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freebsd-skq/sys/dev/md/md.c
Konstantin Belousov 3364c323e6 Implement global and per-uid accounting of the anonymous memory. Add 
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.

The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.

The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.

The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).

Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.

In collaboration with:	pho
Reviewed by:	alc
Approved by:	re (kensmith)
2009-06-23 20:45:22 +00:00

1322 lines
31 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.
* 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/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>
#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, "");
#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 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, 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 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 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 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,
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;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
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));
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;
#if 0
} 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;
}
bzero((void *)(sf_buf_kva(sf) + offs), len);
vm_page_dirty(m);
m->valid = VM_PAGE_BITS_ALL;
#endif
}
sf_buf_free(sf);
sched_unpin();
vm_page_wakeup(m);
vm_page_lock_queues();
vm_page_activate(m);
if (bp->bio_cmd == BIO_WRITE)
vm_page_dirty(m);
vm_page_unlock_queues();
/* 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_set_writeable_dirty(sc->object);
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)))
error = -1;
else
error = EOPNOTSUPP;
} else {
error = sc->start(sc, bp);
}
if (error != -1) {
bp->bio_completed = bp->bio_length;
g_io_deliver(bp, error);
if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
devstat_end_transaction_bio(sc->devstat, bp);
}
}
}
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, *sc2;
int error, max = -1;
*errp = 0;
LIST_FOREACH(sc2, &md_softc_list, list) {
if (unit == sc2->unit) {
*errp = EBUSY;
return (NULL);
}
if (unit == -1 && sc2->unit > max)
max = sc2->unit;
}
if (unit == -1)
unit = max + 1;
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(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);
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, 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;
int error, flags, vfslocked;
error = copyinstr(mdio->md_file, sc->file, sizeof(sc->file), NULL);
if (error != 0)
return (error);
flags = FREAD|FWRITE;
/*
* If the user specified that this is a read only device, unset the
* FWRITE mask before trying to open the backing store.
*/
if ((mdio->md_options & MD_READONLY) != 0)
flags &= ~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(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
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;
caddr_t c;
u_char *ptr, *name, *type;
unsigned len;
mod = NULL;
sx_init(&md_sx, "MD config lock");
g_topology_unlock();
#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;
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);
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);
}
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