/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*-
* Copyright (c) 1982, 1986, 1990, 1993
#include <sys/param.h>
#include <sys/systm.h>
-#include <sys/buf.h>
+#include <sys/buf_internal.h>
#include <sys/conf.h>
-#include <sys/proc.h>
+#include <sys/proc_internal.h>
+#include <sys/uio_internal.h>
+#include <kern/assert.h>
int
-physio(strategy, bp, dev, flags, minphys, uio, blocksize)
- void (*strategy)();
- struct buf *bp;
- dev_t dev;
- int flags;
- u_int (*minphys)();
- struct uio *uio;
- int blocksize;
+physio( void (*f_strategy)(buf_t),
+ buf_t bp,
+ dev_t dev,
+ int flags,
+ u_int (*f_minphys)(buf_t),
+ struct uio *uio,
+ int blocksize)
{
- struct iovec *iovp;
struct proc *p = current_proc();
- int error, done, i, nobuf, s, todo;
+ int error, i, buf_allocated, todo;
+ size_t iosize;
+ int orig_bflags = 0;
+ int64_t done;
error = 0;
flags &= B_READ | B_WRITE;
+ buf_allocated = 0;
/*
* [check user read/write access to the data buffer]
* we're doing a read, that's a *write* to user-space.
*/
for (i = 0; i < uio->uio_iovcnt; i++) {
- if(uio->uio_segflg != UIO_SYSSPACE) {
- if (!useracc(uio->uio_iov[i].iov_base,
- uio->uio_iov[i].iov_len,
- (flags == B_READ) ? B_WRITE : B_READ))
- return (EFAULT);
+ if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) {
+ user_addr_t base;
+ user_size_t len;
+
+ if (uio_getiov(uio, i, &base, &len) ||
+ !useracc(base,
+ len,
+ (flags == B_READ) ? B_WRITE : B_READ)) {
+ return EFAULT;
+ }
}
}
- /* Make sure we have a buffer, creating one if necessary. */
- if (nobuf = (bp == NULL)) {
-// bp = getphysbuf();
- panic("physio: null buf pointer\n");
- }
-
- /* [raise the processor priority level to splbio;] */
- s = splbio();
-
- /* [while the buffer is marked busy] */
- while (bp->b_flags & B_BUSY) {
- /* [mark the buffer wanted] */
- bp->b_flags |= B_WANTED;
- /* [wait until the buffer is available] */
- tsleep((caddr_t)bp, PRIBIO+1, "physbuf", 0);
+ /*
+ * Make sure we have a buffer, creating one if necessary.
+ */
+ if (bp == NULL) {
+ bp = buf_alloc((vnode_t)0);
+ buf_allocated = 1;
+ } else {
+ orig_bflags = buf_flags(bp);
}
+ /*
+ * at this point we should have a buffer
+ * that is marked BL_BUSY... we either
+ * acquired it via buf_alloc, or it was
+ * passed into us... if it was passed
+ * in, it needs to already be owned by
+ * the caller (i.e. BL_BUSY is set)
+ */
+ assert(bp->b_lflags & BL_BUSY);
- /* Mark it busy, so nobody else will use it. */
- bp->b_flags |= B_BUSY;
-
- /* [lower the priority level] */
- splx(s);
-
- /* [set up the fixed part of the buffer for a transfer] */
+ /*
+ * [set up the fixed part of the buffer for a transfer]
+ */
bp->b_dev = dev;
- bp->b_error = 0;
bp->b_proc = p;
/*
- * [while there are data to transfer and no I/O error]
+ * [mark the buffer busy for physical I/O]
+ * (i.e. set B_PHYS (because it's an I/O to user
+ * memory, and B_RAW, because B_RAW is to be
+ * "Set by physio for raw transfers.", in addition
+ * to the read/write flag.)
+ */
+ buf_setflags(bp, B_PHYS | B_RAW);
+
+ /*
+ * [while there is data to transfer and no I/O error]
* Note that I/O errors are handled with a 'goto' at the bottom
* of the 'while' loop.
*/
- for (i = 0; i < uio->uio_iovcnt; i++) {
- iovp = &uio->uio_iov[i];
- while (iovp->iov_len > 0) {
- /*
- * [mark the buffer busy for physical I/O]
- * (i.e. set B_PHYS (because it's an I/O to user
- * memory, and B_RAW, because B_RAW is to be
- * "Set by physio for raw transfers.", in addition
- * to the "busy" and read/write flag.)
- */
- s = splbio();
- bp->b_flags = B_BUSY | B_PHYS | B_RAW | flags;
- splx(s);
-
- /* [set up the buffer for a maximum-sized transfer] */
- bp->b_blkno = uio->uio_offset / blocksize;
- bp->b_bcount = iovp->iov_len;
- bp->b_data = iovp->iov_base;
-
- /*
- * [call minphys to bound the tranfer size]
- * and remember the amount of data to transfer,
- * for later comparison.
- */
- (*minphys)(bp);
- todo = bp->b_bcount;
+ while (uio_resid(uio) > 0) {
+ iosize = uio_curriovlen(uio);
+ if (iosize > MAXPHYSIO_WIRED) {
+ iosize = MAXPHYSIO_WIRED;
+ }
- /*
- * [lock the part of the user address space involved
- * in the transfer]
- * Beware vmapbuf(); it clobbers b_data and
- * saves it in b_saveaddr. However, vunmapbuf()
- * restores it.
- */
+ /*
+ * make sure we're set to issue a fresh I/O
+ * in the right direction
+ */
+ buf_reset(bp, flags);
- if(uio->uio_segflg != UIO_SYSSPACE)
- vslock(bp->b_data, todo);
-
-#if 0
- vmapbuf(bp, todo);
-#endif /* 0 */
- /* [call strategy to start the transfer] */
- (*strategy)(bp);
+ /* [set up the buffer for a maximum-sized transfer] */
+ buf_setblkno(bp, uio_offset(uio) / blocksize);
+ assert(iosize <= UINT32_MAX);
+ buf_setcount(bp, (uint32_t)iosize);
+ buf_setdataptr(bp, (uintptr_t)CAST_DOWN(caddr_t, uio_curriovbase(uio)));
- /*
- * Note that the raise/wait/lower/get error
- * steps below would be done by biowait(), but
- * we want to unlock the address space before
- * we lower the priority.
- *
- * [raise the priority level to splbio]
- */
- s = splbio();
+ /*
+ * [call f_minphys to bound the tranfer size]
+ * and remember the amount of data to transfer,
+ * for later comparison.
+ */
+ (*f_minphys)(bp);
+ todo = buf_count(bp);
- /* [wait for the transfer to complete] */
- while ((bp->b_flags & B_DONE) == 0)
- tsleep((caddr_t) bp, PRIBIO + 1, "physio", 0);
+ /*
+ * [lock the part of the user address space involved
+ * in the transfer]
+ */
- /*
- * [unlock the part of the address space previously
- * locked]
- */
-#if 0
- vunmapbuf(bp, todo);
-#endif /* 0 */
- if(uio->uio_segflg != UIO_SYSSPACE)
- vsunlock(bp->b_data, todo);
+ if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) {
+ error = vslock(CAST_USER_ADDR_T(buf_dataptr(bp)),
+ (user_size_t)todo);
+ if (error) {
+ goto finished;
+ }
+ }
- /* remember error value (save a splbio/splx pair) */
- if (bp->b_flags & B_ERROR)
- error = (bp->b_error ? bp->b_error : EIO);
+ /* [call f_strategy to start the transfer] */
+ (*f_strategy)(bp);
- /* [lower the priority level] */
- splx(s);
- /*
- * [deduct the transfer size from the total number
- * of data to transfer]
- */
- done = bp->b_bcount - bp->b_resid;
- iovp->iov_len -= done;
- iovp->iov_base += done;
- uio->uio_offset += done;
- uio->uio_resid -= done;
+ /* [wait for the transfer to complete] */
+ error = (int)buf_biowait(bp);
- /*
- * Now, check for an error.
- * Also, handle weird end-of-disk semantics.
- */
- if (error || done < todo)
- goto done;
+ /*
+ * [unlock the part of the address space previously
+ * locked]
+ */
+ if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) {
+ vsunlock(CAST_USER_ADDR_T(buf_dataptr(bp)),
+ (user_size_t)todo,
+ (flags & B_READ));
}
- }
-done:
- /*
- * [clean up the state of the buffer]
- * Remember if somebody wants it, so we can wake them up below.
- * Also, if we had to steal it, give it back.
- */
- s = splbio();
- bp->b_flags &= ~(B_BUSY | B_PHYS | B_RAW);
-#if 0
- if (nobuf)
- putphysbuf(bp);
+ /*
+ * [deduct the transfer size from the total number
+ * of data to transfer]
+ */
+ done = buf_count(bp) - buf_resid(bp);
+ assert(0 <= done && done <= UINT32_MAX);
+ uio_update(uio, (user_size_t)done);
- else
-#endif /* 0 */
- {
/*
- * [if another process is waiting for the raw I/O buffer,
- * wake up processes waiting to do physical I/O;
+ * Now, check for an error.
+ * Also, handle weird end-of-disk semantics.
*/
- if (bp->b_flags & B_WANTED) {
- bp->b_flags &= ~B_WANTED;
- wakeup(bp);
+ if (error || done < todo) {
+ goto finished;
}
}
- splx(s);
- return (error);
+finished:
+ if (buf_allocated) {
+ buf_free(bp);
+ } else {
+ buf_setflags(bp, orig_bflags);
+ }
+
+ return error;
}
/*
* Leffler, et al., says on p. 231:
* "The minphys() routine is called by physio() to adjust the
* size of each I/O transfer before the latter is passed to
- * the strategy routine..."
+ * the strategy routine..."
*
* so, just adjust the buffer's count accounting to MAXPHYS here,
* and return the new count;
*/
u_int
-minphys(bp)
- struct buf *bp;
-{
-
- bp->b_bcount = min(MAXPHYS, bp->b_bcount);
- return bp->b_bcount;
-}
-
-/*
- * Do a read on a device for a user process.
- */
-rawread(dev, uio)
- dev_t dev;
- struct uio *uio;
-{
- return (physio(cdevsw[major(dev)].d_strategy, (struct buf *)NULL,
- dev, B_READ, minphys, uio, DEV_BSIZE));
-}
-
-/*
- * Do a write on a device for a user process.
- */
-rawwrite(dev, uio)
- dev_t dev;
- struct uio *uio;
+minphys(struct buf *bp)
{
- return (physio(cdevsw[major(dev)].d_strategy, (struct buf *)NULL,
- dev, B_WRITE, minphys, uio, DEV_BSIZE));
+ buf_setcount(bp, min(MAXPHYS, buf_count(bp)));
+ return buf_count(bp);
}
projects / apple / xnu.git / blobdiff