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-rw-r--r--sys/kern/kern_physio.c175
-rw-r--r--sys/sys/bio.h8
-rw-r--r--sys/sys/buf.h8
3 files changed, 60 insertions, 131 deletions
diff --git a/sys/kern/kern_physio.c b/sys/kern/kern_physio.c
index 45ecf87..6a4034e 100644
--- a/sys/kern/kern_physio.c
+++ b/sys/kern/kern_physio.c
@@ -29,175 +29,108 @@
#include <vm/vm.h>
#include <vm/vm_extern.h>
-static void physwakeup __P((struct buf *bp));
-
-int
-physread(dev_t dev, struct uio *uio, int ioflag)
-{
- return(physio(NULL, dev, 1, minphys, uio));
-}
-
-int
-physwrite(dev_t dev, struct uio *uio, int ioflag)
+static void
+physwakeup(struct buf *bp)
{
- return(physio(NULL, dev, 0, minphys, uio));
+ wakeup((caddr_t) bp);
+ bp->b_flags &= ~B_CALL;
}
int
-physio(bp, dev, rw, minp, uio)
- struct buf *bp;
- dev_t dev;
- int rw;
- u_int (*minp) __P((struct buf *bp));
- struct uio *uio;
+physio(dev_t dev, struct uio *uio, int ioflag)
{
int i;
- int bufflags = rw?B_READ:0;
int error;
int spl;
caddr_t sa;
off_t blockno;
- int bp_alloc = (bp == 0);
- struct buf *bpa;
+ u_int iolen;
+ struct buf *bp;
- /*
- * Keep the process UPAGES from being swapped. (XXX for performance?)
- */
+ /* Keep the process UPAGES from being swapped. XXX: why ? */
PHOLD(curproc);
- /* create and build a buffer header for a transfer */
- bpa = getpbuf(NULL);
- if (!bp_alloc)
- BUF_LOCK(bp, LK_EXCLUSIVE);
- else
- bp = bpa;
-
- /*
- * get a copy of the kva from the physical buffer
- */
- sa = bpa->b_data;
+ bp = getpbuf(NULL);
+ sa = bp->b_data;
error = bp->b_error = 0;
+ /* XXX: sanity check */
+ if(dev->si_iosize_max < PAGE_SIZE) {
+ printf("WARNING: %s si_iosize_max=%d, using DFLTPHYS.\n",
+ devtoname(dev), dev->si_iosize_max);
+ dev->si_iosize_max = DFLTPHYS;
+ }
+
for (i = 0; i < uio->uio_iovcnt; i++) {
while (uio->uio_iov[i].iov_len) {
-
+ if (uio->uio_rw == UIO_READ)
+ bp->b_flags = B_PHYS | B_CALL | B_READ;
+ else
+ bp->b_flags = B_PHYS | B_CALL | B_WRITE;
bp->b_dev = dev;
- bp->b_bcount = uio->uio_iov[i].iov_len;
- bp->b_flags = B_PHYS | B_CALL | bufflags;
bp->b_iodone = physwakeup;
bp->b_data = uio->uio_iov[i].iov_base;
- bp->b_bcount = minp( bp);
- if( minp != minphys)
- bp->b_bcount = minphys( bp);
- bp->b_bufsize = bp->b_bcount;
- /*
- * pass in the kva from the physical buffer
- * for the temporary kernel mapping.
- */
+ bp->b_bcount = uio->uio_iov[i].iov_len;
+ bp->b_offset = uio->uio_offset;
bp->b_saveaddr = sa;
- blockno = uio->uio_offset >> DEV_BSHIFT;
+
+ /* Don't exceed drivers iosize limit */
+ if (bp->b_bcount > dev->si_iosize_max)
+ bp->b_bcount = dev->si_iosize_max;
+
+ /*
+ * Make sure the pbuf can map the request
+ * XXX: The pbuf has kvasize = MAXPHYS so a request
+ * XXX: larger than MAXPHYS - PAGE_SIZE must be
+ * XXX: page aligned or it will be fragmented.
+ */
+ iolen = ((vm_offset_t) bp->b_data) & PAGE_MASK;
+ if ((bp->b_bcount + iolen) > bp->b_kvasize) {
+ bp->b_bcount = bp->b_kvasize;
+ if (iolen != 0)
+ bp->b_bcount -= PAGE_SIZE;
+ }
+ bp->b_bufsize = bp->b_bcount;
+
+ blockno = bp->b_offset >> DEV_BSHIFT;
if ((daddr_t)blockno != blockno) {
- error = EINVAL;
+ error = EINVAL; /* blockno overflow */
goto doerror;
}
bp->b_blkno = blockno;
- bp->b_offset = uio->uio_offset;
if (uio->uio_segflg == UIO_USERSPACE) {
- if (rw && !useracc(bp->b_data, bp->b_bufsize, B_WRITE)) {
- error = EFAULT;
- goto doerror;
- }
- if (!rw && !useracc(bp->b_data, bp->b_bufsize, B_READ)) {
+ if (!useracc(bp->b_data, bp->b_bufsize,
+ bp->b_flags & B_READ)) {
error = EFAULT;
goto doerror;
}
-
- /* bring buffer into kernel space */
vmapbuf(bp);
}
- /* perform transfer */
BUF_STRATEGY(bp, 0);
-
spl = splbio();
while ((bp->b_flags & B_DONE) == 0)
tsleep((caddr_t)bp, PRIBIO, "physstr", 0);
splx(spl);
- /* release mapping into kernel space */
if (uio->uio_segflg == UIO_USERSPACE)
vunmapbuf(bp);
-
- /*
- * update the uio data
- */
- {
- int iolen = bp->b_bcount - bp->b_resid;
-
- if (iolen == 0 && !(bp->b_flags & B_ERROR))
- goto doerror; /* EOF */
- uio->uio_iov[i].iov_len -= iolen;
- uio->uio_iov[i].iov_base += iolen;
- uio->uio_resid -= iolen;
- uio->uio_offset += iolen;
- }
-
- /*
- * check for an error
- */
+ iolen = bp->b_bcount - bp->b_resid;
+ if (iolen == 0 && !(bp->b_flags & B_ERROR))
+ goto doerror; /* EOF */
+ uio->uio_iov[i].iov_len -= iolen;
+ uio->uio_iov[i].iov_base += iolen;
+ uio->uio_resid -= iolen;
+ uio->uio_offset += iolen;
if( bp->b_flags & B_ERROR) {
error = bp->b_error;
goto doerror;
}
}
}
-
-
doerror:
- relpbuf(bpa, NULL);
- if (!bp_alloc) {
- bp->b_flags &= ~B_PHYS;
- BUF_UNLOCK(bp);
- }
- /*
- * Allow the process UPAGES to be swapped again.
- */
+ relpbuf(bp, NULL);
PRELE(curproc);
-
return (error);
}
-
-u_int
-minphys(bp)
- struct buf *bp;
-{
- u_int maxphys;
-
- maxphys = bp->b_dev->si_iosize_max;
- if(!maxphys) {
- printf("WARNING: %s maxphys = 0 ??\n", devtoname(bp->b_dev));
- maxphys = DFLTPHYS;
- bp->b_dev->si_iosize_max = DFLTPHYS;
- }
- if (bp->b_kvasize && (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;
-}
-
-static void
-physwakeup(bp)
- struct buf *bp;
-{
- wakeup((caddr_t) bp);
- bp->b_flags &= ~B_CALL;
-}
diff --git a/sys/sys/bio.h b/sys/sys/bio.h
index ae4dbfd..05e9863 100644
--- a/sys/sys/bio.h
+++ b/sys/sys/bio.h
@@ -480,11 +480,9 @@ int cluster_read __P((struct vnode *, u_quad_t, daddr_t, long,
struct ucred *, long, int, struct buf **));
int cluster_wbuild __P((struct vnode *, long, daddr_t, int));
void cluster_write __P((struct buf *, u_quad_t));
-int physio __P((struct buf *, dev_t, int, u_int (*)(struct buf *),
- struct uio *));
-int physread __P((dev_t dev, struct uio *uio, int ioflag));
-int physwrite __P((dev_t dev, struct uio *uio, int ioflag));
-u_int minphys __P((struct buf *));
+int physio __P((dev_t dev, struct uio *uio, int ioflag));
+#define physread physio
+#define physwrite physio
void vfs_bio_set_validclean __P((struct buf *, int base, int size));
void vfs_bio_clrbuf __P((struct buf *));
void vfs_busy_pages __P((struct buf *, int clear_modify));
diff --git a/sys/sys/buf.h b/sys/sys/buf.h
index ae4dbfd..05e9863 100644
--- a/sys/sys/buf.h
+++ b/sys/sys/buf.h
@@ -480,11 +480,9 @@ int cluster_read __P((struct vnode *, u_quad_t, daddr_t, long,
struct ucred *, long, int, struct buf **));
int cluster_wbuild __P((struct vnode *, long, daddr_t, int));
void cluster_write __P((struct buf *, u_quad_t));
-int physio __P((struct buf *, dev_t, int, u_int (*)(struct buf *),
- struct uio *));
-int physread __P((dev_t dev, struct uio *uio, int ioflag));
-int physwrite __P((dev_t dev, struct uio *uio, int ioflag));
-u_int minphys __P((struct buf *));
+int physio __P((dev_t dev, struct uio *uio, int ioflag));
+#define physread physio
+#define physwrite physio
void vfs_bio_set_validclean __P((struct buf *, int base, int size));
void vfs_bio_clrbuf __P((struct buf *));
void vfs_busy_pages __P((struct buf *, int clear_modify));
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