blob: 09f948fd62addc013b9fd7697169b055e208fbee [file] [log] [blame]
Sumit Semwald15bd7e2011-12-26 14:53:15 +05301/*
2 * Framework for buffer objects that can be shared across devices/subsystems.
3 *
4 * Copyright(C) 2011 Linaro Limited. All rights reserved.
5 * Author: Sumit Semwal <sumit.semwal@ti.com>
6 *
7 * Many thanks to linaro-mm-sig list, and specially
8 * Arnd Bergmann <arnd@arndb.de>, Rob Clark <rob@ti.com> and
9 * Daniel Vetter <daniel@ffwll.ch> for their support in creation and
10 * refining of this idea.
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License version 2 as published by
14 * the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful, but WITHOUT
17 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
19 * more details.
20 *
21 * You should have received a copy of the GNU General Public License along with
22 * this program. If not, see <http://www.gnu.org/licenses/>.
23 */
24
25#include <linux/fs.h>
26#include <linux/slab.h>
27#include <linux/dma-buf.h>
Chris Wilsonf54d1862016-10-25 13:00:45 +010028#include <linux/dma-fence.h>
Sumit Semwald15bd7e2011-12-26 14:53:15 +053029#include <linux/anon_inodes.h>
30#include <linux/export.h>
Sumit Semwalb89e3562013-04-04 11:44:37 +053031#include <linux/debugfs.h>
Sumit Semwal9abdffe2015-05-05 14:56:15 +053032#include <linux/module.h>
Sumit Semwalb89e3562013-04-04 11:44:37 +053033#include <linux/seq_file.h>
Maarten Lankhorst9b495a52014-07-01 12:57:43 +020034#include <linux/poll.h>
Maarten Lankhorst3aac4502014-07-01 12:57:26 +020035#include <linux/reservation.h>
Muhammad Falak R Wanib02da6f2016-05-23 17:08:42 +053036#include <linux/mm.h>
Sumit Semwald15bd7e2011-12-26 14:53:15 +053037
Daniel Vetterc11e3912016-02-11 20:04:51 -020038#include <uapi/linux/dma-buf.h>
39
Sumit Semwald15bd7e2011-12-26 14:53:15 +053040static inline int is_dma_buf_file(struct file *);
41
Sumit Semwalb89e3562013-04-04 11:44:37 +053042struct dma_buf_list {
43 struct list_head head;
44 struct mutex lock;
45};
46
47static struct dma_buf_list db_list;
48
Sumit Semwald15bd7e2011-12-26 14:53:15 +053049static int dma_buf_release(struct inode *inode, struct file *file)
50{
51 struct dma_buf *dmabuf;
52
53 if (!is_dma_buf_file(file))
54 return -EINVAL;
55
56 dmabuf = file->private_data;
57
Daniel Vetterf00b4da2012-12-20 14:14:23 +010058 BUG_ON(dmabuf->vmapping_counter);
59
Maarten Lankhorst9b495a52014-07-01 12:57:43 +020060 /*
61 * Any fences that a dma-buf poll can wait on should be signaled
62 * before releasing dma-buf. This is the responsibility of each
63 * driver that uses the reservation objects.
64 *
65 * If you hit this BUG() it means someone dropped their ref to the
66 * dma-buf while still having pending operation to the buffer.
67 */
68 BUG_ON(dmabuf->cb_shared.active || dmabuf->cb_excl.active);
69
Sumit Semwald15bd7e2011-12-26 14:53:15 +053070 dmabuf->ops->release(dmabuf);
Sumit Semwalb89e3562013-04-04 11:44:37 +053071
72 mutex_lock(&db_list.lock);
73 list_del(&dmabuf->list_node);
74 mutex_unlock(&db_list.lock);
75
Maarten Lankhorst3aac4502014-07-01 12:57:26 +020076 if (dmabuf->resv == (struct reservation_object *)&dmabuf[1])
77 reservation_object_fini(dmabuf->resv);
78
Sumit Semwal9abdffe2015-05-05 14:56:15 +053079 module_put(dmabuf->owner);
Sumit Semwald15bd7e2011-12-26 14:53:15 +053080 kfree(dmabuf);
81 return 0;
82}
83
Daniel Vetter4c785132012-04-24 14:38:52 +053084static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
85{
86 struct dma_buf *dmabuf;
87
88 if (!is_dma_buf_file(file))
89 return -EINVAL;
90
91 dmabuf = file->private_data;
92
93 /* check for overflowing the buffer's size */
Muhammad Falak R Wanib02da6f2016-05-23 17:08:42 +053094 if (vma->vm_pgoff + vma_pages(vma) >
Daniel Vetter4c785132012-04-24 14:38:52 +053095 dmabuf->size >> PAGE_SHIFT)
96 return -EINVAL;
97
98 return dmabuf->ops->mmap(dmabuf, vma);
99}
100
Christopher James Halse Rogers19e86972013-09-10 11:36:45 +0530101static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence)
102{
103 struct dma_buf *dmabuf;
104 loff_t base;
105
106 if (!is_dma_buf_file(file))
107 return -EBADF;
108
109 dmabuf = file->private_data;
110
111 /* only support discovering the end of the buffer,
112 but also allow SEEK_SET to maintain the idiomatic
113 SEEK_END(0), SEEK_CUR(0) pattern */
114 if (whence == SEEK_END)
115 base = dmabuf->size;
116 else if (whence == SEEK_SET)
117 base = 0;
118 else
119 return -EINVAL;
120
121 if (offset != 0)
122 return -EINVAL;
123
124 return base + offset;
125}
126
Chris Wilsonf54d1862016-10-25 13:00:45 +0100127static void dma_buf_poll_cb(struct dma_fence *fence, struct dma_fence_cb *cb)
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200128{
129 struct dma_buf_poll_cb_t *dcb = (struct dma_buf_poll_cb_t *)cb;
130 unsigned long flags;
131
132 spin_lock_irqsave(&dcb->poll->lock, flags);
133 wake_up_locked_poll(dcb->poll, dcb->active);
134 dcb->active = 0;
135 spin_unlock_irqrestore(&dcb->poll->lock, flags);
136}
137
138static unsigned int dma_buf_poll(struct file *file, poll_table *poll)
139{
140 struct dma_buf *dmabuf;
141 struct reservation_object *resv;
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200142 struct reservation_object_list *fobj;
Chris Wilsonf54d1862016-10-25 13:00:45 +0100143 struct dma_fence *fence_excl;
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200144 unsigned long events;
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200145 unsigned shared_count, seq;
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200146
147 dmabuf = file->private_data;
148 if (!dmabuf || !dmabuf->resv)
149 return POLLERR;
150
151 resv = dmabuf->resv;
152
153 poll_wait(file, &dmabuf->poll, poll);
154
155 events = poll_requested_events(poll) & (POLLIN | POLLOUT);
156 if (!events)
157 return 0;
158
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200159retry:
160 seq = read_seqcount_begin(&resv->seq);
161 rcu_read_lock();
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200162
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200163 fobj = rcu_dereference(resv->fence);
164 if (fobj)
165 shared_count = fobj->shared_count;
166 else
167 shared_count = 0;
168 fence_excl = rcu_dereference(resv->fence_excl);
169 if (read_seqcount_retry(&resv->seq, seq)) {
170 rcu_read_unlock();
171 goto retry;
172 }
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200173
174 if (fence_excl && (!(events & POLLOUT) || shared_count == 0)) {
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200175 struct dma_buf_poll_cb_t *dcb = &dmabuf->cb_excl;
176 unsigned long pevents = POLLIN;
177
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200178 if (shared_count == 0)
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200179 pevents |= POLLOUT;
180
181 spin_lock_irq(&dmabuf->poll.lock);
182 if (dcb->active) {
183 dcb->active |= pevents;
184 events &= ~pevents;
185 } else
186 dcb->active = pevents;
187 spin_unlock_irq(&dmabuf->poll.lock);
188
189 if (events & pevents) {
Chris Wilsonf54d1862016-10-25 13:00:45 +0100190 if (!dma_fence_get_rcu(fence_excl)) {
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200191 /* force a recheck */
192 events &= ~pevents;
193 dma_buf_poll_cb(NULL, &dcb->cb);
Chris Wilsonf54d1862016-10-25 13:00:45 +0100194 } else if (!dma_fence_add_callback(fence_excl, &dcb->cb,
195 dma_buf_poll_cb)) {
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200196 events &= ~pevents;
Chris Wilsonf54d1862016-10-25 13:00:45 +0100197 dma_fence_put(fence_excl);
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200198 } else {
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200199 /*
200 * No callback queued, wake up any additional
201 * waiters.
202 */
Chris Wilsonf54d1862016-10-25 13:00:45 +0100203 dma_fence_put(fence_excl);
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200204 dma_buf_poll_cb(NULL, &dcb->cb);
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200205 }
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200206 }
207 }
208
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200209 if ((events & POLLOUT) && shared_count > 0) {
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200210 struct dma_buf_poll_cb_t *dcb = &dmabuf->cb_shared;
211 int i;
212
213 /* Only queue a new callback if no event has fired yet */
214 spin_lock_irq(&dmabuf->poll.lock);
215 if (dcb->active)
216 events &= ~POLLOUT;
217 else
218 dcb->active = POLLOUT;
219 spin_unlock_irq(&dmabuf->poll.lock);
220
221 if (!(events & POLLOUT))
222 goto out;
223
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200224 for (i = 0; i < shared_count; ++i) {
Chris Wilsonf54d1862016-10-25 13:00:45 +0100225 struct dma_fence *fence = rcu_dereference(fobj->shared[i]);
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200226
Chris Wilsonf54d1862016-10-25 13:00:45 +0100227 if (!dma_fence_get_rcu(fence)) {
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200228 /*
229 * fence refcount dropped to zero, this means
230 * that fobj has been freed
231 *
232 * call dma_buf_poll_cb and force a recheck!
233 */
234 events &= ~POLLOUT;
235 dma_buf_poll_cb(NULL, &dcb->cb);
236 break;
237 }
Chris Wilsonf54d1862016-10-25 13:00:45 +0100238 if (!dma_fence_add_callback(fence, &dcb->cb,
239 dma_buf_poll_cb)) {
240 dma_fence_put(fence);
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200241 events &= ~POLLOUT;
242 break;
243 }
Chris Wilsonf54d1862016-10-25 13:00:45 +0100244 dma_fence_put(fence);
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200245 }
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200246
247 /* No callback queued, wake up any additional waiters. */
Maarten Lankhorst04a5faa2014-07-01 12:57:54 +0200248 if (i == shared_count)
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200249 dma_buf_poll_cb(NULL, &dcb->cb);
250 }
251
252out:
Maarten Lankhorst3c3b1772014-07-01 12:58:00 +0200253 rcu_read_unlock();
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200254 return events;
255}
256
Daniel Vetterc11e3912016-02-11 20:04:51 -0200257static long dma_buf_ioctl(struct file *file,
258 unsigned int cmd, unsigned long arg)
259{
260 struct dma_buf *dmabuf;
261 struct dma_buf_sync sync;
262 enum dma_data_direction direction;
Chris Wilson18b862d2016-03-18 20:02:39 +0000263 int ret;
Daniel Vetterc11e3912016-02-11 20:04:51 -0200264
265 dmabuf = file->private_data;
266
267 switch (cmd) {
268 case DMA_BUF_IOCTL_SYNC:
269 if (copy_from_user(&sync, (void __user *) arg, sizeof(sync)))
270 return -EFAULT;
271
272 if (sync.flags & ~DMA_BUF_SYNC_VALID_FLAGS_MASK)
273 return -EINVAL;
274
275 switch (sync.flags & DMA_BUF_SYNC_RW) {
276 case DMA_BUF_SYNC_READ:
277 direction = DMA_FROM_DEVICE;
278 break;
279 case DMA_BUF_SYNC_WRITE:
280 direction = DMA_TO_DEVICE;
281 break;
282 case DMA_BUF_SYNC_RW:
283 direction = DMA_BIDIRECTIONAL;
284 break;
285 default:
286 return -EINVAL;
287 }
288
289 if (sync.flags & DMA_BUF_SYNC_END)
Chris Wilson18b862d2016-03-18 20:02:39 +0000290 ret = dma_buf_end_cpu_access(dmabuf, direction);
Daniel Vetterc11e3912016-02-11 20:04:51 -0200291 else
Chris Wilson18b862d2016-03-18 20:02:39 +0000292 ret = dma_buf_begin_cpu_access(dmabuf, direction);
Daniel Vetterc11e3912016-02-11 20:04:51 -0200293
Chris Wilson18b862d2016-03-18 20:02:39 +0000294 return ret;
Daniel Vetterc11e3912016-02-11 20:04:51 -0200295 default:
296 return -ENOTTY;
297 }
298}
299
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530300static const struct file_operations dma_buf_fops = {
301 .release = dma_buf_release,
Daniel Vetter4c785132012-04-24 14:38:52 +0530302 .mmap = dma_buf_mmap_internal,
Christopher James Halse Rogers19e86972013-09-10 11:36:45 +0530303 .llseek = dma_buf_llseek,
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200304 .poll = dma_buf_poll,
Daniel Vetterc11e3912016-02-11 20:04:51 -0200305 .unlocked_ioctl = dma_buf_ioctl,
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530306};
307
308/*
309 * is_dma_buf_file - Check if struct file* is associated with dma_buf
310 */
311static inline int is_dma_buf_file(struct file *file)
312{
313 return file->f_op == &dma_buf_fops;
314}
315
316/**
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100317 * DOC: dma buf device access
318 *
319 * For device DMA access to a shared DMA buffer the usual sequence of operations
320 * is fairly simple:
321 *
322 * 1. The exporter defines his exporter instance using
323 * DEFINE_DMA_BUF_EXPORT_INFO() and calls dma_buf_export() to wrap a private
324 * buffer object into a &dma_buf. It then exports that &dma_buf to userspace
325 * as a file descriptor by calling dma_buf_fd().
326 *
327 * 2. Userspace passes this file-descriptors to all drivers it wants this buffer
328 * to share with: First the filedescriptor is converted to a &dma_buf using
329 * dma_buf_get(). The the buffer is attached to the device using
330 * dma_buf_attach().
331 *
332 * Up to this stage the exporter is still free to migrate or reallocate the
333 * backing storage.
334 *
335 * 3. Once the buffer is attached to all devices userspace can inniate DMA
336 * access to the shared buffer. In the kernel this is done by calling
337 * dma_buf_map_attachment() and dma_buf_unmap_attachment().
338 *
339 * 4. Once a driver is done with a shared buffer it needs to call
340 * dma_buf_detach() (after cleaning up any mappings) and then release the
341 * reference acquired with dma_buf_get by calling dma_buf_put().
342 *
343 * For the detailed semantics exporters are expected to implement see
344 * &dma_buf_ops.
345 */
346
347/**
Sumit Semwald8fbe342015-01-23 12:53:43 +0530348 * dma_buf_export - Creates a new dma_buf, and associates an anon file
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530349 * with this buffer, so it can be exported.
350 * Also connect the allocator specific data and ops to the buffer.
Sumit Semwal78df9692013-03-22 18:22:16 +0530351 * Additionally, provide a name string for exporter; useful in debugging.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530352 *
Sumit Semwald8fbe342015-01-23 12:53:43 +0530353 * @exp_info: [in] holds all the export related information provided
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100354 * by the exporter. see struct &dma_buf_export_info
Sumit Semwald8fbe342015-01-23 12:53:43 +0530355 * for further details.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530356 *
357 * Returns, on success, a newly created dma_buf object, which wraps the
358 * supplied private data and operations for dma_buf_ops. On either missing
359 * ops, or error in allocating struct dma_buf, will return negative error.
360 *
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100361 * For most cases the easiest way to create @exp_info is through the
362 * %DEFINE_DMA_BUF_EXPORT_INFO macro.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530363 */
Sumit Semwald8fbe342015-01-23 12:53:43 +0530364struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530365{
366 struct dma_buf *dmabuf;
Sumit Semwald8fbe342015-01-23 12:53:43 +0530367 struct reservation_object *resv = exp_info->resv;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530368 struct file *file;
Maarten Lankhorst3aac4502014-07-01 12:57:26 +0200369 size_t alloc_size = sizeof(struct dma_buf);
Chris Wilsona026df42016-07-18 12:16:22 +0100370 int ret;
Jagan Teki51366292015-05-21 01:09:31 +0530371
Sumit Semwald8fbe342015-01-23 12:53:43 +0530372 if (!exp_info->resv)
Maarten Lankhorst3aac4502014-07-01 12:57:26 +0200373 alloc_size += sizeof(struct reservation_object);
374 else
375 /* prevent &dma_buf[1] == dma_buf->resv */
376 alloc_size += 1;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530377
Sumit Semwald8fbe342015-01-23 12:53:43 +0530378 if (WARN_ON(!exp_info->priv
379 || !exp_info->ops
380 || !exp_info->ops->map_dma_buf
381 || !exp_info->ops->unmap_dma_buf
382 || !exp_info->ops->release
383 || !exp_info->ops->kmap_atomic
384 || !exp_info->ops->kmap
385 || !exp_info->ops->mmap)) {
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530386 return ERR_PTR(-EINVAL);
387 }
388
Sumit Semwal9abdffe2015-05-05 14:56:15 +0530389 if (!try_module_get(exp_info->owner))
390 return ERR_PTR(-ENOENT);
391
Maarten Lankhorst3aac4502014-07-01 12:57:26 +0200392 dmabuf = kzalloc(alloc_size, GFP_KERNEL);
Sumit Semwal9abdffe2015-05-05 14:56:15 +0530393 if (!dmabuf) {
Chris Wilsona026df42016-07-18 12:16:22 +0100394 ret = -ENOMEM;
395 goto err_module;
Sumit Semwal9abdffe2015-05-05 14:56:15 +0530396 }
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530397
Sumit Semwald8fbe342015-01-23 12:53:43 +0530398 dmabuf->priv = exp_info->priv;
399 dmabuf->ops = exp_info->ops;
400 dmabuf->size = exp_info->size;
401 dmabuf->exp_name = exp_info->exp_name;
Sumit Semwal9abdffe2015-05-05 14:56:15 +0530402 dmabuf->owner = exp_info->owner;
Maarten Lankhorst9b495a52014-07-01 12:57:43 +0200403 init_waitqueue_head(&dmabuf->poll);
404 dmabuf->cb_excl.poll = dmabuf->cb_shared.poll = &dmabuf->poll;
405 dmabuf->cb_excl.active = dmabuf->cb_shared.active = 0;
406
Maarten Lankhorst3aac4502014-07-01 12:57:26 +0200407 if (!resv) {
408 resv = (struct reservation_object *)&dmabuf[1];
409 reservation_object_init(resv);
410 }
411 dmabuf->resv = resv;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530412
Sumit Semwald8fbe342015-01-23 12:53:43 +0530413 file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf,
414 exp_info->flags);
Tuomas Tynkkynen9022e242013-08-27 16:30:38 +0300415 if (IS_ERR(file)) {
Chris Wilsona026df42016-07-18 12:16:22 +0100416 ret = PTR_ERR(file);
417 goto err_dmabuf;
Tuomas Tynkkynen9022e242013-08-27 16:30:38 +0300418 }
Christopher James Halse Rogers19e86972013-09-10 11:36:45 +0530419
420 file->f_mode |= FMODE_LSEEK;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530421 dmabuf->file = file;
422
423 mutex_init(&dmabuf->lock);
424 INIT_LIST_HEAD(&dmabuf->attachments);
425
Sumit Semwalb89e3562013-04-04 11:44:37 +0530426 mutex_lock(&db_list.lock);
427 list_add(&dmabuf->list_node, &db_list.head);
428 mutex_unlock(&db_list.lock);
429
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530430 return dmabuf;
Chris Wilsona026df42016-07-18 12:16:22 +0100431
432err_dmabuf:
433 kfree(dmabuf);
434err_module:
435 module_put(exp_info->owner);
436 return ERR_PTR(ret);
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530437}
Sumit Semwald8fbe342015-01-23 12:53:43 +0530438EXPORT_SYMBOL_GPL(dma_buf_export);
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530439
440/**
441 * dma_buf_fd - returns a file descriptor for the given dma_buf
442 * @dmabuf: [in] pointer to dma_buf for which fd is required.
Dave Airlie55c1c4c2012-03-16 10:34:02 +0000443 * @flags: [in] flags to give to fd
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530444 *
445 * On success, returns an associated 'fd'. Else, returns error.
446 */
Dave Airlie55c1c4c2012-03-16 10:34:02 +0000447int dma_buf_fd(struct dma_buf *dmabuf, int flags)
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530448{
Borislav Petkovf5e097f2012-12-11 16:05:26 +0100449 int fd;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530450
451 if (!dmabuf || !dmabuf->file)
452 return -EINVAL;
453
Borislav Petkovf5e097f2012-12-11 16:05:26 +0100454 fd = get_unused_fd_flags(flags);
455 if (fd < 0)
456 return fd;
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530457
458 fd_install(fd, dmabuf->file);
459
460 return fd;
461}
462EXPORT_SYMBOL_GPL(dma_buf_fd);
463
464/**
465 * dma_buf_get - returns the dma_buf structure related to an fd
466 * @fd: [in] fd associated with the dma_buf to be returned
467 *
468 * On success, returns the dma_buf structure associated with an fd; uses
469 * file's refcounting done by fget to increase refcount. returns ERR_PTR
470 * otherwise.
471 */
472struct dma_buf *dma_buf_get(int fd)
473{
474 struct file *file;
475
476 file = fget(fd);
477
478 if (!file)
479 return ERR_PTR(-EBADF);
480
481 if (!is_dma_buf_file(file)) {
482 fput(file);
483 return ERR_PTR(-EINVAL);
484 }
485
486 return file->private_data;
487}
488EXPORT_SYMBOL_GPL(dma_buf_get);
489
490/**
491 * dma_buf_put - decreases refcount of the buffer
492 * @dmabuf: [in] buffer to reduce refcount of
493 *
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100494 * Uses file's refcounting done implicitly by fput().
495 *
496 * If, as a result of this call, the refcount becomes 0, the 'release' file
497 * operation related to this fd is called. It calls the release operation of
498 * struct &dma_buf_ops in turn, and frees the memory allocated for dmabuf when
499 * exported.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530500 */
501void dma_buf_put(struct dma_buf *dmabuf)
502{
503 if (WARN_ON(!dmabuf || !dmabuf->file))
504 return;
505
506 fput(dmabuf->file);
507}
508EXPORT_SYMBOL_GPL(dma_buf_put);
509
510/**
511 * dma_buf_attach - Add the device to dma_buf's attachments list; optionally,
512 * calls attach() of dma_buf_ops to allow device-specific attach functionality
513 * @dmabuf: [in] buffer to attach device to.
514 * @dev: [in] device to be attached.
515 *
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100516 * Returns struct dma_buf_attachment pointer for this attachment. Attachments
517 * must be cleaned up by calling dma_buf_detach().
518 *
519 * Returns:
520 *
521 * A pointer to newly created &dma_buf_attachment on success, or a negative
522 * error code wrapped into a pointer on failure.
523 *
524 * Note that this can fail if the backing storage of @dmabuf is in a place not
525 * accessible to @dev, and cannot be moved to a more suitable place. This is
526 * indicated with the error code -EBUSY.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530527 */
528struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
529 struct device *dev)
530{
531 struct dma_buf_attachment *attach;
532 int ret;
533
Laurent Pinchartd1aa06a2012-01-26 12:27:23 +0100534 if (WARN_ON(!dmabuf || !dev))
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530535 return ERR_PTR(-EINVAL);
536
537 attach = kzalloc(sizeof(struct dma_buf_attachment), GFP_KERNEL);
538 if (attach == NULL)
Laurent Pincharta9fbc3b2012-01-26 12:27:24 +0100539 return ERR_PTR(-ENOMEM);
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530540
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530541 attach->dev = dev;
542 attach->dmabuf = dmabuf;
Laurent Pinchart2ed92012012-01-26 12:27:25 +0100543
544 mutex_lock(&dmabuf->lock);
545
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530546 if (dmabuf->ops->attach) {
547 ret = dmabuf->ops->attach(dmabuf, dev, attach);
548 if (ret)
549 goto err_attach;
550 }
551 list_add(&attach->node, &dmabuf->attachments);
552
553 mutex_unlock(&dmabuf->lock);
554 return attach;
555
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530556err_attach:
557 kfree(attach);
558 mutex_unlock(&dmabuf->lock);
559 return ERR_PTR(ret);
560}
561EXPORT_SYMBOL_GPL(dma_buf_attach);
562
563/**
564 * dma_buf_detach - Remove the given attachment from dmabuf's attachments list;
565 * optionally calls detach() of dma_buf_ops for device-specific detach
566 * @dmabuf: [in] buffer to detach from.
567 * @attach: [in] attachment to be detached; is free'd after this call.
568 *
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100569 * Clean up a device attachment obtained by calling dma_buf_attach().
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530570 */
571void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach)
572{
Laurent Pinchartd1aa06a2012-01-26 12:27:23 +0100573 if (WARN_ON(!dmabuf || !attach))
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530574 return;
575
576 mutex_lock(&dmabuf->lock);
577 list_del(&attach->node);
578 if (dmabuf->ops->detach)
579 dmabuf->ops->detach(dmabuf, attach);
580
581 mutex_unlock(&dmabuf->lock);
582 kfree(attach);
583}
584EXPORT_SYMBOL_GPL(dma_buf_detach);
585
586/**
587 * dma_buf_map_attachment - Returns the scatterlist table of the attachment;
588 * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the
589 * dma_buf_ops.
590 * @attach: [in] attachment whose scatterlist is to be returned
591 * @direction: [in] direction of DMA transfer
592 *
Colin Crossfee0c542013-12-20 16:43:50 -0800593 * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100594 * on error. May return -EINTR if it is interrupted by a signal.
595 *
596 * A mapping must be unmapped again using dma_buf_map_attachment(). Note that
597 * the underlying backing storage is pinned for as long as a mapping exists,
598 * therefore users/importers should not hold onto a mapping for undue amounts of
599 * time.
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530600 */
601struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach,
602 enum dma_data_direction direction)
603{
604 struct sg_table *sg_table = ERR_PTR(-EINVAL);
605
606 might_sleep();
607
Laurent Pinchartd1aa06a2012-01-26 12:27:23 +0100608 if (WARN_ON(!attach || !attach->dmabuf))
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530609 return ERR_PTR(-EINVAL);
610
Laurent Pinchartd1aa06a2012-01-26 12:27:23 +0100611 sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction);
Colin Crossfee0c542013-12-20 16:43:50 -0800612 if (!sg_table)
613 sg_table = ERR_PTR(-ENOMEM);
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530614
615 return sg_table;
616}
617EXPORT_SYMBOL_GPL(dma_buf_map_attachment);
618
619/**
620 * dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might
621 * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of
622 * dma_buf_ops.
623 * @attach: [in] attachment to unmap buffer from
624 * @sg_table: [in] scatterlist info of the buffer to unmap
Sumit Semwal33ea2dc2012-01-27 15:09:27 +0530625 * @direction: [in] direction of DMA transfer
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530626 *
Daniel Vetter2904a8c2016-12-09 19:53:07 +0100627 * This unmaps a DMA mapping for @attached obtained by dma_buf_map_attachment().
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530628 */
629void dma_buf_unmap_attachment(struct dma_buf_attachment *attach,
Sumit Semwal33ea2dc2012-01-27 15:09:27 +0530630 struct sg_table *sg_table,
631 enum dma_data_direction direction)
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530632{
Rob Clarkb6fa0cd2012-09-28 09:29:43 +0200633 might_sleep();
634
Laurent Pinchartd1aa06a2012-01-26 12:27:23 +0100635 if (WARN_ON(!attach || !attach->dmabuf || !sg_table))
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530636 return;
637
Sumit Semwal33ea2dc2012-01-27 15:09:27 +0530638 attach->dmabuf->ops->unmap_dma_buf(attach, sg_table,
639 direction);
Sumit Semwald15bd7e2011-12-26 14:53:15 +0530640}
641EXPORT_SYMBOL_GPL(dma_buf_unmap_attachment);
Daniel Vetterfc130202012-03-20 00:02:37 +0100642
Chris Wilsonae4e46b2016-08-15 16:42:18 +0100643static int __dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
644 enum dma_data_direction direction)
645{
646 bool write = (direction == DMA_BIDIRECTIONAL ||
647 direction == DMA_TO_DEVICE);
648 struct reservation_object *resv = dmabuf->resv;
649 long ret;
650
651 /* Wait on any implicit rendering fences */
652 ret = reservation_object_wait_timeout_rcu(resv, write, true,
653 MAX_SCHEDULE_TIMEOUT);
654 if (ret < 0)
655 return ret;
656
657 return 0;
658}
Daniel Vetterfc130202012-03-20 00:02:37 +0100659
660/**
661 * dma_buf_begin_cpu_access - Must be called before accessing a dma_buf from the
662 * cpu in the kernel context. Calls begin_cpu_access to allow exporter-specific
663 * preparations. Coherency is only guaranteed in the specified range for the
664 * specified access direction.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700665 * @dmabuf: [in] buffer to prepare cpu access for.
Daniel Vetterfc130202012-03-20 00:02:37 +0100666 * @direction: [in] length of range for cpu access.
667 *
668 * Can return negative error values, returns 0 on success.
669 */
Tiago Vignatti831e9da2015-12-22 19:36:45 -0200670int dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
Daniel Vetterfc130202012-03-20 00:02:37 +0100671 enum dma_data_direction direction)
672{
673 int ret = 0;
674
675 if (WARN_ON(!dmabuf))
676 return -EINVAL;
677
678 if (dmabuf->ops->begin_cpu_access)
Tiago Vignatti831e9da2015-12-22 19:36:45 -0200679 ret = dmabuf->ops->begin_cpu_access(dmabuf, direction);
Daniel Vetterfc130202012-03-20 00:02:37 +0100680
Chris Wilsonae4e46b2016-08-15 16:42:18 +0100681 /* Ensure that all fences are waited upon - but we first allow
682 * the native handler the chance to do so more efficiently if it
683 * chooses. A double invocation here will be reasonably cheap no-op.
684 */
685 if (ret == 0)
686 ret = __dma_buf_begin_cpu_access(dmabuf, direction);
687
Daniel Vetterfc130202012-03-20 00:02:37 +0100688 return ret;
689}
690EXPORT_SYMBOL_GPL(dma_buf_begin_cpu_access);
691
692/**
693 * dma_buf_end_cpu_access - Must be called after accessing a dma_buf from the
694 * cpu in the kernel context. Calls end_cpu_access to allow exporter-specific
695 * actions. Coherency is only guaranteed in the specified range for the
696 * specified access direction.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700697 * @dmabuf: [in] buffer to complete cpu access for.
Daniel Vetterfc130202012-03-20 00:02:37 +0100698 * @direction: [in] length of range for cpu access.
699 *
Daniel Vetter87e332d2016-03-21 08:24:22 +0100700 * Can return negative error values, returns 0 on success.
Daniel Vetterfc130202012-03-20 00:02:37 +0100701 */
Chris Wilson18b862d2016-03-18 20:02:39 +0000702int dma_buf_end_cpu_access(struct dma_buf *dmabuf,
703 enum dma_data_direction direction)
Daniel Vetterfc130202012-03-20 00:02:37 +0100704{
Chris Wilson18b862d2016-03-18 20:02:39 +0000705 int ret = 0;
706
Daniel Vetterfc130202012-03-20 00:02:37 +0100707 WARN_ON(!dmabuf);
708
709 if (dmabuf->ops->end_cpu_access)
Chris Wilson18b862d2016-03-18 20:02:39 +0000710 ret = dmabuf->ops->end_cpu_access(dmabuf, direction);
711
712 return ret;
Daniel Vetterfc130202012-03-20 00:02:37 +0100713}
714EXPORT_SYMBOL_GPL(dma_buf_end_cpu_access);
715
716/**
717 * dma_buf_kmap_atomic - Map a page of the buffer object into kernel address
718 * space. The same restrictions as for kmap_atomic and friends apply.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700719 * @dmabuf: [in] buffer to map page from.
Daniel Vetterfc130202012-03-20 00:02:37 +0100720 * @page_num: [in] page in PAGE_SIZE units to map.
721 *
722 * This call must always succeed, any necessary preparations that might fail
723 * need to be done in begin_cpu_access.
724 */
725void *dma_buf_kmap_atomic(struct dma_buf *dmabuf, unsigned long page_num)
726{
727 WARN_ON(!dmabuf);
728
729 return dmabuf->ops->kmap_atomic(dmabuf, page_num);
730}
731EXPORT_SYMBOL_GPL(dma_buf_kmap_atomic);
732
733/**
734 * dma_buf_kunmap_atomic - Unmap a page obtained by dma_buf_kmap_atomic.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700735 * @dmabuf: [in] buffer to unmap page from.
Daniel Vetterfc130202012-03-20 00:02:37 +0100736 * @page_num: [in] page in PAGE_SIZE units to unmap.
737 * @vaddr: [in] kernel space pointer obtained from dma_buf_kmap_atomic.
738 *
739 * This call must always succeed.
740 */
741void dma_buf_kunmap_atomic(struct dma_buf *dmabuf, unsigned long page_num,
742 void *vaddr)
743{
744 WARN_ON(!dmabuf);
745
746 if (dmabuf->ops->kunmap_atomic)
747 dmabuf->ops->kunmap_atomic(dmabuf, page_num, vaddr);
748}
749EXPORT_SYMBOL_GPL(dma_buf_kunmap_atomic);
750
751/**
752 * dma_buf_kmap - Map a page of the buffer object into kernel address space. The
753 * same restrictions as for kmap and friends apply.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700754 * @dmabuf: [in] buffer to map page from.
Daniel Vetterfc130202012-03-20 00:02:37 +0100755 * @page_num: [in] page in PAGE_SIZE units to map.
756 *
757 * This call must always succeed, any necessary preparations that might fail
758 * need to be done in begin_cpu_access.
759 */
760void *dma_buf_kmap(struct dma_buf *dmabuf, unsigned long page_num)
761{
762 WARN_ON(!dmabuf);
763
764 return dmabuf->ops->kmap(dmabuf, page_num);
765}
766EXPORT_SYMBOL_GPL(dma_buf_kmap);
767
768/**
769 * dma_buf_kunmap - Unmap a page obtained by dma_buf_kmap.
Randy Dunlapefb4df822012-04-17 17:03:30 -0700770 * @dmabuf: [in] buffer to unmap page from.
Daniel Vetterfc130202012-03-20 00:02:37 +0100771 * @page_num: [in] page in PAGE_SIZE units to unmap.
772 * @vaddr: [in] kernel space pointer obtained from dma_buf_kmap.
773 *
774 * This call must always succeed.
775 */
776void dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long page_num,
777 void *vaddr)
778{
779 WARN_ON(!dmabuf);
780
781 if (dmabuf->ops->kunmap)
782 dmabuf->ops->kunmap(dmabuf, page_num, vaddr);
783}
784EXPORT_SYMBOL_GPL(dma_buf_kunmap);
Daniel Vetter4c785132012-04-24 14:38:52 +0530785
786
787/**
788 * dma_buf_mmap - Setup up a userspace mmap with the given vma
Sumit Semwal12c47272012-05-23 15:27:40 +0530789 * @dmabuf: [in] buffer that should back the vma
Daniel Vetter4c785132012-04-24 14:38:52 +0530790 * @vma: [in] vma for the mmap
791 * @pgoff: [in] offset in pages where this mmap should start within the
Jagan Teki51366292015-05-21 01:09:31 +0530792 * dma-buf buffer.
Daniel Vetter4c785132012-04-24 14:38:52 +0530793 *
794 * This function adjusts the passed in vma so that it points at the file of the
Javier Martinez Canillasecf1dba2014-04-10 01:30:05 +0200795 * dma_buf operation. It also adjusts the starting pgoff and does bounds
Daniel Vetter4c785132012-04-24 14:38:52 +0530796 * checking on the size of the vma. Then it calls the exporters mmap function to
797 * set up the mapping.
798 *
799 * Can return negative error values, returns 0 on success.
800 */
801int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
802 unsigned long pgoff)
803{
John Sheu495c10c2013-02-11 17:50:24 -0800804 struct file *oldfile;
805 int ret;
806
Daniel Vetter4c785132012-04-24 14:38:52 +0530807 if (WARN_ON(!dmabuf || !vma))
808 return -EINVAL;
809
810 /* check for offset overflow */
Muhammad Falak R Wanib02da6f2016-05-23 17:08:42 +0530811 if (pgoff + vma_pages(vma) < pgoff)
Daniel Vetter4c785132012-04-24 14:38:52 +0530812 return -EOVERFLOW;
813
814 /* check for overflowing the buffer's size */
Muhammad Falak R Wanib02da6f2016-05-23 17:08:42 +0530815 if (pgoff + vma_pages(vma) >
Daniel Vetter4c785132012-04-24 14:38:52 +0530816 dmabuf->size >> PAGE_SHIFT)
817 return -EINVAL;
818
819 /* readjust the vma */
John Sheu495c10c2013-02-11 17:50:24 -0800820 get_file(dmabuf->file);
821 oldfile = vma->vm_file;
822 vma->vm_file = dmabuf->file;
Daniel Vetter4c785132012-04-24 14:38:52 +0530823 vma->vm_pgoff = pgoff;
824
John Sheu495c10c2013-02-11 17:50:24 -0800825 ret = dmabuf->ops->mmap(dmabuf, vma);
826 if (ret) {
827 /* restore old parameters on failure */
828 vma->vm_file = oldfile;
829 fput(dmabuf->file);
830 } else {
831 if (oldfile)
832 fput(oldfile);
833 }
834 return ret;
835
Daniel Vetter4c785132012-04-24 14:38:52 +0530836}
837EXPORT_SYMBOL_GPL(dma_buf_mmap);
Dave Airlie98f86c92012-05-20 12:33:56 +0530838
839/**
Sumit Semwal12c47272012-05-23 15:27:40 +0530840 * dma_buf_vmap - Create virtual mapping for the buffer object into kernel
841 * address space. Same restrictions as for vmap and friends apply.
842 * @dmabuf: [in] buffer to vmap
Dave Airlie98f86c92012-05-20 12:33:56 +0530843 *
844 * This call may fail due to lack of virtual mapping address space.
845 * These calls are optional in drivers. The intended use for them
846 * is for mapping objects linear in kernel space for high use objects.
847 * Please attempt to use kmap/kunmap before thinking about these interfaces.
Colin Crossfee0c542013-12-20 16:43:50 -0800848 *
849 * Returns NULL on error.
Dave Airlie98f86c92012-05-20 12:33:56 +0530850 */
851void *dma_buf_vmap(struct dma_buf *dmabuf)
852{
Daniel Vetterf00b4da2012-12-20 14:14:23 +0100853 void *ptr;
854
Dave Airlie98f86c92012-05-20 12:33:56 +0530855 if (WARN_ON(!dmabuf))
856 return NULL;
857
Daniel Vetterf00b4da2012-12-20 14:14:23 +0100858 if (!dmabuf->ops->vmap)
859 return NULL;
860
861 mutex_lock(&dmabuf->lock);
862 if (dmabuf->vmapping_counter) {
863 dmabuf->vmapping_counter++;
864 BUG_ON(!dmabuf->vmap_ptr);
865 ptr = dmabuf->vmap_ptr;
866 goto out_unlock;
867 }
868
869 BUG_ON(dmabuf->vmap_ptr);
870
871 ptr = dmabuf->ops->vmap(dmabuf);
Colin Crossfee0c542013-12-20 16:43:50 -0800872 if (WARN_ON_ONCE(IS_ERR(ptr)))
873 ptr = NULL;
874 if (!ptr)
Daniel Vetterf00b4da2012-12-20 14:14:23 +0100875 goto out_unlock;
876
877 dmabuf->vmap_ptr = ptr;
878 dmabuf->vmapping_counter = 1;
879
880out_unlock:
881 mutex_unlock(&dmabuf->lock);
882 return ptr;
Dave Airlie98f86c92012-05-20 12:33:56 +0530883}
884EXPORT_SYMBOL_GPL(dma_buf_vmap);
885
886/**
887 * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap.
Sumit Semwal12c47272012-05-23 15:27:40 +0530888 * @dmabuf: [in] buffer to vunmap
Randy Dunlap6e7b4a52012-06-09 15:02:59 -0700889 * @vaddr: [in] vmap to vunmap
Dave Airlie98f86c92012-05-20 12:33:56 +0530890 */
891void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
892{
893 if (WARN_ON(!dmabuf))
894 return;
895
Daniel Vetterf00b4da2012-12-20 14:14:23 +0100896 BUG_ON(!dmabuf->vmap_ptr);
897 BUG_ON(dmabuf->vmapping_counter == 0);
898 BUG_ON(dmabuf->vmap_ptr != vaddr);
899
900 mutex_lock(&dmabuf->lock);
901 if (--dmabuf->vmapping_counter == 0) {
902 if (dmabuf->ops->vunmap)
903 dmabuf->ops->vunmap(dmabuf, vaddr);
904 dmabuf->vmap_ptr = NULL;
905 }
906 mutex_unlock(&dmabuf->lock);
Dave Airlie98f86c92012-05-20 12:33:56 +0530907}
908EXPORT_SYMBOL_GPL(dma_buf_vunmap);
Sumit Semwalb89e3562013-04-04 11:44:37 +0530909
910#ifdef CONFIG_DEBUG_FS
Mathias Krauseeb0b9472016-06-19 14:31:29 +0200911static int dma_buf_debug_show(struct seq_file *s, void *unused)
Sumit Semwalb89e3562013-04-04 11:44:37 +0530912{
913 int ret;
914 struct dma_buf *buf_obj;
915 struct dma_buf_attachment *attach_obj;
916 int count = 0, attach_count;
917 size_t size = 0;
918
919 ret = mutex_lock_interruptible(&db_list.lock);
920
921 if (ret)
922 return ret;
923
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530924 seq_puts(s, "\nDma-buf Objects:\n");
925 seq_puts(s, "size\tflags\tmode\tcount\texp_name\n");
Sumit Semwalb89e3562013-04-04 11:44:37 +0530926
927 list_for_each_entry(buf_obj, &db_list.head, list_node) {
928 ret = mutex_lock_interruptible(&buf_obj->lock);
929
930 if (ret) {
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530931 seq_puts(s,
932 "\tERROR locking buffer object: skipping\n");
Sumit Semwalb89e3562013-04-04 11:44:37 +0530933 continue;
934 }
935
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530936 seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\n",
937 buf_obj->size,
Sumit Semwalb89e3562013-04-04 11:44:37 +0530938 buf_obj->file->f_flags, buf_obj->file->f_mode,
Al Viroa1f6dba2014-08-20 11:05:50 -0400939 file_count(buf_obj->file),
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530940 buf_obj->exp_name);
Sumit Semwalb89e3562013-04-04 11:44:37 +0530941
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530942 seq_puts(s, "\tAttached Devices:\n");
Sumit Semwalb89e3562013-04-04 11:44:37 +0530943 attach_count = 0;
944
945 list_for_each_entry(attach_obj, &buf_obj->attachments, node) {
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530946 seq_puts(s, "\t");
Sumit Semwalb89e3562013-04-04 11:44:37 +0530947
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530948 seq_printf(s, "%s\n", dev_name(attach_obj->dev));
Sumit Semwalb89e3562013-04-04 11:44:37 +0530949 attach_count++;
950 }
951
Sumit Semwalc0b00a52014-02-03 15:09:12 +0530952 seq_printf(s, "Total %d devices attached\n\n",
Sumit Semwalb89e3562013-04-04 11:44:37 +0530953 attach_count);
954
955 count++;
956 size += buf_obj->size;
957 mutex_unlock(&buf_obj->lock);
958 }
959
960 seq_printf(s, "\nTotal %d objects, %zu bytes\n", count, size);
961
962 mutex_unlock(&db_list.lock);
963 return 0;
964}
965
Sumit Semwalb89e3562013-04-04 11:44:37 +0530966static int dma_buf_debug_open(struct inode *inode, struct file *file)
967{
Mathias Krauseeb0b9472016-06-19 14:31:29 +0200968 return single_open(file, dma_buf_debug_show, NULL);
Sumit Semwalb89e3562013-04-04 11:44:37 +0530969}
970
971static const struct file_operations dma_buf_debug_fops = {
972 .open = dma_buf_debug_open,
973 .read = seq_read,
974 .llseek = seq_lseek,
975 .release = single_release,
976};
977
978static struct dentry *dma_buf_debugfs_dir;
979
980static int dma_buf_init_debugfs(void)
981{
Mathias Krausebd3e2202016-06-19 14:31:31 +0200982 struct dentry *d;
Sumit Semwalb89e3562013-04-04 11:44:37 +0530983 int err = 0;
Jagan Teki51366292015-05-21 01:09:31 +0530984
Mathias Krausebd3e2202016-06-19 14:31:31 +0200985 d = debugfs_create_dir("dma_buf", NULL);
986 if (IS_ERR(d))
987 return PTR_ERR(d);
Jagan Teki51366292015-05-21 01:09:31 +0530988
Mathias Krausebd3e2202016-06-19 14:31:31 +0200989 dma_buf_debugfs_dir = d;
Sumit Semwalb89e3562013-04-04 11:44:37 +0530990
Mathias Krausebd3e2202016-06-19 14:31:31 +0200991 d = debugfs_create_file("bufinfo", S_IRUGO, dma_buf_debugfs_dir,
992 NULL, &dma_buf_debug_fops);
993 if (IS_ERR(d)) {
Sumit Semwalb89e3562013-04-04 11:44:37 +0530994 pr_debug("dma_buf: debugfs: failed to create node bufinfo\n");
Mathias Krauseb7479992016-06-19 14:31:30 +0200995 debugfs_remove_recursive(dma_buf_debugfs_dir);
996 dma_buf_debugfs_dir = NULL;
Mathias Krausebd3e2202016-06-19 14:31:31 +0200997 err = PTR_ERR(d);
Mathias Krauseb7479992016-06-19 14:31:30 +0200998 }
Sumit Semwalb89e3562013-04-04 11:44:37 +0530999
1000 return err;
1001}
1002
1003static void dma_buf_uninit_debugfs(void)
1004{
1005 if (dma_buf_debugfs_dir)
1006 debugfs_remove_recursive(dma_buf_debugfs_dir);
1007}
Sumit Semwalb89e3562013-04-04 11:44:37 +05301008#else
1009static inline int dma_buf_init_debugfs(void)
1010{
1011 return 0;
1012}
1013static inline void dma_buf_uninit_debugfs(void)
1014{
1015}
1016#endif
1017
1018static int __init dma_buf_init(void)
1019{
1020 mutex_init(&db_list.lock);
1021 INIT_LIST_HEAD(&db_list.head);
1022 dma_buf_init_debugfs();
1023 return 0;
1024}
1025subsys_initcall(dma_buf_init);
1026
1027static void __exit dma_buf_deinit(void)
1028{
1029 dma_buf_uninit_debugfs();
1030}
1031__exitcall(dma_buf_deinit);