From patchwork Thu Feb 22 23:28:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 13568327 X-Patchwork-Delegate: snitzer@redhat.com 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 73FC413791F; Thu, 22 Feb 2024 23:28:24 +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=1708644505; cv=none; b=WW0h02MpNprHKs+Wlb8u54sI5yGLay2i3Fxf+9FC69CNH/b+hvKQGcgWJuyLEuhYPR7oLojlAeehwf2Veb30F84epruFLm6zBAyfht72V4Ec4w+79ekT5LazJygOwAKZr4EUm23ZGCRX9+vqLmVfH5551yp0ws4+oYB67ZudceI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708644505; c=relaxed/simple; bh=Fo3k55E/Ng8nqzlSKH7L4NaRCmEvcgtIvJ5iNPD2yFs=; h=Date:To:From:Subject:Message-Id; b=SkfvpHTb3ztINisAjYrs/CFilqQUd+DtSu6nuH3BkaEp5X+n/7fq8M50nZ3d5xJCkAiVIeqXzo8h12YXv7+ibaDR7N/MwhFNAP4a+BKphdX1Vhdu4IAfGujedn0Hjd/p/Bk+Bn0fJY8pRVrbVETqzW2mDsnQCSJ2jgPWujQBOko= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=pf3RAJLu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="pf3RAJLu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02269C433C7; Thu, 22 Feb 2024 23:28:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1708644504; bh=Fo3k55E/Ng8nqzlSKH7L4NaRCmEvcgtIvJ5iNPD2yFs=; h=Date:To:From:Subject:From; b=pf3RAJLu1dFsxoytVPKJPXKBF5TOjf6XkCHgv0GHctIEx+n4iSmsFiMOQ47YmiA5W h2Ej8qWg2Pj163Y7WhpaBvh1jpXSKxWcue7Kc8c1fksJi0sRG03LjEZFfA+QUm+zvg A8Alal0JRT/T3SFMvIfs49kkRWEvmi8aN6o+TN3w= Date: Thu, 22 Feb 2024 15:28:23 -0800 To: mm-commits@vger.kernel.org,willy@infradead.org,vishal.l.verma@intel.com,snitzer@kernel.org,mpatocka@redhat.com,lkp@intel.com,linux@armlinux.org.uk,hch@lst.de,hca@linux.ibm.com,dm-devel@lists.linux.dev,david@fromorbit.com,dave.jiang@intel.com,dan.j.williams@intel.com,arnd@arndb.de,agk@redhat.com,mathieu.desnoyers@efficios.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] dax-alloc_dax-return-err_ptr-eopnotsupp-for-config_dax=n.patch removed from -mm tree Message-Id: <20240222232824.02269C433C7@smtp.kernel.org> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: dax: alloc_dax() return ERR_PTR(-EOPNOTSUPP) for CONFIG_DAX=n has been removed from the -mm tree. Its filename was dax-alloc_dax-return-err_ptr-eopnotsupp-for-config_dax=n.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Mathieu Desnoyers Subject: dax: alloc_dax() return ERR_PTR(-EOPNOTSUPP) for CONFIG_DAX=n Date: Thu, 15 Feb 2024 09:46:26 -0500 Change the return value from NULL to PTR_ERR(-EOPNOTSUPP) for CONFIG_DAX=n to be consistent with the fact that CONFIG_DAX=y never returns NULL. This is done in preparation for using cpu_dcache_is_aliasing() in a following change which will properly support architectures which detect data cache aliasing at runtime. Link: https://lkml.kernel.org/r/20240215144633.96437-3-mathieu.desnoyers@efficios.com Fixes: 4e4ced93794a ("dax: Move mandatory ->zero_page_range() check in alloc_dax()") Signed-off-by: Mathieu Desnoyers Reviewed-by: Dan Williams Cc: Dan Williams Cc: Vishal Verma Cc: Dave Jiang Cc: Matthew Wilcox Cc: Arnd Bergmann Cc: Russell King Cc: Alasdair Kergon Cc: Christoph Hellwig Cc: Dave Chinner Cc: Heiko Carstens Cc: kernel test robot Cc: Michael Sclafani Cc: Mike Snitzer Cc: Mikulas Patocka Signed-off-by: Andrew Morton --- drivers/dax/super.c | 5 +++++ include/linux/dax.h | 6 +----- 2 files changed, 6 insertions(+), 5 deletions(-) --- a/drivers/dax/super.c~dax-alloc_dax-return-err_ptr-eopnotsupp-for-config_dax=n +++ a/drivers/dax/super.c @@ -319,6 +319,11 @@ EXPORT_SYMBOL_GPL(dax_alive); * that any fault handlers or operations that might have seen * dax_alive(), have completed. Any operations that start after * synchronize_srcu() has run will abort upon seeing !dax_alive(). + * + * Note, because alloc_dax() returns an ERR_PTR() on error, callers + * typically store its result into a local variable in order to check + * the result. Therefore, care must be taken to populate the struct + * device dax_dev field make sure the dax_dev is not leaked. */ void kill_dax(struct dax_device *dax_dev) { --- a/include/linux/dax.h~dax-alloc_dax-return-err_ptr-eopnotsupp-for-config_dax=n +++ a/include/linux/dax.h @@ -88,11 +88,7 @@ static inline void *dax_holder(struct da static inline struct dax_device *alloc_dax(void *private, const struct dax_operations *ops) { - /* - * Callers should check IS_ENABLED(CONFIG_DAX) to know if this - * NULL is an error or expected. - */ - return NULL; + return ERR_PTR(-EOPNOTSUPP); } static inline void put_dax(struct dax_device *dax_dev) {