correct no-such-process error

[unix-history] / usr / src / sys / kern / vfs_cluster.c

diff --git a/usr/src/sys/kern/vfs_cluster.c b/usr/src/sys/kern/vfs_cluster.c
index 8b3282d..30c295f 100644 (file)
--- a/usr/src/sys/kern/vfs_cluster.c
+++ b/usr/src/sys/kern/vfs_cluster.c
@@ -1,16 +1,23 @@
-/*     vfs_cluster.c   4.39    82/11/13        */
-
-#include "../h/param.h"
-#include "../h/systm.h"
-#include "../h/dir.h"
-#include "../h/user.h"
-#include "../h/buf.h"
-#include "../h/conf.h"
-#include "../h/proc.h"
-#include "../h/seg.h"
-#include "../h/pte.h"
-#include "../h/vm.h"
-#include "../h/trace.h"
+/*
+ * Copyright (c) 1982 Regents of the University of California.
+ * All rights reserved.  The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ *     @(#)vfs_cluster.c       6.9 (Berkeley) %G%
+ */
+
+#include "../machine/pte.h"
+
+#include "param.h"
+#include "systm.h"
+#include "dir.h"
+#include "user.h"
+#include "buf.h"
+#include "conf.h"
+#include "proc.h"
+#include "seg.h"
+#include "vm.h"
+#include "trace.h"

 
 /*
  * Read in (if necessary) the block and return a buffer pointer.
 
 /*
  * Read in (if necessary) the block and return a buffer pointer.


@@ -27,17 +34,17 @@ bread(dev, blkno, size)
                panic("bread: size 0");
        bp = getblk(dev, blkno, size);
        if (bp->b_flags&B_DONE) {
                panic("bread: size 0");
        bp = getblk(dev, blkno, size);
        if (bp->b_flags&B_DONE) {

-               trace(TR_BREADHIT, dev, blkno);
-               return(bp);
+               trace(TR_BREADHIT, pack(dev, size), blkno);
+               return (bp);

        }
        bp->b_flags |= B_READ;
        if (bp->b_bcount > bp->b_bufsize)
                panic("bread");
        (*bdevsw[major(dev)].d_strategy)(bp);
        }
        bp->b_flags |= B_READ;
        if (bp->b_bcount > bp->b_bufsize)
                panic("bread");
        (*bdevsw[major(dev)].d_strategy)(bp);

-       trace(TR_BREADMISS, dev, blkno);
+       trace(TR_BREADMISS, pack(dev, size), blkno);

        u.u_ru.ru_inblock++;            /* pay for read */
        biowait(bp);
        u.u_ru.ru_inblock++;            /* pay for read */
        biowait(bp);

-       return(bp);
+       return (bp);

 }
 
 /*
 }
 
 /*


@@ -65,10 +72,10 @@ breada(dev, blkno, size, rablkno, rabsize)
                        if (bp->b_bcount > bp->b_bufsize)
                                panic("breada");
                        (*bdevsw[major(dev)].d_strategy)(bp);
                        if (bp->b_bcount > bp->b_bufsize)
                                panic("breada");
                        (*bdevsw[major(dev)].d_strategy)(bp);

-                       trace(TR_BREADMISS, dev, blkno);
+                       trace(TR_BREADMISS, pack(dev, size), blkno);

                        u.u_ru.ru_inblock++;            /* pay for read */
                } else
                        u.u_ru.ru_inblock++;            /* pay for read */
                } else

-                       trace(TR_BREADHIT, dev, blkno);
+                       trace(TR_BREADHIT, pack(dev, size), blkno);

        }
 
        /*
        }
 
        /*


@@ -79,13 +86,13 @@ breada(dev, blkno, size, rablkno, rabsize)
                rabp = getblk(dev, rablkno, rabsize);
                if (rabp->b_flags & B_DONE) {
                        brelse(rabp);
                rabp = getblk(dev, rablkno, rabsize);
                if (rabp->b_flags & B_DONE) {
                        brelse(rabp);

-                       trace(TR_BREADHITRA, dev, blkno);
+                       trace(TR_BREADHITRA, pack(dev, rabsize), blkno);

                } else {
                        rabp->b_flags |= B_READ|B_ASYNC;
                        if (rabp->b_bcount > rabp->b_bufsize)
                                panic("breadrabp");
                        (*bdevsw[major(dev)].d_strategy)(rabp);
                } else {
                        rabp->b_flags |= B_READ|B_ASYNC;
                        if (rabp->b_bcount > rabp->b_bufsize)
                                panic("breadrabp");
                        (*bdevsw[major(dev)].d_strategy)(rabp);

-                       trace(TR_BREADMISSRA, dev, rablock);
+                       trace(TR_BREADMISSRA, pack(dev, rabsize), rablock);

                        u.u_ru.ru_inblock++;            /* pay in advance */
                }
        }
                        u.u_ru.ru_inblock++;            /* pay in advance */
                }
        }


@@ -111,10 +118,10 @@ bwrite(bp)
        register flag;
 
        flag = bp->b_flags;
        register flag;
 
        flag = bp->b_flags;

-       bp->b_flags &= ~(B_READ | B_DONE | B_ERROR | B_DELWRI | B_AGE);
+       bp->b_flags &= ~(B_READ | B_DONE | B_ERROR | B_DELWRI);

        if ((flag&B_DELWRI) == 0)
                u.u_ru.ru_oublock++;            /* noone paid yet */
        if ((flag&B_DELWRI) == 0)
                u.u_ru.ru_oublock++;            /* noone paid yet */

-       trace(TR_BWRITE, bp->b_dev, bp->b_blkno);
+       trace(TR_BWRITE, pack(bp->b_dev, bp->b_bcount), bp->b_blkno);

        if (bp->b_bcount > bp->b_bufsize)
                panic("bwrite");
        (*bdevsw[major(bp->b_dev)].d_strategy)(bp);
        if (bp->b_bcount > bp->b_bufsize)
                panic("bwrite");
        (*bdevsw[major(bp->b_dev)].d_strategy)(bp);


@@ -123,16 +130,12 @@ bwrite(bp)
         * If the write was synchronous, then await i/o completion.
         * If the write was "delayed", then we put the buffer on
         * the q of blocks awaiting i/o completion status.
         * If the write was synchronous, then await i/o completion.
         * If the write was "delayed", then we put the buffer on
         * the q of blocks awaiting i/o completion status.

-        * Otherwise, the i/o must be finished and we check for
-        * an error.

         */
        if ((flag&B_ASYNC) == 0) {
                biowait(bp);
                brelse(bp);
        } else if (flag & B_DELWRI)
                bp->b_flags |= B_AGE;
         */
        if ((flag&B_ASYNC) == 0) {
                biowait(bp);
                brelse(bp);
        } else if (flag & B_DELWRI)
                bp->b_flags |= B_AGE;

-       else
-               u.u_error = geterror(bp);

 }
 
 /*
 }
 
 /*


@@ -179,6 +182,7 @@ brelse(bp)
        register struct buf *flist;
        register s;
 
        register struct buf *flist;
        register s;
 

+       trace(TR_BRELSE, pack(bp->b_dev, bp->b_bufsize), bp->b_blkno);

        /*
         * If someone's waiting for the buffer, or
         * is waiting for a buffer wake 'em up.
        /*
         * If someone's waiting for the buffer, or
         * is waiting for a buffer wake 'em up.


@@ -198,7 +202,7 @@ brelse(bp)
        /*
         * Stick the buffer back on a free list.
         */
        /*
         * Stick the buffer back on a free list.
         */

-       s = spl6();
+       s = splbio();

        if (bp->b_bufsize <= 0) {
                /* block has no buffer ... put at front of unused buffer list */
                flist = &bfreelist[BQ_EMPTY];
        if (bp->b_bufsize <= 0) {
                /* block has no buffer ... put at front of unused buffer list */
                flist = &bfreelist[BQ_EMPTY];


@@ -269,8 +273,18 @@ getblk(dev, blkno, size)
        register struct buf *bp, *dp;
        int s;
 
        register struct buf *bp, *dp;
        int s;
 

-       if ((unsigned)blkno >= 1 << (sizeof(int)*NBBY-PGSHIFT))
-               blkno = 1 << ((sizeof(int)*NBBY-PGSHIFT) + 1);
+       if (size > MAXBSIZE)
+               panic("getblk: size too big");
+       /*
+        * To prevent overflow of 32-bit ints when converting block
+        * numbers to byte offsets, blknos > 2^32 / DEV_BSIZE are set
+        * to the maximum number that can be converted to a byte offset
+        * without overflow. This is historic code; what bug it fixed,
+        * or whether it is still a reasonable thing to do is open to
+        * dispute. mkm 9/85
+        */
+       if ((unsigned)blkno >= 1 << (sizeof(int)*NBBY-DEV_BSHIFT))
+               blkno = 1 << ((sizeof(int)*NBBY-DEV_BSHIFT) + 1);

        /*
         * Search the cache for the block.  If we hit, but
         * the buffer is in use for i/o, then we wait until
        /*
         * Search the cache for the block.  If we hit, but
         * the buffer is in use for i/o, then we wait until


@@ -282,7 +296,7 @@ loop:
                if (bp->b_blkno != blkno || bp->b_dev != dev ||
                    bp->b_flags&B_INVAL)
                        continue;
                if (bp->b_blkno != blkno || bp->b_dev != dev ||
                    bp->b_flags&B_INVAL)
                        continue;

-               s = spl6();
+               s = splbio();

                if (bp->b_flags&B_BUSY) {
                        bp->b_flags |= B_WANTED;
                        sleep((caddr_t)bp, PRIBIO+1);
                if (bp->b_flags&B_BUSY) {
                        bp->b_flags |= B_WANTED;
                        sleep((caddr_t)bp, PRIBIO+1);


@@ -291,10 +305,10 @@ loop:
                }
                splx(s);
                notavail(bp);
                }
                splx(s);
                notavail(bp);

-               if (brealloc(bp, size) == 0)
+               if (bp->b_bcount != size && brealloc(bp, size) == 0)

                        goto loop;
                bp->b_flags |= B_CACHE;
                        goto loop;
                bp->b_flags |= B_CACHE;

-               return(bp);
+               return (bp);

        }
        if (major(dev) >= nblkdev)
                panic("blkdev");
        }
        if (major(dev) >= nblkdev)
                panic("blkdev");


@@ -307,7 +321,7 @@ loop:
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;

-       return(bp);
+       return (bp);

 }
 
 /*
 }
 
 /*


@@ -320,6 +334,8 @@ geteblk(size)
 {
        register struct buf *bp, *flist;
 
 {
        register struct buf *bp, *flist;
 

+       if (size > MAXBSIZE)
+               panic("geteblk: size too big");

 loop:
        bp = getnewbuf();
        bp->b_flags |= B_INVAL;
 loop:
        bp = getnewbuf();
        bp->b_flags |= B_INVAL;


@@ -331,11 +347,12 @@ loop:
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;

-       return(bp);
+       return (bp);

 }
 
 /*
  * Allocate space associated with a buffer.
 }
 
 /*
  * Allocate space associated with a buffer.

+ * If can't get space, buffer is released

  */
 brealloc(bp, size)
        register struct buf *bp;
  */
 brealloc(bp, size)
        register struct buf *bp;


@@ -359,15 +376,13 @@ brealloc(bp, size)
                }
                if (bp->b_flags & B_LOCKED)
                        panic("brealloc");
                }
                if (bp->b_flags & B_LOCKED)
                        panic("brealloc");

-               allocbuf(bp, size);
-               return (1);
+               return (allocbuf(bp, size));

        }
        bp->b_flags &= ~B_DONE;
        }
        bp->b_flags &= ~B_DONE;

-       if (bp->b_dev == NODEV) {
-               allocbuf(bp, size);
-               return (1);
-       }
+       if (bp->b_dev == NODEV)
+               return (allocbuf(bp, size));

 
 

+       trace(TR_BREALLOC, pack(bp->b_dev, size), bp->b_blkno);

        /*
         * Search cache for any buffers that overlap the one that we
         * are trying to allocate. Overlapping buffers must be marked
        /*
         * Search cache for any buffers that overlap the one that we
         * are trying to allocate. Overlapping buffers must be marked


@@ -377,7 +392,7 @@ brealloc(bp, size)
         * when two buffer are trying to get the same set of disk blocks.
         */
        start = bp->b_blkno;
         * when two buffer are trying to get the same set of disk blocks.
         */
        start = bp->b_blkno;

-       last = start + (size / DEV_BSIZE) - 1;
+       last = start + btodb(size) - 1;

        dp = BUFHASH(bp->b_dev, bp->b_blkno);
 loop:
        for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) {
        dp = BUFHASH(bp->b_dev, bp->b_blkno);
 loop:
        for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) {


@@ -385,9 +400,9 @@ loop:
                        continue;
                /* look for overlap */
                if (ep->b_bcount == 0 || ep->b_blkno > last ||
                        continue;
                /* look for overlap */
                if (ep->b_bcount == 0 || ep->b_blkno > last ||

-                   ep->b_blkno + (ep->b_bcount / DEV_BSIZE) <= start)
+                   ep->b_blkno + btodb(ep->b_bcount) <= start)

                        continue;
                        continue;

-               s = spl6();
+               s = splbio();

                if (ep->b_flags&B_BUSY) {
                        ep->b_flags |= B_WANTED;
                        sleep((caddr_t)ep, PRIBIO+1);
                if (ep->b_flags&B_BUSY) {
                        ep->b_flags |= B_WANTED;
                        sleep((caddr_t)ep, PRIBIO+1);


@@ -403,89 +418,7 @@ loop:
                ep->b_flags |= B_INVAL;
                brelse(ep);
        }
                ep->b_flags |= B_INVAL;
                brelse(ep);
        }

-       allocbuf(bp, size);
-       return (1);
-}
-
-/*
- * Expand or contract the actual memory allocated to a buffer.
- */
-allocbuf(tp, size)
-       register struct buf *tp;
-       int size;
-{
-       register struct buf *bp, *ep;
-       int sizealloc, take;
-
-       sizealloc = roundup(size, CLBYTES);
-       /*
-        * Buffer size does not change
-        */
-       if (sizealloc == tp->b_bufsize)
-               goto out;
-       /*
-        * Buffer size is shrinking.
-        * Place excess space in a buffer header taken from the
-        * BQ_EMPTY buffer list and placed on the "most free" list.
-        * If no extra buffer headers are available, leave the
-        * extra space in the present buffer.
-        */
-       if (sizealloc < tp->b_bufsize) {
-               ep = bfreelist[BQ_EMPTY].av_forw;
-               if (ep == &bfreelist[BQ_EMPTY])
-                       goto out;
-               notavail(ep);
-               pagemove(tp->b_un.b_addr + sizealloc, ep->b_un.b_addr,
-                   (int)tp->b_bufsize - sizealloc);
-               ep->b_bufsize = tp->b_bufsize - sizealloc;
-               tp->b_bufsize = sizealloc;
-               ep->b_flags |= B_INVAL;
-               ep->b_bcount = 0;
-               brelse(ep);
-               goto out;
-       }
-       /*
-        * More buffer space is needed. Get it out of buffers on
-        * the "most free" list, placing the empty headers on the
-        * BQ_EMPTY buffer header list.
-        */
-       while (tp->b_bufsize < sizealloc) {
-               take = sizealloc - tp->b_bufsize;
-               bp = getnewbuf();
-               if (take >= bp->b_bufsize)
-                       take = bp->b_bufsize;
-               pagemove(&bp->b_un.b_addr[bp->b_bufsize - take],
-                   &tp->b_un.b_addr[tp->b_bufsize], take);
-               tp->b_bufsize += take;
-               bp->b_bufsize = bp->b_bufsize - take;
-               if (bp->b_bcount > bp->b_bufsize)
-                       bp->b_bcount = bp->b_bufsize;
-               if (bp->b_bufsize <= 0) {
-                       bremhash(bp);
-                       binshash(bp, &bfreelist[BQ_EMPTY]);
-                       bp->b_dev = (dev_t)NODEV;
-                       bp->b_error = 0;
-                       bp->b_flags |= B_INVAL;
-               }
-               brelse(bp);
-       }
-out:
-       tp->b_bcount = size;
-}
-
-/*
- * Release space associated with a buffer.
- */
-bfree(bp)
-       struct buf *bp;
-{
-       /*
-        * This stub is provided to allow the system to reclaim
-        * memory from the buffer pool. Currently we do not migrate
-        * memory between the buffer memory pool and the user memory
-        * pool.
-        */
-       bp->b_bcount = 0;
+       return (allocbuf(bp, size));

 }
 
 /*
 }
 
 /*


@@ -500,13 +433,14 @@ getnewbuf()
        int s;
 
 loop:
        int s;
 
 loop:

-       s = spl6();
+       s = splbio();

        for (dp = &bfreelist[BQ_AGE]; dp > bfreelist; dp--)
                if (dp->av_forw != dp)
                        break;
        if (dp == bfreelist) {          /* no free blocks */
                dp->b_flags |= B_WANTED;
                sleep((caddr_t)dp, PRIBIO+1);
        for (dp = &bfreelist[BQ_AGE]; dp > bfreelist; dp--)
                if (dp->av_forw != dp)
                        break;
        if (dp == bfreelist) {          /* no free blocks */
                dp->b_flags |= B_WANTED;
                sleep((caddr_t)dp, PRIBIO+1);

+               splx(s);

                goto loop;
        }
        splx(s);
                goto loop;
        }
        splx(s);


@@ -517,7 +451,7 @@ loop:
                bwrite(bp);
                goto loop;
        }
                bwrite(bp);
                goto loop;
        }

-       trace(TR_BRELSE, bp->b_dev, bp->b_blkno);
+       trace(TR_BRELSE, pack(bp->b_dev, bp->b_bufsize), bp->b_blkno);

        bp->b_flags = B_BUSY;
        return (bp);
 }
        bp->b_flags = B_BUSY;
        return (bp);
 }


@@ -531,42 +465,30 @@ biowait(bp)
 {
        int s;
 
 {
        int s;
 

-       s = spl6();
+       s = splbio();

        while ((bp->b_flags&B_DONE)==0)
                sleep((caddr_t)bp, PRIBIO);
        splx(s);
        while ((bp->b_flags&B_DONE)==0)
                sleep((caddr_t)bp, PRIBIO);
        splx(s);

-       u.u_error = geterror(bp);
+       if (u.u_error == 0)                     /* XXX */
+               u.u_error = geterror(bp);

 }
 
 /*
 }
 
 /*

- * Mark I/O complete on a buffer. If the header
- * indicates a dirty page push completion, the
- * header is inserted into the ``cleaned'' list
- * to be processed by the pageout daemon. Otherwise
- * release it if I/O is asynchronous, and wake 
- * up anyone waiting for it.
+ * Mark I/O complete on a buffer.
+ * If someone should be called, e.g. the pageout
+ * daemon, do so.  Otherwise, wake up anyone
+ * waiting for it.

  */
 biodone(bp)
        register struct buf *bp;
 {
  */
 biodone(bp)
        register struct buf *bp;
 {

-       register int s;

 
        if (bp->b_flags & B_DONE)
                panic("dup biodone");
        bp->b_flags |= B_DONE;
 
        if (bp->b_flags & B_DONE)
                panic("dup biodone");
        bp->b_flags |= B_DONE;

-       if (bp->b_flags & B_DIRTY) {
-               if (bp->b_flags & B_ERROR)
-                       panic("IO err in push");
-               s = spl6();
-               bp->av_forw = bclnlist;
-               bp->b_bcount = swsize[bp - swbuf];
-               bp->b_pfcent = swpf[bp - swbuf];
-               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 (bp->b_flags & B_CALL) {
+               bp->b_flags &= ~B_CALL;
+               (*bp->b_iodone)(bp);

                return;
        }
        if (bp->b_flags&B_ASYNC)
                return;
        }
        if (bp->b_flags&B_ASYNC)


@@ -591,7 +513,7 @@ blkflush(dev, blkno, size)
        int s;
 
        start = blkno;
        int s;
 
        start = blkno;

-       last = start + (size / DEV_BSIZE) - 1;
+       last = start + btodb(size) - 1;

        dp = BUFHASH(dev, blkno);
 loop:
        for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) {
        dp = BUFHASH(dev, blkno);
 loop:
        for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) {


@@ -599,9 +521,9 @@ loop:
                        continue;
                /* look for overlap */
                if (ep->b_bcount == 0 || ep->b_blkno > last ||
                        continue;
                /* look for overlap */
                if (ep->b_bcount == 0 || ep->b_blkno > last ||

-                   ep->b_blkno + (ep->b_bcount / DEV_BSIZE) <= start)
+                   ep->b_blkno + btodb(ep->b_bcount) <= start)

                        continue;
                        continue;

-               s = spl6();
+               s = splbio();

                if (ep->b_flags&B_BUSY) {
                        ep->b_flags |= B_WANTED;
                        sleep((caddr_t)ep, PRIBIO+1);
                if (ep->b_flags&B_BUSY) {
                        ep->b_flags |= B_WANTED;
                        sleep((caddr_t)ep, PRIBIO+1);


@@ -619,11 +541,10 @@ loop:
 }
 
 /*
 }
 
 /*

- * make sure all write-behind blocks
+ * Make sure all write-behind blocks

  * on dev (or NODEV for all)
  * are flushed out.
  * (from umount and update)
  * on dev (or NODEV for all)
  * are flushed out.
  * (from umount and update)

- * (and temporarily pagein)

  */
 bflush(dev)
        dev_t dev;
  */
 bflush(dev)
        dev_t dev;


@@ -633,7 +554,7 @@ bflush(dev)
        int s;
 
 loop:
        int s;
 
 loop:

-       s = spl6();
+       s = splbio();

        for (flist = bfreelist; flist < &bfreelist[BQ_EMPTY]; flist++)
        for (bp = flist->av_forw; bp != flist; bp = bp->av_forw) {
                if ((bp->b_flags & B_DELWRI) == 0)
        for (flist = bfreelist; flist < &bfreelist[BQ_EMPTY]; flist++)
        for (bp = flist->av_forw; bp != flist; bp = bp->av_forw) {
                if ((bp->b_flags & B_DELWRI) == 0)


@@ -642,6 +563,7 @@ loop:
                        bp->b_flags |= B_ASYNC;
                        notavail(bp);
                        bwrite(bp);
                        bp->b_flags |= B_ASYNC;
                        notavail(bp);
                        bwrite(bp);

+                       splx(s);

                        goto loop;
                }
        }
                        goto loop;
                }
        }


@@ -650,9 +572,7 @@ loop:
 
 /*
  * Pick up the device's error number and pass it to the user;
 
 /*
  * Pick up the device's error number and pass it to the user;

- * if there is an error but the number is 0 set a generalized
- * code.  Actually the latter is always true because devices
- * don't yet return specific errors.
+ * if there is an error but the number is 0 set a generalized code.

  */
 geterror(bp)
        register struct buf *bp;
  */
 geterror(bp)
        register struct buf *bp;