diff options
Diffstat (limited to 'sys/kern/kern_physio.c')
| -rw-r--r-- | sys/kern/kern_physio.c | 41 |
1 files changed, 35 insertions, 6 deletions
diff --git a/sys/kern/kern_physio.c b/sys/kern/kern_physio.c index 652c37a696f2..c6cb72fc1e8e 100644 --- a/sys/kern/kern_physio.c +++ b/sys/kern/kern_physio.c @@ -16,7 +16,7 @@ * 4. Modifications may be freely made to this file if the above conditions * are met. * - * $Id: kern_physio.c,v 1.21 1997/08/26 00:15:04 bde Exp $ + * $Id: kern_physio.c,v 1.22 1997/09/02 20:05:40 bde Exp $ */ #include <sys/param.h> @@ -28,6 +28,7 @@ #include <vm/vm_extern.h> static void physwakeup __P((struct buf *bp)); +static struct buf * phygetvpbuf(dev_t dev, int resid); int physio(strategy, bp, dev, rw, minp, uio) @@ -52,7 +53,7 @@ physio(strategy, bp, dev, rw, minp, uio) curproc->p_flag |= P_PHYSIO; /* create and build a buffer header for a transfer */ - bpa = (struct buf *)getpbuf(); + bpa = (struct buf *)phygetvpbuf(dev, uio->uio_resid); if (!bp_alloc) { spl = splbio(); while (bp->b_flags & B_BUSY) { @@ -70,12 +71,12 @@ physio(strategy, bp, dev, rw, minp, uio) */ sa = bpa->b_data; bp->b_proc = curproc; - bp->b_dev = dev; error = bp->b_error = 0; for(i=0;i<uio->uio_iovcnt;i++) { while( uio->uio_iov[i].iov_len) { + bp->b_dev = dev; bp->b_bcount = uio->uio_iov[i].iov_len; bp->b_flags = B_BUSY | B_PHYS | B_CALL | bufflags; bp->b_iodone = physwakeup; @@ -168,18 +169,46 @@ u_int minphys(bp) struct buf *bp; { - u_int maxphys = MAXPHYS; + u_int maxphys = DFLTPHYS; + struct bdevsw *bdsw; + int offset; - if( ((vm_offset_t) bp->b_data) & PAGE_MASK) { - maxphys = MAXPHYS - PAGE_SIZE; + bdsw = cdevsw[major(bp->b_dev)]->d_bdev; + + if (bdsw && bdsw->d_maxio) { + maxphys = bdsw->d_maxio; + } + if (bp->b_kvasize < maxphys) + maxphys = bp->b_kvasize; + + if(((vm_offset_t) bp->b_data) & PAGE_MASK) { + maxphys -= PAGE_SIZE; } if( bp->b_bcount > maxphys) { bp->b_bcount = maxphys; } + return bp->b_bcount; } +struct buf * +phygetvpbuf(dev_t dev, int resid) +{ + struct bdevsw *bdsw; + int maxio; + + bdsw = cdevsw[major(dev)]->d_bdev; + if (bdsw == NULL) + return getpbuf(); + + maxio = bdsw->d_maxio; + if (resid > maxio) + resid = maxio; + + return getpbuf(); +} + int rawread(dev, uio, ioflag) dev_t dev; |