-
-#include "machine/pte.h"
-#ifdef SECSIZE
-#include "file.h"
-#include "ioctl.h"
-#include "disklabel.h"
-#endif SECSIZE
-
-/*
- * Swap IO headers -
- * They contain the necessary information for the swap I/O.
- * At any given time, a swap header can be in three
- * different lists. When free it is in the free list,
- * when allocated and the I/O queued, it is on the swap
- * device list, and finally, if the operation was a dirty
- * page push, when the I/O completes, it is inserted
- * in a list of cleaned pages to be processed by the pageout daemon.
- */
-struct buf *swbuf;
-
-/*
- * swap I/O -
- *
- * If the flag indicates a dirty page push initiated
- * by the pageout daemon, we map the page into the i th
- * virtual page of process 2 (the daemon itself) where i is
- * the index of the swap header that has been allocated.
- * We simply initialize the header and queue the I/O but
- * do not wait for completion. When the I/O completes,
- * biodone() will link the header to a list of cleaned
- * pages to be processed by the pageout daemon.
- */
-swap(p, dblkno, addr, nbytes, rdflg, flag, vp, pfcent)
- struct proc *p;
- swblk_t dblkno;
- caddr_t addr;
- int nbytes, rdflg, flag;
- struct vnode *vp;
- u_int pfcent;
-{
- register struct buf *bp;
- register struct pte *dpte, *vpte;
- register u_int c;
- int p2dp, s, error = 0;
- struct buf *getswbuf();
- int swdone();
-
- bp = getswbuf(PSWP+1);
- bp->b_flags = B_BUSY | B_PHYS | rdflg | flag;
-#ifdef SECSIZE
- bp->b_blksize = DEV_BSIZE;
-#endif SECSIZE
- if ((bp->b_flags & (B_DIRTY|B_PGIN)) == 0)
- if (rdflg == B_READ)
- sum.v_pswpin += btoc(nbytes);
- else
- sum.v_pswpout += btoc(nbytes);
- bp->b_proc = p;
- if (flag & B_DIRTY) {
- p2dp = ((bp - swbuf) * CLSIZE) * KLMAX;
- dpte = dptopte(&proc[2], p2dp);
- vpte = vtopte(p, btop(addr));
- for (c = 0; c < nbytes; c += NBPG) {
- if (vpte->pg_pfnum == 0 || vpte->pg_fod)
- panic("swap bad pte");
- *dpte++ = *vpte++;
- }
- bp->b_un.b_addr = (caddr_t)ctob(dptov(&proc[2], p2dp));
- bp->b_flags |= B_CALL;
- bp->b_iodone = swdone;
- bp->b_pfcent = pfcent;
- } else
- bp->b_un.b_addr = addr;
- while (nbytes > 0) {
- bp->b_blkno = dblkno;
- if (bp->b_vp)
- brelvp(bp);
- VHOLD(vp);
- bp->b_vp = vp;
- bp->b_dev = vp->v_rdev;
- bp->b_bcount = nbytes;
- minphys(bp);
- c = bp->b_bcount;
-#ifdef TRACE
- trace(TR_SWAPIO, vp, bp->b_blkno);
-#endif
- VOP_STRATEGY(bp);
- /* pageout daemon doesn't wait for pushed pages */
- if (flag & B_DIRTY) {
- if (c < nbytes)
- panic("big push");
- return (0);
- }
- bp->b_un.b_addr += c;
- bp->b_flags &= ~B_DONE;
- if (bp->b_flags & B_ERROR) {
- if ((flag & (B_UAREA|B_PAGET)) || rdflg == B_WRITE)
- panic("hard IO err in swap");
- swkill(p, "swap: read error from swap device");
- error = EIO;
- }
- nbytes -= c;
-#ifdef SECSIZE
- if (flag & B_PGIN && nbytes > 0)
- panic("big pgin");
-#endif SECSIZE
- dblkno += btodb(c);
- }
- bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS|B_PAGET|B_UAREA|B_DIRTY);
- freeswbuf(bp);
- return (error);
-}
-
-/*
- * Put a buffer on the clean list after I/O is done.
- * Called from biodone.
- */
-swdone(bp)
- register struct buf *bp;
-{
- register int s;
-
- if (bp->b_flags & B_ERROR)
- panic("IO err in push");
- s = splbio();
- bp->av_forw = bclnlist;
- cnt.v_pgout++;
- cnt.v_pgpgout += bp->b_bcount / NBPG;
- bclnlist = bp;
- if (bswlist.b_flags & B_WANTED)
- wakeup((caddr_t)&proc[2]);
- splx(s);
-}
-
-/*
- * If rout == 0 then killed on swap error, else
- * rout is the name of the routine where we ran out of
- * swap space.
- */
-swkill(p, rout)
- struct proc *p;
- char *rout;
-{
-
- printf("pid %d: %s\n", p->p_pid, rout);
- uprintf("sorry, pid %d was killed in %s\n", p->p_pid, rout);
- /*
- * To be sure no looping (e.g. in vmsched trying to
- * swap out) mark process locked in core (as though
- * done by user) after killing it so noone will try
- * to swap it out.
- */
- psignal(p, SIGKILL);
- p->p_flag |= SULOCK;
-}
projects / unix-history / blobdiff