X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=fs%2Fxfs%2Fxfs_bit.c;h=48228848f5ae3e2e6f52900b6d0ea7215274a36d;hb=989b0b930218661b504bbb056b309e2c7bcdfb86;hp=43be6a7e47c6ed1a1b582cb8d91416ae84fa8c25;hpb=8cedcfd43a0b00741fff43d6a4c1a8b7748db3b0;p=linux-2.6-omap-h63xx.git diff --git a/fs/xfs/xfs_bit.c b/fs/xfs/xfs_bit.c index 43be6a7e47c..48228848f5a 100644 --- a/fs/xfs/xfs_bit.c +++ b/fs/xfs/xfs_bit.c @@ -25,198 +25,22 @@ * XFS bit manipulation routines, used in non-realtime code. */ -#ifndef HAVE_ARCH_HIGHBIT /* - * Index of high bit number in byte, -1 for none set, 0..7 otherwise. - */ -STATIC const char xfs_highbit[256] = { - -1, 0, 1, 1, 2, 2, 2, 2, /* 00 .. 07 */ - 3, 3, 3, 3, 3, 3, 3, 3, /* 08 .. 0f */ - 4, 4, 4, 4, 4, 4, 4, 4, /* 10 .. 17 */ - 4, 4, 4, 4, 4, 4, 4, 4, /* 18 .. 1f */ - 5, 5, 5, 5, 5, 5, 5, 5, /* 20 .. 27 */ - 5, 5, 5, 5, 5, 5, 5, 5, /* 28 .. 2f */ - 5, 5, 5, 5, 5, 5, 5, 5, /* 30 .. 37 */ - 5, 5, 5, 5, 5, 5, 5, 5, /* 38 .. 3f */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 40 .. 47 */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 48 .. 4f */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 50 .. 57 */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 58 .. 5f */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 60 .. 67 */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 68 .. 6f */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 70 .. 77 */ - 6, 6, 6, 6, 6, 6, 6, 6, /* 78 .. 7f */ - 7, 7, 7, 7, 7, 7, 7, 7, /* 80 .. 87 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* 88 .. 8f */ - 7, 7, 7, 7, 7, 7, 7, 7, /* 90 .. 97 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* 98 .. 9f */ - 7, 7, 7, 7, 7, 7, 7, 7, /* a0 .. a7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* a8 .. af */ - 7, 7, 7, 7, 7, 7, 7, 7, /* b0 .. b7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* b8 .. bf */ - 7, 7, 7, 7, 7, 7, 7, 7, /* c0 .. c7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* c8 .. cf */ - 7, 7, 7, 7, 7, 7, 7, 7, /* d0 .. d7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* d8 .. df */ - 7, 7, 7, 7, 7, 7, 7, 7, /* e0 .. e7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* e8 .. ef */ - 7, 7, 7, 7, 7, 7, 7, 7, /* f0 .. f7 */ - 7, 7, 7, 7, 7, 7, 7, 7, /* f8 .. ff */ -}; -#endif - -/* - * Count of bits set in byte, 0..8. - */ -static const char xfs_countbit[256] = { - 0, 1, 1, 2, 1, 2, 2, 3, /* 00 .. 07 */ - 1, 2, 2, 3, 2, 3, 3, 4, /* 08 .. 0f */ - 1, 2, 2, 3, 2, 3, 3, 4, /* 10 .. 17 */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 18 .. 1f */ - 1, 2, 2, 3, 2, 3, 3, 4, /* 20 .. 27 */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 28 .. 2f */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 30 .. 37 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* 38 .. 3f */ - 1, 2, 2, 3, 2, 3, 3, 4, /* 40 .. 47 */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 48 .. 4f */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 50 .. 57 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* 58 .. 5f */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 60 .. 67 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* 68 .. 6f */ - 3, 4, 4, 5, 4, 5, 5, 6, /* 70 .. 77 */ - 4, 5, 5, 6, 5, 6, 6, 7, /* 78 .. 7f */ - 1, 2, 2, 3, 2, 3, 3, 4, /* 80 .. 87 */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 88 .. 8f */ - 2, 3, 3, 4, 3, 4, 4, 5, /* 90 .. 97 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* 98 .. 9f */ - 2, 3, 3, 4, 3, 4, 4, 5, /* a0 .. a7 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* a8 .. af */ - 3, 4, 4, 5, 4, 5, 5, 6, /* b0 .. b7 */ - 4, 5, 5, 6, 5, 6, 6, 7, /* b8 .. bf */ - 2, 3, 3, 4, 3, 4, 4, 5, /* c0 .. c7 */ - 3, 4, 4, 5, 4, 5, 5, 6, /* c8 .. cf */ - 3, 4, 4, 5, 4, 5, 5, 6, /* d0 .. d7 */ - 4, 5, 5, 6, 5, 6, 6, 7, /* d8 .. df */ - 3, 4, 4, 5, 4, 5, 5, 6, /* e0 .. e7 */ - 4, 5, 5, 6, 5, 6, 6, 7, /* e8 .. ef */ - 4, 5, 5, 6, 5, 6, 6, 7, /* f0 .. f7 */ - 5, 6, 6, 7, 6, 7, 7, 8, /* f8 .. ff */ -}; - -/* - * xfs_highbit32: get high bit set out of 32-bit argument, -1 if none set. - */ -inline int -xfs_highbit32( - __uint32_t v) -{ -#ifdef HAVE_ARCH_HIGHBIT - return highbit32(v); -#else - int i; - - if (v & 0xffff0000) - if (v & 0xff000000) - i = 24; - else - i = 16; - else if (v & 0x0000ffff) - if (v & 0x0000ff00) - i = 8; - else - i = 0; - else - return -1; - return i + xfs_highbit[(v >> i) & 0xff]; -#endif -} - -/* - * xfs_lowbit64: get low bit set out of 64-bit argument, -1 if none set. - */ -int -xfs_lowbit64( - __uint64_t v) -{ - __uint32_t w = (__uint32_t)v; - int n = 0; - - if (w) { /* lower bits */ - n = ffs(w); - } else { /* upper bits */ - w = (__uint32_t)(v >> 32); - if (w && (n = ffs(w))) - n += 32; - } - return n - 1; -} - -/* - * xfs_highbit64: get high bit set out of 64-bit argument, -1 if none set. - */ -int -xfs_highbit64( - __uint64_t v) -{ - __uint32_t h = (__uint32_t)(v >> 32); - - if (h) - return xfs_highbit32(h) + 32; - return xfs_highbit32((__uint32_t)v); -} - - -/* - * Count the number of bits set in the bitmap starting with bit - * start_bit. Size is the size of the bitmap in words. - * - * Do the counting by mapping a byte value to the number of set - * bits for that value using the xfs_countbit array, i.e. - * xfs_countbit[0] == 0, xfs_countbit[1] == 1, xfs_countbit[2] == 1, - * xfs_countbit[3] == 2, etc. + * Return whether bitmap is empty. + * Size is number of words in the bitmap, which is padded to word boundary + * Returns 1 for empty, 0 for non-empty. */ int -xfs_count_bits(uint *map, uint size, uint start_bit) +xfs_bitmap_empty(uint *map, uint size) { - register int bits; - register unsigned char *bytep; - register unsigned char *end_map; - int byte_bit; - - bits = 0; - end_map = (char*)(map + size); - bytep = (char*)(map + (start_bit & ~0x7)); - byte_bit = start_bit & 0x7; - - /* - * If the caller fell off the end of the map, return 0. - */ - if (bytep >= end_map) { - return (0); - } - - /* - * If start_bit is not byte aligned, then process the - * first byte separately. - */ - if (byte_bit != 0) { - /* - * Shift off the bits we don't want to look at, - * before indexing into xfs_countbit. - */ - bits += xfs_countbit[(*bytep >> byte_bit)]; - bytep++; - } + uint i; + uint ret = 0; - /* - * Count the bits in each byte until the end of the bitmap. - */ - while (bytep < end_map) { - bits += xfs_countbit[*bytep]; - bytep++; + for (i = 0; i < size; i++) { + ret |= map[i]; } - return (bits); + return (ret == 0); } /*