diff options
| -rw-r--r-- | drivers/android/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/android/Makefile | 1 | ||||
| -rw-r--r-- | drivers/android/binder.c | 2 | ||||
| -rw-r--r-- | drivers/android/binder_alloc.h | 5 | ||||
| -rw-r--r-- | drivers/android/binder_alloc_selftest.c | 271 |
5 files changed, 289 insertions, 0 deletions
diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig index 8a748d4a4167..9801d852bd56 100644 --- a/drivers/android/Kconfig +++ b/drivers/android/Kconfig @@ -44,6 +44,16 @@ config ANDROID_BINDER_IPC_32BIT Note that enabling this will break newer Android user-space. +config ANDROID_BINDER_IPC_SELFTEST + bool "Android Binder IPC Driver Selftest" + depends on ANDROID_BINDER_IPC + ---help--- + This feature allows binder selftest to run. + + Binder selftest checks the allocation and free of binder buffers + exhaustively with combinations of various buffer sizes and + alignments. + endif # if ANDROID endmenu diff --git a/drivers/android/Makefile b/drivers/android/Makefile index 4b7c726bb560..a01254c43ee3 100644 --- a/drivers/android/Makefile +++ b/drivers/android/Makefile @@ -1,3 +1,4 @@ ccflags-y += -I$(src) # needed for trace events obj-$(CONFIG_ANDROID_BINDER_IPC) += binder.o binder_alloc.o +obj-$(CONFIG_ANDROID_BINDER_IPC_SELFTEST) += binder_alloc_selftest.o diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 947eb7056fa7..e4b6055aafc7 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -4225,6 +4225,8 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) /*pr_info("binder_ioctl: %d:%d %x %lx\n", proc->pid, current->pid, cmd, arg);*/ + binder_selftest_alloc(&proc->alloc); + trace_binder_ioctl(cmd, arg); ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index 088e4ffc6230..4f02cc084c15 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -102,6 +102,11 @@ struct binder_alloc { int pid; }; +#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST +void binder_selftest_alloc(struct binder_alloc *alloc); +#else +static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} +#endif extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, size_t data_size, size_t offsets_size, diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c new file mode 100644 index 000000000000..cc00ab6ee29d --- /dev/null +++ b/drivers/android/binder_alloc_selftest.c @@ -0,0 +1,271 @@ +/* binder_alloc_selftest.c + * + * Android IPC Subsystem + * + * Copyright (C) 2017 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/mm_types.h> +#include <linux/err.h> +#include "binder_alloc.h" + +#define BUFFER_NUM 5 +#define BUFFER_MIN_SIZE (PAGE_SIZE / 8) + +static bool binder_selftest_run = true; +static int binder_selftest_failures; +static DEFINE_MUTEX(binder_selftest_lock); + +/** + * enum buf_end_align_type - Page alignment of a buffer + * end with regard to the end of the previous buffer. + * + * In the pictures below, buf2 refers to the buffer we + * are aligning. buf1 refers to previous buffer by addr. + * Symbol [ means the start of a buffer, ] means the end + * of a buffer, and | means page boundaries. + */ +enum buf_end_align_type { + /** + * @SAME_PAGE_UNALIGNED: The end of this buffer is on + * the same page as the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 ][ ... + * buf1 ]|[ buf2 ][ ... + */ + SAME_PAGE_UNALIGNED = 0, + /** + * @SAME_PAGE_ALIGNED: When the end of the previous buffer + * is not page aligned, the end of this buffer is on the + * same page as the end of the previous buffer and is page + * aligned. When the previous buffer is page aligned, the + * end of this buffer is aligned to the next page boundary. + * Examples: + * buf1 ][ buf2 ]| ... + * buf1 ]|[ buf2 ]| ... + */ + SAME_PAGE_ALIGNED, + /** + * @NEXT_PAGE_UNALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 ][ ... + */ + NEXT_PAGE_UNALIGNED, + /** + * @NEXT_PAGE_ALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is page aligned. Examples: + * buf1 ][ buf2 | buf2 ]| ... + * buf1 ]|[ buf2 | buf2 ]| ... + */ + NEXT_PAGE_ALIGNED, + /** + * @NEXT_NEXT_UNALIGNED: The end of this buffer is on + * the page that follows the page after the end of the + * previous buffer and is not page aligned. Examples: + * buf1 ][ buf2 | buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 | buf2 ][ ... + */ + NEXT_NEXT_UNALIGNED, + LOOP_END, +}; + +static void pr_err_size_seq(size_t *sizes, int *seq) +{ + int i; + + pr_err("alloc sizes: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%zu]", sizes[i]); + pr_cont("\n"); + pr_err("free seq: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%d]", seq[i]); + pr_cont("\n"); +} + +static bool check_buffer_pages_allocated(struct binder_alloc *alloc, + struct binder_buffer *buffer, + size_t size) +{ + void *page_addr, *end; + int page_index; + + end = (void *)PAGE_ALIGN((uintptr_t)buffer + size); + for (page_addr = buffer; page_addr < end; page_addr += PAGE_SIZE) { + page_index = (page_addr - alloc->buffer) / PAGE_SIZE; + if (!alloc->pages[page_index]) { + pr_err("incorrect alloc state at page index %d\n", + page_index); + return false; + } + } + return true; +} + +static void binder_selftest_alloc_buf(struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) { + buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0); + if (IS_ERR(buffers[i]) || + !check_buffer_pages_allocated(alloc, buffers[i], + sizes[i])) { + pr_err_size_seq(sizes, seq); + binder_selftest_failures++; + } + } +} + +static void binder_selftest_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) + binder_alloc_free_buf(alloc, buffers[seq[i]]); + + for (i = 0; i < (alloc->buffer_size / PAGE_SIZE); i++) { + if ((!alloc->pages[i]) == (i == 0)) { + pr_err("incorrect free state at page index %d\n", i); + binder_selftest_failures++; + } + } +} + +static void binder_selftest_alloc_free(struct binder_alloc *alloc, + size_t *sizes, int *seq) +{ + struct binder_buffer *buffers[BUFFER_NUM]; + + binder_selftest_alloc_buf(alloc, buffers, sizes, seq); + binder_selftest_free_buf(alloc, buffers, sizes, seq); +} + +static bool is_dup(int *seq, int index, int val) +{ + int i; + + for (i = 0; i < index; i++) { + if (seq[i] == val) + return true; + } + return false; +} + +/* Generate BUFFER_NUM factorial free orders. */ +static void binder_selftest_free_seq(struct binder_alloc *alloc, + size_t *sizes, int *seq, int index) +{ + int i; + + if (index == BUFFER_NUM) { + binder_selftest_alloc_free(alloc, sizes, seq); + return; + } + for (i = 0; i < BUFFER_NUM; i++) { + if (is_dup(seq, index, i)) + continue; + seq[index] = i; + binder_selftest_free_seq(alloc, sizes, seq, index + 1); + } +} + +static void binder_selftest_alloc_size(struct binder_alloc *alloc, + size_t *end_offset) +{ + int i; + int seq[BUFFER_NUM] = {0}; + size_t front_sizes[BUFFER_NUM]; + size_t back_sizes[BUFFER_NUM]; + size_t last_offset, offset = 0; + + for (i = 0; i < BUFFER_NUM; i++) { + last_offset = offset; + offset = end_offset[i]; + front_sizes[i] = offset - last_offset; + back_sizes[BUFFER_NUM - i - 1] = front_sizes[i]; + } + /* + * Buffers share the first or last few pages. + * Only BUFFER_NUM - 1 buffer sizes are adjustable since + * we need one giant buffer before getting to the last page. + */ + back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1] + - sizeof(struct binder_buffer) * BUFFER_NUM; + binder_selftest_free_seq(alloc, front_sizes, seq, 0); + binder_selftest_free_seq(alloc, back_sizes, seq, 0); +} + +static void binder_selftest_alloc_offset(struct binder_alloc *alloc, + size_t *end_offset, int index) +{ + int align; + size_t end, prev; + + if (index == BUFFER_NUM) { + binder_selftest_alloc_size(alloc, end_offset); + return; + } + prev = index == 0 ? 0 : end_offset[index - 1]; + end = prev; + + BUILD_BUG_ON((BUFFER_MIN_SIZE + sizeof(struct binder_buffer)) + * BUFFER_NUM >= PAGE_SIZE); + + for (align = SAME_PAGE_UNALIGNED; align < LOOP_END; align++) { + if (align % 2) + end = ALIGN(end, PAGE_SIZE); + else + end += BUFFER_MIN_SIZE; + end_offset[index] = end; + binder_selftest_alloc_offset(alloc, end_offset, index + 1); + } +} + +/** + * binder_selftest_alloc() - Test alloc and free of buffer pages. + * @alloc: Pointer to alloc struct. + * + * Allocate BUFFER_NUM buffers to cover all page alignment cases, + * then free them in all orders possible. Check that pages are + * allocated after buffer alloc and freed after freeing buffer. + */ +void binder_selftest_alloc(struct binder_alloc *alloc) +{ + size_t end_offset[BUFFER_NUM]; + + if (!binder_selftest_run) + return; + mutex_lock(&binder_selftest_lock); + if (!binder_selftest_run || !alloc->vma) + goto done; + pr_info("STARTED\n"); + binder_selftest_alloc_offset(alloc, end_offset, 0); + binder_selftest_run = false; + if (binder_selftest_failures > 0) + pr_info("%d tests FAILED\n", binder_selftest_failures); + else + pr_info("PASSED\n"); + +done: + mutex_unlock(&binder_selftest_lock); +} |