From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pankaj Gupta Subject: [PATCH v10 5/7] dax: check synchronous mapping is supported Date: Tue, 21 May 2019 19:07:11 +0530 Message-ID: <20190521133713.31653-6-pagupta__26497.168447689$1558446189$gmane$org@redhat.com> References: <20190521133713.31653-1-pagupta@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190521133713.31653-1-pagupta@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: 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, dm-devel@redhat.com Cc: pagupta@redhat.com, rdunlap@infradead.org, jack@suse.cz, snitzer@redhat.com, mst@redhat.com, david@fromorbit.com, lcapitulino@redhat.com, adilger.kernel@dilger.ca, zwisler@kernel.org, aarcange@redhat.com, dave.jiang@intel.com, jstaron@google.com, darrick.wong@oracle.com, vishal.l.verma@intel.com, willy@infradead.org, hch@infradead.org, jmoyer@redhat.com, nilal@redhat.com, lenb@kernel.org, kilobyte@angband.pl, riel@surriel.com, yuval.shaia@oracle.com, stefanha@redhat.com, pbonzini@redhat.com, dan.j.williams@intel.com, tytso@mit.edu, xiaoguangrong.eric@gmail.com, cohuck@redhat.com, rjw@rjwysocki.net, imammedo@redhat.com List-Id: virtualization@lists.linuxfoundation.org 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 2b106752b1b8..267251a394fa 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -42,6 +42,18 @@ void dax_write_cache(struct dax_device *dax_dev, bool wc); bool dax_write_cache_enabled(struct dax_device *dax_dev); bool dax_synchronous(struct dax_device *dax_dev); void set_dax_synchronous(struct dax_device *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) { @@ -69,6 +81,11 @@ static inline bool dax_write_cache_enabled(struct dax_device *dax_dev) { return false; } +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