mirror_zfs/module
Tony Hutter 00d85a98ea BRT: Fix FICLONE/FICLONERANGE shortened copy
On Linux the ioctl_ficlonerange() and ioctl_ficlone() system calls
are expected to either fully clone the specified range or return an
error.  The range may be for an entire file.  While internally ZFS
supports cloning partial ranges there's no way to return the length
cloned to the caller so we need to make this all or nothing.

As part of this change support for the REMAP_FILE_CAN_SHORTEN flag
has been added.  When REMAP_FILE_CAN_SHORTEN is set zfs_clone_range()
will return a shortened range when encountering pending dirty records.
When it's clear zfs_clone_range() will block and wait for the records
to be written out allowing the blocks to be cloned.

Furthermore, the file range lock is held over the region being cloned
to prevent it from being modified while cloning.  This doesn't quite
provide an atomic semantics since if an error is encountered only a
portion of the range may be cloned.  This will be converted to an
error if REMAP_FILE_CAN_SHORTEN was not provided and returned to the
caller.  However, the destination file range is left in an undefined
state.

A test case has been added which exercises this functionality by
verifying that `cp --reflink=never|auto|always` works correctly.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #15728
Closes #15842
2024-02-06 10:01:15 -08:00
..
avl Suppress Clang Static Analyzer false positive in the AVL tree code. 2023-03-08 13:51:21 -08:00
icp Add BTI landing pads to the AArch64 SHA2 assembly 2023-10-04 12:36:21 -07:00
lua Add loongarch64 support 2023-04-25 16:05:45 -07:00
nvpair nvpair: Constify string functions 2023-03-14 15:25:50 -07:00
os BRT: Fix FICLONE/FICLONERANGE shortened copy 2024-02-06 10:01:15 -08:00
unicode Illumos #15286: do_composition() needs sign awareness 2023-01-05 11:16:21 -08:00
zcommon set autotrim default to 'off' everywhere 2023-07-21 16:35:12 -07:00
zfs BRT: Fix FICLONE/FICLONERANGE shortened copy 2024-02-06 10:01:15 -08:00
zstd Resolve WS-2021-0184 vulnerability in zstd 2023-02-02 15:12:51 -08:00
.gitignore FreeBSD: Ignore symlink to i386 includes 2022-08-02 16:34:23 -07:00
Kbuild.in linux 6.7 compat: rework shrinker setup for heap allocations 2023-12-21 11:03:08 -08:00
Makefile.bsd Finally drop long disabled vdev cache. 2023-06-09 12:40:55 -07:00
Makefile.in check-zstd-symbols: also ignore __pfx_ symbols 2023-09-19 08:52:06 -07:00