linux-toradex.git/fs/squashfs, branch v5.17

squashfs: provide backing_dev_info in order to disable read-ahead

2022-01-15T14:30:24+00:00

Commit c1f6925e1091 ("mm: put readahead pages in cache earlier") causes
the read performance of squashfs to deteriorate.Through testing, we find
that the performance will be back by closing the readahead of squashfs.

So we want to learn the way of ubifs, provides backing_dev_info and
disable read-ahead

We tested the following data by fio.
squashfs image blocksize=128K
test command:

  fio --name basic --bs=? --filename="/mnt/test_file" --rw=? --iodepth=1 --ioengine=psync --runtime=200 --time_based

  turn on squashfs readahead in 5.10 kernel
  bs(k)      read/randread           MB/s
  4            randread              271
  128          randread              231
  1024         randread              246
  4            read                  310
  128          read                  245
  1024         read                  247

  turn off squashfs readahead in 5.10 kernel
  bs(k)      read/randread           MB/s
  4            randread              293
  128          randread              330
  1024         randread              363
  4            read                  338
  128          read                  360
  1024         read                  365

  turn on squashfs readahead and revert the
  commit c1f6925e1091("mm: put readahead
  pages in cache earlier") in 5.10 kernel
  bs(k)      read/randread           MB/s
  4           randread               289
  128         randread               306
  1024        randread               335
  4           read                   337
  128         read                   336
  1024        read                   338

Link: https://lkml.kernel.org/r/20211116113141.1391026-1-zhengliang6@huawei.com
Signed-off-by: Zheng Liang 
Reviewed-by: Phillip Lougher 
Cc: Zhang Yi 
Cc: Hou Tao 
Cc: Miao Xie 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: zstd: Add kernel-specific API

2021-11-09T00:55:21+00:00

This patch:
- Moves `include/linux/zstd.h` -> `include/linux/zstd_lib.h`
- Updates modified zstd headers to yearless copyright
- Adds a new API in `include/linux/zstd.h` that is functionally
  equivalent to the in-use subset of the current API. Functions are
  renamed to avoid symbol collisions with zstd, to make it clear it is
  not the upstream zstd API, and to follow the kernel style guide.
- Updates all callers to use the new API.

There are no functional changes in this patch. Since there are no
functional change, I felt it was okay to update all the callers in a
single patch. Once the API is approved, the callers are mechanically
changed.

This patch is preparing for the 3rd patch in this series, which updates
zstd to version 1.4.10. Since the upstream zstd API is no longer exposed
to callers, the update can happen transparently.

Signed-off-by: Nick Terrell 
Tested By: Paul Jones 
Tested-by: Oleksandr Natalenko 
Tested-by: Sedat Dilek  # LLVM/Clang v13.0.0 on x86-64
Tested-by: Jean-Denis Girard

squashfs: use bdev_nr_bytes instead of open coding it

2021-10-18T20:43:23+00:00

Use the proper helper to read the block device size.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Kees Cook 
Acked-by: Phillip Lougher 
Link: https://lore.kernel.org/r/20211018101130.1838532-24-hch@lst.de
Signed-off-by: Jens Axboe

squashfs: use bvec_virt

2021-08-16T16:50:32+00:00

Use bvec_virt instead of open coding it.

Signed-off-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20210804095634.460779-7-hch@lst.de
Signed-off-by: Jens Axboe

squashfs: add option to panic on errors

2021-06-29T17:53:46+00:00

Add an errors=panic mount option to make squashfs trigger a panic when
errors are encountered, similar to several other filesystems.  This allows
a kernel dump to be saved using which the corruption can be analysed and
debugged.

Inspired by a pre-fs_context patch by Anton Eliasson.

Link: https://lkml.kernel.org/r/20210527125019.14511-1-vincent.whitchurch@axis.com
Signed-off-by: Vincent Whitchurch 
Signed-off-by: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

squashfs: fix divide error in calculate_skip()

2021-05-15T02:41:32+00:00

Sysbot has reported a "divide error" which has been identified as being
caused by a corrupted file_size value within the file inode.  This value
has been corrupted to a much larger value than expected.

Calculate_skip() is passed i_size_read(inode) >> msblk->block_log.  Due to
the file_size value corruption this overflows the int argument/variable in
that function, leading to the divide error.

This patch changes the function to use u64.  This will accommodate any
unexpectedly large values due to corruption.

The value returned from calculate_skip() is clamped to be never more than
SQUASHFS_CACHED_BLKS - 1, or 7.  So file_size corruption does not lead to
an unexpectedly large return result here.

Link: https://lkml.kernel.org/r/20210507152618.9447-1-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher 
Reported-by: 
Reported-by: 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

squashfs: fix xattr id and id lookup sanity checks

2021-03-25T16:22:55+00:00

The checks for maximum metadata block size is missing
SQUASHFS_BLOCK_OFFSET (the two byte length count).

Link: https://lkml.kernel.org/r/2069685113.2081245.1614583677427@webmail.123-reg.co.uk
Fixes: f37aa4c7366e23f ("squashfs: add more sanity checks in id lookup")
Signed-off-by: Phillip Lougher 
Cc: Sean Nyekjaer 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

squashfs: fix inode lookup sanity checks

2021-03-25T16:22:55+00:00

When mouting a squashfs image created without inode compression it fails
with: "unable to read inode lookup table"

It turns out that the BLOCK_OFFSET is missing when checking the
SQUASHFS_METADATA_SIZE agaist the actual size.

Link: https://lkml.kernel.org/r/20210226092903.1473545-1-sean@geanix.com
Fixes: eabac19e40c0 ("squashfs: add more sanity checks in inode lookup")
Signed-off-by: Sean Nyekjaer 
Acked-by: Phillip Lougher 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

block: rename BIO_MAX_PAGES to BIO_MAX_VECS

2021-03-11T14:47:48+00:00

Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed.  Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Matthew Wilcox (Oracle) 
Reviewed-by: Martin K. Petersen 
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe

squashfs: add more sanity checks in xattr id lookup

2021-02-10T01:26:44+00:00

Sysbot has reported a warning where a kmalloc() attempt exceeds the
maximum limit.  This has been identified as corruption of the xattr_ids
count when reading the xattr id lookup table.

This patch adds a number of additional sanity checks to detect this
corruption and others.

1. It checks for a corrupted xattr index read from the inode.  This could
   be because the metadata block is uncompressed, or because the
   "compression" bit has been corrupted (turning a compressed block
   into an uncompressed block).  This would cause an out of bounds read.

2. It checks against corruption of the xattr_ids count.  This can either
   lead to the above kmalloc failure, or a smaller than expected
   table to be read.

3. It checks the contents of the index table for corruption.

[phillip@squashfs.org.uk: fix checkpatch issue]
  Link: https://lkml.kernel.org/r/270245655.754655.1612770082682@webmail.123-reg.co.uk

Link: https://lkml.kernel.org/r/20210204130249.4495-5-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher 
Reported-by: syzbot+2ccea6339d368360800d@syzkaller.appspotmail.com
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds