clocal, nonblock, other carrier related stuff

[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 7967340..fbaa042 100644 (file)
--- a/usr/src/sys/kern/vfs_cluster.c
+++ b/usr/src/sys/kern/vfs_cluster.c
@@ -1,35 +1,52 @@
-/*     vfs_cluster.c   6.2     84/01/03        */
+/*
+ * 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.
+ *
+ *     @(#)vfs_cluster.c       7.4 (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"

 
 

-#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/vm.h"
-#include "../h/trace.h"
+#include "machine/pte.h"

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

+#ifdef SECSIZE
+bread(dev, blkno, size, secsize)
+#else SECSIZE

 bread(dev, blkno, size)
 bread(dev, blkno, size)

+#endif SECSIZE

        dev_t dev;
        daddr_t blkno;
        int size;
        dev_t dev;
        daddr_t blkno;
        int size;

+#ifdef SECSIZE
+       long secsize;
+#endif SECSIZE

 {
        register struct buf *bp;
 
        if (size == 0)
                panic("bread: size 0");
 {
        register struct buf *bp;
 
        if (size == 0)
                panic("bread: size 0");

+#ifdef SECSIZE
+       bp = getblk(dev, blkno, size, secsize);
+#else SECSIZE

        bp = getblk(dev, blkno, size);
        bp = getblk(dev, blkno, size);

-       if (bp->b_flags&B_DONE) {
+#endif SECSIZE
+       if (bp->b_flags&(B_DONE|B_DELWRI)) {

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

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

        }
        bp->b_flags |= B_READ;
        if (bp->b_bcount > bp->b_bufsize)
        }
        bp->b_flags |= B_READ;
        if (bp->b_bcount > bp->b_bufsize)


@@ -38,7 +55,7 @@ bread(dev, blkno, size)
        trace(TR_BREADMISS, pack(dev, size), blkno);
        u.u_ru.ru_inblock++;            /* pay for read */
        biowait(bp);
        trace(TR_BREADMISS, pack(dev, size), blkno);
        u.u_ru.ru_inblock++;            /* pay for read */
        biowait(bp);

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

 }
 
 /*
 }
 
 /*


@@ -46,9 +63,16 @@ bread(dev, blkno, size)
  * read-ahead block (which is not allocated to the caller)
  */
 struct buf *
  * read-ahead block (which is not allocated to the caller)
  */
 struct buf *

+#ifdef SECSIZE
+breada(dev, blkno, size, secsize, rablkno, rabsize)
+#else SECSIZE

 breada(dev, blkno, size, rablkno, rabsize)
 breada(dev, blkno, size, rablkno, rabsize)

+#endif SECSIZE

        dev_t dev;
        daddr_t blkno; int size;
        dev_t dev;
        daddr_t blkno; int size;

+#ifdef SECSIZE
+       long secsize;
+#endif SECSIZE

        daddr_t rablkno; int rabsize;
 {
        register struct buf *bp, *rabp;
        daddr_t rablkno; int rabsize;
 {
        register struct buf *bp, *rabp;


@@ -60,8 +84,12 @@ breada(dev, blkno, size, rablkno, rabsize)
         * for a cache hit).
         */
        if (!incore(dev, blkno)) {
         * for a cache hit).
         */
        if (!incore(dev, blkno)) {

+#ifdef SECSIZE
+               bp = getblk(dev, blkno, size, secsize);
+#else SECSIZE

                bp = getblk(dev, blkno, size);
                bp = getblk(dev, blkno, size);

-               if ((bp->b_flags&B_DONE) == 0) {
+#endif SECSIZE
+               if ((bp->b_flags&(B_DONE|B_DELWRI)) == 0) {

                        bp->b_flags |= B_READ;
                        if (bp->b_bcount > bp->b_bufsize)
                                panic("breada");
                        bp->b_flags |= B_READ;
                        if (bp->b_bcount > bp->b_bufsize)
                                panic("breada");


@@ -77,8 +105,12 @@ breada(dev, blkno, size, rablkno, rabsize)
         * on it also (as above).
         */
        if (rablkno && !incore(dev, rablkno)) {
         * on it also (as above).
         */
        if (rablkno && !incore(dev, rablkno)) {

+#ifdef SECSIZE
+               rabp = getblk(dev, rablkno, rabsize, secsize);
+#else SECSIZE

                rabp = getblk(dev, rablkno, rabsize);
                rabp = getblk(dev, rablkno, rabsize);

-               if (rabp->b_flags & B_DONE) {
+#endif SECSIZE
+               if (rabp->b_flags & (B_DONE|B_DELWRI)) {

                        brelse(rabp);
                        trace(TR_BREADHITRA, pack(dev, rabsize), blkno);
                } else {
                        brelse(rabp);
                        trace(TR_BREADHITRA, pack(dev, rabsize), blkno);
                } else {


@@ -97,7 +129,11 @@ breada(dev, blkno, size, rablkno, rabsize)
         * above, and just wait for it.
         */
        if (bp == NULL)
         * above, and just wait for it.
         */
        if (bp == NULL)

+#ifdef SECSIZE
+               return (bread(dev, blkno, size, secsize));
+#else SECSIZE

                return (bread(dev, blkno, size));
                return (bread(dev, blkno, size));

+#endif SECSIZE

        biowait(bp);
        return (bp);
 }
        biowait(bp);
        return (bp);
 }


@@ -143,12 +179,10 @@ bwrite(bp)
 bdwrite(bp)
        register struct buf *bp;
 {
 bdwrite(bp)
        register struct buf *bp;
 {

-       register int flags;

 
        if ((bp->b_flags&B_DELWRI) == 0)
                u.u_ru.ru_oublock++;            /* noone paid yet */
 
        if ((bp->b_flags&B_DELWRI) == 0)
                u.u_ru.ru_oublock++;            /* noone paid yet */

-       flags = bdevsw[major(bp->b_dev)].d_flags;
-       if(flags & B_TAPE)
+       if (bdevsw[major(bp->b_dev)].d_flags & B_TAPE)

                bawrite(bp);
        else {
                bp->b_flags |= B_DELWRI | B_DONE;
                bawrite(bp);
        else {
                bp->b_flags |= B_DELWRI | B_DONE;


@@ -196,7 +230,7 @@ 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];


@@ -238,14 +272,25 @@ incore(dev, blkno)
 }
 
 struct buf *
 }
 
 struct buf *

+#ifdef SECSIZE
+baddr(dev, blkno, size, secsize)
+#else SECSIZE

 baddr(dev, blkno, size)
 baddr(dev, blkno, size)

+#endif SECSIZE

        dev_t dev;
        daddr_t blkno;
        int size;
        dev_t dev;
        daddr_t blkno;
        int size;

+#ifdef SECSIZE
+       long secsize;
+#endif SECSIZE

 {
 
        if (incore(dev, blkno))
 {
 
        if (incore(dev, blkno))

+#ifdef SECSIZE
+               return (bread(dev, blkno, size, secsize));
+#else SECSIZE

                return (bread(dev, blkno, size));
                return (bread(dev, blkno, size));

+#endif SECSIZE

        return (0);
 }
 
        return (0);
 }
 


@@ -254,21 +299,45 @@ baddr(dev, blkno, size)
  * block is already associated, return it; otherwise search
  * for the oldest non-busy buffer and reassign it.
  *
  * block is already associated, return it; otherwise search
  * for the oldest non-busy buffer and reassign it.
  *

+ * If we find the buffer, but it is dirty (marked DELWRI) and
+ * its size is changing, we must write it out first. When the
+ * buffer is shrinking, the write is done by brealloc to avoid
+ * losing the unwritten data. When the buffer is growing, the
+ * write is done by getblk, so that bread will not read stale
+ * disk data over the modified data in the buffer.
+ *

  * We use splx here because this routine may be called
  * on the interrupt stack during a dump, and we don't
  * want to lower the ipl back to 0.
  */
 struct buf *
  * We use splx here because this routine may be called
  * on the interrupt stack during a dump, and we don't
  * want to lower the ipl back to 0.
  */
 struct buf *

+#ifdef SECSIZE
+getblk(dev, blkno, size, secsize)
+#else SECSIZE

 getblk(dev, blkno, size)
 getblk(dev, blkno, size)

+#endif SECSIZE

        dev_t dev;
        daddr_t blkno;
        int size;
        dev_t dev;
        daddr_t blkno;
        int size;

+#ifdef SECSIZE
+       long secsize;
+#endif SECSIZE

 {
        register struct buf *bp, *dp;
        int s;
 
 {
        register struct buf *bp, *dp;
        int s;
 

-       if ((unsigned)blkno >= 1 << (sizeof(int)*NBBY-PGSHIFT)) /* XXX */
-               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


@@ -280,7 +349,7 @@ 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);


@@ -289,10 +358,19 @@ loop:
                }
                splx(s);
                notavail(bp);
                }
                splx(s);
                notavail(bp);

-               if (brealloc(bp, size) == 0)
+               if (bp->b_bcount != size) {
+                       if (bp->b_bcount < size && (bp->b_flags&B_DELWRI)) {
+                               bp->b_flags &= ~B_ASYNC;
+                               bwrite(bp);
+                               goto loop;
+                       }
+                       if (brealloc(bp, size) == 0)
+                               goto loop;
+               }
+               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");


@@ -301,11 +379,14 @@ loop:
        bremhash(bp);
        binshash(bp, dp);
        bp->b_dev = dev;
        bremhash(bp);
        binshash(bp, dp);
        bp->b_dev = dev;

+#ifdef SECSIZE
+       bp->b_blksize = secsize;
+#endif SECSIZE

        bp->b_blkno = blkno;
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;
        bp->b_blkno = blkno;
        bp->b_error = 0;
        if (brealloc(bp, size) == 0)
                goto loop;

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

 }
 
 /*
 }
 
 /*


@@ -318,6 +399,8 @@ 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;


@@ -326,10 +409,13 @@ loop:
        flist = &bfreelist[BQ_AGE];
        binshash(bp, flist);
        bp->b_dev = (dev_t)NODEV;
        flist = &bfreelist[BQ_AGE];
        binshash(bp, flist);
        bp->b_dev = (dev_t)NODEV;

+#ifdef SECSIZE
+       bp->b_blksize = DEV_BSIZE;
+#endif SECSIZE

        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);

 }
 
 /*
 }
 
 /*


@@ -346,7 +432,7 @@ brealloc(bp, size)
        int s;
 
        /*
        int s;
 
        /*

-        * First need to make sure that all overlaping previous I/O
+        * First need to make sure that all overlapping previous I/O

         * is dispatched with.
         */
        if (size == bp->b_bcount)
         * is dispatched with.
         */
        if (size == bp->b_bcount)


@@ -374,7 +460,11 @@ 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;

+#ifdef SECSIZE
+       last = start + size/bp->b_blksize - 1;
+#else SECSIZE

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

+#endif SECSIZE

        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) {


@@ -382,9 +472,13 @@ 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 ||

+#ifdef SECSIZE
+                   ep->b_blkno + ep->b_bcount/ep->b_blksize <= start)
+#else SECSIZE

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

+#endif SECSIZE

                        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);


@@ -415,7 +509,7 @@ 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;
        for (dp = &bfreelist[BQ_AGE]; dp > bfreelist; dp--)
                if (dp->av_forw != dp)
                        break;


@@ -447,7 +541,7 @@ 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);


@@ -483,11 +577,21 @@ biodone(bp)
 
 /*
  * Insure that no part of a specified block is in an incore buffer.
 
 /*
  * Insure that no part of a specified block is in an incore buffer.

+#ifdef SECSIZE
+ * "size" is given in device blocks (the units of b_blkno).
+#endif SECSIZE
+#ifdef SECSIZE
+ * "size" is given in device blocks (the units of b_blkno).
+#endif SECSIZE

  */
 blkflush(dev, blkno, size)
        dev_t dev;
        daddr_t blkno;
  */
 blkflush(dev, blkno, size)
        dev_t dev;
        daddr_t blkno;

+#ifdef SECSIZE
+       int size;
+#else SECSIZE

        long size;
        long size;

+#endif SECSIZE

 {
        register struct buf *ep;
        struct buf *dp;
 {
        register struct buf *ep;
        struct buf *dp;


@@ -495,7 +599,11 @@ blkflush(dev, blkno, size)
        int s;
 
        start = blkno;
        int s;
 
        start = blkno;

+#ifdef SECSIZE
+       last = start + size - 1;
+#else SECSIZE

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

+#endif SECSIZE

        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) {


@@ -503,9 +611,13 @@ 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 ||

+#ifdef SECSIZE
+                   ep->b_blkno + ep->b_bcount / ep->b_blksize <= start)
+#else SECSIZE

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

+#endif SECSIZE

                        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);


@@ -536,7 +648,7 @@ 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)


@@ -554,9 +666,7 @@ 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;