From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:55092 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726002AbfFUNjp (ORCPT ); Fri, 21 Jun 2019 09:39:45 -0400 From: Pankaj Gupta Subject: [PATCH v14 5/7] dax: check synchronous mapping is supported Date: Fri, 21 Jun 2019 19:04:53 +0530 Message-Id: <20190621133455.3303-6-pagupta@redhat.com> In-Reply-To: <20190621133455.3303-1-pagupta@redhat.com> References: <20190621133455.3303-1-pagupta@redhat.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: dm-devel@redhat.com, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-acpi@vger.kernel.org, qemu-devel@nongnu.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org Cc: dan.j.williams@intel.com, zwisler@kernel.org, vishal.l.verma@intel.com, dave.jiang@intel.com, mst@redhat.com, jasowang@redhat.com, willy@infradead.org, rjw@rjwysocki.net, hch@infradead.org, lenb@kernel.org, jack@suse.cz, tytso@mit.edu, adilger.kernel@dilger.ca, darrick.wong@oracle.com, lcapitulino@redhat.com, kwolf@redhat.com, imammedo@redhat.com, jmoyer@redhat.com, nilal@redhat.com, riel@surriel.com, stefanha@redhat.com, aarcange@redhat.com, david@redhat.com, david@fromorbit.com, cohuck@redhat.com, xiaoguangrong.eric@gmail.com, pagupta@redhat.com, pbonzini@redhat.com, yuval.shaia@oracle.com, kilobyte@angband.pl, jstaron@google.com, rdunlap@infradead.org, snitzer@redhat.com This patch introduces 'daxdev_mapping_supported' helper which checks if 'MAP_SYNC' is supported with filesystem mapping. It also checks if corresponding dax_device is synchronous. Virtio pmem device is asynchronous and does not not support VM_SYNC. Suggested-by: Jan Kara Signed-off-by: Pankaj Gupta Reviewed-by: Jan Kara --- include/linux/dax.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/include/linux/dax.h b/include/linux/dax.h index 86fc55c99b58..d1bea3979b5a 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -53,6 +53,18 @@ static inline void set_dax_synchronous(struct dax_device *dax_dev) { __set_dax_synchronous(dax_dev); } +/* + * Check if given mapping is supported by the file / underlying device. + */ +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + if (!(vma->vm_flags & VM_SYNC)) + return true; + if (!IS_DAX(file_inode(vma->vm_file))) + return false; + return dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { @@ -87,6 +99,11 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) static inline void set_dax_synchronous(struct dax_device *dax_dev) { } +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + return !(vma->vm_flags & VM_SYNC); +} #endif struct writeback_control; -- 2.20.1