/*
* Copyright (c) 2023 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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* Please see the License for the specific language governing rights and
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*/
#ifndef __VM_RECLAIM_XNU__
#define __VM_RECLAIM_XNU__
#if XNU_KERNEL_PRIVATE
#if CONFIG_DEFERRED_RECLAIM
#include <mach/mach_types.h>
#if BSD_KERNEL_PRIVATE
#include <mach/mach_vm.h>
#else /* BSD_KERNEL_PRIVATE */
#include <mach/mach_vm_server.h>
#endif /* BSD_KERNEL_PRIVATE */
typedef struct vm_deferred_reclamation_metadata_s *vm_deferred_reclamation_metadata_t;
__enum_closed_decl(vm_deferred_reclamation_gc_action_t, uint8_t, {
/* Trim all buffers */
RECLAIM_GC_TRIM = 0,
/* Fully drain all buffers */
RECLAIM_GC_DRAIN = 1,
/* Drain any buffers belonging to suspended tasks */
RECLAIM_GC_SCAVENGE = 2,
});
__options_closed_decl(vm_deferred_reclamation_options_t, uint8_t, {
RECLAIM_OPTIONS_NONE = 0x00,
/* Do not fault on the reclaim buffer if it is not resident */
RECLAIM_NO_FAULT = 0x01,
/* Do not wait to acquire the buffer if it is owned by another thread */
RECLAIM_NO_WAIT = 0x02,
});
/*
* Deallocate the kernel metadata associated with this reclamation buffer
* Note that this does NOT free the memory in the buffer.
* This is called from the task_destroy path, so we're about to reclaim all of the task's memory
* anyways.
*/
void vm_deferred_reclamation_buffer_deallocate(vm_deferred_reclamation_metadata_t metadata);
/*
* Synchronously drain all reclamation ring's belonging to a task.
*/
kern_return_t vm_deferred_reclamation_task_drain(
task_t task,
vm_deferred_reclamation_options_t options);
/*
* Return true if this task has a reclamation ring
*/
bool vm_deferred_reclamation_task_has_ring(task_t task);
/*
* Create a fork of the given reclamation buffer for a new task.
* Parent buffer must be locked and will be unlocked on return.
*
* This must be called when forking a task that has a reclamation buffer
* to duplicate the parent's buffer, and the new buffer must later be
* registered by vm_deferred_reclamation_task_fork_register.
*
* The caller must lock the parent's reclamation buffer BEFORE forking
* the parent's vm_map. Otherwise the parent's buffer could get reclaimed
* in between the map fork and the buffer fork causing the child's
* data strucutres to be out of sync.
*/
vm_deferred_reclamation_metadata_t vm_deferred_reclamation_task_fork(
task_t task,
vm_deferred_reclamation_metadata_t parent);
/*
* Add a reclamation buffer returned by vm_deferred_reclamation_task_fork to
* the global reclamation queues.
*
* The child task should call this to ensure that the kernel knows about its
* reclamation buffer. This must happen after the child's address space is
* fully initialized and able to recieve VM API calls.
*/
void
vm_deferred_reclamation_task_fork_register(vm_deferred_reclamation_metadata_t metadata);
/*
* Set the current thread as the owner of a reclaim buffer. May block. Will
* propagate priority. Should be called before forking the owning task.
*/
void vm_deferred_reclamation_ring_own(vm_deferred_reclamation_metadata_t metadata);
/*
* Release ownership of a reclaim buffer and wakeup any threads waiting for
* ownership. Must be called from the thread that acquired ownership.
*/
void vm_deferred_reclamation_ring_disown(vm_deferred_reclamation_metadata_t metadata);
/*
* Should be called when a task is suspended -- will trigger asynchronous
* reclamation of any reclaim rings owned by the task.
*/
void vm_deferred_reclamation_task_suspend(task_t task);
/*
* Perform Garbage Collection on all reclaim rings
*/
void vm_deferred_reclamation_gc(vm_deferred_reclamation_gc_action_t action,
mach_vm_size_t *total_bytes_reclaimed_out,
vm_deferred_reclamation_options_t options);
/*
* Settle ledger entry for reclaimable memory
*/
void vm_deferred_reclamation_settle_ledger(task_t task);
#endif /* CONFIG_DEFERRED_RECLAIM */
#endif /* XNU_KERNEL_PRIVATE */
#endif /* __VM_RECLAIM_XNU__ */