]>
Commit | Line | Data |
---|---|---|
04277e02 | 1 | /* Copyright (C) 1994-2019 Free Software Foundation, Inc. |
478b92f0 | 2 | This file is part of the GNU C Library. |
28f540f4 | 3 | |
478b92f0 | 4 | The GNU C Library is free software; you can redistribute it and/or |
41bdb6e2 AJ |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either | |
7 | version 2.1 of the License, or (at your option) any later version. | |
28f540f4 | 8 | |
478b92f0 UD |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
41bdb6e2 | 12 | Lesser General Public License for more details. |
28f540f4 | 13 | |
41bdb6e2 | 14 | You should have received a copy of the GNU Lesser General Public |
59ba27a6 PE |
15 | License along with the GNU C Library; if not, see |
16 | <http://www.gnu.org/licenses/>. */ | |
28f540f4 RM |
17 | |
18 | #include <sys/types.h> | |
19 | #include <sys/mman.h> | |
20 | #include <errno.h> | |
21 | #include <hurd.h> | |
22 | #include <hurd/fd.h> | |
23 | ||
24 | /* Map addresses starting near ADDR and extending for LEN bytes. from | |
25 | OFFSET into the file FD describes according to PROT and FLAGS. If ADDR | |
26 | is nonzero, it is the desired mapping address. If the MAP_FIXED bit is | |
27 | set in FLAGS, the mapping will be at ADDR exactly (which must be | |
28 | page-aligned); otherwise the system chooses a convenient nearby address. | |
f17a4233 | 29 | The return value is the actual mapping address chosen or (void *) -1 |
28f540f4 RM |
30 | for errors (in which case `errno' is set). A successful `mmap' call |
31 | deallocates any previous mapping for the affected region. */ | |
32 | ||
f17a4233 JM |
33 | void * |
34 | __mmap (void *addr, size_t len, int prot, int flags, int fd, off_t offset) | |
28f540f4 RM |
35 | { |
36 | error_t err; | |
37 | vm_prot_t vmprot; | |
38 | memory_object_t memobj; | |
39 | vm_address_t mapaddr; | |
65bf5fa3 | 40 | |
57a491d1 RM |
41 | mapaddr = (vm_address_t) addr; |
42 | ||
fbf86dda | 43 | /* ADDR and OFFSET must be page-aligned. */ |
51a3985d | 44 | if ((mapaddr & (__vm_page_size - 1)) || (offset & (__vm_page_size - 1))) |
f17a4233 | 45 | return (void *) (long int) __hurd_fail (EINVAL); |
fbf86dda | 46 | |
57a491d1 RM |
47 | if ((flags & (MAP_TYPE|MAP_INHERIT)) == MAP_ANON |
48 | && prot == (PROT_READ|PROT_WRITE)) /* cf VM_PROT_DEFAULT */ | |
49 | { | |
50 | /* vm_allocate has (a little) less overhead in the kernel too. */ | |
868df0f9 | 51 | err = __vm_allocate (__mach_task_self (), &mapaddr, len, mapaddr == 0); |
57a491d1 | 52 | |
0ea698ae | 53 | if (err == KERN_NO_SPACE) |
57a491d1 | 54 | { |
0ea698ae ST |
55 | if (flags & MAP_FIXED) |
56 | { | |
57 | /* XXX this is not atomic as it is in unix! */ | |
58 | /* The region is already allocated; deallocate it first. */ | |
59 | err = __vm_deallocate (__mach_task_self (), mapaddr, len); | |
60 | if (!err) | |
61 | err = __vm_allocate (__mach_task_self (), &mapaddr, len, 0); | |
62 | } | |
868df0f9 | 63 | else if (mapaddr != 0) |
0ea698ae | 64 | err = __vm_allocate (__mach_task_self (), &mapaddr, len, 1); |
57a491d1 RM |
65 | } |
66 | ||
f17a4233 | 67 | return err ? (void *) (long int) __hurd_fail (err) : (void *) mapaddr; |
57a491d1 RM |
68 | } |
69 | ||
28f540f4 RM |
70 | vmprot = VM_PROT_NONE; |
71 | if (prot & PROT_READ) | |
72 | vmprot |= VM_PROT_READ; | |
73 | if (prot & PROT_WRITE) | |
74 | vmprot |= VM_PROT_WRITE; | |
75 | if (prot & PROT_EXEC) | |
76 | vmprot |= VM_PROT_EXECUTE; | |
77 | ||
78 | switch (flags & MAP_TYPE) | |
79 | { | |
80 | default: | |
f17a4233 | 81 | return (void *) (long int) __hurd_fail (EINVAL); |
28f540f4 RM |
82 | |
83 | case MAP_ANON: | |
84 | memobj = MACH_PORT_NULL; | |
85 | break; | |
86 | ||
87 | case MAP_FILE: | |
7752137a | 88 | case 0: /* Allow, e.g., just MAP_SHARED. */ |
28f540f4 RM |
89 | { |
90 | mach_port_t robj, wobj; | |
91 | if (err = HURD_DPORT_USE (fd, __io_map (port, &robj, &wobj))) | |
edc7ae46 RM |
92 | { |
93 | if (err == MIG_BAD_ID || err == EOPNOTSUPP || err == ENOSYS) | |
94 | err = ENODEV; /* File descriptor doesn't support mmap. */ | |
f17a4233 | 95 | return (void *) (long int) __hurd_dfail (fd, err); |
edc7ae46 | 96 | } |
28f540f4 RM |
97 | switch (prot & (PROT_READ|PROT_WRITE)) |
98 | { | |
e86c5b64 ST |
99 | /* Although it apparently doesn't make sense to map a file with |
100 | protection set to PROT_NONE, it is actually sometimes done. | |
101 | In particular, that's how localedef reserves some space for | |
102 | the locale archive file, the rationale being that some | |
103 | implementations take into account whether the mapping is | |
104 | anonymous or not when selecting addresses. */ | |
105 | case PROT_NONE: | |
28f540f4 RM |
106 | case PROT_READ: |
107 | memobj = robj; | |
1a3a58fd RM |
108 | if (wobj != MACH_PORT_NULL) |
109 | __mach_port_deallocate (__mach_task_self (), wobj); | |
28f540f4 RM |
110 | break; |
111 | case PROT_WRITE: | |
112 | memobj = wobj; | |
1a3a58fd RM |
113 | if (robj != MACH_PORT_NULL) |
114 | __mach_port_deallocate (__mach_task_self (), robj); | |
28f540f4 RM |
115 | break; |
116 | case PROT_READ|PROT_WRITE: | |
28f540f4 | 117 | if (robj == wobj) |
1a3a58fd RM |
118 | { |
119 | memobj = wobj; | |
120 | /* Remove extra reference. */ | |
121 | __mach_port_deallocate (__mach_task_self (), memobj); | |
122 | } | |
123 | else if (wobj == MACH_PORT_NULL && /* Not writable by mapping. */ | |
907a1bac | 124 | !(flags & MAP_SHARED)) |
1a3a58fd RM |
125 | /* The file can only be mapped for reading. Since we are |
126 | making a private mapping, we will never try to write the | |
127 | object anyway, so we don't care. */ | |
128 | memobj = robj; | |
28f540f4 RM |
129 | else |
130 | { | |
131 | __mach_port_deallocate (__mach_task_self (), wobj); | |
f17a4233 | 132 | return (void *) (long int) __hurd_fail (EACCES); |
28f540f4 RM |
133 | } |
134 | break; | |
e86c5b64 ST |
135 | default: |
136 | __builtin_unreachable (); | |
28f540f4 RM |
137 | } |
138 | break; | |
139 | /* XXX handle MAP_NOEXTEND */ | |
140 | } | |
141 | } | |
142 | ||
65bf5fa3 RM |
143 | /* XXX handle MAP_INHERIT */ |
144 | ||
28f540f4 RM |
145 | err = __vm_map (__mach_task_self (), |
146 | &mapaddr, (vm_size_t) len, (vm_address_t) 0, | |
868df0f9 | 147 | mapaddr == 0, |
28f540f4 | 148 | memobj, (vm_offset_t) offset, |
65bf5fa3 | 149 | ! (flags & MAP_SHARED), |
28f540f4 | 150 | vmprot, VM_PROT_ALL, |
65bf5fa3 RM |
151 | (flags & MAP_SHARED) ? VM_INHERIT_SHARE : VM_INHERIT_COPY); |
152 | ||
0ea698ae | 153 | if (err == KERN_NO_SPACE) |
787e4db9 | 154 | { |
0ea698ae ST |
155 | if (flags & MAP_FIXED) |
156 | { | |
157 | /* XXX this is not atomic as it is in unix! */ | |
158 | /* The region is already allocated; deallocate it first. */ | |
159 | err = __vm_deallocate (__mach_task_self (), mapaddr, len); | |
160 | if (! err) | |
161 | err = __vm_map (__mach_task_self (), | |
162 | &mapaddr, (vm_size_t) len, (vm_address_t) 0, | |
163 | 0, memobj, (vm_offset_t) offset, | |
164 | ! (flags & MAP_SHARED), | |
165 | vmprot, VM_PROT_ALL, | |
166 | (flags & MAP_SHARED) ? VM_INHERIT_SHARE | |
167 | : VM_INHERIT_COPY); | |
168 | } | |
868df0f9 | 169 | else if (mapaddr != 0) |
787e4db9 RM |
170 | err = __vm_map (__mach_task_self (), |
171 | &mapaddr, (vm_size_t) len, (vm_address_t) 0, | |
0ea698ae | 172 | 1, memobj, (vm_offset_t) offset, |
f36f8dcf | 173 | ! (flags & MAP_SHARED), |
787e4db9 | 174 | vmprot, VM_PROT_ALL, |
f36f8dcf RM |
175 | (flags & MAP_SHARED) ? VM_INHERIT_SHARE |
176 | : VM_INHERIT_COPY); | |
787e4db9 | 177 | } |
28f540f4 RM |
178 | |
179 | if (memobj != MACH_PORT_NULL) | |
180 | __mach_port_deallocate (__mach_task_self (), memobj); | |
181 | ||
65bf5fa3 | 182 | if (err) |
f17a4233 | 183 | return (void *) (long int) __hurd_fail (err); |
65bf5fa3 | 184 | |
f17a4233 | 185 | return (void *) mapaddr; |
28f540f4 | 186 | } |
6408bdde | 187 | |
a166531f | 188 | libc_hidden_def (__mmap) |
6408bdde | 189 | weak_alias (__mmap, mmap) |