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Fix an spl window, a page manipulation at interrupt time that was

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incorrect, and correct the support for B_ORDERED.  The spl window
fix was from Peter Wemm, and his questions led me to find the problem with
the interrupt time page manipulation.
This commit is contained in:
John Dyson 1996-09-20 02:26:35 +00:00
parent 82e2dd32b6
commit 08c2c9ddf5
1 changed files with 84 additions and 28 deletions
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112
sys/kern/vfs_bio.c
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@ -18,7 +18,7 @@
* 5. Modifications may be freely made to this file if the above conditions
* are met.
*
* $Id: vfs_bio.c,v 1.100 1996/09/14 04:40:33 dyson Exp $
* $Id: vfs_bio.c,v 1.101 1996/09/18 15:57:41 dyson Exp $
*/
/*
@ -314,11 +314,39 @@ bwrite(struct buf * bp)
VOP_STRATEGY(bp);
/*
* It is possible that the buffer is reused
* before this point if B_ASYNC... What to do?
* Handle ordered writes here.
* If the write was originally flagged as ordered,
* then we check to see if it was converted to async.
* If it was converted to async, and is done now, then
* we release the buffer. Otherwise we clear the
* ordered flag because it is not needed anymore.
*
* Note that biodone has been modified so that it does
* not release ordered buffers. This allows us to have
* a chance to determine whether or not the driver
* has set the async flag in the strategy routine. Otherwise
* if biodone was not modified, then the buffer may have been
* reused before we have had a chance to check the flag.
*/
/* if ((bp->b_flags & B_ASYNC) == 0) { */
if ((oldflags & B_ORDERED) == B_ORDERED) {
int s;
s = splbio();
if (bp->b_flags & B_ASYNC) {
if ((bp->b_flags & B_DONE)) {
if ((bp->b_flags & (B_NOCACHE | B_INVAL | B_ERROR | B_RELBUF)) != 0)
brelse(bp);
else
bqrelse(bp);
}
splx(s);
return (0);
} else {
bp->b_flags &= ~B_ORDERED;
}
splx(s);
}
if ((oldflags & B_ASYNC) == 0) {
int rtval = biowait(bp);
@ -436,7 +464,7 @@ brelse(struct buf * bp)
/* anyone need this block? */
if (bp->b_flags & B_WANTED) {
bp->b_flags &= ~(B_WANTED | B_AGE);
bp->b_flags &= ~B_WANTED;
wakeup(bp);
}
@ -575,7 +603,8 @@ brelse(struct buf * bp)
}
/* unlock */
bp->b_flags &= ~(B_WANTED | B_BUSY | B_ASYNC | B_NOCACHE | B_AGE | B_RELBUF);
bp->b_flags &= ~(B_ORDERED | B_WANTED | B_BUSY |
B_ASYNC | B_NOCACHE | B_AGE | B_RELBUF);
splx(s);
}
@ -614,7 +643,8 @@ bqrelse(struct buf * bp)
}
/* unlock */
bp->b_flags &= ~(B_WANTED | B_BUSY | B_ASYNC | B_NOCACHE | B_AGE | B_RELBUF);
bp->b_flags &= ~(B_ORDERED | B_WANTED | B_BUSY |
B_ASYNC | B_NOCACHE | B_AGE | B_RELBUF);
splx(s);
}
@ -623,29 +653,51 @@ vfs_vmio_release(bp)
struct buf *bp;
{
int i;
vm_page_t m;
for (i = 0; i < bp->b_npages; i++) {
int s;
vm_page_t m;
m = bp->b_pages[i];
bp->b_pages[i] = NULL;
s = splbio();
while ((m->flags & PG_BUSY) || (m->busy != 0)) {
m->flags |= PG_WANTED;
tsleep(m, PVM, "vmiorl", 0);
if ((bp->b_flags & B_ASYNC) == 0) {
while ((m->flags & PG_BUSY) || (m->busy != 0)) {
m->flags |= PG_WANTED;
tsleep(m, PVM, "vmiorl", 0);
}
}
splx(s);
vm_page_unwire(m);
if (m->wire_count == 0) {
if (m->flags & PG_WANTED) {
m->flags &= ~PG_WANTED;
wakeup(m);
}
if (bp->b_flags & B_ASYNC) {
if (m->hold_count == 0) {
if ((m->flags & PG_BUSY) == 0 &&
(m->busy == 0) &&
(m->valid == 0)) {
if(m->dirty == 0)
vm_page_test_dirty(m);
if (m->dirty == 0) {
vm_page_protect(m, VM_PROT_NONE);
vm_page_free(m);
} else {
pagedaemon_wakeup();
}
/*
* This is likely at interrupt time,
* and we cannot block here.
*/
} else if (cnt.v_free_count < cnt.v_free_min) {
pagedaemon_wakeup();
}
}
continue;
}
if (m->valid) {
if(m->dirty == 0)
vm_page_test_dirty(m);
@ -654,7 +706,8 @@ vfs_vmio_release(bp)
*/
if ((vm_swap_size == 0) ||
(cnt.v_free_count < cnt.v_free_min)) {
if ((m->dirty == 0) && (m->hold_count == 0))
if ((m->dirty == 0) &&
(m->hold_count == 0))
vm_page_cache(m);
else
vm_page_deactivate(m);
@ -1250,7 +1303,7 @@ allocbuf(struct buf * bp, int size)
* is the responsibility of vnode_pager_setsize
*/
m = bp->b_pages[i];
s = splhigh();
s = splvm();
while ((m->flags & PG_BUSY) || (m->busy != 0)) {
m->flags |= PG_WANTED;
tsleep(m, PVM, "biodep", 0);
@ -1328,12 +1381,12 @@ allocbuf(struct buf * bp, int size)
vm_page_wire(m);
bp->b_flags &= ~B_CACHE;
} else if (m->flags & PG_BUSY) {
s = splhigh();
m->flags |= PG_WANTED;
tsleep(m, PVM, "pgtblk", 0);
s = splvm();
if (m->flags & PG_BUSY) {
m->flags |= PG_WANTED;
tsleep(m, PVM, "pgtblk", 0);
}
splx(s);
goto doretry;
} else {
if ((curproc != pageproc) &&
@ -1534,11 +1587,14 @@ biodone(register struct buf * bp)
*/
if (bp->b_flags & B_ASYNC) {
if ((bp->b_flags & (B_NOCACHE | B_INVAL | B_ERROR | B_RELBUF)) != 0)
brelse(bp);
else
bqrelse(bp);
if ((bp->b_flags & B_ORDERED) == 0) {
if ((bp->b_flags & (B_NOCACHE | B_INVAL | B_ERROR | B_RELBUF)) != 0)
brelse(bp);
else
bqrelse(bp);
}
} else {
bp->b_flags &= ~B_WANTED;
wakeup(bp);
}
splx(s);