Commit | Line | Data |
---|---|---|
caab277b | 1 | // SPDX-License-Identifier: GPL-2.0-only |
d15bd7ee SS |
2 | /* |
3 | * Framework for buffer objects that can be shared across devices/subsystems. | |
4 | * | |
5 | * Copyright(C) 2011 Linaro Limited. All rights reserved. | |
6 | * Author: Sumit Semwal <sumit.semwal@ti.com> | |
7 | * | |
8 | * Many thanks to linaro-mm-sig list, and specially | |
9 | * Arnd Bergmann <arnd@arndb.de>, Rob Clark <rob@ti.com> and | |
10 | * Daniel Vetter <daniel@ffwll.ch> for their support in creation and | |
11 | * refining of this idea. | |
d15bd7ee SS |
12 | */ |
13 | ||
14 | #include <linux/fs.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/dma-buf.h> | |
f54d1867 | 17 | #include <linux/dma-fence.h> |
d15bd7ee SS |
18 | #include <linux/anon_inodes.h> |
19 | #include <linux/export.h> | |
b89e3563 | 20 | #include <linux/debugfs.h> |
9abdffe2 | 21 | #include <linux/module.h> |
b89e3563 | 22 | #include <linux/seq_file.h> |
9b495a58 | 23 | #include <linux/poll.h> |
52791eee | 24 | #include <linux/dma-resv.h> |
b02da6f8 | 25 | #include <linux/mm.h> |
ed63bb1d | 26 | #include <linux/mount.h> |
933a90bf | 27 | #include <linux/pseudo_fs.h> |
d15bd7ee | 28 | |
c11e391d | 29 | #include <uapi/linux/dma-buf.h> |
ed63bb1d | 30 | #include <uapi/linux/magic.h> |
c11e391d | 31 | |
bdb8d06d HV |
32 | #include "dma-buf-sysfs-stats.h" |
33 | ||
d15bd7ee SS |
34 | static inline int is_dma_buf_file(struct file *); |
35 | ||
b89e3563 SS |
36 | struct dma_buf_list { |
37 | struct list_head head; | |
38 | struct mutex lock; | |
39 | }; | |
40 | ||
41 | static struct dma_buf_list db_list; | |
42 | ||
bb2bb903 GH |
43 | static char *dmabuffs_dname(struct dentry *dentry, char *buffer, int buflen) |
44 | { | |
45 | struct dma_buf *dmabuf; | |
46 | char name[DMA_BUF_NAME_LEN]; | |
47 | size_t ret = 0; | |
48 | ||
49 | dmabuf = dentry->d_fsdata; | |
6348dd29 | 50 | spin_lock(&dmabuf->name_lock); |
bb2bb903 GH |
51 | if (dmabuf->name) |
52 | ret = strlcpy(name, dmabuf->name, DMA_BUF_NAME_LEN); | |
6348dd29 | 53 | spin_unlock(&dmabuf->name_lock); |
bb2bb903 GH |
54 | |
55 | return dynamic_dname(dentry, buffer, buflen, "/%s:%s", | |
56 | dentry->d_name.name, ret > 0 ? name : ""); | |
57 | } | |
58 | ||
4ab59c3c | 59 | static void dma_buf_release(struct dentry *dentry) |
d15bd7ee SS |
60 | { |
61 | struct dma_buf *dmabuf; | |
62 | ||
4ab59c3c | 63 | dmabuf = dentry->d_fsdata; |
19a508bd CTR |
64 | if (unlikely(!dmabuf)) |
65 | return; | |
d15bd7ee | 66 | |
f00b4dad DV |
67 | BUG_ON(dmabuf->vmapping_counter); |
68 | ||
9b495a58 | 69 | /* |
ff2d2384 MD |
70 | * If you hit this BUG() it could mean: |
71 | * * There's a file reference imbalance in dma_buf_poll / dma_buf_poll_cb or somewhere else | |
72 | * * dmabuf->cb_in/out.active are non-0 despite no pending fence callback | |
9b495a58 | 73 | */ |
6b51b02a | 74 | BUG_ON(dmabuf->cb_in.active || dmabuf->cb_out.active); |
9b495a58 | 75 | |
63c57e8d | 76 | dma_buf_stats_teardown(dmabuf); |
d15bd7ee | 77 | dmabuf->ops->release(dmabuf); |
b89e3563 | 78 | |
52791eee CK |
79 | if (dmabuf->resv == (struct dma_resv *)&dmabuf[1]) |
80 | dma_resv_fini(dmabuf->resv); | |
3aac4502 | 81 | |
f492283b | 82 | WARN_ON(!list_empty(&dmabuf->attachments)); |
9abdffe2 | 83 | module_put(dmabuf->owner); |
d1f37226 | 84 | kfree(dmabuf->name); |
d15bd7ee | 85 | kfree(dmabuf); |
4ab59c3c SS |
86 | } |
87 | ||
05cd8469 CTR |
88 | static int dma_buf_file_release(struct inode *inode, struct file *file) |
89 | { | |
90 | struct dma_buf *dmabuf; | |
91 | ||
92 | if (!is_dma_buf_file(file)) | |
93 | return -EINVAL; | |
94 | ||
95 | dmabuf = file->private_data; | |
96 | ||
97 | mutex_lock(&db_list.lock); | |
98 | list_del(&dmabuf->list_node); | |
99 | mutex_unlock(&db_list.lock); | |
100 | ||
101 | return 0; | |
102 | } | |
103 | ||
4ab59c3c SS |
104 | static const struct dentry_operations dma_buf_dentry_ops = { |
105 | .d_dname = dmabuffs_dname, | |
106 | .d_release = dma_buf_release, | |
107 | }; | |
108 | ||
109 | static struct vfsmount *dma_buf_mnt; | |
110 | ||
111 | static int dma_buf_fs_init_context(struct fs_context *fc) | |
112 | { | |
113 | struct pseudo_fs_context *ctx; | |
114 | ||
115 | ctx = init_pseudo(fc, DMA_BUF_MAGIC); | |
116 | if (!ctx) | |
117 | return -ENOMEM; | |
118 | ctx->dops = &dma_buf_dentry_ops; | |
d15bd7ee SS |
119 | return 0; |
120 | } | |
121 | ||
4ab59c3c SS |
122 | static struct file_system_type dma_buf_fs_type = { |
123 | .name = "dmabuf", | |
124 | .init_fs_context = dma_buf_fs_init_context, | |
125 | .kill_sb = kill_anon_super, | |
126 | }; | |
127 | ||
4c78513e DV |
128 | static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma) |
129 | { | |
130 | struct dma_buf *dmabuf; | |
131 | ||
132 | if (!is_dma_buf_file(file)) | |
133 | return -EINVAL; | |
134 | ||
135 | dmabuf = file->private_data; | |
136 | ||
e3a9d6c5 AD |
137 | /* check if buffer supports mmap */ |
138 | if (!dmabuf->ops->mmap) | |
139 | return -EINVAL; | |
140 | ||
4c78513e | 141 | /* check for overflowing the buffer's size */ |
b02da6f8 | 142 | if (vma->vm_pgoff + vma_pages(vma) > |
4c78513e DV |
143 | dmabuf->size >> PAGE_SHIFT) |
144 | return -EINVAL; | |
145 | ||
146 | return dmabuf->ops->mmap(dmabuf, vma); | |
147 | } | |
148 | ||
19e8697b CJHR |
149 | static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence) |
150 | { | |
151 | struct dma_buf *dmabuf; | |
152 | loff_t base; | |
153 | ||
154 | if (!is_dma_buf_file(file)) | |
155 | return -EBADF; | |
156 | ||
157 | dmabuf = file->private_data; | |
158 | ||
159 | /* only support discovering the end of the buffer, | |
160 | but also allow SEEK_SET to maintain the idiomatic | |
161 | SEEK_END(0), SEEK_CUR(0) pattern */ | |
162 | if (whence == SEEK_END) | |
163 | base = dmabuf->size; | |
164 | else if (whence == SEEK_SET) | |
165 | base = 0; | |
166 | else | |
167 | return -EINVAL; | |
168 | ||
169 | if (offset != 0) | |
170 | return -EINVAL; | |
171 | ||
172 | return base + offset; | |
173 | } | |
174 | ||
e7e21c72 | 175 | /** |
102514ec | 176 | * DOC: implicit fence polling |
e7e21c72 DV |
177 | * |
178 | * To support cross-device and cross-driver synchronization of buffer access | |
102514ec DV |
179 | * implicit fences (represented internally in the kernel with &struct dma_fence) |
180 | * can be attached to a &dma_buf. The glue for that and a few related things are | |
52791eee | 181 | * provided in the &dma_resv structure. |
e7e21c72 DV |
182 | * |
183 | * Userspace can query the state of these implicitly tracked fences using poll() | |
184 | * and related system calls: | |
185 | * | |
a9a08845 | 186 | * - Checking for EPOLLIN, i.e. read access, can be use to query the state of the |
e7e21c72 DV |
187 | * most recent write or exclusive fence. |
188 | * | |
a9a08845 | 189 | * - Checking for EPOLLOUT, i.e. write access, can be used to query the state of |
e7e21c72 DV |
190 | * all attached fences, shared and exclusive ones. |
191 | * | |
192 | * Note that this only signals the completion of the respective fences, i.e. the | |
193 | * DMA transfers are complete. Cache flushing and any other necessary | |
194 | * preparations before CPU access can begin still need to happen. | |
195 | */ | |
196 | ||
f54d1867 | 197 | static void dma_buf_poll_cb(struct dma_fence *fence, struct dma_fence_cb *cb) |
9b495a58 ML |
198 | { |
199 | struct dma_buf_poll_cb_t *dcb = (struct dma_buf_poll_cb_t *)cb; | |
ff2d2384 | 200 | struct dma_buf *dmabuf = container_of(dcb->poll, struct dma_buf, poll); |
9b495a58 ML |
201 | unsigned long flags; |
202 | ||
203 | spin_lock_irqsave(&dcb->poll->lock, flags); | |
204 | wake_up_locked_poll(dcb->poll, dcb->active); | |
205 | dcb->active = 0; | |
206 | spin_unlock_irqrestore(&dcb->poll->lock, flags); | |
6b51b02a | 207 | dma_fence_put(fence); |
ff2d2384 MD |
208 | /* Paired with get_file in dma_buf_poll */ |
209 | fput(dmabuf->file); | |
6b51b02a CK |
210 | } |
211 | ||
0a42016d | 212 | static bool dma_buf_poll_add_cb(struct dma_resv *resv, bool write, |
6b51b02a CK |
213 | struct dma_buf_poll_cb_t *dcb) |
214 | { | |
0a42016d | 215 | struct dma_resv_iter cursor; |
6b51b02a | 216 | struct dma_fence *fence; |
0a42016d | 217 | int r; |
6b51b02a | 218 | |
7bc80a54 CK |
219 | dma_resv_for_each_fence(&cursor, resv, dma_resv_usage_rw(write), |
220 | fence) { | |
6b51b02a CK |
221 | dma_fence_get(fence); |
222 | r = dma_fence_add_callback(fence, &dcb->cb, dma_buf_poll_cb); | |
223 | if (!r) | |
224 | return true; | |
225 | dma_fence_put(fence); | |
226 | } | |
227 | ||
228 | return false; | |
229 | } | |
230 | ||
afc9a42b | 231 | static __poll_t dma_buf_poll(struct file *file, poll_table *poll) |
9b495a58 ML |
232 | { |
233 | struct dma_buf *dmabuf; | |
52791eee | 234 | struct dma_resv *resv; |
01699437 | 235 | __poll_t events; |
9b495a58 ML |
236 | |
237 | dmabuf = file->private_data; | |
238 | if (!dmabuf || !dmabuf->resv) | |
a9a08845 | 239 | return EPOLLERR; |
9b495a58 ML |
240 | |
241 | resv = dmabuf->resv; | |
242 | ||
243 | poll_wait(file, &dmabuf->poll, poll); | |
244 | ||
a9a08845 | 245 | events = poll_requested_events(poll) & (EPOLLIN | EPOLLOUT); |
9b495a58 ML |
246 | if (!events) |
247 | return 0; | |
248 | ||
6b51b02a | 249 | dma_resv_lock(resv, NULL); |
9b495a58 | 250 | |
6b51b02a CK |
251 | if (events & EPOLLOUT) { |
252 | struct dma_buf_poll_cb_t *dcb = &dmabuf->cb_out; | |
9b495a58 | 253 | |
6b51b02a | 254 | /* Check that callback isn't busy */ |
9b495a58 | 255 | spin_lock_irq(&dmabuf->poll.lock); |
6b51b02a CK |
256 | if (dcb->active) |
257 | events &= ~EPOLLOUT; | |
258 | else | |
259 | dcb->active = EPOLLOUT; | |
9b495a58 ML |
260 | spin_unlock_irq(&dmabuf->poll.lock); |
261 | ||
6b51b02a | 262 | if (events & EPOLLOUT) { |
ff2d2384 MD |
263 | /* Paired with fput in dma_buf_poll_cb */ |
264 | get_file(dmabuf->file); | |
265 | ||
0a42016d | 266 | if (!dma_buf_poll_add_cb(resv, true, dcb)) |
6b51b02a | 267 | /* No callback queued, wake up any other waiters */ |
9b495a58 | 268 | dma_buf_poll_cb(NULL, &dcb->cb); |
6b51b02a CK |
269 | else |
270 | events &= ~EPOLLOUT; | |
9b495a58 ML |
271 | } |
272 | } | |
273 | ||
6b51b02a CK |
274 | if (events & EPOLLIN) { |
275 | struct dma_buf_poll_cb_t *dcb = &dmabuf->cb_in; | |
9b495a58 | 276 | |
6b51b02a | 277 | /* Check that callback isn't busy */ |
9b495a58 ML |
278 | spin_lock_irq(&dmabuf->poll.lock); |
279 | if (dcb->active) | |
6b51b02a | 280 | events &= ~EPOLLIN; |
9b495a58 | 281 | else |
6b51b02a | 282 | dcb->active = EPOLLIN; |
9b495a58 ML |
283 | spin_unlock_irq(&dmabuf->poll.lock); |
284 | ||
6b51b02a | 285 | if (events & EPOLLIN) { |
ff2d2384 MD |
286 | /* Paired with fput in dma_buf_poll_cb */ |
287 | get_file(dmabuf->file); | |
288 | ||
0a42016d | 289 | if (!dma_buf_poll_add_cb(resv, false, dcb)) |
6b51b02a | 290 | /* No callback queued, wake up any other waiters */ |
3c3b177a | 291 | dma_buf_poll_cb(NULL, &dcb->cb); |
6b51b02a CK |
292 | else |
293 | events &= ~EPOLLIN; | |
04a5faa8 | 294 | } |
9b495a58 ML |
295 | } |
296 | ||
6b51b02a | 297 | dma_resv_unlock(resv); |
9b495a58 ML |
298 | return events; |
299 | } | |
300 | ||
bb2bb903 GH |
301 | /** |
302 | * dma_buf_set_name - Set a name to a specific dma_buf to track the usage. | |
e73c317e GC |
303 | * It could support changing the name of the dma-buf if the same |
304 | * piece of memory is used for multiple purpose between different devices. | |
bb2bb903 | 305 | * |
6d3ba803 KK |
306 | * @dmabuf: [in] dmabuf buffer that will be renamed. |
307 | * @buf: [in] A piece of userspace memory that contains the name of | |
308 | * the dma-buf. | |
bb2bb903 GH |
309 | * |
310 | * Returns 0 on success. If the dma-buf buffer is already attached to | |
311 | * devices, return -EBUSY. | |
312 | * | |
313 | */ | |
314 | static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf) | |
315 | { | |
316 | char *name = strndup_user(buf, DMA_BUF_NAME_LEN); | |
bb2bb903 GH |
317 | |
318 | if (IS_ERR(name)) | |
319 | return PTR_ERR(name); | |
320 | ||
6348dd29 | 321 | spin_lock(&dmabuf->name_lock); |
bb2bb903 GH |
322 | kfree(dmabuf->name); |
323 | dmabuf->name = name; | |
6348dd29 | 324 | spin_unlock(&dmabuf->name_lock); |
bb2bb903 | 325 | |
e73c317e | 326 | return 0; |
bb2bb903 GH |
327 | } |
328 | ||
c11e391d DV |
329 | static long dma_buf_ioctl(struct file *file, |
330 | unsigned int cmd, unsigned long arg) | |
331 | { | |
332 | struct dma_buf *dmabuf; | |
333 | struct dma_buf_sync sync; | |
334 | enum dma_data_direction direction; | |
18b862dc | 335 | int ret; |
c11e391d DV |
336 | |
337 | dmabuf = file->private_data; | |
338 | ||
339 | switch (cmd) { | |
340 | case DMA_BUF_IOCTL_SYNC: | |
341 | if (copy_from_user(&sync, (void __user *) arg, sizeof(sync))) | |
342 | return -EFAULT; | |
343 | ||
344 | if (sync.flags & ~DMA_BUF_SYNC_VALID_FLAGS_MASK) | |
345 | return -EINVAL; | |
346 | ||
347 | switch (sync.flags & DMA_BUF_SYNC_RW) { | |
348 | case DMA_BUF_SYNC_READ: | |
349 | direction = DMA_FROM_DEVICE; | |
350 | break; | |
351 | case DMA_BUF_SYNC_WRITE: | |
352 | direction = DMA_TO_DEVICE; | |
353 | break; | |
354 | case DMA_BUF_SYNC_RW: | |
355 | direction = DMA_BIDIRECTIONAL; | |
356 | break; | |
357 | default: | |
358 | return -EINVAL; | |
359 | } | |
360 | ||
361 | if (sync.flags & DMA_BUF_SYNC_END) | |
18b862dc | 362 | ret = dma_buf_end_cpu_access(dmabuf, direction); |
c11e391d | 363 | else |
18b862dc | 364 | ret = dma_buf_begin_cpu_access(dmabuf, direction); |
c11e391d | 365 | |
18b862dc | 366 | return ret; |
bb2bb903 | 367 | |
a5bff92e DV |
368 | case DMA_BUF_SET_NAME_A: |
369 | case DMA_BUF_SET_NAME_B: | |
bb2bb903 GH |
370 | return dma_buf_set_name(dmabuf, (const char __user *)arg); |
371 | ||
c11e391d DV |
372 | default: |
373 | return -ENOTTY; | |
374 | } | |
375 | } | |
376 | ||
bcc07111 GH |
377 | static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file) |
378 | { | |
379 | struct dma_buf *dmabuf = file->private_data; | |
380 | ||
381 | seq_printf(m, "size:\t%zu\n", dmabuf->size); | |
382 | /* Don't count the temporary reference taken inside procfs seq_show */ | |
383 | seq_printf(m, "count:\t%ld\n", file_count(dmabuf->file) - 1); | |
384 | seq_printf(m, "exp_name:\t%s\n", dmabuf->exp_name); | |
6348dd29 | 385 | spin_lock(&dmabuf->name_lock); |
bcc07111 GH |
386 | if (dmabuf->name) |
387 | seq_printf(m, "name:\t%s\n", dmabuf->name); | |
6348dd29 | 388 | spin_unlock(&dmabuf->name_lock); |
bcc07111 GH |
389 | } |
390 | ||
d15bd7ee | 391 | static const struct file_operations dma_buf_fops = { |
05cd8469 | 392 | .release = dma_buf_file_release, |
4c78513e | 393 | .mmap = dma_buf_mmap_internal, |
19e8697b | 394 | .llseek = dma_buf_llseek, |
9b495a58 | 395 | .poll = dma_buf_poll, |
c11e391d | 396 | .unlocked_ioctl = dma_buf_ioctl, |
1832f2d8 | 397 | .compat_ioctl = compat_ptr_ioctl, |
bcc07111 | 398 | .show_fdinfo = dma_buf_show_fdinfo, |
d15bd7ee SS |
399 | }; |
400 | ||
401 | /* | |
402 | * is_dma_buf_file - Check if struct file* is associated with dma_buf | |
403 | */ | |
404 | static inline int is_dma_buf_file(struct file *file) | |
405 | { | |
406 | return file->f_op == &dma_buf_fops; | |
407 | } | |
408 | ||
ed63bb1d GH |
409 | static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags) |
410 | { | |
411 | struct file *file; | |
412 | struct inode *inode = alloc_anon_inode(dma_buf_mnt->mnt_sb); | |
413 | ||
414 | if (IS_ERR(inode)) | |
415 | return ERR_CAST(inode); | |
416 | ||
417 | inode->i_size = dmabuf->size; | |
418 | inode_set_bytes(inode, dmabuf->size); | |
419 | ||
420 | file = alloc_file_pseudo(inode, dma_buf_mnt, "dmabuf", | |
421 | flags, &dma_buf_fops); | |
422 | if (IS_ERR(file)) | |
423 | goto err_alloc_file; | |
424 | file->f_flags = flags & (O_ACCMODE | O_NONBLOCK); | |
425 | file->private_data = dmabuf; | |
bb2bb903 | 426 | file->f_path.dentry->d_fsdata = dmabuf; |
ed63bb1d GH |
427 | |
428 | return file; | |
429 | ||
430 | err_alloc_file: | |
431 | iput(inode); | |
432 | return file; | |
433 | } | |
434 | ||
2904a8c1 DV |
435 | /** |
436 | * DOC: dma buf device access | |
437 | * | |
438 | * For device DMA access to a shared DMA buffer the usual sequence of operations | |
439 | * is fairly simple: | |
440 | * | |
441 | * 1. The exporter defines his exporter instance using | |
442 | * DEFINE_DMA_BUF_EXPORT_INFO() and calls dma_buf_export() to wrap a private | |
443 | * buffer object into a &dma_buf. It then exports that &dma_buf to userspace | |
444 | * as a file descriptor by calling dma_buf_fd(). | |
445 | * | |
446 | * 2. Userspace passes this file-descriptors to all drivers it wants this buffer | |
d791aec9 | 447 | * to share with: First the file descriptor is converted to a &dma_buf using |
c138782d | 448 | * dma_buf_get(). Then the buffer is attached to the device using |
2904a8c1 DV |
449 | * dma_buf_attach(). |
450 | * | |
451 | * Up to this stage the exporter is still free to migrate or reallocate the | |
452 | * backing storage. | |
453 | * | |
c138782d | 454 | * 3. Once the buffer is attached to all devices userspace can initiate DMA |
2904a8c1 DV |
455 | * access to the shared buffer. In the kernel this is done by calling |
456 | * dma_buf_map_attachment() and dma_buf_unmap_attachment(). | |
457 | * | |
458 | * 4. Once a driver is done with a shared buffer it needs to call | |
459 | * dma_buf_detach() (after cleaning up any mappings) and then release the | |
85804b70 | 460 | * reference acquired with dma_buf_get() by calling dma_buf_put(). |
2904a8c1 DV |
461 | * |
462 | * For the detailed semantics exporters are expected to implement see | |
463 | * &dma_buf_ops. | |
464 | */ | |
465 | ||
d15bd7ee | 466 | /** |
d8fbe341 | 467 | * dma_buf_export - Creates a new dma_buf, and associates an anon file |
d15bd7ee SS |
468 | * with this buffer, so it can be exported. |
469 | * Also connect the allocator specific data and ops to the buffer. | |
78df9695 | 470 | * Additionally, provide a name string for exporter; useful in debugging. |
d15bd7ee | 471 | * |
d8fbe341 | 472 | * @exp_info: [in] holds all the export related information provided |
f641d3b5 | 473 | * by the exporter. see &struct dma_buf_export_info |
d8fbe341 | 474 | * for further details. |
d15bd7ee | 475 | * |
85804b70 DV |
476 | * Returns, on success, a newly created struct dma_buf object, which wraps the |
477 | * supplied private data and operations for struct dma_buf_ops. On either | |
478 | * missing ops, or error in allocating struct dma_buf, will return negative | |
479 | * error. | |
d15bd7ee | 480 | * |
2904a8c1 DV |
481 | * For most cases the easiest way to create @exp_info is through the |
482 | * %DEFINE_DMA_BUF_EXPORT_INFO macro. | |
d15bd7ee | 483 | */ |
d8fbe341 | 484 | struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) |
d15bd7ee SS |
485 | { |
486 | struct dma_buf *dmabuf; | |
52791eee | 487 | struct dma_resv *resv = exp_info->resv; |
d15bd7ee | 488 | struct file *file; |
3aac4502 | 489 | size_t alloc_size = sizeof(struct dma_buf); |
a026df4c | 490 | int ret; |
5136629d | 491 | |
d8fbe341 | 492 | if (!exp_info->resv) |
52791eee | 493 | alloc_size += sizeof(struct dma_resv); |
3aac4502 ML |
494 | else |
495 | /* prevent &dma_buf[1] == dma_buf->resv */ | |
496 | alloc_size += 1; | |
d15bd7ee | 497 | |
d8fbe341 SS |
498 | if (WARN_ON(!exp_info->priv |
499 | || !exp_info->ops | |
500 | || !exp_info->ops->map_dma_buf | |
501 | || !exp_info->ops->unmap_dma_buf | |
e3a9d6c5 | 502 | || !exp_info->ops->release)) { |
d15bd7ee SS |
503 | return ERR_PTR(-EINVAL); |
504 | } | |
505 | ||
15fd552d | 506 | if (WARN_ON(exp_info->ops->cache_sgt_mapping && |
bd2275ee | 507 | (exp_info->ops->pin || exp_info->ops->unpin))) |
15fd552d CK |
508 | return ERR_PTR(-EINVAL); |
509 | ||
bd2275ee | 510 | if (WARN_ON(!exp_info->ops->pin != !exp_info->ops->unpin)) |
15fd552d CK |
511 | return ERR_PTR(-EINVAL); |
512 | ||
9abdffe2 SS |
513 | if (!try_module_get(exp_info->owner)) |
514 | return ERR_PTR(-ENOENT); | |
515 | ||
3aac4502 | 516 | dmabuf = kzalloc(alloc_size, GFP_KERNEL); |
9abdffe2 | 517 | if (!dmabuf) { |
a026df4c CW |
518 | ret = -ENOMEM; |
519 | goto err_module; | |
9abdffe2 | 520 | } |
d15bd7ee | 521 | |
d8fbe341 SS |
522 | dmabuf->priv = exp_info->priv; |
523 | dmabuf->ops = exp_info->ops; | |
524 | dmabuf->size = exp_info->size; | |
525 | dmabuf->exp_name = exp_info->exp_name; | |
9abdffe2 | 526 | dmabuf->owner = exp_info->owner; |
6348dd29 | 527 | spin_lock_init(&dmabuf->name_lock); |
9b495a58 | 528 | init_waitqueue_head(&dmabuf->poll); |
6b51b02a CK |
529 | dmabuf->cb_in.poll = dmabuf->cb_out.poll = &dmabuf->poll; |
530 | dmabuf->cb_in.active = dmabuf->cb_out.active = 0; | |
9b495a58 | 531 | |
3aac4502 | 532 | if (!resv) { |
52791eee CK |
533 | resv = (struct dma_resv *)&dmabuf[1]; |
534 | dma_resv_init(resv); | |
3aac4502 ML |
535 | } |
536 | dmabuf->resv = resv; | |
d15bd7ee | 537 | |
ed63bb1d | 538 | file = dma_buf_getfile(dmabuf, exp_info->flags); |
9022e24e | 539 | if (IS_ERR(file)) { |
a026df4c CW |
540 | ret = PTR_ERR(file); |
541 | goto err_dmabuf; | |
9022e24e | 542 | } |
19e8697b CJHR |
543 | |
544 | file->f_mode |= FMODE_LSEEK; | |
d15bd7ee SS |
545 | dmabuf->file = file; |
546 | ||
bdb8d06d HV |
547 | ret = dma_buf_stats_setup(dmabuf); |
548 | if (ret) | |
549 | goto err_sysfs; | |
550 | ||
d15bd7ee SS |
551 | mutex_init(&dmabuf->lock); |
552 | INIT_LIST_HEAD(&dmabuf->attachments); | |
553 | ||
b89e3563 SS |
554 | mutex_lock(&db_list.lock); |
555 | list_add(&dmabuf->list_node, &db_list.head); | |
556 | mutex_unlock(&db_list.lock); | |
557 | ||
d15bd7ee | 558 | return dmabuf; |
a026df4c | 559 | |
bdb8d06d HV |
560 | err_sysfs: |
561 | /* | |
562 | * Set file->f_path.dentry->d_fsdata to NULL so that when | |
563 | * dma_buf_release() gets invoked by dentry_ops, it exits | |
564 | * early before calling the release() dma_buf op. | |
565 | */ | |
566 | file->f_path.dentry->d_fsdata = NULL; | |
567 | fput(file); | |
a026df4c CW |
568 | err_dmabuf: |
569 | kfree(dmabuf); | |
570 | err_module: | |
571 | module_put(exp_info->owner); | |
572 | return ERR_PTR(ret); | |
d15bd7ee | 573 | } |
16b0314a | 574 | EXPORT_SYMBOL_NS_GPL(dma_buf_export, DMA_BUF); |
d15bd7ee SS |
575 | |
576 | /** | |
85804b70 | 577 | * dma_buf_fd - returns a file descriptor for the given struct dma_buf |
d15bd7ee | 578 | * @dmabuf: [in] pointer to dma_buf for which fd is required. |
55c1c4ca | 579 | * @flags: [in] flags to give to fd |
d15bd7ee SS |
580 | * |
581 | * On success, returns an associated 'fd'. Else, returns error. | |
582 | */ | |
55c1c4ca | 583 | int dma_buf_fd(struct dma_buf *dmabuf, int flags) |
d15bd7ee | 584 | { |
f5e097f0 | 585 | int fd; |
d15bd7ee SS |
586 | |
587 | if (!dmabuf || !dmabuf->file) | |
588 | return -EINVAL; | |
589 | ||
f5e097f0 BP |
590 | fd = get_unused_fd_flags(flags); |
591 | if (fd < 0) | |
592 | return fd; | |
d15bd7ee SS |
593 | |
594 | fd_install(fd, dmabuf->file); | |
595 | ||
596 | return fd; | |
597 | } | |
16b0314a | 598 | EXPORT_SYMBOL_NS_GPL(dma_buf_fd, DMA_BUF); |
d15bd7ee SS |
599 | |
600 | /** | |
85804b70 DV |
601 | * dma_buf_get - returns the struct dma_buf related to an fd |
602 | * @fd: [in] fd associated with the struct dma_buf to be returned | |
d15bd7ee | 603 | * |
85804b70 | 604 | * On success, returns the struct dma_buf associated with an fd; uses |
d15bd7ee SS |
605 | * file's refcounting done by fget to increase refcount. returns ERR_PTR |
606 | * otherwise. | |
607 | */ | |
608 | struct dma_buf *dma_buf_get(int fd) | |
609 | { | |
610 | struct file *file; | |
611 | ||
612 | file = fget(fd); | |
613 | ||
614 | if (!file) | |
615 | return ERR_PTR(-EBADF); | |
616 | ||
617 | if (!is_dma_buf_file(file)) { | |
618 | fput(file); | |
619 | return ERR_PTR(-EINVAL); | |
620 | } | |
621 | ||
622 | return file->private_data; | |
623 | } | |
16b0314a | 624 | EXPORT_SYMBOL_NS_GPL(dma_buf_get, DMA_BUF); |
d15bd7ee SS |
625 | |
626 | /** | |
627 | * dma_buf_put - decreases refcount of the buffer | |
628 | * @dmabuf: [in] buffer to reduce refcount of | |
629 | * | |
2904a8c1 DV |
630 | * Uses file's refcounting done implicitly by fput(). |
631 | * | |
632 | * If, as a result of this call, the refcount becomes 0, the 'release' file | |
e9b4d7b5 DV |
633 | * operation related to this fd is called. It calls &dma_buf_ops.release vfunc |
634 | * in turn, and frees the memory allocated for dmabuf when exported. | |
d15bd7ee SS |
635 | */ |
636 | void dma_buf_put(struct dma_buf *dmabuf) | |
637 | { | |
638 | if (WARN_ON(!dmabuf || !dmabuf->file)) | |
639 | return; | |
640 | ||
641 | fput(dmabuf->file); | |
642 | } | |
16b0314a | 643 | EXPORT_SYMBOL_NS_GPL(dma_buf_put, DMA_BUF); |
d15bd7ee | 644 | |
84335675 DV |
645 | static void mangle_sg_table(struct sg_table *sg_table) |
646 | { | |
647 | #ifdef CONFIG_DMABUF_DEBUG | |
648 | int i; | |
649 | struct scatterlist *sg; | |
650 | ||
651 | /* To catch abuse of the underlying struct page by importers mix | |
652 | * up the bits, but take care to preserve the low SG_ bits to | |
653 | * not corrupt the sgt. The mixing is undone in __unmap_dma_buf | |
654 | * before passing the sgt back to the exporter. */ | |
655 | for_each_sgtable_sg(sg_table, sg, i) | |
656 | sg->page_link ^= ~0xffUL; | |
657 | #endif | |
658 | ||
659 | } | |
660 | static struct sg_table * __map_dma_buf(struct dma_buf_attachment *attach, | |
661 | enum dma_data_direction direction) | |
662 | { | |
663 | struct sg_table *sg_table; | |
664 | ||
665 | sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction); | |
666 | ||
667 | if (!IS_ERR_OR_NULL(sg_table)) | |
668 | mangle_sg_table(sg_table); | |
669 | ||
670 | return sg_table; | |
671 | } | |
672 | ||
d15bd7ee | 673 | /** |
85804b70 | 674 | * dma_buf_dynamic_attach - Add the device to dma_buf's attachments list |
15fd552d CK |
675 | * @dmabuf: [in] buffer to attach device to. |
676 | * @dev: [in] device to be attached. | |
6f49c251 RD |
677 | * @importer_ops: [in] importer operations for the attachment |
678 | * @importer_priv: [in] importer private pointer for the attachment | |
d15bd7ee | 679 | * |
2904a8c1 DV |
680 | * Returns struct dma_buf_attachment pointer for this attachment. Attachments |
681 | * must be cleaned up by calling dma_buf_detach(). | |
682 | * | |
85804b70 DV |
683 | * Optionally this calls &dma_buf_ops.attach to allow device-specific attach |
684 | * functionality. | |
685 | * | |
2904a8c1 DV |
686 | * Returns: |
687 | * | |
688 | * A pointer to newly created &dma_buf_attachment on success, or a negative | |
689 | * error code wrapped into a pointer on failure. | |
690 | * | |
691 | * Note that this can fail if the backing storage of @dmabuf is in a place not | |
692 | * accessible to @dev, and cannot be moved to a more suitable place. This is | |
693 | * indicated with the error code -EBUSY. | |
d15bd7ee | 694 | */ |
15fd552d CK |
695 | struct dma_buf_attachment * |
696 | dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, | |
bb42df46 CK |
697 | const struct dma_buf_attach_ops *importer_ops, |
698 | void *importer_priv) | |
d15bd7ee SS |
699 | { |
700 | struct dma_buf_attachment *attach; | |
701 | int ret; | |
702 | ||
d1aa06a1 | 703 | if (WARN_ON(!dmabuf || !dev)) |
d15bd7ee SS |
704 | return ERR_PTR(-EINVAL); |
705 | ||
4981cdb0 CK |
706 | if (WARN_ON(importer_ops && !importer_ops->move_notify)) |
707 | return ERR_PTR(-EINVAL); | |
708 | ||
db7942b6 | 709 | attach = kzalloc(sizeof(*attach), GFP_KERNEL); |
34d84ec4 | 710 | if (!attach) |
a9fbc3b7 | 711 | return ERR_PTR(-ENOMEM); |
d15bd7ee | 712 | |
d15bd7ee SS |
713 | attach->dev = dev; |
714 | attach->dmabuf = dmabuf; | |
09606b54 CK |
715 | if (importer_ops) |
716 | attach->peer2peer = importer_ops->allow_peer2peer; | |
bb42df46 CK |
717 | attach->importer_ops = importer_ops; |
718 | attach->importer_priv = importer_priv; | |
2ed9201b | 719 | |
d15bd7ee | 720 | if (dmabuf->ops->attach) { |
a19741e5 | 721 | ret = dmabuf->ops->attach(dmabuf, attach); |
d15bd7ee SS |
722 | if (ret) |
723 | goto err_attach; | |
724 | } | |
15fd552d | 725 | dma_resv_lock(dmabuf->resv, NULL); |
d15bd7ee | 726 | list_add(&attach->node, &dmabuf->attachments); |
15fd552d | 727 | dma_resv_unlock(dmabuf->resv); |
d15bd7ee | 728 | |
15fd552d CK |
729 | /* When either the importer or the exporter can't handle dynamic |
730 | * mappings we cache the mapping here to avoid issues with the | |
731 | * reservation object lock. | |
732 | */ | |
733 | if (dma_buf_attachment_is_dynamic(attach) != | |
734 | dma_buf_is_dynamic(dmabuf)) { | |
735 | struct sg_table *sgt; | |
736 | ||
bb42df46 | 737 | if (dma_buf_is_dynamic(attach->dmabuf)) { |
15fd552d | 738 | dma_resv_lock(attach->dmabuf->resv, NULL); |
7e008b02 | 739 | ret = dmabuf->ops->pin(attach); |
bb42df46 CK |
740 | if (ret) |
741 | goto err_unlock; | |
742 | } | |
15fd552d | 743 | |
84335675 | 744 | sgt = __map_dma_buf(attach, DMA_BIDIRECTIONAL); |
15fd552d CK |
745 | if (!sgt) |
746 | sgt = ERR_PTR(-ENOMEM); | |
747 | if (IS_ERR(sgt)) { | |
748 | ret = PTR_ERR(sgt); | |
bb42df46 | 749 | goto err_unpin; |
15fd552d CK |
750 | } |
751 | if (dma_buf_is_dynamic(attach->dmabuf)) | |
752 | dma_resv_unlock(attach->dmabuf->resv); | |
753 | attach->sgt = sgt; | |
754 | attach->dir = DMA_BIDIRECTIONAL; | |
755 | } | |
756 | ||
d15bd7ee SS |
757 | return attach; |
758 | ||
d15bd7ee SS |
759 | err_attach: |
760 | kfree(attach); | |
d15bd7ee | 761 | return ERR_PTR(ret); |
15fd552d | 762 | |
bb42df46 CK |
763 | err_unpin: |
764 | if (dma_buf_is_dynamic(attach->dmabuf)) | |
7e008b02 | 765 | dmabuf->ops->unpin(attach); |
bb42df46 | 766 | |
15fd552d CK |
767 | err_unlock: |
768 | if (dma_buf_is_dynamic(attach->dmabuf)) | |
769 | dma_resv_unlock(attach->dmabuf->resv); | |
770 | ||
771 | dma_buf_detach(dmabuf, attach); | |
772 | return ERR_PTR(ret); | |
773 | } | |
16b0314a | 774 | EXPORT_SYMBOL_NS_GPL(dma_buf_dynamic_attach, DMA_BUF); |
15fd552d CK |
775 | |
776 | /** | |
777 | * dma_buf_attach - Wrapper for dma_buf_dynamic_attach | |
778 | * @dmabuf: [in] buffer to attach device to. | |
779 | * @dev: [in] device to be attached. | |
780 | * | |
781 | * Wrapper to call dma_buf_dynamic_attach() for drivers which still use a static | |
782 | * mapping. | |
783 | */ | |
784 | struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, | |
785 | struct device *dev) | |
786 | { | |
bb42df46 | 787 | return dma_buf_dynamic_attach(dmabuf, dev, NULL, NULL); |
d15bd7ee | 788 | } |
16b0314a | 789 | EXPORT_SYMBOL_NS_GPL(dma_buf_attach, DMA_BUF); |
d15bd7ee | 790 | |
84335675 DV |
791 | static void __unmap_dma_buf(struct dma_buf_attachment *attach, |
792 | struct sg_table *sg_table, | |
793 | enum dma_data_direction direction) | |
794 | { | |
795 | /* uses XOR, hence this unmangles */ | |
796 | mangle_sg_table(sg_table); | |
797 | ||
798 | attach->dmabuf->ops->unmap_dma_buf(attach, sg_table, direction); | |
799 | } | |
800 | ||
d15bd7ee | 801 | /** |
85804b70 | 802 | * dma_buf_detach - Remove the given attachment from dmabuf's attachments list |
d15bd7ee SS |
803 | * @dmabuf: [in] buffer to detach from. |
804 | * @attach: [in] attachment to be detached; is free'd after this call. | |
805 | * | |
2904a8c1 | 806 | * Clean up a device attachment obtained by calling dma_buf_attach(). |
85804b70 DV |
807 | * |
808 | * Optionally this calls &dma_buf_ops.detach for device-specific detach. | |
d15bd7ee SS |
809 | */ |
810 | void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) | |
811 | { | |
d1aa06a1 | 812 | if (WARN_ON(!dmabuf || !attach)) |
d15bd7ee SS |
813 | return; |
814 | ||
15fd552d CK |
815 | if (attach->sgt) { |
816 | if (dma_buf_is_dynamic(attach->dmabuf)) | |
817 | dma_resv_lock(attach->dmabuf->resv, NULL); | |
818 | ||
84335675 | 819 | __unmap_dma_buf(attach, attach->sgt, attach->dir); |
f13e143e | 820 | |
bb42df46 | 821 | if (dma_buf_is_dynamic(attach->dmabuf)) { |
7e008b02 | 822 | dmabuf->ops->unpin(attach); |
15fd552d | 823 | dma_resv_unlock(attach->dmabuf->resv); |
bb42df46 | 824 | } |
15fd552d CK |
825 | } |
826 | ||
15fd552d | 827 | dma_resv_lock(dmabuf->resv, NULL); |
d15bd7ee | 828 | list_del(&attach->node); |
15fd552d | 829 | dma_resv_unlock(dmabuf->resv); |
d15bd7ee SS |
830 | if (dmabuf->ops->detach) |
831 | dmabuf->ops->detach(dmabuf, attach); | |
832 | ||
d15bd7ee SS |
833 | kfree(attach); |
834 | } | |
16b0314a | 835 | EXPORT_SYMBOL_NS_GPL(dma_buf_detach, DMA_BUF); |
d15bd7ee | 836 | |
bb42df46 CK |
837 | /** |
838 | * dma_buf_pin - Lock down the DMA-buf | |
bb42df46 CK |
839 | * @attach: [in] attachment which should be pinned |
840 | * | |
c545781e DV |
841 | * Only dynamic importers (who set up @attach with dma_buf_dynamic_attach()) may |
842 | * call this, and only for limited use cases like scanout and not for temporary | |
843 | * pin operations. It is not permitted to allow userspace to pin arbitrary | |
844 | * amounts of buffers through this interface. | |
845 | * | |
846 | * Buffers must be unpinned by calling dma_buf_unpin(). | |
847 | * | |
bb42df46 CK |
848 | * Returns: |
849 | * 0 on success, negative error code on failure. | |
850 | */ | |
851 | int dma_buf_pin(struct dma_buf_attachment *attach) | |
852 | { | |
853 | struct dma_buf *dmabuf = attach->dmabuf; | |
854 | int ret = 0; | |
855 | ||
c545781e DV |
856 | WARN_ON(!dma_buf_attachment_is_dynamic(attach)); |
857 | ||
bb42df46 CK |
858 | dma_resv_assert_held(dmabuf->resv); |
859 | ||
860 | if (dmabuf->ops->pin) | |
861 | ret = dmabuf->ops->pin(attach); | |
862 | ||
863 | return ret; | |
864 | } | |
16b0314a | 865 | EXPORT_SYMBOL_NS_GPL(dma_buf_pin, DMA_BUF); |
bb42df46 CK |
866 | |
867 | /** | |
c545781e | 868 | * dma_buf_unpin - Unpin a DMA-buf |
bb42df46 | 869 | * @attach: [in] attachment which should be unpinned |
c545781e DV |
870 | * |
871 | * This unpins a buffer pinned by dma_buf_pin() and allows the exporter to move | |
872 | * any mapping of @attach again and inform the importer through | |
873 | * &dma_buf_attach_ops.move_notify. | |
bb42df46 CK |
874 | */ |
875 | void dma_buf_unpin(struct dma_buf_attachment *attach) | |
876 | { | |
877 | struct dma_buf *dmabuf = attach->dmabuf; | |
878 | ||
c545781e DV |
879 | WARN_ON(!dma_buf_attachment_is_dynamic(attach)); |
880 | ||
bb42df46 CK |
881 | dma_resv_assert_held(dmabuf->resv); |
882 | ||
883 | if (dmabuf->ops->unpin) | |
884 | dmabuf->ops->unpin(attach); | |
885 | } | |
16b0314a | 886 | EXPORT_SYMBOL_NS_GPL(dma_buf_unpin, DMA_BUF); |
bb42df46 | 887 | |
d15bd7ee SS |
888 | /** |
889 | * dma_buf_map_attachment - Returns the scatterlist table of the attachment; | |
890 | * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the | |
891 | * dma_buf_ops. | |
892 | * @attach: [in] attachment whose scatterlist is to be returned | |
893 | * @direction: [in] direction of DMA transfer | |
894 | * | |
fee0c54e | 895 | * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR |
2904a8c1 DV |
896 | * on error. May return -EINTR if it is interrupted by a signal. |
897 | * | |
ac80cd17 JX |
898 | * On success, the DMA addresses and lengths in the returned scatterlist are |
899 | * PAGE_SIZE aligned. | |
900 | * | |
c138782d | 901 | * A mapping must be unmapped by using dma_buf_unmap_attachment(). Note that |
2904a8c1 DV |
902 | * the underlying backing storage is pinned for as long as a mapping exists, |
903 | * therefore users/importers should not hold onto a mapping for undue amounts of | |
904 | * time. | |
89bcadc8 DV |
905 | * |
906 | * Important: Dynamic importers must wait for the exclusive fence of the struct | |
907 | * dma_resv attached to the DMA-BUF first. | |
d15bd7ee SS |
908 | */ |
909 | struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, | |
910 | enum dma_data_direction direction) | |
911 | { | |
531beb06 | 912 | struct sg_table *sg_table; |
bb42df46 | 913 | int r; |
d15bd7ee SS |
914 | |
915 | might_sleep(); | |
916 | ||
d1aa06a1 | 917 | if (WARN_ON(!attach || !attach->dmabuf)) |
d15bd7ee SS |
918 | return ERR_PTR(-EINVAL); |
919 | ||
15fd552d CK |
920 | if (dma_buf_attachment_is_dynamic(attach)) |
921 | dma_resv_assert_held(attach->dmabuf->resv); | |
922 | ||
f13e143e CK |
923 | if (attach->sgt) { |
924 | /* | |
925 | * Two mappings with different directions for the same | |
926 | * attachment are not allowed. | |
927 | */ | |
928 | if (attach->dir != direction && | |
929 | attach->dir != DMA_BIDIRECTIONAL) | |
930 | return ERR_PTR(-EBUSY); | |
931 | ||
932 | return attach->sgt; | |
933 | } | |
934 | ||
bb42df46 | 935 | if (dma_buf_is_dynamic(attach->dmabuf)) { |
15fd552d | 936 | dma_resv_assert_held(attach->dmabuf->resv); |
4981cdb0 | 937 | if (!IS_ENABLED(CONFIG_DMABUF_MOVE_NOTIFY)) { |
7e008b02 | 938 | r = attach->dmabuf->ops->pin(attach); |
bb42df46 CK |
939 | if (r) |
940 | return ERR_PTR(r); | |
941 | } | |
942 | } | |
15fd552d | 943 | |
84335675 | 944 | sg_table = __map_dma_buf(attach, direction); |
fee0c54e CC |
945 | if (!sg_table) |
946 | sg_table = ERR_PTR(-ENOMEM); | |
d15bd7ee | 947 | |
bb42df46 | 948 | if (IS_ERR(sg_table) && dma_buf_is_dynamic(attach->dmabuf) && |
4981cdb0 | 949 | !IS_ENABLED(CONFIG_DMABUF_MOVE_NOTIFY)) |
7e008b02 | 950 | attach->dmabuf->ops->unpin(attach); |
bb42df46 | 951 | |
f13e143e CK |
952 | if (!IS_ERR(sg_table) && attach->dmabuf->ops->cache_sgt_mapping) { |
953 | attach->sgt = sg_table; | |
954 | attach->dir = direction; | |
955 | } | |
956 | ||
ac80cd17 | 957 | #ifdef CONFIG_DMA_API_DEBUG |
00efd65a | 958 | if (!IS_ERR(sg_table)) { |
ac80cd17 JX |
959 | struct scatterlist *sg; |
960 | u64 addr; | |
961 | int len; | |
962 | int i; | |
963 | ||
964 | for_each_sgtable_dma_sg(sg_table, sg, i) { | |
965 | addr = sg_dma_address(sg); | |
966 | len = sg_dma_len(sg); | |
967 | if (!PAGE_ALIGNED(addr) || !PAGE_ALIGNED(len)) { | |
968 | pr_debug("%s: addr %llx or len %x is not page aligned!\n", | |
969 | __func__, addr, len); | |
970 | } | |
971 | } | |
972 | } | |
973 | #endif /* CONFIG_DMA_API_DEBUG */ | |
d15bd7ee SS |
974 | return sg_table; |
975 | } | |
16b0314a | 976 | EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment, DMA_BUF); |
d15bd7ee SS |
977 | |
978 | /** | |
979 | * dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might | |
980 | * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of | |
981 | * dma_buf_ops. | |
982 | * @attach: [in] attachment to unmap buffer from | |
983 | * @sg_table: [in] scatterlist info of the buffer to unmap | |
33ea2dcb | 984 | * @direction: [in] direction of DMA transfer |
d15bd7ee | 985 | * |
2904a8c1 | 986 | * This unmaps a DMA mapping for @attached obtained by dma_buf_map_attachment(). |
d15bd7ee SS |
987 | */ |
988 | void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, | |
33ea2dcb SS |
989 | struct sg_table *sg_table, |
990 | enum dma_data_direction direction) | |
d15bd7ee | 991 | { |
b6fa0cd6 RC |
992 | might_sleep(); |
993 | ||
d1aa06a1 | 994 | if (WARN_ON(!attach || !attach->dmabuf || !sg_table)) |
d15bd7ee SS |
995 | return; |
996 | ||
15fd552d CK |
997 | if (dma_buf_attachment_is_dynamic(attach)) |
998 | dma_resv_assert_held(attach->dmabuf->resv); | |
999 | ||
f13e143e CK |
1000 | if (attach->sgt == sg_table) |
1001 | return; | |
1002 | ||
15fd552d CK |
1003 | if (dma_buf_is_dynamic(attach->dmabuf)) |
1004 | dma_resv_assert_held(attach->dmabuf->resv); | |
1005 | ||
84335675 | 1006 | __unmap_dma_buf(attach, sg_table, direction); |
bb42df46 CK |
1007 | |
1008 | if (dma_buf_is_dynamic(attach->dmabuf) && | |
4981cdb0 | 1009 | !IS_ENABLED(CONFIG_DMABUF_MOVE_NOTIFY)) |
bb42df46 | 1010 | dma_buf_unpin(attach); |
d15bd7ee | 1011 | } |
16b0314a | 1012 | EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment, DMA_BUF); |
fc13020e | 1013 | |
bb42df46 CK |
1014 | /** |
1015 | * dma_buf_move_notify - notify attachments that DMA-buf is moving | |
1016 | * | |
1017 | * @dmabuf: [in] buffer which is moving | |
1018 | * | |
1019 | * Informs all attachmenst that they need to destroy and recreated all their | |
1020 | * mappings. | |
1021 | */ | |
1022 | void dma_buf_move_notify(struct dma_buf *dmabuf) | |
1023 | { | |
1024 | struct dma_buf_attachment *attach; | |
1025 | ||
1026 | dma_resv_assert_held(dmabuf->resv); | |
1027 | ||
1028 | list_for_each_entry(attach, &dmabuf->attachments, node) | |
4981cdb0 | 1029 | if (attach->importer_ops) |
bb42df46 CK |
1030 | attach->importer_ops->move_notify(attach); |
1031 | } | |
16b0314a | 1032 | EXPORT_SYMBOL_NS_GPL(dma_buf_move_notify, DMA_BUF); |
bb42df46 | 1033 | |
0959a168 DV |
1034 | /** |
1035 | * DOC: cpu access | |
1036 | * | |
1037 | * There are mutliple reasons for supporting CPU access to a dma buffer object: | |
1038 | * | |
1039 | * - Fallback operations in the kernel, for example when a device is connected | |
1040 | * over USB and the kernel needs to shuffle the data around first before | |
1041 | * sending it away. Cache coherency is handled by braketing any transactions | |
1042 | * with calls to dma_buf_begin_cpu_access() and dma_buf_end_cpu_access() | |
1043 | * access. | |
1044 | * | |
7f0de8d8 DV |
1045 | * Since for most kernel internal dma-buf accesses need the entire buffer, a |
1046 | * vmap interface is introduced. Note that on very old 32-bit architectures | |
1047 | * vmalloc space might be limited and result in vmap calls failing. | |
0959a168 DV |
1048 | * |
1049 | * Interfaces:: | |
de9114ec | 1050 | * |
7938f421 LDM |
1051 | * void \*dma_buf_vmap(struct dma_buf \*dmabuf, struct iosys_map \*map) |
1052 | * void dma_buf_vunmap(struct dma_buf \*dmabuf, struct iosys_map \*map) | |
0959a168 DV |
1053 | * |
1054 | * The vmap call can fail if there is no vmap support in the exporter, or if | |
de9114ec DV |
1055 | * it runs out of vmalloc space. Note that the dma-buf layer keeps a reference |
1056 | * count for all vmap access and calls down into the exporter's vmap function | |
1057 | * only when no vmapping exists, and only unmaps it once. Protection against | |
1058 | * concurrent vmap/vunmap calls is provided by taking the &dma_buf.lock mutex. | |
0959a168 DV |
1059 | * |
1060 | * - For full compatibility on the importer side with existing userspace | |
1061 | * interfaces, which might already support mmap'ing buffers. This is needed in | |
1062 | * many processing pipelines (e.g. feeding a software rendered image into a | |
1063 | * hardware pipeline, thumbnail creation, snapshots, ...). Also, Android's ION | |
1064 | * framework already supported this and for DMA buffer file descriptors to | |
1065 | * replace ION buffers mmap support was needed. | |
1066 | * | |
1067 | * There is no special interfaces, userspace simply calls mmap on the dma-buf | |
1068 | * fd. But like for CPU access there's a need to braket the actual access, | |
1069 | * which is handled by the ioctl (DMA_BUF_IOCTL_SYNC). Note that | |
1070 | * DMA_BUF_IOCTL_SYNC can fail with -EAGAIN or -EINTR, in which case it must | |
1071 | * be restarted. | |
1072 | * | |
1073 | * Some systems might need some sort of cache coherency management e.g. when | |
1074 | * CPU and GPU domains are being accessed through dma-buf at the same time. | |
1075 | * To circumvent this problem there are begin/end coherency markers, that | |
1076 | * forward directly to existing dma-buf device drivers vfunc hooks. Userspace | |
1077 | * can make use of those markers through the DMA_BUF_IOCTL_SYNC ioctl. The | |
1078 | * sequence would be used like following: | |
1079 | * | |
1080 | * - mmap dma-buf fd | |
1081 | * - for each drawing/upload cycle in CPU 1. SYNC_START ioctl, 2. read/write | |
1082 | * to mmap area 3. SYNC_END ioctl. This can be repeated as often as you | |
1083 | * want (with the new data being consumed by say the GPU or the scanout | |
1084 | * device) | |
1085 | * - munmap once you don't need the buffer any more | |
1086 | * | |
1087 | * For correctness and optimal performance, it is always required to use | |
1088 | * SYNC_START and SYNC_END before and after, respectively, when accessing the | |
1089 | * mapped address. Userspace cannot rely on coherent access, even when there | |
1090 | * are systems where it just works without calling these ioctls. | |
1091 | * | |
1092 | * - And as a CPU fallback in userspace processing pipelines. | |
1093 | * | |
1094 | * Similar to the motivation for kernel cpu access it is again important that | |
1095 | * the userspace code of a given importing subsystem can use the same | |
1096 | * interfaces with a imported dma-buf buffer object as with a native buffer | |
1097 | * object. This is especially important for drm where the userspace part of | |
1098 | * contemporary OpenGL, X, and other drivers is huge, and reworking them to | |
1099 | * use a different way to mmap a buffer rather invasive. | |
1100 | * | |
1101 | * The assumption in the current dma-buf interfaces is that redirecting the | |
1102 | * initial mmap is all that's needed. A survey of some of the existing | |
1103 | * subsystems shows that no driver seems to do any nefarious thing like | |
1104 | * syncing up with outstanding asynchronous processing on the device or | |
1105 | * allocating special resources at fault time. So hopefully this is good | |
1106 | * enough, since adding interfaces to intercept pagefaults and allow pte | |
1107 | * shootdowns would increase the complexity quite a bit. | |
1108 | * | |
1109 | * Interface:: | |
85804b70 | 1110 | * |
0959a168 DV |
1111 | * int dma_buf_mmap(struct dma_buf \*, struct vm_area_struct \*, |
1112 | * unsigned long); | |
1113 | * | |
1114 | * If the importing subsystem simply provides a special-purpose mmap call to | |
85804b70 | 1115 | * set up a mapping in userspace, calling do_mmap with &dma_buf.file will |
0959a168 DV |
1116 | * equally achieve that for a dma-buf object. |
1117 | */ | |
1118 | ||
ae4e46b1 CW |
1119 | static int __dma_buf_begin_cpu_access(struct dma_buf *dmabuf, |
1120 | enum dma_data_direction direction) | |
1121 | { | |
1122 | bool write = (direction == DMA_BIDIRECTIONAL || | |
1123 | direction == DMA_TO_DEVICE); | |
52791eee | 1124 | struct dma_resv *resv = dmabuf->resv; |
ae4e46b1 CW |
1125 | long ret; |
1126 | ||
1127 | /* Wait on any implicit rendering fences */ | |
7bc80a54 CK |
1128 | ret = dma_resv_wait_timeout(resv, dma_resv_usage_rw(write), |
1129 | true, MAX_SCHEDULE_TIMEOUT); | |
ae4e46b1 CW |
1130 | if (ret < 0) |
1131 | return ret; | |
1132 | ||
1133 | return 0; | |
1134 | } | |
fc13020e DV |
1135 | |
1136 | /** | |
1137 | * dma_buf_begin_cpu_access - Must be called before accessing a dma_buf from the | |
1138 | * cpu in the kernel context. Calls begin_cpu_access to allow exporter-specific | |
1139 | * preparations. Coherency is only guaranteed in the specified range for the | |
1140 | * specified access direction. | |
efb4df82 | 1141 | * @dmabuf: [in] buffer to prepare cpu access for. |
fc13020e DV |
1142 | * @direction: [in] length of range for cpu access. |
1143 | * | |
0959a168 DV |
1144 | * After the cpu access is complete the caller should call |
1145 | * dma_buf_end_cpu_access(). Only when cpu access is braketed by both calls is | |
1146 | * it guaranteed to be coherent with other DMA access. | |
1147 | * | |
de9114ec DV |
1148 | * This function will also wait for any DMA transactions tracked through |
1149 | * implicit synchronization in &dma_buf.resv. For DMA transactions with explicit | |
1150 | * synchronization this function will only ensure cache coherency, callers must | |
1151 | * ensure synchronization with such DMA transactions on their own. | |
1152 | * | |
fc13020e DV |
1153 | * Can return negative error values, returns 0 on success. |
1154 | */ | |
831e9da7 | 1155 | int dma_buf_begin_cpu_access(struct dma_buf *dmabuf, |
fc13020e DV |
1156 | enum dma_data_direction direction) |
1157 | { | |
1158 | int ret = 0; | |
1159 | ||
1160 | if (WARN_ON(!dmabuf)) | |
1161 | return -EINVAL; | |
1162 | ||
8ccf0a29 DV |
1163 | might_lock(&dmabuf->resv->lock.base); |
1164 | ||
fc13020e | 1165 | if (dmabuf->ops->begin_cpu_access) |
831e9da7 | 1166 | ret = dmabuf->ops->begin_cpu_access(dmabuf, direction); |
fc13020e | 1167 | |
ae4e46b1 CW |
1168 | /* Ensure that all fences are waited upon - but we first allow |
1169 | * the native handler the chance to do so more efficiently if it | |
1170 | * chooses. A double invocation here will be reasonably cheap no-op. | |
1171 | */ | |
1172 | if (ret == 0) | |
1173 | ret = __dma_buf_begin_cpu_access(dmabuf, direction); | |
1174 | ||
fc13020e DV |
1175 | return ret; |
1176 | } | |
16b0314a | 1177 | EXPORT_SYMBOL_NS_GPL(dma_buf_begin_cpu_access, DMA_BUF); |
fc13020e DV |
1178 | |
1179 | /** | |
1180 | * dma_buf_end_cpu_access - Must be called after accessing a dma_buf from the | |
1181 | * cpu in the kernel context. Calls end_cpu_access to allow exporter-specific | |
1182 | * actions. Coherency is only guaranteed in the specified range for the | |
1183 | * specified access direction. | |
efb4df82 | 1184 | * @dmabuf: [in] buffer to complete cpu access for. |
fc13020e DV |
1185 | * @direction: [in] length of range for cpu access. |
1186 | * | |
0959a168 DV |
1187 | * This terminates CPU access started with dma_buf_begin_cpu_access(). |
1188 | * | |
87e332d5 | 1189 | * Can return negative error values, returns 0 on success. |
fc13020e | 1190 | */ |
18b862dc CW |
1191 | int dma_buf_end_cpu_access(struct dma_buf *dmabuf, |
1192 | enum dma_data_direction direction) | |
fc13020e | 1193 | { |
18b862dc CW |
1194 | int ret = 0; |
1195 | ||
fc13020e DV |
1196 | WARN_ON(!dmabuf); |
1197 | ||
8ccf0a29 DV |
1198 | might_lock(&dmabuf->resv->lock.base); |
1199 | ||
fc13020e | 1200 | if (dmabuf->ops->end_cpu_access) |
18b862dc CW |
1201 | ret = dmabuf->ops->end_cpu_access(dmabuf, direction); |
1202 | ||
1203 | return ret; | |
fc13020e | 1204 | } |
16b0314a | 1205 | EXPORT_SYMBOL_NS_GPL(dma_buf_end_cpu_access, DMA_BUF); |
fc13020e | 1206 | |
4c78513e DV |
1207 | |
1208 | /** | |
1209 | * dma_buf_mmap - Setup up a userspace mmap with the given vma | |
12c4727e | 1210 | * @dmabuf: [in] buffer that should back the vma |
4c78513e DV |
1211 | * @vma: [in] vma for the mmap |
1212 | * @pgoff: [in] offset in pages where this mmap should start within the | |
5136629d | 1213 | * dma-buf buffer. |
4c78513e DV |
1214 | * |
1215 | * This function adjusts the passed in vma so that it points at the file of the | |
ecf1dbac | 1216 | * dma_buf operation. It also adjusts the starting pgoff and does bounds |
4c78513e DV |
1217 | * checking on the size of the vma. Then it calls the exporters mmap function to |
1218 | * set up the mapping. | |
1219 | * | |
1220 | * Can return negative error values, returns 0 on success. | |
1221 | */ | |
1222 | int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, | |
1223 | unsigned long pgoff) | |
1224 | { | |
1225 | if (WARN_ON(!dmabuf || !vma)) | |
1226 | return -EINVAL; | |
1227 | ||
e3a9d6c5 AD |
1228 | /* check if buffer supports mmap */ |
1229 | if (!dmabuf->ops->mmap) | |
1230 | return -EINVAL; | |
1231 | ||
4c78513e | 1232 | /* check for offset overflow */ |
b02da6f8 | 1233 | if (pgoff + vma_pages(vma) < pgoff) |
4c78513e DV |
1234 | return -EOVERFLOW; |
1235 | ||
1236 | /* check for overflowing the buffer's size */ | |
b02da6f8 | 1237 | if (pgoff + vma_pages(vma) > |
4c78513e DV |
1238 | dmabuf->size >> PAGE_SHIFT) |
1239 | return -EINVAL; | |
1240 | ||
1241 | /* readjust the vma */ | |
295992fb | 1242 | vma_set_file(vma, dmabuf->file); |
4c78513e DV |
1243 | vma->vm_pgoff = pgoff; |
1244 | ||
1527f926 | 1245 | return dmabuf->ops->mmap(dmabuf, vma); |
4c78513e | 1246 | } |
16b0314a | 1247 | EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF); |
98f86c9e DA |
1248 | |
1249 | /** | |
12c4727e SS |
1250 | * dma_buf_vmap - Create virtual mapping for the buffer object into kernel |
1251 | * address space. Same restrictions as for vmap and friends apply. | |
1252 | * @dmabuf: [in] buffer to vmap | |
6619ccf1 | 1253 | * @map: [out] returns the vmap pointer |
98f86c9e DA |
1254 | * |
1255 | * This call may fail due to lack of virtual mapping address space. | |
1256 | * These calls are optional in drivers. The intended use for them | |
1257 | * is for mapping objects linear in kernel space for high use objects. | |
de9114ec DV |
1258 | * |
1259 | * To ensure coherency users must call dma_buf_begin_cpu_access() and | |
1260 | * dma_buf_end_cpu_access() around any cpu access performed through this | |
1261 | * mapping. | |
fee0c54e | 1262 | * |
6619ccf1 | 1263 | * Returns 0 on success, or a negative errno code otherwise. |
98f86c9e | 1264 | */ |
7938f421 | 1265 | int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map) |
98f86c9e | 1266 | { |
7938f421 | 1267 | struct iosys_map ptr; |
6619ccf1 TZ |
1268 | int ret = 0; |
1269 | ||
7938f421 | 1270 | iosys_map_clear(map); |
f00b4dad | 1271 | |
98f86c9e | 1272 | if (WARN_ON(!dmabuf)) |
6619ccf1 | 1273 | return -EINVAL; |
98f86c9e | 1274 | |
f00b4dad | 1275 | if (!dmabuf->ops->vmap) |
6619ccf1 | 1276 | return -EINVAL; |
f00b4dad DV |
1277 | |
1278 | mutex_lock(&dmabuf->lock); | |
1279 | if (dmabuf->vmapping_counter) { | |
1280 | dmabuf->vmapping_counter++; | |
7938f421 | 1281 | BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr)); |
6619ccf1 | 1282 | *map = dmabuf->vmap_ptr; |
f00b4dad DV |
1283 | goto out_unlock; |
1284 | } | |
1285 | ||
7938f421 | 1286 | BUG_ON(iosys_map_is_set(&dmabuf->vmap_ptr)); |
f00b4dad | 1287 | |
6619ccf1 TZ |
1288 | ret = dmabuf->ops->vmap(dmabuf, &ptr); |
1289 | if (WARN_ON_ONCE(ret)) | |
f00b4dad DV |
1290 | goto out_unlock; |
1291 | ||
6619ccf1 | 1292 | dmabuf->vmap_ptr = ptr; |
f00b4dad DV |
1293 | dmabuf->vmapping_counter = 1; |
1294 | ||
6619ccf1 TZ |
1295 | *map = dmabuf->vmap_ptr; |
1296 | ||
f00b4dad DV |
1297 | out_unlock: |
1298 | mutex_unlock(&dmabuf->lock); | |
6619ccf1 | 1299 | return ret; |
98f86c9e | 1300 | } |
16b0314a | 1301 | EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF); |
98f86c9e DA |
1302 | |
1303 | /** | |
1304 | * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap. | |
12c4727e | 1305 | * @dmabuf: [in] buffer to vunmap |
20e76f1a | 1306 | * @map: [in] vmap pointer to vunmap |
98f86c9e | 1307 | */ |
7938f421 | 1308 | void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) |
98f86c9e DA |
1309 | { |
1310 | if (WARN_ON(!dmabuf)) | |
1311 | return; | |
1312 | ||
7938f421 | 1313 | BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr)); |
f00b4dad | 1314 | BUG_ON(dmabuf->vmapping_counter == 0); |
7938f421 | 1315 | BUG_ON(!iosys_map_is_equal(&dmabuf->vmap_ptr, map)); |
f00b4dad DV |
1316 | |
1317 | mutex_lock(&dmabuf->lock); | |
1318 | if (--dmabuf->vmapping_counter == 0) { | |
1319 | if (dmabuf->ops->vunmap) | |
20e76f1a | 1320 | dmabuf->ops->vunmap(dmabuf, map); |
7938f421 | 1321 | iosys_map_clear(&dmabuf->vmap_ptr); |
f00b4dad DV |
1322 | } |
1323 | mutex_unlock(&dmabuf->lock); | |
98f86c9e | 1324 | } |
16b0314a | 1325 | EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF); |
b89e3563 SS |
1326 | |
1327 | #ifdef CONFIG_DEBUG_FS | |
eb0b947e | 1328 | static int dma_buf_debug_show(struct seq_file *s, void *unused) |
b89e3563 | 1329 | { |
b89e3563 SS |
1330 | struct dma_buf *buf_obj; |
1331 | struct dma_buf_attachment *attach_obj; | |
63639d01 | 1332 | int count = 0, attach_count; |
b89e3563 | 1333 | size_t size = 0; |
680753dd | 1334 | int ret; |
b89e3563 SS |
1335 | |
1336 | ret = mutex_lock_interruptible(&db_list.lock); | |
1337 | ||
1338 | if (ret) | |
1339 | return ret; | |
1340 | ||
c0b00a52 | 1341 | seq_puts(s, "\nDma-buf Objects:\n"); |
ed63bb1d GH |
1342 | seq_printf(s, "%-8s\t%-8s\t%-8s\t%-8s\texp_name\t%-8s\n", |
1343 | "size", "flags", "mode", "count", "ino"); | |
b89e3563 SS |
1344 | |
1345 | list_for_each_entry(buf_obj, &db_list.head, list_node) { | |
15fd552d | 1346 | |
15fd552d CK |
1347 | ret = dma_resv_lock_interruptible(buf_obj->resv, NULL); |
1348 | if (ret) | |
f45f57cc | 1349 | goto error_unlock; |
b89e3563 | 1350 | |
8c0fd126 GC |
1351 | |
1352 | spin_lock(&buf_obj->name_lock); | |
bb2bb903 | 1353 | seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\t%s\n", |
c0b00a52 | 1354 | buf_obj->size, |
b89e3563 | 1355 | buf_obj->file->f_flags, buf_obj->file->f_mode, |
a1f6dbac | 1356 | file_count(buf_obj->file), |
ed63bb1d | 1357 | buf_obj->exp_name, |
bb2bb903 GH |
1358 | file_inode(buf_obj->file)->i_ino, |
1359 | buf_obj->name ?: ""); | |
8c0fd126 | 1360 | spin_unlock(&buf_obj->name_lock); |
b89e3563 | 1361 | |
a25efb38 | 1362 | dma_resv_describe(buf_obj->resv, s); |
5eb2c72c | 1363 | |
c0b00a52 | 1364 | seq_puts(s, "\tAttached Devices:\n"); |
b89e3563 SS |
1365 | attach_count = 0; |
1366 | ||
1367 | list_for_each_entry(attach_obj, &buf_obj->attachments, node) { | |
9eddb41d | 1368 | seq_printf(s, "\t%s\n", dev_name(attach_obj->dev)); |
b89e3563 SS |
1369 | attach_count++; |
1370 | } | |
15fd552d | 1371 | dma_resv_unlock(buf_obj->resv); |
b89e3563 | 1372 | |
c0b00a52 | 1373 | seq_printf(s, "Total %d devices attached\n\n", |
b89e3563 SS |
1374 | attach_count); |
1375 | ||
1376 | count++; | |
1377 | size += buf_obj->size; | |
b89e3563 SS |
1378 | } |
1379 | ||
1380 | seq_printf(s, "\nTotal %d objects, %zu bytes\n", count, size); | |
1381 | ||
1382 | mutex_unlock(&db_list.lock); | |
1383 | return 0; | |
15fd552d | 1384 | |
f45f57cc | 1385 | error_unlock: |
15fd552d CK |
1386 | mutex_unlock(&db_list.lock); |
1387 | return ret; | |
b89e3563 SS |
1388 | } |
1389 | ||
2674305a | 1390 | DEFINE_SHOW_ATTRIBUTE(dma_buf_debug); |
b89e3563 SS |
1391 | |
1392 | static struct dentry *dma_buf_debugfs_dir; | |
1393 | ||
1394 | static int dma_buf_init_debugfs(void) | |
1395 | { | |
bd3e2208 | 1396 | struct dentry *d; |
b89e3563 | 1397 | int err = 0; |
5136629d | 1398 | |
bd3e2208 MK |
1399 | d = debugfs_create_dir("dma_buf", NULL); |
1400 | if (IS_ERR(d)) | |
1401 | return PTR_ERR(d); | |
5136629d | 1402 | |
bd3e2208 | 1403 | dma_buf_debugfs_dir = d; |
b89e3563 | 1404 | |
bd3e2208 MK |
1405 | d = debugfs_create_file("bufinfo", S_IRUGO, dma_buf_debugfs_dir, |
1406 | NULL, &dma_buf_debug_fops); | |
1407 | if (IS_ERR(d)) { | |
b89e3563 | 1408 | pr_debug("dma_buf: debugfs: failed to create node bufinfo\n"); |
b7479990 MK |
1409 | debugfs_remove_recursive(dma_buf_debugfs_dir); |
1410 | dma_buf_debugfs_dir = NULL; | |
bd3e2208 | 1411 | err = PTR_ERR(d); |
b7479990 | 1412 | } |
b89e3563 SS |
1413 | |
1414 | return err; | |
1415 | } | |
1416 | ||
1417 | static void dma_buf_uninit_debugfs(void) | |
1418 | { | |
298b6a81 | 1419 | debugfs_remove_recursive(dma_buf_debugfs_dir); |
b89e3563 | 1420 | } |
b89e3563 SS |
1421 | #else |
1422 | static inline int dma_buf_init_debugfs(void) | |
1423 | { | |
1424 | return 0; | |
1425 | } | |
1426 | static inline void dma_buf_uninit_debugfs(void) | |
1427 | { | |
1428 | } | |
1429 | #endif | |
1430 | ||
1431 | static int __init dma_buf_init(void) | |
1432 | { | |
bdb8d06d HV |
1433 | int ret; |
1434 | ||
1435 | ret = dma_buf_init_sysfs_statistics(); | |
1436 | if (ret) | |
1437 | return ret; | |
1438 | ||
ed63bb1d GH |
1439 | dma_buf_mnt = kern_mount(&dma_buf_fs_type); |
1440 | if (IS_ERR(dma_buf_mnt)) | |
1441 | return PTR_ERR(dma_buf_mnt); | |
1442 | ||
b89e3563 SS |
1443 | mutex_init(&db_list.lock); |
1444 | INIT_LIST_HEAD(&db_list.head); | |
1445 | dma_buf_init_debugfs(); | |
1446 | return 0; | |
1447 | } | |
1448 | subsys_initcall(dma_buf_init); | |
1449 | ||
1450 | static void __exit dma_buf_deinit(void) | |
1451 | { | |
1452 | dma_buf_uninit_debugfs(); | |
ed63bb1d | 1453 | kern_unmount(dma_buf_mnt); |
bdb8d06d | 1454 | dma_buf_uninit_sysfs_statistics(); |
b89e3563 SS |
1455 | } |
1456 | __exitcall(dma_buf_deinit); |