drivers/staging/lustre/include/linux/libcfs/bitmap.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36 #ifndef _LIBCFS_BITMAP_H_
  37 #define _LIBCFS_BITMAP_H_
  38
  39
  40 typedef struct {
  41         int          size;
  42         unsigned long   data[0];
  43 } cfs_bitmap_t;
  44
  45 #define CFS_BITMAP_SIZE(nbits) \
  46      (((nbits/BITS_PER_LONG)+1)*sizeof(long)+sizeof(cfs_bitmap_t))
  47
  48 static inline
  49 cfs_bitmap_t *CFS_ALLOCATE_BITMAP(int size)
  50 {
  51         cfs_bitmap_t *ptr;
  52
  53         OBD_ALLOC(ptr, CFS_BITMAP_SIZE(size));
  54         if (ptr == NULL)
  55                 RETURN(ptr);
  56
  57         ptr->size = size;
  58
  59         RETURN (ptr);
  60 }
  61
  62 #define CFS_FREE_BITMAP(ptr)    OBD_FREE(ptr, CFS_BITMAP_SIZE(ptr->size))
  63
  64 static inline
  65 void cfs_bitmap_set(cfs_bitmap_t *bitmap, int nbit)
  66 {
  67         set_bit(nbit, bitmap->data);
  68 }
  69
  70 static inline
  71 void cfs_bitmap_clear(cfs_bitmap_t *bitmap, int nbit)
  72 {
  73         test_and_clear_bit(nbit, bitmap->data);
  74 }
  75
  76 static inline
  77 int cfs_bitmap_check(cfs_bitmap_t *bitmap, int nbit)
  78 {
  79         return test_bit(nbit, bitmap->data);
  80 }
  81
  82 static inline
  83 int cfs_bitmap_test_and_clear(cfs_bitmap_t *bitmap, int nbit)
  84 {
  85         return test_and_clear_bit(nbit, bitmap->data);
  86 }
  87
  88 /* return 0 is bitmap has none set bits */
  89 static inline
  90 int cfs_bitmap_check_empty(cfs_bitmap_t *bitmap)
  91 {
  92         return find_first_bit(bitmap->data, bitmap->size) == bitmap->size;
  93 }
  94
  95 static inline
  96 void cfs_bitmap_copy(cfs_bitmap_t *new, cfs_bitmap_t *old)
  97 {
  98         int newsize;
  99
 100         LASSERT(new->size >= old->size);
 101         newsize = new->size;
 102         memcpy(new, old, CFS_BITMAP_SIZE(old->size));
 103         new->size = newsize;
 104 }
 105
 106 #define cfs_foreach_bit(bitmap, pos)                                    \
 107         for ((pos) = find_first_bit((bitmap)->data, bitmap->size);      \
 108              (pos) < (bitmap)->size;                                    \
 109              (pos) = find_next_bit((bitmap)->data, (bitmap)->size, (pos) + 1))
 110
 111 #endif