diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/drm/drm_auth.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/char/drm/drm_auth.c')
-rw-r--r-- | drivers/char/drm/drm_auth.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/drivers/char/drm/drm_auth.c b/drivers/char/drm/drm_auth.c new file mode 100644 index 000000000000..b428761c4e91 --- /dev/null +++ b/drivers/char/drm/drm_auth.c | |||
@@ -0,0 +1,230 @@ | |||
1 | /** | ||
2 | * \file drm_auth.h | ||
3 | * IOCTLs for authentication | ||
4 | * | ||
5 | * \author Rickard E. (Rik) Faith <faith@valinux.com> | ||
6 | * \author Gareth Hughes <gareth@valinux.com> | ||
7 | */ | ||
8 | |||
9 | /* | ||
10 | * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com | ||
11 | * | ||
12 | * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. | ||
13 | * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. | ||
14 | * All Rights Reserved. | ||
15 | * | ||
16 | * Permission is hereby granted, free of charge, to any person obtaining a | ||
17 | * copy of this software and associated documentation files (the "Software"), | ||
18 | * to deal in the Software without restriction, including without limitation | ||
19 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | ||
20 | * and/or sell copies of the Software, and to permit persons to whom the | ||
21 | * Software is furnished to do so, subject to the following conditions: | ||
22 | * | ||
23 | * The above copyright notice and this permission notice (including the next | ||
24 | * paragraph) shall be included in all copies or substantial portions of the | ||
25 | * Software. | ||
26 | * | ||
27 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||
28 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||
29 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | ||
30 | * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR | ||
31 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, | ||
32 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR | ||
33 | * OTHER DEALINGS IN THE SOFTWARE. | ||
34 | */ | ||
35 | |||
36 | #include "drmP.h" | ||
37 | |||
38 | /** | ||
39 | * Generate a hash key from a magic. | ||
40 | * | ||
41 | * \param magic magic. | ||
42 | * \return hash key. | ||
43 | * | ||
44 | * The key is the modulus of the hash table size, #DRM_HASH_SIZE, which must be | ||
45 | * a power of 2. | ||
46 | */ | ||
47 | static int drm_hash_magic(drm_magic_t magic) | ||
48 | { | ||
49 | return magic & (DRM_HASH_SIZE-1); | ||
50 | } | ||
51 | |||
52 | /** | ||
53 | * Find the file with the given magic number. | ||
54 | * | ||
55 | * \param dev DRM device. | ||
56 | * \param magic magic number. | ||
57 | * | ||
58 | * Searches in drm_device::magiclist within all files with the same hash key | ||
59 | * the one with matching magic number, while holding the drm_device::struct_sem | ||
60 | * lock. | ||
61 | */ | ||
62 | static drm_file_t *drm_find_file(drm_device_t *dev, drm_magic_t magic) | ||
63 | { | ||
64 | drm_file_t *retval = NULL; | ||
65 | drm_magic_entry_t *pt; | ||
66 | int hash = drm_hash_magic(magic); | ||
67 | |||
68 | down(&dev->struct_sem); | ||
69 | for (pt = dev->magiclist[hash].head; pt; pt = pt->next) { | ||
70 | if (pt->magic == magic) { | ||
71 | retval = pt->priv; | ||
72 | break; | ||
73 | } | ||
74 | } | ||
75 | up(&dev->struct_sem); | ||
76 | return retval; | ||
77 | } | ||
78 | |||
79 | /** | ||
80 | * Adds a magic number. | ||
81 | * | ||
82 | * \param dev DRM device. | ||
83 | * \param priv file private data. | ||
84 | * \param magic magic number. | ||
85 | * | ||
86 | * Creates a drm_magic_entry structure and appends to the linked list | ||
87 | * associated the magic number hash key in drm_device::magiclist, while holding | ||
88 | * the drm_device::struct_sem lock. | ||
89 | */ | ||
90 | int drm_add_magic(drm_device_t *dev, drm_file_t *priv, drm_magic_t magic) | ||
91 | { | ||
92 | int hash; | ||
93 | drm_magic_entry_t *entry; | ||
94 | |||
95 | DRM_DEBUG("%d\n", magic); | ||
96 | |||
97 | hash = drm_hash_magic(magic); | ||
98 | entry = drm_alloc(sizeof(*entry), DRM_MEM_MAGIC); | ||
99 | if (!entry) return -ENOMEM; | ||
100 | memset(entry, 0, sizeof(*entry)); | ||
101 | entry->magic = magic; | ||
102 | entry->priv = priv; | ||
103 | entry->next = NULL; | ||
104 | |||
105 | down(&dev->struct_sem); | ||
106 | if (dev->magiclist[hash].tail) { | ||
107 | dev->magiclist[hash].tail->next = entry; | ||
108 | dev->magiclist[hash].tail = entry; | ||
109 | } else { | ||
110 | dev->magiclist[hash].head = entry; | ||
111 | dev->magiclist[hash].tail = entry; | ||
112 | } | ||
113 | up(&dev->struct_sem); | ||
114 | |||
115 | return 0; | ||
116 | } | ||
117 | |||
118 | /** | ||
119 | * Remove a magic number. | ||
120 | * | ||
121 | * \param dev DRM device. | ||
122 | * \param magic magic number. | ||
123 | * | ||
124 | * Searches and unlinks the entry in drm_device::magiclist with the magic | ||
125 | * number hash key, while holding the drm_device::struct_sem lock. | ||
126 | */ | ||
127 | int drm_remove_magic(drm_device_t *dev, drm_magic_t magic) | ||
128 | { | ||
129 | drm_magic_entry_t *prev = NULL; | ||
130 | drm_magic_entry_t *pt; | ||
131 | int hash; | ||
132 | |||
133 | |||
134 | DRM_DEBUG("%d\n", magic); | ||
135 | hash = drm_hash_magic(magic); | ||
136 | |||
137 | down(&dev->struct_sem); | ||
138 | for (pt = dev->magiclist[hash].head; pt; prev = pt, pt = pt->next) { | ||
139 | if (pt->magic == magic) { | ||
140 | if (dev->magiclist[hash].head == pt) { | ||
141 | dev->magiclist[hash].head = pt->next; | ||
142 | } | ||
143 | if (dev->magiclist[hash].tail == pt) { | ||
144 | dev->magiclist[hash].tail = prev; | ||
145 | } | ||
146 | if (prev) { | ||
147 | prev->next = pt->next; | ||
148 | } | ||
149 | up(&dev->struct_sem); | ||
150 | return 0; | ||
151 | } | ||
152 | } | ||
153 | up(&dev->struct_sem); | ||
154 | |||
155 | drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC); | ||
156 | |||
157 | return -EINVAL; | ||
158 | } | ||
159 | |||
160 | /** | ||
161 | * Get a unique magic number (ioctl). | ||
162 | * | ||
163 | * \param inode device inode. | ||
164 | * \param filp file pointer. | ||
165 | * \param cmd command. | ||
166 | * \param arg pointer to a resulting drm_auth structure. | ||
167 | * \return zero on success, or a negative number on failure. | ||
168 | * | ||
169 | * If there is a magic number in drm_file::magic then use it, otherwise | ||
170 | * searches an unique non-zero magic number and add it associating it with \p | ||
171 | * filp. | ||
172 | */ | ||
173 | int drm_getmagic(struct inode *inode, struct file *filp, | ||
174 | unsigned int cmd, unsigned long arg) | ||
175 | { | ||
176 | static drm_magic_t sequence = 0; | ||
177 | static DEFINE_SPINLOCK(lock); | ||
178 | drm_file_t *priv = filp->private_data; | ||
179 | drm_device_t *dev = priv->head->dev; | ||
180 | drm_auth_t auth; | ||
181 | |||
182 | /* Find unique magic */ | ||
183 | if (priv->magic) { | ||
184 | auth.magic = priv->magic; | ||
185 | } else { | ||
186 | do { | ||
187 | spin_lock(&lock); | ||
188 | if (!sequence) ++sequence; /* reserve 0 */ | ||
189 | auth.magic = sequence++; | ||
190 | spin_unlock(&lock); | ||
191 | } while (drm_find_file(dev, auth.magic)); | ||
192 | priv->magic = auth.magic; | ||
193 | drm_add_magic(dev, priv, auth.magic); | ||
194 | } | ||
195 | |||
196 | DRM_DEBUG("%u\n", auth.magic); | ||
197 | if (copy_to_user((drm_auth_t __user *)arg, &auth, sizeof(auth))) | ||
198 | return -EFAULT; | ||
199 | return 0; | ||
200 | } | ||
201 | |||
202 | /** | ||
203 | * Authenticate with a magic. | ||
204 | * | ||
205 | * \param inode device inode. | ||
206 | * \param filp file pointer. | ||
207 | * \param cmd command. | ||
208 | * \param arg pointer to a drm_auth structure. | ||
209 | * \return zero if authentication successed, or a negative number otherwise. | ||
210 | * | ||
211 | * Checks if \p filp is associated with the magic number passed in \arg. | ||
212 | */ | ||
213 | int drm_authmagic(struct inode *inode, struct file *filp, | ||
214 | unsigned int cmd, unsigned long arg) | ||
215 | { | ||
216 | drm_file_t *priv = filp->private_data; | ||
217 | drm_device_t *dev = priv->head->dev; | ||
218 | drm_auth_t auth; | ||
219 | drm_file_t *file; | ||
220 | |||
221 | if (copy_from_user(&auth, (drm_auth_t __user *)arg, sizeof(auth))) | ||
222 | return -EFAULT; | ||
223 | DRM_DEBUG("%u\n", auth.magic); | ||
224 | if ((file = drm_find_file(dev, auth.magic))) { | ||
225 | file->authenticated = 1; | ||
226 | drm_remove_magic(dev, auth.magic); | ||
227 | return 0; | ||
228 | } | ||
229 | return -EINVAL; | ||
230 | } | ||