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 <asm/cacheflush.h>
21 #include <linux/list.h>
22 #include <linux/sched/mm.h>
23 #include <linux/module.h>
24 #include <linux/rtmutex.h>
25 #include <linux/rbtree.h>
26 #include <linux/seq_file.h>
27 #include <linux/vmalloc.h>
28 #include <linux/slab.h>
29 #include <linux/sched.h>
30 #include <linux/list_lru.h>
31 #include "binder_alloc.h"
32 #include "binder_trace.h"
34 struct list_lru binder_alloc_lru;
36 static DEFINE_MUTEX(binder_alloc_mmap_lock);
39 BINDER_DEBUG_OPEN_CLOSE = 1U << 1,
40 BINDER_DEBUG_BUFFER_ALLOC = 1U << 2,
41 BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 3,
43 static uint32_t binder_alloc_debug_mask;
45 module_param_named(debug_mask, binder_alloc_debug_mask,
48 #define binder_alloc_debug(mask, x...) \
50 if (binder_alloc_debug_mask & mask) \
54 static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer)
56 return list_entry(buffer->entry.next, struct binder_buffer, entry);
59 static struct binder_buffer *binder_buffer_prev(struct binder_buffer *buffer)
61 return list_entry(buffer->entry.prev, struct binder_buffer, entry);
64 static size_t binder_alloc_buffer_size(struct binder_alloc *alloc,
65 struct binder_buffer *buffer)
67 if (list_is_last(&buffer->entry, &alloc->buffers))
68 return (u8 *)alloc->buffer +
69 alloc->buffer_size - (u8 *)buffer->data;
70 return (u8 *)binder_buffer_next(buffer)->data - (u8 *)buffer->data;
73 static void binder_insert_free_buffer(struct binder_alloc *alloc,
74 struct binder_buffer *new_buffer)
76 struct rb_node **p = &alloc->free_buffers.rb_node;
77 struct rb_node *parent = NULL;
78 struct binder_buffer *buffer;
80 size_t new_buffer_size;
82 BUG_ON(!new_buffer->free);
84 new_buffer_size = binder_alloc_buffer_size(alloc, new_buffer);
86 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
87 "%d: add free buffer, size %zd, at %pK\n",
88 alloc->pid, new_buffer_size, new_buffer);
92 buffer = rb_entry(parent, struct binder_buffer, rb_node);
93 BUG_ON(!buffer->free);
95 buffer_size = binder_alloc_buffer_size(alloc, buffer);
97 if (new_buffer_size < buffer_size)
100 p = &parent->rb_right;
102 rb_link_node(&new_buffer->rb_node, parent, p);
103 rb_insert_color(&new_buffer->rb_node, &alloc->free_buffers);
106 static void binder_insert_allocated_buffer_locked(
107 struct binder_alloc *alloc, struct binder_buffer *new_buffer)
109 struct rb_node **p = &alloc->allocated_buffers.rb_node;
110 struct rb_node *parent = NULL;
111 struct binder_buffer *buffer;
113 BUG_ON(new_buffer->free);
117 buffer = rb_entry(parent, struct binder_buffer, rb_node);
118 BUG_ON(buffer->free);
120 if (new_buffer->data < buffer->data)
121 p = &parent->rb_left;
122 else if (new_buffer->data > buffer->data)
123 p = &parent->rb_right;
127 rb_link_node(&new_buffer->rb_node, parent, p);
128 rb_insert_color(&new_buffer->rb_node, &alloc->allocated_buffers);
131 static struct binder_buffer *binder_alloc_prepare_to_free_locked(
132 struct binder_alloc *alloc,
135 struct rb_node *n = alloc->allocated_buffers.rb_node;
136 struct binder_buffer *buffer;
139 kern_ptr = (void *)(user_ptr - alloc->user_buffer_offset);
142 buffer = rb_entry(n, struct binder_buffer, rb_node);
143 BUG_ON(buffer->free);
145 if (kern_ptr < buffer->data)
147 else if (kern_ptr > buffer->data)
151 * Guard against user threads attempting to
152 * free the buffer twice
154 if (buffer->free_in_progress) {
155 pr_err("%d:%d FREE_BUFFER u%016llx user freed buffer twice\n",
156 alloc->pid, current->pid, (u64)user_ptr);
159 buffer->free_in_progress = 1;
167 * binder_alloc_buffer_lookup() - get buffer given user ptr
168 * @alloc: binder_alloc for this proc
169 * @user_ptr: User pointer to buffer data
171 * Validate userspace pointer to buffer data and return buffer corresponding to
172 * that user pointer. Search the rb tree for buffer that matches user data
175 * Return: Pointer to buffer or NULL
177 struct binder_buffer *binder_alloc_prepare_to_free(struct binder_alloc *alloc,
180 struct binder_buffer *buffer;
182 mutex_lock(&alloc->mutex);
183 buffer = binder_alloc_prepare_to_free_locked(alloc, user_ptr);
184 mutex_unlock(&alloc->mutex);
188 static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
189 void *start, void *end,
190 struct vm_area_struct *vma)
193 unsigned long user_page_addr;
194 struct binder_lru_page *page;
195 struct mm_struct *mm = NULL;
196 bool need_mm = false;
198 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
199 "%d: %s pages %pK-%pK\n", alloc->pid,
200 allocate ? "allocate" : "free", start, end);
205 trace_binder_update_page_range(alloc, allocate, start, end);
210 for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) {
211 page = &alloc->pages[(page_addr - alloc->buffer) / PAGE_SIZE];
212 if (!page->page_ptr) {
219 mm = get_task_mm(alloc->tsk);
222 down_write(&mm->mmap_sem);
224 if (vma && mm != alloc->vma_vm_mm) {
225 pr_err("%d: vma mm and task mm mismatch\n",
231 if (!vma && need_mm) {
232 pr_err("%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 trace_binder_alloc_page_end(alloc, index);
290 /* vm_insert_page does not seem to increment the refcount */
293 up_write(&mm->mmap_sem);
299 for (page_addr = end - PAGE_SIZE; page_addr >= start;
300 page_addr -= PAGE_SIZE) {
304 index = (page_addr - alloc->buffer) / PAGE_SIZE;
305 page = &alloc->pages[index];
307 trace_binder_free_lru_start(alloc, index);
309 ret = list_lru_add(&binder_alloc_lru, &page->lru);
312 trace_binder_free_lru_end(alloc, index);
315 err_vm_insert_page_failed:
316 unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE);
317 err_map_kernel_failed:
318 __free_page(page->page_ptr);
319 page->page_ptr = NULL;
320 err_alloc_page_failed:
321 err_page_ptr_cleared:
326 up_write(&mm->mmap_sem);
329 return vma ? -ENOMEM : -ESRCH;
332 struct binder_buffer *binder_alloc_new_buf_locked(struct binder_alloc *alloc,
335 size_t extra_buffers_size,
338 struct rb_node *n = alloc->free_buffers.rb_node;
339 struct binder_buffer *buffer;
341 struct rb_node *best_fit = NULL;
344 size_t size, data_offsets_size;
347 if (alloc->vma == NULL) {
348 pr_err("%d: binder_alloc_buf, no vma\n",
350 return ERR_PTR(-ESRCH);
353 data_offsets_size = ALIGN(data_size, sizeof(void *)) +
354 ALIGN(offsets_size, sizeof(void *));
356 if (data_offsets_size < data_size || data_offsets_size < offsets_size) {
357 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
358 "%d: got transaction with invalid size %zd-%zd\n",
359 alloc->pid, data_size, offsets_size);
360 return ERR_PTR(-EINVAL);
362 size = data_offsets_size + ALIGN(extra_buffers_size, sizeof(void *));
363 if (size < data_offsets_size || size < extra_buffers_size) {
364 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
365 "%d: got transaction with invalid extra_buffers_size %zd\n",
366 alloc->pid, extra_buffers_size);
367 return ERR_PTR(-EINVAL);
370 alloc->free_async_space < size + sizeof(struct binder_buffer)) {
371 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
372 "%d: binder_alloc_buf size %zd failed, no async space left\n",
374 return ERR_PTR(-ENOSPC);
377 /* Pad 0-size buffers so they get assigned unique addresses */
378 size = max(size, sizeof(void *));
381 buffer = rb_entry(n, struct binder_buffer, rb_node);
382 BUG_ON(!buffer->free);
383 buffer_size = binder_alloc_buffer_size(alloc, buffer);
385 if (size < buffer_size) {
388 } else if (size > buffer_size)
395 if (best_fit == NULL) {
396 size_t allocated_buffers = 0;
397 size_t largest_alloc_size = 0;
398 size_t total_alloc_size = 0;
399 size_t free_buffers = 0;
400 size_t largest_free_size = 0;
401 size_t total_free_size = 0;
403 for (n = rb_first(&alloc->allocated_buffers); n != NULL;
405 buffer = rb_entry(n, struct binder_buffer, rb_node);
406 buffer_size = binder_alloc_buffer_size(alloc, buffer);
408 total_alloc_size += buffer_size;
409 if (buffer_size > largest_alloc_size)
410 largest_alloc_size = buffer_size;
412 for (n = rb_first(&alloc->free_buffers); n != NULL;
414 buffer = rb_entry(n, struct binder_buffer, rb_node);
415 buffer_size = binder_alloc_buffer_size(alloc, buffer);
417 total_free_size += buffer_size;
418 if (buffer_size > largest_free_size)
419 largest_free_size = buffer_size;
421 pr_err("%d: binder_alloc_buf size %zd failed, no address space\n",
423 pr_err("allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
424 total_alloc_size, allocated_buffers, largest_alloc_size,
425 total_free_size, free_buffers, largest_free_size);
426 return ERR_PTR(-ENOSPC);
429 buffer = rb_entry(best_fit, struct binder_buffer, rb_node);
430 buffer_size = binder_alloc_buffer_size(alloc, buffer);
433 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
434 "%d: binder_alloc_buf size %zd got buffer %pK size %zd\n",
435 alloc->pid, size, buffer, buffer_size);
438 (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK);
439 WARN_ON(n && buffer_size != size);
441 (void *)PAGE_ALIGN((uintptr_t)buffer->data + size);
442 if (end_page_addr > has_page_addr)
443 end_page_addr = has_page_addr;
444 ret = binder_update_page_range(alloc, 1,
445 (void *)PAGE_ALIGN((uintptr_t)buffer->data), end_page_addr, NULL);
449 if (buffer_size != size) {
450 struct binder_buffer *new_buffer;
452 new_buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
454 pr_err("%s: %d failed to alloc new buffer struct\n",
455 __func__, alloc->pid);
456 goto err_alloc_buf_struct_failed;
458 new_buffer->data = (u8 *)buffer->data + size;
459 list_add(&new_buffer->entry, &buffer->entry);
460 new_buffer->free = 1;
461 binder_insert_free_buffer(alloc, new_buffer);
464 rb_erase(best_fit, &alloc->free_buffers);
466 buffer->free_in_progress = 0;
467 binder_insert_allocated_buffer_locked(alloc, buffer);
468 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
469 "%d: binder_alloc_buf size %zd got %pK\n",
470 alloc->pid, size, buffer);
471 buffer->data_size = data_size;
472 buffer->offsets_size = offsets_size;
473 buffer->async_transaction = is_async;
474 buffer->extra_buffers_size = extra_buffers_size;
476 alloc->free_async_space -= size + sizeof(struct binder_buffer);
477 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
478 "%d: binder_alloc_buf size %zd async free %zd\n",
479 alloc->pid, size, alloc->free_async_space);
483 err_alloc_buf_struct_failed:
484 binder_update_page_range(alloc, 0,
485 (void *)PAGE_ALIGN((uintptr_t)buffer->data),
486 end_page_addr, NULL);
487 return ERR_PTR(-ENOMEM);
491 * binder_alloc_new_buf() - Allocate a new binder buffer
492 * @alloc: binder_alloc for this proc
493 * @data_size: size of user data buffer
494 * @offsets_size: user specified buffer offset
495 * @extra_buffers_size: size of extra space for meta-data (eg, security context)
496 * @is_async: buffer for async transaction
498 * Allocate a new buffer given the requested sizes. Returns
499 * the kernel version of the buffer pointer. The size allocated
500 * is the sum of the three given sizes (each rounded up to
501 * pointer-sized boundary)
503 * Return: The allocated buffer or %NULL if error
505 struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
508 size_t extra_buffers_size,
511 struct binder_buffer *buffer;
513 mutex_lock(&alloc->mutex);
514 buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size,
515 extra_buffers_size, is_async);
516 mutex_unlock(&alloc->mutex);
520 static void *buffer_start_page(struct binder_buffer *buffer)
522 return (void *)((uintptr_t)buffer->data & PAGE_MASK);
525 static void *prev_buffer_end_page(struct binder_buffer *buffer)
527 return (void *)(((uintptr_t)(buffer->data) - 1) & PAGE_MASK);
530 static void binder_delete_free_buffer(struct binder_alloc *alloc,
531 struct binder_buffer *buffer)
533 struct binder_buffer *prev, *next = NULL;
535 BUG_ON(alloc->buffers.next == &buffer->entry);
536 prev = binder_buffer_prev(buffer);
538 if (prev_buffer_end_page(prev) == buffer_start_page(buffer)) {
540 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
541 "%d: merge free, buffer %pK share page with %pK\n",
542 alloc->pid, buffer->data, prev->data);
545 if (!list_is_last(&buffer->entry, &alloc->buffers)) {
546 next = binder_buffer_next(buffer);
547 if (buffer_start_page(next) == buffer_start_page(buffer)) {
549 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
550 "%d: merge free, buffer %pK share page with %pK\n",
557 if (PAGE_ALIGNED(buffer->data)) {
558 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
559 "%d: merge free, buffer start %pK is page aligned\n",
560 alloc->pid, buffer->data);
565 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
566 "%d: merge free, buffer %pK do not share page with %pK or %pK\n",
567 alloc->pid, buffer->data,
568 prev->data, next->data);
569 binder_update_page_range(alloc, 0, buffer_start_page(buffer),
570 buffer_start_page(buffer) + PAGE_SIZE,
573 list_del(&buffer->entry);
577 static void binder_free_buf_locked(struct binder_alloc *alloc,
578 struct binder_buffer *buffer)
580 size_t size, buffer_size;
582 buffer_size = binder_alloc_buffer_size(alloc, buffer);
584 size = ALIGN(buffer->data_size, sizeof(void *)) +
585 ALIGN(buffer->offsets_size, sizeof(void *)) +
586 ALIGN(buffer->extra_buffers_size, sizeof(void *));
588 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
589 "%d: binder_free_buf %pK size %zd buffer_size %zd\n",
590 alloc->pid, buffer, size, buffer_size);
592 BUG_ON(buffer->free);
593 BUG_ON(size > buffer_size);
594 BUG_ON(buffer->transaction != NULL);
595 BUG_ON(buffer->data < alloc->buffer);
596 BUG_ON(buffer->data > alloc->buffer + alloc->buffer_size);
598 if (buffer->async_transaction) {
599 alloc->free_async_space += size + sizeof(struct binder_buffer);
601 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
602 "%d: binder_free_buf size %zd async free %zd\n",
603 alloc->pid, size, alloc->free_async_space);
606 binder_update_page_range(alloc, 0,
607 (void *)PAGE_ALIGN((uintptr_t)buffer->data),
608 (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK),
611 rb_erase(&buffer->rb_node, &alloc->allocated_buffers);
613 if (!list_is_last(&buffer->entry, &alloc->buffers)) {
614 struct binder_buffer *next = binder_buffer_next(buffer);
617 rb_erase(&next->rb_node, &alloc->free_buffers);
618 binder_delete_free_buffer(alloc, next);
621 if (alloc->buffers.next != &buffer->entry) {
622 struct binder_buffer *prev = binder_buffer_prev(buffer);
625 binder_delete_free_buffer(alloc, buffer);
626 rb_erase(&prev->rb_node, &alloc->free_buffers);
630 binder_insert_free_buffer(alloc, buffer);
634 * binder_alloc_free_buf() - free a binder buffer
635 * @alloc: binder_alloc for this proc
636 * @buffer: kernel pointer to buffer
638 * Free the buffer allocated via binder_alloc_new_buffer()
640 void binder_alloc_free_buf(struct binder_alloc *alloc,
641 struct binder_buffer *buffer)
643 mutex_lock(&alloc->mutex);
644 binder_free_buf_locked(alloc, buffer);
645 mutex_unlock(&alloc->mutex);
649 * binder_alloc_mmap_handler() - map virtual address space for proc
650 * @alloc: alloc structure for this proc
651 * @vma: vma passed to mmap()
653 * Called by binder_mmap() to initialize the space specified in
654 * vma for allocating binder buffers
658 * -EBUSY = address space already mapped
659 * -ENOMEM = failed to map memory to given address space
661 int binder_alloc_mmap_handler(struct binder_alloc *alloc,
662 struct vm_area_struct *vma)
665 struct vm_struct *area;
666 const char *failure_string;
667 struct binder_buffer *buffer;
669 mutex_lock(&binder_alloc_mmap_lock);
672 failure_string = "already mapped";
673 goto err_already_mapped;
676 area = get_vm_area(vma->vm_end - vma->vm_start, VM_IOREMAP);
679 failure_string = "get_vm_area";
680 goto err_get_vm_area_failed;
682 alloc->buffer = area->addr;
683 alloc->user_buffer_offset =
684 vma->vm_start - (uintptr_t)alloc->buffer;
685 mutex_unlock(&binder_alloc_mmap_lock);
687 #ifdef CONFIG_CPU_CACHE_VIPT
688 if (cache_is_vipt_aliasing()) {
690 (vma->vm_start ^ (uint32_t)alloc->buffer))) {
691 pr_info("%s: %d %lx-%lx maps %pK bad alignment\n",
692 __func__, alloc->pid, vma->vm_start,
693 vma->vm_end, alloc->buffer);
694 vma->vm_start += PAGE_SIZE;
698 alloc->pages = kzalloc(sizeof(alloc->pages[0]) *
699 ((vma->vm_end - vma->vm_start) / PAGE_SIZE),
701 if (alloc->pages == NULL) {
703 failure_string = "alloc page array";
704 goto err_alloc_pages_failed;
706 alloc->buffer_size = vma->vm_end - vma->vm_start;
708 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
711 failure_string = "alloc buffer struct";
712 goto err_alloc_buf_struct_failed;
715 buffer->data = alloc->buffer;
716 list_add(&buffer->entry, &alloc->buffers);
718 binder_insert_free_buffer(alloc, buffer);
719 alloc->free_async_space = alloc->buffer_size / 2;
722 alloc->vma_vm_mm = vma->vm_mm;
726 err_alloc_buf_struct_failed:
729 err_alloc_pages_failed:
730 mutex_lock(&binder_alloc_mmap_lock);
731 vfree(alloc->buffer);
732 alloc->buffer = NULL;
733 err_get_vm_area_failed:
735 mutex_unlock(&binder_alloc_mmap_lock);
736 pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
737 alloc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
742 void binder_alloc_deferred_release(struct binder_alloc *alloc)
745 int buffers, page_count;
746 struct binder_buffer *buffer;
751 mutex_lock(&alloc->mutex);
752 while ((n = rb_first(&alloc->allocated_buffers))) {
753 buffer = rb_entry(n, struct binder_buffer, rb_node);
755 /* Transaction should already have been freed */
756 BUG_ON(buffer->transaction);
758 binder_free_buf_locked(alloc, buffer);
762 while (!list_empty(&alloc->buffers)) {
763 buffer = list_first_entry(&alloc->buffers,
764 struct binder_buffer, entry);
765 WARN_ON(!buffer->free);
767 list_del(&buffer->entry);
768 WARN_ON_ONCE(!list_empty(&alloc->buffers));
776 for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
780 if (!alloc->pages[i].page_ptr)
783 on_lru = list_lru_del(&binder_alloc_lru,
784 &alloc->pages[i].lru);
785 page_addr = alloc->buffer + i * PAGE_SIZE;
786 binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
787 "%s: %d: page %d at %pK %s\n",
788 __func__, alloc->pid, i, page_addr,
789 on_lru ? "on lru" : "active");
790 unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE);
791 __free_page(alloc->pages[i].page_ptr);
795 vfree(alloc->buffer);
797 mutex_unlock(&alloc->mutex);
799 binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE,
800 "%s: %d buffers %d, pages %d\n",
801 __func__, alloc->pid, buffers, page_count);
804 static void print_binder_buffer(struct seq_file *m, const char *prefix,
805 struct binder_buffer *buffer)
807 seq_printf(m, "%s %d: %pK size %zd:%zd:%zd %s\n",
808 prefix, buffer->debug_id, buffer->data,
809 buffer->data_size, buffer->offsets_size,
810 buffer->extra_buffers_size,
811 buffer->transaction ? "active" : "delivered");
815 * binder_alloc_print_allocated() - print buffer info
816 * @m: seq_file for output via seq_printf()
817 * @alloc: binder_alloc for this proc
819 * Prints information about every buffer associated with
820 * the binder_alloc state to the given seq_file
822 void binder_alloc_print_allocated(struct seq_file *m,
823 struct binder_alloc *alloc)
827 mutex_lock(&alloc->mutex);
828 for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n))
829 print_binder_buffer(m, " buffer",
830 rb_entry(n, struct binder_buffer, rb_node));
831 mutex_unlock(&alloc->mutex);
835 * binder_alloc_print_pages() - print page usage
836 * @m: seq_file for output via seq_printf()
837 * @alloc: binder_alloc for this proc
839 void binder_alloc_print_pages(struct seq_file *m,
840 struct binder_alloc *alloc)
842 struct binder_lru_page *page;
848 mutex_lock(&alloc->mutex);
849 for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
850 page = &alloc->pages[i];
853 else if (list_empty(&page->lru))
858 mutex_unlock(&alloc->mutex);
859 seq_printf(m, " pages: %d:%d:%d\n", active, lru, free);
863 * binder_alloc_get_allocated_count() - return count of buffers
864 * @alloc: binder_alloc for this proc
866 * Return: count of allocated buffers
868 int binder_alloc_get_allocated_count(struct binder_alloc *alloc)
873 mutex_lock(&alloc->mutex);
874 for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n))
876 mutex_unlock(&alloc->mutex);
882 * binder_alloc_vma_close() - invalidate address space
883 * @alloc: binder_alloc for this proc
885 * Called from binder_vma_close() when releasing address space.
886 * Clears alloc->vma to prevent new incoming transactions from
887 * allocating more buffers.
889 void binder_alloc_vma_close(struct binder_alloc *alloc)
891 WRITE_ONCE(alloc->vma, NULL);
892 WRITE_ONCE(alloc->vma_vm_mm, NULL);
896 * binder_alloc_free_page() - shrinker callback to free pages
897 * @item: item to free
898 * @lock: lock protecting the item
899 * @cb_arg: callback argument
901 * Called from list_lru_walk() in binder_shrink_scan() to free
902 * up pages when the system is under memory pressure.
904 enum lru_status binder_alloc_free_page(struct list_head *item,
905 struct list_lru_one *lru,
909 struct mm_struct *mm = NULL;
910 struct binder_lru_page *page = container_of(item,
911 struct binder_lru_page,
913 struct binder_alloc *alloc;
916 struct vm_area_struct *vma;
919 if (!mutex_trylock(&alloc->mutex))
920 goto err_get_alloc_mutex_failed;
923 goto err_page_already_freed;
925 index = page - alloc->pages;
926 page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE;
929 mm = get_task_mm(alloc->tsk);
931 goto err_get_task_mm_failed;
932 if (!down_write_trylock(&mm->mmap_sem))
933 goto err_down_write_mmap_sem_failed;
936 list_lru_isolate(lru, item);
940 trace_binder_unmap_user_start(alloc, index);
943 page_addr + alloc->user_buffer_offset,
946 trace_binder_unmap_user_end(alloc, index);
948 up_write(&mm->mmap_sem);
952 trace_binder_unmap_kernel_start(alloc, index);
954 unmap_kernel_range(page_addr, PAGE_SIZE);
955 __free_page(page->page_ptr);
956 page->page_ptr = NULL;
958 trace_binder_unmap_kernel_end(alloc, index);
961 mutex_unlock(&alloc->mutex);
962 return LRU_REMOVED_RETRY;
964 err_down_write_mmap_sem_failed:
966 err_get_task_mm_failed:
967 err_page_already_freed:
968 mutex_unlock(&alloc->mutex);
969 err_get_alloc_mutex_failed:
974 binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
976 unsigned long ret = list_lru_count(&binder_alloc_lru);
981 binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
985 ret = list_lru_walk(&binder_alloc_lru, binder_alloc_free_page,
986 NULL, sc->nr_to_scan);
990 struct shrinker binder_shrinker = {
991 .count_objects = binder_shrink_count,
992 .scan_objects = binder_shrink_scan,
993 .seeks = DEFAULT_SEEKS,
997 * binder_alloc_init() - called by binder_open() for per-proc initialization
998 * @alloc: binder_alloc for this proc
1000 * Called from binder_open() to initialize binder_alloc fields for
1003 void binder_alloc_init(struct binder_alloc *alloc)
1005 alloc->tsk = current->group_leader;
1006 alloc->pid = current->group_leader->pid;
1007 mutex_init(&alloc->mutex);
1008 INIT_LIST_HEAD(&alloc->buffers);
1011 void binder_alloc_shrinker_init(void)
1013 list_lru_init(&binder_alloc_lru);
1014 register_shrinker(&binder_shrinker);