softmmu/memory_mapping.c - third_party/qemu - Git at Google

 /*
  * QEMU memory mapping
  *
  * Copyright Fujitsu, Corp. 2011, 2012
  *
  * Authors:
  *     Wen Congyang <wency@cn.fujitsu.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  *
  */

 #include "qemu/osdep.h"
 #include "qapi/error.h"

 #include "sysemu/memory_mapping.h"
 #include "exec/memory.h"
 #include "exec/address-spaces.h"
 #include "hw/core/cpu.h"

 //#define DEBUG_GUEST_PHYS_REGION_ADD

 static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
                                                    MemoryMapping *mapping)
 {
     MemoryMapping *p;

     QTAILQ_FOREACH(p, &list->head, next) {
         if (p->phys_addr >= mapping->phys_addr) {
             QTAILQ_INSERT_BEFORE(p, mapping, next);
             return;
         }
     }
     QTAILQ_INSERT_TAIL(&list->head, mapping, next);
 }

 static void create_new_memory_mapping(MemoryMappingList *list,
                                       hwaddr phys_addr,
                                       hwaddr virt_addr,
                                       ram_addr_t length)
 {
     MemoryMapping *memory_mapping;

     memory_mapping = g_new(MemoryMapping, 1);
     memory_mapping->phys_addr = phys_addr;
     memory_mapping->virt_addr = virt_addr;
     memory_mapping->length = length;
     list->last_mapping = memory_mapping;
     list->num++;
     memory_mapping_list_add_mapping_sorted(list, memory_mapping);
 }

 static inline bool mapping_contiguous(MemoryMapping *map,
                                       hwaddr phys_addr,
                                       hwaddr virt_addr)
 {
     return phys_addr == map->phys_addr + map->length &&
            virt_addr == map->virt_addr + map->length;
 }

 /*
  * [map->phys_addr, map->phys_addr + map->length) and
  * [phys_addr, phys_addr + length) have intersection?
  */
 static inline bool mapping_have_same_region(MemoryMapping *map,
                                             hwaddr phys_addr,
                                             ram_addr_t length)
 {
     return !(phys_addr + length < map->phys_addr ||
              phys_addr >= map->phys_addr + map->length);
 }

 /*
  * [map->phys_addr, map->phys_addr + map->length) and
  * [phys_addr, phys_addr + length) have intersection. The virtual address in the
  * intersection are the same?
  */
 static inline bool mapping_conflict(MemoryMapping *map,
                                     hwaddr phys_addr,
                                     hwaddr virt_addr)
 {
     return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
 }

 /*
  * [map->virt_addr, map->virt_addr + map->length) and
  * [virt_addr, virt_addr + length) have intersection. And the physical address
  * in the intersection are the same.
  */
 static inline void mapping_merge(MemoryMapping *map,
                                  hwaddr virt_addr,
                                  ram_addr_t length)
 {
     if (virt_addr < map->virt_addr) {
         map->length += map->virt_addr - virt_addr;
         map->virt_addr = virt_addr;
     }

     if ((virt_addr + length) >
         (map->virt_addr + map->length)) {
         map->length = virt_addr + length - map->virt_addr;
     }
 }

 void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
                                           hwaddr phys_addr,
                                           hwaddr virt_addr,
                                           ram_addr_t length)
 {
     MemoryMapping *memory_mapping, *last_mapping;

     if (QTAILQ_EMPTY(&list->head)) {
         create_new_memory_mapping(list, phys_addr, virt_addr, length);
         return;
     }

     last_mapping = list->last_mapping;
     if (last_mapping) {
         if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
             last_mapping->length += length;
             return;
         }
     }

     QTAILQ_FOREACH(memory_mapping, &list->head, next) {
         if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
             memory_mapping->length += length;
             list->last_mapping = memory_mapping;
             return;
         }

         if (phys_addr + length < memory_mapping->phys_addr) {
             /* create a new region before memory_mapping */
             break;
         }

         if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
             if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
                 continue;
             }

             /* merge this region into memory_mapping */
             mapping_merge(memory_mapping, virt_addr, length);
             list->last_mapping = memory_mapping;
             return;
         }
     }

     /* this region can not be merged into any existed memory mapping. */
     create_new_memory_mapping(list, phys_addr, virt_addr, length);
 }

 void memory_mapping_list_free(MemoryMappingList *list)
 {
     MemoryMapping *p, *q;

     QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
         QTAILQ_REMOVE(&list->head, p, next);
         g_free(p);
     }

     list->num = 0;
     list->last_mapping = NULL;
 }

 void memory_mapping_list_init(MemoryMappingList *list)
 {
     list->num = 0;
     list->last_mapping = NULL;
     QTAILQ_INIT(&list->head);
 }

 void guest_phys_blocks_free(GuestPhysBlockList *list)
 {
     GuestPhysBlock *p, *q;

     QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
         QTAILQ_REMOVE(&list->head, p, next);
         memory_region_unref(p->mr);
         g_free(p);
     }
     list->num = 0;
 }

 void guest_phys_blocks_init(GuestPhysBlockList *list)
 {
     list->num = 0;
     QTAILQ_INIT(&list->head);
 }

 typedef struct GuestPhysListener {
     GuestPhysBlockList *list;
     MemoryListener listener;
 } GuestPhysListener;

 static void guest_phys_block_add_section(GuestPhysListener *g,
                                          MemoryRegionSection *section)
 {
     const hwaddr target_start = section->offset_within_address_space;
     const hwaddr target_end = target_start + int128_get64(section->size);
     uint8_t *host_addr = memory_region_get_ram_ptr(section->mr) +
                          section->offset_within_region;
     GuestPhysBlock *predecessor = NULL;

     /* find continuity in guest physical address space */
     if (!QTAILQ_EMPTY(&g->list->head)) {
         hwaddr predecessor_size;

         predecessor = QTAILQ_LAST(&g->list->head);
         predecessor_size = predecessor->target_end - predecessor->target_start;

         /* the memory API guarantees monotonically increasing traversal */
         g_assert(predecessor->target_end <= target_start);

         /* we want continuity in both guest-physical and host-virtual memory */
         if (predecessor->target_end < target_start ||
             predecessor->host_addr + predecessor_size != host_addr ||
             predecessor->mr != section->mr) {
             predecessor = NULL;
         }
     }

     if (predecessor == NULL) {
         /* isolated mapping, allocate it and add it to the list */
         GuestPhysBlock *block = g_malloc0(sizeof *block);

         block->target_start = target_start;
         block->target_end   = target_end;
         block->host_addr    = host_addr;
         block->mr           = section->mr;
         memory_region_ref(section->mr);

         QTAILQ_INSERT_TAIL(&g->list->head, block, next);
         ++g->list->num;
     } else {
         /* expand predecessor until @target_end; predecessor's start doesn't
          * change
          */
         predecessor->target_end = target_end;
     }

 #ifdef DEBUG_GUEST_PHYS_REGION_ADD
     fprintf(stderr, "%s: target_start=" TARGET_FMT_plx " target_end="
             TARGET_FMT_plx ": %s (count: %u)\n", __func__, target_start,
             target_end, predecessor ? "joined" : "added", g->list->num);
 #endif
 }

 static int guest_phys_ram_populate_cb(MemoryRegionSection *section,
                                       void *opaque)
 {
     GuestPhysListener *g = opaque;

     guest_phys_block_add_section(g, section);
     return 0;
 }

 static void guest_phys_blocks_region_add(MemoryListener *listener,
                                          MemoryRegionSection *section)
 {
     GuestPhysListener *g = container_of(listener, GuestPhysListener, listener);

     /* we only care about RAM */
     if (!memory_region_is_ram(section->mr) ||
         memory_region_is_ram_device(section->mr) ||
         memory_region_is_nonvolatile(section->mr)) {
         return;
     }

     /* for special sparse regions, only add populated parts */
     if (memory_region_has_ram_discard_manager(section->mr)) {
         RamDiscardManager *rdm;

         rdm = memory_region_get_ram_discard_manager(section->mr);
         ram_discard_manager_replay_populated(rdm, section,
                                              guest_phys_ram_populate_cb, g);
         return;
     }

     guest_phys_block_add_section(g, section);
 }

 void guest_phys_blocks_append(GuestPhysBlockList *list)
 {
     GuestPhysListener g = { 0 };

     g.list = list;
     g.listener.region_add = &guest_phys_blocks_region_add;
     memory_listener_register(&g.listener, &address_space_memory);
     memory_listener_unregister(&g.listener);
 }

 static CPUState *find_paging_enabled_cpu(CPUState *start_cpu)
 {
     CPUState *cpu;

     CPU_FOREACH(cpu) {
         if (cpu_paging_enabled(cpu)) {
             return cpu;
         }
     }

     return NULL;
 }

 void qemu_get_guest_memory_mapping(MemoryMappingList *list,
                                    const GuestPhysBlockList *guest_phys_blocks,
                                    Error **errp)
 {
     CPUState *cpu, *first_paging_enabled_cpu;
     GuestPhysBlock *block;
     ram_addr_t offset, length;

     first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
     if (first_paging_enabled_cpu) {
         for (cpu = first_paging_enabled_cpu; cpu != NULL;
              cpu = CPU_NEXT(cpu)) {
             Error *err = NULL;
             cpu_get_memory_mapping(cpu, list, &err);
             if (err) {
                 error_propagate(errp, err);
                 return;
             }
         }
         return;
     }

     /*
      * If the guest doesn't use paging, the virtual address is equal to physical
      * address.
      */
     QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
         offset = block->target_start;
         length = block->target_end - block->target_start;
         create_new_memory_mapping(list, offset, offset, length);
     }
 }

 void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list,
                                    const GuestPhysBlockList *guest_phys_blocks)
 {
     GuestPhysBlock *block;

     QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
         create_new_memory_mapping(list, block->target_start, 0,
                                   block->target_end - block->target_start);
     }
 }

 void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
                            int64_t length)
 {
     MemoryMapping *cur, *next;

     QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
         if (cur->phys_addr >= begin + length ||
             cur->phys_addr + cur->length <= begin) {
             QTAILQ_REMOVE(&list->head, cur, next);
             g_free(cur);
             list->num--;
             continue;
         }

         if (cur->phys_addr < begin) {
             cur->length -= begin - cur->phys_addr;
             if (cur->virt_addr) {
                 cur->virt_addr += begin - cur->phys_addr;
             }
             cur->phys_addr = begin;
         }

         if (cur->phys_addr + cur->length > begin + length) {
             cur->length -= cur->phys_addr + cur->length - begin - length;
         }
     }
 }
	/*
	* QEMU memory mapping
	*
	* Copyright Fujitsu, Corp. 2011, 2012
	*
	* Authors:
	* Wen Congyang <wency@cn.fujitsu.com>
	*
	* This work is licensed under the terms of the GNU GPL, version 2 or later.
	* See the COPYING file in the top-level directory.
	*
	*/

	#include "qemu/osdep.h"
	#include "qapi/error.h"

	#include "sysemu/memory_mapping.h"
	#include "exec/memory.h"
	#include "exec/address-spaces.h"
	#include "hw/core/cpu.h"

	//#define DEBUG_GUEST_PHYS_REGION_ADD

	static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
	MemoryMapping *mapping)
	{
	MemoryMapping *p;

	QTAILQ_FOREACH(p, &list->head, next) {
	if (p->phys_addr >= mapping->phys_addr) {
	QTAILQ_INSERT_BEFORE(p, mapping, next);
	return;
	}
	}
	QTAILQ_INSERT_TAIL(&list->head, mapping, next);
	}

	static void create_new_memory_mapping(MemoryMappingList *list,
	hwaddr phys_addr,
	hwaddr virt_addr,
	ram_addr_t length)
	{
	MemoryMapping *memory_mapping;

	memory_mapping = g_new(MemoryMapping, 1);
	memory_mapping->phys_addr = phys_addr;
	memory_mapping->virt_addr = virt_addr;
	memory_mapping->length = length;
	list->last_mapping = memory_mapping;
	list->num++;
	memory_mapping_list_add_mapping_sorted(list, memory_mapping);
	}

	static inline bool mapping_contiguous(MemoryMapping *map,
	hwaddr phys_addr,
	hwaddr virt_addr)
	{
	return phys_addr == map->phys_addr + map->length &&
	virt_addr == map->virt_addr + map->length;
	}

	/*
	* [map->phys_addr, map->phys_addr + map->length) and
	* [phys_addr, phys_addr + length) have intersection?
	*/
	static inline bool mapping_have_same_region(MemoryMapping *map,
	hwaddr phys_addr,
	ram_addr_t length)
	{
	return !(phys_addr + length < map->phys_addr \|\|
	phys_addr >= map->phys_addr + map->length);
	}

	/*
	* [map->phys_addr, map->phys_addr + map->length) and
	* [phys_addr, phys_addr + length) have intersection. The virtual address in the
	* intersection are the same?
	*/
	static inline bool mapping_conflict(MemoryMapping *map,
	hwaddr phys_addr,
	hwaddr virt_addr)
	{
	return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
	}

	/*
	* [map->virt_addr, map->virt_addr + map->length) and
	* [virt_addr, virt_addr + length) have intersection. And the physical address
	* in the intersection are the same.
	*/
	static inline void mapping_merge(MemoryMapping *map,
	hwaddr virt_addr,
	ram_addr_t length)
	{
	if (virt_addr < map->virt_addr) {
	map->length += map->virt_addr - virt_addr;
	map->virt_addr = virt_addr;
	}

	if ((virt_addr + length) >
	(map->virt_addr + map->length)) {
	map->length = virt_addr + length - map->virt_addr;
	}
	}

	void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
	hwaddr phys_addr,
	hwaddr virt_addr,
	ram_addr_t length)
	{
	MemoryMapping memory_mapping, last_mapping;

	if (QTAILQ_EMPTY(&list->head)) {
	create_new_memory_mapping(list, phys_addr, virt_addr, length);
	return;
	}

	last_mapping = list->last_mapping;
	if (last_mapping) {
	if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
	last_mapping->length += length;
	return;
	}
	}

	QTAILQ_FOREACH(memory_mapping, &list->head, next) {
	if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
	memory_mapping->length += length;
	list->last_mapping = memory_mapping;
	return;
	}

	if (phys_addr + length < memory_mapping->phys_addr) {
	/* create a new region before memory_mapping */
	break;
	}

	if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
	if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
	continue;
	}

	/* merge this region into memory_mapping */
	mapping_merge(memory_mapping, virt_addr, length);
	list->last_mapping = memory_mapping;
	return;
	}
	}

	/* this region can not be merged into any existed memory mapping. */
	create_new_memory_mapping(list, phys_addr, virt_addr, length);
	}

	void memory_mapping_list_free(MemoryMappingList *list)
	{
	MemoryMapping p, q;

	QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
	QTAILQ_REMOVE(&list->head, p, next);
	g_free(p);
	}

	list->num = 0;
	list->last_mapping = NULL;
	}

	void memory_mapping_list_init(MemoryMappingList *list)
	{
	list->num = 0;
	list->last_mapping = NULL;
	QTAILQ_INIT(&list->head);
	}

	void guest_phys_blocks_free(GuestPhysBlockList *list)
	{
	GuestPhysBlock p, q;

	QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
	QTAILQ_REMOVE(&list->head, p, next);
	memory_region_unref(p->mr);
	g_free(p);
	}
	list->num = 0;
	}

	void guest_phys_blocks_init(GuestPhysBlockList *list)
	{
	list->num = 0;
	QTAILQ_INIT(&list->head);
	}

	typedef struct GuestPhysListener {
	GuestPhysBlockList *list;
	MemoryListener listener;
	} GuestPhysListener;

	static void guest_phys_block_add_section(GuestPhysListener *g,
	MemoryRegionSection *section)
	{
	const hwaddr target_start = section->offset_within_address_space;
	const hwaddr target_end = target_start + int128_get64(section->size);
	uint8_t *host_addr = memory_region_get_ram_ptr(section->mr) +
	section->offset_within_region;
	GuestPhysBlock *predecessor = NULL;

	/* find continuity in guest physical address space */
	if (!QTAILQ_EMPTY(&g->list->head)) {
	hwaddr predecessor_size;

	predecessor = QTAILQ_LAST(&g->list->head);
	predecessor_size = predecessor->target_end - predecessor->target_start;

	/* the memory API guarantees monotonically increasing traversal */
	g_assert(predecessor->target_end <= target_start);

	/* we want continuity in both guest-physical and host-virtual memory */
	if (predecessor->target_end < target_start \|\|
	predecessor->host_addr + predecessor_size != host_addr \|\|
	predecessor->mr != section->mr) {
	predecessor = NULL;
	}
	}

	if (predecessor == NULL) {
	/* isolated mapping, allocate it and add it to the list */
	GuestPhysBlock block = g_malloc0(sizeof block);

	block->target_start = target_start;
	block->target_end = target_end;
	block->host_addr = host_addr;
	block->mr = section->mr;
	memory_region_ref(section->mr);

	QTAILQ_INSERT_TAIL(&g->list->head, block, next);
	++g->list->num;
	} else {
	/* expand predecessor until @target_end; predecessor's start doesn't
	* change
	*/
	predecessor->target_end = target_end;
	}

	#ifdef DEBUG_GUEST_PHYS_REGION_ADD
	fprintf(stderr, "%s: target_start=" TARGET_FMT_plx " target_end="
	TARGET_FMT_plx ": %s (count: %u)\n", __func__, target_start,
	target_end, predecessor ? "joined" : "added", g->list->num);
	#endif
	}

	static int guest_phys_ram_populate_cb(MemoryRegionSection *section,
	void *opaque)
	{
	GuestPhysListener *g = opaque;

	guest_phys_block_add_section(g, section);
	return 0;
	}

	static void guest_phys_blocks_region_add(MemoryListener *listener,
	MemoryRegionSection *section)
	{
	GuestPhysListener *g = container_of(listener, GuestPhysListener, listener);

	/* we only care about RAM */
	if (!memory_region_is_ram(section->mr) \|\|
	memory_region_is_ram_device(section->mr) \|\|
	memory_region_is_nonvolatile(section->mr)) {
	return;
	}

	/* for special sparse regions, only add populated parts */
	if (memory_region_has_ram_discard_manager(section->mr)) {
	RamDiscardManager *rdm;

	rdm = memory_region_get_ram_discard_manager(section->mr);
	ram_discard_manager_replay_populated(rdm, section,
	guest_phys_ram_populate_cb, g);
	return;
	}

	guest_phys_block_add_section(g, section);
	}

	void guest_phys_blocks_append(GuestPhysBlockList *list)
	{
	GuestPhysListener g = { 0 };

	g.list = list;
	g.listener.region_add = &guest_phys_blocks_region_add;
	memory_listener_register(&g.listener, &address_space_memory);
	memory_listener_unregister(&g.listener);
	}

	static CPUState find_paging_enabled_cpu(CPUState start_cpu)
	{
	CPUState *cpu;

	CPU_FOREACH(cpu) {
	if (cpu_paging_enabled(cpu)) {
	return cpu;
	}
	}

	return NULL;
	}

	void qemu_get_guest_memory_mapping(MemoryMappingList *list,
	const GuestPhysBlockList *guest_phys_blocks,
	Error **errp)
	{
	CPUState cpu, first_paging_enabled_cpu;
	GuestPhysBlock *block;
	ram_addr_t offset, length;

	first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
	if (first_paging_enabled_cpu) {
	for (cpu = first_paging_enabled_cpu; cpu != NULL;
	cpu = CPU_NEXT(cpu)) {
	Error *err = NULL;
	cpu_get_memory_mapping(cpu, list, &err);
	if (err) {
	error_propagate(errp, err);
	return;
	}
	}
	return;
	}

	/*
	* If the guest doesn't use paging, the virtual address is equal to physical
	* address.
	*/
	QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
	offset = block->target_start;
	length = block->target_end - block->target_start;
	create_new_memory_mapping(list, offset, offset, length);
	}
	}

	void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list,
	const GuestPhysBlockList *guest_phys_blocks)
	{
	GuestPhysBlock *block;

	QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
	create_new_memory_mapping(list, block->target_start, 0,
	block->target_end - block->target_start);
	}
	}

	void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
	int64_t length)
	{
	MemoryMapping cur, next;

	QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
	if (cur->phys_addr >= begin + length \|\|
	cur->phys_addr + cur->length <= begin) {
	QTAILQ_REMOVE(&list->head, cur, next);
	g_free(cur);
	list->num--;
	continue;
	}

	if (cur->phys_addr < begin) {
	cur->length -= begin - cur->phys_addr;
	if (cur->virt_addr) {
	cur->virt_addr += begin - cur->phys_addr;
	}
	cur->phys_addr = begin;
	}

	if (cur->phys_addr + cur->length > begin + length) {
	cur->length -= cur->phys_addr + cur->length - begin - length;
	}
	}
	}