While running btrfs/004 from xfstests, after 503 iterations, dmesg reported
a deadlock between tasks iterating inode refs and tasks running delayed inodes
(during a transaction commit).
It turns out that iterating inode refs implies doing one tree search and
release all nodes in the path except the leaf node, and then passing that
leaf node to btrfs_ref_to_path(), which in turn does another tree search
without releasing the lock on the leaf node it received as parameter.
This is a problem when other task wants to write to the btree as well and
ends up updating the leaf that is read locked - the writer task locks the
parent of the leaf and then blocks waiting for the leaf's lock to be
released - at the same time, the task executing btrfs_ref_to_path()
does a second tree search, without releasing the lock on the first leaf,
and wants to access a leaf (the same or another one) that is a child of
the same parent, resulting in a deadlock.
The trace reported by lockdep follows.
[84314.936373] INFO: task fsstress:11930 blocked for more than 120 seconds.
[84314.936381] Tainted: G W O 3.12.0-fdm-btrfs-next-16+ #70
[84314.936383] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[84314.936386] fsstress D ffff8806e1bf8000 0 11930 11926 0x00000000
[84314.936393] ffff8804d6d89b78 0000000000000046 ffff8804d6d89b18 ffffffff810bd8bd
[84314.936399] ffff8806e1bf8000 ffff8804d6d89fd8 ffff8804d6d89fd8 ffff8804d6d89fd8
[84314.936405] ffff880806308000 ffff8806e1bf8000 ffff8804d6d89c08 ffff8804deb8f190
[84314.936410] Call Trace:
[84314.936421] [<ffffffff810bd8bd>] ? trace_hardirqs_on+0xd/0x10
[84314.936428] [<ffffffff81774269>] schedule+0x29/0x70
[84314.936451] [<ffffffffa0715bf5>] btrfs_tree_lock+0x75/0x270 [btrfs]
[84314.936457] [<ffffffff810715c0>] ? __init_waitqueue_head+0x60/0x60
[84314.936470] [<ffffffffa06ba231>] btrfs_search_slot+0x7f1/0x930 [btrfs]
[84314.936489] [<ffffffffa0731c2a>] ? __btrfs_run_delayed_items+0x13a/0x1e0 [btrfs]
[84314.936504] [<ffffffffa06d2e1f>] btrfs_lookup_inode+0x2f/0xa0 [btrfs]
[84314.936510] [<ffffffff810bd6ef>] ? trace_hardirqs_on_caller+0x1f/0x1e0
[84314.936528] [<ffffffffa073173c>] __btrfs_update_delayed_inode+0x4c/0x1d0 [btrfs]
[84314.936543] [<ffffffffa0731c2a>] ? __btrfs_run_delayed_items+0x13a/0x1e0 [btrfs]
[84314.936558] [<ffffffffa0731c2a>] ? __btrfs_run_delayed_items+0x13a/0x1e0 [btrfs]
[84314.936573] [<ffffffffa0731c82>] __btrfs_run_delayed_items+0x192/0x1e0 [btrfs]
[84314.936589] [<ffffffffa0731d03>] btrfs_run_delayed_items+0x13/0x20 [btrfs]
[84314.936604] [<ffffffffa06dbcd4>] btrfs_flush_all_pending_stuffs+0x24/0x80 [btrfs]
[84314.936620] [<ffffffffa06ddc13>] btrfs_commit_transaction+0x223/0xa20 [btrfs]
[84314.936630] [<ffffffffa06ae5ae>] btrfs_sync_fs+0x6e/0x110 [btrfs]
[84314.936635] [<ffffffff811d0b50>] ? __sync_filesystem+0x60/0x60
[84314.936639] [<ffffffff811d0b50>] ? __sync_filesystem+0x60/0x60
[84314.936643] [<ffffffff811d0b70>] sync_fs_one_sb+0x20/0x30
[84314.936648] [<ffffffff811a3541>] iterate_supers+0xf1/0x100
[84314.936652] [<ffffffff811d0c45>] sys_sync+0x55/0x90
[84314.936658] [<ffffffff8177ef12>] system_call_fastpath+0x16/0x1b
[84314.936660] INFO: lockdep is turned off.
[84314.936663] INFO: task btrfs:11955 blocked for more than 120 seconds.
[84314.936666] Tainted: G W O 3.12.0-fdm-btrfs-next-16+ #70
[84314.936668] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[84314.936670] btrfs D ffff880541729a88 0 11955 11608 0x00000000
[84314.936674] ffff880541729a38 0000000000000046 ffff8805417299d8 ffffffff810bd8bd
[84314.936680] ffff88075430c8a0 ffff880541729fd8 ffff880541729fd8 ffff880541729fd8
[84314.936685] ffffffff81c104e0 ffff88075430c8a0 ffff8804de8b00b8 ffff8804de8b0000
[84314.936690] Call Trace:
[84314.936695] [<ffffffff810bd8bd>] ? trace_hardirqs_on+0xd/0x10
[84314.936700] [<ffffffff81774269>] schedule+0x29/0x70
[84314.936717] [<ffffffffa0715815>] btrfs_tree_read_lock+0xd5/0x140 [btrfs]
[84314.936721] [<ffffffff810715c0>] ? __init_waitqueue_head+0x60/0x60
[84314.936733] [<ffffffffa06ba201>] btrfs_search_slot+0x7c1/0x930 [btrfs]
[84314.936746] [<ffffffffa06bd505>] btrfs_find_item+0x55/0x160 [btrfs]
[84314.936763] [<ffffffffa06ff689>] ? free_extent_buffer+0x49/0xc0 [btrfs]
[84314.936780] [<ffffffffa073c9ca>] btrfs_ref_to_path+0xba/0x1e0 [btrfs]
[84314.936797] [<ffffffffa06f9719>] ? release_extent_buffer+0xb9/0xe0 [btrfs]
[84314.936813] [<ffffffffa06ff689>] ? free_extent_buffer+0x49/0xc0 [btrfs]
[84314.936830] [<ffffffffa073cb50>] inode_to_path+0x60/0xd0 [btrfs]
[84314.936846] [<ffffffffa073d365>] paths_from_inode+0x115/0x3c0 [btrfs]
[84314.936851] [<ffffffff8118dd44>] ? kmem_cache_alloc_trace+0x114/0x200
[84314.936868] [<ffffffffa0714494>] btrfs_ioctl+0xf14/0x2030 [btrfs]
[84314.936873] [<ffffffff817762db>] ? _raw_spin_unlock+0x2b/0x50
[84314.936877] [<ffffffff8116598f>] ? handle_mm_fault+0x34f/0xb00
[84314.936882] [<ffffffff81075563>] ? up_read+0x23/0x40
[84314.936886] [<ffffffff8177a41c>] ? __do_page_fault+0x20c/0x5a0
[84314.936892] [<ffffffff811b2946>] do_vfs_ioctl+0x96/0x570
[84314.936896] [<ffffffff81776e23>] ? error_sti+0x5/0x6
[84314.936901] [<ffffffff810b71e8>] ? trace_hardirqs_off_caller+0x28/0xd0
[84314.936906] [<ffffffff81776a09>] ? retint_swapgs+0xe/0x13
[84314.936910] [<ffffffff811b2eb1>] SyS_ioctl+0x91/0xb0
[84314.936915] [<ffffffff813eecde>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[84314.936920] [<ffffffff8177ef12>] system_call_fastpath+0x16/0x1b
[84314.936922] INFO: lockdep is turned off.
[84434.866873] INFO: task btrfs-transacti:11921 blocked for more than 120 seconds.
[84434.866881] Tainted: G W O 3.12.0-fdm-btrfs-next-16+ #70
[84434.866883] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[84434.866886] btrfs-transacti D ffff880755b6a478 0 11921 2 0x00000000
[84434.866893] ffff8800735b9ce8 0000000000000046 ffff8800735b9c88 ffffffff810bd8bd
[84434.866899] ffff8805a1b848a0 ffff8800735b9fd8 ffff8800735b9fd8 ffff8800735b9fd8
[84434.866904] ffffffff81c104e0 ffff8805a1b848a0 ffff880755b6a478 ffff8804cece78f0
[84434.866910] Call Trace:
[84434.866920] [<ffffffff810bd8bd>] ? trace_hardirqs_on+0xd/0x10
[84434.866927] [<ffffffff81774269>] schedule+0x29/0x70
[84434.866948] [<ffffffffa06dd2ef>] wait_current_trans.isra.33+0xbf/0x120 [btrfs]
[84434.866954] [<ffffffff810715c0>] ? __init_waitqueue_head+0x60/0x60
[84434.866970] [<ffffffffa06dec18>] start_transaction+0x388/0x5a0 [btrfs]
[84434.866985] [<ffffffffa06db9b5>] ? transaction_kthread+0xb5/0x280 [btrfs]
[84434.866999] [<ffffffffa06dee97>] btrfs_attach_transaction+0x17/0x20 [btrfs]
[84434.867012] [<ffffffffa06dba9e>] transaction_kthread+0x19e/0x280 [btrfs]
[84434.867026] [<ffffffffa06db900>] ? open_ctree+0x2260/0x2260 [btrfs]
[84434.867030] [<ffffffff81070dad>] kthread+0xed/0x100
[84434.867035] [<ffffffff81070cc0>] ? flush_kthread_worker+0x190/0x190
[84434.867040] [<ffffffff8177ee6c>] ret_from_fork+0x7c/0xb0
[84434.867044] [<ffffffff81070cc0>] ? flush_kthread_worker+0x190/0x190
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
There are many btrfs functions that manually search the tree for an
item. They all reimplement the same mechanism and differ in the
conditions that they use to find the item. __inode_info() is one such
example. Zach Brown proposed creating a new interface to take the place
of these functions.
This patch is the first step to creating the interface. A new function,
btrfs_find_item, has been added to ctree.c and prototyped in ctree.h.
It is identical to __inode_info, except that the order of the parameters
has been rearranged to more closely those of similar functions elsewhere
in the code (now, root and path come first, then the objectid, offset
and type, and the key to be filled in last). __inode_info's callers have
been set to call this new function instead, and __inode_info itself has
been removed.
Signed-off-by: Kelley Nielsen <kelleynnn@gmail.com>
Suggested-by: Zach Brown <zab@redhat.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
Use WARN_ON()'s return value in place of WARN_ON(1) for cleaner source
code that outputs a more descriptive warnings. Also fix the styling
warning of redundant braces that came up as a result of this fix.
Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Running balance and defrag concurrently can end up with a crash:
kernel BUG at fs/btrfs/relocation.c:4528!
RIP: 0010:[<ffffffffa01ac33b>] [<ffffffffa01ac33b>] btrfs_reloc_cow_block+ 0x1eb/0x230 [btrfs]
Call Trace:
[<ffffffffa01398c1>] ? update_ref_for_cow+0x241/0x380 [btrfs]
[<ffffffffa0180bad>] ? copy_extent_buffer+0xad/0x110 [btrfs]
[<ffffffffa0139da1>] __btrfs_cow_block+0x3a1/0x520 [btrfs]
[<ffffffffa013a0b6>] btrfs_cow_block+0x116/0x1b0 [btrfs]
[<ffffffffa013ddad>] btrfs_search_slot+0x43d/0x970 [btrfs]
[<ffffffffa0153c57>] btrfs_lookup_file_extent+0x37/0x40 [btrfs]
[<ffffffffa0172a5e>] __btrfs_drop_extents+0x11e/0xae0 [btrfs]
[<ffffffffa013b3fd>] ? generic_bin_search.constprop.39+0x8d/0x1a0 [btrfs]
[<ffffffff8117d14a>] ? kmem_cache_alloc+0x1da/0x200
[<ffffffffa0138e7a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs]
[<ffffffffa0173ef0>] btrfs_drop_extents+0x60/0x90 [btrfs]
[<ffffffffa016b24d>] relink_extent_backref+0x2ed/0x780 [btrfs]
[<ffffffffa0162fe0>] ? btrfs_submit_bio_hook+0x1e0/0x1e0 [btrfs]
[<ffffffffa01b8ed7>] ? iterate_inodes_from_logical+0x87/0xa0 [btrfs]
[<ffffffffa016b909>] btrfs_finish_ordered_io+0x229/0xac0 [btrfs]
[<ffffffffa016c3b5>] finish_ordered_fn+0x15/0x20 [btrfs]
[<ffffffffa018cbe5>] worker_loop+0x125/0x4e0 [btrfs]
[<ffffffffa018cac0>] ? btrfs_queue_worker+0x300/0x300 [btrfs]
[<ffffffff81075ea0>] kthread+0xc0/0xd0
[<ffffffff81075de0>] ? insert_kthread_work+0x40/0x40
[<ffffffff8164796c>] ret_from_fork+0x7c/0xb0
[<ffffffff81075de0>] ? insert_kthread_work+0x40/0x40
----------------------------------------------------------------------
It turns out to be that balance operation will bump root's @last_snapshot,
which enables snapshot-aware defrag path, and backref walking stuff will
find data reloc tree as refs' parent, and hit the BUG_ON() during COW.
As data reloc tree's data is just for relocation purpose, and will be deleted right
after relocation is done, it's unnecessary to walk those refs belonged to data reloc
tree, it'd be better to skip them.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Remove unused eb parameter from btrfs_item_nr
Signed-off-by: Ross Kirk <ross.kirk@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
struct __prelim_ref is allocated and freed frequently when
walking backref tree, using slab allocater can not only
speed up allocating but also detect memory leaks.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Currently, only add_delayed_refs have to allocate with GFP_ATOMIC,
So just pass arg 'gfp_t' to decide which allocation mode.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
u64 is "unsigned long long" on all architectures now, so there's no need to
cast it when formatting it using the "ll" length modifier.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
make C=2 fs/btrfs/ CF=-D__CHECK_ENDIAN__
I tried to filter out the warnings for which patches have already
been sent to the mailing list, pending for inclusion in btrfs-next.
All these changes should be obviously safe.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Because we don't mess with the offset into the extent for compressed we will
properly find both extents for this case
[extent a][extent b][rest of extent a]
but because we already added a ref for the front half we won't add the inode
information for the second half. This causes us to leak that memory and not
print out the other offset when we do logical-resolve. So fix this by calling
ulist_add_merge and then add our eie to the existing entry if there is one.
With this patch we get both offsets out of logical-resolve. With this and the
other 2 patches I've sent we now pass btrfs/276 on my vm with compress-force=lzo
set. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If you do btrfs inspect-internal logical-resolve on a compressed extent that has
been partly overwritten it won't find anything. This is because we try and
match the extent offset we've searched for based on the extent offset in the
data extent entry. However this doesn't work for compressed extents because the
offsets are for the uncompressed size, not the compressed size. So instead only
do this check if we are not compressed, that way we can get an actual entry for
the physical offset rather than nothing for compressed. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I missed fixing the backref stuff when I introduced the skinny metadata. If you
try and do things like snapshot aware defrag with skinny metadata you are going
to see tons of warnings related to the backref count being less than 0. This is
because the delayed refs will be found for stuff just fine, but it won't find
the skinny metadata extent refs. With this patch I'm not seeing warnings
anymore. Thanks,
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Looking into this backref problem I noticed we're using a macro to what turns
out to essentially be a NULL check to see if we need to search the commit root.
I'm killing this, let's just do what everybody else does and checks if trans ==
NULL. I've also made it so we pass in the path to __resolve_indirect_refs which
will have the search_commit_root flag set properly already and that way we can
avoid allocating another path when we have a perfectly good one to use. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
In the find_parent_nodes(), if read_tree_block() fails, we can
not return directly, we should free some allocated memory otherwise
memory leak happens.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Big patch, but all it does is add statics to functions which
are in fact static, then remove the associated dead-code fallout.
removed functions:
btrfs_iref_to_path()
__btrfs_lookup_delayed_deletion_item()
__btrfs_search_delayed_insertion_item()
__btrfs_search_delayed_deletion_item()
find_eb_for_page()
btrfs_find_block_group()
range_straddles_pages()
extent_range_uptodate()
btrfs_file_extent_length()
btrfs_scrub_cancel_devid()
btrfs_start_transaction_lflush()
btrfs_print_tree() is left because it is used for debugging.
btrfs_start_transaction_lflush() and btrfs_reada_detach() are
left for symmetry.
ulist.c functions are left, another patch will take care of those.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
We kept leaking extent buffers when mounting a broken file system and it turns
out it's because not everybody uses read_tree_block properly. You need to check
and make sure the extent_buffer is uptodate before you use it. This patch fixes
everybody who calls read_tree_block directly to make sure they check that it is
uptodate and free it and return an error if it is not. With this we no longer
leak EB's when things go horribly wrong. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If out of memory happens, we should return -ENOMEM directly to the caller
rather than continue the work.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
__merge_refs() always return 0, it is unnecessary
for the caller to check the return value.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The only error return value of __add_prelim_ref() is -ENOMEM,
just return errors rather than trigger BUG_ON().
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If btrfs_find_all_roots() fails, 'roots' has been freed or 'roots'
fails to allocate. We don't need to free it outside btrfs_find_all_roots()
again.Fix it.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The reason that BUG_ON() happens in these places is just
because of ENOMEM.
We try ro return ENOMEM rather than trigger BUG_ON(), the
caller will abort the transaction thus avoiding the kernel panic.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
When a subvolume is removed, we remove the root item from the root tree,
while the tree blocks and backrefs remain for a while. When backref walking
comes across one of those orphan tree blocks, it can find a backref for a
no longer existing root. This is all good, we only must tolerate
__resolve_indirect_ref returning an error and continue with the good refs
found.
Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
When __merge_refs merges two refs, it is also needed to merge the
inode_list of both refs. Otherwise we have missed backrefs and memory
leaks. This happens for example if two inodes share an extent and
both lie in the same leaf and thus also have the same parent.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Just use WARN_ON rather than an if containing only WARN_ON(1).
A simplified version of the semantic patch that makes this transformation
is as follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
@@
- if (e) WARN_ON(1);
+ WARN_ON(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
To see the problem, create many hardlinks to the same file (120 should do it),
then look up paths by inode with:
ls -i
btrfs inspect inode-resolve -v $ino /mnt/btrfs
I noticed the memory layout of the fspath->val data had some irregularities
(some unnecessary gaps that stop appearing about halfway),
so I'm not sure there aren't any bugs left in it.
In btrfs_find_all_roots' termination condition, we compare the level of the
old buffer we got from btrfs_search_old_slot to the level of the current
root node. We'd better compare it to the level of the rewinded root node.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The iterate_irefs in backref.c is used to build path components from inode
refs. This patch adds code to iterate extended refs as well.
I had modify the callback function signature to abstract out some of the
differences between ref structures. iref_to_path() also needed similar
changes.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
This patch adds basic support for extended inode refs. This includes support
for link and unlink of the refs, which basically gets us support for rename
as well.
Inode creation does not need changing - extended refs are only added after
the ref array is full.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
This is the change of the kernel side.
Translation of logical to inode used to have an upper limit 4k on
inode container's size, but the limit is not large enough for a data
with a great many of refs, so when resolving logical address,
we can end up with
"ioctl ret=0, bytes_left=0, bytes_missing=19944, cnt=510, missed=2493"
This changes to regard 64k as the upper limit and use vmalloc instead of
kmalloc to get memory more easily.
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag.
It is possible to lose our errors because
(-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true.
I'm not sure if it is on purpose, it just looks too hacky if it is.
I'd rather use a real flag and a 'ret' to catch errors.
Acked-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Liu Bo <liub.liubo@gmail.com>
Btrfs send/receive uses the aux field to store inode numbers. On
32 bit machines this may become a problem.
Also fix all users of ulist_add and ulist_add_merged.
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
In iterate_inodes_from_logical() the error result from
extent_from_logical() is patched by mistake. Typically ENOENT is
patched to EINVAL because (-ENOENT & BTRFS_EXTENT_FLAG_TREE_BLOCK)
evaluates to true.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
This is the kernel portion of btrfs send/receive
Conflicts:
fs/btrfs/Makefile
fs/btrfs/backref.h
fs/btrfs/ctree.c
fs/btrfs/ioctl.c
fs/btrfs/ioctl.h
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We've got two mechanisms both required for reliable backref resolving (tree
mod log and holding back delayed refs). You cannot make use of one without
the other. So instead of requiring the user of this mechanism to setup both
correctly, we join them into a single interface.
Additionally, we stop inserting non-blockers into fs_info->tree_mod_seq_list
as we did before, which was of no value.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
When delayed refs exist, btrfs_find_all_roots used to hold the delayed ref
mutex way longer than actually required. We ought to drop it immediately
after we're done collecting all the delayed refs.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
With the tree mod log, we can have a tree that's two levels high, but
btrfs_search_old_slot may still return a path with the tree root at level
one instead. __resolve_indirect_ref must care for this and accept parents in
a lower level than expected.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
add_all_parents did assume that path is already at a correct extent data
item, which may not be true in case of data extents that were partly
rewritten and splitted.
We need to check if we're on a matching extent for every item and only
for the ones after the first. The loop is changed to do this now.
This patch also fixes a bug introduced with commit 3b127fd8 "Btrfs:
remove obsolete btrfs_next_leaf call from __resolve_indirect_ref".
The removal of next_leaf did sometimes result in slot==nritems when
the above described case happens, and thus resulting in invalid values
(e.g. wanted_obejctid) in add_all_parents (leading to missed backrefs
or even crashes).
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
To make sense of the tree mod log, the backref walker not only needs
btrfs_search_old_slot, but it also called btrfs_next_leaf, which in turn was
calling btrfs_search_slot. This obviously didn't give the correct result.
This commit adds btrfs_next_old_leaf, a drop-in replacement for
btrfs_next_leaf with a time_seq parameter. If it is zero, it behaves exactly
like btrfs_next_leaf. If it is non-zero, it will use btrfs_search_old_slot
with this time_seq parameter.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
When resolving indirect refs, we used to call btrfs_next_leaf in case we
didn't find an exact match. While we should find exact matches most of the
time, in case we don't, we must continue searching. Treating those matches
differently depending on the level we're searching doesn't make sense.
Even worse, we might end up searching for a key larger than the largest, in
which case there is no next_leaf and subsequent jobs would fail. This commit
drops the bogous lines.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
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>
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>
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>
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>
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>
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>
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>
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>
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>
init_ipath() allocates btrfs_data_container which is never freed. Free
it in free_ipath() and nuke the comment for init_data_container() - we
can safely free it with kfree().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In commit 4692cf58 we introduced new backref walking code for btrfs. This
assumes we're searching live roots, which requires a transaction context.
While scrubbing, however, we must not join a transaction because this could
deadlock with the commit path. Additionally, what scrub really wants to do
is resolving a logical address in the commit root it's currently checking.
This patch adds support for logical to path resolving on commit roots and
makes scrub use that.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
- We might unlock head->mutex while it was not locked
- We might leave the function without unlocking delayed_refs->lock
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
inode_ref_info() returns 1 when the element wasn't found and < 0 on error,
just like btrfs_search_slot(). In iref_to_path() it's an error when the
inode ref can't be found, thus we return ERR_PTR(ret) in that case. In order
to avoid ERR_PTR(1), we now set ret to -ENOENT in that case.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Added initialization with the declaration of ret. It isn't set later on the
switch-default branch (which should never be taken).
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The old backref iteration code could only safely be used on commit roots.
Besides this limitation, it had bugs in finding the roots for these
references. This commit replaces large parts of it by btrfs_find_all_roots()
which a) really finds all roots and the correct roots, b) works correctly
under heavy file system load, c) considers delayed refs.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This function gets a byte number (a data extent), collects all the leafs
pointing to it and walks up the trees to find all fs roots pointing to those
leafs. It also returns the list of all leafs pointing to that extent.
It does proper locking for the involved trees, can be used on busy file
systems and honors delayed refs.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This patch casts to unsigned long before casting to a pointer and fixes
the following warnings:
fs/btrfs/extent_io.c:2289:20: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
fs/btrfs/ioctl.c:2933:37: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
fs/btrfs/ioctl.c:2937:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
fs/btrfs/ioctl.c:3020:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
fs/btrfs/scrub.c:275:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
fs/btrfs/backref.c:686:27: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The new ioctls to follow backrefs are not clean for 32/64 bit
compat. This reworks them for u64s everywhere. They are brand new, so
there are no problems with changing the interface now.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
These helper functions iterate back references and call a function for each
backref. There is also a function to resolve an inode to a path in the
file system.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>