diff options
| -rw-r--r-- | include/linux/bitmap.h | 64 | ||||
| -rw-r--r-- | lib/bitmap.c | 64 |
2 files changed, 61 insertions, 67 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 1cca950a54ae..99451431e4d6 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -6,6 +6,7 @@ #include <linux/align.h> #include <linux/bitops.h> +#include <linux/errno.h> #include <linux/find.h> #include <linux/limits.h> #include <linux/string.h> @@ -209,9 +210,6 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig, const unsigned long *relmap, unsigned int bits); void bitmap_fold(unsigned long *dst, const unsigned long *orig, unsigned int sz, unsigned int nbits); -int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); -void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); -int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) @@ -498,6 +496,66 @@ static inline void bitmap_next_set_region(unsigned long *bitmap, } /** + * bitmap_release_region - release allocated bitmap region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @pos: beginning of bit region to release + * @order: region size (log base 2 of number of bits) to release + * + * This is the complement to __bitmap_find_free_region() and releases + * the found region (by clearing it in the bitmap). + */ +static inline void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) +{ + bitmap_clear(bitmap, pos, BIT(order)); +} + +/** + * bitmap_allocate_region - allocate bitmap region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @pos: beginning of bit region to allocate + * @order: region size (log base 2 of number of bits) to allocate + * + * Allocate (set bits in) a specified region of a bitmap. + * + * Returns: 0 on success, or %-EBUSY if specified region wasn't + * free (not all bits were zero). + */ +static inline int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) +{ + unsigned int len = BIT(order); + + if (find_next_bit(bitmap, pos + len, pos) < pos + len) + return -EBUSY; + bitmap_set(bitmap, pos, len); + return 0; +} + +/** + * bitmap_find_free_region - find a contiguous aligned mem region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @bits: number of bits in the bitmap + * @order: region size (log base 2 of number of bits) to find + * + * Find a region of free (zero) bits in a @bitmap of @bits bits and + * allocate them (set them to one). Only consider regions of length + * a power (@order) of two, aligned to that power of two, which + * makes the search algorithm much faster. + * + * Returns: the bit offset in bitmap of the allocated region, + * or -errno on failure. + */ +static inline int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) +{ + unsigned int pos, end; /* scans bitmap by regions of size order */ + + for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) { + if (!bitmap_allocate_region(bitmap, pos, order)) + return pos; + } + return -ENOMEM; +} + +/** * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap. * @n: u64 value * diff --git a/lib/bitmap.c b/lib/bitmap.c index 66da8c33fb1b..09522af227f1 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -8,7 +8,6 @@ #include <linux/bitops.h> #include <linux/ctype.h> #include <linux/device.h> -#include <linux/errno.h> #include <linux/export.h> #include <linux/slab.h> @@ -708,69 +707,6 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig, } #endif /* CONFIG_NUMA */ -/** - * bitmap_find_free_region - find a contiguous aligned mem region - * @bitmap: array of unsigned longs corresponding to the bitmap - * @bits: number of bits in the bitmap - * @order: region size (log base 2 of number of bits) to find - * - * Find a region of free (zero) bits in a @bitmap of @bits bits and - * allocate them (set them to one). Only consider regions of length - * a power (@order) of two, aligned to that power of two, which - * makes the search algorithm much faster. - * - * Return: the bit offset in bitmap of the allocated region, - * or -errno on failure. - */ -int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) -{ - unsigned int pos, end; /* scans bitmap by regions of size order */ - - for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) { - if (!bitmap_allocate_region(bitmap, pos, order)) - return pos; - } - return -ENOMEM; -} -EXPORT_SYMBOL(bitmap_find_free_region); - -/** - * bitmap_release_region - release allocated bitmap region - * @bitmap: array of unsigned longs corresponding to the bitmap - * @pos: beginning of bit region to release - * @order: region size (log base 2 of number of bits) to release - * - * This is the complement to __bitmap_find_free_region() and releases - * the found region (by clearing it in the bitmap). - */ -void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) -{ - bitmap_clear(bitmap, pos, BIT(order)); -} -EXPORT_SYMBOL(bitmap_release_region); - -/** - * bitmap_allocate_region - allocate bitmap region - * @bitmap: array of unsigned longs corresponding to the bitmap - * @pos: beginning of bit region to allocate - * @order: region size (log base 2 of number of bits) to allocate - * - * Allocate (set bits in) a specified region of a bitmap. - * - * Return: 0 on success, or %-EBUSY if specified region wasn't - * free (not all bits were zero). - */ -int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) -{ - unsigned int len = BIT(order); - - if (find_next_bit(bitmap, pos + len, pos) < pos + len) - return -EBUSY; - bitmap_set(bitmap, pos, len); - return 0; -} -EXPORT_SYMBOL(bitmap_allocate_region); - unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) { return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), |