linux.git/fs/erofs, branch v5.5

Merge tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

2019-12-11T20:25:32+00:00

Pull erofs fixes from Gao Xiang:
 "Mainly address a regression reported by David recently observed
  together with overlayfs due to the improper return value of
  listxattr() without xattr. Update outdated expressions in document as
  well.

  Summary:

   - Fix improper return value of listxattr() with no xattr

   - Keep up documentation with latest code"

* tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: update documentation
  erofs: zero out when listxattr is called with no xattr

erofs: zero out when listxattr is called with no xattr

2019-12-04T13:15:04+00:00

As David reported [1], ENODATA returns when attempting
to modify files by using EROFS as an overlayfs lower layer.

The root cause is that listxattr could return unexpected
-ENODATA by mistake for inodes without xattr. That breaks
listxattr return value convention and it can cause copy
up failure when used with overlayfs.

Resolve by zeroing out if no xattr is found for listxattr.

[1] https://lore.kernel.org/r/CAEvUa7nxnby+rxK-KRMA46=exeOMApkDMAV08AjMkkPnTPV4CQ@mail.gmail.com
Link: https://lore.kernel.org/r/20191201084040.29275-1-hsiangkao@aol.com
Fixes: cadf1ccf1b00 ("staging: erofs: add error handling for xattr submodule")
Cc:  # 4.19+
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: remove unnecessary output in erofs_show_options()

2019-11-24T03:02:41+00:00

We have already handled cache_strategy option carefully,
so incorrect setting could not pass option parsing.
Meanwhile, print 'cache_strategy=(unknown)' can cause
failure on remount.

Link: https://lore.kernel.org/r/20191119115049.3401-1-cgxu519@mykernel.net
Signed-off-by: Chengguang Xu 
Reviewed-by: Gao Xiang 
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: drop all vle annotations for runtime names

2019-11-24T03:02:41+00:00

VLE was an old informal name of fixed-sized output
compression which came from published ATC'19 paper [1].

Drop those old annotations since erofs can handle
all encoded clusters in block-aligned basis, which
is wider than fixed-sized output compression after
larger clustersize feature is fully implemented.

Unaligned encoding won't be considered in EROFS
since it's not friendly to inplace I/O and perhaps
decompression inplace.

a) Fixed-sized output compression with 16KB pcluster:
  ___________________________________
 |xxxxxxxx|xxxxxxxx|xxxxxxxx|xxxxxxxx|
 |___ 0___|___ 1___|___ 2___|___ 3___| physical blocks

b) Block-aligned fixed-sized input compression with
   16KB pcluster:
  ___________________________________
 |xxxxxxxx|xxxxxxxx|xxxxxxxx|xxx00000|
 |___ 0___|___ 1___|___ 2___|___ 3___| physical blocks

c) Block-unaligned fixed-sized input compression with
   16KB compression unit:
  ____________________________________________
 |..xxxxxx|xxxxxxxx|xxxxxxxx|xxxxxxxx|x.......|
 |___ 0___|___ 1___|___ 2___|___ 3___|___ 4___| physical blocks

Refine better names for those as well.

[1] https://www.usenix.org/conference/atc19/presentation/gao

Link: https://lore.kernel.org/r/20191108033733.63919-1-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: support superblock checksum

2019-11-24T03:02:41+00:00

Introduce superblock checksum feature in order to
check at mounting time.

Note that the first 1024 bytes are ignore for x86
boot sectors and other oddities.

Link: https://lore.kernel.org/r/20191104024937.113939-1-gaoxiang25@huawei.com
Signed-off-by: Pratik Shinde 
Reviewed-by: Chao Yu 
Cc: Dan Carpenter 
Signed-off-by: Gao Xiang

erofs: set iowait for sync decompression

2019-11-24T03:02:41+00:00

For those tasks waiting I/O for sync decompression,
they should be better marked as IO wait state.

Link: https://lore.kernel.org/r/20191008125616.183715-5-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: clean up decompress queue stuffs

2019-11-24T03:02:41+00:00

Previously, both z_erofs_unzip_io and z_erofs_unzip_io_sb
record decompress queues for backend to use.

The only difference is that z_erofs_unzip_io is used for
on-stack sync decompression so that it doesn't have a super
block field (since the caller can pass it in its context),
but it increases complexity with only a pointer saving.

Rename z_erofs_unzip_io to z_erofs_decompressqueue with
a fixed super_block member and kill the other entirely,
and it can fallback to sync decompression if memory
allocation failure.

Link: https://lore.kernel.org/r/20191008125616.183715-4-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: get rid of __stagingpage_alloc helper

2019-11-24T02:57:48+00:00

Now open code is much cleaner due to iterative development.

Link: https://lore.kernel.org/r/20191124025217.12345-1-hsiangkao@aol.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: remove dead code since managed cache is now built-in

2019-10-15T16:07:56+00:00

After commit 4279f3f9889f ("staging: erofs: turn cache
strategies into mount options"), cache strategies are
changed into mount options rather than old build configs.

Let's kill useless code for obsoleted build options.

Link: https://lore.kernel.org/r/20191008125616.183715-2-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang

erofs: clean up collection handling routines

2019-10-15T16:07:48+00:00

 - change return value to int since collection is
   already returned within the collector.
 - better function naming.

Link: https://lore.kernel.org/r/20191008125616.183715-1-gaoxiang25@huawei.com
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang