From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:46112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ghFB0-000401-T7 for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:49:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ghFAy-0007JQ-AA for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:49:50 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47468) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ghFAw-0007GK-D5 for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:49:48 -0500 From: Pankaj Gupta Date: Wed, 9 Jan 2019 20:17:35 +0530 Message-Id: <20190109144736.17452-5-pagupta@redhat.com> In-Reply-To: <20190109144736.17452-1-pagupta@redhat.com> References: <20190109144736.17452-1-pagupta@redhat.com> Subject: [Qemu-devel] [PATCH v3 4/5] ext4: disable map_sync for virtio pmem List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, qemu-devel@nongnu.org, linux-nvdimm@ml01.01.org, linux-fsdevel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-acpi@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org Cc: jack@suse.cz, stefanha@redhat.com, dan.j.williams@intel.com, riel@surriel.com, nilal@redhat.com, kwolf@redhat.com, pbonzini@redhat.com, zwisler@kernel.org, vishal.l.verma@intel.com, dave.jiang@intel.com, david@redhat.com, jmoyer@redhat.com, xiaoguangrong.eric@gmail.com, hch@infradead.org, mst@redhat.com, jasowang@redhat.com, lcapitulino@redhat.com, imammedo@redhat.com, eblake@redhat.com, willy@infradead.org, tytso@mit.edu, adilger.kernel@dilger.ca, darrick.wong@oracle.com, rjw@rjwysocki.net, pagupta@redhat.com Virtio pmem provides asynchronous host page cache flush mechanism. We don't support 'MAP_SYNC' with virtio pmem and ext4. Signed-off-by: Pankaj Gupta --- fs/ext4/file.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 69d65d4..e54f48b 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -360,8 +360,10 @@ static const struct vm_operations_struct ext4_file_vm_ops = { static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) { struct inode *inode = file->f_mapping->host; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + struct dax_device *dax_dev = sbi->s_daxdev; - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(sbi))) return -EIO; /* @@ -371,6 +373,13 @@ static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) if (!IS_DAX(file_inode(file)) && (vma->vm_flags & VM_SYNC)) return -EOPNOTSUPP; + /* We don't support synchronous mappings with guest direct access + * and virtio based host page cache flush mechanism. + */ + if (IS_DAX(file_inode(file)) && virtio_pmem_host_cache_enabled(dax_dev) + && (vma->vm_flags & VM_SYNC)) + return -EOPNOTSUPP; + file_accessed(file); if (IS_DAX(file_inode(file))) { vma->vm_ops = &ext4_dax_vm_ops; -- 2.9.3