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 * 4. 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: src/sys/amd64/amd64/uio_machdep.c,v 1.6 2005/01/05 20:17:20 imp Exp $");
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 */
58 int
59 uiomove_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;
65 size_t cnt;
66 int error = 0;
67 int save = 0;
68
69 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
70 ("uiomove_fromphys: mode"));
71 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
72 ("uiomove_fromphys proc"));
73 save = td->td_pflags & TDP_DEADLKTREAT;
74 td->td_pflags |= TDP_DEADLKTREAT;
75 while (n > 0 && uio->uio_resid) {
76 iov = uio->uio_iov;
77 cnt = iov->iov_len;
78 if (cnt == 0) {
79 uio->uio_iov++;
80 uio->uio_iovcnt--;
81 continue;
82 }
83 if (cnt > n)
84 cnt = n;
85 page_offset = offset & PAGE_MASK;
86 cnt = min(cnt, PAGE_SIZE - page_offset);
87 cp = (char *)PHYS_TO_DMAP(ma[offset >> PAGE_SHIFT]->phys_addr) +
88 page_offset;
89 switch (uio->uio_segflg) {
90 case UIO_USERSPACE:
91 if (ticks - PCPU_GET(switchticks) >= hogticks)
92 uio_yield();
93 if (uio->uio_rw == UIO_READ)
94 error = copyout(cp, iov->iov_base, cnt);
95 else
96 error = copyin(iov->iov_base, cp, cnt);
97 if (error)
98 goto out;
99 break;
100 case UIO_SYSSPACE:
101 if (uio->uio_rw == UIO_READ)
102 bcopy(cp, iov->iov_base, cnt);
103 else
104 bcopy(iov->iov_base, cp, cnt);
105 break;
106 case UIO_NOCOPY:
107 break;
108 }
109 iov->iov_base = (char *)iov->iov_base + cnt;
110 iov->iov_len -= cnt;
111 uio->uio_resid -= cnt;
112 uio->uio_offset += cnt;
113 offset += cnt;
114 n -= cnt;
115 }
116 out:
117 if (save == 0)
118 td->td_pflags &= ~TDP_DEADLKTREAT;
119 return (error);
120 }
121 Cache object: 9d3b4554402e97be3ed9d64e8afc9fbf
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