#include <linux/bitops.h>
#include <linux/ctype.h>
#include <linux/device.h>
-#include <linux/errno.h>
#include <linux/export.h>
#include <linux/slab.h>
}
#endif /* CONFIG_NUMA */
-/*
- * Common code for bitmap_*_region() routines.
- * bitmap: array of unsigned longs corresponding to the bitmap
- * pos: the beginning of the region
- * order: region size (log base 2 of number of bits)
- * reg_op: operation(s) to perform on that region of bitmap
- *
- * Can set, verify and/or release a region of bits in a bitmap,
- * depending on which combination of REG_OP_* flag bits is set.
- *
- * A region of a bitmap is a sequence of bits in the bitmap, of
- * some size '1 << order' (a power of two), aligned to that same
- * '1 << order' power of two.
- *
- * Return: 1 if REG_OP_ISFREE succeeds (region is all zero bits).
- * 0 in all other cases and reg_ops.
- */
-
-enum {
- REG_OP_ISFREE, /* true if region is all zero bits */
- REG_OP_ALLOC, /* set all bits in region */
- REG_OP_RELEASE, /* clear all bits in region */
-};
-
-static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op)
-{
- int nbits_reg; /* number of bits in region */
- int index; /* index first long of region in bitmap */
- int offset; /* bit offset region in bitmap[index] */
- int nlongs_reg; /* num longs spanned by region in bitmap */
- int nbitsinlong; /* num bits of region in each spanned long */
- unsigned long mask; /* bitmask for one long of region */
- int i; /* scans bitmap by longs */
- int ret = 0; /* return value */
-
- /*
- * Either nlongs_reg == 1 (for small orders that fit in one long)
- * or (offset == 0 && mask == ~0UL) (for larger multiword orders.)
- */
- nbits_reg = 1 << order;
- index = pos / BITS_PER_LONG;
- offset = pos - (index * BITS_PER_LONG);
- nlongs_reg = BITS_TO_LONGS(nbits_reg);
- nbitsinlong = min(nbits_reg, BITS_PER_LONG);
-
- /*
- * Can't do "mask = (1UL << nbitsinlong) - 1", as that
- * overflows if nbitsinlong == BITS_PER_LONG.
- */
- mask = (1UL << (nbitsinlong - 1));
- mask += mask - 1;
- mask <<= offset;
-
- switch (reg_op) {
- case REG_OP_ISFREE:
- for (i = 0; i < nlongs_reg; i++) {
- if (bitmap[index + i] & mask)
- goto done;
- }
- ret = 1; /* all bits in region free (zero) */
- break;
-
- case REG_OP_ALLOC:
- for (i = 0; i < nlongs_reg; i++)
- bitmap[index + i] |= mask;
- break;
-
- case REG_OP_RELEASE:
- for (i = 0; i < nlongs_reg; i++)
- bitmap[index + i] &= ~mask;
- break;
- }
-done:
- return ret;
-}
-
-/**
- * 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 (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
- 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),
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