[XFS] Use the generic bitops rather than implementing them ourselves.
This keeps xfs_lowbit64 as it was since there aren't good generic helpers
there ... Patch inspired by Andi Kleen.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31472a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/xfs_bit.c b/fs/xfs/xfs_bit.c
index fab0b6d..4822884 100644
--- a/fs/xfs/xfs_bit.c
+++ b/fs/xfs/xfs_bit.c
@@ -25,109 +25,6 @@
* 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.h b/fs/xfs/xfs_bit.h
index 082641a..8e0e463 100644
--- a/fs/xfs/xfs_bit.h
+++ b/fs/xfs/xfs_bit.h
@@ -47,13 +47,39 @@
}
/* Get high bit set out of 32-bit argument, -1 if none set */
-extern int xfs_highbit32(__uint32_t v);
-
-/* Get low bit set out of 64-bit argument, -1 if none set */
-extern int xfs_lowbit64(__uint64_t v);
+static inline int xfs_highbit32(__uint32_t v)
+{
+ return fls(v) - 1;
+}
/* Get high bit set out of 64-bit argument, -1 if none set */
-extern int xfs_highbit64(__uint64_t);
+static inline int xfs_highbit64(__uint64_t v)
+{
+ return fls64(v) - 1;
+}
+
+/* Get low bit set out of 32-bit argument, -1 if none set */
+static inline int xfs_lowbit32(__uint32_t v)
+{
+ unsigned long t = v;
+ return (v) ? find_first_bit(&t, 32) : -1;
+}
+
+/* Get low bit set out of 64-bit argument, -1 if none set */
+static inline 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;
+}
/* Return whether bitmap is empty (1 == empty) */
extern int xfs_bitmap_empty(uint *map, uint size);
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index bf87a59..e2f68de 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -74,18 +74,6 @@
*/
/*
- * xfs_lowbit32: get low bit set out of 32-bit argument, -1 if none set.
- */
-STATIC int
-xfs_lowbit32(
- __uint32_t v)
-{
- if (v)
- return ffs(v) - 1;
- return -1;
-}
-
-/*
* Allocate space to the bitmap or summary file, and zero it, for growfs.
*/
STATIC int /* error */
@@ -450,6 +438,7 @@
}
bbno = XFS_BITTOBLOCK(mp, bno);
i = 0;
+ ASSERT(minlen != 0);
log2len = xfs_highbit32(minlen);
/*
* Loop over all bitmap blocks (bbno + i is current block).
@@ -618,6 +607,8 @@
xfs_suminfo_t sum; /* summary information for extents */
ASSERT(minlen % prod == 0 && maxlen % prod == 0);
+ ASSERT(maxlen != 0);
+
/*
* Loop over all the levels starting with maxlen.
* At each level, look at all the bitmap blocks, to see if there
@@ -675,6 +666,9 @@
*rtblock = NULLRTBLOCK;
return 0;
}
+ ASSERT(minlen != 0);
+ ASSERT(maxlen != 0);
+
/*
* Loop over sizes, from maxlen down to minlen.
* This time, when we do the allocations, allow smaller ones
@@ -1961,6 +1955,7 @@
nsbp->sb_blocksize * nsbp->sb_rextsize);
nsbp->sb_rextents = nsbp->sb_rblocks;
do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
+ ASSERT(nsbp->sb_rextents != 0);
nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
nrsumsize =