freebsd-nq/sys/fs/specfs/spec_vnops.c
1998-09-12 20:21:54 +00:00

938 lines
22 KiB
C

/*
* Copyright (c) 1989, 1993, 1995
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* 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
* SUCH DAMAGE.
*
* @(#)spec_vnops.c 8.14 (Berkeley) 5/21/95
* $Id: spec_vnops.c,v 1.73 1998/09/05 14:13:12 phk Exp $
*/
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/buf.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/stat.h>
#include <sys/fcntl.h>
#include <sys/disklabel.h>
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/vm_prot.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/vnode_pager.h>
#include <vm/vm_extern.h>
#include <miscfs/specfs/specdev.h>
static int spec_advlock __P((struct vop_advlock_args *));
static int spec_badop __P((void));
static int spec_bmap __P((struct vop_bmap_args *));
static int spec_close __P((struct vop_close_args *));
static int spec_freeblks __P((struct vop_freeblks_args *));
static int spec_fsync __P((struct vop_fsync_args *));
static int spec_getattr __P((struct vop_getattr_args *));
static int spec_getpages __P((struct vop_getpages_args *));
static int spec_inactive __P((struct vop_inactive_args *));
static int spec_ioctl __P((struct vop_ioctl_args *));
static int spec_lookup __P((struct vop_lookup_args *));
static int spec_open __P((struct vop_open_args *));
static int spec_poll __P((struct vop_poll_args *));
static int spec_print __P((struct vop_print_args *));
static int spec_read __P((struct vop_read_args *));
static int spec_strategy __P((struct vop_strategy_args *));
static int spec_write __P((struct vop_write_args *));
struct vnode *speclisth[SPECHSZ];
vop_t **spec_vnodeop_p;
static struct vnodeopv_entry_desc spec_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *) vop_defaultop },
{ &vop_access_desc, (vop_t *) vop_ebadf },
{ &vop_advlock_desc, (vop_t *) spec_advlock },
{ &vop_bmap_desc, (vop_t *) spec_bmap },
{ &vop_close_desc, (vop_t *) spec_close },
{ &vop_create_desc, (vop_t *) spec_badop },
{ &vop_freeblks_desc, (vop_t *) spec_freeblks },
{ &vop_fsync_desc, (vop_t *) spec_fsync },
{ &vop_getattr_desc, (vop_t *) spec_getattr },
{ &vop_getpages_desc, (vop_t *) spec_getpages },
{ &vop_inactive_desc, (vop_t *) spec_inactive },
{ &vop_ioctl_desc, (vop_t *) spec_ioctl },
{ &vop_lease_desc, (vop_t *) vop_null },
{ &vop_link_desc, (vop_t *) spec_badop },
{ &vop_lookup_desc, (vop_t *) spec_lookup },
{ &vop_mkdir_desc, (vop_t *) spec_badop },
{ &vop_mknod_desc, (vop_t *) spec_badop },
{ &vop_open_desc, (vop_t *) spec_open },
{ &vop_pathconf_desc, (vop_t *) vop_stdpathconf },
{ &vop_poll_desc, (vop_t *) spec_poll },
{ &vop_print_desc, (vop_t *) spec_print },
{ &vop_read_desc, (vop_t *) spec_read },
{ &vop_readdir_desc, (vop_t *) spec_badop },
{ &vop_readlink_desc, (vop_t *) spec_badop },
{ &vop_reallocblks_desc, (vop_t *) spec_badop },
{ &vop_reclaim_desc, (vop_t *) vop_null },
{ &vop_remove_desc, (vop_t *) spec_badop },
{ &vop_rename_desc, (vop_t *) spec_badop },
{ &vop_rmdir_desc, (vop_t *) spec_badop },
{ &vop_setattr_desc, (vop_t *) vop_ebadf },
{ &vop_strategy_desc, (vop_t *) spec_strategy },
{ &vop_symlink_desc, (vop_t *) spec_badop },
{ &vop_write_desc, (vop_t *) spec_write },
{ NULL, NULL }
};
static struct vnodeopv_desc spec_vnodeop_opv_desc =
{ &spec_vnodeop_p, spec_vnodeop_entries };
VNODEOP_SET(spec_vnodeop_opv_desc);
int
spec_vnoperate(ap)
struct vop_generic_args /* {
struct vnodeop_desc *a_desc;
<other random data follows, presumably>
} */ *ap;
{
return (VOCALL(spec_vnodeop_p, ap->a_desc->vdesc_offset, ap));
}
static void spec_getpages_iodone __P((struct buf *bp));
/*
* Trivial lookup routine that always fails.
*/
static int
spec_lookup(ap)
struct vop_lookup_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
} */ *ap;
{
*ap->a_vpp = NULL;
return (ENOTDIR);
}
/*
* Open a special file.
*/
/* ARGSUSED */
static int
spec_open(ap)
struct vop_open_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct proc *p = ap->a_p;
struct vnode *bvp, *vp = ap->a_vp;
dev_t bdev, dev = (dev_t)vp->v_rdev;
int maj = major(dev);
int error;
/*
* Don't allow open if fs is mounted -nodev.
*/
if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
return (ENXIO);
switch (vp->v_type) {
case VCHR:
if ((u_int)maj >= nchrdev)
return (ENXIO);
if ( (cdevsw[maj] == NULL) || (cdevsw[maj]->d_open == NULL))
return ENXIO;
if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) {
/*
* When running in very secure mode, do not allow
* opens for writing of any disk character devices.
*/
if (securelevel >= 2
&& cdevsw[maj]->d_bmaj != -1
&& (cdevsw[maj]->d_flags & D_TYPEMASK) == D_DISK)
return (EPERM);
/*
* When running in secure mode, do not allow opens
* for writing of /dev/mem, /dev/kmem, or character
* devices whose corresponding block devices are
* currently mounted.
*/
if (securelevel >= 1) {
if ((bdev = chrtoblk(dev)) != NODEV &&
vfinddev(bdev, VBLK, &bvp) &&
bvp->v_usecount > 0 &&
(error = vfs_mountedon(bvp)))
return (error);
if (iskmemdev(dev))
return (EPERM);
}
}
if ((cdevsw[maj]->d_flags & D_TYPEMASK) == D_TTY)
vp->v_flag |= VISTTY;
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[maj]->d_open)(dev, ap->a_mode, S_IFCHR, p);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if ((u_int)maj >= nblkdev)
return (ENXIO);
if ( (bdevsw[maj] == NULL) || (bdevsw[maj]->d_open == NULL))
return ENXIO;
/*
* When running in very secure mode, do not allow
* opens for writing of any disk block devices.
*/
if (securelevel >= 2 && ap->a_cred != FSCRED &&
(ap->a_mode & FWRITE) &&
(bdevsw[maj]->d_flags & D_TYPEMASK) == D_DISK)
return (EPERM);
/*
* Do not allow opens of block devices that are
* currently mounted.
*/
error = vfs_mountedon(vp);
if (error)
return (error);
return ((*bdevsw[maj]->d_open)(dev, ap->a_mode, S_IFBLK, p));
}
return (0);
}
/*
* Vnode op for read
*/
/* ARGSUSED */
static int
spec_read(ap)
struct vop_read_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct uio *uio = ap->a_uio;
struct proc *p = uio->uio_procp;
struct buf *bp;
daddr_t bn, nextbn;
long bsize, bscale;
struct partinfo dpart;
int n, on, majordev;
d_ioctl_t *ioctl;
int error = 0;
dev_t dev;
#ifdef DIAGNOSTIC
if (uio->uio_rw != UIO_READ)
panic("spec_read mode");
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
panic("spec_read proc");
#endif
if (uio->uio_resid == 0)
return (0);
switch (vp->v_type) {
case VCHR:
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[major(vp->v_rdev)]->d_read)
(vp->v_rdev, uio, ap->a_ioflag);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if (uio->uio_offset < 0)
return (EINVAL);
bsize = BLKDEV_IOSIZE;
dev = vp->v_rdev;
if ((majordev = major(dev)) < nblkdev &&
(ioctl = bdevsw[majordev]->d_ioctl) != NULL &&
(*ioctl)(dev, DIOCGPART, (caddr_t)&dpart, FREAD, p) == 0 &&
dpart.part->p_fstype == FS_BSDFFS &&
dpart.part->p_frag != 0 && dpart.part->p_fsize != 0)
bsize = dpart.part->p_frag * dpart.part->p_fsize;
bscale = btodb(bsize);
do {
bn = btodb(uio->uio_offset) & ~(bscale - 1);
on = uio->uio_offset % bsize;
n = min((unsigned)(bsize - on), uio->uio_resid);
if (vp->v_lastr + bscale == bn) {
nextbn = bn + bscale;
error = breadn(vp, bn, (int)bsize, &nextbn,
(int *)&bsize, 1, NOCRED, &bp);
} else
error = bread(vp, bn, (int)bsize, NOCRED, &bp);
vp->v_lastr = bn;
n = min(n, bsize - bp->b_resid);
if (error) {
brelse(bp);
return (error);
}
error = uiomove((char *)bp->b_data + on, n, uio);
brelse(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
return (error);
default:
panic("spec_read type");
}
/* NOTREACHED */
}
/*
* Vnode op for write
*/
/* ARGSUSED */
static int
spec_write(ap)
struct vop_write_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct uio *uio = ap->a_uio;
struct proc *p = uio->uio_procp;
struct buf *bp;
daddr_t bn;
int bsize, blkmask;
struct partinfo dpart;
register int n, on;
int error = 0;
#ifdef DIAGNOSTIC
if (uio->uio_rw != UIO_WRITE)
panic("spec_write mode");
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
panic("spec_write proc");
#endif
switch (vp->v_type) {
case VCHR:
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[major(vp->v_rdev)]->d_write)
(vp->v_rdev, uio, ap->a_ioflag);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if (uio->uio_resid == 0)
return (0);
if (uio->uio_offset < 0)
return (EINVAL);
bsize = BLKDEV_IOSIZE;
if ((*bdevsw[major(vp->v_rdev)]->d_ioctl)(vp->v_rdev, DIOCGPART,
(caddr_t)&dpart, FREAD, p) == 0) {
if (dpart.part->p_fstype == FS_BSDFFS &&
dpart.part->p_frag != 0 && dpart.part->p_fsize != 0)
bsize = dpart.part->p_frag *
dpart.part->p_fsize;
}
blkmask = btodb(bsize) - 1;
do {
bn = btodb(uio->uio_offset) & ~blkmask;
on = uio->uio_offset % bsize;
n = min((unsigned)(bsize - on), uio->uio_resid);
if (n == bsize)
bp = getblk(vp, bn, bsize, 0, 0);
else
error = bread(vp, bn, bsize, NOCRED, &bp);
n = min(n, bsize - bp->b_resid);
if (error) {
brelse(bp);
return (error);
}
error = uiomove((char *)bp->b_data + on, n, uio);
if (n + on == bsize)
bawrite(bp);
else
bdwrite(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
return (error);
default:
panic("spec_write type");
}
/* NOTREACHED */
}
/*
* Device ioctl operation.
*/
/* ARGSUSED */
static int
spec_ioctl(ap)
struct vop_ioctl_args /* {
struct vnode *a_vp;
int a_command;
caddr_t a_data;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
dev_t dev = ap->a_vp->v_rdev;
switch (ap->a_vp->v_type) {
case VCHR:
return ((*cdevsw[major(dev)]->d_ioctl)(dev, ap->a_command,
ap->a_data, ap->a_fflag, ap->a_p));
case VBLK:
return ((*bdevsw[major(dev)]->d_ioctl)(dev, ap->a_command,
ap->a_data, ap->a_fflag, ap->a_p));
default:
panic("spec_ioctl");
/* NOTREACHED */
}
}
/* ARGSUSED */
static int
spec_poll(ap)
struct vop_poll_args /* {
struct vnode *a_vp;
int a_events;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
register dev_t dev;
switch (ap->a_vp->v_type) {
case VCHR:
dev = ap->a_vp->v_rdev;
return (*cdevsw[major(dev)]->d_poll)(dev, ap->a_events, ap->a_p);
default:
return (vop_defaultop((struct vop_generic_args *)ap));
}
}
/*
* Synch buffers associated with a block device
*/
/* ARGSUSED */
static int
spec_fsync(ap)
struct vop_fsync_args /* {
struct vnode *a_vp;
struct ucred *a_cred;
int a_waitfor;
struct proc *a_p;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct buf *bp;
struct buf *nbp;
int s;
if (vp->v_type == VCHR)
return (0);
/*
* Flush all dirty buffers associated with a block device.
*/
loop:
s = splbio();
for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
nbp = bp->b_vnbufs.le_next;
if ((bp->b_flags & B_BUSY))
continue;
if ((bp->b_flags & B_DELWRI) == 0)
panic("spec_fsync: not dirty");
if ((vp->v_flag & VOBJBUF) && (bp->b_flags & B_CLUSTEROK)) {
vfs_bio_awrite(bp);
splx(s);
} else {
bremfree(bp);
bp->b_flags |= B_BUSY;
splx(s);
bawrite(bp);
}
goto loop;
}
if (ap->a_waitfor == MNT_WAIT) {
while (vp->v_numoutput) {
vp->v_flag |= VBWAIT;
(void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spfsyn", 0);
}
#ifdef DIAGNOSTIC
if (vp->v_dirtyblkhd.lh_first) {
vprint("spec_fsync: dirty", vp);
splx(s);
goto loop;
}
#endif
}
splx(s);
return (0);
}
static int
spec_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
struct proc *a_p;
} */ *ap;
{
VOP_UNLOCK(ap->a_vp, 0, ap->a_p);
return (0);
}
/*
* Just call the device strategy routine
*/
static int
spec_strategy(ap)
struct vop_strategy_args /* {
struct buf *a_bp;
} */ *ap;
{
struct buf *bp;
bp = ap->a_bp;
if (((bp->b_flags & B_READ) == 0) &&
(LIST_FIRST(&bp->b_dep)) != NULL && bioops.io_start)
(*bioops.io_start)(bp);
(*bdevsw[major(bp->b_dev)]->d_strategy)(bp);
return (0);
}
static int
spec_freeblks(ap)
struct vop_freeblks_args /* {
struct vnode *a_vp;
daddr_t a_addr;
daddr_t a_length;
} */ *ap;
{
struct cdevsw *bsw;
struct buf *bp;
bsw = bdevsw[major(ap->a_vp->v_rdev)];
if ((bsw->d_flags & D_CANFREE) == 0)
return (0);
bp = geteblk(ap->a_length);
bp->b_flags |= B_FREEBUF | B_BUSY;
bp->b_dev = ap->a_vp->v_rdev;
bp->b_blkno = ap->a_addr;
bp->b_offset = dbtob(ap->a_addr);
bp->b_bcount = ap->a_length;
(*bsw->d_strategy)(bp);
return (0);
}
/*
* This is a noop, simply returning what one has been given.
*/
static int
spec_bmap(ap)
struct vop_bmap_args /* {
struct vnode *a_vp;
daddr_t a_bn;
struct vnode **a_vpp;
daddr_t *a_bnp;
int *a_runp;
int *a_runb;
} */ *ap;
{
if (ap->a_vpp != NULL)
*ap->a_vpp = ap->a_vp;
if (ap->a_bnp != NULL)
*ap->a_bnp = ap->a_bn;
if (ap->a_runp != NULL)
*ap->a_runp = 0;
if (ap->a_runb != NULL)
*ap->a_runb = 0;
return (0);
}
/*
* Device close routine
*/
/* ARGSUSED */
static int
spec_close(ap)
struct vop_close_args /* {
struct vnode *a_vp;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
struct proc *p = ap->a_p;
dev_t dev = vp->v_rdev;
d_close_t *devclose;
int mode, error;
switch (vp->v_type) {
case VCHR:
/*
* Hack: a tty device that is a controlling terminal
* has a reference from the session structure.
* We cannot easily tell that a character device is
* a controlling terminal, unless it is the closing
* process' controlling terminal. In that case,
* if the reference count is 2 (this last descriptor
* plus the session), release the reference from the session.
*/
if (vcount(vp) == 2 && ap->a_p &&
(vp->v_flag & VXLOCK) == 0 &&
vp == ap->a_p->p_session->s_ttyvp) {
vrele(vp);
ap->a_p->p_session->s_ttyvp = NULL;
}
/*
* If the vnode is locked, then we are in the midst
* of forcably closing the device, otherwise we only
* close on last reference.
*/
if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
return (0);
devclose = cdevsw[major(dev)]->d_close;
mode = S_IFCHR;
break;
case VBLK:
/*
* On last close of a block device (that isn't mounted)
* we must invalidate any in core blocks, so that
* we can, for instance, change floppy disks.
*/
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, ap->a_p);
error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0);
VOP_UNLOCK(vp, 0, ap->a_p);
if (error)
return (error);
/*
* We do not want to really close the device if it
* is still in use unless we are trying to close it
* forcibly. Since every use (buffer, vnode, swap, cmap)
* holds a reference to the vnode, and because we mark
* any other vnodes that alias this device, when the
* sum of the reference counts on all the aliased
* vnodes descends to one, we are on last close.
*/
if ((vcount(vp) > 1) && (vp->v_flag & VXLOCK) == 0)
return (0);
devclose = bdevsw[major(dev)]->d_close;
mode = S_IFBLK;
break;
default:
panic("spec_close: not special");
}
return ((*devclose)(dev, ap->a_fflag, mode, ap->a_p));
}
/*
* Print out the contents of a special device vnode.
*/
static int
spec_print(ap)
struct vop_print_args /* {
struct vnode *a_vp;
} */ *ap;
{
printf("tag VT_NON, dev %d, %d\n", major(ap->a_vp->v_rdev),
minor(ap->a_vp->v_rdev));
return (0);
}
/*
* Special device advisory byte-level locks.
*/
/* ARGSUSED */
static int
spec_advlock(ap)
struct vop_advlock_args /* {
struct vnode *a_vp;
caddr_t a_id;
int a_op;
struct flock *a_fl;
int a_flags;
} */ *ap;
{
return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL);
}
/*
* Special device bad operation
*/
static int
spec_badop()
{
panic("spec_badop called");
/* NOTREACHED */
}
static void
spec_getpages_iodone(bp)
struct buf *bp;
{
bp->b_flags |= B_DONE;
wakeup(bp);
}
static int
spec_getpages(ap)
struct vop_getpages_args *ap;
{
vm_offset_t kva;
int error;
int i, pcount, size, s;
daddr_t blkno;
struct buf *bp;
vm_page_t m;
vm_ooffset_t offset;
int toff, nextoff, nread;
struct vnode *vp = ap->a_vp;
int blksiz;
int gotreqpage;
error = 0;
pcount = round_page(ap->a_count) / PAGE_SIZE;
/*
* Calculate the offset of the transfer.
*/
offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset;
/* XXX sanity check before we go into details. */
/* XXX limits should be defined elsewhere. */
#define DADDR_T_BIT 32
#define OFFSET_MAX ((1LL << (DADDR_T_BIT + DEV_BSHIFT)) - 1)
if (offset < 0 || offset > OFFSET_MAX) {
/* XXX still no %q in kernel. */
printf("spec_getpages: preposterous offset 0x%x%08x\n",
(u_int)((u_quad_t)offset >> 32),
(u_int)(offset & 0xffffffff));
return (VM_PAGER_ERROR);
}
blkno = btodb(offset);
/*
* Round up physical size for real devices, use the
* fundamental blocksize of the fs if possible.
*/
if (vp && vp->v_mount) {
if (vp->v_type != VBLK) {
vprint("Non VBLK", vp);
}
blksiz = vp->v_mount->mnt_stat.f_bsize;
if (blksiz < DEV_BSIZE) {
blksiz = DEV_BSIZE;
}
}
else
blksiz = DEV_BSIZE;
size = (ap->a_count + blksiz - 1) & ~(blksiz - 1);
bp = getpbuf();
kva = (vm_offset_t)bp->b_data;
/*
* Map the pages to be read into the kva.
*/
pmap_qenter(kva, ap->a_m, pcount);
/* Build a minimal buffer header. */
bp->b_flags = B_BUSY | B_READ | B_CALL;
bp->b_iodone = spec_getpages_iodone;
/* B_PHYS is not set, but it is nice to fill this in. */
bp->b_proc = curproc;
bp->b_rcred = bp->b_wcred = bp->b_proc->p_ucred;
if (bp->b_rcred != NOCRED)
crhold(bp->b_rcred);
if (bp->b_wcred != NOCRED)
crhold(bp->b_wcred);
bp->b_blkno = blkno;
bp->b_lblkno = blkno;
pbgetvp(ap->a_vp, bp);
bp->b_bcount = size;
bp->b_bufsize = size;
bp->b_resid = 0;
cnt.v_vnodein++;
cnt.v_vnodepgsin += pcount;
/* Do the input. */
VOP_STRATEGY(bp->b_vp, bp);
s = splbio();
/* We definitely need to be at splbio here. */
while ((bp->b_flags & B_DONE) == 0)
tsleep(bp, PVM, "spread", 0);
splx(s);
if ((bp->b_flags & B_ERROR) != 0) {
if (bp->b_error)
error = bp->b_error;
else
error = EIO;
}
nread = size - bp->b_resid;
if (nread < ap->a_count) {
bzero((caddr_t)kva + nread,
ap->a_count - nread);
}
pmap_qremove(kva, pcount);
gotreqpage = 0;
for (i = 0, toff = 0; i < pcount; i++, toff = nextoff) {
nextoff = toff + PAGE_SIZE;
m = ap->a_m[i];
m->flags &= ~PG_ZERO;
if (nextoff <= nread) {
m->valid = VM_PAGE_BITS_ALL;
m->dirty = 0;
} else if (toff < nread) {
int nvalid = ((nread + DEV_BSIZE - 1) - toff) & ~(DEV_BSIZE - 1);
vm_page_set_validclean(m, 0, nvalid);
} else {
m->valid = 0;
m->dirty = 0;
}
if (i != ap->a_reqpage) {
/*
* Just in case someone was asking for this page we
* now tell them that it is ok to use.
*/
if (!error || (m->valid == VM_PAGE_BITS_ALL)) {
if (m->valid) {
if (m->flags & PG_WANTED) {
vm_page_activate(m);
} else {
vm_page_deactivate(m);
}
vm_page_wakeup(m);
} else {
vm_page_free(m);
}
} else {
vm_page_free(m);
}
} else if (m->valid) {
gotreqpage = 1;
}
}
if (!gotreqpage) {
m = ap->a_m[ap->a_reqpage];
#ifndef MAX_PERF
printf(
"spec_getpages: I/O read failure: (error code=%d)\n",
error);
printf(
" size: %d, resid: %ld, a_count: %d, valid: 0x%x\n",
size, bp->b_resid, ap->a_count, m->valid);
printf(
" nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n",
nread, ap->a_reqpage, (u_long)m->pindex, pcount);
#endif
/*
* Free the buffer header back to the swap buffer pool.
*/
relpbuf(bp);
return VM_PAGER_ERROR;
}
/*
* Free the buffer header back to the swap buffer pool.
*/
relpbuf(bp);
return VM_PAGER_OK;
}
/* ARGSUSED */
static int
spec_getattr(ap)
struct vop_getattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct vattr *vap = ap->a_vap;
struct partinfo dpart;
bzero(vap, sizeof (*vap));
if (vp->v_type == VBLK)
vap->va_blocksize = BLKDEV_IOSIZE;
else if (vp->v_type == VCHR)
vap->va_blocksize = MAXBSIZE;
if ((*bdevsw[major(vp->v_rdev)]->d_ioctl)(vp->v_rdev, DIOCGPART,
(caddr_t)&dpart, FREAD, ap->a_p) == 0) {
vap->va_bytes = dbtob(dpart.disklab->d_partitions
[minor(vp->v_rdev)].p_size);
vap->va_size = vap->va_bytes;
}
return (0);
}