Differential D28833 Diff 86185 lib/libc/sys/fspacectl.2

Changeset View

Standalone View

lib/libc/sys/fspacectl.2

Show All 18 Lines
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL		.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS		.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)		.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT		.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY		.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF		.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.		.\" SUCH DAMAGE.
.\"		.\"
.Dd Feb 08, 2021		.Dd February 8, 2021
.Dt FSPACECTL 2		.Dt FSPACECTL 2
.Os		.Os
.Sh NAME		.Sh NAME
.Nm fspacectl		.Nm fspacectl
.Nd space management in a file		.Nd space management in a file
.Sh LIBRARY		.Sh LIBRARY
.Lb libc		.Lb libc
.Sh SYNOPSIS		.Sh SYNOPSIS
Show All 20 Lines	struct spacectl_range {
off_t r_len;		off_t r_len;
};		};
.Ed		.Ed
.Pp		.Pp
The operation specified by the		The operation specified by the
.Fa cmd		.Fa cmd
argument may be one of:		argument may be one of:
.Bl -tag -width SPACECTL_DEALLOC		.Bl -tag -width SPACECTL_DEALLOC
		.It Dv SPACECTL_ALLOC
		Back a region in the file specified by the
		.Fa range
		argument within the file system space.
		gbeUnsubmitted Done Inline Actions ...argument within the file system space. gbe: ...argument within the file system space.
		Subsequent operations in the region will not fail due to lack of free space in
		the file system.
		This operation is used to implement
		gbeUnsubmitted Done Inline Actions ...for a non-hole region. gbe: ...for a non-hole region.
		.Xr posix_fallocate 2 .
		Content will remain the same for a non-hole region.
		Holes will be converted to non-hole region with zeroes.
.It Dv SPACECTL_DEALLOC		.It Dv SPACECTL_DEALLOC
Zero a region in the file specified by the		Zero a region in the file specified by the
.Fa range		.Fa range
argument.		argument.
If the file system supports hole-punching,		If the file system supports hole-punching,
file system space deallocation may be performed in the given region.		file system space deallocation may be performed in the given region.
.El		.El
.Pp		.Pp
The		The
.Fa flags		.Fa flags
argument needs be the value 0 currently.		argument may include one or more of the following:
		.Bl -tag -width SPACECTL_F_CANEXTEND
		.It Dv SPACECTL_F_CANEXTEND
		The operation can extend the file size if
		.Fa range->r_offset
		+
		.Fa range->r_len
		is greater than the current file size.
		This flag is supported by the
		.Dv SPACECTL_ALLOC
		operation.
		.El
.Pp		.Pp
If signal is delivered to a thread calling this system call,		If signal is delivered to a thread calling this system call,
the system call would either finish as if nothing has happened,		the system call would either finish as if nothing has happened,
or signal would be delivered after the operation finishes.		or signal would be delivered after the operation finishes.
.Sh RETURN VALUES		.Sh RETURN VALUES
Upon successful completion, the value 0 is returned;		Upon successful completion, the value 0 is returned;
otherwise the value -1 is returned and		otherwise the value -1 is returned and
.Va errno		.Va errno
▲ Show 20 Lines • Show All 65 Lines • Show Last 20 Lines