1.\"- 2.\" SPDX-License-Identifier: BSD-2-Clause 3.\" 4.\" Copyright (c) 2019 The FreeBSD Foundation 5.\" 6.\" This documentation was written by BFF Storage Systems, LLC under 7.\" sponsorship from the FreeBSD Foundation. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" $FreeBSD$ 31.\" 32.Dd June 19, 2019 33.Dt VOP_BMAP 9 34.Os 35.Sh NAME 36.Nm VOP_BMAP 37.Nd Logical to physical block number conversion 38.Sh SYNOPSIS 39.In sys/param.h 40.In sys/vnode.h 41.Ft int 42.Fn VOP_BMAP "struct vnode *vp" "daddr_t bn" "struct bufobj **bop" "daddr_t *bnp" "int *runp" "int *runb" 43.Sh DESCRIPTION 44This vnode call is used to lookup the physical block number of the file system's 45underlying device where a given logical block of a file is stored. 46Its arguments are: 47.Bl -tag -width type 48.It Fa vp 49The vnode of the file. 50.It Fa bn 51Logical block number within the file identified by 52.Fa vp . 53.It Fa bop 54Return storage for the buffer object associated with the file system's 55underlying device. 56.It Fa bnp 57Return storage for the physical block number. 58.It Fa runp 59Return storage for the number of succeeding logical blocks that may be 60efficiently read at the same time as the requested block. 61This will usually be the number of logical blocks whose physical blocks are 62contiguously allocated. 63However a file system is free to define "efficient" as it see fit. 64.It Fa runb 65Like 66.Fa runp 67but for preceding rather than succeeding blocks. 68.El 69.Pp 70Any of the return arguments may be 71.Dv NULL 72to indicate that the caller does not care about that information. 73.Sh LOCKS 74The vnode will be locked on entry and should remain locked on return. 75.Sh RETURN VALUES 76Zero is returned on success, otherwise an error code is returned. 77.Sh SEE ALSO 78.Xr vnode 9 79.Sh HISTORY 80A 81.Fn bmap 82function first appeared in 83.Bx 4.2 . 84.Sh AUTHORS 85This manual page was written by 86.An Alan Somers . 87