/* bit search implementation * * Copied from lib/find_bit.c to tools/lib/find_bit.c * * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * Copyright (C) 2008 IBM Corporation * 'find_last_bit' is written by Rusty Russell * (Inspired by David Howell's find_next_bit implementation) * * Rewritten by Yury Norov to decrease * size and improve performance, 2015. * * 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; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #if !defined(find_next_bit) /* * This is a common helper function for find_next_bit and * find_next_zero_bit. The difference is the "invert" argument, which * is XORed with each fetched word before searching it for one bits. */ static unsigned long _find_next_bit(const unsigned long *addr, unsigned long nbits, unsigned long start, unsigned long invert) { unsigned long tmp; if (!nbits || start >= nbits) return nbits; tmp = addr[start / BITS_PER_LONG] ^ invert; /* Handle 1st word. */ tmp &= BITMAP_FIRST_WORD_MASK(start); start = round_down(start, BITS_PER_LONG); while (!tmp) { start += BITS_PER_LONG; if (start >= nbits) return nbits; tmp = addr[start / BITS_PER_LONG] ^ invert; } return min(start + __ffs(tmp), nbits); } #endif #ifndef find_next_bit /* * Find the next set bit in a memory region. */ unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { return _find_next_bit(addr, size, offset, 0UL); } #endif #ifndef find_first_bit /* * Find the first set bit in a memory region. */ unsigned long find_first_bit(const unsigned long *addr, unsigned long size) { unsigned long idx; for (idx = 0; idx * BITS_PER_LONG < size; idx++) { if (addr[idx]) return min(idx * BITS_PER_LONG + __ffs(addr[idx]), size); } return size; } #endif #ifndef find_first_zero_bit /* * Find the first cleared bit in a memory region. */ unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size) { unsigned long idx; for (idx = 0; idx * BITS_PER_LONG < size; idx++) { if (addr[idx] != ~0UL) return min(idx * BITS_PER_LONG + ffz(addr[idx]), size); } return size; } #endif #ifndef find_next_zero_bit unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { return _find_next_bit(addr, size, offset, ~0UL); } #endif 64c888c0cd0bd66c'>root/fs/xfs/xfs_fsops.h
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authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-24 16:54:39 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-24 16:54:39 -0800
commit883af14e67e8b8702b5560aa64c888c0cd0bd66c (patch)
tree74e3a6b53f5fad9f7848ab1b9f6921b7012940a4 /fs/xfs/xfs_fsops.h
parent0263d4ebd94b36280608e296cba39b924b6e832b (diff)
parentaab45453ff5c77200c6da4ac909f7a4392aed17e (diff)
Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton: "26 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (26 commits) MAINTAINERS: add Dan Streetman to zbud maintainers MAINTAINERS: add Dan Streetman to zswap maintainers mm: do not export ioremap_page_range symbol for external module mn10300: fix build error of missing fpu_save() romfs: use different way to generate fsid for BLOCK or MTD frv: add missing atomic64 operations mm, page_alloc: fix premature OOM when racing with cpuset mems update mm, page_alloc: move cpuset seqcount checking to slowpath mm, page_alloc: fix fast-path race with cpuset update or removal mm, page_alloc: fix check for NULL preferred_zone kernel/panic.c: add missing \n fbdev: color map copying bounds checking frv: add atomic64_add_unless() mm/mempolicy.c: do not put mempolicy before using its nodemask radix-tree: fix private list warnings Documentation/filesystems/proc.txt: add VmPin mm, memcg: do not retry precharge charges proc: add a schedule point in proc_pid_readdir() mm: alloc_contig: re-allow CMA to compact FS pages mm/slub.c: trace free objects at KERN_INFO ...
Diffstat (limited to 'fs/xfs/xfs_fsops.h')