Subversion Repositories HelenOS

Rev

Rev 2071 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1288 jermar 1 
/*
2071 jermar 2 
 * Copyright (c) 2006 Jakub Jermar
1288 jermar 3 
 * All rights reserved.
4 
 *
5 
 * Redistribution and use in source and binary forms, with or without
6 
 * modification, are permitted provided that the following conditions
7 
 * are met:
8 
 *
9 
 * - Redistributions of source code must retain the above copyright
10 
 *   notice, this list of conditions and the following disclaimer.
11 
 * - Redistributions in binary form must reproduce the above copyright
12 
 *   notice, this list of conditions and the following disclaimer in the
13 
 *   documentation and/or other materials provided with the distribution.
14 
 * - The name of the author may not be used to endorse or promote products
15 
 *   derived from this software without specific prior written permission.
16 
 *
17 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 
 */
1702 cejka 28 
 
1822 jermar 29 
/** @addtogroup generic
1702 cejka 30 
 * @{
31 
 */
1288 jermar 32 
 
33 
/**
1702 cejka 34 
 * @file
1288 jermar 35 
 * @brief   Copying between kernel and userspace.
36 
 *
37 
 * This file contains sanitized functions for copying data
38 
 * between kernel and userspace.
39 
 */
40 
 
41 
#include <syscall/copy.h>
42 
#include <proc/thread.h>
43 
#include <mm/as.h>
44 
#include <macros.h>
45 
#include <arch.h>
46 
#include <errno.h>
47 
 
48 
/** Copy data from userspace to kernel.
49 
 *
50 
 * Provisions are made to return value even after page fault.
51 
 *
52 
 * This function can be called only from syscall.
53 
 *
54 
 * @param dst Destination kernel address.
55 
 * @param uspace_src Source userspace address.
56 
 * @param size Size of the data to be copied.
57 
 *
58 
 * @return 0 on success or error code from @ref errno.h.
59 
 */
1293 palkovsky 60 
int copy_from_uspace(void *dst, const void *uspace_src, size_t size)
1288 jermar 61 
{
62 
    ipl_t ipl;
63 
    int rc;
64 
 
65 
    ASSERT(THREAD);
66 
    ASSERT(!THREAD->in_copy_from_uspace);
67 
 
68 
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1780 jermar 69 
        if (overlaps((uintptr_t) uspace_src, size,
1288 jermar 70 
            KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) {
71 
            /*
72 
             * The userspace source block conflicts with kernel address space.
73 
             */
74 
            return EPERM;
75 
        }
76 
    }
77 
 
78 
    ipl = interrupts_disable();
79 
    THREAD->in_copy_from_uspace = true;
80 
 
81 
    rc = memcpy_from_uspace(dst, uspace_src, size);
82 
 
83 
    THREAD->in_copy_from_uspace = false;
84 
 
85 
    interrupts_restore(ipl);
86 
    return !rc ? EPERM : 0;
87 
}
88 
 
89 
/** Copy data from kernel to userspace.
90 
 *
91 
 * Provisions are made to return value even after page fault.
92 
 *
93 
 * This function can be called only from syscall.
94 
 *
95 
 * @param uspace_dst Destination userspace address.
1708 jermar 96 
 * @param src Source kernel address.
1288 jermar 97 
 * @param size Size of the data to be copied.
98 
 *
99 
 * @return 0 on success or error code from @ref errno.h.
100 
 */
1293 palkovsky 101 
int copy_to_uspace(void *uspace_dst, const void *src, size_t size)
1288 jermar 102 
{
103 
    ipl_t ipl;
104 
    int rc;
105 
 
106 
    ASSERT(THREAD);
1888 jermar 107 
    ASSERT(!THREAD->in_copy_to_uspace);
1288 jermar 108 
 
109 
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
1780 jermar 110 
        if (overlaps((uintptr_t) uspace_dst, size,
1288 jermar 111 
            KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) {
112 
            /*
113 
             * The userspace destination block conflicts with kernel address space.
114 
             */
115 
            return EPERM;
116 
        }
117 
    }
118 
 
119 
    ipl = interrupts_disable();
1888 jermar 120 
    THREAD->in_copy_to_uspace = true;
1288 jermar 121 
 
122 
    rc = memcpy_to_uspace(uspace_dst, src, size);
123 
 
1888 jermar 124 
    THREAD->in_copy_to_uspace = false;
1288 jermar 125 
 
126 
    interrupts_restore(ipl);
127 
    return !rc ? EPERM : 0;
128 
}
1702 cejka 129 
 
1822 jermar 130 
/** @}
1702 cejka 131 
 */