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freebsd-skq/sys/dev/md/md.c
Andrey V. Elsukov 657bd8b132 Include sys/sbuf.h directly.
2011-07-11 05:19:28 +00:00

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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.
* 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_geom.h"
#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/fcntl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/limits.h>
#include <sys/linker.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mdioctl.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/sched.h>
#include <sys/sf_buf.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <geom/geom.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>
#include <machine/vmparam.h>
#define MD_MODVER 1
#define MD_SHUTDOWN 0x10000 /* Tell worker thread to terminate. */
#define MD_EXITING 0x20000 /* Worker thread is exiting. */
#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, "");
static int md_malloc_wait;
SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0, "");
#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
/*
* Preloaded image gets put here.
* Applications that patch the object with the image can determine
* the size looking at the start and end markers (strings),
* so we want them contiguous.
*/
static struct {
u_char start[MD_ROOT_SIZE*1024];
u_char end[128];
} mfs_root = {
.start = "MFS Filesystem goes here",
.end = "MFS Filesystem had better STOP here",
};
#endif
static g_init_t g_md_init;
static g_fini_t g_md_fini;
static g_start_t g_md_start;
static g_access_t g_md_access;
static void g_md_dumpconf(struct sbuf *sb, const char *indent,
struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp);
static int mdunits;
static struct cdev *status_dev = 0;
static struct sx md_sx;
static struct unrhdr *md_uh;
static d_ioctl_t mdctlioctl;
static struct cdevsw mdctl_cdevsw = {
.d_version = D_VERSION,
.d_ioctl = mdctlioctl,
.d_name = MD_NAME,
};
struct g_class g_md_class = {
.name = "MD",
.version = G_VERSION,
.init = g_md_init,
.fini = g_md_fini,
.start = g_md_start,
.access = g_md_access,
.dumpconf = g_md_dumpconf,
};
DECLARE_GEOM_CLASS(g_md_class, g_md);
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;
u_int total;
u_int used;
u_int shift;
};
struct md_s {
int unit;
LIST_ENTRY(md_s) list;
struct bio_queue_head bio_queue;
struct mtx queue_mtx;
struct cdev *dev;
enum md_types type;
off_t mediasize;
unsigned sectorsize;
unsigned opencount;
unsigned fwheads;
unsigned fwsectors;
unsigned flags;
char name[20];
struct proc *procp;
struct g_geom *gp;
struct g_provider *pp;
int (*start)(struct md_s *sc, struct bio *bp);
struct devstat *devstat;
/* MD_MALLOC related fields */
struct indir *indir;
uma_zone_t uma;
/* MD_PRELOAD related fields */
u_char *pl_ptr;
size_t pl_len;
/* MD_VNODE related fields */
struct vnode *vnode;
char file[PATH_MAX];
struct ucred *cred;
/* MD_SWAP related fields */
vm_object_t object;
};
static struct indir *
new_indir(u_int shift)
{
struct indir *ip;
ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
| M_ZERO);
if (ip == NULL)
return (NULL);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, (md_malloc_wait ? M_WAITOK : 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 allocates 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 layer;
rcnt = size;
layer = 0;
while (rcnt > NINDIR) {
rcnt /= NINDIR;
layer++;
}
/*
* XXX: the top layer is probably not fully populated, so we allocate
* too much space for ip->array in here.
*/
ip = malloc(sizeof *ip, M_MD, M_WAITOK | M_ZERO);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, M_WAITOK | M_ZERO);
ip->total = NINDIR;
ip->shift = 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
g_md_access(struct g_provider *pp, int r, int w, int e)
{
struct md_s *sc;
sc = pp->geom->softc;
if (sc == NULL) {
if (r <= 0 && w <= 0 && e <= 0)
return (0);
return (ENXIO);
}
r += pp->acr;
w += pp->acw;
e += pp->ace;
if ((sc->flags & MD_READONLY) != 0 && w > 0)
return (EROFS);
if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
sc->opencount = 1;
} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
sc->opencount = 0;
}
return (0);
}
static void
g_md_start(struct bio *bp)
{
struct md_s *sc;
sc = bp->bio_to->geom->softc;
if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
devstat_start_transaction_bio(sc->devstat, bp);
mtx_lock(&sc->queue_mtx);
bioq_disksort(&sc->bio_queue, bp);
mtx_unlock(&sc->queue_mtx);
wakeup(sc);
}
static int
mdstart_malloc(struct md_s *sc, struct bio *bp)
{
int i, error;
u_char *dst;
off_t secno, nsec, uc;
uintptr_t sp, osp;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
break;
default:
return (EOPNOTSUPP);
}
nsec = bp->bio_length / sc->sectorsize;
secno = bp->bio_offset / sc->sectorsize;
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->sectorsize);
else if (osp <= 255)
memset(dst, osp, sc->sectorsize);
else {
bcopy((void *)osp, dst, sc->sectorsize);
cpu_flush_dcache(dst, sc->sectorsize);
}
osp = 0;
} else if (bp->bio_cmd == BIO_WRITE) {
if (sc->flags & MD_COMPRESS) {
uc = dst[0];
for (i = 1; i < sc->sectorsize; i++)
if (dst[i] != uc)
break;
} else {
i = 0;
uc = 0;
}
if (i == sc->sectorsize) {
if (osp != uc)
error = s_write(sc->indir, secno, uc);
} else {
if (osp <= 255) {
sp = (uintptr_t)uma_zalloc(sc->uma,
md_malloc_wait ? M_WAITOK :
M_NOWAIT);
if (sp == 0) {
error = ENOSPC;
break;
}
bcopy(dst, (void *)sp, sc->sectorsize);
error = s_write(sc->indir, secno, sp);
} else {
bcopy(dst, (void *)osp, sc->sectorsize);
osp = 0;
}
}
} else {
error = EOPNOTSUPP;
}
if (osp > 255)
uma_zfree(sc->uma, (void*)osp);
if (error != 0)
break;
secno++;
dst += sc->sectorsize;
}
bp->bio_resid = 0;
return (error);
}
static int
mdstart_preload(struct md_s *sc, struct bio *bp)
{
switch (bp->bio_cmd) {
case BIO_READ:
bcopy(sc->pl_ptr + bp->bio_offset, bp->bio_data,
bp->bio_length);
cpu_flush_dcache(bp->bio_data, bp->bio_length);
break;
case BIO_WRITE:
bcopy(bp->bio_data, sc->pl_ptr + bp->bio_offset,
bp->bio_length);
break;
}
bp->bio_resid = 0;
return (0);
}
static int
mdstart_vnode(struct md_s *sc, struct bio *bp)
{
int error, vfslocked;
struct uio auio;
struct iovec aiov;
struct mount *mp;
struct vnode *vp;
struct thread *td;
off_t end, zerosize;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
case BIO_FLUSH:
break;
default:
return (EOPNOTSUPP);
}
td = curthread;
vp = sc->vnode;
/*
* 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.
*/
if (bp->bio_cmd == BIO_FLUSH) {
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_FSYNC(vp, MNT_WAIT, td);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
bzero(&auio, sizeof(auio));
/*
* Special case for BIO_DELETE. On the surface, this is very
* similar to BIO_WRITE, except that we write from our own
* fixed-length buffer, so we have to loop. The net result is
* that the two cases end up having very little in common.
*/
if (bp->bio_cmd == BIO_DELETE) {
zerosize = ZERO_REGION_SIZE -
(ZERO_REGION_SIZE % sc->sectorsize);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_WRITE;
auio.uio_td = td;
end = bp->bio_offset + bp->bio_length;
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = 0;
while (auio.uio_offset < end) {
aiov.iov_base = __DECONST(void *, zero_region);
aiov.iov_len = end - auio.uio_offset;
if (aiov.iov_len > zerosize)
aiov.iov_len = zerosize;
auio.uio_resid = aiov.iov_len;
error = VOP_WRITE(vp, &auio,
sc->flags & MD_ASYNC ? 0 : IO_SYNC, sc->cred);
if (error != 0)
break;
}
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
bp->bio_resid = end - auio.uio_offset;
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
aiov.iov_base = bp->bio_data;
aiov.iov_len = bp->bio_length;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
auio.uio_segflg = UIO_SYSSPACE;
if (bp->bio_cmd == BIO_READ)
auio.uio_rw = UIO_READ;
else if (bp->bio_cmd == BIO_WRITE)
auio.uio_rw = UIO_WRITE;
else
panic("wrong BIO_OP in mdstart_vnode");
auio.uio_resid = bp->bio_length;
auio.uio_td = td;
/*
* When reading set IO_DIRECT to try to avoid double-caching
* the data. When writing IO_DIRECT is not optimal.
*/
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
if (bp->bio_cmd == BIO_READ) {
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_READ(vp, &auio, IO_DIRECT, sc->cred);
VOP_UNLOCK(vp, 0);
} else {
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_WRITE(vp, &auio, sc->flags & MD_ASYNC ? 0 : IO_SYNC,
sc->cred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
}
VFS_UNLOCK_GIANT(vfslocked);
bp->bio_resid = auio.uio_resid;
return (error);
}
static int
mdstart_swap(struct md_s *sc, struct bio *bp)
{
struct sf_buf *sf;
int rv, offs, len, lastend;
vm_pindex_t i, lastp;
vm_page_t m;
u_char *p;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
break;
default:
return (EOPNOTSUPP);
}
p = bp->bio_data;
/*
* offs is the offset at which to start operating on the
* next (ie, first) page. lastp is the last page on
* which we're going to operate. lastend is the ending
* position within that last page (ie, PAGE_SIZE if
* we're operating on complete aligned pages).
*/
offs = bp->bio_offset % PAGE_SIZE;
lastp = (bp->bio_offset + bp->bio_length - 1) / PAGE_SIZE;
lastend = (bp->bio_offset + bp->bio_length - 1) % PAGE_SIZE + 1;
rv = VM_PAGER_OK;
VM_OBJECT_LOCK(sc->object);
vm_object_pip_add(sc->object, 1);
for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
m = vm_page_grab(sc->object, i,
VM_ALLOC_NORMAL|VM_ALLOC_RETRY);
VM_OBJECT_UNLOCK(sc->object);
sched_pin();
sf = sf_buf_alloc(m, SFB_CPUPRIVATE);
VM_OBJECT_LOCK(sc->object);
if (bp->bio_cmd == BIO_READ) {
if (m->valid != VM_PAGE_BITS_ALL)
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
if (rv == VM_PAGER_ERROR) {
sf_buf_free(sf);
sched_unpin();
vm_page_wakeup(m);
break;
}
bcopy((void *)(sf_buf_kva(sf) + offs), p, len);
cpu_flush_dcache(p, len);
} else if (bp->bio_cmd == BIO_WRITE) {
if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
if (rv == VM_PAGER_ERROR) {
sf_buf_free(sf);
sched_unpin();
vm_page_wakeup(m);
break;
}
bcopy(p, (void *)(sf_buf_kva(sf) + offs), len);
m->valid = VM_PAGE_BITS_ALL;
} else if (bp->bio_cmd == BIO_DELETE) {
if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
if (rv == VM_PAGER_ERROR) {
sf_buf_free(sf);
sched_unpin();
vm_page_wakeup(m);
break;
}
if (len != PAGE_SIZE) {
bzero((void *)(sf_buf_kva(sf) + offs), len);
vm_page_clear_dirty(m, offs, len);
m->valid = VM_PAGE_BITS_ALL;
} else
vm_pager_page_unswapped(m);
}
sf_buf_free(sf);
sched_unpin();
vm_page_wakeup(m);
vm_page_lock(m);
if (bp->bio_cmd == BIO_DELETE && len == PAGE_SIZE)
vm_page_free(m);
else
vm_page_activate(m);
vm_page_unlock(m);
if (bp->bio_cmd == BIO_WRITE)
vm_page_dirty(m);
/* Actions on further pages start at offset 0 */
p += PAGE_SIZE - offs;
offs = 0;
#if 0
if (bootverbose || bp->bio_offset / PAGE_SIZE < 17)
printf("wire_count %d busy %d flags %x hold_count %d act_count %d queue %d valid %d dirty %d @ %d\n",
m->wire_count, m->busy,
m->flags, m->hold_count, m->act_count, m->queue, m->valid, m->dirty, i);
#endif
}
vm_object_pip_subtract(sc->object, 1);
VM_OBJECT_UNLOCK(sc->object);
return (rv != VM_PAGER_ERROR ? 0 : ENOSPC);
}
static void
md_kthread(void *arg)
{
struct md_s *sc;
struct bio *bp;
int error;
sc = arg;
thread_lock(curthread);
sched_prio(curthread, PRIBIO);
thread_unlock(curthread);
if (sc->type == MD_VNODE)
curthread->td_pflags |= TDP_NORUNNINGBUF;
for (;;) {
mtx_lock(&sc->queue_mtx);
if (sc->flags & MD_SHUTDOWN) {
sc->flags |= MD_EXITING;
mtx_unlock(&sc->queue_mtx);
kproc_exit(0);
}
bp = bioq_takefirst(&sc->bio_queue);
if (!bp) {
msleep(sc, &sc->queue_mtx, PRIBIO | PDROP, "mdwait", 0);
continue;
}
mtx_unlock(&sc->queue_mtx);
if (bp->bio_cmd == BIO_GETATTR) {
if ((sc->fwsectors && sc->fwheads &&
(g_handleattr_int(bp, "GEOM::fwsectors",
sc->fwsectors) ||
g_handleattr_int(bp, "GEOM::fwheads",
sc->fwheads))) ||
g_handleattr_int(bp, "GEOM::candelete", 1))
error = -1;
else
error = EOPNOTSUPP;
} else {
error = sc->start(sc, bp);
}
if (error != -1) {
bp->bio_completed = bp->bio_length;
if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
devstat_end_transaction_bio(sc->devstat, bp);
g_io_deliver(bp, error);
}
}
}
static struct md_s *
mdfind(int unit)
{
struct md_s *sc;
LIST_FOREACH(sc, &md_softc_list, list) {
if (sc->unit == unit)
break;
}
return (sc);
}
static struct md_s *
mdnew(int unit, int *errp, enum md_types type)
{
struct md_s *sc;
int error;
*errp = 0;
if (unit == -1)
unit = alloc_unr(md_uh);
else
unit = alloc_unr_specific(md_uh, unit);
if (unit == -1) {
*errp = EBUSY;
return (NULL);
}
sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
sc->type = type;
bioq_init(&sc->bio_queue);
mtx_init(&sc->queue_mtx, "md bio queue", NULL, MTX_DEF);
sc->unit = unit;
sprintf(sc->name, "md%d", unit);
LIST_INSERT_HEAD(&md_softc_list, sc, list);
error = kproc_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
if (error == 0)
return (sc);
LIST_REMOVE(sc, list);
mtx_destroy(&sc->queue_mtx);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
*errp = error;
return (NULL);
}
static void
mdinit(struct md_s *sc)
{
struct g_geom *gp;
struct g_provider *pp;
g_topology_lock();
gp = g_new_geomf(&g_md_class, "md%d", sc->unit);
gp->softc = sc;
pp = g_new_providerf(gp, "md%d", sc->unit);
pp->mediasize = sc->mediasize;
pp->sectorsize = sc->sectorsize;
sc->gp = gp;
sc->pp = pp;
g_error_provider(pp, 0);
g_topology_unlock();
sc->devstat = devstat_new_entry("md", sc->unit, sc->sectorsize,
DEVSTAT_ALL_SUPPORTED, DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
}
/*
* XXX: we should check that the range they feed us is mapped.
* XXX: we should implement read-only.
*/
static int
mdcreate_preload(struct md_s *sc, struct md_ioctl *mdio)
{
if (mdio->md_options & ~(MD_AUTOUNIT | MD_FORCE))
return (EINVAL);
if (mdio->md_base == 0)
return (EINVAL);
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 = (size_t)sc->mediasize;
return (0);
}
static int
mdcreate_malloc(struct md_s *sc, struct md_ioctl *mdio)
{
uintptr_t sp;
int error;
off_t u;
error = 0;
if (mdio->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
return (EINVAL);
if (mdio->md_sectorsize != 0 && !powerof2(mdio->md_sectorsize))
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_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->flags = mdio->md_options & (MD_COMPRESS | MD_FORCE);
sc->indir = dimension(sc->mediasize / sc->sectorsize);
sc->uma = uma_zcreate(sc->name, sc->sectorsize, NULL, NULL, NULL, NULL,
0x1ff, 0);
if (mdio->md_options & MD_RESERVE) {
off_t nsectors;
nsectors = sc->mediasize / sc->sectorsize;
for (u = 0; u < nsectors; u++) {
sp = (uintptr_t)uma_zalloc(sc->uma, (md_malloc_wait ?
M_WAITOK : M_NOWAIT) | M_ZERO);
if (sp != 0)
error = s_write(sc->indir, u, sp);
else
error = ENOMEM;
if (error != 0)
break;
}
}
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->sectorsize, M_TEMP, M_WAITOK);
bzero(&auio, sizeof(auio));
aiov.iov_base = tmpbuf;
aiov.iov_len = sc->sectorsize;
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);
error = VOP_READ(sc->vnode, &auio, 0, sc->cred);
VOP_UNLOCK(sc->vnode, 0);
free(tmpbuf, M_TEMP);
}
return (error);
}
static int
mdcreate_vnode(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
{
struct vattr vattr;
struct nameidata nd;
char *fname;
int error, flags, vfslocked;
/*
* Kernel-originated requests must have the filename appended
* to the mdio structure to protect against malicious software.
*/
fname = mdio->md_file;
if ((void *)fname != (void *)(mdio + 1)) {
error = copyinstr(fname, sc->file, sizeof(sc->file), NULL);
if (error != 0)
return (error);
} else
strlcpy(sc->file, fname, sizeof(sc->file));
/*
* If the user specified that this is a read only device, don't
* set the FWRITE mask before trying to open the backing store.
*/
flags = FREAD | ((mdio->md_options & MD_READONLY) ? 0 : FWRITE);
NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, sc->file, td);
error = vn_open(&nd, &flags, 0, NULL);
if (error != 0)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
if (nd.ni_vp->v_type != VREG) {
error = EINVAL;
goto bad;
}
error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
if (error != 0)
goto bad;
if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
if (nd.ni_vp->v_iflag & VI_DOOMED) {
/* Forced unmount. */
error = EBADF;
goto bad;
}
}
nd.ni_vp->v_vflag |= VV_MD;
VOP_UNLOCK(nd.ni_vp, 0);
if (mdio->md_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->flags = mdio->md_options & (MD_FORCE | MD_ASYNC);
if (!(flags & FWRITE))
sc->flags |= MD_READONLY;
sc->vnode = nd.ni_vp;
error = mdsetcred(sc, td->td_ucred);
if (error != 0) {
sc->vnode = NULL;
vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
nd.ni_vp->v_vflag &= ~VV_MD;
goto bad;
}
VFS_UNLOCK_GIANT(vfslocked);
return (0);
bad:
VOP_UNLOCK(nd.ni_vp, 0);
(void)vn_close(nd.ni_vp, flags, td->td_ucred, td);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
static int
mddestroy(struct md_s *sc, struct thread *td)
{
int vfslocked;
if (sc->gp) {
sc->gp->softc = NULL;
g_topology_lock();
g_wither_geom(sc->gp, ENXIO);
g_topology_unlock();
sc->gp = NULL;
sc->pp = NULL;
}
if (sc->devstat) {
devstat_remove_entry(sc->devstat);
sc->devstat = NULL;
}
mtx_lock(&sc->queue_mtx);
sc->flags |= MD_SHUTDOWN;
wakeup(sc);
while (!(sc->flags & MD_EXITING))
msleep(sc->procp, &sc->queue_mtx, PRIBIO, "mddestroy", hz / 10);
mtx_unlock(&sc->queue_mtx);
mtx_destroy(&sc->queue_mtx);
if (sc->vnode != NULL) {
vfslocked = VFS_LOCK_GIANT(sc->vnode->v_mount);
vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
sc->vnode->v_vflag &= ~VV_MD;
VOP_UNLOCK(sc->vnode, 0);
(void)vn_close(sc->vnode, sc->flags & MD_READONLY ?
FREAD : (FREAD|FWRITE), sc->cred, td);
VFS_UNLOCK_GIANT(vfslocked);
}
if (sc->cred != NULL)
crfree(sc->cred);
if (sc->object != NULL)
vm_object_deallocate(sc->object);
if (sc->indir)
destroy_indir(sc, sc->indir);
if (sc->uma)
uma_zdestroy(sc->uma);
LIST_REMOVE(sc, list);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
return (0);
}
static int
mdcreate_swap(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
{
vm_ooffset_t npage;
int error;
/*
* Range check. Disallow negative sizes or any size less then the
* size of a page. Then round to a page.
*/
if (sc->mediasize == 0 || (sc->mediasize % PAGE_SIZE) != 0)
return (EDOM);
/*
* Allocate an OBJT_SWAP object.
*
* Note the truncation.
*/
npage = mdio->md_mediasize / PAGE_SIZE;
if (mdio->md_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->object = vm_pager_allocate(OBJT_SWAP, NULL, PAGE_SIZE * npage,
VM_PROT_DEFAULT, 0, td->td_ucred);
if (sc->object == NULL)
return (ENOMEM);
sc->flags = mdio->md_options & MD_FORCE;
if (mdio->md_options & MD_RESERVE) {
if (swap_pager_reserve(sc->object, 0, npage) < 0) {
error = EDOM;
goto finish;
}
}
error = mdsetcred(sc, td->td_ucred);
finish:
if (error != 0) {
vm_object_deallocate(sc->object);
sc->object = NULL;
}
return (error);
}
static int
xmdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
struct md_ioctl *mdio;
struct md_s *sc;
int error, i;
if (md_debug)
printf("mdctlioctl(%s %lx %p %x %p)\n",
devtoname(dev), cmd, addr, flags, td);
mdio = (struct md_ioctl *)addr;
if (mdio->md_version != MDIOVERSION)
return (EINVAL);
/*
* 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.
*/
error = 0;
switch (cmd) {
case MDIOCATTACH:
switch (mdio->md_type) {
case MD_MALLOC:
case MD_PRELOAD:
case MD_VNODE:
case MD_SWAP:
break;
default:
return (EINVAL);
}
if (mdio->md_options & MD_AUTOUNIT)
sc = mdnew(-1, &error, mdio->md_type);
else {
if (mdio->md_unit > INT_MAX)
return (EINVAL);
sc = mdnew(mdio->md_unit, &error, mdio->md_type);
}
if (sc == NULL)
return (error);
if (mdio->md_options & MD_AUTOUNIT)
mdio->md_unit = sc->unit;
sc->mediasize = mdio->md_mediasize;
if (mdio->md_sectorsize == 0)
sc->sectorsize = DEV_BSIZE;
else
sc->sectorsize = mdio->md_sectorsize;
error = EDOOFUS;
switch (sc->type) {
case MD_MALLOC:
sc->start = mdstart_malloc;
error = mdcreate_malloc(sc, mdio);
break;
case MD_PRELOAD:
sc->start = mdstart_preload;
error = mdcreate_preload(sc, mdio);
break;
case MD_VNODE:
sc->start = mdstart_vnode;
error = mdcreate_vnode(sc, mdio, td);
break;
case MD_SWAP:
sc->start = mdstart_swap;
error = mdcreate_swap(sc, mdio, td);
break;
}
if (error != 0) {
mddestroy(sc, td);
return (error);
}
/* Prune off any residual fractional sector */
i = sc->mediasize % sc->sectorsize;
sc->mediasize -= i;
mdinit(sc);
return (0);
case MDIOCDETACH:
if (mdio->md_mediasize != 0 ||
(mdio->md_options & ~MD_FORCE) != 0)
return (EINVAL);
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
if (sc->opencount != 0 && !(sc->flags & MD_FORCE) &&
!(mdio->md_options & MD_FORCE))
return (EBUSY);
return (mddestroy(sc, td));
case MDIOCQUERY:
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
mdio->md_type = sc->type;
mdio->md_options = sc->flags;
mdio->md_mediasize = sc->mediasize;
mdio->md_sectorsize = sc->sectorsize;
if (sc->type == MD_VNODE)
error = copyout(sc->file, mdio->md_file,
strlen(sc->file) + 1);
return (error);
case MDIOCLIST:
i = 1;
LIST_FOREACH(sc, &md_softc_list, list) {
if (i == MDNPAD - 1)
mdio->md_pad[i] = -1;
else
mdio->md_pad[i++] = sc->unit;
}
mdio->md_pad[0] = i - 1;
return (0);
default:
return (ENOIOCTL);
};
}
static int
mdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
int error;
sx_xlock(&md_sx);
error = xmdctlioctl(dev, cmd, addr, flags, td);
sx_xunlock(&md_sx);
return (error);
}
static void
md_preloaded(u_char *image, size_t length)
{
struct md_s *sc;
int error;
sc = mdnew(-1, &error, MD_PRELOAD);
if (sc == NULL)
return;
sc->mediasize = length;
sc->sectorsize = DEV_BSIZE;
sc->pl_ptr = image;
sc->pl_len = length;
sc->start = mdstart_preload;
#ifdef MD_ROOT
if (sc->unit == 0)
rootdevnames[0] = "ufs:/dev/md0";
#endif
mdinit(sc);
}
static void
g_md_init(struct g_class *mp __unused)
{
caddr_t mod;
u_char *ptr, *name, *type;
unsigned len;
int i;
/* figure out log2(NINDIR) */
for (i = NINDIR, nshift = -1; i; nshift++)
i >>= 1;
mod = NULL;
sx_init(&md_sx, "MD config lock");
g_topology_unlock();
md_uh = new_unrhdr(0, INT_MAX, NULL);
#ifdef MD_ROOT_SIZE
sx_xlock(&md_sx);
md_preloaded(mfs_root.start, sizeof(mfs_root.start));
sx_xunlock(&md_sx);
#endif
/* XXX: are preload_* static or do they need Giant ? */
while ((mod = preload_search_next_name(mod)) != NULL) {
name = (char *)preload_search_info(mod, MODINFO_NAME);
if (name == NULL)
continue;
type = (char *)preload_search_info(mod, MODINFO_TYPE);
if (type == NULL)
continue;
if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
continue;
ptr = preload_fetch_addr(mod);
len = preload_fetch_size(mod);
if (ptr != NULL && len != 0) {
printf("%s%d: Preloaded image <%s> %d bytes at %p\n",
MD_NAME, mdunits, name, len, ptr);
sx_xlock(&md_sx);
md_preloaded(ptr, len);
sx_xunlock(&md_sx);
}
}
status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL,
0600, MDCTL_NAME);
g_topology_lock();
}
static void
g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
struct g_consumer *cp __unused, struct g_provider *pp)
{
struct md_s *mp;
char *type;
mp = gp->softc;
if (mp == NULL)
return;
switch (mp->type) {
case MD_MALLOC:
type = "malloc";
break;
case MD_PRELOAD:
type = "preload";
break;
case MD_VNODE:
type = "vnode";
break;
case MD_SWAP:
type = "swap";
break;
default:
type = "unknown";
break;
}
if (pp != NULL) {
if (indent == NULL) {
sbuf_printf(sb, " u %d", mp->unit);
sbuf_printf(sb, " s %ju", (uintmax_t) mp->sectorsize);
sbuf_printf(sb, " f %ju", (uintmax_t) mp->fwheads);
sbuf_printf(sb, " fs %ju", (uintmax_t) mp->fwsectors);
sbuf_printf(sb, " l %ju", (uintmax_t) mp->mediasize);
sbuf_printf(sb, " t %s", type);
if (mp->type == MD_VNODE && mp->vnode != NULL)
sbuf_printf(sb, " file %s", mp->file);
} else {
sbuf_printf(sb, "%s<unit>%d</unit>\n", indent,
mp->unit);
sbuf_printf(sb, "%s<sectorsize>%ju</sectorsize>\n",
indent, (uintmax_t) mp->sectorsize);
sbuf_printf(sb, "%s<fwheads>%ju</fwheads>\n",
indent, (uintmax_t) mp->fwheads);
sbuf_printf(sb, "%s<fwsectors>%ju</fwsectors>\n",
indent, (uintmax_t) mp->fwsectors);
sbuf_printf(sb, "%s<length>%ju</length>\n",
indent, (uintmax_t) mp->mediasize);
sbuf_printf(sb, "%s<type>%s</type>\n", indent,
type);
if (mp->type == MD_VNODE && mp->vnode != NULL)
sbuf_printf(sb, "%s<file>%s</file>\n",
indent, mp->file);
}
}
}
static void
g_md_fini(struct g_class *mp __unused)
{
sx_destroy(&md_sx);
if (status_dev != NULL)
destroy_dev(status_dev);
delete_unrhdr(md_uh);
}
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