Commit graph

91 commits

Author SHA1 Message Date
Linus Torvalds
dc483c851f Changes since last update:
- Add per-cpu kthreads for low-latency decompression for Android
    use cases;
 
  - Get rid of tagged pointer helpers since they are rarely used now;
 
  - Several code cleanups to reduce codebase;
 
  - Documentation and MAINTAINERS updates.
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Merge tag 'erofs-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs updates from Gao Xiang:
 "The most noticeable feature for this cycle is per-CPU kthread
  decompression since Android use cases need low-latency I/O handling in
  order to ensure the app runtime performance, currently unbounded
  workqueue latencies are not quite good for production on many aarch64
  hardwares and thus we need to introduce a deterministic expectation
  for these. Decompression is CPU-intensive and it is sleepable for
  EROFS, so other alternatives like decompression under softirq contexts
  are not considered. More details are in the corresponding commit
  message.

  Others are random cleanups around the whole codebase and we will
  continue to clean up further in the next few months.

  Due to Lunar New Year holidays, some other new features were not
  completely reviewed and solidified as expected and we may delay them
  into the next version.

  Summary:

   - Add per-cpu kthreads for low-latency decompression for Android use
     cases

   - Get rid of tagged pointer helpers since they are rarely used now

   - Several code cleanups to reduce codebase

   - Documentation and MAINTAINERS updates"

* tag 'erofs-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: (21 commits)
  erofs: fix an error code in z_erofs_init_zip_subsystem()
  erofs: unify anonymous inodes for blob
  erofs: relinquish volume with mutex held
  erofs: maintain cookies of share domain in self-contained list
  erofs: remove unused device mapping in meta routine
  MAINTAINERS: erofs: Add Documentation/ABI/testing/sysfs-fs-erofs
  Documentation/ABI: sysfs-fs-erofs: update supported features
  erofs: remove unused EROFS_GET_BLOCKS_RAW flag
  erofs: update print symbols for various flags in trace
  erofs: make kobj_type structures constant
  erofs: add per-cpu threads for decompression as an option
  erofs: tidy up internal.h
  erofs: get rid of z_erofs_do_map_blocks() forward declaration
  erofs: move zdata.h into zdata.c
  erofs: remove tagged pointer helpers
  erofs: avoid tagged pointers to mark sync decompression
  erofs: get rid of erofs_inode_datablocks()
  erofs: simplify iloc()
  erofs: get rid of debug_one_dentry()
  erofs: remove linux/buffer_head.h dependency
  ...
2023-02-20 12:23:40 -08:00
Jingbo Xu
61fef98945 erofs: unify anonymous inodes for blob
Currently there're two anonymous inodes (inode and anon_inode in struct
erofs_fscache) for each blob.  The former was introduced as the
address_space of page cache for bootstrap.

The latter was initially introduced as both the address_space of page
cache and also a sentinel in the shared domain.  Since now the management
of cookies in share domain has been decoupled with the anonymous inode,
there's no need to maintain an extra anonymous inode.  Let's unify these
two anonymous inodes.

Besides, in non-share-domain mode only bootstrap will allocate anonymous
inode.  To simplify the implementation, always allocate anonymous inode
for both bootstrap and data blobs.  Similarly release anonymous inodes
for data blobs when .put_super() is called, or we'll get "VFS: Busy
inodes after unmount." warning.

Also remove the redundant set_nlink() when initializing the anonymous
inode, since i_nlink has already been initialized to 1 when the inode
gets allocated.

Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20230209063913.46341-5-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:11:28 +08:00
Jingbo Xu
2dfb8c3b12 erofs: maintain cookies of share domain in self-contained list
We'd better not touch sb->s_inodes list and inode->i_count directly.
Let's maintain cookies of share domain in a self-contained list in erofs.

Besides, relinquish cookie with the mutex held.  Otherwise if a cookie
is registered when the old cookie with the same name in the same domain
has been removed from the list but not relinquished yet, fscache may
complain "Duplicate cookie detected".

Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20230209063913.46341-3-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:11:27 +08:00
Jingbo Xu
8b58f9f021 erofs: remove unused EROFS_GET_BLOCKS_RAW flag
For erofs_map_blocks() and erofs_map_blocks_flatmode(), the flags
argument is always EROFS_GET_BLOCKS_RAW.  Thus remove the unused flags
parameter for these two functions.

Besides EROFS_GET_BLOCKS_RAW is originally introduced for reading
compressed (raw) data for compressed files.  However it's never used
actually and let's remove it now.

Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230209024825.17335-2-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:11:26 +08:00
Gao Xiang
557afdd94c erofs: tidy up internal.h
Reorder internal.h code so that removing unneeded macros and more.
No logic changes.

Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230204093040.97967-6-hsiangkao@linux.alibaba.com
2023-02-15 08:11:25 +08:00
Gao Xiang
4efdec36dc erofs: get rid of erofs_inode_datablocks()
erofs_inode_datablocks() has the only one caller, let's just get
rid of it entirely.  No logic changes.

Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230204093040.97967-1-hsiangkao@linux.alibaba.com
2023-02-15 08:11:24 +08:00
Gao Xiang
b780d3fc61 erofs: simplify iloc()
Actually we could pass in inodes directly to clean up all callers.
Also rename iloc() as erofs_iloc().

Link: https://lore.kernel.org/r/20230114150823.432069-1-xiang@kernel.org
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:11:24 +08:00
Gao Xiang
768bb10afb erofs: remove linux/buffer_head.h dependency
EROFS actually never uses buffer heads, therefore just get rid of
BH_xxx definitions and linux/buffer_head.h inclusive.

Link: https://lore.kernel.org/r/20230113065226.68801-2-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:11:10 +08:00
Gao Xiang
7c3511a2c8 erofs: clean up erofs_iget()
Move inode hash function into inode.c and simplify erofs_iget().

Link: https://lore.kernel.org/r/20230113065226.68801-1-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2023-02-15 08:10:46 +08:00
Christian Brauner
b74d24f7a7
fs: port ->getattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Gao Xiang
927e5010ff erofs: use kmap_local_page() only for erofs_bread()
Convert all mapped erofs_bread() users to use kmap_local_page()
instead of kmap() or kmap_atomic().

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-and-tested-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20221018105313.4940-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-12-07 10:56:31 +08:00
Hou Tao
27f2a2dcc6 erofs: check the uniqueness of fsid in shared domain in advance
When shared domain is enabled, doing mount twice with the same fsid and
domain_id will trigger sysfs warning as shown below:

 sysfs: cannot create duplicate filename '/fs/erofs/d0,meta.bin'
 CPU: 15 PID: 1051 Comm: mount Not tainted 6.1.0-rc6+ #1
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
 Call Trace:
  <TASK>
  dump_stack_lvl+0x38/0x49
  dump_stack+0x10/0x12
  sysfs_warn_dup.cold+0x17/0x27
  sysfs_create_dir_ns+0xb8/0xd0
  kobject_add_internal+0xb1/0x240
  kobject_init_and_add+0x71/0xa0
  erofs_register_sysfs+0x89/0x110
  erofs_fc_fill_super+0x98c/0xaf0
  vfs_get_super+0x7d/0x100
  get_tree_nodev+0x16/0x20
  erofs_fc_get_tree+0x20/0x30
  vfs_get_tree+0x24/0xb0
  path_mount+0x2fa/0xa90
  do_mount+0x7c/0xa0
  __x64_sys_mount+0x8b/0xe0
  do_syscall_64+0x30/0x60
  entry_SYSCALL_64_after_hwframe+0x46/0xb0

The reason is erofs_fscache_register_cookie() doesn't guarantee the primary
data blob (aka fsid) is unique in the shared domain and
erofs_register_sysfs() invoked by the second mount will fail due to the
duplicated fsid in the shared domain and report warning.

It would be better to check the uniqueness of fsid before doing
erofs_register_sysfs(), so adding a new flags parameter for
erofs_fscache_register_cookie() and doing the uniqueness check if
EROFS_REG_COOKIE_NEED_NOEXIST is enabled.

After the patch, the error in dmesg for the duplicated mount would be:

 erofs: ...: erofs_domain_register_cookie: XX already exists in domain YY

Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20221125110822.3812942-1-houtao@huaweicloud.com
Fixes: 7d41963759 ("erofs: Support sharing cookies in the same domain")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-12-07 10:53:40 +08:00
Jingbo Xu
39bfcb8138 erofs: fix use-after-free of fsid and domain_id string
When erofs instance is remounted with fsid or domain_id mount option
specified, the original fsid and domain_id string pointer in sbi->opt
is directly overridden with the fsid and domain_id string in the new
fs_context, without freeing the original fsid and domain_id string.
What's worse, when the new fsid and domain_id string is transferred to
sbi, they are not reset to NULL in fs_context, and thus they are freed
when remount finishes, while sbi is still referring to these strings.

Reconfiguration for fsid and domain_id seems unusual. Thus clarify this
restriction explicitly and dump a warning when users are attempting to
do this.

Besides, to fix the use-after-free issue, move fsid and domain_id from
erofs_mount_opts to outside.

Fixes: c6be2bd0a5 ("erofs: register fscache volume")
Fixes: 8b7adf1dff ("erofs: introduce fscache-based domain")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20221021023153.1330-1-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-11-10 09:53:20 +08:00
Gao Xiang
312fe643ad erofs: clean up erofs_iget()
isdir indicated REQ_META|REQ_PRIO which no longer works now.
Get rid of isdir entirely.

Link: https://lore.kernel.org/r/20220927063607.54832-2-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-27 17:27:45 +08:00
Gao Xiang
53a7f9961c erofs: clean up unnecessary code and comments
Some conditional macros and comments are useless.

Link: https://lore.kernel.org/r/20220927063607.54832-1-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-27 17:27:25 +08:00
Gao Xiang
5c2a64252c erofs: introduce partial-referenced pclusters
Due to deduplication for compressed data, pclusters can be partially
referenced with their prefixes.

Together with the user-space implementation, it enables EROFS
variable-length global compressed data deduplication with rolling
hash.

Link: https://lore.kernel.org/r/20220923014915.4362-1-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-26 23:55:43 +08:00
Yue Hu
b15b2e307c erofs: support on-disk compressed fragments data
Introduce on-disk compressed fragments data feature.

This approach adds a new field called `h_fragmentoff' in the per-file
compression header to indicate the fragment offset of each tail pcluster
or the whole file in the special packed inode.

Similar to ztailpacking, it will also find and record the 'headlcn'
of the tail pcluster when initializing per-inode zmap for making
follow-on requests more easy.

Signed-off-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/YzHKxcFTlHGgXeH9@B-P7TQMD6M-0146.local
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-26 23:55:39 +08:00
Yue Hu
fdffc091e6 erofs: support interlaced uncompressed data for compressed files
Currently, uncompressed data is all handled in the shifted way, which
means we have to shift the whole on-disk plain pcluster to get the
logical data.   However, since we are also using in-place I/O for
uncompressed data, data copy will be reduced a lot if pcluster is
recorded in the interlaced way as illustrated below:
 _______________________________________________________________
|               |    |               |_ tail part |_ head part _|
|<-   blk0    ->| .. |<-   blkn-2  ->|<-         blkn-1       ->|

The logical data then becomes:
 ________________________________________________________
|_ head part _|_  blk0  _| .. |_  blkn-2  _|_ tail part _|

In addition, non-4k plain pclusters are also survived by the
interlaced way, which can be used for non-4k lclusters as well.

However, it's almost impossible to de-duplicate uncompressed data
in the interlaced way, therefore shifted uncompressed data is still
useful.

Signed-off-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/8369112678604fdf4ef796626d59b1fdd0745a53.1663898962.git.huyue2@coolpad.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-23 10:55:56 +08:00
Jia Zhu
7d41963759 erofs: Support sharing cookies in the same domain
Several erofs filesystems can belong to one domain, and data blobs can
be shared among these erofs filesystems of same domain.

Users could specify domain_id mount option to create or join into a
domain.

Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918110150.6338-1-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-20 08:01:54 +08:00
Jia Zhu
a9849560c5 erofs: introduce a pseudo mnt to manage shared cookies
Use a pseudo mnt to manage shared cookies.

Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918043456.147-5-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-20 08:01:54 +08:00
Jia Zhu
8b7adf1dff erofs: introduce fscache-based domain
A new fscache-based shared domain mode is going to be introduced for
erofs. In which case, same data blobs in same domain will be shared
and reused to reduce on-disk space usage.

The implementation of sharing blobs will be introduced in subsequent
patches.

Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918043456.147-4-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-20 08:01:53 +08:00
Jia Zhu
e1de2da0b7 erofs: code clean up for fscache
Some cleanups. No logic changes.

Suggested-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918043456.147-3-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-20 08:01:53 +08:00
Gao Xiang
2f44013e39 erofs: fix pcluster use-after-free on UP platforms
During stress testing with CONFIG_SMP disabled, KASAN reports as below:

==================================================================
BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30
Read of size 8 at addr ffff8881094223f8 by task stress/7789

CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
Call Trace:
 <TASK>
..
 __mutex_lock+0xe5/0xc30
..
 z_erofs_do_read_page+0x8ce/0x1560
..
 z_erofs_readahead+0x31c/0x580
..
Freed by task 7787
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x20/0x30
 kasan_set_free_info+0x20/0x40
 __kasan_slab_free+0x10c/0x190
 kmem_cache_free+0xed/0x380
 rcu_core+0x3d5/0xc90
 __do_softirq+0x12d/0x389

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40
 __kasan_record_aux_stack+0x97/0xb0
 call_rcu+0x3d/0x3f0
 erofs_shrink_workstation+0x11f/0x210
 erofs_shrink_scan+0xdc/0x170
 shrink_slab.constprop.0+0x296/0x530
 drop_slab+0x1c/0x70
 drop_caches_sysctl_handler+0x70/0x80
 proc_sys_call_handler+0x20a/0x2f0
 vfs_write+0x555/0x6c0
 ksys_write+0xbe/0x160
 do_syscall_64+0x3b/0x90

The root cause is that erofs_workgroup_unfreeze() doesn't reset to
orig_val thus it causes a race that the pcluster reuses unexpectedly
before freeing.

Since UP platforms are quite rare now, such path becomes unnecessary.
Let's drop such specific-designed path directly instead.

Fixes: 73f5c66df3 ("staging: erofs: fix `erofs_workgroup_{try_to_freeze, unfreeze}'")
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220902045710.109530-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-09-05 23:23:30 +08:00
Jeffle Xu
1442b02b66 erofs: implement fscache-based data read for non-inline layout
Implement the data plane of reading data from data blobs over fscache
for non-inline layout.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-19-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:20 +08:00
Jeffle Xu
955b478e1b erofs: register fscache context for extra data blobs
Similar to the multi-device mode, erofs could be mounted from one
primary data blob (mandatory) and multiple extra data blobs (optional).

Register fscache context for each extra data blob.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-17-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:20 +08:00
Jeffle Xu
37c90c5fae erofs: register fscache context for primary data blob
Registers fscache context for primary data blob. Also move the
initialization of s_op and related fields forward, since anonymous
inode will be allocated under the super block when registering the
fscache context.

Something worth mentioning about the cleanup routine.

1. The fscache context will instantiate anonymous inodes under the super
block. Release these anonymous inodes when .put_super() is called, or
we'll get "VFS: Busy inodes after unmount." warning.

2. The fscache context is initialized prior to the root inode. If
.kill_sb() is called when mount failed, .put_super() won't be called
when root inode has not been initialized yet. Thus .kill_sb() shall
also contain the cleanup routine.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-16-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:20 +08:00
Jeffle Xu
3c265d7dce erofs: add anonymous inode caching metadata for data blobs
Introduce one anonymous inode for data blobs so that erofs can cache
metadata directly within such anonymous inode.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-14-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:19 +08:00
Jeffle Xu
b02c602f06 erofs: add fscache context helper functions
Introduce a context structure for managing data blobs, and helper
functions for initializing and cleaning up this context structure.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-13-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:19 +08:00
Jeffle Xu
c6be2bd0a5 erofs: register fscache volume
A new fscache based mode is going to be introduced for erofs, in which
case on-demand read semantics is implemented through fscache.

As the first step, register fscache volume for each erofs filesystem.
That means, data blobs can not be shared among erofs filesystems. In the
following iteration, we are going to introduce the domain semantics, in
which case several erofs filesystems can belong to one domain, and data
blobs can be shared among these erofs filesystems of one domain.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-12-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:19 +08:00
Jeffle Xu
93b856bb5f erofs: add fscache mode check helper
Until then erofs is exactly blockdev based filesystem.

A new fscache-based mode is going to be introduced for erofs to support
scenarios where on-demand read semantics is needed, e.g. container
image distribution. In this case, erofs could be mounted from data blobs
through fscache.

Add a helper checking which mode erofs works in, and twist the code in
preparation for the upcoming fscache mode.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-11-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:19 +08:00
Jeffle Xu
94d7894670 erofs: make erofs_map_blocks() generally available
... so that it can be used in the following introduced fscache mode.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-10-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-18 00:11:18 +08:00
Hongnan Li
3e917cc305 erofs: make filesystem exportable
Implement export operations in order to make EROFS support accessing
inodes with filehandles so that it can be exported via NFS and used
by overlayfs.

Without this patch, 'exportfs -rv' will report:
exportfs: /root/erofs_mp does not support NFS export

Also tested with unionmount-testsuite and the testcase below passes now:
./run --ov --erofs --verify hard-link

For more details about the testcase, see:
https://github.com/amir73il/unionmount-testsuite/pull/6

Signed-off-by: Hongnan Li <hongnan.li@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220425040712.91685-1-hongnan.li@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17 23:48:54 +08:00
Gao Xiang
1f7aa6caef erofs: remove obsoleted comments
Some comments haven't been useful anymore since the code updated.
Let's drop them instead.

Link: https://lore.kernel.org/r/20220506194612.117120-2-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17 23:38:13 +08:00
Gao Xiang
fe5de5859d erofs: use meta buffers for reading directories
Previously, directory inodes are directly handled with page cache
interfaces.

In order to support sub-page directory blocks and folios, let's
convert them into the latest metabuf infrastructure as well and
this patch addresses the readdir case first.

Link: https://lore.kernel.org/r/20220316012246.95131-1-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-03-17 00:09:02 +08:00
Gao Xiang
22ba5e99b9 erofs: fix ztailpacking on > 4GiB filesystems
z_idataoff here is an absolute physical offset, so it should use
erofs_off_t (64 bits at least). Otherwise, it'll get trimmed and
cause the decompresion failure.

Link: https://lore.kernel.org/r/20220222033118.20540-1-hsiangkao@linux.alibaba.com
Fixes: ab92184ff8 ("erofs: add on-disk compressed tail-packing inline support")
Reviewed-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-03-02 21:58:45 +08:00
Linus Torvalds
3acbdbf42e dax + libnvdimm for v5.17
- Simplify the dax_operations API
   - Eliminate bdev_dax_pgoff() in favor of the filesystem maintaining
     and applying a partition offset to all its DAX iomap operations.
   - Remove wrappers and device-mapper stacked callbacks for
     ->copy_from_iter() and ->copy_to_iter() in favor of moving
     block_device relative offset responsibility to the
     dax_direct_access() caller.
   - Remove the need for an @bdev in filesystem-DAX infrastructure
   - Remove unused uio helpers copy_from_iter_flushcache() and
     copy_mc_to_iter() as only the non-check_copy_size() versions are
     used for DAX.
 - Prepare XFS for the pending (next merge window) DAX+reflink support
 - Remove deprecated DEV_DAX_PMEM_COMPAT support
 - Cleanup a straggling misuse of the GUID api
 
 Tags offered after the branch was cut:
 Reviewed-by: Mike Snitzer <snitzer@redhat.com>
 Link: https://lore.kernel.org/r/Ydb/3P+8nvjCjYfO@redhat.com
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Merge tag 'libnvdimm-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull dax and libnvdimm updates from Dan Williams:
 "The bulk of this is a rework of the dax_operations API after
  discovering the obstacles it posed to the work-in-progress DAX+reflink
  support for XFS and other copy-on-write filesystem mechanics.

  Primarily the need to plumb a block_device through the API to handle
  partition offsets was a sticking point and Christoph untangled that
  dependency in addition to other cleanups to make landing the
  DAX+reflink support easier.

  The DAX_PMEM_COMPAT option has been around for 4 years and not only
  are distributions shipping userspace that understand the current
  configuration API, but some are not even bothering to turn this option
  on anymore, so it seems a good time to remove it per the deprecation
  schedule. Recall that this was added after the device-dax subsystem
  moved from /sys/class/dax to /sys/bus/dax for its sysfs organization.
  All recent functionality depends on /sys/bus/dax.

  Some other miscellaneous cleanups and reflink prep patches are
  included as well.

  Summary:

   - Simplify the dax_operations API:

      - Eliminate bdev_dax_pgoff() in favor of the filesystem
        maintaining and applying a partition offset to all its DAX iomap
        operations.

      - Remove wrappers and device-mapper stacked callbacks for
        ->copy_from_iter() and ->copy_to_iter() in favor of moving
        block_device relative offset responsibility to the
        dax_direct_access() caller.

      - Remove the need for an @bdev in filesystem-DAX infrastructure

      - Remove unused uio helpers copy_from_iter_flushcache() and
        copy_mc_to_iter() as only the non-check_copy_size() versions are
        used for DAX.

   - Prepare XFS for the pending (next merge window) DAX+reflink support

   - Remove deprecated DEV_DAX_PMEM_COMPAT support

   - Cleanup a straggling misuse of the GUID api"

* tag 'libnvdimm-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (38 commits)
  iomap: Fix error handling in iomap_zero_iter()
  ACPI: NFIT: Import GUID before use
  dax: remove the copy_from_iter and copy_to_iter methods
  dax: remove the DAXDEV_F_SYNC flag
  dax: simplify dax_synchronous and set_dax_synchronous
  uio: remove copy_from_iter_flushcache() and copy_mc_to_iter()
  iomap: turn the byte variable in iomap_zero_iter into a ssize_t
  memremap: remove support for external pgmap refcounts
  fsdax: don't require CONFIG_BLOCK
  iomap: build the block based code conditionally
  dax: fix up some of the block device related ifdefs
  fsdax: shift partition offset handling into the file systems
  dax: return the partition offset from fs_dax_get_by_bdev
  iomap: add a IOMAP_DAX flag
  xfs: pass the mapping flags to xfs_bmbt_to_iomap
  xfs: use xfs_direct_write_iomap_ops for DAX zeroing
  xfs: move dax device handling into xfs_{alloc,free}_buftarg
  ext4: cleanup the dax handling in ext4_fill_super
  ext2: cleanup the dax handling in ext2_fill_super
  fsdax: decouple zeroing from the iomap buffered I/O code
  ...
2022-01-12 15:46:11 -08:00
Gao Xiang
09c543798c erofs: use meta buffers for zmap operations
Get rid of old erofs_get_meta_page() within zmap operations by
using on-stack meta buffers in order to prepare subpage and folio
features.

Finally, erofs_get_meta_page() is useless. Get rid of it!

Link: https://lore.kernel.org/r/20220102040017.51352-6-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-01-04 23:47:36 +08:00
Gao Xiang
c521e3ad6c erofs: use meta buffers for inode operations
Get rid of old erofs_get_meta_page() within inode operations by
using on-stack meta buffers in order to prepare subpage and folio
features.

Link: https://lore.kernel.org/r/20220102040017.51352-3-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-01-04 23:44:46 +08:00
Gao Xiang
fdf80a4793 erofs: introduce meta buffer operations
In order to support subpage and folio for all uncompressed files,
introduce meta buffer descriptors, which can be effectively stored
on stack, in place of meta page operations.

This converts the uncompressed data path to meta buffers.

Link: https://lore.kernel.org/r/20220102040017.51352-2-hsiangkao@linux.alibaba.com
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-01-04 23:43:23 +08:00
Yue Hu
ab92184ff8 erofs: add on-disk compressed tail-packing inline support
Introduces erofs compressed tail-packing inline support.

This approach adds a new field called `h_idata_size' in the
per-file compression header to indicate the encoded size of
each tail-packing pcluster.

At runtime, it will find the start logical offset of the tail
pcluster when initializing per-inode zmap and record such
extent (headlcn, idataoff) information to the in-memory inode.
Therefore, follow-on requests can directly recognize if one
pcluster is a tail-packing inline pcluster or not.

Link: https://lore.kernel.org/r/20211228054604.114518-6-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-31 00:51:10 +08:00
Huang Jianan
40452ffca3 erofs: add sysfs node to control sync decompression strategy
Although readpage is a synchronous path, there will be no additional
kworker scheduling overhead in non-atomic contexts together with
dm-verity.

Let's add a sysfs node to disable sync decompression as an option.

Link: https://lore.kernel.org/r/20211206143552.8384-1-huangjianan@oppo.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-08 09:42:18 +08:00
Huang Jianan
168e9a7620 erofs: add sysfs interface
Add sysfs interface to configure erofs related parameters later.

Link: https://lore.kernel.org/r/20211201145436.4357-1-huangjianan@oppo.com
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-08 09:40:37 +08:00
Christoph Hellwig
de20511477 fsdax: shift partition offset handling into the file systems
Remove the last user of ->bdev in dax.c by requiring the file system to
pass in an address that already includes the DAX offset.  As part of the
only set ->bdev or ->daxdev when actually required in the ->iomap_begin
methods.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> [erofs]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-27-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-12-04 08:58:54 -08:00
Christoph Hellwig
cd913c76f4 dax: return the partition offset from fs_dax_get_by_bdev
Prepare for the removal of the block_device from the DAX I/O path by
returning the partition offset from fs_dax_get_by_bdev so that the file
systems have it at hand for use during I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-26-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-12-04 08:58:54 -08:00
Huang Jianan
7e508f2ca8 erofs: rename lz4_0pading to zero_padding
Renaming lz4_0padding to zero_padding globally since LZMA and later
algorithms also need that.

Link: https://lore.kernel.org/r/20211112160935.19394-1-jnhuang95@gmail.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-12-01 21:28:00 +08:00
Gao Xiang
eaa9172ad9 erofs: get rid of ->lru usage
Currently, ->lru is a way to arrange non-LRU pages and has some
in-kernel users. In order to minimize noticable issues of page
reclaim and cache thrashing under high memory presure, limited
temporary pages were all chained with ->lru and can be reused
during the request. However, it seems that ->lru could be removed
when folio is landing.

Let's use page->private to chain temporary pages for now instead
and transform EROFS formally after the topic of the folio / file
page design is finalized.

Link: https://lore.kernel.org/r/20211022090120.14675-1-hsiangkao@linux.alibaba.com
Cc: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-25 08:22:59 +08:00
Gao Xiang
622ceaddb7 erofs: lzma compression support
Add MicroLZMA support in order to maximize compression ratios for
specific scenarios. For example, it's useful for low-end embedded
boards and as a secondary algorithm in a file for specific access
patterns.

MicroLZMA is a new container format for raw LZMA1, which was created
by Lasse Collin aiming to minimize old LZMA headers and get rid of
unnecessary EOPM (end of payload marker) as well as to enable
fixed-sized output compression, especially for 4KiB pclusters.

Similar to LZ4, inplace I/O approach is used to minimize runtime
memory footprint when dealing with I/O. Overlapped decompression is
handled with 1) bounced buffer for data under processing or 2) extra
short-lived pages from the on-stack pagepool which will be shared in
the same read request (128KiB for example).

Link: https://lore.kernel.org/r/20211010213145.17462-8-xiang@kernel.org
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-19 23:44:30 +08:00
Gao Xiang
386292919c erofs: introduce readmore decompression strategy
Previously, the readahead window was strictly followed by EROFS
decompression strategy in order to minimize extra memory footprint.
However, it could become inefficient if just reading the partial
requested data for much big LZ4 pclusters and the upcoming LZMA
implementation.

Let's try to request the leading data in a pcluster without
triggering memory reclaiming instead for the LZ4 approach first
to boost up 100% randread of large big pclusters, and it has no real
impact on low memory scenarios.

It also introduces a way to expand read lengths in order to decompress
the whole pcluster, which is useful for LZMA since the algorithm
itself is relatively slow and causes CPU bound, but LZ4 is not.

Link: https://lore.kernel.org/r/20211008200839.24541-4-xiang@kernel.org
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-19 23:44:30 +08:00
Gao Xiang
8f89926290 erofs: get compression algorithms directly on mapping
Currently, z_erofs_map_blocks_iter() returns whether extents are
compressed or not, and the decompression frontend gets the specific
algorithms then.

It works but not quite well in many aspests, for example:
 - The decompression frontend has to deal with whether extents are
   compressed or not again and lookup the algorithms if compressed.
   It's duplicated and too detailed about the on-disk mapping.

 - A new secondary compression head will be introduced later so that
   each file can have 2 compression algorithms at most for different
   type of data. It could increase the complexity of the decompression
   frontend if still handled in this way;

 - A new readmore decompression strategy will be introduced to get
   better performance for much bigger pcluster and lzma, which needs
   the specific algorithm in advance as well.

Let's look up compression algorithms in z_erofs_map_blocks_iter()
directly instead.

Link: https://lore.kernel.org/r/20211008200839.24541-2-xiang@kernel.org
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-18 00:15:55 +08:00
Gao Xiang
dfeab2e95a erofs: add multiple device support
In order to support multi-layer container images, add multiple
device feature to EROFS. Two ways are available to use for now:

 - Devices can be mapped into 32-bit global block address space;
 - Device ID can be specified with the chunk indexes format.

Note that it assumes no extent would cross device boundary and mkfs
should take care of it seriously.

In the future, a dedicated device manager could be introduced then
thus extra devices can be automatically scanned by UUID as well.

Link: https://lore.kernel.org/r/20211014081010.43485-1-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-10-18 00:13:30 +08:00