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59fa485c3e
(which was unfortunately turned off in the confguration I used for the last test build). Spotted by: jake Pointy hat to: tmm
578 lines
14 KiB
C
578 lines
14 KiB
C
/*
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* Copyright (c) 1997, 1998 John S. Dyson
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice immediately at the beginning of the file, without modification,
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* this list of conditions, and the following disclaimer.
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* 2. Absolutely no warranty of function or purpose is made by the author
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* John S. Dyson.
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*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/proc.h>
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#include <sys/mutex.h>
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#include <sys/queue.h>
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#include <sys/sysctl.h>
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#include <sys/vmmeter.h>
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#include <vm/vm.h>
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#include <vm/vm_object.h>
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#include <vm/vm_page.h>
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#include <vm/vm_param.h>
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#include <vm/vm_map.h>
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#include <vm/vm_kern.h>
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#include <vm/vm_extern.h>
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#include <vm/vm_zone.h>
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static MALLOC_DEFINE(M_ZONE, "ZONE", "Zone header");
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#define ZENTRY_FREE (void*)0x12342378
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#define ZONE_ROUNDING 32
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/*
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* This file comprises a very simple zone allocator. This is used
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* in lieu of the malloc allocator, where needed or more optimal.
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*
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* Note that the initial implementation of this had coloring, and
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* absolutely no improvement (actually perf degradation) occurred.
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*
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* Note also that the zones are type stable. The only restriction is
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* that the first two longwords of a data structure can be changed
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* between allocations. Any data that must be stable between allocations
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* must reside in areas after the first two longwords.
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*
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* zinitna, zinit, zbootinit are the initialization routines.
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* zalloc, zfree, are the allocation/free routines.
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*/
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/*
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* Subsystem lock. Never grab it while holding a zone lock.
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*/
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static struct mtx zone_mtx;
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/*
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* Singly-linked list of zones, for book-keeping purposes
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*/
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static SLIST_HEAD(vm_zone_list, vm_zone) zlist;
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/*
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* Statistics
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*/
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static int zone_kmem_pages; /* Number of interrupt-safe pages allocated */
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static int zone_kern_pages; /* Number of KVA pages allocated */
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static int zone_kmem_kvaspace; /* Number of non-intsafe pages allocated */
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/*
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* Subsystem initialization, called from vm_mem_init()
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*/
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void
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vm_zone_init(void)
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{
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mtx_init(&zone_mtx, "zone subsystem", MTX_DEF);
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SLIST_INIT(&zlist);
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}
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void
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vm_zone_init2(void)
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{
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/*
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* LATER: traverse zlist looking for partially initialized
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* LATER: zones and finish initializing them.
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*/
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}
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/*
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* Create a zone, but don't allocate the zone structure. If the
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* zone had been previously created by the zone boot code, initialize
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* various parts of the zone code.
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*
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* If waits are not allowed during allocation (e.g. during interrupt
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* code), a-priori allocate the kernel virtual space, and allocate
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* only pages when needed.
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*
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* Arguments:
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* z pointer to zone structure.
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* obj pointer to VM object (opt).
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* name name of zone.
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* size size of zone entries.
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* nentries number of zone entries allocated (only ZONE_INTERRUPT.)
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* flags ZONE_INTERRUPT -- items can be allocated at interrupt time.
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* zalloc number of pages allocated when memory is needed.
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*
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* Note that when using ZONE_INTERRUPT, the size of the zone is limited
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* by the nentries argument. The size of the memory allocatable is
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* unlimited if ZONE_INTERRUPT is not set.
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*
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*/
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int
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zinitna(vm_zone_t z, vm_object_t obj, char *name, int size,
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int nentries, int flags, int zalloc)
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{
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int totsize, oldzflags;
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GIANT_REQUIRED;
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oldzflags = z->zflags;
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if ((z->zflags & ZONE_BOOT) == 0) {
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z->zsize = (size + ZONE_ROUNDING - 1) & ~(ZONE_ROUNDING - 1);
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z->zfreecnt = 0;
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z->ztotal = 0;
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z->zmax = 0;
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z->zname = name;
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z->znalloc = 0;
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z->zitems = NULL;
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}
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z->zflags |= flags;
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/*
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* If we cannot wait, allocate KVA space up front, and we will fill
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* in pages as needed.
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*/
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if (z->zflags & ZONE_INTERRUPT) {
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totsize = round_page(z->zsize * nentries);
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atomic_add_int(&zone_kmem_kvaspace, totsize);
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z->zkva = kmem_alloc_pageable(kernel_map, totsize);
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if (z->zkva == 0)
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return 0;
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z->zpagemax = totsize / PAGE_SIZE;
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if (obj == NULL) {
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z->zobj = vm_object_allocate(OBJT_DEFAULT, z->zpagemax);
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} else {
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z->zobj = obj;
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_vm_object_allocate(OBJT_DEFAULT, z->zpagemax, obj);
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}
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z->zallocflag = VM_ALLOC_INTERRUPT;
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z->zmax += nentries;
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} else {
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z->zallocflag = VM_ALLOC_SYSTEM;
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z->zmax = 0;
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}
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if (z->zsize > PAGE_SIZE)
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z->zfreemin = 1;
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else
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z->zfreemin = PAGE_SIZE / z->zsize;
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z->zpagecount = 0;
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if (zalloc)
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z->zalloc = zalloc;
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else
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z->zalloc = 1;
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/* our zone is good and ready, add it to the list */
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if ((z->zflags & ZONE_BOOT) == 0) {
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mtx_init(&(z)->zmtx, "zone", MTX_DEF);
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mtx_lock(&zone_mtx);
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SLIST_INSERT_HEAD(&zlist, z, zent);
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mtx_unlock(&zone_mtx);
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}
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return 1;
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}
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/*
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* Subroutine same as zinitna, except zone data structure is allocated
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* automatically by malloc. This routine should normally be used, except
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* in certain tricky startup conditions in the VM system -- then
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* zbootinit and zinitna can be used. Zinit is the standard zone
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* initialization call.
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*/
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vm_zone_t
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zinit(char *name, int size, int nentries, int flags, int zalloc)
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{
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vm_zone_t z;
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z = (vm_zone_t) malloc(sizeof (struct vm_zone), M_ZONE, M_NOWAIT | M_ZERO);
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if (z == NULL)
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return NULL;
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if (zinitna(z, NULL, name, size, nentries, flags, zalloc) == 0) {
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free(z, M_ZONE);
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return NULL;
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}
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return z;
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}
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/*
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* Initialize a zone before the system is fully up.
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*
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* We can't rely on being able to allocate items dynamically, so we
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* kickstart the zone with a number of static items provided by the
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* caller.
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*
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* This routine should only be called before full VM startup.
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*/
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void
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zbootinit(vm_zone_t z, char *name, int size, void *item, int nitems)
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{
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int i;
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z->zname = name;
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z->zsize = size;
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z->zpagemax = 0;
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z->zobj = NULL;
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z->zflags = ZONE_BOOT;
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z->zfreemin = 0;
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z->zallocflag = 0;
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z->zpagecount = 0;
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z->zalloc = 0;
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z->znalloc = 0;
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mtx_init(&(z)->zmtx, "zone", MTX_DEF);
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bzero(item, nitems * z->zsize);
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z->zitems = NULL;
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for (i = 0; i < nitems; i++) {
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((void **) item)[0] = z->zitems;
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#ifdef INVARIANTS
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((void **) item)[1] = ZENTRY_FREE;
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#endif
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z->zitems = item;
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(char *) item += z->zsize;
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}
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z->zfreecnt = nitems;
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z->zmax = nitems;
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z->ztotal = nitems;
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mtx_lock(&zone_mtx);
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SLIST_INSERT_HEAD(&zlist, z, zent);
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mtx_unlock(&zone_mtx);
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}
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/*
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* Destroy a zone, freeing the allocated memory.
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* This does not do any locking for the zone; make sure it is not used
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* any more before calling. All zalloc()'ated memory in the zone must have
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* been zfree()'d.
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* zdestroy() may not be used with zbootinit()'ed zones.
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*/
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void
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zdestroy(vm_zone_t z)
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{
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int i, nitems, nbytes;
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void *item, *min, **itp;
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vm_map_t map;
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vm_map_entry_t entry;
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vm_object_t obj;
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vm_pindex_t pindex;
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vm_prot_t prot;
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boolean_t wired;
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GIANT_REQUIRED;
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KASSERT(z != NULL, ("invalid zone"));
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/*
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* This is needed, or the algorithm used for non-interrupt zones will
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* blow up badly.
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*/
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KASSERT(z->ztotal == z->zfreecnt,
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("zdestroy() used with an active zone"));
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KASSERT((z->zflags & ZONE_BOOT) == 0,
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("zdestroy() used with a zbootinit()'ed zone"));
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if (z->zflags & ZONE_INTERRUPT) {
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kmem_free(kernel_map, z->zkva, z->zpagemax * PAGE_SIZE);
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vm_object_deallocate(z->zobj);
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atomic_subtract_int(&zone_kmem_kvaspace,
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z->zpagemax * PAGE_SIZE);
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atomic_subtract_int(&zone_kmem_pages,
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z->zpagecount);
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cnt.v_wire_count -= z->zpagecount;
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} else {
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/*
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* This is evil h0h0 magic:
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* The items may be in z->zitems in a random oder; we have to
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* free the start of an allocated area, but do not want to save
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* extra information. Additionally, we may not access items that
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* were in a freed area.
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* This is achieved in the following way: the smallest address
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* is selected, and, after removing all items that are in a
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* range of z->zalloc * PAGE_SIZE (one allocation unit) from
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* it, kmem_free is called on it (since it is the smallest one,
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* it must be the start of an area). This is repeated until all
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* items are gone.
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*/
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nbytes = z->zalloc * PAGE_SIZE;
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nitems = nbytes / z->zsize;
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while (z->zitems != NULL) {
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/* Find minimal element. */
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item = min = z->zitems;
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while (item != NULL) {
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if (item < min)
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min = item;
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item = ((void **)item)[0];
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}
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/* Free. */
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itp = &z->zitems;
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i = 0;
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while (*itp != NULL && i < nitems) {
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if ((char *)*itp >= (char *)min &&
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(char *)*itp < (char *)min + nbytes) {
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*itp = ((void **)*itp)[0];
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i++;
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} else
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itp = &((void **)*itp)[0];
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}
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KASSERT(i == nitems, ("zdestroy(): corrupt zone"));
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/*
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* We can allocate from kmem_map (kmem_malloc) or
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* kernel_map (kmem_alloc).
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* kmem_map is a submap of kernel_map, so we can use
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* vm_map_lookup to retrieve the map we need to use.
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*/
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map = kernel_map;
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if (vm_map_lookup(&map, (vm_offset_t)min, VM_PROT_NONE,
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&entry, &obj, &pindex, &prot, &wired) !=
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KERN_SUCCESS)
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panic("zalloc mapping lost");
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/* Need to unlock. */
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vm_map_lookup_done(map, entry);
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if (map == kmem_map) {
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atomic_subtract_int(&zone_kmem_pages,
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z->zalloc);
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} else if (map == kernel_map) {
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atomic_subtract_int(&zone_kern_pages,
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z->zalloc);
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} else
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panic("zdestroy(): bad map");
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kmem_free(map, (vm_offset_t)min, nbytes);
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}
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}
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mtx_lock(&zone_mtx);
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SLIST_REMOVE(&zlist, z, vm_zone, zent);
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mtx_unlock(&zone_mtx);
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mtx_destroy(&z->zmtx);
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free(z, M_ZONE);
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}
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/*
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* Grow the specified zone to accomodate more items.
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*/
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static void *
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_zget(vm_zone_t z)
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{
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int i;
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vm_page_t m;
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int nitems, nbytes;
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void *item;
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KASSERT(z != NULL, ("invalid zone"));
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if (z->zflags & ZONE_INTERRUPT) {
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item = (char *) z->zkva + z->zpagecount * PAGE_SIZE;
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for (i = 0; ((i < z->zalloc) && (z->zpagecount < z->zpagemax));
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i++) {
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vm_offset_t zkva;
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m = vm_page_alloc(z->zobj, z->zpagecount,
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z->zallocflag);
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if (m == NULL)
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break;
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zkva = z->zkva + z->zpagecount * PAGE_SIZE;
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pmap_kenter(zkva, VM_PAGE_TO_PHYS(m));
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bzero((caddr_t) zkva, PAGE_SIZE);
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z->zpagecount++;
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atomic_add_int(&zone_kmem_pages, 1);
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cnt.v_wire_count++;
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}
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nitems = (i * PAGE_SIZE) / z->zsize;
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} else {
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/* Please check zdestroy() when changing this! */
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nbytes = z->zalloc * PAGE_SIZE;
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/*
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* Check to see if the kernel map is already locked. We could allow
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* for recursive locks, but that eliminates a valuable debugging
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* mechanism, and opens up the kernel map for potential corruption
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* by inconsistent data structure manipulation. We could also use
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* the interrupt allocation mechanism, but that has size limitations.
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* Luckily, we have kmem_map that is a submap of kernel map available
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* for memory allocation, and manipulation of that map doesn't affect
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* the kernel map structures themselves.
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*
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* We can wait, so just do normal map allocation in the appropriate
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* map.
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*/
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mtx_unlock(&z->zmtx);
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if (lockstatus(&kernel_map->lock, NULL)) {
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item = (void *) kmem_malloc(kmem_map, nbytes, M_WAITOK);
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if (item != NULL)
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atomic_add_int(&zone_kmem_pages, z->zalloc);
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} else {
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item = (void *) kmem_alloc(kernel_map, nbytes);
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if (item != NULL)
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atomic_add_int(&zone_kern_pages, z->zalloc);
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}
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if (item != NULL) {
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bzero(item, nbytes);
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} else {
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nbytes = 0;
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}
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nitems = nbytes / z->zsize;
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mtx_lock(&z->zmtx);
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}
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z->ztotal += nitems;
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/*
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* Save one for immediate allocation
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*/
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if (nitems != 0) {
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nitems -= 1;
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for (i = 0; i < nitems; i++) {
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((void **) item)[0] = z->zitems;
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#ifdef INVARIANTS
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((void **) item)[1] = ZENTRY_FREE;
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#endif
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z->zitems = item;
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(char *) item += z->zsize;
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}
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z->zfreecnt += nitems;
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z->znalloc++;
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} else if (z->zfreecnt > 0) {
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item = z->zitems;
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z->zitems = ((void **) item)[0];
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#ifdef INVARIANTS
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KASSERT(((void **) item)[1] == ZENTRY_FREE,
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("item is not free"));
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((void **) item)[1] = 0;
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#endif
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z->zfreecnt--;
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z->znalloc++;
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} else {
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item = NULL;
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}
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mtx_assert(&z->zmtx, MA_OWNED);
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return item;
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}
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/*
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* Allocates an item from the specified zone.
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*/
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void *
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zalloc(vm_zone_t z)
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{
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void *item;
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KASSERT(z != NULL, ("invalid zone"));
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mtx_lock(&z->zmtx);
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if (z->zfreecnt <= z->zfreemin) {
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item = _zget(z);
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goto out;
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}
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item = z->zitems;
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z->zitems = ((void **) item)[0];
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#ifdef INVARIANTS
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KASSERT(((void **) item)[1] == ZENTRY_FREE,
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("item is not free"));
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((void **) item)[1] = 0;
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#endif
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z->zfreecnt--;
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z->znalloc++;
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out:
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mtx_unlock(&z->zmtx);
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return item;
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}
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/*
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* Frees an item back to the specified zone.
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*/
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void
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zfree(vm_zone_t z, void *item)
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{
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KASSERT(z != NULL, ("invalid zone"));
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KASSERT(item != NULL, ("invalid item"));
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mtx_lock(&z->zmtx);
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((void **) item)[0] = z->zitems;
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#ifdef INVARIANTS
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KASSERT(((void **) item)[1] != ZENTRY_FREE,
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("item is already free"));
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((void **) item)[1] = (void *) ZENTRY_FREE;
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#endif
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z->zitems = item;
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z->zfreecnt++;
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mtx_unlock(&z->zmtx);
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}
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/*
|
|
* Sysctl handler for vm.zone
|
|
*/
|
|
static int
|
|
sysctl_vm_zone(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, len, cnt;
|
|
const int linesize = 128; /* conservative */
|
|
char *tmpbuf, *offset;
|
|
vm_zone_t z;
|
|
char *p;
|
|
|
|
cnt = 0;
|
|
mtx_lock(&zone_mtx);
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|
SLIST_FOREACH(z, &zlist, zent)
|
|
cnt++;
|
|
mtx_unlock(&zone_mtx);
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|
MALLOC(tmpbuf, char *, (cnt == 0 ? 1 : cnt) * linesize,
|
|
M_TEMP, M_WAITOK);
|
|
len = snprintf(tmpbuf, linesize,
|
|
"\nITEM SIZE LIMIT USED FREE REQUESTS\n\n");
|
|
if (cnt == 0)
|
|
tmpbuf[len - 1] = '\0';
|
|
error = SYSCTL_OUT(req, tmpbuf, cnt == 0 ? len-1 : len);
|
|
if (error || cnt == 0)
|
|
goto out;
|
|
offset = tmpbuf;
|
|
mtx_lock(&zone_mtx);
|
|
SLIST_FOREACH(z, &zlist, zent) {
|
|
if (cnt == 0) /* list may have changed size */
|
|
break;
|
|
mtx_lock(&z->zmtx);
|
|
len = snprintf(offset, linesize,
|
|
"%-12.12s %6.6u, %8.8u, %6.6u, %6.6u, %8.8u\n",
|
|
z->zname, z->zsize, z->zmax, (z->ztotal - z->zfreecnt),
|
|
z->zfreecnt, z->znalloc);
|
|
mtx_unlock(&z->zmtx);
|
|
for (p = offset + 12; p > offset && *p == ' '; --p)
|
|
/* nothing */ ;
|
|
p[1] = ':';
|
|
cnt--;
|
|
offset += len;
|
|
}
|
|
mtx_unlock(&zone_mtx);
|
|
*offset++ = '\0';
|
|
error = SYSCTL_OUT(req, tmpbuf, offset - tmpbuf);
|
|
out:
|
|
FREE(tmpbuf, M_TEMP);
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_OID(_vm, OID_AUTO, zone, CTLTYPE_STRING|CTLFLAG_RD,
|
|
NULL, 0, sysctl_vm_zone, "A", "Zone Info");
|
|
|
|
SYSCTL_INT(_vm, OID_AUTO, zone_kmem_pages, CTLFLAG_RD, &zone_kmem_pages, 0,
|
|
"Number of interrupt safe pages allocated by zone");
|
|
SYSCTL_INT(_vm, OID_AUTO, zone_kmem_kvaspace, CTLFLAG_RD, &zone_kmem_kvaspace, 0,
|
|
"KVA space allocated by zone");
|
|
SYSCTL_INT(_vm, OID_AUTO, zone_kern_pages, CTLFLAG_RD, &zone_kern_pages, 0,
|
|
"Number of non-interrupt safe pages allocated by zone");
|