/* $NetBSD: uvm_map.h,v 1.80 2020/05/26 00:50:53 kamil Exp $ */ /* * Copyright (c) 1997 Charles D. Cranor and Washington University. * Copyright (c) 1991, 1993, The Regents of the University of California. * * All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)vm_map.h 8.3 (Berkeley) 3/15/94 * from: Id: uvm_map.h,v 1.1.2.3 1998/02/07 01:16:55 chs Exp * * * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ #ifndef _UVM_UVM_MAP_H_ #define _UVM_UVM_MAP_H_ /* * uvm_map.h */ #ifdef _KERNEL /* * macros */ /* * UVM_MAP_CLIP_START: ensure that the entry begins at or after * the starting address, if it doesn't we split the entry. * * => map must be locked by caller */ #define UVM_MAP_CLIP_START(MAP,ENTRY,VA) { \ if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \ uvm_map_clip_start(MAP,ENTRY,VA); \ } \ } /* * UVM_MAP_CLIP_END: ensure that the entry ends at or before * the ending address, if it does't we split the entry. * * => map must be locked by caller */ #define UVM_MAP_CLIP_END(MAP,ENTRY,VA) { \ if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \ uvm_map_clip_end(MAP,ENTRY,VA); \ } \ } /* * extract flags */ #define UVM_EXTRACT_REMOVE 0x01 /* remove mapping from old map */ #define UVM_EXTRACT_CONTIG 0x02 /* try to keep it contig */ #define UVM_EXTRACT_QREF 0x04 /* use quick refs */ #define UVM_EXTRACT_FIXPROT 0x08 /* set prot to maxprot as we go */ #define UVM_EXTRACT_RESERVED 0x10 /* caller did uvm_map_reserve() */ #define UVM_EXTRACT_PROT_ALL 0x20 /* set prot to UVM_PROT_ALL */ #endif /* _KERNEL */ #include #include #include #include #include #include /* * Address map entries consist of start and end addresses, * a VM object (or sharing map) and offset into that object, * and user-exported inheritance and protection information. * Also included is control information for virtual copy operations. * * At runtime this is aligned on a cacheline boundary, with fields * used during fault processing to do RB tree lookup clustered at * the beginning. */ struct vm_map_entry { struct rb_node rb_node; /* tree information */ vaddr_t start; /* start address */ vaddr_t end; /* end address */ vsize_t gap; /* free space after */ vsize_t maxgap; /* space in subtree */ struct vm_map_entry *prev; /* previous entry */ struct vm_map_entry *next; /* next entry */ union { struct uvm_object *uvm_obj; /* uvm object */ struct vm_map *sub_map; /* belongs to another map */ } object; /* object I point to */ voff_t offset; /* offset into object */ uint8_t etype; /* entry type */ uint8_t flags; /* flags */ uint8_t advice; /* madvise advice */ uint8_t unused; /* unused */ vm_prot_t protection; /* protection code */ vm_prot_t max_protection; /* maximum protection */ vm_inherit_t inheritance; /* inheritance */ int wired_count; /* can be paged if == 0 */ struct vm_aref aref; /* anonymous overlay */ }; /* flags */ #define UVM_MAP_KERNEL 0x01 /* kernel map entry */ #define UVM_MAP_STATIC 0x04 /* special static entries */ #define UVM_MAP_NOMERGE 0x08 /* this entry is not mergable */ #define VM_MAPENT_ISWIRED(entry) ((entry)->wired_count != 0) /* * Maps are doubly-linked lists of map entries, kept sorted * by address. A single hint is provided to start * searches again from the last successful search, * insertion, or removal. * * LOCKING PROTOCOL NOTES: * ----------------------- * * VM map locking is a little complicated. There are both shared * and exclusive locks on maps. However, it is sometimes required * to downgrade an exclusive lock to a shared lock, and upgrade to * an exclusive lock again (to perform error recovery). However, * another thread *must not* queue itself to receive an exclusive * lock while before we upgrade back to exclusive, otherwise the * error recovery becomes extremely difficult, if not impossible. * * In order to prevent this scenario, we introduce the notion of * a `busy' map. A `busy' map is read-locked, but other threads * attempting to write-lock wait for this flag to clear before * entering the lock manager. A map may only be marked busy * when the map is write-locked (and then the map must be downgraded * to read-locked), and may only be marked unbusy by the thread * which marked it busy (holding *either* a read-lock or a * write-lock, the latter being gained by an upgrade). * * Access to the map `flags' member is controlled by the `flags_lock' * simple lock. Note that some flags are static (set once at map * creation time, and never changed), and thus require no locking * to check those flags. All flags which are r/w must be set or * cleared while the `flags_lock' is asserted. Additional locking * requirements are: * * VM_MAP_PAGEABLE r/o static flag; no locking required * * VM_MAP_WIREFUTURE r/w; may only be set or cleared when * map is write-locked. may be tested * without asserting `flags_lock'. * * VM_MAP_DYING r/o; set when a vmspace is being * destroyed to indicate that updates * to the pmap can be skipped. * * VM_MAP_TOPDOWN r/o; set when the vmspace is * created if the unspecified map * allocations are to be arranged in * a "top down" manner. */ struct vm_map { struct pmap * pmap; /* Physical map */ krwlock_t lock; /* Non-intrsafe lock */ struct lwp * busy; /* LWP holding map busy */ kmutex_t misc_lock; /* Lock for cv, busy */ kcondvar_t cv; /* For signalling */ int flags; /* flags */ struct rb_tree rb_tree; /* Tree for entries */ struct vm_map_entry header; /* List of entries */ int nentries; /* Number of entries */ vsize_t size; /* virtual size */ volatile int ref_count; /* Reference count */ struct vm_map_entry * hint; /* hint for quick lookups */ struct vm_map_entry * first_free; /* First free space hint */ unsigned int timestamp; /* Version number */ }; #if defined(_KERNEL) #include #endif /* defined(_KERNEL) */ #define VM_MAP_IS_KERNEL(map) (vm_map_pmap(map) == pmap_kernel()) /* vm_map flags */ #define VM_MAP_PAGEABLE 0x01 /* ro: entries are pageable */ #define VM_MAP_WIREFUTURE 0x04 /* rw: wire future mappings */ #define VM_MAP_DYING 0x20 /* rw: map is being destroyed */ #define VM_MAP_TOPDOWN 0x40 /* ro: arrange map top-down */ #define VM_MAP_WANTVA 0x100 /* rw: want va */ #define VM_MAP_BITS "\177\020\ b\0PAGEABLE\0\ b\2WIREFUTURE\0\ b\5DYING\0\ b\6TOPDOWN\0\ b\10WANTVA\0" #ifdef _KERNEL struct uvm_map_args { struct vm_map_entry *uma_prev; vaddr_t uma_start; vsize_t uma_size; struct uvm_object *uma_uobj; voff_t uma_uoffset; uvm_flag_t uma_flags; }; #endif /* _KERNEL */ /* * globals: */ #ifdef _KERNEL #include #ifdef PMAP_GROWKERNEL extern vaddr_t uvm_maxkaddr; #endif /* * protos: the following prototypes define the interface to vm_map */ void uvm_map_deallocate(struct vm_map *); int uvm_map_willneed(struct vm_map *, vaddr_t, vaddr_t); int uvm_map_clean(struct vm_map *, vaddr_t, vaddr_t, int); void uvm_map_clip_start(struct vm_map *, struct vm_map_entry *, vaddr_t); void uvm_map_clip_end(struct vm_map *, struct vm_map_entry *, vaddr_t); int uvm_map_extract(struct vm_map *, vaddr_t, vsize_t, struct vm_map *, vaddr_t *, int); struct vm_map_entry * uvm_map_findspace(struct vm_map *, vaddr_t, vsize_t, vaddr_t *, struct uvm_object *, voff_t, vsize_t, int); int uvm_map_inherit(struct vm_map *, vaddr_t, vaddr_t, vm_inherit_t); int uvm_map_advice(struct vm_map *, vaddr_t, vaddr_t, int); void uvm_map_init(void); void uvm_map_init_caches(void); bool uvm_map_lookup_entry(struct vm_map *, vaddr_t, struct vm_map_entry **); void uvm_map_reference(struct vm_map *); int uvm_map_reserve(struct vm_map *, vsize_t, vaddr_t, vsize_t, vaddr_t *, uvm_flag_t); void uvm_map_setup(struct vm_map *, vaddr_t, vaddr_t, int); int uvm_map_submap(struct vm_map *, vaddr_t, vaddr_t, struct vm_map *); void uvm_unmap1(struct vm_map *, vaddr_t, vaddr_t, int); #define uvm_unmap(map, s, e) uvm_unmap1((map), (s), (e), 0) void uvm_unmap_detach(struct vm_map_entry *,int); void uvm_unmap_remove(struct vm_map *, vaddr_t, vaddr_t, struct vm_map_entry **, int); int uvm_map_prepare(struct vm_map *, vaddr_t, vsize_t, struct uvm_object *, voff_t, vsize_t, uvm_flag_t, struct uvm_map_args *); int uvm_map_enter(struct vm_map *, const struct uvm_map_args *, struct vm_map_entry *); int uvm_mapent_trymerge(struct vm_map *, struct vm_map_entry *, int); #define UVM_MERGE_COPYING 1 /* * VM map locking operations. */ bool vm_map_lock_try(struct vm_map *); void vm_map_lock(struct vm_map *); void vm_map_unlock(struct vm_map *); void vm_map_unbusy(struct vm_map *); void vm_map_lock_read(struct vm_map *); void vm_map_unlock_read(struct vm_map *); void vm_map_busy(struct vm_map *); bool vm_map_locked_p(struct vm_map *); void uvm_map_lock_entry(struct vm_map_entry *, krw_t); void uvm_map_unlock_entry(struct vm_map_entry *); #endif /* _KERNEL */ /* * Functions implemented as macros */ #define vm_map_min(map) ((map)->header.end) #define vm_map_max(map) ((map)->header.start) #define vm_map_setmin(map, v) ((map)->header.end = (v)) #define vm_map_setmax(map, v) ((map)->header.start = (v)) #define vm_map_pmap(map) ((map)->pmap) #endif /* _UVM_UVM_MAP_H_ */