xref: /openbmc/qemu/include/exec/memory.h (revision ac06724a715864942e2b5e28f92d5d5421f0a0b0)
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 #include "exec/cpu-common.h"
20 #include "exec/hwaddr.h"
21 #include "exec/memattrs.h"
22 #include "exec/ramlist.h"
23 #include "qemu/queue.h"
24 #include "qemu/int128.h"
25 #include "qemu/notify.h"
26 #include "qom/object.h"
27 #include "qemu/rcu.h"
28 
29 #define RAM_ADDR_INVALID (~(ram_addr_t)0)
30 
31 #define MAX_PHYS_ADDR_SPACE_BITS 62
32 #define MAX_PHYS_ADDR            (((hwaddr)1 << MAX_PHYS_ADDR_SPACE_BITS) - 1)
33 
34 #define TYPE_MEMORY_REGION "qemu:memory-region"
35 #define MEMORY_REGION(obj) \
36         OBJECT_CHECK(MemoryRegion, (obj), TYPE_MEMORY_REGION)
37 
38 typedef struct MemoryRegionOps MemoryRegionOps;
39 typedef struct MemoryRegionMmio MemoryRegionMmio;
40 
41 struct MemoryRegionMmio {
42     CPUReadMemoryFunc *read[3];
43     CPUWriteMemoryFunc *write[3];
44 };
45 
46 typedef struct IOMMUTLBEntry IOMMUTLBEntry;
47 
48 /* See address_space_translate: bit 0 is read, bit 1 is write.  */
49 typedef enum {
50     IOMMU_NONE = 0,
51     IOMMU_RO   = 1,
52     IOMMU_WO   = 2,
53     IOMMU_RW   = 3,
54 } IOMMUAccessFlags;
55 
56 #define IOMMU_ACCESS_FLAG(r, w) (((r) ? IOMMU_RO : 0) | ((w) ? IOMMU_WO : 0))
57 
58 struct IOMMUTLBEntry {
59     AddressSpace    *target_as;
60     hwaddr           iova;
61     hwaddr           translated_addr;
62     hwaddr           addr_mask;  /* 0xfff = 4k translation */
63     IOMMUAccessFlags perm;
64 };
65 
66 /*
67  * Bitmap for different IOMMUNotifier capabilities. Each notifier can
68  * register with one or multiple IOMMU Notifier capability bit(s).
69  */
70 typedef enum {
71     IOMMU_NOTIFIER_NONE = 0,
72     /* Notify cache invalidations */
73     IOMMU_NOTIFIER_UNMAP = 0x1,
74     /* Notify entry changes (newly created entries) */
75     IOMMU_NOTIFIER_MAP = 0x2,
76 } IOMMUNotifierFlag;
77 
78 #define IOMMU_NOTIFIER_ALL (IOMMU_NOTIFIER_MAP | IOMMU_NOTIFIER_UNMAP)
79 
80 struct IOMMUNotifier;
81 typedef void (*IOMMUNotify)(struct IOMMUNotifier *notifier,
82                             IOMMUTLBEntry *data);
83 
84 struct IOMMUNotifier {
85     IOMMUNotify notify;
86     IOMMUNotifierFlag notifier_flags;
87     /* Notify for address space range start <= addr <= end */
88     hwaddr start;
89     hwaddr end;
90     QLIST_ENTRY(IOMMUNotifier) node;
91 };
92 typedef struct IOMMUNotifier IOMMUNotifier;
93 
94 static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
95                                        IOMMUNotifierFlag flags,
96                                        hwaddr start, hwaddr end)
97 {
98     n->notify = fn;
99     n->notifier_flags = flags;
100     n->start = start;
101     n->end = end;
102 }
103 
104 /* New-style MMIO accessors can indicate that the transaction failed.
105  * A zero (MEMTX_OK) response means success; anything else is a failure
106  * of some kind. The memory subsystem will bitwise-OR together results
107  * if it is synthesizing an operation from multiple smaller accesses.
108  */
109 #define MEMTX_OK 0
110 #define MEMTX_ERROR             (1U << 0) /* device returned an error */
111 #define MEMTX_DECODE_ERROR      (1U << 1) /* nothing at that address */
112 typedef uint32_t MemTxResult;
113 
114 /*
115  * Memory region callbacks
116  */
117 struct MemoryRegionOps {
118     /* Read from the memory region. @addr is relative to @mr; @size is
119      * in bytes. */
120     uint64_t (*read)(void *opaque,
121                      hwaddr addr,
122                      unsigned size);
123     /* Write to the memory region. @addr is relative to @mr; @size is
124      * in bytes. */
125     void (*write)(void *opaque,
126                   hwaddr addr,
127                   uint64_t data,
128                   unsigned size);
129 
130     MemTxResult (*read_with_attrs)(void *opaque,
131                                    hwaddr addr,
132                                    uint64_t *data,
133                                    unsigned size,
134                                    MemTxAttrs attrs);
135     MemTxResult (*write_with_attrs)(void *opaque,
136                                     hwaddr addr,
137                                     uint64_t data,
138                                     unsigned size,
139                                     MemTxAttrs attrs);
140 
141     enum device_endian endianness;
142     /* Guest-visible constraints: */
143     struct {
144         /* If nonzero, specify bounds on access sizes beyond which a machine
145          * check is thrown.
146          */
147         unsigned min_access_size;
148         unsigned max_access_size;
149         /* If true, unaligned accesses are supported.  Otherwise unaligned
150          * accesses throw machine checks.
151          */
152          bool unaligned;
153         /*
154          * If present, and returns #false, the transaction is not accepted
155          * by the device (and results in machine dependent behaviour such
156          * as a machine check exception).
157          */
158         bool (*accepts)(void *opaque, hwaddr addr,
159                         unsigned size, bool is_write);
160     } valid;
161     /* Internal implementation constraints: */
162     struct {
163         /* If nonzero, specifies the minimum size implemented.  Smaller sizes
164          * will be rounded upwards and a partial result will be returned.
165          */
166         unsigned min_access_size;
167         /* If nonzero, specifies the maximum size implemented.  Larger sizes
168          * will be done as a series of accesses with smaller sizes.
169          */
170         unsigned max_access_size;
171         /* If true, unaligned accesses are supported.  Otherwise all accesses
172          * are converted to (possibly multiple) naturally aligned accesses.
173          */
174         bool unaligned;
175     } impl;
176 
177     /* If .read and .write are not present, old_mmio may be used for
178      * backwards compatibility with old mmio registration
179      */
180     const MemoryRegionMmio old_mmio;
181 };
182 
183 typedef struct MemoryRegionIOMMUOps MemoryRegionIOMMUOps;
184 
185 struct MemoryRegionIOMMUOps {
186     /*
187      * Return a TLB entry that contains a given address. Flag should
188      * be the access permission of this translation operation. We can
189      * set flag to IOMMU_NONE to mean that we don't need any
190      * read/write permission checks, like, when for region replay.
191      */
192     IOMMUTLBEntry (*translate)(MemoryRegion *iommu, hwaddr addr,
193                                IOMMUAccessFlags flag);
194     /* Returns minimum supported page size */
195     uint64_t (*get_min_page_size)(MemoryRegion *iommu);
196     /* Called when IOMMU Notifier flag changed */
197     void (*notify_flag_changed)(MemoryRegion *iommu,
198                                 IOMMUNotifierFlag old_flags,
199                                 IOMMUNotifierFlag new_flags);
200     /* Set this up to provide customized IOMMU replay function */
201     void (*replay)(MemoryRegion *iommu, IOMMUNotifier *notifier);
202 };
203 
204 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
205 typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
206 
207 struct MemoryRegion {
208     Object parent_obj;
209 
210     /* All fields are private - violators will be prosecuted */
211 
212     /* The following fields should fit in a cache line */
213     bool romd_mode;
214     bool ram;
215     bool subpage;
216     bool readonly; /* For RAM regions */
217     bool rom_device;
218     bool flush_coalesced_mmio;
219     bool global_locking;
220     uint8_t dirty_log_mask;
221     RAMBlock *ram_block;
222     Object *owner;
223     const MemoryRegionIOMMUOps *iommu_ops;
224 
225     const MemoryRegionOps *ops;
226     void *opaque;
227     MemoryRegion *container;
228     Int128 size;
229     hwaddr addr;
230     void (*destructor)(MemoryRegion *mr);
231     uint64_t align;
232     bool terminates;
233     bool ram_device;
234     bool enabled;
235     bool warning_printed; /* For reservations */
236     uint8_t vga_logging_count;
237     MemoryRegion *alias;
238     hwaddr alias_offset;
239     int32_t priority;
240     QTAILQ_HEAD(subregions, MemoryRegion) subregions;
241     QTAILQ_ENTRY(MemoryRegion) subregions_link;
242     QTAILQ_HEAD(coalesced_ranges, CoalescedMemoryRange) coalesced;
243     const char *name;
244     unsigned ioeventfd_nb;
245     MemoryRegionIoeventfd *ioeventfds;
246     QLIST_HEAD(, IOMMUNotifier) iommu_notify;
247     IOMMUNotifierFlag iommu_notify_flags;
248 };
249 
250 #define IOMMU_NOTIFIER_FOREACH(n, mr) \
251     QLIST_FOREACH((n), &(mr)->iommu_notify, node)
252 
253 /**
254  * MemoryListener: callbacks structure for updates to the physical memory map
255  *
256  * Allows a component to adjust to changes in the guest-visible memory map.
257  * Use with memory_listener_register() and memory_listener_unregister().
258  */
259 struct MemoryListener {
260     void (*begin)(MemoryListener *listener);
261     void (*commit)(MemoryListener *listener);
262     void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
263     void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
264     void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
265     void (*log_start)(MemoryListener *listener, MemoryRegionSection *section,
266                       int old, int new);
267     void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section,
268                      int old, int new);
269     void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);
270     void (*log_global_start)(MemoryListener *listener);
271     void (*log_global_stop)(MemoryListener *listener);
272     void (*eventfd_add)(MemoryListener *listener, MemoryRegionSection *section,
273                         bool match_data, uint64_t data, EventNotifier *e);
274     void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
275                         bool match_data, uint64_t data, EventNotifier *e);
276     void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
277                                hwaddr addr, hwaddr len);
278     void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
279                                hwaddr addr, hwaddr len);
280     /* Lower = earlier (during add), later (during del) */
281     unsigned priority;
282     AddressSpace *address_space;
283     QTAILQ_ENTRY(MemoryListener) link;
284     QTAILQ_ENTRY(MemoryListener) link_as;
285 };
286 
287 /**
288  * AddressSpace: describes a mapping of addresses to #MemoryRegion objects
289  */
290 struct AddressSpace {
291     /* All fields are private. */
292     struct rcu_head rcu;
293     char *name;
294     MemoryRegion *root;
295     int ref_count;
296     bool malloced;
297 
298     /* Accessed via RCU.  */
299     struct FlatView *current_map;
300 
301     int ioeventfd_nb;
302     struct MemoryRegionIoeventfd *ioeventfds;
303     struct AddressSpaceDispatch *dispatch;
304     struct AddressSpaceDispatch *next_dispatch;
305     MemoryListener dispatch_listener;
306     QTAILQ_HEAD(memory_listeners_as, MemoryListener) listeners;
307     QTAILQ_ENTRY(AddressSpace) address_spaces_link;
308 };
309 
310 /**
311  * MemoryRegionSection: describes a fragment of a #MemoryRegion
312  *
313  * @mr: the region, or %NULL if empty
314  * @address_space: the address space the region is mapped in
315  * @offset_within_region: the beginning of the section, relative to @mr's start
316  * @size: the size of the section; will not exceed @mr's boundaries
317  * @offset_within_address_space: the address of the first byte of the section
318  *     relative to the region's address space
319  * @readonly: writes to this section are ignored
320  */
321 struct MemoryRegionSection {
322     MemoryRegion *mr;
323     AddressSpace *address_space;
324     hwaddr offset_within_region;
325     Int128 size;
326     hwaddr offset_within_address_space;
327     bool readonly;
328 };
329 
330 /**
331  * memory_region_init: Initialize a memory region
332  *
333  * The region typically acts as a container for other memory regions.  Use
334  * memory_region_add_subregion() to add subregions.
335  *
336  * @mr: the #MemoryRegion to be initialized
337  * @owner: the object that tracks the region's reference count
338  * @name: used for debugging; not visible to the user or ABI
339  * @size: size of the region; any subregions beyond this size will be clipped
340  */
341 void memory_region_init(MemoryRegion *mr,
342                         struct Object *owner,
343                         const char *name,
344                         uint64_t size);
345 
346 /**
347  * memory_region_ref: Add 1 to a memory region's reference count
348  *
349  * Whenever memory regions are accessed outside the BQL, they need to be
350  * preserved against hot-unplug.  MemoryRegions actually do not have their
351  * own reference count; they piggyback on a QOM object, their "owner".
352  * This function adds a reference to the owner.
353  *
354  * All MemoryRegions must have an owner if they can disappear, even if the
355  * device they belong to operates exclusively under the BQL.  This is because
356  * the region could be returned at any time by memory_region_find, and this
357  * is usually under guest control.
358  *
359  * @mr: the #MemoryRegion
360  */
361 void memory_region_ref(MemoryRegion *mr);
362 
363 /**
364  * memory_region_unref: Remove 1 to a memory region's reference count
365  *
366  * Whenever memory regions are accessed outside the BQL, they need to be
367  * preserved against hot-unplug.  MemoryRegions actually do not have their
368  * own reference count; they piggyback on a QOM object, their "owner".
369  * This function removes a reference to the owner and possibly destroys it.
370  *
371  * @mr: the #MemoryRegion
372  */
373 void memory_region_unref(MemoryRegion *mr);
374 
375 /**
376  * memory_region_init_io: Initialize an I/O memory region.
377  *
378  * Accesses into the region will cause the callbacks in @ops to be called.
379  * if @size is nonzero, subregions will be clipped to @size.
380  *
381  * @mr: the #MemoryRegion to be initialized.
382  * @owner: the object that tracks the region's reference count
383  * @ops: a structure containing read and write callbacks to be used when
384  *       I/O is performed on the region.
385  * @opaque: passed to the read and write callbacks of the @ops structure.
386  * @name: used for debugging; not visible to the user or ABI
387  * @size: size of the region.
388  */
389 void memory_region_init_io(MemoryRegion *mr,
390                            struct Object *owner,
391                            const MemoryRegionOps *ops,
392                            void *opaque,
393                            const char *name,
394                            uint64_t size);
395 
396 /**
397  * memory_region_init_ram:  Initialize RAM memory region.  Accesses into the
398  *                          region will modify memory directly.
399  *
400  * @mr: the #MemoryRegion to be initialized.
401  * @owner: the object that tracks the region's reference count
402  * @name: Region name, becomes part of RAMBlock name used in migration stream
403  *        must be unique within any device
404  * @size: size of the region.
405  * @errp: pointer to Error*, to store an error if it happens.
406  */
407 void memory_region_init_ram(MemoryRegion *mr,
408                             struct Object *owner,
409                             const char *name,
410                             uint64_t size,
411                             Error **errp);
412 
413 /**
414  * memory_region_init_resizeable_ram:  Initialize memory region with resizeable
415  *                                     RAM.  Accesses into the region will
416  *                                     modify memory directly.  Only an initial
417  *                                     portion of this RAM is actually used.
418  *                                     The used size can change across reboots.
419  *
420  * @mr: the #MemoryRegion to be initialized.
421  * @owner: the object that tracks the region's reference count
422  * @name: Region name, becomes part of RAMBlock name used in migration stream
423  *        must be unique within any device
424  * @size: used size of the region.
425  * @max_size: max size of the region.
426  * @resized: callback to notify owner about used size change.
427  * @errp: pointer to Error*, to store an error if it happens.
428  */
429 void memory_region_init_resizeable_ram(MemoryRegion *mr,
430                                        struct Object *owner,
431                                        const char *name,
432                                        uint64_t size,
433                                        uint64_t max_size,
434                                        void (*resized)(const char*,
435                                                        uint64_t length,
436                                                        void *host),
437                                        Error **errp);
438 #ifdef __linux__
439 /**
440  * memory_region_init_ram_from_file:  Initialize RAM memory region with a
441  *                                    mmap-ed backend.
442  *
443  * @mr: the #MemoryRegion to be initialized.
444  * @owner: the object that tracks the region's reference count
445  * @name: Region name, becomes part of RAMBlock name used in migration stream
446  *        must be unique within any device
447  * @size: size of the region.
448  * @share: %true if memory must be mmaped with the MAP_SHARED flag
449  * @path: the path in which to allocate the RAM.
450  * @errp: pointer to Error*, to store an error if it happens.
451  */
452 void memory_region_init_ram_from_file(MemoryRegion *mr,
453                                       struct Object *owner,
454                                       const char *name,
455                                       uint64_t size,
456                                       bool share,
457                                       const char *path,
458                                       Error **errp);
459 #endif
460 
461 /**
462  * memory_region_init_ram_ptr:  Initialize RAM memory region from a
463  *                              user-provided pointer.  Accesses into the
464  *                              region will modify memory directly.
465  *
466  * @mr: the #MemoryRegion to be initialized.
467  * @owner: the object that tracks the region's reference count
468  * @name: Region name, becomes part of RAMBlock name used in migration stream
469  *        must be unique within any device
470  * @size: size of the region.
471  * @ptr: memory to be mapped; must contain at least @size bytes.
472  */
473 void memory_region_init_ram_ptr(MemoryRegion *mr,
474                                 struct Object *owner,
475                                 const char *name,
476                                 uint64_t size,
477                                 void *ptr);
478 
479 /**
480  * memory_region_init_ram_device_ptr:  Initialize RAM device memory region from
481  *                                     a user-provided pointer.
482  *
483  * A RAM device represents a mapping to a physical device, such as to a PCI
484  * MMIO BAR of an vfio-pci assigned device.  The memory region may be mapped
485  * into the VM address space and access to the region will modify memory
486  * directly.  However, the memory region should not be included in a memory
487  * dump (device may not be enabled/mapped at the time of the dump), and
488  * operations incompatible with manipulating MMIO should be avoided.  Replaces
489  * skip_dump flag.
490  *
491  * @mr: the #MemoryRegion to be initialized.
492  * @owner: the object that tracks the region's reference count
493  * @name: the name of the region.
494  * @size: size of the region.
495  * @ptr: memory to be mapped; must contain at least @size bytes.
496  */
497 void memory_region_init_ram_device_ptr(MemoryRegion *mr,
498                                        struct Object *owner,
499                                        const char *name,
500                                        uint64_t size,
501                                        void *ptr);
502 
503 /**
504  * memory_region_init_alias: Initialize a memory region that aliases all or a
505  *                           part of another memory region.
506  *
507  * @mr: the #MemoryRegion to be initialized.
508  * @owner: the object that tracks the region's reference count
509  * @name: used for debugging; not visible to the user or ABI
510  * @orig: the region to be referenced; @mr will be equivalent to
511  *        @orig between @offset and @offset + @size - 1.
512  * @offset: start of the section in @orig to be referenced.
513  * @size: size of the region.
514  */
515 void memory_region_init_alias(MemoryRegion *mr,
516                               struct Object *owner,
517                               const char *name,
518                               MemoryRegion *orig,
519                               hwaddr offset,
520                               uint64_t size);
521 
522 /**
523  * memory_region_init_rom: Initialize a ROM memory region.
524  *
525  * This has the same effect as calling memory_region_init_ram()
526  * and then marking the resulting region read-only with
527  * memory_region_set_readonly().
528  *
529  * @mr: the #MemoryRegion to be initialized.
530  * @owner: the object that tracks the region's reference count
531  * @name: Region name, becomes part of RAMBlock name used in migration stream
532  *        must be unique within any device
533  * @size: size of the region.
534  * @errp: pointer to Error*, to store an error if it happens.
535  */
536 void memory_region_init_rom(MemoryRegion *mr,
537                             struct Object *owner,
538                             const char *name,
539                             uint64_t size,
540                             Error **errp);
541 
542 /**
543  * memory_region_init_rom_device:  Initialize a ROM memory region.  Writes are
544  *                                 handled via callbacks.
545  *
546  * @mr: the #MemoryRegion to be initialized.
547  * @owner: the object that tracks the region's reference count
548  * @ops: callbacks for write access handling (must not be NULL).
549  * @name: Region name, becomes part of RAMBlock name used in migration stream
550  *        must be unique within any device
551  * @size: size of the region.
552  * @errp: pointer to Error*, to store an error if it happens.
553  */
554 void memory_region_init_rom_device(MemoryRegion *mr,
555                                    struct Object *owner,
556                                    const MemoryRegionOps *ops,
557                                    void *opaque,
558                                    const char *name,
559                                    uint64_t size,
560                                    Error **errp);
561 
562 /**
563  * memory_region_init_reservation: Initialize a memory region that reserves
564  *                                 I/O space.
565  *
566  * A reservation region primariy serves debugging purposes.  It claims I/O
567  * space that is not supposed to be handled by QEMU itself.  Any access via
568  * the memory API will cause an abort().
569  * This function is deprecated. Use memory_region_init_io() with NULL
570  * callbacks instead.
571  *
572  * @mr: the #MemoryRegion to be initialized
573  * @owner: the object that tracks the region's reference count
574  * @name: used for debugging; not visible to the user or ABI
575  * @size: size of the region.
576  */
577 static inline void memory_region_init_reservation(MemoryRegion *mr,
578                                     Object *owner,
579                                     const char *name,
580                                     uint64_t size)
581 {
582     memory_region_init_io(mr, owner, NULL, mr, name, size);
583 }
584 
585 /**
586  * memory_region_init_iommu: Initialize a memory region that translates
587  * addresses
588  *
589  * An IOMMU region translates addresses and forwards accesses to a target
590  * memory region.
591  *
592  * @mr: the #MemoryRegion to be initialized
593  * @owner: the object that tracks the region's reference count
594  * @ops: a function that translates addresses into the @target region
595  * @name: used for debugging; not visible to the user or ABI
596  * @size: size of the region.
597  */
598 void memory_region_init_iommu(MemoryRegion *mr,
599                               struct Object *owner,
600                               const MemoryRegionIOMMUOps *ops,
601                               const char *name,
602                               uint64_t size);
603 
604 /**
605  * memory_region_owner: get a memory region's owner.
606  *
607  * @mr: the memory region being queried.
608  */
609 struct Object *memory_region_owner(MemoryRegion *mr);
610 
611 /**
612  * memory_region_size: get a memory region's size.
613  *
614  * @mr: the memory region being queried.
615  */
616 uint64_t memory_region_size(MemoryRegion *mr);
617 
618 /**
619  * memory_region_is_ram: check whether a memory region is random access
620  *
621  * Returns %true is a memory region is random access.
622  *
623  * @mr: the memory region being queried
624  */
625 static inline bool memory_region_is_ram(MemoryRegion *mr)
626 {
627     return mr->ram;
628 }
629 
630 /**
631  * memory_region_is_ram_device: check whether a memory region is a ram device
632  *
633  * Returns %true is a memory region is a device backed ram region
634  *
635  * @mr: the memory region being queried
636  */
637 bool memory_region_is_ram_device(MemoryRegion *mr);
638 
639 /**
640  * memory_region_is_romd: check whether a memory region is in ROMD mode
641  *
642  * Returns %true if a memory region is a ROM device and currently set to allow
643  * direct reads.
644  *
645  * @mr: the memory region being queried
646  */
647 static inline bool memory_region_is_romd(MemoryRegion *mr)
648 {
649     return mr->rom_device && mr->romd_mode;
650 }
651 
652 /**
653  * memory_region_is_iommu: check whether a memory region is an iommu
654  *
655  * Returns %true is a memory region is an iommu.
656  *
657  * @mr: the memory region being queried
658  */
659 static inline bool memory_region_is_iommu(MemoryRegion *mr)
660 {
661     if (mr->alias) {
662         return memory_region_is_iommu(mr->alias);
663     }
664     return mr->iommu_ops;
665 }
666 
667 
668 /**
669  * memory_region_iommu_get_min_page_size: get minimum supported page size
670  * for an iommu
671  *
672  * Returns minimum supported page size for an iommu.
673  *
674  * @mr: the memory region being queried
675  */
676 uint64_t memory_region_iommu_get_min_page_size(MemoryRegion *mr);
677 
678 /**
679  * memory_region_notify_iommu: notify a change in an IOMMU translation entry.
680  *
681  * The notification type will be decided by entry.perm bits:
682  *
683  * - For UNMAP (cache invalidation) notifies: set entry.perm to IOMMU_NONE.
684  * - For MAP (newly added entry) notifies: set entry.perm to the
685  *   permission of the page (which is definitely !IOMMU_NONE).
686  *
687  * Note: for any IOMMU implementation, an in-place mapping change
688  * should be notified with an UNMAP followed by a MAP.
689  *
690  * @mr: the memory region that was changed
691  * @entry: the new entry in the IOMMU translation table.  The entry
692  *         replaces all old entries for the same virtual I/O address range.
693  *         Deleted entries have .@perm == 0.
694  */
695 void memory_region_notify_iommu(MemoryRegion *mr,
696                                 IOMMUTLBEntry entry);
697 
698 /**
699  * memory_region_notify_one: notify a change in an IOMMU translation
700  *                           entry to a single notifier
701  *
702  * This works just like memory_region_notify_iommu(), but it only
703  * notifies a specific notifier, not all of them.
704  *
705  * @notifier: the notifier to be notified
706  * @entry: the new entry in the IOMMU translation table.  The entry
707  *         replaces all old entries for the same virtual I/O address range.
708  *         Deleted entries have .@perm == 0.
709  */
710 void memory_region_notify_one(IOMMUNotifier *notifier,
711                               IOMMUTLBEntry *entry);
712 
713 /**
714  * memory_region_register_iommu_notifier: register a notifier for changes to
715  * IOMMU translation entries.
716  *
717  * @mr: the memory region to observe
718  * @n: the IOMMUNotifier to be added; the notify callback receives a
719  *     pointer to an #IOMMUTLBEntry as the opaque value; the pointer
720  *     ceases to be valid on exit from the notifier.
721  */
722 void memory_region_register_iommu_notifier(MemoryRegion *mr,
723                                            IOMMUNotifier *n);
724 
725 /**
726  * memory_region_iommu_replay: replay existing IOMMU translations to
727  * a notifier with the minimum page granularity returned by
728  * mr->iommu_ops->get_page_size().
729  *
730  * @mr: the memory region to observe
731  * @n: the notifier to which to replay iommu mappings
732  */
733 void memory_region_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n);
734 
735 /**
736  * memory_region_iommu_replay_all: replay existing IOMMU translations
737  * to all the notifiers registered.
738  *
739  * @mr: the memory region to observe
740  */
741 void memory_region_iommu_replay_all(MemoryRegion *mr);
742 
743 /**
744  * memory_region_unregister_iommu_notifier: unregister a notifier for
745  * changes to IOMMU translation entries.
746  *
747  * @mr: the memory region which was observed and for which notity_stopped()
748  *      needs to be called
749  * @n: the notifier to be removed.
750  */
751 void memory_region_unregister_iommu_notifier(MemoryRegion *mr,
752                                              IOMMUNotifier *n);
753 
754 /**
755  * memory_region_name: get a memory region's name
756  *
757  * Returns the string that was used to initialize the memory region.
758  *
759  * @mr: the memory region being queried
760  */
761 const char *memory_region_name(const MemoryRegion *mr);
762 
763 /**
764  * memory_region_is_logging: return whether a memory region is logging writes
765  *
766  * Returns %true if the memory region is logging writes for the given client
767  *
768  * @mr: the memory region being queried
769  * @client: the client being queried
770  */
771 bool memory_region_is_logging(MemoryRegion *mr, uint8_t client);
772 
773 /**
774  * memory_region_get_dirty_log_mask: return the clients for which a
775  * memory region is logging writes.
776  *
777  * Returns a bitmap of clients, in which the DIRTY_MEMORY_* constants
778  * are the bit indices.
779  *
780  * @mr: the memory region being queried
781  */
782 uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr);
783 
784 /**
785  * memory_region_is_rom: check whether a memory region is ROM
786  *
787  * Returns %true is a memory region is read-only memory.
788  *
789  * @mr: the memory region being queried
790  */
791 static inline bool memory_region_is_rom(MemoryRegion *mr)
792 {
793     return mr->ram && mr->readonly;
794 }
795 
796 
797 /**
798  * memory_region_get_fd: Get a file descriptor backing a RAM memory region.
799  *
800  * Returns a file descriptor backing a file-based RAM memory region,
801  * or -1 if the region is not a file-based RAM memory region.
802  *
803  * @mr: the RAM or alias memory region being queried.
804  */
805 int memory_region_get_fd(MemoryRegion *mr);
806 
807 /**
808  * memory_region_set_fd: Mark a RAM memory region as backed by a
809  * file descriptor.
810  *
811  * This function is typically used after memory_region_init_ram_ptr().
812  *
813  * @mr: the memory region being queried.
814  * @fd: the file descriptor that backs @mr.
815  */
816 void memory_region_set_fd(MemoryRegion *mr, int fd);
817 
818 /**
819  * memory_region_from_host: Convert a pointer into a RAM memory region
820  * and an offset within it.
821  *
822  * Given a host pointer inside a RAM memory region (created with
823  * memory_region_init_ram() or memory_region_init_ram_ptr()), return
824  * the MemoryRegion and the offset within it.
825  *
826  * Use with care; by the time this function returns, the returned pointer is
827  * not protected by RCU anymore.  If the caller is not within an RCU critical
828  * section and does not hold the iothread lock, it must have other means of
829  * protecting the pointer, such as a reference to the region that includes
830  * the incoming ram_addr_t.
831  *
832  * @mr: the memory region being queried.
833  */
834 MemoryRegion *memory_region_from_host(void *ptr, ram_addr_t *offset);
835 
836 /**
837  * memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
838  *
839  * Returns a host pointer to a RAM memory region (created with
840  * memory_region_init_ram() or memory_region_init_ram_ptr()).
841  *
842  * Use with care; by the time this function returns, the returned pointer is
843  * not protected by RCU anymore.  If the caller is not within an RCU critical
844  * section and does not hold the iothread lock, it must have other means of
845  * protecting the pointer, such as a reference to the region that includes
846  * the incoming ram_addr_t.
847  *
848  * @mr: the memory region being queried.
849  */
850 void *memory_region_get_ram_ptr(MemoryRegion *mr);
851 
852 /* memory_region_ram_resize: Resize a RAM region.
853  *
854  * Only legal before guest might have detected the memory size: e.g. on
855  * incoming migration, or right after reset.
856  *
857  * @mr: a memory region created with @memory_region_init_resizeable_ram.
858  * @newsize: the new size the region
859  * @errp: pointer to Error*, to store an error if it happens.
860  */
861 void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize,
862                               Error **errp);
863 
864 /**
865  * memory_region_set_log: Turn dirty logging on or off for a region.
866  *
867  * Turns dirty logging on or off for a specified client (display, migration).
868  * Only meaningful for RAM regions.
869  *
870  * @mr: the memory region being updated.
871  * @log: whether dirty logging is to be enabled or disabled.
872  * @client: the user of the logging information; %DIRTY_MEMORY_VGA only.
873  */
874 void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);
875 
876 /**
877  * memory_region_get_dirty: Check whether a range of bytes is dirty
878  *                          for a specified client.
879  *
880  * Checks whether a range of bytes has been written to since the last
881  * call to memory_region_reset_dirty() with the same @client.  Dirty logging
882  * must be enabled.
883  *
884  * @mr: the memory region being queried.
885  * @addr: the address (relative to the start of the region) being queried.
886  * @size: the size of the range being queried.
887  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
888  *          %DIRTY_MEMORY_VGA.
889  */
890 bool memory_region_get_dirty(MemoryRegion *mr, hwaddr addr,
891                              hwaddr size, unsigned client);
892 
893 /**
894  * memory_region_set_dirty: Mark a range of bytes as dirty in a memory region.
895  *
896  * Marks a range of bytes as dirty, after it has been dirtied outside
897  * guest code.
898  *
899  * @mr: the memory region being dirtied.
900  * @addr: the address (relative to the start of the region) being dirtied.
901  * @size: size of the range being dirtied.
902  */
903 void memory_region_set_dirty(MemoryRegion *mr, hwaddr addr,
904                              hwaddr size);
905 
906 /**
907  * memory_region_test_and_clear_dirty: Check whether a range of bytes is dirty
908  *                                     for a specified client. It clears them.
909  *
910  * Checks whether a range of bytes has been written to since the last
911  * call to memory_region_reset_dirty() with the same @client.  Dirty logging
912  * must be enabled.
913  *
914  * @mr: the memory region being queried.
915  * @addr: the address (relative to the start of the region) being queried.
916  * @size: the size of the range being queried.
917  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
918  *          %DIRTY_MEMORY_VGA.
919  */
920 bool memory_region_test_and_clear_dirty(MemoryRegion *mr, hwaddr addr,
921                                         hwaddr size, unsigned client);
922 
923 /**
924  * memory_region_snapshot_and_clear_dirty: Get a snapshot of the dirty
925  *                                         bitmap and clear it.
926  *
927  * Creates a snapshot of the dirty bitmap, clears the dirty bitmap and
928  * returns the snapshot.  The snapshot can then be used to query dirty
929  * status, using memory_region_snapshot_get_dirty.  Unlike
930  * memory_region_test_and_clear_dirty this allows to query the same
931  * page multiple times, which is especially useful for display updates
932  * where the scanlines often are not page aligned.
933  *
934  * The dirty bitmap region which gets copyed into the snapshot (and
935  * cleared afterwards) can be larger than requested.  The boundaries
936  * are rounded up/down so complete bitmap longs (covering 64 pages on
937  * 64bit hosts) can be copied over into the bitmap snapshot.  Which
938  * isn't a problem for display updates as the extra pages are outside
939  * the visible area, and in case the visible area changes a full
940  * display redraw is due anyway.  Should other use cases for this
941  * function emerge we might have to revisit this implementation
942  * detail.
943  *
944  * Use g_free to release DirtyBitmapSnapshot.
945  *
946  * @mr: the memory region being queried.
947  * @addr: the address (relative to the start of the region) being queried.
948  * @size: the size of the range being queried.
949  * @client: the user of the logging information; typically %DIRTY_MEMORY_VGA.
950  */
951 DirtyBitmapSnapshot *memory_region_snapshot_and_clear_dirty(MemoryRegion *mr,
952                                                             hwaddr addr,
953                                                             hwaddr size,
954                                                             unsigned client);
955 
956 /**
957  * memory_region_snapshot_get_dirty: Check whether a range of bytes is dirty
958  *                                   in the specified dirty bitmap snapshot.
959  *
960  * @mr: the memory region being queried.
961  * @snap: the dirty bitmap snapshot
962  * @addr: the address (relative to the start of the region) being queried.
963  * @size: the size of the range being queried.
964  */
965 bool memory_region_snapshot_get_dirty(MemoryRegion *mr,
966                                       DirtyBitmapSnapshot *snap,
967                                       hwaddr addr, hwaddr size);
968 
969 /**
970  * memory_region_sync_dirty_bitmap: Synchronize a region's dirty bitmap with
971  *                                  any external TLBs (e.g. kvm)
972  *
973  * Flushes dirty information from accelerators such as kvm and vhost-net
974  * and makes it available to users of the memory API.
975  *
976  * @mr: the region being flushed.
977  */
978 void memory_region_sync_dirty_bitmap(MemoryRegion *mr);
979 
980 /**
981  * memory_region_reset_dirty: Mark a range of pages as clean, for a specified
982  *                            client.
983  *
984  * Marks a range of pages as no longer dirty.
985  *
986  * @mr: the region being updated.
987  * @addr: the start of the subrange being cleaned.
988  * @size: the size of the subrange being cleaned.
989  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
990  *          %DIRTY_MEMORY_VGA.
991  */
992 void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
993                                hwaddr size, unsigned client);
994 
995 /**
996  * memory_region_set_readonly: Turn a memory region read-only (or read-write)
997  *
998  * Allows a memory region to be marked as read-only (turning it into a ROM).
999  * only useful on RAM regions.
1000  *
1001  * @mr: the region being updated.
1002  * @readonly: whether rhe region is to be ROM or RAM.
1003  */
1004 void memory_region_set_readonly(MemoryRegion *mr, bool readonly);
1005 
1006 /**
1007  * memory_region_rom_device_set_romd: enable/disable ROMD mode
1008  *
1009  * Allows a ROM device (initialized with memory_region_init_rom_device() to
1010  * set to ROMD mode (default) or MMIO mode.  When it is in ROMD mode, the
1011  * device is mapped to guest memory and satisfies read access directly.
1012  * When in MMIO mode, reads are forwarded to the #MemoryRegion.read function.
1013  * Writes are always handled by the #MemoryRegion.write function.
1014  *
1015  * @mr: the memory region to be updated
1016  * @romd_mode: %true to put the region into ROMD mode
1017  */
1018 void memory_region_rom_device_set_romd(MemoryRegion *mr, bool romd_mode);
1019 
1020 /**
1021  * memory_region_set_coalescing: Enable memory coalescing for the region.
1022  *
1023  * Enabled writes to a region to be queued for later processing. MMIO ->write
1024  * callbacks may be delayed until a non-coalesced MMIO is issued.
1025  * Only useful for IO regions.  Roughly similar to write-combining hardware.
1026  *
1027  * @mr: the memory region to be write coalesced
1028  */
1029 void memory_region_set_coalescing(MemoryRegion *mr);
1030 
1031 /**
1032  * memory_region_add_coalescing: Enable memory coalescing for a sub-range of
1033  *                               a region.
1034  *
1035  * Like memory_region_set_coalescing(), but works on a sub-range of a region.
1036  * Multiple calls can be issued coalesced disjoint ranges.
1037  *
1038  * @mr: the memory region to be updated.
1039  * @offset: the start of the range within the region to be coalesced.
1040  * @size: the size of the subrange to be coalesced.
1041  */
1042 void memory_region_add_coalescing(MemoryRegion *mr,
1043                                   hwaddr offset,
1044                                   uint64_t size);
1045 
1046 /**
1047  * memory_region_clear_coalescing: Disable MMIO coalescing for the region.
1048  *
1049  * Disables any coalescing caused by memory_region_set_coalescing() or
1050  * memory_region_add_coalescing().  Roughly equivalent to uncacheble memory
1051  * hardware.
1052  *
1053  * @mr: the memory region to be updated.
1054  */
1055 void memory_region_clear_coalescing(MemoryRegion *mr);
1056 
1057 /**
1058  * memory_region_set_flush_coalesced: Enforce memory coalescing flush before
1059  *                                    accesses.
1060  *
1061  * Ensure that pending coalesced MMIO request are flushed before the memory
1062  * region is accessed. This property is automatically enabled for all regions
1063  * passed to memory_region_set_coalescing() and memory_region_add_coalescing().
1064  *
1065  * @mr: the memory region to be updated.
1066  */
1067 void memory_region_set_flush_coalesced(MemoryRegion *mr);
1068 
1069 /**
1070  * memory_region_clear_flush_coalesced: Disable memory coalescing flush before
1071  *                                      accesses.
1072  *
1073  * Clear the automatic coalesced MMIO flushing enabled via
1074  * memory_region_set_flush_coalesced. Note that this service has no effect on
1075  * memory regions that have MMIO coalescing enabled for themselves. For them,
1076  * automatic flushing will stop once coalescing is disabled.
1077  *
1078  * @mr: the memory region to be updated.
1079  */
1080 void memory_region_clear_flush_coalesced(MemoryRegion *mr);
1081 
1082 /**
1083  * memory_region_set_global_locking: Declares the access processing requires
1084  *                                   QEMU's global lock.
1085  *
1086  * When this is invoked, accesses to the memory region will be processed while
1087  * holding the global lock of QEMU. This is the default behavior of memory
1088  * regions.
1089  *
1090  * @mr: the memory region to be updated.
1091  */
1092 void memory_region_set_global_locking(MemoryRegion *mr);
1093 
1094 /**
1095  * memory_region_clear_global_locking: Declares that access processing does
1096  *                                     not depend on the QEMU global lock.
1097  *
1098  * By clearing this property, accesses to the memory region will be processed
1099  * outside of QEMU's global lock (unless the lock is held on when issuing the
1100  * access request). In this case, the device model implementing the access
1101  * handlers is responsible for synchronization of concurrency.
1102  *
1103  * @mr: the memory region to be updated.
1104  */
1105 void memory_region_clear_global_locking(MemoryRegion *mr);
1106 
1107 /**
1108  * memory_region_add_eventfd: Request an eventfd to be triggered when a word
1109  *                            is written to a location.
1110  *
1111  * Marks a word in an IO region (initialized with memory_region_init_io())
1112  * as a trigger for an eventfd event.  The I/O callback will not be called.
1113  * The caller must be prepared to handle failure (that is, take the required
1114  * action if the callback _is_ called).
1115  *
1116  * @mr: the memory region being updated.
1117  * @addr: the address within @mr that is to be monitored
1118  * @size: the size of the access to trigger the eventfd
1119  * @match_data: whether to match against @data, instead of just @addr
1120  * @data: the data to match against the guest write
1121  * @fd: the eventfd to be triggered when @addr, @size, and @data all match.
1122  **/
1123 void memory_region_add_eventfd(MemoryRegion *mr,
1124                                hwaddr addr,
1125                                unsigned size,
1126                                bool match_data,
1127                                uint64_t data,
1128                                EventNotifier *e);
1129 
1130 /**
1131  * memory_region_del_eventfd: Cancel an eventfd.
1132  *
1133  * Cancels an eventfd trigger requested by a previous
1134  * memory_region_add_eventfd() call.
1135  *
1136  * @mr: the memory region being updated.
1137  * @addr: the address within @mr that is to be monitored
1138  * @size: the size of the access to trigger the eventfd
1139  * @match_data: whether to match against @data, instead of just @addr
1140  * @data: the data to match against the guest write
1141  * @fd: the eventfd to be triggered when @addr, @size, and @data all match.
1142  */
1143 void memory_region_del_eventfd(MemoryRegion *mr,
1144                                hwaddr addr,
1145                                unsigned size,
1146                                bool match_data,
1147                                uint64_t data,
1148                                EventNotifier *e);
1149 
1150 /**
1151  * memory_region_add_subregion: Add a subregion to a container.
1152  *
1153  * Adds a subregion at @offset.  The subregion may not overlap with other
1154  * subregions (except for those explicitly marked as overlapping).  A region
1155  * may only be added once as a subregion (unless removed with
1156  * memory_region_del_subregion()); use memory_region_init_alias() if you
1157  * want a region to be a subregion in multiple locations.
1158  *
1159  * @mr: the region to contain the new subregion; must be a container
1160  *      initialized with memory_region_init().
1161  * @offset: the offset relative to @mr where @subregion is added.
1162  * @subregion: the subregion to be added.
1163  */
1164 void memory_region_add_subregion(MemoryRegion *mr,
1165                                  hwaddr offset,
1166                                  MemoryRegion *subregion);
1167 /**
1168  * memory_region_add_subregion_overlap: Add a subregion to a container
1169  *                                      with overlap.
1170  *
1171  * Adds a subregion at @offset.  The subregion may overlap with other
1172  * subregions.  Conflicts are resolved by having a higher @priority hide a
1173  * lower @priority. Subregions without priority are taken as @priority 0.
1174  * A region may only be added once as a subregion (unless removed with
1175  * memory_region_del_subregion()); use memory_region_init_alias() if you
1176  * want a region to be a subregion in multiple locations.
1177  *
1178  * @mr: the region to contain the new subregion; must be a container
1179  *      initialized with memory_region_init().
1180  * @offset: the offset relative to @mr where @subregion is added.
1181  * @subregion: the subregion to be added.
1182  * @priority: used for resolving overlaps; highest priority wins.
1183  */
1184 void memory_region_add_subregion_overlap(MemoryRegion *mr,
1185                                          hwaddr offset,
1186                                          MemoryRegion *subregion,
1187                                          int priority);
1188 
1189 /**
1190  * memory_region_get_ram_addr: Get the ram address associated with a memory
1191  *                             region
1192  */
1193 ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr);
1194 
1195 uint64_t memory_region_get_alignment(const MemoryRegion *mr);
1196 /**
1197  * memory_region_del_subregion: Remove a subregion.
1198  *
1199  * Removes a subregion from its container.
1200  *
1201  * @mr: the container to be updated.
1202  * @subregion: the region being removed; must be a current subregion of @mr.
1203  */
1204 void memory_region_del_subregion(MemoryRegion *mr,
1205                                  MemoryRegion *subregion);
1206 
1207 /*
1208  * memory_region_set_enabled: dynamically enable or disable a region
1209  *
1210  * Enables or disables a memory region.  A disabled memory region
1211  * ignores all accesses to itself and its subregions.  It does not
1212  * obscure sibling subregions with lower priority - it simply behaves as
1213  * if it was removed from the hierarchy.
1214  *
1215  * Regions default to being enabled.
1216  *
1217  * @mr: the region to be updated
1218  * @enabled: whether to enable or disable the region
1219  */
1220 void memory_region_set_enabled(MemoryRegion *mr, bool enabled);
1221 
1222 /*
1223  * memory_region_set_address: dynamically update the address of a region
1224  *
1225  * Dynamically updates the address of a region, relative to its container.
1226  * May be used on regions are currently part of a memory hierarchy.
1227  *
1228  * @mr: the region to be updated
1229  * @addr: new address, relative to container region
1230  */
1231 void memory_region_set_address(MemoryRegion *mr, hwaddr addr);
1232 
1233 /*
1234  * memory_region_set_size: dynamically update the size of a region.
1235  *
1236  * Dynamically updates the size of a region.
1237  *
1238  * @mr: the region to be updated
1239  * @size: used size of the region.
1240  */
1241 void memory_region_set_size(MemoryRegion *mr, uint64_t size);
1242 
1243 /*
1244  * memory_region_set_alias_offset: dynamically update a memory alias's offset
1245  *
1246  * Dynamically updates the offset into the target region that an alias points
1247  * to, as if the fourth argument to memory_region_init_alias() has changed.
1248  *
1249  * @mr: the #MemoryRegion to be updated; should be an alias.
1250  * @offset: the new offset into the target memory region
1251  */
1252 void memory_region_set_alias_offset(MemoryRegion *mr,
1253                                     hwaddr offset);
1254 
1255 /**
1256  * memory_region_present: checks if an address relative to a @container
1257  * translates into #MemoryRegion within @container
1258  *
1259  * Answer whether a #MemoryRegion within @container covers the address
1260  * @addr.
1261  *
1262  * @container: a #MemoryRegion within which @addr is a relative address
1263  * @addr: the area within @container to be searched
1264  */
1265 bool memory_region_present(MemoryRegion *container, hwaddr addr);
1266 
1267 /**
1268  * memory_region_is_mapped: returns true if #MemoryRegion is mapped
1269  * into any address space.
1270  *
1271  * @mr: a #MemoryRegion which should be checked if it's mapped
1272  */
1273 bool memory_region_is_mapped(MemoryRegion *mr);
1274 
1275 /**
1276  * memory_region_find: translate an address/size relative to a
1277  * MemoryRegion into a #MemoryRegionSection.
1278  *
1279  * Locates the first #MemoryRegion within @mr that overlaps the range
1280  * given by @addr and @size.
1281  *
1282  * Returns a #MemoryRegionSection that describes a contiguous overlap.
1283  * It will have the following characteristics:
1284  *    .@size = 0 iff no overlap was found
1285  *    .@mr is non-%NULL iff an overlap was found
1286  *
1287  * Remember that in the return value the @offset_within_region is
1288  * relative to the returned region (in the .@mr field), not to the
1289  * @mr argument.
1290  *
1291  * Similarly, the .@offset_within_address_space is relative to the
1292  * address space that contains both regions, the passed and the
1293  * returned one.  However, in the special case where the @mr argument
1294  * has no container (and thus is the root of the address space), the
1295  * following will hold:
1296  *    .@offset_within_address_space >= @addr
1297  *    .@offset_within_address_space + .@size <= @addr + @size
1298  *
1299  * @mr: a MemoryRegion within which @addr is a relative address
1300  * @addr: start of the area within @as to be searched
1301  * @size: size of the area to be searched
1302  */
1303 MemoryRegionSection memory_region_find(MemoryRegion *mr,
1304                                        hwaddr addr, uint64_t size);
1305 
1306 /**
1307  * memory_global_dirty_log_sync: synchronize the dirty log for all memory
1308  *
1309  * Synchronizes the dirty page log for all address spaces.
1310  */
1311 void memory_global_dirty_log_sync(void);
1312 
1313 /**
1314  * memory_region_transaction_begin: Start a transaction.
1315  *
1316  * During a transaction, changes will be accumulated and made visible
1317  * only when the transaction ends (is committed).
1318  */
1319 void memory_region_transaction_begin(void);
1320 
1321 /**
1322  * memory_region_transaction_commit: Commit a transaction and make changes
1323  *                                   visible to the guest.
1324  */
1325 void memory_region_transaction_commit(void);
1326 
1327 /**
1328  * memory_listener_register: register callbacks to be called when memory
1329  *                           sections are mapped or unmapped into an address
1330  *                           space
1331  *
1332  * @listener: an object containing the callbacks to be called
1333  * @filter: if non-%NULL, only regions in this address space will be observed
1334  */
1335 void memory_listener_register(MemoryListener *listener, AddressSpace *filter);
1336 
1337 /**
1338  * memory_listener_unregister: undo the effect of memory_listener_register()
1339  *
1340  * @listener: an object containing the callbacks to be removed
1341  */
1342 void memory_listener_unregister(MemoryListener *listener);
1343 
1344 /**
1345  * memory_global_dirty_log_start: begin dirty logging for all regions
1346  */
1347 void memory_global_dirty_log_start(void);
1348 
1349 /**
1350  * memory_global_dirty_log_stop: end dirty logging for all regions
1351  */
1352 void memory_global_dirty_log_stop(void);
1353 
1354 void mtree_info(fprintf_function mon_printf, void *f, bool flatview);
1355 
1356 /**
1357  * memory_region_dispatch_read: perform a read directly to the specified
1358  * MemoryRegion.
1359  *
1360  * @mr: #MemoryRegion to access
1361  * @addr: address within that region
1362  * @pval: pointer to uint64_t which the data is written to
1363  * @size: size of the access in bytes
1364  * @attrs: memory transaction attributes to use for the access
1365  */
1366 MemTxResult memory_region_dispatch_read(MemoryRegion *mr,
1367                                         hwaddr addr,
1368                                         uint64_t *pval,
1369                                         unsigned size,
1370                                         MemTxAttrs attrs);
1371 /**
1372  * memory_region_dispatch_write: perform a write directly to the specified
1373  * MemoryRegion.
1374  *
1375  * @mr: #MemoryRegion to access
1376  * @addr: address within that region
1377  * @data: data to write
1378  * @size: size of the access in bytes
1379  * @attrs: memory transaction attributes to use for the access
1380  */
1381 MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
1382                                          hwaddr addr,
1383                                          uint64_t data,
1384                                          unsigned size,
1385                                          MemTxAttrs attrs);
1386 
1387 /**
1388  * address_space_init: initializes an address space
1389  *
1390  * @as: an uninitialized #AddressSpace
1391  * @root: a #MemoryRegion that routes addresses for the address space
1392  * @name: an address space name.  The name is only used for debugging
1393  *        output.
1394  */
1395 void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name);
1396 
1397 /**
1398  * address_space_init_shareable: return an address space for a memory region,
1399  *                               creating it if it does not already exist
1400  *
1401  * @root: a #MemoryRegion that routes addresses for the address space
1402  * @name: an address space name.  The name is only used for debugging
1403  *        output.
1404  *
1405  * This function will return a pointer to an existing AddressSpace
1406  * which was initialized with the specified MemoryRegion, or it will
1407  * create and initialize one if it does not already exist. The ASes
1408  * are reference-counted, so the memory will be freed automatically
1409  * when the AddressSpace is destroyed via address_space_destroy.
1410  */
1411 AddressSpace *address_space_init_shareable(MemoryRegion *root,
1412                                            const char *name);
1413 
1414 /**
1415  * address_space_destroy: destroy an address space
1416  *
1417  * Releases all resources associated with an address space.  After an address space
1418  * is destroyed, its root memory region (given by address_space_init()) may be destroyed
1419  * as well.
1420  *
1421  * @as: address space to be destroyed
1422  */
1423 void address_space_destroy(AddressSpace *as);
1424 
1425 /**
1426  * address_space_rw: read from or write to an address space.
1427  *
1428  * Return a MemTxResult indicating whether the operation succeeded
1429  * or failed (eg unassigned memory, device rejected the transaction,
1430  * IOMMU fault).
1431  *
1432  * @as: #AddressSpace to be accessed
1433  * @addr: address within that address space
1434  * @attrs: memory transaction attributes
1435  * @buf: buffer with the data transferred
1436  * @is_write: indicates the transfer direction
1437  */
1438 MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
1439                              MemTxAttrs attrs, uint8_t *buf,
1440                              int len, bool is_write);
1441 
1442 /**
1443  * address_space_write: write to address space.
1444  *
1445  * Return a MemTxResult indicating whether the operation succeeded
1446  * or failed (eg unassigned memory, device rejected the transaction,
1447  * IOMMU fault).
1448  *
1449  * @as: #AddressSpace to be accessed
1450  * @addr: address within that address space
1451  * @attrs: memory transaction attributes
1452  * @buf: buffer with the data transferred
1453  */
1454 MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
1455                                 MemTxAttrs attrs,
1456                                 const uint8_t *buf, int len);
1457 
1458 /* address_space_ld*: load from an address space
1459  * address_space_st*: store to an address space
1460  *
1461  * These functions perform a load or store of the byte, word,
1462  * longword or quad to the specified address within the AddressSpace.
1463  * The _le suffixed functions treat the data as little endian;
1464  * _be indicates big endian; no suffix indicates "same endianness
1465  * as guest CPU".
1466  *
1467  * The "guest CPU endianness" accessors are deprecated for use outside
1468  * target-* code; devices should be CPU-agnostic and use either the LE
1469  * or the BE accessors.
1470  *
1471  * @as #AddressSpace to be accessed
1472  * @addr: address within that address space
1473  * @val: data value, for stores
1474  * @attrs: memory transaction attributes
1475  * @result: location to write the success/failure of the transaction;
1476  *   if NULL, this information is discarded
1477  */
1478 uint32_t address_space_ldub(AddressSpace *as, hwaddr addr,
1479                             MemTxAttrs attrs, MemTxResult *result);
1480 uint32_t address_space_lduw_le(AddressSpace *as, hwaddr addr,
1481                             MemTxAttrs attrs, MemTxResult *result);
1482 uint32_t address_space_lduw_be(AddressSpace *as, hwaddr addr,
1483                             MemTxAttrs attrs, MemTxResult *result);
1484 uint32_t address_space_ldl_le(AddressSpace *as, hwaddr addr,
1485                             MemTxAttrs attrs, MemTxResult *result);
1486 uint32_t address_space_ldl_be(AddressSpace *as, hwaddr addr,
1487                             MemTxAttrs attrs, MemTxResult *result);
1488 uint64_t address_space_ldq_le(AddressSpace *as, hwaddr addr,
1489                             MemTxAttrs attrs, MemTxResult *result);
1490 uint64_t address_space_ldq_be(AddressSpace *as, hwaddr addr,
1491                             MemTxAttrs attrs, MemTxResult *result);
1492 void address_space_stb(AddressSpace *as, hwaddr addr, uint32_t val,
1493                             MemTxAttrs attrs, MemTxResult *result);
1494 void address_space_stw_le(AddressSpace *as, hwaddr addr, uint32_t val,
1495                             MemTxAttrs attrs, MemTxResult *result);
1496 void address_space_stw_be(AddressSpace *as, hwaddr addr, uint32_t val,
1497                             MemTxAttrs attrs, MemTxResult *result);
1498 void address_space_stl_le(AddressSpace *as, hwaddr addr, uint32_t val,
1499                             MemTxAttrs attrs, MemTxResult *result);
1500 void address_space_stl_be(AddressSpace *as, hwaddr addr, uint32_t val,
1501                             MemTxAttrs attrs, MemTxResult *result);
1502 void address_space_stq_le(AddressSpace *as, hwaddr addr, uint64_t val,
1503                             MemTxAttrs attrs, MemTxResult *result);
1504 void address_space_stq_be(AddressSpace *as, hwaddr addr, uint64_t val,
1505                             MemTxAttrs attrs, MemTxResult *result);
1506 
1507 uint32_t ldub_phys(AddressSpace *as, hwaddr addr);
1508 uint32_t lduw_le_phys(AddressSpace *as, hwaddr addr);
1509 uint32_t lduw_be_phys(AddressSpace *as, hwaddr addr);
1510 uint32_t ldl_le_phys(AddressSpace *as, hwaddr addr);
1511 uint32_t ldl_be_phys(AddressSpace *as, hwaddr addr);
1512 uint64_t ldq_le_phys(AddressSpace *as, hwaddr addr);
1513 uint64_t ldq_be_phys(AddressSpace *as, hwaddr addr);
1514 void stb_phys(AddressSpace *as, hwaddr addr, uint32_t val);
1515 void stw_le_phys(AddressSpace *as, hwaddr addr, uint32_t val);
1516 void stw_be_phys(AddressSpace *as, hwaddr addr, uint32_t val);
1517 void stl_le_phys(AddressSpace *as, hwaddr addr, uint32_t val);
1518 void stl_be_phys(AddressSpace *as, hwaddr addr, uint32_t val);
1519 void stq_le_phys(AddressSpace *as, hwaddr addr, uint64_t val);
1520 void stq_be_phys(AddressSpace *as, hwaddr addr, uint64_t val);
1521 
1522 struct MemoryRegionCache {
1523     hwaddr xlat;
1524     hwaddr len;
1525     AddressSpace *as;
1526 };
1527 
1528 #define MEMORY_REGION_CACHE_INVALID ((MemoryRegionCache) { .as = NULL })
1529 
1530 /* address_space_cache_init: prepare for repeated access to a physical
1531  * memory region
1532  *
1533  * @cache: #MemoryRegionCache to be filled
1534  * @as: #AddressSpace to be accessed
1535  * @addr: address within that address space
1536  * @len: length of buffer
1537  * @is_write: indicates the transfer direction
1538  *
1539  * Will only work with RAM, and may map a subset of the requested range by
1540  * returning a value that is less than @len.  On failure, return a negative
1541  * errno value.
1542  *
1543  * Because it only works with RAM, this function can be used for
1544  * read-modify-write operations.  In this case, is_write should be %true.
1545  *
1546  * Note that addresses passed to the address_space_*_cached functions
1547  * are relative to @addr.
1548  */
1549 int64_t address_space_cache_init(MemoryRegionCache *cache,
1550                                  AddressSpace *as,
1551                                  hwaddr addr,
1552                                  hwaddr len,
1553                                  bool is_write);
1554 
1555 /**
1556  * address_space_cache_invalidate: complete a write to a #MemoryRegionCache
1557  *
1558  * @cache: The #MemoryRegionCache to operate on.
1559  * @addr: The first physical address that was written, relative to the
1560  * address that was passed to @address_space_cache_init.
1561  * @access_len: The number of bytes that were written starting at @addr.
1562  */
1563 void address_space_cache_invalidate(MemoryRegionCache *cache,
1564                                     hwaddr addr,
1565                                     hwaddr access_len);
1566 
1567 /**
1568  * address_space_cache_destroy: free a #MemoryRegionCache
1569  *
1570  * @cache: The #MemoryRegionCache whose memory should be released.
1571  */
1572 void address_space_cache_destroy(MemoryRegionCache *cache);
1573 
1574 /* address_space_ld*_cached: load from a cached #MemoryRegion
1575  * address_space_st*_cached: store into a cached #MemoryRegion
1576  *
1577  * These functions perform a load or store of the byte, word,
1578  * longword or quad to the specified address.  The address is
1579  * a physical address in the AddressSpace, but it must lie within
1580  * a #MemoryRegion that was mapped with address_space_cache_init.
1581  *
1582  * The _le suffixed functions treat the data as little endian;
1583  * _be indicates big endian; no suffix indicates "same endianness
1584  * as guest CPU".
1585  *
1586  * The "guest CPU endianness" accessors are deprecated for use outside
1587  * target-* code; devices should be CPU-agnostic and use either the LE
1588  * or the BE accessors.
1589  *
1590  * @cache: previously initialized #MemoryRegionCache to be accessed
1591  * @addr: address within the address space
1592  * @val: data value, for stores
1593  * @attrs: memory transaction attributes
1594  * @result: location to write the success/failure of the transaction;
1595  *   if NULL, this information is discarded
1596  */
1597 uint32_t address_space_ldub_cached(MemoryRegionCache *cache, hwaddr addr,
1598                             MemTxAttrs attrs, MemTxResult *result);
1599 uint32_t address_space_lduw_le_cached(MemoryRegionCache *cache, hwaddr addr,
1600                             MemTxAttrs attrs, MemTxResult *result);
1601 uint32_t address_space_lduw_be_cached(MemoryRegionCache *cache, hwaddr addr,
1602                             MemTxAttrs attrs, MemTxResult *result);
1603 uint32_t address_space_ldl_le_cached(MemoryRegionCache *cache, hwaddr addr,
1604                             MemTxAttrs attrs, MemTxResult *result);
1605 uint32_t address_space_ldl_be_cached(MemoryRegionCache *cache, hwaddr addr,
1606                             MemTxAttrs attrs, MemTxResult *result);
1607 uint64_t address_space_ldq_le_cached(MemoryRegionCache *cache, hwaddr addr,
1608                             MemTxAttrs attrs, MemTxResult *result);
1609 uint64_t address_space_ldq_be_cached(MemoryRegionCache *cache, hwaddr addr,
1610                             MemTxAttrs attrs, MemTxResult *result);
1611 void address_space_stb_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
1612                             MemTxAttrs attrs, MemTxResult *result);
1613 void address_space_stw_le_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
1614                             MemTxAttrs attrs, MemTxResult *result);
1615 void address_space_stw_be_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
1616                             MemTxAttrs attrs, MemTxResult *result);
1617 void address_space_stl_le_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
1618                             MemTxAttrs attrs, MemTxResult *result);
1619 void address_space_stl_be_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
1620                             MemTxAttrs attrs, MemTxResult *result);
1621 void address_space_stq_le_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val,
1622                             MemTxAttrs attrs, MemTxResult *result);
1623 void address_space_stq_be_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val,
1624                             MemTxAttrs attrs, MemTxResult *result);
1625 
1626 uint32_t ldub_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1627 uint32_t lduw_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1628 uint32_t lduw_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1629 uint32_t ldl_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1630 uint32_t ldl_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1631 uint64_t ldq_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1632 uint64_t ldq_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
1633 void stb_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
1634 void stw_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
1635 void stw_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
1636 void stl_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
1637 void stl_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
1638 void stq_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val);
1639 void stq_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val);
1640 /* address_space_get_iotlb_entry: translate an address into an IOTLB
1641  * entry. Should be called from an RCU critical section.
1642  */
1643 IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
1644                                             bool is_write);
1645 
1646 /* address_space_translate: translate an address range into an address space
1647  * into a MemoryRegion and an address range into that section.  Should be
1648  * called from an RCU critical section, to avoid that the last reference
1649  * to the returned region disappears after address_space_translate returns.
1650  *
1651  * @as: #AddressSpace to be accessed
1652  * @addr: address within that address space
1653  * @xlat: pointer to address within the returned memory region section's
1654  * #MemoryRegion.
1655  * @len: pointer to length
1656  * @is_write: indicates the transfer direction
1657  */
1658 MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
1659                                       hwaddr *xlat, hwaddr *len,
1660                                       bool is_write);
1661 
1662 /* address_space_access_valid: check for validity of accessing an address
1663  * space range
1664  *
1665  * Check whether memory is assigned to the given address space range, and
1666  * access is permitted by any IOMMU regions that are active for the address
1667  * space.
1668  *
1669  * For now, addr and len should be aligned to a page size.  This limitation
1670  * will be lifted in the future.
1671  *
1672  * @as: #AddressSpace to be accessed
1673  * @addr: address within that address space
1674  * @len: length of the area to be checked
1675  * @is_write: indicates the transfer direction
1676  */
1677 bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_write);
1678 
1679 /* address_space_map: map a physical memory region into a host virtual address
1680  *
1681  * May map a subset of the requested range, given by and returned in @plen.
1682  * May return %NULL if resources needed to perform the mapping are exhausted.
1683  * Use only for reads OR writes - not for read-modify-write operations.
1684  * Use cpu_register_map_client() to know when retrying the map operation is
1685  * likely to succeed.
1686  *
1687  * @as: #AddressSpace to be accessed
1688  * @addr: address within that address space
1689  * @plen: pointer to length of buffer; updated on return
1690  * @is_write: indicates the transfer direction
1691  */
1692 void *address_space_map(AddressSpace *as, hwaddr addr,
1693                         hwaddr *plen, bool is_write);
1694 
1695 /* address_space_unmap: Unmaps a memory region previously mapped by address_space_map()
1696  *
1697  * Will also mark the memory as dirty if @is_write == %true.  @access_len gives
1698  * the amount of memory that was actually read or written by the caller.
1699  *
1700  * @as: #AddressSpace used
1701  * @addr: address within that address space
1702  * @len: buffer length as returned by address_space_map()
1703  * @access_len: amount of data actually transferred
1704  * @is_write: indicates the transfer direction
1705  */
1706 void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
1707                          int is_write, hwaddr access_len);
1708 
1709 
1710 /* Internal functions, part of the implementation of address_space_read.  */
1711 MemTxResult address_space_read_continue(AddressSpace *as, hwaddr addr,
1712                                         MemTxAttrs attrs, uint8_t *buf,
1713                                         int len, hwaddr addr1, hwaddr l,
1714 					MemoryRegion *mr);
1715 MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
1716                                     MemTxAttrs attrs, uint8_t *buf, int len);
1717 void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr);
1718 
1719 static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
1720 {
1721     if (is_write) {
1722         return memory_region_is_ram(mr) &&
1723                !mr->readonly && !memory_region_is_ram_device(mr);
1724     } else {
1725         return (memory_region_is_ram(mr) && !memory_region_is_ram_device(mr)) ||
1726                memory_region_is_romd(mr);
1727     }
1728 }
1729 
1730 /**
1731  * address_space_read: read from an address space.
1732  *
1733  * Return a MemTxResult indicating whether the operation succeeded
1734  * or failed (eg unassigned memory, device rejected the transaction,
1735  * IOMMU fault).
1736  *
1737  * @as: #AddressSpace to be accessed
1738  * @addr: address within that address space
1739  * @attrs: memory transaction attributes
1740  * @buf: buffer with the data transferred
1741  */
1742 static inline __attribute__((__always_inline__))
1743 MemTxResult address_space_read(AddressSpace *as, hwaddr addr, MemTxAttrs attrs,
1744                                uint8_t *buf, int len)
1745 {
1746     MemTxResult result = MEMTX_OK;
1747     hwaddr l, addr1;
1748     void *ptr;
1749     MemoryRegion *mr;
1750 
1751     if (__builtin_constant_p(len)) {
1752         if (len) {
1753             rcu_read_lock();
1754             l = len;
1755             mr = address_space_translate(as, addr, &addr1, &l, false);
1756             if (len == l && memory_access_is_direct(mr, false)) {
1757                 ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
1758                 memcpy(buf, ptr, len);
1759             } else {
1760                 result = address_space_read_continue(as, addr, attrs, buf, len,
1761                                                      addr1, l, mr);
1762             }
1763             rcu_read_unlock();
1764         }
1765     } else {
1766         result = address_space_read_full(as, addr, attrs, buf, len);
1767     }
1768     return result;
1769 }
1770 
1771 /**
1772  * address_space_read_cached: read from a cached RAM region
1773  *
1774  * @cache: Cached region to be addressed
1775  * @addr: address relative to the base of the RAM region
1776  * @buf: buffer with the data transferred
1777  * @len: length of the data transferred
1778  */
1779 static inline void
1780 address_space_read_cached(MemoryRegionCache *cache, hwaddr addr,
1781                           void *buf, int len)
1782 {
1783     assert(addr < cache->len && len <= cache->len - addr);
1784     address_space_read(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len);
1785 }
1786 
1787 /**
1788  * address_space_write_cached: write to a cached RAM region
1789  *
1790  * @cache: Cached region to be addressed
1791  * @addr: address relative to the base of the RAM region
1792  * @buf: buffer with the data transferred
1793  * @len: length of the data transferred
1794  */
1795 static inline void
1796 address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
1797                            void *buf, int len)
1798 {
1799     assert(addr < cache->len && len <= cache->len - addr);
1800     address_space_write(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len);
1801 }
1802 
1803 #endif
1804 
1805 #endif
1806