freebsd-dev/sys/kern/subr_disk.c
Poul-Henning Kamp 81661c94b6 Here follows the new kernel dumping infrastructure.
Caveats:

The new savecore program is not complete in the sense that it emulates
enough of the old savecores features to do the job, but implements none
of the options yet.

I would appreciate if a userland hacker could help me out getting savecore
to do what we want it to do from a users point of view, compression,
email-notification, space reservation etc etc.  (send me email if
you are interested).

Currently, savecore will scan all devices marked as "swap" or "dump" in
/etc/fstab _or_ any devices specified on the command-line.

All architectures but i386 lack an implementation of dumpsys(), but
looking at the i386 version it should be trivial for anybody familiar
with the platform(s) to provide this function.

Documentation is quite sparse at this time, more to come.

Details:

ATA and SCSI drivers should work as the dump formatting code has been
removed.  The IDA, TWE and AAC have not yet been converted.

Dumpon now opens the device and uses ioctl(DIOCGKERNELDUMP) to set
the device as dumpdev.  To implement the "off" argument, /dev/null
is used as the device.

Savecore will fail if handed any options since they are not (yet)
implemented.  All devices marked "dump" or "swap" in /etc/fstab
will be scanned and dumps found will be saved to diskfiles
named from the MD5 hash of the header record.  The header record
is dumped in readable format in the .info file.  The kernel
is not saved.  Only complete dumps will be saved.

All maintainer rights for this code are disclaimed: feel free to
improve and extend.

Sponsored by:   DARPA, NAI Labs
2002-03-31 22:37:00 +00:00

431 lines
9.8 KiB
C

/*
* ----------------------------------------------------------------------------
* "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
* ----------------------------------------------------------------------------
*
* $FreeBSD$
*
*/
#include "opt_geom.h"
#ifndef GEOM
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/bio.h>
#include <sys/conf.h>
#include <sys/disk.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <machine/md_var.h>
#include <sys/ctype.h>
static MALLOC_DEFINE(M_DISK, "disk", "disk data");
static d_strategy_t diskstrategy;
static d_open_t diskopen;
static d_close_t diskclose;
static d_ioctl_t diskioctl;
static d_psize_t diskpsize;
static LIST_HEAD(, disk) disklist = LIST_HEAD_INITIALIZER(&disklist);
void disk_dev_synth(dev_t dev);
void
disk_dev_synth(dev_t dev)
{
struct disk *dp;
int u, s, p;
dev_t pdev;
if (dksparebits(dev))
return;
LIST_FOREACH(dp, &disklist, d_list) {
if (major(dev) != dp->d_devsw->d_maj)
continue;
u = dkunit(dev);
p = RAW_PART;
s = WHOLE_DISK_SLICE;
pdev = makedev(dp->d_devsw->d_maj, dkmakeminor(u, s, p));
if (pdev->si_devsw == NULL)
return; /* Probably a unit we don't have */
s = dkslice(dev);
p = dkpart(dev);
if (s == WHOLE_DISK_SLICE && p == RAW_PART) {
/* XXX: actually should not happen */
dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%d",
dp->d_devsw->d_name, u);
dev_depends(pdev, dev);
return;
}
if (s == COMPATIBILITY_SLICE) {
dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%d%c",
dp->d_devsw->d_name, u, 'a' + p);
dev_depends(pdev, dev);
return;
}
if (p != RAW_PART) {
dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%ds%d%c",
dp->d_devsw->d_name, u, s - BASE_SLICE + 1,
'a' + p);
} else {
dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%ds%d",
dp->d_devsw->d_name, u, s - BASE_SLICE + 1);
make_dev_alias(dev, "%s%ds%dc",
dp->d_devsw->d_name, u, s - BASE_SLICE + 1);
}
dev_depends(pdev, dev);
return;
}
}
static void
disk_clone(void *arg, char *name, int namelen, dev_t *dev)
{
struct disk *dp;
char const *d;
char *e;
int j, u, s, p;
dev_t pdev;
if (*dev != NODEV)
return;
LIST_FOREACH(dp, &disklist, d_list) {
d = dp->d_devsw->d_name;
j = dev_stdclone(name, &e, d, &u);
if (j == 0)
continue;
if (u > DKMAXUNIT)
continue;
p = RAW_PART;
s = WHOLE_DISK_SLICE;
pdev = makedev(dp->d_devsw->d_maj, dkmakeminor(u, s, p));
if (pdev->si_disk == NULL)
continue;
if (*e != '\0') {
j = dev_stdclone(e, &e, "s", &s);
if (j == 0)
s = COMPATIBILITY_SLICE;
else if (j == 1 || j == 2)
s += BASE_SLICE - 1;
if (!*e)
; /* ad0s1 case */
else if (e[1] != '\0')
return; /* can never be a disk name */
else if (*e < 'a' || *e > 'h')
return; /* can never be a disk name */
else
p = *e - 'a';
}
if (s == WHOLE_DISK_SLICE && p == RAW_PART) {
return;
} else if (s >= BASE_SLICE && p != RAW_PART) {
*dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%ds%d%c",
pdev->si_devsw->d_name, u, s - BASE_SLICE + 1,
p + 'a');
} else if (s >= BASE_SLICE) {
*dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%ds%d",
pdev->si_devsw->d_name, u, s - BASE_SLICE + 1);
make_dev_alias(*dev, "%s%ds%dc",
pdev->si_devsw->d_name, u, s - BASE_SLICE + 1);
} else {
*dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, "%s%d%c",
pdev->si_devsw->d_name, u, p + 'a');
}
dev_depends(pdev, *dev);
return;
}
}
static void
inherit_raw(dev_t pdev, dev_t dev)
{
dev->si_disk = pdev->si_disk;
dev->si_drv1 = pdev->si_drv1;
dev->si_drv2 = pdev->si_drv2;
dev->si_iosize_max = pdev->si_iosize_max;
dev->si_bsize_phys = pdev->si_bsize_phys;
dev->si_bsize_best = pdev->si_bsize_best;
}
dev_t
disk_create(int unit, struct disk *dp, int flags, struct cdevsw *cdevsw, struct cdevsw *proto)
{
static int once;
dev_t dev;
if (!once) {
EVENTHANDLER_REGISTER(dev_clone, disk_clone, 0, 1000);
once++;
}
bzero(dp, sizeof(*dp));
if (proto->d_open != diskopen) {
*proto = *cdevsw;
proto->d_open = diskopen;
proto->d_close = diskclose;
proto->d_ioctl = diskioctl;
proto->d_strategy = diskstrategy;
proto->d_psize = diskpsize;
}
if (bootverbose)
printf("Creating DISK %s%d\n", cdevsw->d_name, unit);
dev = make_dev(proto, dkmakeminor(unit, WHOLE_DISK_SLICE, RAW_PART),
UID_ROOT, GID_OPERATOR, 0640, "%s%d", cdevsw->d_name, unit);
dev->si_disk = dp;
dp->d_dev = dev;
dp->d_dsflags = flags;
dp->d_devsw = cdevsw;
LIST_INSERT_HEAD(&disklist, dp, d_list);
return (dev);
}
static int
diskdumpconf(u_int onoff, dev_t dev, struct disk *dp)
{
struct dumperinfo di;
struct disklabel *dl;
if (!onoff)
return(set_dumper(NULL));
dl = dsgetlabel(dev, dp->d_slice);
if (!dl)
return (ENXIO);
bzero(&di, sizeof di);
di.dumper = (dumper_t *)dp->d_devsw->d_dump;
di.priv = dp->d_dev;
di.blocksize = dl->d_secsize;
di.mediaoffset = (off_t)(dl->d_partitions[dkpart(dev)].p_offset +
dp->d_slice->dss_slices[dkslice(dev)].ds_offset) * DEV_BSIZE;
di.mediasize =
(off_t)(dl->d_partitions[dkpart(dev)].p_size) * DEV_BSIZE;
return(set_dumper(&di));
}
void
disk_invalidate (struct disk *disk)
{
if (disk->d_slice)
dsgone(&disk->d_slice);
}
void
disk_destroy(dev_t dev)
{
LIST_REMOVE(dev->si_disk, d_list);
bzero(dev->si_disk, sizeof(*dev->si_disk));
dev->si_disk = NULL;
destroy_dev(dev);
return;
}
struct disk *
disk_enumerate(struct disk *disk)
{
if (!disk)
return (LIST_FIRST(&disklist));
else
return (LIST_NEXT(disk, d_list));
}
static int
sysctl_disks(SYSCTL_HANDLER_ARGS)
{
struct disk *disk;
int error, first;
disk = NULL;
first = 1;
while ((disk = disk_enumerate(disk))) {
if (!first) {
error = SYSCTL_OUT(req, " ", 1);
if (error)
return error;
} else {
first = 0;
}
error = SYSCTL_OUT(req, disk->d_dev->si_name, strlen(disk->d_dev->si_name));
if (error)
return error;
}
error = SYSCTL_OUT(req, "", 1);
return error;
}
SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD, 0, NULL,
sysctl_disks, "A", "names of available disks");
/*
* The cdevsw functions
*/
static int
diskopen(dev_t dev, int oflags, int devtype, struct thread *td)
{
dev_t pdev;
struct disk *dp;
int error;
error = 0;
pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
if (!dp)
return (ENXIO);
while (dp->d_flags & DISKFLAG_LOCK) {
dp->d_flags |= DISKFLAG_WANTED;
error = tsleep(dp, PRIBIO | PCATCH, "diskopen", hz);
if (error)
return (error);
}
dp->d_flags |= DISKFLAG_LOCK;
if (!dsisopen(dp->d_slice)) {
if (!pdev->si_iosize_max)
pdev->si_iosize_max = dev->si_iosize_max;
error = dp->d_devsw->d_open(pdev, oflags, devtype, td);
}
/* Inherit properties from the whole/raw dev_t */
inherit_raw(pdev, dev);
if (error)
goto out;
error = dsopen(dev, devtype, dp->d_dsflags, &dp->d_slice, &dp->d_label);
if (!dsisopen(dp->d_slice))
dp->d_devsw->d_close(pdev, oflags, devtype, td);
out:
dp->d_flags &= ~DISKFLAG_LOCK;
if (dp->d_flags & DISKFLAG_WANTED) {
dp->d_flags &= ~DISKFLAG_WANTED;
wakeup(dp);
}
return(error);
}
static int
diskclose(dev_t dev, int fflag, int devtype, struct thread *td)
{
struct disk *dp;
int error;
dev_t pdev;
error = 0;
pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
if (!dp)
return (ENXIO);
dsclose(dev, devtype, dp->d_slice);
if (!dsisopen(dp->d_slice))
error = dp->d_devsw->d_close(dp->d_dev, fflag, devtype, td);
return (error);
}
static void
diskstrategy(struct bio *bp)
{
dev_t pdev;
struct disk *dp;
pdev = dkmodpart(dkmodslice(bp->bio_dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
bp->bio_resid = bp->bio_bcount;
if (dp != bp->bio_dev->si_disk)
inherit_raw(pdev, bp->bio_dev);
if (!dp) {
biofinish(bp, NULL, ENXIO);
return;
}
if (dscheck(bp, dp->d_slice) <= 0) {
biodone(bp);
return;
}
if (bp->bio_bcount == 0) {
biodone(bp);
return;
}
KASSERT(dp->d_devsw != NULL, ("NULL devsw"));
KASSERT(dp->d_devsw->d_strategy != NULL, ("NULL d_strategy"));
dp->d_devsw->d_strategy(bp);
return;
}
static int
diskioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
{
struct disk *dp;
int error;
u_int u;
dev_t pdev;
pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
if (!dp)
return (ENXIO);
if (cmd == DIOCGKERNELDUMP) {
u = *(u_int *)data;
return (diskdumpconf(u, dev, dp));
}
error = dsioctl(dev, cmd, data, fflag, &dp->d_slice);
if (error == ENOIOCTL)
error = dp->d_devsw->d_ioctl(dev, cmd, data, fflag, td);
return (error);
}
static int
diskpsize(dev_t dev)
{
struct disk *dp;
dev_t pdev;
pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
if (!dp)
return (-1);
if (dp != dev->si_disk) {
dev->si_drv1 = pdev->si_drv1;
dev->si_drv2 = pdev->si_drv2;
/* XXX: don't set bp->b_dev->si_disk (?) */
}
return (dssize(dev, &dp->d_slice));
}
SYSCTL_INT(_debug_sizeof, OID_AUTO, disklabel, CTLFLAG_RD,
0, sizeof(struct disklabel), "sizeof(struct disklabel)");
SYSCTL_INT(_debug_sizeof, OID_AUTO, diskslices, CTLFLAG_RD,
0, sizeof(struct diskslices), "sizeof(struct diskslices)");
SYSCTL_INT(_debug_sizeof, OID_AUTO, disk, CTLFLAG_RD,
0, sizeof(struct disk), "sizeof(struct disk)");
#endif