qemu/include/exec/memory.h

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/*
* Physical memory management API
*
* Copyright 2011 Red Hat, Inc. and/or its affiliates
*
* Authors:
* Avi Kivity <avi@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef MEMORY_H
#define MEMORY_H
#ifndef CONFIG_USER_ONLY
#include "exec/cpu-common.h"
#include "exec/hwaddr.h"
#include "exec/memattrs.h"
#include "exec/ramlist.h"
#include "qemu/queue.h"
#include "qemu/int128.h"
#include "qemu/notify.h"
#include "qom/object.h"
#include "qemu/rcu.h"
#include "hw/qdev-core.h"
#define RAM_ADDR_INVALID (~(ram_addr_t)0)
#define MAX_PHYS_ADDR_SPACE_BITS 62
#define MAX_PHYS_ADDR (((hwaddr)1 << MAX_PHYS_ADDR_SPACE_BITS) - 1)
#define TYPE_MEMORY_REGION "qemu:memory-region"
#define MEMORY_REGION(obj) \
OBJECT_CHECK(MemoryRegion, (obj), TYPE_MEMORY_REGION)
#define TYPE_IOMMU_MEMORY_REGION "qemu:iommu-memory-region"
#define IOMMU_MEMORY_REGION(obj) \
OBJECT_CHECK(IOMMUMemoryRegion, (obj), TYPE_IOMMU_MEMORY_REGION)
#define IOMMU_MEMORY_REGION_CLASS(klass) \
OBJECT_CLASS_CHECK(IOMMUMemoryRegionClass, (klass), \
TYPE_IOMMU_MEMORY_REGION)
#define IOMMU_MEMORY_REGION_GET_CLASS(obj) \
OBJECT_GET_CLASS(IOMMUMemoryRegionClass, (obj), \
TYPE_IOMMU_MEMORY_REGION)
typedef struct MemoryRegionOps MemoryRegionOps;
typedef struct MemoryRegionMmio MemoryRegionMmio;
struct MemoryRegionMmio {
CPUReadMemoryFunc *read[3];
CPUWriteMemoryFunc *write[3];
};
typedef struct IOMMUTLBEntry IOMMUTLBEntry;
/* See address_space_translate: bit 0 is read, bit 1 is write. */
typedef enum {
IOMMU_NONE = 0,
IOMMU_RO = 1,
IOMMU_WO = 2,
IOMMU_RW = 3,
} IOMMUAccessFlags;
#define IOMMU_ACCESS_FLAG(r, w) (((r) ? IOMMU_RO : 0) | ((w) ? IOMMU_WO : 0))
struct IOMMUTLBEntry {
AddressSpace *target_as;
hwaddr iova;
hwaddr translated_addr;
hwaddr addr_mask; /* 0xfff = 4k translation */
IOMMUAccessFlags perm;
};
/*
* Bitmap for different IOMMUNotifier capabilities. Each notifier can
* register with one or multiple IOMMU Notifier capability bit(s).
*/
typedef enum {
IOMMU_NOTIFIER_NONE = 0,
/* Notify cache invalidations */
IOMMU_NOTIFIER_UNMAP = 0x1,
/* Notify entry changes (newly created entries) */
IOMMU_NOTIFIER_MAP = 0x2,
} IOMMUNotifierFlag;
#define IOMMU_NOTIFIER_ALL (IOMMU_NOTIFIER_MAP | IOMMU_NOTIFIER_UNMAP)
struct IOMMUNotifier;
typedef void (*IOMMUNotify)(struct IOMMUNotifier *notifier,
IOMMUTLBEntry *data);
struct IOMMUNotifier {
IOMMUNotify notify;
IOMMUNotifierFlag notifier_flags;
/* Notify for address space range start <= addr <= end */
hwaddr start;
hwaddr end;
QLIST_ENTRY(IOMMUNotifier) node;
};
typedef struct IOMMUNotifier IOMMUNotifier;
static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
IOMMUNotifierFlag flags,
hwaddr start, hwaddr end)
{
n->notify = fn;
n->notifier_flags = flags;
n->start = start;
n->end = end;
}
/*
* Memory region callbacks
*/
struct MemoryRegionOps {
/* Read from the memory region. @addr is relative to @mr; @size is
* in bytes. */
uint64_t (*read)(void *opaque,
hwaddr addr,
unsigned size);
/* Write to the memory region. @addr is relative to @mr; @size is
* in bytes. */
void (*write)(void *opaque,
hwaddr addr,
uint64_t data,
unsigned size);
MemTxResult (*read_with_attrs)(void *opaque,
hwaddr addr,
uint64_t *data,
unsigned size,
MemTxAttrs attrs);
MemTxResult (*write_with_attrs)(void *opaque,
hwaddr addr,
uint64_t data,
unsigned size,
MemTxAttrs attrs);
/* Instruction execution pre-callback:
* @addr is the address of the access relative to the @mr.
* @size is the size of the area returned by the callback.
* @offset is the location of the pointer inside @mr.
*
* Returns a pointer to a location which contains guest code.
*/
void *(*request_ptr)(void *opaque, hwaddr addr, unsigned *size,
unsigned *offset);
enum device_endian endianness;
/* Guest-visible constraints: */
struct {
/* If nonzero, specify bounds on access sizes beyond which a machine
* check is thrown.
*/
unsigned min_access_size;
unsigned max_access_size;
/* If true, unaligned accesses are supported. Otherwise unaligned
* accesses throw machine checks.
*/
bool unaligned;
/*
* If present, and returns #false, the transaction is not accepted
* by the device (and results in machine dependent behaviour such
* as a machine check exception).
*/
bool (*accepts)(void *opaque, hwaddr addr,
unsigned size, bool is_write);
} valid;
/* Internal implementation constraints: */
struct {
/* If nonzero, specifies the minimum size implemented. Smaller sizes
* will be rounded upwards and a partial result will be returned.
*/
unsigned min_access_size;
/* If nonzero, specifies the maximum size implemented. Larger sizes
* will be done as a series of accesses with smaller sizes.
*/
unsigned max_access_size;
/* If true, unaligned accesses are supported. Otherwise all accesses
* are converted to (possibly multiple) naturally aligned accesses.
*/
bool unaligned;
} impl;
/* If .read and .write are not present, old_mmio may be used for
* backwards compatibility with old mmio registration
*/
const MemoryRegionMmio old_mmio;
};
enum IOMMUMemoryRegionAttr {
IOMMU_ATTR_SPAPR_TCE_FD
};
typedef struct IOMMUMemoryRegionClass {
/* private */
struct DeviceClass parent_class;
/*
* Return a TLB entry that contains a given address. Flag should
* be the access permission of this translation operation. We can
* set flag to IOMMU_NONE to mean that we don't need any
* read/write permission checks, like, when for region replay.
*/
IOMMUTLBEntry (*translate)(IOMMUMemoryRegion *iommu, hwaddr addr,
IOMMUAccessFlags flag);
/* Returns minimum supported page size */
uint64_t (*get_min_page_size)(IOMMUMemoryRegion *iommu);
/* Called when IOMMU Notifier flag changed */
void (*notify_flag_changed)(IOMMUMemoryRegion *iommu,
IOMMUNotifierFlag old_flags,
IOMMUNotifierFlag new_flags);
/* Set this up to provide customized IOMMU replay function */
void (*replay)(IOMMUMemoryRegion *iommu, IOMMUNotifier *notifier);
/* Get IOMMU misc attributes */
int (*get_attr)(IOMMUMemoryRegion *iommu, enum IOMMUMemoryRegionAttr,
void *data);
} IOMMUMemoryRegionClass;
typedef struct CoalescedMemoryRange CoalescedMemoryRange;
typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
struct MemoryRegion {
Object parent_obj;
/* All fields are private - violators will be prosecuted */
/* The following fields should fit in a cache line */
bool romd_mode;
bool ram;
bool subpage;
bool readonly; /* For RAM regions */
bool rom_device;
bool flush_coalesced_mmio;
bool global_locking;
uint8_t dirty_log_mask;
bool is_iommu;
RAMBlock *ram_block;
Object *owner;
const MemoryRegionOps *ops;
void *opaque;
MemoryRegion *container;
Int128 size;
hwaddr addr;
void (*destructor)(MemoryRegion *mr);
uint64_t align;
bool terminates;
bool ram_device;
bool enabled;
bool warning_printed; /* For reservations */
uint8_t vga_logging_count;
MemoryRegion *alias;
hwaddr alias_offset;
int32_t priority;
QTAILQ_HEAD(subregions, MemoryRegion) subregions;
QTAILQ_ENTRY(MemoryRegion) subregions_link;
QTAILQ_HEAD(coalesced_ranges, CoalescedMemoryRange) coalesced;
const char *name;
unsigned ioeventfd_nb;
MemoryRegionIoeventfd *ioeventfds;
};
struct IOMMUMemoryRegion {
MemoryRegion parent_obj;
QLIST_HEAD(, IOMMUNotifier) iommu_notify;
IOMMUNotifierFlag iommu_notify_flags;
};
#define IOMMU_NOTIFIER_FOREACH(n, mr) \
QLIST_FOREACH((n), &(mr)->iommu_notify, node)
/**
* MemoryListener: callbacks structure for updates to the physical memory map
*
* Allows a component to adjust to changes in the guest-visible memory map.
* Use with memory_listener_register() and memory_listener_unregister().
*/
struct MemoryListener {
void (*begin)(MemoryListener *listener);
void (*commit)(MemoryListener *listener);
void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
void (*log_start)(MemoryListener *listener, MemoryRegionSection *section,
int old, int new);
void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section,
int old, int new);
void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);
void (*log_global_start)(MemoryListener *listener);
void (*log_global_stop)(MemoryListener *listener);
void (*eventfd_add)(MemoryListener *listener, MemoryRegionSection *section,
bool match_data, uint64_t data, EventNotifier *e);
void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
bool match_data, uint64_t data, EventNotifier *e);
void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
hwaddr addr, hwaddr len);
void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
hwaddr addr, hwaddr len);
/* Lower = earlier (during add), later (during del) */
unsigned priority;
AddressSpace *address_space;
QTAILQ_ENTRY(MemoryListener) link;
QTAILQ_ENTRY(MemoryListener) link_as;
};
/**
* AddressSpace: describes a mapping of addresses to #MemoryRegion objects
*/
struct AddressSpace {
/* All fields are private. */
struct rcu_head rcu;
char *name;
MemoryRegion *root;
/* Accessed via RCU. */
struct FlatView *current_map;
int ioeventfd_nb;
struct MemoryRegionIoeventfd *ioeventfds;
QTAILQ_HEAD(memory_listeners_as, MemoryListener) listeners;
QTAILQ_ENTRY(AddressSpace) address_spaces_link;
};
typedef struct AddressSpaceDispatch AddressSpaceDispatch;
typedef struct FlatRange FlatRange;
/* Flattened global view of current active memory hierarchy. Kept in sorted
* order.
*/
struct FlatView {
struct rcu_head rcu;
unsigned ref;
FlatRange *ranges;
unsigned nr;
unsigned nr_allocated;
struct AddressSpaceDispatch *dispatch;
MemoryRegion *root;
};
static inline FlatView *address_space_to_flatview(AddressSpace *as)
{
return atomic_rcu_read(&as->current_map);
}
/**
* MemoryRegionSection: describes a fragment of a #MemoryRegion
*
* @mr: the region, or %NULL if empty
* @fv: the flat view of the address space the region is mapped in
* @offset_within_region: the beginning of the section, relative to @mr's start
* @size: the size of the section; will not exceed @mr's boundaries
* @offset_within_address_space: the address of the first byte of the section
* relative to the region's address space
* @readonly: writes to this section are ignored
*/
struct MemoryRegionSection {
MemoryRegion *mr;
FlatView *fv;
hwaddr offset_within_region;
Int128 size;
hwaddr offset_within_address_space;
bool readonly;
};
/**
* memory_region_init: Initialize a memory region
*
* The region typically acts as a container for other memory regions. Use
* memory_region_add_subregion() to add subregions.
*
* @mr: the #MemoryRegion to be initialized
* @owner: the object that tracks the region's reference count
* @name: used for debugging; not visible to the user or ABI
* @size: size of the region; any subregions beyond this size will be clipped
*/
void memory_region_init(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size);
/**
* memory_region_ref: Add 1 to a memory region's reference count
*
* Whenever memory regions are accessed outside the BQL, they need to be
* preserved against hot-unplug. MemoryRegions actually do not have their
* own reference count; they piggyback on a QOM object, their "owner".
* This function adds a reference to the owner.
*
* All MemoryRegions must have an owner if they can disappear, even if the
* device they belong to operates exclusively under the BQL. This is because
* the region could be returned at any time by memory_region_find, and this
* is usually under guest control.
*
* @mr: the #MemoryRegion
*/
void memory_region_ref(MemoryRegion *mr);
/**
* memory_region_unref: Remove 1 to a memory region's reference count
*
* Whenever memory regions are accessed outside the BQL, they need to be
* preserved against hot-unplug. MemoryRegions actually do not have their
* own reference count; they piggyback on a QOM object, their "owner".
* This function removes a reference to the owner and possibly destroys it.
*
* @mr: the #MemoryRegion
*/
void memory_region_unref(MemoryRegion *mr);
/**
* memory_region_init_io: Initialize an I/O memory region.
*
* Accesses into the region will cause the callbacks in @ops to be called.
* if @size is nonzero, subregions will be clipped to @size.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @ops: a structure containing read and write callbacks to be used when
* I/O is performed on the region.
* @opaque: passed to the read and write callbacks of the @ops structure.
* @name: used for debugging; not visible to the user or ABI
* @size: size of the region.
*/
void memory_region_init_io(MemoryRegion *mr,
struct Object *owner,
const MemoryRegionOps *ops,
void *opaque,
const char *name,
uint64_t size);
/**
* memory_region_init_ram_nomigrate: Initialize RAM memory region. Accesses
* into the region will modify memory
* directly.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
*/
void memory_region_init_ram_nomigrate(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_ram_shared_nomigrate: Initialize RAM memory region.
* Accesses into the region will
* modify memory directly.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @share: allow remapping RAM to different addresses
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function is similar to memory_region_init_ram_nomigrate.
* The only difference is part of the RAM region can be remapped.
*/
void memory_region_init_ram_shared_nomigrate(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
bool share,
Error **errp);
/**
* memory_region_init_resizeable_ram: Initialize memory region with resizeable
* RAM. Accesses into the region will
* modify memory directly. Only an initial
* portion of this RAM is actually used.
* The used size can change across reboots.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: used size of the region.
* @max_size: max size of the region.
* @resized: callback to notify owner about used size change.
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
*/
void memory_region_init_resizeable_ram(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
uint64_t max_size,
void (*resized)(const char*,
uint64_t length,
void *host),
Error **errp);
#ifdef __linux__
/**
* memory_region_init_ram_from_file: Initialize RAM memory region with a
* mmap-ed backend.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @align: alignment of the region base address; if 0, the default alignment
* (getpagesize()) will be used.
* @share: %true if memory must be mmaped with the MAP_SHARED flag
* @path: the path in which to allocate the RAM.
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
*/
void memory_region_init_ram_from_file(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
uint64_t align,
bool share,
const char *path,
Error **errp);
/**
* memory_region_init_ram_from_fd: Initialize RAM memory region with a
* mmap-ed backend.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: the name of the region.
* @size: size of the region.
* @share: %true if memory must be mmaped with the MAP_SHARED flag
* @fd: the fd to mmap.
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
*/
void memory_region_init_ram_from_fd(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
bool share,
int fd,
Error **errp);
#endif
/**
* memory_region_init_ram_ptr: Initialize RAM memory region from a
* user-provided pointer. Accesses into the
* region will modify memory directly.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @ptr: memory to be mapped; must contain at least @size bytes.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
*/
void memory_region_init_ram_ptr(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
void *ptr);
/**
* memory_region_init_ram_device_ptr: Initialize RAM device memory region from
* a user-provided pointer.
*
* A RAM device represents a mapping to a physical device, such as to a PCI
* MMIO BAR of an vfio-pci assigned device. The memory region may be mapped
* into the VM address space and access to the region will modify memory
* directly. However, the memory region should not be included in a memory
* dump (device may not be enabled/mapped at the time of the dump), and
* operations incompatible with manipulating MMIO should be avoided. Replaces
* skip_dump flag.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: the name of the region.
* @size: size of the region.
* @ptr: memory to be mapped; must contain at least @size bytes.
*
* Note that this function does not do anything to cause the data in the
* RAM memory region to be migrated; that is the responsibility of the caller.
* (For RAM device memory regions, migrating the contents rarely makes sense.)
*/
void memory_region_init_ram_device_ptr(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
void *ptr);
/**
* memory_region_init_alias: Initialize a memory region that aliases all or a
* part of another memory region.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: used for debugging; not visible to the user or ABI
* @orig: the region to be referenced; @mr will be equivalent to
* @orig between @offset and @offset + @size - 1.
* @offset: start of the section in @orig to be referenced.
* @size: size of the region.
*/
void memory_region_init_alias(MemoryRegion *mr,
struct Object *owner,
const char *name,
MemoryRegion *orig,
hwaddr offset,
uint64_t size);
/**
* memory_region_init_rom_nomigrate: Initialize a ROM memory region.
*
* This has the same effect as calling memory_region_init_ram_nomigrate()
* and then marking the resulting region read-only with
* memory_region_set_readonly().
*
* Note that this function does not do anything to cause the data in the
* RAM side of the memory region to be migrated; that is the responsibility
* of the caller.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @errp: pointer to Error*, to store an error if it happens.
*/
void memory_region_init_rom_nomigrate(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_rom_device_nomigrate: Initialize a ROM memory region.
* Writes are handled via callbacks.
*
* Note that this function does not do anything to cause the data in the
* RAM side of the memory region to be migrated; that is the responsibility
* of the caller.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @ops: callbacks for write access handling (must not be NULL).
* @opaque: passed to the read and write callbacks of the @ops structure.
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @errp: pointer to Error*, to store an error if it happens.
*/
void memory_region_init_rom_device_nomigrate(MemoryRegion *mr,
struct Object *owner,
const MemoryRegionOps *ops,
void *opaque,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_reservation: Initialize a memory region that reserves
* I/O space.
*
* A reservation region primariy serves debugging purposes. It claims I/O
* space that is not supposed to be handled by QEMU itself. Any access via
* the memory API will cause an abort().
* This function is deprecated. Use memory_region_init_io() with NULL
* callbacks instead.
*
* @mr: the #MemoryRegion to be initialized
* @owner: the object that tracks the region's reference count
* @name: used for debugging; not visible to the user or ABI
* @size: size of the region.
*/
static inline void memory_region_init_reservation(MemoryRegion *mr,
Object *owner,
const char *name,
uint64_t size)
{
memory_region_init_io(mr, owner, NULL, mr, name, size);
}
/**
* memory_region_init_iommu: Initialize a memory region of a custom type
* that translates addresses
*
* An IOMMU region translates addresses and forwards accesses to a target
* memory region.
*
* @_iommu_mr: the #IOMMUMemoryRegion to be initialized
* @instance_size: the IOMMUMemoryRegion subclass instance size
* @mrtypename: the type name of the #IOMMUMemoryRegion
* @owner: the object that tracks the region's reference count
* @name: used for debugging; not visible to the user or ABI
* @size: size of the region.
*/
void memory_region_init_iommu(void *_iommu_mr,
size_t instance_size,
const char *mrtypename,
Object *owner,
const char *name,
uint64_t size);
/**
* memory_region_init_ram - Initialize RAM memory region. Accesses into the
* region will modify memory directly.
*
* @mr: the #MemoryRegion to be initialized
* @owner: the object that tracks the region's reference count (must be
* TYPE_DEVICE or a subclass of TYPE_DEVICE, or NULL)
* @name: name of the memory region
* @size: size of the region in bytes
* @errp: pointer to Error*, to store an error if it happens.
*
* This function allocates RAM for a board model or device, and
* arranges for it to be migrated (by calling vmstate_register_ram()
* if @owner is a DeviceState, or vmstate_register_ram_global() if
* @owner is NULL).
*
* TODO: Currently we restrict @owner to being either NULL (for
* global RAM regions with no owner) or devices, so that we can
* give the RAM block a unique name for migration purposes.
* We should lift this restriction and allow arbitrary Objects.
* If you pass a non-NULL non-device @owner then we will assert.
*/
void memory_region_init_ram(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_rom: Initialize a ROM memory region.
*
* This has the same effect as calling memory_region_init_ram()
* and then marking the resulting region read-only with
* memory_region_set_readonly(). This includes arranging for the
* contents to be migrated.
*
* TODO: Currently we restrict @owner to being either NULL (for
* global RAM regions with no owner) or devices, so that we can
* give the RAM block a unique name for migration purposes.
* We should lift this restriction and allow arbitrary Objects.
* If you pass a non-NULL non-device @owner then we will assert.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @errp: pointer to Error*, to store an error if it happens.
*/
void memory_region_init_rom(MemoryRegion *mr,
struct Object *owner,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_rom_device: Initialize a ROM memory region.
* Writes are handled via callbacks.
*
* This function initializes a memory region backed by RAM for reads
* and callbacks for writes, and arranges for the RAM backing to
* be migrated (by calling vmstate_register_ram()
* if @owner is a DeviceState, or vmstate_register_ram_global() if
* @owner is NULL).
*
* TODO: Currently we restrict @owner to being either NULL (for
* global RAM regions with no owner) or devices, so that we can
* give the RAM block a unique name for migration purposes.
* We should lift this restriction and allow arbitrary Objects.
* If you pass a non-NULL non-device @owner then we will assert.
*
* @mr: the #MemoryRegion to be initialized.
* @owner: the object that tracks the region's reference count
* @ops: callbacks for write access handling (must not be NULL).
* @name: Region name, becomes part of RAMBlock name used in migration stream
* must be unique within any device
* @size: size of the region.
* @errp: pointer to Error*, to store an error if it happens.
*/
void memory_region_init_rom_device(MemoryRegion *mr,
struct Object *owner,
const MemoryRegionOps *ops,
void *opaque,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_owner: get a memory region's owner.
*
* @mr: the memory region being queried.
*/
struct Object *memory_region_owner(MemoryRegion *mr);
/**
* memory_region_size: get a memory region's size.
*
* @mr: the memory region being queried.
*/
uint64_t memory_region_size(MemoryRegion *mr);
/**
* memory_region_is_ram: check whether a memory region is random access
*
* Returns %true is a memory region is random access.
*
* @mr: the memory region being queried
*/
static inline bool memory_region_is_ram(MemoryRegion *mr)
{
return mr->ram;
}
/**
* memory_region_is_ram_device: check whether a memory region is a ram device
*
* Returns %true is a memory region is a device backed ram region
*
* @mr: the memory region being queried
*/
bool memory_region_is_ram_device(MemoryRegion *mr);
/**
* memory_region_is_romd: check whether a memory region is in ROMD mode
*
* Returns %true if a memory region is a ROM device and currently set to allow
* direct reads.
*
* @mr: the memory region being queried
*/
static inline bool memory_region_is_romd(MemoryRegion *mr)
{
return mr->rom_device && mr->romd_mode;
}
/**
* memory_region_get_iommu: check whether a memory region is an iommu
*
* Returns pointer to IOMMUMemoryRegion if a memory region is an iommu,
* otherwise NULL.
*
* @mr: the memory region being queried
*/
static inline IOMMUMemoryRegion *memory_region_get_iommu(MemoryRegion *mr)
{
if (mr->alias) {
return memory_region_get_iommu(mr->alias);
}
if (mr->is_iommu) {
return (IOMMUMemoryRegion *) mr;
}
return NULL;
}
/**
* memory_region_get_iommu_class_nocheck: returns iommu memory region class
* if an iommu or NULL if not
*
* Returns pointer to IOMMUMemoryRegionClass if a memory region is an iommu,
* otherwise NULL. This is fast path avoiding QOM checking, use with caution.
*
* @mr: the memory region being queried
*/
static inline IOMMUMemoryRegionClass *memory_region_get_iommu_class_nocheck(
IOMMUMemoryRegion *iommu_mr)
{
return (IOMMUMemoryRegionClass *) (((Object *)iommu_mr)->class);
}
#define memory_region_is_iommu(mr) (memory_region_get_iommu(mr) != NULL)
/**
* memory_region_iommu_get_min_page_size: get minimum supported page size
* for an iommu
*
* Returns minimum supported page size for an iommu.
*
* @iommu_mr: the memory region being queried
*/
uint64_t memory_region_iommu_get_min_page_size(IOMMUMemoryRegion *iommu_mr);
/**
* memory_region_notify_iommu: notify a change in an IOMMU translation entry.
*
* The notification type will be decided by entry.perm bits:
*
* - For UNMAP (cache invalidation) notifies: set entry.perm to IOMMU_NONE.
* - For MAP (newly added entry) notifies: set entry.perm to the
* permission of the page (which is definitely !IOMMU_NONE).
*
* Note: for any IOMMU implementation, an in-place mapping change
* should be notified with an UNMAP followed by a MAP.
*
* @iommu_mr: the memory region that was changed
* @entry: the new entry in the IOMMU translation table. The entry
* replaces all old entries for the same virtual I/O address range.
* Deleted entries have .@perm == 0.
*/
void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
IOMMUTLBEntry entry);
/**
* memory_region_notify_one: notify a change in an IOMMU translation
* entry to a single notifier
*
* This works just like memory_region_notify_iommu(), but it only
* notifies a specific notifier, not all of them.
*
* @notifier: the notifier to be notified
* @entry: the new entry in the IOMMU translation table. The entry
* replaces all old entries for the same virtual I/O address range.
* Deleted entries have .@perm == 0.
*/
void memory_region_notify_one(IOMMUNotifier *notifier,
IOMMUTLBEntry *entry);
/**
* memory_region_register_iommu_notifier: register a notifier for changes to
* IOMMU translation entries.
*
* @mr: the memory region to observe
* @n: the IOMMUNotifier to be added; the notify callback receives a
* pointer to an #IOMMUTLBEntry as the opaque value; the pointer
* ceases to be valid on exit from the notifier.
*/
void memory_region_register_iommu_notifier(MemoryRegion *mr,
IOMMUNotifier *n);
memory: Allow replay of IOMMU mapping notifications When we have guest visible IOMMUs, we allow notifiers to be registered which will be informed of all changes to IOMMU mappings. This is used by vfio to keep the host IOMMU mappings in sync with guest IOMMU mappings. However, unlike with a memory region listener, an iommu notifier won't be told about any mappings which already exist in the (guest) IOMMU at the time it is registered. This can cause problems if hotplugging a VFIO device onto a guest bus which had existing guest IOMMU mappings, but didn't previously have an VFIO devices (and hence no host IOMMU mappings). This adds a memory_region_iommu_replay() function to handle this case. It replays any existing mappings in an IOMMU memory region to a specified notifier. Because the IOMMU memory region doesn't internally remember the granularity of the guest IOMMU it has a small hack where the caller must specify a granularity at which to replay mappings. If there are finer mappings in the guest IOMMU these will be reported in the iotlb structures passed to the notifier which it must handle (probably causing it to flag an error). This isn't new - the VFIO iommu notifier must already handle notifications about guest IOMMU mappings too short for it to represent in the host IOMMU. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-30 05:13:55 +03:00
/**
* memory_region_iommu_replay: replay existing IOMMU translations to
* a notifier with the minimum page granularity returned by
* mr->iommu_ops->get_page_size().
memory: Allow replay of IOMMU mapping notifications When we have guest visible IOMMUs, we allow notifiers to be registered which will be informed of all changes to IOMMU mappings. This is used by vfio to keep the host IOMMU mappings in sync with guest IOMMU mappings. However, unlike with a memory region listener, an iommu notifier won't be told about any mappings which already exist in the (guest) IOMMU at the time it is registered. This can cause problems if hotplugging a VFIO device onto a guest bus which had existing guest IOMMU mappings, but didn't previously have an VFIO devices (and hence no host IOMMU mappings). This adds a memory_region_iommu_replay() function to handle this case. It replays any existing mappings in an IOMMU memory region to a specified notifier. Because the IOMMU memory region doesn't internally remember the granularity of the guest IOMMU it has a small hack where the caller must specify a granularity at which to replay mappings. If there are finer mappings in the guest IOMMU these will be reported in the iotlb structures passed to the notifier which it must handle (probably causing it to flag an error). This isn't new - the VFIO iommu notifier must already handle notifications about guest IOMMU mappings too short for it to represent in the host IOMMU. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-30 05:13:55 +03:00
*
* @iommu_mr: the memory region to observe
memory: Allow replay of IOMMU mapping notifications When we have guest visible IOMMUs, we allow notifiers to be registered which will be informed of all changes to IOMMU mappings. This is used by vfio to keep the host IOMMU mappings in sync with guest IOMMU mappings. However, unlike with a memory region listener, an iommu notifier won't be told about any mappings which already exist in the (guest) IOMMU at the time it is registered. This can cause problems if hotplugging a VFIO device onto a guest bus which had existing guest IOMMU mappings, but didn't previously have an VFIO devices (and hence no host IOMMU mappings). This adds a memory_region_iommu_replay() function to handle this case. It replays any existing mappings in an IOMMU memory region to a specified notifier. Because the IOMMU memory region doesn't internally remember the granularity of the guest IOMMU it has a small hack where the caller must specify a granularity at which to replay mappings. If there are finer mappings in the guest IOMMU these will be reported in the iotlb structures passed to the notifier which it must handle (probably causing it to flag an error). This isn't new - the VFIO iommu notifier must already handle notifications about guest IOMMU mappings too short for it to represent in the host IOMMU. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-30 05:13:55 +03:00
* @n: the notifier to which to replay iommu mappings
*/
void memory_region_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n);
memory: Allow replay of IOMMU mapping notifications When we have guest visible IOMMUs, we allow notifiers to be registered which will be informed of all changes to IOMMU mappings. This is used by vfio to keep the host IOMMU mappings in sync with guest IOMMU mappings. However, unlike with a memory region listener, an iommu notifier won't be told about any mappings which already exist in the (guest) IOMMU at the time it is registered. This can cause problems if hotplugging a VFIO device onto a guest bus which had existing guest IOMMU mappings, but didn't previously have an VFIO devices (and hence no host IOMMU mappings). This adds a memory_region_iommu_replay() function to handle this case. It replays any existing mappings in an IOMMU memory region to a specified notifier. Because the IOMMU memory region doesn't internally remember the granularity of the guest IOMMU it has a small hack where the caller must specify a granularity at which to replay mappings. If there are finer mappings in the guest IOMMU these will be reported in the iotlb structures passed to the notifier which it must handle (probably causing it to flag an error). This isn't new - the VFIO iommu notifier must already handle notifications about guest IOMMU mappings too short for it to represent in the host IOMMU. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-30 05:13:55 +03:00
/**
* memory_region_iommu_replay_all: replay existing IOMMU translations
* to all the notifiers registered.
*
* @iommu_mr: the memory region to observe
*/
void memory_region_iommu_replay_all(IOMMUMemoryRegion *iommu_mr);
/**
* memory_region_unregister_iommu_notifier: unregister a notifier for
* changes to IOMMU translation entries.
*
* @mr: the memory region which was observed and for which notity_stopped()
* needs to be called
* @n: the notifier to be removed.
*/
void memory_region_unregister_iommu_notifier(MemoryRegion *mr,
IOMMUNotifier *n);
/**
* memory_region_iommu_get_attr: return an IOMMU attr if get_attr() is
* defined on the IOMMU.
*
* Returns 0 if succeded, error code otherwise.
*
* @iommu_mr: the memory region
* @attr: the requested attribute
* @data: a pointer to the requested attribute data
*/
int memory_region_iommu_get_attr(IOMMUMemoryRegion *iommu_mr,
enum IOMMUMemoryRegionAttr attr,
void *data);
/**
* memory_region_name: get a memory region's name
*
* Returns the string that was used to initialize the memory region.
*
* @mr: the memory region being queried
*/
const char *memory_region_name(const MemoryRegion *mr);
/**
* memory_region_is_logging: return whether a memory region is logging writes
*
* Returns %true if the memory region is logging writes for the given client
*
* @mr: the memory region being queried
* @client: the client being queried
*/
bool memory_region_is_logging(MemoryRegion *mr, uint8_t client);
/**
* memory_region_get_dirty_log_mask: return the clients for which a
* memory region is logging writes.
*
* Returns a bitmap of clients, in which the DIRTY_MEMORY_* constants
* are the bit indices.
*
* @mr: the memory region being queried
*/
uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr);
/**
* memory_region_is_rom: check whether a memory region is ROM
*
* Returns %true is a memory region is read-only memory.
*
* @mr: the memory region being queried
*/
static inline bool memory_region_is_rom(MemoryRegion *mr)
{
return mr->ram && mr->readonly;
}
/**
* memory_region_get_fd: Get a file descriptor backing a RAM memory region.
*
* Returns a file descriptor backing a file-based RAM memory region,
* or -1 if the region is not a file-based RAM memory region.
*
* @mr: the RAM or alias memory region being queried.
*/
int memory_region_get_fd(MemoryRegion *mr);
/**
* memory_region_from_host: Convert a pointer into a RAM memory region
* and an offset within it.
*
* Given a host pointer inside a RAM memory region (created with
* memory_region_init_ram() or memory_region_init_ram_ptr()), return
* the MemoryRegion and the offset within it.
*
* Use with care; by the time this function returns, the returned pointer is
* not protected by RCU anymore. If the caller is not within an RCU critical
* section and does not hold the iothread lock, it must have other means of
* protecting the pointer, such as a reference to the region that includes
* the incoming ram_addr_t.
*
* @ptr: the host pointer to be converted
* @offset: the offset within memory region
*/
MemoryRegion *memory_region_from_host(void *ptr, ram_addr_t *offset);
/**
* memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
*
* Returns a host pointer to a RAM memory region (created with
* memory_region_init_ram() or memory_region_init_ram_ptr()).
*
* Use with care; by the time this function returns, the returned pointer is
* not protected by RCU anymore. If the caller is not within an RCU critical
* section and does not hold the iothread lock, it must have other means of
* protecting the pointer, such as a reference to the region that includes
* the incoming ram_addr_t.
*
* @mr: the memory region being queried.
*/
void *memory_region_get_ram_ptr(MemoryRegion *mr);
/* memory_region_ram_resize: Resize a RAM region.
*
* Only legal before guest might have detected the memory size: e.g. on
* incoming migration, or right after reset.
*
* @mr: a memory region created with @memory_region_init_resizeable_ram.
* @newsize: the new size the region
* @errp: pointer to Error*, to store an error if it happens.
*/
void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize,
Error **errp);
/**
* memory_region_set_log: Turn dirty logging on or off for a region.
*
* Turns dirty logging on or off for a specified client (display, migration).
* Only meaningful for RAM regions.
*
* @mr: the memory region being updated.
* @log: whether dirty logging is to be enabled or disabled.
* @client: the user of the logging information; %DIRTY_MEMORY_VGA only.
*/
void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);
/**
* memory_region_get_dirty: Check whether a range of bytes is dirty
* for a specified client.
*
* Checks whether a range of bytes has been written to since the last
* call to memory_region_reset_dirty() with the same @client. Dirty logging
* must be enabled.
*
* @mr: the memory region being queried.
* @addr: the address (relative to the start of the region) being queried.
* @size: the size of the range being queried.
* @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
* %DIRTY_MEMORY_VGA.
*/
bool memory_region_get_dirty(MemoryRegion *mr, hwaddr addr,
hwaddr size, unsigned client);
/**
* memory_region_set_dirty: Mark a range of bytes as dirty in a memory region.
*
* Marks a range of bytes as dirty, after it has been dirtied outside
* guest code.
*
* @mr: the memory region being dirtied.
* @addr: the address (relative to the start of the region) being dirtied.
* @size: size of the range being dirtied.
*/
void memory_region_set_dirty(MemoryRegion *mr, hwaddr addr,
hwaddr size);
/**
* memory_region_snapshot_and_clear_dirty: Get a snapshot of the dirty
* bitmap and clear it.
*
* Creates a snapshot of the dirty bitmap, clears the dirty bitmap and
* returns the snapshot. The snapshot can then be used to query dirty
* status, using memory_region_snapshot_get_dirty. Snapshotting allows
* querying the same page multiple times, which is especially useful for
* display updates where the scanlines often are not page aligned.
*
* The dirty bitmap region which gets copyed into the snapshot (and
* cleared afterwards) can be larger than requested. The boundaries
* are rounded up/down so complete bitmap longs (covering 64 pages on
* 64bit hosts) can be copied over into the bitmap snapshot. Which
* isn't a problem for display updates as the extra pages are outside
* the visible area, and in case the visible area changes a full
* display redraw is due anyway. Should other use cases for this
* function emerge we might have to revisit this implementation
* detail.
*
* Use g_free to release DirtyBitmapSnapshot.
*
* @mr: the memory region being queried.
* @addr: the address (relative to the start of the region) being queried.
* @size: the size of the range being queried.
* @client: the user of the logging information; typically %DIRTY_MEMORY_VGA.
*/
DirtyBitmapSnapshot *memory_region_snapshot_and_clear_dirty(MemoryRegion *mr,
hwaddr addr,
hwaddr size,
unsigned client);
/**
* memory_region_snapshot_get_dirty: Check whether a range of bytes is dirty
* in the specified dirty bitmap snapshot.
*
* @mr: the memory region being queried.
* @snap: the dirty bitmap snapshot
* @addr: the address (relative to the start of the region) being queried.
* @size: the size of the range being queried.
*/
bool memory_region_snapshot_get_dirty(MemoryRegion *mr,
DirtyBitmapSnapshot *snap,
hwaddr addr, hwaddr size);
/**
* memory_region_reset_dirty: Mark a range of pages as clean, for a specified
* client.
*
* Marks a range of pages as no longer dirty.
*
* @mr: the region being updated.
* @addr: the start of the subrange being cleaned.
* @size: the size of the subrange being cleaned.
* @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
* %DIRTY_MEMORY_VGA.
*/
void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
hwaddr size, unsigned client);
/**
* memory_region_set_readonly: Turn a memory region read-only (or read-write)
*
* Allows a memory region to be marked as read-only (turning it into a ROM).
* only useful on RAM regions.
*
* @mr: the region being updated.
* @readonly: whether rhe region is to be ROM or RAM.
*/
void memory_region_set_readonly(MemoryRegion *mr, bool readonly);
/**
* memory_region_rom_device_set_romd: enable/disable ROMD mode
*
* Allows a ROM device (initialized with memory_region_init_rom_device() to
* set to ROMD mode (default) or MMIO mode. When it is in ROMD mode, the
* device is mapped to guest memory and satisfies read access directly.
* When in MMIO mode, reads are forwarded to the #MemoryRegion.read function.
* Writes are always handled by the #MemoryRegion.write function.
*
* @mr: the memory region to be updated
* @romd_mode: %true to put the region into ROMD mode
*/
void memory_region_rom_device_set_romd(MemoryRegion *mr, bool romd_mode);
/**
* memory_region_set_coalescing: Enable memory coalescing for the region.
*
* Enabled writes to a region to be queued for later processing. MMIO ->write
* callbacks may be delayed until a non-coalesced MMIO is issued.
* Only useful for IO regions. Roughly similar to write-combining hardware.
*
* @mr: the memory region to be write coalesced
*/
void memory_region_set_coalescing(MemoryRegion *mr);
/**
* memory_region_add_coalescing: Enable memory coalescing for a sub-range of
* a region.
*
* Like memory_region_set_coalescing(), but works on a sub-range of a region.
* Multiple calls can be issued coalesced disjoint ranges.
*
* @mr: the memory region to be updated.
* @offset: the start of the range within the region to be coalesced.
* @size: the size of the subrange to be coalesced.
*/
void memory_region_add_coalescing(MemoryRegion *mr,
hwaddr offset,
uint64_t size);
/**
* memory_region_clear_coalescing: Disable MMIO coalescing for the region.
*
* Disables any coalescing caused by memory_region_set_coalescing() or
* memory_region_add_coalescing(). Roughly equivalent to uncacheble memory
* hardware.
*
* @mr: the memory region to be updated.
*/
void memory_region_clear_coalescing(MemoryRegion *mr);
/**
* memory_region_set_flush_coalesced: Enforce memory coalescing flush before
* accesses.
*
* Ensure that pending coalesced MMIO request are flushed before the memory
* region is accessed. This property is automatically enabled for all regions
* passed to memory_region_set_coalescing() and memory_region_add_coalescing().
*
* @mr: the memory region to be updated.
*/
void memory_region_set_flush_coalesced(MemoryRegion *mr);
/**
* memory_region_clear_flush_coalesced: Disable memory coalescing flush before
* accesses.
*
* Clear the automatic coalesced MMIO flushing enabled via
* memory_region_set_flush_coalesced. Note that this service has no effect on
* memory regions that have MMIO coalescing enabled for themselves. For them,
* automatic flushing will stop once coalescing is disabled.
*
* @mr: the memory region to be updated.
*/
void memory_region_clear_flush_coalesced(MemoryRegion *mr);
/**
* memory_region_clear_global_locking: Declares that access processing does
* not depend on the QEMU global lock.
*
* By clearing this property, accesses to the memory region will be processed
* outside of QEMU's global lock (unless the lock is held on when issuing the
* access request). In this case, the device model implementing the access
* handlers is responsible for synchronization of concurrency.
*
* @mr: the memory region to be updated.
*/
void memory_region_clear_global_locking(MemoryRegion *mr);
/**
* memory_region_add_eventfd: Request an eventfd to be triggered when a word
* is written to a location.
*
* Marks a word in an IO region (initialized with memory_region_init_io())
* as a trigger for an eventfd event. The I/O callback will not be called.
* The caller must be prepared to handle failure (that is, take the required
* action if the callback _is_ called).
*
* @mr: the memory region being updated.
* @addr: the address within @mr that is to be monitored
* @size: the size of the access to trigger the eventfd
* @match_data: whether to match against @data, instead of just @addr
* @data: the data to match against the guest write
* @e: event notifier to be triggered when @addr, @size, and @data all match.
**/
void memory_region_add_eventfd(MemoryRegion *mr,
hwaddr addr,
unsigned size,
bool match_data,
uint64_t data,
EventNotifier *e);
/**
* memory_region_del_eventfd: Cancel an eventfd.
*
* Cancels an eventfd trigger requested by a previous
* memory_region_add_eventfd() call.
*
* @mr: the memory region being updated.
* @addr: the address within @mr that is to be monitored
* @size: the size of the access to trigger the eventfd
* @match_data: whether to match against @data, instead of just @addr
* @data: the data to match against the guest write
* @e: event notifier to be triggered when @addr, @size, and @data all match.
*/
void memory_region_del_eventfd(MemoryRegion *mr,
hwaddr addr,
unsigned size,
bool match_data,
uint64_t data,
EventNotifier *e);
/**
* memory_region_add_subregion: Add a subregion to a container.
*
* Adds a subregion at @offset. The subregion may not overlap with other
* subregions (except for those explicitly marked as overlapping). A region
* may only be added once as a subregion (unless removed with
* memory_region_del_subregion()); use memory_region_init_alias() if you
* want a region to be a subregion in multiple locations.
*
* @mr: the region to contain the new subregion; must be a container
* initialized with memory_region_init().
* @offset: the offset relative to @mr where @subregion is added.
* @subregion: the subregion to be added.
*/
void memory_region_add_subregion(MemoryRegion *mr,
hwaddr offset,
MemoryRegion *subregion);
/**
* memory_region_add_subregion_overlap: Add a subregion to a container
* with overlap.
*
* Adds a subregion at @offset. The subregion may overlap with other
* subregions. Conflicts are resolved by having a higher @priority hide a
* lower @priority. Subregions without priority are taken as @priority 0.
* A region may only be added once as a subregion (unless removed with
* memory_region_del_subregion()); use memory_region_init_alias() if you
* want a region to be a subregion in multiple locations.
*
* @mr: the region to contain the new subregion; must be a container
* initialized with memory_region_init().
* @offset: the offset relative to @mr where @subregion is added.
* @subregion: the subregion to be added.
* @priority: used for resolving overlaps; highest priority wins.
*/
void memory_region_add_subregion_overlap(MemoryRegion *mr,
hwaddr offset,
MemoryRegion *subregion,
int priority);
/**
* memory_region_get_ram_addr: Get the ram address associated with a memory
* region
*/
ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr);
uint64_t memory_region_get_alignment(const MemoryRegion *mr);
/**
* memory_region_del_subregion: Remove a subregion.
*
* Removes a subregion from its container.
*
* @mr: the container to be updated.
* @subregion: the region being removed; must be a current subregion of @mr.
*/
void memory_region_del_subregion(MemoryRegion *mr,
MemoryRegion *subregion);
/*
* memory_region_set_enabled: dynamically enable or disable a region
*
* Enables or disables a memory region. A disabled memory region
* ignores all accesses to itself and its subregions. It does not
* obscure sibling subregions with lower priority - it simply behaves as
* if it was removed from the hierarchy.
*
* Regions default to being enabled.
*
* @mr: the region to be updated
* @enabled: whether to enable or disable the region
*/
void memory_region_set_enabled(MemoryRegion *mr, bool enabled);
/*
* memory_region_set_address: dynamically update the address of a region
*
* Dynamically updates the address of a region, relative to its container.
* May be used on regions are currently part of a memory hierarchy.
*
* @mr: the region to be updated
* @addr: new address, relative to container region
*/
void memory_region_set_address(MemoryRegion *mr, hwaddr addr);
/*
* memory_region_set_size: dynamically update the size of a region.
*
* Dynamically updates the size of a region.
*
* @mr: the region to be updated
* @size: used size of the region.
*/
void memory_region_set_size(MemoryRegion *mr, uint64_t size);
/*
* memory_region_set_alias_offset: dynamically update a memory alias's offset
*
* Dynamically updates the offset into the target region that an alias points
* to, as if the fourth argument to memory_region_init_alias() has changed.
*
* @mr: the #MemoryRegion to be updated; should be an alias.
* @offset: the new offset into the target memory region
*/
void memory_region_set_alias_offset(MemoryRegion *mr,
hwaddr offset);
/**
* memory_region_present: checks if an address relative to a @container
* translates into #MemoryRegion within @container
*
* Answer whether a #MemoryRegion within @container covers the address
* @addr.
*
* @container: a #MemoryRegion within which @addr is a relative address
* @addr: the area within @container to be searched
*/
bool memory_region_present(MemoryRegion *container, hwaddr addr);
/**
* memory_region_is_mapped: returns true if #MemoryRegion is mapped
* into any address space.
*
* @mr: a #MemoryRegion which should be checked if it's mapped
*/
bool memory_region_is_mapped(MemoryRegion *mr);
/**
* memory_region_find: translate an address/size relative to a
* MemoryRegion into a #MemoryRegionSection.
*
* Locates the first #MemoryRegion within @mr that overlaps the range
* given by @addr and @size.
*
* Returns a #MemoryRegionSection that describes a contiguous overlap.
* It will have the following characteristics:
* .@size = 0 iff no overlap was found
* .@mr is non-%NULL iff an overlap was found
*
* Remember that in the return value the @offset_within_region is
* relative to the returned region (in the .@mr field), not to the
* @mr argument.
*
* Similarly, the .@offset_within_address_space is relative to the
* address space that contains both regions, the passed and the
* returned one. However, in the special case where the @mr argument
* has no container (and thus is the root of the address space), the
* following will hold:
* .@offset_within_address_space >= @addr
* .@offset_within_address_space + .@size <= @addr + @size
*
* @mr: a MemoryRegion within which @addr is a relative address
* @addr: start of the area within @as to be searched
* @size: size of the area to be searched
*/
MemoryRegionSection memory_region_find(MemoryRegion *mr,
hwaddr addr, uint64_t size);
/**
* memory_global_dirty_log_sync: synchronize the dirty log for all memory
*
* Synchronizes the dirty page log for all address spaces.
*/
void memory_global_dirty_log_sync(void);
/**
* memory_region_transaction_begin: Start a transaction.
*
* During a transaction, changes will be accumulated and made visible
* only when the transaction ends (is committed).
*/
void memory_region_transaction_begin(void);
/**
* memory_region_transaction_commit: Commit a transaction and make changes
* visible to the guest.
*/
void memory_region_transaction_commit(void);
/**
* memory_listener_register: register callbacks to be called when memory
* sections are mapped or unmapped into an address
* space
*
* @listener: an object containing the callbacks to be called
* @filter: if non-%NULL, only regions in this address space will be observed
*/
void memory_listener_register(MemoryListener *listener, AddressSpace *filter);
/**
* memory_listener_unregister: undo the effect of memory_listener_register()
*
* @listener: an object containing the callbacks to be removed
*/
void memory_listener_unregister(MemoryListener *listener);
/**
* memory_global_dirty_log_start: begin dirty logging for all regions
*/
void memory_global_dirty_log_start(void);
/**
* memory_global_dirty_log_stop: end dirty logging for all regions
*/
void memory_global_dirty_log_stop(void);
void mtree_info(fprintf_function mon_printf, void *f, bool flatview,
bool dispatch_tree);
/**
* memory_region_request_mmio_ptr: request a pointer to an mmio
* MemoryRegion. If it is possible map a RAM MemoryRegion with this pointer.
* When the device wants to invalidate the pointer it will call
* memory_region_invalidate_mmio_ptr.
*
* @mr: #MemoryRegion to check
* @addr: address within that region
*
* Returns true on success, false otherwise.
*/
bool memory_region_request_mmio_ptr(MemoryRegion *mr, hwaddr addr);
/**
* memory_region_invalidate_mmio_ptr: invalidate the pointer to an mmio
* previously requested.
* In the end that means that if something wants to execute from this area it
* will need to request the pointer again.
*
* @mr: #MemoryRegion associated to the pointer.
* @offset: offset within the memory region
* @size: size of that area.
*/
void memory_region_invalidate_mmio_ptr(MemoryRegion *mr, hwaddr offset,
unsigned size);
/**
* memory_region_dispatch_read: perform a read directly to the specified
* MemoryRegion.
*
* @mr: #MemoryRegion to access
* @addr: address within that region
* @pval: pointer to uint64_t which the data is written to
* @size: size of the access in bytes
* @attrs: memory transaction attributes to use for the access
*/
MemTxResult memory_region_dispatch_read(MemoryRegion *mr,
hwaddr addr,
uint64_t *pval,
unsigned size,
MemTxAttrs attrs);
/**
* memory_region_dispatch_write: perform a write directly to the specified
* MemoryRegion.
*
* @mr: #MemoryRegion to access
* @addr: address within that region
* @data: data to write
* @size: size of the access in bytes
* @attrs: memory transaction attributes to use for the access
*/
MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
hwaddr addr,
uint64_t data,
unsigned size,
MemTxAttrs attrs);
/**
* address_space_init: initializes an address space
*
* @as: an uninitialized #AddressSpace
* @root: a #MemoryRegion that routes addresses for the address space
* @name: an address space name. The name is only used for debugging
* output.
*/
void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name);
/**
* address_space_destroy: destroy an address space
*
* Releases all resources associated with an address space. After an address space
* is destroyed, its root memory region (given by address_space_init()) may be destroyed
* as well.
*
* @as: address space to be destroyed
*/
void address_space_destroy(AddressSpace *as);
/**
* address_space_rw: read from or write to an address space.
*
* Return a MemTxResult indicating whether the operation succeeded
* or failed (eg unassigned memory, device rejected the transaction,
* IOMMU fault).
*
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @attrs: memory transaction attributes
* @buf: buffer with the data transferred
* @len: the number of bytes to read or write
* @is_write: indicates the transfer direction
*/
MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf,
int len, bool is_write);
/**
* address_space_write: write to address space.
*
* Return a MemTxResult indicating whether the operation succeeded
* or failed (eg unassigned memory, device rejected the transaction,
* IOMMU fault).
*
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @attrs: memory transaction attributes
* @buf: buffer with the data transferred
* @len: the number of bytes to write
*/
MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs,
const uint8_t *buf, int len);
/* address_space_ld*: load from an address space
* address_space_st*: store to an address space
*
* These functions perform a load or store of the byte, word,
* longword or quad to the specified address within the AddressSpace.
* The _le suffixed functions treat the data as little endian;
* _be indicates big endian; no suffix indicates "same endianness
* as guest CPU".
*
* The "guest CPU endianness" accessors are deprecated for use outside
* target-* code; devices should be CPU-agnostic and use either the LE
* or the BE accessors.
*
* @as #AddressSpace to be accessed
* @addr: address within that address space
* @val: data value, for stores
* @attrs: memory transaction attributes
* @result: location to write the success/failure of the transaction;
* if NULL, this information is discarded
*/
uint32_t address_space_ldub(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_lduw_le(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_lduw_be(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_ldl_le(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_ldl_be(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint64_t address_space_ldq_le(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint64_t address_space_ldq_be(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stb(AddressSpace *as, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stw_le(AddressSpace *as, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stw_be(AddressSpace *as, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stl_le(AddressSpace *as, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stl_be(AddressSpace *as, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stq_le(AddressSpace *as, hwaddr addr, uint64_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stq_be(AddressSpace *as, hwaddr addr, uint64_t val,
MemTxAttrs attrs, MemTxResult *result);
uint32_t ldub_phys(AddressSpace *as, hwaddr addr);
uint32_t lduw_le_phys(AddressSpace *as, hwaddr addr);
uint32_t lduw_be_phys(AddressSpace *as, hwaddr addr);
uint32_t ldl_le_phys(AddressSpace *as, hwaddr addr);
uint32_t ldl_be_phys(AddressSpace *as, hwaddr addr);
uint64_t ldq_le_phys(AddressSpace *as, hwaddr addr);
uint64_t ldq_be_phys(AddressSpace *as, hwaddr addr);
void stb_phys(AddressSpace *as, hwaddr addr, uint32_t val);
void stw_le_phys(AddressSpace *as, hwaddr addr, uint32_t val);
void stw_be_phys(AddressSpace *as, hwaddr addr, uint32_t val);
void stl_le_phys(AddressSpace *as, hwaddr addr, uint32_t val);
void stl_be_phys(AddressSpace *as, hwaddr addr, uint32_t val);
void stq_le_phys(AddressSpace *as, hwaddr addr, uint64_t val);
void stq_be_phys(AddressSpace *as, hwaddr addr, uint64_t val);
struct MemoryRegionCache {
hwaddr xlat;
hwaddr len;
AddressSpace *as;
};
#define MEMORY_REGION_CACHE_INVALID ((MemoryRegionCache) { .as = NULL })
/* address_space_cache_init: prepare for repeated access to a physical
* memory region
*
* @cache: #MemoryRegionCache to be filled
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @len: length of buffer
* @is_write: indicates the transfer direction
*
* Will only work with RAM, and may map a subset of the requested range by
* returning a value that is less than @len. On failure, return a negative
* errno value.
*
* Because it only works with RAM, this function can be used for
* read-modify-write operations. In this case, is_write should be %true.
*
* Note that addresses passed to the address_space_*_cached functions
* are relative to @addr.
*/
int64_t address_space_cache_init(MemoryRegionCache *cache,
AddressSpace *as,
hwaddr addr,
hwaddr len,
bool is_write);
/**
* address_space_cache_invalidate: complete a write to a #MemoryRegionCache
*
* @cache: The #MemoryRegionCache to operate on.
* @addr: The first physical address that was written, relative to the
* address that was passed to @address_space_cache_init.
* @access_len: The number of bytes that were written starting at @addr.
*/
void address_space_cache_invalidate(MemoryRegionCache *cache,
hwaddr addr,
hwaddr access_len);
/**
* address_space_cache_destroy: free a #MemoryRegionCache
*
* @cache: The #MemoryRegionCache whose memory should be released.
*/
void address_space_cache_destroy(MemoryRegionCache *cache);
/* address_space_ld*_cached: load from a cached #MemoryRegion
* address_space_st*_cached: store into a cached #MemoryRegion
*
* These functions perform a load or store of the byte, word,
* longword or quad to the specified address. The address is
* a physical address in the AddressSpace, but it must lie within
* a #MemoryRegion that was mapped with address_space_cache_init.
*
* The _le suffixed functions treat the data as little endian;
* _be indicates big endian; no suffix indicates "same endianness
* as guest CPU".
*
* The "guest CPU endianness" accessors are deprecated for use outside
* target-* code; devices should be CPU-agnostic and use either the LE
* or the BE accessors.
*
* @cache: previously initialized #MemoryRegionCache to be accessed
* @addr: address within the address space
* @val: data value, for stores
* @attrs: memory transaction attributes
* @result: location to write the success/failure of the transaction;
* if NULL, this information is discarded
*/
uint32_t address_space_ldub_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_lduw_le_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_lduw_be_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_ldl_le_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint32_t address_space_ldl_be_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint64_t address_space_ldq_le_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
uint64_t address_space_ldq_be_cached(MemoryRegionCache *cache, hwaddr addr,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stb_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stw_le_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stw_be_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stl_le_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stl_be_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stq_le_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val,
MemTxAttrs attrs, MemTxResult *result);
void address_space_stq_be_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val,
MemTxAttrs attrs, MemTxResult *result);
uint32_t ldub_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint32_t lduw_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint32_t lduw_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint32_t ldl_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint32_t ldl_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint64_t ldq_le_phys_cached(MemoryRegionCache *cache, hwaddr addr);
uint64_t ldq_be_phys_cached(MemoryRegionCache *cache, hwaddr addr);
void stb_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
void stw_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
void stw_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
void stl_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
void stl_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint32_t val);
void stq_le_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val);
void stq_be_phys_cached(MemoryRegionCache *cache, hwaddr addr, uint64_t val);
/* address_space_get_iotlb_entry: translate an address into an IOTLB
* entry. Should be called from an RCU critical section.
*/
IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
bool is_write);
/* address_space_translate: translate an address range into an address space
* into a MemoryRegion and an address range into that section. Should be
* called from an RCU critical section, to avoid that the last reference
* to the returned region disappears after address_space_translate returns.
*
* @fv: #FlatView to be accessed
* @addr: address within that address space
* @xlat: pointer to address within the returned memory region section's
* #MemoryRegion.
* @len: pointer to length
* @is_write: indicates the transfer direction
*/
MemoryRegion *flatview_translate(FlatView *fv,
hwaddr addr, hwaddr *xlat,
hwaddr *len, bool is_write);
static inline MemoryRegion *address_space_translate(AddressSpace *as,
hwaddr addr, hwaddr *xlat,
hwaddr *len, bool is_write)
{
return flatview_translate(address_space_to_flatview(as),
addr, xlat, len, is_write);
}
/* address_space_access_valid: check for validity of accessing an address
* space range
*
* Check whether memory is assigned to the given address space range, and
* access is permitted by any IOMMU regions that are active for the address
* space.
*
* For now, addr and len should be aligned to a page size. This limitation
* will be lifted in the future.
*
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @len: length of the area to be checked
* @is_write: indicates the transfer direction
*/
bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_write);
/* address_space_map: map a physical memory region into a host virtual address
*
* May map a subset of the requested range, given by and returned in @plen.
* May return %NULL if resources needed to perform the mapping are exhausted.
* Use only for reads OR writes - not for read-modify-write operations.
* Use cpu_register_map_client() to know when retrying the map operation is
* likely to succeed.
*
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @plen: pointer to length of buffer; updated on return
* @is_write: indicates the transfer direction
*/
void *address_space_map(AddressSpace *as, hwaddr addr,
hwaddr *plen, bool is_write);
/* address_space_unmap: Unmaps a memory region previously mapped by address_space_map()
*
* Will also mark the memory as dirty if @is_write == %true. @access_len gives
* the amount of memory that was actually read or written by the caller.
*
* @as: #AddressSpace used
* @buffer: host pointer as returned by address_space_map()
* @len: buffer length as returned by address_space_map()
* @access_len: amount of data actually transferred
* @is_write: indicates the transfer direction
*/
void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
int is_write, hwaddr access_len);
/* Internal functions, part of the implementation of address_space_read. */
MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf, int len);
MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf,
int len, hwaddr addr1, hwaddr l,
MemoryRegion *mr);
void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr);
static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
{
if (is_write) {
memory: Don't use memcpy for ram_device regions With a vfio assigned device we lay down a base MemoryRegion registered as an IO region, giving us read & write accessors. If the region supports mmap, we lay down a higher priority sub-region MemoryRegion on top of the base layer initialized as a RAM device pointer to the mmap. Finally, if we have any quirks for the device (ie. address ranges that need additional virtualization support), we put another IO sub-region on top of the mmap MemoryRegion. When this is flattened, we now potentially have sub-page mmap MemoryRegions exposed which cannot be directly mapped through KVM. This is as expected, but a subtle detail of this is that we end up with two different access mechanisms through QEMU. If we disable the mmap MemoryRegion, we make use of the IO MemoryRegion and service accesses using pread and pwrite to the vfio device file descriptor. If the mmap MemoryRegion is enabled and results in one of these sub-page gaps, QEMU handles the access as RAM, using memcpy to the mmap. Using either pread/pwrite or the mmap directly should be correct, but using memcpy causes us problems. I expect that not only does memcpy not necessarily honor the original width and alignment in performing a copy, but it potentially also uses processor instructions not intended for MMIO spaces. It turns out that this has been a problem for Realtek NIC assignment, which has such a quirk that creates a sub-page mmap MemoryRegion access. To resolve this, we disable memory_access_is_direct() for ram_device regions since QEMU assumes that it can use memcpy for those regions. Instead we access through MemoryRegionOps, which replaces the memcpy with simple de-references of standard sizes to the host memory. With this patch we attempt to provide unrestricted access to the RAM device, allowing byte through qword access as well as unaligned access. The assumption here is that accesses initiated by the VM are driven by a device specific driver, which knows the device capabilities. If unaligned accesses are not supported by the device, we don't want them to work in a VM by performing multiple aligned accesses to compose the unaligned access. A down-side of this philosophy is that the xp command from the monitor attempts to use the largest available access weidth, unaware of the underlying device. Using memcpy had this same restriction, but at least now an operator can dump individual registers, even if blocks of device memory may result in access widths beyond the capabilities of a given device (RTL NICs only support up to dword). Reported-by: Thorsten Kohfeldt <thorsten.kohfeldt@gmx.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31 18:53:03 +03:00
return memory_region_is_ram(mr) &&
!mr->readonly && !memory_region_is_ram_device(mr);
} else {
memory: Don't use memcpy for ram_device regions With a vfio assigned device we lay down a base MemoryRegion registered as an IO region, giving us read & write accessors. If the region supports mmap, we lay down a higher priority sub-region MemoryRegion on top of the base layer initialized as a RAM device pointer to the mmap. Finally, if we have any quirks for the device (ie. address ranges that need additional virtualization support), we put another IO sub-region on top of the mmap MemoryRegion. When this is flattened, we now potentially have sub-page mmap MemoryRegions exposed which cannot be directly mapped through KVM. This is as expected, but a subtle detail of this is that we end up with two different access mechanisms through QEMU. If we disable the mmap MemoryRegion, we make use of the IO MemoryRegion and service accesses using pread and pwrite to the vfio device file descriptor. If the mmap MemoryRegion is enabled and results in one of these sub-page gaps, QEMU handles the access as RAM, using memcpy to the mmap. Using either pread/pwrite or the mmap directly should be correct, but using memcpy causes us problems. I expect that not only does memcpy not necessarily honor the original width and alignment in performing a copy, but it potentially also uses processor instructions not intended for MMIO spaces. It turns out that this has been a problem for Realtek NIC assignment, which has such a quirk that creates a sub-page mmap MemoryRegion access. To resolve this, we disable memory_access_is_direct() for ram_device regions since QEMU assumes that it can use memcpy for those regions. Instead we access through MemoryRegionOps, which replaces the memcpy with simple de-references of standard sizes to the host memory. With this patch we attempt to provide unrestricted access to the RAM device, allowing byte through qword access as well as unaligned access. The assumption here is that accesses initiated by the VM are driven by a device specific driver, which knows the device capabilities. If unaligned accesses are not supported by the device, we don't want them to work in a VM by performing multiple aligned accesses to compose the unaligned access. A down-side of this philosophy is that the xp command from the monitor attempts to use the largest available access weidth, unaware of the underlying device. Using memcpy had this same restriction, but at least now an operator can dump individual registers, even if blocks of device memory may result in access widths beyond the capabilities of a given device (RTL NICs only support up to dword). Reported-by: Thorsten Kohfeldt <thorsten.kohfeldt@gmx.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31 18:53:03 +03:00
return (memory_region_is_ram(mr) && !memory_region_is_ram_device(mr)) ||
memory_region_is_romd(mr);
}
}
/**
* address_space_read: read from an address space.
*
* Return a MemTxResult indicating whether the operation succeeded
* or failed (eg unassigned memory, device rejected the transaction,
* IOMMU fault). Called within RCU critical section.
*
* @as: #AddressSpace to be accessed
* @addr: address within that address space
* @attrs: memory transaction attributes
* @buf: buffer with the data transferred
*/
static inline __attribute__((__always_inline__))
MemTxResult address_space_read(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf,
int len)
{
MemTxResult result = MEMTX_OK;
hwaddr l, addr1;
void *ptr;
MemoryRegion *mr;
FlatView *fv;
if (__builtin_constant_p(len)) {
if (len) {
rcu_read_lock();
fv = address_space_to_flatview(as);
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false);
if (len == l && memory_access_is_direct(mr, false)) {
ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
memcpy(buf, ptr, len);
} else {
result = flatview_read_continue(fv, addr, attrs, buf, len,
addr1, l, mr);
}
rcu_read_unlock();
}
} else {
result = address_space_read_full(as, addr, attrs, buf, len);
}
return result;
}
/**
* address_space_read_cached: read from a cached RAM region
*
* @cache: Cached region to be addressed
* @addr: address relative to the base of the RAM region
* @buf: buffer with the data transferred
* @len: length of the data transferred
*/
static inline void
address_space_read_cached(MemoryRegionCache *cache, hwaddr addr,
void *buf, int len)
{
assert(addr < cache->len && len <= cache->len - addr);
address_space_read(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len);
}
/**
* address_space_write_cached: write to a cached RAM region
*
* @cache: Cached region to be addressed
* @addr: address relative to the base of the RAM region
* @buf: buffer with the data transferred
* @len: length of the data transferred
*/
static inline void
address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
void *buf, int len)
{
assert(addr < cache->len && len <= cache->len - addr);
address_space_write(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len);
}
#endif
#endif