1 files changed, 103 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bit.c b/fs/xfs/xfs_bit.c
index 48228848f5ae..fab0b6d5a41b 100644
--- a/fs/xfs/xfs_bit.c
+++ b/fs/xfs/xfs_bit.c
@@ -25,6 +25,109 @@
 * 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
+/*
+ * 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);
+}
 /*
 * Return whether bitmap is empty.
 * Size is number of words in the bitmap, which is padded to word boundary

diff --git a/fs/xfs/xfs_bit.c b/fs/xfs/xfs_bit.c index 48228848f5ae..fab0b6d5a41b 100644 --- a/fs/xfs/xfs_bit.c +++ b/fs/xfs/xfs_bit.c
@@ -25,6 +25,109 @@
25	* XFS bit manipulation routines, used in non-realtime code.	25	* XFS bit manipulation routines, used in non-realtime code.
26	*/	26	*/
27		27
		28	#ifndef HAVE_ARCH_HIGHBIT
		29	/*
		30	* Index of high bit number in byte, -1 for none set, 0..7 otherwise.
		31	*/
		32	static const char xfs_highbit[256] = {
		33	-1, 0, 1, 1, 2, 2, 2, 2, /* 00 .. 07 */
		34	3, 3, 3, 3, 3, 3, 3, 3, /* 08 .. 0f */
		35	4, 4, 4, 4, 4, 4, 4, 4, /* 10 .. 17 */
		36	4, 4, 4, 4, 4, 4, 4, 4, /* 18 .. 1f */
		37	5, 5, 5, 5, 5, 5, 5, 5, /* 20 .. 27 */
		38	5, 5, 5, 5, 5, 5, 5, 5, /* 28 .. 2f */
		39	5, 5, 5, 5, 5, 5, 5, 5, /* 30 .. 37 */
		40	5, 5, 5, 5, 5, 5, 5, 5, /* 38 .. 3f */
		41	6, 6, 6, 6, 6, 6, 6, 6, /* 40 .. 47 */
		42	6, 6, 6, 6, 6, 6, 6, 6, /* 48 .. 4f */
		43	6, 6, 6, 6, 6, 6, 6, 6, /* 50 .. 57 */
		44	6, 6, 6, 6, 6, 6, 6, 6, /* 58 .. 5f */
		45	6, 6, 6, 6, 6, 6, 6, 6, /* 60 .. 67 */
		46	6, 6, 6, 6, 6, 6, 6, 6, /* 68 .. 6f */
		47	6, 6, 6, 6, 6, 6, 6, 6, /* 70 .. 77 */
		48	6, 6, 6, 6, 6, 6, 6, 6, /* 78 .. 7f */
		49	7, 7, 7, 7, 7, 7, 7, 7, /* 80 .. 87 */
		50	7, 7, 7, 7, 7, 7, 7, 7, /* 88 .. 8f */
		51	7, 7, 7, 7, 7, 7, 7, 7, /* 90 .. 97 */
		52	7, 7, 7, 7, 7, 7, 7, 7, /* 98 .. 9f */
		53	7, 7, 7, 7, 7, 7, 7, 7, /* a0 .. a7 */
		54	7, 7, 7, 7, 7, 7, 7, 7, /* a8 .. af */
		55	7, 7, 7, 7, 7, 7, 7, 7, /* b0 .. b7 */
		56	7, 7, 7, 7, 7, 7, 7, 7, /* b8 .. bf */
		57	7, 7, 7, 7, 7, 7, 7, 7, /* c0 .. c7 */
		58	7, 7, 7, 7, 7, 7, 7, 7, /* c8 .. cf */
		59	7, 7, 7, 7, 7, 7, 7, 7, /* d0 .. d7 */
		60	7, 7, 7, 7, 7, 7, 7, 7, /* d8 .. df */
		61	7, 7, 7, 7, 7, 7, 7, 7, /* e0 .. e7 */
		62	7, 7, 7, 7, 7, 7, 7, 7, /* e8 .. ef */
		63	7, 7, 7, 7, 7, 7, 7, 7, /* f0 .. f7 */
		64	7, 7, 7, 7, 7, 7, 7, 7, /* f8 .. ff */
		65	};
		66	#endif
		67
		68	/*
		69	* xfs_highbit32: get high bit set out of 32-bit argument, -1 if none set.
		70	*/
		71	inline int
		72	xfs_highbit32(
		73	__uint32_t v)
		74	{
		75	#ifdef HAVE_ARCH_HIGHBIT
		76	return highbit32(v);
		77	#else
		78	int i;
		79
		80	if (v & 0xffff0000)
		81	if (v & 0xff000000)
		82	i = 24;
		83	else
		84	i = 16;
		85	else if (v & 0x0000ffff)
		86	if (v & 0x0000ff00)
		87	i = 8;
		88	else
		89	i = 0;
		90	else
		91	return -1;
		92	return i + xfs_highbit[(v >> i) & 0xff];
		93	#endif
		94	}
		95
		96	/*
		97	* xfs_lowbit64: get low bit set out of 64-bit argument, -1 if none set.
		98	*/
		99	int
		100	xfs_lowbit64(
		101	__uint64_t v)
		102	{
		103	__uint32_t w = (__uint32_t)v;
		104	int n = 0;
		105
		106	if (w) { /* lower bits */
		107	n = ffs(w);
		108	} else { /* upper bits */
		109	w = (__uint32_t)(v >> 32);
		110	if (w && (n = ffs(w)))
		111	n += 32;
		112	}
		113	return n - 1;
		114	}
		115
		116	/*
		117	* xfs_highbit64: get high bit set out of 64-bit argument, -1 if none set.
		118	*/
		119	int
		120	xfs_highbit64(
		121	__uint64_t v)
		122	{
		123	__uint32_t h = (__uint32_t)(v >> 32);
		124
		125	if (h)
		126	return xfs_highbit32(h) + 32;
		127	return xfs_highbit32((__uint32_t)v);
		128	}
		129
		130
28	/*	131	/*
29	* Return whether bitmap is empty.	132	* Return whether bitmap is empty.
30	* Size is number of words in the bitmap, which is padded to word boundary	133	* Size is number of words in the bitmap, which is padded to word boundary