[PATCH] Btrfs: make delayed ref lock logic more readable
Locking and unlocking delayed ref mutex are in the different functions,
and the name of lock functions is not uniform, so the readability is not
so good, this patch optimizes the lock logic and makes it more readable.
Signed-off-by: Miao Xie mi...@cn.fujitsu.com
---
fs/btrfs/delayed-ref.c | 8
fs/btrfs/delayed-ref.h | 6 ++
fs/btrfs/extent-tree.c | 42 --
3 files changed, 38 insertions(+), 18 deletions(-)
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 455894f..b7a0641 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -426,6 +426,14 @@ again:
return 1;
}
+void btrfs_release_ref_cluster(struct list_head *cluster)
+{
+ struct list_head *pos, *q;
+
+ list_for_each_safe(pos, q, cluster)
+ list_del_init(pos);
+}
+
/*
* helper function to update an extent delayed ref in the
* rbtree. existing and update must both have the same
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index fe50392..7939149 100644
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -211,8 +211,14 @@ struct btrfs_delayed_ref_head *
btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr);
int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans,
struct btrfs_delayed_ref_head *head);
+static inline void btrfs_delayed_ref_unlock(struct btrfs_delayed_ref_head
*head)
+{
+ mutex_unlock(head-mutex);
+}
+
int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans,
struct list_head *cluster, u64 search_start);
+void btrfs_release_ref_cluster(struct list_head *cluster);
int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_root *delayed_refs,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index ae3c24a..b6ed965 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2143,7 +2143,6 @@ static int run_one_delayed_ref(struct btrfs_trans_handle
*trans,
node-num_bytes);
}
}
- mutex_unlock(head-mutex);
return ret;
}
@@ -2258,7 +2257,7 @@ static noinline int run_clustered_refs(struct
btrfs_trans_handle *trans,
* process of being added. Don't run this ref yet.
*/
list_del_init(locked_ref-cluster);
- mutex_unlock(locked_ref-mutex);
+ btrfs_delayed_ref_unlock(locked_ref);
locked_ref = NULL;
delayed_refs-num_heads_ready++;
spin_unlock(delayed_refs-lock);
@@ -2297,25 +2296,22 @@ static noinline int run_clustered_refs(struct
btrfs_trans_handle *trans,
btrfs_free_delayed_extent_op(extent_op);
if (ret) {
- list_del_init(locked_ref-cluster);
- mutex_unlock(locked_ref-mutex);
-
- printk(KERN_DEBUG btrfs:
run_delayed_extent_op returned %d\n, ret);
+ printk(KERN_DEBUG
+ btrfs: run_delayed_extent_op
+ returned %d\n, ret);
spin_lock(delayed_refs-lock);
+ btrfs_delayed_ref_unlock(locked_ref);
return ret;
}
goto next;
}
-
- list_del_init(locked_ref-cluster);
- locked_ref = NULL;
}
ref-in_tree = 0;
rb_erase(ref-rb_node, delayed_refs-root);
delayed_refs-num_entries--;
- if (locked_ref) {
+ if (!btrfs_delayed_ref_is_head(ref)) {
/*
* when we play the delayed ref, also correct the
* ref_mod on head
@@ -2337,20 +2333,29 @@ static noinline int run_clustered_refs(struct
btrfs_trans_handle *trans,
ret = run_one_delayed_ref(trans, root, ref, extent_op,
must_insert_reserved);
- btrfs_put_delayed_ref(ref);
btrfs_free_delayed_extent_op(extent_op);
- count++;
-
if (ret) {
- if (locked_ref) {
- list_del_init(locked_ref-cluster);
- mutex_unlock(locked_ref-mutex);
- }
- printk(KERN_DEBUG btrfs: run_one_delayed_ref returned
%d\n, ret);
+
Re: Feeback on RAID1 feature of Btrfs
On Tue, Dec 18, 2012 at 6:13 AM, Hugo Mills h...@carfax.org.uk wrote:
On Tue, Dec 18, 2012 at 01:20:20PM +0200, Brendan Hide wrote:
On 2012/12/17 06:23 PM, Hugo Mills wrote:
On Mon, Dec 17, 2012 at 04:51:33PM +0100, Sebastien Luttringer wrote:
Hello,
snip
I get the feeling that RAID1 only allow one disk removing. Which is more
a RAID5 feature.
The RAID-1 support in btrfs makes exactly two copies of each item
of data, so you can lose at most one disk from the array safely. Lose
any more, and you're likely to have lost data, as you've found out.
I'm afraid Btrfs raid1 will not be working before the end of the world.
It does work (as you demonstrated with the first disk being
removed) -- but just not as you thought it should. Now, you can argue
that RAID-1 isn't a good name to use here, but there's no good name
in RAID terminology to describe what we actually have here.
Technically, btrfs's RAID1 implementation is much closer to RAID1E
than traditional RAID1. See
http://en.wikipedia.org/wiki/Non-standard_RAID_levels#RAID_1E or
http://pic.dhe.ibm.com/infocenter/director/v5r2/index.jsp?topic=/serveraid_9.00/fqy0_craid1e.html
Perhaps a new name, as with ZFS, might be appropriate. RAID-Z and
RAID-Z2, for example, could not adequately be described by any
existing RAID terminology and, technically, RAID-Z still isn't a
RAID in the classical sense.
Yeah, we did have a naming scheme proposed, with combinations of
nCmSpP, where n is the number of copies held, m the number of stripes,
and p the number of parity stripes. So btrfs RAID-1 is 2C, RAID-5 on 5
disks would be 4S1P, and RAID-10 on 4 disks would be 2C2S.
...yes. something like this is not only reflects reality better,, and
actually transfers information in consistent way (vs RAID-XYZ...
meaningless ENUM!) you could maybe do something like:
2C2S : -1S : 0
...or similar, showing:
{normal}
{OFFSET max degraded [rel boundary]}
{OFFSET current}
... which instantly makes the useful boundaries known, along with the
active panic level i should be experiencing :)
I'd prefer
to see that than some non-standard RAID-18KTHXBYE formulation.
^^^ this. the term RAID conjures expectations that run afoul of
btrfs's reality and should thus simply be avoided altogether
IMO, unless you wish/must explicitly correlate some similarity X,
there is no need to even mention the work RAID, because it carries no
information.
--
C Anthony
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About btrfs qgroup import/export command
Hi, everyone. As we know, there is no backup function for qgroup. when the problem occurs, the users must recover qgroup configuration manually, it is not convenient. And besides that, some users might want to import an existed qgroup configuration into a new filesystem. Btrfs does not have such a function,it can only be done manually. So we want to implement btrfs qgroup import/export commands. 1)'btrfs qgroup export' commands will export qgroup tree into a user's specified file.(stdout by default) 2)user may modify the configuration file firstly and then import it into the filesystem.(by 'btrfs qgroup import' command) The file may be formated as the following: Qgroupid is_compressed is_exclusive limited_sizeparent -- 0/10 0 10G1/0 1/01 1 20G--- If 'is_exclusive' is set, 'limited_size' corresponds to max exlusive size, else max referenced size. Here 'parent' exclude ancestral qgroups. Is there any comment about this idea? Thanks Miao -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: About btrfs qgroup import/export command
On 19.12.2012 12:25, Miao Xie wrote: Hi, everyone. As we know, there is no backup function for qgroup. when the problem occurs, the users must recover qgroup configuration manually, it is not convenient. And besides that, some users might want to import an existed qgroup configuration into a new filesystem. Btrfs does not have such a function,it can only be done manually. So we want to implement btrfs qgroup import/export commands. 1)'btrfs qgroup export' commands will export qgroup tree into a user's specified file.(stdout by default) 2)user may modify the configuration file firstly and then import it into the filesystem.(by 'btrfs qgroup import' command) The file may be formated as the following: Qgroupid is_compressed is_exclusive limited_sizeparent -- 0/10 0 10G1/0 1/01 1 20G--- If 'is_exclusive' is set, 'limited_size' corresponds to max exlusive size, else max referenced size. Here 'parent' exclude ancestral qgroups. Is there any comment about this idea? The configuration only really makes sense in combination with the existing subvolumes. Even if the target has subvolumes under the same name, they might have different internal IDs. So it might make more sense to address the level 0 qgroups by name. Also it might be misleading to apply a configuration to an existing fs, as it currently is not possible get a correct accounting if the fs is not empty. Rescan is not yet implemented. So instead of just saving and restoring the qgroup config, it might make more sense to create a new filesystem including all subvolumes and quota config from a config file. But, I'm not completely convinced that this is a features that is needed frequently. If I want a standard deployment, I simple write a script that creates the fs + subvol + quota. -Arne Thanks Miao -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: BTree lock contention
On Tue, Dec 18, 2012 at 07:57:23PM +0530, Atri Sharma wrote: I am pretty weak with Mediawiki. Is there any way somebody could please place my name 'Atri Sharma' for the Btree locking contention in the wiki? Done. We're using templates for the project descriptions, and clicking 'edit' leads to editing the template itself, so one has to edit the containing section (or the whole page) instead. david -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC PATCH V6 2/2] Btrfs: Add a new ioctl to change the label of a mounted file system
On Tue, Dec 18, 2012 at 11:06:07AM +0800, Jeff Liu wrote:
+static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
+{
+ struct btrfs_root *root = BTRFS_I(fdentry(file)-d_inode)-root;
+ struct btrfs_super_block *super_block = root-fs_info-super_copy;
+ struct btrfs_trans_handle *trans;
+ char label[BTRFS_LABEL_SIZE];
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(label, arg, sizeof(label)))
+ return -EFAULT;
+
+ if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE)
+ return -EINVAL;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ mutex_lock(root-fs_info-volume_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_unlock;
+ }
+
+ strcpy(super_block-label, label);
+ btrfs_end_transaction(trans, root);
If this fails, eg. with EIO, it will not be reported back to the user
ret = btrfs_end_transaction(trans, root);
should fix it.
+
+out_unlock:
+ mutex_unlock(root-fs_info-volume_mutex);
+ mnt_drop_write_file(file);
+ return ret;
+}
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Re: BTree lock contention
On Wed, Dec 19, 2012 at 08:34:08PM +0530, Atri Sharma wrote: Sorry for bothering again, but I cant see Btree Lock contention marked as in progress or my name anywhere on https://btrfs.wiki.kernel.org/index.php/Project_ideas Could you please check? I don't know what happened to the edit, but I'm sure I moved the 'lock contention' under 'claimed projects' with your name added. Now it's there. david -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
HIT WARN_ON WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]()
Hi all, Did someone have met this problem before. When doing the tests, I hit the WARN_ON. Is this log make sense or someone had fixed the problem. If needed, I can supply the detail log and the testcase source file. Version: the latest codes at linus git tree. [ 2140.981293] use_block_rsv: 336 callbacks suppressed [ 2140.981295] [ cut here ] [ 2140.981308] WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]() [ 2140.981309] Hardware name: 2356BG6 ... [ 2140.981568] [ cut here ] [ 2140.981574] WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]() [ 2140.981574] Hardware name: 2356BG6 [ 2140.981575] btrfs: block rsv returned -28 Always this value. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: HIT WARN_ON WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]()
On Wed, Dec 19, 2012 at 9:12 AM, Rock Lee zim...@code-trick.com wrote: Hi all, Did someone have met this problem before. When doing the tests, I hit the WARN_ON. Is this log make sense or someone had fixed the problem. If needed, I can supply the detail log and the testcase source file. That'd be good, as well as the specific kernel version. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: HIT WARN_ON WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]()
On Wed, Dec 19, 2012 at 08:12:01AM -0700, Rock Lee wrote: Hi all, Did someone have met this problem before. When doing the tests, I hit the WARN_ON. Is this log make sense or someone had fixed the problem. If needed, I can supply the detail log and the testcase source file. Version: the latest codes at linus git tree. If you can give me your testcase I will love you forever. Thanks, Josef -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: HIT WARN_ON WARNING: at fs/btrfs/extent-tree.c:6339 btrfs_alloc_free_block+0x126/0x330 [btrfs]()
Hi, I just try to write the testcase a few hours before. So there will be some problems. Maybe you can ignore the unimplemented and the ugly parts. Welcome any feedback. :) I have uploaded the test source file to Github. Please open this link: https://github.com/Zimilo/btrfs-testing-suites/blob/master/fallocate/fallocate.c Latest kernel commit is 752451f01c4567b506bf4343082682dbb8fb30dd in linus git tree. Testing on a 20GB loop device. When running the second case, try to do the sync command manually at the some time several times. Always could be reproduced. You will get hit the WARN_ON, dmesg will report them. Except this problem, there's another bug, btrfs_fallocate doesn't guarantee subsequent write to that range not to fail because of disk space. 2012/12/19 Josef Bacik jba...@fusionio.com: On Wed, Dec 19, 2012 at 08:12:01AM -0700, Rock Lee wrote: Hi all, Did someone have met this problem before. When doing the tests, I hit the WARN_ON. Is this log make sense or someone had fixed the problem. If needed, I can supply the detail log and the testcase source file. Version: the latest codes at linus git tree. If you can give me your testcase I will love you forever. Thanks, Josef -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Bug: trying to create reflink on different device results in empty file
On Tue, Dec 11, 2012 at 11:16:03PM +0100, Koen De Wit wrote: When trying to create a clone (reflink) of a file on a different device, you'll get this error: Invalid cross-device link However, an empty file is created on the target location. An invalid clone operation should not result in the creation of a file. The clone operation inside btrfs needs 2 files already open (ie. it works with file descriptors, not with filenames), the empty file exists prior to the ioctl call. So the file should be removed by 'cp' (or whoever calls the clone ioctl) because they know if it makes sense to delete the file or not. david -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: BUG during log recovery
On Tue, Dec 18, 2012 at 03:10:24PM +0100, Jan Steffens wrote:
if (!caching_ctl) {
BUG_ON(!block_group_cache_done(block_group));
ret = btrfs_remove_free_space(block_group, start, num_bytes);
BUG_ON(ret); /* -ENOMEM */ // 6185
The actual value of ret is = -11 = -EAGAIN (EAX: fff5 in the report)
} else {
mutex_lock(caching_ctl-mutex);
if (start = caching_ctl-progress) {
ret = add_excluded_extent(root, start, num_bytes);
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Re: Online Deduplication for Btrfs (Master's thesis)
On Mon, Dec 17, 2012 at 2:33 PM, Alexander Block abloc...@gmail.com wrote:
I did some research on deduplication in the past and there are some
problems that you will face. I'll try to list some of them (for sure
not all).
On Mon, Dec 17, 2012 at 1:05 PM, Martin Křížek martin.kri...@gmail.com
wrote:
Hello everyone,
my name is Martin Krizek. I am a student at Faculty of Information, Brno
University of Technology, Czech Republic. As my master's thesis I chose to
work
on Online Deduplication for Btrfs.
My goal is to study Btrfs design, the offline deduplication patch [1] and to
come up with a design for the online dedup, this semester. I will be
implementing
the feature next semester (spring, that is).
The offline dedup patch is quite old and won't apply/compile anymore.
You should probably look into the clone ioctl which basically does the
same as the extent_same ioctl from the patch. Based on the clone ioctl
you can at least learn how to inject existing extents into other
inodes.
I am aware of this, thanks for pointing that out though.
I would like to shortly introduce my ideas on what I think the feature
should look
like.
* Use cases
The two main use cases for the dedup are:
1. virtual machine images
2. backup servers
* When to dedup
The choice of 'when to dedup' is not up to me as the master's thesis
specification
states online. :)
* What to dedup
I'd say the most reasonable is block-level deduplication as it seems the most
general approach to me.
Here you have two options:
1. Based on the per volume tree where you'll find btrfs_file_extent
items which point to the global extent tree.
2. Based on the global extent tree. By using the backref resolving
code, you can find which volumes refer to these extents.
Agreed.
* Controlling dedup
- turn on/off deduplication - specify subvolumes on which
deduplication is turned on
(mount, ioctl - inherited),
- turn on/off byte-by-byte comparison of blocks that have same hashes
(mount, ioctl),
- deduplication statistics (ioctl)
You'll get trouble when online dedup is turned on and off again. While
it is offline, extents still get written, but you won't have your hash
tree up-to-date. You'll need to find a way to update when dedup is
online again, without too much performance loos while updating.
Well, yes.
* Limitations
Not really limitations, but this is a list of situations when dedup will not
be triggered:
- encryption,
I've already heard somewhere else that encryption+dedup is not
possible but I don't understand why. Can someone explain this
limitation?
- compression - basically, dedup is kind of compression, might be worth to
into
it in the future though
- inline/prealloc extents,
Should be possible to dedup inline extents, but must be configurable
(e.g. minimum block size). People should also be able to completely
disable it when performance is important.
I agree that it's possible, but I don't think it's worth doing. You
won't save much storage that way.
- data across subvolumes
Should be possible. See my comment on the key in the hash tree.
Again, I agree that it's possible but this would be something I
probably won't go into.
* How to store hashes
The obvious choice would be to use the checksum tree that holds block
checksums
of each extent. The problem with the checksum tree is that the
checksums are looked up by logical address for the start of the extent data.
This is undesirable since it needs to be done the other way around. Logical
addresses need to be looked up by a hash.
To solve this, another key type would be created inside the checksum tree (or
maybe better, a new tree would be introduced) that
would have a hash as item's right-hand key value. This way, items could be
looked up on a hash:
(root, HASH_ITEM, hash)
The root value says which root (subvolume) is hashed block stored on. The
hash
value is hash itself.
With the root inside the key you make it impossible to allow
cross-subvolume deduplication. Also, the offset field in the key that
you plan to use for the hash is only 64bit, so you can at best store a
part of the hash in the key. You should probably split the hash into 3
parts: 64bit to put into the objectid field, 64bit to put into the
offset field and the remainder into the item data. A lookup would then
do the necessary splitting and in case a match is found also compare
the remainder found in the items data.
Right, I thought of this but somehow forgot to mention it. Yes, the
hash would need to be split if it does not fit into the offset. Thanks
for noticing.
The item data would be of the following structure:
struct btrfs_hash_item {
__le64 disk_bytenr;
__le64 disk_num_bytes;
__le64 offset;
}
You could omit the offset here and and store the sum of disk_bytenr
and offset in one field. You could also omit the disk_num_bytes field
if you have a fixed dedup block length. The reason: No matter what you
store here, you
Re: [GIT PULL] Btrfs updates
[ sorry, resend. My lbdb autocompleted with an extra r in kernel.org ] Hi everyone, My for-linus branch has a big set of fixes and features: Does this include raid-[56]? Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 98013356 r...@karlsbakk.net http://blogg.karlsbakk.net/ GPG Public key: http://karlsbakk.net/roysigurdkarlsbakk.pubkey.txt -- I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er et elementært imperativ for alle pedagoger å unngå eksessiv anvendelse av idiomer med xenotyp etymologi. I de fleste tilfeller eksisterer adekvate og relevante synonymer på norsk. -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [GIT PULL] Btrfs updates
On Wed, Dec 19, 2012 at 07:09:57PM +0100, Roy Sigurd Karlsbakk wrote: [ sorry, resend. My lbdb autocompleted with an extra r in kernel.org ] Hi everyone, My for-linus branch has a big set of fixes and features: Does this include raid-[56]? As Chris's last sentence in that mail says, not in this pull request, but it should be ready for Friday. Hugo. -- === Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk === PGP key: 515C238D from wwwkeys.eu.pgp.net or http://www.carfax.org.uk --- We demand rigidly defined areas of doubt and uncertainty! --- signature.asc Description: Digital signature
Re: [PATCH] Btrfs: don't bother updating the inode when evicting
On wed, 19 Dec 2012 10:02:59 -0500, Josef Bacik wrote: On Tue, Dec 18, 2012 at 06:58:33PM -0700, Miao Xie wrote: On tue, 18 Dec 2012 15:51:57 -0500, Josef Bacik wrote: We're deleting the stupid thing, no sense in updating the inode for the new size. We're running into having 50-100 orphans left over with xfstests 83 because of ENOSPC when trying to start the transaction for the inode update. This patch fixes this problem. Thanks, This patch is wrong, it will introduce the inconsonant metadata in the snapshot tree. The reason is folloing: commit 8407aa464331556e4f6784f974030b83fc7585ed Author: Miao Xie mi...@cn.fujitsu.com Date: Fri Sep 7 01:43:32 2012 -0600 Btrfs: fix corrupted metadata in the snapshot When we delete a inode, we will remove all the delayed items including delayed inode update, and then truncate all the relative metadata. If there is lots of metadata, we will end the current transaction, and start a new transaction to truncate the left metadata. In this way, we will leave a inode item that its link counter is 0, and also may leave some directory index items in fs/file tree after the current transaction ends. In other words, the metadata in this fs/file tree is inconsistent. If we create a snapshot for this tree now, we will find a inode with corrupted metadata in the new snapshot, and we won't continue to drop the left metadata, because its link counter is not 0. We fix this problem by updating the inode item before the current transaction ends. Signed-off-by: Miao Xie mi...@cn.fujitsu.com So why don't we fix unlink to call btrfs_update_inode_item so that the nlink counter is set to 0? The orphan item will be carried over into the snapshot if we don't actually evict the inode before we do the snapshot and then the orphan cleanup will take care of the rest? Thanks, But it would make the file deletion performance down. Thanks Miao Josef -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: About btrfs qgroup import/export command
On Wed, 19 Dec 2012 12:40:25 +0100, Arne Jansen wrote: On 19.12.2012 12:25, Miao Xie wrote: Hi, everyone. As we know, there is no backup function for qgroup. when the problem occurs, the users must recover qgroup configuration manually, it is not convenient. And besides that, some users might want to import an existed qgroup configuration into a new filesystem. Btrfs does not have such a function,it can only be done manually. So we want to implement btrfs qgroup import/export commands. 1)'btrfs qgroup export' commands will export qgroup tree into a user's specified file.(stdout by default) 2)user may modify the configuration file firstly and then import it into the filesystem.(by 'btrfs qgroup import' command) The file may be formated as the following: Qgroupid is_compressed is_exclusive limited_sizeparent -- 0/10 0 10G1/0 1/01 1 20G--- If 'is_exclusive' is set, 'limited_size' corresponds to max exlusive size, else max referenced size. Here 'parent' exclude ancestral qgroups. Is there any comment about this idea? The configuration only really makes sense in combination with the existing subvolumes. Even if the target has subvolumes under the same name, they might have different internal IDs. So it might make more sense to address the level 0 qgroups by name. Yeah. Thanks for your suggest. Also it might be misleading to apply a configuration to an existing fs, as it currently is not possible get a correct accounting if the fs is not empty. Rescan is not yet implemented. So instead of just saving and restoring the qgroup config, it might make more sense to create a new filesystem including all subvolumes and quota config from a config file. But, I'm not completely convinced that this is a features that is needed frequently. If I want a standard deployment, I simple write a script that creates the fs + subvol + quota. But if you set a new value for some groups, you must modify your script at the same time, it is a bit troublesome. Thanks Miao -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
btrfs warning in 3.7.0 with nfsd
I'm getting some kernel warnings from a btrfs raid1 filesystem that's serving up nfs4 to a couple of other computers on a small home network. I ran 3.6.x for several weeks before upgrading and didn't see any warnings like this. [ 1712.223791] WARNING: at fs/btrfs/tree-log.c:3716 btrfs_log_inode_parent+0x291/0x2fd [btrfs]() [ 1712.223793] Hardware name: System Product Name [ 1712.223794] Modules linked in: lirc_dev xt_tcpudp iptable_filter ip_tables x_tables nfsd auth_rpcgss nfs_acl nfs lockd fscache sunrpc loop firewire_sbp2 snd_hda_codec_analog iTCO_wdt iTCO_vendor_support snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq coretemp kvm_intel acpi_cpufreq mperf snd_timer lpc_ich evdev asus_atk0110 kvm processor button psmouse serio_raw snd_seq_device mfd_core parport_pc pcspkr thermal_sys i2c_i801 snd microcode soundcore parport i2c_core btrfs crc32c libcrc32c zlib_deflate sg sd_mod crc_t10dif ata_generic uhci_hcd pata_jmicron ahci libahci firewire_ohci firewire_core crc_itu_t ata_piix libata r8169 mii scsi_mod ehci_hcd usbcore usb_common [ 1712.223840] Pid: 2314, comm: nfsd Not tainted 3.7.0 #1 [ 1712.223842] Call Trace: [ 1712.223849] [8103cd4c] ? warn_slowpath_common+0x76/0x8a [ 1712.223864] [a01bd099] ? btrfs_log_inode_parent+0x291/0x2fd [btrfs] [ 1712.223879] [a01bd13a] ? btrfs_log_dentry_safe+0x35/0x4e [btrfs] [ 1712.223894] [a019e298] ? btrfs_sync_file+0x151/0x1e6 [btrfs] [ 1712.223908] [a019f59f] ? btrfs_file_aio_write+0x374/0x3c5 [btrfs] [ 1712.223913] [812e9dbe] ? tcp_release_cb+0x46/0x94 [ 1712.223917] [8129f2b2] ? release_sock+0xe9/0x11f [ 1712.223922] [812dee9c] ? tcp_sendmsg+0x6ef/0x801 [ 1712.223936] [a019f22b] ? __btrfs_buffered_write+0x2e8/0x2e8 [btrfs] [ 1712.223940] [81102b8a] ? do_sync_readv_writev+0x57/0x94 [ 1712.223943] [81102dd3] ? do_readv_writev+0x94/0x108 [ 1712.223947] [8115b945] ? exportfs_decode_fh+0xcc/0x257 [ 1712.223958] [a034ba0b] ? seconds_since_boot+0x11/0x1a [sunrpc] [ 1712.223966] [a034c94a] ? cache_check+0x2c/0x24c [sunrpc] [ 1712.223975] [a03ad246] ? nfsd_vfs_write.isra.8+0xc3/0x20e [nfsd] [ 1712.223978] [810fa789] ? kmem_cache_alloc+0x8e/0xfd [ 1712.223987] [a03bd2bd] ? renew_client_locked+0x76/0x7f [nfsd] [ 1712.223995] [a03bd2de] ? renew_client+0x18/0x25 [nfsd] [ 1712.224003] [a03bd332] ? find_confirmed_client+0x47/0x5c [nfsd] [ 1712.224024] [a03ae9ed] ? nfsd_write+0x7f/0xf0 [nfsd] [ 1712.224033] [81060f4b] ? should_resched+0x5/0x23 [ 1712.224040] [a03b68fb] ? nfsd4_write+0xcb/0xf3 [nfsd] [ 1712.224049] [a03b64b8] ? nfsd4_proc_compound+0x224/0x3b2 [nfsd] [ 1712.224057] [a03aa7b2] ? nfsd_dispatch+0x93/0x145 [nfsd] [ 1712.224069] [a034539f] ? svc_process_common+0x289/0x439 [sunrpc] [ 1712.224075] [a03aa076] ? nfsd_destroy.constprop.2+0x3c/0x3c [nfsd] [ 1712.224086] [a0345f26] ? svc_process+0x111/0x12d [sunrpc] [ 1712.224095] [a03aa120] ? nfsd+0xaa/0xfe [nfsd] [ 1712.224100] [81056d60] ? kthread+0x81/0x89 [ 1712.224105] [81056cdf] ? __kthread_parkme+0x5c/0x5c [ 1712.224109] [813734fc] ? ret_from_fork+0x7c/0xb0 [ 1712.224114] [81056cdf] ? __kthread_parkme+0x5c/0x5c [ 1712.224116] ---[ end trace 58e10839083ba9da ]--- This is the first warning; subsequent ones look broadly similar to my eyes. btrfs fi show: Label: none uuid: 9d4db9e3-b9c3-4f6d-8cb4-60ff55e96d82 Total devices 3 FS bytes used 1.02TB devid3 size 1.36TB used 1.22TB path /dev/sdb1 devid1 size 1.36TB used 1.18TB path /dev/sdc1 devid2 size 464.73GB used 318.03GB path /dev/sda1 This is a vanilla amd64 3.7.0 built using Debian's make-kpkg. Userspace is a recent Debian testing. I'm not sure exactly what triggers this but it seems to happen regularly with NFS activity. I haven't observed any failures or bad performance from this. I know 3.7 introduced some NFS changes too so I hope I'm directing this report correctly. Should I be concerned about my data? Can I provide any other information? I can try btrfs-next too if it'll help. Thanks! Steve -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
