mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-21 11:13:30 +00:00
131 lines
3.4 KiB
C
131 lines
3.4 KiB
C
/*
|
|
* Copyright (c) 1994 John S. Dyson
|
|
* All rights reserved.
|
|
*
|
|
* 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 immediately at the beginning of the file, without modification,
|
|
* 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. Absolutely no warranty of function or purpose is made by the author
|
|
* John S. Dyson.
|
|
* 4. Modifications may be freely made to this file if the above conditions
|
|
* are met.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/bio.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/uio.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_extern.h>
|
|
|
|
int
|
|
physio(dev_t dev, struct uio *uio, int ioflag)
|
|
{
|
|
int i;
|
|
int error;
|
|
int spl;
|
|
caddr_t sa;
|
|
u_int iolen;
|
|
struct buf *bp;
|
|
|
|
/* We cannot trust the device driver to hold Giant for us */
|
|
mtx_lock(&Giant);
|
|
/* Keep the process UPAGES from being swapped. XXX: why ? */
|
|
PHOLD(curproc);
|
|
|
|
bp = getpbuf(NULL);
|
|
sa = bp->b_data;
|
|
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) {
|
|
bp->b_flags = 0;
|
|
if (uio->uio_rw == UIO_READ)
|
|
bp->b_iocmd = BIO_READ;
|
|
else
|
|
bp->b_iocmd = BIO_WRITE;
|
|
bp->b_dev = dev;
|
|
bp->b_iodone = bdone;
|
|
bp->b_data = uio->uio_iov[i].iov_base;
|
|
bp->b_bcount = uio->uio_iov[i].iov_len;
|
|
bp->b_offset = uio->uio_offset;
|
|
bp->b_iooffset = uio->uio_offset;
|
|
bp->b_saveaddr = sa;
|
|
|
|
/* 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;
|
|
|
|
bp->b_blkno = btodb(bp->b_offset);
|
|
|
|
if (uio->uio_segflg == UIO_USERSPACE)
|
|
if (vmapbuf(bp) < 0) {
|
|
error = EFAULT;
|
|
goto doerror;
|
|
}
|
|
|
|
DEV_STRATEGY(bp);
|
|
spl = splbio();
|
|
if (uio->uio_rw == UIO_READ)
|
|
bwait(bp, PRIBIO, "physrd");
|
|
else
|
|
bwait(bp, PRIBIO, "physwr");
|
|
splx(spl);
|
|
|
|
if (uio->uio_segflg == UIO_USERSPACE)
|
|
vunmapbuf(bp);
|
|
iolen = bp->b_bcount - bp->b_resid;
|
|
if (iolen == 0 && !(bp->b_ioflags & BIO_ERROR))
|
|
goto doerror; /* EOF */
|
|
uio->uio_iov[i].iov_len -= iolen;
|
|
uio->uio_iov[i].iov_base =
|
|
(char *)uio->uio_iov[i].iov_base + iolen;
|
|
uio->uio_resid -= iolen;
|
|
uio->uio_offset += iolen;
|
|
if( bp->b_ioflags & BIO_ERROR) {
|
|
error = bp->b_error;
|
|
goto doerror;
|
|
}
|
|
}
|
|
}
|
|
doerror:
|
|
relpbuf(bp, NULL);
|
|
PRELE(curproc);
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|