incfs.rst 2.7 KB

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