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freebsd-dev/sys/dev/md/md.c
Ian Dowse e176446dc8 Move the check for the MD_SHUTDOWN flag to before the tsleep() call 
in the per-device kthread. This ensures that synchronisation with
mddestroy() succeeds even if the kthread was not waiting in tsleep()
at the time of the wakeup(). Among other things, this fixes the
problem of mdconfig getting stuck when an attempt is made to use a
zero-length file as a vnode-type backing store.

Approved by:	re
2002-11-30 22:03:53 +00:00

1154 lines
26 KiB
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/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $FreeBSD$
*
*/
/*
* The following functions are based in the vn(4) driver: mdstart_swap(),
* mdstart_vnode(), mdcreate_swap(), mdcreate_vnode() and mddestroy(),
* and as such under the following copyright:
*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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.
*
* from: Utah Hdr: vn.c 1.13 94/04/02
*
* from: @(#)vn.c 8.6 (Berkeley) 4/1/94
* From: src/sys/dev/vn/vn.c,v 1.122 2000/12/16 16:06:03
*/
#include "opt_md.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/conf.h>
#include <sys/devicestat.h>
#include <sys/disk.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/linker.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mdioctl.h>
#include <sys/mutex.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/stdint.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/swap_pager.h>
#include <vm/uma.h>
#define MD_MODVER 1
#define MD_SHUTDOWN 0x10000 /* Tell worker thread to terminate. */
#ifndef MD_NSECT
#define MD_NSECT (10000 * 2)
#endif
static MALLOC_DEFINE(M_MD, "MD disk", "Memory Disk");
static MALLOC_DEFINE(M_MDSECT, "MD sectors", "Memory Disk Sectors");
static int md_debug;
SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, "");
#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
/* Image gets put here: */
static u_char mfs_root[MD_ROOT_SIZE*1024] = "MFS Filesystem goes here";
static u_char end_mfs_root[] __unused = "MFS Filesystem had better STOP here";
#endif
static int mdrootready;
static int mdunits;
static dev_t status_dev = 0;
#define CDEV_MAJOR 95
static d_strategy_t mdstrategy;
static d_open_t mdopen;
static d_close_t mdclose;
static d_ioctl_t mdioctl, mdctlioctl;
static struct cdevsw md_cdevsw = {
/* open */ mdopen,
/* close */ mdclose,
/* read */ physread,
/* write */ physwrite,
/* ioctl */ mdioctl,
/* poll */ nopoll,
/* mmap */ nommap,
/* strategy */ mdstrategy,
/* name */ MD_NAME,
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ D_DISK | D_CANFREE | D_MEMDISK,
};
static struct cdevsw mdctl_cdevsw = {
/* open */ nullopen,
/* close */ nullclose,
/* read */ noread,
/* write */ nowrite,
/* ioctl */ mdctlioctl,
/* poll */ nopoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ MD_NAME,
/* maj */ CDEV_MAJOR
};
static struct cdevsw mddisk_cdevsw;
static LIST_HEAD(, md_s) md_softc_list = LIST_HEAD_INITIALIZER(&md_softc_list);
#define NINDIR (PAGE_SIZE / sizeof(uintptr_t))
#define NMASK (NINDIR-1)
static int nshift;
struct indir {
uintptr_t *array;
uint total;
uint used;
uint shift;
};
struct md_s {
int unit;
LIST_ENTRY(md_s) list;
struct devstat stats;
struct bio_queue_head bio_queue;
struct disk disk;
dev_t dev;
enum md_types type;
unsigned nsect;
unsigned opencount;
unsigned secsize;
unsigned flags;
char name[20];
struct proc *procp;
/* MD_MALLOC related fields */
struct indir *indir;
uma_zone_t uma;
/* MD_PRELOAD related fields */
u_char *pl_ptr;
unsigned pl_len;
/* MD_VNODE related fields */
struct vnode *vnode;
struct ucred *cred;
/* MD_SWAP related fields */
vm_object_t object;
};
static int mddestroy(struct md_s *sc, struct thread *td);
static struct indir *
new_indir(uint shift)
{
struct indir *ip;
ip = malloc(sizeof *ip, M_MD, M_NOWAIT | M_ZERO);
if (ip == NULL)
return (NULL);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, M_NOWAIT | M_ZERO);
if (ip->array == NULL) {
free(ip, M_MD);
return (NULL);
}
ip->total = NINDIR;
ip->shift = shift;
return (ip);
}
static void
del_indir(struct indir *ip)
{
free(ip->array, M_MDSECT);
free(ip, M_MD);
}
static void
destroy_indir(struct md_s *sc, struct indir *ip)
{
int i;
for (i = 0; i < NINDIR; i++) {
if (!ip->array[i])
continue;
if (ip->shift)
destroy_indir(sc, (struct indir*)(ip->array[i]));
else if (ip->array[i] > 255)
uma_zfree(sc->uma, (void *)(ip->array[i]));
}
del_indir(ip);
}
/*
* This function does the math and alloctes the top level "indir" structure
* for a device of "size" sectors.
*/
static struct indir *
dimension(off_t size)
{
off_t rcnt;
struct indir *ip;
int i, layer;
rcnt = size;
layer = 0;
while (rcnt > NINDIR) {
rcnt /= NINDIR;
layer++;
}
/* figure out log2(NINDIR) */
for (i = NINDIR, nshift = -1; i; nshift++)
i >>= 1;
/*
* XXX: the top layer is probably not fully populated, so we allocate
* too much space for ip->array in new_indir() here.
*/
ip = new_indir(layer * nshift);
return (ip);
}
/*
* Read a given sector
*/
static uintptr_t
s_read(struct indir *ip, off_t offset)
{
struct indir *cip;
int idx;
uintptr_t up;
if (md_debug > 1)
printf("s_read(%jd)\n", (intmax_t)offset);
up = 0;
for (cip = ip; cip != NULL;) {
if (cip->shift) {
idx = (offset >> cip->shift) & NMASK;
up = cip->array[idx];
cip = (struct indir *)up;
continue;
}
idx = offset & NMASK;
return (cip->array[idx]);
}
return (0);
}
/*
* Write a given sector, prune the tree if the value is 0
*/
static int
s_write(struct indir *ip, off_t offset, uintptr_t ptr)
{
struct indir *cip, *lip[10];
int idx, li;
uintptr_t up;
if (md_debug > 1)
printf("s_write(%jd, %p)\n", (intmax_t)offset, (void *)ptr);
up = 0;
li = 0;
cip = ip;
for (;;) {
lip[li++] = cip;
if (cip->shift) {
idx = (offset >> cip->shift) & NMASK;
up = cip->array[idx];
if (up != 0) {
cip = (struct indir *)up;
continue;
}
/* Allocate branch */
cip->array[idx] =
(uintptr_t)new_indir(cip->shift - nshift);
if (cip->array[idx] == 0)
return (ENOSPC);
cip->used++;
up = cip->array[idx];
cip = (struct indir *)up;
continue;
}
/* leafnode */
idx = offset & NMASK;
up = cip->array[idx];
if (up != 0)
cip->used--;
cip->array[idx] = ptr;
if (ptr != 0)
cip->used++;
break;
}
if (cip->used != 0 || li == 1)
return (0);
li--;
while (cip->used == 0 && cip != ip) {
li--;
idx = (offset >> lip[li]->shift) & NMASK;
up = lip[li]->array[idx];
KASSERT(up == (uintptr_t)cip, ("md screwed up"));
del_indir(cip);
lip[li]->array[idx] = 0;
lip[li]->used--;
cip = lip[li];
}
return (0);
}
static int
mdopen(dev_t dev, int flag, int fmt, struct thread *td)
{
struct md_s *sc;
if (md_debug)
printf("mdopen(%s %x %x %p)\n",
devtoname(dev), flag, fmt, td);
sc = dev->si_drv1;
sc->disk.d_sectorsize = sc->secsize;
sc->disk.d_mediasize = (off_t)sc->nsect * sc->secsize;
sc->disk.d_fwsectors = sc->nsect > 63 ? 63 : sc->nsect;
sc->disk.d_fwheads = 1;
sc->opencount++;
return (0);
}
static int
mdclose(dev_t dev, int flags, int fmt, struct thread *td)
{
struct md_s *sc = dev->si_drv1;
sc->opencount--;
return (0);
}
static int
mdioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
if (md_debug)
printf("mdioctl(%s %lx %p %x %p)\n",
devtoname(dev), cmd, addr, flags, td);
return (ENOIOCTL);
}
static int
mdstart_malloc(struct md_s *sc, struct bio *bp)
{
int i, error;
u_char *dst;
unsigned secno, nsec, uc;
uintptr_t sp, osp;
nsec = bp->bio_bcount / sc->secsize;
secno = bp->bio_pblkno;
dst = bp->bio_data;
error = 0;
while (nsec--) {
osp = s_read(sc->indir, secno);
if (bp->bio_cmd == BIO_DELETE) {
if (osp != 0)
error = s_write(sc->indir, secno, 0);
} else if (bp->bio_cmd == BIO_READ) {
if (osp == 0)
bzero(dst, sc->secsize);
else if (osp <= 255)
for (i = 0; i < sc->secsize; i++)
dst[i] = osp;
else
bcopy((void *)osp, dst, sc->secsize);
osp = 0;
} else if (bp->bio_cmd == BIO_WRITE) {
if (sc->flags & MD_COMPRESS) {
uc = dst[0];
for (i = 1; i < sc->secsize; i++)
if (dst[i] != uc)
break;
} else {
i = 0;
uc = 0;
}
if (i == sc->secsize) {
if (osp != uc)
error = s_write(sc->indir, secno, uc);
} else {
if (osp <= 255) {
sp = (uintptr_t) uma_zalloc(
sc->uma, M_NOWAIT);
if (sp == 0) {
error = ENOSPC;
break;
}
bcopy(dst, (void *)sp, sc->secsize);
error = s_write(sc->indir, secno, sp);
} else {
bcopy(dst, (void *)osp, sc->secsize);
osp = 0;
}
}
} else {
error = EOPNOTSUPP;
}
if (osp > 255)
uma_zfree(sc->uma, (void*)osp);
if (error)
break;
secno++;
dst += sc->secsize;
}
bp->bio_resid = 0;
return (error);
}
static int
mdstart_preload(struct md_s *sc, struct bio *bp)
{
if (bp->bio_cmd == BIO_DELETE) {
} else if (bp->bio_cmd == BIO_READ) {
bcopy(sc->pl_ptr + (bp->bio_pblkno << DEV_BSHIFT), bp->bio_data, bp->bio_bcount);
} else {
bcopy(bp->bio_data, sc->pl_ptr + (bp->bio_pblkno << DEV_BSHIFT), bp->bio_bcount);
}
bp->bio_resid = 0;
return (0);
}
static int
mdstart_vnode(struct md_s *sc, struct bio *bp)
{
int error;
struct uio auio;
struct iovec aiov;
struct mount *mp;
/*
* VNODE I/O
*
* If an error occurs, we set BIO_ERROR but we do not set
* B_INVAL because (for a write anyway), the buffer is
* still valid.
*/
bzero(&auio, sizeof(auio));
aiov.iov_base = bp->bio_data;
aiov.iov_len = bp->bio_bcount;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = (vm_ooffset_t)bp->bio_pblkno * sc->secsize;
auio.uio_segflg = UIO_SYSSPACE;
if(bp->bio_cmd == BIO_READ)
auio.uio_rw = UIO_READ;
else
auio.uio_rw = UIO_WRITE;
auio.uio_resid = bp->bio_bcount;
auio.uio_td = curthread;
/*
* When reading set IO_DIRECT to try to avoid double-caching
* the data. When writing IO_DIRECT is not optimal, but we
* must set IO_NOWDRAIN to avoid a wdrain deadlock.
*/
if (bp->bio_cmd == BIO_READ) {
vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY, curthread);
error = VOP_READ(sc->vnode, &auio, IO_DIRECT, sc->cred);
} else {
(void) vn_start_write(sc->vnode, &mp, V_WAIT);
vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY, curthread);
error = VOP_WRITE(sc->vnode, &auio, IO_NOWDRAIN, sc->cred);
vn_finished_write(mp);
}
VOP_UNLOCK(sc->vnode, 0, curthread);
bp->bio_resid = auio.uio_resid;
return (error);
}
static int
mdstart_swap(struct md_s *sc, struct bio *bp)
{
if ((bp->bio_cmd == BIO_DELETE) && (sc->flags & MD_RESERVE))
biodone(bp);
else
vm_pager_strategy(sc->object, bp);
return (-1);
}
static void
mdstrategy(struct bio *bp)
{
struct md_s *sc;
if (md_debug > 1)
printf("mdstrategy(%p) %s %x, %jd, %jd %ld, %p)\n",
(void *)bp, devtoname(bp->bio_dev), bp->bio_flags,
(intmax_t)bp->bio_blkno,
(intmax_t)bp->bio_pblkno,
bp->bio_bcount / DEV_BSIZE,
(void *)bp->bio_data);
sc = bp->bio_dev->si_drv1;
/* XXX: LOCK(sc->lock) */
bioqdisksort(&sc->bio_queue, bp);
/* XXX: UNLOCK(sc->lock) */
wakeup(sc);
}
static void
md_kthread(void *arg)
{
struct md_s *sc;
struct bio *bp;
int error;
sc = arg;
curthread->td_base_pri = PRIBIO;
mtx_lock(&Giant);
for (;;) {
/* XXX: LOCK(unique unit numbers) */
bp = bioq_first(&sc->bio_queue);
if (bp)
bioq_remove(&sc->bio_queue, bp);
/* XXX: UNLOCK(unique unit numbers) */
if (!bp) {
if (sc->flags & MD_SHUTDOWN) {
sc->procp = NULL;
wakeup(&sc->procp);
kthread_exit(0);
}
tsleep(sc, PRIBIO, "mdwait", 0);
continue;
}
switch (sc->type) {
case MD_MALLOC:
devstat_start_transaction(&sc->stats);
error = mdstart_malloc(sc, bp);
break;
case MD_PRELOAD:
devstat_start_transaction(&sc->stats);
error = mdstart_preload(sc, bp);
break;
case MD_VNODE:
devstat_start_transaction(&sc->stats);
error = mdstart_vnode(sc, bp);
break;
case MD_SWAP:
error = mdstart_swap(sc, bp);
break;
default:
panic("Impossible md(type)");
break;
}
if (error != -1)
biofinish(bp, &sc->stats, error);
}
}
static struct md_s *
mdfind(int unit)
{
struct md_s *sc;
/* XXX: LOCK(unique unit numbers) */
LIST_FOREACH(sc, &md_softc_list, list) {
if (sc->unit == unit)
break;
}
/* XXX: UNLOCK(unique unit numbers) */
return (sc);
}
static struct md_s *
mdnew(int unit)
{
struct md_s *sc;
int error, max = -1;
/* XXX: LOCK(unique unit numbers) */
LIST_FOREACH(sc, &md_softc_list, list) {
if (sc->unit == unit) {
/* XXX: UNLOCK(unique unit numbers) */
return (NULL);
}
if (sc->unit > max)
max = sc->unit;
}
if (unit == -1)
unit = max + 1;
if (unit > 255)
return (NULL);
sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
sc->unit = unit;
sprintf(sc->name, "md%d", unit);
error = kthread_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
if (error) {
free(sc, M_MD);
return (NULL);
}
LIST_INSERT_HEAD(&md_softc_list, sc, list);
/* XXX: UNLOCK(unique unit numbers) */
return (sc);
}
static void
mdinit(struct md_s *sc)
{
bioq_init(&sc->bio_queue);
devstat_add_entry(&sc->stats, MD_NAME, sc->unit, sc->secsize,
DEVSTAT_NO_ORDERED_TAGS,
DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER,
DEVSTAT_PRIORITY_OTHER);
sc->dev = disk_create(sc->unit, &sc->disk, 0, &md_cdevsw, &mddisk_cdevsw);
sc->dev->si_drv1 = sc;
}
/*
* XXX: we should check that the range they feed us is mapped.
* XXX: we should implement read-only.
*/
static int
mdcreate_preload(struct md_ioctl *mdio)
{
struct md_s *sc;
if (mdio->md_size == 0)
return (EINVAL);
if (mdio->md_options & ~(MD_AUTOUNIT))
return (EINVAL);
if (mdio->md_options & MD_AUTOUNIT) {
sc = mdnew(-1);
if (sc == NULL)
return (ENOMEM);
mdio->md_unit = sc->unit;
} else {
sc = mdnew(mdio->md_unit);
if (sc == NULL)
return (EBUSY);
}
sc->type = MD_PRELOAD;
sc->secsize = DEV_BSIZE;
sc->nsect = mdio->md_size;
sc->flags = mdio->md_options & MD_FORCE;
/* Cast to pointer size, then to pointer to avoid warning */
sc->pl_ptr = (u_char *)(uintptr_t)mdio->md_base;
sc->pl_len = (mdio->md_size << DEV_BSHIFT);
mdinit(sc);
return (0);
}
static int
mdcreate_malloc(struct md_ioctl *mdio)
{
struct md_s *sc;
off_t u;
uintptr_t sp;
int error;
error = 0;
if (mdio->md_size == 0)
return (EINVAL);
if (mdio->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
return (EINVAL);
/* Compression doesn't make sense if we have reserved space */
if (mdio->md_options & MD_RESERVE)
mdio->md_options &= ~MD_COMPRESS;
if (mdio->md_options & MD_AUTOUNIT) {
sc = mdnew(-1);
if (sc == NULL)
return (ENOMEM);
mdio->md_unit = sc->unit;
} else {
sc = mdnew(mdio->md_unit);
if (sc == NULL)
return (EBUSY);
}
sc->type = MD_MALLOC;
sc->secsize = DEV_BSIZE;
sc->nsect = mdio->md_size;
sc->flags = mdio->md_options & (MD_COMPRESS | MD_FORCE);
sc->indir = dimension(sc->nsect);
sc->uma = uma_zcreate(sc->name, sc->secsize,
NULL, NULL, NULL, NULL, 0x1ff, 0);
if (mdio->md_options & MD_RESERVE) {
for (u = 0; u < sc->nsect; u++) {
sp = (uintptr_t) uma_zalloc(sc->uma, M_NOWAIT | M_ZERO);
if (sp != 0)
error = s_write(sc->indir, u, sp);
else
error = ENOMEM;
if (error)
break;
}
}
if (!error) {
printf("%s%d: Malloc disk\n", MD_NAME, sc->unit);
mdinit(sc);
} else
mddestroy(sc, NULL);
return (error);
}
static int
mdsetcred(struct md_s *sc, struct ucred *cred)
{
char *tmpbuf;
int error = 0;
/*
* Set credits in our softc
*/
if (sc->cred)
crfree(sc->cred);
sc->cred = crhold(cred);
/*
* Horrible kludge to establish credentials for NFS XXX.
*/
if (sc->vnode) {
struct uio auio;
struct iovec aiov;
tmpbuf = malloc(sc->secsize, M_TEMP, M_WAITOK);
bzero(&auio, sizeof(auio));
aiov.iov_base = tmpbuf;
aiov.iov_len = 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(sc->vnode, LK_EXCLUSIVE | LK_RETRY, curthread);
error = VOP_READ(sc->vnode, &auio, 0, sc->cred);
VOP_UNLOCK(sc->vnode, 0, curthread);
free(tmpbuf, M_TEMP);
}
return (error);
}
static int
mdcreate_vnode(struct md_ioctl *mdio, struct thread *td)
{
struct md_s *sc;
struct vattr vattr;
struct nameidata nd;
int error, flags;
flags = FREAD|FWRITE;
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, mdio->md_file, td);
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, mdio->md_file, td);
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, td->td_ucred, td))) {
VOP_UNLOCK(nd.ni_vp, 0, td);
(void) vn_close(nd.ni_vp, flags, td->td_ucred, td);
return (error ? error : EINVAL);
}
VOP_UNLOCK(nd.ni_vp, 0, td);
if (mdio->md_options & MD_AUTOUNIT) {
sc = mdnew(-1);
mdio->md_unit = sc->unit;
} else {
sc = mdnew(mdio->md_unit);
}
if (sc == NULL) {
(void) vn_close(nd.ni_vp, flags, td->td_ucred, td);
return (EBUSY);
}
sc->type = MD_VNODE;
sc->flags = mdio->md_options & MD_FORCE;
if (!(flags & FWRITE))
sc->flags |= MD_READONLY;
sc->secsize = DEV_BSIZE;
sc->vnode = nd.ni_vp;
/*
* If the size is specified, override the file attributes.
*/
if (mdio->md_size)
sc->nsect = mdio->md_size;
else
sc->nsect = vattr.va_size / sc->secsize; /* XXX: round up ? */
if (sc->nsect == 0) {
mddestroy(sc, td);
return (EINVAL);
}
error = mdsetcred(sc, td->td_ucred);
if (error) {
mddestroy(sc, td);
return (error);
}
mdinit(sc);
return (0);
}
static int
mddestroy(struct md_s *sc, struct thread *td)
{
GIANT_REQUIRED;
if (sc->dev != NULL) {
devstat_remove_entry(&sc->stats);
disk_destroy(sc->dev);
}
sc->flags |= MD_SHUTDOWN;
wakeup(sc);
while (sc->procp != NULL)
tsleep(&sc->procp, PRIBIO, "mddestroy", hz / 10);
if (sc->vnode != NULL)
(void)vn_close(sc->vnode, sc->flags & MD_READONLY ?
FREAD : (FREAD|FWRITE), sc->cred, td);
if (sc->cred != NULL)
crfree(sc->cred);
if (sc->object != NULL) {
vm_pager_deallocate(sc->object);
}
if (sc->indir)
destroy_indir(sc, sc->indir);
if (sc->uma)
uma_zdestroy(sc->uma);
/* XXX: LOCK(unique unit numbers) */
LIST_REMOVE(sc, list);
/* XXX: UNLOCK(unique unit numbers) */
free(sc, M_MD);
return (0);
}
static int
mdcreate_swap(struct md_ioctl *mdio, struct thread *td)
{
int error;
struct md_s *sc;
GIANT_REQUIRED;
if (mdio->md_options & MD_AUTOUNIT) {
sc = mdnew(-1);
mdio->md_unit = sc->unit;
} else {
sc = mdnew(mdio->md_unit);
}
if (sc == NULL)
return (EBUSY);
sc->type = MD_SWAP;
/*
* Range check. Disallow negative sizes or any size less then the
* size of a page. Then round to a page.
*/
if (mdio->md_size == 0) {
mddestroy(sc, td);
return (EDOM);
}
/*
* Allocate an OBJT_SWAP object.
*
* sc_secsize is PAGE_SIZE'd
*
* mdio->size is in DEV_BSIZE'd chunks.
* Note the truncation.
*/
sc->secsize = PAGE_SIZE;
sc->nsect = mdio->md_size / (PAGE_SIZE / DEV_BSIZE);
sc->object = vm_pager_allocate(OBJT_SWAP, NULL, sc->secsize * (vm_offset_t)sc->nsect, VM_PROT_DEFAULT, 0);
sc->flags = mdio->md_options & MD_FORCE;
if (mdio->md_options & MD_RESERVE) {
if (swap_pager_reserve(sc->object, 0, sc->nsect) < 0) {
vm_pager_deallocate(sc->object);
sc->object = NULL;
mddestroy(sc, td);
return (EDOM);
}
}
error = mdsetcred(sc, td->td_ucred);
if (error)
mddestroy(sc, td);
else
mdinit(sc);
return (error);
}
static int
mddetach(int unit, struct thread *td)
{
struct md_s *sc;
sc = mdfind(unit);
if (sc == NULL)
return (ENOENT);
if (sc->opencount != 0 && !(sc->flags & MD_FORCE))
return (EBUSY);
switch(sc->type) {
case MD_VNODE:
case MD_SWAP:
case MD_MALLOC:
case MD_PRELOAD:
return (mddestroy(sc, td));
default:
return (EOPNOTSUPP);
}
}
static int
mdctlioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
struct md_ioctl *mdio;
struct md_s *sc;
if (md_debug)
printf("mdctlioctl(%s %lx %p %x %p)\n",
devtoname(dev), cmd, addr, flags, td);
/*
* We assert the version number in the individual ioctl
* handlers instead of out here because (a) it is possible we
* may add another ioctl in the future which doesn't read an
* mdio, and (b) the correct return value for an unknown ioctl
* is ENOIOCTL, not EINVAL.
*/
mdio = (struct md_ioctl *)addr;
switch (cmd) {
case MDIOCATTACH:
if (mdio->md_version != MDIOVERSION)
return (EINVAL);
switch (mdio->md_type) {
case MD_MALLOC:
return (mdcreate_malloc(mdio));
case MD_PRELOAD:
return (mdcreate_preload(mdio));
case MD_VNODE:
return (mdcreate_vnode(mdio, td));
case MD_SWAP:
return (mdcreate_swap(mdio, td));
default:
return (EINVAL);
}
case MDIOCDETACH:
if (mdio->md_version != MDIOVERSION)
return (EINVAL);
if (mdio->md_file != NULL || mdio->md_size != 0 ||
mdio->md_options != 0)
return (EINVAL);
return (mddetach(mdio->md_unit, td));
case MDIOCQUERY:
if (mdio->md_version != MDIOVERSION)
return (EINVAL);
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
mdio->md_type = sc->type;
mdio->md_options = sc->flags;
switch (sc->type) {
case MD_MALLOC:
mdio->md_size = sc->nsect;
break;
case MD_PRELOAD:
mdio->md_size = sc->nsect;
mdio->md_base = (uint64_t)(intptr_t)sc->pl_ptr;
break;
case MD_SWAP:
mdio->md_size = sc->nsect * (PAGE_SIZE / DEV_BSIZE);
break;
case MD_VNODE:
mdio->md_size = sc->nsect;
/* XXX fill this in */
mdio->md_file = NULL;
break;
}
return (0);
default:
return (ENOIOCTL);
};
return (ENOIOCTL);
}
static void
md_preloaded(u_char *image, unsigned length)
{
struct md_s *sc;
sc = mdnew(-1);
if (sc == NULL)
return;
sc->type = MD_PRELOAD;
sc->secsize = DEV_BSIZE;
sc->nsect = length / DEV_BSIZE;
sc->pl_ptr = image;
sc->pl_len = length;
if (sc->unit == 0)
mdrootready = 1;
mdinit(sc);
}
static void
md_drvinit(void *unused)
{
caddr_t mod;
caddr_t c;
u_char *ptr, *name, *type;
unsigned len;
#ifdef MD_ROOT_SIZE
md_preloaded(mfs_root, MD_ROOT_SIZE*1024);
#endif
mod = NULL;
while ((mod = preload_search_next_name(mod)) != NULL) {
name = (char *)preload_search_info(mod, MODINFO_NAME);
type = (char *)preload_search_info(mod, MODINFO_TYPE);
if (name == NULL)
continue;
if (type == NULL)
continue;
if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
continue;
c = preload_search_info(mod, MODINFO_ADDR);
ptr = *(u_char **)c;
c = preload_search_info(mod, MODINFO_SIZE);
len = *(size_t *)c;
printf("%s%d: Preloaded image <%s> %d bytes at %p\n",
MD_NAME, mdunits, name, len, ptr);
md_preloaded(ptr, len);
}
status_dev = make_dev(&mdctl_cdevsw, 0xffff00ff, UID_ROOT, GID_WHEEL,
0600, MDCTL_NAME);
}
static int
md_modevent(module_t mod, int type, void *data)
{
int error;
struct md_s *sc;
switch (type) {
case MOD_LOAD:
md_drvinit(NULL);
break;
case MOD_UNLOAD:
LIST_FOREACH(sc, &md_softc_list, list) {
error = mddetach(sc->unit, curthread);
if (error != 0)
return (error);
}
if (status_dev)
destroy_dev(status_dev);
status_dev = 0;
break;
default:
break;
}
return (0);
}
static moduledata_t md_mod = {
MD_NAME,
md_modevent,
NULL
};
DECLARE_MODULE(md, md_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE+CDEV_MAJOR);
MODULE_VERSION(md, MD_MODVER);
#ifdef MD_ROOT
static void
md_takeroot(void *junk)
{
if (mdrootready)
rootdevnames[0] = "ufs:/dev/md0";
}
SYSINIT(md_root, SI_SUB_MOUNT_ROOT, SI_ORDER_FIRST, md_takeroot, NULL);
#endif
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