3 * Android IPC Subsystem
5 * Copyright (C) 2007-2017 Google, Inc.
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 #include <linux/list.h>
21 #include <linux/sched/mm.h>
22 #include <linux/module.h>
23 #include <linux/rtmutex.h>
24 #include <linux/rbtree.h>
25 #include <linux/seq_file.h>
26 #include <linux/vmalloc.h>
27 #include <linux/slab.h>
28 #include <linux/sched.h>
29 #include <linux/list_lru.h>
30 #include <linux/ratelimit.h>
31 #include <asm/cacheflush.h>
32 #include "binder_alloc.h"
33 #include "binder_trace.h"
35 struct list_lru binder_alloc_lru;
37 static DEFINE_MUTEX(binder_alloc_mmap_lock);
40 BINDER_DEBUG_USER_ERROR = 1U << 0,
41 BINDER_DEBUG_OPEN_CLOSE = 1U << 1,
42 BINDER_DEBUG_BUFFER_ALLOC = 1U << 2,
43 BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 3,
45 static uint32_t binder_alloc_debug_mask = BINDER_DEBUG_USER_ERROR;
47 module_param_named(debug_mask, binder_alloc_debug_mask,
50 #define binder_alloc_debug(mask, x...) \
52 if (binder_alloc_debug_mask & mask) \
53 pr_info_ratelimited(x); \
56 static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer)
58 return list_entry(buffer->entry.next, struct binder_buffer, entry);
61 static struct binder_buffer *binder_buffer_prev(struct binder_buffer *buffer)
63 return list_entry(buffer->entry.prev, struct binder_buffer, entry);
66 static size_t binder_alloc_buffer_size(struct binder_alloc *alloc,
67 struct binder_buffer *buffer)
69 if (list_is_last(&buffer->entry, &alloc->buffers))
70 return (u8 *)alloc->buffer +
71 alloc->buffer_size - (u8 *)buffer->data;
72 return (u8 *)binder_buffer_next(buffer)->data - (u8 *)buffer->data;
75 static void binder_insert_free_buffer(struct binder_alloc *alloc,
76 struct binder_buffer *new_buffer)
78 struct rb_node **p = &alloc->free_buffers.rb_node;
79 struct rb_node *parent = NULL;
80 struct binder_buffer *buffer;
82 size_t new_buffer_size;
84 BUG_ON(!new_buffer->free);
86 new_buffer_size = binder_alloc_buffer_size(alloc, new_buffer);
88 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
89 "%d: add free buffer, size %zd, at %pK\n",
90 alloc->pid, new_buffer_size, new_buffer);
94 buffer = rb_entry(parent, struct binder_buffer, rb_node);
95 BUG_ON(!buffer->free);
97 buffer_size = binder_alloc_buffer_size(alloc, buffer);
99 if (new_buffer_size < buffer_size)
100 p = &parent->rb_left;
102 p = &parent->rb_right;
104 rb_link_node(&new_buffer->rb_node, parent, p);
105 rb_insert_color(&new_buffer->rb_node, &alloc->free_buffers);
108 static void binder_insert_allocated_buffer_locked(
109 struct binder_alloc *alloc, struct binder_buffer *new_buffer)
111 struct rb_node **p = &alloc->allocated_buffers.rb_node;
112 struct rb_node *parent = NULL;
113 struct binder_buffer *buffer;
115 BUG_ON(new_buffer->free);
119 buffer = rb_entry(parent, struct binder_buffer, rb_node);
120 BUG_ON(buffer->free);
122 if (new_buffer->data < buffer->data)
123 p = &parent->rb_left;
124 else if (new_buffer->data > buffer->data)
125 p = &parent->rb_right;
129 rb_link_node(&new_buffer->rb_node, parent, p);
130 rb_insert_color(&new_buffer->rb_node, &alloc->allocated_buffers);
133 static struct binder_buffer *binder_alloc_prepare_to_free_locked(
134 struct binder_alloc *alloc,
137 struct rb_node *n = alloc->allocated_buffers.rb_node;
138 struct binder_buffer *buffer;
141 kern_ptr = (void *)(user_ptr - alloc->user_buffer_offset);
144 buffer = rb_entry(n, struct binder_buffer, rb_node);
145 BUG_ON(buffer->free);
147 if (kern_ptr < buffer->data)
149 else if (kern_ptr > buffer->data)
153 * Guard against user threads attempting to
154 * free the buffer twice
156 if (buffer->free_in_progress) {
157 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
158 "%d:%d FREE_BUFFER u%016llx user freed buffer twice\n",
159 alloc->pid, current->pid,
163 buffer->free_in_progress = 1;
171 * binder_alloc_buffer_lookup() - get buffer given user ptr
172 * @alloc: binder_alloc for this proc
173 * @user_ptr: User pointer to buffer data
175 * Validate userspace pointer to buffer data and return buffer corresponding to
176 * that user pointer. Search the rb tree for buffer that matches user data
179 * Return: Pointer to buffer or NULL
181 struct binder_buffer *binder_alloc_prepare_to_free(struct binder_alloc *alloc,
184 struct binder_buffer *buffer;
186 mutex_lock(&alloc->mutex);
187 buffer = binder_alloc_prepare_to_free_locked(alloc, user_ptr);
188 mutex_unlock(&alloc->mutex);
192 static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
193 void *start, void *end)
196 unsigned long user_page_addr;
197 struct binder_lru_page *page;
198 struct vm_area_struct *vma = NULL;
199 struct mm_struct *mm = NULL;
200 bool need_mm = false;
202 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
203 "%d: %s pages %pK-%pK\n", alloc->pid,
204 allocate ? "allocate" : "free", start, end);
209 trace_binder_update_page_range(alloc, allocate, start, end);
214 for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) {
215 page = &alloc->pages[(page_addr - alloc->buffer) / PAGE_SIZE];
216 if (!page->page_ptr) {
222 if (need_mm && mmget_not_zero(alloc->vma_vm_mm))
223 mm = alloc->vma_vm_mm;
226 down_read(&mm->mmap_sem);
230 if (!vma && need_mm) {
231 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
232 "%d: binder_alloc_buf failed to map pages in userspace, no vma\n",
237 for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) {
242 index = (page_addr - alloc->buffer) / PAGE_SIZE;
243 page = &alloc->pages[index];
245 if (page->page_ptr) {
246 trace_binder_alloc_lru_start(alloc, index);
248 on_lru = list_lru_del(&binder_alloc_lru, &page->lru);
251 trace_binder_alloc_lru_end(alloc, index);
256 goto err_page_ptr_cleared;
258 trace_binder_alloc_page_start(alloc, index);
259 page->page_ptr = alloc_page(GFP_KERNEL |
262 if (!page->page_ptr) {
263 pr_err("%d: binder_alloc_buf failed for page at %pK\n",
264 alloc->pid, page_addr);
265 goto err_alloc_page_failed;
268 INIT_LIST_HEAD(&page->lru);
270 ret = map_kernel_range_noflush((unsigned long)page_addr,
271 PAGE_SIZE, PAGE_KERNEL,
273 flush_cache_vmap((unsigned long)page_addr,
274 (unsigned long)page_addr + PAGE_SIZE);
276 pr_err("%d: binder_alloc_buf failed to map page at %pK in kernel\n",
277 alloc->pid, page_addr);
278 goto err_map_kernel_failed;
281 (uintptr_t)page_addr + alloc->user_buffer_offset;
282 ret = vm_insert_page(vma, user_page_addr, page[0].page_ptr);
284 pr_err("%d: binder_alloc_buf failed to map page at %lx in userspace\n",
285 alloc->pid, user_page_addr);
286 goto err_vm_insert_page_failed;
289 if (index + 1 > alloc->pages_high)
290 alloc->pages_high = index + 1;
292 trace_binder_alloc_page_end(alloc, index);
293 /* vm_insert_page does not seem to increment the refcount */
296 up_read(&mm->mmap_sem);
302 for (page_addr = end - PAGE_SIZE; page_addr >= start;
303 page_addr -= PAGE_SIZE) {
307 index = (page_addr - alloc->buffer) / PAGE_SIZE;
308 page = &alloc->pages[index];
310 trace_binder_free_lru_start(alloc, index);
312 ret = list_lru_add(&binder_alloc_lru, &page->lru);
315 trace_binder_free_lru_end(alloc, index);
318 err_vm_insert_page_failed:
319 unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE);
320 err_map_kernel_failed:
321 __free_page(page->page_ptr);
322 page->page_ptr = NULL;
323 err_alloc_page_failed:
324 err_page_ptr_cleared:
329 up_read(&mm->mmap_sem);
332 return vma ? -ENOMEM : -ESRCH;
335 static struct binder_buffer *binder_alloc_new_buf_locked(
336 struct binder_alloc *alloc,
339 size_t extra_buffers_size,
342 struct rb_node *n = alloc->free_buffers.rb_node;
343 struct binder_buffer *buffer;
345 struct rb_node *best_fit = NULL;
348 size_t size, data_offsets_size;
351 if (alloc->vma == NULL) {
352 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
353 "%d: binder_alloc_buf, no vma\n",
355 return ERR_PTR(-ESRCH);
358 data_offsets_size = ALIGN(data_size, sizeof(void *)) +
359 ALIGN(offsets_size, sizeof(void *));
361 if (data_offsets_size < data_size || data_offsets_size < offsets_size) {
362 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
363 "%d: got transaction with invalid size %zd-%zd\n",
364 alloc->pid, data_size, offsets_size);
365 return ERR_PTR(-EINVAL);
367 size = data_offsets_size + ALIGN(extra_buffers_size, sizeof(void *));
368 if (size < data_offsets_size || size < extra_buffers_size) {
369 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
370 "%d: got transaction with invalid extra_buffers_size %zd\n",
371 alloc->pid, extra_buffers_size);
372 return ERR_PTR(-EINVAL);
375 alloc->free_async_space < size + sizeof(struct binder_buffer)) {
376 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
377 "%d: binder_alloc_buf size %zd failed, no async space left\n",
379 return ERR_PTR(-ENOSPC);
382 /* Pad 0-size buffers so they get assigned unique addresses */
383 size = max(size, sizeof(void *));
386 buffer = rb_entry(n, struct binder_buffer, rb_node);
387 BUG_ON(!buffer->free);
388 buffer_size = binder_alloc_buffer_size(alloc, buffer);
390 if (size < buffer_size) {
393 } else if (size > buffer_size)
400 if (best_fit == NULL) {
401 size_t allocated_buffers = 0;
402 size_t largest_alloc_size = 0;
403 size_t total_alloc_size = 0;
404 size_t free_buffers = 0;
405 size_t largest_free_size = 0;
406 size_t total_free_size = 0;
408 for (n = rb_first(&alloc->allocated_buffers); n != NULL;
410 buffer = rb_entry(n, struct binder_buffer, rb_node);
411 buffer_size = binder_alloc_buffer_size(alloc, buffer);
413 total_alloc_size += buffer_size;
414 if (buffer_size > largest_alloc_size)
415 largest_alloc_size = buffer_size;
417 for (n = rb_first(&alloc->free_buffers); n != NULL;
419 buffer = rb_entry(n, struct binder_buffer, rb_node);
420 buffer_size = binder_alloc_buffer_size(alloc, buffer);
422 total_free_size += buffer_size;
423 if (buffer_size > largest_free_size)
424 largest_free_size = buffer_size;
426 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
427 "%d: binder_alloc_buf size %zd failed, no address space\n",
429 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
430 "allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
431 total_alloc_size, allocated_buffers,
432 largest_alloc_size, total_free_size,
433 free_buffers, largest_free_size);
434 return ERR_PTR(-ENOSPC);
437 buffer = rb_entry(best_fit, struct binder_buffer, rb_node);
438 buffer_size = binder_alloc_buffer_size(alloc, buffer);
441 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
442 "%d: binder_alloc_buf size %zd got buffer %pK size %zd\n",
443 alloc->pid, size, buffer, buffer_size);
446 (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK);
447 WARN_ON(n && buffer_size != size);
449 (void *)PAGE_ALIGN((uintptr_t)buffer->data + size);
450 if (end_page_addr > has_page_addr)
451 end_page_addr = has_page_addr;
452 ret = binder_update_page_range(alloc, 1,
453 (void *)PAGE_ALIGN((uintptr_t)buffer->data), end_page_addr);
457 if (buffer_size != size) {
458 struct binder_buffer *new_buffer;
460 new_buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
462 pr_err("%s: %d failed to alloc new buffer struct\n",
463 __func__, alloc->pid);
464 goto err_alloc_buf_struct_failed;
466 new_buffer->data = (u8 *)buffer->data + size;
467 list_add(&new_buffer->entry, &buffer->entry);
468 new_buffer->free = 1;
469 binder_insert_free_buffer(alloc, new_buffer);
472 rb_erase(best_fit, &alloc->free_buffers);
474 buffer->free_in_progress = 0;
475 binder_insert_allocated_buffer_locked(alloc, buffer);
476 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
477 "%d: binder_alloc_buf size %zd got %pK\n",
478 alloc->pid, size, buffer);
479 buffer->data_size = data_size;
480 buffer->offsets_size = offsets_size;
481 buffer->async_transaction = is_async;
482 buffer->extra_buffers_size = extra_buffers_size;
484 alloc->free_async_space -= size + sizeof(struct binder_buffer);
485 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
486 "%d: binder_alloc_buf size %zd async free %zd\n",
487 alloc->pid, size, alloc->free_async_space);
491 err_alloc_buf_struct_failed:
492 binder_update_page_range(alloc, 0,
493 (void *)PAGE_ALIGN((uintptr_t)buffer->data),
495 return ERR_PTR(-ENOMEM);
499 * binder_alloc_new_buf() - Allocate a new binder buffer
500 * @alloc: binder_alloc for this proc
501 * @data_size: size of user data buffer
502 * @offsets_size: user specified buffer offset
503 * @extra_buffers_size: size of extra space for meta-data (eg, security context)
504 * @is_async: buffer for async transaction
506 * Allocate a new buffer given the requested sizes. Returns
507 * the kernel version of the buffer pointer. The size allocated
508 * is the sum of the three given sizes (each rounded up to
509 * pointer-sized boundary)
511 * Return: The allocated buffer or %NULL if error
513 struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
516 size_t extra_buffers_size,
519 struct binder_buffer *buffer;
521 mutex_lock(&alloc->mutex);
522 buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size,
523 extra_buffers_size, is_async);
524 mutex_unlock(&alloc->mutex);
528 static void *buffer_start_page(struct binder_buffer *buffer)
530 return (void *)((uintptr_t)buffer->data & PAGE_MASK);
533 static void *prev_buffer_end_page(struct binder_buffer *buffer)
535 return (void *)(((uintptr_t)(buffer->data) - 1) & PAGE_MASK);
538 static void binder_delete_free_buffer(struct binder_alloc *alloc,
539 struct binder_buffer *buffer)
541 struct binder_buffer *prev, *next = NULL;
543 BUG_ON(alloc->buffers.next == &buffer->entry);
544 prev = binder_buffer_prev(buffer);
546 if (prev_buffer_end_page(prev) == buffer_start_page(buffer)) {
548 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
549 "%d: merge free, buffer %pK share page with %pK\n",
550 alloc->pid, buffer->data, prev->data);
553 if (!list_is_last(&buffer->entry, &alloc->buffers)) {
554 next = binder_buffer_next(buffer);
555 if (buffer_start_page(next) == buffer_start_page(buffer)) {
557 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
558 "%d: merge free, buffer %pK share page with %pK\n",
565 if (PAGE_ALIGNED(buffer->data)) {
566 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
567 "%d: merge free, buffer start %pK is page aligned\n",
568 alloc->pid, buffer->data);
573 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
574 "%d: merge free, buffer %pK do not share page with %pK or %pK\n",
575 alloc->pid, buffer->data,
576 prev->data, next ? next->data : NULL);
577 binder_update_page_range(alloc, 0, buffer_start_page(buffer),
578 buffer_start_page(buffer) + PAGE_SIZE);
580 list_del(&buffer->entry);
584 static void binder_free_buf_locked(struct binder_alloc *alloc,
585 struct binder_buffer *buffer)
587 size_t size, buffer_size;
589 buffer_size = binder_alloc_buffer_size(alloc, buffer);
591 size = ALIGN(buffer->data_size, sizeof(void *)) +
592 ALIGN(buffer->offsets_size, sizeof(void *)) +
593 ALIGN(buffer->extra_buffers_size, sizeof(void *));
595 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
596 "%d: binder_free_buf %pK size %zd buffer_size %zd\n",
597 alloc->pid, buffer, size, buffer_size);
599 BUG_ON(buffer->free);
600 BUG_ON(size > buffer_size);
601 BUG_ON(buffer->transaction != NULL);
602 BUG_ON(buffer->data < alloc->buffer);
603 BUG_ON(buffer->data > alloc->buffer + alloc->buffer_size);
605 if (buffer->async_transaction) {
606 alloc->free_async_space += size + sizeof(struct binder_buffer);
608 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
609 "%d: binder_free_buf size %zd async free %zd\n",
610 alloc->pid, size, alloc->free_async_space);
613 binder_update_page_range(alloc, 0,
614 (void *)PAGE_ALIGN((uintptr_t)buffer->data),
615 (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK));
617 rb_erase(&buffer->rb_node, &alloc->allocated_buffers);
619 if (!list_is_last(&buffer->entry, &alloc->buffers)) {
620 struct binder_buffer *next = binder_buffer_next(buffer);
623 rb_erase(&next->rb_node, &alloc->free_buffers);
624 binder_delete_free_buffer(alloc, next);
627 if (alloc->buffers.next != &buffer->entry) {
628 struct binder_buffer *prev = binder_buffer_prev(buffer);
631 binder_delete_free_buffer(alloc, buffer);
632 rb_erase(&prev->rb_node, &alloc->free_buffers);
636 binder_insert_free_buffer(alloc, buffer);
640 * binder_alloc_free_buf() - free a binder buffer
641 * @alloc: binder_alloc for this proc
642 * @buffer: kernel pointer to buffer
644 * Free the buffer allocated via binder_alloc_new_buffer()
646 void binder_alloc_free_buf(struct binder_alloc *alloc,
647 struct binder_buffer *buffer)
649 mutex_lock(&alloc->mutex);
650 binder_free_buf_locked(alloc, buffer);
651 mutex_unlock(&alloc->mutex);
655 * binder_alloc_mmap_handler() - map virtual address space for proc
656 * @alloc: alloc structure for this proc
657 * @vma: vma passed to mmap()
659 * Called by binder_mmap() to initialize the space specified in
660 * vma for allocating binder buffers
664 * -EBUSY = address space already mapped
665 * -ENOMEM = failed to map memory to given address space
667 int binder_alloc_mmap_handler(struct binder_alloc *alloc,
668 struct vm_area_struct *vma)
671 struct vm_struct *area;
672 const char *failure_string;
673 struct binder_buffer *buffer;
675 mutex_lock(&binder_alloc_mmap_lock);
678 failure_string = "already mapped";
679 goto err_already_mapped;
682 area = get_vm_area(vma->vm_end - vma->vm_start, VM_ALLOC);
685 failure_string = "get_vm_area";
686 goto err_get_vm_area_failed;
688 alloc->buffer = area->addr;
689 alloc->user_buffer_offset =
690 vma->vm_start - (uintptr_t)alloc->buffer;
691 mutex_unlock(&binder_alloc_mmap_lock);
693 #ifdef CONFIG_CPU_CACHE_VIPT
694 if (cache_is_vipt_aliasing()) {
696 (vma->vm_start ^ (uint32_t)alloc->buffer))) {
697 pr_info("%s: %d %lx-%lx maps %pK bad alignment\n",
698 __func__, alloc->pid, vma->vm_start,
699 vma->vm_end, alloc->buffer);
700 vma->vm_start += PAGE_SIZE;
704 alloc->pages = kcalloc((vma->vm_end - vma->vm_start) / PAGE_SIZE,
705 sizeof(alloc->pages[0]),
707 if (alloc->pages == NULL) {
709 failure_string = "alloc page array";
710 goto err_alloc_pages_failed;
712 alloc->buffer_size = vma->vm_end - vma->vm_start;
714 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
717 failure_string = "alloc buffer struct";
718 goto err_alloc_buf_struct_failed;
721 buffer->data = alloc->buffer;
722 list_add(&buffer->entry, &alloc->buffers);
724 binder_insert_free_buffer(alloc, buffer);
725 alloc->free_async_space = alloc->buffer_size / 2;
728 alloc->vma_vm_mm = vma->vm_mm;
729 mmgrab(alloc->vma_vm_mm);
733 err_alloc_buf_struct_failed:
736 err_alloc_pages_failed:
737 mutex_lock(&binder_alloc_mmap_lock);
738 vfree(alloc->buffer);
739 alloc->buffer = NULL;
740 err_get_vm_area_failed:
742 mutex_unlock(&binder_alloc_mmap_lock);
743 binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
744 "%s: %d %lx-%lx %s failed %d\n", __func__,
745 alloc->pid, vma->vm_start, vma->vm_end,
746 failure_string, ret);
751 void binder_alloc_deferred_release(struct binder_alloc *alloc)
754 int buffers, page_count;
755 struct binder_buffer *buffer;
760 mutex_lock(&alloc->mutex);
761 while ((n = rb_first(&alloc->allocated_buffers))) {
762 buffer = rb_entry(n, struct binder_buffer, rb_node);
764 /* Transaction should already have been freed */
765 BUG_ON(buffer->transaction);
767 binder_free_buf_locked(alloc, buffer);
771 while (!list_empty(&alloc->buffers)) {
772 buffer = list_first_entry(&alloc->buffers,
773 struct binder_buffer, entry);
774 WARN_ON(!buffer->free);
776 list_del(&buffer->entry);
777 WARN_ON_ONCE(!list_empty(&alloc->buffers));
785 for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
789 if (!alloc->pages[i].page_ptr)
792 on_lru = list_lru_del(&binder_alloc_lru,
793 &alloc->pages[i].lru);
794 page_addr = alloc->buffer + i * PAGE_SIZE;
795 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
796 "%s: %d: page %d at %pK %s\n",
797 __func__, alloc->pid, i, page_addr,
798 on_lru ? "on lru" : "active");
799 unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE);
800 __free_page(alloc->pages[i].page_ptr);
804 vfree(alloc->buffer);
806 mutex_unlock(&alloc->mutex);
807 if (alloc->vma_vm_mm)
808 mmdrop(alloc->vma_vm_mm);
810 binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE,
811 "%s: %d buffers %d, pages %d\n",
812 __func__, alloc->pid, buffers, page_count);
815 static void print_binder_buffer(struct seq_file *m, const char *prefix,
816 struct binder_buffer *buffer)
818 seq_printf(m, "%s %d: %pK size %zd:%zd:%zd %s\n",
819 prefix, buffer->debug_id, buffer->data,
820 buffer->data_size, buffer->offsets_size,
821 buffer->extra_buffers_size,
822 buffer->transaction ? "active" : "delivered");
826 * binder_alloc_print_allocated() - print buffer info
827 * @m: seq_file for output via seq_printf()
828 * @alloc: binder_alloc for this proc
830 * Prints information about every buffer associated with
831 * the binder_alloc state to the given seq_file
833 void binder_alloc_print_allocated(struct seq_file *m,
834 struct binder_alloc *alloc)
838 mutex_lock(&alloc->mutex);
839 for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n))
840 print_binder_buffer(m, " buffer",
841 rb_entry(n, struct binder_buffer, rb_node));
842 mutex_unlock(&alloc->mutex);
846 * binder_alloc_print_pages() - print page usage
847 * @m: seq_file for output via seq_printf()
848 * @alloc: binder_alloc for this proc
850 void binder_alloc_print_pages(struct seq_file *m,
851 struct binder_alloc *alloc)
853 struct binder_lru_page *page;
859 mutex_lock(&alloc->mutex);
860 for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
861 page = &alloc->pages[i];
864 else if (list_empty(&page->lru))
869 mutex_unlock(&alloc->mutex);
870 seq_printf(m, " pages: %d:%d:%d\n", active, lru, free);
871 seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high);
875 * binder_alloc_get_allocated_count() - return count of buffers
876 * @alloc: binder_alloc for this proc
878 * Return: count of allocated buffers
880 int binder_alloc_get_allocated_count(struct binder_alloc *alloc)
885 mutex_lock(&alloc->mutex);
886 for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n))
888 mutex_unlock(&alloc->mutex);
894 * binder_alloc_vma_close() - invalidate address space
895 * @alloc: binder_alloc for this proc
897 * Called from binder_vma_close() when releasing address space.
898 * Clears alloc->vma to prevent new incoming transactions from
899 * allocating more buffers.
901 void binder_alloc_vma_close(struct binder_alloc *alloc)
903 WRITE_ONCE(alloc->vma, NULL);
907 * binder_alloc_free_page() - shrinker callback to free pages
908 * @item: item to free
909 * @lock: lock protecting the item
910 * @cb_arg: callback argument
912 * Called from list_lru_walk() in binder_shrink_scan() to free
913 * up pages when the system is under memory pressure.
915 enum lru_status binder_alloc_free_page(struct list_head *item,
916 struct list_lru_one *lru,
920 struct mm_struct *mm = NULL;
921 struct binder_lru_page *page = container_of(item,
922 struct binder_lru_page,
924 struct binder_alloc *alloc;
927 struct vm_area_struct *vma;
930 if (!mutex_trylock(&alloc->mutex))
931 goto err_get_alloc_mutex_failed;
934 goto err_page_already_freed;
936 index = page - alloc->pages;
937 page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE;
940 if (!mmget_not_zero(alloc->vma_vm_mm))
942 mm = alloc->vma_vm_mm;
943 if (!down_write_trylock(&mm->mmap_sem))
944 goto err_down_write_mmap_sem_failed;
947 list_lru_isolate(lru, item);
951 trace_binder_unmap_user_start(alloc, index);
954 page_addr + alloc->user_buffer_offset,
957 trace_binder_unmap_user_end(alloc, index);
959 up_write(&mm->mmap_sem);
963 trace_binder_unmap_kernel_start(alloc, index);
965 unmap_kernel_range(page_addr, PAGE_SIZE);
966 __free_page(page->page_ptr);
967 page->page_ptr = NULL;
969 trace_binder_unmap_kernel_end(alloc, index);
972 mutex_unlock(&alloc->mutex);
973 return LRU_REMOVED_RETRY;
975 err_down_write_mmap_sem_failed:
978 err_page_already_freed:
979 mutex_unlock(&alloc->mutex);
980 err_get_alloc_mutex_failed:
985 binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
987 unsigned long ret = list_lru_count(&binder_alloc_lru);
992 binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
996 ret = list_lru_walk(&binder_alloc_lru, binder_alloc_free_page,
997 NULL, sc->nr_to_scan);
1001 static struct shrinker binder_shrinker = {
1002 .count_objects = binder_shrink_count,
1003 .scan_objects = binder_shrink_scan,
1004 .seeks = DEFAULT_SEEKS,
1008 * binder_alloc_init() - called by binder_open() for per-proc initialization
1009 * @alloc: binder_alloc for this proc
1011 * Called from binder_open() to initialize binder_alloc fields for
1014 void binder_alloc_init(struct binder_alloc *alloc)
1016 alloc->pid = current->group_leader->pid;
1017 mutex_init(&alloc->mutex);
1018 INIT_LIST_HEAD(&alloc->buffers);
1021 int binder_alloc_shrinker_init(void)
1023 int ret = list_lru_init(&binder_alloc_lru);
1026 ret = register_shrinker(&binder_shrinker);
1028 list_lru_destroy(&binder_alloc_lru);