| Message ID | 1388729434-19799-2-git-send-email-quwenruo@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 3 January 2014 06:10, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote: > Btrfs can be remounted without barrier, but there is no "barrier" option > so nobody can remount btrfs back with barrier on. Only umount and > mount again can re-enable barrier.(Quite awkward) > > Also the mount options in the document is also changed slightly for the > further pairing options changes. > > Reported-by: Daniel Blueman <daniel@quora.org> > Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> > Cc: David Sterba <dsterba@suse.cz> > --- > changelog: > v1: Add barrier option > v2: Change the document style to fit pairing options better > --- > Documentation/filesystems/btrfs.txt | 13 +++++++------ > fs/btrfs/super.c | 8 +++++++- > 2 files changed, 14 insertions(+), 7 deletions(-) > > diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt > index 5dd282d..2d2e016 100644 > --- a/Documentation/filesystems/btrfs.txt > +++ b/Documentation/filesystems/btrfs.txt > @@ -38,7 +38,7 @@ Mount Options > ============= > > When mounting a btrfs filesystem, the following option are accepted. > -Unless otherwise specified, all options default to off. > +Options with (*) are default options and will not show in the mount options. > > alloc_start=<bytes> > Debugging option to force all block allocations above a certain > @@ -138,12 +138,13 @@ Unless otherwise specified, all options default to off. > Disable support for Posix Access Control Lists (ACLs). See the > acl(5) manual page for more information about ACLs. > > + barrier(*) > nobarrier > - Disables the use of block layer write barriers. Write barriers ensure > - that certain IOs make it through the device cache and are on persistent > - storage. If used on a device with a volatile (non-battery-backed) > - write-back cache, this option will lead to filesystem corruption on a > - system crash or power loss. > + Disable/enable the use of block layer write barriers. Write barriers Please use "Enable/Disable ..." to match order on the options barrier(*) then nobarrier immediately above. > + ensure that certain IOs make it through the device cache and are on > + persistent storage. If used on a device with a volatile And: "... If disabled on a device with a volatile" to make more sense when both enable and disable options are listed. > + (non-battery-backed) write-back cache, this option will lead to > + filesystem corruption on a system crash or power loss. > > nodatacow > Disable data copy-on-write for newly created files. Implies nodatasum, > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > index e9c13fb..fe9d8a6 100644 > --- a/fs/btrfs/super.c > +++ b/fs/btrfs/super.c > @@ -323,7 +323,7 @@ enum { > Opt_no_space_cache, Opt_recovery, Opt_skip_balance, > Opt_check_integrity, Opt_check_integrity_including_extent_data, > Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, > - Opt_commit_interval, > + Opt_commit_interval, Opt_barrier, > Opt_err, > }; > > @@ -335,6 +335,7 @@ static match_table_t tokens = { > {Opt_nodatasum, "nodatasum"}, > {Opt_nodatacow, "nodatacow"}, > {Opt_nobarrier, "nobarrier"}, > + {Opt_barrier, "barrier"}, > {Opt_max_inline, "max_inline=%s"}, > {Opt_alloc_start, "alloc_start=%s"}, > {Opt_thread_pool, "thread_pool=%d"}, > @@ -494,6 +495,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) > btrfs_clear_opt(info->mount_opt, SSD); > btrfs_clear_opt(info->mount_opt, SSD_SPREAD); > break; > + case Opt_barrier: > + if (btrfs_test_opt(root, NOBARRIER)) > + btrfs_info(root->fs_info, "turning on barriers"); > + btrfs_clear_opt(info->mount_opt, NOBARRIER); > + break; > case Opt_nobarrier: > btrfs_info(root->fs_info, "turning off barriers"); > btrfs_set_opt(info->mount_opt, NOBARRIER); > -- > 1.8.5.2 > Thanks, Mike -- 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
On fri, 3 Jan 2014 08:44:30 +0000, Mike Fleetwood wrote: > On 3 January 2014 06:10, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote: >> Btrfs can be remounted without barrier, but there is no "barrier" option >> so nobody can remount btrfs back with barrier on. Only umount and >> mount again can re-enable barrier.(Quite awkward) >> >> Also the mount options in the document is also changed slightly for the >> further pairing options changes. >> >> Reported-by: Daniel Blueman <daniel@quora.org> >> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> >> Cc: David Sterba <dsterba@suse.cz> >> --- >> changelog: >> v1: Add barrier option >> v2: Change the document style to fit pairing options better >> --- >> Documentation/filesystems/btrfs.txt | 13 +++++++------ >> fs/btrfs/super.c | 8 +++++++- >> 2 files changed, 14 insertions(+), 7 deletions(-) >> >> diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt >> index 5dd282d..2d2e016 100644 >> --- a/Documentation/filesystems/btrfs.txt >> +++ b/Documentation/filesystems/btrfs.txt >> @@ -38,7 +38,7 @@ Mount Options >> ============= >> >> When mounting a btrfs filesystem, the following option are accepted. >> -Unless otherwise specified, all options default to off. >> +Options with (*) are default options and will not show in the mount options. >> >> alloc_start=<bytes> >> Debugging option to force all block allocations above a certain >> @@ -138,12 +138,13 @@ Unless otherwise specified, all options default to off. >> Disable support for Posix Access Control Lists (ACLs). See the >> acl(5) manual page for more information about ACLs. >> >> + barrier(*) >> nobarrier >> - Disables the use of block layer write barriers. Write barriers ensure >> - that certain IOs make it through the device cache and are on persistent >> - storage. If used on a device with a volatile (non-battery-backed) >> - write-back cache, this option will lead to filesystem corruption on a >> - system crash or power loss. >> + Disable/enable the use of block layer write barriers. Write barriers > Please use > "Enable/Disable ..." > to match order on the options barrier(*) then nobarrier immediately above. > >> + ensure that certain IOs make it through the device cache and are on >> + persistent storage. If used on a device with a volatile > And: > "... If disabled on a device with a volatile" > to make more sense when both enable and disable options are listed. Thanks for pointing out the problem. I'll fix it soon. Qu >> + (non-battery-backed) write-back cache, this option will lead to >> + filesystem corruption on a system crash or power loss. >> >> nodatacow >> Disable data copy-on-write for newly created files. Implies nodatasum, >> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c >> index e9c13fb..fe9d8a6 100644 >> --- a/fs/btrfs/super.c >> +++ b/fs/btrfs/super.c >> @@ -323,7 +323,7 @@ enum { >> Opt_no_space_cache, Opt_recovery, Opt_skip_balance, >> Opt_check_integrity, Opt_check_integrity_including_extent_data, >> Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, >> - Opt_commit_interval, >> + Opt_commit_interval, Opt_barrier, >> Opt_err, >> }; >> >> @@ -335,6 +335,7 @@ static match_table_t tokens = { >> {Opt_nodatasum, "nodatasum"}, >> {Opt_nodatacow, "nodatacow"}, >> {Opt_nobarrier, "nobarrier"}, >> + {Opt_barrier, "barrier"}, >> {Opt_max_inline, "max_inline=%s"}, >> {Opt_alloc_start, "alloc_start=%s"}, >> {Opt_thread_pool, "thread_pool=%d"}, >> @@ -494,6 +495,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) >> btrfs_clear_opt(info->mount_opt, SSD); >> btrfs_clear_opt(info->mount_opt, SSD_SPREAD); >> break; >> + case Opt_barrier: >> + if (btrfs_test_opt(root, NOBARRIER)) >> + btrfs_info(root->fs_info, "turning on barriers"); >> + btrfs_clear_opt(info->mount_opt, NOBARRIER); >> + break; >> case Opt_nobarrier: >> btrfs_info(root->fs_info, "turning off barriers"); >> btrfs_set_opt(info->mount_opt, NOBARRIER); >> -- >> 1.8.5.2 >> > Thanks, > Mike > -- > 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 > -- 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
diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt index 5dd282d..2d2e016 100644 --- a/Documentation/filesystems/btrfs.txt +++ b/Documentation/filesystems/btrfs.txt @@ -38,7 +38,7 @@ Mount Options ============= When mounting a btrfs filesystem, the following option are accepted. -Unless otherwise specified, all options default to off. +Options with (*) are default options and will not show in the mount options. alloc_start=<bytes> Debugging option to force all block allocations above a certain @@ -138,12 +138,13 @@ Unless otherwise specified, all options default to off. Disable support for Posix Access Control Lists (ACLs). See the acl(5) manual page for more information about ACLs. + barrier(*) nobarrier - Disables the use of block layer write barriers. Write barriers ensure - that certain IOs make it through the device cache and are on persistent - storage. If used on a device with a volatile (non-battery-backed) - write-back cache, this option will lead to filesystem corruption on a - system crash or power loss. + Disable/enable the use of block layer write barriers. Write barriers + ensure that certain IOs make it through the device cache and are on + persistent storage. If used on a device with a volatile + (non-battery-backed) write-back cache, this option will lead to + filesystem corruption on a system crash or power loss. nodatacow Disable data copy-on-write for newly created files. Implies nodatasum, diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index e9c13fb..fe9d8a6 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -323,7 +323,7 @@ enum { Opt_no_space_cache, Opt_recovery, Opt_skip_balance, Opt_check_integrity, Opt_check_integrity_including_extent_data, Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, - Opt_commit_interval, + Opt_commit_interval, Opt_barrier, Opt_err, }; @@ -335,6 +335,7 @@ static match_table_t tokens = { {Opt_nodatasum, "nodatasum"}, {Opt_nodatacow, "nodatacow"}, {Opt_nobarrier, "nobarrier"}, + {Opt_barrier, "barrier"}, {Opt_max_inline, "max_inline=%s"}, {Opt_alloc_start, "alloc_start=%s"}, {Opt_thread_pool, "thread_pool=%d"}, @@ -494,6 +495,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) btrfs_clear_opt(info->mount_opt, SSD); btrfs_clear_opt(info->mount_opt, SSD_SPREAD); break; + case Opt_barrier: + if (btrfs_test_opt(root, NOBARRIER)) + btrfs_info(root->fs_info, "turning on barriers"); + btrfs_clear_opt(info->mount_opt, NOBARRIER); + break; case Opt_nobarrier: btrfs_info(root->fs_info, "turning off barriers"); btrfs_set_opt(info->mount_opt, NOBARRIER);
Btrfs can be remounted without barrier, but there is no "barrier" option so nobody can remount btrfs back with barrier on. Only umount and mount again can re-enable barrier.(Quite awkward) Also the mount options in the document is also changed slightly for the further pairing options changes. Reported-by: Daniel Blueman <daniel@quora.org> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Cc: David Sterba <dsterba@suse.cz> --- changelog: v1: Add barrier option v2: Change the document style to fit pairing options better --- Documentation/filesystems/btrfs.txt | 13 +++++++------ fs/btrfs/super.c | 8 +++++++- 2 files changed, 14 insertions(+), 7 deletions(-)