1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 #ifndef _LINUX_IDR_H_ 32 #define _LINUX_IDR_H_ 33 34 #include <sys/param.h> 35 #include <sys/lock.h> 36 #include <sys/mutex.h> 37 38 #include <linux/types.h> 39 40 #define IDR_BITS 5 41 #define IDR_SIZE (1 << IDR_BITS) 42 #define IDR_MASK (IDR_SIZE - 1) 43 44 #define MAX_ID_SHIFT ((sizeof(int) * NBBY) - 1) 45 #define MAX_ID_BIT (1U << MAX_ID_SHIFT) 46 #define MAX_ID_MASK (MAX_ID_BIT - 1) 47 #define MAX_LEVEL (MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS 48 49 #define MAX_IDR_SHIFT (sizeof(int)*8 - 1) 50 #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT) 51 #define MAX_IDR_MASK (MAX_IDR_BIT - 1) 52 53 struct idr_layer { 54 unsigned long bitmap; 55 struct idr_layer *ary[IDR_SIZE]; 56 }; 57 58 struct idr { 59 struct mtx lock; 60 struct idr_layer *top; 61 struct idr_layer *free; 62 int layers; 63 int next_cyclic_id; 64 }; 65 66 /* NOTE: It is the applications responsibility to destroy the IDR */ 67 #define DEFINE_IDR(name) \ 68 struct idr name; \ 69 SYSINIT(name##_idr_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST, \ 70 idr_init, &(name)) 71 72 /* NOTE: It is the applications responsibility to destroy the IDA */ 73 #define DEFINE_IDA(name) \ 74 struct ida name; \ 75 SYSINIT(name##_ida_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST, \ 76 ida_init, &(name)) 77 78 void idr_preload(gfp_t gfp_mask); 79 void idr_preload_end(void); 80 void *idr_find(struct idr *idp, int id); 81 void *idr_get_next(struct idr *idp, int *nextid); 82 bool idr_is_empty(struct idr *idp); 83 int idr_pre_get(struct idr *idp, gfp_t gfp_mask); 84 int idr_get_new(struct idr *idp, void *ptr, int *id); 85 int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id); 86 void *idr_replace(struct idr *idp, void *ptr, int id); 87 void *idr_remove(struct idr *idp, int id); 88 void idr_remove_all(struct idr *idp); 89 void idr_destroy(struct idr *idp); 90 void idr_init(struct idr *idp); 91 int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t); 92 int idr_alloc_cyclic(struct idr *idp, void *ptr, int start, int end, gfp_t); 93 int idr_for_each(struct idr *idp, int (*fn)(int id, void *p, void *data), void *data); 94 95 #define idr_for_each_entry(idp, entry, id) \ 96 for ((id) = 0; ((entry) = idr_get_next(idp, &(id))) != NULL; ++(id)) 97 98 #define IDA_CHUNK_SIZE 128 /* 128 bytes per chunk */ 99 #define IDA_BITMAP_LONGS (IDA_CHUNK_SIZE / sizeof(long) - 1) 100 #define IDA_BITMAP_BITS (IDA_BITMAP_LONGS * sizeof(long) * 8) 101 102 struct ida_bitmap { 103 long nr_busy; 104 unsigned long bitmap[IDA_BITMAP_LONGS]; 105 }; 106 107 struct ida { 108 struct idr idr; 109 struct ida_bitmap *free_bitmap; 110 }; 111 112 int ida_pre_get(struct ida *ida, gfp_t gfp_mask); 113 int ida_get_new_above(struct ida *ida, int starting_id, int *p_id); 114 void ida_remove(struct ida *ida, int id); 115 void ida_destroy(struct ida *ida); 116 void ida_init(struct ida *ida); 117 118 int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end, 119 gfp_t gfp_mask); 120 void ida_simple_remove(struct ida *ida, unsigned int id); 121 122 static inline void 123 ida_free(struct ida *ida, int id) 124 { 125 126 ida_remove(ida, id); 127 } 128 129 static inline int 130 ida_get_new(struct ida *ida, int *p_id) 131 { 132 133 return (ida_get_new_above(ida, 0, p_id)); 134 } 135 136 static inline int 137 ida_alloc_max(struct ida *ida, unsigned int max, gfp_t gfp) 138 { 139 140 return (ida_simple_get(ida, 0, max, gfp)); 141 } 142 143 static inline bool 144 ida_is_empty(struct ida *ida) 145 { 146 147 return (idr_is_empty(&ida->idr)); 148 } 149 150 #endif /* _LINUX_IDR_H_ */ 151