NetBSD/sys/vm/vm_page.h
1999-12-30 16:09:47 +00:00

416 lines
13 KiB
C++

/* $NetBSD: vm_page.h,v 1.34 1999/12/30 16:09:47 eeh Exp $ */
/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* @(#)vm_page.h 8.3 (Berkeley) 1/9/95
*
*
* 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.
*/
/*
* Resident memory system definitions.
*/
#ifndef _VM_PAGE_
#define _VM_PAGE_
/*
* 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 lists:
*
* A hash table bucket 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.
*
* Fields in this structure are locked either by the lock on the
* object that the page belongs to (O) or by the lock on the page
* queues (P) [or both].
*/
/*
* locking note: the mach version of this data structure had bit
* fields for the flags, and the bit fields were divided into two
* items (depending on who locked what). some time, in BSD, the bit
* fields were dumped and all the flags were lumped into one short.
* that is fine for a single threaded uniprocessor OS, but bad if you
* want to actual make use of locking (simple_lock's). so, we've
* seperated things back out again.
*
* note the page structure has no lock of its own.
*/
#include <uvm/uvm_extern.h>
#include <vm/pglist.h>
struct vm_page {
TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO
* queue or free list (P) */
TAILQ_ENTRY(vm_page) hashq; /* hash table links (O)*/
TAILQ_ENTRY(vm_page) listq; /* pages in same object (O)*/
vaddr_t offset; /* offset into object (O,P) */
struct uvm_object *uobject; /* object (O,P) */
struct vm_anon *uanon; /* anon (O,P) */
u_short flags; /* object flags [O] */
u_short version; /* version count [O] */
u_short wire_count; /* wired down map refs [P] */
u_short pqflags; /* page queue flags [P] */
u_int loan_count; /* number of active loans
* to read: [O or P]
* to modify: [O _and_ P] */
paddr_t phys_addr; /* physical address of page */
#if defined(UVM_PAGE_TRKOWN)
/* debugging fields to track page ownership */
pid_t owner; /* proc that set PG_BUSY */
char *owner_tag; /* why it was set busy */
#endif
};
/*
* These are the flags defined for vm_page.
*
* Note: PG_FILLED and PG_DIRTY are added for the filesystems.
*/
/*
* locking rules:
* PG_ ==> locked by object lock
* PQ_ ==> lock by page queue lock
* PQ_FREE is locked by free queue lock and is mutex with all other PQs
*
* possible deadwood: PG_FAULTING, PQ_LAUNDRY
*/
#define PG_CLEAN 0x0008 /* page has not been modified */
#define PG_BUSY 0x0010 /* page is in transit */
#define PG_WANTED 0x0020 /* someone is waiting for page */
#define PG_TABLED 0x0040 /* page is in VP table */
#define PG_FAKE 0x0200 /* page is placeholder for pagein */
#define PG_FILLED 0x0400 /* client flag to set when filled */
#define PG_DIRTY 0x0800 /* client flag to set when dirty */
#define PG_RELEASED 0x1000 /* page released while paging */
#define PG_FAULTING 0x2000 /* page is being faulted in */
#define PG_CLEANCHK 0x4000 /* clean bit has been checked */
#define PQ_FREE 0x0001 /* page is on free list */
#define PQ_INACTIVE 0x0002 /* page is in inactive list */
#define PQ_ACTIVE 0x0004 /* page is in active list */
#define PQ_LAUNDRY 0x0008 /* page is being cleaned now */
#define PQ_ANON 0x0010 /* page is part of an anon, rather
than an uvm_object */
#define PQ_AOBJ 0x0020 /* page is part of an anonymous
uvm_object */
#define PQ_SWAPBACKED (PQ_ANON|PQ_AOBJ)
/*
* physical memory layout structure
*
* MD vmparam.h must #define:
* VM_PHYSEG_MAX = max number of physical memory segments we support
* (if this is "1" then we revert to a "contig" case)
* VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1)
* - VM_PSTRAT_RANDOM: linear search (random order)
* - VM_PSTRAT_BSEARCH: binary search (sorted by address)
* - VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
* - others?
* XXXCDC: eventually we should remove contig and old non-contig cases
* and purge all left-over global variables...
*/
#define VM_PSTRAT_RANDOM 1
#define VM_PSTRAT_BSEARCH 2
#define VM_PSTRAT_BIGFIRST 3
/*
* vm_physmemseg: describes one segment of physical memory
*/
struct vm_physseg {
paddr_t start; /* PF# of first page in segment */
paddr_t end; /* (PF# of last page in segment) + 1 */
paddr_t avail_start; /* PF# of first free page in segment */
paddr_t avail_end; /* (PF# of last free page in segment) +1 */
int free_list; /* which free list they belong on */
struct vm_page *pgs; /* vm_page structures (from start) */
struct vm_page *lastpg; /* vm_page structure for end */
struct pmap_physseg pmseg; /* pmap specific (MD) data */
};
#if defined(_KERNEL)
/*
* Each pageable resident page falls into one of three lists:
*
* free
* Available for allocation now.
* inactive
* Not referenced in any map, but still has an
* object/offset-page mapping, and may be dirty.
* This is the list of pages that should be
* paged out next.
* active
* A list of pages which have been placed in
* at least one physical map. This list is
* ordered, in LRU-like fashion.
*/
extern
struct pglist vm_page_queue_free; /* memory free queue */
extern
struct pglist vm_page_queue_active; /* active memory queue */
extern
struct pglist vm_page_queue_inactive; /* inactive memory queue */
/*
* physical memory config is stored in vm_physmem.
*/
extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
extern int vm_nphysseg;
/*
* prototypes
*/
static struct vm_page *PHYS_TO_VM_PAGE __P((paddr_t));
static int vm_physseg_find __P((paddr_t, int *));
/*
* macros and inlines
*/
#define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr)
/*
* when VM_PHYSSEG_MAX is 1, we can simplify these functions
*/
/*
* vm_physseg_find: find vm_physseg structure that belongs to a PA
*/
static __inline int
vm_physseg_find(pframe, offp)
paddr_t pframe;
int *offp;
{
#if VM_PHYSSEG_MAX == 1
/* 'contig' case */
if (pframe >= vm_physmem[0].start && pframe < vm_physmem[0].end) {
if (offp)
*offp = pframe - vm_physmem[0].start;
return(0);
}
return(-1);
#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
/* binary search for it */
int start, len, try;
/*
* if try is too large (thus target is less than than try) we reduce
* the length to trunc(len/2) [i.e. everything smaller than "try"]
*
* if the try is too small (thus target is greater than try) then
* we set the new start to be (try + 1). this means we need to
* reduce the length to (round(len/2) - 1).
*
* note "adjust" below which takes advantage of the fact that
* (round(len/2) - 1) == trunc((len - 1) / 2)
* for any value of len we may have
*/
for (start = 0, len = vm_nphysseg ; len != 0 ; len = len / 2) {
try = start + (len / 2); /* try in the middle */
/* start past our try? */
if (pframe >= vm_physmem[try].start) {
/* was try correct? */
if (pframe < vm_physmem[try].end) {
if (offp)
*offp = pframe - vm_physmem[try].start;
return(try); /* got it */
}
start = try + 1; /* next time, start here */
len--; /* "adjust" */
} else {
/*
* pframe before try, just reduce length of
* region, done in "for" loop
*/
}
}
return(-1);
#else
/* linear search for it */
int lcv;
for (lcv = 0; lcv < vm_nphysseg; lcv++) {
if (pframe >= vm_physmem[lcv].start &&
pframe < vm_physmem[lcv].end) {
if (offp)
*offp = pframe - vm_physmem[lcv].start;
return(lcv); /* got it */
}
}
return(-1);
#endif
}
/*
* IS_VM_PHYSADDR: only used my mips/pmax/pica trap/pmap.
*/
#define IS_VM_PHYSADDR(PA) (vm_physseg_find(atop(PA), NULL) != -1)
/*
* PHYS_TO_VM_PAGE: find vm_page for a PA. used by MI code to get vm_pages
* back from an I/O mapping (ugh!). used in some MD code as well.
*/
static __inline struct vm_page *
PHYS_TO_VM_PAGE(pa)
paddr_t pa;
{
paddr_t pf = atop(pa);
int off;
int psi;
psi = vm_physseg_find(pf, &off);
if (psi != -1)
return(&vm_physmem[psi].pgs[off]);
return(NULL);
}
#define VM_PAGE_IS_FREE(entry) ((entry)->pqflags & PQ_FREE)
extern
simple_lock_data_t vm_page_queue_lock; /* lock on active and inactive
page queues */
extern /* lock on free page queue */
simple_lock_data_t vm_page_queue_free_lock;
#define PAGE_ASSERT_WAIT(m, interruptible) { \
(m)->flags |= PG_WANTED; \
assert_wait((m), (interruptible)); \
}
#define PAGE_WAKEUP(m) { \
(m)->flags &= ~PG_BUSY; \
if ((m)->flags & PG_WANTED) { \
(m)->flags &= ~PG_WANTED; \
wakeup((m)); \
} \
}
#define vm_page_lock_queues() simple_lock(&vm_page_queue_lock)
#define vm_page_unlock_queues() simple_unlock(&vm_page_queue_lock)
#define vm_page_set_modified(m) { (m)->flags &= ~PG_CLEAN; }
#define VM_PAGE_INIT(mem, obj, offset) { \
(mem)->flags = PG_BUSY | PG_CLEAN | PG_FAKE; \
if (obj) \
vm_page_insert((mem), (obj), (offset)); \
else \
(mem)->object = NULL; \
(mem)->wire_count = 0; \
}
#if VM_PAGE_DEBUG
/*
* VM_PAGE_CHECK: debugging check of a vm_page structure
*/
static __inline void
VM_PAGE_CHECK(mem)
struct vm_page *mem;
{
int lcv;
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) {
if ((unsigned int) mem >= (unsigned int) vm_physmem[lcv].pgs &&
(unsigned int) mem <= (unsigned int) vm_physmem[lcv].lastpg)
break;
}
if (lcv == vm_nphysseg ||
(mem->flags & (PG_ACTIVE|PG_INACTIVE)) == (PG_ACTIVE|PG_INACTIVE))
panic("vm_page_check: not valid!");
return;
}
#else /* VM_PAGE_DEBUG */
#define VM_PAGE_CHECK(mem)
#endif /* VM_PAGE_DEBUG */
#endif /* _KERNEL */
#endif /* !_VM_PAGE_ */