Commit Graph

25873 Commits

Author SHA1 Message Date
Jan Schmidt
926dd8a640 Btrfs: add missing spin_lock for insertion into tree mod log
tree_mod_alloc calls __get_tree_mod_seq and must acquire a spinlock before
doing so.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-31 19:56:18 +02:00
Jan Schmidt
3301958b7c Btrfs: add inodes before dropping the extent lock in find_all_leafs
We must build up the inode list with the extent lock held after following
indirect refs.

This also requires an extension to ulists, which allows to modify the stored
aux value in case a key already exists in the list.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-31 19:53:08 +02:00
Jan Schmidt
95a06077f7 Btrfs: use delayed ref sequence numbers for all fs-tree updates
The sequence number for delayed refs is needed to postpone certain delayed
refs for a very short period while walking backrefs. Before the tree
modification log, we thought we'd only have to hold back those references
that don't have a counter operation.

While now we've the tree mod log, we're rewinding fs tree blocks to a
defined consistent state. We cannot know in advance for which tree block
we'll be doing rewind operations later. Therefore, we must postpone all the
delayed refs for fs-tree blocks, even those having a counter operation.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 18:18:21 +02:00
Jan Schmidt
20b297d620 Btrfs: tree mod log sanity checks in join_transaction
When a fresh transaction begins, the tree mod log must be clean. Users of
the tree modification log must ensure they never span across transaction
boundaries.

We reset the sequence to 0 in this safe situation to make absolutely sure
overflow can't happen.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:36 +02:00
Jan Schmidt
19ae4e8133 Btrfs: fs_info variable for join_transaction
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:35 +02:00
Jan Schmidt
8445f61cad Btrfs: use the tree modification log for backref resolving
This enables backref resolving on life trees while they are changing. This
is a prerequisite for quota groups and just nice to have for everything
else.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:34 +02:00
Jan Schmidt
5d9e75c41d Btrfs: add btrfs_search_old_slot
The tree modification log together with the current state of the tree gives
a consistent, old version of the tree. btrfs_search_old_slot is used to
search through this old version and return old (dummy!) extent buffers.
Naturally, this function cannot do any tree modifications.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:33 +02:00
Jan Schmidt
f3ea38da3e Btrfs: add del_ptr and insert_ptr modifications to the tree mod log
Record all relevant modifications to block pointers in the tree mod log so
that we can rewind them later on for backref walking.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:32 +02:00
Jan Schmidt
f230475e62 Btrfs: put all block modifications into the tree mod log
When running functions that can make changes to the internal trees
(e.g. btrfs_search_slot), we check if somebody may be interested in the
block we're currently modifying. If so, we record our modification to be
able to rewind it later on.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:29 +02:00
Jan Schmidt
bd989ba359 Btrfs: add tree modification log functions
The tree mod log will log modifications made fs-tree nodes. Most
modifications are done by autobalance of the tree. Such changes are recorded
as long as a block entry exists. When released, the log is cleaned.

With the tree modification log, it's possible to reconstruct a consistent
old state of the tree. This is required to do backref walking on a busy
file system.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:01 +02:00
Jan Schmidt
f29021b29a Btrfs: add tree mod log to fs_info
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:54 +02:00
Jan Schmidt
815a51c74a Btrfs: dummy extent buffers for tree mod log
The tree modification log needs two ways to create dummy extent buffers,
once by allocating a fresh one (to rebuild an old root) and once by
cloning an existing one (to make private rewind modifications) to it.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:54 +02:00
Jan Schmidt
64947ec0d1 Btrfs: move struct seq_list to ctree.h
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:53 +02:00
Jan Schmidt
5581a51a59 Btrfs: don't set for_cow parameter for tree block functions
Three callers of btrfs_free_tree_block or btrfs_alloc_tree_block passed
parameter for_cow = 1. In fact, these two functions should never mark
their tree modification operations as for_cow, because they can change
the number of blocks referenced by a tree.

Hence, we remove the extra for_cow parameter from these functions and
make them pass a zero down.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:53 +02:00
Jan Schmidt
976b1908d9 Btrfs: look into the extent during find_all_leafs
Before this patch we called find_all_leafs for a data extent, then called
find_all_roots and then looked into the extent to grab the information
we were seeking. This was done without holding the leaves locked to avoid
deadlocks. However, this can obviouly race with concurrent tree
modifications.

Instead, we now look into the extent while we're holding the lock during
find_all_leafs and store this information together with the leaf list.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:52 +02:00
Jan Schmidt
d5c88b735f Btrfs: bugfix: ignore the wrong key for indirect tree block backrefs
The key we store with a tree block backref is only a hint. It is set when
the ref is created and can remain correct for a long time. As the tree is
rebalanced, however, eventually the key no longer points to the correct
destination.

With this patch, we change find_parent_nodes to no longer add keys unless it
knows for sure they're correct (e.g. because they're for an extent data
backref). Then when we later encounter a backref ref with no parent and no
key set, we grab the block and take the first key from the block itself.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:51 +02:00
Jan Schmidt
dadcaf78b5 Btrfs: bugfix in btrfs_find_parent_nodes
That one has been around since the addition of backref.c. Due to the way we
calculate our slot numbers, after adding inline refs we're missing one keyed
ref unless it's located at the beginning of a new leaf.

Reported-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:51 +02:00
Jan Schmidt
cd1b413c5c Btrfs: ulist realloc bugfix
ulist_next gets the pointer to the previously returned element to find the
next element from there. However, when we call ulist_add while iteration
with ulist_next is in progress (ulist explicitly supports this), we can
realloc the ulist internal memory, which makes the pointer to the previous
element useless.

Instead, we now use an iterator parameter that's independent from the
internal pointers.

Reported-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:49 +02:00
Chris Mason
b9fab919b7 Btrfs: avoid sleeping in verify_parent_transid while atomic
verify_parent_transid needs to lock the extent range to make
sure no IO is underway, and so it can safely clear the
uptodate bits if our checks fail.

But, a few callers are using it with spinlocks held.  Most
of the time, the generation numbers are going to match, and
we don't want to switch to a blocking lock just for the error
case.  This adds an atomic flag to verify_parent_transid,
and changes it to return EAGAIN if it needs to block to
properly verifiy things.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-06 07:23:47 -04:00
Stefan Behrens
ea9947b439 Btrfs: fix crash in scrub repair code when device is missing
Fix that when scrub tries to repair an I/O or checksum error and one of
the devices containing the mirror is missing, it crashes in bio_add_page
because the bdev is a NULL pointer for missing devices.

Reported-by: Marco L. Crociani <marco.crociani@gmail.com>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:07 -04:00
Alexander Block
d04b1debc9 btrfs: Fix mismatching struct members in ioctl.h
Fix the size members of btrfs_ioctl_ino_path_args and
btrfs_ioctl_logical_ino_args. The user space btrfs-progs utilities used
__u64 and the kernel headers used __u32 before.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:06 -04:00
Josef Bacik
17de39ac17 Btrfs: fix page leak when allocing extent buffers
If we happen to alloc a extent buffer and then alloc a page and notice that
page is already attached to an extent buffer, we will only unlock it and
free our existing eb.  Any pages currently attached to that eb will be
properly freed, but we don't do the page_cache_release() on the page where
we noticed the other extent buffer which can cause us to leak pages and I
hope cause the weird issues we've been seeing in this area.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:16:06 -04:00
Chris Mason
e5846fc665 Btrfs: Add properly locking around add_root_to_dirty_list
add_root_to_dirty_list happens once at the very beginning of the
transaction, but it is still racey.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04 15:14:11 -04:00
Chris Mason
dc7fdde39e Btrfs: reduce lock contention during extent insertion
We're spending huge amounts of time on lock contention during
end_io processing because we unconditionally assume we are overwriting
an existing extent in the file for each IO.

This checks to see if we are outside i_size, and if so, it uses a
less expensive readonly search of the btree to look for existing
extents.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 14:51:05 -04:00
Chris Mason
fede766f28 Btrfs: avoid deadlocks from GFP_KERNEL allocations during btrfs_real_readdir
Btrfs has an optimization where it will preallocate dentries during
readdir to fill in enough information to open the inode without an extra
lookup.

But, we're calling d_alloc, which is doing GFP_KERNEL allocations, and
that leads to deadlocks because our readdir code has tree locks held.

For now, disable this optimization.  We'll fix the gfp mask in the next
merge window.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 14:23:22 -04:00
Daniel J Blueman
7654b72417 Btrfs: Fix space checking during fs resize
Fix out-of-space checking, addressing a warning and potential resource
leak when resizing the filesystem down while allocating blocks.

Signed-off-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 13:55:14 -04:00
Stefan Behrens
1f699d38b6 Btrfs: fix block_rsv and space_info lock ordering
may_commit_transaction() calls
        spin_lock(&space_info->lock);
        spin_lock(&delayed_rsv->lock);
and update_global_block_rsv() calls
        spin_lock(&block_rsv->lock);
        spin_lock(&sinfo->lock);

Lockdep complains about this at run time.
Everywhere except in update_global_block_rsv(), the space_info lock is
the outer lock, therefore the locking order in update_global_block_rsv()
is changed.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 13:55:14 -04:00
Daniel J Blueman
1daf3540fa Btrfs: Prevent root_list corruption
I was seeing root_list corruption on unmount during fs resize in 3.4-rc4; add
correct locking to address this.

Signed-off-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 13:55:13 -04:00
Jan Schmidt
3e74317ad7 Btrfs: fix repair code for RAID10
btrfs_map_block sets mirror_num, so that the repair code knows eventually
which device gave us the read error. For RAID10, mirror_num must be 1 or 2.
Before this fix mirror_num was incorrectly related to our stripe index.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 13:55:13 -04:00
Josef Bacik
996d282c7f Btrfs: do not start delalloc inodes during sync
btrfs_start_delalloc_inodes will just walk the list of delalloc inodes and
start writing them out, but it doesn't splice the list or anything so as
long as somebody is doing work on the box you could end up in this section
_forever_.  So just remove it, it's not needed anyway since sync will start
writeback on all inodes anyway, all we need to do is wait for ordered
extents and then we can commit the transaction.  In my horrible torture test
sync goes from taking 4 minutes to about 1.5 minutes.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27 13:55:12 -04:00
Stefan Behrens
25cd999e1a Btrfs: fix that check_int_data mount option was ignored
The bitfield member mount_opt was too small by one bit to hold the mount
option that enabled to include data extents in the integrity checker.
Since the same issue happened when the BTRFS_MOUNT_PANIC_ON_FATAL_ERROR
option was added (git rebase silently merges so that the increase of the
size of the bitfield member is lost), the bit limit was removed entirely.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18 19:22:38 +02:00
Stefan Behrens
5c84fc3c39 Btrfs: don't count CRC or header errors twice while scrubbing
Each CRC or header error was counted twice, this is now fixed.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18 19:22:36 +02:00
Stefan Behrens
99ba55ad69 Btrfs: fix btrfs_ioctl_dev_info() crash on missing device
When a filesystem is mounted with the degraded option, it is
possible that some of the devices are not there.
btrfs_ioctl_dev_info() crashs in this case because the device
name is a NULL pointer. This ioctl was only used for scrub.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18 19:22:35 +02:00
Arne Jansen
b9688bb845 btrfs: don't return EINTR
It is basically a good thing if we are interruptible when waiting for
free space, but the generality in which it is implemented currently
leads to system calls being interruptible that are not documented this
way. For example git can't handle interrupted unlink(), leading to
corrupt repos under space pressure.
Instead we raise the bar to only be interruptible by SIGKILL.
Thanks to David Sterba for suggesting this.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-04-18 19:22:33 +02:00
Dan Carpenter
253beebd5a Btrfs: double unlock bug in error handling
The caller expects this function to return with the lock held and
releases it immediately on error.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2012-04-18 19:22:31 +02:00
Josef Bacik
5cf1ab5613 Btrfs: always store the mirror we read the eb from
A user reported a panic where we were trying to fix a bad mirror but the
mirror number we were giving was 0, which is invalid.  This is because we
don't do the transid verification until after the read, so as far as the
read code is concerned the read was a success.  So instead store the mirror
we read from so that if there is some failure post read we know which mirror
to try next and which mirror needs to be fixed if we find a good copy of the
block.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-04-18 19:22:30 +02:00
Julia Lawall
48d282326b fs/btrfs/volumes.c: add missing free_fs_devices
Free fs_devices as done in the error-handling code just below.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
2012-04-18 19:22:28 +02:00
Sergei Trofimovich
8a3db1849e btrfs: fix early abort in 'remount'
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Josef Bacik <josef@redhat.com>
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
2012-04-18 19:22:26 +02:00
Ilya Dryomov
37db63a400 Btrfs: fix max chunk size check in chunk allocator
Fix a bug, where in case we need to adjust stripe_size so that the
length of the resulting chunk is less than or equal to max_chunk_size,
DUP chunks turn out to be only half as big as they could be.

Cc: Arne Jansen <sensille@gmx.net>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-04-18 19:22:25 +02:00
Jan Schmidt
b916a59adf Btrfs: add missing read locks in backref.c
iref_to_path and iterate_irefs both increment the eb's refcount to use it
after releasing the path. Both depend on consistent data remaining in the
extent buffer and need a read lock to protect it.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-04-18 19:22:23 +02:00
Jan Schmidt
aefc1eb13e Btrfs: don't call free_extent_buffer twice in iterate_irefs
Avoid calling free_extent_buffer more than once when the iterator function
returns non-zero. The only code that uses this is scrub repair for corrupted
nodatasum blocks.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-04-18 19:22:21 +02:00
Jesper Juhl
4735fb2828 Btrfs: Make free_ipath() deal gracefully with NULL pointers
Make free_ipath() behave like most other freeing functions in the
kernel and gracefully do nothing when passed a NULL pointer.

Besides this making the bahaviour consistent with functions such as
kfree(), vfree(), btrfs_free_path() etc etc, it also fixes a real NULL
deref issue in fs/btrfs/ioctl.c::btrfs_ioctl_ino_to_path(). In that
function we have this code:

...
        ipath = init_ipath(size, root, path);
        if (IS_ERR(ipath)) {
                ret = PTR_ERR(ipath);
                ipath = NULL;
                goto out;
        }
...
out:
        btrfs_free_path(path);
        free_ipath(ipath);
...

If we ever take the true branch of that 'if' statement we'll end up
passing a NULL pointer to free_ipath() which will subsequently
dereference it and we'll go "Boom" :-(
This patch will avoid that.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
2012-04-18 19:22:20 +02:00
Li Zefan
cdc6a39525 Btrfs: avoid possible use-after-free in clear_extent_bit()
clear_extent_bit()
{
    next_node = rb_next(&state->rb_node);
    ...
    clear_state_bit(state);  <-- this may free next_node
    if (next_node) {
        state = rb_entry(next_node);
        ...
    }
}

clear_state_bit() calls merge_state() which may free the next node
of the passing extent_state, so clear_extent_bit() may end up
referencing freed memory.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-18 19:22:18 +02:00
Li Zefan
8e52acf704 Btrfs: retrurn void from clear_state_bit
Currently it returns a set of bits that were cleared, but this return
value is not used at all.

Moreover it doesn't seem to be useful, because we may clear the bits
of a few extent_states, but only the cleared bits of last one is
returned.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-18 19:22:16 +02:00
David Sterba
871383be59 btrfs: add missing unlocks to transaction abort paths
Added in commit 49b25e0540
("btrfs: enhance transaction abort infrastructure")

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2012-04-18 19:22:14 +02:00
Liu Bo
8d082fb727 Btrfs: do not mount when we have a sectorsize unequal to PAGE_SIZE
Our code is not ready to cope with a sectorsize that's not equal to PAGE_SIZE.
It will lead to hanging-on while writing something.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
2012-04-18 19:22:13 +02:00
Arne Jansen
207a232cca btrfs: don't add both copies of DUP to reada extent tree
Normally when there are 2 copies of a block, we add both to the
reada extent tree and prefetch only the one that is easier to reach.
This way we can better utilize multiple devices.
In case of DUP this makes no sense as both copies reside on the
same device.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-04-18 19:12:44 +02:00
Arne Jansen
8c9c2bf7a3 btrfs: fix race in reada
When inserting into the radix tree returns EEXIST, get the existing
entry without giving up the spinlock in between.
There was a race for both the zones trees and the extent tree.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-04-18 19:12:44 +02:00
Li Zefan
848cce0d41 Btrfs: avoid setting ->d_op twice
Follow those instructions, and you'll trigger a warning in the
beginning of d_set_d_op():

  # mkfs.btrfs /dev/loop3
  # mount /dev/loop3 /mnt
  # btrfs sub create /mnt/sub
  # btrfs sub snap /mnt /mnt/snap
  # touch /mnt/snap/sub
  touch: cannot touch `tmp': Permission denied

__d_alloc() set d_op to sb->s_d_op (btrfs_dentry_operations), and
then simple_lookup() reset it to simple_dentry_operations, which
triggered the warning.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-18 19:12:44 +02:00
Josef Bacik
d53ba47484 Btrfs: use commit root when loading free space cache
A user reported that booting his box up with btrfs root on 3.4 was way
slower than on 3.3 because I removed the ideal caching code.  It turns out
that we don't load the free space cache if we're in a commit for deadlock
reasons, but since we're reading the cache and it hasn't changed yet we are
safe reading the inode and free space item from the commit root, so do that
and remove all of the deadlock checks so we don't unnecessarily skip loading
the free space cache.  The user reported this fixed the slowness.  Thanks,

Tested-by: Calvin Walton <calvin.walton@kepstin.ca>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-12 20:54:01 -04:00