From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH 15/22] lmb: Add lmb_reserve_area_overlap_ok() Date: Mon, 10 May 2010 16:34:41 +1000 Message-ID: <1273473281.23699.50.camel@pasglop> References: <1273331860-14325-1-git-send-email-yinghai@kernel.org> <1273331860-14325-16-git-send-email-yinghai@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from gate.crashing.org ([63.228.1.57]:46459 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755351Ab0EJGi3 (ORCPT ); Mon, 10 May 2010 02:38:29 -0400 In-Reply-To: <1273331860-14325-16-git-send-email-yinghai@kernel.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Yinghai Lu Cc: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Andrew Morton , David Miller , Linus Torvalds , Johannes Weiner , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org On Sat, 2010-05-08 at 08:17 -0700, Yinghai Lu wrote: > Some areas from firmware could be reserved several times from different callers. > > If these area are overlapped, We may have overlapped entries in lmb.reserved. > > Try to free the area at first, before rerserve them again. I explained earlier that name sucked :-) We just need to make lmb_reserve() capable of dealing with overlaps instead. I like the idea of implementing that with a free. Cheers, Ben. > Signed-off-by: Yinghai Lu > --- > include/linux/lmb.h | 1 + > mm/lmb.c | 27 +++++++++++++++++++++++++-- > 2 files changed, 26 insertions(+), 2 deletions(-) > > diff --git a/include/linux/lmb.h b/include/linux/lmb.h > index 90022c1..47b9d7f 100644 > --- a/include/linux/lmb.h > +++ b/include/linux/lmb.h > @@ -87,6 +87,7 @@ lmb_end_pfn(struct lmb_region *type, unsigned long region_nr) > } > > void lmb_reserve_area(u64 start, u64 end, char *name); > +void lmb_reserve_area_overlap_ok(u64 start, u64 end, char *name); > void lmb_free_area(u64 start, u64 end); > void lmb_add_memory(u64 start, u64 end); > u64 __lmb_find_area(u64 ei_start, u64 ei_last, u64 start, u64 end, > diff --git a/mm/lmb.c b/mm/lmb.c > index 2870dd9..decea60 100644 > --- a/mm/lmb.c > +++ b/mm/lmb.c > @@ -605,6 +605,12 @@ void __init lmb_add_memory(u64 start, u64 end) > __check_and_double_region_array(&lmb.memory, &lmb_memory_region[0]); > } > > +static void __init __lmb_reserve_area(u64 start, u64 end, char *name) > +{ > + lmb_add_region(&lmb.reserved, start, end - start); > + __check_and_double_region_array(&lmb.reserved, &lmb_reserved_region[0]); > +} > + > void __init lmb_reserve_area(u64 start, u64 end, char *name) > { > if (start == end) > @@ -613,8 +619,25 @@ void __init lmb_reserve_area(u64 start, u64 end, char *name) > if (WARN_ONCE(start > end, "lmb_reserve_area: wrong range [%#llx, %#llx]\n", start, end)) > return; > > - lmb_add_region(&lmb.reserved, start, end - start); > - __check_and_double_region_array(&lmb.reserved, &lmb_reserved_region[0]); > + __lmb_reserve_area(start, end, name); > +} > + > +/* > + * Could be used to avoid having overlap entries in lmb.reserved.region. > + * Don't need to use it with area that is from lmb_find_area() > + * Only use it for the area that fw hidden area. > + */ > +void __init lmb_reserve_area_overlap_ok(u64 start, u64 end, char *name) > +{ > + if (start == end) > + return; > + > + if (WARN_ONCE(start > end, "lmb_reserve_area_overlap_ok: wrong range [%#llx, %#llx]\n", start, end)) > + return; > + > + /* Free that region at first */ > + lmb_free(start, end - start); > + __lmb_reserve_area(start, end, name); > } > > void __init lmb_free_area(u64 start, u64 end)