Commit Graph

233 Commits

Author SHA1 Message Date
Linus Torvalds 7a7fd0de4a Merge branch 'kmap-conversion-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull kmap conversion updates from David Sterba:
 "This contains changes regarding kmap API use and eg conversion from
  kmap_atomic to kmap_local_page.

  The API belongs to memory management but to save cross-tree
  dependency headaches we've agreed to take it through the btrfs tree
  because there are some trivial conversions possible, while the rest
  will need some time and getting the easy cases out of the way would be
  convenient.

  The changes can be grouped:

   - function exports, new helpers

   - new VM_BUG_ON for additional verification; it's been discussed if
     it should be VM_BUG_ON or BUG_ON, the former was chosen due to
     performance reasons

   - code replaced by relevant helpers"

[ This is an updated version of a request that originally came in during
  the merge window, but I asked for some updates:

    https://lore.kernel.org/lkml/cover.1614090658.git.dsterba@suse.com/

  which is why this got merge after the merge window closed.  - Linus ]

* 'kmap-conversion-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: use copy_highpage() instead of 2 kmaps()
  btrfs: use memcpy_[to|from]_page() and kmap_local_page()
  mm/highmem: Add VM_BUG_ON() to mem*_page() calls
  mm/highmem: Introduce memcpy_page(), memmove_page(), and memset_page()
  mm/highmem: Convert memcpy_[to|from]_page() to kmap_local_page()
  mm/highmem: Lift memcpy_[to|from]_page to core
2021-03-01 11:24:18 -08:00
Ira Weiny 3590ec5899 btrfs: use memcpy_[to|from]_page() and kmap_local_page()
There are many places where the pattern kmap/memcpy/kunmap occurs.

This pattern was lifted to the core common functions
memcpy_[to|from]_page().

Use these new functions to reduce the code, eliminate direct uses of
kmap, and leverage the new core functions use of kmap_local_page().

Also, there is 1 place where a kmap/memcpy is followed by an
optional memset.  Here we leave the kmap open coded to avoid remapping
the page but use kmap_local_page() directly.

Development of this patch was aided by the coccinelle script:

// <smpl>
// SPDX-License-Identifier: GPL-2.0-only
// Find kmap/memcpy/kunmap pattern and replace with memcpy*page calls
//
// NOTE: Offsets and other expressions may be more complex than what the script
// will automatically generate.  Therefore a catchall rule is provided to find
// the pattern which then must be evaluated by hand.
//
// Confidence: Low
// Copyright: (C) 2021 Intel Corporation
// URL: http://coccinelle.lip6.fr/
// Comments:
// Options:

//
// simple memcpy version
//
@ memcpy_rule1 @
expression page, T, F, B, Off;
identifier ptr;
type VP;
@@

(
-VP ptr = kmap(page);
|
-ptr = kmap(page);
|
-VP ptr = kmap_atomic(page);
|
-ptr = kmap_atomic(page);
)
<+...
(
-memcpy(ptr + Off, F, B);
+memcpy_to_page(page, Off, F, B);
|
-memcpy(ptr, F, B);
+memcpy_to_page(page, 0, F, B);
|
-memcpy(T, ptr + Off, B);
+memcpy_from_page(T, page, Off, B);
|
-memcpy(T, ptr, B);
+memcpy_from_page(T, page, 0, B);
)
...+>
(
-kunmap(page);
|
-kunmap_atomic(ptr);
)

// Remove any pointers left unused
@
depends on memcpy_rule1
@
identifier memcpy_rule1.ptr;
type VP, VP1;
@@

-VP ptr;
	... when != ptr;
? VP1 ptr;

//
// Some callers kmap without a temp pointer
//
@ memcpy_rule2 @
expression page, T, Off, F, B;
@@

<+...
(
-memcpy(kmap(page) + Off, F, B);
+memcpy_to_page(page, Off, F, B);
|
-memcpy(kmap(page), F, B);
+memcpy_to_page(page, 0, F, B);
|
-memcpy(T, kmap(page) + Off, B);
+memcpy_from_page(T, page, Off, B);
|
-memcpy(T, kmap(page), B);
+memcpy_from_page(T, page, 0, B);
)
...+>
-kunmap(page);
// No need for the ptr variable removal

//
// Catch all
//
@ memcpy_rule3 @
expression page;
expression GenTo, GenFrom, GenSize;
identifier ptr;
type VP;
@@

(
-VP ptr = kmap(page);
|
-ptr = kmap(page);
|
-VP ptr = kmap_atomic(page);
|
-ptr = kmap_atomic(page);
)
<+...
(
//
// Some call sites have complex expressions within the memcpy
// match a catch all to be evaluated by hand.
//
-memcpy(GenTo, GenFrom, GenSize);
+memcpy_to_pageExtra(page, GenTo, GenFrom, GenSize);
+memcpy_from_pageExtra(GenTo, page, GenFrom, GenSize);
)
...+>
(
-kunmap(page);
|
-kunmap_atomic(ptr);
)

// Remove any pointers left unused
@
depends on memcpy_rule3
@
identifier memcpy_rule3.ptr;
type VP, VP1;
@@

-VP ptr;
	... when != ptr;
? VP1 ptr;

// <smpl>

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-26 12:45:15 +01:00
Qu Wenruo 04d4ba4c90 btrfs: make check_compressed_csum() to be subpage compatible
Currently check_compressed_csum() completely relies on sectorsize ==
PAGE_SIZE to do checksum verification for compressed extents.

To make it subpage compatible, this patch will:
- Do extra calculation for the csum range
  Since we have multiple sectors inside a page, we need to only hash
  the range we want, not the full page anymore.

- Do sector-by-sector hash inside the page

With this patch and previous conversion on
btrfs_submit_compressed_read(), now we can read subpage compressed
extents properly, and do proper csum verification.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-22 17:15:27 +01:00
Qu Wenruo be6a13613f btrfs: make btrfs_submit_compressed_read() subpage compatible
For compressed read, we always submit page read using page size.  This
doesn't work well with subpage, as for subpage one page can contain
several sectors.  Such submission will read range out of what we want,
and cause problems.

Thankfully to make it subpage compatible, we only need to change how the
last page of the compressed extent is read.

Instead of always adding a full page to the compressed read bio, if we're
at the last page, calculate the size using compressed length, so that we
only add part of the range into the compressed read bio.

Since we are here, also change the PAGE_SIZE used in
lookup_extent_mapping() to sectorsize.
This modification won't cause any functional change, as
lookup_extent_mapping() can handle the case where the search range is
larger than found extent range.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-22 17:15:25 +01:00
Qu Wenruo 32443de338 btrfs: introduce btrfs_subpage for data inodes
To support subpage sector size, data also need extra info to make sure
which sectors in a page are uptodate/dirty/...

This patch will make pages for data inodes get btrfs_subpage structure
attached, and detached when the page is freed.

This patch also slightly changes the timing when
set_page_extent_mapped() is called to make sure:

- We have page->mapping set
  page->mapping->host is used to grab btrfs_fs_info, thus we can only
  call this function after page is mapped to an inode.

  One call site attaches pages to inode manually, thus we have to modify
  the timing of set_page_extent_mapped() a bit.

- As soon as possible, before other operations
  Since memory allocation can fail, we have to do extra error handling.
  Calling set_page_extent_mapped() as soon as possible can simply the
  error handling for several call sites.

The idea is pretty much the same as iomap_page, but with more bitmaps
for btrfs specific cases.

Currently the plan is to switch iomap if iomap can provide sector
aligned write back (only write back dirty sectors, but not the full
page, data balance require this feature).

So we will stick to btrfs specific bitmap for now.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-08 22:59:03 +01:00
Qu Wenruo 6275193ef1 btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs
Refactor btrfs_lookup_bio_sums() by:

- Remove the @file_offset parameter
  There are two factors making the @file_offset parameter useless:

  * For csum lookup in csum tree, file offset makes no sense
    We only need disk_bytenr, which is unrelated to file_offset

  * page_offset (file offset) of each bvec is not contiguous.
    Pages can be added to the same bio as long as their on-disk bytenr
    is contiguous, meaning we could have pages at different file offsets
    in the same bio.

  Thus passing file_offset makes no sense any more.
  The only user of file_offset is for data reloc inode, we will use
  a new function, search_file_offset_in_bio(), to handle it.

- Extract the csum tree lookup into search_csum_tree()
  The new function will handle the csum search in csum tree.
  The return value is the same as btrfs_find_ordered_sum(), returning
  the number of found sectors which have checksum.

- Change how we do the main loop
  The only needed info from bio is:
  * the on-disk bytenr
  * the length

  After extracting the above info, we can do the search without bio
  at all, which makes the main loop much simpler:

	for (cur_disk_bytenr = orig_disk_bytenr;
	     cur_disk_bytenr < orig_disk_bytenr + orig_len;
	     cur_disk_bytenr += count * sectorsize) {

		/* Lookup csum tree */
		count = search_csum_tree(fs_info, path, cur_disk_bytenr,
					 search_len, csum_dst);
		if (!count) {
			/* Csum hole handling */
		}
	}

- Use single variable as the source to calculate all other offsets
  Instead of all different type of variables, we use only one main
  variable, cur_disk_bytenr, which represents the current disk bytenr.

  All involved values can be calculated from that variable, and
  all those variable will only be visible in the inner loop.

The above refactoring makes btrfs_lookup_bio_sums() way more robust than
it used to be, especially related to the file offset lookup.  Now
file_offset lookup is only related to data reloc inode, otherwise we
don't need to bother file_offset at all.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09 19:16:11 +01:00
David Sterba 1201b58b67 btrfs: drop casts of bio bi_sector
Since commit 72deb455b5 ("block: remove CONFIG_LBDAF") (5.2) the
sector_t type is u64 on all arches and configs so we don't need to
typecast it.  It used to be unsigned long and the result of sector size
shifts were not guaranteed to fit in the type.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09 19:16:05 +01:00
David Sterba 713cebfb98 btrfs: remove unnecessary local variables for checksum size
Remove local variable that is then used just once and replace it with
fs_info::csum_size.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:00 +01:00
David Sterba 223486c27b btrfs: switch cached fs_info::csum_size from u16 to u32
The fs_info value is 32bit, switch also the local u16 variables. This
leads to a better assembly code generated due to movzwl.

This simple change will shave some bytes on x86_64 and release config:

   text    data     bss     dec     hex filename
1090000   17980   14912 1122892  11224c pre/btrfs.ko
1089794   17980   14912 1122686  11217e post/btrfs.ko

DELTA: -206

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:59 +01:00
David Sterba 55fc29bed8 btrfs: use cached value of fs_info::csum_size everywhere
btrfs_get_16 shows up in the system performance profiles (helper to read
16bit values from on-disk structures). This is partially because of the
checksum size that's frequently read along with data reads/writes, other
u16 uses are from item size or directory entries.

Replace all calls to btrfs_super_csum_size by the cached value from
fs_info.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:59 +01:00
Josef Bacik 42437a6386 btrfs: introduce mount option rescue=ignorebadroots
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system.  This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data.  Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:41 +01:00
Josef Bacik 334c16d82c btrfs: push the NODATASUM check into btrfs_lookup_bio_sums
When we move to being able to handle NULL csum_roots it'll be cleaner to
just check in btrfs_lookup_bio_sums instead of at all of the caller
locations, so push the NODATASUM check into it as well so it's unified.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@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>
2020-12-08 15:53:39 +01:00
David Sterba cb4c919830 btrfs: compression: move declarations to header
The declarations of compression algorithm callbacks are defined in the
.c file as they're used from there. Compiler warns that there are no
declarations for public functions when compiling lzo.c/zlib.c/zstd.c.
Fix that by moving the declarations to the header as it's the common
place for all of them.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:06:55 +02:00
Nikolay Borisov 93c4c033ec btrfs: remove fail label in check_compressed_csum
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:42 +02:00
Nikolay Borisov 5a9472fe7f btrfs: increment corrupt device counter during compressed read
If a compressed read fails due to checksum error only a line is printed
to dmesg, device corrupt counter is not modified.

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>
2020-07-27 12:55:40 +02:00
Nikolay Borisov 26056eab4b btrfs: remove needless ASSERT check of orig_bio in end_compressed_bio_read
compressed_bio::orig_bio is always set in btrfs_submit_compressed_read
before any bio submission is performed. Since that function is always
called with a valid bio it renders the ASSERT unnecessary.

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>
2020-07-27 12:55:40 +02:00
Nikolay Borisov c7ee1819dc btrfs: make btrfs_submit_compressed_write take btrfs_inode
Majority of its uses are for btrfs_inode so take it as an argument
directly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:31 +02:00
Nikolay Borisov bd242a08a6 btrfs: make btrfs_csum_one_bio takae btrfs_inode
Will enable converting btrfs_submit_compressed_write to btrfs_inode more
easily.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:26 +02:00
Anand Jain adbab6420c btrfs: unexport btrfs_compress_set_level()
btrfs_compress_set_level() can be static function in the file
compression.c.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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>
2020-05-25 11:25:37 +02:00
Eric Biggers fd08001f17 btrfs: use crypto_shash_digest() instead of open coding
Use crypto_shash_digest() instead of crypto_shash_init() +
crypto_shash_update() + crypto_shash_final().  This is more efficient.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-05-25 11:25:27 +02:00
Mikhail Zaslonko 3fd396afc0 btrfs: use larger zlib buffer for s390 hardware compression
In order to benefit from s390 zlib hardware compression support,
increase the btrfs zlib workspace buffer size from 1 to 4 pages (if s390
zlib hardware support is enabled on the machine).

This brings up to 60% better performance in hardware on s390 compared to
the PAGE_SIZE buffer and much more compared to the software zlib
processing in btrfs.  In case of memory pressure, fall back to a single
page buffer during workspace allocation.

The data compressed with larger input buffers will still conform to zlib
standard and thus can be decompressed also on a systems that uses only
PAGE_SIZE buffer for btrfs zlib.

Link: http://lkml.kernel.org/r/20200108105103.29028-1-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:40 -08:00
Omar Sandoval db72e47f79 btrfs: get rid of at_offset parameter to btrfs_lookup_bio_sums()
We can encode this in the offset parameter: -1 means use the page
offsets, anything else is a valid offset.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-20 16:40:54 +01:00
Omar Sandoval e62958fce9 btrfs: get rid of trivial __btrfs_lookup_bio_sums() wrappers
Currently, we have two wrappers for __btrfs_lookup_bio_sums():
btrfs_lookup_bio_sums_dio(), which is used for direct I/O, and
btrfs_lookup_bio_sums(), which is used everywhere else. The only
difference is that the _dio variant looks up csums starting at the given
offset instead of using the page index, which isn't actually direct
I/O-specific. Let's clean up the signature and return value of
__btrfs_lookup_bio_sums(), rename it to btrfs_lookup_bio_sums(), and get
rid of the trivial helpers.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-20 16:40:53 +01:00
Dennis Zhou 46bcff2bfc btrfs: fix compressed write bio blkcg attribution
Bio attribution is handled at bio_set_dev() as once we have a device, we
have a corresponding request_queue and then can derive the current css.
In special cases, we want to attribute to bio to someone else. This can
be done by calling bio_associate_blkg_from_css() or
kthread_associate_blkcg() depending on the scenario. Btrfs does this for
compressed writeback as they are handled by kworkers, so the latter can
be done here.

Commit 1a41802701 ("btrfs: drop bio_set_dev where not needed") removes
early bio_set_dev() calls prior to submit_stripe_bio(). This breaks the
above assumption that we'll have a request_queue when we are doing
association. To fix this, switch to using kthread_associate_blkcg().

Without this, we crash in btrfs/024:

  [ 3052.093088] BUG: kernel NULL pointer dereference, address: 0000000000000510
  [ 3052.107013] #PF: supervisor read access in kernel mode
  [ 3052.107014] #PF: error_code(0x0000) - not-present page
  [ 3052.107015] PGD 0 P4D 0
  [ 3052.107021] Oops: 0000 [#1] SMP
  [ 3052.138904] CPU: 42 PID: 201270 Comm: kworker/u161:0 Kdump: loaded Not tainted 5.5.0-rc1-00062-g4852d8ac90a9 #712
  [ 3052.138905] Hardware name: Quanta Tioga Pass Single Side 01-0032211004/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018
  [ 3052.138912] Workqueue: btrfs-delalloc btrfs_work_helper
  [ 3052.191375] RIP: 0010:bio_associate_blkg_from_css+0x1e/0x3c0
  [ 3052.191379] RSP: 0018:ffffc900210cfc90 EFLAGS: 00010282
  [ 3052.191380] RAX: 0000000000000000 RBX: ffff88bfe5573c00 RCX: 0000000000000000
  [ 3052.191382] RDX: ffff889db48ec2f0 RSI: ffff88bfe5573c00 RDI: ffff889db48ec2f0
  [ 3052.191386] RBP: 0000000000000800 R08: 0000000000203bb0 R09: ffff889db16b2400
  [ 3052.293364] R10: 0000000000000000 R11: ffff88a07fffde80 R12: ffff889db48ec2f0
  [ 3052.293365] R13: 0000000000001000 R14: ffff889de82bc000 R15: ffff889e2b7bdcc8
  [ 3052.293367] FS:  0000000000000000(0000) GS:ffff889ffba00000(0000) knlGS:0000000000000000
  [ 3052.293368] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [ 3052.293369] CR2: 0000000000000510 CR3: 0000000002611001 CR4: 00000000007606e0
  [ 3052.293370] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [ 3052.293371] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [ 3052.293372] PKRU: 55555554
  [ 3052.293376] Call Trace:
  [ 3052.402552]  btrfs_submit_compressed_write+0x137/0x390
  [ 3052.402558]  submit_compressed_extents+0x40f/0x4c0
  [ 3052.422401]  btrfs_work_helper+0x246/0x5a0
  [ 3052.422408]  process_one_work+0x200/0x570
  [ 3052.438601]  ? process_one_work+0x180/0x570
  [ 3052.438605]  worker_thread+0x4c/0x3e0
  [ 3052.438614]  kthread+0x103/0x140
  [ 3052.460735]  ? process_one_work+0x570/0x570
  [ 3052.460737]  ? kthread_mod_delayed_work+0xc0/0xc0
  [ 3052.460744]  ret_from_fork+0x24/0x30

Fixes: 1a41802701 ("btrfs: drop bio_set_dev where not needed")
Reported-by: Chris Murphy <chris@colorremedies.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-12-30 16:07:19 +01:00
Dennis Zhou 7b62e66cbb btrfs: punt all bios created in btrfs_submit_compressed_write()
Compressed writes happen in the background via kworkers. However, this
causes bios to be attributed to root bypassing any cgroup limits from
the actual writer. We tag the first bio with REQ_CGROUP_PUNT, which will
punt the bio to an appropriate cgroup specific workqueue and attribute
the IO properly. However, if btrfs_submit_compressed_write() creates a
new bio, we don't tag it the same way. Add the appropriate tagging for
subsequent bios.

Fixes: ec39f7696c ("Btrfs: use REQ_CGROUP_PUNT for worker thread submitted bios")
Reviewed-by: Chris Mason <clm@fb.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-12-30 16:07:16 +01:00
David Sterba 1a41802701 btrfs: drop bio_set_dev where not needed
bio_set_dev sets a bdev to a bio and is not only setting a pointer bug
also changing some state bits if there was a different bdev set before.
This is one thing that's not needed.

Another thing is that setting a bdev at bio allocation time is too early
and actually does not work with plain redundancy profiles, where each
time we submit a bio to a device, the bdev is set correctly.

In many places the bio bdev is set to latest_bdev that seems to serve as
a stub pointer "just to put something to bio". But we don't have to do
that.

Where do we know which bdev to set:

* for regular IO: submit_stripe_bio that's called by btrfs_map_bio

* repair IO: repair_io_failure, read or write from specific device

* super block write (using buffer_heads but uses raw bdev) and barriers

* scrub: this does not use all regular IO paths as it needs to reach all
  copies, verify and fixup eventually, and for that all bdev management
  is independent

* raid56: rbio_add_io_page, for the RMW write

* integrity-checker: does it's own low-level block tracking

Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 23:39:30 +01:00
David Sterba 0cf2521313 btrfs: compression: remove ops pointer from workspace_manager
We can infer the ops from the type that is now passed to all functions
that would need it, this makes workspace_manager::ops redundant and can
be removed.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:59 +01:00
David Sterba 1e00235160 btrfs: compression: inline free_workspace
Replace indirect calls to free_workspace by switch and calls to the
specific callbacks. This is mainly to get rid of the indirection due to
spectre vulnerability mitigations.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:59 +01:00
David Sterba a3bbd2a9ee btrfs: compression: pass type to btrfs_put_workspace
We can infer the workspace_manager from type and the type will be used
in the following patch to call a common helper for free_workspace.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:59 +01:00
David Sterba c778df1406 btrfs: compression: inline alloc_workspace
Replace indirect calls to alloc_workspace by switch and calls to the
specific callbacks. This is mainly to get rid of the indirection due to
spectre vulnerability mitigations.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:58 +01:00
David Sterba 5907a9bb13 btrfs: compression: pass type to btrfs_get_workspace
We can infer the workspace_manager from type and the type will be used
in the following patch to call a common helper for alloc_workspace.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:58 +01:00
David Sterba bd3a5287cc btrfs: compression: inline put_workspace
Similar to get_workspace, majority of the callbacks is trivial, we don't
gain anything by the indirection, so replace them by a switch function.
Trivial callback implementations use the helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:58 +01:00
David Sterba 6a0d12724b btrfs: compression: inline get_workspace
Majority of the callbacks is trivial, we don't gain anything by the
indirection, so replace them by a switch function.

ZLIB needs to adjust level in the callback and ZSTD workspace management
is complex, the rest is call to the helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:58 +01:00
David Sterba d20f395f98 btrfs: compression: export alloc/free/get/put callbacks of all algos
The indirect calls will be replaced by a switch in compression.c.
(Switch is faster than indirect calls with when Spectre mitigations are
enabled).

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:58 +01:00
David Sterba 2510307e6c btrfs: compression: inline cleanup_workspace_manager
Replace loop calling to all algos with a list of direct calls to the
cleanup manager callback. When that becomes trivial it is replaced by
direct call to the helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba 2dba714390 btrfs: compression: let workspace manager cleanup take only the type
With the access to the workspace structures, we can look it up together
with the compression ops inside the workspace manager cleanup helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba d551703347 btrfs: compression: inline init_workspace_manager
Replace loop calling to all algos with a list of direct calls to the
init manager callback. When that becomes trivial it is replaced by
direct call to the helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba 975db48330 btrfs: compression: let workspace manager init take only the type
With the access to the workspace structures, we can look it up together
with the compression ops inside the workspace manager init helper.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba be95104531 btrfs: compression: attach workspace manager to the ops
There's a lot of indirection when the generic code calls into
algo-specific callbacks to reach the private workspace manager structure
and back to the generic code.

To simplify that, export the workspace manager for heuristic, LZO and
ZLIB, while ZSTD is going to use it's own manager.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba 1e4eb74654 btrfs: switch compression callbacks to direct calls
The indirect calls bring some overhead due to spectre vulnerability
mitigations. The number of cases is small and below the threshold
(10-20) where indirect call would be better.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:57 +01:00
David Sterba c4bf665a31 btrfs: export compression and decompression callbacks
Export compress_pages, decompress_bio and decompress callbacks for all
compression algos. The indirect calls will be replaced by a switch.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:56 +01:00
Chengguang Xu ce96b7ffd1 btrfs: use better definition of number of compression type
The compression type upper limit constant is the same as the last value
and this is confusing.  In order to keep coding style consistent, use
BTRFS_NR_COMPRESS_TYPES as the total number that follows the idom of
'NR' being one more than the last value.

Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:55 +01:00
Chris Mason ec39f7696c Btrfs: use REQ_CGROUP_PUNT for worker thread submitted bios
Async CRCs and compression submit IO through helper threads, which means
they have IO priority inversions when cgroup IO controllers are in use.

This flags all of the writes submitted by btrfs helper threads as
REQ_CGROUP_PUNT.  submit_bio() will punt these to dedicated per-blkcg
work items to avoid the priority inversion.

For the compression code, we take a reference on the wbc's blkg css and
pass it down to the async workers.

For the async CRCs, the bio already has the correct css, we just need to
tell the block layer to use REQ_CGROUP_PUNT.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Chris Mason <clm@fb.com>
Modified-and-reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:53 +01:00
Chris Mason 08635bae0b Btrfs: stop using btrfs_schedule_bio()
btrfs_schedule_bio() hands IO off to a helper thread to do the actual
submit_bio() call.  This has been used to make sure async crc and
compression helpers don't get stuck on IO submission.  To maintain good
performance, over time the IO submission threads duplicated some IO
scheduler characteristics such as high and low priority IOs and they
also made some ugly assumptions about request allocation batch sizes.

All of this cost at least one extra context switch during IO submission,
and doesn't fit well with the modern blkmq IO stack.  So, this commit stops
using btrfs_schedule_bio().  We may need to adjust the number of async
helper threads for crcs and compression, but long term it's a better
path.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:52 +01:00
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
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
David Sterba e749af443f btrfs: lift bio_set_dev from bio allocation helpers
The block device is passed around for the only purpose to set it in new
bios. Move the assignment one level up. This is a preparatory patch for
further bdev cleanups.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-02 12:30:51 +02:00
Johannes Thumshirn aa53e3bfac btrfs: correctly validate compression type
Nikolay reported the following KASAN splat when running btrfs/048:

[ 1843.470920] ==================================================================
[ 1843.471971] BUG: KASAN: slab-out-of-bounds in strncmp+0x66/0xb0
[ 1843.472775] Read of size 1 at addr ffff888111e369e2 by task btrfs/3979

[ 1843.473904] CPU: 3 PID: 3979 Comm: btrfs Not tainted 5.2.0-rc3-default #536
[ 1843.475009] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 1843.476322] Call Trace:
[ 1843.476674]  dump_stack+0x7c/0xbb
[ 1843.477132]  ? strncmp+0x66/0xb0
[ 1843.477587]  print_address_description+0x114/0x320
[ 1843.478256]  ? strncmp+0x66/0xb0
[ 1843.478740]  ? strncmp+0x66/0xb0
[ 1843.479185]  __kasan_report+0x14e/0x192
[ 1843.479759]  ? strncmp+0x66/0xb0
[ 1843.480209]  kasan_report+0xe/0x20
[ 1843.480679]  strncmp+0x66/0xb0
[ 1843.481105]  prop_compression_validate+0x24/0x70
[ 1843.481798]  btrfs_xattr_handler_set_prop+0x65/0x160
[ 1843.482509]  __vfs_setxattr+0x71/0x90
[ 1843.483012]  __vfs_setxattr_noperm+0x84/0x130
[ 1843.483606]  vfs_setxattr+0xac/0xb0
[ 1843.484085]  setxattr+0x18c/0x230
[ 1843.484546]  ? vfs_setxattr+0xb0/0xb0
[ 1843.485048]  ? __mod_node_page_state+0x1f/0xa0
[ 1843.485672]  ? _raw_spin_unlock+0x24/0x40
[ 1843.486233]  ? __handle_mm_fault+0x988/0x1290
[ 1843.486823]  ? lock_acquire+0xb4/0x1e0
[ 1843.487330]  ? lock_acquire+0xb4/0x1e0
[ 1843.487842]  ? mnt_want_write_file+0x3c/0x80
[ 1843.488442]  ? debug_lockdep_rcu_enabled+0x22/0x40
[ 1843.489089]  ? rcu_sync_lockdep_assert+0xe/0x70
[ 1843.489707]  ? __sb_start_write+0x158/0x200
[ 1843.490278]  ? mnt_want_write_file+0x3c/0x80
[ 1843.490855]  ? __mnt_want_write+0x98/0xe0
[ 1843.491397]  __x64_sys_fsetxattr+0xba/0xe0
[ 1843.492201]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[ 1843.493201]  do_syscall_64+0x6c/0x230
[ 1843.493988]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 1843.495041] RIP: 0033:0x7fa7a8a7707a
[ 1843.495819] Code: 48 8b 0d 21 de 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 be 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ee dd 2b 00 f7 d8 64 89 01 48
[ 1843.499203] RSP: 002b:00007ffcb73bca38 EFLAGS: 00000202 ORIG_RAX: 00000000000000be
[ 1843.500210] RAX: ffffffffffffffda RBX: 00007ffcb73bda9d RCX: 00007fa7a8a7707a
[ 1843.501170] RDX: 00007ffcb73bda9d RSI: 00000000006dc050 RDI: 0000000000000003
[ 1843.502152] RBP: 00000000006dc050 R08: 0000000000000000 R09: 0000000000000000
[ 1843.503109] R10: 0000000000000002 R11: 0000000000000202 R12: 00007ffcb73bda91
[ 1843.504055] R13: 0000000000000003 R14: 00007ffcb73bda82 R15: ffffffffffffffff

[ 1843.505268] Allocated by task 3979:
[ 1843.505771]  save_stack+0x19/0x80
[ 1843.506211]  __kasan_kmalloc.constprop.5+0xa0/0xd0
[ 1843.506836]  setxattr+0xeb/0x230
[ 1843.507264]  __x64_sys_fsetxattr+0xba/0xe0
[ 1843.507886]  do_syscall_64+0x6c/0x230
[ 1843.508429]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

[ 1843.509558] Freed by task 0:
[ 1843.510188] (stack is not available)

[ 1843.511309] The buggy address belongs to the object at ffff888111e369e0
                which belongs to the cache kmalloc-8 of size 8
[ 1843.514095] The buggy address is located 2 bytes inside of
                8-byte region [ffff888111e369e0, ffff888111e369e8)
[ 1843.516524] The buggy address belongs to the page:
[ 1843.517561] page:ffff88813f478d80 refcount:1 mapcount:0 mapping:ffff88811940c300 index:0xffff888111e373b8 compound_mapcount: 0
[ 1843.519993] flags: 0x4404000010200(slab|head)
[ 1843.520951] raw: 0004404000010200 ffff88813f48b008 ffff888119403d50 ffff88811940c300
[ 1843.522616] raw: ffff888111e373b8 000000000016000f 00000001ffffffff 0000000000000000
[ 1843.524281] page dumped because: kasan: bad access detected

[ 1843.525936] Memory state around the buggy address:
[ 1843.526975]  ffff888111e36880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1843.528479]  ffff888111e36900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1843.530138] >ffff888111e36980: fc fc fc fc fc fc fc fc fc fc fc fc 02 fc fc fc
[ 1843.531877]                                                        ^
[ 1843.533287]  ffff888111e36a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1843.534874]  ffff888111e36a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1843.536468] ==================================================================

This is caused by supplying a too short compression value ('lz') in the
test-case and comparing it to 'lzo' with strncmp() and a length of 3.
strncmp() read past the 'lz' when looking for the 'o' and thus caused an
out-of-bounds read.

Introduce a new check 'btrfs_compress_is_valid_type()' which not only
checks the user-supplied value against known compression types, but also
employs checks for too short values.

Reported-by: Nikolay Borisov <nborisov@suse.com>
Fixes: 272e5326c7 ("btrfs: prop: fix vanished compression property after failed set")
CC: stable@vger.kernel.org # 5.1+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-02 12:30:48 +02:00
Johannes Thumshirn ea41d6b278 btrfs: remove assumption about csum type form btrfs_print_data_csum_error()
btrfs_print_data_csum_error() still assumed checksums to be 32 bit in
size.  Make it size agnostic.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-01 13:35:02 +02:00
Johannes Thumshirn d5178578bc btrfs: directly call into crypto framework for checksumming
Currently btrfs_csum_data() relied on the crc32c() wrapper around the
crypto framework for calculating the CRCs.

As we have our own crypto_shash structure in the fs_info now, we can
directly call into the crypto framework without going trough the wrapper.

This way we can even remove the btrfs_csum_data() and btrfs_csum_final()
wrappers.

The module dependency on crc32c is preserved via MODULE_SOFTDEP("pre:
crc32c"), which was previously provided by LIBCRC32C config option doing
the same.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-01 13:35:02 +02:00