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857668 commits

Author SHA1 Message Date
Josef Bacik
84fe47a4be btrfs: add enospc debug messages for ticket failure
When debugging weird enospc problems it's handy to be able to dump the
space info when we wake up all tickets, and see what the ticket values
are.  This helped me figure out cases where we were enospc'ing when we
shouldn't have been.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:19 +02:00
Josef Bacik
0096420adb btrfs: do not account global reserve in can_overcommit
We ran into a problem in production where a box with plenty of space was
getting wedged doing ENOSPC flushing.  These boxes only had 20% of the
disk allocated, but their metadata space + global reserve was right at
the size of their metadata chunk.

In this case can_overcommit should be allowing allocations without
problem, but there's logic in can_overcommit that doesn't allow us to
overcommit if there's not enough real space to satisfy the global
reserve.

This is for historical reasons.  Before there were only certain places
we could allocate chunks.  We could go to commit the transaction and not
have enough space for our pending delayed refs and such and be unable to
allocate a new chunk.  This would result in a abort because of ENOSPC.
This code was added to solve this problem.

However since then we've gained the ability to always be able to
allocate a chunk.  So we can easily overcommit in these cases without
risking a transaction abort because of ENOSPC.

Also prior to now the global reserve really would be used because that's
the space we relied on for delayed refs.  With delayed refs being
tracked separately we no longer have to worry about running out of
delayed refs space while committing.  We are much less likely to
exhaust our global reserve space during transaction commit.

Fix the can_overcommit code to simply see if our current usage + what we
want is less than our current free space plus whatever slack space we
have in the disk is.  This solves the problem we were seeing in
production and keeps us from flushing as aggressively as we approach our
actual metadata size usage.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:19 +02:00
Josef Bacik
426551f686 btrfs: use btrfs_try_granting_tickets in update_global_rsv
We have some annoying xfstests tests that will create a very small fs,
fill it up, delete it, and repeat to make sure everything works right.
This trips btrfs up sometimes because we may commit a transaction to
free space, but most of the free metadata space was being reserved by
the global reserve.  So we commit and update the global reserve, but the
space is simply added to bytes_may_use directly, instead of trying to
add it to existing tickets.  This results in ENOSPC when we really did
have space.  Fix this by calling btrfs_try_granting_tickets once we add
back our excess space to wake any pending tickets.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:19 +02:00
Josef Bacik
d792b0f197 btrfs: always reserve our entire size for the global reserve
While messing with the overcommit logic I noticed that sometimes we'd
ENOSPC out when really we should have run out of space much earlier.  It
turns out it's because we'll only reserve up to the free amount left in
the space info for the global reserve, but that doesn't make sense with
overcommit because we could be well above our actual size.  This results
in the global reserve not carving out it's entire reservation, and thus
not putting enough pressure on the rest of the infrastructure to do the
right thing and ENOSPC out at a convenient time.  Fix this by always
taking our full reservation amount for the global reserve.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:19 +02:00
Josef Bacik
3593ce30b5 btrfs: change the minimum global reserve size
It made sense to have the global reserve set at 16M in the past, but
since it is used less nowadays set the minimum size to the number of
items we'll need to update the main trees we update during a transaction
commit, plus some slop area so we can do unlinks if we need to.

In practice this doesn't affect normal file systems, but for xfstests
where we do things like fill up a fs and then rm * it can fall over in
weird ways.  This enables us for more sane behavior at extremely small
file system sizes.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
d05e46497f btrfs: rename btrfs_space_info_add_old_bytes
This name doesn't really fit with how the space reservation stuff works
now, rename it to btrfs_space_info_free_bytes_may_use so it's clear what
the function is doing.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
def936e535 btrfs: remove orig_bytes from reserve_ticket
Now that we do not do partial filling of tickets simply remove
orig_bytes, it is no longer needed.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
00c0135eb8 btrfs: fix may_commit_transaction to deal with no partial filling
Now that we aren't partially filling tickets we may have some slack
space left in the space_info.  We need to account for this in
may_commit_transaction, otherwise we may choose to not commit the
transaction despite it actually having enough space to satisfy our
ticket.

Calculate the free space we have in the space_info, if any, and subtract
this from the ticket we have and use that amount to determine if we will
need to commit to reclaim enough space.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
2341ccd1bf btrfs: rework wake_all_tickets
Now that we no longer partially fill tickets we need to rework
wake_all_tickets to call btrfs_try_to_wakeup_tickets() in order to see
if any subsequent tickets are able to be satisfied.  If our tickets_id
changes we know something happened and we can keep flushing.

Also if we find a ticket that is smaller than the first ticket in our
queue then we want to retry the flushing loop again in case
may_commit_transaction() decides we could satisfy the ticket by
committing the transaction.

Rename this to maybe_fail_all_tickets() while we're at it, to better
reflect what the function is actually doing.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
18fa2284aa btrfs: refactor the ticket wakeup code
Now that btrfs_space_info_add_old_bytes simply checks if we can make the
reservation and updates bytes_may_use, there's no reason to have both
helpers in place.

Factor out the ticket wakeup logic into it's own helper, make
btrfs_space_info_add_old_bytes() update bytes_may_use and then call the
wakeup helper, and replace all calls to btrfs_space_info_add_new_bytes()
with the wakeup helper.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
9118264507 btrfs: stop partially refilling tickets when releasing space
btrfs_space_info_add_old_bytes is used when adding the extra space from
an existing reservation back into the space_info to be used by any
waiting tickets.  In order to keep us from overcommitting we check to
make sure that we can still use this space for our reserve ticket, and
if we cannot we'll simply subtract it from space_info->bytes_may_use.

However this is problematic, because it assumes that only changes to
bytes_may_use would affect our ability to make reservations.  Any
changes to bytes_reserved would be missed.  If we were unable to make a
reservation prior because of reserved space, but that reserved space was
free'd due to unlink or truncate and we were allowed to immediately
reclaim that metadata space we would still ENOSPC.

Consider the example where we create a file with a bunch of extents,
using up 2MiB of actual space for the new tree blocks.  Then we try to
make a reservation of 2MiB but we do not have enough space to make this
reservation.  The iput() occurs in another thread and we remove this
space, and since we did not write the blocks we simply do
space_info->bytes_reserved -= 2MiB.  We would never see this because we
do not check our space info used, we just try to re-use the freed
reservations.

To fix this problem, and to greatly simplify the wakeup code, do away
with this partial refilling nonsense.  Use
btrfs_space_info_add_old_bytes to subtract the reservation from
space_info->bytes_may_use, and then check the ticket against the total
used of the space_info the same way we do with the initial reservation
attempt.

This keeps the reservation logic consistent and solves the problem of
early ENOSPC in the case that we free up space in places other than
bytes_may_use and bytes_pinned.  Thanks,

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:18 +02:00
Josef Bacik
a43c383574 btrfs: add space reservation tracepoint for reserved bytes
I noticed when folding the trace_btrfs_space_reservation() tracepoint
into the btrfs_space_info_update_* helpers that we didn't emit a
tracepoint when doing btrfs_add_reserved_bytes().  I know this is
because we were swapping bytes_may_use for bytes_reserved, so in my mind
there was no reason to have the tracepoint there.  But now there is
because we always emit the unreserve for the bytes_may_use side, and
this would have broken if compression was on anyway.  Add a tracepoint
to cover the bytes_reserved counter so the math still comes out right.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Josef Bacik
f3e75e3805 btrfs: roll tracepoint into btrfs_space_info_update helper
We duplicate this tracepoint everywhere we call these helpers, so update
the helper to have the tracepoint as well.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Josef Bacik
ef1317a1b9 btrfs: do not allow reservations if we have pending tickets
If we already have tickets on the list we don't want to steal their
reservations.  This is a preparation patch for upcoming changes,
technically this shouldn't happen today because of the way we add bytes
to tickets before adding them to the space_info in most cases.

This does not change the FIFO nature of reserve tickets, it simply
allows us to enforce it in a different way.  Previously it was enforced
because any new space would be added to the first ticket on the list,
which would result in new reservations getting a reserve ticket.  This
replaces that mechanism by simply checking to see if we have outstanding
reserve tickets and skipping straight to adding a ticket for our
reservation.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Omar Sandoval
e182163d9c btrfs: stop clearing EXTENT_DIRTY in inode I/O tree
Since commit fee187d9d9 ("Btrfs: do not set EXTENT_DIRTY along with
EXTENT_DELALLOC"), we never set EXTENT_DIRTY in inode->io_tree, so we
can simplify and stop trying to clear it.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Omar Sandoval
f50cb7aff9 btrfs: treat RWF_{,D}SYNC writes as sync for CRCs
The VFS indicates a synchronous write to ->write_iter() via
iocb->ki_flags. The IOCB_{,D}SYNC flags may be set based on the file
(see iocb_flags()) or the RWF_* flags passed to a syscall like
pwritev2() (see kiocb_set_rw_flags()).

However, in btrfs_file_write_iter(), we're checking if a write is
synchronous based only on the file; we use this to decide when to bump
the sync_writers counter and thus do CRCs synchronously. Make sure we do
this for all synchronous writes as determined by the VFS.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add const ]
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Omar Sandoval
c09767a896 btrfs: use correct count in btrfs_file_write_iter()
generic_write_checks() may modify iov_iter_count(), so we must get the
count after the call, not before. Using the wrong one has a couple of
consequences:

1. We check a longer range in check_can_nocow() for nowait than we're
   actually writing.
2. We create extra hole extent maps in btrfs_cont_expand(). As far as I
   can tell, this is harmless, but I might be missing something.

These issues are pretty minor, but let's fix it before something more
important trips on it.

Fixes: edf064e7c6 ("btrfs: nowait aio support")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
David Sterba
c82f823c9b btrfs: tie extent buffer and it's token together
Further simplifaction of the get/set helpers is possible when the token
is uniquely tied to an extent buffer. A condition and an assignment can
be avoided.

The initializations are moved closer to the first use when the extent
buffer is valid. There's one exception in __push_leaf_left where the
token is reused.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
David Sterba
48bc39501a btrfs: assume valid token for btrfs_set/get_token helpers
Now that we can safely assume that the token is always a valid pointer,
remove the branches that check that.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
David Sterba
cb49511328 btrfs: define separate btrfs_set/get_XX helpers
There are helpers for all type widths defined via macro and optionally
can use a token which is a cached pointer to avoid repeated mapping of
the extent buffer.

The token value is known at compile time, when it's valid it's always
address of a local variable, otherwise it's NULL passed by the
token-less helpers.

This can be utilized to remove some branching as the helpers are used
frequenlty.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
Nikolay Borisov
6ff49c6ad2 btrfs: Make btrfs_find_name_in_ext_backref return struct btrfs_inode_extref
btrfs_find_name_in_ext_backref returns either 0/1 depending on whether it
found a backref for the given name. If it returns true then the actual
inode_ref struct is returned in one of its parameters. That's pointless,
instead refactor the function such that it returns either a pointer
to the btrfs_inode_extref or NULL it it didn't find anything. This
streamlines the function calling convention.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
Nikolay Borisov
9bb8407f54 btrfs: Make btrfs_find_name_in_backref return btrfs_inode_ref struct
btrfs_find_name_in_backref returns either 0/1 depending on whether it
found a backref for the given name. If it returns true then the actual
inode_ref struct is returned in one of its parameters. That's pointless,
instead refactor the function such that it returns either a pointer
to the btrfs_inode_ref or NULL it it didn't find anything. This
streamlines the function calling convention.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
David Sterba
1dc990dfd3 btrfs: move dev_stats helpers to volumes.c
The other dev stats functions are already there and the helpers are not
used by anything else.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:16 +02:00
David Sterba
67b61aefce btrfs: move struct io_ctl to free-space-cache.h
The io_ctl structure is used for free space management, and used only by
the v1 space cache code, but unfortunatlly the full definition is
required by block-group.h so it can't be moved to free-space-cache.c
without additional changes.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
David Sterba
18d0f5c6e1 btrfs: move functions for tree compare to send.c
Send is the only user of tree_compare, we can move it there along with
the other helpers and definitions.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
David Sterba
4b231ae474 btrfs: rename and export read_node_slot
Preparatory work for code that will be moved out of ctree and uses this
function.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
David Sterba
8a953348af btrfs: move private raid56 definitions from ctree.h
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
David Sterba
784352fe0b btrfs: move math functions to misc.h
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
David Sterba
602cbe91fb btrfs: move cond_wake_up functions out of ctree
The file ctree.h serves as a header for everything and has become quite
bloated. Split some helpers that are generic and create a new file that
should be the catch-all for code that's not btrfs-specific.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:15 +02:00
Anand Jain
d2979aa25f btrfs: use proper error values on allocation failure in clone_fs_devices
Fix the fake ENOMEM return error code to the actual error in
clone_fs_devices().

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Anand Jain
a06dee4d7e btrfs: proper error handling when invalid device is found in find_next_devid
In a corrupted tree, if search for next devid finds the device with
devid = -1, then report the error -EUCLEAN back to the parent function
to fail gracefully.

The tree checker will not catch this in case the devids are created
using the following script:

  umount /btrfs
  dev1=/dev/sdb
  dev2=/dev/sdc
  mkfs.btrfs -fq -dsingle -msingle $dev1
  mount $dev1 /btrfs

  _fail()
  {
	  echo $1
	  exit 1
  }

  while true; do
	  btrfs dev add -f $dev2 /btrfs || _fail "add failed"
	  btrfs dev del $dev1 /btrfs || _fail "del failed"
	  dev_tmp=$dev1
	  dev1=$dev2
	  dev2=$dev_tmp
  done

With output:

  BTRFS critical (device sdb): corrupt leaf: root=3 block=313739198464 slot=1 devid=1 invalid devid: has=507 expect=[0, 506]
  BTRFS error (device sdb): block=313739198464 write time tree block corruption detected
  BTRFS: error (device sdb) in btrfs_commit_transaction:2268: errno=-5 IO failure (Error while writing out transaction)
  BTRFS warning (device sdb): Skipping commit of aborted transaction.
  BTRFS: error (device sdb) in cleanup_transaction:1827: errno=-5 IO failure

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ add script and messages ]
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Christophe Leroy
3acd48507d btrfs: fix allocation of free space cache v1 bitmap pages
Various notifications of type "BUG kmalloc-4096 () : Redzone
overwritten" have been observed recently in various parts of the kernel.
After some time, it has been made a relation with the use of BTRFS
filesystem and with SLUB_DEBUG turned on.

[   22.809700] BUG kmalloc-4096 (Tainted: G        W        ): Redzone overwritten

[   22.810286] INFO: 0xbe1a5921-0xfbfc06cd. First byte 0x0 instead of 0xcc
[   22.810866] INFO: Allocated in __load_free_space_cache+0x588/0x780 [btrfs] age=22 cpu=0 pid=224
[   22.811193] 	__slab_alloc.constprop.26+0x44/0x70
[   22.811345] 	kmem_cache_alloc_trace+0xf0/0x2ec
[   22.811588] 	__load_free_space_cache+0x588/0x780 [btrfs]
[   22.811848] 	load_free_space_cache+0xf4/0x1b0 [btrfs]
[   22.812090] 	cache_block_group+0x1d0/0x3d0 [btrfs]
[   22.812321] 	find_free_extent+0x680/0x12a4 [btrfs]
[   22.812549] 	btrfs_reserve_extent+0xec/0x220 [btrfs]
[   22.812785] 	btrfs_alloc_tree_block+0x178/0x5f4 [btrfs]
[   22.813032] 	__btrfs_cow_block+0x150/0x5d4 [btrfs]
[   22.813262] 	btrfs_cow_block+0x194/0x298 [btrfs]
[   22.813484] 	commit_cowonly_roots+0x44/0x294 [btrfs]
[   22.813718] 	btrfs_commit_transaction+0x63c/0xc0c [btrfs]
[   22.813973] 	close_ctree+0xf8/0x2a4 [btrfs]
[   22.814107] 	generic_shutdown_super+0x80/0x110
[   22.814250] 	kill_anon_super+0x18/0x30
[   22.814437] 	btrfs_kill_super+0x18/0x90 [btrfs]
[   22.814590] INFO: Freed in proc_cgroup_show+0xc0/0x248 age=41 cpu=0 pid=83
[   22.814841] 	proc_cgroup_show+0xc0/0x248
[   22.814967] 	proc_single_show+0x54/0x98
[   22.815086] 	seq_read+0x278/0x45c
[   22.815190] 	__vfs_read+0x28/0x17c
[   22.815289] 	vfs_read+0xa8/0x14c
[   22.815381] 	ksys_read+0x50/0x94
[   22.815475] 	ret_from_syscall+0x0/0x38

Commit 69d2480456 ("btrfs: use copy_page for copying pages instead of
memcpy") changed the way bitmap blocks are copied. But allthough bitmaps
have the size of a page, they were allocated with kzalloc().

Most of the time, kzalloc() allocates aligned blocks of memory, so
copy_page() can be used. But when some debug options like SLAB_DEBUG are
activated, kzalloc() may return unaligned pointer.

On powerpc, memcpy(), copy_page() and other copying functions use
'dcbz' instruction which provides an entire zeroed cacheline to avoid
memory read when the intention is to overwrite a full line. Functions
like memcpy() are writen to care about partial cachelines at the start
and end of the destination, but copy_page() assumes it gets pages. As
pages are naturally cache aligned, copy_page() doesn't care about
partial lines. This means that when copy_page() is called with a
misaligned pointer, a few leading bytes are zeroed.

To fix it, allocate bitmaps through kmem_cache instead of using kzalloc()
The cache pool is created with PAGE_SIZE alignment constraint.

Reported-by: Erhard F. <erhard_f@mailbox.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204371
Fixes: 69d2480456 ("btrfs: use copy_page for copying pages instead of memcpy")
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to btrfs_free_space_bitmap ]
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Qu Wenruo
62fdaa52a3 btrfs: Detect unbalanced tree with empty leaf before crashing btree operations
[BUG]
With crafted image, btrfs will panic at btree operations:

  kernel BUG at fs/btrfs/ctree.c:3894!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 0 PID: 1138 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9
  RIP: 0010:__push_leaf_left+0x6b6/0x6e0
  RSP: 0018:ffffc0bd4128b990 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffffa0a4ab8f0e38 RCX: 0000000000000000
  RDX: ffffa0a280000000 RSI: 0000000000000000 RDI: ffffa0a4b3814000
  RBP: ffffc0bd4128ba38 R08: 0000000000001000 R09: ffffc0bd4128b948
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000240
  R13: ffffa0a4b556fb60 R14: ffffa0a4ab8f0af0 R15: ffffa0a4ab8f0af0
  FS: 0000000000000000(0000) GS:ffffa0a4b7a00000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f2461c80020 CR3: 000000022b32a006 CR4: 00000000000206f0
  Call Trace:
  ? _cond_resched+0x1a/0x50
  push_leaf_left+0x179/0x190
  btrfs_del_items+0x316/0x470
  btrfs_del_csums+0x215/0x3a0
  __btrfs_free_extent.isra.72+0x5a7/0xbe0
  __btrfs_run_delayed_refs+0x539/0x1120
  btrfs_run_delayed_refs+0xdb/0x1b0
  btrfs_commit_transaction+0x52/0x950
  ? start_transaction+0x94/0x450
  transaction_kthread+0x163/0x190
  kthread+0x105/0x140
  ? btrfs_cleanup_transaction+0x560/0x560
  ? kthread_destroy_worker+0x50/0x50
  ret_from_fork+0x35/0x40
  Modules linked in:
  ---[ end trace c2425e6e89b5558f ]---

[CAUSE]
The offending csum tree looks like this:

  checksum tree key (CSUM_TREE ROOT_ITEM 0)
  node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE
	  ...
	  key (EXTENT_CSUM EXTENT_CSUM 85975040) block 29630464 gen 17
	  key (EXTENT_CSUM EXTENT_CSUM 89911296) block 29642752 gen 17 <<<
	  key (EXTENT_CSUM EXTENT_CSUM 92274688) block 29646848 gen 17
	  ...

  leaf 29630464 items 6 free space 1 generation 17 owner CSUM_TREE
	  item 0 key (EXTENT_CSUM EXTENT_CSUM 85975040) itemoff 3987 itemsize 8
		  range start 85975040 end 85983232 length 8192
	  ...
  leaf 29642752 items 0 free space 3995 generation 17 owner 0
		      ^ empty leaf            invalid owner ^

  leaf 29646848 items 1 free space 602 generation 17 owner CSUM_TREE
	  item 0 key (EXTENT_CSUM EXTENT_CSUM 92274688) itemoff 627 itemsize 3368
		  range start 92274688 end 95723520 length 3448832

So we have a corrupted csum tree where one tree leaf is completely
empty, causing unbalanced btree, thus leading to unexpected btree
balance error.

[FIX]
For this particular case, we handle it in two directions to catch it:
- Check if the tree block is empty through btrfs_verify_level_key()
  So that invalid tree blocks won't be read out through
  btrfs_search_slot() and its variants.

- Check 0 tree owner in tree checker
  NO tree is using 0 as its tree owner, detect it and reject at tree
  block read time.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202821
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Nikolay Borisov
ebc87351e5 btrfs: Deprecate BTRFS_SUBVOL_CREATE_ASYNC flag
Support for asynchronous snapshot creation was originally added in
72fd032e94 ("Btrfs: add SNAP_CREATE_ASYNC ioctl") to cater for
ceph's backend needs. However, since Ceph has deprecated support for
btrfs there is no longer need for that support in btrfs. Additionally,
this was never supported by btrfs-progs, the official userspace tools.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Nikolay Borisov
762bf09893 btrfs: improve error handling in run_delalloc_nocow
Correctly handle failure cases when adding an ordered extents in case
of REGULAR or PREALLOC extents. Remove the BUG_ON.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:14 +02:00
Nikolay Borisov
e8e210075a btrfs: comment and minor simplifications in run_delalloc_nocow
Add a comment explaining why we keep the BUG also use the already read
and cached value of extent ram bytes stored in 'ram_bytes'.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Nikolay Borisov
922f051824 btrfs: streamline code in run_delalloc_nocow in case of inline extents
The extent range check right after the "out_check" label is redundant,
because the only way it can trigger is if we have an inline extent. In
this case it makes more sense to actually move it in the branch
explictly dealing with inlines extents.

What's more, the nested 'if (nocow)' can never be true because for
inline extents we always do COW and there is no chance 'nocow' can be
true, just remove that check.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Nikolay Borisov
bb55f6260b btrfs: simplify extent type checks in run_delalloc_nocow
There is no point in checking the type of the extent again just to set
the 'type' variable, when this check has already been performed before.
Instead, extend the original if branch with an 'else' clause. This
allows to remove one local variable and make it obvious how the code
flow differs for prealloc/regular extents.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Nikolay Borisov
a6bd9cd155 btrfs: improve comments around nocow path
run_delalloc_nocow contains numerous, somewhat subtle, checks when
figuring out whether a particular extent should be CoW'ed or not. This
patch explicitly states the assumptions those checks verify. As a
result also document 2 of the more subtle checks in check_committed_ref
as well.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Nikolay Borisov
3e024846d2 btrfs: refactor variable scope in run_delalloc_nocow
Of the 22 (!!!) local variables declared in this function only 9 have
function-wide context. Of the remaining 13, 12 are needed in the main
while loop of the function and 1 is needed in a tiny if branch, only in
case we have prealloc extent. This commit reduces the lifespan of every
variable to its bare minimum. It also renames the 'nolock' boolean to
freespace_inode to clearly indicate its purpose.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Josef Bacik
bcacf5f3f9 btrfs: only reserve metadata_size for inodes
Historically we reserved worst case for every btree operation, and
generally speaking we want to do that in cases where it could be the
worst case.  However for updating inodes we know the inode items are
already in the tree, so it will only be an update operation and never an
insert operation.  This allows us to always reserve only the
metadata_size amount for inode updates rather than the
insert_metadata_size amount.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Josef Bacik
2bd36e7b4f btrfs: rename the btrfs_calc_*_metadata_size helpers
btrfs_calc_trunc_metadata_size differs from trans_metadata_size in that
it doesn't take into account any splitting at the levels, because
truncate will never split nodes.  However truncate _and_ changing will
never split nodes, so rename btrfs_calc_trunc_metadata_size to
btrfs_calc_metadata_size.  Also btrfs_calc_trans_metadata_size is purely
for inserting items, so rename this to btrfs_calc_insert_metadata_size.
Making these clearer will help when I start using them differently in
upcoming patches.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:13 +02:00
Qu Wenruo
0785a9aacf btrfs: tree-checker: Add EXTENT_DATA_REF check
EXTENT_DATA_REF is a little like DIR_ITEM which contains hash in its
key->offset.

This patch will check the following contents:
- Key->objectid
  Basic alignment check.

- Hash
  Hash of each extent_data_ref item must match key->offset.

- Offset
  Basic alignment check.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Qu Wenruo
e2406a6f13 btrfs: tree-checker: Add simple keyed refs check
For TREE_BLOCK_REF, SHARED_DATA_REF and SHARED_BLOCK_REF we need to
check:
              | TREE_BLOCK_REF | SHARED_BLOCK_REF | SHARED_BLOCK_REF
--------------+----------------+-----------------+------------------
key->objectid |    Alignment   |     Alignment    |    Alignment
key->offset   |    Any value   |     Alignment    |    Alignment
item_size     |        0       |        0         |   sizeof(le32) (*)

*: sizeof(struct btrfs_shared_data_ref)

So introduce a check to check all these 3 key types together.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Qu Wenruo
f82d1c7ca8 btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check
This patch introduces the ability to check extent items.

This check involves:
- key->objectid check
  Basic alignment check.

- key->type check
  Against btrfs_extent_item::type and SKINNY_METADATA feature.

- key->offset alignment check for EXTENT_ITEM

- key->offset check for METADATA_ITEM

- item size check
  Both against minimal size and stepping check.

- btrfs_extent_item check
  Checks its flags and generation.

- btrfs_extent_inline_ref checks
  Against 4 types inline ref.
  Checks bytenr alignment and tree level.

- btrfs_extent_item::refs check
  Check against total refs found in inline refs.

This check would be the most complex single item check due to its nature
of inlined items.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Dan Carpenter
f11369897e btrfs: fix error pointer check in __btrfs_map_block()
The btrfs_get_chunk_map() never returns NULL, it returns error pointers.

Fixes: 89b798ad1b ("btrfs: Use btrfs_get_io_geometry appropriately")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Anand Jain
3b80a984d2 btrfs: dev stat drop useless goto
In the function btrfs_init_dev_stats() goto out is not needed, because the
alloc has failed. So just return -ENOMEM.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Anand Jain
440630ea7c btrfs: dev stats item key conversion per cpu type is not needed
%found_key is not used, drop it since it hasn't been used since the
beginning in 733f4fbbc1 ("Btrfs: read device stats on mount, write
modified ones during commit").

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:12 +02:00
Nikolay Borisov
4f84bd7f99 btrfs: Make reada_tree_block_flagged private
This function is used only for the readahead machinery. It makes no
sense to keep it external to reada.c file. Place it above its sole
caller and make it static. No functional changes.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:11 +02:00
David Sterba
b0c1fe1eaf btrfs: compression: replace set_level callbacks by a common helper
The set_level callbacks do not do anything special and can be replaced
by a helper that uses the levels defined in the tables.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:11 +02:00