diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/xfs/xfs_bit.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/fs/xfs/xfs_bit.c')
-rw-r--r-- | kernel/fs/xfs/xfs_bit.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/kernel/fs/xfs/xfs_bit.c b/kernel/fs/xfs/xfs_bit.c new file mode 100644 index 000000000..0e8885a59 --- /dev/null +++ b/kernel/fs/xfs/xfs_bit.c @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2000-2005 Silicon Graphics, Inc. + * All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include "xfs.h" +#include "xfs_log_format.h" +#include "xfs_bit.h" + +/* + * XFS bit manipulation routines, used in non-realtime code. + */ + +/* + * 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_bitmap_empty(uint *map, uint size) +{ + uint i; + uint ret = 0; + + for (i = 0; i < size; i++) { + ret |= map[i]; + } + + return (ret == 0); +} + +/* + * Count the number of contiguous bits set in the bitmap starting with bit + * start_bit. Size is the size of the bitmap in words. + */ +int +xfs_contig_bits(uint *map, uint size, uint start_bit) +{ + uint * p = ((unsigned int *) map) + (start_bit >> BIT_TO_WORD_SHIFT); + uint result = 0; + uint tmp; + + size <<= BIT_TO_WORD_SHIFT; + + ASSERT(start_bit < size); + size -= start_bit & ~(NBWORD - 1); + start_bit &= (NBWORD - 1); + if (start_bit) { + tmp = *p++; + /* set to one first offset bits prior to start */ + tmp |= (~0U >> (NBWORD-start_bit)); + if (tmp != ~0U) + goto found; + result += NBWORD; + size -= NBWORD; + } + while (size) { + if ((tmp = *p++) != ~0U) + goto found; + result += NBWORD; + size -= NBWORD; + } + return result - start_bit; +found: + return result + ffz(tmp) - start_bit; +} + +/* + * This takes the bit number to start looking from and + * returns the next set bit from there. It returns -1 + * if there are no more bits set or the start bit is + * beyond the end of the bitmap. + * + * Size is the number of words, not bytes, in the bitmap. + */ +int xfs_next_bit(uint *map, uint size, uint start_bit) +{ + uint * p = ((unsigned int *) map) + (start_bit >> BIT_TO_WORD_SHIFT); + uint result = start_bit & ~(NBWORD - 1); + uint tmp; + + size <<= BIT_TO_WORD_SHIFT; + + if (start_bit >= size) + return -1; + size -= result; + start_bit &= (NBWORD - 1); + if (start_bit) { + tmp = *p++; + /* set to zero first offset bits prior to start */ + tmp &= (~0U << start_bit); + if (tmp != 0U) + goto found; + result += NBWORD; + size -= NBWORD; + } + while (size) { + if ((tmp = *p++) != 0U) + goto found; + result += NBWORD; + size -= NBWORD; + } + return -1; +found: + return result + ffs(tmp) - 1; +} |