787 lines
19 KiB
C
787 lines
19 KiB
C
/*
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* Copyright (c) 1988 University of Utah.
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* Copyright (c) 1990, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* the Systems Programming Group of the University of Utah Computer
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* Science Department.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* from: Utah Hdr: vn.c 1.13 94/04/02
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*
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* from: @(#)vn.c 8.6 (Berkeley) 4/1/94
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* $FreeBSD$
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*/
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/*
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* Vnode disk driver.
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*
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* Block/character interface to a vnode. Allows one to treat a file
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* as a disk (e.g. build a filesystem in it, mount it, etc.).
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*
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* NOTE 1: This uses the VOP_BMAP/VOP_STRATEGY interface to the vnode
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* instead of a simple VOP_RDWR. We do this to avoid distorting the
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* local buffer cache.
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*
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* NOTE 2: There is a security issue involved with this driver.
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* Once mounted all access to the contents of the "mapped" file via
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* the special file is controlled by the permissions on the special
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* file, the protection of the mapped file is ignored (effectively,
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* by using root credentials in all transactions).
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*
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* NOTE 3: Doesn't interact with leases, should it?
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/namei.h>
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#include <sys/proc.h>
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#include <sys/bio.h>
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#include <sys/malloc.h>
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#include <sys/mount.h>
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#include <sys/vnode.h>
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#include <sys/fcntl.h>
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#include <sys/conf.h>
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#include <sys/disklabel.h>
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#include <sys/diskslice.h>
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#include <sys/stat.h>
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#include <sys/conf.h>
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#include <sys/module.h>
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#include <sys/vnioctl.h>
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#include <vm/vm.h>
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#include <vm/vm_object.h>
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#include <vm/vm_page.h>
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#include <vm/vm_pager.h>
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#include <vm/vm_pageout.h>
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#include <vm/swap_pager.h>
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#include <vm/vm_extern.h>
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static d_ioctl_t vnioctl;
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static d_open_t vnopen;
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static d_close_t vnclose;
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static d_psize_t vnsize;
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static d_strategy_t vnstrategy;
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#define CDEV_MAJOR 43
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#define BDEV_MAJOR 15
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#define VN_BSIZE_BEST 8192
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/*
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* cdevsw
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* D_DISK we want to look like a disk
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* D_CANFREE We support BIO_DELETE
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*/
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static struct cdevsw vn_cdevsw = {
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/* open */ vnopen,
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/* close */ vnclose,
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/* read */ physread,
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/* write */ physwrite,
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/* ioctl */ vnioctl,
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/* poll */ nopoll,
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/* mmap */ nommap,
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/* strategy */ vnstrategy,
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/* name */ "vn",
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/* maj */ CDEV_MAJOR,
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/* dump */ nodump,
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/* psize */ vnsize,
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/* flags */ D_DISK|D_CANFREE,
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/* bmaj */ BDEV_MAJOR
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};
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#define getvnbuf() \
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((struct buf *)malloc(sizeof(struct buf), M_DEVBUF, M_WAITOK))
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#define putvnbuf(bp) \
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free((caddr_t)(bp), M_DEVBUF)
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struct vn_softc {
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int sc_unit;
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int sc_flags; /* flags */
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int sc_size; /* size of vn, sc_secsize scale */
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int sc_secsize; /* sector size */
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struct diskslices *sc_slices;
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struct vnode *sc_vp; /* vnode if not NULL */
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vm_object_t sc_object; /* backing object if not NULL */
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struct ucred *sc_cred; /* credentials */
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int sc_maxactive; /* max # of active requests */
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u_long sc_options; /* options */
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SLIST_ENTRY(vn_softc) sc_list;
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};
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static SLIST_HEAD(, vn_softc) vn_list;
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/* sc_flags */
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#define VNF_INITED 0x01
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#define VNF_READONLY 0x02
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static u_long vn_options;
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#define IFOPT(vn,opt) if (((vn)->sc_options|vn_options) & (opt))
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#define TESTOPT(vn,opt) (((vn)->sc_options|vn_options) & (opt))
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static int vnsetcred (struct vn_softc *vn, struct ucred *cred);
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static void vnclear (struct vn_softc *vn);
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static int vn_modevent (module_t, int, void *);
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static int vniocattach_file (struct vn_softc *, struct vn_ioctl *, dev_t dev, int flag, struct proc *p);
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static int vniocattach_swap (struct vn_softc *, struct vn_ioctl *, dev_t dev, int flag, struct proc *p);
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static int
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vnclose(dev_t dev, int flags, int mode, struct proc *p)
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{
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struct vn_softc *vn = dev->si_drv1;
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IFOPT(vn, VN_LABELS)
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if (vn->sc_slices != NULL)
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dsclose(dev, mode, vn->sc_slices);
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return (0);
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}
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static struct vn_softc *
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vnfindvn(dev_t dev)
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{
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int unit;
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struct vn_softc *vn;
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unit = dkunit(dev);
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vn = dev->si_drv1;
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if (!vn) {
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SLIST_FOREACH(vn, &vn_list, sc_list) {
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if (vn->sc_unit == unit) {
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dev->si_drv1 = vn;
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break;
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}
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}
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}
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if (!vn) {
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vn = malloc(sizeof *vn, M_DEVBUF, M_WAITOK);
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if (!vn)
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return (NULL);
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bzero(vn, sizeof *vn);
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vn->sc_unit = unit;
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dev->si_drv1 = vn;
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make_dev(&vn_cdevsw, 0,
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UID_ROOT, GID_OPERATOR, 0640, "vn%d", unit);
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SLIST_INSERT_HEAD(&vn_list, vn, sc_list);
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}
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return (vn);
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}
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static int
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vnopen(dev_t dev, int flags, int mode, struct proc *p)
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{
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struct vn_softc *vn;
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/*
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* Locate preexisting device
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*/
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if ((vn = dev->si_drv1) == NULL)
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vn = vnfindvn(dev);
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/*
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* Update si_bsize fields for device. This data will be overriden by
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* the slice/parition code for vn accesses through partitions, and
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* used directly if you open the 'whole disk' device.
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*
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* si_bsize_best must be reinitialized in case VN has been
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* reconfigured, plus make it at least VN_BSIZE_BEST for efficiency.
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*/
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dev->si_bsize_phys = vn->sc_secsize;
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dev->si_bsize_best = vn->sc_secsize;
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if (dev->si_bsize_best < VN_BSIZE_BEST)
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dev->si_bsize_best = VN_BSIZE_BEST;
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if ((flags & FWRITE) && (vn->sc_flags & VNF_READONLY))
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return (EACCES);
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IFOPT(vn, VN_FOLLOW)
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printf("vnopen(%s, 0x%x, 0x%x, %p)\n",
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devtoname(dev), flags, mode, (void *)p);
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/*
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* Initialize label
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*/
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IFOPT(vn, VN_LABELS) {
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if (vn->sc_flags & VNF_INITED) {
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struct disklabel label;
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/* Build label for whole disk. */
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bzero(&label, sizeof label);
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label.d_secsize = vn->sc_secsize;
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label.d_nsectors = 32;
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label.d_ntracks = 64 / (vn->sc_secsize / DEV_BSIZE);
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label.d_secpercyl = label.d_nsectors * label.d_ntracks;
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label.d_ncylinders = vn->sc_size / label.d_secpercyl;
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label.d_secperunit = vn->sc_size;
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label.d_partitions[RAW_PART].p_size = vn->sc_size;
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return (dsopen(dev, mode, 0, &vn->sc_slices, &label));
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}
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if (dkslice(dev) != WHOLE_DISK_SLICE ||
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dkpart(dev) != RAW_PART ||
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mode != S_IFCHR) {
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return (ENXIO);
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}
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}
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return(0);
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}
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/*
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* vnstrategy:
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*
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* Run strategy routine for VN device. We use VOP_READ/VOP_WRITE calls
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* for vnode-backed vn's, and the new vm_pager_strategy() call for
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* vm_object-backed vn's.
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*
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* NOTE: bp->b_blkno is DEV_BSIZE'd. We must generate bp->b_pblkno for
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* our uio or vn_pager_strategy() call that is vn->sc_secsize'd
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*/
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static void
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vnstrategy(struct bio *bp)
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{
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int unit;
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struct vn_softc *vn;
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int error;
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int isvplocked = 0;
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unit = dkunit(bp->bio_dev);
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vn = bp->bio_dev->si_drv1;
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if (vn == NULL)
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vn = vnfindvn(bp->bio_dev);
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IFOPT(vn, VN_DEBUG)
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printf("vnstrategy(%p): unit %d\n", bp, unit);
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if ((vn->sc_flags & VNF_INITED) == 0) {
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bp->bio_error = ENXIO;
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bp->bio_flags |= BIO_ERROR;
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biodone(bp);
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return;
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}
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bp->bio_resid = bp->bio_bcount;
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IFOPT(vn, VN_LABELS) {
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if (vn->sc_slices != NULL && dscheck(bp, vn->sc_slices) <= 0) {
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bp->bio_error = EINVAL;
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bp->bio_flags |= BIO_ERROR;
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biodone(bp);
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return;
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}
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} else {
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int pbn; /* in sc_secsize chunks */
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long sz; /* in sc_secsize chunks */
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/*
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* Check for required alignment. Transfers must be a valid
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* multiple of the sector size.
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*/
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if (bp->bio_bcount % vn->sc_secsize != 0 ||
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bp->bio_blkno % (vn->sc_secsize / DEV_BSIZE) != 0) {
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bp->bio_error = EINVAL;
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bp->bio_flags |= BIO_ERROR;
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biodone(bp);
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return;
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}
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pbn = bp->bio_blkno / (vn->sc_secsize / DEV_BSIZE);
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sz = howmany(bp->bio_bcount, vn->sc_secsize);
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/*
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* If out of bounds return an error. If at the EOF point,
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* simply read or write less.
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*/
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if (pbn < 0 || pbn >= vn->sc_size) {
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if (pbn != vn->sc_size) {
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bp->bio_error = EINVAL;
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/* XXX bp->b_flags |= B_INVAL; */
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bp->bio_flags |= BIO_ERROR;
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}
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biodone(bp);
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return;
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}
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/*
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* If the request crosses EOF, truncate the request.
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*/
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if (pbn + sz > vn->sc_size) {
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bp->bio_bcount = (vn->sc_size - pbn) * vn->sc_secsize;
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bp->bio_resid = bp->bio_bcount;
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}
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bp->bio_pblkno = pbn;
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}
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if (vn->sc_vp && (bp->bio_cmd == BIO_DELETE)) {
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/*
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* Not handled for vnode-backed element yet.
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*/
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biodone(bp);
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} else if (vn->sc_vp) {
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/*
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* VNODE I/O
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*
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* If an error occurs, we set BIO_ERROR but we do not set
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* B_INVAL because (for a write anyway), the buffer is
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* still valid.
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*/
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struct uio auio;
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struct iovec aiov;
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bzero(&auio, sizeof(auio));
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aiov.iov_base = bp->bio_data;
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aiov.iov_len = bp->bio_bcount;
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auio.uio_iov = &aiov;
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auio.uio_iovcnt = 1;
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auio.uio_offset = (vm_ooffset_t)bp->bio_pblkno * vn->sc_secsize;
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auio.uio_segflg = UIO_SYSSPACE;
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if(bp->bio_cmd == BIO_READ)
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auio.uio_rw = UIO_READ;
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else
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auio.uio_rw = UIO_WRITE;
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auio.uio_resid = bp->bio_bcount;
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auio.uio_procp = curproc;
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if (!VOP_ISLOCKED(vn->sc_vp, NULL)) {
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isvplocked = 1;
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vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
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}
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if(bp->bio_cmd == BIO_READ)
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error = VOP_READ(vn->sc_vp, &auio, 0, vn->sc_cred);
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else
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error = VOP_WRITE(vn->sc_vp, &auio, 0, vn->sc_cred);
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if (isvplocked) {
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VOP_UNLOCK(vn->sc_vp, 0, curproc);
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isvplocked = 0;
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}
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bp->bio_resid = auio.uio_resid;
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if (error) {
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bp->bio_error = error;
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bp->bio_flags |= BIO_ERROR;
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}
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biodone(bp);
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} else if (vn->sc_object) {
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/*
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* OBJT_SWAP I/O
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*
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* ( handles read, write, freebuf )
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*
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* Note: if we pre-reserved swap, BIO_DELETE is disabled
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*/
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#if 0
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KASSERT((bp->b_bufsize & (vn->sc_secsize - 1)) == 0,
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("vnstrategy: buffer %p too small for physio", bp));
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#endif
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if ((bp->bio_cmd == BIO_DELETE) && TESTOPT(vn, VN_RESERVE)) {
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biodone(bp);
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} else {
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vm_pager_strategy(vn->sc_object, bp);
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}
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} else {
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bp->bio_flags |= BIO_ERROR;
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bp->bio_error = EINVAL;
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biodone(bp);
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}
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}
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|
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/* ARGSUSED */
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static int
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vnioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
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{
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struct vn_softc *vn;
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struct vn_ioctl *vio;
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int error;
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u_long *f;
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vn = dev->si_drv1;
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IFOPT(vn,VN_FOLLOW)
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printf("vnioctl(%s, 0x%lx, %p, 0x%x, %p): unit %d\n",
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devtoname(dev), cmd, (void *)data, flag, (void *)p,
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dkunit(dev));
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switch (cmd) {
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case VNIOCATTACH:
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case VNIOCDETACH:
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case VNIOCGSET:
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case VNIOCGCLEAR:
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case VNIOCUSET:
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case VNIOCUCLEAR:
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goto vn_specific;
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}
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IFOPT(vn,VN_LABELS) {
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if (vn->sc_slices != NULL) {
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error = dsioctl(dev, cmd, data, flag, &vn->sc_slices);
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if (error != ENOIOCTL)
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return (error);
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}
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if (dkslice(dev) != WHOLE_DISK_SLICE ||
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dkpart(dev) != RAW_PART)
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return (ENOTTY);
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}
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vn_specific:
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error = suser(p);
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if (error)
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return (error);
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vio = (struct vn_ioctl *)data;
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f = (u_long*)data;
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switch (cmd) {
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case VNIOCATTACH:
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if (vn->sc_flags & VNF_INITED)
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return(EBUSY);
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if (vio->vn_file == NULL)
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error = vniocattach_swap(vn, vio, dev, flag, p);
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else
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error = vniocattach_file(vn, vio, dev, flag, p);
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break;
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case VNIOCDETACH:
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if ((vn->sc_flags & VNF_INITED) == 0)
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return(ENXIO);
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/*
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* XXX handle i/o in progress. Return EBUSY, or wait, or
|
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* flush the i/o.
|
|
* XXX handle multiple opens of the device. Return EBUSY,
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|
* or revoke the fd's.
|
|
* How are these problems handled for removable and failing
|
|
* hardware devices? (Hint: They are not)
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|
*/
|
|
vnclear(vn);
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IFOPT(vn, VN_FOLLOW)
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printf("vnioctl: CLRed\n");
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break;
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|
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case VNIOCGSET:
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vn_options |= *f;
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*f = vn_options;
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break;
|
|
|
|
case VNIOCGCLEAR:
|
|
vn_options &= ~(*f);
|
|
*f = vn_options;
|
|
break;
|
|
|
|
case VNIOCUSET:
|
|
vn->sc_options |= *f;
|
|
*f = vn->sc_options;
|
|
break;
|
|
|
|
case VNIOCUCLEAR:
|
|
vn->sc_options &= ~(*f);
|
|
*f = vn->sc_options;
|
|
break;
|
|
|
|
default:
|
|
error = ENOTTY;
|
|
break;
|
|
}
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* vniocattach_file:
|
|
*
|
|
* Attach a file to a VN partition. Return the size in the vn_size
|
|
* field.
|
|
*/
|
|
|
|
static int
|
|
vniocattach_file(vn, vio, dev, flag, p)
|
|
struct vn_softc *vn;
|
|
struct vn_ioctl *vio;
|
|
dev_t dev;
|
|
int flag;
|
|
struct proc *p;
|
|
{
|
|
struct vattr vattr;
|
|
struct nameidata nd;
|
|
int error, flags;
|
|
|
|
flags = FREAD|FWRITE;
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vn_file, p);
|
|
error = vn_open(&nd, flags, 0);
|
|
if (error) {
|
|
if (error != EACCES && error != EPERM && error != EROFS)
|
|
return (error);
|
|
flags &= ~FWRITE;
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vn_file, p);
|
|
error = vn_open(&nd, flags, 0);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
NDFREE(&nd, NDF_ONLY_PNBUF);
|
|
if (nd.ni_vp->v_type != VREG ||
|
|
(error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p))) {
|
|
VOP_UNLOCK(nd.ni_vp, 0, p);
|
|
(void) vn_close(nd.ni_vp, flags, p->p_ucred, p);
|
|
return (error ? error : EINVAL);
|
|
}
|
|
VOP_UNLOCK(nd.ni_vp, 0, p);
|
|
vn->sc_secsize = DEV_BSIZE;
|
|
vn->sc_vp = nd.ni_vp;
|
|
|
|
/*
|
|
* If the size is specified, override the file attributes. Note that
|
|
* the vn_size argument is in PAGE_SIZE sized blocks.
|
|
*/
|
|
if (vio->vn_size)
|
|
vn->sc_size = (quad_t)vio->vn_size * PAGE_SIZE / vn->sc_secsize;
|
|
else
|
|
vn->sc_size = vattr.va_size / vn->sc_secsize;
|
|
error = vnsetcred(vn, p->p_ucred);
|
|
if (error) {
|
|
(void) vn_close(nd.ni_vp, flags, p->p_ucred, p);
|
|
return(error);
|
|
}
|
|
vn->sc_flags |= VNF_INITED;
|
|
if (flags == FREAD)
|
|
vn->sc_flags |= VNF_READONLY;
|
|
IFOPT(vn, VN_LABELS) {
|
|
/*
|
|
* Reopen so that `ds' knows which devices are open.
|
|
* If this is the first VNIOCSET, then we've
|
|
* guaranteed that the device is the cdev and that
|
|
* no other slices or labels are open. Otherwise,
|
|
* we rely on VNIOCCLR not being abused.
|
|
*/
|
|
error = vnopen(dev, flag, S_IFCHR, p);
|
|
if (error)
|
|
vnclear(vn);
|
|
}
|
|
IFOPT(vn, VN_FOLLOW)
|
|
printf("vnioctl: SET vp %p size %x blks\n",
|
|
vn->sc_vp, vn->sc_size);
|
|
return(0);
|
|
}
|
|
|
|
/*
|
|
* vniocattach_swap:
|
|
*
|
|
* Attach swap backing store to a VN partition of the size specified
|
|
* in vn_size.
|
|
*/
|
|
|
|
static int
|
|
vniocattach_swap(vn, vio, dev, flag, p)
|
|
struct vn_softc *vn;
|
|
struct vn_ioctl *vio;
|
|
dev_t dev;
|
|
int flag;
|
|
struct proc *p;
|
|
{
|
|
int error;
|
|
|
|
/*
|
|
* Range check. Disallow negative sizes or any size less then the
|
|
* size of a page. Then round to a page.
|
|
*/
|
|
|
|
if (vio->vn_size <= 0)
|
|
return(EDOM);
|
|
|
|
/*
|
|
* Allocate an OBJT_SWAP object.
|
|
*
|
|
* sc_secsize is PAGE_SIZE'd
|
|
*
|
|
* vio->vn_size is in PAGE_SIZE'd chunks.
|
|
* sc_size must be in PAGE_SIZE'd chunks.
|
|
* Note the truncation.
|
|
*/
|
|
|
|
vn->sc_secsize = PAGE_SIZE;
|
|
vn->sc_size = vio->vn_size;
|
|
vn->sc_object =
|
|
vm_pager_allocate(OBJT_SWAP, NULL, vn->sc_secsize * (vm_ooffset_t)vio->vn_size, VM_PROT_DEFAULT, 0);
|
|
IFOPT(vn, VN_RESERVE) {
|
|
if (swap_pager_reserve(vn->sc_object, 0, vn->sc_size) < 0) {
|
|
vm_pager_deallocate(vn->sc_object);
|
|
vn->sc_object = NULL;
|
|
return(EDOM);
|
|
}
|
|
}
|
|
vn->sc_flags |= VNF_INITED;
|
|
|
|
error = vnsetcred(vn, p->p_ucred);
|
|
if (error == 0) {
|
|
IFOPT(vn, VN_LABELS) {
|
|
/*
|
|
* Reopen so that `ds' knows which devices are open.
|
|
* If this is the first VNIOCSET, then we've
|
|
* guaranteed that the device is the cdev and that
|
|
* no other slices or labels are open. Otherwise,
|
|
* we rely on VNIOCCLR not being abused.
|
|
*/
|
|
error = vnopen(dev, flag, S_IFCHR, p);
|
|
}
|
|
}
|
|
if (error == 0) {
|
|
IFOPT(vn, VN_FOLLOW) {
|
|
printf("vnioctl: SET vp %p size %x\n",
|
|
vn->sc_vp, vn->sc_size);
|
|
}
|
|
}
|
|
if (error)
|
|
vnclear(vn);
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* Duplicate the current processes' credentials. Since we are called only
|
|
* as the result of a SET ioctl and only root can do that, any future access
|
|
* to this "disk" is essentially as root. Note that credentials may change
|
|
* if some other uid can write directly to the mapped file (NFS).
|
|
*/
|
|
int
|
|
vnsetcred(struct vn_softc *vn, struct ucred *cred)
|
|
{
|
|
char *tmpbuf;
|
|
int error = 0;
|
|
|
|
/*
|
|
* Set credits in our softc
|
|
*/
|
|
|
|
if (vn->sc_cred)
|
|
crfree(vn->sc_cred);
|
|
vn->sc_cred = crdup(cred);
|
|
|
|
/*
|
|
* Horrible kludge to establish credentials for NFS XXX.
|
|
*/
|
|
|
|
if (vn->sc_vp) {
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
|
|
tmpbuf = malloc(vn->sc_secsize, M_TEMP, M_WAITOK);
|
|
bzero(&auio, sizeof(auio));
|
|
|
|
aiov.iov_base = tmpbuf;
|
|
aiov.iov_len = vn->sc_secsize;
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_offset = 0;
|
|
auio.uio_rw = UIO_READ;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_resid = aiov.iov_len;
|
|
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
|
|
error = VOP_READ(vn->sc_vp, &auio, 0, vn->sc_cred);
|
|
VOP_UNLOCK(vn->sc_vp, 0, curproc);
|
|
free(tmpbuf, M_TEMP);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
void
|
|
vnclear(struct vn_softc *vn)
|
|
{
|
|
struct proc *p = curproc; /* XXX */
|
|
|
|
IFOPT(vn, VN_FOLLOW)
|
|
printf("vnclear(%p): vp=%p\n", vn, vn->sc_vp);
|
|
if (vn->sc_slices != NULL)
|
|
dsgone(&vn->sc_slices);
|
|
vn->sc_flags &= ~VNF_INITED;
|
|
if (vn->sc_vp != NULL) {
|
|
(void)vn_close(vn->sc_vp, vn->sc_flags & VNF_READONLY ?
|
|
FREAD : (FREAD|FWRITE), vn->sc_cred, p);
|
|
vn->sc_vp = NULL;
|
|
}
|
|
vn->sc_flags &= ~VNF_READONLY;
|
|
if (vn->sc_cred) {
|
|
crfree(vn->sc_cred);
|
|
vn->sc_cred = NULL;
|
|
}
|
|
if (vn->sc_object != NULL) {
|
|
vm_pager_deallocate(vn->sc_object);
|
|
vn->sc_object = NULL;
|
|
}
|
|
vn->sc_size = 0;
|
|
}
|
|
|
|
static int
|
|
vnsize(dev_t dev)
|
|
{
|
|
struct vn_softc *vn;
|
|
|
|
vn = dev->si_drv1;
|
|
if (!vn)
|
|
return(-1);
|
|
if ((vn->sc_flags & VNF_INITED) == 0)
|
|
return(-1);
|
|
|
|
return(vn->sc_size);
|
|
}
|
|
|
|
static int
|
|
vn_modevent(module_t mod, int type, void *data)
|
|
{
|
|
struct vn_softc *vn;
|
|
|
|
switch (type) {
|
|
case MOD_LOAD:
|
|
cdevsw_add(&vn_cdevsw);
|
|
break;
|
|
|
|
case MOD_UNLOAD:
|
|
/* fall through */
|
|
case MOD_SHUTDOWN:
|
|
for (;;) {
|
|
vn = SLIST_FIRST(&vn_list);
|
|
if (!vn)
|
|
break;
|
|
SLIST_REMOVE_HEAD(&vn_list, sc_list);
|
|
if (vn->sc_flags & VNF_INITED)
|
|
vnclear(vn);
|
|
free(vn, M_DEVBUF);
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
DEV_MODULE(vn, vn_modevent, 0);
|