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GET /api/1.2/patches/829942/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 829942,
    "url": "http://patchwork.ozlabs.org/api/1.2/patches/829942/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/linux-ext4/patch/20171024152415.22864-18-jack@suse.cz/",
    "project": {
        "id": 8,
        "url": "http://patchwork.ozlabs.org/api/1.2/projects/8/?format=api",
        "name": "Linux ext4 filesystem development",
        "link_name": "linux-ext4",
        "list_id": "linux-ext4.vger.kernel.org",
        "list_email": "linux-ext4@vger.kernel.org",
        "web_url": null,
        "scm_url": null,
        "webscm_url": null,
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<20171024152415.22864-18-jack@suse.cz>",
    "list_archive_url": null,
    "date": "2017-10-24T15:24:14",
    "name": "[17/17] xfs: support for synchronous DAX faults",
    "commit_ref": null,
    "pull_url": null,
    "state": "superseded",
    "archived": true,
    "hash": "57a98c6d01124ad3e817042378ca683e0a2a15fa",
    "submitter": {
        "id": 363,
        "url": "http://patchwork.ozlabs.org/api/1.2/people/363/?format=api",
        "name": "Jan Kara",
        "email": "jack@suse.cz"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/linux-ext4/patch/20171024152415.22864-18-jack@suse.cz/mbox/",
    "series": [
        {
            "id": 10008,
            "url": "http://patchwork.ozlabs.org/api/1.2/series/10008/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linux-ext4/list/?series=10008",
            "date": "2017-10-24T15:23:57",
            "name": "dax, ext4, xfs: Synchronous page faults",
            "version": 5,
            "mbox": "http://patchwork.ozlabs.org/series/10008/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/829942/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/829942/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<linux-ext4-owner@vger.kernel.org>",
        "X-Original-To": "patchwork-incoming@ozlabs.org",
        "Delivered-To": "patchwork-incoming@ozlabs.org",
        "Authentication-Results": "ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=linux-ext4-owner@vger.kernel.org;\n\treceiver=<UNKNOWN>)",
        "Received": [
            "from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3yLxtV6vQ0z9t2c\n\tfor <patchwork-incoming@ozlabs.org>;\n\tWed, 25 Oct 2017 02:25:54 +1100 (AEDT)",
            "(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S932489AbdJXPZw (ORCPT <rfc822;patchwork-incoming@ozlabs.org>);\n\tTue, 24 Oct 2017 11:25:52 -0400",
            "from mx2.suse.de ([195.135.220.15]:36150 \"EHLO mx2.suse.de\"\n\trhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP\n\tid S932431AbdJXPZf (ORCPT <rfc822;linux-ext4@vger.kernel.org>);\n\tTue, 24 Oct 2017 11:25:35 -0400",
            "from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254])\n\tby mx2.suse.de (Postfix) with ESMTP id 54C55AE18;\n\tTue, 24 Oct 2017 15:25:28 +0000 (UTC)",
            "by quack2.suse.cz (Postfix, from userid 1000)\n\tid 76DCA1E35DA; Tue, 24 Oct 2017 17:25:27 +0200 (CEST)"
        ],
        "X-Virus-Scanned": "by amavisd-new at test-mx.suse.de",
        "From": "Jan Kara <jack@suse.cz>",
        "To": "Dan Williams <dan.j.williams@intel.com>",
        "Cc": "Ross Zwisler <ross.zwisler@linux.intel.com>,\n\tChristoph Hellwig <hch@infradead.org>,\n\t<linux-ext4@vger.kernel.org>, linux-nvdimm@lists.01.org,\n\t<linux-fsdevel@vger.kernel.org>, <linux-xfs@vger.kernel.org>,\n\tlinux-api@vger.kernel.org, <linux-mm@kvack.org>,\n\tChristoph Hellwig <hch@lst.de>, Jan Kara <jack@suse.cz>",
        "Subject": "[PATCH 17/17] xfs: support for synchronous DAX faults",
        "Date": "Tue, 24 Oct 2017 17:24:14 +0200",
        "Message-Id": "<20171024152415.22864-18-jack@suse.cz>",
        "X-Mailer": "git-send-email 2.12.3",
        "In-Reply-To": "<20171024152415.22864-1-jack@suse.cz>",
        "References": "<20171024152415.22864-1-jack@suse.cz>",
        "Sender": "linux-ext4-owner@vger.kernel.org",
        "Precedence": "bulk",
        "List-ID": "<linux-ext4.vger.kernel.org>",
        "X-Mailing-List": "linux-ext4@vger.kernel.org"
    },
    "content": "From: Christoph Hellwig <hch@lst.de>\n\nReturn IOMAP_F_DIRTY from xfs_file_iomap_begin() when asked to prepare\nblocks for writing and the inode is pinned, and has dirty fields other\nthan the timestamps.  In __xfs_filemap_fault() we then detect this case\nand call dax_finish_sync_fault() to make sure all metadata is committed,\nand to insert the page table entry.\n\nNote that this will also dirty corresponding radix tree entry which is\nwhat we want - fsync(2) will still provide data integrity guarantees for\napplications not using userspace flushing. And applications using\nuserspace flushing can avoid calling fsync(2) and thus avoid the\nperformance overhead.\n\n[JK: Added VM_SYNC flag handling]\n\nSigned-off-by: Christoph Hellwig <hch@lst.de>\nSigned-off-by: Jan Kara <jack@suse.cz>\n---\n fs/xfs/xfs_file.c  | 15 ++++++++++++++-\n fs/xfs/xfs_iomap.c |  5 +++++\n 2 files changed, 19 insertions(+), 1 deletion(-)",
    "diff": "diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c\nindex 7c6b8def6eed..02093df4b314 100644\n--- a/fs/xfs/xfs_file.c\n+++ b/fs/xfs/xfs_file.c\n@@ -44,6 +44,7 @@\n #include <linux/falloc.h>\n #include <linux/pagevec.h>\n #include <linux/backing-dev.h>\n+#include <linux/mman.h>\n \n static const struct vm_operations_struct xfs_file_vm_ops;\n \n@@ -1040,7 +1041,11 @@ __xfs_filemap_fault(\n \n \txfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);\n \tif (IS_DAX(inode)) {\n-\t\tret = dax_iomap_fault(vmf, pe_size, NULL, &xfs_iomap_ops);\n+\t\tpfn_t pfn;\n+\n+\t\tret = dax_iomap_fault(vmf, pe_size, &pfn, &xfs_iomap_ops);\n+\t\tif (ret & VM_FAULT_NEEDDSYNC)\n+\t\t\tret = dax_finish_sync_fault(vmf, pe_size, pfn);\n \t} else {\n \t\tif (write_fault)\n \t\t\tret = iomap_page_mkwrite(vmf, &xfs_iomap_ops);\n@@ -1131,6 +1136,13 @@ xfs_file_mmap(\n \tstruct file\t*filp,\n \tstruct vm_area_struct *vma)\n {\n+\t/*\n+\t * We don't support synchronous mappings for non-DAX files. At least\n+\t * until someone comes with a sensible use case.\n+\t */\n+\tif (!IS_DAX(file_inode(filp)) && (vma->vm_flags & VM_SYNC))\n+\t\treturn -EOPNOTSUPP;\n+\n \tfile_accessed(filp);\n \tvma->vm_ops = &xfs_file_vm_ops;\n \tif (IS_DAX(file_inode(filp)))\n@@ -1149,6 +1161,7 @@ const struct file_operations xfs_file_operations = {\n \t.compat_ioctl\t= xfs_file_compat_ioctl,\n #endif\n \t.mmap\t\t= xfs_file_mmap,\n+\t.mmap_supported_flags = MAP_SYNC,\n \t.open\t\t= xfs_file_open,\n \t.release\t= xfs_file_release,\n \t.fsync\t\t= xfs_file_fsync,\ndiff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c\nindex f179bdf1644d..b43be199fbdf 100644\n--- a/fs/xfs/xfs_iomap.c\n+++ b/fs/xfs/xfs_iomap.c\n@@ -33,6 +33,7 @@\n #include \"xfs_error.h\"\n #include \"xfs_trans.h\"\n #include \"xfs_trans_space.h\"\n+#include \"xfs_inode_item.h\"\n #include \"xfs_iomap.h\"\n #include \"xfs_trace.h\"\n #include \"xfs_icache.h\"\n@@ -1086,6 +1087,10 @@ xfs_file_iomap_begin(\n \t\ttrace_xfs_iomap_found(ip, offset, length, 0, &imap);\n \t}\n \n+\tif ((flags & IOMAP_WRITE) && xfs_ipincount(ip) &&\n+\t    (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))\n+\t\tiomap->flags |= IOMAP_F_DIRTY;\n+\n \txfs_bmbt_to_iomap(ip, iomap, &imap);\n \n \tif (shared)\n",
    "prefixes": [
        "17/17"
    ]
}