linux-kernel - [PATCH 4.9 04/29] tools: add more bitmap functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20180604065802.333101611@linuxfoundation.org>
Date:   Mon,  4 Jun 2018 08:58:00 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Matthew Wilcox <willy@...ux.intel.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Konstantin Khlebnikov <koct9i@...il.com>,
        Ross Zwisler <ross.zwisler@...ux.intel.com>,
        Matthew Wilcox <mawilcox@...rosoft.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>
Subject: [PATCH 4.9 04/29] tools: add more bitmap functions

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Matthew Wilcox <willy@...ux.intel.com>

commit b328daf3b7130098b105c18bdae694ddaad5b6e3 upstream.

I need the following functions for the radix tree:

  bitmap_fill
  bitmap_empty
  bitmap_full

Copy the implementations from include/linux/bitmap.h

Signed-off-by: Matthew Wilcox <willy@...ux.intel.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@...il.com>
Cc: Ross Zwisler <ross.zwisler@...ux.intel.com>
Cc: Matthew Wilcox <mawilcox@...rosoft.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 tools/include/linux/bitmap.h |   26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

--- a/tools/include/linux/bitmap.h
+++ b/tools/include/linux/bitmap.h
@@ -35,6 +35,32 @@ static inline void bitmap_zero(unsigned
 	}
 }
 
+static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
+{
+	unsigned int nlongs = BITS_TO_LONGS(nbits);
+	if (!small_const_nbits(nbits)) {
+		unsigned int len = (nlongs - 1) * sizeof(unsigned long);
+		memset(dst, 0xff,  len);
+	}
+	dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
+}
+
+static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
+{
+	if (small_const_nbits(nbits))
+		return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
+
+	return find_first_bit(src, nbits) == nbits;
+}
+
+static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
+{
+	if (small_const_nbits(nbits))
+		return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
+
+	return find_first_zero_bit(src, nbits) == nbits;
+}
+
 static inline int bitmap_weight(const unsigned long *src, int nbits)
 {
 	if (small_const_nbits(nbits))