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1.1 ! root 1: /* ! 2: * Copyright (c) 1982, 1986 Regents of the University of California. ! 3: * All rights reserved. The Berkeley software License Agreement ! 4: * specifies the terms and conditions for redistribution. ! 5: * ! 6: * @(#)vm_swp.c 7.15 (Berkeley) 6/30/90 ! 7: */ ! 8: ! 9: #include "param.h" ! 10: #include "systm.h" ! 11: #include "user.h" ! 12: #include "buf.h" ! 13: #include "conf.h" ! 14: #include "proc.h" ! 15: #include "seg.h" ! 16: #include "vm.h" ! 17: #include "trace.h" ! 18: #include "map.h" ! 19: #include "vnode.h" ! 20: #include "specdev.h" ! 21: ! 22: #include "machine/pte.h" ! 23: ! 24: /* ! 25: * Swap IO headers - ! 26: * They contain the necessary information for the swap I/O. ! 27: * At any given time, a swap header can be in three ! 28: * different lists. When free it is in the free list, ! 29: * when allocated and the I/O queued, it is on the swap ! 30: * device list, and finally, if the operation was a dirty ! 31: * page push, when the I/O completes, it is inserted ! 32: * in a list of cleaned pages to be processed by the pageout daemon. ! 33: */ ! 34: struct buf *swbuf; ! 35: ! 36: /* ! 37: * swap I/O - ! 38: * ! 39: * If the flag indicates a dirty page push initiated ! 40: * by the pageout daemon, we map the page into the i th ! 41: * virtual page of process 2 (the daemon itself) where i is ! 42: * the index of the swap header that has been allocated. ! 43: * We simply initialize the header and queue the I/O but ! 44: * do not wait for completion. When the I/O completes, ! 45: * biodone() will link the header to a list of cleaned ! 46: * pages to be processed by the pageout daemon. ! 47: */ ! 48: swap(p, dblkno, addr, nbytes, rdflg, flag, vp, pfcent) ! 49: struct proc *p; ! 50: swblk_t dblkno; ! 51: caddr_t addr; ! 52: int nbytes, rdflg, flag; ! 53: struct vnode *vp; ! 54: u_int pfcent; ! 55: { ! 56: register struct buf *bp; ! 57: register struct pte *dpte, *vpte; ! 58: register u_int c; ! 59: int p2dp, s, error = 0; ! 60: struct buf *getswbuf(); ! 61: int swdone(); ! 62: ! 63: bp = getswbuf(PSWP+1); ! 64: bp->b_flags = B_BUSY | B_PHYS | rdflg | flag; ! 65: if ((bp->b_flags & (B_DIRTY|B_PGIN)) == 0) ! 66: if (rdflg == B_READ) ! 67: sum.v_pswpin += btoc(nbytes); ! 68: else ! 69: sum.v_pswpout += btoc(nbytes); ! 70: bp->b_proc = p; ! 71: if (flag & B_DIRTY) { ! 72: p2dp = ((bp - swbuf) * CLSIZE) * KLMAX; ! 73: dpte = dptopte(&proc[2], p2dp); ! 74: vpte = vtopte(p, btop(addr)); ! 75: for (c = 0; c < nbytes; c += NBPG) { ! 76: if (vpte->pg_pfnum == 0 || vpte->pg_fod) ! 77: panic("swap bad pte"); ! 78: *dpte++ = *vpte++; ! 79: } ! 80: bp->b_un.b_addr = (caddr_t)ctob(dptov(&proc[2], p2dp)); ! 81: bp->b_flags |= B_CALL; ! 82: bp->b_iodone = swdone; ! 83: bp->b_pfcent = pfcent; ! 84: } else ! 85: bp->b_un.b_addr = addr; ! 86: while (nbytes > 0) { ! 87: bp->b_blkno = dblkno; ! 88: if (bp->b_vp) ! 89: brelvp(bp); ! 90: VHOLD(vp); ! 91: bp->b_vp = vp; ! 92: bp->b_dev = vp->v_rdev; ! 93: bp->b_bcount = nbytes; ! 94: if ((bp->b_flags & B_READ) == 0) ! 95: vp->v_numoutput++; ! 96: minphys(bp); ! 97: c = bp->b_bcount; ! 98: #ifdef TRACE ! 99: trace(TR_SWAPIO, vp, bp->b_blkno); ! 100: #endif ! 101: #if defined(hp300) || defined(i386) ! 102: vmapbuf(bp); ! 103: #endif ! 104: VOP_STRATEGY(bp); ! 105: /* pageout daemon doesn't wait for pushed pages */ ! 106: if (flag & B_DIRTY) { ! 107: if (c < nbytes) ! 108: panic("big push"); ! 109: return (0); ! 110: } else { ! 111: s = splbio(); ! 112: while ((bp->b_flags & B_DONE) == 0) ! 113: sleep((caddr_t)bp, PSWP); ! 114: splx(s); ! 115: } ! 116: #if defined(hp300) || defined(i386) ! 117: vunmapbuf(bp); ! 118: #endif ! 119: bp->b_un.b_addr += c; ! 120: bp->b_flags &= ~B_DONE; ! 121: if (bp->b_flags & B_ERROR) { ! 122: if ((flag & (B_UAREA|B_PAGET)) || rdflg == B_WRITE) ! 123: panic("hard IO err in swap"); ! 124: swkill(p, "swap: read error from swap device"); ! 125: error = EIO; ! 126: } ! 127: nbytes -= c; ! 128: dblkno += btodb(c); ! 129: } ! 130: bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS|B_PAGET|B_UAREA|B_DIRTY); ! 131: freeswbuf(bp); ! 132: return (error); ! 133: } ! 134: ! 135: /* ! 136: * Put a buffer on the clean list after I/O is done. ! 137: * Called from biodone. ! 138: */ ! 139: swdone(bp) ! 140: register struct buf *bp; ! 141: { ! 142: register int s; ! 143: ! 144: if (bp->b_flags & B_ERROR) ! 145: panic("IO err in push"); ! 146: s = splbio(); ! 147: bp->av_forw = bclnlist; ! 148: cnt.v_pgout++; ! 149: cnt.v_pgpgout += bp->b_bcount / NBPG; ! 150: bclnlist = bp; ! 151: if (bswlist.b_flags & B_WANTED) ! 152: wakeup((caddr_t)&proc[2]); ! 153: #if defined(hp300) || defined(i386) ! 154: vunmapbuf(bp); ! 155: #endif ! 156: splx(s); ! 157: } ! 158: ! 159: /* ! 160: * If rout == 0 then killed on swap error, else ! 161: * rout is the name of the routine where we ran out of ! 162: * swap space. ! 163: */ ! 164: swkill(p, rout) ! 165: struct proc *p; ! 166: char *rout; ! 167: { ! 168: ! 169: printf("pid %d: %s\n", p->p_pid, rout); ! 170: uprintf("sorry, pid %d was killed in %s\n", p->p_pid, rout); ! 171: /* ! 172: * To be sure no looping (e.g. in vmsched trying to ! 173: * swap out) mark process locked in core (as though ! 174: * done by user) after killing it so noone will try ! 175: * to swap it out. ! 176: */ ! 177: psignal(p, SIGKILL); ! 178: p->p_flag |= SULOCK; ! 179: } ! 180: ! 181: /* ! 182: * Raw I/O. The arguments are ! 183: * The strategy routine for the device ! 184: * A buffer, which will either be a special buffer header owned ! 185: * exclusively by the device for this purpose, or NULL, ! 186: * indicating that we should use a swap buffer ! 187: * The device number ! 188: * Read/write flag ! 189: * Essentially all the work is computing physical addresses and ! 190: * validating them. ! 191: * If the user has the proper access privilidges, the process is ! 192: * marked 'delayed unlock' and the pages involved in the I/O are ! 193: * faulted and locked. After the completion of the I/O, the above pages ! 194: * are unlocked. ! 195: */ ! 196: physio(strat, bp, dev, rw, mincnt, uio) ! 197: int (*strat)(); ! 198: register struct buf *bp; ! 199: dev_t dev; ! 200: int rw; ! 201: u_int (*mincnt)(); ! 202: struct uio *uio; ! 203: { ! 204: register struct iovec *iov; ! 205: register int requested, done; ! 206: char *a; ! 207: int s, allocbuf = 0, error = 0; ! 208: struct buf *getswbuf(); ! 209: ! 210: if (bp == NULL) { ! 211: allocbuf = 1; ! 212: bp = getswbuf(PRIBIO+1); ! 213: } ! 214: for (; uio->uio_iovcnt; uio->uio_iov++, uio->uio_iovcnt--) { ! 215: iov = uio->uio_iov; ! 216: if (!useracc(iov->iov_base, (u_int)iov->iov_len, ! 217: rw == B_READ ? B_WRITE : B_READ)) { ! 218: error = EFAULT; ! 219: break; ! 220: } ! 221: if (!allocbuf) { /* only if sharing caller's buffer */ ! 222: s = splbio(); ! 223: while (bp->b_flags&B_BUSY) { ! 224: bp->b_flags |= B_WANTED; ! 225: sleep((caddr_t)bp, PRIBIO+1); ! 226: } ! 227: splx(s); ! 228: } ! 229: bp->b_error = 0; ! 230: bp->b_proc = u.u_procp; ! 231: #ifdef HPUXCOMPAT ! 232: if (ISHPMMADDR(iov->iov_base)) ! 233: bp->b_un.b_addr = (caddr_t)HPMMBASEADDR(iov->iov_base); ! 234: else ! 235: #endif ! 236: bp->b_un.b_addr = iov->iov_base; ! 237: while (iov->iov_len > 0) { ! 238: bp->b_flags = B_BUSY | B_PHYS | B_RAW | rw; ! 239: bp->b_dev = dev; ! 240: bp->b_blkno = btodb(uio->uio_offset); ! 241: bp->b_bcount = iov->iov_len; ! 242: (*mincnt)(bp); ! 243: requested = bp->b_bcount; ! 244: u.u_procp->p_flag |= SPHYSIO; ! 245: vslock(a = bp->b_un.b_addr, requested); ! 246: #if defined(hp300) || defined(i386) ! 247: vmapbuf(bp); ! 248: #endif ! 249: (*strat)(bp); ! 250: s = splbio(); ! 251: while ((bp->b_flags & B_DONE) == 0) ! 252: sleep((caddr_t)bp, PRIBIO); ! 253: #if defined(hp300) || defined(i386) ! 254: vunmapbuf(bp); ! 255: #endif ! 256: vsunlock(a, requested, rw); ! 257: u.u_procp->p_flag &= ~SPHYSIO; ! 258: if (bp->b_flags&B_WANTED) /* rare */ ! 259: wakeup((caddr_t)bp); ! 260: splx(s); ! 261: done = bp->b_bcount - bp->b_resid; ! 262: bp->b_un.b_addr += done; ! 263: iov->iov_len -= done; ! 264: uio->uio_resid -= done; ! 265: uio->uio_offset += done; ! 266: /* temp kludge for disk drives */ ! 267: if (done < requested || bp->b_flags & B_ERROR) ! 268: break; ! 269: } ! 270: bp->b_flags &= ~(B_BUSY | B_WANTED | B_PHYS | B_RAW); ! 271: error = biowait(bp); ! 272: /* temp kludge for disk drives */ ! 273: if (done < requested || bp->b_flags & B_ERROR) ! 274: break; ! 275: } ! 276: #if defined(hp300) ! 277: DCIU(); ! 278: #endif ! 279: if (allocbuf) ! 280: freeswbuf(bp); ! 281: return (error); ! 282: } ! 283: ! 284: u_int ! 285: minphys(bp) ! 286: struct buf *bp; ! 287: { ! 288: if (bp->b_bcount > MAXPHYS) ! 289: bp->b_bcount = MAXPHYS; ! 290: } ! 291: ! 292: static ! 293: struct buf * ! 294: getswbuf(prio) ! 295: int prio; ! 296: { ! 297: int s; ! 298: struct buf *bp; ! 299: ! 300: s = splbio(); ! 301: while (bswlist.av_forw == NULL) { ! 302: bswlist.b_flags |= B_WANTED; ! 303: sleep((caddr_t)&bswlist, prio); ! 304: } ! 305: bp = bswlist.av_forw; ! 306: bswlist.av_forw = bp->av_forw; ! 307: splx(s); ! 308: return (bp); ! 309: } ! 310: ! 311: static ! 312: freeswbuf(bp) ! 313: struct buf *bp; ! 314: { ! 315: int s; ! 316: ! 317: s = splbio(); ! 318: bp->av_forw = bswlist.av_forw; ! 319: bswlist.av_forw = bp; ! 320: if (bp->b_vp) ! 321: brelvp(bp); ! 322: if (bswlist.b_flags & B_WANTED) { ! 323: bswlist.b_flags &= ~B_WANTED; ! 324: wakeup((caddr_t)&bswlist); ! 325: wakeup((caddr_t)&proc[2]); ! 326: } ! 327: splx(s); ! 328: } ! 329: ! 330: rawread(dev, uio) ! 331: dev_t dev; ! 332: struct uio *uio; ! 333: { ! 334: return (physio(cdevsw[major(dev)].d_strategy, (struct buf *)NULL, ! 335: dev, B_READ, minphys, uio)); ! 336: } ! 337: ! 338: rawwrite(dev, uio) ! 339: dev_t dev; ! 340: struct uio *uio; ! 341: { ! 342: return (physio(cdevsw[major(dev)].d_strategy, (struct buf *)NULL, ! 343: dev, B_WRITE, minphys, uio)); ! 344: }
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