Calculate byte set size for data sample:
- calculate how many unique bytes have been in the sample
- for all bytes count > 0, check if we're still in the low count range
(~25%), such data are easily compressible, otherwise furhter analysis
is needed
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Walk over data sample and use memcmp to detect repeated patterns, like
zeros, but a bit more general.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
Copy sample data from the input data range to sample buffer then
calculate byte value count for that sample into bucket.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
Add basic defines and structures for data sampling.
Added macros:
- For future sampling algo
- For bucket size
Heuristic workspace:
- Add bucket for storing byte type counters
- Add sample array for storing partial copy of input data range
- Add counter for store current sample size to workspace
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes, comments updated ]
Signed-off-by: David Sterba <dsterba@suse.com>
Compression heuristic itself is not a compression type, as current
infrastructure provides workspaces for several compression types, it's
difficult to just add heuristic workspace.
Just refactor the code to support compression/heuristic workspaces with
maximum code sharing and minimum changes in it.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
This is bikeshedding, but it seems people are drastically more likely to
understand "zlib:9" as compression level rather than an algorithm
version compared to "zlib9".
Based on feedback on the mailinglist, the ":9" will be the only accepted
syntax. The level must be a single digit. Unrecognized format will
result to the default, for forward compatibility in a similar way the
compression algorithm specifier was relaxed in commit
a7164fa4e0 ("btrfs: prepare for extensions in compression
options").
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: David Sterba <dsterba@suse.com>
[ tighten the accepted format ]
Signed-off-by: David Sterba <dsterba@suse.com>
Preliminary support for setting compression level for zlib, the
following works:
$ mount -o compess=zlib # default
$ mount -o compess=zlib0 # same
$ mount -o compess=zlib9 # level 9, slower sync, less data
$ mount -o compess=zlib1 # level 1, faster sync, more data
$ mount -o remount,compress=zlib3 # level set by remount
The compress-force works the same as compress'. The level is visible in
the same format in /proc/mounts. Level set via file property does not
work yet.
Required patch: "btrfs: prepare for extensions in compression options"
Signed-off-by: David Sterba <dsterba@suse.com>
At few places we could use BLK_STS_OK and BLK_STS_NOSUPP.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Satoru Taekeuchi <satoru.takeuchi@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ dropped first hunk btrfs_endio_direct_read ]
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from David Sterba:
"We've collected a bunch of isolated fixes, for crashes, user-visible
behaviour or missing bits from other subsystem cleanups from the past.
The overall number is not small but I was not able to make it
significantly smaller. Most of the patches are supposed to go to
stable"
* 'for-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: log csums for all modified extents
Btrfs: fix unexpected result when dio reading corrupted blocks
btrfs: Report error on removing qgroup if del_qgroup_item fails
Btrfs: skip checksum when reading compressed data if some IO have failed
Btrfs: fix kernel oops while reading compressed data
Btrfs: use btrfs_op instead of bio_op in __btrfs_map_block
Btrfs: do not backup tree roots when fsync
btrfs: remove BTRFS_FS_QUOTA_DISABLING flag
btrfs: propagate error to btrfs_cmp_data_prepare caller
btrfs: prevent to set invalid default subvolid
Btrfs: send: fix error number for unknown inode types
btrfs: fix NULL pointer dereference from free_reloc_roots()
btrfs: finish ordered extent cleaning if no progress is found
btrfs: clear ordered flag on cleaning up ordered extents
Btrfs: fix incorrect {node,sector}size endianness from BTRFS_IOC_FS_INFO
Btrfs: do not reset bio->bi_ops while writing bio
Btrfs: use the new helper wbc_to_write_flags
Currently even if the underlying disk reports failure on IO,
compressed read endio still gets to verify checksum and reports it as
a checksum error.
In fact, if some IO have failed during reading a compressed data
extent , there's no way the checksum could match, therefore, we can
skip that in order to return error quickly to the upper layer.
Please note that we need to do this after recording the failed mirror
index so that read-repair in the upper layer's endio can work
properly.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-by: Paul Jones <paul@pauljones.id.au>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The kernel oops happens at
kernel BUG at fs/btrfs/extent_io.c:2104!
...
RIP: clean_io_failure+0x263/0x2a0 [btrfs]
It's showing that read-repair code is using an improper mirror index.
This is due to the fact that compression read's endio hasn't recorded
the failed mirror index in %cb->orig_bio.
With this, btrfs's read-repair can work properly on reading compressed
data.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Paul Jones <paul@pauljones.id.au>
Tested-by: Paul Jones <paul@pauljones.id.au>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull zstd support from Chris Mason:
"Nick Terrell's patch series to add zstd support to the kernel has been
floating around for a while. After talking with Dave Sterba, Herbert
and Phillip, we decided to send the whole thing in as one pull
request.
zstd is a big win in speed over zlib and in compression ratio over
lzo, and the compression team here at FB has gotten great results
using it in production. Nick will continue to update the kernel side
with new improvements from the open source zstd userland code.
Nick has a number of benchmarks for the main zstd code in his lib/zstd
commit:
I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB
of RAM. The VM is running on a MacBook Pro with a 3.1 GHz Intel
Core i7 processor, 16 GB of RAM, and a SSD. I benchmarked using
`silesia.tar` [3], which is 211,988,480 B large. Run the following
commands for the benchmark:
sudo modprobe zstd_compress_test
sudo mknod zstd_compress_test c 245 0
sudo cp silesia.tar zstd_compress_test
The time is reported by the time of the userland `cp`.
The MB/s is computed with
1,536,217,008 B / time(buffer size, hash)
which includes the time to copy from userland.
The Adjusted MB/s is computed with
1,536,217,088 B / (time(buffer size, hash) - time(buffer size, none)).
The memory reported is the amount of memory the compressor
requests.
| Method | Size (B) | Time (s) | Ratio | MB/s | Adj MB/s | Mem (MB) |
|----------|----------|----------|-------|---------|----------|----------|
| none | 11988480 | 0.100 | 1 | 2119.88 | - | - |
| zstd -1 | 73645762 | 1.044 | 2.878 | 203.05 | 224.56 | 1.23 |
| zstd -3 | 66988878 | 1.761 | 3.165 | 120.38 | 127.63 | 2.47 |
| zstd -5 | 65001259 | 2.563 | 3.261 | 82.71 | 86.07 | 2.86 |
| zstd -10 | 60165346 | 13.242 | 3.523 | 16.01 | 16.13 | 13.22 |
| zstd -15 | 58009756 | 47.601 | 3.654 | 4.45 | 4.46 | 21.61 |
| zstd -19 | 54014593 | 102.835 | 3.925 | 2.06 | 2.06 | 60.15 |
| zlib -1 | 77260026 | 2.895 | 2.744 | 73.23 | 75.85 | 0.27 |
| zlib -3 | 72972206 | 4.116 | 2.905 | 51.50 | 52.79 | 0.27 |
| zlib -6 | 68190360 | 9.633 | 3.109 | 22.01 | 22.24 | 0.27 |
| zlib -9 | 67613382 | 22.554 | 3.135 | 9.40 | 9.44 | 0.27 |
I benchmarked zstd decompression using the same method on the same
machine. The benchmark file is located in the upstream zstd repo
under `contrib/linux-kernel/zstd_decompress_test.c` [4]. The
memory reported is the amount of memory required to decompress
data compressed with the given compression level. If you know the
maximum size of your input, you can reduce the memory usage of
decompression irrespective of the compression level.
| Method | Time (s) | MB/s | Adjusted MB/s | Memory (MB) |
|----------|----------|---------|---------------|-------------|
| none | 0.025 | 8479.54 | - | - |
| zstd -1 | 0.358 | 592.15 | 636.60 | 0.84 |
| zstd -3 | 0.396 | 535.32 | 571.40 | 1.46 |
| zstd -5 | 0.396 | 535.32 | 571.40 | 1.46 |
| zstd -10 | 0.374 | 566.81 | 607.42 | 2.51 |
| zstd -15 | 0.379 | 559.34 | 598.84 | 4.61 |
| zstd -19 | 0.412 | 514.54 | 547.77 | 8.80 |
| zlib -1 | 0.940 | 225.52 | 231.68 | 0.04 |
| zlib -3 | 0.883 | 240.08 | 247.07 | 0.04 |
| zlib -6 | 0.844 | 251.17 | 258.84 | 0.04 |
| zlib -9 | 0.837 | 253.27 | 287.64 | 0.04 |
I ran a long series of tests and benchmarks on the btrfs side and the
gains are very similar to the core benchmarks Nick ran"
* 'zstd-minimal' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
squashfs: Add zstd support
btrfs: Add zstd support
lib: Add zstd modules
lib: Add xxhash module
Add skeleton code for compresison heuristics. Now it iterates over all
the pages, but in the end always says "yes, compress please", ie it does
not change the current behaviour.
In the future we're going to add various heuristics to analyze the data.
This patch can be used as a baseline for measuring if the effectivness
and performance.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhanced changelog, modified comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
find_workspace() allocates up to num_online_cpus() + 1 workspaces.
free_workspace() will only keep num_online_cpus() workspaces. When
(de)compressing we will allocate num_online_cpus() + 1 workspaces, then
free one, and repeat. Instead, we can just keep num_online_cpus() + 1
workspaces around, and never have to allocate/free another workspace in the
common case.
I tested on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM. I mounted a
BtrFS partition with -o compress-force={lzo,zlib,zstd} and logged whenever
a workspace was allocated of freed. Then I copied vmlinux (527 MB) to the
partition. Before the patch, during the copy it would allocate and free 5-6
workspaces. After, it only allocated the initial 3. This held true for lzo,
zlib, and zstd. The time it took to execute cp vmlinux /mnt/btrfs && sync
dropped from 1.70s to 1.44s with lzo compression, and from 2.04s to 1.80s
for zstd compression.
Signed-off-by: Nick Terrell <terrelln@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add zstd compression and decompression support to BtrFS. zstd at its
fastest level compresses almost as well as zlib, while offering much
faster compression and decompression, approaching lzo speeds.
I benchmarked btrfs with zstd compression against no compression, lzo
compression, and zlib compression. I benchmarked two scenarios. Copying
a set of files to btrfs, and then reading the files. Copying a tarball
to btrfs, extracting it to btrfs, and then reading the extracted files.
After every operation, I call `sync` and include the sync time.
Between every pair of operations I unmount and remount the filesystem
to avoid caching. The benchmark files can be found in the upstream
zstd source repository under
`contrib/linux-kernel/{btrfs-benchmark.sh,btrfs-extract-benchmark.sh}`
[1] [2].
I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM.
The VM is running on a MacBook Pro with a 3.1 GHz Intel Core i7 processor,
16 GB of RAM, and a SSD.
The first compression benchmark is copying 10 copies of the unzipped
Silesia corpus [3] into a BtrFS filesystem mounted with
`-o compress-force=Method`. The decompression benchmark times how long
it takes to `tar` all 10 copies into `/dev/null`. The compression ratio is
measured by comparing the output of `df` and `du`. See the benchmark file
[1] for details. I benchmarked multiple zstd compression levels, although
the patch uses zstd level 1.
| Method | Ratio | Compression MB/s | Decompression speed |
|---------|-------|------------------|---------------------|
| None | 0.99 | 504 | 686 |
| lzo | 1.66 | 398 | 442 |
| zlib | 2.58 | 65 | 241 |
| zstd 1 | 2.57 | 260 | 383 |
| zstd 3 | 2.71 | 174 | 408 |
| zstd 6 | 2.87 | 70 | 398 |
| zstd 9 | 2.92 | 43 | 406 |
| zstd 12 | 2.93 | 21 | 408 |
| zstd 15 | 3.01 | 11 | 354 |
The next benchmark first copies `linux-4.11.6.tar` [4] to btrfs. Then it
measures the compression ratio, extracts the tar, and deletes the tar.
Then it measures the compression ratio again, and `tar`s the extracted
files into `/dev/null`. See the benchmark file [2] for details.
| Method | Tar Ratio | Extract Ratio | Copy (s) | Extract (s)| Read (s) |
|--------|-----------|---------------|----------|------------|----------|
| None | 0.97 | 0.78 | 0.981 | 5.501 | 8.807 |
| lzo | 2.06 | 1.38 | 1.631 | 8.458 | 8.585 |
| zlib | 3.40 | 1.86 | 7.750 | 21.544 | 11.744 |
| zstd 1 | 3.57 | 1.85 | 2.579 | 11.479 | 9.389 |
[1] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-benchmark.sh
[2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-extract-benchmark.sh
[3] http://sun.aei.polsl.pl/~sdeor/index.php?page=silesia
[4] https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.11.6.tar.xz
zstd source repository: https://github.com/facebook/zstd
Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs fixes from David Sterba:
"We've identified and fixed a silent corruption (introduced by code in
the first pull), a fixup after the blk_status_t merge and two fixes to
incremental send that Filipe has been hunting for some time"
* 'for-4.13-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix unexpected return value of bio_readpage_error
btrfs: btrfs_create_repair_bio never fails, skip error handling
btrfs: cloned bios must not be iterated by bio_for_each_segment_all
Btrfs: fix write corruption due to bio cloning on raid5/6
Btrfs: incremental send, fix invalid memory access
Btrfs: incremental send, fix invalid path for link commands
We've started using cloned bios more in 4.13, there are some specifics
regarding the iteration. Filipe found [1] that the raid56 iterated a
cloned bio using bio_for_each_segment_all, which is incorrect. The
cloned bios have wrong bi_vcnt and this could lead to silent
corruptions. This patch adds assertions to all remaining
bio_for_each_segment_all cases.
[1] https://patchwork.kernel.org/patch/9838535/
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs updates from David Sterba:
"The core updates improve error handling (mostly related to bios), with
the usual incremental work on the GFP_NOFS (mis)use removal,
refactoring or cleanups. Except the two top patches, all have been in
for-next for an extensive amount of time.
User visible changes:
- statx support
- quota override tunable
- improved compression thresholds
- obsoleted mount option alloc_start
Core updates:
- bio-related updates:
- faster bio cloning
- no allocation failures
- preallocated flush bios
- more kvzalloc use, memalloc_nofs protections, GFP_NOFS updates
- prep work for btree_inode removal
- dir-item validation
- qgoup fixes and updates
- cleanups:
- removed unused struct members, unused code, refactoring
- argument refactoring (fs_info/root, caller -> callee sink)
- SEARCH_TREE ioctl docs"
* 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (115 commits)
btrfs: Remove false alert when fiemap range is smaller than on-disk extent
btrfs: Don't clear SGID when inheriting ACLs
btrfs: fix integer overflow in calc_reclaim_items_nr
btrfs: scrub: fix target device intialization while setting up scrub context
btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges
btrfs: qgroup: Introduce extent changeset for qgroup reserve functions
btrfs: qgroup: Fix qgroup reserved space underflow caused by buffered write and quotas being enabled
btrfs: qgroup: Return actually freed bytes for qgroup release or free data
btrfs: qgroup: Cleanup btrfs_qgroup_prepare_account_extents function
btrfs: qgroup: Add quick exit for non-fs extents
Btrfs: rework delayed ref total_bytes_pinned accounting
Btrfs: return old and new total ref mods when adding delayed refs
Btrfs: always account pinned bytes when dropping a tree block ref
Btrfs: update total_bytes_pinned when pinning down extents
Btrfs: make BUG_ON() in add_pinned_bytes() an ASSERT()
Btrfs: make add_pinned_bytes() take an s64 num_bytes instead of u64
btrfs: fix validation of XATTR_ITEM dir items
btrfs: Verify dir_item in iterate_object_props
btrfs: Check name_len before in btrfs_del_root_ref
btrfs: Check name_len before reading btrfs_get_name
...
This function is supposed to return blk_status_t error codes now but
there was a stray -ENOMEM left behind.
Fixes: 4e4cbee93d ("block: switch bios to blk_status_t")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Most callers of btrfs_bio_alloc convert from bytes to sectors. Hide that
in the helper and simplify the logic in the callsers.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
compressed_bio_alloc is now a trivial wrapper around btrfs_bio_alloc, no
point keeping it. The error handling can be simplified, as we know
btrfs_bio_alloc will never fail.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers pass gfp_flags=GFP_NOFS and nr_vecs=BIO_MAX_PAGES.
submit_extent_page adds __GFP_HIGH that does not make a difference in
our case as it allows access to memory reserves but otherwise does not
change the constraints.
Signed-off-by: David Sterba <dsterba@suse.com>
The workspaces are preallocated at the beginning where we can safely use
GFP_KERNEL, but in some cases the find_workspace might reach the
allocation again, now in a more restricted context when the bios or
pages are being compressed.
To avoid potential lockup when alloc_workspace -> vmalloc would silently
use the GFP_KERNEL, add the memalloc_nofs helpers around the critical
call site.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
struct compressed_bio pointer can be used instead.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of sending each argument of struct compressed_bio, send
the compressed_bio itself.
Also by having struct compressed_bio in btrfs_decompress_bio()
it would help tracing.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of max_out can be calculated from the parameters passed to the
compressors, which is number of pages and the page size, and we don't
have to needlessly pass it around.
Signed-off-by: David Sterba <dsterba@suse.com>
The parameter saying how many pages can be allocated at maximum can be
merged with the output page counter, to save some stack space. The
compression implementation will sink the parameter to a local variable
so everything works as before.
The nr_pages variables can also be simply merged in compress_file_range
into one.
Signed-off-by: David Sterba <dsterba@suse.com>
The length parameter is basically duplicated for input and output in the
top level caller of the compress_pages chain. We can simply use one
variable for that and reduce stack consumption. The compression
implementation will sink the parameter to a local variable so everything
works as before.
Signed-off-by: David Sterba <dsterba@suse.com>
The original csum error message only outputs inode number, offset, check
sum and expected check sum.
However no root objectid is outputted, which sometimes makes debugging
quite painful under multi-subvolume case (including relocation).
Also the checksum output is decimal, which seldom makes sense for
users/developers and is hard to read in most time.
This patch will add root objectid, which will be %lld for rootid larger
than LAST_FREE_OBJECTID, and hex csum output for better readability.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_ino takes a struct inode and this causes a lot of
internal btrfs functions which consume this ino to take a VFS inode,
rather than btrfs' own struct btrfs_inode. In order to fix this "leak"
of VFS structs into the internals of btrfs first it's necessary to
eliminate all uses of struct inode for the purpose of inode. This patch
does that by using BTRFS_I to convert an inode to btrfs_inode. With
this problem eliminated subsequent patches will start eliminating the
passing of struct inode altogether, eventually resulting in a lot cleaner
code.
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
[ fix btrfs_get_extent tracepoint prototype ]
Signed-off-by: David Sterba <dsterba@suse.com>
If btrfs_decompress_buf2page() is handed a bio with its page in the
middle of the working buffer, then we adjust the offset into the working
buffer. After we copy into the bio, we advance the iterator by the
number of bytes we copied. Then, we have some logic to handle the case
of discontiguous pages and adjust the offset into the working buffer
again. However, if we didn't advance the bio to a new page, we may enter
this case in error, essentially repeating the adjustment that we already
made when we entered the function. The end result is bogus data in the
bio.
Previously, we only checked for this case when we advanced to a new
page, but the conversion to bio iterators changed that. This restores
the old, correct behavior.
A case I saw when testing with zlib was:
buf_start = 42769
total_out = 46865
working_bytes = total_out - buf_start = 4096
start_byte = 45056
The condition (total_out > start_byte && buf_start < start_byte) is
true, so we adjust the offset:
buf_offset = start_byte - buf_start = 2287
working_bytes -= buf_offset = 1809
current_buf_start = buf_start = 42769
Then, we copy
bytes = min(bvec.bv_len, PAGE_SIZE - buf_offset, working_bytes) = 1809
buf_offset += bytes = 4096
working_bytes -= bytes = 0
current_buf_start += bytes = 44578
After bio_advance(), we are still in the same page, so start_byte is the
same. Then, we check (total_out > start_byte && current_buf_start < start_byte),
which is true! So, we adjust the values again:
buf_offset = start_byte - buf_start = 2287
working_bytes = total_out - start_byte = 1809
current_buf_start = buf_start + buf_offset = 45056
But note that working_bytes was already zero before this, so we should
have stopped copying.
Fixes: 974b1adc3b ("btrfs: use bio iterators for the decompression handlers")
Reported-by: Pat Erley <pat-lkml@erley.org>
Reviewed-by: Chris Mason <clm@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Tested-by: Liu Bo <bo.li.liu@oracle.com>
There are loads of functions in btrfs that accept a root parameter
but only use it to obtain an fs_info pointer. Let's convert those to
just accept an fs_info pointer directly.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In routines where someptr->fs_info is referenced multiple times, we
introduce a convenience variable. This makes the code considerably
more readable.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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>
Use the bvec offset and len members to prepare for multipage bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of using bi_vcnt to calculate it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pass the full bio to the decompression routines and use bio iterators
to iterate over the data in the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
csum member of struct btrfs_super_block has array type of u8. It makes
sense that function btrfs_csum_final should be also declared to accept
u8 *. I changed the declaration of method void btrfs_csum_final(u32 crc,
char *result); to void btrfs_csum_final(u32 crc, u8 *result);
Signed-off-by: Domagoj Tršan <domagoj.trsan@gmail.com>
[ changed cast to u8 at several call sites ]
Signed-off-by: David Sterba <dsterba@suse.com>
For many printks, we want to know which file system issued the message.
This patch converts most pr_* calls to use the btrfs_* versions instead.
In some cases, this means adding plumbing to allow call sites access to
an fs_info pointer.
fs/btrfs/check-integrity.c is left alone for another day.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch converts printk(KERN_* style messages to use the pr_* versions.
One side effect is that anything that was KERN_DEBUG is now automatically
a dynamic debug message.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull more btrfs updates from Chris Mason:
"This is part two of my btrfs pull, which is some cleanups and a batch
of fixes.
Most of the code here is from Jeff Mahoney, making the pointers we
pass around internally more consistent and less confusing overall. I
noticed a small problem right before I sent this out yesterday, so I
fixed it up and re-tested overnight"
* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (40 commits)
Btrfs: fix __MAX_CSUM_ITEMS
btrfs: btrfs_abort_transaction, drop root parameter
btrfs: add btrfs_trans_handle->fs_info pointer
btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction
btrfs: convert nodesize macros to static inlines
btrfs: introduce BTRFS_MAX_ITEM_SIZE
btrfs: cleanup, remove prototype for btrfs_find_root_ref
btrfs: copy_to_sk drop unused root parameter
btrfs: simpilify btrfs_subvol_inherit_props
btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root
btrfs: tests, require fs_info for root
btrfs: tests, move initialization into tests/
btrfs: btrfs_test_opt and friends should take a btrfs_fs_info
btrfs: prefix fsid to all trace events
btrfs: plumb fs_info into btrfs_work
btrfs: remove obsolete part of comment in statfs
btrfs: hide test-only member under ifdef
btrfs: Ratelimit "no csum found" info message
btrfs: Add ratelimit to btrfs printing
Btrfs: fix unexpected balance crash due to BUG_ON
...
This is similar to btrfs_submit_compressed_read(), if we fail after
bio is allocated, then we can use bio_endio() and errors are saved
in bio->bi_error. But please note that we don't return errors to
its caller because the caller assumes it won't call endio to cleanup
on error.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The bio REQ_OP and bi_rw rq_flag_bits are now always setup, so there is
no need to pass around the rq_flag_bits bits too. btrfs users should
should access the bio insead.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This should be the easier cases to convert btrfs to
bio_set_op_attrs/bio_op.
They are mostly just cut and replace type of changes.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
