From nobody Fri Dec 19 09:11:00 2025 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 30A6727128E for ; Tue, 18 Feb 2025 18:17:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739902633; cv=none; b=Q4RHBwjFR0jE0oTCJpyLB5Rl6YBnOQ4ofLZsSg4fEaBzq5e7tIzgzPos22UC+Z9+fCMwF21ImQhy/P0OM8gjToXahzsv8/ZmwqwdivBrGm3LycUn9Z3j55dDCx1mhlzW0By7/QtZ6vq20pXCZH59dxulMhnTFRx3wegf8nbSsKA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739902633; c=relaxed/simple; bh=O7o+HWviERTdl/2M2SHuibwM8esj60P3sjEF4srvJ3Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=qAyyjX3ZsVctJfC5H+UmVpd0vwzSvvNQ7IfJQuIvivEeyroku+dblkIezyax6PEM7fBBTd6wUOW+5phlqtwq0PfX6QWUWC+e99mOrxHMfMngmjR45YA04R7zF3X7WDgjMERBF7xw6Yyd9vB8yR/J2LeNI16ELwm/R4D4KHzqeMs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--fvdl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=hhtf70F/; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--fvdl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hhtf70F/" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-2fc1a4c150bso11310483a91.2 for ; Tue, 18 Feb 2025 10:17:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1739902631; x=1740507431; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=tllVc7X/acXyb+IoDErelML7G/kmBDOgXbXRXqPobDE=; b=hhtf70F/Tpngy7+D60Xer0WBEDd/D1wA9YTNjUm0jEpDY9mxHIQFtbl0rzVNtgdKI3 nB3sWoBw3RS5y8BmRal5rdvwEN/TXCF6o7MnZEGy6w8medvluPdkFqMAg0mrivw4vfWb 9oechwNyxMroMwqiQW+JUvgbmCqlD4L0EcwxiLKJw2XAPivZkaVpOqYfHCCS+DEPDN4J o8+4frOLmUsG6oABSFKG+fc+zwsG9zydGqGAP04yz3bGVe9qzP10+b5Af5NkoM8mbFHf Fb0yYMHN9RbDHIHT+XzOJ+mt8vBp4XwogEDcrZVwJ8usU4fLbgVwgkNLFCtH0phK6hwN S5wA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739902631; x=1740507431; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=tllVc7X/acXyb+IoDErelML7G/kmBDOgXbXRXqPobDE=; b=EavudakR3VEZMVX/NzQ6mpVRi1VRNMMGr6fCWiSr0KAQoSJeK8OQCFXCzn0h/iLZm3 eInKDCu0qr/PNw0K6IwsQ/iI0bQG0okaUHF+vVGG+fkz8Yc4EnDa+oQekJVXNq4EQtRR /8u/+3iNwMTtMqeO1y05BxSjc40QImsAb3oRu0a3iIJVOTPyXMBFZiUWGak2jTSsRIFt RYx6KmNU+Q10J6NFFwqiOV+mQkRB2upR++qeqbk3pnHb6Fxibq1j7HE6GsEv3M8weZqV Ia43HZ7+78d7nPb+QT/0ihTd5VbyBlZzzgc3ccAfVtEuAxs7TS4YvBDXjXoUWghgkgB8 aVYg== X-Forwarded-Encrypted: i=1; AJvYcCVt0MdNE7AI2sQGzs6Od+5JPUwFCWIpz+4YV8W8+NViMGPRHbNQNpVFlLiLAGXmmctxux9PhF4H13mTl1k=@vger.kernel.org X-Gm-Message-State: AOJu0YxMhelW95ad8iFbElbw6O+Qn9bX1H7dUDfqVW8zeVg0K4k90t7B jrMEdtwB7xSNzMmzgAiP6RaE2BKq661u2APTRklMoqNaNLBMtC/+E70wnAl5aqiT9R2AGg== X-Google-Smtp-Source: AGHT+IEImgj/kN4IDC2d0OdCVCT/P6/c0Qlb8Kol3LFJI2Z9hlrSwi6kxHopJVJc8L3J73IZc+vlmUAx X-Received: from pjbli10.prod.google.com ([2002:a17:90b:48ca:b0:2ea:448a:8cd1]) (user=fvdl job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90a:d0c6:b0:2fc:a3b7:108a with SMTP id 98e67ed59e1d1-2fca3b711a8mr4781829a91.2.1739902631607; Tue, 18 Feb 2025 10:17:11 -0800 (PST) Date: Tue, 18 Feb 2025 18:16:31 +0000 In-Reply-To: <20250218181656.207178-1-fvdl@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250218181656.207178-1-fvdl@google.com> X-Mailer: git-send-email 2.48.1.601.g30ceb7b040-goog Message-ID: <20250218181656.207178-4-fvdl@google.com> Subject: [PATCH v4 03/27] mm/cma: introduce cma_intersects function From: Frank van der Linden To: akpm@linux-foundation.org, muchun.song@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: yuzhao@google.com, usamaarif642@gmail.com, joao.m.martins@oracle.com, roman.gushchin@linux.dev, Frank van der Linden , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , linux-s390@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Now that CMA areas can have multiple physical ranges, code can't assume a CMA struct represents a base_pfn plus a size, as returned from cma_get_base. Most cases are ok though, since they all explicitly refer to CMA areas that were created using existing interfaces (cma_declare_contiguous_nid or cma_init_reserved_mem), which guarantees they have just one physical range. An exception is the s390 code, which walks all CMA ranges to see if they intersect with a range of memory that is about to be hotremoved. So, in the future, it might run in to multi-range areas. To keep this check working, define a cma_intersects function. This just checks if a physaddr range intersects any of the ranges. Use it in the s390 check. Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: linux-s390@vger.kernel.org Acked-by: Alexander Gordeev Signed-off-by: Frank van der Linden --- arch/s390/mm/init.c | 13 +++++-------- include/linux/cma.h | 1 + mm/cma.c | 21 +++++++++++++++++++++ 3 files changed, 27 insertions(+), 8 deletions(-) diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index f2298f7a3f21..d88cb1c13f7d 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -239,16 +239,13 @@ struct s390_cma_mem_data { static int s390_cma_check_range(struct cma *cma, void *data) { struct s390_cma_mem_data *mem_data; - unsigned long start, end; =20 mem_data =3D data; - start =3D cma_get_base(cma); - end =3D start + cma_get_size(cma); - if (end < mem_data->start) - return 0; - if (start >=3D mem_data->end) - return 0; - return -EBUSY; + + if (cma_intersects(cma, mem_data->start, mem_data->end)) + return -EBUSY; + + return 0; } =20 static int s390_cma_mem_notifier(struct notifier_block *nb, diff --git a/include/linux/cma.h b/include/linux/cma.h index 863427c27dc2..03d85c100dcc 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -53,6 +53,7 @@ extern bool cma_pages_valid(struct cma *cma, const struct= page *pages, unsigned extern bool cma_release(struct cma *cma, const struct page *pages, unsigne= d long count); =20 extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void = *data); +extern bool cma_intersects(struct cma *cma, unsigned long start, unsigned = long end); =20 extern void cma_reserve_pages_on_error(struct cma *cma); =20 diff --git a/mm/cma.c b/mm/cma.c index 6ac9173d3a7d..c7116a5819c5 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -978,3 +978,24 @@ int cma_for_each_area(int (*it)(struct cma *cma, void = *data), void *data) =20 return 0; } + +bool cma_intersects(struct cma *cma, unsigned long start, unsigned long en= d) +{ + int r; + struct cma_memrange *cmr; + unsigned long rstart, rend; + + for (r =3D 0; r < cma->nranges; r++) { + cmr =3D &cma->ranges[r]; + + rstart =3D PFN_PHYS(cmr->base_pfn); + rend =3D PFN_PHYS(cmr->base_pfn + cmr->count); + if (end < rstart) + continue; + if (start >=3D rend) + continue; + return true; + } + + return false; +} --=20 2.48.1.601.g30ceb7b040-goog