X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/5dccc1f9aab79b7cf2bcc09fdf35c1c520e66745..refs/tags/BSD-4_3_Net_2:/usr/src/sys/kern/kern_physio.c diff --git a/usr/src/sys/kern/kern_physio.c b/usr/src/sys/kern/kern_physio.c index 34076d6e27..bf6dc965e6 100644 --- a/usr/src/sys/kern/kern_physio.c +++ b/usr/src/sys/kern/kern_physio.c @@ -1,191 +1,59 @@ /* - * Copyright (c) 1982, 1986 Regents of the University of California. - * All rights reserved. The Berkeley software License Agreement - * specifies the terms and conditions for redistribution. + * Copyright (c) 1982, 1986, 1990 Regents of the University of California. + * All rights reserved. * - * @(#)kern_physio.c 7.11 (Berkeley) %G% + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * from: @(#)kern_physio.c 7.20 (Berkeley) 5/11/91 */ #include "param.h" #include "systm.h" -#include "user.h" #include "buf.h" #include "conf.h" #include "proc.h" #include "seg.h" -#include "vm.h" #include "trace.h" #include "map.h" #include "vnode.h" +#include "specdev.h" -#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); +#ifdef HPUXCOMPAT +#include "user.h" #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; -} /* - * Raw I/O. The arguments are - * The strategy routine for the device - * A buffer, which will either be a special buffer header owned - * exclusively by the device for this purpose, or NULL, - * indicating that we should use a swap buffer - * The device number - * Read/write flag - * Essentially all the work is computing physical addresses and - * validating them. - * If the user has the proper access privilidges, the process is + * This routine does raw device I/O for a user process. + * + * If the user has the proper access privileges, the process is * marked 'delayed unlock' and the pages involved in the I/O are - * faulted and locked. After the completion of the I/O, the above pages + * faulted and locked. After the completion of the I/O, the pages * are unlocked. */ physio(strat, bp, dev, rw, mincnt, uio) @@ -196,137 +64,33 @@ physio(strat, bp, dev, rw, mincnt, uio) u_int (*mincnt)(); struct uio *uio; { - register struct iovec *iov; - register int requested, done; - char *a; - int s, allocbuf = 0, error = 0; - struct buf *getswbuf(); -#ifdef SECSIZE - int bsize; - struct partinfo dpart; -#endif SECSIZE -#ifdef SECSIZE - if ((unsigned)major(dev) < nchrdev && - (*cdevsw[major(dev)].d_ioctl)(dev, DIOCGPART, (caddr_t)&dpart, - FREAD) == 0) - bsize = dpart.disklab->d_secsize; - else - bsize = DEV_BSIZE; -#endif SECSIZE - for (;;) { - if (uio->uio_iovcnt == 0) - return (0); - iov = uio->uio_iov; - if (useracc(iov->iov_base, (u_int)iov->iov_len, - rw==B_READ? B_WRITE : B_READ) == NULL) - return (EFAULT); - s = splbio(); - while (bp->b_flags&B_BUSY) { - bp->b_flags |= B_WANTED; - sleep((caddr_t)bp, PRIBIO+1); - } - if (!allocbuf) { /* only if sharing caller's buffer */ - s = splbio(); - while (bp->b_flags&B_BUSY) { - bp->b_flags |= B_WANTED; - sleep((caddr_t)bp, PRIBIO+1); - } - splx(s); - } - bp->b_error = 0; - bp->b_proc = u.u_procp; -#ifdef SECSIZE - bp->b_blksize = bsize; -#endif SECSIZE - bp->b_un.b_addr = iov->iov_base; - while (iov->iov_len > 0) { - bp->b_flags = B_BUSY | B_PHYS | rw; - bp->b_dev = dev; -#ifdef SECSIZE - bp->b_blkno = uio->uio_offset / bsize; -#else SECSIZE - bp->b_blkno = btodb(uio->uio_offset); -#endif SECSIZE - bp->b_bcount = iov->iov_len; - (*mincnt)(bp); - c = bp->b_bcount; - u.u_procp->p_flag |= SPHYSIO; - vslock(a = bp->b_un.b_addr, c); - physstrat(bp, strat, PRIBIO); - (void) splbio(); - vsunlock(a, c, rw); - u.u_procp->p_flag &= ~SPHYSIO; - if (bp->b_flags&B_WANTED) - wakeup((caddr_t)bp); - splx(s); - c -= bp->b_resid; - bp->b_un.b_addr += c; - iov->iov_len -= c; - uio->uio_resid -= c; - uio->uio_offset += c; - /* temp kludge for tape drives */ - if (bp->b_resid || (bp->b_flags&B_ERROR)) - break; - } - bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS); - error = geterror(bp); - if (bp->b_resid || error) - return (error); - uio->uio_iov++; - uio->uio_iovcnt--; - } - if (allocbuf) - freeswbuf(bp); - return (error); + /* + * Body deleted. + */ + return (EIO); } +/* + * Calculate the maximum size of I/O request that can be requested + * in a single operation. This limit is necessary to prevent a single + * process from being able to lock more than a fixed amount of memory + * in the kernel. + */ u_int minphys(bp) struct buf *bp; { - if (bp->b_bcount > MAXPHYS) - bp->b_bcount = MAXPHYS; -} -static -struct buf * -getswbuf(prio) - int prio; -{ - int s; - struct buf *bp; - - s = splbio(); - while (bswlist.av_forw == NULL) { - bswlist.b_flags |= B_WANTED; - sleep((caddr_t)&bswlist, prio); - } - bp = bswlist.av_forw; - bswlist.av_forw = bp->av_forw; - splx(s); - return (bp); -} - -static -freeswbuf(bp) - struct buf *bp; -{ - int s; - - s = splbio(); - bp->av_forw = bswlist.av_forw; - bswlist.av_forw = bp; - if (bp->b_vp) - brelvp(bp); - if (bswlist.b_flags & B_WANTED) { - bswlist.b_flags &= ~B_WANTED; - wakeup((caddr_t)&bswlist); - wakeup((caddr_t)&proc[2]); - } - splx(s); + /* + * Body deleted. + */ + return; } +/* + * Do a read on a device for a user process. + */ rawread(dev, uio) dev_t dev; struct uio *uio; @@ -335,6 +99,9 @@ rawread(dev, uio) dev, B_READ, minphys, uio)); } +/* + * Do a write on a device for a user process. + */ rawwrite(dev, uio) dev_t dev; struct uio *uio;