1 /**************************************************************************
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 **************************************************************************/
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
31 * Copyright (c) 2013 The FreeBSD Foundation
32 * All rights reserved.
34 * Portions of this software were developed by Konstantin Belousov
35 * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
43 #include <dev/drm2/drmP.h>
44 #include <dev/drm2/ttm/ttm_module.h>
45 #include <dev/drm2/ttm/ttm_bo_driver.h>
46 #include <dev/drm2/ttm/ttm_placement.h>
49 #include <vm/vm_page.h>
50 #include <vm/vm_pageout.h>
52 #define TTM_BO_VM_NUM_PREFAULT 16
54 RB_GENERATE(ttm_bo_device_buffer_objects, ttm_buffer_object, vm_rb,
55 ttm_bo_cmp_rb_tree_items);
58 ttm_bo_cmp_rb_tree_items(struct ttm_buffer_object *a,
59 struct ttm_buffer_object *b)
62 if (a->vm_node->start < b->vm_node->start) {
64 } else if (a->vm_node->start > b->vm_node->start) {
71 static struct ttm_buffer_object *ttm_bo_vm_lookup_rb(struct ttm_bo_device *bdev,
72 unsigned long page_start,
73 unsigned long num_pages)
75 unsigned long cur_offset;
76 struct ttm_buffer_object *bo;
77 struct ttm_buffer_object *best_bo = NULL;
79 bo = RB_ROOT(&bdev->addr_space_rb);
81 cur_offset = bo->vm_node->start;
82 if (page_start >= cur_offset) {
84 if (page_start == cur_offset)
86 bo = RB_RIGHT(bo, vm_rb);
88 bo = RB_LEFT(bo, vm_rb);
91 if (unlikely(best_bo == NULL))
94 if (unlikely((best_bo->vm_node->start + best_bo->num_pages) <
95 (page_start + num_pages)))
102 ttm_bo_vm_fault(vm_object_t vm_obj, vm_ooffset_t offset,
103 int prot, vm_page_t *mres)
106 struct ttm_buffer_object *bo = vm_obj->handle;
107 struct ttm_bo_device *bdev = bo->bdev;
108 struct ttm_tt *ttm = NULL;
111 int retval = VM_PAGER_OK;
112 struct ttm_mem_type_manager *man =
113 &bdev->man[bo->mem.mem_type];
115 vm_object_pip_add(vm_obj, 1);
118 vm_page_remove(*mres);
119 vm_page_unlock(*mres);
122 VM_OBJECT_WUNLOCK(vm_obj);
126 ret = ttm_bo_reserve(bo, false, false, false, 0);
127 if (unlikely(ret != 0)) {
134 if (bdev->driver->fault_reserve_notify) {
135 ret = bdev->driver->fault_reserve_notify(bo);
145 retval = VM_PAGER_ERROR;
151 * Wait for buffer data in transit, due to a pipelined
155 mtx_lock(&bdev->fence_lock);
156 if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
158 * Here, the behavior differs between Linux and FreeBSD.
160 * On Linux, the wait is interruptible (3rd argument to
161 * ttm_bo_wait). There must be some mechanism to resume
162 * page fault handling, once the signal is processed.
164 * On FreeBSD, the wait is uninteruptible. This is not a
165 * problem as we can't end up with an unkillable process
166 * here, because the wait will eventually time out.
168 * An example of this situation is the Xorg process
169 * which uses SIGALRM internally. The signal could
170 * interrupt the wait, causing the page fault to fail
171 * and the process to receive SIGSEGV.
173 ret = ttm_bo_wait(bo, false, false, false);
174 mtx_unlock(&bdev->fence_lock);
175 if (unlikely(ret != 0)) {
176 retval = VM_PAGER_ERROR;
180 mtx_unlock(&bdev->fence_lock);
182 ret = ttm_mem_io_lock(man, true);
183 if (unlikely(ret != 0)) {
184 retval = VM_PAGER_ERROR;
187 ret = ttm_mem_io_reserve_vm(bo);
188 if (unlikely(ret != 0)) {
189 retval = VM_PAGER_ERROR;
194 * Strictly, we're not allowed to modify vma->vm_page_prot here,
195 * since the mmap_sem is only held in read mode. However, we
196 * modify only the caching bits of vma->vm_page_prot and
197 * consider those bits protected by
198 * the bo->mutex, as we should be the only writers.
199 * There shouldn't really be any readers of these bits except
200 * within vm_insert_mixed()? fork?
202 * TODO: Add a list of vmas to the bo, and change the
203 * vma->vm_page_prot when the object changes caching policy, with
204 * the correct locks held.
206 if (!bo->mem.bus.is_iomem) {
207 /* Allocate all page at once, most common usage */
209 if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
210 retval = VM_PAGER_ERROR;
215 if (bo->mem.bus.is_iomem) {
216 m = PHYS_TO_VM_PAGE(bo->mem.bus.base + bo->mem.bus.offset +
218 KASSERT((m->flags & PG_FICTITIOUS) != 0,
219 ("physical address %#jx not fictitious",
220 (uintmax_t)(bo->mem.bus.base + bo->mem.bus.offset
222 pmap_page_set_memattr(m, ttm_io_prot(bo->mem.placement));
225 m = ttm->pages[OFF_TO_IDX(offset)];
227 retval = VM_PAGER_ERROR;
230 pmap_page_set_memattr(m,
231 (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
232 VM_MEMATTR_WRITE_BACK : ttm_io_prot(bo->mem.placement));
235 VM_OBJECT_WLOCK(vm_obj);
236 if (vm_page_busied(m)) {
238 VM_OBJECT_WUNLOCK(vm_obj);
239 vm_page_busy_sleep(m, "ttmpbs", false);
240 VM_OBJECT_WLOCK(vm_obj);
241 ttm_mem_io_unlock(man);
242 ttm_bo_unreserve(bo);
245 m1 = vm_page_lookup(vm_obj, OFF_TO_IDX(offset));
247 if (vm_page_insert(m, vm_obj, OFF_TO_IDX(offset))) {
248 VM_OBJECT_WUNLOCK(vm_obj);
250 VM_OBJECT_WLOCK(vm_obj);
251 ttm_mem_io_unlock(man);
252 ttm_bo_unreserve(bo);
257 ("inconsistent insert bo %p m %p m1 %p offset %jx",
258 bo, m, m1, (uintmax_t)offset));
260 m->valid = VM_PAGE_BITS_ALL;
263 KASSERT(*mres != m, ("losing %p %p", *mres, m));
266 vm_page_unlock(*mres);
271 ttm_mem_io_unlock(man);
273 ttm_bo_unreserve(bo);
274 vm_object_pip_wakeup(vm_obj);
278 VM_OBJECT_WLOCK(vm_obj);
282 VM_OBJECT_WLOCK(vm_obj);
287 ttm_bo_vm_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
288 vm_ooffset_t foff, struct ucred *cred, u_short *color)
292 * On Linux, a reference to the buffer object is acquired here.
293 * The reason is that this function is not called when the
294 * mmap() is initialized, but only when a process forks for
295 * instance. Therefore on Linux, the reference on the bo is
296 * acquired either in ttm_bo_mmap() or ttm_bo_vm_open(). It's
297 * then released in ttm_bo_vm_close().
299 * Here, this function is called during mmap() initialization.
300 * Thus, the reference acquired in ttm_bo_mmap_single() is
309 ttm_bo_vm_dtor(void *handle)
311 struct ttm_buffer_object *bo = handle;
316 static struct cdev_pager_ops ttm_pager_ops = {
317 .cdev_pg_fault = ttm_bo_vm_fault,
318 .cdev_pg_ctor = ttm_bo_vm_ctor,
319 .cdev_pg_dtor = ttm_bo_vm_dtor
323 ttm_bo_mmap_single(struct ttm_bo_device *bdev, vm_ooffset_t *offset, vm_size_t size,
324 struct vm_object **obj_res, int nprot)
326 struct ttm_bo_driver *driver;
327 struct ttm_buffer_object *bo;
328 struct vm_object *vm_obj;
331 rw_wlock(&bdev->vm_lock);
332 bo = ttm_bo_vm_lookup_rb(bdev, OFF_TO_IDX(*offset), OFF_TO_IDX(size));
333 if (likely(bo != NULL))
334 refcount_acquire(&bo->kref);
335 rw_wunlock(&bdev->vm_lock);
337 if (unlikely(bo == NULL)) {
338 printf("[TTM] Could not find buffer object to map\n");
342 driver = bo->bdev->driver;
343 if (unlikely(!driver->verify_access)) {
347 ret = driver->verify_access(bo);
348 if (unlikely(ret != 0))
351 vm_obj = cdev_pager_allocate(bo, OBJT_MGTDEVICE, &ttm_pager_ops,
352 size, nprot, 0, curthread->td_ucred);
353 if (vm_obj == NULL) {
358 * Note: We're transferring the bo reference to vm_obj->handle here.
369 ttm_bo_release_mmap(struct ttm_buffer_object *bo)
375 vm_obj = cdev_pager_lookup(bo);
379 VM_OBJECT_WLOCK(vm_obj);
381 for (i = 0; i < bo->num_pages; i++) {
382 m = vm_page_lookup(vm_obj, i);
385 if (vm_page_sleep_if_busy(m, "ttm_unm"))
387 cdev_pager_free_page(vm_obj, m);
389 VM_OBJECT_WUNLOCK(vm_obj);
391 vm_object_deallocate(vm_obj);
395 int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
397 if (vma->vm_pgoff != 0)
400 vma->vm_ops = &ttm_bo_vm_ops;
401 vma->vm_private_data = ttm_bo_reference(bo);
402 vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
406 ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
407 const char __user *wbuf, char __user *rbuf, size_t count,
408 loff_t *f_pos, bool write)
410 struct ttm_buffer_object *bo;
411 struct ttm_bo_driver *driver;
412 struct ttm_bo_kmap_obj map;
413 unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
414 unsigned long kmap_offset;
415 unsigned long kmap_end;
416 unsigned long kmap_num;
418 unsigned int page_offset;
421 bool no_wait = false;
424 read_lock(&bdev->vm_lock);
425 bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
426 if (likely(bo != NULL))
427 ttm_bo_reference(bo);
428 read_unlock(&bdev->vm_lock);
430 if (unlikely(bo == NULL))
433 driver = bo->bdev->driver;
434 if (unlikely(!driver->verify_access)) {
439 ret = driver->verify_access(bo, filp);
440 if (unlikely(ret != 0))
443 kmap_offset = dev_offset - bo->vm_node->start;
444 if (unlikely(kmap_offset >= bo->num_pages)) {
449 page_offset = *f_pos & ~PAGE_MASK;
450 io_size = bo->num_pages - kmap_offset;
451 io_size = (io_size << PAGE_SHIFT) - page_offset;
455 kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
456 kmap_num = kmap_end - kmap_offset + 1;
458 ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
470 ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
471 if (unlikely(ret != 0)) {
472 ttm_bo_unreserve(bo);
476 virtual = ttm_kmap_obj_virtual(&map, &dummy);
477 virtual += page_offset;
480 ret = copy_from_user(virtual, wbuf, io_size);
482 ret = copy_to_user(rbuf, virtual, io_size);
485 ttm_bo_unreserve(bo);
488 if (unlikely(ret != 0))
499 ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object *bo, const char __user *wbuf,
500 char __user *rbuf, size_t count, loff_t *f_pos,
503 struct ttm_bo_kmap_obj map;
504 unsigned long kmap_offset;
505 unsigned long kmap_end;
506 unsigned long kmap_num;
508 unsigned int page_offset;
511 bool no_wait = false;
514 kmap_offset = (*f_pos >> PAGE_SHIFT);
515 if (unlikely(kmap_offset >= bo->num_pages))
518 page_offset = *f_pos & ~PAGE_MASK;
519 io_size = bo->num_pages - kmap_offset;
520 io_size = (io_size << PAGE_SHIFT) - page_offset;
524 kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
525 kmap_num = kmap_end - kmap_offset + 1;
527 ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
538 ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
539 if (unlikely(ret != 0)) {
540 ttm_bo_unreserve(bo);
544 virtual = ttm_kmap_obj_virtual(&map, &dummy);
545 virtual += page_offset;
548 ret = copy_from_user(virtual, wbuf, io_size);
550 ret = copy_to_user(rbuf, virtual, io_size);
553 ttm_bo_unreserve(bo);
556 if (unlikely(ret != 0))