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8#include <linux/file.h>
9#include <linux/fs.h>
10#include <linux/uaccess.h>
11#include <linux/slab.h>
12#include <linux/sync_file.h>
13
14#include "sync_debug.h"
15
16#define CREATE_TRACE_POINTS
17#include "sync_trace.h"
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49struct sw_sync_create_fence_data {
50 __u32 value;
51 char name[32];
52 __s32 fence;
53};
54
55#define SW_SYNC_IOC_MAGIC 'W'
56
57#define SW_SYNC_IOC_CREATE_FENCE _IOWR(SW_SYNC_IOC_MAGIC, 0,\
58 struct sw_sync_create_fence_data)
59
60#define SW_SYNC_IOC_INC _IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
61
62static const struct dma_fence_ops timeline_fence_ops;
63
64static inline struct sync_pt *dma_fence_to_sync_pt(struct dma_fence *fence)
65{
66 if (fence->ops != &timeline_fence_ops)
67 return NULL;
68 return container_of(fence, struct sync_pt, base);
69}
70
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76
77
78static struct sync_timeline *sync_timeline_create(const char *name)
79{
80 struct sync_timeline *obj;
81
82 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
83 if (!obj)
84 return NULL;
85
86 kref_init(&obj->kref);
87 obj->context = dma_fence_context_alloc(1);
88 strlcpy(obj->name, name, sizeof(obj->name));
89
90 obj->pt_tree = RB_ROOT;
91 INIT_LIST_HEAD(&obj->pt_list);
92 spin_lock_init(&obj->lock);
93
94 sync_timeline_debug_add(obj);
95
96 return obj;
97}
98
99static void sync_timeline_free(struct kref *kref)
100{
101 struct sync_timeline *obj =
102 container_of(kref, struct sync_timeline, kref);
103
104 sync_timeline_debug_remove(obj);
105
106 kfree(obj);
107}
108
109static void sync_timeline_get(struct sync_timeline *obj)
110{
111 kref_get(&obj->kref);
112}
113
114static void sync_timeline_put(struct sync_timeline *obj)
115{
116 kref_put(&obj->kref, sync_timeline_free);
117}
118
119static const char *timeline_fence_get_driver_name(struct dma_fence *fence)
120{
121 return "sw_sync";
122}
123
124static const char *timeline_fence_get_timeline_name(struct dma_fence *fence)
125{
126 struct sync_timeline *parent = dma_fence_parent(fence);
127
128 return parent->name;
129}
130
131static void timeline_fence_release(struct dma_fence *fence)
132{
133 struct sync_pt *pt = dma_fence_to_sync_pt(fence);
134 struct sync_timeline *parent = dma_fence_parent(fence);
135
136 if (!list_empty(&pt->link)) {
137 unsigned long flags;
138
139 spin_lock_irqsave(fence->lock, flags);
140 if (!list_empty(&pt->link)) {
141 list_del(&pt->link);
142 rb_erase(&pt->node, &parent->pt_tree);
143 }
144 spin_unlock_irqrestore(fence->lock, flags);
145 }
146
147 sync_timeline_put(parent);
148 dma_fence_free(fence);
149}
150
151static bool timeline_fence_signaled(struct dma_fence *fence)
152{
153 struct sync_timeline *parent = dma_fence_parent(fence);
154
155 return !__dma_fence_is_later(fence->seqno, parent->value, fence->ops);
156}
157
158static bool timeline_fence_enable_signaling(struct dma_fence *fence)
159{
160 return true;
161}
162
163static void timeline_fence_value_str(struct dma_fence *fence,
164 char *str, int size)
165{
166 snprintf(str, size, "%lld", fence->seqno);
167}
168
169static void timeline_fence_timeline_value_str(struct dma_fence *fence,
170 char *str, int size)
171{
172 struct sync_timeline *parent = dma_fence_parent(fence);
173
174 snprintf(str, size, "%d", parent->value);
175}
176
177static const struct dma_fence_ops timeline_fence_ops = {
178 .get_driver_name = timeline_fence_get_driver_name,
179 .get_timeline_name = timeline_fence_get_timeline_name,
180 .enable_signaling = timeline_fence_enable_signaling,
181 .signaled = timeline_fence_signaled,
182 .release = timeline_fence_release,
183 .fence_value_str = timeline_fence_value_str,
184 .timeline_value_str = timeline_fence_timeline_value_str,
185};
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194
195static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
196{
197 struct sync_pt *pt, *next;
198
199 trace_sync_timeline(obj);
200
201 spin_lock_irq(&obj->lock);
202
203 obj->value += inc;
204
205 list_for_each_entry_safe(pt, next, &obj->pt_list, link) {
206 if (!timeline_fence_signaled(&pt->base))
207 break;
208
209 list_del_init(&pt->link);
210 rb_erase(&pt->node, &obj->pt_tree);
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220 dma_fence_signal_locked(&pt->base);
221 }
222
223 spin_unlock_irq(&obj->lock);
224}
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235
236static struct sync_pt *sync_pt_create(struct sync_timeline *obj,
237 unsigned int value)
238{
239 struct sync_pt *pt;
240
241 pt = kzalloc(sizeof(*pt), GFP_KERNEL);
242 if (!pt)
243 return NULL;
244
245 sync_timeline_get(obj);
246 dma_fence_init(&pt->base, &timeline_fence_ops, &obj->lock,
247 obj->context, value);
248 INIT_LIST_HEAD(&pt->link);
249
250 spin_lock_irq(&obj->lock);
251 if (!dma_fence_is_signaled_locked(&pt->base)) {
252 struct rb_node **p = &obj->pt_tree.rb_node;
253 struct rb_node *parent = NULL;
254
255 while (*p) {
256 struct sync_pt *other;
257 int cmp;
258
259 parent = *p;
260 other = rb_entry(parent, typeof(*pt), node);
261 cmp = value - other->base.seqno;
262 if (cmp > 0) {
263 p = &parent->rb_right;
264 } else if (cmp < 0) {
265 p = &parent->rb_left;
266 } else {
267 if (dma_fence_get_rcu(&other->base)) {
268 dma_fence_put(&pt->base);
269 pt = other;
270 goto unlock;
271 }
272 p = &parent->rb_left;
273 }
274 }
275 rb_link_node(&pt->node, parent, p);
276 rb_insert_color(&pt->node, &obj->pt_tree);
277
278 parent = rb_next(&pt->node);
279 list_add_tail(&pt->link,
280 parent ? &rb_entry(parent, typeof(*pt), node)->link : &obj->pt_list);
281 }
282unlock:
283 spin_unlock_irq(&obj->lock);
284
285 return pt;
286}
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294
295static int sw_sync_debugfs_open(struct inode *inode, struct file *file)
296{
297 struct sync_timeline *obj;
298 char task_comm[TASK_COMM_LEN];
299
300 get_task_comm(task_comm, current);
301
302 obj = sync_timeline_create(task_comm);
303 if (!obj)
304 return -ENOMEM;
305
306 file->private_data = obj;
307
308 return 0;
309}
310
311static int sw_sync_debugfs_release(struct inode *inode, struct file *file)
312{
313 struct sync_timeline *obj = file->private_data;
314 struct sync_pt *pt, *next;
315
316 spin_lock_irq(&obj->lock);
317
318 list_for_each_entry_safe(pt, next, &obj->pt_list, link) {
319 dma_fence_set_error(&pt->base, -ENOENT);
320 dma_fence_signal_locked(&pt->base);
321 }
322
323 spin_unlock_irq(&obj->lock);
324
325 sync_timeline_put(obj);
326 return 0;
327}
328
329static long sw_sync_ioctl_create_fence(struct sync_timeline *obj,
330 unsigned long arg)
331{
332 int fd = get_unused_fd_flags(O_CLOEXEC);
333 int err;
334 struct sync_pt *pt;
335 struct sync_file *sync_file;
336 struct sw_sync_create_fence_data data;
337
338 if (fd < 0)
339 return fd;
340
341 if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
342 err = -EFAULT;
343 goto err;
344 }
345
346 pt = sync_pt_create(obj, data.value);
347 if (!pt) {
348 err = -ENOMEM;
349 goto err;
350 }
351
352 sync_file = sync_file_create(&pt->base);
353 dma_fence_put(&pt->base);
354 if (!sync_file) {
355 err = -ENOMEM;
356 goto err;
357 }
358
359 data.fence = fd;
360 if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
361 fput(sync_file->file);
362 err = -EFAULT;
363 goto err;
364 }
365
366 fd_install(fd, sync_file->file);
367
368 return 0;
369
370err:
371 put_unused_fd(fd);
372 return err;
373}
374
375static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg)
376{
377 u32 value;
378
379 if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
380 return -EFAULT;
381
382 while (value > INT_MAX) {
383 sync_timeline_signal(obj, INT_MAX);
384 value -= INT_MAX;
385 }
386
387 sync_timeline_signal(obj, value);
388
389 return 0;
390}
391
392static long sw_sync_ioctl(struct file *file, unsigned int cmd,
393 unsigned long arg)
394{
395 struct sync_timeline *obj = file->private_data;
396
397 switch (cmd) {
398 case SW_SYNC_IOC_CREATE_FENCE:
399 return sw_sync_ioctl_create_fence(obj, arg);
400
401 case SW_SYNC_IOC_INC:
402 return sw_sync_ioctl_inc(obj, arg);
403
404 default:
405 return -ENOTTY;
406 }
407}
408
409const struct file_operations sw_sync_debugfs_fops = {
410 .open = sw_sync_debugfs_open,
411 .release = sw_sync_debugfs_release,
412 .unlocked_ioctl = sw_sync_ioctl,
413 .compat_ioctl = sw_sync_ioctl,
414};
415