OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity
8e0932802f
qemu-e2k/include/exec/memory.h
Steve Sistare b0182e537e exec/memory: Introduce RAM_NAMED_FILE flag 
migrate_ignore_shared() is an optimization that avoids copying memory
that is visible and can be mapped on the target.  However, a
memory-backend-ram or a memory-backend-memfd block with the RAM_SHARED
flag set is not migrated when migrate_ignore_shared() is true.  This is
wrong, because the block has no named backing store, and its contents will
be lost.  To fix, ignore shared memory iff it is a named file.  Define a
new flag RAM_NAMED_FILE to distinguish this case.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1686151116-253260-1-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-13 11:28:58 +02:00

3070 lines
112 KiB
C
Raw Blame History

/*
* 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/memop.h"
#include "exec/ramlist.h"
#include "qemu/bswap.h"
#include "qemu/queue.h"
#include "qemu/int128.h"
#include "qemu/notify.h"
#include "qom/object.h"
#include "qemu/rcu.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 "memory-region"
DECLARE_INSTANCE_CHECKER(MemoryRegion, MEMORY_REGION,
TYPE_MEMORY_REGION)
#define TYPE_IOMMU_MEMORY_REGION "iommu-memory-region"
typedef struct IOMMUMemoryRegionClass IOMMUMemoryRegionClass;
DECLARE_OBJ_CHECKERS(IOMMUMemoryRegion, IOMMUMemoryRegionClass,
IOMMU_MEMORY_REGION, TYPE_IOMMU_MEMORY_REGION)
#define TYPE_RAM_DISCARD_MANAGER "qemu:ram-discard-manager"
typedef struct RamDiscardManagerClass RamDiscardManagerClass;
typedef struct RamDiscardManager RamDiscardManager;
DECLARE_OBJ_CHECKERS(RamDiscardManager, RamDiscardManagerClass,
RAM_DISCARD_MANAGER, TYPE_RAM_DISCARD_MANAGER);
#ifdef CONFIG_FUZZ
void fuzz_dma_read_cb(size_t addr,
size_t len,
MemoryRegion *mr);
#else
static inline void fuzz_dma_read_cb(size_t addr,
size_t len,
MemoryRegion *mr)
{
/* Do Nothing */
}
#endif
/* Possible bits for global_dirty_log_{start|stop} */
/* Dirty tracking enabled because migration is running */
#define GLOBAL_DIRTY_MIGRATION (1U << 0)
/* Dirty tracking enabled because measuring dirty rate */
#define GLOBAL_DIRTY_DIRTY_RATE (1U << 1)
/* Dirty tracking enabled because dirty limit */
#define GLOBAL_DIRTY_LIMIT (1U << 2)
#define GLOBAL_DIRTY_MASK (0x7)
extern unsigned int global_dirty_tracking;
typedef struct MemoryRegionOps MemoryRegionOps;
struct ReservedRegion {
hwaddr low;
hwaddr high;
unsigned type;
};
/**
* struct 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
* @nonvolatile: this section is non-volatile
*/
struct MemoryRegionSection {
Int128 size;
MemoryRegion *mr;
FlatView *fv;
hwaddr offset_within_region;
hwaddr offset_within_address_space;
bool readonly;
bool nonvolatile;
};
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).
*
* Normally there're two use cases for the notifiers:
*
* (1) When the device needs accurate synchronizations of the vIOMMU page
* tables, it needs to register with both MAP|UNMAP notifies (which
* is defined as IOMMU_NOTIFIER_IOTLB_EVENTS below).
*
* Regarding to accurate synchronization, it's when the notified
* device maintains a shadow page table and must be notified on each
* guest MAP (page table entry creation) and UNMAP (invalidation)
* events (e.g. VFIO). Both notifications must be accurate so that
* the shadow page table is fully in sync with the guest view.
*
* (2) When the device doesn't need accurate synchronizations of the
* vIOMMU page tables, it needs to register only with UNMAP or
* DEVIOTLB_UNMAP notifies.
*
* It's when the device maintains a cache of IOMMU translations
* (IOTLB) and is able to fill that cache by requesting translations
* from the vIOMMU through a protocol similar to ATS (Address
* Translation Service).
*
* Note that in this mode the vIOMMU will not maintain a shadowed
* page table for the address space, and the UNMAP messages can cover
* more than the pages that used to get mapped. The IOMMU notifiee
* should be able to take care of over-sized invalidations.
*/
typedef enum {
IOMMU_NOTIFIER_NONE = 0,
/* Notify cache invalidations */
IOMMU_NOTIFIER_UNMAP = 0x1,
/* Notify entry changes (newly created entries) */
IOMMU_NOTIFIER_MAP = 0x2,
/* Notify changes on device IOTLB entries */
IOMMU_NOTIFIER_DEVIOTLB_UNMAP = 0x04,
} IOMMUNotifierFlag;
#define IOMMU_NOTIFIER_IOTLB_EVENTS (IOMMU_NOTIFIER_MAP | IOMMU_NOTIFIER_UNMAP)
#define IOMMU_NOTIFIER_DEVIOTLB_EVENTS IOMMU_NOTIFIER_DEVIOTLB_UNMAP
#define IOMMU_NOTIFIER_ALL (IOMMU_NOTIFIER_IOTLB_EVENTS | \
IOMMU_NOTIFIER_DEVIOTLB_EVENTS)
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;
int iommu_idx;
QLIST_ENTRY(IOMMUNotifier) node;
};
typedef struct IOMMUNotifier IOMMUNotifier;
typedef struct IOMMUTLBEvent {
IOMMUNotifierFlag type;
IOMMUTLBEntry entry;
} IOMMUTLBEvent;
/* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */
#define RAM_PREALLOC (1 << 0)
/* RAM is mmap-ed with MAP_SHARED */
#define RAM_SHARED (1 << 1)
/* Only a portion of RAM (used_length) is actually used, and migrated.
* Resizing RAM while migrating can result in the migration being canceled.
*/
#define RAM_RESIZEABLE (1 << 2)
/* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically
* zero the page and wake waiting processes.
* (Set during postcopy)
*/
#define RAM_UF_ZEROPAGE (1 << 3)
/* RAM can be migrated */
#define RAM_MIGRATABLE (1 << 4)
/* RAM is a persistent kind memory */
#define RAM_PMEM (1 << 5)
/*
* UFFDIO_WRITEPROTECT is used on this RAMBlock to
* support 'write-tracking' migration type.
* Implies ram_state->ram_wt_enabled.
*/
#define RAM_UF_WRITEPROTECT (1 << 6)
/*
* RAM is mmap-ed with MAP_NORESERVE. When set, reserving swap space (or huge
* pages if applicable) is skipped: will bail out if not supported. When not
* set, the OS will do the reservation, if supported for the memory type.
*/
#define RAM_NORESERVE (1 << 7)
/* RAM that isn't accessible through normal means. */
#define RAM_PROTECTED (1 << 8)
/* RAM is an mmap-ed named file */
#define RAM_NAMED_FILE (1 << 9)
static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
IOMMUNotifierFlag flags,
hwaddr start, hwaddr end,
int iommu_idx)
{
n->notify = fn;
n->notifier_flags = flags;
n->start = start;
n->end = end;
n->iommu_idx = iommu_idx;
}
/*
* 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);
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,
MemTxAttrs attrs);
} 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;
};
typedef struct MemoryRegionClass {
/* private */
ObjectClass parent_class;
} MemoryRegionClass;
enum IOMMUMemoryRegionAttr {
IOMMU_ATTR_SPAPR_TCE_FD
};
/*
* IOMMUMemoryRegionClass:
*
* All IOMMU implementations need to subclass TYPE_IOMMU_MEMORY_REGION
* and provide an implementation of at least the @translate method here
* to handle requests to the memory region. Other methods are optional.
*
* The IOMMU implementation must use the IOMMU notifier infrastructure
* to report whenever mappings are changed, by calling
* memory_region_notify_iommu() (or, if necessary, by calling
* memory_region_notify_iommu_one() for each registered notifier).
*
* Conceptually an IOMMU provides a mapping from input address
* to an output TLB entry. If the IOMMU is aware of memory transaction
* attributes and the output TLB entry depends on the transaction
* attributes, we represent this using IOMMU indexes. Each index
* selects a particular translation table that the IOMMU has:
*
* @attrs_to_index returns the IOMMU index for a set of transaction attributes
*
* @translate takes an input address and an IOMMU index
*
* and the mapping returned can only depend on the input address and the
* IOMMU index.
*
* Most IOMMUs don't care about the transaction attributes and support
* only a single IOMMU index. A more complex IOMMU might have one index
* for secure transactions and one for non-secure transactions.
*/
struct IOMMUMemoryRegionClass {
/* private: */
MemoryRegionClass parent_class;
/* public: */
/**
* @translate:
*
* Return a TLB entry that contains a given address.
*
* The IOMMUAccessFlags indicated via @flag are optional and may
* be specified as IOMMU_NONE to indicate that the caller needs
* the full translation information for both reads and writes. If
* the access flags are specified then the IOMMU implementation
* may use this as an optimization, to stop doing a page table
* walk as soon as it knows that the requested permissions are not
* allowed. If IOMMU_NONE is passed then the IOMMU must do the
* full page table walk and report the permissions in the returned
* IOMMUTLBEntry. (Note that this implies that an IOMMU may not
* return different mappings for reads and writes.)
*
* The returned information remains valid while the caller is
* holding the big QEMU lock or is inside an RCU critical section;
* if the caller wishes to cache the mapping beyond that it must
* register an IOMMU notifier so it can invalidate its cached
* information when the IOMMU mapping changes.
*
* @iommu: the IOMMUMemoryRegion
*
* @hwaddr: address to be translated within the memory region
*
* @flag: requested access permission
*
* @iommu_idx: IOMMU index for the translation
*/
IOMMUTLBEntry (*translate)(IOMMUMemoryRegion *iommu, hwaddr addr,
IOMMUAccessFlags flag, int iommu_idx);
/**
* @get_min_page_size:
*
* Returns minimum supported page size in bytes.
*
* If this method is not provided then the minimum is assumed to
* be TARGET_PAGE_SIZE.
*
* @iommu: the IOMMUMemoryRegion
*/
uint64_t (*get_min_page_size)(IOMMUMemoryRegion *iommu);
/**
* @notify_flag_changed:
*
* Called when IOMMU Notifier flag changes (ie when the set of
* events which IOMMU users are requesting notification for changes).
* Optional method -- need not be provided if the IOMMU does not
* need to know exactly which events must be notified.
*
* @iommu: the IOMMUMemoryRegion
*
* @old_flags: events which previously needed to be notified
*
* @new_flags: events which now need to be notified
*
* Returns 0 on success, or a negative errno; in particular
* returns -EINVAL if the new flag bitmap is not supported by the
* IOMMU memory region. In case of failure, the error object
* must be created
*/
int (*notify_flag_changed)(IOMMUMemoryRegion *iommu,
IOMMUNotifierFlag old_flags,
IOMMUNotifierFlag new_flags,
Error **errp);
/**
* @replay:
*
* Called to handle memory_region_iommu_replay().
*
* The default implementation of memory_region_iommu_replay() is to
* call the IOMMU translate method for every page in the address space
* with flag == IOMMU_NONE and then call the notifier if translate
* returns a valid mapping. If this method is implemented then it
* overrides the default behaviour, and must provide the full semantics
* of memory_region_iommu_replay(), by calling @notifier for every
* translation present in the IOMMU.
*
* Optional method -- an IOMMU only needs to provide this method
* if the default is inefficient or produces undesirable side effects.
*
* Note: this is not related to record-and-replay functionality.
*/
void (*replay)(IOMMUMemoryRegion *iommu, IOMMUNotifier *notifier);
/**
* @get_attr:
*
* Get IOMMU misc attributes. This is an optional method that
* can be used to allow users of the IOMMU to get implementation-specific
* information. The IOMMU implements this method to handle calls
* by IOMMU users to memory_region_iommu_get_attr() by filling in
* the arbitrary data pointer for any IOMMUMemoryRegionAttr values that
* the IOMMU supports. If the method is unimplemented then
* memory_region_iommu_get_attr() will always return -EINVAL.
*
* @iommu: the IOMMUMemoryRegion
*
* @attr: attribute being queried
*
* @data: memory to fill in with the attribute data
*
* Returns 0 on success, or a negative errno; in particular
* returns -EINVAL for unrecognized or unimplemented attribute types.
*/
int (*get_attr)(IOMMUMemoryRegion *iommu, enum IOMMUMemoryRegionAttr attr,
void *data);
/**
* @attrs_to_index:
*
* Return the IOMMU index to use for a given set of transaction attributes.
*
* Optional method: if an IOMMU only supports a single IOMMU index then
* the default implementation of memory_region_iommu_attrs_to_index()
* will return 0.
*
* The indexes supported by an IOMMU must be contiguous, starting at 0.
*
* @iommu: the IOMMUMemoryRegion
* @attrs: memory transaction attributes
*/
int (*attrs_to_index)(IOMMUMemoryRegion *iommu, MemTxAttrs attrs);
/**
* @num_indexes:
*
* Return the number of IOMMU indexes this IOMMU supports.
*
* Optional method: if this method is not provided, then
* memory_region_iommu_num_indexes() will return 1, indicating that
* only a single IOMMU index is supported.
*
* @iommu: the IOMMUMemoryRegion
*/
int (*num_indexes)(IOMMUMemoryRegion *iommu);
/**
* @iommu_set_page_size_mask:
*
* Restrict the page size mask that can be supported with a given IOMMU
* memory region. Used for example to propagate host physical IOMMU page
* size mask limitations to the virtual IOMMU.
*
* Optional method: if this method is not provided, then the default global
* page mask is used.
*
* @iommu: the IOMMUMemoryRegion
*
* @page_size_mask: a bitmask of supported page sizes. At least one bit,
* representing the smallest page size, must be set. Additional set bits
* represent supported block sizes. For example a host physical IOMMU that
* uses page tables with a page size of 4kB, and supports 2MB and 4GB
* blocks, will set mask 0x40201000. A granule of 4kB with indiscriminate
* block sizes is specified with mask 0xfffffffffffff000.
*
* Returns 0 on success, or a negative error. In case of failure, the error
* object must be created.
*/
int (*iommu_set_page_size_mask)(IOMMUMemoryRegion *iommu,
uint64_t page_size_mask,
Error **errp);
};
typedef struct RamDiscardListener RamDiscardListener;
typedef int (*NotifyRamPopulate)(RamDiscardListener *rdl,
MemoryRegionSection *section);
typedef void (*NotifyRamDiscard)(RamDiscardListener *rdl,
MemoryRegionSection *section);
struct RamDiscardListener {
/*
* @notify_populate:
*
* Notification that previously discarded memory is about to get populated.
* Listeners are able to object. If any listener objects, already
* successfully notified listeners are notified about a discard again.
*
* @rdl: the #RamDiscardListener getting notified
* @section: the #MemoryRegionSection to get populated. The section
* is aligned within the memory region to the minimum granularity
* unless it would exceed the registered section.
*
* Returns 0 on success. If the notification is rejected by the listener,
* an error is returned.
*/
NotifyRamPopulate notify_populate;
/*
* @notify_discard:
*
* Notification that previously populated memory was discarded successfully
* and listeners should drop all references to such memory and prevent
* new population (e.g., unmap).
*
* @rdl: the #RamDiscardListener getting notified
* @section: the #MemoryRegionSection to get populated. The section
* is aligned within the memory region to the minimum granularity
* unless it would exceed the registered section.
*/
NotifyRamDiscard notify_discard;
/*
* @double_discard_supported:
*
* The listener suppors getting @notify_discard notifications that span
* already discarded parts.
*/
bool double_discard_supported;
MemoryRegionSection *section;
QLIST_ENTRY(RamDiscardListener) next;
};
static inline void ram_discard_listener_init(RamDiscardListener *rdl,
NotifyRamPopulate populate_fn,
NotifyRamDiscard discard_fn,
bool double_discard_supported)
{
rdl->notify_populate = populate_fn;
rdl->notify_discard = discard_fn;
rdl->double_discard_supported = double_discard_supported;
}
typedef int (*ReplayRamPopulate)(MemoryRegionSection *section, void *opaque);
typedef void (*ReplayRamDiscard)(MemoryRegionSection *section, void *opaque);
/*
* RamDiscardManagerClass:
*
* A #RamDiscardManager coordinates which parts of specific RAM #MemoryRegion
* regions are currently populated to be used/accessed by the VM, notifying
* after parts were discarded (freeing up memory) and before parts will be
* populated (consuming memory), to be used/accessed by the VM.
*
* A #RamDiscardManager can only be set for a RAM #MemoryRegion while the
* #MemoryRegion isn't mapped yet; it cannot change while the #MemoryRegion is
* mapped.
*
* The #RamDiscardManager is intended to be used by technologies that are
* incompatible with discarding of RAM (e.g., VFIO, which may pin all
* memory inside a #MemoryRegion), and require proper coordination to only
* map the currently populated parts, to hinder parts that are expected to
* remain discarded from silently getting populated and consuming memory.
* Technologies that support discarding of RAM don't have to bother and can
* simply map the whole #MemoryRegion.
*
* An example #RamDiscardManager is virtio-mem, which logically (un)plugs
* memory within an assigned RAM #MemoryRegion, coordinated with the VM.
* Logically unplugging memory consists of discarding RAM. The VM agreed to not
* access unplugged (discarded) memory - especially via DMA. virtio-mem will
* properly coordinate with listeners before memory is plugged (populated),
* and after memory is unplugged (discarded).
*
* Listeners are called in multiples of the minimum granularity (unless it
* would exceed the registered range) and changes are aligned to the minimum
* granularity within the #MemoryRegion. Listeners have to prepare for memory
* becoming discarded in a different granularity than it was populated and the
* other way around.
*/
struct RamDiscardManagerClass {
/* private */
InterfaceClass parent_class;
/* public */
/**
* @get_min_granularity:
*
* Get the minimum granularity in which listeners will get notified
* about changes within the #MemoryRegion via the #RamDiscardManager.
*
* @rdm: the #RamDiscardManager
* @mr: the #MemoryRegion
*
* Returns the minimum granularity.
*/
uint64_t (*get_min_granularity)(const RamDiscardManager *rdm,
const MemoryRegion *mr);
/**
* @is_populated:
*
* Check whether the given #MemoryRegionSection is completely populated
* (i.e., no parts are currently discarded) via the #RamDiscardManager.
* There are no alignment requirements.
*
* @rdm: the #RamDiscardManager
* @section: the #MemoryRegionSection
*
* Returns whether the given range is completely populated.
*/
bool (*is_populated)(const RamDiscardManager *rdm,
const MemoryRegionSection *section);
/**
* @replay_populated:
*
* Call the #ReplayRamPopulate callback for all populated parts within the
* #MemoryRegionSection via the #RamDiscardManager.
*
* In case any call fails, no further calls are made.
*
* @rdm: the #RamDiscardManager
* @section: the #MemoryRegionSection
* @replay_fn: the #ReplayRamPopulate callback
* @opaque: pointer to forward to the callback
*
* Returns 0 on success, or a negative error if any notification failed.
*/
int (*replay_populated)(const RamDiscardManager *rdm,
MemoryRegionSection *section,
ReplayRamPopulate replay_fn, void *opaque);
/**
* @replay_discarded:
*
* Call the #ReplayRamDiscard callback for all discarded parts within the
* #MemoryRegionSection via the #RamDiscardManager.
*
* @rdm: the #RamDiscardManager
* @section: the #MemoryRegionSection
* @replay_fn: the #ReplayRamDiscard callback
* @opaque: pointer to forward to the callback
*/
void (*replay_discarded)(const RamDiscardManager *rdm,
MemoryRegionSection *section,
ReplayRamDiscard replay_fn, void *opaque);
/**
* @register_listener:
*
* Register a #RamDiscardListener for the given #MemoryRegionSection and
* immediately notify the #RamDiscardListener about all populated parts
* within the #MemoryRegionSection via the #RamDiscardManager.
*
* In case any notification fails, no further notifications are triggered
* and an error is logged.
*
* @rdm: the #RamDiscardManager
* @rdl: the #RamDiscardListener
* @section: the #MemoryRegionSection
*/
void (*register_listener)(RamDiscardManager *rdm,
RamDiscardListener *rdl,
MemoryRegionSection *section);
/**
* @unregister_listener:
*
* Unregister a previously registered #RamDiscardListener via the
* #RamDiscardManager after notifying the #RamDiscardListener about all
* populated parts becoming unpopulated within the registered
* #MemoryRegionSection.
*
* @rdm: the #RamDiscardManager
* @rdl: the #RamDiscardListener
*/
void (*unregister_listener)(RamDiscardManager *rdm,
RamDiscardListener *rdl);
};
uint64_t ram_discard_manager_get_min_granularity(const RamDiscardManager *rdm,
const MemoryRegion *mr);
bool ram_discard_manager_is_populated(const RamDiscardManager *rdm,
const MemoryRegionSection *section);
int ram_discard_manager_replay_populated(const RamDiscardManager *rdm,
MemoryRegionSection *section,
ReplayRamPopulate replay_fn,
void *opaque);
void ram_discard_manager_replay_discarded(const RamDiscardManager *rdm,
MemoryRegionSection *section,
ReplayRamDiscard replay_fn,
void *opaque);
void ram_discard_manager_register_listener(RamDiscardManager *rdm,
RamDiscardListener *rdl,
MemoryRegionSection *section);
void ram_discard_manager_unregister_listener(RamDiscardManager *rdm,
RamDiscardListener *rdl);
bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
ram_addr_t *ram_addr, bool *read_only,
bool *mr_has_discard_manager);
typedef struct CoalescedMemoryRange CoalescedMemoryRange;
typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
/** MemoryRegion:
*
* A struct representing a memory region.
*/
struct MemoryRegion {
Object parent_obj;
/* private: */
/* The following fields should fit in a cache line */
bool romd_mode;
bool ram;
bool subpage;
bool readonly; /* For RAM regions */
bool nonvolatile;
bool rom_device;
bool flush_coalesced_mmio;
uint8_t dirty_log_mask;
bool is_iommu;
RAMBlock *ram_block;
Object *owner;
/* owner as TYPE_DEVICE. Used for re-entrancy checks in MR access hotpath */
DeviceState *dev;
const MemoryRegionOps *ops;
void *opaque;
MemoryRegion *container;
int mapped_via_alias; /* Mapped via an alias, container might be NULL */
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(, MemoryRegion) subregions;
QTAILQ_ENTRY(MemoryRegion) subregions_link;
QTAILQ_HEAD(, CoalescedMemoryRange) coalesced;
const char *name;
unsigned ioeventfd_nb;
MemoryRegionIoeventfd *ioeventfds;
RamDiscardManager *rdm; /* Only for RAM */
/* For devices designed to perform re-entrant IO into their own IO MRs */
bool disable_reentrancy_guard;
};
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)
/**
* struct 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 {
/**
* @begin:
*
* Called at the beginning of an address space update transaction.
* Followed by calls to #MemoryListener.region_add(),
* #MemoryListener.region_del(), #MemoryListener.region_nop(),
* #MemoryListener.log_start() and #MemoryListener.log_stop() in
* increasing address order.
*
* @listener: The #MemoryListener.
*/
void (*begin)(MemoryListener *listener);
/**
* @commit:
*
* Called at the end of an address space update transaction,
* after the last call to #MemoryListener.region_add(),
* #MemoryListener.region_del() or #MemoryListener.region_nop(),
* #MemoryListener.log_start() and #MemoryListener.log_stop().
*
* @listener: The #MemoryListener.
*/
void (*commit)(MemoryListener *listener);
/**
* @region_add:
*
* Called during an address space update transaction,
* for a section of the address space that is new in this address space
* space since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The new #MemoryRegionSection.
*/
void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
/**
* @region_del:
*
* Called during an address space update transaction,
* for a section of the address space that has disappeared in the address
* space since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The old #MemoryRegionSection.
*/
void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
/**
* @region_nop:
*
* Called during an address space update transaction,
* for a section of the address space that is in the same place in the address
* space as in the last transaction.
*
* @listener: The #MemoryListener.
* @section: The #MemoryRegionSection.
*/
void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
/**
* @log_start:
*
* Called during an address space update transaction, after
* one of #MemoryListener.region_add(), #MemoryListener.region_del() or
* #MemoryListener.region_nop(), if dirty memory logging clients have
* become active since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The #MemoryRegionSection.
* @old: A bitmap of dirty memory logging clients that were active in
* the previous transaction.
* @new: A bitmap of dirty memory logging clients that are active in
* the current transaction.
*/
void (*log_start)(MemoryListener *listener, MemoryRegionSection *section,
int old, int new);
/**
* @log_stop:
*
* Called during an address space update transaction, after
* one of #MemoryListener.region_add(), #MemoryListener.region_del() or
* #MemoryListener.region_nop() and possibly after
* #MemoryListener.log_start(), if dirty memory logging clients have
* become inactive since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The #MemoryRegionSection.
* @old: A bitmap of dirty memory logging clients that were active in
* the previous transaction.
* @new: A bitmap of dirty memory logging clients that are active in
* the current transaction.
*/
void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section,
int old, int new);
/**
* @log_sync:
*
* Called by memory_region_snapshot_and_clear_dirty() and
* memory_global_dirty_log_sync(), before accessing QEMU's "official"
* copy of the dirty memory bitmap for a #MemoryRegionSection.
*
* @listener: The #MemoryListener.
* @section: The #MemoryRegionSection.
*/
void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);
/**
* @log_sync_global:
*
* This is the global version of @log_sync when the listener does
* not have a way to synchronize the log with finer granularity.
* When the listener registers with @log_sync_global defined, then
* its @log_sync must be NULL. Vice versa.
*
* @listener: The #MemoryListener.
* @last_stage: The last stage to synchronize the log during migration.
* The caller should gurantee that the synchronization with true for
* @last_stage is triggered for once after all VCPUs have been stopped.
*/
void (*log_sync_global)(MemoryListener *listener, bool last_stage);
/**
* @log_clear:
*
* Called before reading the dirty memory bitmap for a
* #MemoryRegionSection.
*
* @listener: The #MemoryListener.
* @section: The #MemoryRegionSection.
*/
void (*log_clear)(MemoryListener *listener, MemoryRegionSection *section);
/**
* @log_global_start:
*
* Called by memory_global_dirty_log_start(), which
* enables the %DIRTY_LOG_MIGRATION client on all memory regions in
* the address space. #MemoryListener.log_global_start() is also
* called when a #MemoryListener is added, if global dirty logging is
* active at that time.
*
* @listener: The #MemoryListener.
*/
void (*log_global_start)(MemoryListener *listener);
/**
* @log_global_stop:
*
* Called by memory_global_dirty_log_stop(), which
* disables the %DIRTY_LOG_MIGRATION client on all memory regions in
* the address space.
*
* @listener: The #MemoryListener.
*/
void (*log_global_stop)(MemoryListener *listener);
/**
* @log_global_after_sync:
*
* Called after reading the dirty memory bitmap
* for any #MemoryRegionSection.
*
* @listener: The #MemoryListener.
*/
void (*log_global_after_sync)(MemoryListener *listener);
/**
* @eventfd_add:
*
* Called during an address space update transaction,
* for a section of the address space that has had a new ioeventfd
* registration since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The new #MemoryRegionSection.
* @match_data: The @match_data parameter for the new ioeventfd.
* @data: The @data parameter for the new ioeventfd.
* @e: The #EventNotifier parameter for the new ioeventfd.
*/
void (*eventfd_add)(MemoryListener *listener, MemoryRegionSection *section,
bool match_data, uint64_t data, EventNotifier *e);
/**
* @eventfd_del:
*
* Called during an address space update transaction,
* for a section of the address space that has dropped an ioeventfd
* registration since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The new #MemoryRegionSection.
* @match_data: The @match_data parameter for the dropped ioeventfd.
* @data: The @data parameter for the dropped ioeventfd.
* @e: The #EventNotifier parameter for the dropped ioeventfd.
*/
void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
bool match_data, uint64_t data, EventNotifier *e);
/**
* @coalesced_io_add:
*
* Called during an address space update transaction,
* for a section of the address space that has had a new coalesced
* MMIO range registration since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The new #MemoryRegionSection.
* @addr: The starting address for the coalesced MMIO range.
* @len: The length of the coalesced MMIO range.
*/
void (*coalesced_io_add)(MemoryListener *listener, MemoryRegionSection *section,
hwaddr addr, hwaddr len);
/**
* @coalesced_io_del:
*
* Called during an address space update transaction,
* for a section of the address space that has dropped a coalesced
* MMIO range since the last transaction.
*
* @listener: The #MemoryListener.
* @section: The new #MemoryRegionSection.
* @addr: The starting address for the coalesced MMIO range.
* @len: The length of the coalesced MMIO range.
*/
void (*coalesced_io_del)(MemoryListener *listener, MemoryRegionSection *section,
hwaddr addr, hwaddr len);
/**
* @priority:
*
* Govern the order in which memory listeners are invoked. Lower priorities
* are invoked earlier for "add" or "start" callbacks, and later for "delete"
* or "stop" callbacks.
*/
unsigned priority;
/**
* @name:
*
* Name of the listener. It can be used in contexts where we'd like to
* identify one memory listener with the rest.
*/
const char *name;
/* private: */
AddressSpace *address_space;
QTAILQ_ENTRY(MemoryListener) link;
QTAILQ_ENTRY(MemoryListener) link_as;
};
/**
* struct AddressSpace: describes a mapping of addresses to #MemoryRegion objects
*/
struct AddressSpace {
/* private: */
struct rcu_head rcu;
char *name;
MemoryRegion *root;
/* Accessed via RCU. */
struct FlatView *current_map;
int ioeventfd_nb;
struct MemoryRegionIoeventfd *ioeventfds;
QTAILQ_HEAD(, 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 qatomic_rcu_read(&as->current_map);
}
/**
* typedef flatview_cb: callback for flatview_for_each_range()
*
* @start: start address of the range within the FlatView
* @len: length of the range in bytes
* @mr: MemoryRegion covering this range
* @offset_in_region: offset of the first byte of the range within @mr
* @opaque: data pointer passed to flatview_for_each_range()
*
* Returns: true to stop the iteration, false to keep going.
*/
typedef bool (*flatview_cb)(Int128 start,
Int128 len,
const MemoryRegion *mr,
hwaddr offset_in_region,
void *opaque);
/**
* flatview_for_each_range: Iterate through a FlatView
* @fv: the FlatView to iterate through
* @cb: function to call for each range
* @opaque: opaque data pointer to pass to @cb
*
* A FlatView is made up of a list of non-overlapping ranges, each of
* which is a slice of a MemoryRegion. This function iterates through
* each range in @fv, calling @cb. The callback function can terminate
* iteration early by returning 'true'.
*/
void flatview_for_each_range(FlatView *fv, flatview_cb cb, void *opaque);
static inline bool MemoryRegionSection_eq(MemoryRegionSection *a,
MemoryRegionSection *b)
{
return a->mr == b->mr &&
a->fv == b->fv &&
a->offset_within_region == b->offset_within_region &&
a->offset_within_address_space == b->offset_within_address_space &&
int128_eq(a->size, b->size) &&
a->readonly == b->readonly &&
a->nonvolatile == b->nonvolatile;
}
/**
* memory_region_section_new_copy: Copy a memory region section
*
* Allocate memory for a new copy, copy the memory region section, and
* properly take a reference on all relevant members.
*
* @s: the #MemoryRegionSection to copy
*/
MemoryRegionSection *memory_region_section_new_copy(MemoryRegionSection *s);
/**
* memory_region_section_new_copy: Free a copied memory region section
*
* Free a copy of a memory section created via memory_region_section_new_copy().
* properly dropping references on all relevant members.
*
* @s: the #MemoryRegionSection to copy
*/
void memory_region_section_free_copy(MemoryRegionSection *s);
/**
* 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,
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,
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,
Object *owner,
const char *name,
uint64_t size,
Error **errp);
/**
* memory_region_init_ram_flags_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.
* @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_NORESERVE.
* @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_flags_nomigrate(MemoryRegion *mr,
Object *owner,
const char *name,
uint64_t size,
uint32_t ram_flags,
Error **errp);
/**
* memory_region_init_resizeable_ram: Initialize memory region with resizable
* RAM. Accesses into the region will
* modify memory directly. Only an initial
* portion of this RAM is actually used.
* Changing the size while migrating
* can result in the migration being
* canceled.
*
* @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,
Object *owner,
const char *name,
uint64_t size,
uint64_t max_size,
void (*resized)(const char*,
uint64_t length,
void *host),
Error **errp);
#ifdef CONFIG_POSIX
/**
* 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.
* @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
* RAM_NORESERVE,
* @path: the path in which to allocate the RAM.
* @offset: offset within the file referenced by path
* @readonly: true to open @path for reading, false for read/write.
* @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,
Object *owner,
const char *name,
uint64_t size,
uint64_t align,
uint32_t ram_flags,
const char *path,
ram_addr_t offset,
bool readonly,
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.
* @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
* RAM_NORESERVE, RAM_PROTECTED.
* @fd: the fd to mmap.
* @offset: offset within the file referenced by fd
* @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,
Object *owner,
const char *name,
uint64_t size,
uint32_t ram_flags,
int fd,
ram_addr_t offset,
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,
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,
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,
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,
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,
Object *owner,
const MemoryRegionOps *ops,
void *opaque,
const char *name,
uint64_t size,
Error **errp);
/**
* 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.
*
* The IOMMU implementation must define a subclass of TYPE_IOMMU_MEMORY_REGION.
* @_iommu_mr should be a pointer to enough memory for an instance of
* that subclass, @instance_size is the size of that subclass, and
* @mrtypename is its name. This function will initialize @_iommu_mr as an
* instance of the subclass, and its methods will then be called to handle
* accesses to the memory region. See the documentation of
* #IOMMUMemoryRegionClass for further details.
*
* @_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,
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,
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).
* @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(MemoryRegion *mr,
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.
*/
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 if 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 if 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_is_protected: check whether a memory region is protected
*
* Returns %true if a memory region is protected RAM and cannot be accessed
* via standard mechanisms, e.g. DMA.
*
* @mr: the memory region being queried
*/
bool memory_region_is_protected(MemoryRegion *mr);
/**
* 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.
*
* @iommu_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.
*
* 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
* @iommu_idx: the IOMMU index for the translation table which has changed
* @event: TLB event with the new entry in the IOMMU translation table.
* The entry replaces all old entries for the same virtual I/O address
* range.
*/
void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
int iommu_idx,
IOMMUTLBEvent event);
/**
* memory_region_notify_iommu_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
* @event: TLB event with the new entry in the IOMMU translation table.
* The entry replaces all old entries for the same virtual I/O address
* range.
*/
void memory_region_notify_iommu_one(IOMMUNotifier *notifier,
IOMMUTLBEvent *event);
/**
* memory_region_unmap_iommu_notifier_range: notify a unmap for an IOMMU
* translation that covers the
* range of a notifier
*
* @notifier: the notifier to be notified
*/
void memory_region_unmap_iommu_notifier_range(IOMMUNotifier *notifier);
/**
* memory_region_register_iommu_notifier: register a notifier for changes to
* IOMMU translation entries.
*
* Returns 0 on success, or a negative errno otherwise. In particular,
* -EINVAL indicates that at least one of the attributes of the notifier
* is not supported (flag/range) by the IOMMU memory region. In case of error
* the error object must be created.
*
* @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.
* @errp: pointer to Error*, to store an error if it happens.
*/
int memory_region_register_iommu_notifier(MemoryRegion *mr,
IOMMUNotifier *n, Error **errp);
/**
* memory_region_iommu_replay: replay existing IOMMU translations to
* a notifier with the minimum page granularity returned by
* mr->iommu_ops->get_page_size().
*
* Note: this is not related to record-and-replay functionality.
*
* @iommu_mr: the memory region to observe
* @n: the notifier to which to replay iommu mappings
*/
void memory_region_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n);
/**
* 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 on success, or a negative errno otherwise. In particular,
* -EINVAL indicates that the IOMMU does not support the requested
* attribute.
*
* @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_iommu_attrs_to_index: return the IOMMU index to
* use for translations with the given memory transaction attributes.
*
* @iommu_mr: the memory region
* @attrs: the memory transaction attributes
*/
int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,
MemTxAttrs attrs);
/**
* memory_region_iommu_num_indexes: return the total number of IOMMU
* indexes that this IOMMU supports.
*
* @iommu_mr: the memory region
*/
int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);
/**
* memory_region_iommu_set_page_size_mask: set the supported page
* sizes for a given IOMMU memory region
*
* @iommu_mr: IOMMU memory region
* @page_size_mask: supported page size mask
* @errp: pointer to Error*, to store an error if it happens.
*/
int memory_region_iommu_set_page_size_mask(IOMMUMemoryRegion *iommu_mr,
uint64_t page_size_mask,
Error **errp);
/**
* 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 if 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_is_nonvolatile: check whether a memory region is non-volatile
*
* Returns %true is a memory region is non-volatile memory.
*
* @mr: the memory region being queried
*/
static inline bool memory_region_is_nonvolatile(MemoryRegion *mr)
{
return mr->nonvolatile;
}
/**
* 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.
*
* Resizing RAM while migrating can result in the migration being canceled.
* Care has to be taken if the guest might have already detected the memory.
*
* @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_msync: Synchronize selected address range of
* a memory mapped region
*
* @mr: the memory region to be msync
* @addr: the initial address of the range to be sync
* @size: the size of the range to be sync
*/
void memory_region_msync(MemoryRegion *mr, hwaddr addr, hwaddr size);
/**
* memory_region_writeback: Trigger cache writeback for
* selected address range
*
* @mr: the memory region to be updated
* @addr: the initial address of the range to be written back
* @size: the size of the range to be written back
*/
void memory_region_writeback(MemoryRegion *mr, hwaddr addr, hwaddr size);
/**
* 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_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_clear_dirty_bitmap - clear dirty bitmap for memory range
*
* This function is called when the caller wants to clear the remote
* dirty bitmap of a memory range within the memory region. This can
* be used by e.g. KVM to manually clear dirty log when
* KVM_CAP_MANUAL_DIRTY_LOG_PROTECT is declared support by the host
* kernel.
*
* @mr: the memory region to clear the dirty log upon
* @start: start address offset within the memory region
* @len: length of the memory region to clear dirty bitmap
*/
void memory_region_clear_dirty_bitmap(MemoryRegion *mr, hwaddr start,
hwaddr len);
/**
* 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 copied 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_flush_rom_device: Mark a range of pages dirty and invalidate
* TBs (for self-modifying code).
*
* The MemoryRegionOps->write() callback of a ROM device must use this function
* to mark byte ranges that have been modified internally, such as by directly
* accessing the memory returned by memory_region_get_ram_ptr().
*
* This function marks the range dirty and invalidates TBs so that TCG can
* detect self-modifying code.
*
* @mr: the region being flushed.
* @addr: the start, relative to the start of the region, of the range being
* flushed.
* @size: the size, in bytes, of the range being flushed.
*/
void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr size);
/**
* 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_set_nonvolatile: Turn a memory region non-volatile
*
* Allows a memory region to be marked as non-volatile.
* only useful on RAM regions.
*
* @mr: the region being updated.
* @nonvolatile: whether rhe region is to be non-volatile.
*/
void memory_region_set_nonvolatile(MemoryRegion *mr, bool nonvolatile);
/**
* 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_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
*
* @mr: the region to be queried
*/
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 another memory region, which does not necessarily imply that it is
* mapped into an address space.
*
* @mr: a #MemoryRegion which should be checked if it's mapped
*/
bool memory_region_is_mapped(MemoryRegion *mr);
/**
* memory_region_get_ram_discard_manager: get the #RamDiscardManager for a
* #MemoryRegion
*
* The #RamDiscardManager cannot change while a memory region is mapped.
*
* @mr: the #MemoryRegion
*/
RamDiscardManager *memory_region_get_ram_discard_manager(MemoryRegion *mr);
/**
* memory_region_has_ram_discard_manager: check whether a #MemoryRegion has a
* #RamDiscardManager assigned
*
* @mr: the #MemoryRegion
*/
static inline bool memory_region_has_ram_discard_manager(MemoryRegion *mr)
{
return !!memory_region_get_ram_discard_manager(mr);
}
/**
* memory_region_set_ram_discard_manager: set the #RamDiscardManager for a
* #MemoryRegion
*
* This function must not be called for a mapped #MemoryRegion, a #MemoryRegion
* that does not cover RAM, or a #MemoryRegion that already has a
* #RamDiscardManager assigned.
*
* @mr: the #MemoryRegion
* @rdm: #RamDiscardManager to set
*/
void memory_region_set_ram_discard_manager(MemoryRegion *mr,
RamDiscardManager *rdm);
/**
* 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.
*
* @last_stage: whether this is the last stage of live migration
*/
void memory_global_dirty_log_sync(bool last_stage);
/**
* memory_global_dirty_log_sync: synchronize the dirty log for all memory
*
* Synchronizes the vCPUs with a thread that is reading the dirty bitmap.
* This function must be called after the dirty log bitmap is cleared, and
* before dirty guest memory pages are read. If you are using
* #DirtyBitmapSnapshot, memory_region_snapshot_and_clear_dirty() takes
* care of doing this.
*/
void memory_global_after_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
*
* @flags: purpose of starting dirty log, migration or dirty rate
*/
void memory_global_dirty_log_start(unsigned int flags);
/**
* memory_global_dirty_log_stop: end dirty logging for all regions
*
* @flags: purpose of stopping dirty log, migration or dirty rate
*/
void memory_global_dirty_log_stop(unsigned int flags);
void mtree_info(bool flatview, bool dispatch_tree, bool owner, bool disabled);
bool memory_region_access_valid(MemoryRegion *mr, hwaddr addr,
unsigned size, bool is_write,
MemTxAttrs attrs);
/**
* 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
* @op: size, sign, and endianness of the memory operation
* @attrs: memory transaction attributes to use for the access
*/
MemTxResult memory_region_dispatch_read(MemoryRegion *mr,
hwaddr addr,
uint64_t *pval,
MemOp op,
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
* @op: size, sign, and endianness of the memory operation
* @attrs: memory transaction attributes to use for the access
*/
MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
hwaddr addr,
uint64_t data,
MemOp op,
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_remove_listeners: unregister all listeners of an address space
*
* Removes all callbacks previously registered with memory_listener_register()
* for @as.
*
* @as: an initialized #AddressSpace
*/
void address_space_remove_listeners(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, void *buf,
hwaddr 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 void *buf, hwaddr len);
/**
* address_space_write_rom: write to address space, including ROM.
*
* This function writes to the specified address space, but will
* write data to both ROM and RAM. This is used for non-guest
* writes like writes from the gdb debug stub or initial loading
* of ROM contents.
*
* Note that portions of the write which attempt to write data to
* a device will be silently ignored -- only real RAM and ROM will
* be written to.
*
* 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_rom(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs,
const void *buf, hwaddr 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
*/
#define SUFFIX
#define ARG1 as
#define ARG1_DECL AddressSpace *as
#include "exec/memory_ldst.h.inc"
#define SUFFIX
#define ARG1 as
#define ARG1_DECL AddressSpace *as
#include "exec/memory_ldst_phys.h.inc"
struct MemoryRegionCache {
void *ptr;
hwaddr xlat;
hwaddr len;
FlatView *fv;
MemoryRegionSection mrs;
bool is_write;
};
#define MEMORY_REGION_CACHE_INVALID ((MemoryRegionCache) { .mrs.mr = NULL })
/* 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
*/
#define SUFFIX _cached_slow
#define ARG1 cache
#define ARG1_DECL MemoryRegionCache *cache
#include "exec/memory_ldst.h.inc"
/* Inline fast path for direct RAM access. */
static inline uint8_t address_space_ldub_cached(MemoryRegionCache *cache,
hwaddr addr, MemTxAttrs attrs, MemTxResult *result)
{
assert(addr < cache->len);
if (likely(cache->ptr)) {
return ldub_p(cache->ptr + addr);
} else {
return address_space_ldub_cached_slow(cache, addr, attrs, result);
}
}
static inline void address_space_stb_cached(MemoryRegionCache *cache,
hwaddr addr, uint8_t val, MemTxAttrs attrs, MemTxResult *result)
{
assert(addr < cache->len);
if (likely(cache->ptr)) {
stb_p(cache->ptr + addr, val);
} else {
address_space_stb_cached_slow(cache, addr, val, attrs, result);
}
}
#define ENDIANNESS _le
#include "exec/memory_ldst_cached.h.inc"
#define ENDIANNESS _be
#include "exec/memory_ldst_cached.h.inc"
#define SUFFIX _cached
#define ARG1 cache
#define ARG1_DECL MemoryRegionCache *cache
#include "exec/memory_ldst_phys.h.inc"
/* 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_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, MemTxAttrs attrs);
/* 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
* @attrs: memory attributes
*/
MemoryRegion *flatview_translate(FlatView *fv,
hwaddr addr, hwaddr *xlat,
hwaddr *len, bool is_write,
MemTxAttrs attrs);
static inline MemoryRegion *address_space_translate(AddressSpace *as,
hwaddr addr, hwaddr *xlat,
hwaddr *len, bool is_write,
MemTxAttrs attrs)
{
return flatview_translate(address_space_to_flatview(as),
addr, xlat, len, is_write, attrs);
}
/* 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
* @attrs: memory attributes
*/
bool address_space_access_valid(AddressSpace *as, hwaddr addr, hwaddr len,
bool is_write, MemTxAttrs attrs);
/* 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 and set *@plen to zero(0), 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
* @attrs: memory attributes
*/
void *address_space_map(AddressSpace *as, hwaddr addr,
hwaddr *plen, bool is_write, MemTxAttrs attrs);
/* 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,
bool 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, void *buf, hwaddr len);
MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, void *buf,
hwaddr len, hwaddr addr1, hwaddr l,
MemoryRegion *mr);
void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr);
/* Internal functions, part of the implementation of address_space_read_cached
* and address_space_write_cached. */
MemTxResult address_space_read_cached_slow(MemoryRegionCache *cache,
hwaddr addr, void *buf, hwaddr len);
MemTxResult address_space_write_cached_slow(MemoryRegionCache *cache,
hwaddr addr, const void *buf,
hwaddr len);
int memory_access_size(MemoryRegion *mr, unsigned l, hwaddr addr);
bool prepare_mmio_access(MemoryRegion *mr);
static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
{
if (is_write) {
return memory_region_is_ram(mr) && !mr->readonly &&
!mr->rom_device && !memory_region_is_ram_device(mr);
} else {
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
* @len: length of the data transferred
*/
static inline __attribute__((__always_inline__))
MemTxResult address_space_read(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, void *buf,
hwaddr len)
{
MemTxResult result = MEMTX_OK;
hwaddr l, addr1;
void *ptr;
MemoryRegion *mr;
FlatView *fv;
if (__builtin_constant_p(len)) {
if (len) {
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(as);
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
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);
}
}
} 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 MemTxResult
address_space_read_cached(MemoryRegionCache *cache, hwaddr addr,
void *buf, hwaddr len)
{
assert(addr < cache->len && len <= cache->len - addr);
fuzz_dma_read_cb(cache->xlat + addr, len, cache->mrs.mr);
if (likely(cache->ptr)) {
memcpy(buf, cache->ptr + addr, len);
return MEMTX_OK;
} else {
return address_space_read_cached_slow(cache, addr, 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 MemTxResult
address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
const void *buf, hwaddr len)
{
assert(addr < cache->len && len <= cache->len - addr);
if (likely(cache->ptr)) {
memcpy(cache->ptr + addr, buf, len);
return MEMTX_OK;
} else {
return address_space_write_cached_slow(cache, addr, buf, len);
}
}
/**
* address_space_set: Fill address space with a constant byte.
*
* 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
* @c: constant byte to fill the memory
* @len: the number of bytes to fill with the constant byte
* @attrs: memory transaction attributes
*/
MemTxResult address_space_set(AddressSpace *as, hwaddr addr,
uint8_t c, hwaddr len, MemTxAttrs attrs);
#ifdef NEED_CPU_H
/* enum device_endian to MemOp. */
static inline MemOp devend_memop(enum device_endian end)
{
QEMU_BUILD_BUG_ON(DEVICE_HOST_ENDIAN != DEVICE_LITTLE_ENDIAN &&
DEVICE_HOST_ENDIAN != DEVICE_BIG_ENDIAN);
#if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN
/* Swap if non-host endianness or native (target) endianness */
return (end == DEVICE_HOST_ENDIAN) ? 0 : MO_BSWAP;
#else
const int non_host_endianness =
DEVICE_LITTLE_ENDIAN ^ DEVICE_BIG_ENDIAN ^ DEVICE_HOST_ENDIAN;
/* In this case, native (target) endianness needs no swap. */
return (end == non_host_endianness) ? MO_BSWAP : 0;
#endif
}
#endif
/*
* Inhibit technologies that require discarding of pages in RAM blocks, e.g.,
* to manage the actual amount of memory consumed by the VM (then, the memory
* provided by RAM blocks might be bigger than the desired memory consumption).
* This *must* be set if:
* - Discarding parts of a RAM blocks does not result in the change being
* reflected in the VM and the pages getting freed.
* - All memory in RAM blocks is pinned or duplicated, invaldiating any previous
* discards blindly.
* - Discarding parts of a RAM blocks will result in integrity issues (e.g.,
* encrypted VMs).
* Technologies that only temporarily pin the current working set of a
* driver are fine, because we don't expect such pages to be discarded
* (esp. based on guest action like balloon inflation).
*
* This is *not* to be used to protect from concurrent discards (esp.,
* postcopy).
*
* Returns 0 if successful. Returns -EBUSY if a technology that relies on
* discards to work reliably is active.
*/
int ram_block_discard_disable(bool state);
/*
* See ram_block_discard_disable(): only disable uncoordinated discards,
* keeping coordinated discards (via the RamDiscardManager) enabled.
*/
int ram_block_uncoordinated_discard_disable(bool state);
/*
* Inhibit technologies that disable discarding of pages in RAM blocks.
*
* Returns 0 if successful. Returns -EBUSY if discards are already set to
* broken.
*/
int ram_block_discard_require(bool state);
/*
* See ram_block_discard_require(): only inhibit technologies that disable
* uncoordinated discarding of pages in RAM blocks, allowing co-existance with
* technologies that only inhibit uncoordinated discards (via the
* RamDiscardManager).
*/
int ram_block_coordinated_discard_require(bool state);
/*
* Test if any discarding of memory in ram blocks is disabled.
*/
bool ram_block_discard_is_disabled(void);
/*
* Test if any discarding of memory in ram blocks is required to work reliably.
*/
bool ram_block_discard_is_required(void);
#endif
#endif
Reference in New Issue View Git Blame Copy Permalink