From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ryusuke Konishi Subject: Re: [PATCH 4/4] nilfs2: add norepair mount option Date: Fri, 20 Nov 2009 04:10:11 +0900 (JST) Message-ID: <20091120.041011.123624190.ryusuke@osrg.net> References: <1258650553-10743-5-git-send-email-konishi.ryusuke@lab.ntt.co.jp> <4B05821C.4030901@redhat.com> <20091120.031015.04647165.ryusuke@osrg.net> Reply-To: NILFS Users mailing list Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20091120.031015.04647165.ryusuke-sG5X7nlA6pw@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: users-bounces-JrjvKiOkagjYtjvyW6yDsg@public.gmane.org Errors-To: users-bounces-JrjvKiOkagjYtjvyW6yDsg@public.gmane.org To: users-JrjvKiOkagjYtjvyW6yDsg@public.gmane.org, sandeen-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: jan.de.kruyf-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, konishi.ryusuke-Zyj7fXuS5i5L9jVzuh4AOg@public.gmane.org On Fri, 20 Nov 2009 03:10:15 +0900 (JST), Ryusuke Konishi wrote: > Hi, > On Thu, 19 Nov 2009 11:36:28 -0600, Eric Sandeen wrote: > > Ryusuke Konishi wrote: > > > This adds norepair mount option that allows users to avoid temporal > > > write access to a read-only mount or snapshots during mount/recovery. > > > Without this option, write access will be even performed for those > > > types of mounts; the temporal write access is needed to mount root > > > file system read-only after an unclean shutdown. > > > > > > This option is useful for users to avoid any write access on the > > > device. > > > > For what it's worth, ext3 & ext4 just added a "norecovery" option as > > an alias to "noload" which skips journal replay; xfs already has > > "norecovery" - so if you wish to be consistent with ext3/ext4/xfs, > > "norecovery" may be a good choice for the option? > > > > Thanks, > > -Eric > > Thank you! OK, I'll take your advice. > > Ryusuke Here is a revised version. I also fixed that the previous patch did not support "show option" interface. Thanks, Ryusuke Konishi -- Author: Ryusuke Konishi Date: Fri Nov 20 03:28:01 2009 +0900 nilfs2: add norecovery mount option This adds "norecovery" mount option which disables temporal write access to read-only mounts or snapshots during mount/recovery. Without this option, write access will be even performed for those types of mounts; the temporal write access is needed to mount root file system read-only after an unclean shutdown. This option will be helpful when user wants to prevent any write access to the device. Signed-off-by: Ryusuke Konishi Cc: Eric Sandeen diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt index cbd8779..4949fca 100644 --- a/Documentation/filesystems/nilfs2.txt +++ b/Documentation/filesystems/nilfs2.txt @@ -70,6 +70,10 @@ order=strict Apply strict in-order semantics that preserves sequence blocks. That means, it is guaranteed that no overtaking of events occurs in the recovered file system after a crash. +norecovery Disable recovery of the filesystem on mount. + This disables every write access on the device for + read-only mounts or snapshots. This option will fail + for r/w mounts on an unclean volume. NILFS2 usage ============ diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 990ead4..5403b3e 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -479,6 +479,8 @@ static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs) seq_printf(seq, ",errors=panic"); if (nilfs_test_opt(sbi, STRICT_ORDER)) seq_printf(seq, ",order=strict"); + if (nilfs_test_opt(sbi, NORECOVERY)) + seq_printf(seq, ",norecovery"); return 0; } @@ -547,7 +549,7 @@ static const struct export_operations nilfs_export_ops = { enum { Opt_err_cont, Opt_err_panic, Opt_err_ro, - Opt_nobarrier, Opt_snapshot, Opt_order, + Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, Opt_err, }; @@ -558,6 +560,7 @@ static match_table_t tokens = { {Opt_nobarrier, "nobarrier"}, {Opt_snapshot, "cp=%u"}, {Opt_order, "order=%s"}, + {Opt_norecovery, "norecovery"}, {Opt_err, NULL} }; @@ -608,6 +611,9 @@ static int parse_options(char *options, struct super_block *sb) sbi->s_snapshot_cno = option; nilfs_set_opt(sbi, SNAPSHOT); break; + case Opt_norecovery: + nilfs_set_opt(sbi, NORECOVERY); + break; default: printk(KERN_ERR "NILFS: Unrecognized mount option \"%s\"\n", p); @@ -863,6 +869,14 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data) goto restore_opts; } + if (!nilfs_valid_fs(nilfs)) { + printk(KERN_WARNING "NILFS (device %s): couldn't " + "remount because the filesystem is in an " + "incomplete recovery state.\n", sb->s_id); + err = -EINVAL; + goto restore_opts; + } + if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) goto out; if (*flags & MS_RDONLY) { diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 890a8d3..6241e17 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -264,8 +264,14 @@ int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) int valid_fs = nilfs_valid_fs(nilfs); int err; - if (nilfs_loaded(nilfs)) - return 0; + if (nilfs_loaded(nilfs)) { + if (valid_fs || + ((s_flags & MS_RDONLY) && nilfs_test_opt(sbi, NORECOVERY))) + return 0; + printk(KERN_ERR "NILFS: the filesystem is in an incomplete " + "recovery state.\n"); + return -EINVAL; + } if (!valid_fs) { printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n"); @@ -295,6 +301,11 @@ int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) goto skip_recovery; if (s_flags & MS_RDONLY) { + if (nilfs_test_opt(sbi, NORECOVERY)) { + printk(KERN_INFO "NILFS: norecovery option specified. " + "skipping roll-forward recovery\n"); + goto skip_recovery; + } if (really_read_only) { printk(KERN_ERR "NILFS: write access " "unavailable, cannot proceed.\n"); @@ -302,6 +313,11 @@ int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) goto failed_unload; } sbi->s_super->s_flags &= ~MS_RDONLY; + } else if (nilfs_test_opt(sbi, NORECOVERY)) { + printk(KERN_ERR "NILFS: recovery cancelled because norecovery " + "option was specified for a read/write mount\n"); + err = -EINVAL; + goto failed_unload; } err = nilfs_recover_logical_segments(nilfs, sbi, &ri); diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h index 72289d2..3fe02cf 100644 --- a/include/linux/nilfs2_fs.h +++ b/include/linux/nilfs2_fs.h @@ -151,6 +151,8 @@ struct nilfs_super_root { #define NILFS_MOUNT_BARRIER 0x1000 /* Use block barriers */ #define NILFS_MOUNT_STRICT_ORDER 0x2000 /* Apply strict in-order semantics also for data */ +#define NILFS_MOUNT_NORECOVERY 0x4000 /* Disable write access during + mount-time recovery */ /**