Documentation/ABI/testing/sysfs-fs-erofs

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-fs-erofs

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-fs-erofs
Extension
[no extension]
Size
1882 bytes
Lines
50
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

What:		/sys/fs/erofs/features/
Date:		November 2021
Contact:	"Huang Jianan" <huangjianan@oppo.com>
Description:	Shows all enabled kernel features.
		Supported features:
		compr_cfgs, big_pcluster, chunked_file, device_table,
		compr_head2, sb_chksum, ztailpacking, dedupe, fragments,
		48bit, metabox.

What:		/sys/fs/erofs/<disk>/sync_decompress
Date:		November 2021
Contact:	"Huang Jianan" <huangjianan@oppo.com>
Description:	Control strategy of synchronous decompression. Synchronous
		decompression tries to decompress in the reader thread for
		synchronous reads and small asynchronous reads (<= 12 KiB):

		- 0 (auto, default): apply to synchronous reads only, but will
		                     switch to 1 (force on) if any decompression
		                     request is detected in atomic contexts;
		- 1 (force on): apply to synchronous reads and small
		                asynchronous reads;
		- 2 (force off): disable synchronous decompression completely.

What:		/sys/fs/erofs/<disk>/drop_caches
Date:		November 2024
Contact:	"Guo Chunhai" <guochunhai@vivo.com>
Description:	Writing to this will drop compression-related caches,
		currently used to drop in-memory pclusters and cached
		compressed folios:

		- 1 : invalidate cached compressed folios
		- 2 : drop in-memory pclusters
		- 3 : drop in-memory pclusters and cached compressed folios

What:		/sys/fs/erofs/accel
Date:		May 2025
Contact:	"Bo Liu" <liubo03@inspur.com>
Description:	Used to set or show hardware accelerators in effect
		and multiple accelerators are separated by '\n'.
		Supported accelerator(s): qat_deflate.
		Disable all accelerators with an empty string (echo > accel).

What:		/sys/fs/erofs/<disk>/dir_ra_bytes
Date:		July 2025
Contact:	"Chao Yu" <chao@kernel.org>
Description:	Used to set or show readahead bytes during readdir(), by
		default the value is 16384.

		- 0: disable readahead.

Annotation

Implementation Notes