/*-
* SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU)
*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $FreeBSD$
*/
/*
* Resident memory system definitions.
*/
#ifndef _VM_PAGE_
#define _VM_PAGE_
#include <vm/pmap.h>
/*
* Management of resident (logical) pages.
*
* A small structure is kept for each resident
* page, indexed by page number. Each structure
* is an element of several collections:
*
* A radix tree used to quickly
* perform object/offset lookups
*
* A list of all pages for a given object,
* so they can be quickly deactivated at
* time of deallocation.
*
* An ordered list of pages due for pageout.
*
* In addition, the structure contains the object
* and offset to which this page belongs (for pageout),
* and sundry status bits.
*
* In general, operations on this structure's mutable fields are
* synchronized using either one of or a combination of the lock on the
* object that the page belongs to (O), the page lock (P),
* the per-domain lock for the free queues (F), or the page's queue
* lock (Q). The physical address of a page is used to select its page
* lock from a pool. The queue lock for a page depends on the value of
* its queue field and described in detail below. If a field is
* annotated below with two of these locks, then holding either lock is
* sufficient for read access, but both locks are required for write
* access. An annotation of (C) indicates that the field is immutable.
*
* In contrast, the synchronization of accesses to the page's
* dirty field is machine dependent (M). In the
* machine-independent layer, the lock on the object that the
* page belongs to must be held in order to operate on the field.
* However, the pmap layer is permitted to set all bits within
* the field without holding that lock. If the underlying
* architecture does not support atomic read-modify-write
* operations on the field's type, then the machine-independent
* layer uses a 32-bit atomic on the aligned 32-bit word that
* contains the dirty field. In the machine-independent layer,
* the implementation of read-modify-write operations on the
* field is encapsulated in vm_page_clear_dirty_mask().
*
* The page structure contains two counters which prevent page reuse.
* Both counters are protected by the page lock (P). The hold
* counter counts transient references obtained via a pmap lookup, and
* is also used to prevent page reclamation in situations where it is
* undesirable to block other accesses to the page. The wire counter
* is used to implement mlock(2) and is non-zero for pages containing
* kernel memory. Pages that are wired or held will not be reclaimed
* or laundered by the page daemon, but are treated differently during
* a page queue scan: held pages remain at their position in the queue,
* while wired pages are removed from the queue and must later be
* re-enqueued appropriately by the unwiring thread. It is legal to
* call vm_page_free() on a held page; doing so causes it to be removed
* from its object and page queue, and the page is released to the
* allocator once the last hold reference is dropped. In contrast,
* wired pages may not be freed.
*
* In some pmap implementations, the wire count of a page table page is
* used to track the number of populated entries.
*
* The busy lock is an embedded reader-writer lock which protects the
* page's contents and identity (i.e., its <object, pindex> tuple) and
* interlocks with the object lock (O). In particular, a page may be
* busied or unbusied only with the object write lock held. To avoid
* bloating the page structure, the busy lock lacks some of the
* features available to the kernel's general-purpose synchronization
* primitives. As a result, busy lock ordering rules are not verified,
* lock recursion is not detected, and an attempt to xbusy a busy page
* or sbusy an xbusy page results will trigger a panic rather than
* causing the thread to block. vm_page_sleep_if_busy() can be used to
* sleep until the page's busy state changes, after which the caller
* must re-lookup the page and re-evaluate its state.
*
* The queue field is the index of the page queue containing the
* page, or PQ_NONE if the page is not enqueued. The queue lock of a
* page is the page queue lock corresponding to the page queue index,
* or the page lock (P) for the page if it is not enqueued. To modify
* the queue field, the queue lock for the old value of the field must
* be held. It is invalid for a page's queue field to transition
* between two distinct page queue indices. That is, when updating
* the queue field, either the new value or the old value must be
* PQ_NONE.
*
* To avoid contention on page queue locks, page queue operations
* (enqueue, dequeue, requeue) are batched using per-CPU queues.
* A deferred operation is requested by inserting an entry into a
* batch queue; the entry is simply a pointer to the page, and the
* request type is encoded in the page's aflags field using the values
* in PGA_QUEUE_STATE_MASK. The type-stability of struct vm_pages is
* crucial to this scheme since the processing of entries in a given
* batch queue may be deferred indefinitely. In particular, a page
* may be freed before its pending batch queue entries have been
* processed. The page lock (P) must be held to schedule a batched
* queue operation, and the page queue lock must be held in order to
* process batch queue entries for the page queue.
*/
#if PAGE_SIZE == 4096
#define VM_PAGE_BITS_ALL 0xffu
typedef uint8_t vm_page_bits_t;
#elif PAGE_SIZE == 8192
#define VM_PAGE_BITS_ALL 0xffffu
typedef uint16_t vm_page_bits_t;
#elif PAGE_SIZE == 16384
#define VM_PAGE_BITS_ALL 0xffffffffu
typedef uint32_t vm_page_bits_t;
#elif PAGE_SIZE == 32768
#define VM_PAGE_BITS_ALL 0xfffffffffffffffflu
typedef uint64_t vm_page_bits_t;
#endif
struct vm_page {
union {
TAILQ_ENTRY(vm_page) q; /* page queue or free list (Q) */
struct {
SLIST_ENTRY(vm_page) ss; /* private slists */
void *pv;
} s;
struct {
u_long p;
u_long v;
} memguard;
} plinks;
TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */
vm_object_t object; /* which object am I in (O,P) */
vm_pindex_t pindex; /* offset into object (O,P) */
vm_paddr_t phys_addr; /* physical address of page (C) */
struct md_page md; /* machine dependent stuff */
u_int wire_count; /* wired down maps refs (P) */
volatile u_int busy_lock; /* busy owners lock */
uint16_t hold_count; /* page hold count (P) */
uint16_t flags; /* page PG_* flags (P) */
uint8_t aflags; /* access is atomic */
uint8_t oflags; /* page VPO_* flags (O) */
uint8_t queue; /* page queue index (Q) */
int8_t psind; /* pagesizes[] index (O) */
int8_t segind; /* vm_phys segment index (C) */
uint8_t order; /* index of the buddy queue (F) */
uint8_t pool; /* vm_phys freepool index (F) */
u_char act_count; /* page usage count (P) */
/* NOTE that these must support one bit per DEV_BSIZE in a page */
/* so, on normal X86 kernels, they must be at least 8 bits wide */
vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */
vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */
};
/*
* Page flags stored in oflags:
*
* Access to these page flags is synchronized by the lock on the object
* containing the page (O).
*
* Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG)
* indicates that the page is not under PV management but
* otherwise should be treated as a normal page. Pages not
* under PV management cannot be paged out via the
* object/vm_page_t because there is no knowledge of their pte
* mappings, and such pages are also not on any PQ queue.
*
*/
#define VPO_KMEM_EXEC 0x01 /* kmem mapping allows execution */
#define VPO_SWAPSLEEP 0x02 /* waiting for swap to finish */
#define VPO_UNMANAGED 0x04 /* no PV management for page */
#define VPO_SWAPINPROG 0x08 /* swap I/O in progress on page */
#define VPO_NOSYNC 0x10 /* do not collect for syncer */
/*
* Busy page implementation details.
* The algorithm is taken mostly by rwlock(9) and sx(9) locks implementation,
* even if the support for owner identity is removed because of size
* constraints. Checks on lock recursion are then not possible, while the
* lock assertions effectiveness is someway reduced.
*/
#define VPB_BIT_SHARED 0x01
#define VPB_BIT_EXCLUSIVE 0x02
#define VPB_BIT_WAITERS 0x04
#define VPB_BIT_FLAGMASK \
(VPB_BIT_SHARED | VPB_BIT_EXCLUSIVE | VPB_BIT_WAITERS)
#define VPB_SHARERS_SHIFT 3
#define VPB_SHARERS(x) \
(((x) & ~VPB_BIT_FLAGMASK) >> VPB_SHARERS_SHIFT)
#define VPB_SHARERS_WORD(x) ((x) << VPB_SHARERS_SHIFT | VPB_BIT_SHARED)
#define VPB_ONE_SHARER (1 << VPB_SHARERS_SHIFT)
#define VPB_SINGLE_EXCLUSIVER VPB_BIT_EXCLUSIVE
#define VPB_UNBUSIED VPB_SHARERS_WORD(0)
#define PQ_NONE 255
#define PQ_INACTIVE 0
#define PQ_ACTIVE 1
#define PQ_LAUNDRY 2
#define PQ_UNSWAPPABLE 3
#define PQ_COUNT 4
#ifndef VM_PAGE_HAVE_PGLIST
TAILQ_HEAD(pglist, vm_page);
#define VM_PAGE_HAVE_PGLIST
#endif
SLIST_HEAD(spglist, vm_page);
#ifdef _KERNEL
extern vm_page_t bogus_page;
#endif /* _KERNEL */
extern struct mtx_padalign pa_lock[];
#if defined(__arm__)
#define PDRSHIFT PDR_SHIFT
#elif !defined(PDRSHIFT)
#define PDRSHIFT 21
#endif
#define pa_index(pa) ((pa) >> PDRSHIFT)
#define PA_LOCKPTR(pa) ((struct mtx *)(&pa_lock[pa_index(pa) % PA_LOCK_COUNT]))
#define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa)))
#define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa))
#define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa))
#define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa))
#define PA_UNLOCK_COND(pa) \
do { \
if ((pa) != 0) { \
PA_UNLOCK((pa)); \
(pa) = 0; \
} \
} while (0)
#define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a))
#if defined(KLD_MODULE) && !defined(KLD_TIED)
#define vm_page_lock(m) vm_page_lock_KBI((m), LOCK_FILE, LOCK_LINE)
#define vm_page_unlock(m) vm_page_unlock_KBI((m), LOCK_FILE, LOCK_LINE)
#define vm_page_trylock(m) vm_page_trylock_KBI((m), LOCK_FILE, LOCK_LINE)
#else /* !KLD_MODULE */
#define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m))))
#define vm_page_lock(m) mtx_lock(vm_page_lockptr((m)))
#define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m)))
#define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m)))
#endif
#if defined(INVARIANTS)
#define vm_page_assert_locked(m) \
vm_page_assert_locked_KBI((m), __FILE__, __LINE__)
#define vm_page_lock_assert(m, a) \
vm_page_lock_assert_KBI((m), (a), __FILE__, __LINE__)
#else
#define vm_page_assert_locked(m)
#define vm_page_lock_assert(m, a)
#endif
/*
* The vm_page's aflags are updated using atomic operations. To set or clear
* these flags, the functions vm_page_aflag_set() and vm_page_aflag_clear()
* must be used. Neither these flags nor these functions are part of the KBI.
*
* PGA_REFERENCED may be cleared only if the page is locked. It is set by
* both the MI and MD VM layers. However, kernel loadable modules should not
* directly set this flag. They should call vm_page_reference() instead.
*
* PGA_WRITEABLE is set exclusively on managed pages by pmap_enter().
* When it does so, the object must be locked, or the page must be
* exclusive busied. The MI VM layer must never access this flag
* directly. Instead, it should call pmap_page_is_write_mapped().
*
* PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has
* at least one executable mapping. It is not consumed by the MI VM layer.
*
* PGA_ENQUEUED is set and cleared when a page is inserted into or removed
* from a page queue, respectively. It determines whether the plinks.q field
* of the page is valid. To set or clear this flag, the queue lock for the
* page must be held: the page queue lock corresponding to the page's "queue"
* field if its value is not PQ_NONE, and the page lock otherwise.
*
* PGA_DEQUEUE is set when the page is scheduled to be dequeued from a page
* queue, and cleared when the dequeue request is processed. A page may
* have PGA_DEQUEUE set and PGA_ENQUEUED cleared, for instance if a dequeue
* is requested after the page is scheduled to be enqueued but before it is
* actually inserted into the page queue. The page lock must be held to set
* this flag, and the queue lock for the page must be held to clear it.
*
* PGA_REQUEUE is set when the page is scheduled to be enqueued or requeued
* in its page queue. The page lock must be held to set this flag, and the
* queue lock for the page must be held to clear it.
*
* PGA_REQUEUE_HEAD is a special flag for enqueuing pages near the head of
* the inactive queue, thus bypassing LRU. The page lock must be held to
* set this flag, and the queue lock for the page must be held to clear it.
*/
#define PGA_WRITEABLE 0x01 /* page may be mapped writeable */
#define PGA_REFERENCED 0x02 /* page has been referenced */
#define PGA_EXECUTABLE 0x04 /* page may be mapped executable */
#define PGA_ENQUEUED 0x08 /* page is enqueued in a page queue */
#define PGA_DEQUEUE 0x10 /* page is due to be dequeued */
#define PGA_REQUEUE 0x20 /* page is due to be requeued */
#define PGA_REQUEUE_HEAD 0x40 /* page requeue should bypass LRU */
#define PGA_QUEUE_STATE_MASK (PGA_ENQUEUED | PGA_DEQUEUE | PGA_REQUEUE | \
PGA_REQUEUE_HEAD)
/*
* Page flags. If changed at any other time than page allocation or
* freeing, the modification must be protected by the vm_page lock.
*/
#define PG_FICTITIOUS 0x0004 /* physical page doesn't exist */
#define PG_ZERO 0x0008 /* page is zeroed */
#define PG_MARKER 0x0010 /* special queue marker page */
#define PG_NODUMP 0x0080 /* don't include this page in a dump */
#define PG_UNHOLDFREE 0x0100 /* delayed free of a held page */
/*
* Misc constants.
*/
#define ACT_DECLINE 1
#define ACT_ADVANCE 3
#define ACT_INIT 5
#define ACT_MAX 64
#ifdef _KERNEL
#include <sys/systm.h>
#include <machine/atomic.h>
/*
* Each pageable resident page falls into one of five lists:
*
* free
* Available for allocation now.
*
* inactive
* Low activity, candidates for reclamation.
* This list is approximately LRU ordered.
*
* laundry
* This is the list of pages that should be
* paged out next.
*
* unswappable
* Dirty anonymous pages that cannot be paged
* out because no swap device is configured.
*
* active
* Pages that are "active", i.e., they have been
* recently referenced.
*
*/
extern vm_page_t vm_page_array; /* First resident page in table */
extern long vm_page_array_size; /* number of vm_page_t's */
extern long first_page; /* first physical page number */
#define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr)
/*
* PHYS_TO_VM_PAGE() returns the vm_page_t object that represents a memory
* page to which the given physical address belongs. The correct vm_page_t
* object is returned for addresses that are not page-aligned.
*/
vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa);
/*
* Page allocation parameters for vm_page for the functions
* vm_page_alloc(), vm_page_grab(), vm_page_alloc_contig() and
* vm_page_alloc_freelist(). Some functions support only a subset
* of the flags, and ignore others, see the flags legend.
*
* The meaning of VM_ALLOC_ZERO differs slightly between the vm_page_alloc*()
* and the vm_page_grab*() functions. See these functions for details.
*
* Bits 0 - 1 define class.
* Bits 2 - 15 dedicated for flags.
* Legend:
* (a) - vm_page_alloc() supports the flag.
* (c) - vm_page_alloc_contig() supports the flag.
* (f) - vm_page_alloc_freelist() supports the flag.
* (g) - vm_page_grab() supports the flag.
* (p) - vm_page_grab_pages() supports the flag.
* Bits above 15 define the count of additional pages that the caller
* intends to allocate.
*/
#define VM_ALLOC_NORMAL 0
#define VM_ALLOC_INTERRUPT 1
#define VM_ALLOC_SYSTEM 2
#define VM_ALLOC_CLASS_MASK 3
#define VM_ALLOC_WAITOK 0x0008 /* (acf) Sleep and retry */
#define VM_ALLOC_WAITFAIL 0x0010 /* (acf) Sleep and return error */
#define VM_ALLOC_WIRED 0x0020 /* (acfgp) Allocate a wired page */
#define VM_ALLOC_ZERO 0x0040 /* (acfgp) Allocate a prezeroed page */
#define VM_ALLOC_NOOBJ 0x0100 /* (acg) No associated object */
#define VM_ALLOC_NOBUSY 0x0200 /* (acgp) Do not excl busy the page */
#define VM_ALLOC_IGN_SBUSY 0x1000 /* (gp) Ignore shared busy flag */
#define VM_ALLOC_NODUMP 0x2000 /* (ag) don't include in dump */
#define VM_ALLOC_SBUSY 0x4000 /* (acgp) Shared busy the page */
#define VM_ALLOC_NOWAIT 0x8000 /* (acfgp) Do not sleep */
#define VM_ALLOC_COUNT_SHIFT 16
#define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT)
#ifdef M_NOWAIT
static inline int
malloc2vm_flags(int malloc_flags)
{
int pflags;
KASSERT((malloc_flags & M_USE_RESERVE) == 0 ||
(malloc_flags & M_NOWAIT) != 0,
("M_USE_RESERVE requires M_NOWAIT"));
pflags = (malloc_flags & M_USE_RESERVE) != 0 ? VM_ALLOC_INTERRUPT :
VM_ALLOC_SYSTEM;
if ((malloc_flags & M_ZERO) != 0)
pflags |= VM_ALLOC_ZERO;
if ((malloc_flags & M_NODUMP) != 0)
pflags |= VM_ALLOC_NODUMP;
if ((malloc_flags & M_NOWAIT))
pflags |= VM_ALLOC_NOWAIT;
if ((malloc_flags & M_WAITOK))
pflags |= VM_ALLOC_WAITOK;
return (pflags);
}
#endif
/*
* Predicates supported by vm_page_ps_test():
*
* PS_ALL_DIRTY is true only if the entire (super)page is dirty.
* However, it can be spuriously false when the (super)page has become
* dirty in the pmap but that information has not been propagated to the
* machine-independent layer.
*/
#define PS_ALL_DIRTY 0x1
#define PS_ALL_VALID 0x2
#define PS_NONE_BUSY 0x4
void vm_page_busy_downgrade(vm_page_t m);
void vm_page_busy_sleep(vm_page_t m, const char *msg, bool nonshared);
void vm_page_flash(vm_page_t m);
void vm_page_hold(vm_page_t mem);
void vm_page_unhold(vm_page_t mem);
void vm_page_free(vm_page_t m);
void vm_page_free_zero(vm_page_t m);
void vm_page_activate (vm_page_t);
void vm_page_advise(vm_page_t m, int advice);
vm_page_t vm_page_alloc(vm_object_t, vm_pindex_t, int);
vm_page_t vm_page_alloc_domain(vm_object_t, vm_pindex_t, int, int);
vm_page_t vm_page_alloc_after(vm_object_t, vm_pindex_t, int, vm_page_t);
vm_page_t vm_page_alloc_domain_after(vm_object_t, vm_pindex_t, int, int,
vm_page_t);
vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req,
u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
vm_paddr_t boundary, vm_memattr_t memattr);
vm_page_t vm_page_alloc_contig_domain(vm_object_t object,
vm_pindex_t pindex, int domain, int req, u_long npages, vm_paddr_t low,
vm_paddr_t high, u_long alignment, vm_paddr_t boundary,
vm_memattr_t memattr);
vm_page_t vm_page_alloc_freelist(int, int);
vm_page_t vm_page_alloc_freelist_domain(int, int, int);
bool vm_page_blacklist_add(vm_paddr_t pa, bool verbose);
void vm_page_change_lock(vm_page_t m, struct mtx **mtx);
vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int);
int vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags,
vm_page_t *ma, int count);
void vm_page_deactivate(vm_page_t);
void vm_page_deactivate_noreuse(vm_page_t);
void vm_page_dequeue(vm_page_t m);
void vm_page_dequeue_deferred(vm_page_t m);
void vm_page_drain_pqbatch(void);
vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t);
bool vm_page_free_prep(vm_page_t m);
vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr);
void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr);
int vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t);
void vm_page_launder(vm_page_t m);
vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t);
vm_page_t vm_page_next(vm_page_t m);
int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *);
struct vm_pagequeue *vm_page_pagequeue(vm_page_t m);
vm_page_t vm_page_prev(vm_page_t m);
bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m);
void vm_page_putfake(vm_page_t m);
void vm_page_readahead_finish(vm_page_t m);
bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low,
vm_paddr_t high, u_long alignment, vm_paddr_t boundary);
bool vm_page_reclaim_contig_domain(int domain, int req, u_long npages,
vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary);
void vm_page_reference(vm_page_t m);
void vm_page_remove (vm_page_t);
int vm_page_rename (vm_page_t, vm_object_t, vm_pindex_t);
vm_page_t vm_page_replace(vm_page_t mnew, vm_object_t object,
vm_pindex_t pindex);
void vm_page_requeue(vm_page_t m);
int vm_page_sbusied(vm_page_t m);
vm_page_t vm_page_scan_contig(u_long npages, vm_page_t m_start,
vm_page_t m_end, u_long alignment, vm_paddr_t boundary, int options);
void vm_page_set_valid_range(vm_page_t m, int base, int size);
int vm_page_sleep_if_busy(vm_page_t m, const char *msg);
vm_offset_t vm_page_startup(vm_offset_t vaddr);
void vm_page_sunbusy(vm_page_t m);
bool vm_page_try_to_free(vm_page_t m);
int vm_page_trysbusy(vm_page_t m);
void vm_page_unhold_pages(vm_page_t *ma, int count);
void vm_page_unswappable(vm_page_t m);
bool vm_page_unwire(vm_page_t m, uint8_t queue);
bool vm_page_unwire_noq(vm_page_t m);
void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr);
void vm_page_wire (vm_page_t);
void vm_page_xunbusy_hard(vm_page_t m);
void vm_page_xunbusy_maybelocked(vm_page_t m);
void vm_page_set_validclean (vm_page_t, int, int);
void vm_page_clear_dirty (vm_page_t, int, int);
void vm_page_set_invalid (vm_page_t, int, int);
int vm_page_is_valid (vm_page_t, int, int);
void vm_page_test_dirty (vm_page_t);
vm_page_bits_t vm_page_bits(int base, int size);
void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid);
void vm_page_free_toq(vm_page_t m);
void vm_page_free_pages_toq(struct spglist *free, bool update_wire_count);
void vm_page_dirty_KBI(vm_page_t m);
void vm_page_lock_KBI(vm_page_t m, const char *file, int line);
void vm_page_unlock_KBI(vm_page_t m, const char *file, int line);
int vm_page_trylock_KBI(vm_page_t m, const char *file, int line);
#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
void vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line);
void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line);
#endif
#define vm_page_assert_sbusied(m) \
KASSERT(vm_page_sbusied(m), \
("vm_page_assert_sbusied: page %p not shared busy @ %s:%d", \
(m), __FILE__, __LINE__))
#define vm_page_assert_unbusied(m) \
KASSERT(!vm_page_busied(m), \
("vm_page_assert_unbusied: page %p busy @ %s:%d", \
(m), __FILE__, __LINE__))
#define vm_page_assert_xbusied(m) \
KASSERT(vm_page_xbusied(m), \
("vm_page_assert_xbusied: page %p not exclusive busy @ %s:%d", \
(m), __FILE__, __LINE__))
#define vm_page_busied(m) \
((m)->busy_lock != VPB_UNBUSIED)
#define vm_page_sbusy(m) do { \
if (!vm_page_trysbusy(m)) \
panic("%s: page %p failed shared busying", __func__, \
(m)); \
} while (0)
#define vm_page_tryxbusy(m) \
(atomic_cmpset_acq_int(&(m)->busy_lock, VPB_UNBUSIED, \
VPB_SINGLE_EXCLUSIVER))
#define vm_page_xbusied(m) \
(((m)->busy_lock & VPB_SINGLE_EXCLUSIVER) != 0)
#define vm_page_xbusy(m) do { \
if (!vm_page_tryxbusy(m)) \
panic("%s: page %p failed exclusive busying", __func__, \
(m)); \
} while (0)
/* Note: page m's lock must not be owned by the caller. */
#define vm_page_xunbusy(m) do { \
if (!atomic_cmpset_rel_int(&(m)->busy_lock, \
VPB_SINGLE_EXCLUSIVER, VPB_UNBUSIED)) \
vm_page_xunbusy_hard(m); \
} while (0)
#ifdef INVARIANTS
void vm_page_object_lock_assert(vm_page_t m);
#define VM_PAGE_OBJECT_LOCK_ASSERT(m) vm_page_object_lock_assert(m)
void vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits);
#define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) \
vm_page_assert_pga_writeable(m, bits)
#else
#define VM_PAGE_OBJECT_LOCK_ASSERT(m) (void)0
#define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) (void)0
#endif
/*
* We want to use atomic updates for the aflags field, which is 8 bits wide.
* However, not all architectures support atomic operations on 8-bit
* destinations. In order that we can easily use a 32-bit operation, we
* require that the aflags field be 32-bit aligned.
*/
CTASSERT(offsetof(struct vm_page, aflags) % sizeof(uint32_t) == 0);
/*
* Clear the given bits in the specified page.
*/
static inline void
vm_page_aflag_clear(vm_page_t m, uint8_t bits)
{
uint32_t *addr, val;
/*
* The PGA_REFERENCED flag can only be cleared if the page is locked.
*/
if ((bits & PGA_REFERENCED) != 0)
vm_page_assert_locked(m);
/*
* Access the whole 32-bit word containing the aflags field with an
* atomic update. Parallel non-atomic updates to the other fields
* within this word are handled properly by the atomic update.
*/
addr = (void *)&m->aflags;
KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0,
("vm_page_aflag_clear: aflags is misaligned"));
val = bits;
#if BYTE_ORDER == BIG_ENDIAN
val <<= 24;
#endif
atomic_clear_32(addr, val);
}
/*
* Set the given bits in the specified page.
*/
static inline void
vm_page_aflag_set(vm_page_t m, uint8_t bits)
{
uint32_t *addr, val;
VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits);
/*
* Access the whole 32-bit word containing the aflags field with an
* atomic update. Parallel non-atomic updates to the other fields
* within this word are handled properly by the atomic update.
*/
addr = (void *)&m->aflags;
KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0,
("vm_page_aflag_set: aflags is misaligned"));
val = bits;
#if BYTE_ORDER == BIG_ENDIAN
val <<= 24;
#endif
atomic_set_32(addr, val);
}
/*
* vm_page_dirty:
*
* Set all bits in the page's dirty field.
*
* The object containing the specified page must be locked if the
* call is made from the machine-independent layer.
*
* See vm_page_clear_dirty_mask().
*/
static __inline void
vm_page_dirty(vm_page_t m)
{
/* Use vm_page_dirty_KBI() under INVARIANTS to save memory. */
#if (defined(KLD_MODULE) && !defined(KLD_TIED)) || defined(INVARIANTS)
vm_page_dirty_KBI(m);
#else
m->dirty = VM_PAGE_BITS_ALL;
#endif
}
/*
* vm_page_undirty:
*
* Set page to not be dirty. Note: does not clear pmap modify bits
*/
static __inline void
vm_page_undirty(vm_page_t m)
{
VM_PAGE_OBJECT_LOCK_ASSERT(m);
m->dirty = 0;
}
static inline void
vm_page_replace_checked(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex,
vm_page_t mold)
{
vm_page_t mret;
mret = vm_page_replace(mnew, object, pindex);
KASSERT(mret == mold,
("invalid page replacement, mold=%p, mret=%p", mold, mret));
/* Unused if !INVARIANTS. */
(void)mold;
(void)mret;
}
/*
* vm_page_queue:
*
* Return the index of the queue containing m. This index is guaranteed
* not to change while the page lock is held.
*/
static inline uint8_t
vm_page_queue(vm_page_t m)
{
vm_page_assert_locked(m);
if ((m->aflags & PGA_DEQUEUE) != 0)
return (PQ_NONE);
atomic_thread_fence_acq();
return (m->queue);
}
static inline bool
vm_page_active(vm_page_t m)
{
return (vm_page_queue(m) == PQ_ACTIVE);
}
static inline bool
vm_page_inactive(vm_page_t m)
{
return (vm_page_queue(m) == PQ_INACTIVE);
}
static inline bool
vm_page_in_laundry(vm_page_t m)
{
uint8_t queue;
queue = vm_page_queue(m);
return (queue == PQ_LAUNDRY || queue == PQ_UNSWAPPABLE);
}
/*
* vm_page_held:
*
* Return true if a reference prevents the page from being reclaimable.
*/
static inline bool
vm_page_held(vm_page_t m)
{
return (m->hold_count > 0 || m->wire_count > 0);
}
#endif /* _KERNEL */
#endif /* !_VM_PAGE_ */
