+++ /dev/null
-/*
- * 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
- * $FreeBSD: src/sys/miscfs/specfs/spec_vnops.c,v 1.131.2.4 2001/02/26 04:23:20 jlemon Exp $
- * $DragonFly: src/sys/vfs/specfs/spec_vnops.c,v 1.58 2008/05/06 00:14:12 dillon 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/device.h>
-#include <sys/mount.h>
-#include <sys/vnode.h>
-#include <sys/stat.h>
-#include <sys/fcntl.h>
-#include <sys/vmmeter.h>
-#include <sys/bus.h>
-#include <sys/tty.h>
-
-#include <vm/vm.h>
-#include <vm/vm_object.h>
-#include <vm/vm_page.h>
-#include <vm/vm_pager.h>
-
-#include <machine/limits.h>
-
-#include <sys/buf2.h>
-
-#include <sys/thread2.h>
-
-/*
- * Specfs chained debugging (bitmask)
- *
- * 0 - disable debugging
- * 1 - report chained I/Os
- * 2 - force 4K chained I/Os
- */
-#define SPEC_CHAIN_DEBUG 0
-
-static int spec_advlock (struct vop_advlock_args *);
-static int spec_bmap (struct vop_bmap_args *);
-static int spec_close (struct vop_close_args *);
-static int spec_freeblks (struct vop_freeblks_args *);
-static int spec_fsync (struct vop_fsync_args *);
-static int spec_getpages (struct vop_getpages_args *);
-static int spec_inactive (struct vop_inactive_args *);
-static int spec_ioctl (struct vop_ioctl_args *);
-static int spec_open (struct vop_open_args *);
-static int spec_poll (struct vop_poll_args *);
-static int spec_kqfilter (struct vop_kqfilter_args *);
-static int spec_print (struct vop_print_args *);
-static int spec_read (struct vop_read_args *);
-static int spec_strategy (struct vop_strategy_args *);
-static int spec_write (struct vop_write_args *);
-static void spec_strategy_done(struct bio *nbio);
-static int spec_getattr (struct vop_getattr_args *);
-
-struct vop_ops spec_vnode_vops = {
- .vop_default = vop_defaultop,
- .vop_access = (void *)vop_ebadf,
- .vop_advlock = spec_advlock,
- .vop_bmap = spec_bmap,
- .vop_close = spec_close,
- .vop_old_create = (void *)vop_panic,
- .vop_freeblks = spec_freeblks,
- .vop_fsync = spec_fsync,
- .vop_getpages = spec_getpages,
- .vop_inactive = spec_inactive,
- .vop_ioctl = spec_ioctl,
- .vop_old_link = (void *)vop_panic,
- .vop_old_mkdir = (void *)vop_panic,
- .vop_old_mknod = (void *)vop_panic,
- .vop_open = spec_open,
- .vop_pathconf = vop_stdpathconf,
- .vop_poll = spec_poll,
- .vop_kqfilter = spec_kqfilter,
- .vop_print = spec_print,
- .vop_read = spec_read,
- .vop_readdir = (void *)vop_panic,
- .vop_readlink = (void *)vop_panic,
- .vop_reallocblks = (void *)vop_panic,
- .vop_reclaim = (void *)vop_null,
- .vop_old_remove = (void *)vop_panic,
- .vop_old_rename = (void *)vop_panic,
- .vop_old_rmdir = (void *)vop_panic,
- .vop_setattr = (void *)vop_ebadf,
- .vop_getattr = spec_getattr,
- .vop_strategy = spec_strategy,
- .vop_old_symlink = (void *)vop_panic,
- .vop_write = spec_write
-};
-
-struct vop_ops *spec_vnode_vops_p = &spec_vnode_vops;
-
-VNODEOP_SET(spec_vnode_vops);
-
-extern int dev_ref_debug;
-
-/*
- * spec_vnoperate()
- */
-int
-spec_vnoperate(struct vop_generic_args *ap)
-{
- return (VOCALL(&spec_vnode_vops, ap));
-}
-
-/*
- * Open a special file.
- *
- * spec_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
- * struct file *a_fp)
- */
-/* ARGSUSED */
-static int
-spec_open(struct vop_open_args *ap)
-{
- struct vnode *vp = ap->a_vp;
- cdev_t dev;
- int error;
- const char *cp;
-
- /*
- * Don't allow open if fs is mounted -nodev.
- */
- if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
- return (ENXIO);
- if (vp->v_type == VBLK)
- return (ENXIO);
-
- /*
- * Resolve the device. If the vnode is already open v_rdev may
- * already be resolved. However, if the device changes out from
- * under us we report it (and, for now, we allow it). Since
- * v_release_rdev() zero's v_opencount, we have to save and restore
- * it when replacing the rdev reference.
- */
- if (vp->v_rdev != NULL) {
- dev = get_dev(vp->v_umajor, vp->v_uminor);
- if (dev != vp->v_rdev) {
- int oc = vp->v_opencount;
- kprintf(
- "Warning: spec_open: dev %s was lost",
- vp->v_rdev->si_name);
- v_release_rdev(vp);
- error = v_associate_rdev(vp,
- get_dev(vp->v_umajor, vp->v_uminor));
- if (error) {
- kprintf(", reacquisition failed\n");
- } else {
- vp->v_opencount = oc;
- kprintf(", reacquisition successful\n");
- }
- } else {
- error = 0;
- }
- } else {
- error = v_associate_rdev(vp, get_dev(vp->v_umajor, vp->v_uminor));
- }
- if (error)
- return(error);
-
- /*
- * Prevent degenerate open/close sequences from nulling out rdev.
- */
- dev = vp->v_rdev;
- KKASSERT(dev != NULL);
-
- /*
- * Make this field valid before any I/O in ->d_open. XXX the
- * device itself should probably be required to initialize
- * this field in d_open.
- */
- if (!dev->si_iosize_max)
- dev->si_iosize_max = DFLTPHYS;
-
- /*
- * XXX: Disks get special billing here, but it is mostly wrong.
- * XXX: diskpartitions can overlap and the real checks should
- * XXX: take this into account, and consequently they need to
- * XXX: live in the diskslicing code. Some checks do.
- */
- if (vn_isdisk(vp, NULL) && ap->a_cred != FSCRED &&
- (ap->a_mode & FWRITE)) {
- /*
- * Never allow opens for write if the device is mounted R/W
- */
- if (vp->v_rdev && vp->v_rdev->si_mountpoint &&
- !(vp->v_rdev->si_mountpoint->mnt_flag & MNT_RDONLY)) {
- error = EBUSY;
- goto done;
- }
-
- /*
- * When running in secure mode, do not allow opens
- * for writing if the device is mounted
- */
- if (securelevel >= 1 && vfs_mountedon(vp)) {
- error = EPERM;
- goto done;
- }
-
- /*
- * When running in very secure mode, do not allow
- * opens for writing of any devices.
- */
- if (securelevel >= 2) {
- error = EPERM;
- goto done;
- }
- }
-
- /* XXX: Special casing of ttys for deadfs. Probably redundant */
- if (dev_dflags(dev) & D_TTY)
- vp->v_flag |= VISTTY;
- if ((dev_dflags(dev) & D_SEEKABLE) == 0)
- vp->v_flag |= VNOTSEEKABLE;
-
- /*
- * dev_dopen() is always called for each open. dev_dclose() is
- * only called for the last close unless D_TRACKCLOSE is set.
- */
- vn_unlock(vp);
- error = dev_dopen(dev, ap->a_mode, S_IFCHR, ap->a_cred);
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
-
- if (error)
- goto done;
-
- if (dev_dflags(dev) & D_TTY) {
- if (dev->si_tty) {
- struct tty *tp;
- tp = dev->si_tty;
- if (!tp->t_stop) {
- kprintf("Warning:%s: no t_stop, using nottystop\n", devtoname(dev));
- tp->t_stop = nottystop;
- }
- }
- }
-
- /*
- * If this is 'disk' or disk-like device, associate a VM object
- * with it.
- */
- if (vn_isdisk(vp, NULL)) {
- if (!dev->si_bsize_phys)
- dev->si_bsize_phys = DEV_BSIZE;
- vinitvmio(vp, IDX_TO_OFF(INT_MAX));
- }
- if ((dev_dflags(dev) & D_DISK) == 0) {
- cp = devtoname(dev);
- if (*cp == '#') {
- kprintf("WARNING: driver %s should register devices with make_dev() (cdev_t = \"%s\")\n",
- dev_dname(dev), cp);
- }
- }
-
- /*
- * If we were handed a file pointer we may be able to install a
- * shortcut which issues device read and write operations directly
- * from the fileops rather then having to go through spec_read()
- * and spec_write().
- */
- if (ap->a_fp)
- vn_setspecops(ap->a_fp);
-
- if (dev_ref_debug)
- kprintf("spec_open: %s %d\n", dev->si_name, vp->v_opencount);
-done:
- if (error) {
- if (vp->v_opencount == 0)
- v_release_rdev(vp);
- } else {
- vop_stdopen(ap);
- }
- return (error);
-}
-
-/*
- * Vnode op for read
- *
- * spec_read(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
- * struct ucred *a_cred)
- */
-/* ARGSUSED */
-static int
-spec_read(struct vop_read_args *ap)
-{
- struct vnode *vp;
- struct thread *td;
- struct uio *uio;
- cdev_t dev;
- int error;
-
- vp = ap->a_vp;
- dev = vp->v_rdev;
- uio = ap->a_uio;
- td = uio->uio_td;
-
- if (dev == NULL) /* device was revoked */
- return (EBADF);
- if (uio->uio_resid == 0)
- return (0);
-
- vn_unlock(vp);
- error = dev_dread(dev, uio, ap->a_ioflag);
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
- return (error);
-}
-
-/*
- * Vnode op for write
- *
- * spec_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
- * struct ucred *a_cred)
- */
-/* ARGSUSED */
-static int
-spec_write(struct vop_write_args *ap)
-{
- struct vnode *vp;
- struct thread *td;
- struct uio *uio;
- cdev_t dev;
- int error;
-
- vp = ap->a_vp;
- dev = vp->v_rdev;
- uio = ap->a_uio;
- td = uio->uio_td;
-
- KKASSERT(uio->uio_segflg != UIO_NOCOPY);
-
- if (dev == NULL) /* device was revoked */
- return (EBADF);
-
- vn_unlock(vp);
- error = dev_dwrite(dev, uio, ap->a_ioflag);
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
- return (error);
-}
-
-/*
- * This call modifying an upper layer filesystem's idea of the owner only.
- * It does NOT replace the upper layer filesystem's getattr.
- *
- * XXX spec_getattr() - TEMPORARY - remove when devfs is fully installed.
- * This is a horrible hack. The code will get confused
- * if root chown's a tty device and then fails to chown
- * it back after finishing with it. Non-root chowns are
- * strictly stored in the device and don't have the issue.
- */
-static int
-spec_getattr (struct vop_getattr_args *ap)
-{
- struct vattr *vap = ap->a_vap;
- struct vnode *vp = ap->a_vp;
- cdev_t dev;
-
- if (vp->v_type != VCHR)
- return (0);
- if ((dev = vp->v_rdev) == NULL) {
- if ((dev = vp->v_rdev) == NULL)
- dev = get_dev(vp->v_umajor, vp->v_uminor);
- if (dev == NULL)
- return (0);
- }
- if (vap->va_uid == 0) {
- vap->va_uid = dev->si_uid;
- }
- return (0);
-}
-
-/*
- * Device ioctl operation.
- *
- * spec_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data,
- * int a_fflag, struct ucred *a_cred)
- */
-/* ARGSUSED */
-static int
-spec_ioctl(struct vop_ioctl_args *ap)
-{
- cdev_t dev;
-
- if ((dev = ap->a_vp->v_rdev) == NULL)
- return (EBADF); /* device was revoked */
-
- return (dev_dioctl(dev, ap->a_command, ap->a_data,
- ap->a_fflag, ap->a_cred));
-}
-
-/*
- * spec_poll(struct vnode *a_vp, int a_events, struct ucred *a_cred)
- */
-/* ARGSUSED */
-static int
-spec_poll(struct vop_poll_args *ap)
-{
- cdev_t dev;
-
- if ((dev = ap->a_vp->v_rdev) == NULL)
- return (EBADF); /* device was revoked */
- return (dev_dpoll(dev, ap->a_events));
-}
-
-/*
- * spec_kqfilter(struct vnode *a_vp, struct knote *a_kn)
- */
-/* ARGSUSED */
-static int
-spec_kqfilter(struct vop_kqfilter_args *ap)
-{
- cdev_t dev;
-
- if ((dev = ap->a_vp->v_rdev) == NULL)
- return (EBADF); /* device was revoked */
- return (dev_dkqfilter(dev, ap->a_kn));
-}
-
-/*
- * Synch buffers associated with a block device
- *
- * spec_fsync(struct vnode *a_vp, int a_waitfor)
- */
-/* ARGSUSED */
-static int
-spec_fsync(struct vop_fsync_args *ap)
-{
- struct vnode *vp = ap->a_vp;
- int error;
-
- if (!vn_isdisk(vp, NULL))
- return (0);
-
- /*
- * Flush all dirty buffers associated with a block device.
- */
- error = vfsync(vp, ap->a_waitfor, 10000, NULL, NULL);
- return (error);
-}
-
-/*
- * spec_inactive(struct vnode *a_vp)
- */
-static int
-spec_inactive(struct vop_inactive_args *ap)
-{
- return (0);
-}
-
-/*
- * Convert a vnode strategy call into a device strategy call. Vnode strategy
- * calls are not limited to device DMA limits so we have to deal with the
- * case.
- *
- * spec_strategy(struct vnode *a_vp, struct bio *a_bio)
- */
-static int
-spec_strategy(struct vop_strategy_args *ap)
-{
- struct bio *bio = ap->a_bio;
- struct buf *bp = bio->bio_buf;
- struct buf *nbp;
- struct vnode *vp;
- struct mount *mp;
- int chunksize;
- int maxiosize;
-
- if (bp->b_cmd != BUF_CMD_READ && LIST_FIRST(&bp->b_dep) != NULL)
- buf_start(bp);
-
- /*
- * Collect statistics on synchronous and asynchronous read
- * and write counts for disks that have associated filesystems.
- */
- vp = ap->a_vp;
- KKASSERT(vp->v_rdev != NULL); /* XXX */
- if (vn_isdisk(vp, NULL) && (mp = vp->v_rdev->si_mountpoint) != NULL) {
- if (bp->b_cmd == BUF_CMD_READ) {
- if (bio->bio_flags & BIO_SYNC)
- mp->mnt_stat.f_syncreads++;
- else
- mp->mnt_stat.f_asyncreads++;
- } else {
- if (bio->bio_flags & BIO_SYNC)
- mp->mnt_stat.f_syncwrites++;
- else
- mp->mnt_stat.f_asyncwrites++;
- }
- }
-
- /*
- * Device iosize limitations only apply to read and write. Shortcut
- * the I/O if it fits.
- */
- if ((maxiosize = vp->v_rdev->si_iosize_max) == 0) {
- kprintf("%s: si_iosize_max not set!\n", dev_dname(vp->v_rdev));
- maxiosize = MAXPHYS;
- }
-#if SPEC_CHAIN_DEBUG & 2
- maxiosize = 4096;
-#endif
- if (bp->b_bcount <= maxiosize ||
- (bp->b_cmd != BUF_CMD_READ && bp->b_cmd != BUF_CMD_WRITE)) {
- dev_dstrategy_chain(vp->v_rdev, bio);
- return (0);
- }
-
- /*
- * Clone the buffer and set up an I/O chain to chunk up the I/O.
- */
- nbp = kmalloc(sizeof(*bp), M_DEVBUF, M_INTWAIT|M_ZERO);
- initbufbio(nbp);
- buf_dep_init(nbp);
- BUF_LOCKINIT(nbp);
- BUF_LOCK(nbp, LK_EXCLUSIVE);
- BUF_KERNPROC(nbp);
- nbp->b_vp = vp;
- nbp->b_flags = B_PAGING | (bp->b_flags & B_BNOCLIP);
- nbp->b_data = bp->b_data;
- nbp->b_bio1.bio_done = spec_strategy_done;
- nbp->b_bio1.bio_offset = bio->bio_offset;
- nbp->b_bio1.bio_caller_info1.ptr = bio;
-
- /*
- * Start the first transfer
- */
- if (vn_isdisk(vp, NULL))
- chunksize = vp->v_rdev->si_bsize_phys;
- else
- chunksize = DEV_BSIZE;
- chunksize = maxiosize / chunksize * chunksize;
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy chained I/O chunksize=%d\n", chunksize);
-#endif
- nbp->b_cmd = bp->b_cmd;
- nbp->b_bcount = chunksize;
- nbp->b_bufsize = chunksize; /* used to detect a short I/O */
- nbp->b_bio1.bio_caller_info2.index = chunksize;
-
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p offset %d/%d bcount %d\n",
- bp, 0, bp->b_bcount, nbp->b_bcount);
-#endif
-
- dev_dstrategy(vp->v_rdev, &nbp->b_bio1);
- return (0);
-}
-
-/*
- * Chunked up transfer completion routine - chain transfers until done
- */
-static
-void
-spec_strategy_done(struct bio *nbio)
-{
- struct buf *nbp = nbio->bio_buf;
- struct bio *bio = nbio->bio_caller_info1.ptr; /* original bio */
- struct buf *bp = bio->bio_buf; /* original bp */
- int chunksize = nbio->bio_caller_info2.index; /* chunking */
- int boffset = nbp->b_data - bp->b_data;
-
- if (nbp->b_flags & B_ERROR) {
- /*
- * An error terminates the chain, propogate the error back
- * to the original bp
- */
- bp->b_flags |= B_ERROR;
- bp->b_error = nbp->b_error;
- bp->b_resid = bp->b_bcount - boffset +
- (nbp->b_bcount - nbp->b_resid);
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p error %d bcount %d/%d\n",
- bp, bp->b_error, bp->b_bcount,
- bp->b_bcount - bp->b_resid);
-#endif
- kfree(nbp, M_DEVBUF);
- biodone(bio);
- } else if (nbp->b_resid) {
- /*
- * A short read or write terminates the chain
- */
- bp->b_error = nbp->b_error;
- bp->b_resid = bp->b_bcount - boffset +
- (nbp->b_bcount - nbp->b_resid);
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p short read(1) bcount %d/%d\n",
- bp, bp->b_bcount - bp->b_resid, bp->b_bcount);
-#endif
- kfree(nbp, M_DEVBUF);
- biodone(bio);
- } else if (nbp->b_bcount != nbp->b_bufsize) {
- /*
- * A short read or write can also occur by truncating b_bcount
- */
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p short read(2) bcount %d/%d\n",
- bp, nbp->b_bcount + boffset, bp->b_bcount);
-#endif
- bp->b_error = 0;
- bp->b_bcount = nbp->b_bcount + boffset;
- bp->b_resid = nbp->b_resid;
- kfree(nbp, M_DEVBUF);
- biodone(bio);
- } else if (nbp->b_bcount + boffset == bp->b_bcount) {
- /*
- * No more data terminates the chain
- */
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p finished bcount %d\n",
- bp, bp->b_bcount);
-#endif
- bp->b_error = 0;
- bp->b_resid = 0;
- kfree(nbp, M_DEVBUF);
- biodone(bio);
- } else {
- /*
- * Continue the chain
- */
- boffset += nbp->b_bcount;
- nbp->b_data = bp->b_data + boffset;
- nbp->b_bcount = bp->b_bcount - boffset;
- if (nbp->b_bcount > chunksize)
- nbp->b_bcount = chunksize;
- nbp->b_bio1.bio_done = spec_strategy_done;
- nbp->b_bio1.bio_offset = bio->bio_offset + boffset;
-
-#if SPEC_CHAIN_DEBUG & 1
- kprintf("spec_strategy: chain %p offset %d/%d bcount %d\n",
- bp, boffset, bp->b_bcount, nbp->b_bcount);
-#endif
-
- dev_dstrategy(nbp->b_vp->v_rdev, &nbp->b_bio1);
- }
-}
-
-/*
- * spec_freeblks(struct vnode *a_vp, daddr_t a_addr, daddr_t a_length)
- */
-static int
-spec_freeblks(struct vop_freeblks_args *ap)
-{
- struct buf *bp;
-
- /*
- * XXX: This assumes that strategy does the deed right away.
- * XXX: this may not be TRTTD.
- */
- KKASSERT(ap->a_vp->v_rdev != NULL);
- if ((dev_dflags(ap->a_vp->v_rdev) & D_CANFREE) == 0)
- return (0);
- bp = geteblk(ap->a_length);
- bp->b_cmd = BUF_CMD_FREEBLKS;
- bp->b_bio1.bio_offset = ap->a_offset;
- bp->b_bcount = ap->a_length;
- dev_dstrategy(ap->a_vp->v_rdev, &bp->b_bio1);
- return (0);
-}
-
-/*
- * Implement degenerate case where the block requested is the block
- * returned, and assume that the entire device is contiguous in regards
- * to the contiguous block range (runp and runb).
- *
- * spec_bmap(struct vnode *a_vp, off_t a_loffset,
- * off_t *a_doffsetp, int *a_runp, int *a_runb)
- */
-static int
-spec_bmap(struct vop_bmap_args *ap)
-{
- if (ap->a_doffsetp != NULL)
- *ap->a_doffsetp = ap->a_loffset;
- if (ap->a_runp != NULL)
- *ap->a_runp = MAXBSIZE;
- if (ap->a_runb != NULL) {
- if (ap->a_loffset < MAXBSIZE)
- *ap->a_runb = (int)ap->a_loffset;
- else
- *ap->a_runb = MAXBSIZE;
- }
- return (0);
-}
-
-/*
- * Device close routine
- *
- * spec_close(struct vnode *a_vp, int a_fflag)
- *
- * NOTE: The vnode may or may not be locked on call.
- */
-/* ARGSUSED */
-static int
-spec_close(struct vop_close_args *ap)
-{
- struct proc *p = curproc;
- struct vnode *vp = ap->a_vp;
- cdev_t dev = vp->v_rdev;
- int error;
- int needrelock;
-
- /*
- * A couple of hacks for devices and tty devices. The
- * vnode ref count cannot be used to figure out the
- * last close, but we can use v_opencount now that
- * revoke works properly.
- *
- * Detect the last close on a controlling terminal and clear
- * the session (half-close).
- */
- if (dev)
- reference_dev(dev);
-
- if (p && vp->v_opencount <= 1 && vp == p->p_session->s_ttyvp) {
- p->p_session->s_ttyvp = NULL;
- vrele(vp);
- }
-
- /*
- * Vnodes can be opened and closed multiple times. Do not really
- * close the device unless (1) it is being closed forcibly,
- * (2) the device wants to track closes, or (3) this is the last
- * vnode doing its last close on the device.
- *
- * XXX the VXLOCK (force close) case can leave vnodes referencing
- * a closed device. This might not occur now that our revoke is
- * fixed.
- */
- if (dev && ((vp->v_flag & VRECLAIMED) ||
- (dev_dflags(dev) & D_TRACKCLOSE) ||
- (vp->v_opencount == 1))) {
- needrelock = 0;
- if (vn_islocked(vp)) {
- needrelock = 1;
- vn_unlock(vp);
- }
- error = dev_dclose(dev, ap->a_fflag, S_IFCHR);
- if (needrelock)
- vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
- } else {
- error = 0;
- }
-
- /*
- * Track the actual opens and closes on the vnode. The last close
- * disassociates the rdev. If the rdev is already disassociated or the
- * opencount is already 0, the vnode might have been revoked and no
- * further opencount tracking occurs.
- */
- if (dev) {
- if (dev_ref_debug) {
- kprintf("spec_close: %s %d\n",
- dev->si_name, vp->v_opencount - 1);
- }
- if (vp->v_opencount == 1)
- v_release_rdev(vp);
- release_dev(dev);
- }
- if (vp->v_opencount > 0)
- vop_stdclose(ap);
- return(error);
-}
-
-/*
- * Print out the contents of a special device vnode.
- *
- * spec_print(struct vnode *a_vp)
- */
-static int
-spec_print(struct vop_print_args *ap)
-{
- kprintf("tag VT_NON, dev %s\n", devtoname(ap->a_vp->v_rdev));
- return (0);
-}
-
-/*
- * Special device advisory byte-level locks.
- *
- * spec_advlock(struct vnode *a_vp, caddr_t a_id, int a_op,
- * struct flock *a_fl, int a_flags)
- */
-/* ARGSUSED */
-static int
-spec_advlock(struct vop_advlock_args *ap)
-{
- return ((ap->a_flags & F_POSIX) ? EINVAL : EOPNOTSUPP);
-}
-
-/*
- * spec_getpages() - get pages associated with device vnode.
- *
- * Note that spec_read and spec_write do not use the buffer cache, so we
- * must fully implement getpages here.
- */
-static int
-spec_getpages(struct vop_getpages_args *ap)
-{
- vm_offset_t kva;
- int error;
- int i, pcount, size;
- 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 and do sanity check.
- */
- offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset;
-
- /*
- * Round up physical size for real devices. We cannot round using
- * v_mount's block size data because v_mount has nothing to do with
- * the device. i.e. it's usually '/dev'. We need the physical block
- * size for the device itself.
- *
- * We can't use v_rdev->si_mountpoint because it only exists when the
- * block device is mounted. However, we can use v_rdev.
- */
-
- if (vn_isdisk(vp, NULL))
- blksiz = vp->v_rdev->si_bsize_phys;
- else
- blksiz = DEV_BSIZE;
-
- size = (ap->a_count + blksiz - 1) & ~(blksiz - 1);
-
- bp = getpbuf(NULL);
- 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_cmd = BUF_CMD_READ;
- bp->b_bcount = size;
- bp->b_resid = 0;
- bp->b_runningbufspace = size;
- if (size) {
- runningbufspace += bp->b_runningbufspace;
- ++runningbufcount;
- }
-
- bp->b_bio1.bio_offset = offset;
- bp->b_bio1.bio_done = biodone_sync;
- bp->b_bio1.bio_flags |= BIO_SYNC;
-
- mycpu->gd_cnt.v_vnodein++;
- mycpu->gd_cnt.v_vnodepgsin += pcount;
-
- /* Do the input. */
- vn_strategy(ap->a_vp, &bp->b_bio1);
- biowait(&bp->b_bio1, "spread");
-
- if (bp->b_flags & B_ERROR) {
- if (bp->b_error)
- error = bp->b_error;
- else
- error = EIO;
- }
-
- /*
- * If EOF is encountered we must zero-extend the result in order
- * to ensure that the page does not contain garabge. When no
- * error occurs, an early EOF is indicated if b_bcount got truncated.
- * b_resid is relative to b_bcount and should be 0, but some devices
- * might indicate an EOF with b_resid instead of truncating b_bcount.
- */
- nread = bp->b_bcount - 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;
- vm_page_undirty(m);
- } else if (toff < nread) {
- /*
- * Since this is a VM request, we have to supply the
- * unaligned offset to allow vm_page_set_validclean()
- * to zero sub-DEV_BSIZE'd portions of the page.
- */
- vm_page_set_validclean(m, 0, nread - toff);
- } else {
- m->valid = 0;
- vm_page_undirty(m);
- }
-
- 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;
- /*
- * Since this is a VM request, we need to make the
- * entire page presentable by zeroing invalid sections.
- */
- if (m->valid != VM_PAGE_BITS_ALL)
- vm_page_zero_invalid(m, FALSE);
- }
- }
- if (!gotreqpage) {
- m = ap->a_m[ap->a_reqpage];
- kprintf(
- "spec_getpages:(%s) I/O read failure: (error=%d) bp %p vp %p\n",
- devtoname(vp->v_rdev), error, bp, bp->b_vp);
- kprintf(
- " size: %d, resid: %d, a_count: %d, valid: 0x%x\n",
- size, bp->b_resid, ap->a_count, m->valid);
- kprintf(
- " nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n",
- nread, ap->a_reqpage, (u_long)m->pindex, pcount);
- /*
- * Free the buffer header back to the swap buffer pool.
- */
- relpbuf(bp, NULL);
- return VM_PAGER_ERROR;
- }
- /*
- * Free the buffer header back to the swap buffer pool.
- */
- relpbuf(bp, NULL);
- return VM_PAGER_OK;
-}
polachok's projects / dragonfly.git / commitdiff