From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Dr. David Alan Gilbert" Subject: Re: [QEMU v2 7/9] bitmap: Add a new bitmap_move function Date: Mon, 1 Aug 2016 12:25:37 +0100 Message-ID: <20160801112536.GB3858@work-vm> References: <1468550849-22172-1-git-send-email-liang.z.li@intel.com> <1468550849-22172-8-git-send-email-liang.z.li@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: qemu-devel@nongnu.org, mst@redhat.com, pbonzini@redhat.com, quintela@redhat.com, amit.shah@redhat.com, kvm@vger.kernel.org, thuth@redhat.com To: Liang Li Return-path: Received: from mx1.redhat.com ([209.132.183.28]:52172 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753105AbcHALZm (ORCPT ); Mon, 1 Aug 2016 07:25:42 -0400 Content-Disposition: inline In-Reply-To: <1468550849-22172-8-git-send-email-liang.z.li@intel.com> Sender: kvm-owner@vger.kernel.org List-ID: * Liang Li (liang.z.li@intel.com) wrote: > Sometimes, it is need to move a portion of bitmap to another place > in a large bitmap, if overlap happens, the bitmap_copy can't not > work correctly, we need a new function to do this work. > > Signed-off-by: Liang Li Reviewed-by: Dr. David Alan Gilbert > --- > include/qemu/bitmap.h | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/include/qemu/bitmap.h b/include/qemu/bitmap.h > index ec5146f..6ac89ca 100644 > --- a/include/qemu/bitmap.h > +++ b/include/qemu/bitmap.h > @@ -37,6 +37,7 @@ > * bitmap_set(dst, pos, nbits) Set specified bit area > * bitmap_set_atomic(dst, pos, nbits) Set specified bit area with atomic ops > * bitmap_clear(dst, pos, nbits) Clear specified bit area > + * bitmap_move(dst, src, nbits) Move *src to *dst > * bitmap_test_and_clear_atomic(dst, pos, nbits) Test and clear area > * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area > */ > @@ -136,6 +137,18 @@ static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, > } > } > > +static inline void bitmap_move(unsigned long *dst, const unsigned long *src, > + long nbits) > +{ > + if (small_nbits(nbits)) { > + unsigned long tmp = *src; > + *dst = tmp; > + } else { > + long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); > + memmove(dst, src, len); > + } > +} > + > static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, > const unsigned long *src2, long nbits) > { > -- > 1.9.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK