The only remaining use of the 'epd' argument in writepage_delalloc is
to reference the extent_io_tree which was set in extent_writepages. Since
it is guaranteed that page->mapping of any page passed to
writepage_delalloc (and __extent_writepage as the sole caller) to be
equal to that passed in extent_writepages we can directly get the
io_tree via the already passed inode (which is also taken from
page->mapping->host). No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If epd::extent_locked is set then writepage_delalloc terminates. Make
this a bit more apparent in the caller by simply bubbling the check up.
This enables to remove epd as an argument to writepage_delalloc in a
future patch. No functional change.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Before btrfs_map_bio submits all stripe bios it does a number of checks
to ensure the device for every stripe is present. However, it doesn't do
a DEV_STATE_MISSING check, instead this is relegated to the lower level
btrfs_schedule_bio (in the async submission case, sync submission
doesn't check DEV_STATE_MISSING at all). Additionally
btrfs_schedule_bios does the duplicate device->bdev check which has
already been performed in btrfs_map_bio.
This patch moves the DEV_STATE_MISSING check in btrfs_map_bio and
removes the duplicate device->bdev check. Doing so ensures that no bio
cloning/submission happens for both async/sync requests in the face of
missing device. This makes the async io submission path slightly shorter
in terms of instruction count. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
dev_replace::replace_state has been set to
BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED (0) in the same function,
So delete the line which sets replace_state = 0;
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The io_err field of struct btrfs_log_ctx is no longer used after the
recent simplification of the fast fsync path, where we now wait for
ordered extents to complete before logging the inode. We did this in
commit b5e6c3e170 ("btrfs: always wait on ordered extents at fsync
time") and commit a2120a473a ("btrfs: clean up the left over
logged_list usage") removed its last use.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We currently are in a loop finding each range (corresponding to a btree
node/leaf) in a log root's extent io tree and then clean it up. This is a
waste of time since we are traversing the extent io tree's rb_tree more
times then needed (one for a range lookup and another for cleaning it up)
without any good reason.
We free the log trees when we are in the critical section of a transaction
commit (the transaction state is set to TRANS_STATE_COMMIT_DOING), so it's
of great convenience to do everything as fast as possible in order to
reduce the time we block other tasks from starting a new transaction.
So fix this by traversing the extent io tree once and cleaning up all its
records in one go while traversing it.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The loop construct in free_extent_buffer was added in
242e18c7c1 ("Btrfs: reduce lock contention on extent buffer locks")
as means of reducing the times the eb lock is taken, the non-last ref
count is decremented and lock is released. As the special handling
of UNMAPPED extent buffers was removed now there is only one decrement
op which is happening for EXTENT_BUFFER_UNMAPPED case.
This commit modifies the loop condition so that in case of UNMAPPED
buffers the eb's lock is taken only if we are 100% sure the eb is going
to be freed by the current executor of the code. Additionally, remove
superfluous ref count ops in btrfs test.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that the whole of btrfs code has been audited for eb reference count
management it's time to remove the hunk in free_extent_buffer that
essentially considered the condition
"eb->ref == 2 && EXTENT_BUFFER_DUMMY"
to equal "eb->ref = 1". Also remove the last location
which takes an extra reference count in alloc_test_extent_buffer.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In qgroup_rescan_leaf a copy is made of the target leaf by calling
btrfs_clone_extent_buffer. The latter allocates a new buffer and
attaches a new set of pages and copies the content of the source buffer.
The new scratch buffer is only used to iterate it's items, it's not
published anywhere and cannot be accessed by a third party.
Hence, it's not necessary to perform any locking on it whatsoever.
Furthermore, remove the extra extent_buffer_get call since the new
buffer is always allocated with a reference count of 1 which is
sufficient here. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When the 2 comparison trees roots are initialised they are private to
the function and already have reference counts of 1 each. There is no
need to further increment the reference count since the cloned buffers
are already accessed via struct btrfs_path. Eventually the 2 paths used
for comparison are going to be released, effectively disposing of the
cloned buffers.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When a rewound buffer is created it already has a ref count of 1 and the
dummy flag set. Then another ref is taken bumping the count to 2.
Finally when this buffer is released from btrfs_release_path the extra
reference is decremented by the special handling code in
free_extent_buffer.
However, this special code is in fact redundant sinca ref count of 1 is
still correct since the buffer is only accessed via btrfs_path struct.
This paves the way forward of removing the special handling in
free_extent_buffer.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
get_old_root used used only by btrfs_search_old_slot to initialise the
path structure. The old root is always a cloned buffer (either via alloc
dummy or via btrfs_clone_extent_buffer) and its reference count is 2: 1
from allocation, 1 from extent_buffer_get call in get_old_root.
This latter explicit ref count acquire operation is in fact unnecessary
since the semantic is such that the newly allocated buffer is handed
over to the btrfs_path for lifetime management. Considering this just
remove the extra extent_buffer_get in get_old_root.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In iterate_inode_exrefs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.
Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In iterate_inode_refs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.
Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In extent-io self test, we need 2 ordered extents at its maximum size to
do the test.
Instead of using the intermediate numbers, use BTRFS_MAX_EXTENT_SIZE for
@max_bytes, and twice @max_bytes for @total_dirty. This should explain
why we need all these magic numbers and prevent people to modify them by
accident.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs has not allowed swap files since commit 35054394c4 ("Btrfs: stop
providing a bmap operation to avoid swapfile corruptions"). However, now
that the proper restrictions are in place, Btrfs can support swap files
through the swap file a_ops, similar to iomap in commit 67482129cd
("iomap: add a swapfile activation function").
For Btrfs, activation needs to make sure that the file can be used as a
swap file, which currently means that it must be fully allocated as
NOCOW with no compression on one device. It must also do the proper
tracking so that ioctls will not interfere with the swap file.
Deactivation clears this tracking.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The Btrfs swap code is going to need it, so give it a btrfs_ prefix and
make it non-static.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A later patch will implement swap file support for Btrfs, but before we
do that, we need to make sure that the various Btrfs ioctls cannot
change a swap file.
When a swap file is active, we must make sure that the extents of the
file are not moved and that they don't become shared. That means that
the following are not safe:
- chattr +c (enable compression)
- reflink
- dedupe
- snapshot
- defrag
Don't allow those to happen on an active swap file.
Additionally, balance, resize, device remove, and device replace are
also unsafe if they affect an active swapfile. Add a red-black tree of
block groups and devices which contain an active swapfile. Relocation
checks each block group against this tree and skips it or errors out for
balance or resize, respectively. Device remove and device replace check
the tree for the device they will operate on.
Note that we don't have to worry about chattr -C (disable nocow), which
we ignore for non-empty files, because an active swapfile must be
non-empty and can't be truncated. We also don't have to worry about
autodefrag because it's only done on COW files. Truncate and fallocate
are already taken care of by the generic code. Device add doesn't do
relocation so it's not an issue, either.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is the counterpart to merge_extent_hook, similarly, it's used only
for data/freespace inodes so let's remove it, rename it and call it
directly where necessary. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This callback is used only for data and free space inodes. Such inodes
are guaranteed to have their extent_io_tree::private_data set to the
inode struct. Exploit this fact to directly call the function. Also give
it a more descriptive name. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is the counterpart to ex-set_bit_hook (now btrfs_set_delalloc_extent),
similar to what was done before remove clear_bit_hook and rename the
function. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This callback is used to properly account delalloc extents for data
inodes (ordinary file inodes and freespace v1 inodes). Those can be
easily identified since they have their extent_io trees ->private_data
member point to the inode. Let's exploit this fact to remove the
needless indirection through extent_io_hooks and directly call the
function. Also give the function a name which reflects its purpose -
btrfs_set_delalloc_extent.
This patch also modified test_find_delalloc so that the extent_io_tree
used for testing doesn't have its ->private_data set which would have
caused a crash in btrfs_set_delalloc_extent due to the btrfs_inode->root
member not being initialised. The old version of the code also didn't
call set_bit_hook since the extent_io ops weren't set for the inode. No
functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This callback was only used in debug builds by btrfs_leak_debug_check.
A better approach is to move its implementation in
btrfs_leak_debug_check and ensure the latter is only executed for extent
tree which have ->private_data set i.e. relate to a data node and not
the btree one. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This callback is ony ever called for data page writeout so there is no
need to actually abstract it via extent_io_ops. Lets just export it,
remove the definition of the callback and call it directly in the
functions that invoke the callback. Also rename the function to
btrfs_writepage_endio_finish_ordered since what it really does is
account finished io in the ordered extent data structures. No
functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This hook is called only from __extent_writepage_io which is already
called only from the data page writeout path. So there is no need to
make an indirect call via extent_io_ops. This patch just removes the
callback definition, exports the callback function and calls it directly
at the only call site. Also give the function a more descriptive name.
No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This callback is called only from writepage_delalloc which in turn is
guaranteed to be called from the data page writeout path. In the end
there is no reason to have the call to this function to be indrected via
the extent_io_ops structure. This patch removes the callback definition,
exports the function and calls it directly. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to btrfs_run_delalloc_range ]
Signed-off-by: David Sterba <dsterba@suse.com>
This will be used in future patches that remove the optional
extent_io_ops callbacks.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add extra dev extent end check against device boundary.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Enhance btrfs_verify_dev_extents() to remember previous checked dev
extents, so it can verify no dev extents can overlap.
Analysis from Hans:
"Imagine allocating a DATA|DUP chunk.
In the chunk allocator, we first set...
max_stripe_size = SZ_1G;
max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE
... which is 10GiB.
Then...
/* we don't want a chunk larger than 10% of writeable space */
max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
max_chunk_size);
Imagine we only have one 7880MiB block device in this filesystem. Now
max_chunk_size is down to 788MiB.
The next step in the code is to search for max_stripe_size * dev_stripes
amount of free space on the device, which is in our example 1GiB * 2 =
2GiB. Imagine the device has exactly 1578MiB free in one contiguous
piece. This amount of bytes will be put in devices_info[ndevs - 1].max_avail
Next we recalculate the stripe_size (which is actually the device extent
length), based on the actual maximum amount of available raw disk space:
stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);
stripe_size is now 789MiB
Next we do...
data_stripes = num_stripes / ncopies
...where data_stripes ends up as 1, because num_stripes is 2 (the amount
of device extents we're going to have), and DUP has ncopies 2.
Next there's a check...
if (stripe_size * data_stripes > max_chunk_size)
...which matches because 789MiB * 1 > 788MiB.
We go into the if code, and next is...
stripe_size = div_u64(max_chunk_size, data_stripes);
...which resets stripe_size to max_chunk_size: 788MiB
Next is a fun one...
/* bump the answer up to a 16MB boundary */
stripe_size = round_up(stripe_size, SZ_16M);
...which changes stripe_size from 788MiB to 800MiB.
We're not done changing stripe_size yet...
/* But don't go higher than the limits we found while searching
* for free extents
*/
stripe_size = min(devices_info[ndevs - 1].max_avail,
stripe_size);
This is bad. max_avail is twice the stripe_size (we need to fit 2 device
extents on the same device for DUP).
The result here is that 800MiB < 1578MiB, so it's unchanged. However,
the resulting DUP chunk will need 1600MiB disk space, which isn't there,
and the second dev_extent might extend into the next thing (next
dev_extent? end of device?) for 22MiB.
The last shown line of code relies on a situation where there's twice
the value of stripe_size present as value for the variable stripe_size
when it's DUP. This was actually the case before commit 92e222df7b
"btrfs: alloc_chunk: fix DUP stripe size handling", from which I quote:
"[...] in the meantime there's a check to see if the stripe_size does
not exceed max_chunk_size. Since during this check stripe_size is twice
the amount as intended, the check will reduce the stripe_size to
max_chunk_size if the actual correct to be used stripe_size is more than
half the amount of max_chunk_size."
In the previous version of the code, the 16MiB alignment (why is this
done, by the way?) would result in a 50% chance that it would actually
do an 8MiB alignment for the individual dev_extents, since it was
operating on double the size. Does this matter?
Does it matter that stripe_size can be set to anything which is not
16MiB aligned because of the amount of remaining available disk space
which is just taken?
What is the main purpose of this round_up?
The most straightforward thing to do seems something like...
stripe_size = min(
div_u64(devices_info[ndevs - 1].max_avail, dev_stripes),
stripe_size
)
..just putting half of the max_avail into stripe_size."
Link: https://lore.kernel.org/linux-btrfs/b3461a38-e5f8-f41d-c67c-2efac8129054@mendix.com/
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ add analysis from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
We have a complex loop design for find_free_extent(), that has different
behavior for each loop, some even includes new chunk allocation.
Instead of putting such a long code into find_free_extent() and makes it
harder to read, just extract them into find_free_extent_update_loop().
With all the cleanups, the main find_free_extent() should be pretty
barebone:
find_free_extent()
|- Iterate through all block groups
| |- Get a valid block group
| |- Try to do clustered allocation in that block group
| |- Try to do unclustered allocation in that block group
| |- Check if the result is valid
| | |- If valid, then exit
| |- Jump to next block group
|
|- Push harder to find free extents
|- If not found, re-iterate all block groups
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
[ copy callchain from changelog to function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
This patch will extract unclsutered extent allocation code into
find_free_extent_unclustered().
And this helper function will use return value to indicate what to do
next.
This should make find_free_extent() a little easier to read.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
[Update merge conflict with fb5c39d7a8 ("btrfs: don't use ctl->free_space for max_extent_size")]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have two main methods to find free extents inside a block group:
1) clustered allocation
2) unclustered allocation
This patch will extract the clustered allocation into
find_free_extent_clustered() to make it a little easier to read.
Instead of jumping between different labels in find_free_extent(), the
helper function will use return value to indicate different behavior.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of tons of different local variables in find_free_extent(),
extract them into find_free_extent_ctl structure, and add better
explanation for them.
Some modification may looks redundant, but will later greatly simplify
function parameter list during find_free_extent() refactor.
Also add two comments to co-operate with fb5c39d7a8 ("btrfs: don't use
ctl->free_space for max_extent_size"), to make ffe_ctl->max_extent_size
update more reader-friendly.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce a new wrapper update_bytes_pinned to replace open coded
bytes_pinned modifiers. Now the underflows of space_info::bytes_pinned
get detected and reported.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Although we have space_info::bytes_may_use underflow detection in
btrfs_free_reserved_data_space_noquota(), we have more callers who are
subtracting number from space_info::bytes_may_use.
So instead of doing underflow detection for every caller, introduce a
new wrapper update_bytes_may_use() to replace open coded bytes_may_use
modifiers.
This also introduce a macro to declare more wrappers, but currently
space_info::bytes_may_use is the mostly interesting one.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Tracking pending ordered extents per transaction was introduced in commit
50d9aa99bd ("Btrfs: make sure logged extents complete in the current
transaction V3") and later updated in commit 161c3549b4 ("Btrfs: change
how we wait for pending ordered extents").
However now that on fsync we always wait for ordered extents to complete
before logging, done in commit 5636cf7d6d ("btrfs: remove the logged
extents infrastructure"), we no longer need the stuff to track for pending
ordered extents, which was not completely removed in the mentioned commit.
So remove the remaining of the pending ordered extents infrastructure.
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The logged_start and logged_end variables, at btrfs_log_changed_extents,
were added in commit 8c6c592831 ("btrfs: log csums for all modified
extents"). However since the recent simplification for fsync, which makes
us wait for all ordered extents to complete before logging extents, we
no longer need those variables. Commit a2120a473a ("btrfs: clean up the
left over logged_list usage") forgot to remove them.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"A patch in 4.19 introduced a sanity check that was too strict and a
filesystem cannot be mounted.
This happens for filesystems with more than 10 devices and has been
reported by a few users so we need the fix to propagate to stable"
* tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
[BUG]
A completely valid btrfs will refuse to mount, with error message like:
BTRFS critical (device sdb2): corrupt leaf: root=2 block=239681536 slot=172 \
bg_start=12018974720 bg_len=10888413184, invalid block group size, \
have 10888413184 expect (0, 10737418240]
This has been reported several times as the 4.19 kernel is now being
used. The filesystem refuses to mount, but is otherwise ok and booting
4.18 is a workaround.
Btrfs check returns no error, and all kernels used on this fs is later
than 2011, which should all have the 10G size limit commit.
[CAUSE]
For a 12 devices btrfs, we could allocate a chunk larger than 10G due to
stripe stripe bump up.
__btrfs_alloc_chunk()
|- max_stripe_size = 1G
|- max_chunk_size = 10G
|- data_stripe = 11
|- if (1G * 11 > 10G) {
stripe_size = 976128930;
stripe_size = round_up(976128930, SZ_16M) = 989855744
However the final stripe_size (989855744) * 11 = 10888413184, which is
still larger than 10G.
[FIX]
For the comprehensive check, we need to do the full check at chunk read
time, and rely on bg <-> chunk mapping to do the check.
We could just skip the length check for now.
Fixes: fce466eab7 ("btrfs: tree-checker: Verify block_group_item")
Cc: stable@vger.kernel.org # v4.19+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Some of these bugs are being hit during testing so we'd like to get
them merged, otherwise there are usual stability fixes for stable
trees"
* tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: relocation: set trans to be NULL after ending transaction
Btrfs: fix race between enabling quotas and subvolume creation
Btrfs: send, fix infinite loop due to directory rename dependencies
Btrfs: ensure path name is null terminated at btrfs_control_ioctl
Btrfs: fix rare chances for data loss when doing a fast fsync
btrfs: Always try all copies when reading extent buffers
The function relocate_block_group calls btrfs_end_transaction to release
trans when update_backref_cache returns 1, and then continues the loop
body. If btrfs_block_rsv_refill fails this time, it will jump out the
loop and the freed trans will be accessed. This may result in a
use-after-free bug. The patch assigns NULL to trans after trans is
released so that it will not be accessed.
Fixes: 0647bf564f ("Btrfs: improve forever loop when doing balance relocation")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have a race between enabling quotas end subvolume creation that cause
subvolume creation to fail with -EINVAL, and the following diagram shows
how it happens:
CPU 0 CPU 1
btrfs_ioctl()
btrfs_ioctl_quota_ctl()
btrfs_quota_enable()
mutex_lock(fs_info->qgroup_ioctl_lock)
btrfs_ioctl()
create_subvol()
btrfs_qgroup_inherit()
-> save fs_info->quota_root
into quota_root
-> stores a NULL value
-> tries to lock the mutex
qgroup_ioctl_lock
-> blocks waiting for
the task at CPU0
-> sets BTRFS_FS_QUOTA_ENABLED in fs_info
-> sets quota_root in fs_info->quota_root
(non-NULL value)
mutex_unlock(fs_info->qgroup_ioctl_lock)
-> checks quota enabled
flag is set
-> returns -EINVAL because
fs_info->quota_root was
NULL before it acquired
the mutex
qgroup_ioctl_lock
-> ioctl returns -EINVAL
Returning -EINVAL to user space will be confusing if all the arguments
passed to the subvolume creation ioctl were valid.
Fix it by grabbing the value from fs_info->quota_root after acquiring
the mutex.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When doing an incremental send, due to the need of delaying directory move
(rename) operations we can end up in infinite loop at
apply_children_dir_moves().
An example scenario that triggers this problem is described below, where
directory names correspond to the numbers of their respective inodes.
Parent snapshot:
.
|--- 261/
|--- 271/
|--- 266/
|--- 259/
|--- 260/
| |--- 267
|
|--- 264/
| |--- 258/
| |--- 257/
|
|--- 265/
|--- 268/
|--- 269/
| |--- 262/
|
|--- 270/
|--- 272/
| |--- 263/
| |--- 275/
|
|--- 274/
|--- 273/
Send snapshot:
.
|-- 275/
|-- 274/
|-- 273/
|-- 262/
|-- 269/
|-- 258/
|-- 271/
|-- 268/
|-- 267/
|-- 270/
|-- 259/
| |-- 265/
|
|-- 272/
|-- 257/
|-- 260/
|-- 264/
|-- 263/
|-- 261/
|-- 266/
When processing inode 257 we delay its move (rename) operation because its
new parent in the send snapshot, inode 272, was not yet processed. Then
when processing inode 272, we delay the move operation for that inode
because inode 274 is its ancestor in the send snapshot. Finally we delay
the move operation for inode 274 when processing it because inode 275 is
its new parent in the send snapshot and was not yet moved.
When finishing processing inode 275, we start to do the move operations
that were previously delayed (at apply_children_dir_moves()), resulting in
the following iterations:
1) We issue the move operation for inode 274;
2) Because inode 262 depended on the move operation of inode 274 (it was
delayed because 274 is its ancestor in the send snapshot), we issue the
move operation for inode 262;
3) We issue the move operation for inode 272, because it was delayed by
inode 274 too (ancestor of 272 in the send snapshot);
4) We issue the move operation for inode 269 (it was delayed by 262);
5) We issue the move operation for inode 257 (it was delayed by 272);
6) We issue the move operation for inode 260 (it was delayed by 272);
7) We issue the move operation for inode 258 (it was delayed by 269);
8) We issue the move operation for inode 264 (it was delayed by 257);
9) We issue the move operation for inode 271 (it was delayed by 258);
10) We issue the move operation for inode 263 (it was delayed by 264);
11) We issue the move operation for inode 268 (it was delayed by 271);
12) We verify if we can issue the move operation for inode 270 (it was
delayed by 271). We detect a path loop in the current state, because
inode 267 needs to be moved first before we can issue the move
operation for inode 270. So we delay again the move operation for
inode 270, this time we will attempt to do it after inode 267 is
moved;
13) We issue the move operation for inode 261 (it was delayed by 263);
14) We verify if we can issue the move operation for inode 266 (it was
delayed by 263). We detect a path loop in the current state, because
inode 270 needs to be moved first before we can issue the move
operation for inode 266. So we delay again the move operation for
inode 266, this time we will attempt to do it after inode 270 is
moved (its move operation was delayed in step 12);
15) We issue the move operation for inode 267 (it was delayed by 268);
16) We verify if we can issue the move operation for inode 266 (it was
delayed by 270). We detect a path loop in the current state, because
inode 270 needs to be moved first before we can issue the move
operation for inode 266. So we delay again the move operation for
inode 266, this time we will attempt to do it after inode 270 is
moved (its move operation was delayed in step 12). So here we added
again the same delayed move operation that we added in step 14;
17) We attempt again to see if we can issue the move operation for inode
266, and as in step 16, we realize we can not due to a path loop in
the current state due to a dependency on inode 270. Again we delay
inode's 266 rename to happen after inode's 270 move operation, adding
the same dependency to the empty stack that we did in steps 14 and 16.
The next iteration will pick the same move dependency on the stack
(the only entry) and realize again there is still a path loop and then
again the same dependency to the stack, over and over, resulting in
an infinite loop.
So fix this by preventing adding the same move dependency entries to the
stack by removing each pending move record from the red black tree of
pending moves. This way the next call to get_pending_dir_moves() will
not return anything for the current parent inode.
A test case for fstests, with this reproducer, follows soon.
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Wrote changelog with example and more clear explanation]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We were using the path name received from user space without checking that
it is null terminated. While btrfs-progs is well behaved and does proper
validation and null termination, someone could call the ioctl and pass
a non-null terminated patch, leading to buffer overrun problems in the
kernel. The ioctl is protected by CAP_SYS_ADMIN.
So just set the last byte of the path to a null character, similar to what
we do in other ioctls (add/remove/resize device, snapshot creation, etc).
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After the simplification of the fast fsync patch done recently by commit
b5e6c3e170 ("btrfs: always wait on ordered extents at fsync time") and
commit e7175a6927 ("btrfs: remove the wait ordered logic in the
log_one_extent path"), we got a very short time window where we can get
extents logged without writeback completing first or extents logged
without logging the respective data checksums. Both issues can only happen
when doing a non-full (fast) fsync.
As soon as we enter btrfs_sync_file() we trigger writeback, then lock the
inode and then wait for the writeback to complete before starting to log
the inode. However before we acquire the inode's lock and after we started
writeback, it's possible that more writes happened and dirtied more pages.
If that happened and those pages get writeback triggered while we are
logging the inode (for example, the VM subsystem triggering it due to
memory pressure, or another concurrent fsync), we end up seeing the
respective extent maps in the inode's list of modified extents and will
log matching file extent items without waiting for the respective
ordered extents to complete, meaning that either of the following will
happen:
1) We log an extent after its writeback finishes but before its checksums
are added to the csum tree, leading to -EIO errors when attempting to
read the extent after a log replay.
2) We log an extent before its writeback finishes.
Therefore after the log replay we will have a file extent item pointing
to an unwritten extent (and without the respective data checksums as
well).
This could not happen before the fast fsync patch simplification, because
for any extent we found in the list of modified extents, we would wait for
its respective ordered extent to finish writeback or collect its checksums
for logging if it did not complete yet.
Fix this by triggering writeback again after acquiring the inode's lock
and before waiting for ordered extents to complete.
Fixes: e7175a6927 ("btrfs: remove the wait ordered logic in the log_one_extent path")
Fixes: b5e6c3e170 ("btrfs: always wait on ordered extents at fsync time")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When a metadata read is served the endio routine btree_readpage_end_io_hook
is called which eventually runs the tree-checker. If tree-checker fails
to validate the read eb then it sets EXTENT_BUFFER_CORRUPT flag. This
leads to btree_read_extent_buffer_pages wrongly assuming that all
available copies of this extent buffer are wrong and failing prematurely.
Fix this modify btree_read_extent_buffer_pages to read all copies of
the data.
This failure was exhibitted in xfstests btrfs/124 which would
spuriously fail its balance operations. The reason was that when balance
was run following re-introduction of the missing raid1 disk
__btrfs_map_block would map the read request to stripe 0, which
corresponded to devid 2 (the disk which is being removed in the test):
item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 3553624064) itemoff 15975 itemsize 112
length 1073741824 owner 2 stripe_len 65536 type DATA|RAID1
io_align 65536 io_width 65536 sector_size 4096
num_stripes 2 sub_stripes 1
stripe 0 devid 2 offset 2156920832
dev_uuid 8466c350-ed0c-4c3b-b17d-6379b445d5c8
stripe 1 devid 1 offset 3553624064
dev_uuid 1265d8db-5596-477e-af03-df08eb38d2ca
This caused read requests for a checksum item that to be routed to the
stale disk which triggered the aforementioned logic involving
EXTENT_BUFFER_CORRUPT flag. This then triggered cascading failures of
the balance operation.
Fixes: a826d6dcb3 ("Btrfs: check items for correctness as we search")
CC: stable@vger.kernel.org # 4.4+
Suggested-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Several fixes to recent release (4.19, fixes tagged for stable) and
other fixes"
* tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix missing delayed iputs on unmount
Btrfs: fix data corruption due to cloning of eof block
Btrfs: fix infinite loop on inode eviction after deduplication of eof block
Btrfs: fix deadlock on tree root leaf when finding free extent
btrfs: avoid link error with CONFIG_NO_AUTO_INLINE
btrfs: tree-checker: Fix misleading group system information
Btrfs: fix missing data checksums after a ranged fsync (msync)
btrfs: fix pinned underflow after transaction aborted
Btrfs: fix cur_offset in the error case for nocow
There's a race between close_ctree() and cleaner_kthread().
close_ctree() sets btrfs_fs_closing(), and the cleaner stops when it
sees it set, but this is racy; the cleaner might have already checked
the bit and could be cleaning stuff. In particular, if it deletes unused
block groups, it will create delayed iputs for the free space cache
inodes. As of "btrfs: don't run delayed_iputs in commit", we're no
longer running delayed iputs after a commit. Therefore, if the cleaner
creates more delayed iputs after delayed iputs are run in
btrfs_commit_super(), we will leak inodes on unmount and get a busy
inode crash from the VFS.
Fix it by parking the cleaner before we actually close anything. Then,
any remaining delayed iputs will always be handled in
btrfs_commit_super(). This also ensures that the commit in close_ctree()
is really the last commit, so we can get rid of the commit in
cleaner_kthread().
The fstest/generic/475 followed by 476 can trigger a crash that
manifests as a slab corruption caused by accessing the freed kthread
structure by a wake up function. Sample trace:
[ 5657.077612] BUG: unable to handle kernel NULL pointer dereference at 00000000000000cc
[ 5657.079432] PGD 1c57a067 P4D 1c57a067 PUD da10067 PMD 0
[ 5657.080661] Oops: 0000 [#1] PREEMPT SMP
[ 5657.081592] CPU: 1 PID: 5157 Comm: fsstress Tainted: G W 4.19.0-rc8-default+ #323
[ 5657.083703] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
[ 5657.086577] RIP: 0010:shrink_page_list+0x2f9/0xe90
[ 5657.091937] RSP: 0018:ffffb5c745c8f728 EFLAGS: 00010287
[ 5657.092953] RAX: 0000000000000074 RBX: ffffb5c745c8f830 RCX: 0000000000000000
[ 5657.094590] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a8747fdf3d0
[ 5657.095987] RBP: ffffb5c745c8f9e0 R08: 0000000000000000 R09: 0000000000000000
[ 5657.097159] R10: ffff9a8747fdf5e8 R11: 0000000000000000 R12: ffffb5c745c8f788
[ 5657.098513] R13: ffff9a877f6ff2c0 R14: ffff9a877f6ff2c8 R15: dead000000000200
[ 5657.099689] FS: 00007f948d853b80(0000) GS:ffff9a877d600000(0000) knlGS:0000000000000000
[ 5657.101032] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5657.101953] CR2: 00000000000000cc CR3: 00000000684bd000 CR4: 00000000000006e0
[ 5657.103159] Call Trace:
[ 5657.103776] shrink_inactive_list+0x194/0x410
[ 5657.104671] shrink_node_memcg.constprop.84+0x39a/0x6a0
[ 5657.105750] shrink_node+0x62/0x1c0
[ 5657.106529] try_to_free_pages+0x1a4/0x500
[ 5657.107408] __alloc_pages_slowpath+0x2c9/0xb20
[ 5657.108418] __alloc_pages_nodemask+0x268/0x2b0
[ 5657.109348] kmalloc_large_node+0x37/0x90
[ 5657.110205] __kmalloc_node+0x236/0x310
[ 5657.111014] kvmalloc_node+0x3e/0x70
Fixes: 30928e9baa ("btrfs: don't run delayed_iputs in commit")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add trace ]
Signed-off-by: David Sterba <dsterba@suse.com>
We currently allow cloning a range from a file which includes the last
block of the file even if the file's size is not aligned to the block
size. This is fine and useful when the destination file has the same size,
but when it does not and the range ends somewhere in the middle of the
destination file, it leads to corruption because the bytes between the EOF
and the end of the block have undefined data (when there is support for
discard/trimming they have a value of 0x00).
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ export foo_size=$((256 * 1024 + 100))
$ xfs_io -f -c "pwrite -S 0x3c 0 $foo_size" /mnt/foo
$ xfs_io -f -c "pwrite -S 0xb5 0 1M" /mnt/bar
$ xfs_io -c "reflink /mnt/foo 0 512K $foo_size" /mnt/bar
$ od -A d -t x1 /mnt/bar
0000000 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
*
0524288 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c
*
0786528 3c 3c 3c 3c 00 00 00 00 00 00 00 00 00 00 00 00
0786544 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0790528 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
*
1048576
The bytes in the range from 786532 (512Kb + 256Kb + 100 bytes) to 790527
(512Kb + 256Kb + 4Kb - 1) got corrupted, having now a value of 0x00 instead
of 0xb5.
This is similar to the problem we had for deduplication that got recently
fixed by commit de02b9f6bb ("Btrfs: fix data corruption when
deduplicating between different files").
Fix this by not allowing such operations to be performed and return the
errno -EINVAL to user space. This is what XFS is doing as well at the VFS
level. This change however now makes us return -EINVAL instead of
-EOPNOTSUPP for cases where the source range maps to an inline extent and
the destination range's end is smaller then the destination file's size,
since the detection of inline extents is done during the actual process of
dropping file extent items (at __btrfs_drop_extents()). Returning the
-EINVAL error is done early on and solely based on the input parameters
(offsets and length) and destination file's size. This makes us consistent
with XFS and anyone else supporting cloning since this case is now checked
at a higher level in the VFS and is where the -EINVAL will be returned
from starting with kernel 4.20 (the VFS changed was introduced in 4.20-rc1
by commit 07d19dc9fb ("vfs: avoid problematic remapping requests into
partial EOF block"). So this change is more geared towards stable kernels,
as it's unlikely the new VFS checks get removed intentionally.
A test case for fstests follows soon, as well as an update to filter
existing tests that expect -EOPNOTSUPP to accept -EINVAL as well.
CC: <stable@vger.kernel.org> # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
