/*
* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @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. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * 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
* Please see the License for the specific language governing rights and
* limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*-
* Copyright (c) 1982, 1986, 1990, 1993
#include <sys/conf.h>
#include <sys/proc_internal.h>
#include <sys/uio_internal.h>
+#include <kern/assert.h>
+
+int rawread(dev_t dev, struct uio *uio);
+int rawwrite(dev_t dev, struct uio *uio);
int
-physio(strategy, bp, dev, flags, minphys, uio, blocksize)
- void (*strategy)();
- buf_t 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 proc *p = current_proc();
- int error, i, nobuf, todo, iosize;
+ int error, i, buf_allocated, todo, iosize;
+ int orig_bflags = 0;
#if LP64KERN
int64_t done;
#else
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_SEG_IS_USER_SPACE(uio->uio_segflg)) {
+ if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg)) {
if (!useracc(uio_iov_base_at(uio, i),
uio_iov_len_at(uio, i),
(flags == B_READ) ? B_WRITE : B_READ))
return (EFAULT);
}
}
- /* Make sure we have a buffer, creating one if necessary. */
- if (nobuf = (bp == NULL)) {
- bp = buf_alloc((vnode_t)0);
- }
-
- /* [while the buffer is marked busy] */
- while (((error = (int)buf_acquire(bp, 0, 0, 0)) == EAGAIN));
-
- if (error) {
- if (nobuf)
- buf_free(bp);
- return (error);
- }
+ /*
+ * 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);
- /* [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_proc = p;
- buf_seterror(bp, 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 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
*/
for (i = 0; i < uio->uio_iovcnt; i++) {
while (uio_iov_len_at(uio, i) > 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 read/write flag.)
- */
- buf_setflags(bp, B_PHYS | B_RAW | flags);
if ( (iosize = uio_iov_len_at(uio, i)) > MAXPHYSIO_WIRED)
iosize = MAXPHYSIO_WIRED;
+ /*
+ * make sure we're set to issue a fresh I/O
+ * in the right direction
+ */
+ buf_reset(bp, flags);
/* [set up the buffer for a maximum-sized transfer] */
buf_setblkno(bp, uio->uio_offset / blocksize);
buf_setcount(bp, iosize);
// LP64todo - fix this!
- buf_setdataptr(bp, CAST_DOWN(caddr_t, uio_iov_base_at(uio, i)));
+ buf_setdataptr(bp, (uintptr_t)CAST_DOWN(caddr_t, uio_iov_base_at(uio, i)));
/*
- * [call minphys to bound the tranfer size]
+ * [call f_minphys to bound the tranfer size]
* and remember the amount of data to transfer,
* for later comparison.
*/
- (*minphys)(bp);
+ (*f_minphys)(bp);
todo = buf_count(bp);
/*
* in the transfer]
*/
- if(UIO_SEG_IS_USER_SPACE(uio->uio_segflg))
- vslock(CAST_USER_ADDR_T(buf_dataptr(bp)),
- (user_size_t)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 done;
+ }
- /* [call strategy to start the transfer] */
- (*strategy)(bp);
+ /* [call f_strategy to start the transfer] */
+ (*f_strategy)(bp);
/* [wait for the transfer to complete] */
}
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.
- */
-
- buf_clearflags(bp, B_PHYS | B_RAW);
- if (nobuf)
- buf_free(bp);
- else
- {
- buf_drop(bp);
- }
+ if (buf_allocated)
+ buf_free(bp);
+ else
+ buf_setflags(bp, orig_bflags);
return (error);
}
* and return the new count;
*/
u_int
-minphys(bp)
- struct buf *bp;
+minphys(struct buf *bp)
{
buf_setcount(bp, min(MAXPHYS, buf_count(bp)));
/*
* Do a read on a device for a user process.
*/
-rawread(dev, uio)
- dev_t dev;
- struct uio *uio;
+int
+rawread(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;
+int
+rawwrite(dev_t dev, struct uio *uio)
{
return (physio(cdevsw[major(dev)].d_strategy, (struct buf *)NULL,
dev, B_WRITE, minphys, uio, DEV_BSIZE));
projects / apple / xnu.git / blobdiff