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9626b608de
<sys/bio.h>. <sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall not be made a nested include according to bdes teachings on the subject of nested includes. Diskdrivers and similar stuff below specfs::strategy() should no longer need to include <sys/buf.> unless they need caching of data. Still a few bogus uses of struct buf to track down. Repocopy by: peter
139 lines
3.5 KiB
C
139 lines
3.5 KiB
C
/*
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* Copyright (c) 1994 John S. Dyson
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice immediately at the beginning of the file, without modification,
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* this list of conditions, and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Absolutely no warranty of function or purpose is made by the author
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* John S. Dyson.
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* 4. Modifications may be freely made to this file if the above conditions
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* are met.
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*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/bio.h>
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#include <sys/buf.h>
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#include <sys/conf.h>
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#include <sys/proc.h>
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#include <sys/uio.h>
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#include <vm/vm.h>
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#include <vm/vm_extern.h>
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static void
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physwakeup(struct buf *bp)
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{
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wakeup((caddr_t) bp);
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}
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int
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physio(dev_t dev, struct uio *uio, int ioflag)
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{
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int i;
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int error;
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int spl;
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caddr_t sa;
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off_t blockno;
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u_int iolen;
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struct buf *bp;
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/* Keep the process UPAGES from being swapped. XXX: why ? */
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PHOLD(curproc);
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bp = getpbuf(NULL);
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sa = bp->b_data;
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error = bp->b_error = 0;
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/* XXX: sanity check */
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if(dev->si_iosize_max < PAGE_SIZE) {
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printf("WARNING: %s si_iosize_max=%d, using DFLTPHYS.\n",
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devtoname(dev), dev->si_iosize_max);
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dev->si_iosize_max = DFLTPHYS;
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}
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for (i = 0; i < uio->uio_iovcnt; i++) {
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while (uio->uio_iov[i].iov_len) {
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bp->b_flags = B_PHYS;
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if (uio->uio_rw == UIO_READ)
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bp->b_iocmd = BIO_READ;
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else
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bp->b_iocmd = BIO_WRITE;
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bp->b_dev = dev;
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bp->b_iodone = physwakeup;
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bp->b_data = uio->uio_iov[i].iov_base;
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bp->b_bcount = uio->uio_iov[i].iov_len;
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bp->b_offset = uio->uio_offset;
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bp->b_saveaddr = sa;
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/* Don't exceed drivers iosize limit */
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if (bp->b_bcount > dev->si_iosize_max)
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bp->b_bcount = dev->si_iosize_max;
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/*
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* Make sure the pbuf can map the request
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* XXX: The pbuf has kvasize = MAXPHYS so a request
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* XXX: larger than MAXPHYS - PAGE_SIZE must be
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* XXX: page aligned or it will be fragmented.
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*/
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iolen = ((vm_offset_t) bp->b_data) & PAGE_MASK;
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if ((bp->b_bcount + iolen) > bp->b_kvasize) {
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bp->b_bcount = bp->b_kvasize;
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if (iolen != 0)
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bp->b_bcount -= PAGE_SIZE;
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}
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bp->b_bufsize = bp->b_bcount;
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blockno = bp->b_offset >> DEV_BSHIFT;
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if ((daddr_t)blockno != blockno) {
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error = EINVAL; /* blockno overflow */
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goto doerror;
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}
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bp->b_blkno = blockno;
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if (uio->uio_segflg == UIO_USERSPACE) {
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if (!useracc(bp->b_data, bp->b_bufsize,
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bp->b_iocmd == BIO_READ ?
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VM_PROT_WRITE : VM_PROT_READ)) {
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error = EFAULT;
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goto doerror;
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}
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vmapbuf(bp);
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}
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DEV_STRATEGY(bp, 0);
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spl = splbio();
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while ((bp->b_flags & B_DONE) == 0)
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tsleep((caddr_t)bp, PRIBIO, "physstr", 0);
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splx(spl);
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if (uio->uio_segflg == UIO_USERSPACE)
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vunmapbuf(bp);
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iolen = bp->b_bcount - bp->b_resid;
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if (iolen == 0 && !(bp->b_ioflags & BIO_ERROR))
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goto doerror; /* EOF */
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uio->uio_iov[i].iov_len -= iolen;
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uio->uio_iov[i].iov_base += iolen;
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uio->uio_resid -= iolen;
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uio->uio_offset += iolen;
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if( bp->b_ioflags & BIO_ERROR) {
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error = bp->b_error;
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goto doerror;
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}
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}
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}
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doerror:
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relpbuf(bp, NULL);
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PRELE(curproc);
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return (error);
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}
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