Thank you for your review comments! On 2025/8/15 0:52, Darrick J. Wong wrote: > On Wed, Aug 13, 2025 at 10:40:15AM +0800, Zhang Yi wrote: >> From: Zhang Yi <yi.zh...@huawei.com> >> >> The Linux kernel (since version 6.17) supports FALLOC_FL_WRITE_ZEROES in >> fallocate(2). Add support for FALLOC_FL_WRITE_ZEROES to the fallocate >> utility by introducing a new option -w|--write-zeroes. >> >> Link: >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=278c7d9b5e0c >> Signed-off-by: Zhang Yi <yi.zh...@huawei.com> >> --- >> v1->v2: >> - Minor description modification to align with the kernel. >> >> sys-utils/fallocate.1.adoc | 11 +++++++++-- >> sys-utils/fallocate.c | 20 ++++++++++++++++---- >> 2 files changed, 25 insertions(+), 6 deletions(-) >> >> diff --git a/sys-utils/fallocate.1.adoc b/sys-utils/fallocate.1.adoc >> index 44ee0ef4c..0ec9ff9a9 100644 >> --- a/sys-utils/fallocate.1.adoc >> +++ b/sys-utils/fallocate.1.adoc >> @@ -12,7 +12,7 @@ fallocate - preallocate or deallocate space to a file > > <snip all the long lines> > >> +*-w*, *--write-zeroes*:: >> +Zeroes space in the byte range starting at _offset_ and continuing >> for _length_ bytes. Within the specified range, blocks are >> preallocated for the regions that span the holes in the file. After a >> successful call, subsequent reads from this range will return zeroes, >> subsequent writes to that range do not require further changes to the >> file mapping metadata. > > "...will return zeroes and subsequent writes to that range..." ? >
Yeah. >> ++ >> +Zeroing is done within the filesystem by preferably submitting write > > I think we should say less about what the filesystem actually does to > preserve some flexibility: > > "Zeroing is done within the filesystem. The filesystem may use a > hardware accelerated zeroing command, or it may submit regular writes. > The behavior depends on the filesystem design and available hardware." > Sure. >> zeores commands, the alternative way is submitting actual zeroed data, >> the specified range will be converted into written extents. The write >> zeroes command is typically faster than write actual data if the >> device supports unmap write zeroes, the specified range will not be >> physically zeroed out on the device. >> ++ >> +Options *--keep-size* can not be specified for the write-zeroes >> operation. >> + >> include::man-common/help-version.adoc[] >> >> == AUTHORS [..] >> @@ -429,6 +438,9 @@ int main(int argc, char **argv) >> else if (mode & FALLOC_FL_ZERO_RANGE) >> fprintf(stdout, _("%s: %s (%ju bytes) >> zeroed.\n"), >> filename, str, >> length); >> + else if (mode & FALLOC_FL_WRITE_ZEROES) >> + fprintf(stdout, _("%s: %s (%ju bytes) write >> zeroed.\n"), > > "write zeroed" is a little strange, but I don't have a better > suggestion. :) > Hmm... What about simply using "zeroed", the same to FALLOC_FL_ZERO_RANGE? Users should be aware of the parameters they have passed to fallocate(), so they should not use this print for further differentiation. Thanks, Yi.