net/mlx4/alloc.c

37 #include <linux/bitmap.h>
43 u32 mlx4_bitmap_alloc(struct mlx4_bitmap *bitmap)
47 	spin_lock(&bitmap->lock);
49 	obj = find_next_zero_bit(bitmap->table, bitmap->max, bitmap->last);
50 	if (obj >= bitmap->max) {
51 		bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
52 				& bitmap->mask;
53 		obj = find_first_zero_bit(bitmap->table, bitmap->max);
56 	if (obj < bitmap->max) {
57 		set_bit(obj, bitmap->table);
58 		bitmap->last = (obj + 1);
59 		if (bitmap->last == bitmap->max)
60 			bitmap->last = 0;
61 		obj |= bitmap->top;
66 		--bitmap->avail;
68 	spin_unlock(&bitmap->lock);
73 void mlx4_bitmap_free(struct mlx4_bitmap *bitmap, u32 obj)
75 	mlx4_bitmap_free_range(bitmap, obj, 1);
78 static unsigned long find_aligned_range(unsigned long *bitmap,
87 	while ((start < nbits) && test_bit(start, bitmap))
98 		if (test_bit(i, bitmap)) {
107 u32 mlx4_bitmap_alloc_range(struct mlx4_bitmap *bitmap, int cnt, int align)
112 		return mlx4_bitmap_alloc(bitmap);
114 	spin_lock(&bitmap->lock);
116 	obj = find_aligned_range(bitmap->table, bitmap->last,
117 				 bitmap->max, cnt, align);
118 	if (obj >= bitmap->max) {
119 		bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
120 				& bitmap->mask;
121 		obj = find_aligned_range(bitmap->table, 0, bitmap->max,
125 	if (obj < bitmap->max) {
127 			set_bit(obj + i, bitmap->table);
128 		if (obj == bitmap->last) {
129 			bitmap->last = (obj + cnt);
130 			if (bitmap->last >= bitmap->max)
131 				bitmap->last = 0;
133 		obj |= bitmap->top;
138 		bitmap->avail -= cnt;
140 	spin_unlock(&bitmap->lock);
145 u32 mlx4_bitmap_avail(struct mlx4_bitmap *bitmap)
147 	return bitmap->avail;
150 void mlx4_bitmap_free_range(struct mlx4_bitmap *bitmap, u32 obj, int cnt)
154 	obj &= bitmap->max + bitmap->reserved_top - 1;
156 	spin_lock(&bitmap->lock);
158 		clear_bit(obj + i, bitmap->table);
159 	bitmap->last = min(bitmap->last, obj);
160 	bitmap->top = (bitmap->top + bitmap->max + bitmap->reserved_top)
161 			& bitmap->mask;
162 	bitmap->avail += cnt;
163 	spin_unlock(&bitmap->lock);
166 int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask,
175 	bitmap->last = 0;
176 	bitmap->top  = 0;
177 	bitmap->max  = num - reserved_top;
178 	bitmap->mask = mask;
179 	bitmap->reserved_top = reserved_top;
180 	bitmap->avail = num - reserved_top - reserved_bot;
181 	spin_lock_init(&bitmap->lock);
182 	bitmap->table = kzalloc(BITS_TO_LONGS(bitmap->max) *
184 	if (!bitmap->table)
188 		set_bit(i, bitmap->table);
193 void mlx4_bitmap_cleanup(struct mlx4_bitmap *bitmap)
195 	kfree(bitmap->table);