From nobody Mon Feb 9 19:31:03 2026 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 40B001E25F7 for ; Wed, 29 Jan 2025 22:42:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738190543; cv=none; b=goRW6U/8QP9/wQQt+GqplCdzEiFED1zXFRcm8DAZ5810JvSGAyJwrX7n4/knAtt9gUyh+5sbTDVJE6bzDjVqK9arqDZQG4UOSPz8Cnwuc6E3HmyLYJvWR9IHqV+z0VIwD5j1yoCPqvLMtW4TEal/4KtK+od2GifM8j1WFGNbFXw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738190543; c=relaxed/simple; bh=iIVz0iaFnVdC85TvJU7bWEbfgairNIkAhFvDjYIxMbk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Ghq+fQq3/z5KKck7y6GUJ2gYw59GZuVWFSXEJ6FSrUUl3+PFdMEL3Aabg5r7uwEDEssGmEcStTe+pTERR5eFnUQT5UOytw/wXG9wfO0MAgmwETCdHX+rOqntcV+jJQzMvPnFc6/JIrSAIPh+zIBjSfd2t6fb/N8iKPG1t63ud24= 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=YCSzIOXF; arc=none smtp.client-ip=209.85.214.202 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="YCSzIOXF" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-21640607349so3640055ad.0 for ; Wed, 29 Jan 2025 14:42:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1738190541; x=1738795341; 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=dXf4/6vVFsOQWOL4yP6AMC2Up5+2J9mezQuBbeYawcA=; b=YCSzIOXFRoaBiOzY+2vIaH5dWYPiSjSR3lSnv3lA3Ta7S0HWdS/L7YOAIePQWW9vC9 1NDZBJmTUoF/dvWhELPNc7YQvA6koCxHb55SvtR64dGDOFqBRbKjw+1v8qqq9VnhL3QB dGmHaaGdyWNjzuozM2ocawrP+tz2luG4fGwmSBXPYYi4xRTC0I+Y8CmMhHo5/g9/oBKL sG+PpJSWUqqCTu8q5J8RBs70ewDdVoMFxudqYRu4HENNyYOwD2ZabOZfh+8NjKhexALS BvMuYsXMFW6k+e6cmD1kZkImjE4jDGZNtIhH5P2/ZiPIpN0s+yKNqAkFOt0inX2SECYF e+Sg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738190541; x=1738795341; 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=dXf4/6vVFsOQWOL4yP6AMC2Up5+2J9mezQuBbeYawcA=; b=wCUyWNUmAqwVWSSzGTeUl7+KUUOQQWMGpZfiFkQtQ0hJwidrgOuRj2mcsKh1Wbarsx hGaFKI4ITJd+vfa5l5PWuxxcpbMygxiva6B2rhj799tnTlkmk9jQtCMw7fIDy6FSk6dw xVXWAWCTylp3uD8l+HEoUheKZLencs6/leK7jChrqoxyN6g4zjqSai298ao00QZI6eQ5 Bg8P+78XVC4H9ZGGn84HdelXq+BKhap1kWaBT+LBx2x5xftLOX2HOXGB9MRzhN283azw P370uNEuUXsh8Di/ELHX6/Ssa6HcFOYkL9qf1gcvJU//X21VCtkJ0y9EhUuvtK0F2NRk Wp8g== X-Forwarded-Encrypted: i=1; AJvYcCXKhfSCYibW0XoVPLOWaO0MfGT4kMO9xIiezNHVL0XH3Ss0+nAMN45pxnivDDGfIUXfBdDzPIpkFOnIIMo=@vger.kernel.org X-Gm-Message-State: AOJu0Yw1uV7WGZStlcfP5dkEpKIVlud/spBwBxhbk51q3q6b4xa+agLP UVU2TgzynS7o/YYNVD4NaCeAjabUH4XHDyWqWEO8yYAOPSiZN6UnPEvJqipGYoGTEvba0g== X-Google-Smtp-Source: AGHT+IFtjyy0fiL5jPCk8tJl4v0XKuHY7KQNCKtXfPi9xeiKgYj5YSOrbzBr7gtJ/uGT4M5R65Qgn0uu X-Received: from pfwy16.prod.google.com ([2002:a05:6a00:1c90:b0:725:e46a:4fdd]) (user=fvdl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a21:458a:b0:1e4:8fdd:8c77 with SMTP id adf61e73a8af0-1ed7a479222mr8328798637.8.1738190541605; Wed, 29 Jan 2025 14:42:21 -0800 (PST) Date: Wed, 29 Jan 2025 22:41:32 +0000 In-Reply-To: <20250129224157.2046079-1-fvdl@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250129224157.2046079-1-fvdl@google.com> X-Mailer: git-send-email 2.48.1.262.g85cc9f2d1e-goog Message-ID: <20250129224157.2046079-4-fvdl@google.com> Subject: [PATCH v2 03/28] 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 Signed-off-by: Frank van der Linden Acked-by: Alexander Gordeev --- 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 c20255161642..1704d5be6a07 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -988,3 +988,24 @@ 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 2.48.1.262.g85cc9f2d1e-goog