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/* $OpenBSD: uvm_pglist.c,v 1.11 2001/11/28 19:28:15 art Exp $ */
/* $NetBSD: uvm_pglist.c,v 1.17 2001/06/27 21:18:34 thorpej Exp $ */
/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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 NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* uvm_pglist.c: pglist functions
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <uvm/uvm.h>
#ifdef VM_PAGE_ALLOC_MEMORY_STATS
#define STAT_INCR(v) (v)++
#define STAT_DECR(v) do { \
if ((v) == 0) \
printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \
else \
(v)--; \
} while (0)
u_long uvm_pglistalloc_npages;
#else
#define STAT_INCR(v)
#define STAT_DECR(v)
#endif
/*
* uvm_pglistalloc: allocate a list of pages
*
* => allocated pages are placed at the tail of rlist. rlist is
* assumed to be properly initialized by caller.
* => returns 0 on success or errno on failure
* => XXX: implementation allocates only a single segment, also
* might be able to better advantage of vm_physeg[].
* => doesn't take into account clean non-busy pages on inactive list
* that could be used(?)
* => params:
* size the size of the allocation, rounded to page size.
* low the low address of the allowed allocation range.
* high the high address of the allowed allocation range.
* alignment memory must be aligned to this power-of-two boundary.
* boundary no segment in the allocation may cross this
* power-of-two boundary (relative to zero).
*/
int
uvm_pglistalloc(size, low, high, alignment, boundary, rlist, nsegs, waitok)
psize_t size;
paddr_t low, high, alignment, boundary;
struct pglist *rlist;
int nsegs, waitok;
{
paddr_t try, idxpa, lastidxpa;
int psi;
struct vm_page *pgs;
int s, tryidx, idx, pgflidx, end, error, free_list, color;
struct vm_page *m;
u_long pagemask;
#ifdef DEBUG
struct vm_page *tp;
#endif
KASSERT((alignment & (alignment - 1)) == 0);
KASSERT((boundary & (boundary - 1)) == 0);
/*
* Our allocations are always page granularity, so our alignment
* must be, too.
*/
if (alignment < PAGE_SIZE)
alignment = PAGE_SIZE;
size = round_page(size);
try = roundup(low, alignment);
if (boundary != 0 && boundary < size)
return (EINVAL);
pagemask = ~(boundary - 1);
/* Default to "lose". */
error = ENOMEM;
/*
* Block all memory allocation and lock the free list.
*/
s = uvm_lock_fpageq();
/* Are there even any free pages? */
if (uvmexp.free <= (uvmexp.reserve_pagedaemon + uvmexp.reserve_kernel))
goto out;
for (;; try += alignment) {
if (try + size > high) {
/*
* We've run past the allowable range.
*/
goto out;
}
/*
* Make sure this is a managed physical page.
*/
if ((psi = vm_physseg_find(atop(try), &idx)) == -1)
continue; /* managed? */
if (vm_physseg_find(atop(try + size), NULL) != psi)
continue; /* end must be in this segment */
tryidx = idx;
end = idx + (size / PAGE_SIZE);
pgs = vm_physmem[psi].pgs;
/*
* Found a suitable starting page. See of the range is free.
*/
for (; idx < end; idx++) {
if (VM_PAGE_IS_FREE(&pgs[idx]) == 0) {
break;
}
idxpa = VM_PAGE_TO_PHYS(&pgs[idx]);
if (idx > tryidx) {
lastidxpa = VM_PAGE_TO_PHYS(&pgs[idx - 1]);
if ((lastidxpa + PAGE_SIZE) != idxpa) {
/*
* Region not contiguous.
*/
break;
}
if (boundary != 0 &&
((lastidxpa ^ idxpa) & pagemask) != 0) {
/*
* Region crosses boundary.
*/
break;
}
}
}
if (idx == end) {
break;
}
}
#if PGFL_NQUEUES != 2
#error uvm_pglistalloc needs to be updated
#endif
/*
* we have a chunk of memory that conforms to the requested constraints.
*/
idx = tryidx;
while (idx < end) {
m = &pgs[idx];
free_list = uvm_page_lookup_freelist(m);
color = VM_PGCOLOR_BUCKET(m);
pgflidx = (m->flags & PG_ZERO) ? PGFL_ZEROS : PGFL_UNKNOWN;
#ifdef DEBUG
for (tp = TAILQ_FIRST(&uvm.page_free[
free_list].pgfl_buckets[color].pgfl_queues[pgflidx]);
tp != NULL;
tp = TAILQ_NEXT(tp, pageq)) {
if (tp == m)
break;
}
if (tp == NULL)
panic("uvm_pglistalloc: page not on freelist");
#endif
TAILQ_REMOVE(&uvm.page_free[free_list].pgfl_buckets[
color].pgfl_queues[pgflidx], m, pageq);
uvmexp.free--;
if (m->flags & PG_ZERO)
uvmexp.zeropages--;
m->flags = PG_CLEAN;
m->pqflags = 0;
m->uobject = NULL;
m->uanon = NULL;
m->version++;
TAILQ_INSERT_TAIL(rlist, m, pageq);
idx++;
STAT_INCR(uvm_pglistalloc_npages);
}
error = 0;
out:
/*
* check to see if we need to generate some free pages waking
* the pagedaemon.
*/
UVM_KICK_PDAEMON();
uvm_unlock_fpageq(s);
return (error);
}
/*
* uvm_pglistfree: free a list of pages
*
* => pages should already be unmapped
*/
void
uvm_pglistfree(list)
struct pglist *list;
{
struct vm_page *m;
int s;
/*
* Block all memory allocation and lock the free list.
*/
s = uvm_lock_fpageq();
while ((m = TAILQ_FIRST(list)) != NULL) {
KASSERT((m->pqflags & (PQ_ACTIVE|PQ_INACTIVE)) == 0);
TAILQ_REMOVE(list, m, pageq);
m->pqflags = PQ_FREE;
TAILQ_INSERT_TAIL(&uvm.page_free[
uvm_page_lookup_freelist(m)].pgfl_buckets[
VM_PGCOLOR_BUCKET(m)].pgfl_queues[PGFL_UNKNOWN], m, pageq);
uvmexp.free++;
if (uvmexp.zeropages < UVM_PAGEZERO_TARGET)
uvm.page_idle_zero = vm_page_zero_enable;
STAT_DECR(uvm_pglistalloc_npages);
}
uvm_unlock_fpageq(s);
}
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