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 #ifndef _LINUXKPI_LINUX_IDR_H_ 30 #define _LINUXKPI_LINUX_IDR_H_ 31 32 #include <sys/param.h> 33 #include <sys/lock.h> 34 #include <sys/mutex.h> 35 36 #include <linux/types.h> 37 38 #define IDR_BITS 5 39 #define IDR_SIZE (1 << IDR_BITS) 40 #define IDR_MASK (IDR_SIZE - 1) 41 42 #define MAX_ID_SHIFT ((sizeof(int) * NBBY) - 1) 43 #define MAX_ID_BIT (1U << MAX_ID_SHIFT) 44 #define MAX_ID_MASK (MAX_ID_BIT - 1) 45 #define MAX_LEVEL (MAX_ID_SHIFT + IDR_BITS - 1) / IDR_BITS 46 47 #define MAX_IDR_SHIFT (sizeof(int)*8 - 1) 48 #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT) 49 #define MAX_IDR_MASK (MAX_IDR_BIT - 1) 50 51 struct idr_layer { 52 unsigned long bitmap; 53 struct idr_layer *ary[IDR_SIZE]; 54 }; 55 56 struct idr { 57 struct mtx lock; 58 struct idr_layer *top; 59 struct idr_layer *free; 60 int layers; 61 int next_cyclic_id; 62 }; 63 64 /* NOTE: It is the applications responsibility to destroy the IDR */ 65 #define DEFINE_IDR(name) \ 66 struct idr name; \ 67 SYSINIT(name##_idr_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST, \ 68 idr_init, &(name)) 69 70 /* NOTE: It is the applications responsibility to destroy the IDA */ 71 #define DEFINE_IDA(name) \ 72 struct ida name; \ 73 SYSINIT(name##_ida_sysinit, SI_SUB_DRIVERS, SI_ORDER_FIRST, \ 74 ida_init, &(name)) 75 76 void idr_preload(gfp_t gfp_mask); 77 void idr_preload_end(void); 78 void *idr_find(struct idr *idp, int id); 79 void *idr_get_next(struct idr *idp, int *nextid); 80 bool idr_is_empty(struct idr *idp); 81 int idr_pre_get(struct idr *idp, gfp_t gfp_mask); 82 int idr_get_new(struct idr *idp, void *ptr, int *id); 83 int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id); 84 void *idr_replace(struct idr *idp, void *ptr, int id); 85 void *idr_remove(struct idr *idp, int id); 86 void idr_remove_all(struct idr *idp); 87 void idr_destroy(struct idr *idp); 88 void idr_init(struct idr *idp); 89 int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t); 90 int idr_alloc_cyclic(struct idr *idp, void *ptr, int start, int end, gfp_t); 91 int idr_for_each(struct idr *idp, int (*fn)(int id, void *p, void *data), void *data); 92 93 #define idr_for_each_entry(idp, entry, id) \ 94 for ((id) = 0; ((entry) = idr_get_next(idp, &(id))) != NULL; ++(id)) 95 96 #define IDA_CHUNK_SIZE 128 /* 128 bytes per chunk */ 97 #define IDA_BITMAP_LONGS (IDA_CHUNK_SIZE / sizeof(long) - 1) 98 #define IDA_BITMAP_BITS (IDA_BITMAP_LONGS * sizeof(long) * 8) 99 100 struct ida_bitmap { 101 long nr_busy; 102 unsigned long bitmap[IDA_BITMAP_LONGS]; 103 }; 104 105 struct ida { 106 struct idr idr; 107 struct ida_bitmap *free_bitmap; 108 }; 109 110 int ida_pre_get(struct ida *ida, gfp_t gfp_mask); 111 int ida_get_new_above(struct ida *ida, int starting_id, int *p_id); 112 void ida_remove(struct ida *ida, int id); 113 void ida_destroy(struct ida *ida); 114 void ida_init(struct ida *ida); 115 116 int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end, 117 gfp_t gfp_mask); 118 void ida_simple_remove(struct ida *ida, unsigned int id); 119 120 static inline void 121 ida_free(struct ida *ida, int id) 122 { 123 124 ida_remove(ida, id); 125 } 126 127 static inline int 128 ida_get_new(struct ida *ida, int *p_id) 129 { 130 131 return (ida_get_new_above(ida, 0, p_id)); 132 } 133 134 static inline int 135 ida_alloc_max(struct ida *ida, unsigned int max, gfp_t gfp) 136 { 137 138 return (ida_simple_get(ida, 0, max, gfp)); 139 } 140 141 static inline int ida_alloc(struct ida *ida, gfp_t gfp) 142 { 143 return (ida_alloc_max(ida, ~0u, gfp)); 144 } 145 146 static inline bool 147 ida_is_empty(struct ida *ida) 148 { 149 150 return (idr_is_empty(&ida->idr)); 151 } 152 153 #endif /* _LINUXKPI_LINUX_IDR_H_ */ 154