| 1 | /* $NetBSD: extent.h,v 1.19 2012/01/27 18:53:10 para Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1996, 1998 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Jason R. Thorpe. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | #ifndef _SYS_EXTENT_H_ |
| 33 | #define _SYS_EXTENT_H_ |
| 34 | |
| 35 | #include <sys/queue.h> |
| 36 | #include <sys/mutex.h> |
| 37 | #include <sys/condvar.h> |
| 38 | |
| 39 | struct extent_region { |
| 40 | LIST_ENTRY(extent_region) er_link; /* link in region list */ |
| 41 | u_long er_start; /* start of region */ |
| 42 | u_long er_end; /* end of region */ |
| 43 | int er_flags; /* misc. flags */ |
| 44 | }; |
| 45 | |
| 46 | /* er_flags */ |
| 47 | #define ER_ALLOC 0x01 /* region descriptor dynamically allocated */ |
| 48 | |
| 49 | struct extent { |
| 50 | const char *ex_name; /* name of extent */ |
| 51 | kmutex_t ex_lock; /* lock on this extent */ |
| 52 | kcondvar_t ex_cv; /* synchronization */ |
| 53 | /* allocated regions in extent */ |
| 54 | LIST_HEAD(, extent_region) ex_regions; |
| 55 | u_long ex_start; /* start of extent */ |
| 56 | u_long ex_end; /* end of extent */ |
| 57 | int ex_flags; /* misc. information */ |
| 58 | }; |
| 59 | |
| 60 | struct extent_fixed { |
| 61 | struct extent fex_extent; /* MUST BE FIRST */ |
| 62 | /* freelist of region descriptors */ |
| 63 | LIST_HEAD(, extent_region) fex_freelist; |
| 64 | void * fex_storage; /* storage space for descriptors */ |
| 65 | size_t fex_storagesize; /* size of storage space */ |
| 66 | }; |
| 67 | |
| 68 | /* ex_flags; for internal use only */ |
| 69 | #define EXF_FIXED 0x01 /* extent uses fixed storage */ |
| 70 | #define EXF_NOCOALESCE 0x02 /* coalescing of regions not allowed */ |
| 71 | #define EXF_FLWANTED 0x08 /* someone asleep on freelist */ |
| 72 | |
| 73 | #define EXF_BITS "\20\4FLWANTED\2NOCOALESCE\1FIXED" |
| 74 | |
| 75 | /* misc. flags passed to extent functions */ |
| 76 | #define EX_NOWAIT 0x00 /* not safe to sleep */ |
| 77 | #define EX_WAITOK 0x01 /* safe to sleep */ |
| 78 | #define EX_FAST 0x02 /* take first fit in extent_alloc() */ |
| 79 | #define EX_CATCH 0x04 /* catch signals while sleeping */ |
| 80 | #define EX_NOCOALESCE 0x08 /* create a non-coalescing extent */ |
| 81 | #define EX_MALLOCOK 0x10 /* safe to call kmem_alloc() */ |
| 82 | #define EX_WAITSPACE 0x20 /* wait for space to become free */ |
| 83 | #define EX_BOUNDZERO 0x40 /* boundary lines start at 0 */ |
| 84 | |
| 85 | /* |
| 86 | * Special place holders for "alignment" and "boundary" arguments, |
| 87 | * in the event the caller doesn't wish to use those features. |
| 88 | */ |
| 89 | #define EX_NOALIGN 1 /* don't do alignment */ |
| 90 | #define EX_NOBOUNDARY 0 /* don't do boundary checking */ |
| 91 | |
| 92 | #if defined(_KERNEL) || defined(_EXTENT_TESTING) |
| 93 | #define EXTENT_FIXED_STORAGE_SIZE(_nregions) \ |
| 94 | (ALIGN(sizeof(struct extent_fixed)) + \ |
| 95 | ((ALIGN(sizeof(struct extent_region))) * \ |
| 96 | (_nregions))) |
| 97 | |
| 98 | struct extent *extent_create(const char *, u_long, u_long, |
| 99 | void *, size_t, int); |
| 100 | void extent_destroy(struct extent *); |
| 101 | int extent_alloc_subregion1(struct extent *, u_long, u_long, |
| 102 | u_long, u_long, u_long, u_long, int, u_long *); |
| 103 | int extent_alloc_subregion(struct extent *, u_long, u_long, |
| 104 | u_long, u_long, u_long, int, u_long *); |
| 105 | int extent_alloc_region(struct extent *, u_long, u_long, int); |
| 106 | int extent_alloc1(struct extent *, u_long, u_long, u_long, u_long, int, |
| 107 | u_long *); |
| 108 | int extent_alloc(struct extent *, u_long, u_long, u_long, int, u_long *); |
| 109 | int extent_free(struct extent *, u_long, u_long, int); |
| 110 | void extent_print(struct extent *); |
| 111 | void extent_init(void); |
| 112 | |
| 113 | #endif /* _KERNEL || _EXTENT_TESTING */ |
| 114 | |
| 115 | #endif /* ! _SYS_EXTENT_H_ */ |
| 116 | |