d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Put the checks we perform on a bio before calling ::start in their

Browse Source 
own function, handle all validation and truncation at the time we
process the bio instead of when it gets scheduled.
This commit is contained in:
Poul-Henning Kamp 2003-02-06 21:01:36 +00:00
parent 374d145b08
commit e39d70d4fd
1 changed files with 69 additions and 79 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

148
sys/geom/geom_io.c
View File

@ -209,16 +209,63 @@ g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
return (error);
}
static int
g_io_check(struct bio *bp)
{
struct g_consumer *cp;
struct g_provider *pp;
cp = bp->bio_from;
pp = bp->bio_to;
/* Fail if access counters dont allow the operation */
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_GETATTR:
if (cp->acr == 0)
return (EPERM);
break;
case BIO_WRITE:
case BIO_DELETE:
case BIO_SETATTR:
if (cp->acw == 0)
return (EPERM);
break;
default:
return (EPERM);
}
/* if provider is marked for error, don't disturb. */
if (pp->error)
return (pp->error);
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
/* Reject I/O not on sector boundary */
if (bp->bio_offset % pp->sectorsize)
return (EINVAL);
/* Reject I/O not integral sector long */
if (bp->bio_length % pp->sectorsize)
return (EINVAL);
/* Reject requests past the end of media. */
if (bp->bio_offset > pp->mediasize)
return (EIO);
break;
default:
break;
}
return (0);
}
void
g_io_request(struct bio *bp, struct g_consumer *cp)
{
int error;
off_t excess;
KASSERT(cp != NULL, ("NULL cp in g_io_request"));
KASSERT(bp != NULL, ("NULL bp in g_io_request"));
KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request"));
error = 0;
KASSERT(bp->bio_to == NULL, ("consumer not attached in g_io_request"));
bp->bio_from = cp;
bp->bio_to = cp->provider;
bp->bio_error = 0;
@ -227,82 +274,7 @@ g_io_request(struct bio *bp, struct g_consumer *cp)
/* begin_stats(&bp->stats); */
atomic_add_int(&cp->biocount, 1);
/* Fail on unattached consumers */
if (bp->bio_to == NULL) {
g_io_deliver(bp, ENXIO);
return;
}
/* Fail if access doesn't allow operation */
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_GETATTR:
if (cp->acr == 0) {
g_io_deliver(bp, EPERM);
return;
}
break;
case BIO_WRITE:
case BIO_DELETE:
if (cp->acw == 0) {
g_io_deliver(bp, EPERM);
return;
}
break;
case BIO_SETATTR:
/* XXX: Should ideally check for (cp->ace == 0) */
if ((cp->acw == 0)) {
#ifdef DIAGNOSTIC
printf("setattr on %s mode (%d,%d,%d)\n",
cp->provider->name,
cp->acr, cp->acw, cp->ace);
#endif
g_io_deliver(bp, EPERM);
return;
}
break;
default:
g_io_deliver(bp, EPERM);
return;
}
/* if provider is marked for error, don't disturb. */
if (bp->bio_to->error) {
g_io_deliver(bp, bp->bio_to->error);
return;
}
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
/* Reject I/O not on sector boundary */
if (bp->bio_offset % bp->bio_to->sectorsize) {
g_io_deliver(bp, EINVAL);
return;
}
/* Reject I/O not integral sector long */
if (bp->bio_length % bp->bio_to->sectorsize) {
g_io_deliver(bp, EINVAL);
return;
}
/* Reject requests past the end of media. */
if (bp->bio_offset > bp->bio_to->mediasize) {
g_io_deliver(bp, EIO);
return;
}
/* Truncate requests to the end of providers media. */
excess = bp->bio_offset + bp->bio_length;
if (excess > bp->bio_to->mediasize) {
excess -= bp->bio_to->mediasize;
bp->bio_length -= excess;
}
/* Deliver zero length transfers right here. */
if (bp->bio_length == 0) {
g_io_deliver(bp, 0);
return;
}
break;
default:
break;
}
/* Pass it on down. */
g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
bp, bp->bio_from, bp->bio_from->geom->name,
@ -347,11 +319,29 @@ void
g_io_schedule_down(struct thread *tp __unused)
{
struct bio *bp;
off_t excess;
int error;
for(;;) {
bp = g_bioq_first(&g_bio_run_down);
if (bp == NULL)
break;
error = g_io_check(bp);
if (error) {
g_io_deliver(bp, error);
continue;
}
/* Truncate requests to the end of providers media. */
excess = bp->bio_offset + bp->bio_length;
if (excess > bp->bio_to->mediasize) {
excess -= bp->bio_to->mediasize;
bp->bio_length -= excess;
}
/* Deliver zero length transfers right here. */
if (bp->bio_length == 0) {
g_io_deliver(bp, 0);
continue;
}
bp->bio_to->geom->start(bp);
if (pace) {
pace--;