Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'work.__copy_to_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more __copy_.._user elimination from Al Viro.
* 'work.__copy_to_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
drm_dp_aux_dev: switch to read_iter/write_iter
+46
-63
+46
-63
drivers/gpu/drm/drm_dp_aux_dev.c
+46
-63
drivers/gpu/drm/drm_dp_aux_dev.c
···
32
32
#include <linux/kernel.h>
33
33
#include <linux/module.h>
34
34
#include <linux/uaccess.h>
35
+
#include <linux/uio.h>
35
36
#include <drm/drm_dp_helper.h>
36
37
#include <drm/drm_crtc.h>
37
38
#include <drm/drmP.h>
···
141
140
return fixed_size_llseek(file, offset, whence, AUX_MAX_OFFSET);
142
141
}
143
142
144
-
static ssize_t auxdev_read(struct file *file, char __user *buf, size_t count,
145
-
loff_t *offset)
143
+
static ssize_t auxdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
146
144
{
147
-
size_t bytes_pending, num_bytes_processed = 0;
148
-
struct drm_dp_aux_dev *aux_dev = file->private_data;
145
+
struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data;
146
+
loff_t pos = iocb->ki_pos;
149
147
ssize_t res = 0;
150
148
151
149
if (!atomic_inc_not_zero(&aux_dev->usecount))
152
150
return -ENODEV;
153
151
154
-
bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - (*offset));
152
+
iov_iter_truncate(to, AUX_MAX_OFFSET - pos);
155
153
156
-
if (!access_ok(VERIFY_WRITE, buf, bytes_pending)) {
157
-
res = -EFAULT;
158
-
goto out;
159
-
}
160
-
161
-
while (bytes_pending > 0) {
162
-
uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES];
163
-
ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf));
154
+
while (iov_iter_count(to)) {
155
+
uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES];
156
+
ssize_t todo = min(iov_iter_count(to), sizeof(buf));
164
157
165
158
if (signal_pending(current)) {
166
-
res = num_bytes_processed ?
167
-
num_bytes_processed : -ERESTARTSYS;
168
-
goto out;
159
+
res = -ERESTARTSYS;
160
+
break;
169
161
}
170
162
171
-
res = drm_dp_dpcd_read(aux_dev->aux, *offset, localbuf, todo);
172
-
if (res <= 0) {
173
-
res = num_bytes_processed ? num_bytes_processed : res;
174
-
goto out;
163
+
res = drm_dp_dpcd_read(aux_dev->aux, pos, buf, todo);
164
+
if (res <= 0)
165
+
break;
166
+
167
+
if (copy_to_iter(buf, res, to) != res) {
168
+
res = -EFAULT;
169
+
break;
175
170
}
176
-
if (__copy_to_user(buf + num_bytes_processed, localbuf, res)) {
177
-
res = num_bytes_processed ?
178
-
num_bytes_processed : -EFAULT;
179
-
goto out;
180
-
}
181
-
bytes_pending -= res;
182
-
*offset += res;
183
-
num_bytes_processed += res;
184
-
res = num_bytes_processed;
171
+
172
+
pos += res;
185
173
}
186
174
187
-
out:
175
+
if (pos != iocb->ki_pos)
176
+
res = pos - iocb->ki_pos;
177
+
iocb->ki_pos = pos;
178
+
188
179
atomic_dec(&aux_dev->usecount);
189
180
wake_up_atomic_t(&aux_dev->usecount);
190
181
return res;
191
182
}
192
183
193
-
static ssize_t auxdev_write(struct file *file, const char __user *buf,
194
-
size_t count, loff_t *offset)
184
+
static ssize_t auxdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
195
185
{
196
-
size_t bytes_pending, num_bytes_processed = 0;
197
-
struct drm_dp_aux_dev *aux_dev = file->private_data;
186
+
struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data;
187
+
loff_t pos = iocb->ki_pos;
198
188
ssize_t res = 0;
199
189
200
190
if (!atomic_inc_not_zero(&aux_dev->usecount))
201
191
return -ENODEV;
202
192
203
-
bytes_pending = min((loff_t)count, AUX_MAX_OFFSET - *offset);
193
+
iov_iter_truncate(from, AUX_MAX_OFFSET - pos);
204
194
205
-
if (!access_ok(VERIFY_READ, buf, bytes_pending)) {
206
-
res = -EFAULT;
207
-
goto out;
208
-
}
209
-
210
-
while (bytes_pending > 0) {
211
-
uint8_t localbuf[DP_AUX_MAX_PAYLOAD_BYTES];
212
-
ssize_t todo = min_t(size_t, bytes_pending, sizeof(localbuf));
195
+
while (iov_iter_count(from)) {
196
+
uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES];
197
+
ssize_t todo = min(iov_iter_count(from), sizeof(buf));
213
198
214
199
if (signal_pending(current)) {
215
-
res = num_bytes_processed ?
216
-
num_bytes_processed : -ERESTARTSYS;
217
-
goto out;
200
+
res = -ERESTARTSYS;
201
+
break;
218
202
}
219
203
220
-
if (__copy_from_user(localbuf,
221
-
buf + num_bytes_processed, todo)) {
222
-
res = num_bytes_processed ?
223
-
num_bytes_processed : -EFAULT;
224
-
goto out;
204
+
if (!copy_from_iter_full(buf, todo, from)) {
205
+
res = -EFAULT;
206
+
break;
225
207
}
226
208
227
-
res = drm_dp_dpcd_write(aux_dev->aux, *offset, localbuf, todo);
228
-
if (res <= 0) {
229
-
res = num_bytes_processed ? num_bytes_processed : res;
230
-
goto out;
231
-
}
232
-
bytes_pending -= res;
233
-
*offset += res;
234
-
num_bytes_processed += res;
235
-
res = num_bytes_processed;
209
+
res = drm_dp_dpcd_write(aux_dev->aux, pos, buf, todo);
210
+
if (res <= 0)
211
+
break;
212
+
213
+
pos += res;
236
214
}
237
215
238
-
out:
216
+
if (pos != iocb->ki_pos)
217
+
res = pos - iocb->ki_pos;
218
+
iocb->ki_pos = pos;
219
+
239
220
atomic_dec(&aux_dev->usecount);
240
221
wake_up_atomic_t(&aux_dev->usecount);
241
222
return res;
···
234
251
static const struct file_operations auxdev_fops = {
235
252
.owner = THIS_MODULE,
236
253
.llseek = auxdev_llseek,
237
-
.read = auxdev_read,
238
-
.write = auxdev_write,
254
+
.read_iter = auxdev_read_iter,
255
+
.write_iter = auxdev_write_iter,
239
256
.open = auxdev_open,
240
257
.release = auxdev_release,
241
258
};