btrfs: remove the pg_offset parameter from btrfs_get_extent()

The parameter @pg_offset of btrfs_get_extent() is only utilized for
inlined extent, and we already have an ASSERT() and tree-checker, to
make sure we can only get inline extent at file offset 0.

Any invalid inline extent with non-zero file offset would be rejected by
tree-checker in the first place.

Thus the @pg_offset parameter is not really necessary, just remove it.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: use the flags of an extent map to identify the compression type

Currently, in struct extent_map, we use an unsigned int (32 bits) to
identify the compression type of an extent and an unsigned long (64 bits
on a 64 bits platform, 32 bits otherwise) for flags. We are only using
6 different flags, so an unsigned long is excessive and we can use flags
to identify the compression type instead of using a dedicated 32 bits
field.

We can easily have tens or hundreds of thousands (or more) of extent maps
on busy and large filesystems, specially with compression enabled or many
or large files with tons of small extents. So it's convenient to have the
extent_map structure as small as possible in order to use less memory.

So remove the compression type field from struct extent_map, use flags
to identify the compression type and shorten the flags field from an
unsigned long to a u32. This saves 8 bytes (on 64 bits platforms) and
reduces the size of the structure from 136 bytes down to 128 bytes, using
now only two cache lines, and increases the number of extent maps we can
have per 4K page from 30 to 32. By using a u32 for the flags instead of
an unsigned long, we no longer use test_bit(), set_bit() and clear_bit(),
but that level of atomicity is not needed as most flags are never cleared
once set (before adding an extent map to the tree), and the ones that can
be cleared or set after an extent map is added to the tree, are always
performed while holding the write lock on the extent map tree, while the
reader holds a lock on the tree or tests for a flag that never changes
once the extent map is in the tree (such as compression flags).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: abort transaction on generation mismatch when marking eb as dirty

When marking an extent buffer as dirty, at btrfs_mark_buffer_dirty(),
we check if its generation matches the running transaction and if not we
just print a warning. Such mismatch is an indicator that something really
went wrong and only printing a warning message (and stack trace) is not
enough to prevent a corruption. Allowing a transaction to commit with such
an extent buffer will trigger an error if we ever try to read it from disk
due to a generation mismatch with its parent generation.

So abort the current transaction with -EUCLEAN if we notice a generation
mismatch. For this we need to pass a transaction handle to
btrfs_mark_buffer_dirty() which is always available except in test code,
in which case we can pass NULL since it operates on dummy extent buffers
and all test roots have a single node/leaf (root node at level 0).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: selftests: remove impossible inline extent at non-zero file offset

In our inode-tests.c, we create an inline offset at file offset 5, which
is no longer possible since the introduction of tree-checker.

Thus I don't think we should spend time maintaining some corner cases
which are already ruled out by tree-checker.

So this patch will:

- Change the inline extent to start at file offset 0

Also change its length to 6 to cover the original length

- Add an extra ASSERT() for btrfs_add_extent_mapping()

This is to make sure tree-checker is working correctly.

- Update the inode selftest

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: move accessor helpers into accessors.h

This is a large patch, but because they're all macros it's impossible to
split up. Simply copy all of the item accessors in ctree.h and paste
them in accessors.h, and then update any files to include the header so
everything compiles.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ reformat comments, style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: move btrfs_drop_extent_cache() to extent_map.c

The function btrfs_drop_extent_cache() doesn't really belong at file.c
because what it does is drop a range of extent maps for a file range.
It directly allocates and manipulates extent maps, by dropping,
splitting and replacing them in an extent map tree, so it should be
located at extent_map.c, where all manipulations of an extent map tree
and its extent maps are supposed to be done.

So move it out of file.c and into extent_map.c. Additionally do the
following changes:

1) Rename it into btrfs_drop_extent_map_range(), as this makes it more
clear about what it does. The term "cache" is a bit confusing as it's
not widely used, "extent maps" or "extent mapping" is much more common;

2) Change its 'skip_pinned' argument from int to bool;

3) Turn several of its local variables from int to bool, since they are
used as booleans;

4) Move the declaration of some variables out of the function's main
scope and into the scopes where they are used;

5) Remove pointless assignment of false to 'modified' early in the while
loop, as later that variable is set and it's not used before that
second assignment;

6) Remove checks for NULL before calling free_extent_map().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: replace delete argument with EXTENT_CLEAR_ALL_BITS

Instead of taking up a whole argument to indicate we're clearing
everything in a range, simply add another EXTENT bit to control this,
and then update all the callers to drop this argument from the
clear_extent_bit variants.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: remove the wake argument from clear_extent_bits

This is only used in the case that we are clearing EXTENT_LOCKED, so
infer this value from the bits passed in instead of taking it as an
argument.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: unexport setup_items_for_insert()

Since setup_items_for_insert() is not used anymore outside of ctree.c,
make it static and remove its prototype from ctree.h. This also requires
to move the definition of setup_item_for_insert() from ctree.h to ctree.c
and move down btrfs_duplicate_item() so that it's defined after
setup_items_for_insert().

Further, since setup_item_for_insert() is used outside ctree.c, rename it
to btrfs_setup_item_for_insert().

This patch is part of a small patchset that is comprised of the following
patches:

btrfs: loop only once over data sizes array when inserting an item batch
btrfs: unexport setup_items_for_insert()
btrfs: use single bulk copy operations when logging directories

This is patch 2/3 and performance results, and the specific tests, are
included in the changelog of patch 3/3.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: loop only once over data sizes array when inserting an item batch

When inserting a batch of items into a btree, we end up looping over the
data sizes array 3 times:

1) Once in the caller of btrfs_insert_empty_items(), when it populates the
array with the data sizes for each item;

2) Once at btrfs_insert_empty_items() to sum the elements of the data
sizes array and compute the total data size;

3) And then once again at setup_items_for_insert(), where we do exactly
the same as what we do at btrfs_insert_empty_items(), to compute the
total data size.

That is not bad for small arrays, but when the arrays have hundreds of
elements, the time spent on looping is not negligible. For example when
doing batch inserts of delayed items for dir index items or when logging
a directory, it's common to have 200 to 260 dir index items in a single
batch when using a leaf size of 16K and using file names between 8 and 12
characters. For a 64K leaf size, multiply that by 4. Taking into account
that during directory logging or when flushing delayed dir index items we
can have many of those large batches, the time spent on the looping adds
up quickly.

It's also more important to avoid it at setup_items_for_insert(), since
we are holding a write lock on a leaf and, in some cases, on upper nodes
of the btree, which causes us to block other tasks that want to access
the leaf and nodes for longer than necessary.

So change the code so that setup_items_for_insert() and
btrfs_insert_empty_items() no longer compute the total data size, and
instead rely on the caller to supply it. This makes us loop over the
array only once, where we can both populate the data size array and
compute the total data size, taking advantage of spatial and temporal
locality. To make this more manageable, use a structure to contain
all the relevant details for a batch of items (keys array, data sizes
array, total data size, number of items), and use it as an argument
for btrfs_insert_empty_items() and setup_items_for_insert().

This patch is part of a small patchset that is comprised of the following
patches:

btrfs: loop only once over data sizes array when inserting an item batch
btrfs: unexport setup_items_for_insert()
btrfs: use single bulk copy operations when logging directories

This is patch 1/3 and performance results, and the specific tests, are
included in the changelog of patch 3/3.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: initialize test inodes location

I noticed that sometimes the module failed to load because the self
tests failed like this:

BTRFS: selftest: fs/btrfs/tests/inode-tests.c:963 miscount, wanted 1, got 0

This turned out to be because sometimes the btrfs ino would be the btree
inode number, and thus we'd skip calling the set extent delalloc bit
helper, and thus not adjust ->outstanding_extents.

Fix this by making sure we initialize test inodes with a valid inode
number so that we don't get random failures during self tests.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: fix missing delalloc new bit for new delalloc ranges

When doing a buffered write, through one of the write family syscalls, we
look for ranges which currently don't have allocated extents and set the
'delalloc new' bit on them, so that we can report a correct number of used
blocks to the stat(2) syscall until delalloc is flushed and ordered extents
complete.

However there are a few other places where we can do a buffered write
against a range that is mapped to a hole (no extent allocated) and where
we do not set the 'new delalloc' bit. Those places are:

- Doing a memory mapped write against a hole;

- Cloning an inline extent into a hole starting at file offset 0;

- Calling btrfs_cont_expand() when the i_size of the file is not aligned
to the sector size and is located in a hole. For example when cloning
to a destination offset beyond EOF.

So after such cases, until the corresponding delalloc range is flushed and
the respective ordered extents complete, we can report an incorrect number
of blocks used through the stat(2) syscall.

In some cases we can end up reporting 0 used blocks to stat(2), which is a
particular bad value to report as it may mislead tools to think a file is
completely sparse when its i_size is not zero, making them skip reading
any data, an undesired consequence for tools such as archivers and other
backup tools, as reported a long time ago in the following thread (and
other past threads):

https://lists.gnu.org/archive/html/bug-tar/2016-07/msg00001.html

Example reproducer:

$ cat reproducer.sh
#!/bin/bash

MNT=/mnt/sdi
DEV=/dev/sdi

mkfs.btrfs -f $DEV > /dev/null
# mkfs.xfs -f $DEV > /dev/null
# mkfs.ext4 -F $DEV > /dev/null
# mkfs.f2fs -f $DEV > /dev/null
mount $DEV $MNT

xfs_io -f -c "truncate 64K" \
-c "mmap -w 0 64K" \
-c "mwrite -S 0xab 0 64K" \
-c "munmap" \
$MNT/foo

blocks_used=$(stat -c %b $MNT/foo)
echo "blocks used: $blocks_used"

if [ $blocks_used -eq 0 ]; then
echo "ERROR: blocks used is 0"
fi

umount $DEV

$ ./reproducer.sh
blocks used: 0
ERROR: blocks used is 0

So move the logic that decides to set the 'delalloc bit' bit into the
function btrfs_set_extent_delalloc(), since that is what we use for all
those missing cases as well as for the cases that currently work well.

This change is also preparatory work for an upcoming patch that fixes
other problems related to tracking and reporting the number of bytes used
by an inode.

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>

btrfs: remove struct extent_io_ops

It's no longer used just remove the function and any related code which
was initialising it for inodes. No functional changes.

Removing 8 bytes from extent_io_tree in turn reduces size of other
structures where it is embedded, notably btrfs_inode where it reduces
size by 24 bytes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: sink total_data parameter in setup_items_for_insert

That parameter can easily be derived based on the "data_size" and "nr"
parameters exploit this fact to simply the function's signature. No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: eliminate total_size parameter from setup_items_for_insert

The value of this argument can be derived from the total_data as it's
simply the value of the data size + size of btrfs_items being touched.
Move the parameter calculation inside the function. This results in a
simpler interface and also a minor size reduction:

./scripts/bloat-o-meter ctree.original fs/btrfs/ctree.o
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-34 (-34)
Function old new delta
btrfs_duplicate_item 260 259 -1
setup_items_for_insert 1200 1190 -10
btrfs_insert_empty_items 177 154 -23

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: make btrfs_set_extent_delalloc take btrfs_inode

Preparation to make btrfs_dirty_pages take btrfs_inode as parameter.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: drop create parameter to btrfs_get_extent()

We only pass this as 1 from __extent_writepage_io(). The parameter
basically means "pretend I didn't pass in a page". This is silly since
we can simply not pass in the page. Get rid of the parameter from
btrfs_get_extent(), and since it's used as a get_extent_t callback,
remove it from get_extent_t and btree_get_extent(), neither of which
need it.

While we're here, let's document btrfs_get_extent().

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: stop clearing EXTENT_DIRTY in inode I/O tree

Since commit fee187d9d9dd ("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>

btrfs: Remove leftover of in-band dedupe

It's unlikely in-band dedupe is going to land so just remove any
leftovers - dedupe.h header as well as the 'dedupe' parameter to
btrfs_set_extent_delalloc.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: inode: Verify inode mode to avoid NULL pointer dereference

[BUG]
When accessing a file on a crafted image, btrfs can crash in block layer:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
PGD 136501067 P4D 136501067 PUD 124519067 PMD 0
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.0.0-rc8-default #252
RIP: 0010:end_bio_extent_readpage+0x144/0x700
Call Trace:
<IRQ>
blk_update_request+0x8f/0x350
blk_mq_end_request+0x1a/0x120
blk_done_softirq+0x99/0xc0
__do_softirq+0xc7/0x467
irq_exit+0xd1/0xe0
call_function_single_interrupt+0xf/0x20
</IRQ>
RIP: 0010:default_idle+0x1e/0x170

[CAUSE]
The crafted image has a tricky corruption, the INODE_ITEM has a
different type against its parent dir:

item 20 key (268 INODE_ITEM 0) itemoff 2808 itemsize 160
generation 13 transid 13 size 1048576 nbytes 1048576
block group 0 mode 121644 links 1 uid 0 gid 0 rdev 0
sequence 9 flags 0x0(none)

This mode number 0120000 means it's a symlink.

But the dir item think it's still a regular file:

item 8 key (264 DIR_INDEX 5) itemoff 3707 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4
item 40 key (264 DIR_ITEM 51821248) itemoff 1573 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4

For symlink, we don't set BTRFS_I(inode)->io_tree.ops and leave it
empty, as symlink is only designed to have inlined extent, all handled
by tree block read. Thus no need to trigger btrfs_submit_bio_hook() for
inline file extent.

However end_bio_extent_readpage() expects tree->ops populated, as it's
reading regular data extent. This causes NULL pointer dereference.

[FIX]
This patch fixes the problem in two ways:

- Verify inode mode against its dir item when looking up inode
So in btrfs_lookup_dentry() if we find inode mode mismatch with dir
item, we error out so that corrupted inode will not be accessed.

- Verify inode mode when getting extent mapping
Only regular file should have regular or preallocated extent.
If we found regular/preallocated file extent for symlink or
the rest, we error out before submitting the read bio.

With this fix that crafted image can be rejected gracefully:

BTRFS critical (device loop0): inode mode mismatch with dir: inode mode=0121644 btrfs type=7 dir type=1

Reported-by: Yoon Jungyeon <jungyeon@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202763
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: unify messages when tests start

- make the messages more visually consistent and use same format
"running ... test", any error or other warning can be easily spotted

- move some message to the test entry function

- add message to the inode tests

Example output:

[ 8.187391] Btrfs loaded, crc32c=crc32c-generic, assert=on, integrity-checker=on, ref-verify=on
[ 8.189476] BTRFS: selftest: sectorsize: 4096 nodesize: 4096
[ 8.190761] BTRFS: selftest: running btrfs free space cache tests
[ 8.192245] BTRFS: selftest: running extent only tests
[ 8.193573] BTRFS: selftest: running bitmap only tests
[ 8.194876] BTRFS: selftest: running bitmap and extent tests
[ 8.196166] BTRFS: selftest: running space stealing from bitmap to extent tests
[ 8.198026] BTRFS: selftest: running extent buffer operation tests
[ 8.199328] BTRFS: selftest: running btrfs_split_item tests
[ 8.200653] BTRFS: selftest: running extent I/O tests
[ 8.201808] BTRFS: selftest: running find delalloc tests
[ 8.320733] BTRFS: selftest: running extent buffer bitmap tests
[ 8.340795] BTRFS: selftest: running inode tests
[ 8.341766] BTRFS: selftest: running btrfs_get_extent tests
[ 8.342981] BTRFS: selftest: running hole first btrfs_get_extent test
[ 8.344342] BTRFS: selftest: running outstanding_extents tests
[ 8.345575] BTRFS: selftest: running qgroup tests
[ 8.346537] BTRFS: selftest: running qgroup add/remove tests
[ 8.347725] BTRFS: selftest: running qgroup multiple refs test
[ 8.354982] BTRFS: selftest: running free space tree tests
[ 8.372175] BTRFS: selftest: sectorsize: 4096 nodesize: 8192
[ 8.373539] BTRFS: selftest: running btrfs free space cache tests
[ 8.374989] BTRFS: selftest: running extent only tests
[ 8.376236] BTRFS: selftest: running bitmap only tests
[ 8.377483] BTRFS: selftest: running bitmap and extent tests
[ 8.378854] BTRFS: selftest: running space stealing from bitmap to extent tests
...

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: use standard error message after inode allocation failure

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: use standard error message after extent buffer allocation failure

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: use standard error message after root allocation failure

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: use standard error message after fs_info allocation failure

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Adjust loop in free_extent_buffer

The loop construct in free_extent_buffer was added in
242e18c7c1a8 ("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>

btrfs: tests: drop newline from test_msg strings

Now that test_err strings do not need the newline, remove them also from
the test_msg.

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: add helper for error messages and update them

The test failures are not clearly visible in the system log as they're
printed at INFO level. Add a new helper that is level ERROR. As this
touches almost all strings, I took the opportunity to unify them:

- decapitalize the first letter as there's a prefix and the text
continues after ":"
- glue strings split to more lines and un-indent so they fit to 80
columns
- use %llu instead of %Lu
- drop \n from the modified messages (test_msg is left untouched)

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: replace GPL boilerplate by SPDX -- sources

Remove GPL boilerplate text (long, short, one-line) and keep the rest,
ie. personal, company or original source copyright statements. Add the
SPDX header.

Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Remove redundant FLAG_VACANCY

Commit 9036c10208e1 ("Btrfs: update hole handling v2") added the
FLAG_VACANCY to denote holes, however there was already a consistent way
of flagging extents which represent hole - ->block_start =
EXTENT_MAP_HOLE. And also the only place where this flag is checked is
in the fiemap code, but the block_start value is also checked and every
other place in the filesystem detects holes by using block_start
value's. So remove the extra flag. This survived a full xfstest run.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: sink gfp parameter to clear_extent_bit

All callers use GFP_NOFS, we don't have to pass it as an argument. The
built-in tests pass GFP_KERNEL, but they run only at module load time
and NOFS works there as well.

Signed-off-by: David Sterba <dsterba@suse.com>

Btrfs: fix reported number of inode blocks after buffered append writes

The patch from commit a7e3b975a0f9 ("Btrfs: fix reported number of inode
blocks") introduced a regression where if we do a buffered write starting
at position equal to or greater than the file's size and then stat(2) the
file before writeback is triggered, the number of used blocks does not
change (unless there's a prealloc/unwritten extent). Example:

$ xfs_io -f -c "pwrite -S 0xab 0 64K" foobar
$ du -h foobar
0 foobar
$ sync
$ du -h foobar
64K foobar

The first version of that patch didn't had this regression and the second
version, which was the one committed, was made only to address some
performance regression detected by the intel test robots using fs_mark.

This fixes the regression by setting the new delaloc bit in the range, and
doing it at btrfs_dirty_pages() while setting the regular dealloc bit as
well, so that this way we set both bits at once avoiding navigation of the
inode's io tree twice. Doing it at btrfs_dirty_pages() is also the most
meaninful place, as we should set the new dellaloc bit when if we set the
delalloc bit, which happens only if we copied bytes into the pages at
__btrfs_buffered_write().

This was making some of LTP's du tests fail, which can be quickly run
using a command line like the following:

$ ./runltp -q -p -l /ltp.log -f commands -s du -d /mnt

Fixes: a7e3b975a0f9 ("Btrfs: fix reported number of inode blocks")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Btrfs: rework outstanding_extents

Right now we do a lot of weird hoops around outstanding_extents in order
to keep the extent count consistent. This is because we logically
transfer the outstanding_extent count from the initial reservation
through the set_delalloc_bits. This makes it pretty difficult to get a
handle on how and when we need to mess with outstanding_extents.

Fix this by revamping the rules of how we deal with outstanding_extents.
Now instead everybody that is holding on to a delalloc extent is
required to increase the outstanding extents count for itself. This
means we'll have something like this

btrfs_delalloc_reserve_metadata - outstanding_extents = 1
btrfs_set_extent_delalloc - outstanding_extents = 2
btrfs_release_delalloc_extents - outstanding_extents = 1

for an initial file write. Now take the append write where we extend an
existing delalloc range but still under the maximum extent size

btrfs_delalloc_reserve_metadata - outstanding_extents = 2
btrfs_set_extent_delalloc
btrfs_set_bit_hook - outstanding_extents = 3
btrfs_merge_extent_hook - outstanding_extents = 2
btrfs_delalloc_release_extents - outstanding_extnets = 1

In order to make the ordered extent transition we of course must now
make ordered extents carry their own outstanding_extent reservation, so
for cow_file_range we end up with

btrfs_add_ordered_extent - outstanding_extents = 2
clear_extent_bit - outstanding_extents = 1
btrfs_remove_ordered_extent - outstanding_extents = 0

This makes all manipulations of outstanding_extents much more explicit.
Every successful call to btrfs_delalloc_reserve_metadata _must_ now be
combined with btrfs_release_delalloc_extents, even in the error case, as
that is the only function that actually modifies the
outstanding_extents counter.

The drawback to this is now we are much more likely to have transient
cases where outstanding_extents is much larger than it actually should
be. This could happen before as we manipulated the delalloc bits, but
now it happens basically at every write. This may put more pressure on
the ENOSPC flushing code, but I think making this code simpler is worth
the cost. I have another change coming to mitigate this side-effect
somewhat.

I also added trace points for the counter manipulation. These were used
by a bpf script I wrote to help track down leak issues.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Replace opencoded sizes with their symbolic constants

Currently btrfs' code uses a mix of opencoded sizes and defines from sizes.h.
Let's unifiy the code base to always use the symbolic constants. No functional
changes

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Make get_extent_t take btrfs_inode

In addition to changing the signature, this patch also switches
all the functions which are used as an argument to also take btrfs_inode.
Namely those are: btrfs_get_extent and btrfs_get_extent_filemap.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Make btrfs_drop_extent_cache take btrfs_inode

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: pull node/sector/stripe sizes out of root and into fs_info

We track the node sizes per-root, but they never vary from the values
in the superblock. This patch messes with the 80-column style a bit,
but subsequent patches to factor out root->fs_info into a convenience
variable fix it up again.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: extend btrfs_set_extent_delalloc and its friends to support in-band dedupe and subpage size patchset

Extend btrfs_set_extent_delalloc() and extent_clear_unlock_delalloc()
parameters for both in-band dedupe and subpage sector size patchset.

This should reduce conflict of both patchset and the effort to rebase
them.

Cc: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests, require fs_info for root

This allows the upcoming patchset to push nodesize and sectorsize into
fs_info.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Btrfs: self-tests: Support non-4k page size

self-tests code assumes 4k as the sectorsize and nodesize. This commit
fix hardcoded 4K. Enables the self-tests code to be executed on non-4k
page sized systems (e.g. ppc64).

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: fix string and comment grammatical issues and typos

Signed-off-by: Nicholas D Steeves <nsteeves@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: move btrfs_compression_type to compression.h

So that its better organized.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: tests: switch to GFP_KERNEL

There's no reason to do GFP_NOFS in tests, it's not data-heavy and
memory allocation failures would affect only developers or testers.

Signed-off-by: David Sterba <dsterba@suse.com>

Btrfs: use linux/sizes.h to represent constants

We use many constants to represent size and offset value. And to make
code readable we use '256 * 1024 * 1024' instead of '268435456' to
represent '256MB'. However we can make far more readable with 'SZ_256MB'
which is defined in the 'linux/sizes.h'.

So this patch replaces 'xxx * 1024 * 1024' kind of expression with
single 'SZ_xxxMB' if 'xxx' is a power of 2 then 'xxx * SZ_1M' if 'xxx' is
not a power of 2. And I haven't touched to '4096' & '8192' because it's
more intuitive than 'SZ_4KB' & 'SZ_8KB'.

Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Btrfs: add sanity test for outstanding_extents accounting

I introduced a regression wrt outstanding_extents accounting. These are tricky
areas that aren't easily covered by xfstests as we could change MAX_EXTENT_SIZE
at any time. So add sanity tests to cover the various conditions that are
tricky in order to make sure we don't introduce regressions in the future.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>

btrfs: unify extent buffer allocation api

Make the extent buffer allocation interface consistent. Cloned eb will
set a valid fs_info. For dummy eb, we can drop the length parameter and
set it from fs_info.

The built-in sanity checks may pass a NULL fs_info that's queried for
nodesize, but we know it's 4096.

Signed-off-by: David Sterba <dsterba@suse.cz>

Btrfs: add sanity tests for new qgroup accounting code

This exercises the various parts of the new qgroup accounting code. We do some
basic stuff and do some things with the shared refs to make sure all that code
works. I had to add a bunch of infrastructure because I needed to be able to
insert items into a fake tree without having to do all the hard work myself,
hopefully this will be usefull in the future. Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>

Btrfs: add a sanity test for a vacant extent at the front of a file

Btrfs_get_extent was not handling this case properly, add a test to make sure we
don't regress. Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

Btrfs: add tests for btrfs_get_extent

I'm going to be removing hole extents in the near future so I wanted to make a
sanity test for btrfs_get_extent to make sure I don't break anything in the
meantime. This patch just puts btrfs_get_extent through its paces by giving it
a completely unreasonable mapping to look at and make sure it is giving us back
maps that make sense. Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>