From nobody Tue Dec 16 07:08:45 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C688125A62F for ; Fri, 17 Jan 2025 01:31:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737077468; cv=none; b=OVrpXDBAbHZzJQGn8E0Hvha862dPMt4pW1Wp3UZKSGwSBempcRV+O1V3vRltNDq5F0UGc9zX/m4NNFwDongF7Xrxoyg7Xpo75pCeyViOPzL/F5WT1Gk+dihnZKEJmIWxuUY7f/ylX+JSD9jdGhtfSMh4zkxu4nZk7Eo+trC7Ay4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737077468; c=relaxed/simple; bh=Gf6phLdwpHMJaDpy+vZUWVIeNkMlWtEQYgiasVzanO4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=YXvfC3UjNzrzL9ZKzj6djPYhTlMoAdVaB3SY6iQXCrzRSeT0HGnQfGx528T+IwDxG/pfQf+kueEq3I5kRDGD/enjTfU2FOJrAhixxmTNmNv7VRIAodK1lcQKhlUaOCWKDOVIWYzrpZO59/btfW6FPykpwiGfMVYWLU/ZG4pbKZY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TVs9VIbj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TVs9VIbj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0AEE0C4CEDF; Fri, 17 Jan 2025 01:31:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737077467; bh=Gf6phLdwpHMJaDpy+vZUWVIeNkMlWtEQYgiasVzanO4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TVs9VIbjk5xpy7aaORGBQQYXuvE+DvECCkKs4rZOuHtgv4IBA6xZy70nkNmI43FW4 r/RrhOJds7U9o5P9/gCQCcMB6QYjlkgoTlkW29bdNvDUxnzseHx6dFGF/jv/Rkhzyy LdfgS8HO2gZgLF8JjxFXalOkAWcqKy9avq4mBYHndUdNdpx4FBoDsjugxdGx8DALFf 7nU5lMD7+4yNbD2ogWdDTzups6cVsp3qxDEdDSFrc4pwFIrizADabFWhDAvPzCBW9r kwoDGvMiUWwxfdKwLxS2YRzTynpgL5ALRTvV4c6wY2uiYB87nR6MTC0n9v128ZQ09P QvM/OxLks/rvg== From: SeongJae Park To: Cc: SeongJae Park , "Liam R. Howlett" , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Shakeel Butt , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH v2 1/4] mm/madvise: split out mmap locking operations for madvise() Date: Thu, 16 Jan 2025 17:30:55 -0800 Message-Id: <20250117013058.1843-2-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250117013058.1843-1-sj@kernel.org> References: <20250117013058.1843-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Split out the madvise behavior-dependent mmap_lock operations from do_madvise(), for easier reuse of the logic in an upcoming change. Signed-off-by: SeongJae Park Reviewed-by: Lorenzo Stoakes Reviewed-by: Shakeel Butt --- mm/madvise.c | 45 ++++++++++++++++++++++++++++++++------------- 1 file changed, 32 insertions(+), 13 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index 49f3a75046f6..ae0964bc4d88 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1565,6 +1565,33 @@ int madvise_set_anon_name(struct mm_struct *mm, unsi= gned long start, madvise_vma_anon_name); } #endif /* CONFIG_ANON_VMA_NAME */ + +static int madvise_lock(struct mm_struct *mm, int behavior) +{ + +#ifdef CONFIG_MEMORY_FAILURE + if (behavior =3D=3D MADV_HWPOISON || behavior =3D=3D MADV_SOFT_OFFLINE) + return 0; +#endif + + if (madvise_need_mmap_write(behavior)) { + if (mmap_write_lock_killable(mm)) + return -EINTR; + } else { + mmap_read_lock(mm); + } + return 0; + +} + +static void madvise_unlock(struct mm_struct *mm, int behavior) +{ + if (madvise_need_mmap_write(behavior)) + mmap_write_unlock(mm); + else + mmap_read_unlock(mm); +} + /* * The madvise(2) system call. * @@ -1641,7 +1668,6 @@ int do_madvise(struct mm_struct *mm, unsigned long st= art, size_t len_in, int beh { unsigned long end; int error; - int write; size_t len; struct blk_plug plug; =20 @@ -1663,19 +1689,15 @@ int do_madvise(struct mm_struct *mm, unsigned long = start, size_t len_in, int beh if (end =3D=3D start) return 0; =20 + error =3D madvise_lock(mm, behavior); + if (error) + return error; + #ifdef CONFIG_MEMORY_FAILURE if (behavior =3D=3D MADV_HWPOISON || behavior =3D=3D MADV_SOFT_OFFLINE) return madvise_inject_error(behavior, start, start + len_in); #endif =20 - write =3D madvise_need_mmap_write(behavior); - if (write) { - if (mmap_write_lock_killable(mm)) - return -EINTR; - } else { - mmap_read_lock(mm); - } - start =3D untagged_addr_remote(mm, start); end =3D start + len; =20 @@ -1692,10 +1714,7 @@ int do_madvise(struct mm_struct *mm, unsigned long s= tart, size_t len_in, int beh } blk_finish_plug(&plug); =20 - if (write) - mmap_write_unlock(mm); - else - mmap_read_unlock(mm); + madvise_unlock(mm, behavior); =20 return error; } --=20 2.39.5