freebsd-nq/sys/kern/subr_disk.c
Poul-Henning Kamp e0e0b6610e Always initialize bio_resid from bio_bcount in the disk mini-layer so
that the drivers don't have to do it umpteen times.
2001-05-08 08:24:54 +00:00

370 lines
7.8 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 <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);
static void
disk_clone(void *arg, char *name, int namelen, dev_t *dev)
{
struct disk *dp;
char const *d;
int i, u, s, p;
dev_t pdev;
if (*dev != NODEV)
return;
LIST_FOREACH(dp, &disklist, d_list) {
d = dp->d_devsw->d_name;
i = strlen(d);
if (bcmp(d, name, i) != 0)
continue;
u = 0;
if (!isdigit(name[i]))
continue;
while (isdigit(name[i])) {
u *= 10;
u += name[i++] - '0';
}
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 (name[i] != '\0') {
if (name[i] == 's') {
s = 0;
i++;
if (!isdigit(name[i]))
continue;
while (isdigit(name[i])) {
s *= 10;
s += name[i++] - '0';
}
s += BASE_SLICE - 1;
} else {
s = COMPATIBILITY_SLICE;
}
if (name[i] == '\0')
;
else if (name[i] < 'a' || name[i] > 'h')
continue;
else
p = name[i] - 'a';
}
*dev = make_dev(pdev->si_devsw, dkmakeminor(u, s, p),
UID_ROOT, GID_OPERATOR, 0640, name);
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;
bzero(dp, sizeof(*dp));
dev = makedev(cdevsw->d_maj, 0);
if (!devsw(dev)) {
*proto = *cdevsw;
proto->d_open = diskopen;
proto->d_close = diskclose;
proto->d_ioctl = diskioctl;
proto->d_strategy = diskstrategy;
proto->d_psize = diskpsize;
cdevsw_add(proto);
}
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);
if (!once) {
EVENTHANDLER_REGISTER(dev_clone, disk_clone, 0, 1000);
once++;
}
return (dev);
}
int
disk_dumpcheck(dev_t dev, u_int *count, u_int *blkno, u_int *secsize)
{
struct disk *dp;
struct disklabel *dl;
u_int boff;
dp = dev->si_disk;
if (!dp)
return (ENXIO);
if (!dp->d_slice)
return (ENXIO);
dl = dsgetlabel(dev, dp->d_slice);
if (!dl)
return (ENXIO);
*count = (u_long)Maxmem * PAGE_SIZE / dl->d_secsize;
if (dumplo < 0 ||
(dumplo + *count > dl->d_partitions[dkpart(dev)].p_size))
return (EINVAL);
boff = dl->d_partitions[dkpart(dev)].p_offset +
dp->d_slice->dss_slices[dkslice(dev)].ds_offset;
*blkno = boff + dumplo;
*secsize = dl->d_secsize;
return (0);
}
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 proc *p)
{
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, p);
}
/* 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, p);
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 proc *p)
{
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, p);
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 proc *p)
{
struct disk *dp;
int error;
dev_t pdev;
pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
dp = pdev->si_disk;
if (!dp)
return (ENXIO);
error = dsioctl(dev, cmd, data, fflag, &dp->d_slice);
if (error == ENOIOCTL)
error = dp->d_devsw->d_ioctl(dev, cmd, data, fflag, p);
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_DECL(_debug_sizeof);
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)");