5062 lines
124 KiB
C
5062 lines
124 KiB
C
/* $NetBSD: uvm_map.c,v 1.243 2007/10/15 11:24:30 yamt Exp $ */
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/*
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* Copyright (c) 1997 Charles D. Cranor and Washington University.
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* Copyright (c) 1991, 1993, The Regents of the University of California.
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*
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* All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* The Mach Operating System project at Carnegie-Mellon University.
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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, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Charles D. Cranor,
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* Washington University, the University of California, Berkeley and
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* its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)vm_map.c 8.3 (Berkeley) 1/12/94
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* from: Id: uvm_map.c,v 1.1.2.27 1998/02/07 01:16:54 chs Exp
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*
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*
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* Copyright (c) 1987, 1990 Carnegie-Mellon University.
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* All rights reserved.
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*
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* Permission to use, copy, modify and distribute this software and
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* its documentation is hereby granted, provided that both the copyright
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* notice and this permission notice appear in all copies of the
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* software, derivative works or modified versions, and any portions
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* thereof, and that both notices appear in supporting documentation.
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*
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* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
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* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
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* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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*
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* Carnegie Mellon requests users of this software to return to
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*
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* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
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* School of Computer Science
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* Carnegie Mellon University
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* Pittsburgh PA 15213-3890
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*
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* any improvements or extensions that they make and grant Carnegie the
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* rights to redistribute these changes.
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*/
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/*
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* uvm_map.c: uvm map operations
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: uvm_map.c,v 1.243 2007/10/15 11:24:30 yamt Exp $");
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#include "opt_ddb.h"
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#include "opt_uvmhist.h"
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#include "opt_uvm.h"
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#include "opt_sysv.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/mman.h>
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#include <sys/proc.h>
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#include <sys/malloc.h>
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#include <sys/pool.h>
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#include <sys/kernel.h>
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#include <sys/mount.h>
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#include <sys/vnode.h>
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#ifdef SYSVSHM
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#include <sys/shm.h>
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#endif
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#include <uvm/uvm.h>
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#undef RB_AUGMENT
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#define RB_AUGMENT(x) uvm_rb_augment(x)
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#ifdef DDB
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#include <uvm/uvm_ddb.h>
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#endif
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#if defined(UVMMAP_NOCOUNTERS)
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#define UVMMAP_EVCNT_DEFINE(name) /* nothing */
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#define UVMMAP_EVCNT_INCR(ev) /* nothing */
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#define UVMMAP_EVCNT_DECR(ev) /* nothing */
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#else /* defined(UVMMAP_NOCOUNTERS) */
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#include <sys/evcnt.h>
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#define UVMMAP_EVCNT_DEFINE(name) \
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struct evcnt uvmmap_evcnt_##name = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, \
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"uvmmap", #name); \
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EVCNT_ATTACH_STATIC(uvmmap_evcnt_##name);
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#define UVMMAP_EVCNT_INCR(ev) uvmmap_evcnt_##ev.ev_count++
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#define UVMMAP_EVCNT_DECR(ev) uvmmap_evcnt_##ev.ev_count--
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#endif /* defined(UVMMAP_NOCOUNTERS) */
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UVMMAP_EVCNT_DEFINE(ubackmerge)
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UVMMAP_EVCNT_DEFINE(uforwmerge)
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UVMMAP_EVCNT_DEFINE(ubimerge)
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UVMMAP_EVCNT_DEFINE(unomerge)
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UVMMAP_EVCNT_DEFINE(kbackmerge)
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UVMMAP_EVCNT_DEFINE(kforwmerge)
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UVMMAP_EVCNT_DEFINE(kbimerge)
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UVMMAP_EVCNT_DEFINE(knomerge)
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UVMMAP_EVCNT_DEFINE(map_call)
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UVMMAP_EVCNT_DEFINE(mlk_call)
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UVMMAP_EVCNT_DEFINE(mlk_hint)
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UVMMAP_EVCNT_DEFINE(uke_alloc)
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UVMMAP_EVCNT_DEFINE(uke_free)
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UVMMAP_EVCNT_DEFINE(ukh_alloc)
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UVMMAP_EVCNT_DEFINE(ukh_free)
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const char vmmapbsy[] = "vmmapbsy";
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/*
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* pool for vmspace structures.
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*/
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POOL_INIT(uvm_vmspace_pool, sizeof(struct vmspace), 0, 0, 0, "vmsppl",
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&pool_allocator_nointr, IPL_NONE);
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/*
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* pool for dynamically-allocated map entries.
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*/
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POOL_INIT(uvm_map_entry_pool, sizeof(struct vm_map_entry), 0, 0, 0, "vmmpepl",
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&pool_allocator_nointr, IPL_NONE);
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MALLOC_DEFINE(M_VMMAP, "VM map", "VM map structures");
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MALLOC_DEFINE(M_VMPMAP, "VM pmap", "VM pmap");
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#ifdef PMAP_GROWKERNEL
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/*
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* This global represents the end of the kernel virtual address
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* space. If we want to exceed this, we must grow the kernel
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* virtual address space dynamically.
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*
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* Note, this variable is locked by kernel_map's lock.
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*/
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vaddr_t uvm_maxkaddr;
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#endif
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/*
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* macros
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*/
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/*
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* VM_MAP_USE_KMAPENT: determine if uvm_kmapent_alloc/free is used
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* for the vm_map.
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*/
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extern struct vm_map *pager_map; /* XXX */
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#define VM_MAP_USE_KMAPENT_FLAGS(flags) \
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(((flags) & VM_MAP_INTRSAFE) != 0)
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#define VM_MAP_USE_KMAPENT(map) \
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(VM_MAP_USE_KMAPENT_FLAGS((map)->flags) || (map) == kernel_map)
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/*
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* UVM_ET_ISCOMPATIBLE: check some requirements for map entry merging
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*/
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#define UVM_ET_ISCOMPATIBLE(ent, type, uobj, meflags, \
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prot, maxprot, inh, adv, wire) \
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((ent)->etype == (type) && \
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(((ent)->flags ^ (meflags)) & (UVM_MAP_NOMERGE | UVM_MAP_QUANTUM)) \
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== 0 && \
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(ent)->object.uvm_obj == (uobj) && \
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(ent)->protection == (prot) && \
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(ent)->max_protection == (maxprot) && \
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(ent)->inheritance == (inh) && \
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(ent)->advice == (adv) && \
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(ent)->wired_count == (wire))
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/*
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* uvm_map_entry_link: insert entry into a map
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*
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* => map must be locked
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*/
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#define uvm_map_entry_link(map, after_where, entry) do { \
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uvm_mapent_check(entry); \
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(map)->nentries++; \
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(entry)->prev = (after_where); \
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(entry)->next = (after_where)->next; \
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(entry)->prev->next = (entry); \
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(entry)->next->prev = (entry); \
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uvm_rb_insert((map), (entry)); \
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} while (/*CONSTCOND*/ 0)
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/*
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* uvm_map_entry_unlink: remove entry from a map
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*
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* => map must be locked
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*/
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#define uvm_map_entry_unlink(map, entry) do { \
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KASSERT((entry) != (map)->first_free); \
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KASSERT((entry) != (map)->hint); \
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uvm_mapent_check(entry); \
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(map)->nentries--; \
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(entry)->next->prev = (entry)->prev; \
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(entry)->prev->next = (entry)->next; \
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uvm_rb_remove((map), (entry)); \
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} while (/*CONSTCOND*/ 0)
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/*
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* SAVE_HINT: saves the specified entry as the hint for future lookups.
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*
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* => map need not be locked (protected by hint_lock).
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*/
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#define SAVE_HINT(map,check,value) do { \
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mutex_enter(&(map)->hint_lock); \
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if ((map)->hint == (check)) \
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(map)->hint = (value); \
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mutex_exit(&(map)->hint_lock); \
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} while (/*CONSTCOND*/ 0)
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/*
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* clear_hints: ensure that hints don't point to the entry.
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*
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* => map must be write-locked.
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*/
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static void
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clear_hints(struct vm_map *map, struct vm_map_entry *ent)
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{
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SAVE_HINT(map, ent, ent->prev);
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if (map->first_free == ent) {
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map->first_free = ent->prev;
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}
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}
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/*
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* VM_MAP_RANGE_CHECK: check and correct range
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*
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* => map must at least be read locked
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*/
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#define VM_MAP_RANGE_CHECK(map, start, end) do { \
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if (start < vm_map_min(map)) \
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start = vm_map_min(map); \
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if (end > vm_map_max(map)) \
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end = vm_map_max(map); \
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if (start > end) \
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start = end; \
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} while (/*CONSTCOND*/ 0)
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/*
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* local prototypes
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*/
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static struct vm_map_entry *
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uvm_mapent_alloc(struct vm_map *, int);
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static struct vm_map_entry *
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uvm_mapent_alloc_split(struct vm_map *,
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const struct vm_map_entry *, int,
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struct uvm_mapent_reservation *);
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static void uvm_mapent_copy(struct vm_map_entry *, struct vm_map_entry *);
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static void uvm_mapent_free(struct vm_map_entry *);
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#if defined(DEBUG)
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static void _uvm_mapent_check(const struct vm_map_entry *, const char *,
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int);
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#define uvm_mapent_check(map) _uvm_mapent_check(map, __FILE__, __LINE__)
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#else /* defined(DEBUG) */
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#define uvm_mapent_check(e) /* nothing */
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#endif /* defined(DEBUG) */
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static struct vm_map_entry *
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uvm_kmapent_alloc(struct vm_map *, int);
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static void uvm_kmapent_free(struct vm_map_entry *);
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static vsize_t uvm_kmapent_overhead(vsize_t);
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static void uvm_map_entry_unwire(struct vm_map *, struct vm_map_entry *);
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static void uvm_map_reference_amap(struct vm_map_entry *, int);
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static int uvm_map_space_avail(vaddr_t *, vsize_t, voff_t, vsize_t, int,
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struct vm_map_entry *);
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static void uvm_map_unreference_amap(struct vm_map_entry *, int);
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int _uvm_map_sanity(struct vm_map *);
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int _uvm_tree_sanity(struct vm_map *);
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static vsize_t uvm_rb_subtree_space(const struct vm_map_entry *);
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static inline int
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uvm_compare(const struct vm_map_entry *a, const struct vm_map_entry *b)
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{
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if (a->start < b->start)
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return (-1);
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else if (a->start > b->start)
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return (1);
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return (0);
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}
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static inline void
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uvm_rb_augment(struct vm_map_entry *entry)
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{
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entry->space = uvm_rb_subtree_space(entry);
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}
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RB_PROTOTYPE(uvm_tree, vm_map_entry, rb_entry, uvm_compare);
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RB_GENERATE(uvm_tree, vm_map_entry, rb_entry, uvm_compare);
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static inline vsize_t
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uvm_rb_space(const struct vm_map *map, const struct vm_map_entry *entry)
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{
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/* XXX map is not used */
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KASSERT(entry->next != NULL);
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return entry->next->start - entry->end;
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}
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static vsize_t
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uvm_rb_subtree_space(const struct vm_map_entry *entry)
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{
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vaddr_t space, tmp;
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space = entry->ownspace;
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if (RB_LEFT(entry, rb_entry)) {
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tmp = RB_LEFT(entry, rb_entry)->space;
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if (tmp > space)
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space = tmp;
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}
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if (RB_RIGHT(entry, rb_entry)) {
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tmp = RB_RIGHT(entry, rb_entry)->space;
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if (tmp > space)
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space = tmp;
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}
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return (space);
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}
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static inline void
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uvm_rb_fixup(struct vm_map *map, struct vm_map_entry *entry)
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{
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/* We need to traverse to the very top */
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do {
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entry->ownspace = uvm_rb_space(map, entry);
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entry->space = uvm_rb_subtree_space(entry);
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} while ((entry = RB_PARENT(entry, rb_entry)) != NULL);
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}
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static void
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uvm_rb_insert(struct vm_map *map, struct vm_map_entry *entry)
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{
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vaddr_t space = uvm_rb_space(map, entry);
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struct vm_map_entry *tmp;
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entry->ownspace = entry->space = space;
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tmp = RB_INSERT(uvm_tree, &(map)->rbhead, entry);
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#ifdef DIAGNOSTIC
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if (tmp != NULL)
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panic("uvm_rb_insert: duplicate entry?");
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#endif
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uvm_rb_fixup(map, entry);
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if (entry->prev != &map->header)
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uvm_rb_fixup(map, entry->prev);
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}
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static void
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uvm_rb_remove(struct vm_map *map, struct vm_map_entry *entry)
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{
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struct vm_map_entry *parent;
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parent = RB_PARENT(entry, rb_entry);
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RB_REMOVE(uvm_tree, &(map)->rbhead, entry);
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if (entry->prev != &map->header)
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uvm_rb_fixup(map, entry->prev);
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if (parent)
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uvm_rb_fixup(map, parent);
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}
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#if defined(DEBUG)
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int uvm_debug_check_map = 0;
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int uvm_debug_check_rbtree = 0;
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#define uvm_map_check(map, name) \
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_uvm_map_check((map), (name), __FILE__, __LINE__)
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static void
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_uvm_map_check(struct vm_map *map, const char *name,
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const char *file, int line)
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{
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if ((uvm_debug_check_map && _uvm_map_sanity(map)) ||
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(uvm_debug_check_rbtree && _uvm_tree_sanity(map))) {
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panic("uvm_map_check failed: \"%s\" map=%p (%s:%d)",
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name, map, file, line);
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}
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}
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#else /* defined(DEBUG) */
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#define uvm_map_check(map, name) /* nothing */
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#endif /* defined(DEBUG) */
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#if defined(DEBUG) || defined(DDB)
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int
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_uvm_map_sanity(struct vm_map *map)
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{
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bool first_free_found = false;
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bool hint_found = false;
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const struct vm_map_entry *e;
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e = &map->header;
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for (;;) {
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if (map->first_free == e) {
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first_free_found = true;
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} else if (!first_free_found && e->next->start > e->end) {
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printf("first_free %p should be %p\n",
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map->first_free, e);
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return -1;
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}
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if (map->hint == e) {
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hint_found = true;
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}
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e = e->next;
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if (e == &map->header) {
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break;
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}
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}
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if (!first_free_found) {
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printf("stale first_free\n");
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return -1;
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}
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if (!hint_found) {
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printf("stale hint\n");
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return -1;
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}
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return 0;
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}
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int
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_uvm_tree_sanity(struct vm_map *map)
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{
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struct vm_map_entry *tmp, *trtmp;
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int n = 0, i = 1;
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RB_FOREACH(tmp, uvm_tree, &map->rbhead) {
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if (tmp->ownspace != uvm_rb_space(map, tmp)) {
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printf("%d/%d ownspace %lx != %lx %s\n",
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n + 1, map->nentries,
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(ulong)tmp->ownspace, (ulong)uvm_rb_space(map, tmp),
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tmp->next == &map->header ? "(last)" : "");
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goto error;
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}
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}
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trtmp = NULL;
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RB_FOREACH(tmp, uvm_tree, &map->rbhead) {
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if (tmp->space != uvm_rb_subtree_space(tmp)) {
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printf("space %lx != %lx\n",
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(ulong)tmp->space,
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(ulong)uvm_rb_subtree_space(tmp));
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goto error;
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}
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if (trtmp != NULL && trtmp->start >= tmp->start) {
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printf("corrupt: 0x%lx >= 0x%lx\n",
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trtmp->start, tmp->start);
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goto error;
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}
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n++;
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trtmp = tmp;
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}
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|
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if (n != map->nentries) {
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printf("nentries: %d vs %d\n", n, map->nentries);
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|
goto error;
|
|
}
|
|
|
|
for (tmp = map->header.next; tmp && tmp != &map->header;
|
|
tmp = tmp->next, i++) {
|
|
trtmp = RB_FIND(uvm_tree, &map->rbhead, tmp);
|
|
if (trtmp != tmp) {
|
|
printf("lookup: %d: %p - %p: %p\n", i, tmp, trtmp,
|
|
RB_PARENT(tmp, rb_entry));
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
return (0);
|
|
error:
|
|
return (-1);
|
|
}
|
|
#endif /* defined(DEBUG) || defined(DDB) */
|
|
|
|
#ifdef DIAGNOSTIC
|
|
static struct vm_map *uvm_kmapent_map(struct vm_map_entry *);
|
|
#endif
|
|
|
|
/*
|
|
* vm_map_lock: acquire an exclusive (write) lock on a map.
|
|
*
|
|
* => Note that "intrsafe" maps use only exclusive, spin locks.
|
|
*
|
|
* => The locking protocol provides for guaranteed upgrade from shared ->
|
|
* exclusive by whichever thread currently has the map marked busy.
|
|
* See "LOCKING PROTOCOL NOTES" in uvm_map.h. This is horrible; among
|
|
* other problems, it defeats any fairness guarantees provided by RW
|
|
* locks.
|
|
*/
|
|
|
|
void
|
|
vm_map_lock(struct vm_map *map)
|
|
{
|
|
|
|
if ((map->flags & VM_MAP_INTRSAFE) != 0) {
|
|
mutex_spin_enter(&map->mutex);
|
|
return;
|
|
}
|
|
|
|
for (;;) {
|
|
rw_enter(&map->lock, RW_WRITER);
|
|
if (map->busy == NULL)
|
|
break;
|
|
KASSERT(map->busy != curlwp);
|
|
mutex_enter(&map->misc_lock);
|
|
rw_exit(&map->lock);
|
|
cv_wait(&map->cv, &map->misc_lock);
|
|
mutex_exit(&map->misc_lock);
|
|
}
|
|
|
|
map->timestamp++;
|
|
}
|
|
|
|
/*
|
|
* vm_map_lock_try: try to lock a map, failing if it is already locked.
|
|
*/
|
|
|
|
bool
|
|
vm_map_lock_try(struct vm_map *map)
|
|
{
|
|
|
|
if ((map->flags & VM_MAP_INTRSAFE) != 0)
|
|
return mutex_tryenter(&map->mutex);
|
|
if (!rw_tryenter(&map->lock, RW_WRITER))
|
|
return false;
|
|
if (map->busy != NULL) {
|
|
rw_exit(&map->lock);
|
|
return false;
|
|
}
|
|
|
|
map->timestamp++;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* vm_map_unlock: release an exclusive lock on a map.
|
|
*/
|
|
|
|
void
|
|
vm_map_unlock(struct vm_map *map)
|
|
{
|
|
|
|
if ((map->flags & VM_MAP_INTRSAFE) != 0)
|
|
mutex_spin_exit(&map->mutex);
|
|
else {
|
|
KASSERT(rw_write_held(&map->lock));
|
|
rw_exit(&map->lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vm_map_upgrade: upgrade a shared lock to an exclusive lock.
|
|
*
|
|
* => the caller must hold the map busy
|
|
*/
|
|
|
|
void
|
|
vm_map_upgrade(struct vm_map *map)
|
|
{
|
|
|
|
KASSERT(rw_read_held(&map->lock));
|
|
KASSERT(map->busy == curlwp);
|
|
|
|
if (rw_tryupgrade(&map->lock))
|
|
return;
|
|
|
|
rw_exit(&map->lock);
|
|
rw_enter(&map->lock, RW_WRITER);
|
|
}
|
|
|
|
/*
|
|
* vm_map_unbusy: mark the map as unbusy, and wake any waiters that
|
|
* want an exclusive lock.
|
|
*/
|
|
|
|
void
|
|
vm_map_unbusy(struct vm_map *map)
|
|
{
|
|
|
|
KASSERT(rw_lock_held(&map->lock));
|
|
KASSERT(map->busy == curlwp);
|
|
|
|
/*
|
|
* Safe to clear 'busy' and 'waiters' with only a read lock held:
|
|
*
|
|
* o they can only be set with a write lock held
|
|
* o writers are blocked out with a read or write hold
|
|
* o at any time, only one thread owns the set of values
|
|
*/
|
|
map->busy = NULL;
|
|
mutex_enter(&map->misc_lock);
|
|
cv_broadcast(&map->cv);
|
|
mutex_exit(&map->misc_lock);
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_alloc: allocate a map entry
|
|
*/
|
|
|
|
static struct vm_map_entry *
|
|
uvm_mapent_alloc(struct vm_map *map, int flags)
|
|
{
|
|
struct vm_map_entry *me;
|
|
int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK;
|
|
UVMHIST_FUNC("uvm_mapent_alloc"); UVMHIST_CALLED(maphist);
|
|
|
|
if (VM_MAP_USE_KMAPENT(map)) {
|
|
me = uvm_kmapent_alloc(map, flags);
|
|
} else {
|
|
me = pool_get(&uvm_map_entry_pool, pflags);
|
|
if (__predict_false(me == NULL))
|
|
return NULL;
|
|
me->flags = 0;
|
|
}
|
|
|
|
UVMHIST_LOG(maphist, "<- new entry=0x%x [kentry=%d]", me,
|
|
((map->flags & VM_MAP_INTRSAFE) != 0 || map == kernel_map), 0, 0);
|
|
return (me);
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_alloc_split: allocate a map entry for clipping.
|
|
*/
|
|
|
|
static struct vm_map_entry *
|
|
uvm_mapent_alloc_split(struct vm_map *map,
|
|
const struct vm_map_entry *old_entry, int flags,
|
|
struct uvm_mapent_reservation *umr)
|
|
{
|
|
struct vm_map_entry *me;
|
|
|
|
KASSERT(!VM_MAP_USE_KMAPENT(map) ||
|
|
(old_entry->flags & UVM_MAP_QUANTUM) || !UMR_EMPTY(umr));
|
|
|
|
if (old_entry->flags & UVM_MAP_QUANTUM) {
|
|
struct vm_map_kernel *vmk = vm_map_to_kernel(map);
|
|
|
|
mutex_spin_enter(&uvm_kentry_lock);
|
|
me = vmk->vmk_merged_entries;
|
|
KASSERT(me);
|
|
vmk->vmk_merged_entries = me->next;
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
KASSERT(me->flags & UVM_MAP_QUANTUM);
|
|
} else {
|
|
me = uvm_mapent_alloc(map, flags);
|
|
}
|
|
|
|
return me;
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_free: free map entry
|
|
*/
|
|
|
|
static void
|
|
uvm_mapent_free(struct vm_map_entry *me)
|
|
{
|
|
UVMHIST_FUNC("uvm_mapent_free"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"<- freeing map entry=0x%x [flags=%d]",
|
|
me, me->flags, 0, 0);
|
|
if (me->flags & UVM_MAP_KERNEL) {
|
|
uvm_kmapent_free(me);
|
|
} else {
|
|
pool_put(&uvm_map_entry_pool, me);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_free_merged: free merged map entry
|
|
*
|
|
* => keep the entry if needed.
|
|
* => caller shouldn't hold map locked if VM_MAP_USE_KMAPENT(map) is true.
|
|
*/
|
|
|
|
static void
|
|
uvm_mapent_free_merged(struct vm_map *map, struct vm_map_entry *me)
|
|
{
|
|
|
|
KASSERT(!(me->flags & UVM_MAP_KERNEL) || uvm_kmapent_map(me) == map);
|
|
|
|
if (me->flags & UVM_MAP_QUANTUM) {
|
|
/*
|
|
* keep this entry for later splitting.
|
|
*/
|
|
struct vm_map_kernel *vmk;
|
|
|
|
KASSERT(VM_MAP_IS_KERNEL(map));
|
|
KASSERT(!VM_MAP_USE_KMAPENT(map) ||
|
|
(me->flags & UVM_MAP_KERNEL));
|
|
|
|
vmk = vm_map_to_kernel(map);
|
|
mutex_spin_enter(&uvm_kentry_lock);
|
|
me->next = vmk->vmk_merged_entries;
|
|
vmk->vmk_merged_entries = me;
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
} else {
|
|
uvm_mapent_free(me);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_copy: copy a map entry, preserving flags
|
|
*/
|
|
|
|
static inline void
|
|
uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst)
|
|
{
|
|
|
|
memcpy(dst, src, ((char *)&src->uvm_map_entry_stop_copy) -
|
|
((char *)src));
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_overhead: calculate maximum kva overhead necessary for
|
|
* map entries.
|
|
*
|
|
* => size and flags are the same as uvm_km_suballoc's ones.
|
|
*/
|
|
|
|
vsize_t
|
|
uvm_mapent_overhead(vsize_t size, int flags)
|
|
{
|
|
|
|
if (VM_MAP_USE_KMAPENT_FLAGS(flags)) {
|
|
return uvm_kmapent_overhead(size);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#if defined(DEBUG)
|
|
static void
|
|
_uvm_mapent_check(const struct vm_map_entry *entry, const char *file, int line)
|
|
{
|
|
|
|
if (entry->start >= entry->end) {
|
|
goto bad;
|
|
}
|
|
if (UVM_ET_ISOBJ(entry)) {
|
|
if (entry->object.uvm_obj == NULL) {
|
|
goto bad;
|
|
}
|
|
} else if (UVM_ET_ISSUBMAP(entry)) {
|
|
if (entry->object.sub_map == NULL) {
|
|
goto bad;
|
|
}
|
|
} else {
|
|
if (entry->object.uvm_obj != NULL ||
|
|
entry->object.sub_map != NULL) {
|
|
goto bad;
|
|
}
|
|
}
|
|
if (!UVM_ET_ISOBJ(entry)) {
|
|
if (entry->offset != 0) {
|
|
goto bad;
|
|
}
|
|
}
|
|
|
|
return;
|
|
|
|
bad:
|
|
panic("%s: bad entry %p (%s:%d)", __func__, entry, file, line);
|
|
}
|
|
#endif /* defined(DEBUG) */
|
|
|
|
/*
|
|
* uvm_map_entry_unwire: unwire a map entry
|
|
*
|
|
* => map should be locked by caller
|
|
*/
|
|
|
|
static inline void
|
|
uvm_map_entry_unwire(struct vm_map *map, struct vm_map_entry *entry)
|
|
{
|
|
|
|
entry->wired_count = 0;
|
|
uvm_fault_unwire_locked(map, entry->start, entry->end);
|
|
}
|
|
|
|
|
|
/*
|
|
* wrapper for calling amap_ref()
|
|
*/
|
|
static inline void
|
|
uvm_map_reference_amap(struct vm_map_entry *entry, int flags)
|
|
{
|
|
|
|
amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff,
|
|
(entry->end - entry->start) >> PAGE_SHIFT, flags);
|
|
}
|
|
|
|
|
|
/*
|
|
* wrapper for calling amap_unref()
|
|
*/
|
|
static inline void
|
|
uvm_map_unreference_amap(struct vm_map_entry *entry, int flags)
|
|
{
|
|
|
|
amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff,
|
|
(entry->end - entry->start) >> PAGE_SHIFT, flags);
|
|
}
|
|
|
|
|
|
/*
|
|
* uvm_map_init: init mapping system at boot time. note that we allocate
|
|
* and init the static pool of struct vm_map_entry *'s for the kernel here.
|
|
*/
|
|
|
|
void
|
|
uvm_map_init(void)
|
|
{
|
|
#if defined(UVMHIST)
|
|
static struct uvm_history_ent maphistbuf[100];
|
|
static struct uvm_history_ent pdhistbuf[100];
|
|
#endif
|
|
|
|
/*
|
|
* first, init logging system.
|
|
*/
|
|
|
|
UVMHIST_FUNC("uvm_map_init");
|
|
UVMHIST_INIT_STATIC(maphist, maphistbuf);
|
|
UVMHIST_INIT_STATIC(pdhist, pdhistbuf);
|
|
UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0);
|
|
|
|
/*
|
|
* initialize the global lock for kernel map entry.
|
|
*/
|
|
|
|
mutex_init(&uvm_kentry_lock, MUTEX_DRIVER, IPL_VM);
|
|
}
|
|
|
|
/*
|
|
* clippers
|
|
*/
|
|
|
|
/*
|
|
* uvm_mapent_splitadj: adjust map entries for splitting, after uvm_mapent_copy.
|
|
*/
|
|
|
|
static void
|
|
uvm_mapent_splitadj(struct vm_map_entry *entry1, struct vm_map_entry *entry2,
|
|
vaddr_t splitat)
|
|
{
|
|
vaddr_t adj;
|
|
|
|
KASSERT(entry1->start < splitat);
|
|
KASSERT(splitat < entry1->end);
|
|
|
|
adj = splitat - entry1->start;
|
|
entry1->end = entry2->start = splitat;
|
|
|
|
if (entry1->aref.ar_amap) {
|
|
amap_splitref(&entry1->aref, &entry2->aref, adj);
|
|
}
|
|
if (UVM_ET_ISSUBMAP(entry1)) {
|
|
/* ... unlikely to happen, but play it safe */
|
|
uvm_map_reference(entry1->object.sub_map);
|
|
} else if (UVM_ET_ISOBJ(entry1)) {
|
|
KASSERT(entry1->object.uvm_obj != NULL); /* suppress coverity */
|
|
entry2->offset += adj;
|
|
if (entry1->object.uvm_obj->pgops &&
|
|
entry1->object.uvm_obj->pgops->pgo_reference)
|
|
entry1->object.uvm_obj->pgops->pgo_reference(
|
|
entry1->object.uvm_obj);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_map_clip_start: ensure that the entry begins at or after
|
|
* the starting address, if it doesn't we split the entry.
|
|
*
|
|
* => caller should use UVM_MAP_CLIP_START macro rather than calling
|
|
* this directly
|
|
* => map must be locked by caller
|
|
*/
|
|
|
|
void
|
|
uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry,
|
|
vaddr_t start, struct uvm_mapent_reservation *umr)
|
|
{
|
|
struct vm_map_entry *new_entry;
|
|
|
|
/* uvm_map_simplify_entry(map, entry); */ /* XXX */
|
|
|
|
uvm_map_check(map, "clip_start entry");
|
|
uvm_mapent_check(entry);
|
|
|
|
/*
|
|
* Split off the front portion. note that we must insert the new
|
|
* entry BEFORE this one, so that this entry has the specified
|
|
* starting address.
|
|
*/
|
|
new_entry = uvm_mapent_alloc_split(map, entry, 0, umr);
|
|
uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */
|
|
uvm_mapent_splitadj(new_entry, entry, start);
|
|
uvm_map_entry_link(map, entry->prev, new_entry);
|
|
|
|
uvm_map_check(map, "clip_start leave");
|
|
}
|
|
|
|
/*
|
|
* uvm_map_clip_end: ensure that the entry ends at or before
|
|
* the ending address, if it does't we split the reference
|
|
*
|
|
* => caller should use UVM_MAP_CLIP_END macro rather than calling
|
|
* this directly
|
|
* => map must be locked by caller
|
|
*/
|
|
|
|
void
|
|
uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t end,
|
|
struct uvm_mapent_reservation *umr)
|
|
{
|
|
struct vm_map_entry *new_entry;
|
|
|
|
uvm_map_check(map, "clip_end entry");
|
|
uvm_mapent_check(entry);
|
|
|
|
/*
|
|
* Create a new entry and insert it
|
|
* AFTER the specified entry
|
|
*/
|
|
new_entry = uvm_mapent_alloc_split(map, entry, 0, umr);
|
|
uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */
|
|
uvm_mapent_splitadj(entry, new_entry, end);
|
|
uvm_map_entry_link(map, entry, new_entry);
|
|
|
|
uvm_map_check(map, "clip_end leave");
|
|
}
|
|
|
|
static void
|
|
vm_map_drain(struct vm_map *map, uvm_flag_t flags)
|
|
{
|
|
|
|
if (!VM_MAP_IS_KERNEL(map)) {
|
|
return;
|
|
}
|
|
|
|
uvm_km_va_drain(map, flags);
|
|
}
|
|
|
|
/*
|
|
* M A P - m a i n e n t r y p o i n t
|
|
*/
|
|
/*
|
|
* uvm_map: establish a valid mapping in a map
|
|
*
|
|
* => assume startp is page aligned.
|
|
* => assume size is a multiple of PAGE_SIZE.
|
|
* => assume sys_mmap provides enough of a "hint" to have us skip
|
|
* over text/data/bss area.
|
|
* => map must be unlocked (we will lock it)
|
|
* => <uobj,uoffset> value meanings (4 cases):
|
|
* [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER
|
|
* [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER
|
|
* [3] <uobj,uoffset> == normal mapping
|
|
* [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA
|
|
*
|
|
* case [4] is for kernel mappings where we don't know the offset until
|
|
* we've found a virtual address. note that kernel object offsets are
|
|
* always relative to vm_map_min(kernel_map).
|
|
*
|
|
* => if `align' is non-zero, we align the virtual address to the specified
|
|
* alignment.
|
|
* this is provided as a mechanism for large pages.
|
|
*
|
|
* => XXXCDC: need way to map in external amap?
|
|
*/
|
|
|
|
int
|
|
uvm_map(struct vm_map *map, vaddr_t *startp /* IN/OUT */, vsize_t size,
|
|
struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags)
|
|
{
|
|
struct uvm_map_args args;
|
|
struct vm_map_entry *new_entry;
|
|
int error;
|
|
|
|
KASSERT((flags & UVM_FLAG_QUANTUM) == 0 || VM_MAP_IS_KERNEL(map));
|
|
KASSERT((size & PAGE_MASK) == 0);
|
|
|
|
/*
|
|
* for pager_map, allocate the new entry first to avoid sleeping
|
|
* for memory while we have the map locked.
|
|
*
|
|
* besides, because we allocates entries for in-kernel maps
|
|
* a bit differently (cf. uvm_kmapent_alloc/free), we need to
|
|
* allocate them before locking the map.
|
|
*/
|
|
|
|
new_entry = NULL;
|
|
if (VM_MAP_USE_KMAPENT(map) || (flags & UVM_FLAG_QUANTUM) ||
|
|
map == pager_map) {
|
|
new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT));
|
|
if (__predict_false(new_entry == NULL))
|
|
return ENOMEM;
|
|
if (flags & UVM_FLAG_QUANTUM)
|
|
new_entry->flags |= UVM_MAP_QUANTUM;
|
|
}
|
|
if (map == pager_map)
|
|
flags |= UVM_FLAG_NOMERGE;
|
|
|
|
error = uvm_map_prepare(map, *startp, size, uobj, uoffset, align,
|
|
flags, &args);
|
|
if (!error) {
|
|
error = uvm_map_enter(map, &args, new_entry);
|
|
*startp = args.uma_start;
|
|
} else if (new_entry) {
|
|
uvm_mapent_free(new_entry);
|
|
}
|
|
|
|
#if defined(DEBUG)
|
|
if (!error && VM_MAP_IS_KERNEL(map)) {
|
|
uvm_km_check_empty(*startp, *startp + size,
|
|
(map->flags & VM_MAP_INTRSAFE) != 0);
|
|
}
|
|
#endif /* defined(DEBUG) */
|
|
|
|
return error;
|
|
}
|
|
|
|
int
|
|
uvm_map_prepare(struct vm_map *map, vaddr_t start, vsize_t size,
|
|
struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags,
|
|
struct uvm_map_args *args)
|
|
{
|
|
struct vm_map_entry *prev_entry;
|
|
vm_prot_t prot = UVM_PROTECTION(flags);
|
|
vm_prot_t maxprot = UVM_MAXPROTECTION(flags);
|
|
|
|
UVMHIST_FUNC("uvm_map_prepare");
|
|
UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, "(map=0x%x, start=0x%x, size=%d, flags=0x%x)",
|
|
map, start, size, flags);
|
|
UVMHIST_LOG(maphist, " uobj/offset 0x%x/%d", uobj, uoffset,0,0);
|
|
|
|
/*
|
|
* detect a popular device driver bug.
|
|
*/
|
|
|
|
KASSERT(doing_shutdown || curlwp != NULL ||
|
|
(map->flags & VM_MAP_INTRSAFE));
|
|
|
|
/*
|
|
* zero-sized mapping doesn't make any sense.
|
|
*/
|
|
KASSERT(size > 0);
|
|
|
|
KASSERT((~flags & (UVM_FLAG_NOWAIT | UVM_FLAG_WAITVA)) != 0);
|
|
|
|
uvm_map_check(map, "map entry");
|
|
|
|
/*
|
|
* check sanity of protection code
|
|
*/
|
|
|
|
if ((prot & maxprot) != prot) {
|
|
UVMHIST_LOG(maphist, "<- prot. failure: prot=0x%x, max=0x%x",
|
|
prot, maxprot,0,0);
|
|
return EACCES;
|
|
}
|
|
|
|
/*
|
|
* figure out where to put new VM range
|
|
*/
|
|
|
|
retry:
|
|
if (vm_map_lock_try(map) == false) {
|
|
if (flags & UVM_FLAG_TRYLOCK) {
|
|
return EAGAIN;
|
|
}
|
|
vm_map_lock(map); /* could sleep here */
|
|
}
|
|
prev_entry = uvm_map_findspace(map, start, size, &start,
|
|
uobj, uoffset, align, flags);
|
|
if (prev_entry == NULL) {
|
|
unsigned int timestamp;
|
|
|
|
timestamp = map->timestamp;
|
|
UVMHIST_LOG(maphist,"waiting va timestamp=0x%x",
|
|
timestamp,0,0,0);
|
|
map->flags |= VM_MAP_WANTVA;
|
|
vm_map_unlock(map);
|
|
|
|
/*
|
|
* try to reclaim kva and wait until someone does unmap.
|
|
* fragile locking here, so we awaken every second to
|
|
* recheck the condition.
|
|
*/
|
|
|
|
vm_map_drain(map, flags);
|
|
|
|
mutex_enter(&map->misc_lock);
|
|
while ((map->flags & VM_MAP_WANTVA) != 0 &&
|
|
map->timestamp == timestamp) {
|
|
if ((flags & UVM_FLAG_WAITVA) == 0) {
|
|
mutex_exit(&map->misc_lock);
|
|
UVMHIST_LOG(maphist,
|
|
"<- uvm_map_findspace failed!", 0,0,0,0);
|
|
return ENOMEM;
|
|
} else {
|
|
cv_timedwait(&map->cv, &map->misc_lock, hz);
|
|
}
|
|
}
|
|
mutex_exit(&map->misc_lock);
|
|
goto retry;
|
|
}
|
|
|
|
#ifdef PMAP_GROWKERNEL
|
|
/*
|
|
* If the kernel pmap can't map the requested space,
|
|
* then allocate more resources for it.
|
|
*/
|
|
if (map == kernel_map && uvm_maxkaddr < (start + size))
|
|
uvm_maxkaddr = pmap_growkernel(start + size);
|
|
#endif
|
|
|
|
UVMMAP_EVCNT_INCR(map_call);
|
|
|
|
/*
|
|
* if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER
|
|
* [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in
|
|
* either case we want to zero it before storing it in the map entry
|
|
* (because it looks strange and confusing when debugging...)
|
|
*
|
|
* if uobj is not null
|
|
* if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping
|
|
* and we do not need to change uoffset.
|
|
* if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset
|
|
* now (based on the starting address of the map). this case is
|
|
* for kernel object mappings where we don't know the offset until
|
|
* the virtual address is found (with uvm_map_findspace). the
|
|
* offset is the distance we are from the start of the map.
|
|
*/
|
|
|
|
if (uobj == NULL) {
|
|
uoffset = 0;
|
|
} else {
|
|
if (uoffset == UVM_UNKNOWN_OFFSET) {
|
|
KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj));
|
|
uoffset = start - vm_map_min(kernel_map);
|
|
}
|
|
}
|
|
|
|
args->uma_flags = flags;
|
|
args->uma_prev = prev_entry;
|
|
args->uma_start = start;
|
|
args->uma_size = size;
|
|
args->uma_uobj = uobj;
|
|
args->uma_uoffset = uoffset;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
uvm_map_enter(struct vm_map *map, const struct uvm_map_args *args,
|
|
struct vm_map_entry *new_entry)
|
|
{
|
|
struct vm_map_entry *prev_entry = args->uma_prev;
|
|
struct vm_map_entry *dead = NULL;
|
|
|
|
const uvm_flag_t flags = args->uma_flags;
|
|
const vm_prot_t prot = UVM_PROTECTION(flags);
|
|
const vm_prot_t maxprot = UVM_MAXPROTECTION(flags);
|
|
const vm_inherit_t inherit = UVM_INHERIT(flags);
|
|
const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ?
|
|
AMAP_EXTEND_NOWAIT : 0;
|
|
const int advice = UVM_ADVICE(flags);
|
|
const int meflagval = (flags & UVM_FLAG_QUANTUM) ?
|
|
UVM_MAP_QUANTUM : 0;
|
|
|
|
vaddr_t start = args->uma_start;
|
|
vsize_t size = args->uma_size;
|
|
struct uvm_object *uobj = args->uma_uobj;
|
|
voff_t uoffset = args->uma_uoffset;
|
|
|
|
const int kmap = (vm_map_pmap(map) == pmap_kernel());
|
|
int merged = 0;
|
|
int error;
|
|
int newetype;
|
|
|
|
UVMHIST_FUNC("uvm_map_enter");
|
|
UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, "(map=0x%x, start=0x%x, size=%d, flags=0x%x)",
|
|
map, start, size, flags);
|
|
UVMHIST_LOG(maphist, " uobj/offset 0x%x/%d", uobj, uoffset,0,0);
|
|
|
|
KASSERT(map->hint == prev_entry); /* bimerge case assumes this */
|
|
|
|
if (flags & UVM_FLAG_QUANTUM) {
|
|
KASSERT(new_entry);
|
|
KASSERT(new_entry->flags & UVM_MAP_QUANTUM);
|
|
}
|
|
|
|
if (uobj)
|
|
newetype = UVM_ET_OBJ;
|
|
else
|
|
newetype = 0;
|
|
|
|
if (flags & UVM_FLAG_COPYONW) {
|
|
newetype |= UVM_ET_COPYONWRITE;
|
|
if ((flags & UVM_FLAG_OVERLAY) == 0)
|
|
newetype |= UVM_ET_NEEDSCOPY;
|
|
}
|
|
|
|
/*
|
|
* try and insert in map by extending previous entry, if possible.
|
|
* XXX: we don't try and pull back the next entry. might be useful
|
|
* for a stack, but we are currently allocating our stack in advance.
|
|
*/
|
|
|
|
if (flags & UVM_FLAG_NOMERGE)
|
|
goto nomerge;
|
|
|
|
if (prev_entry->end == start &&
|
|
prev_entry != &map->header &&
|
|
UVM_ET_ISCOMPATIBLE(prev_entry, newetype, uobj, meflagval,
|
|
prot, maxprot, inherit, advice, 0)) {
|
|
|
|
if (uobj && prev_entry->offset +
|
|
(prev_entry->end - prev_entry->start) != uoffset)
|
|
goto forwardmerge;
|
|
|
|
/*
|
|
* can't extend a shared amap. note: no need to lock amap to
|
|
* look at refs since we don't care about its exact value.
|
|
* if it is one (i.e. we have only reference) it will stay there
|
|
*/
|
|
|
|
if (prev_entry->aref.ar_amap &&
|
|
amap_refs(prev_entry->aref.ar_amap) != 1) {
|
|
goto forwardmerge;
|
|
}
|
|
|
|
if (prev_entry->aref.ar_amap) {
|
|
error = amap_extend(prev_entry, size,
|
|
amapwaitflag | AMAP_EXTEND_FORWARDS);
|
|
if (error)
|
|
goto nomerge;
|
|
}
|
|
|
|
if (kmap)
|
|
UVMMAP_EVCNT_INCR(kbackmerge);
|
|
else
|
|
UVMMAP_EVCNT_INCR(ubackmerge);
|
|
UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0);
|
|
|
|
/*
|
|
* drop our reference to uobj since we are extending a reference
|
|
* that we already have (the ref count can not drop to zero).
|
|
*/
|
|
|
|
if (uobj && uobj->pgops->pgo_detach)
|
|
uobj->pgops->pgo_detach(uobj);
|
|
|
|
prev_entry->end += size;
|
|
uvm_rb_fixup(map, prev_entry);
|
|
|
|
uvm_map_check(map, "map backmerged");
|
|
|
|
UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0);
|
|
merged++;
|
|
}
|
|
|
|
forwardmerge:
|
|
if (prev_entry->next->start == (start + size) &&
|
|
prev_entry->next != &map->header &&
|
|
UVM_ET_ISCOMPATIBLE(prev_entry->next, newetype, uobj, meflagval,
|
|
prot, maxprot, inherit, advice, 0)) {
|
|
|
|
if (uobj && prev_entry->next->offset != uoffset + size)
|
|
goto nomerge;
|
|
|
|
/*
|
|
* can't extend a shared amap. note: no need to lock amap to
|
|
* look at refs since we don't care about its exact value.
|
|
* if it is one (i.e. we have only reference) it will stay there.
|
|
*
|
|
* note that we also can't merge two amaps, so if we
|
|
* merged with the previous entry which has an amap,
|
|
* and the next entry also has an amap, we give up.
|
|
*
|
|
* Interesting cases:
|
|
* amap, new, amap -> give up second merge (single fwd extend)
|
|
* amap, new, none -> double forward extend (extend again here)
|
|
* none, new, amap -> double backward extend (done here)
|
|
* uobj, new, amap -> single backward extend (done here)
|
|
*
|
|
* XXX should we attempt to deal with someone refilling
|
|
* the deallocated region between two entries that are
|
|
* backed by the same amap (ie, arefs is 2, "prev" and
|
|
* "next" refer to it, and adding this allocation will
|
|
* close the hole, thus restoring arefs to 1 and
|
|
* deallocating the "next" vm_map_entry)? -- @@@
|
|
*/
|
|
|
|
if (prev_entry->next->aref.ar_amap &&
|
|
(amap_refs(prev_entry->next->aref.ar_amap) != 1 ||
|
|
(merged && prev_entry->aref.ar_amap))) {
|
|
goto nomerge;
|
|
}
|
|
|
|
if (merged) {
|
|
/*
|
|
* Try to extend the amap of the previous entry to
|
|
* cover the next entry as well. If it doesn't work
|
|
* just skip on, don't actually give up, since we've
|
|
* already completed the back merge.
|
|
*/
|
|
if (prev_entry->aref.ar_amap) {
|
|
if (amap_extend(prev_entry,
|
|
prev_entry->next->end -
|
|
prev_entry->next->start,
|
|
amapwaitflag | AMAP_EXTEND_FORWARDS))
|
|
goto nomerge;
|
|
}
|
|
|
|
/*
|
|
* Try to extend the amap of the *next* entry
|
|
* back to cover the new allocation *and* the
|
|
* previous entry as well (the previous merge
|
|
* didn't have an amap already otherwise we
|
|
* wouldn't be checking here for an amap). If
|
|
* it doesn't work just skip on, again, don't
|
|
* actually give up, since we've already
|
|
* completed the back merge.
|
|
*/
|
|
else if (prev_entry->next->aref.ar_amap) {
|
|
if (amap_extend(prev_entry->next,
|
|
prev_entry->end -
|
|
prev_entry->start,
|
|
amapwaitflag | AMAP_EXTEND_BACKWARDS))
|
|
goto nomerge;
|
|
}
|
|
} else {
|
|
/*
|
|
* Pull the next entry's amap backwards to cover this
|
|
* new allocation.
|
|
*/
|
|
if (prev_entry->next->aref.ar_amap) {
|
|
error = amap_extend(prev_entry->next, size,
|
|
amapwaitflag | AMAP_EXTEND_BACKWARDS);
|
|
if (error)
|
|
goto nomerge;
|
|
}
|
|
}
|
|
|
|
if (merged) {
|
|
if (kmap) {
|
|
UVMMAP_EVCNT_DECR(kbackmerge);
|
|
UVMMAP_EVCNT_INCR(kbimerge);
|
|
} else {
|
|
UVMMAP_EVCNT_DECR(ubackmerge);
|
|
UVMMAP_EVCNT_INCR(ubimerge);
|
|
}
|
|
} else {
|
|
if (kmap)
|
|
UVMMAP_EVCNT_INCR(kforwmerge);
|
|
else
|
|
UVMMAP_EVCNT_INCR(uforwmerge);
|
|
}
|
|
UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0);
|
|
|
|
/*
|
|
* drop our reference to uobj since we are extending a reference
|
|
* that we already have (the ref count can not drop to zero).
|
|
* (if merged, we've already detached)
|
|
*/
|
|
if (uobj && uobj->pgops->pgo_detach && !merged)
|
|
uobj->pgops->pgo_detach(uobj);
|
|
|
|
if (merged) {
|
|
dead = prev_entry->next;
|
|
prev_entry->end = dead->end;
|
|
uvm_map_entry_unlink(map, dead);
|
|
if (dead->aref.ar_amap != NULL) {
|
|
prev_entry->aref = dead->aref;
|
|
dead->aref.ar_amap = NULL;
|
|
}
|
|
} else {
|
|
prev_entry->next->start -= size;
|
|
if (prev_entry != &map->header)
|
|
uvm_rb_fixup(map, prev_entry);
|
|
if (uobj)
|
|
prev_entry->next->offset = uoffset;
|
|
}
|
|
|
|
uvm_map_check(map, "map forwardmerged");
|
|
|
|
UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0);
|
|
merged++;
|
|
}
|
|
|
|
nomerge:
|
|
if (!merged) {
|
|
UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0);
|
|
if (kmap)
|
|
UVMMAP_EVCNT_INCR(knomerge);
|
|
else
|
|
UVMMAP_EVCNT_INCR(unomerge);
|
|
|
|
/*
|
|
* allocate new entry and link it in.
|
|
*/
|
|
|
|
if (new_entry == NULL) {
|
|
new_entry = uvm_mapent_alloc(map,
|
|
(flags & UVM_FLAG_NOWAIT));
|
|
if (__predict_false(new_entry == NULL)) {
|
|
error = ENOMEM;
|
|
goto done;
|
|
}
|
|
}
|
|
new_entry->start = start;
|
|
new_entry->end = new_entry->start + size;
|
|
new_entry->object.uvm_obj = uobj;
|
|
new_entry->offset = uoffset;
|
|
|
|
new_entry->etype = newetype;
|
|
|
|
if (flags & UVM_FLAG_NOMERGE) {
|
|
new_entry->flags |= UVM_MAP_NOMERGE;
|
|
}
|
|
|
|
new_entry->protection = prot;
|
|
new_entry->max_protection = maxprot;
|
|
new_entry->inheritance = inherit;
|
|
new_entry->wired_count = 0;
|
|
new_entry->advice = advice;
|
|
if (flags & UVM_FLAG_OVERLAY) {
|
|
|
|
/*
|
|
* to_add: for BSS we overallocate a little since we
|
|
* are likely to extend
|
|
*/
|
|
|
|
vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ?
|
|
UVM_AMAP_CHUNK << PAGE_SHIFT : 0;
|
|
struct vm_amap *amap = amap_alloc(size, to_add,
|
|
(flags & UVM_FLAG_NOWAIT));
|
|
if (__predict_false(amap == NULL)) {
|
|
error = ENOMEM;
|
|
goto done;
|
|
}
|
|
new_entry->aref.ar_pageoff = 0;
|
|
new_entry->aref.ar_amap = amap;
|
|
} else {
|
|
new_entry->aref.ar_pageoff = 0;
|
|
new_entry->aref.ar_amap = NULL;
|
|
}
|
|
uvm_map_entry_link(map, prev_entry, new_entry);
|
|
|
|
/*
|
|
* Update the free space hint
|
|
*/
|
|
|
|
if ((map->first_free == prev_entry) &&
|
|
(prev_entry->end >= new_entry->start))
|
|
map->first_free = new_entry;
|
|
|
|
new_entry = NULL;
|
|
}
|
|
|
|
map->size += size;
|
|
|
|
UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0);
|
|
|
|
error = 0;
|
|
done:
|
|
vm_map_unlock(map);
|
|
if (new_entry) {
|
|
if (error == 0) {
|
|
KDASSERT(merged);
|
|
uvm_mapent_free_merged(map, new_entry);
|
|
} else {
|
|
uvm_mapent_free(new_entry);
|
|
}
|
|
}
|
|
if (dead) {
|
|
KDASSERT(merged);
|
|
uvm_mapent_free_merged(map, dead);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_lookup_entry: find map entry at or before an address
|
|
*
|
|
* => map must at least be read-locked by caller
|
|
* => entry is returned in "entry"
|
|
* => return value is true if address is in the returned entry
|
|
*/
|
|
|
|
bool
|
|
uvm_map_lookup_entry(struct vm_map *map, vaddr_t address,
|
|
struct vm_map_entry **entry /* OUT */)
|
|
{
|
|
struct vm_map_entry *cur;
|
|
bool use_tree = false;
|
|
UVMHIST_FUNC("uvm_map_lookup_entry");
|
|
UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(map=0x%x,addr=0x%x,ent=0x%x)",
|
|
map, address, entry, 0);
|
|
|
|
/*
|
|
* start looking either from the head of the
|
|
* list, or from the hint.
|
|
*/
|
|
|
|
mutex_enter(&map->hint_lock);
|
|
cur = map->hint;
|
|
mutex_exit(&map->hint_lock);
|
|
|
|
if (cur == &map->header)
|
|
cur = cur->next;
|
|
|
|
UVMMAP_EVCNT_INCR(mlk_call);
|
|
if (address >= cur->start) {
|
|
|
|
/*
|
|
* go from hint to end of list.
|
|
*
|
|
* but first, make a quick check to see if
|
|
* we are already looking at the entry we
|
|
* want (which is usually the case).
|
|
* note also that we don't need to save the hint
|
|
* here... it is the same hint (unless we are
|
|
* at the header, in which case the hint didn't
|
|
* buy us anything anyway).
|
|
*/
|
|
|
|
if (cur != &map->header && cur->end > address) {
|
|
UVMMAP_EVCNT_INCR(mlk_hint);
|
|
*entry = cur;
|
|
UVMHIST_LOG(maphist,"<- got it via hint (0x%x)",
|
|
cur, 0, 0, 0);
|
|
uvm_mapent_check(*entry);
|
|
return (true);
|
|
}
|
|
|
|
if (map->nentries > 30)
|
|
use_tree = true;
|
|
} else {
|
|
|
|
/*
|
|
* invalid hint. use tree.
|
|
*/
|
|
use_tree = true;
|
|
}
|
|
|
|
uvm_map_check(map, __func__);
|
|
|
|
if (use_tree) {
|
|
struct vm_map_entry *prev = &map->header;
|
|
cur = RB_ROOT(&map->rbhead);
|
|
|
|
/*
|
|
* Simple lookup in the tree. Happens when the hint is
|
|
* invalid, or nentries reach a threshold.
|
|
*/
|
|
while (cur) {
|
|
if (address >= cur->start) {
|
|
if (address < cur->end) {
|
|
*entry = cur;
|
|
goto got;
|
|
}
|
|
prev = cur;
|
|
cur = RB_RIGHT(cur, rb_entry);
|
|
} else
|
|
cur = RB_LEFT(cur, rb_entry);
|
|
}
|
|
*entry = prev;
|
|
goto failed;
|
|
}
|
|
|
|
/*
|
|
* search linearly
|
|
*/
|
|
|
|
while (cur != &map->header) {
|
|
if (cur->end > address) {
|
|
if (address >= cur->start) {
|
|
/*
|
|
* save this lookup for future
|
|
* hints, and return
|
|
*/
|
|
|
|
*entry = cur;
|
|
got:
|
|
SAVE_HINT(map, map->hint, *entry);
|
|
UVMHIST_LOG(maphist,"<- search got it (0x%x)",
|
|
cur, 0, 0, 0);
|
|
KDASSERT((*entry)->start <= address);
|
|
KDASSERT(address < (*entry)->end);
|
|
uvm_mapent_check(*entry);
|
|
return (true);
|
|
}
|
|
break;
|
|
}
|
|
cur = cur->next;
|
|
}
|
|
*entry = cur->prev;
|
|
failed:
|
|
SAVE_HINT(map, map->hint, *entry);
|
|
UVMHIST_LOG(maphist,"<- failed!",0,0,0,0);
|
|
KDASSERT((*entry) == &map->header || (*entry)->end <= address);
|
|
KDASSERT((*entry)->next == &map->header ||
|
|
address < (*entry)->next->start);
|
|
return (false);
|
|
}
|
|
|
|
/*
|
|
* See if the range between start and start + length fits in the gap
|
|
* entry->next->start and entry->end. Returns 1 if fits, 0 if doesn't
|
|
* fit, and -1 address wraps around.
|
|
*/
|
|
static int
|
|
uvm_map_space_avail(vaddr_t *start, vsize_t length, voff_t uoffset,
|
|
vsize_t align, int topdown, struct vm_map_entry *entry)
|
|
{
|
|
vaddr_t end;
|
|
|
|
#ifdef PMAP_PREFER
|
|
/*
|
|
* push start address forward as needed to avoid VAC alias problems.
|
|
* we only do this if a valid offset is specified.
|
|
*/
|
|
|
|
if (uoffset != UVM_UNKNOWN_OFFSET)
|
|
PMAP_PREFER(uoffset, start, length, topdown);
|
|
#endif
|
|
if (align != 0) {
|
|
if ((*start & (align - 1)) != 0) {
|
|
if (topdown)
|
|
*start &= ~(align - 1);
|
|
else
|
|
*start = roundup(*start, align);
|
|
}
|
|
/*
|
|
* XXX Should we PMAP_PREFER() here again?
|
|
* eh...i think we're okay
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* Find the end of the proposed new region. Be sure we didn't
|
|
* wrap around the address; if so, we lose. Otherwise, if the
|
|
* proposed new region fits before the next entry, we win.
|
|
*/
|
|
|
|
end = *start + length;
|
|
if (end < *start)
|
|
return (-1);
|
|
|
|
if (entry->next->start >= end && *start >= entry->end)
|
|
return (1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* uvm_map_findspace: find "length" sized space in "map".
|
|
*
|
|
* => "hint" is a hint about where we want it, unless UVM_FLAG_FIXED is
|
|
* set in "flags" (in which case we insist on using "hint").
|
|
* => "result" is VA returned
|
|
* => uobj/uoffset are to be used to handle VAC alignment, if required
|
|
* => if "align" is non-zero, we attempt to align to that value.
|
|
* => caller must at least have read-locked map
|
|
* => returns NULL on failure, or pointer to prev. map entry if success
|
|
* => note this is a cross between the old vm_map_findspace and vm_map_find
|
|
*/
|
|
|
|
struct vm_map_entry *
|
|
uvm_map_findspace(struct vm_map *map, vaddr_t hint, vsize_t length,
|
|
vaddr_t *result /* OUT */, struct uvm_object *uobj, voff_t uoffset,
|
|
vsize_t align, int flags)
|
|
{
|
|
struct vm_map_entry *entry;
|
|
struct vm_map_entry *child, *prev, *tmp;
|
|
vaddr_t orig_hint;
|
|
const int topdown = map->flags & VM_MAP_TOPDOWN;
|
|
UVMHIST_FUNC("uvm_map_findspace");
|
|
UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, "(map=0x%x, hint=0x%x, len=%d, flags=0x%x)",
|
|
map, hint, length, flags);
|
|
KASSERT((align & (align - 1)) == 0);
|
|
KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0);
|
|
|
|
uvm_map_check(map, "map_findspace entry");
|
|
|
|
/*
|
|
* remember the original hint. if we are aligning, then we
|
|
* may have to try again with no alignment constraint if
|
|
* we fail the first time.
|
|
*/
|
|
|
|
orig_hint = hint;
|
|
if (hint < vm_map_min(map)) { /* check ranges ... */
|
|
if (flags & UVM_FLAG_FIXED) {
|
|
UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0);
|
|
return (NULL);
|
|
}
|
|
hint = vm_map_min(map);
|
|
}
|
|
if (hint > vm_map_max(map)) {
|
|
UVMHIST_LOG(maphist,"<- VA 0x%x > range [0x%x->0x%x]",
|
|
hint, vm_map_min(map), vm_map_max(map), 0);
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Look for the first possible address; if there's already
|
|
* something at this address, we have to start after it.
|
|
*/
|
|
|
|
/*
|
|
* @@@: there are four, no, eight cases to consider.
|
|
*
|
|
* 0: found, fixed, bottom up -> fail
|
|
* 1: found, fixed, top down -> fail
|
|
* 2: found, not fixed, bottom up -> start after entry->end,
|
|
* loop up
|
|
* 3: found, not fixed, top down -> start before entry->start,
|
|
* loop down
|
|
* 4: not found, fixed, bottom up -> check entry->next->start, fail
|
|
* 5: not found, fixed, top down -> check entry->next->start, fail
|
|
* 6: not found, not fixed, bottom up -> check entry->next->start,
|
|
* loop up
|
|
* 7: not found, not fixed, top down -> check entry->next->start,
|
|
* loop down
|
|
*
|
|
* as you can see, it reduces to roughly five cases, and that
|
|
* adding top down mapping only adds one unique case (without
|
|
* it, there would be four cases).
|
|
*/
|
|
|
|
if ((flags & UVM_FLAG_FIXED) == 0 && hint == vm_map_min(map)) {
|
|
entry = map->first_free;
|
|
} else {
|
|
if (uvm_map_lookup_entry(map, hint, &entry)) {
|
|
/* "hint" address already in use ... */
|
|
if (flags & UVM_FLAG_FIXED) {
|
|
UVMHIST_LOG(maphist, "<- fixed & VA in use",
|
|
0, 0, 0, 0);
|
|
return (NULL);
|
|
}
|
|
if (topdown)
|
|
/* Start from lower gap. */
|
|
entry = entry->prev;
|
|
} else if (flags & UVM_FLAG_FIXED) {
|
|
if (entry->next->start >= hint + length &&
|
|
hint + length > hint)
|
|
goto found;
|
|
|
|
/* "hint" address is gap but too small */
|
|
UVMHIST_LOG(maphist, "<- fixed mapping failed",
|
|
0, 0, 0, 0);
|
|
return (NULL); /* only one shot at it ... */
|
|
} else {
|
|
/*
|
|
* See if given hint fits in this gap.
|
|
*/
|
|
switch (uvm_map_space_avail(&hint, length,
|
|
uoffset, align, topdown, entry)) {
|
|
case 1:
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
|
|
if (topdown) {
|
|
/*
|
|
* Still there is a chance to fit
|
|
* if hint > entry->end.
|
|
*/
|
|
} else {
|
|
/* Start from higher gap. */
|
|
entry = entry->next;
|
|
if (entry == &map->header)
|
|
goto notfound;
|
|
goto nextgap;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note that all UVM_FLAGS_FIXED case is already handled.
|
|
*/
|
|
KDASSERT((flags & UVM_FLAG_FIXED) == 0);
|
|
|
|
/* Try to find the space in the red-black tree */
|
|
|
|
/* Check slot before any entry */
|
|
hint = topdown ? entry->next->start - length : entry->end;
|
|
switch (uvm_map_space_avail(&hint, length, uoffset, align,
|
|
topdown, entry)) {
|
|
case 1:
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
|
|
nextgap:
|
|
KDASSERT((flags & UVM_FLAG_FIXED) == 0);
|
|
/* If there is not enough space in the whole tree, we fail */
|
|
tmp = RB_ROOT(&map->rbhead);
|
|
if (tmp == NULL || tmp->space < length)
|
|
goto notfound;
|
|
|
|
prev = NULL; /* previous candidate */
|
|
|
|
/* Find an entry close to hint that has enough space */
|
|
for (; tmp;) {
|
|
KASSERT(tmp->next->start == tmp->end + tmp->ownspace);
|
|
if (topdown) {
|
|
if (tmp->next->start < hint + length &&
|
|
(prev == NULL || tmp->end > prev->end)) {
|
|
if (tmp->ownspace >= length)
|
|
prev = tmp;
|
|
else if ((child = RB_LEFT(tmp, rb_entry))
|
|
!= NULL && child->space >= length)
|
|
prev = tmp;
|
|
}
|
|
} else {
|
|
if (tmp->end >= hint &&
|
|
(prev == NULL || tmp->end < prev->end)) {
|
|
if (tmp->ownspace >= length)
|
|
prev = tmp;
|
|
else if ((child = RB_RIGHT(tmp, rb_entry))
|
|
!= NULL && child->space >= length)
|
|
prev = tmp;
|
|
}
|
|
}
|
|
if (tmp->next->start < hint + length)
|
|
child = RB_RIGHT(tmp, rb_entry);
|
|
else if (tmp->end > hint)
|
|
child = RB_LEFT(tmp, rb_entry);
|
|
else {
|
|
if (tmp->ownspace >= length)
|
|
break;
|
|
if (topdown)
|
|
child = RB_LEFT(tmp, rb_entry);
|
|
else
|
|
child = RB_RIGHT(tmp, rb_entry);
|
|
}
|
|
if (child == NULL || child->space < length)
|
|
break;
|
|
tmp = child;
|
|
}
|
|
|
|
if (tmp != NULL && tmp->start < hint && hint < tmp->next->start) {
|
|
/*
|
|
* Check if the entry that we found satifies the
|
|
* space requirement
|
|
*/
|
|
if (topdown) {
|
|
if (hint > tmp->next->start - length)
|
|
hint = tmp->next->start - length;
|
|
} else {
|
|
if (hint < tmp->end)
|
|
hint = tmp->end;
|
|
}
|
|
switch (uvm_map_space_avail(&hint, length, uoffset, align,
|
|
topdown, tmp)) {
|
|
case 1:
|
|
entry = tmp;
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
if (tmp->ownspace >= length)
|
|
goto listsearch;
|
|
}
|
|
if (prev == NULL)
|
|
goto notfound;
|
|
|
|
if (topdown) {
|
|
KASSERT(orig_hint >= prev->next->start - length ||
|
|
prev->next->start - length > prev->next->start);
|
|
hint = prev->next->start - length;
|
|
} else {
|
|
KASSERT(orig_hint <= prev->end);
|
|
hint = prev->end;
|
|
}
|
|
switch (uvm_map_space_avail(&hint, length, uoffset, align,
|
|
topdown, prev)) {
|
|
case 1:
|
|
entry = prev;
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
if (prev->ownspace >= length)
|
|
goto listsearch;
|
|
|
|
if (topdown)
|
|
tmp = RB_LEFT(prev, rb_entry);
|
|
else
|
|
tmp = RB_RIGHT(prev, rb_entry);
|
|
for (;;) {
|
|
KASSERT(tmp && tmp->space >= length);
|
|
if (topdown)
|
|
child = RB_RIGHT(tmp, rb_entry);
|
|
else
|
|
child = RB_LEFT(tmp, rb_entry);
|
|
if (child && child->space >= length) {
|
|
tmp = child;
|
|
continue;
|
|
}
|
|
if (tmp->ownspace >= length)
|
|
break;
|
|
if (topdown)
|
|
tmp = RB_LEFT(tmp, rb_entry);
|
|
else
|
|
tmp = RB_RIGHT(tmp, rb_entry);
|
|
}
|
|
|
|
if (topdown) {
|
|
KASSERT(orig_hint >= tmp->next->start - length ||
|
|
tmp->next->start - length > tmp->next->start);
|
|
hint = tmp->next->start - length;
|
|
} else {
|
|
KASSERT(orig_hint <= tmp->end);
|
|
hint = tmp->end;
|
|
}
|
|
switch (uvm_map_space_avail(&hint, length, uoffset, align,
|
|
topdown, tmp)) {
|
|
case 1:
|
|
entry = tmp;
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
|
|
/*
|
|
* The tree fails to find an entry because of offset or alignment
|
|
* restrictions. Search the list instead.
|
|
*/
|
|
listsearch:
|
|
/*
|
|
* Look through the rest of the map, trying to fit a new region in
|
|
* the gap between existing regions, or after the very last region.
|
|
* note: entry->end = base VA of current gap,
|
|
* entry->next->start = VA of end of current gap
|
|
*/
|
|
|
|
for (;;) {
|
|
/* Update hint for current gap. */
|
|
hint = topdown ? entry->next->start - length : entry->end;
|
|
|
|
/* See if it fits. */
|
|
switch (uvm_map_space_avail(&hint, length, uoffset, align,
|
|
topdown, entry)) {
|
|
case 1:
|
|
goto found;
|
|
case -1:
|
|
goto wraparound;
|
|
}
|
|
|
|
/* Advance to next/previous gap */
|
|
if (topdown) {
|
|
if (entry == &map->header) {
|
|
UVMHIST_LOG(maphist, "<- failed (off start)",
|
|
0,0,0,0);
|
|
goto notfound;
|
|
}
|
|
entry = entry->prev;
|
|
} else {
|
|
entry = entry->next;
|
|
if (entry == &map->header) {
|
|
UVMHIST_LOG(maphist, "<- failed (off end)",
|
|
0,0,0,0);
|
|
goto notfound;
|
|
}
|
|
}
|
|
}
|
|
|
|
found:
|
|
SAVE_HINT(map, map->hint, entry);
|
|
*result = hint;
|
|
UVMHIST_LOG(maphist,"<- got it! (result=0x%x)", hint, 0,0,0);
|
|
KASSERT( topdown || hint >= orig_hint);
|
|
KASSERT(!topdown || hint <= orig_hint);
|
|
KASSERT(entry->end <= hint);
|
|
KASSERT(hint + length <= entry->next->start);
|
|
return (entry);
|
|
|
|
wraparound:
|
|
UVMHIST_LOG(maphist, "<- failed (wrap around)", 0,0,0,0);
|
|
|
|
return (NULL);
|
|
|
|
notfound:
|
|
UVMHIST_LOG(maphist, "<- failed (notfound)", 0,0,0,0);
|
|
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* U N M A P - m a i n h e l p e r f u n c t i o n s
|
|
*/
|
|
|
|
/*
|
|
* uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop")
|
|
*
|
|
* => caller must check alignment and size
|
|
* => map must be locked by caller
|
|
* => we return a list of map entries that we've remove from the map
|
|
* in "entry_list"
|
|
*/
|
|
|
|
void
|
|
uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
struct vm_map_entry **entry_list /* OUT */,
|
|
struct uvm_mapent_reservation *umr, int flags)
|
|
{
|
|
struct vm_map_entry *entry, *first_entry, *next;
|
|
vaddr_t len;
|
|
UVMHIST_FUNC("uvm_unmap_remove"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(map=0x%x, start=0x%x, end=0x%x)",
|
|
map, start, end, 0);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
|
|
uvm_map_check(map, "unmap_remove entry");
|
|
|
|
/*
|
|
* find first entry
|
|
*/
|
|
|
|
if (uvm_map_lookup_entry(map, start, &first_entry) == true) {
|
|
/* clip and go... */
|
|
entry = first_entry;
|
|
UVM_MAP_CLIP_START(map, entry, start, umr);
|
|
/* critical! prevents stale hint */
|
|
SAVE_HINT(map, entry, entry->prev);
|
|
} else {
|
|
entry = first_entry->next;
|
|
}
|
|
|
|
/*
|
|
* Save the free space hint
|
|
*/
|
|
|
|
if (map->first_free != &map->header && map->first_free->start >= start)
|
|
map->first_free = entry->prev;
|
|
|
|
/*
|
|
* note: we now re-use first_entry for a different task. we remove
|
|
* a number of map entries from the map and save them in a linked
|
|
* list headed by "first_entry". once we remove them from the map
|
|
* the caller should unlock the map and drop the references to the
|
|
* backing objects [c.f. uvm_unmap_detach]. the object is to
|
|
* separate unmapping from reference dropping. why?
|
|
* [1] the map has to be locked for unmapping
|
|
* [2] the map need not be locked for reference dropping
|
|
* [3] dropping references may trigger pager I/O, and if we hit
|
|
* a pager that does synchronous I/O we may have to wait for it.
|
|
* [4] we would like all waiting for I/O to occur with maps unlocked
|
|
* so that we don't block other threads.
|
|
*/
|
|
|
|
first_entry = NULL;
|
|
*entry_list = NULL;
|
|
|
|
/*
|
|
* break up the area into map entry sized regions and unmap. note
|
|
* that all mappings have to be removed before we can even consider
|
|
* dropping references to amaps or VM objects (otherwise we could end
|
|
* up with a mapping to a page on the free list which would be very bad)
|
|
*/
|
|
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
KASSERT((entry->flags & UVM_MAP_FIRST) == 0);
|
|
|
|
UVM_MAP_CLIP_END(map, entry, end, umr);
|
|
next = entry->next;
|
|
len = entry->end - entry->start;
|
|
|
|
/*
|
|
* unwire before removing addresses from the pmap; otherwise
|
|
* unwiring will put the entries back into the pmap (XXX).
|
|
*/
|
|
|
|
if (VM_MAPENT_ISWIRED(entry)) {
|
|
uvm_map_entry_unwire(map, entry);
|
|
}
|
|
if (flags & UVM_FLAG_VAONLY) {
|
|
|
|
/* nothing */
|
|
|
|
} else if ((map->flags & VM_MAP_PAGEABLE) == 0) {
|
|
|
|
/*
|
|
* if the map is non-pageable, any pages mapped there
|
|
* must be wired and entered with pmap_kenter_pa(),
|
|
* and we should free any such pages immediately.
|
|
* this is mostly used for kmem_map and mb_map.
|
|
*/
|
|
|
|
if ((entry->flags & UVM_MAP_KMAPENT) == 0) {
|
|
uvm_km_pgremove_intrsafe(entry->start,
|
|
entry->end);
|
|
pmap_kremove(entry->start, len);
|
|
}
|
|
} else if (UVM_ET_ISOBJ(entry) &&
|
|
UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) {
|
|
KASSERT(vm_map_pmap(map) == pmap_kernel());
|
|
|
|
/*
|
|
* note: kernel object mappings are currently used in
|
|
* two ways:
|
|
* [1] "normal" mappings of pages in the kernel object
|
|
* [2] uvm_km_valloc'd allocations in which we
|
|
* pmap_enter in some non-kernel-object page
|
|
* (e.g. vmapbuf).
|
|
*
|
|
* for case [1], we need to remove the mapping from
|
|
* the pmap and then remove the page from the kernel
|
|
* object (because, once pages in a kernel object are
|
|
* unmapped they are no longer needed, unlike, say,
|
|
* a vnode where you might want the data to persist
|
|
* until flushed out of a queue).
|
|
*
|
|
* for case [2], we need to remove the mapping from
|
|
* the pmap. there shouldn't be any pages at the
|
|
* specified offset in the kernel object [but it
|
|
* doesn't hurt to call uvm_km_pgremove just to be
|
|
* safe?]
|
|
*
|
|
* uvm_km_pgremove currently does the following:
|
|
* for pages in the kernel object in range:
|
|
* - drops the swap slot
|
|
* - uvm_pagefree the page
|
|
*/
|
|
|
|
/*
|
|
* remove mappings from pmap and drop the pages
|
|
* from the object. offsets are always relative
|
|
* to vm_map_min(kernel_map).
|
|
*/
|
|
|
|
pmap_remove(pmap_kernel(), entry->start,
|
|
entry->start + len);
|
|
uvm_km_pgremove(entry->start, entry->end);
|
|
|
|
/*
|
|
* null out kernel_object reference, we've just
|
|
* dropped it
|
|
*/
|
|
|
|
entry->etype &= ~UVM_ET_OBJ;
|
|
entry->object.uvm_obj = NULL;
|
|
} else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) {
|
|
|
|
/*
|
|
* remove mappings the standard way.
|
|
*/
|
|
|
|
pmap_remove(map->pmap, entry->start, entry->end);
|
|
}
|
|
|
|
#if defined(DEBUG)
|
|
if ((entry->flags & UVM_MAP_KMAPENT) == 0) {
|
|
|
|
/*
|
|
* check if there's remaining mapping,
|
|
* which is a bug in caller.
|
|
*/
|
|
|
|
vaddr_t va;
|
|
for (va = entry->start; va < entry->end;
|
|
va += PAGE_SIZE) {
|
|
if (pmap_extract(vm_map_pmap(map), va, NULL)) {
|
|
panic("uvm_unmap_remove: has mapping");
|
|
}
|
|
}
|
|
|
|
if (VM_MAP_IS_KERNEL(map)) {
|
|
uvm_km_check_empty(entry->start, entry->end,
|
|
(map->flags & VM_MAP_INTRSAFE) != 0);
|
|
}
|
|
}
|
|
#endif /* defined(DEBUG) */
|
|
|
|
/*
|
|
* remove entry from map and put it on our list of entries
|
|
* that we've nuked. then go to next entry.
|
|
*/
|
|
|
|
UVMHIST_LOG(maphist, " removed map entry 0x%x", entry, 0, 0,0);
|
|
|
|
/* critical! prevents stale hint */
|
|
SAVE_HINT(map, entry, entry->prev);
|
|
|
|
uvm_map_entry_unlink(map, entry);
|
|
KASSERT(map->size >= len);
|
|
map->size -= len;
|
|
entry->prev = NULL;
|
|
entry->next = first_entry;
|
|
first_entry = entry;
|
|
entry = next;
|
|
}
|
|
if ((map->flags & VM_MAP_DYING) == 0) {
|
|
pmap_update(vm_map_pmap(map));
|
|
}
|
|
|
|
uvm_map_check(map, "unmap_remove leave");
|
|
|
|
/*
|
|
* now we've cleaned up the map and are ready for the caller to drop
|
|
* references to the mapped objects.
|
|
*/
|
|
|
|
*entry_list = first_entry;
|
|
UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0);
|
|
|
|
if (map->flags & VM_MAP_WANTVA) {
|
|
mutex_enter(&map->misc_lock);
|
|
map->flags &= ~VM_MAP_WANTVA;
|
|
cv_broadcast(&map->cv);
|
|
mutex_exit(&map->misc_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_unmap_detach: drop references in a chain of map entries
|
|
*
|
|
* => we will free the map entries as we traverse the list.
|
|
*/
|
|
|
|
void
|
|
uvm_unmap_detach(struct vm_map_entry *first_entry, int flags)
|
|
{
|
|
struct vm_map_entry *next_entry;
|
|
UVMHIST_FUNC("uvm_unmap_detach"); UVMHIST_CALLED(maphist);
|
|
|
|
while (first_entry) {
|
|
KASSERT(!VM_MAPENT_ISWIRED(first_entry));
|
|
UVMHIST_LOG(maphist,
|
|
" detach 0x%x: amap=0x%x, obj=0x%x, submap?=%d",
|
|
first_entry, first_entry->aref.ar_amap,
|
|
first_entry->object.uvm_obj,
|
|
UVM_ET_ISSUBMAP(first_entry));
|
|
|
|
/*
|
|
* drop reference to amap, if we've got one
|
|
*/
|
|
|
|
if (first_entry->aref.ar_amap)
|
|
uvm_map_unreference_amap(first_entry, flags);
|
|
|
|
/*
|
|
* drop reference to our backing object, if we've got one
|
|
*/
|
|
|
|
KASSERT(!UVM_ET_ISSUBMAP(first_entry));
|
|
if (UVM_ET_ISOBJ(first_entry) &&
|
|
first_entry->object.uvm_obj->pgops->pgo_detach) {
|
|
(*first_entry->object.uvm_obj->pgops->pgo_detach)
|
|
(first_entry->object.uvm_obj);
|
|
}
|
|
next_entry = first_entry->next;
|
|
uvm_mapent_free(first_entry);
|
|
first_entry = next_entry;
|
|
}
|
|
UVMHIST_LOG(maphist, "<- done", 0,0,0,0);
|
|
}
|
|
|
|
/*
|
|
* E X T R A C T I O N F U N C T I O N S
|
|
*/
|
|
|
|
/*
|
|
* uvm_map_reserve: reserve space in a vm_map for future use.
|
|
*
|
|
* => we reserve space in a map by putting a dummy map entry in the
|
|
* map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE)
|
|
* => map should be unlocked (we will write lock it)
|
|
* => we return true if we were able to reserve space
|
|
* => XXXCDC: should be inline?
|
|
*/
|
|
|
|
int
|
|
uvm_map_reserve(struct vm_map *map, vsize_t size,
|
|
vaddr_t offset /* hint for pmap_prefer */,
|
|
vsize_t align /* alignment */,
|
|
vaddr_t *raddr /* IN:hint, OUT: reserved VA */,
|
|
uvm_flag_t flags /* UVM_FLAG_FIXED or 0 */)
|
|
{
|
|
UVMHIST_FUNC("uvm_map_reserve"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x, offset=0x%x,addr=0x%x)",
|
|
map,size,offset,raddr);
|
|
|
|
size = round_page(size);
|
|
|
|
/*
|
|
* reserve some virtual space.
|
|
*/
|
|
|
|
if (uvm_map(map, raddr, size, NULL, offset, align,
|
|
UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE,
|
|
UVM_ADV_RANDOM, UVM_FLAG_NOMERGE|flags)) != 0) {
|
|
UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0);
|
|
return (false);
|
|
}
|
|
|
|
UVMHIST_LOG(maphist, "<- done (*raddr=0x%x)", *raddr,0,0,0);
|
|
return (true);
|
|
}
|
|
|
|
/*
|
|
* uvm_map_replace: replace a reserved (blank) area of memory with
|
|
* real mappings.
|
|
*
|
|
* => caller must WRITE-LOCK the map
|
|
* => we return true if replacement was a success
|
|
* => we expect the newents chain to have nnewents entrys on it and
|
|
* we expect newents->prev to point to the last entry on the list
|
|
* => note newents is allowed to be NULL
|
|
*/
|
|
|
|
int
|
|
uvm_map_replace(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
struct vm_map_entry *newents, int nnewents)
|
|
{
|
|
struct vm_map_entry *oldent, *last;
|
|
|
|
uvm_map_check(map, "map_replace entry");
|
|
|
|
/*
|
|
* first find the blank map entry at the specified address
|
|
*/
|
|
|
|
if (!uvm_map_lookup_entry(map, start, &oldent)) {
|
|
return (false);
|
|
}
|
|
|
|
/*
|
|
* check to make sure we have a proper blank entry
|
|
*/
|
|
|
|
if (end < oldent->end && !VM_MAP_USE_KMAPENT(map)) {
|
|
UVM_MAP_CLIP_END(map, oldent, end, NULL);
|
|
}
|
|
if (oldent->start != start || oldent->end != end ||
|
|
oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) {
|
|
return (false);
|
|
}
|
|
|
|
#ifdef DIAGNOSTIC
|
|
|
|
/*
|
|
* sanity check the newents chain
|
|
*/
|
|
|
|
{
|
|
struct vm_map_entry *tmpent = newents;
|
|
int nent = 0;
|
|
vaddr_t cur = start;
|
|
|
|
while (tmpent) {
|
|
nent++;
|
|
if (tmpent->start < cur)
|
|
panic("uvm_map_replace1");
|
|
if (tmpent->start > tmpent->end || tmpent->end > end) {
|
|
printf("tmpent->start=0x%lx, tmpent->end=0x%lx, end=0x%lx\n",
|
|
tmpent->start, tmpent->end, end);
|
|
panic("uvm_map_replace2");
|
|
}
|
|
cur = tmpent->end;
|
|
if (tmpent->next) {
|
|
if (tmpent->next->prev != tmpent)
|
|
panic("uvm_map_replace3");
|
|
} else {
|
|
if (newents->prev != tmpent)
|
|
panic("uvm_map_replace4");
|
|
}
|
|
tmpent = tmpent->next;
|
|
}
|
|
if (nent != nnewents)
|
|
panic("uvm_map_replace5");
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* map entry is a valid blank! replace it. (this does all the
|
|
* work of map entry link/unlink...).
|
|
*/
|
|
|
|
if (newents) {
|
|
last = newents->prev;
|
|
|
|
/* critical: flush stale hints out of map */
|
|
SAVE_HINT(map, map->hint, newents);
|
|
if (map->first_free == oldent)
|
|
map->first_free = last;
|
|
|
|
last->next = oldent->next;
|
|
last->next->prev = last;
|
|
|
|
/* Fix RB tree */
|
|
uvm_rb_remove(map, oldent);
|
|
|
|
newents->prev = oldent->prev;
|
|
newents->prev->next = newents;
|
|
map->nentries = map->nentries + (nnewents - 1);
|
|
|
|
/* Fixup the RB tree */
|
|
{
|
|
int i;
|
|
struct vm_map_entry *tmp;
|
|
|
|
tmp = newents;
|
|
for (i = 0; i < nnewents && tmp; i++) {
|
|
uvm_rb_insert(map, tmp);
|
|
tmp = tmp->next;
|
|
}
|
|
}
|
|
} else {
|
|
/* NULL list of new entries: just remove the old one */
|
|
clear_hints(map, oldent);
|
|
uvm_map_entry_unlink(map, oldent);
|
|
}
|
|
|
|
uvm_map_check(map, "map_replace leave");
|
|
|
|
/*
|
|
* now we can free the old blank entry and return.
|
|
*/
|
|
|
|
uvm_mapent_free(oldent);
|
|
return (true);
|
|
}
|
|
|
|
/*
|
|
* uvm_map_extract: extract a mapping from a map and put it somewhere
|
|
* (maybe removing the old mapping)
|
|
*
|
|
* => maps should be unlocked (we will write lock them)
|
|
* => returns 0 on success, error code otherwise
|
|
* => start must be page aligned
|
|
* => len must be page sized
|
|
* => flags:
|
|
* UVM_EXTRACT_REMOVE: remove mappings from srcmap
|
|
* UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only)
|
|
* UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs
|
|
* UVM_EXTRACT_FIXPROT: set prot to maxprot as we go
|
|
* >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<<
|
|
* >>>NOTE: QREF's must be unmapped via the QREF path, thus should only
|
|
* be used from within the kernel in a kernel level map <<<
|
|
*/
|
|
|
|
int
|
|
uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len,
|
|
struct vm_map *dstmap, vaddr_t *dstaddrp, int flags)
|
|
{
|
|
vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge;
|
|
struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry,
|
|
*deadentry, *oldentry;
|
|
vsize_t elen;
|
|
int nchain, error, copy_ok;
|
|
UVMHIST_FUNC("uvm_map_extract"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(srcmap=0x%x,start=0x%x, len=0x%x", srcmap, start,
|
|
len,0);
|
|
UVMHIST_LOG(maphist," ...,dstmap=0x%x, flags=0x%x)", dstmap,flags,0,0);
|
|
|
|
uvm_map_check(srcmap, "map_extract src enter");
|
|
uvm_map_check(dstmap, "map_extract dst enter");
|
|
|
|
/*
|
|
* step 0: sanity check: start must be on a page boundary, length
|
|
* must be page sized. can't ask for CONTIG/QREF if you asked for
|
|
* REMOVE.
|
|
*/
|
|
|
|
KASSERT((start & PAGE_MASK) == 0 && (len & PAGE_MASK) == 0);
|
|
KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 ||
|
|
(flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0);
|
|
|
|
/*
|
|
* step 1: reserve space in the target map for the extracted area
|
|
*/
|
|
|
|
if ((flags & UVM_EXTRACT_RESERVED) == 0) {
|
|
dstaddr = vm_map_min(dstmap);
|
|
if (!uvm_map_reserve(dstmap, len, start, 0, &dstaddr, 0))
|
|
return (ENOMEM);
|
|
*dstaddrp = dstaddr; /* pass address back to caller */
|
|
UVMHIST_LOG(maphist, " dstaddr=0x%x", dstaddr,0,0,0);
|
|
} else {
|
|
dstaddr = *dstaddrp;
|
|
}
|
|
|
|
/*
|
|
* step 2: setup for the extraction process loop by init'ing the
|
|
* map entry chain, locking src map, and looking up the first useful
|
|
* entry in the map.
|
|
*/
|
|
|
|
end = start + len;
|
|
newend = dstaddr + len;
|
|
chain = endchain = NULL;
|
|
nchain = 0;
|
|
vm_map_lock(srcmap);
|
|
|
|
if (uvm_map_lookup_entry(srcmap, start, &entry)) {
|
|
|
|
/* "start" is within an entry */
|
|
if (flags & UVM_EXTRACT_QREF) {
|
|
|
|
/*
|
|
* for quick references we don't clip the entry, so
|
|
* the entry may map space "before" the starting
|
|
* virtual address... this is the "fudge" factor
|
|
* (which can be non-zero only the first time
|
|
* through the "while" loop in step 3).
|
|
*/
|
|
|
|
fudge = start - entry->start;
|
|
} else {
|
|
|
|
/*
|
|
* normal reference: we clip the map to fit (thus
|
|
* fudge is zero)
|
|
*/
|
|
|
|
UVM_MAP_CLIP_START(srcmap, entry, start, NULL);
|
|
SAVE_HINT(srcmap, srcmap->hint, entry->prev);
|
|
fudge = 0;
|
|
}
|
|
} else {
|
|
|
|
/* "start" is not within an entry ... skip to next entry */
|
|
if (flags & UVM_EXTRACT_CONTIG) {
|
|
error = EINVAL;
|
|
goto bad; /* definite hole here ... */
|
|
}
|
|
|
|
entry = entry->next;
|
|
fudge = 0;
|
|
}
|
|
|
|
/* save values from srcmap for step 6 */
|
|
orig_entry = entry;
|
|
orig_fudge = fudge;
|
|
|
|
/*
|
|
* step 3: now start looping through the map entries, extracting
|
|
* as we go.
|
|
*/
|
|
|
|
while (entry->start < end && entry != &srcmap->header) {
|
|
|
|
/* if we are not doing a quick reference, clip it */
|
|
if ((flags & UVM_EXTRACT_QREF) == 0)
|
|
UVM_MAP_CLIP_END(srcmap, entry, end, NULL);
|
|
|
|
/* clear needs_copy (allow chunking) */
|
|
if (UVM_ET_ISNEEDSCOPY(entry)) {
|
|
amap_copy(srcmap, entry,
|
|
AMAP_COPY_NOWAIT|AMAP_COPY_NOMERGE, start, end);
|
|
if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */
|
|
error = ENOMEM;
|
|
goto bad;
|
|
}
|
|
|
|
/* amap_copy could clip (during chunk)! update fudge */
|
|
if (fudge) {
|
|
fudge = start - entry->start;
|
|
orig_fudge = fudge;
|
|
}
|
|
}
|
|
|
|
/* calculate the offset of this from "start" */
|
|
oldoffset = (entry->start + fudge) - start;
|
|
|
|
/* allocate a new map entry */
|
|
newentry = uvm_mapent_alloc(dstmap, 0);
|
|
if (newentry == NULL) {
|
|
error = ENOMEM;
|
|
goto bad;
|
|
}
|
|
|
|
/* set up new map entry */
|
|
newentry->next = NULL;
|
|
newentry->prev = endchain;
|
|
newentry->start = dstaddr + oldoffset;
|
|
newentry->end =
|
|
newentry->start + (entry->end - (entry->start + fudge));
|
|
if (newentry->end > newend || newentry->end < newentry->start)
|
|
newentry->end = newend;
|
|
newentry->object.uvm_obj = entry->object.uvm_obj;
|
|
if (newentry->object.uvm_obj) {
|
|
if (newentry->object.uvm_obj->pgops->pgo_reference)
|
|
newentry->object.uvm_obj->pgops->
|
|
pgo_reference(newentry->object.uvm_obj);
|
|
newentry->offset = entry->offset + fudge;
|
|
} else {
|
|
newentry->offset = 0;
|
|
}
|
|
newentry->etype = entry->etype;
|
|
newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ?
|
|
entry->max_protection : entry->protection;
|
|
newentry->max_protection = entry->max_protection;
|
|
newentry->inheritance = entry->inheritance;
|
|
newentry->wired_count = 0;
|
|
newentry->aref.ar_amap = entry->aref.ar_amap;
|
|
if (newentry->aref.ar_amap) {
|
|
newentry->aref.ar_pageoff =
|
|
entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT);
|
|
uvm_map_reference_amap(newentry, AMAP_SHARED |
|
|
((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0));
|
|
} else {
|
|
newentry->aref.ar_pageoff = 0;
|
|
}
|
|
newentry->advice = entry->advice;
|
|
|
|
/* now link it on the chain */
|
|
nchain++;
|
|
if (endchain == NULL) {
|
|
chain = endchain = newentry;
|
|
} else {
|
|
endchain->next = newentry;
|
|
endchain = newentry;
|
|
}
|
|
|
|
/* end of 'while' loop! */
|
|
if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end &&
|
|
(entry->next == &srcmap->header ||
|
|
entry->next->start != entry->end)) {
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
entry = entry->next;
|
|
fudge = 0;
|
|
}
|
|
|
|
/*
|
|
* step 4: close off chain (in format expected by uvm_map_replace)
|
|
*/
|
|
|
|
if (chain)
|
|
chain->prev = endchain;
|
|
|
|
/*
|
|
* step 5: attempt to lock the dest map so we can pmap_copy.
|
|
* note usage of copy_ok:
|
|
* 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5)
|
|
* 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7
|
|
*/
|
|
|
|
if (srcmap == dstmap || vm_map_lock_try(dstmap) == true) {
|
|
copy_ok = 1;
|
|
if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain,
|
|
nchain)) {
|
|
if (srcmap != dstmap)
|
|
vm_map_unlock(dstmap);
|
|
error = EIO;
|
|
goto bad;
|
|
}
|
|
} else {
|
|
copy_ok = 0;
|
|
/* replace defered until step 7 */
|
|
}
|
|
|
|
/*
|
|
* step 6: traverse the srcmap a second time to do the following:
|
|
* - if we got a lock on the dstmap do pmap_copy
|
|
* - if UVM_EXTRACT_REMOVE remove the entries
|
|
* we make use of orig_entry and orig_fudge (saved in step 2)
|
|
*/
|
|
|
|
if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) {
|
|
|
|
/* purge possible stale hints from srcmap */
|
|
if (flags & UVM_EXTRACT_REMOVE) {
|
|
SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev);
|
|
if (srcmap->first_free != &srcmap->header &&
|
|
srcmap->first_free->start >= start)
|
|
srcmap->first_free = orig_entry->prev;
|
|
}
|
|
|
|
entry = orig_entry;
|
|
fudge = orig_fudge;
|
|
deadentry = NULL; /* for UVM_EXTRACT_REMOVE */
|
|
|
|
while (entry->start < end && entry != &srcmap->header) {
|
|
if (copy_ok) {
|
|
oldoffset = (entry->start + fudge) - start;
|
|
elen = MIN(end, entry->end) -
|
|
(entry->start + fudge);
|
|
pmap_copy(dstmap->pmap, srcmap->pmap,
|
|
dstaddr + oldoffset, elen,
|
|
entry->start + fudge);
|
|
}
|
|
|
|
/* we advance "entry" in the following if statement */
|
|
if (flags & UVM_EXTRACT_REMOVE) {
|
|
pmap_remove(srcmap->pmap, entry->start,
|
|
entry->end);
|
|
oldentry = entry; /* save entry */
|
|
entry = entry->next; /* advance */
|
|
uvm_map_entry_unlink(srcmap, oldentry);
|
|
/* add to dead list */
|
|
oldentry->next = deadentry;
|
|
deadentry = oldentry;
|
|
} else {
|
|
entry = entry->next; /* advance */
|
|
}
|
|
|
|
/* end of 'while' loop */
|
|
fudge = 0;
|
|
}
|
|
pmap_update(srcmap->pmap);
|
|
|
|
/*
|
|
* unlock dstmap. we will dispose of deadentry in
|
|
* step 7 if needed
|
|
*/
|
|
|
|
if (copy_ok && srcmap != dstmap)
|
|
vm_map_unlock(dstmap);
|
|
|
|
} else {
|
|
deadentry = NULL;
|
|
}
|
|
|
|
/*
|
|
* step 7: we are done with the source map, unlock. if copy_ok
|
|
* is 0 then we have not replaced the dummy mapping in dstmap yet
|
|
* and we need to do so now.
|
|
*/
|
|
|
|
vm_map_unlock(srcmap);
|
|
if ((flags & UVM_EXTRACT_REMOVE) && deadentry)
|
|
uvm_unmap_detach(deadentry, 0); /* dispose of old entries */
|
|
|
|
/* now do the replacement if we didn't do it in step 5 */
|
|
if (copy_ok == 0) {
|
|
vm_map_lock(dstmap);
|
|
error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain,
|
|
nchain);
|
|
vm_map_unlock(dstmap);
|
|
|
|
if (error == false) {
|
|
error = EIO;
|
|
goto bad2;
|
|
}
|
|
}
|
|
|
|
uvm_map_check(srcmap, "map_extract src leave");
|
|
uvm_map_check(dstmap, "map_extract dst leave");
|
|
|
|
return (0);
|
|
|
|
/*
|
|
* bad: failure recovery
|
|
*/
|
|
bad:
|
|
vm_map_unlock(srcmap);
|
|
bad2: /* src already unlocked */
|
|
if (chain)
|
|
uvm_unmap_detach(chain,
|
|
(flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0);
|
|
|
|
uvm_map_check(srcmap, "map_extract src err leave");
|
|
uvm_map_check(dstmap, "map_extract dst err leave");
|
|
|
|
if ((flags & UVM_EXTRACT_RESERVED) == 0) {
|
|
uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/* end of extraction functions */
|
|
|
|
/*
|
|
* uvm_map_submap: punch down part of a map into a submap
|
|
*
|
|
* => only the kernel_map is allowed to be submapped
|
|
* => the purpose of submapping is to break up the locking granularity
|
|
* of a larger map
|
|
* => the range specified must have been mapped previously with a uvm_map()
|
|
* call [with uobj==NULL] to create a blank map entry in the main map.
|
|
* [And it had better still be blank!]
|
|
* => maps which contain submaps should never be copied or forked.
|
|
* => to remove a submap, use uvm_unmap() on the main map
|
|
* and then uvm_map_deallocate() the submap.
|
|
* => main map must be unlocked.
|
|
* => submap must have been init'd and have a zero reference count.
|
|
* [need not be locked as we don't actually reference it]
|
|
*/
|
|
|
|
int
|
|
uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
struct vm_map *submap)
|
|
{
|
|
struct vm_map_entry *entry;
|
|
struct uvm_mapent_reservation umr;
|
|
int error;
|
|
|
|
uvm_mapent_reserve(map, &umr, 2, 0);
|
|
|
|
vm_map_lock(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
|
|
if (uvm_map_lookup_entry(map, start, &entry)) {
|
|
UVM_MAP_CLIP_START(map, entry, start, &umr);
|
|
UVM_MAP_CLIP_END(map, entry, end, &umr); /* to be safe */
|
|
} else {
|
|
entry = NULL;
|
|
}
|
|
|
|
if (entry != NULL &&
|
|
entry->start == start && entry->end == end &&
|
|
entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL &&
|
|
!UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) {
|
|
entry->etype |= UVM_ET_SUBMAP;
|
|
entry->object.sub_map = submap;
|
|
entry->offset = 0;
|
|
uvm_map_reference(submap);
|
|
error = 0;
|
|
} else {
|
|
error = EINVAL;
|
|
}
|
|
vm_map_unlock(map);
|
|
|
|
uvm_mapent_unreserve(map, &umr);
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_setup_kernel: init in-kernel map
|
|
*
|
|
* => map must not be in service yet.
|
|
*/
|
|
|
|
void
|
|
uvm_map_setup_kernel(struct vm_map_kernel *map,
|
|
vaddr_t vmin, vaddr_t vmax, int flags)
|
|
{
|
|
|
|
uvm_map_setup(&map->vmk_map, vmin, vmax, flags);
|
|
callback_head_init(&map->vmk_reclaim_callback, IPL_VM);
|
|
LIST_INIT(&map->vmk_kentry_free);
|
|
map->vmk_merged_entries = NULL;
|
|
}
|
|
|
|
|
|
/*
|
|
* uvm_map_protect: change map protection
|
|
*
|
|
* => set_max means set max_protection.
|
|
* => map must be unlocked.
|
|
*/
|
|
|
|
#define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \
|
|
~VM_PROT_WRITE : VM_PROT_ALL)
|
|
|
|
int
|
|
uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
vm_prot_t new_prot, bool set_max)
|
|
{
|
|
struct vm_map_entry *current, *entry;
|
|
int error = 0;
|
|
UVMHIST_FUNC("uvm_map_protect"); UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_prot=0x%x)",
|
|
map, start, end, new_prot);
|
|
|
|
vm_map_lock(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
if (uvm_map_lookup_entry(map, start, &entry)) {
|
|
UVM_MAP_CLIP_START(map, entry, start, NULL);
|
|
} else {
|
|
entry = entry->next;
|
|
}
|
|
|
|
/*
|
|
* make a first pass to check for protection violations.
|
|
*/
|
|
|
|
current = entry;
|
|
while ((current != &map->header) && (current->start < end)) {
|
|
if (UVM_ET_ISSUBMAP(current)) {
|
|
error = EINVAL;
|
|
goto out;
|
|
}
|
|
if ((new_prot & current->max_protection) != new_prot) {
|
|
error = EACCES;
|
|
goto out;
|
|
}
|
|
/*
|
|
* Don't allow VM_PROT_EXECUTE to be set on entries that
|
|
* point to vnodes that are associated with a NOEXEC file
|
|
* system.
|
|
*/
|
|
if (UVM_ET_ISOBJ(current) &&
|
|
UVM_OBJ_IS_VNODE(current->object.uvm_obj)) {
|
|
struct vnode *vp =
|
|
(struct vnode *) current->object.uvm_obj;
|
|
|
|
if ((new_prot & VM_PROT_EXECUTE) != 0 &&
|
|
(vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) {
|
|
error = EACCES;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
current = current->next;
|
|
}
|
|
|
|
/* go back and fix up protections (no need to clip this time). */
|
|
|
|
current = entry;
|
|
while ((current != &map->header) && (current->start < end)) {
|
|
vm_prot_t old_prot;
|
|
|
|
UVM_MAP_CLIP_END(map, current, end, NULL);
|
|
old_prot = current->protection;
|
|
if (set_max)
|
|
current->protection =
|
|
(current->max_protection = new_prot) & old_prot;
|
|
else
|
|
current->protection = new_prot;
|
|
|
|
/*
|
|
* update physical map if necessary. worry about copy-on-write
|
|
* here -- CHECK THIS XXX
|
|
*/
|
|
|
|
if (current->protection != old_prot) {
|
|
/* update pmap! */
|
|
pmap_protect(map->pmap, current->start, current->end,
|
|
current->protection & MASK(entry));
|
|
|
|
/*
|
|
* If this entry points at a vnode, and the
|
|
* protection includes VM_PROT_EXECUTE, mark
|
|
* the vnode as VEXECMAP.
|
|
*/
|
|
if (UVM_ET_ISOBJ(current)) {
|
|
struct uvm_object *uobj =
|
|
current->object.uvm_obj;
|
|
|
|
if (UVM_OBJ_IS_VNODE(uobj) &&
|
|
(current->protection & VM_PROT_EXECUTE)) {
|
|
simple_lock(&uobj->vmobjlock);
|
|
vn_markexec((struct vnode *) uobj);
|
|
simple_unlock(&uobj->vmobjlock);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If the map is configured to lock any future mappings,
|
|
* wire this entry now if the old protection was VM_PROT_NONE
|
|
* and the new protection is not VM_PROT_NONE.
|
|
*/
|
|
|
|
if ((map->flags & VM_MAP_WIREFUTURE) != 0 &&
|
|
VM_MAPENT_ISWIRED(entry) == 0 &&
|
|
old_prot == VM_PROT_NONE &&
|
|
new_prot != VM_PROT_NONE) {
|
|
if (uvm_map_pageable(map, entry->start,
|
|
entry->end, false,
|
|
UVM_LK_ENTER|UVM_LK_EXIT) != 0) {
|
|
|
|
/*
|
|
* If locking the entry fails, remember the
|
|
* error if it's the first one. Note we
|
|
* still continue setting the protection in
|
|
* the map, but will return the error
|
|
* condition regardless.
|
|
*
|
|
* XXX Ignore what the actual error is,
|
|
* XXX just call it a resource shortage
|
|
* XXX so that it doesn't get confused
|
|
* XXX what uvm_map_protect() itself would
|
|
* XXX normally return.
|
|
*/
|
|
|
|
error = ENOMEM;
|
|
}
|
|
}
|
|
current = current->next;
|
|
}
|
|
pmap_update(map->pmap);
|
|
|
|
out:
|
|
vm_map_unlock(map);
|
|
|
|
UVMHIST_LOG(maphist, "<- done, error=%d",error,0,0,0);
|
|
return error;
|
|
}
|
|
|
|
#undef MASK
|
|
|
|
/*
|
|
* uvm_map_inherit: set inheritance code for range of addrs in map.
|
|
*
|
|
* => map must be unlocked
|
|
* => note that the inherit code is used during a "fork". see fork
|
|
* code for details.
|
|
*/
|
|
|
|
int
|
|
uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
vm_inherit_t new_inheritance)
|
|
{
|
|
struct vm_map_entry *entry, *temp_entry;
|
|
UVMHIST_FUNC("uvm_map_inherit"); UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_inh=0x%x)",
|
|
map, start, end, new_inheritance);
|
|
|
|
switch (new_inheritance) {
|
|
case MAP_INHERIT_NONE:
|
|
case MAP_INHERIT_COPY:
|
|
case MAP_INHERIT_SHARE:
|
|
break;
|
|
default:
|
|
UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0);
|
|
return EINVAL;
|
|
}
|
|
|
|
vm_map_lock(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
if (uvm_map_lookup_entry(map, start, &temp_entry)) {
|
|
entry = temp_entry;
|
|
UVM_MAP_CLIP_START(map, entry, start, NULL);
|
|
} else {
|
|
entry = temp_entry->next;
|
|
}
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
UVM_MAP_CLIP_END(map, entry, end, NULL);
|
|
entry->inheritance = new_inheritance;
|
|
entry = entry->next;
|
|
}
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_advice: set advice code for range of addrs in map.
|
|
*
|
|
* => map must be unlocked
|
|
*/
|
|
|
|
int
|
|
uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice)
|
|
{
|
|
struct vm_map_entry *entry, *temp_entry;
|
|
UVMHIST_FUNC("uvm_map_advice"); UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_adv=0x%x)",
|
|
map, start, end, new_advice);
|
|
|
|
vm_map_lock(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
if (uvm_map_lookup_entry(map, start, &temp_entry)) {
|
|
entry = temp_entry;
|
|
UVM_MAP_CLIP_START(map, entry, start, NULL);
|
|
} else {
|
|
entry = temp_entry->next;
|
|
}
|
|
|
|
/*
|
|
* XXXJRT: disallow holes?
|
|
*/
|
|
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
UVM_MAP_CLIP_END(map, entry, end, NULL);
|
|
|
|
switch (new_advice) {
|
|
case MADV_NORMAL:
|
|
case MADV_RANDOM:
|
|
case MADV_SEQUENTIAL:
|
|
/* nothing special here */
|
|
break;
|
|
|
|
default:
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0);
|
|
return EINVAL;
|
|
}
|
|
entry->advice = new_advice;
|
|
entry = entry->next;
|
|
}
|
|
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_pageable: sets the pageability of a range in a map.
|
|
*
|
|
* => wires map entries. should not be used for transient page locking.
|
|
* for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()).
|
|
* => regions specified as not pageable require lock-down (wired) memory
|
|
* and page tables.
|
|
* => map must never be read-locked
|
|
* => if islocked is true, map is already write-locked
|
|
* => we always unlock the map, since we must downgrade to a read-lock
|
|
* to call uvm_fault_wire()
|
|
* => XXXCDC: check this and try and clean it up.
|
|
*/
|
|
|
|
int
|
|
uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
bool new_pageable, int lockflags)
|
|
{
|
|
struct vm_map_entry *entry, *start_entry, *failed_entry;
|
|
int rv;
|
|
#ifdef DIAGNOSTIC
|
|
u_int timestamp_save;
|
|
#endif
|
|
UVMHIST_FUNC("uvm_map_pageable"); UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_pageable=0x%x)",
|
|
map, start, end, new_pageable);
|
|
KASSERT(map->flags & VM_MAP_PAGEABLE);
|
|
|
|
if ((lockflags & UVM_LK_ENTER) == 0)
|
|
vm_map_lock(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
|
|
/*
|
|
* only one pageability change may take place at one time, since
|
|
* uvm_fault_wire assumes it will be called only once for each
|
|
* wiring/unwiring. therefore, we have to make sure we're actually
|
|
* changing the pageability for the entire region. we do so before
|
|
* making any changes.
|
|
*/
|
|
|
|
if (uvm_map_lookup_entry(map, start, &start_entry) == false) {
|
|
if ((lockflags & UVM_LK_EXIT) == 0)
|
|
vm_map_unlock(map);
|
|
|
|
UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0);
|
|
return EFAULT;
|
|
}
|
|
entry = start_entry;
|
|
|
|
/*
|
|
* handle wiring and unwiring separately.
|
|
*/
|
|
|
|
if (new_pageable) { /* unwire */
|
|
UVM_MAP_CLIP_START(map, entry, start, NULL);
|
|
|
|
/*
|
|
* unwiring. first ensure that the range to be unwired is
|
|
* really wired down and that there are no holes.
|
|
*/
|
|
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
if (entry->wired_count == 0 ||
|
|
(entry->end < end &&
|
|
(entry->next == &map->header ||
|
|
entry->next->start > entry->end))) {
|
|
if ((lockflags & UVM_LK_EXIT) == 0)
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0);
|
|
return EINVAL;
|
|
}
|
|
entry = entry->next;
|
|
}
|
|
|
|
/*
|
|
* POSIX 1003.1b - a single munlock call unlocks a region,
|
|
* regardless of the number of mlock calls made on that
|
|
* region.
|
|
*/
|
|
|
|
entry = start_entry;
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
UVM_MAP_CLIP_END(map, entry, end, NULL);
|
|
if (VM_MAPENT_ISWIRED(entry))
|
|
uvm_map_entry_unwire(map, entry);
|
|
entry = entry->next;
|
|
}
|
|
if ((lockflags & UVM_LK_EXIT) == 0)
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* wire case: in two passes [XXXCDC: ugly block of code here]
|
|
*
|
|
* 1: holding the write lock, we create any anonymous maps that need
|
|
* to be created. then we clip each map entry to the region to
|
|
* be wired and increment its wiring count.
|
|
*
|
|
* 2: we downgrade to a read lock, and call uvm_fault_wire to fault
|
|
* in the pages for any newly wired area (wired_count == 1).
|
|
*
|
|
* downgrading to a read lock for uvm_fault_wire avoids a possible
|
|
* deadlock with another thread that may have faulted on one of
|
|
* the pages to be wired (it would mark the page busy, blocking
|
|
* us, then in turn block on the map lock that we hold). because
|
|
* of problems in the recursive lock package, we cannot upgrade
|
|
* to a write lock in vm_map_lookup. thus, any actions that
|
|
* require the write lock must be done beforehand. because we
|
|
* keep the read lock on the map, the copy-on-write status of the
|
|
* entries we modify here cannot change.
|
|
*/
|
|
|
|
while ((entry != &map->header) && (entry->start < end)) {
|
|
if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */
|
|
|
|
/*
|
|
* perform actions of vm_map_lookup that need the
|
|
* write lock on the map: create an anonymous map
|
|
* for a copy-on-write region, or an anonymous map
|
|
* for a zero-fill region. (XXXCDC: submap case
|
|
* ok?)
|
|
*/
|
|
|
|
if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */
|
|
if (UVM_ET_ISNEEDSCOPY(entry) &&
|
|
((entry->max_protection & VM_PROT_WRITE) ||
|
|
(entry->object.uvm_obj == NULL))) {
|
|
amap_copy(map, entry, 0, start, end);
|
|
/* XXXCDC: wait OK? */
|
|
}
|
|
}
|
|
}
|
|
UVM_MAP_CLIP_START(map, entry, start, NULL);
|
|
UVM_MAP_CLIP_END(map, entry, end, NULL);
|
|
entry->wired_count++;
|
|
|
|
/*
|
|
* Check for holes
|
|
*/
|
|
|
|
if (entry->protection == VM_PROT_NONE ||
|
|
(entry->end < end &&
|
|
(entry->next == &map->header ||
|
|
entry->next->start > entry->end))) {
|
|
|
|
/*
|
|
* found one. amap creation actions do not need to
|
|
* be undone, but the wired counts need to be restored.
|
|
*/
|
|
|
|
while (entry != &map->header && entry->end > start) {
|
|
entry->wired_count--;
|
|
entry = entry->prev;
|
|
}
|
|
if ((lockflags & UVM_LK_EXIT) == 0)
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0);
|
|
return EINVAL;
|
|
}
|
|
entry = entry->next;
|
|
}
|
|
|
|
/*
|
|
* Pass 2.
|
|
*/
|
|
|
|
#ifdef DIAGNOSTIC
|
|
timestamp_save = map->timestamp;
|
|
#endif
|
|
vm_map_busy(map);
|
|
vm_map_downgrade(map);
|
|
|
|
rv = 0;
|
|
entry = start_entry;
|
|
while (entry != &map->header && entry->start < end) {
|
|
if (entry->wired_count == 1) {
|
|
rv = uvm_fault_wire(map, entry->start, entry->end,
|
|
entry->max_protection, 1);
|
|
if (rv) {
|
|
|
|
/*
|
|
* wiring failed. break out of the loop.
|
|
* we'll clean up the map below, once we
|
|
* have a write lock again.
|
|
*/
|
|
|
|
break;
|
|
}
|
|
}
|
|
entry = entry->next;
|
|
}
|
|
|
|
if (rv) { /* failed? */
|
|
|
|
/*
|
|
* Get back to an exclusive (write) lock.
|
|
*/
|
|
|
|
vm_map_upgrade(map);
|
|
vm_map_unbusy(map);
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (timestamp_save != map->timestamp)
|
|
panic("uvm_map_pageable: stale map");
|
|
#endif
|
|
|
|
/*
|
|
* first drop the wiring count on all the entries
|
|
* which haven't actually been wired yet.
|
|
*/
|
|
|
|
failed_entry = entry;
|
|
while (entry != &map->header && entry->start < end) {
|
|
entry->wired_count--;
|
|
entry = entry->next;
|
|
}
|
|
|
|
/*
|
|
* now, unwire all the entries that were successfully
|
|
* wired above.
|
|
*/
|
|
|
|
entry = start_entry;
|
|
while (entry != failed_entry) {
|
|
entry->wired_count--;
|
|
if (VM_MAPENT_ISWIRED(entry) == 0)
|
|
uvm_map_entry_unwire(map, entry);
|
|
entry = entry->next;
|
|
}
|
|
if ((lockflags & UVM_LK_EXIT) == 0)
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist, "<- done (RV=%d)", rv,0,0,0);
|
|
return (rv);
|
|
}
|
|
|
|
/* We are holding a read lock here. */
|
|
if ((lockflags & UVM_LK_EXIT) == 0) {
|
|
vm_map_unbusy(map);
|
|
vm_map_unlock_read(map);
|
|
} else {
|
|
|
|
/*
|
|
* Get back to an exclusive (write) lock.
|
|
*/
|
|
|
|
vm_map_upgrade(map);
|
|
vm_map_unbusy(map);
|
|
}
|
|
|
|
UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_pageable_all: special case of uvm_map_pageable - affects
|
|
* all mapped regions.
|
|
*
|
|
* => map must not be locked.
|
|
* => if no flags are specified, all regions are unwired.
|
|
* => XXXJRT: has some of the same problems as uvm_map_pageable() above.
|
|
*/
|
|
|
|
int
|
|
uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit)
|
|
{
|
|
struct vm_map_entry *entry, *failed_entry;
|
|
vsize_t size;
|
|
int rv;
|
|
#ifdef DIAGNOSTIC
|
|
u_int timestamp_save;
|
|
#endif
|
|
UVMHIST_FUNC("uvm_map_pageable_all"); UVMHIST_CALLED(maphist);
|
|
UVMHIST_LOG(maphist,"(map=0x%x,flags=0x%x)", map, flags, 0, 0);
|
|
|
|
KASSERT(map->flags & VM_MAP_PAGEABLE);
|
|
|
|
vm_map_lock(map);
|
|
|
|
/*
|
|
* handle wiring and unwiring separately.
|
|
*/
|
|
|
|
if (flags == 0) { /* unwire */
|
|
|
|
/*
|
|
* POSIX 1003.1b -- munlockall unlocks all regions,
|
|
* regardless of how many times mlockall has been called.
|
|
*/
|
|
|
|
for (entry = map->header.next; entry != &map->header;
|
|
entry = entry->next) {
|
|
if (VM_MAPENT_ISWIRED(entry))
|
|
uvm_map_entry_unwire(map, entry);
|
|
}
|
|
map->flags &= ~VM_MAP_WIREFUTURE;
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
if (flags & MCL_FUTURE) {
|
|
|
|
/*
|
|
* must wire all future mappings; remember this.
|
|
*/
|
|
|
|
map->flags |= VM_MAP_WIREFUTURE;
|
|
}
|
|
|
|
if ((flags & MCL_CURRENT) == 0) {
|
|
|
|
/*
|
|
* no more work to do!
|
|
*/
|
|
|
|
UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0);
|
|
vm_map_unlock(map);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* wire case: in three passes [XXXCDC: ugly block of code here]
|
|
*
|
|
* 1: holding the write lock, count all pages mapped by non-wired
|
|
* entries. if this would cause us to go over our limit, we fail.
|
|
*
|
|
* 2: still holding the write lock, we create any anonymous maps that
|
|
* need to be created. then we increment its wiring count.
|
|
*
|
|
* 3: we downgrade to a read lock, and call uvm_fault_wire to fault
|
|
* in the pages for any newly wired area (wired_count == 1).
|
|
*
|
|
* downgrading to a read lock for uvm_fault_wire avoids a possible
|
|
* deadlock with another thread that may have faulted on one of
|
|
* the pages to be wired (it would mark the page busy, blocking
|
|
* us, then in turn block on the map lock that we hold). because
|
|
* of problems in the recursive lock package, we cannot upgrade
|
|
* to a write lock in vm_map_lookup. thus, any actions that
|
|
* require the write lock must be done beforehand. because we
|
|
* keep the read lock on the map, the copy-on-write status of the
|
|
* entries we modify here cannot change.
|
|
*/
|
|
|
|
for (size = 0, entry = map->header.next; entry != &map->header;
|
|
entry = entry->next) {
|
|
if (entry->protection != VM_PROT_NONE &&
|
|
VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */
|
|
size += entry->end - entry->start;
|
|
}
|
|
}
|
|
|
|
if (atop(size) + uvmexp.wired > uvmexp.wiredmax) {
|
|
vm_map_unlock(map);
|
|
return ENOMEM;
|
|
}
|
|
|
|
if (limit != 0 &&
|
|
(size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) {
|
|
vm_map_unlock(map);
|
|
return ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* Pass 2.
|
|
*/
|
|
|
|
for (entry = map->header.next; entry != &map->header;
|
|
entry = entry->next) {
|
|
if (entry->protection == VM_PROT_NONE)
|
|
continue;
|
|
if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */
|
|
|
|
/*
|
|
* perform actions of vm_map_lookup that need the
|
|
* write lock on the map: create an anonymous map
|
|
* for a copy-on-write region, or an anonymous map
|
|
* for a zero-fill region. (XXXCDC: submap case
|
|
* ok?)
|
|
*/
|
|
|
|
if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */
|
|
if (UVM_ET_ISNEEDSCOPY(entry) &&
|
|
((entry->max_protection & VM_PROT_WRITE) ||
|
|
(entry->object.uvm_obj == NULL))) {
|
|
amap_copy(map, entry, 0, entry->start,
|
|
entry->end);
|
|
/* XXXCDC: wait OK? */
|
|
}
|
|
}
|
|
}
|
|
entry->wired_count++;
|
|
}
|
|
|
|
/*
|
|
* Pass 3.
|
|
*/
|
|
|
|
#ifdef DIAGNOSTIC
|
|
timestamp_save = map->timestamp;
|
|
#endif
|
|
vm_map_busy(map);
|
|
vm_map_downgrade(map);
|
|
|
|
rv = 0;
|
|
for (entry = map->header.next; entry != &map->header;
|
|
entry = entry->next) {
|
|
if (entry->wired_count == 1) {
|
|
rv = uvm_fault_wire(map, entry->start, entry->end,
|
|
entry->max_protection, 1);
|
|
if (rv) {
|
|
|
|
/*
|
|
* wiring failed. break out of the loop.
|
|
* we'll clean up the map below, once we
|
|
* have a write lock again.
|
|
*/
|
|
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (rv) {
|
|
|
|
/*
|
|
* Get back an exclusive (write) lock.
|
|
*/
|
|
|
|
vm_map_upgrade(map);
|
|
vm_map_unbusy(map);
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (timestamp_save != map->timestamp)
|
|
panic("uvm_map_pageable_all: stale map");
|
|
#endif
|
|
|
|
/*
|
|
* first drop the wiring count on all the entries
|
|
* which haven't actually been wired yet.
|
|
*
|
|
* Skip VM_PROT_NONE entries like we did above.
|
|
*/
|
|
|
|
failed_entry = entry;
|
|
for (/* nothing */; entry != &map->header;
|
|
entry = entry->next) {
|
|
if (entry->protection == VM_PROT_NONE)
|
|
continue;
|
|
entry->wired_count--;
|
|
}
|
|
|
|
/*
|
|
* now, unwire all the entries that were successfully
|
|
* wired above.
|
|
*
|
|
* Skip VM_PROT_NONE entries like we did above.
|
|
*/
|
|
|
|
for (entry = map->header.next; entry != failed_entry;
|
|
entry = entry->next) {
|
|
if (entry->protection == VM_PROT_NONE)
|
|
continue;
|
|
entry->wired_count--;
|
|
if (VM_MAPENT_ISWIRED(entry))
|
|
uvm_map_entry_unwire(map, entry);
|
|
}
|
|
vm_map_unlock(map);
|
|
UVMHIST_LOG(maphist,"<- done (RV=%d)", rv,0,0,0);
|
|
return (rv);
|
|
}
|
|
|
|
/* We are holding a read lock here. */
|
|
vm_map_unbusy(map);
|
|
vm_map_unlock_read(map);
|
|
|
|
UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* uvm_map_clean: clean out a map range
|
|
*
|
|
* => valid flags:
|
|
* if (flags & PGO_CLEANIT): dirty pages are cleaned first
|
|
* if (flags & PGO_SYNCIO): dirty pages are written synchronously
|
|
* if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean
|
|
* if (flags & PGO_FREE): any cached pages are freed after clean
|
|
* => returns an error if any part of the specified range isn't mapped
|
|
* => never a need to flush amap layer since the anonymous memory has
|
|
* no permanent home, but may deactivate pages there
|
|
* => called from sys_msync() and sys_madvise()
|
|
* => caller must not write-lock map (read OK).
|
|
* => we may sleep while cleaning if SYNCIO [with map read-locked]
|
|
*/
|
|
|
|
int
|
|
uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags)
|
|
{
|
|
struct vm_map_entry *current, *entry;
|
|
struct uvm_object *uobj;
|
|
struct vm_amap *amap;
|
|
struct vm_anon *anon;
|
|
struct vm_page *pg;
|
|
vaddr_t offset;
|
|
vsize_t size;
|
|
voff_t uoff;
|
|
int error, refs;
|
|
UVMHIST_FUNC("uvm_map_clean"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,flags=0x%x)",
|
|
map, start, end, flags);
|
|
KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) !=
|
|
(PGO_FREE|PGO_DEACTIVATE));
|
|
|
|
vm_map_lock_read(map);
|
|
VM_MAP_RANGE_CHECK(map, start, end);
|
|
if (uvm_map_lookup_entry(map, start, &entry) == false) {
|
|
vm_map_unlock_read(map);
|
|
return EFAULT;
|
|
}
|
|
|
|
/*
|
|
* Make a first pass to check for holes and wiring problems.
|
|
*/
|
|
|
|
for (current = entry; current->start < end; current = current->next) {
|
|
if (UVM_ET_ISSUBMAP(current)) {
|
|
vm_map_unlock_read(map);
|
|
return EINVAL;
|
|
}
|
|
if ((flags & PGO_FREE) != 0 && VM_MAPENT_ISWIRED(entry)) {
|
|
vm_map_unlock_read(map);
|
|
return EBUSY;
|
|
}
|
|
if (end <= current->end) {
|
|
break;
|
|
}
|
|
if (current->end != current->next->start) {
|
|
vm_map_unlock_read(map);
|
|
return EFAULT;
|
|
}
|
|
}
|
|
|
|
error = 0;
|
|
for (current = entry; start < end; current = current->next) {
|
|
amap = current->aref.ar_amap; /* top layer */
|
|
uobj = current->object.uvm_obj; /* bottom layer */
|
|
KASSERT(start >= current->start);
|
|
|
|
/*
|
|
* No amap cleaning necessary if:
|
|
*
|
|
* (1) There's no amap.
|
|
*
|
|
* (2) We're not deactivating or freeing pages.
|
|
*/
|
|
|
|
if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0)
|
|
goto flush_object;
|
|
|
|
amap_lock(amap);
|
|
offset = start - current->start;
|
|
size = MIN(end, current->end) - start;
|
|
for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) {
|
|
anon = amap_lookup(¤t->aref, offset);
|
|
if (anon == NULL)
|
|
continue;
|
|
|
|
simple_lock(&anon->an_lock);
|
|
pg = anon->an_page;
|
|
if (pg == NULL) {
|
|
simple_unlock(&anon->an_lock);
|
|
continue;
|
|
}
|
|
|
|
switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) {
|
|
|
|
/*
|
|
* In these first 3 cases, we just deactivate the page.
|
|
*/
|
|
|
|
case PGO_CLEANIT|PGO_FREE:
|
|
case PGO_CLEANIT|PGO_DEACTIVATE:
|
|
case PGO_DEACTIVATE:
|
|
deactivate_it:
|
|
/*
|
|
* skip the page if it's loaned or wired,
|
|
* since it shouldn't be on a paging queue
|
|
* at all in these cases.
|
|
*/
|
|
|
|
uvm_lock_pageq();
|
|
if (pg->loan_count != 0 ||
|
|
pg->wire_count != 0) {
|
|
uvm_unlock_pageq();
|
|
simple_unlock(&anon->an_lock);
|
|
continue;
|
|
}
|
|
KASSERT(pg->uanon == anon);
|
|
pmap_clear_reference(pg);
|
|
uvm_pagedeactivate(pg);
|
|
uvm_unlock_pageq();
|
|
simple_unlock(&anon->an_lock);
|
|
continue;
|
|
|
|
case PGO_FREE:
|
|
|
|
/*
|
|
* If there are multiple references to
|
|
* the amap, just deactivate the page.
|
|
*/
|
|
|
|
if (amap_refs(amap) > 1)
|
|
goto deactivate_it;
|
|
|
|
/* skip the page if it's wired */
|
|
if (pg->wire_count != 0) {
|
|
simple_unlock(&anon->an_lock);
|
|
continue;
|
|
}
|
|
amap_unadd(¤t->aref, offset);
|
|
refs = --anon->an_ref;
|
|
simple_unlock(&anon->an_lock);
|
|
if (refs == 0)
|
|
uvm_anfree(anon);
|
|
continue;
|
|
}
|
|
}
|
|
amap_unlock(amap);
|
|
|
|
flush_object:
|
|
/*
|
|
* flush pages if we've got a valid backing object.
|
|
* note that we must always clean object pages before
|
|
* freeing them since otherwise we could reveal stale
|
|
* data from files.
|
|
*/
|
|
|
|
uoff = current->offset + (start - current->start);
|
|
size = MIN(end, current->end) - start;
|
|
if (uobj != NULL) {
|
|
simple_lock(&uobj->vmobjlock);
|
|
if (uobj->pgops->pgo_put != NULL)
|
|
error = (uobj->pgops->pgo_put)(uobj, uoff,
|
|
uoff + size, flags | PGO_CLEANIT);
|
|
else
|
|
error = 0;
|
|
}
|
|
start += size;
|
|
}
|
|
vm_map_unlock_read(map);
|
|
return (error);
|
|
}
|
|
|
|
|
|
/*
|
|
* uvm_map_checkprot: check protection in map
|
|
*
|
|
* => must allow specified protection in a fully allocated region.
|
|
* => map must be read or write locked by caller.
|
|
*/
|
|
|
|
bool
|
|
uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end,
|
|
vm_prot_t protection)
|
|
{
|
|
struct vm_map_entry *entry;
|
|
struct vm_map_entry *tmp_entry;
|
|
|
|
if (!uvm_map_lookup_entry(map, start, &tmp_entry)) {
|
|
return (false);
|
|
}
|
|
entry = tmp_entry;
|
|
while (start < end) {
|
|
if (entry == &map->header) {
|
|
return (false);
|
|
}
|
|
|
|
/*
|
|
* no holes allowed
|
|
*/
|
|
|
|
if (start < entry->start) {
|
|
return (false);
|
|
}
|
|
|
|
/*
|
|
* check protection associated with entry
|
|
*/
|
|
|
|
if ((entry->protection & protection) != protection) {
|
|
return (false);
|
|
}
|
|
start = entry->end;
|
|
entry = entry->next;
|
|
}
|
|
return (true);
|
|
}
|
|
|
|
/*
|
|
* uvmspace_alloc: allocate a vmspace structure.
|
|
*
|
|
* - structure includes vm_map and pmap
|
|
* - XXX: no locking on this structure
|
|
* - refcnt set to 1, rest must be init'd by caller
|
|
*/
|
|
struct vmspace *
|
|
uvmspace_alloc(vaddr_t vmin, vaddr_t vmax)
|
|
{
|
|
struct vmspace *vm;
|
|
UVMHIST_FUNC("uvmspace_alloc"); UVMHIST_CALLED(maphist);
|
|
|
|
vm = pool_get(&uvm_vmspace_pool, PR_WAITOK);
|
|
uvmspace_init(vm, NULL, vmin, vmax);
|
|
UVMHIST_LOG(maphist,"<- done (vm=0x%x)", vm,0,0,0);
|
|
return (vm);
|
|
}
|
|
|
|
/*
|
|
* uvmspace_init: initialize a vmspace structure.
|
|
*
|
|
* - XXX: no locking on this structure
|
|
* - refcnt set to 1, rest must be init'd by caller
|
|
*/
|
|
void
|
|
uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, vaddr_t vmax)
|
|
{
|
|
UVMHIST_FUNC("uvmspace_init"); UVMHIST_CALLED(maphist);
|
|
|
|
memset(vm, 0, sizeof(*vm));
|
|
uvm_map_setup(&vm->vm_map, vmin, vmax, VM_MAP_PAGEABLE
|
|
#ifdef __USING_TOPDOWN_VM
|
|
| VM_MAP_TOPDOWN
|
|
#endif
|
|
);
|
|
if (pmap)
|
|
pmap_reference(pmap);
|
|
else
|
|
pmap = pmap_create();
|
|
vm->vm_map.pmap = pmap;
|
|
vm->vm_refcnt = 1;
|
|
UVMHIST_LOG(maphist,"<- done",0,0,0,0);
|
|
}
|
|
|
|
/*
|
|
* uvmspace_share: share a vmspace between two processes
|
|
*
|
|
* - used for vfork, threads(?)
|
|
*/
|
|
|
|
void
|
|
uvmspace_share(struct proc *p1, struct proc *p2)
|
|
{
|
|
|
|
uvmspace_addref(p1->p_vmspace);
|
|
p2->p_vmspace = p1->p_vmspace;
|
|
}
|
|
|
|
/*
|
|
* uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace
|
|
*
|
|
* - XXX: no locking on vmspace
|
|
*/
|
|
|
|
void
|
|
uvmspace_unshare(struct lwp *l)
|
|
{
|
|
struct proc *p = l->l_proc;
|
|
struct vmspace *nvm, *ovm = p->p_vmspace;
|
|
|
|
if (ovm->vm_refcnt == 1)
|
|
/* nothing to do: vmspace isn't shared in the first place */
|
|
return;
|
|
|
|
/* make a new vmspace, still holding old one */
|
|
nvm = uvmspace_fork(ovm);
|
|
|
|
pmap_deactivate(l); /* unbind old vmspace */
|
|
p->p_vmspace = nvm;
|
|
pmap_activate(l); /* switch to new vmspace */
|
|
|
|
uvmspace_free(ovm); /* drop reference to old vmspace */
|
|
}
|
|
|
|
/*
|
|
* uvmspace_exec: the process wants to exec a new program
|
|
*/
|
|
|
|
void
|
|
uvmspace_exec(struct lwp *l, vaddr_t start, vaddr_t end)
|
|
{
|
|
struct proc *p = l->l_proc;
|
|
struct vmspace *nvm, *ovm = p->p_vmspace;
|
|
struct vm_map *map = &ovm->vm_map;
|
|
|
|
#ifdef __sparc__
|
|
/* XXX cgd 960926: the sparc #ifdef should be a MD hook */
|
|
kill_user_windows(l); /* before stack addresses go away */
|
|
#endif
|
|
|
|
/*
|
|
* see if more than one process is using this vmspace...
|
|
*/
|
|
|
|
if (ovm->vm_refcnt == 1) {
|
|
|
|
/*
|
|
* if p is the only process using its vmspace then we can safely
|
|
* recycle that vmspace for the program that is being exec'd.
|
|
*/
|
|
|
|
#ifdef SYSVSHM
|
|
/*
|
|
* SYSV SHM semantics require us to kill all segments on an exec
|
|
*/
|
|
|
|
if (ovm->vm_shm)
|
|
shmexit(ovm);
|
|
#endif
|
|
|
|
/*
|
|
* POSIX 1003.1b -- "lock future mappings" is revoked
|
|
* when a process execs another program image.
|
|
*/
|
|
|
|
map->flags &= ~VM_MAP_WIREFUTURE;
|
|
|
|
/*
|
|
* now unmap the old program
|
|
*/
|
|
|
|
pmap_remove_all(map->pmap);
|
|
uvm_unmap(map, vm_map_min(map), vm_map_max(map));
|
|
KASSERT(map->header.prev == &map->header);
|
|
KASSERT(map->nentries == 0);
|
|
|
|
/*
|
|
* resize the map
|
|
*/
|
|
|
|
vm_map_setmin(map, start);
|
|
vm_map_setmax(map, end);
|
|
} else {
|
|
|
|
/*
|
|
* p's vmspace is being shared, so we can't reuse it for p since
|
|
* it is still being used for others. allocate a new vmspace
|
|
* for p
|
|
*/
|
|
|
|
nvm = uvmspace_alloc(start, end);
|
|
|
|
/*
|
|
* install new vmspace and drop our ref to the old one.
|
|
*/
|
|
|
|
pmap_deactivate(l);
|
|
p->p_vmspace = nvm;
|
|
pmap_activate(l);
|
|
|
|
uvmspace_free(ovm);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvmspace_addref: add a referece to a vmspace.
|
|
*/
|
|
|
|
void
|
|
uvmspace_addref(struct vmspace *vm)
|
|
{
|
|
struct vm_map *map = &vm->vm_map;
|
|
|
|
KASSERT((map->flags & VM_MAP_DYING) == 0);
|
|
|
|
mutex_enter(&map->misc_lock);
|
|
KASSERT(vm->vm_refcnt > 0);
|
|
vm->vm_refcnt++;
|
|
mutex_exit(&map->misc_lock);
|
|
}
|
|
|
|
/*
|
|
* uvmspace_free: free a vmspace data structure
|
|
*/
|
|
|
|
void
|
|
uvmspace_free(struct vmspace *vm)
|
|
{
|
|
struct vm_map_entry *dead_entries;
|
|
struct vm_map *map = &vm->vm_map;
|
|
int n;
|
|
|
|
UVMHIST_FUNC("uvmspace_free"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist,"(vm=0x%x) ref=%d", vm, vm->vm_refcnt,0,0);
|
|
mutex_enter(&map->misc_lock);
|
|
n = --vm->vm_refcnt;
|
|
mutex_exit(&map->misc_lock);
|
|
if (n > 0)
|
|
return;
|
|
|
|
/*
|
|
* at this point, there should be no other references to the map.
|
|
* delete all of the mappings, then destroy the pmap.
|
|
*/
|
|
|
|
map->flags |= VM_MAP_DYING;
|
|
pmap_remove_all(map->pmap);
|
|
#ifdef SYSVSHM
|
|
/* Get rid of any SYSV shared memory segments. */
|
|
if (vm->vm_shm != NULL)
|
|
shmexit(vm);
|
|
#endif
|
|
if (map->nentries) {
|
|
uvm_unmap_remove(map, vm_map_min(map), vm_map_max(map),
|
|
&dead_entries, NULL, 0);
|
|
if (dead_entries != NULL)
|
|
uvm_unmap_detach(dead_entries, 0);
|
|
}
|
|
KASSERT(map->nentries == 0);
|
|
KASSERT(map->size == 0);
|
|
mutex_destroy(&map->misc_lock);
|
|
mutex_destroy(&map->hint_lock);
|
|
mutex_destroy(&map->mutex);
|
|
rw_destroy(&map->lock);
|
|
pmap_destroy(map->pmap);
|
|
pool_put(&uvm_vmspace_pool, vm);
|
|
}
|
|
|
|
/*
|
|
* F O R K - m a i n e n t r y p o i n t
|
|
*/
|
|
/*
|
|
* uvmspace_fork: fork a process' main map
|
|
*
|
|
* => create a new vmspace for child process from parent.
|
|
* => parent's map must not be locked.
|
|
*/
|
|
|
|
struct vmspace *
|
|
uvmspace_fork(struct vmspace *vm1)
|
|
{
|
|
struct vmspace *vm2;
|
|
struct vm_map *old_map = &vm1->vm_map;
|
|
struct vm_map *new_map;
|
|
struct vm_map_entry *old_entry;
|
|
struct vm_map_entry *new_entry;
|
|
UVMHIST_FUNC("uvmspace_fork"); UVMHIST_CALLED(maphist);
|
|
|
|
vm_map_lock(old_map);
|
|
|
|
vm2 = uvmspace_alloc(vm_map_min(old_map), vm_map_max(old_map));
|
|
memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy,
|
|
(char *) (vm1 + 1) - (char *) &vm1->vm_startcopy);
|
|
new_map = &vm2->vm_map; /* XXX */
|
|
|
|
old_entry = old_map->header.next;
|
|
new_map->size = old_map->size;
|
|
|
|
/*
|
|
* go entry-by-entry
|
|
*/
|
|
|
|
while (old_entry != &old_map->header) {
|
|
|
|
/*
|
|
* first, some sanity checks on the old entry
|
|
*/
|
|
|
|
KASSERT(!UVM_ET_ISSUBMAP(old_entry));
|
|
KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) ||
|
|
!UVM_ET_ISNEEDSCOPY(old_entry));
|
|
|
|
switch (old_entry->inheritance) {
|
|
case MAP_INHERIT_NONE:
|
|
|
|
/*
|
|
* drop the mapping, modify size
|
|
*/
|
|
new_map->size -= old_entry->end - old_entry->start;
|
|
break;
|
|
|
|
case MAP_INHERIT_SHARE:
|
|
|
|
/*
|
|
* share the mapping: this means we want the old and
|
|
* new entries to share amaps and backing objects.
|
|
*/
|
|
/*
|
|
* if the old_entry needs a new amap (due to prev fork)
|
|
* then we need to allocate it now so that we have
|
|
* something we own to share with the new_entry. [in
|
|
* other words, we need to clear needs_copy]
|
|
*/
|
|
|
|
if (UVM_ET_ISNEEDSCOPY(old_entry)) {
|
|
/* get our own amap, clears needs_copy */
|
|
amap_copy(old_map, old_entry, AMAP_COPY_NOCHUNK,
|
|
0, 0);
|
|
/* XXXCDC: WAITOK??? */
|
|
}
|
|
|
|
new_entry = uvm_mapent_alloc(new_map, 0);
|
|
/* old_entry -> new_entry */
|
|
uvm_mapent_copy(old_entry, new_entry);
|
|
|
|
/* new pmap has nothing wired in it */
|
|
new_entry->wired_count = 0;
|
|
|
|
/*
|
|
* gain reference to object backing the map (can't
|
|
* be a submap, already checked this case).
|
|
*/
|
|
|
|
if (new_entry->aref.ar_amap)
|
|
uvm_map_reference_amap(new_entry, AMAP_SHARED);
|
|
|
|
if (new_entry->object.uvm_obj &&
|
|
new_entry->object.uvm_obj->pgops->pgo_reference)
|
|
new_entry->object.uvm_obj->
|
|
pgops->pgo_reference(
|
|
new_entry->object.uvm_obj);
|
|
|
|
/* insert entry at end of new_map's entry list */
|
|
uvm_map_entry_link(new_map, new_map->header.prev,
|
|
new_entry);
|
|
|
|
break;
|
|
|
|
case MAP_INHERIT_COPY:
|
|
|
|
/*
|
|
* copy-on-write the mapping (using mmap's
|
|
* MAP_PRIVATE semantics)
|
|
*
|
|
* allocate new_entry, adjust reference counts.
|
|
* (note that new references are read-only).
|
|
*/
|
|
|
|
new_entry = uvm_mapent_alloc(new_map, 0);
|
|
/* old_entry -> new_entry */
|
|
uvm_mapent_copy(old_entry, new_entry);
|
|
|
|
if (new_entry->aref.ar_amap)
|
|
uvm_map_reference_amap(new_entry, 0);
|
|
|
|
if (new_entry->object.uvm_obj &&
|
|
new_entry->object.uvm_obj->pgops->pgo_reference)
|
|
new_entry->object.uvm_obj->pgops->pgo_reference
|
|
(new_entry->object.uvm_obj);
|
|
|
|
/* new pmap has nothing wired in it */
|
|
new_entry->wired_count = 0;
|
|
|
|
new_entry->etype |=
|
|
(UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY);
|
|
uvm_map_entry_link(new_map, new_map->header.prev,
|
|
new_entry);
|
|
|
|
/*
|
|
* the new entry will need an amap. it will either
|
|
* need to be copied from the old entry or created
|
|
* from scratch (if the old entry does not have an
|
|
* amap). can we defer this process until later
|
|
* (by setting "needs_copy") or do we need to copy
|
|
* the amap now?
|
|
*
|
|
* we must copy the amap now if any of the following
|
|
* conditions hold:
|
|
* 1. the old entry has an amap and that amap is
|
|
* being shared. this means that the old (parent)
|
|
* process is sharing the amap with another
|
|
* process. if we do not clear needs_copy here
|
|
* we will end up in a situation where both the
|
|
* parent and child process are refering to the
|
|
* same amap with "needs_copy" set. if the
|
|
* parent write-faults, the fault routine will
|
|
* clear "needs_copy" in the parent by allocating
|
|
* a new amap. this is wrong because the
|
|
* parent is supposed to be sharing the old amap
|
|
* and the new amap will break that.
|
|
*
|
|
* 2. if the old entry has an amap and a non-zero
|
|
* wire count then we are going to have to call
|
|
* amap_cow_now to avoid page faults in the
|
|
* parent process. since amap_cow_now requires
|
|
* "needs_copy" to be clear we might as well
|
|
* clear it here as well.
|
|
*
|
|
*/
|
|
|
|
if (old_entry->aref.ar_amap != NULL) {
|
|
if ((amap_flags(old_entry->aref.ar_amap) &
|
|
AMAP_SHARED) != 0 ||
|
|
VM_MAPENT_ISWIRED(old_entry)) {
|
|
|
|
amap_copy(new_map, new_entry,
|
|
AMAP_COPY_NOCHUNK, 0, 0);
|
|
/* XXXCDC: M_WAITOK ... ok? */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* if the parent's entry is wired down, then the
|
|
* parent process does not want page faults on
|
|
* access to that memory. this means that we
|
|
* cannot do copy-on-write because we can't write
|
|
* protect the old entry. in this case we
|
|
* resolve all copy-on-write faults now, using
|
|
* amap_cow_now. note that we have already
|
|
* allocated any needed amap (above).
|
|
*/
|
|
|
|
if (VM_MAPENT_ISWIRED(old_entry)) {
|
|
|
|
/*
|
|
* resolve all copy-on-write faults now
|
|
* (note that there is nothing to do if
|
|
* the old mapping does not have an amap).
|
|
*/
|
|
if (old_entry->aref.ar_amap)
|
|
amap_cow_now(new_map, new_entry);
|
|
|
|
} else {
|
|
|
|
/*
|
|
* setup mappings to trigger copy-on-write faults
|
|
* we must write-protect the parent if it has
|
|
* an amap and it is not already "needs_copy"...
|
|
* if it is already "needs_copy" then the parent
|
|
* has already been write-protected by a previous
|
|
* fork operation.
|
|
*/
|
|
|
|
if (old_entry->aref.ar_amap &&
|
|
!UVM_ET_ISNEEDSCOPY(old_entry)) {
|
|
if (old_entry->max_protection & VM_PROT_WRITE) {
|
|
pmap_protect(old_map->pmap,
|
|
old_entry->start,
|
|
old_entry->end,
|
|
old_entry->protection &
|
|
~VM_PROT_WRITE);
|
|
pmap_update(old_map->pmap);
|
|
}
|
|
old_entry->etype |= UVM_ET_NEEDSCOPY;
|
|
}
|
|
}
|
|
break;
|
|
} /* end of switch statement */
|
|
old_entry = old_entry->next;
|
|
}
|
|
|
|
vm_map_unlock(old_map);
|
|
|
|
#ifdef SYSVSHM
|
|
if (vm1->vm_shm)
|
|
shmfork(vm1, vm2);
|
|
#endif
|
|
|
|
#ifdef PMAP_FORK
|
|
pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap);
|
|
#endif
|
|
|
|
UVMHIST_LOG(maphist,"<- done",0,0,0,0);
|
|
return (vm2);
|
|
}
|
|
|
|
|
|
/*
|
|
* in-kernel map entry allocation.
|
|
*/
|
|
|
|
struct uvm_kmapent_hdr {
|
|
LIST_ENTRY(uvm_kmapent_hdr) ukh_listq;
|
|
int ukh_nused;
|
|
struct vm_map_entry *ukh_freelist;
|
|
struct vm_map *ukh_map;
|
|
struct vm_map_entry ukh_entries[0];
|
|
};
|
|
|
|
#define UVM_KMAPENT_CHUNK \
|
|
((PAGE_SIZE - sizeof(struct uvm_kmapent_hdr)) \
|
|
/ sizeof(struct vm_map_entry))
|
|
|
|
#define UVM_KHDR_FIND(entry) \
|
|
((struct uvm_kmapent_hdr *)(((vaddr_t)entry) & ~PAGE_MASK))
|
|
|
|
|
|
#ifdef DIAGNOSTIC
|
|
static struct vm_map *
|
|
uvm_kmapent_map(struct vm_map_entry *entry)
|
|
{
|
|
const struct uvm_kmapent_hdr *ukh;
|
|
|
|
ukh = UVM_KHDR_FIND(entry);
|
|
return ukh->ukh_map;
|
|
}
|
|
#endif
|
|
|
|
static inline struct vm_map_entry *
|
|
uvm_kmapent_get(struct uvm_kmapent_hdr *ukh)
|
|
{
|
|
struct vm_map_entry *entry;
|
|
|
|
KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK);
|
|
KASSERT(ukh->ukh_nused >= 0);
|
|
|
|
entry = ukh->ukh_freelist;
|
|
if (entry) {
|
|
KASSERT((entry->flags & (UVM_MAP_KERNEL | UVM_MAP_KMAPENT))
|
|
== UVM_MAP_KERNEL);
|
|
ukh->ukh_freelist = entry->next;
|
|
ukh->ukh_nused++;
|
|
KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK);
|
|
} else {
|
|
KASSERT(ukh->ukh_nused == UVM_KMAPENT_CHUNK);
|
|
}
|
|
|
|
return entry;
|
|
}
|
|
|
|
static inline void
|
|
uvm_kmapent_put(struct uvm_kmapent_hdr *ukh, struct vm_map_entry *entry)
|
|
{
|
|
|
|
KASSERT((entry->flags & (UVM_MAP_KERNEL | UVM_MAP_KMAPENT))
|
|
== UVM_MAP_KERNEL);
|
|
KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK);
|
|
KASSERT(ukh->ukh_nused > 0);
|
|
KASSERT(ukh->ukh_freelist != NULL ||
|
|
ukh->ukh_nused == UVM_KMAPENT_CHUNK);
|
|
KASSERT(ukh->ukh_freelist == NULL ||
|
|
ukh->ukh_nused < UVM_KMAPENT_CHUNK);
|
|
|
|
ukh->ukh_nused--;
|
|
entry->next = ukh->ukh_freelist;
|
|
ukh->ukh_freelist = entry;
|
|
}
|
|
|
|
/*
|
|
* uvm_kmapent_alloc: allocate a map entry for in-kernel map
|
|
*/
|
|
|
|
static struct vm_map_entry *
|
|
uvm_kmapent_alloc(struct vm_map *map, int flags)
|
|
{
|
|
struct vm_page *pg;
|
|
struct uvm_map_args args;
|
|
struct uvm_kmapent_hdr *ukh;
|
|
struct vm_map_entry *entry;
|
|
uvm_flag_t mapflags = UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL,
|
|
UVM_INH_NONE, UVM_ADV_RANDOM, flags | UVM_FLAG_NOMERGE);
|
|
vaddr_t va;
|
|
int error;
|
|
int i;
|
|
|
|
KDASSERT(UVM_KMAPENT_CHUNK > 2);
|
|
KDASSERT(kernel_map != NULL);
|
|
KASSERT(vm_map_pmap(map) == pmap_kernel());
|
|
|
|
UVMMAP_EVCNT_INCR(uke_alloc);
|
|
entry = NULL;
|
|
again:
|
|
/*
|
|
* try to grab an entry from freelist.
|
|
*/
|
|
mutex_spin_enter(&uvm_kentry_lock);
|
|
ukh = LIST_FIRST(&vm_map_to_kernel(map)->vmk_kentry_free);
|
|
if (ukh) {
|
|
entry = uvm_kmapent_get(ukh);
|
|
if (ukh->ukh_nused == UVM_KMAPENT_CHUNK)
|
|
LIST_REMOVE(ukh, ukh_listq);
|
|
}
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
|
|
if (entry)
|
|
return entry;
|
|
|
|
/*
|
|
* there's no free entry for this vm_map.
|
|
* now we need to allocate some vm_map_entry.
|
|
* for simplicity, always allocate one page chunk of them at once.
|
|
*/
|
|
|
|
pg = uvm_pagealloc(NULL, 0, NULL, 0);
|
|
if (__predict_false(pg == NULL)) {
|
|
if (flags & UVM_FLAG_NOWAIT)
|
|
return NULL;
|
|
uvm_wait("kme_alloc");
|
|
goto again;
|
|
}
|
|
|
|
error = uvm_map_prepare(map, 0, PAGE_SIZE, NULL, UVM_UNKNOWN_OFFSET,
|
|
0, mapflags, &args);
|
|
if (error) {
|
|
uvm_pagefree(pg);
|
|
return NULL;
|
|
}
|
|
|
|
va = args.uma_start;
|
|
|
|
pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), VM_PROT_READ|VM_PROT_WRITE);
|
|
pmap_update(vm_map_pmap(map));
|
|
|
|
ukh = (void *)va;
|
|
|
|
/*
|
|
* use the first entry for ukh itsself.
|
|
*/
|
|
|
|
entry = &ukh->ukh_entries[0];
|
|
entry->flags = UVM_MAP_KERNEL | UVM_MAP_KMAPENT;
|
|
error = uvm_map_enter(map, &args, entry);
|
|
KASSERT(error == 0);
|
|
|
|
ukh->ukh_nused = UVM_KMAPENT_CHUNK;
|
|
ukh->ukh_map = map;
|
|
ukh->ukh_freelist = NULL;
|
|
for (i = UVM_KMAPENT_CHUNK - 1; i >= 2; i--) {
|
|
struct vm_map_entry *xentry = &ukh->ukh_entries[i];
|
|
|
|
xentry->flags = UVM_MAP_KERNEL;
|
|
uvm_kmapent_put(ukh, xentry);
|
|
}
|
|
KASSERT(ukh->ukh_nused == 2);
|
|
|
|
mutex_spin_enter(&uvm_kentry_lock);
|
|
LIST_INSERT_HEAD(&vm_map_to_kernel(map)->vmk_kentry_free,
|
|
ukh, ukh_listq);
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
|
|
/*
|
|
* return second entry.
|
|
*/
|
|
|
|
entry = &ukh->ukh_entries[1];
|
|
entry->flags = UVM_MAP_KERNEL;
|
|
UVMMAP_EVCNT_INCR(ukh_alloc);
|
|
return entry;
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_free: free map entry for in-kernel map
|
|
*/
|
|
|
|
static void
|
|
uvm_kmapent_free(struct vm_map_entry *entry)
|
|
{
|
|
struct uvm_kmapent_hdr *ukh;
|
|
struct vm_page *pg;
|
|
struct vm_map *map;
|
|
struct pmap *pmap;
|
|
vaddr_t va;
|
|
paddr_t pa;
|
|
struct vm_map_entry *deadentry;
|
|
|
|
UVMMAP_EVCNT_INCR(uke_free);
|
|
ukh = UVM_KHDR_FIND(entry);
|
|
map = ukh->ukh_map;
|
|
|
|
mutex_spin_enter(&uvm_kentry_lock);
|
|
uvm_kmapent_put(ukh, entry);
|
|
if (ukh->ukh_nused > 1) {
|
|
if (ukh->ukh_nused == UVM_KMAPENT_CHUNK - 1)
|
|
LIST_INSERT_HEAD(
|
|
&vm_map_to_kernel(map)->vmk_kentry_free,
|
|
ukh, ukh_listq);
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* now we can free this ukh.
|
|
*
|
|
* however, keep an empty ukh to avoid ping-pong.
|
|
*/
|
|
|
|
if (LIST_FIRST(&vm_map_to_kernel(map)->vmk_kentry_free) == ukh &&
|
|
LIST_NEXT(ukh, ukh_listq) == NULL) {
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
return;
|
|
}
|
|
LIST_REMOVE(ukh, ukh_listq);
|
|
mutex_spin_exit(&uvm_kentry_lock);
|
|
|
|
KASSERT(ukh->ukh_nused == 1);
|
|
|
|
/*
|
|
* remove map entry for ukh itsself.
|
|
*/
|
|
|
|
va = (vaddr_t)ukh;
|
|
KASSERT((va & PAGE_MASK) == 0);
|
|
vm_map_lock(map);
|
|
uvm_unmap_remove(map, va, va + PAGE_SIZE, &deadentry, NULL, 0);
|
|
KASSERT(deadentry->flags & UVM_MAP_KERNEL);
|
|
KASSERT(deadentry->flags & UVM_MAP_KMAPENT);
|
|
KASSERT(deadentry->next == NULL);
|
|
KASSERT(deadentry == &ukh->ukh_entries[0]);
|
|
|
|
/*
|
|
* unmap the page from pmap and free it.
|
|
*/
|
|
|
|
pmap = vm_map_pmap(map);
|
|
KASSERT(pmap == pmap_kernel());
|
|
if (!pmap_extract(pmap, va, &pa))
|
|
panic("%s: no mapping", __func__);
|
|
pmap_kremove(va, PAGE_SIZE);
|
|
vm_map_unlock(map);
|
|
pg = PHYS_TO_VM_PAGE(pa);
|
|
uvm_pagefree(pg);
|
|
UVMMAP_EVCNT_INCR(ukh_free);
|
|
}
|
|
|
|
static vsize_t
|
|
uvm_kmapent_overhead(vsize_t size)
|
|
{
|
|
|
|
/*
|
|
* - the max number of unmerged entries is howmany(size, PAGE_SIZE)
|
|
* as the min allocation unit is PAGE_SIZE.
|
|
* - UVM_KMAPENT_CHUNK "kmapent"s are allocated from a page.
|
|
* one of them are used to map the page itself.
|
|
*/
|
|
|
|
return howmany(howmany(size, PAGE_SIZE), (UVM_KMAPENT_CHUNK - 1)) *
|
|
PAGE_SIZE;
|
|
}
|
|
|
|
/*
|
|
* map entry reservation
|
|
*/
|
|
|
|
/*
|
|
* uvm_mapent_reserve: reserve map entries for clipping before locking map.
|
|
*
|
|
* => needed when unmapping entries allocated without UVM_FLAG_QUANTUM.
|
|
* => caller shouldn't hold map locked.
|
|
*/
|
|
int
|
|
uvm_mapent_reserve(struct vm_map *map, struct uvm_mapent_reservation *umr,
|
|
int nentries, int flags)
|
|
{
|
|
|
|
umr->umr_nentries = 0;
|
|
|
|
if ((flags & UVM_FLAG_QUANTUM) != 0)
|
|
return 0;
|
|
|
|
if (!VM_MAP_USE_KMAPENT(map))
|
|
return 0;
|
|
|
|
while (nentries--) {
|
|
struct vm_map_entry *ent;
|
|
ent = uvm_kmapent_alloc(map, flags);
|
|
if (!ent) {
|
|
uvm_mapent_unreserve(map, umr);
|
|
return ENOMEM;
|
|
}
|
|
UMR_PUTENTRY(umr, ent);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_unreserve:
|
|
*
|
|
* => caller shouldn't hold map locked.
|
|
* => never fail or sleep.
|
|
*/
|
|
void
|
|
uvm_mapent_unreserve(struct vm_map *map, struct uvm_mapent_reservation *umr)
|
|
{
|
|
|
|
while (!UMR_EMPTY(umr))
|
|
uvm_kmapent_free(UMR_GETENTRY(umr));
|
|
}
|
|
|
|
/*
|
|
* uvm_mapent_trymerge: try to merge an entry with its neighbors.
|
|
*
|
|
* => called with map locked.
|
|
* => return non zero if successfully merged.
|
|
*/
|
|
|
|
int
|
|
uvm_mapent_trymerge(struct vm_map *map, struct vm_map_entry *entry, int flags)
|
|
{
|
|
struct uvm_object *uobj;
|
|
struct vm_map_entry *next;
|
|
struct vm_map_entry *prev;
|
|
vsize_t size;
|
|
int merged = 0;
|
|
bool copying;
|
|
int newetype;
|
|
|
|
if (VM_MAP_USE_KMAPENT(map)) {
|
|
return 0;
|
|
}
|
|
if (entry->aref.ar_amap != NULL) {
|
|
return 0;
|
|
}
|
|
if ((entry->flags & UVM_MAP_NOMERGE) != 0) {
|
|
return 0;
|
|
}
|
|
|
|
uobj = entry->object.uvm_obj;
|
|
size = entry->end - entry->start;
|
|
copying = (flags & UVM_MERGE_COPYING) != 0;
|
|
newetype = copying ? (entry->etype & ~UVM_ET_NEEDSCOPY) : entry->etype;
|
|
|
|
next = entry->next;
|
|
if (next != &map->header &&
|
|
next->start == entry->end &&
|
|
((copying && next->aref.ar_amap != NULL &&
|
|
amap_refs(next->aref.ar_amap) == 1) ||
|
|
(!copying && next->aref.ar_amap == NULL)) &&
|
|
UVM_ET_ISCOMPATIBLE(next, newetype,
|
|
uobj, entry->flags, entry->protection,
|
|
entry->max_protection, entry->inheritance, entry->advice,
|
|
entry->wired_count) &&
|
|
(uobj == NULL || entry->offset + size == next->offset)) {
|
|
int error;
|
|
|
|
if (copying) {
|
|
error = amap_extend(next, size,
|
|
AMAP_EXTEND_NOWAIT|AMAP_EXTEND_BACKWARDS);
|
|
} else {
|
|
error = 0;
|
|
}
|
|
if (error == 0) {
|
|
if (uobj) {
|
|
if (uobj->pgops->pgo_detach) {
|
|
uobj->pgops->pgo_detach(uobj);
|
|
}
|
|
}
|
|
|
|
entry->end = next->end;
|
|
clear_hints(map, next);
|
|
uvm_map_entry_unlink(map, next);
|
|
if (copying) {
|
|
entry->aref = next->aref;
|
|
entry->etype &= ~UVM_ET_NEEDSCOPY;
|
|
}
|
|
uvm_map_check(map, "trymerge forwardmerge");
|
|
uvm_mapent_free_merged(map, next);
|
|
merged++;
|
|
}
|
|
}
|
|
|
|
prev = entry->prev;
|
|
if (prev != &map->header &&
|
|
prev->end == entry->start &&
|
|
((copying && !merged && prev->aref.ar_amap != NULL &&
|
|
amap_refs(prev->aref.ar_amap) == 1) ||
|
|
(!copying && prev->aref.ar_amap == NULL)) &&
|
|
UVM_ET_ISCOMPATIBLE(prev, newetype,
|
|
uobj, entry->flags, entry->protection,
|
|
entry->max_protection, entry->inheritance, entry->advice,
|
|
entry->wired_count) &&
|
|
(uobj == NULL ||
|
|
prev->offset + prev->end - prev->start == entry->offset)) {
|
|
int error;
|
|
|
|
if (copying) {
|
|
error = amap_extend(prev, size,
|
|
AMAP_EXTEND_NOWAIT|AMAP_EXTEND_FORWARDS);
|
|
} else {
|
|
error = 0;
|
|
}
|
|
if (error == 0) {
|
|
if (uobj) {
|
|
if (uobj->pgops->pgo_detach) {
|
|
uobj->pgops->pgo_detach(uobj);
|
|
}
|
|
entry->offset = prev->offset;
|
|
}
|
|
|
|
entry->start = prev->start;
|
|
clear_hints(map, prev);
|
|
uvm_map_entry_unlink(map, prev);
|
|
if (copying) {
|
|
entry->aref = prev->aref;
|
|
entry->etype &= ~UVM_ET_NEEDSCOPY;
|
|
}
|
|
uvm_map_check(map, "trymerge backmerge");
|
|
uvm_mapent_free_merged(map, prev);
|
|
merged++;
|
|
}
|
|
}
|
|
|
|
return merged;
|
|
}
|
|
|
|
#if defined(DDB)
|
|
|
|
/*
|
|
* DDB hooks
|
|
*/
|
|
|
|
/*
|
|
* uvm_map_printit: actually prints the map
|
|
*/
|
|
|
|
void
|
|
uvm_map_printit(struct vm_map *map, bool full,
|
|
void (*pr)(const char *, ...))
|
|
{
|
|
struct vm_map_entry *entry;
|
|
|
|
(*pr)("MAP %p: [0x%lx->0x%lx]\n", map, vm_map_min(map),
|
|
vm_map_max(map));
|
|
(*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=0x%x\n",
|
|
map->nentries, map->size, map->ref_count, map->timestamp,
|
|
map->flags);
|
|
(*pr)("\tpmap=%p(resident=%ld, wired=%ld)\n", map->pmap,
|
|
pmap_resident_count(map->pmap), pmap_wired_count(map->pmap));
|
|
if (!full)
|
|
return;
|
|
for (entry = map->header.next; entry != &map->header;
|
|
entry = entry->next) {
|
|
(*pr)(" - %p: 0x%lx->0x%lx: obj=%p/0x%llx, amap=%p/%d\n",
|
|
entry, entry->start, entry->end, entry->object.uvm_obj,
|
|
(long long)entry->offset, entry->aref.ar_amap,
|
|
entry->aref.ar_pageoff);
|
|
(*pr)(
|
|
"\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, "
|
|
"wc=%d, adv=%d\n",
|
|
(entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F',
|
|
(entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F',
|
|
(entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F',
|
|
entry->protection, entry->max_protection,
|
|
entry->inheritance, entry->wired_count, entry->advice);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_object_printit: actually prints the object
|
|
*/
|
|
|
|
void
|
|
uvm_object_printit(struct uvm_object *uobj, bool full,
|
|
void (*pr)(const char *, ...))
|
|
{
|
|
struct vm_page *pg;
|
|
int cnt = 0;
|
|
|
|
(*pr)("OBJECT %p: locked=%d, pgops=%p, npages=%d, ",
|
|
uobj, uobj->vmobjlock.lock_data, uobj->pgops, uobj->uo_npages);
|
|
if (UVM_OBJ_IS_KERN_OBJECT(uobj))
|
|
(*pr)("refs=<SYSTEM>\n");
|
|
else
|
|
(*pr)("refs=%d\n", uobj->uo_refs);
|
|
|
|
if (!full) {
|
|
return;
|
|
}
|
|
(*pr)(" PAGES <pg,offset>:\n ");
|
|
TAILQ_FOREACH(pg, &uobj->memq, listq) {
|
|
cnt++;
|
|
(*pr)("<%p,0x%llx> ", pg, (long long)pg->offset);
|
|
if ((cnt % 3) == 0) {
|
|
(*pr)("\n ");
|
|
}
|
|
}
|
|
if ((cnt % 3) != 0) {
|
|
(*pr)("\n");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_page_printit: actually print the page
|
|
*/
|
|
|
|
static const char page_flagbits[] = UVM_PGFLAGBITS;
|
|
static const char page_pqflagbits[] = UVM_PQFLAGBITS;
|
|
|
|
void
|
|
uvm_page_printit(struct vm_page *pg, bool full,
|
|
void (*pr)(const char *, ...))
|
|
{
|
|
struct vm_page *tpg;
|
|
struct uvm_object *uobj;
|
|
struct pglist *pgl;
|
|
char pgbuf[128];
|
|
char pqbuf[128];
|
|
|
|
(*pr)("PAGE %p:\n", pg);
|
|
bitmask_snprintf(pg->flags, page_flagbits, pgbuf, sizeof(pgbuf));
|
|
bitmask_snprintf(pg->pqflags, page_pqflagbits, pqbuf, sizeof(pqbuf));
|
|
(*pr)(" flags=%s, pqflags=%s, wire_count=%d, pa=0x%lx\n",
|
|
pgbuf, pqbuf, pg->wire_count, (long)VM_PAGE_TO_PHYS(pg));
|
|
(*pr)(" uobject=%p, uanon=%p, offset=0x%llx loan_count=%d\n",
|
|
pg->uobject, pg->uanon, (long long)pg->offset, pg->loan_count);
|
|
#if defined(UVM_PAGE_TRKOWN)
|
|
if (pg->flags & PG_BUSY)
|
|
(*pr)(" owning process = %d, tag=%s\n",
|
|
pg->owner, pg->owner_tag);
|
|
else
|
|
(*pr)(" page not busy, no owner\n");
|
|
#else
|
|
(*pr)(" [page ownership tracking disabled]\n");
|
|
#endif
|
|
|
|
if (!full)
|
|
return;
|
|
|
|
/* cross-verify object/anon */
|
|
if ((pg->pqflags & PQ_FREE) == 0) {
|
|
if (pg->pqflags & PQ_ANON) {
|
|
if (pg->uanon == NULL || pg->uanon->an_page != pg)
|
|
(*pr)(" >>> ANON DOES NOT POINT HERE <<< (%p)\n",
|
|
(pg->uanon) ? pg->uanon->an_page : NULL);
|
|
else
|
|
(*pr)(" anon backpointer is OK\n");
|
|
} else {
|
|
uobj = pg->uobject;
|
|
if (uobj) {
|
|
(*pr)(" checking object list\n");
|
|
TAILQ_FOREACH(tpg, &uobj->memq, listq) {
|
|
if (tpg == pg) {
|
|
break;
|
|
}
|
|
}
|
|
if (tpg)
|
|
(*pr)(" page found on object list\n");
|
|
else
|
|
(*pr)(" >>> PAGE NOT FOUND ON OBJECT LIST! <<<\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
/* cross-verify page queue */
|
|
if (pg->pqflags & PQ_FREE) {
|
|
int fl = uvm_page_lookup_freelist(pg);
|
|
int color = VM_PGCOLOR_BUCKET(pg);
|
|
pgl = &uvm.page_free[fl].pgfl_buckets[color].pgfl_queues[
|
|
((pg)->flags & PG_ZERO) ? PGFL_ZEROS : PGFL_UNKNOWN];
|
|
} else {
|
|
pgl = NULL;
|
|
}
|
|
|
|
if (pgl) {
|
|
(*pr)(" checking pageq list\n");
|
|
TAILQ_FOREACH(tpg, pgl, pageq) {
|
|
if (tpg == pg) {
|
|
break;
|
|
}
|
|
}
|
|
if (tpg)
|
|
(*pr)(" page found on pageq list\n");
|
|
else
|
|
(*pr)(" >>> PAGE NOT FOUND ON PAGEQ LIST! <<<\n");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_pages_printthem - print a summary of all managed pages
|
|
*/
|
|
|
|
void
|
|
uvm_page_printall(void (*pr)(const char *, ...))
|
|
{
|
|
unsigned i;
|
|
struct vm_page *pg;
|
|
|
|
(*pr)("%18s %4s %4s %18s %18s"
|
|
#ifdef UVM_PAGE_TRKOWN
|
|
" OWNER"
|
|
#endif
|
|
"\n", "PAGE", "FLAG", "PQ", "UOBJECT", "UANON");
|
|
for (i = 0; i < vm_nphysseg; i++) {
|
|
for (pg = vm_physmem[i].pgs; pg <= vm_physmem[i].lastpg; pg++) {
|
|
(*pr)("%18p %04x %04x %18p %18p",
|
|
pg, pg->flags, pg->pqflags, pg->uobject,
|
|
pg->uanon);
|
|
#ifdef UVM_PAGE_TRKOWN
|
|
if (pg->flags & PG_BUSY)
|
|
(*pr)(" %d [%s]", pg->owner, pg->owner_tag);
|
|
#endif
|
|
(*pr)("\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* uvm_map_create: create map
|
|
*/
|
|
|
|
struct vm_map *
|
|
uvm_map_create(pmap_t pmap, vaddr_t vmin, vaddr_t vmax, int flags)
|
|
{
|
|
struct vm_map *result;
|
|
|
|
MALLOC(result, struct vm_map *, sizeof(struct vm_map),
|
|
M_VMMAP, M_WAITOK);
|
|
uvm_map_setup(result, vmin, vmax, flags);
|
|
result->pmap = pmap;
|
|
return(result);
|
|
}
|
|
|
|
/*
|
|
* uvm_map_setup: init map
|
|
*
|
|
* => map must not be in service yet.
|
|
*/
|
|
|
|
void
|
|
uvm_map_setup(struct vm_map *map, vaddr_t vmin, vaddr_t vmax, int flags)
|
|
{
|
|
int ipl;
|
|
|
|
RB_INIT(&map->rbhead);
|
|
map->header.next = map->header.prev = &map->header;
|
|
map->nentries = 0;
|
|
map->size = 0;
|
|
map->ref_count = 1;
|
|
vm_map_setmin(map, vmin);
|
|
vm_map_setmax(map, vmax);
|
|
map->flags = flags;
|
|
map->first_free = &map->header;
|
|
map->hint = &map->header;
|
|
map->timestamp = 0;
|
|
map->busy = NULL;
|
|
|
|
if ((flags & VM_MAP_INTRSAFE) != 0) {
|
|
ipl = IPL_VM;
|
|
} else {
|
|
ipl = IPL_NONE;
|
|
}
|
|
|
|
rw_init(&map->lock);
|
|
cv_init(&map->cv, "vm_map");
|
|
mutex_init(&map->misc_lock, MUTEX_DRIVER, ipl);
|
|
mutex_init(&map->mutex, MUTEX_DRIVER, ipl);
|
|
|
|
/*
|
|
* The hint lock can get acquired with the pagequeue
|
|
* lock held, so must be at IPL_VM.
|
|
*/
|
|
mutex_init(&map->hint_lock, MUTEX_DRIVER, IPL_VM);
|
|
}
|
|
|
|
|
|
/*
|
|
* U N M A P - m a i n e n t r y p o i n t
|
|
*/
|
|
|
|
/*
|
|
* uvm_unmap1: remove mappings from a vm_map (from "start" up to "stop")
|
|
*
|
|
* => caller must check alignment and size
|
|
* => map must be unlocked (we will lock it)
|
|
* => flags is UVM_FLAG_QUANTUM or 0.
|
|
*/
|
|
|
|
void
|
|
uvm_unmap1(struct vm_map *map, vaddr_t start, vaddr_t end, int flags)
|
|
{
|
|
struct vm_map_entry *dead_entries;
|
|
struct uvm_mapent_reservation umr;
|
|
UVMHIST_FUNC("uvm_unmap"); UVMHIST_CALLED(maphist);
|
|
|
|
UVMHIST_LOG(maphist, " (map=0x%x, start=0x%x, end=0x%x)",
|
|
map, start, end, 0);
|
|
/*
|
|
* work now done by helper functions. wipe the pmap's and then
|
|
* detach from the dead entries...
|
|
*/
|
|
uvm_mapent_reserve(map, &umr, 2, flags);
|
|
vm_map_lock(map);
|
|
uvm_unmap_remove(map, start, end, &dead_entries, &umr, flags);
|
|
vm_map_unlock(map);
|
|
uvm_mapent_unreserve(map, &umr);
|
|
|
|
if (dead_entries != NULL)
|
|
uvm_unmap_detach(dead_entries, 0);
|
|
|
|
UVMHIST_LOG(maphist, "<- done", 0,0,0,0);
|
|
}
|
|
|
|
|
|
/*
|
|
* uvm_map_reference: add reference to a map
|
|
*
|
|
* => map need not be locked (we use misc_lock).
|
|
*/
|
|
|
|
void
|
|
uvm_map_reference(struct vm_map *map)
|
|
{
|
|
mutex_enter(&map->misc_lock);
|
|
map->ref_count++;
|
|
mutex_exit(&map->misc_lock);
|
|
}
|
|
|
|
struct vm_map_kernel *
|
|
vm_map_to_kernel(struct vm_map *map)
|
|
{
|
|
|
|
KASSERT(VM_MAP_IS_KERNEL(map));
|
|
|
|
return (struct vm_map_kernel *)map;
|
|
}
|
|
|
|
bool
|
|
vm_map_starved_p(struct vm_map *map)
|
|
{
|
|
|
|
if ((map->flags & VM_MAP_WANTVA) != 0) {
|
|
return true;
|
|
}
|
|
/* XXX */
|
|
if ((vm_map_max(map) - vm_map_min(map)) / 16 * 15 < map->size) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|