diff options
Diffstat (limited to 'drivers/char/raw.c')
-rw-r--r-- | drivers/char/raw.c | 273 |
1 files changed, 160 insertions, 113 deletions
diff --git a/drivers/char/raw.c b/drivers/char/raw.c index 64acd05f71c8..bfe25ea9766b 100644 --- a/drivers/char/raw.c +++ b/drivers/char/raw.c | |||
@@ -19,7 +19,8 @@ | |||
19 | #include <linux/cdev.h> | 19 | #include <linux/cdev.h> |
20 | #include <linux/device.h> | 20 | #include <linux/device.h> |
21 | #include <linux/mutex.h> | 21 | #include <linux/mutex.h> |
22 | #include <linux/smp_lock.h> | 22 | #include <linux/gfp.h> |
23 | #include <linux/compat.h> | ||
23 | 24 | ||
24 | #include <asm/uaccess.h> | 25 | #include <asm/uaccess.h> |
25 | 26 | ||
@@ -54,7 +55,6 @@ static int raw_open(struct inode *inode, struct file *filp) | |||
54 | return 0; | 55 | return 0; |
55 | } | 56 | } |
56 | 57 | ||
57 | lock_kernel(); | ||
58 | mutex_lock(&raw_mutex); | 58 | mutex_lock(&raw_mutex); |
59 | 59 | ||
60 | /* | 60 | /* |
@@ -81,7 +81,6 @@ static int raw_open(struct inode *inode, struct file *filp) | |||
81 | bdev->bd_inode->i_mapping; | 81 | bdev->bd_inode->i_mapping; |
82 | filp->private_data = bdev; | 82 | filp->private_data = bdev; |
83 | mutex_unlock(&raw_mutex); | 83 | mutex_unlock(&raw_mutex); |
84 | unlock_kernel(); | ||
85 | return 0; | 84 | return 0; |
86 | 85 | ||
87 | out2: | 86 | out2: |
@@ -90,7 +89,6 @@ out1: | |||
90 | blkdev_put(bdev, filp->f_mode); | 89 | blkdev_put(bdev, filp->f_mode); |
91 | out: | 90 | out: |
92 | mutex_unlock(&raw_mutex); | 91 | mutex_unlock(&raw_mutex); |
93 | unlock_kernel(); | ||
94 | return err; | 92 | return err; |
95 | } | 93 | } |
96 | 94 | ||
@@ -120,143 +118,192 @@ static int raw_release(struct inode *inode, struct file *filp) | |||
120 | /* | 118 | /* |
121 | * Forward ioctls to the underlying block device. | 119 | * Forward ioctls to the underlying block device. |
122 | */ | 120 | */ |
123 | static int | 121 | static long |
124 | raw_ioctl(struct inode *inode, struct file *filp, | 122 | raw_ioctl(struct file *filp, unsigned int command, unsigned long arg) |
125 | unsigned int command, unsigned long arg) | ||
126 | { | 123 | { |
127 | struct block_device *bdev = filp->private_data; | 124 | struct block_device *bdev = filp->private_data; |
128 | |||
129 | return blkdev_ioctl(bdev, 0, command, arg); | 125 | return blkdev_ioctl(bdev, 0, command, arg); |
130 | } | 126 | } |
131 | 127 | ||
132 | static void bind_device(struct raw_config_request *rq) | 128 | static int bind_set(int number, u64 major, u64 minor) |
133 | { | 129 | { |
134 | device_destroy(raw_class, MKDEV(RAW_MAJOR, rq->raw_minor)); | 130 | dev_t dev = MKDEV(major, minor); |
135 | device_create(raw_class, NULL, MKDEV(RAW_MAJOR, rq->raw_minor), NULL, | 131 | struct raw_device_data *rawdev; |
136 | "raw%d", rq->raw_minor); | 132 | int err = 0; |
133 | |||
134 | if (number <= 0 || number >= MAX_RAW_MINORS) | ||
135 | return -EINVAL; | ||
136 | |||
137 | if (MAJOR(dev) != major || MINOR(dev) != minor) | ||
138 | return -EINVAL; | ||
139 | |||
140 | rawdev = &raw_devices[number]; | ||
141 | |||
142 | /* | ||
143 | * This is like making block devices, so demand the | ||
144 | * same capability | ||
145 | */ | ||
146 | if (!capable(CAP_SYS_ADMIN)) | ||
147 | return -EPERM; | ||
148 | |||
149 | /* | ||
150 | * For now, we don't need to check that the underlying | ||
151 | * block device is present or not: we can do that when | ||
152 | * the raw device is opened. Just check that the | ||
153 | * major/minor numbers make sense. | ||
154 | */ | ||
155 | |||
156 | if (MAJOR(dev) == 0 && dev != 0) | ||
157 | return -EINVAL; | ||
158 | |||
159 | mutex_lock(&raw_mutex); | ||
160 | if (rawdev->inuse) { | ||
161 | mutex_unlock(&raw_mutex); | ||
162 | return -EBUSY; | ||
163 | } | ||
164 | if (rawdev->binding) { | ||
165 | bdput(rawdev->binding); | ||
166 | module_put(THIS_MODULE); | ||
167 | } | ||
168 | if (!dev) { | ||
169 | /* unbind */ | ||
170 | rawdev->binding = NULL; | ||
171 | device_destroy(raw_class, MKDEV(RAW_MAJOR, number)); | ||
172 | } else { | ||
173 | rawdev->binding = bdget(dev); | ||
174 | if (rawdev->binding == NULL) { | ||
175 | err = -ENOMEM; | ||
176 | } else { | ||
177 | dev_t raw = MKDEV(RAW_MAJOR, number); | ||
178 | __module_get(THIS_MODULE); | ||
179 | device_destroy(raw_class, raw); | ||
180 | device_create(raw_class, NULL, raw, NULL, | ||
181 | "raw%d", number); | ||
182 | } | ||
183 | } | ||
184 | mutex_unlock(&raw_mutex); | ||
185 | return err; | ||
186 | } | ||
187 | |||
188 | static int bind_get(int number, dev_t *dev) | ||
189 | { | ||
190 | struct raw_device_data *rawdev; | ||
191 | struct block_device *bdev; | ||
192 | |||
193 | if (number <= 0 || number >= MAX_RAW_MINORS) | ||
194 | return -EINVAL; | ||
195 | |||
196 | rawdev = &raw_devices[number]; | ||
197 | |||
198 | mutex_lock(&raw_mutex); | ||
199 | bdev = rawdev->binding; | ||
200 | *dev = bdev ? bdev->bd_dev : 0; | ||
201 | mutex_unlock(&raw_mutex); | ||
202 | return 0; | ||
137 | } | 203 | } |
138 | 204 | ||
139 | /* | 205 | /* |
140 | * Deal with ioctls against the raw-device control interface, to bind | 206 | * Deal with ioctls against the raw-device control interface, to bind |
141 | * and unbind other raw devices. | 207 | * and unbind other raw devices. |
142 | */ | 208 | */ |
143 | static int raw_ctl_ioctl(struct inode *inode, struct file *filp, | 209 | static long raw_ctl_ioctl(struct file *filp, unsigned int command, |
144 | unsigned int command, unsigned long arg) | 210 | unsigned long arg) |
145 | { | 211 | { |
146 | struct raw_config_request rq; | 212 | struct raw_config_request rq; |
147 | struct raw_device_data *rawdev; | 213 | dev_t dev; |
148 | int err = 0; | 214 | int err; |
149 | 215 | ||
150 | switch (command) { | 216 | switch (command) { |
151 | case RAW_SETBIND: | 217 | case RAW_SETBIND: |
218 | if (copy_from_user(&rq, (void __user *) arg, sizeof(rq))) | ||
219 | return -EFAULT; | ||
220 | |||
221 | return bind_set(rq.raw_minor, rq.block_major, rq.block_minor); | ||
222 | |||
152 | case RAW_GETBIND: | 223 | case RAW_GETBIND: |
224 | if (copy_from_user(&rq, (void __user *) arg, sizeof(rq))) | ||
225 | return -EFAULT; | ||
153 | 226 | ||
154 | /* First, find out which raw minor we want */ | 227 | err = bind_get(rq.raw_minor, &dev); |
228 | if (err) | ||
229 | return err; | ||
155 | 230 | ||
156 | if (copy_from_user(&rq, (void __user *) arg, sizeof(rq))) { | 231 | rq.block_major = MAJOR(dev); |
157 | err = -EFAULT; | 232 | rq.block_minor = MINOR(dev); |
158 | goto out; | ||
159 | } | ||
160 | 233 | ||
161 | if (rq.raw_minor <= 0 || rq.raw_minor >= MAX_RAW_MINORS) { | 234 | if (copy_to_user((void __user *)arg, &rq, sizeof(rq))) |
162 | err = -EINVAL; | 235 | return -EFAULT; |
163 | goto out; | 236 | |
164 | } | 237 | return 0; |
165 | rawdev = &raw_devices[rq.raw_minor]; | ||
166 | |||
167 | if (command == RAW_SETBIND) { | ||
168 | dev_t dev; | ||
169 | |||
170 | /* | ||
171 | * This is like making block devices, so demand the | ||
172 | * same capability | ||
173 | */ | ||
174 | if (!capable(CAP_SYS_ADMIN)) { | ||
175 | err = -EPERM; | ||
176 | goto out; | ||
177 | } | ||
178 | |||
179 | /* | ||
180 | * For now, we don't need to check that the underlying | ||
181 | * block device is present or not: we can do that when | ||
182 | * the raw device is opened. Just check that the | ||
183 | * major/minor numbers make sense. | ||
184 | */ | ||
185 | |||
186 | dev = MKDEV(rq.block_major, rq.block_minor); | ||
187 | if ((rq.block_major == 0 && rq.block_minor != 0) || | ||
188 | MAJOR(dev) != rq.block_major || | ||
189 | MINOR(dev) != rq.block_minor) { | ||
190 | err = -EINVAL; | ||
191 | goto out; | ||
192 | } | ||
193 | |||
194 | mutex_lock(&raw_mutex); | ||
195 | if (rawdev->inuse) { | ||
196 | mutex_unlock(&raw_mutex); | ||
197 | err = -EBUSY; | ||
198 | goto out; | ||
199 | } | ||
200 | if (rawdev->binding) { | ||
201 | bdput(rawdev->binding); | ||
202 | module_put(THIS_MODULE); | ||
203 | } | ||
204 | if (rq.block_major == 0 && rq.block_minor == 0) { | ||
205 | /* unbind */ | ||
206 | rawdev->binding = NULL; | ||
207 | device_destroy(raw_class, | ||
208 | MKDEV(RAW_MAJOR, rq.raw_minor)); | ||
209 | } else { | ||
210 | rawdev->binding = bdget(dev); | ||
211 | if (rawdev->binding == NULL) | ||
212 | err = -ENOMEM; | ||
213 | else { | ||
214 | __module_get(THIS_MODULE); | ||
215 | bind_device(&rq); | ||
216 | } | ||
217 | } | ||
218 | mutex_unlock(&raw_mutex); | ||
219 | } else { | ||
220 | struct block_device *bdev; | ||
221 | |||
222 | mutex_lock(&raw_mutex); | ||
223 | bdev = rawdev->binding; | ||
224 | if (bdev) { | ||
225 | rq.block_major = MAJOR(bdev->bd_dev); | ||
226 | rq.block_minor = MINOR(bdev->bd_dev); | ||
227 | } else { | ||
228 | rq.block_major = rq.block_minor = 0; | ||
229 | } | ||
230 | mutex_unlock(&raw_mutex); | ||
231 | if (copy_to_user((void __user *)arg, &rq, sizeof(rq))) { | ||
232 | err = -EFAULT; | ||
233 | goto out; | ||
234 | } | ||
235 | } | ||
236 | break; | ||
237 | default: | ||
238 | err = -EINVAL; | ||
239 | break; | ||
240 | } | 238 | } |
241 | out: | 239 | |
242 | return err; | 240 | return -EINVAL; |
241 | } | ||
242 | |||
243 | #ifdef CONFIG_COMPAT | ||
244 | struct raw32_config_request { | ||
245 | compat_int_t raw_minor; | ||
246 | compat_u64 block_major; | ||
247 | compat_u64 block_minor; | ||
248 | }; | ||
249 | |||
250 | static long raw_ctl_compat_ioctl(struct file *file, unsigned int cmd, | ||
251 | unsigned long arg) | ||
252 | { | ||
253 | struct raw32_config_request __user *user_req = compat_ptr(arg); | ||
254 | struct raw32_config_request rq; | ||
255 | dev_t dev; | ||
256 | int err = 0; | ||
257 | |||
258 | switch (cmd) { | ||
259 | case RAW_SETBIND: | ||
260 | if (copy_from_user(&rq, user_req, sizeof(rq))) | ||
261 | return -EFAULT; | ||
262 | |||
263 | return bind_set(rq.raw_minor, rq.block_major, rq.block_minor); | ||
264 | |||
265 | case RAW_GETBIND: | ||
266 | if (copy_from_user(&rq, user_req, sizeof(rq))) | ||
267 | return -EFAULT; | ||
268 | |||
269 | err = bind_get(rq.raw_minor, &dev); | ||
270 | if (err) | ||
271 | return err; | ||
272 | |||
273 | rq.block_major = MAJOR(dev); | ||
274 | rq.block_minor = MINOR(dev); | ||
275 | |||
276 | if (copy_to_user(user_req, &rq, sizeof(rq))) | ||
277 | return -EFAULT; | ||
278 | |||
279 | return 0; | ||
280 | } | ||
281 | |||
282 | return -EINVAL; | ||
243 | } | 283 | } |
284 | #endif | ||
244 | 285 | ||
245 | static const struct file_operations raw_fops = { | 286 | static const struct file_operations raw_fops = { |
246 | .read = do_sync_read, | 287 | .read = do_sync_read, |
247 | .aio_read = generic_file_aio_read, | 288 | .aio_read = generic_file_aio_read, |
248 | .write = do_sync_write, | 289 | .write = do_sync_write, |
249 | .aio_write = blkdev_aio_write, | 290 | .aio_write = blkdev_aio_write, |
250 | .open = raw_open, | 291 | .fsync = blkdev_fsync, |
251 | .release= raw_release, | 292 | .open = raw_open, |
252 | .ioctl = raw_ioctl, | 293 | .release = raw_release, |
253 | .owner = THIS_MODULE, | 294 | .unlocked_ioctl = raw_ioctl, |
295 | .llseek = default_llseek, | ||
296 | .owner = THIS_MODULE, | ||
254 | }; | 297 | }; |
255 | 298 | ||
256 | static const struct file_operations raw_ctl_fops = { | 299 | static const struct file_operations raw_ctl_fops = { |
257 | .ioctl = raw_ctl_ioctl, | 300 | .unlocked_ioctl = raw_ctl_ioctl, |
258 | .open = raw_open, | 301 | #ifdef CONFIG_COMPAT |
259 | .owner = THIS_MODULE, | 302 | .compat_ioctl = raw_ctl_compat_ioctl, |
303 | #endif | ||
304 | .open = raw_open, | ||
305 | .owner = THIS_MODULE, | ||
306 | .llseek = noop_llseek, | ||
260 | }; | 307 | }; |
261 | 308 | ||
262 | static struct cdev raw_cdev; | 309 | static struct cdev raw_cdev; |