From: Karel Zak <kzak@redhat.com>
Date: Tue, 3 Jul 2018 11:51:51 +0000 (+0200)
Subject: fallocate: add man page note about --collapse-range granularity
X-Git-Tag: v2.33-rc1~149
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=562adaed911db581fe01664c07a27184e27087c3;p=thirdparty%2Futil-linux.git

fallocate: add man page note about --collapse-range granularity

Reported-by: Radka Skvarilova <rskvaril@redhat.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/sys-utils/fallocate.1 b/sys-utils/fallocate.1
index d4821dcd17..fe5072ae86 100644
--- a/sys-utils/fallocate.1
+++ b/sys-utils/fallocate.1
@@ -72,6 +72,12 @@ The option
 may not be specified for the collapse-range operation.
 .sp
 Available since Linux 3.15 for ext4 (only for extent-based files) and XFS.
+.sp
+A filesystem may place limitations on the granularity of the operation, in
+order to ensure efficient implementation.  Typically, offset and len 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 if this requirement is violated.
 .TP
 .BR \-d ", " \-\-dig\-holes
 Detect and dig holes.
diff --git a/sys-utils/fallocate.c b/sys-utils/fallocate.c
index c6bed63ef7..c97e63d4b3 100644
--- a/sys-utils/fallocate.c
+++ b/sys-utils/fallocate.c
@@ -121,6 +121,9 @@ static loff_t cvtnum(char *s)
 static void xfallocate(int fd, int mode, off_t offset, off_t length)
 {
 	int error;
+
+fprintf(stderr, "KZAK>>> %d\n", mode);
+
 #ifdef HAVE_FALLOCATE
 	error = fallocate(fd, mode, offset, length);
 #else