From b2db5a71b5c37dea3f1d5780664fdce317389d18 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Mon, 4 Jan 2021 10:50:24 +0100 Subject: [PATCH] fallocate: (man) add hint about off/len limitations Signed-off-by: Karel Zak --- sys-utils/fallocate.1 | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/sys-utils/fallocate.1 b/sys-utils/fallocate.1 index 9e214c7362..cabc41fdb1 100644 --- a/sys-utils/fallocate.1 +++ b/sys-utils/fallocate.1 @@ -33,6 +33,17 @@ preallocation is done quickly by allocating blocks and marking them as uninitialized, requiring no IO to the data blocks. This is much faster than creating a file by filling it with zeroes. .PP +.PP +Note that a filesystem may place limitations on the granularity of some +fallocate operations. Typically, +.I offset +and +.I lenght +must be a multiple of the +filesystem logical block size, which varies according to the filesystem type +and configuration. If a filesystem has such a requirement, the operation will +fail with the error EINVAL (Invalid argument) if this requirement is violated. +.PP The exit status returned by .B fallocate is 0 on success and 1 on failure. -- 2.47.3