printed; /* For reservations */
182     bool flush_coalesced_mmio;
183     MemoryRegion *alias;
184     hwaddr alias_offset;
185     int32_t priority;
186     bool may_overlap;
187     QTAILQ_HEAD(subregions, MemoryRegion) subregions;
188     QTAILQ_ENTRY(MemoryRegion) subregions_link;
189     QTAILQ_HEAD(coalesced_ranges, CoalescedMemoryRange) coalesced;
190     const char *name;
191     uint8_t dirty_log_mask;
192     unsigned ioeventfd_nb;
193     MemoryRegionIoeventfd *ioeventfds;
194     NotifierList iommu_notify;
195 };
196 
197 /**
198  * MemoryListener: callbacks structure for updates to the physical memory map
199  *
200  * Allows a component to adjust to changes in the guest-visible memory map.
201  * Use with memory_listener_register() and memory_listener_unregister().
202  */
203 struct MemoryListener {
204     void (*begin)(MemoryListener *listener);
205     void (*commit)(MemoryListener *listener);
206     void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
207     void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
208     void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
209     void (*log_start)(MemoryListener *listener, MemoryRegionSection *section);
210     void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section);
211     void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);
212     void (*log_global_start)(MemoryListener *listener);
213     void (*log_global_stop)(MemoryListener *listener);
214     void (*eventfd_add)(MemoryListener *listener, MemoryRegionSection *section,
215                         bool match_data, uint64_t data, EventNotifier *e);
216     void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
217                         bool match_data, uint64_t data, EventNotifier *e);
218     void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
219                                hwaddr addr, hwaddr len);
220     void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
221                                hwaddr addr, hwaddr len);
222     /* Lower = earlier (during add), later (during del) */
223     unsigned priority;
224     AddressSpace *address_space_filter;
225     QTAILQ_ENTRY(MemoryListener) link;
226 };
227 
228 /**
229  * AddressSpace: describes a mapping of addresses to #MemoryRegion objects
230  */
231 struct AddressSpace {
232     /* All fields are private. */
233     struct rcu_head rcu;
234     char *name;
235     MemoryRegion *root;
236 
237     /* Accessed via RCU.  */
238     struct FlatView *current_map;
239 
240     int ioeventfd_nb;
241     struct MemoryRegionIoeventfd *ioeventfds;
242     struct AddressSpaceDispatch *dispatch;
243     struct AddressSpaceDispatch *next_dispatch;
244     MemoryListener dispatch_listener;
245 
246     QTAILQ_ENTRY(AddressSpace) address_spaces_link;
247 };
248 
249 /**
250  * MemoryRegionSection: describes a fragment of a #MemoryRegion
251  *
252  * @mr: the region, or %NULL if empty
253  * @address_space: the address space the region is mapped in
254  * @offset_within_region: the beginning of the section, relative to @mr's start
255  * @size: the size of the section; will not exceed @mr's boundaries
256  * @offset_within_address_space: the address of the first byte of the section
257  *     relative to the region's address space
258  * @readonly: writes to this section are ignored
259  */
260 struct MemoryRegionSection {
261     MemoryRegion *mr;
262     AddressSpace *address_space;
263     hwaddr offset_within_region;
264     Int128 size;
265     hwaddr offset_within_address_space;
266     bool readonly;
267 };
268 
269 /**
270  * memory_region_init: Initialize a memory region
271  *
272  * The region typically acts as a container for other memory regions.  Use
273  * memory_region_add_subregion() to add subregions.
274  *
275  * @mr: the #MemoryRegion to be initialized
276  * @owner: the object that tracks the region's reference count
277  * @name: used for debugging; not visible to the user or ABI
278  * @size: size of the region; any subregions beyond this size will be clipped
279  */
280 void memory_region_init(MemoryRegion *mr,
281                         struct Object *owner,
282                         const char *name,
283                         uint64_t size);
284 
285 /**
286  * memory_region_ref: Add 1 to a memory region's reference count
287  *
288  * Whenever memory regions are accessed outside the BQL, they need to be
289  * preserved against hot-unplug.  MemoryRegions actually do not have their
290  * own reference count; they piggyback on a QOM object, their "owner".
291  * This function adds a reference to the owner.
292  *
293  * All MemoryRegions must have an owner if they can disappear, even if the
294  * device they belong to operates exclusively under the BQL.  This is because
295  * the region could be returned at any time by memory_region_find, and this
296  * is usually under guest control.
297  *
298  * @mr: the #MemoryRegion
299  */
300 void memory_region_ref(MemoryRegion *mr);
301 
302 /**
303  * memory_region_unref: Remove 1 to a memory region's reference count
304  *
305  * Whenever memory regions are accessed outside the BQL, they need to be
306  * preserved against hot-unplug.  MemoryRegions actually do not have their
307  * own reference count; they piggyback on a QOM object, their "owner".
308  * This function removes a reference to the owner and possibly destroys it.
309  *
310  * @mr: the #MemoryRegion
311  */
312 void memory_region_unref(MemoryRegion *mr);
313 
314 /**
315  * memory_region_init_io: Initialize an I/O memory region.
316  *
317  * Accesses into the region will cause the callbacks in @ops to be called.
318  * if @size is nonzero, subregions will be clipped to @size.
319  *
320  * @mr: the #MemoryRegion to be initialized.
321  * @owner: the object that tracks the region's reference count
322  * @ops: a structure containing read and write callbacks to be used when
323  *       I/O is performed on the region.
324  * @opaque: passed to to the read and write callbacks of the @ops structure.
325  * @name: used for debugging; not visible to the user or ABI
326  * @size: size of the region.
327  */
328 void memory_region_init_io(MemoryRegion *mr,
329                            struct Object *owner,
330                            const MemoryRegionOps *ops,
331                            void *opaque,
332                            const char *name,
333                            uint64_t size);
334 
335 /**
336  * memory_region_init_ram:  Initialize RAM memory region.  Accesses into the
337  *                          region will modify memory directly.
338  *
339  * @mr: the #MemoryRegion to be initialized.
340  * @owner: the object that tracks the region's reference count
341  * @name: the name of the region.
342  * @size: size of the region.
343  * @errp: pointer to Error*, to store an error if it happens.
344  */
345 void memory_region_init_ram(MemoryRegion *mr,
346                             struct Object *owner,
347                             const char *name,
348                             uint64_t size,
349                             Error **errp);
350 
351 /**
352  * memory_region_init_resizeable_ram:  Initialize memory region with resizeable
353  *                                     RAM.  Accesses into the region will
354  *                                     modify memory directly.  Only an initial
355  *                                     portion of this RAM is actually used.
356  *                                     The used size can change across reboots.
357  *
358  * @mr: the #MemoryRegion to be initialized.
359  * @owner: the object that tracks the region's reference count
360  * @name: the name of the region.
361  * @size: used size of the region.
362  * @max_size: max size of the region.
363  * @resized: callback to notify owner about used size change.
364  * @errp: pointer to Error*, to store an error if it happens.
365  */
366 void memory_region_init_resizeable_ram(MemoryRegion *mr,
367                                        struct Object *owner,
368                                        const char *name,
369                                        uint64_t size,
370                                        uint64_t max_size,
371                                        void (*resized)(const char*,
372                                                        uint64_t length,
373                                                        void *host),
374                                        Error **errp);
375 #ifdef __linux__
376 /**
377  * memory_region_init_ram_from_file:  Initialize RAM memory region with a
378  *                                    mmap-ed backend.
379  *
380  * @mr: the #MemoryRegion to be initialized.
381  * @owner: the object that tracks the region's reference count
382  * @name: the name of the region.
383  * @size: size of the region.
384  * @share: %true if memory must be mmaped with the MAP_SHARED flag
385  * @path: the path in which to allocate the RAM.
386  * @errp: pointer to Error*, to store an error if it happens.
387  */
388 void memory_region_init_ram_from_file(MemoryRegion *mr,
389                                       struct Object *owner,
390                                       const char *name,
391                                       uint64_t size,
392                                       bool share,
393                                       const char *path,
394                                       Error **errp);
395 #endif
396 
397 /**
398  * memory_region_init_ram_ptr:  Initialize RAM memory region from a
399  *                              user-provided pointer.  Accesses into the
400  *                              region will modify memory directly.
401  *
402  * @mr: the #MemoryRegion to be initialized.
403  * @owner: the object that tracks the region's reference count
404  * @name: the name of the region.
405  * @size: size of the region.
406  * @ptr: memory to be mapped; must contain at least @size bytes.
407  */
408 void memory_region_init_ram_ptr(MemoryRegion *mr,
409                                 struct Object *owner,
410                                 const char *name,
411                                 uint64_t size,
412                                 void *ptr);
413 
414 /**
415  * memory_region_init_alias: Initialize a memory region that aliases all or a
416  *                           part of another memory region.
417  *
418  * @mr: the #MemoryRegion to be initialized.
419  * @owner: the object that tracks the region's reference count
420  * @name: used for debugging; not visible to the user or ABI
421  * @orig: the region to be referenced; @mr will be equivalent to
422  *        @orig between @offset and @offset + @size - 1.
423  * @offset: start of the section in @orig to be referenced.
424  * @size: size of the region.
425  */
426 void memory_region_init_alias(MemoryRegion *mr,
427                               struct Object *owner,
428                               const char *name,
429                               MemoryRegion *orig,
430                               hwaddr offset,
431                               uint64_t size);
432 
433 /**
434  * memory_region_init_rom_device:  Initialize a ROM memory region.  Writes are
435  *                                 handled via callbacks.
436  *
437  * @mr: the #MemoryRegion to be initialized.
438  * @owner: the object that tracks the region's reference count
439  * @ops: callbacks for write access handling.
440  * @name: the name of the region.
441  * @size: size of the region.
442  * @errp: pointer to Error*, to store an error if it happens.
443  */
444 void memory_region_init_rom_device(MemoryRegion *mr,
445                                    struct Object *owner,
446                                    const MemoryRegionOps *ops,
447                                    void *opaque,
448                                    const char *name,
449                                    uint64_t size,
450                                    Error **errp);
451 
452 /**
453  * memory_region_init_reservation: Initialize a memory region that reserves
454  *                                 I/O space.
455  *
456  * A reservation region primariy serves debugging purposes.  It claims I/O
457  * space that is not supposed to be handled by QEMU itself.  Any access via
458  * the memory API will cause an abort().
459  *
460  * @mr: the #MemoryRegion to be initialized
461  * @owner: the object that tracks the region's reference count
462  * @name: used for debugging; not visible to the user or ABI
463  * @size: size of the region.
464  */
465 void memory_region_init_reservation(MemoryRegion *mr,
466                                     struct Object *owner,
467                                     const char *name,
468                                     uint64_t size);
469 
470 /**
471  * memory_region_init_iommu: Initialize a memory region that translates
472  * addresses
473  *
474  * An IOMMU region translates addresses and forwards accesses to a target
475  * memory region.
476  *
477  * @mr: the #MemoryRegion to be initialized
478  * @owner: the object that tracks the region's reference count
479  * @ops: a function that translates addresses into the @target region
480  * @name: used for debugging; not visible to the user or ABI
481  * @size: size of the region.
482  */
483 void memory_region_init_iommu(MemoryRegion *mr,
484                               struct Object *owner,
485                               const MemoryRegionIOMMUOps *ops,
486                               const char *name,
487                               uint64_t size);
488 
489 /**
490  * memory_region_owner: get a memory region's owner.
491  *
492  * @mr: the memory region being queried.
493  */
494 struct Object *memory_region_owner(MemoryRegion *mr);
495 
496 /**
497  * memory_region_size: get a memory region's size.
498  *
499  * @mr: the memory region being queried.
500  */
501 uint64_t memory_region_size(MemoryRegion *mr);
502 
503 /**
504  * memory_region_is_ram: check whether a memory region is random access
505  *
506  * Returns %true is a memory region is random access.
507  *
508  * @mr: the memory region being queried
509  */
510 bool memory_region_is_ram(MemoryRegion *mr);
511 
512 /**
513  * memory_region_is_skip_dump: check whether a memory region should not be
514  *                             dumped
515  *
516  * Returns %true is a memory region should not be dumped(e.g. VFIO BAR MMAP).
517  *
518  * @mr: the memory region being queried
519  */
520 bool memory_region_is_skip_dump(MemoryRegion *mr);
521 
522 /**
523  * memory_region_set_skip_dump: Set skip_dump flag, dump will ignore this memory
524  *                              region
525  *
526  * @mr: the memory region being queried
527  */
528 void memory_region_set_skip_dump(MemoryRegion *mr);
529 
530 /**
531  * memory_region_is_romd: check whether a memory region is in ROMD mode
532  *
533  * Returns %true if a memory region is a ROM device and currently set to allow
534  * direct reads.
535  *
536  * @mr: the memory region being queried
537  */
538 static inline bool memory_region_is_romd(MemoryRegion *mr)
539 {
540     return mr->rom_device && mr->romd_mode;
541 }
542 
543 /**
544  * memory_region_is_iommu: check whether a memory region is an iommu
545  *
546  * Returns %true is a memory region is an iommu.
547  *
548  * @mr: the memory region being queried
549  */
550 bool memory_region_is_iommu(MemoryRegion *mr);
551 
552 /**
553  * memory_region_notify_iommu: notify a change in an IOMMU translation entry.
554  *
555  * @mr: the memory region that was changed
556  * @entry: the new entry in the IOMMU translation table.  The entry
557  *         replaces all old entries for the same virtual I/O address range.
558  *         Deleted entries have .@perm == 0.
559  */
560 void memory_region_notify_iommu(MemoryRegion *mr,
561                                 IOMMUTLBEntry entry);
562 
563 /**
564  * memory_region_register_iommu_notifier: register a notifier for changes to
565  * IOMMU translation entries.
566  *
567  * @mr: the memory region to observe
568  * @n: the notifier to be added; the notifier receives a pointer to an
569  *     #IOMMUTLBEntry as the opaque value; the pointer ceases to be
570  *     valid on exit from the notifier.
571  */
572 void memory_region_register_iommu_notifier(MemoryRegion *mr, Notifier *n);
573 
574 /**
575  * memory_region_unregister_iommu_notifier: unregister a notifier for
576  * changes to IOMMU translation entries.
577  *
578  * @n: the notifier to be removed.
579  */
580 void memory_region_unregister_iommu_notifier(Notifier *n);
581 
582 /**
583  * memory_region_name: get a memory region's name
584  *
585  * Returns the string that was used to initialize the memory region.
586  *
587  * @mr: the memory region being queried
588  */
589 const char *memory_region_name(const MemoryRegion *mr);
590 
591 /**
592  * memory_region_is_logging: return whether a memory region is logging writes
593  *
594  * Returns %true if the memory region is logging writes
595  *
596  * @mr: the memory region being queried
597  */
598 bool memory_region_is_logging(MemoryRegion *mr);
599 
600 /**
601  * memory_region_is_rom: check whether a memory region is ROM
602  *
603  * Returns %true is a memory region is read-only memory.
604  *
605  * @mr: the memory region being queried
606  */
607 bool memory_region_is_rom(MemoryRegion *mr);
608 
609 /**
610  * memory_region_get_fd: Get a file descriptor backing a RAM memory region.
611  *
612  * Returns a file descriptor backing a file-based RAM memory region,
613  * or -1 if the region is not a file-based RAM memory region.
614  *
615  * @mr: the RAM or alias memory region being queried.
616  */
617 int memory_region_get_fd(MemoryRegion *mr);
618 
619 /**
620  * memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
621  *
622  * Returns a host pointer to a RAM memory region (created with
623  * memory_region_init_ram() or memory_region_init_ram_ptr()).  Use with
624  * care.
625  *
626  * @mr: the memory region being queried.
627  */
628 void *memory_region_get_ram_ptr(MemoryRegion *mr);
629 
630 /* memory_region_ram_resize: Resize a RAM region.
631  *
632  * Only legal before guest might have detected the memory size: e.g. on
633  * incoming migration, or right after reset.
634  *
635  * @mr: a memory region created with @memory_region_init_resizeable_ram.
636  * @newsize: the new size the region
637  * @errp: pointer to Error*, to store an error if it happens.
638  */
639 void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize,
640                               Error **errp);
641 
642 /**
643  * memory_region_set_log: Turn dirty logging on or off for a region.
644  *
645  * Turns dirty logging on or off for a specified client (display, migration).
646  * Only meaningful for RAM regions.
647  *
648  * @mr: the memory region being updated.
649  * @log: whether dirty logging is to be enabled or disabled.
650  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
651  *          %DIRTY_MEMORY_VGA.
652  */
653 void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);
654 
655 /**
656  * memory_region_get_dirty: Check whether a range of bytes is dirty
657  *                          for a specified client.
658  *
659  * Checks whether a range of bytes has been written to since the last
660  * call to memory_region_reset_dirty() with the same @client.  Dirty logging
661  * must be enabled.
662  *
663  * @mr: the memory region being queried.
664  * @addr: the address (relative to the start of the region) being queried.
665  * @size: the size of the range being queried.
666  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
667  *          %DIRTY_MEMORY_VGA.
668  */
669 bool memory_region_get_dirty(MemoryRegion *mr, hwaddr addr,
670                              hwaddr size, unsigned client);
671 
672 /**
673  * memory_region_set_dirty: Mark a range of bytes as dirty in a memory region.
674  *
675  * Marks a range of bytes as dirty, after it has been dirtied outside
676  * guest code.
677  *
678  * @mr: the memory region being dirtied.
679  * @addr: the address (relative to the start of the region) being dirtied.
680  * @size: size of the range being dirtied.
681  */
682 void memory_region_set_dirty(MemoryRegion *mr, hwaddr addr,
683                              hwaddr size);
684 
685 /**
686  * memory_region_test_and_clear_dirty: Check whether a range of bytes is dirty
687  *                                     for a specified client. It clears them.
688  *
689  * Checks whether a range of bytes has been written to since the last
690  * call to memory_region_reset_dirty() with the same @client.  Dirty logging
691  * must be enabled.
692  *
693  * @mr: the memory region being queried.
694  * @addr: the address (relative to the start of the region) being queried.
695  * @size: the size of the range being queried.
696  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
697  *          %DIRTY_MEMORY_VGA.
698  */
699 bool memory_region_test_and_clear_dirty(MemoryRegion *mr, hwaddr addr,
700                                         hwaddr size, unsigned client);
701 /**
702  * memory_region_sync_dirty_bitmap: Synchronize a region's dirty bitmap with
703  *                                  any external TLBs (e.g. kvm)
704  *
705  * Flushes dirty information from accelerators such as kvm and vhost-net
706  * and makes it available to users of the memory API.
707  *
708  * @mr: the region being flushed.
709  */
710 void memory_region_sync_dirty_bitmap(MemoryRegion *mr);
711 
712 /**
713  * memory_region_reset_dirty: Mark a range of pages as clean, for a specified
714  *                            client.
715  *
716  * Marks a range of pages as no longer dirty.
717  *
718  * @mr: the region being updated.
719  * @addr: the start of the subrange being cleaned.
720  * @size: the size of the subrange being cleaned.
721  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
722  *          %DIRTY_MEMORY_VGA.
723  */
724 void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
725                                hwaddr size, unsigned client);
726 
727 /**
728  * memory_region_set_readonly: Turn a memory region read-only (or read-write)
729  *
730  * Allows a memory region to be marked as read-only (turning it into a ROM).
731  * only useful on RAM regions.
732  *
733  * @mr: the region being updated.
734  * @readonly: whether rhe region is to be ROM or RAM.
735  */
736 void memory_region_set_readonly(MemoryRegion *mr, bool readonly);
737 
738 /**
739  * memory_region_rom_device_set_romd: enable/disable ROMD mode
740  *
741  * Allows a ROM device (initialized with memory_region_init_rom_device() to
742  * set to ROMD mode (default) or MMIO mode.  When it is in ROMD mode, the
743  * device is mapped to guest memory and satisfies read access directly.
744  * When in MMIO mode, reads are forwarded to the #MemoryRegion.read function.
745  * Writes are always handled by the #MemoryRegion.write function.
746  *
747  * @mr: the memory region to be updated
748  * @romd_mode: %true to put the region into ROMD mode
749  */
750 void memory_region_rom_device_set_romd(MemoryRegion *mr, bool romd_mode);
751 
752 /**
753  * memory_region_set_coalescing: Enable memory coalescing for the region.
754  *
755  * Enabled writes to a region to be queued for later processing. MMIO ->write
756  * callbacks may be delayed until a non-coalesced MMIO is issued.
757  * Only useful for IO regions.  Roughly similar to write-combining hardware.
758  *
759  * @mr: the memory region to be write coalesced
760  */
761 void memory_region_set_coalescing(MemoryRegion *mr);
762 
763 /**
764  * memory_region_add_coalescing: Enable memory coalescing for a sub-range of
765  *                               a region.
766  *
767  * Like memory_region_set_coalescing(), but works on a sub-range of a region.
768  * Multiple calls can be issued coalesced disjoint ranges.
769  *
770  * @mr: the memory region to be updated.
771  * @offset: the start of the range within the region to be coalesced.
772  * @size: the size of the subrange to be coalesced.
773  */
774 void memory_region_add_coalescing(MemoryRegion *mr,
775                                   hwaddr offset,
776                                   uint64_t size);
777 
778 /**
779  * memory_region_clear_coalescing: Disable MMIO coalescing for the region.
780  *
781  * Disables any coalescing caused by memory_region_set_coalescing() or
782  * memory_region_add_coalescing().  Roughly equivalent to uncacheble memory
783  * hardware.
784  *
785  * @mr: the memory region to be updated.
786  */
787 void memory_region_clear_coalescing(MemoryRegion *mr);
788 
789 /**
790  * memory_region_set_flush_coalesced: Enforce memory coalescing flush before
791  *                                    accesses.
792  *
793  * Ensure that pending coalesced MMIO request are flushed before the memory
794  * region is accessed. This property is automatically enabled for all regions
795  * passed to memory_region_set_coalescing() and memory_region_add_coalescing().
796  *
797  * @mr: the memory region to be updated.
798  */
799 void memory_region_set_flush_coalesced(MemoryRegion *mr);
800 
801 /**
802  * memory_region_clear_flush_coalesced: Disable memory coalescing flush before
803  *                                      accesses.
804  *
805  * Clear the automatic coalesced MMIO flushing enabled via
806  * memory_region_set_flush_coalesced. Note that this service has no effect on
807  * memory regions that have MMIO coalescing enabled for themselves. For them,
808  * automatic flushing will stop once coalescing is disabled.
809  *
810  * @mr: the memory region to be updated.
811  */
812 void memory_region_clear_flush_coalesced(MemoryRegion *mr);
813 
814 /**
815  * memory_region_add_eventfd: Request an eventfd to be triggered when a word
816  *                            is written to a location.
817  *
818  * Marks a word in an IO region (initialized with memory_region_init_io())
819  * as a trigger for an eventfd event.  The I/O callback will not be called.
820  * The caller must be prepared to handle failure (that is, take the required
821  * action if the callback _is_ called).
822  *
823  * @mr: the memory region being updated.
824  * @addr: the address within @mr that is to be monitored
825  * @size: the size of the access to trigger the eventfd
826  * @match_data: whether to match against @data, instead of just @addr
827  * @data: the data to match against the guest write
828  * @fd: the eventfd to be triggered when @addr, @size, and @data all match.
829  **/
830 void memory_region_add_eventfd(MemoryRegion *mr,
831                                hwaddr addr,
832                                unsigned size,
833                                bool match_data,
834                                uint64_t data,
835                                EventNotifier *e);
836 
837 /**
838  * memory_region_del_eventfd: Cancel an eventfd.
839  *
840  * Cancels an eventfd trigger requested by a previous
841  * memory_region_add_eventfd() call.
842  *
843  * @mr: the memory region being updated.
844  * @addr: the address within @mr that is to be monitored
845  * @size: the size of the access to trigger the eventfd
846  * @match_data: whether to match against @data, instead of just @addr
847  * @data: the data to match against the guest write
848  * @fd: the eventfd to be triggered when @addr, @size, and @data all match.
849  */
850 void memory_region_del_eventfd(MemoryRegion *mr,
851                                hwaddr addr,
852                                unsigned size,
853                                bool match_data,
854                                uint64_t data,
855                                EventNotifier *e);
856 
857 /**
858  * memory_region_add_subregion: Add a subregion to a container.
859  *
860  * Adds a subregion at @offset.  The subregion may not overlap with other
861  * subregions (except for those explicitly marked as overlapping).  A region
862  * may only be added once as a subregion (unless removed with
863  * memory_region_del_subregion()); use memory_region_init_alias() if you
864  * want a region to be a subregion in multiple locations.
865  *
866  * @mr: the region to contain the new subregion; must be a container
867  *      initialized with memory_region_init().
868  * @offset: the offset relative to @mr where @subregion is added.
869  * @subregion: the subregion to be added.
870  */
871 void memory_region_add_subregion(MemoryRegion *mr,
872                                  hwaddr offset,
873                                  MemoryRegion *subregion);
874 /**
875  * memory_region_add_subregion_overlap: Add a subregion to a container
876  *                                      with overlap.
877  *
878  * Adds a subregion at @offset.  The subregion may overlap with other
879  * subregions.  Conflicts are resolved by having a higher @priority hide a
880  * lower @priority. Subregions without priority are taken as @priority 0.
881  * A region may only be added once as a subregion (unless removed with
882  * memory_region_del_subregion()); use memory_region_init_alias() if you
883  * want a region to be a subregion in multiple locations.
884  *
885  * @mr: the region to contain the new subregion; must be a container
886  *      initialized with memory_region_init().
887  * @offset: the offset relative to @mr where @subregion is added.
888  * @subregion: the subregion to be added.
889  * @priority: used for resolving overlaps; highest priority wins.
890  */
891 void memory_region_add_subregion_overlap(MemoryRegion *mr,
892                                          hwaddr offset,
893                                          MemoryRegion *subregion,
894                                          int priority);
895 
896 /**
897  * memory_region_get_ram_addr: Get the ram address associated with a memory
898  *                             region
899  *
900  * DO NOT USE THIS FUNCTION.  This is a temporary workaround while the Xen
901  * code is being reworked.
902  */
903 ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr);
904 
905 uint64_t memory_region_get_alignment(const MemoryRegion *mr);
906 /**
907  * memory_region_del_subregion: Remove a subregion.
908  *
909  * Removes a subregion from its container.
910  *
911  * @mr: the container to be updated.
912  * @subregion: the region being removed; must be a current subregion of @mr.
913  */
914 void memory_region_del_subregion(MemoryRegion *mr,
915                                  MemoryRegion *subregion);
916 
917 /*
918  * memory_region_set_enabled: dynamically enable or disable a region
919  *
920  * Enables or disables a memory region.  A disabled memory region
921  * ignores all accesses to itself and its subregions.  It does not
922  * obscure sibling subregions with lower priority - it simply behaves as
923  * if it was removed from the hierarchy.
924  *
925  * Regions default to being enabled.
926  *
927  * @mr: the region to be updated
928  * @enabled: whether to enable or disable the region
929  */
930 void memory_region_set_enabled(MemoryRegion *mr, bool enabled);
931 
932 /*
933  * memory_region_set_address: dynamically update the address of a region
934  *
935  * Dynamically updates the address of a region, relative to its container.
936  * May be used on regions are currently part of a memory hierarchy.
937  *
938  * @mr: the region to be updated
939  * @addr: new address, relative to container region
940  */
941 void memory_region_set_address(MemoryRegion *mr, hwaddr addr);
942 
943 /*
944  * memory_region_set_size: dynamically update the size of a region.
945  *
946  * Dynamically updates the size of a region.
947  *
948  * @mr: the region to be updated
949  * @size: used size of the region.
950  */
951 void memory_region_set_size(MemoryRegion *mr, uint64_t size);
952 
953 /*
954  * memory_region_set_alias_offset: dynamically update a memory alias's offset
955  *
956  * Dynamically updates the offset into the target region that an alias points
957  * to, as if the fourth argument to memory_region_init_alias() has changed.
958  *
959  * @mr: the #MemoryRegion to be updated; should be an alias.
960  * @offset: the new offset into the target memory region
961  */
962 void memory_region_set_alias_offset(MemoryRegion *mr,
963                                     hwaddr offset);
964 
965 /**
966  * memory_region_present: checks if an address relative to a @container
967  * translates into #MemoryRegion within @container
968  *
969  * Answer whether a #MemoryRegion within @container covers the address
970  * @addr.
971  *
972  * @container: a #MemoryRegion within which @addr is a relative address
973  * @addr: the area within @container to be searched
974  */
975 bool memory_region_present(MemoryRegion *container, hwaddr addr);
976 
977 /**
978  * memory_region_is_mapped: returns true if #MemoryRegion is mapped
979  * into any address space.
980  *
981  * @mr: a #MemoryRegion which should be checked if it's mapped
982  */
983 bool memory_region_is_mapped(MemoryRegion *mr);
984 
985 /**
986  * memory_region_find: translate an address/size relative to a
987  * MemoryRegion into a #MemoryRegionSection.
988  *
989  * Locates the first #MemoryRegion within @mr that overlaps the range
990  * given by @addr and @size.
991  *
992  * Returns a #MemoryRegionSection that describes a contiguous overlap.
993  * It will have the following characteristics:
994  *    .@size = 0 iff no overlap was found
995  *    .@mr is non-%NULL iff an overlap was found
996  *
997  * Remember that in the return value the @offset_within_region is
998  * relative to the returned region (in the .@mr field), not to the
999  * @mr argument.
1000  *
1001  * Similarly, the .@offset_within_address_space is relative to the
1002  * address space that contains both regions, the passed and the
1003  * returned one.  However, in the special case where the @mr argument
1004  * has no container (and thus is the root of the address space), the
1005  * following will hold:
1006  *    .@offset_within_address_space >= @addr
1007  *    .@offset_within_address_space + .@size <= @addr + @size
1008  *
1009  * @mr: a MemoryRegion within which @addr is a relative address
1010  * @addr: start of the area within @as to be searched
1011  * @size: size of the area to be searched
1012  */
1013 MemoryRegionSection memory_region_find(MemoryRegion *mr,
1014                                        hwaddr addr, uint64_t size);
1015 
1016 /**
1017  * address_space_sync_dirty_bitmap: synchronize the dirty log for all memory
1018  *
1019  * Synchronizes the dirty page log for an entire address space.
1020  * @as: the address space that contains the memory being synchronized
1021  */
1022 void address_space_sync_dirty_bitmap(AddressSpace *as);
1023 
1024 /**
1025  * memory_region_transaction_begin: Start a transaction.
1026  *
1027  * During a transaction, changes will be accumulated and made visible
1028  * only when the transaction ends (is committed).
1029  */
1030 void memory_region_transaction_begin(void);
1031 
1032 /**
1033  * memory_region_transaction_commit: Commit a transaction and make changes
1034  *                                   visible to the guest.
1035  */
1036 void memory_region_transaction_commit(void);
1037 
1038 /**
1039  * memory_listener_register: register callbacks to be called when memory
1040  *                           sections are mapped or unmapped into an address
1041  *                           space
1042  *
1043  * @listener: an object containing the callbacks to be called
1044  * @filter: if non-%NULL, only regions in this address space will be observed
1045  */
1046 void memory_listener_register(MemoryListener *listener, AddressSpace *filter);
1047 
1048 /**
1049  * memory_listener_unregister: undo the effect of memory_listener_register()
1050  *
1051  * @listener: an object containing the callbacks to be removed
1052  */
1053 void memory_listener_unregister(MemoryListener *listener);
1054 
1055 /**
1056  * memory_global_dirty_log_start: begin dirty logging for all regions
1057  */
1058 void memory_global_dirty_log_start(void);
1059 
1060 /**
1061  * memory_global_dirty_log_stop: end dirty logging for all regions
1062  */
1063 void memory_global_dirty_log_stop(void);
1064 
1065 void mtree_info(fprintf_function mon_printf, void *f);
1066 
1067 /**
1068  * memory_region_dispatch_read: perform a read directly to the specified
1069  * MemoryRegion.
1070  *
1071  * @mr: #MemoryRegion to access
1072  * @addr: address within that region
1073  * @pval: pointer to uint64_t which the data is written to
1074  * @size: size of the access in bytes
1075  * @attrs: memory transaction attributes to use for the access
1076  */
1077 MemTxResult memory_region_dispatch_read(MemoryRegion *mr,
1078                                         hwaddr addr,
1079                                         uint64_t *pval,
1080                                         unsigned size,
1081                                         MemTxAttrs attrs);
1082 /**
1083  * memory_region_dispatch_write: perform a write directly to the specified
1084  * MemoryRegion.
1085  *
1086  * @mr: #MemoryRegion to access
1087  * @addr: address within that region
1088  * @data: data to write
1089  * @size: size of the access in bytes
1090  * @attrs: memory transaction attributes to use for the access
1091  */
1092 MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
1093                                          hwaddr addr,
1094                                          uint64_t data,
1095                                          unsigned size,
1096                                          MemTxAttrs attrs);
1097 
1098 /**
1099  * address_space_init: initializes an address space
1100  *
1101  * @as: an uninitialized #AddressSpace
1102  * @root: a #MemoryRegion that routes addesses for the address space
1103  * @name: an address space name.  The name is only used for debugging
1104  *        output.
1105  */
1106 void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name);
1107 
1108 
1109 /**
1110  * address_space_destroy: destroy an address space
1111  *
1112  * Releases all resources associated with an address space.  After an address space
1113  * is destroyed, its root memory region (given by address_space_init()) may be destroyed
1114  * as well.
1115  *
1116  * @as: address space to be destroyed
1117  */
1118 void address_space_destroy(AddressSpace *as);
1119 
1120 /**
1121  * address_space_rw: read from or write to an address space.
1122  *
1123  * Return a MemTxResult indicating whether the operation succeeded
1124  * or failed (eg unassigned memory, device rejected the transaction,
1125  * IOMMU fault).
1126  *
1127  * @as: #AddressSpace to be accessed
1128  * @addr: address within that address space
1129  * @attrs: memory transaction attributes
1130  * @buf: buffer with the data transferred
1131  * @is_write: indicates the transfer direction
1132  */
1133 MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
1134                              MemTxAttrs attrs, uint8_t *buf,
1135                              int len, bool is_write);
1136 
1137 /**
1138  * address_space_write: write to address space.
1139  *
1140  * Return a MemTxResult indicating whether the operation succeeded
1141  * or failed (eg unassigned memory, device rejected the transaction,
1142  * IOMMU fault).
1143  *
1144  * @as: #AddressSpace to be accessed
1145  * @addr: address within that address space
1146  * @attrs: memory transaction attributes
1147  * @buf: buffer with the data transferred
1148  */
1149 MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
1150                                 MemTxAttrs attrs,
1151                                 const uint8_t *buf, int len);
1152 
1153 /**
1154  * address_space_read: read from an address space.
1155  *
1156  * Return a MemTxResult indicating whether the operation succeeded
1157  * or failed (eg unassigned memory, device rejected the transaction,
1158  * IOMMU fault).
1159  *
1160  * @as: #AddressSpace to be accessed
1161  * @addr: address within that address space
1162  * @attrs: memory transaction attributes
1163  * @buf: buffer with the data transferred
1164  */
1165 MemTxResult address_space_read(AddressSpace *as, hwaddr addr, MemTxAttrs attrs,
1166                                uint8_t *buf, int len);
1167 
1168 /**
1169  * address_space_ld*: load from an address space
1170  * address_space_st*: store to an address space
1171  *
1172  * These functions perform a load or store of the byte, word,
1173  * longword or quad to the specified address within the AddressSpace.
1174  * The _le suffixed functions treat the data as little endian;
1175  * _be indicates big endian; no suffix indicates "same endianness
1176  * as guest CPU".
1177  *
1178  * The "guest CPU endianness" accessors are deprecated for use outside
1179  * target-* code; devices should be CPU-agnostic and use either the LE
1180  * or the BE accessors.
1181  *
1182  * @as #AddressSpace to be accessed
1183  * @addr: address within that address space
1184  * @val: data value, for stores
1185  * @attrs: memory transaction attributes
1186  * @result: location to write the success/failure of the transaction;
1187  *   if NULL, this information is discarded
1188  */
1189 uint32_t address_space_ldub(AddressSpace *as, hwaddr addr,
1190                             MemTxAttrs attrs, MemTxResult *result);
1191 uint32_t address_space_lduw_le(AddressSpace *as, hwaddr addr,
1192                             MemTxAttrs attrs, MemTxResult *result);
1193 uint32_t address_space_lduw_be(AddressSpace *as, hwaddr addr,
1194                             MemTxAttrs attrs, MemTxResult *result);
1195 uint32_t address_space_ldl_le(AddressSpace *as, hwaddr addr,
1196                             MemTxAttrs attrs, MemTxResult *result);
1197 uint32_t address_space_ldl_be(AddressSpace *as, hwaddr addr,
1198                             MemTxAttrs attrs, MemTxResult *result);
1199 uint64_t address_space_ldq_le(AddressSpace *as, hwaddr addr,
1200                             MemTxAttrs attrs, MemTxResult *result);
1201 uint64_t address_space_ldq_be(AddressSpace *as, hwaddr addr,
1202                             MemTxAttrs attrs, MemTxResult *result);
1203 void address_space_stb(AddressSpace *as, hwaddr addr, uint32_t val,
1204                             MemTxAttrs attrs, MemTxResult *result);
1205 void address_space_stw_le(AddressSpace *as, hwaddr addr, uint32_t val,
1206                             MemTxAttrs attrs, MemTxResult *result);
1207 void address_space_stw_be(AddressSpace *as, hwaddr addr, uint32_t val,
1208                             MemTxAttrs attrs, MemTxResult *result);
1209 void address_space_stl_le(AddressSpace *as, hwaddr addr, uint32_t val,
1210                             MemTxAttrs attrs, MemTxResult *result);
1211 void address_space_stl_be(AddressSpace *as, hwaddr addr, uint32_t val,
1212                             MemTxAttrs attrs, MemTxResult *result);
1213 void address_space_stq_le(AddressSpace *as, hwaddr addr, uint64_t val,
1214                             MemTxAttrs attrs, MemTxResult *result);
1215 void address_space_stq_be(AddressSpace *as, hwaddr addr, uint64_t val,
1216                             MemTxAttrs attrs, MemTxResult *result);
1217 
1218 #ifdef NEED_CPU_H
1219 uint32_t address_space_lduw(AddressSpace *as, hwaddr addr,
1220                             MemTxAttrs attrs, MemTxResult *result);
1221 uint32_t address_space_ldl(AddressSpace *as, hwaddr addr,
1222                             MemTxAttrs attrs, MemTxResult *result);
1223 uint64_t address_space_ldq(AddressSpace *as, hwaddr addr,
1224                             MemTxAttrs attrs, MemTxResult *result);
1225 void address_space_stl_notdirty(AddressSpace *as, hwaddr addr, uint32_t val,
1226                             MemTxAttrs attrs, MemTxResult *result);
1227 void address_space_stw(AddressSpace *as, hwaddr addr, uint32_t val,
1228                             MemTxAttrs attrs, MemTxResult *result);
1229 void address_space_stl(AddressSpace *as, hwaddr addr, uint32_t val,
1230                             MemTxAttrs attrs, MemTxResult *result);
1231 void address_space_stq(AddressSpace *as, hwaddr addr, uint64_t val,
1232                             MemTxAttrs attrs, MemTxResult *result);
1233 #endif
1234 
1235 /* address_space_translate: translate an address range into an address space
1236  * into a MemoryRegion and an address range into that section.  Should be
1237  * called from an RCU critical section, to avoid that the last reference
1238  * to the returned region disappears after address_space_translate returns.
1239  *
1240  * @as: #AddressSpace to be accessed
1241  * @addr: address within that address space
1242  * @xlat: pointer to address within the returned memory region section's
1243  * #MemoryRegion.
1244  * @len: pointer to length
1245  * @is_write: indicates the transfer direction
1246  */
1247 MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
1248                                       hwaddr *xlat, hwaddr *len,
1249                                       bool is_write);
1250 
1251 /* address_space_access_valid: check for validity of accessing an address
1252  * space range
1253  *
1254  * Check whether memory is assigned to the given address space range, and
1255  * access is permitted by any IOMMU regions that are active for the address
1256  * space.
1257  *
1258  * For now, addr and len should be aligned to a page size.  This limitation
1259  * will be lifted in the future.
1260  *
1261  * @as: #AddressSpace to be accessed
1262  * @addr: address within that address space
1263  * @len: length of the area to be checked
1264  * @is_write: indicates the transfer direction
1265  */
1266 bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_write);
1267 
1268 /* address_space_map: map a physical memory region into a host virtual address
1269  *
1270  * May map a subset of the requested range, given by and returned in @plen.
1271  * May return %NULL if resources needed to perform the mapping are exhausted.
1272  * Use only for reads OR writes - not for read-modify-write operations.
1273  * Use cpu_register_map_client() to know when retrying the map operation is
1274  * likely to succeed.
1275  *
1276  * @as: #AddressSpace to be accessed
1277  * @addr: address within that address space
1278  * @plen: pointer to length of buffer; updated on return
1279  * @is_write: indicates the transfer direction
1280  */
1281 void *address_space_map(AddressSpace *as, hwaddr addr,
1282                         hwaddr *plen, bool is_write);
1283 
1284 /* address_space_unmap: Unmaps a memory region previously mapped by address_space_map()
1285  *
1286  * Will also mark the memory as dirty if @is_write == %true.  @access_len gives
1287  * the amount of memory that was actually read or written by the caller.
1288  *
1289  * @as: #AddressSpace used
1290  * @addr: address within that address space
1291  * @len: buffer length as returned by address_space_map()
1292  * @access_len: amount of data actually transferred
1293  * @is_write: indicates the transfer direction
1294  */
1295 void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
1296                          int is_write, hwaddr access_len);
1297 
1298 
1299 #endif
1300 
1301 #endif
1302