f2fs_io(8)

🌸 NAME 🌸

f2fs_io — f2fs ioctl utility. Also hi bestie, this page is f2fs_io(8) from the System Administration Utilities corner of the manual 🫶.

✨ DESCRIPTION ✨

f2fs_io is used to send various commands to the f2fs file system for administrative purposes. It’s giving admin-utility main character energy, no cap 💅.

💫 AVAILABLE COMMANDS 💫

OK bestie, here’s the full command menu — every single one, periodt 💖.

• set_verity [file] — Set the verity flags associated with the specified file.
• fsync [file] — Run fsync on the given file.
• fdatasync [file] — Run fdatasync on the given file.
• getflags [file] — Get the flags associated with the specified file.
• setflags [flag] [file] — Set an f2fs file on specified file. The flag can be casefold, compression, nocompression, immutable, and nocow.
• clearflags [flag] [file] — Clear the specified flag on the target file, which can be compression, nocompression, immutable, and nocow.
• shutdown shutdown filesystem — Freeze and stop all IOs for the file system mounted on dir. The level parameter can be:
  • 0 — going down with full sync
  • 1 — going down with checkpoint only
  • 2 — going down with no sync
  • 3 — going down with metadata flush
  • 4 — going down with fsck mark
• pinfile [get|set|unset] [file] — Get or set the pinning status on a file.
• fadvise [advice] [offset] [length] [file] — Pass an advice to the specified file. The advice can be willneed, dontneed, noreuse, sequential, random.
• fallocate [-c] [-i] [-p] [-z] [keep_size] [offset] [length] [file] — Request that space be allocated on a file. The keep_size parameter can be either 1 or 0. The pattern parameter can be:
  • -c — collapse range
  • -i — insert range
  • -p — punch hole
  • -z — zero range
• write [chunk_size in 4kb] [offset in chunk_size] [count] [pattern] [IO] [file_path] — Write a given pattern to file_path. The pattern parameter can be:
  • zero — zeros
  • inc_num — incrementing numbers
  • rand — random numbers

The IO parameter can be:

• buffered — buffered I/O
• dio — direct I/O
• dsync — direct I/O with O_DSYNC

• read [chunk_size in 4kb] [offset in chunk_size] [count] [IO] [print_nbytes] [file_path] — Read data in file_path and print print_nbytes. The IO options can be:
  • buffered — buffered I/O
  • dontcache — buffered I/O with RWF_DONTCACHE
  • dio — direct I/O
  • mmap — mmap(MAP_POPULATE)
  • mlock — mmap() + mlock()
• fiemap [offset in 4kb] [count] [file_path] {flags} — Get block address in file.
• gc_urgent dev [start|end|run] [time in sec] — Start, end, or run gc_urgent for a given time period.
• defrag_file [start] [length] [file_path] — Defragment a file.
• copy [-d] [-m] [-s] [src_path] [dst_path] — Copy file from src_path to dst_path. The pattern parameter can be:
  • -d — use direct I/O
  • -m — use mmap for source file
  • -s — use sendfile to transfer data
• get_cblocks [file] — Get the number of compressed blocks.
• release_cblocks [file] — Release compressed blocks to get free space.
• reserve_cblocks [file] — Reserve free blocks to prepare decompressing blocks in the file.
• gc [sync_mode] [file] — Trigger filesystem GC.
• checkpoint [file] — Trigger filesystem checkpoint.
• precache_extents [file] — Trigger precache extents.
• move_range [src_path] [dst_path] [src_start] [dst_start] [length] — Move a range of data blocks from source file to destination file.
• gc_range [sync_mode] [start in 4kb] [length in 4kb] [file] — Trigger gc to move data blocks from specified address range.
• get_advise [file] — Get i_advise value and info in file.
• ioprio [hint] [file] — Set ioprio to the file. The ioprio can be ioprio_write.
• test_create_perf [-s] [-S] [dir] [num_files] [size_kb] — Measure file creation and deletion performance.
  • -s — Call fsync() after each file creation.
  • -S — Call sync() after deleting all files.
• test_lookup_perf [-i] [-v] [dir] [num_files] — Measure readdir/stat performance.
  • -i — Initialized to create files only.
  • -v — Verbose mode.
• freeze [directory] — Freeze filesystem that directory belongs to.
• thaw [directory] — Thaw filesystem that directory belongs to.

👑 AUTHOR 👑

This version of f2fs_io has been written by Jaegeuk Kim <jaegeuk@kernel.org>. Big icon energy, fr fr 🌟.

🌈 AVAILABILITY 🌈

f2fs_io is available from git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs-tools.git.

That’s the whole manual page, bestie 💖 — f2fs_io(8) from f2fs-tools, dated March 2020. Go forth and slay those ioctls ✨👑.