1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/*
* Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Hyra nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/mount.h>
#include <sys/vfs.h>
#include <sys/errno.h>
#include <vm/dynalloc.h>
#include <assert.h>
#include <string.h>
/* TODO: Make this more flexible */
#define MOUNTLIST_SIZE 8
/* Mountlist entry */
struct mountlist_entry {
TAILQ_HEAD(, mount) buckets;
};
static struct mountlist_entry *mountlist = NULL;
static int
vfs_create_mp(const char *path, int mntflags, struct mount **mp_out)
{
struct mount *mp;
mp = dynalloc(sizeof(struct mount));
if (mp == NULL) {
return -ENOMEM;
}
mp->flags = mntflags;
*mp_out = mp;
return 0;
}
static int
mount(const char *source, const char *target, const char *filesystemtype,
unsigned long mountflags, const void *data)
{
struct vnode *source_vnode;
struct fs_info *info;
int status;
if (source == NULL || target == NULL || filesystemtype == NULL)
return -EFAULT;
/*
* Check mount flags.
*
* XXX: No flags implemented yet.
*/
if (mountflags != 0)
return -EINVAL;
/* Locate source, if any */
if (strcmp(source, "none") == 0) {
source_vnode = NULL;
} else {
status = vfs_path_to_node(source, &source_vnode);
if (status != 0)
return status;
}
/* Locate filesystem */
info = vfs_byname(filesystemtype);
if (info == NULL)
return -ENODEV;
/* Create mount point */
status = vfs_mount(target, 0, info);
if (status != 0)
return status;
/* Initialize filesystem if needed */
if (info->vfsops->init != NULL)
return info->vfsops->init(info, source_vnode);
return 0;
}
/*
* Mount a mountpoint
*
* @path: Path this mountpoint belongs to
* @mntflags: Flags to mount with
* @fs: Filesystem to mount
*
* If this mount entry already exists, -EEXIST
* will be returned.
*/
int
vfs_mount(const char *path, int mntflags, struct fs_info *fs)
{
size_t hash;
int status;
struct mountlist_entry *entry;
struct mount *mp;
/* Exclude leading slash */
if (*path == '/') {
++path;
}
hash = vfs_hash_path(path);
if ((status = vfs_create_mp(path, mntflags, &mp)) != 0) {
return status;
}
if (hash == -1) {
/* Something is wrong with the path */
return -EINVAL;
}
if (vfs_get_mp(path, NULL) == 0) {
/* mount hit, do not duplicate this entry */
return -EEXIST;
}
if ((status = vfs_alloc_vnode(&fs->vnode, mp, VDIR)) != 0) {
return status;
}
mp->phash = hash;
mp->fs = fs;
fs->vnode->vops = fs->vops;
entry = &mountlist[hash % MOUNTLIST_SIZE];
TAILQ_INSERT_TAIL(&entry->buckets, mp, link);
return 0;
}
/*
* Fetch mountpoint
*
* @path: Path of target mountpoint
* @mp: Pointer of variable where mountpoint fetched will
* be stored
*
* Returns 0 upon a mplist hit, on a mplist miss this
* function returns -ENOENT.
*/
int
vfs_get_mp(const char *path, struct mount **mp)
{
size_t hash;
struct mountlist_entry *entry;
struct mount *mount_iter;
/* Exclude leading slash */
if (*path == '/') {
++path;
}
hash = vfs_hash_path(path);
if (hash == 0) {
/* Something is wrong with the path */
return -EINVAL;
}
entry = &mountlist[hash % MOUNTLIST_SIZE];
TAILQ_FOREACH(mount_iter, &entry->buckets, link) {
if (mount_iter->phash == hash) {
if (mp != NULL) *mp = mount_iter;
return 0;
}
}
return -ENOENT;
}
void
vfs_mount_init(void)
{
mountlist = dynalloc(sizeof(struct mountlist_entry) * MOUNTLIST_SIZE);
__assert(mountlist != NULL);
for (size_t i = 0; i < MOUNTLIST_SIZE; ++i) {
TAILQ_INIT(&mountlist[i].buckets);
}
}
uint64_t
sys_mount(struct syscall_args *args)
{
return mount((void *)args->arg0, (void *)args->arg1, (void *)args->arg2,
(unsigned long)args->arg3, (void *)args->arg4);
}
|
