1.. SPDX-License-Identifier: GPL-2.0 2 3================================================= 4incfs: A stacked incremental filesystem for Linux 5================================================= 6 7/sys/fs interface 8================= 9 10Please update Documentation/ABI/testing/sysfs-fs-incfs if you update this 11section. 12 13incfs creates the following files in /sys/fs. 14 15Features 16-------- 17 18/sys/fs/incremental-fs/features/corefs 19 Reads 'supported'. Always present. 20 21/sys/fs/incremental-fs/features/v2 22 Reads 'supported'. Present if all v2 features of incfs are supported. These 23 are: 24 fs-verity support 25 inotify support 26 ioclts: 27 INCFS_IOC_SET_READ_TIMEOUTS 28 INCFS_IOC_GET_READ_TIMEOUTS 29 INCFS_IOC_GET_BLOCK_COUNT 30 INCFS_IOC_CREATE_MAPPED_FILE 31 .incomplete folder 32 .blocks_written pseudo file 33 report_uid mount option 34 35/sys/fs/incremental-fs/features/zstd 36 Reads 'supported'. Present if zstd compression is supported for data blocks. 37 38Optional per mount 39------------------ 40 41For each incfs mount, the mount option sysfs_name=[name] creates a /sys/fs 42node called: 43 44/sys/fs/incremental-fs/instances/[name] 45 46This will contain the following files: 47 48/sys/fs/incremental-fs/instances/[name]/reads_delayed_min 49 Returns a count of the number of reads that were delayed as a result of the 50 per UID read timeouts min time setting. 51 52/sys/fs/incremental-fs/instances/[name]/reads_delayed_min_us 53 Returns total delay time for all files since first mount as a result of the 54 per UID read timeouts min time setting. 55 56/sys/fs/incremental-fs/instances/[name]/reads_delayed_pending 57 Returns a count of the number of reads that were delayed as a result of 58 waiting for a pending read. 59 60/sys/fs/incremental-fs/instances/[name]/reads_delayed_pending_us 61 Returns total delay time for all files since first mount as a result of 62 waiting for a pending read. 63 64/sys/fs/incremental-fs/instances/[name]/reads_failed_hash_verification 65 Returns number of reads that failed because of hash verification failures. 66 67/sys/fs/incremental-fs/instances/[name]/reads_failed_other 68 Returns number of reads that failed for reasons other than timing out or 69 hash failures. 70 71/sys/fs/incremental-fs/instances/[name]/reads_failed_timed_out 72 Returns number of reads that timed out. 73 74For reads_delayed_*** settings, note that a file can count for both 75reads_delayed_min and reads_delayed_pending if incfs first waits for a pending 76read then has to wait further for the min time. In that case, the time spent 77waiting is split between reads_delayed_pending_us, which is increased by the 78time spent waiting for the pending read, and reads_delayed_min_us, which is 79increased by the remainder of the time spent waiting. 80 81Reads that timed out are not added to the reads_delayed_pending or the 82reads_delayed_pending_us counters. 83