From patchwork Fri Feb 2 21:00:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathieu Desnoyers X-Patchwork-Id: 13543450 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (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 7411B12C809; Fri, 2 Feb 2024 21:00:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=167.114.26.122 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706907635; cv=none; b=bSw8vK0PRztuUNPtyKjmSVWwimSMqfJJOJUcX9s+81pcUCS6b2ayE3cBWYy6fKliiA8ajgrE2Et6ZwZWdlhmKN6bCqCbQqWji4k10Dyaffvun99OAQhjXzl1w8HUISE7Gzfrh9/gMCITCQNGOdmpmQxqCOCFJi1grnTk4AsesXw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706907635; c=relaxed/simple; bh=MgteUY0CjaNYCNu4ZJjdjfbOYQwaLS6hDEa6C2rXhOI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=BPPRk6+Tm9RfYA94V9YsiKwrxfqjHTpYQYChBm5JtJYekdUcMBvsG3gY3pBgEAoT9xYbPEu+beFLJieuSMPjQwp4z3PuFPpMcs1XApAiGv+/qsyi9e/HMW3WtQCvEqlJ/O8rEauurzmnia85n2JZXC337D3C1Hevl33oVuX8tDk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=pmLoboe0; arc=none smtp.client-ip=167.114.26.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="pmLoboe0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1706907630; bh=MgteUY0CjaNYCNu4ZJjdjfbOYQwaLS6hDEa6C2rXhOI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pmLoboe0biQmKhxDQSLFLxe9fj2PBsN9j380mMLjyT2JWK4NKO5DYgC1oKms1hE2X mfyhAqyK/4sWjvu2qrc9U3QSqaqdyPHsaoH3DXLzgSTf2MpcJhENZ7zYoOFFmnOuBS gq8dm7ShaBHLybdKCaEnCossjL+YsNN4tFqYabm5/ufcyshuoiCyl85YvJNrai7hcD g/MvYLbhc2C8SRDi3vXOv1e/GsbbwcSRytwt5wh6vd4lIvjdXNaK3Rv4NQtXV9mGyQ qRZcVkbjwe9zctNTJvb9TxZ3hp1mRdRztkjvgnCT6YZP+6xeRdYi1Vjd3i0T8hyz6s 5wJOddiVYFkFw== Received: from thinkos.internal.efficios.com (192-222-143-198.qc.cable.ebox.net [192.222.143.198]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4TRSpk0JNRzX4W; Fri, 2 Feb 2024 16:00:30 -0500 (EST) From: Mathieu Desnoyers To: Dan Williams , Arnd Bergmann , Dave Chinner Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Andrew Morton , Linus Torvalds , Vishal Verma , Dave Jiang , Matthew Wilcox , Russell King , linux-arch@vger.kernel.org, linux-cxl@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-xfs@vger.kernel.org, dm-devel@lists.linux.dev, nvdimm@lists.linux.dev, linux-s390@vger.kernel.org Subject: [RFC PATCH v4 08/12] dax: Fix incorrect list of data cache aliasing architectures Date: Fri, 2 Feb 2024 16:00:15 -0500 Message-Id: <20240202210019.88022-9-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240202210019.88022-1-mathieu.desnoyers@efficios.com> References: <20240202210019.88022-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 commit d92576f1167c ("dax: does not work correctly with virtual aliasing caches") prevents DAX from building on architectures with virtually aliased dcache with: depends on !(ARM || MIPS || SPARC) This check is too broad (e.g. recent ARMv7 don't have virtually aliased dcaches), and also misses many other architectures with virtually aliased data cache. This is a regression introduced in the v4.0 Linux kernel where the dax mount option is removed for 32-bit ARMv7 boards which have no data cache aliasing, and therefore should work fine with FS_DAX. This was turned into the following check in alloc_dax() by a preparatory change: if (ops && (IS_ENABLED(CONFIG_ARM) || IS_ENABLED(CONFIG_MIPS) || IS_ENABLED(CONFIG_SPARC))) return NULL; Use cpu_dcache_is_aliasing() instead to figure out whether the environment has aliasing data caches. Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches") Signed-off-by: Mathieu Desnoyers Cc: Andrew Morton Cc: Linus Torvalds Cc: Dan Williams Cc: Vishal Verma Cc: Dave Jiang Cc: Matthew Wilcox Cc: Arnd Bergmann Cc: Russell King Cc: linux-arch@vger.kernel.org Cc: linux-cxl@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-xfs@vger.kernel.org Cc: dm-devel@lists.linux.dev Cc: nvdimm@lists.linux.dev --- drivers/dax/super.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index ce5bffa86bba..a21a7c262382 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -13,6 +13,7 @@ #include #include #include +#include #include "dax-private.h" /** @@ -455,9 +456,7 @@ struct dax_device *alloc_dax(void *private, const struct dax_operations *ops) * except for device-dax (NULL operations pointer), which does * not use aliased mappings from the kernel. */ - if (ops && (IS_ENABLED(CONFIG_ARM) || - IS_ENABLED(CONFIG_MIPS) || - IS_ENABLED(CONFIG_SPARC))) + if (ops && cpu_dcache_is_aliasing()) return ERR_PTR(-EOPNOTSUPP); if (WARN_ON_ONCE(ops && !ops->zero_page_range))