1 /* $NetBSD: extent.h,v 1.26 2017/08/24 11:33:28 jmcneill 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 #ifndef _KERNEL 40 #include <stdbool.h> 41 #endif 42 43 struct extent_region { 44 LIST_ENTRY(extent_region) er_link; /* link in region list */ 45 u_long er_start; /* start of region */ 46 u_long er_end; /* end of region */ 47 int er_flags; /* misc. flags */ 48 }; 49 50 /* er_flags */ 51 #define ER_ALLOC 0x01 /* region descriptor dynamically allocated */ 52 53 struct extent { 54 const char *ex_name; /* name of extent */ 55 kmutex_t ex_lock; /* lock on this extent */ 56 kcondvar_t ex_cv; /* synchronization */ 57 /* allocated regions in extent */ 58 LIST_HEAD(, extent_region) ex_regions; 59 u_long ex_start; /* start of extent */ 60 u_long ex_end; /* end of extent */ 61 int ex_flags; /* misc. information */ 62 bool ex_flwanted; /* someone asleep on freelist */ 63 }; 64 65 struct extent_fixed { 66 struct extent fex_extent; /* MUST BE FIRST */ 67 /* freelist of region descriptors */ 68 LIST_HEAD(, extent_region) fex_freelist; 69 void * fex_storage; /* storage space for descriptors */ 70 size_t fex_storagesize; /* size of storage space */ 71 }; 72 73 /* ex_flags; for internal use only */ 74 #define EXF_FIXED __BIT(0) /* extent uses fixed storage */ 75 #define EXF_NOCOALESCE __BIT(1) /* coalescing of regions not allowed */ 76 #define EXF_EARLY __BIT(2) /* no need to lock */ 77 78 #define EXF_BITS "\20\3EARLY\2NOCOALESCE\1FIXED" 79 80 /* misc. flags passed to extent functions */ 81 #define EX_NOWAIT 0 /* not safe to sleep */ 82 #define EX_WAITOK __BIT(0) /* safe to sleep */ 83 #define EX_FAST __BIT(1) /* take first fit in extent_alloc() */ 84 #define EX_CATCH __BIT(2) /* catch signals while sleeping */ 85 #define EX_NOCOALESCE __BIT(3) /* create a non-coalescing extent */ 86 #define EX_MALLOCOK __BIT(4) /* safe to call kmem_alloc() */ 87 #define EX_WAITSPACE __BIT(5) /* wait for space to become free */ 88 #define EX_BOUNDZERO __BIT(6) /* boundary lines start at 0 */ 89 #define EX_EARLY __BIT(7) /* safe for early kernel bootstrap */ 90 91 /* 92 * Special place holders for "alignment" and "boundary" arguments, 93 * in the event the caller doesn't wish to use those features. 94 */ 95 #define EX_NOALIGN 1 /* don't do alignment */ 96 #define EX_NOBOUNDARY 0 /* don't do boundary checking */ 97 98 #if defined(_KERNEL) || defined(_EXTENT_TESTING) 99 #define EXTENT_FIXED_STORAGE_SIZE(_nregions) \ 100 (ALIGN(sizeof(struct extent_fixed)) + \ 101 ((ALIGN(sizeof(struct extent_region))) * \ 102 (_nregions))) 103 104 struct extent *extent_create(const char *, u_long, u_long, 105 void *, size_t, int); 106 void extent_destroy(struct extent *); 107 int extent_alloc_subregion1(struct extent *, u_long, u_long, 108 u_long, u_long, u_long, u_long, int, u_long *); 109 int extent_alloc_subregion(struct extent *, u_long, u_long, 110 u_long, u_long, u_long, int, u_long *); 111 int extent_alloc_region(struct extent *, u_long, u_long, int); 112 int extent_alloc1(struct extent *, u_long, u_long, u_long, u_long, int, 113 u_long *); 114 int extent_alloc(struct extent *, u_long, u_long, u_long, int, u_long *); 115 int extent_free(struct extent *, u_long, u_long, int); 116 void extent_print(struct extent *); 117 void extent_init(void); 118 119 #endif /* _KERNEL || _EXTENT_TESTING */ 120 121 #endif /* ! _SYS_EXTENT_H_ */ 122