xref: /freebsd/share/man/man9/VOP_DEALLOCATE.9 (revision 2faf504d1ab821fe2b9df9d2afb49bb35e1334f4)
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30.Dd August 11, 2021
31.Dt VOP_DEALLOCATE 9
32.Os
33.Sh NAME
34.Nm VOP_DEALLOCATE
35.Nd zero and/or deallocate storage from a file
36.Sh SYNOPSIS
37.In sys/param.h
38.In sys/vnode.h
39.Ft int
40.Fo VOP_DEALLOCATE
41.Fa "struct vnode *vp"
42.Fa "off_t *offset"
43.Fa "off_t *len"
44.Fa "int flags"
45.Fa "int ioflag"
46.Fa "struct ucred *cred"
47.Fc
48.Sh DESCRIPTION
49This VOP call zeroes/deallocates storage for an offset range in a file.
50It is used to implement the
51.Xr fspacectl 2
52system call.
53.Pp
54Its arguments are:
55.Bl -tag -width offset
56.It Fa vp
57The vnode of the file.
58.It Fa offset
59The start of the range to deallocate storage in the file.
60.It Fa len
61The length of the range to deallocate storage in the file.
62.It Fa flags
63The flags of this call.
64This should be set to 0 for now.
65.It Fa ioflag
66Directives and hints to be given to the file system.
67.It Fa cred
68The credentials of the caller.
69.El
70.Pp
71.Fa *offset
72and
73.Fa *len
74are updated to reflect the portion of the range that
75still needs to be zeroed/deallocated on return.
76Partial result is considered a successful operation.
77.Sh LOCKS
78The vnode should be locked on entry and will still be locked on exit.
79.Sh RETURN VALUES
80Zero is returned if the call is successful, otherwise an appropriate
81error code is returned.
82.Sh ERRORS
83.Bl -tag -width Er
84.It Bq Er EINVAL
85Invalid
86.Fa offset , len
87or
88.Fa flags
89parameters are passed into this VOP call.
90.It Bq Er ENODEV
91The vnode type is not supported by this VOP call.
92.It Bq Er ENOSPC
93The file system is full.
94.It Bq Er EPERM
95An append-only flag is set on the file, but the caller is attempting to
96zero before the current end of file.
97.El
98.Sh SEE ALSO
99.Xr vnode 9
100.Sh AUTHORS
101.Nm
102and this manual page was written by
103.An Ka Ho Ng Aq Mt khng@FreeBSD.org
104under sponsorship from the FreeBSD Foundation.
105