1/*-
2 * Copyright (c) 2004 Alan L. Cox <alc@cs.rice.edu>
3 * Copyright (c) 1982, 1986, 1991, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 * (c) UNIX System Laboratories, Inc.
6 * All or some portions of this file are derived from material licensed
7 * to the University of California by American Telephone and Telegraph
8 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
9 * the permission of UNIX System Laboratories, Inc.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 *	@(#)kern_subr.c	8.3 (Berkeley) 1/21/94
36 */
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41#include <sys/param.h>
42#include <sys/kernel.h>
43#include <sys/lock.h>
44#include <sys/mutex.h>
45#include <sys/proc.h>
46#include <sys/systm.h>
47#include <sys/uio.h>
48
49#include <vm/vm.h>
50#include <vm/vm_page.h>
51
52#include <machine/vmparam.h>
53
54/*
55 * Implement uiomove(9) from physical memory using the direct map to
56 * avoid the creation and destruction of ephemeral mappings.
57 */
58int
59uiomove_fromphys(vm_page_t ma[], vm_offset_t offset, int n, struct uio *uio)
60{
61	struct thread *td = curthread;
62	struct iovec *iov;
63	void *cp;
64	vm_offset_t page_offset, vaddr;
65	size_t cnt;
66	int error = 0;
67	int save = 0;
68	boolean_t mapped;
69
70	KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
71	    ("uiomove_fromphys: mode"));
72	KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
73	    ("uiomove_fromphys proc"));
74	save = td->td_pflags & TDP_DEADLKTREAT;
75	td->td_pflags |= TDP_DEADLKTREAT;
76	mapped = FALSE;
77	while (n > 0 && uio->uio_resid) {
78		iov = uio->uio_iov;
79		cnt = iov->iov_len;
80		if (cnt == 0) {
81			uio->uio_iov++;
82			uio->uio_iovcnt--;
83			continue;
84		}
85		if (cnt > n)
86			cnt = n;
87		page_offset = offset & PAGE_MASK;
88		cnt = min(cnt, PAGE_SIZE - page_offset);
89		if (uio->uio_segflg != UIO_NOCOPY) {
90			mapped = pmap_map_io_transient(
91			    &ma[offset >> PAGE_SHIFT], &vaddr, 1, TRUE);
92			cp = (char *)vaddr + page_offset;
93		}
94		switch (uio->uio_segflg) {
95		case UIO_USERSPACE:
96			maybe_yield();
97			if (uio->uio_rw == UIO_READ)
98				error = copyout(cp, iov->iov_base, cnt);
99			else
100				error = copyin(iov->iov_base, cp, cnt);
101			if (error)
102				goto out;
103			break;
104		case UIO_SYSSPACE:
105			if (uio->uio_rw == UIO_READ)
106				bcopy(cp, iov->iov_base, cnt);
107			else
108				bcopy(iov->iov_base, cp, cnt);
109			break;
110		case UIO_NOCOPY:
111			break;
112		}
113		if (__predict_false(mapped)) {
114			pmap_unmap_io_transient(&ma[offset >> PAGE_SHIFT],
115			    &vaddr, 1, TRUE);
116			mapped = FALSE;
117		}
118		iov->iov_base = (char *)iov->iov_base + cnt;
119		iov->iov_len -= cnt;
120		uio->uio_resid -= cnt;
121		uio->uio_offset += cnt;
122		offset += cnt;
123		n -= cnt;
124	}
125out:
126	if (__predict_false(mapped)) {
127		panic("ARM64TODO: uiomove_fromphys");
128		pmap_unmap_io_transient(&ma[offset >> PAGE_SHIFT], &vaddr, 1,
129		    TRUE);
130	}
131	if (save == 0)
132		td->td_pflags &= ~TDP_DEADLKTREAT;
133	return (error);
134}
135