From patchwork Mon Oct 21 21:19:43 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Mahoney X-Patchwork-Id: 3079661 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 07B099F372 for ; Mon, 21 Oct 2013 21:21:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 352BC2026F for ; Mon, 21 Oct 2013 21:21:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57BAB203E9 for ; Mon, 21 Oct 2013 21:21:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752391Ab3JUVUm (ORCPT ); Mon, 21 Oct 2013 17:20:42 -0400 Received: from cantor2.suse.de ([195.135.220.15]:46361 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751826Ab3JUVUl (ORCPT ); Mon, 21 Oct 2013 17:20:41 -0400 Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 019DFA60F7 for ; Mon, 21 Oct 2013 23:20:40 +0200 (CEST) Message-Id: <20131021212006.630782497@suse.com> User-Agent: quilt/0.60-5.1.1 Date: Mon, 21 Oct 2013 17:19:43 -0400 From: Jeff Mahoney To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.com Subject: [patch 03/13] btrfs: publish supported featured in sysfs References: <20131021211940.432195222@suse.com> Content-Disposition: inline; filename=patches.suse/btrfs-publish-supported-featured-in-sysfs Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds the ability to publish supported features to sysfs under /sys/fs/btrfs/features. The files are module-wide and export which features the kernel supports. The content, for now, is just "0\n". Signed-off-by: Jeff Mahoney --- fs/btrfs/sysfs.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/sysfs.h | 43 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 87 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/fs/btrfs/sysfs.c 2013-10-21 16:09:52.760201346 -0400 +++ b/fs/btrfs/sysfs.c 2013-10-21 16:09:59.816046422 -0400 @@ -26,20 +26,64 @@ #include "ctree.h" #include "disk-io.h" #include "transaction.h" +#include "sysfs.h" + +static ssize_t btrfs_feature_attr_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "0\n"); +} + +BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF); +BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL); +BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS); +BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO); +BTRFS_FEAT_ATTR_INCOMPAT(compress_lzov2, COMPRESS_LZOv2); +BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA); +BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF); +BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56); +BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA); + +static struct attribute *btrfs_supported_feature_attrs[] = { + BTRFS_FEAT_ATTR_PTR(mixed_backref), + BTRFS_FEAT_ATTR_PTR(default_subvol), + BTRFS_FEAT_ATTR_PTR(mixed_groups), + BTRFS_FEAT_ATTR_PTR(compress_lzo), + BTRFS_FEAT_ATTR_PTR(compress_lzov2), + BTRFS_FEAT_ATTR_PTR(big_metadata), + BTRFS_FEAT_ATTR_PTR(extended_iref), + BTRFS_FEAT_ATTR_PTR(raid56), + BTRFS_FEAT_ATTR_PTR(skinny_metadata), + NULL +}; + +static const struct attribute_group btrfs_feature_attr_group = { + .name = "features", + .attrs = btrfs_supported_feature_attrs, +}; /* /sys/fs/btrfs/ entry */ static struct kset *btrfs_kset; int btrfs_init_sysfs(void) { + int ret; btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj); if (!btrfs_kset) return -ENOMEM; + + ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); + if (ret) { + kset_unregister(btrfs_kset); + return ret; + } + return 0; } void btrfs_exit_sysfs(void) { + sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group); kset_unregister(btrfs_kset); } --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ b/fs/btrfs/sysfs.h 2013-10-21 16:09:59.816046422 -0400 @@ -0,0 +1,43 @@ +#ifndef _BTRFS_SYSFS_H_ +#define _BTRFS_SYSFS_H_ + +enum btrfs_feature_set { + FEAT_COMPAT, + FEAT_COMPAT_RO, + FEAT_INCOMPAT, + FEAT_MAX +}; + +#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \ +{ \ + .attr = { .name = __stringify(_name), .mode = _mode }, \ + .show = _show, \ + .store = _store, \ +} + +struct btrfs_feature_attr { + struct kobj_attribute kobj_attr; + enum btrfs_feature_set feature_set; + u64 feature_bit; +}; + +#define BTRFS_FEAT_ATTR(_name, _feature_set, _prefix, _feature_bit) \ +static struct btrfs_feature_attr btrfs_attr_##_name = { \ + .kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \ + btrfs_feature_attr_show, NULL), \ + .feature_set = _feature_set, \ + .feature_bit = _prefix ##_## _feature_bit, \ +} +#define BTRFS_FEAT_ATTR_PTR(_name) (&btrfs_attr_##_name.kobj_attr.attr) + +#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature) +#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT, feature) +#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \ + BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature) + +/* convert from attribute */ +#define to_btrfs_feature_attr(a) \ + container_of(a, struct btrfs_feature_attr, kobj_attr) +#endif /* _BTRFS_SYSFS_H_ */