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296455ade1
Here is the big set of char/misc and other driver subsystem changes for 6.8-rc1. Lots of stuff in here, but first off, you will get a merge conflict in drivers/android/binder_alloc.c when merging this tree due to changing coming in through the -mm tree. The resolution of the merge issue can be found here: https://lore.kernel.org/r/20231207134213.25631ae9@canb.auug.org.au or in a simpler patch form in that thread: https://lore.kernel.org/r/ZXHzooF07LfQQYiE@google.com If there are issues with the merge of this file, please let me know. Other than lots of binder driver changes (as you can see by the merge conflicts) included in here are: - lots of iio driver updates and additions - spmi driver updates - eeprom driver updates - firmware driver updates - ocxl driver updates - mhi driver updates - w1 driver updates - nvmem driver updates - coresight driver updates - platform driver remove callback api changes - tags.sh script updates - bus_type constant marking cleanups - lots of other small driver updates All of these have been in linux-next for a while with no reported issues (other than the binder merge conflict.) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> -----BEGIN PGP SIGNATURE----- iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZaeMMQ8cZ3JlZ0Brcm9h aC5jb20ACgkQMUfUDdst+ynWNgCfQ/Yz7QO6EMLDwHO5LRsb3YMhjL4AoNVdanjP YoI7f1I4GBcC0GKNfK6s =+Kyv -----END PGP SIGNATURE----- Merge tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver updates from Greg KH: "Here is the big set of char/misc and other driver subsystem changes for 6.8-rc1. Other than lots of binder driver changes (as you can see by the merge conflicts) included in here are: - lots of iio driver updates and additions - spmi driver updates - eeprom driver updates - firmware driver updates - ocxl driver updates - mhi driver updates - w1 driver updates - nvmem driver updates - coresight driver updates - platform driver remove callback api changes - tags.sh script updates - bus_type constant marking cleanups - lots of other small driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (341 commits) android: removed duplicate linux/errno uio: Fix use-after-free in uio_open drivers: soc: xilinx: add check for platform firmware: xilinx: Export function to use in other module scripts/tags.sh: remove find_sources scripts/tags.sh: use -n to test archinclude scripts/tags.sh: add local annotation scripts/tags.sh: use more portable -path instead of -wholename scripts/tags.sh: Update comment (addition of gtags) firmware: zynqmp: Convert to platform remove callback returning void firmware: turris-mox-rwtm: Convert to platform remove callback returning void firmware: stratix10-svc: Convert to platform remove callback returning void firmware: stratix10-rsu: Convert to platform remove callback returning void firmware: raspberrypi: Convert to platform remove callback returning void firmware: qemu_fw_cfg: Convert to platform remove callback returning void firmware: mtk-adsp-ipc: Convert to platform remove callback returning void firmware: imx-dsp: Convert to platform remove callback returning void firmware: coreboot_table: Convert to platform remove callback returning void firmware: arm_scpi: Convert to platform remove callback returning void firmware: arm_scmi: Convert to platform remove callback returning void ...
1310 lines
35 KiB
C
1310 lines
35 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/* binder_alloc.c
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*
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* Android IPC Subsystem
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*
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* Copyright (C) 2007-2017 Google, Inc.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/list.h>
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#include <linux/sched/mm.h>
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#include <linux/module.h>
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#include <linux/rtmutex.h>
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#include <linux/rbtree.h>
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#include <linux/seq_file.h>
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#include <linux/vmalloc.h>
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#include <linux/slab.h>
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#include <linux/sched.h>
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#include <linux/list_lru.h>
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#include <linux/ratelimit.h>
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#include <asm/cacheflush.h>
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#include <linux/uaccess.h>
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#include <linux/highmem.h>
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#include <linux/sizes.h>
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#include "binder_alloc.h"
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#include "binder_trace.h"
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struct list_lru binder_freelist;
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static DEFINE_MUTEX(binder_alloc_mmap_lock);
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enum {
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BINDER_DEBUG_USER_ERROR = 1U << 0,
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BINDER_DEBUG_OPEN_CLOSE = 1U << 1,
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BINDER_DEBUG_BUFFER_ALLOC = 1U << 2,
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BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 3,
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};
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static uint32_t binder_alloc_debug_mask = BINDER_DEBUG_USER_ERROR;
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module_param_named(debug_mask, binder_alloc_debug_mask,
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uint, 0644);
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#define binder_alloc_debug(mask, x...) \
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do { \
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if (binder_alloc_debug_mask & mask) \
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pr_info_ratelimited(x); \
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} while (0)
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static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer)
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{
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return list_entry(buffer->entry.next, struct binder_buffer, entry);
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}
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static struct binder_buffer *binder_buffer_prev(struct binder_buffer *buffer)
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{
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return list_entry(buffer->entry.prev, struct binder_buffer, entry);
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}
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static size_t binder_alloc_buffer_size(struct binder_alloc *alloc,
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struct binder_buffer *buffer)
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{
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if (list_is_last(&buffer->entry, &alloc->buffers))
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return alloc->buffer + alloc->buffer_size - buffer->user_data;
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return binder_buffer_next(buffer)->user_data - buffer->user_data;
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}
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static void binder_insert_free_buffer(struct binder_alloc *alloc,
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struct binder_buffer *new_buffer)
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{
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struct rb_node **p = &alloc->free_buffers.rb_node;
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struct rb_node *parent = NULL;
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struct binder_buffer *buffer;
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size_t buffer_size;
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size_t new_buffer_size;
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BUG_ON(!new_buffer->free);
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new_buffer_size = binder_alloc_buffer_size(alloc, new_buffer);
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binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
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"%d: add free buffer, size %zd, at %pK\n",
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alloc->pid, new_buffer_size, new_buffer);
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while (*p) {
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parent = *p;
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buffer = rb_entry(parent, struct binder_buffer, rb_node);
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BUG_ON(!buffer->free);
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buffer_size = binder_alloc_buffer_size(alloc, buffer);
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if (new_buffer_size < buffer_size)
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p = &parent->rb_left;
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else
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p = &parent->rb_right;
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}
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rb_link_node(&new_buffer->rb_node, parent, p);
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rb_insert_color(&new_buffer->rb_node, &alloc->free_buffers);
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}
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static void binder_insert_allocated_buffer_locked(
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struct binder_alloc *alloc, struct binder_buffer *new_buffer)
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{
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struct rb_node **p = &alloc->allocated_buffers.rb_node;
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struct rb_node *parent = NULL;
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struct binder_buffer *buffer;
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BUG_ON(new_buffer->free);
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while (*p) {
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parent = *p;
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buffer = rb_entry(parent, struct binder_buffer, rb_node);
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BUG_ON(buffer->free);
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if (new_buffer->user_data < buffer->user_data)
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p = &parent->rb_left;
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else if (new_buffer->user_data > buffer->user_data)
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p = &parent->rb_right;
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else
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BUG();
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}
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rb_link_node(&new_buffer->rb_node, parent, p);
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rb_insert_color(&new_buffer->rb_node, &alloc->allocated_buffers);
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}
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static struct binder_buffer *binder_alloc_prepare_to_free_locked(
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struct binder_alloc *alloc,
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unsigned long user_ptr)
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{
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struct rb_node *n = alloc->allocated_buffers.rb_node;
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struct binder_buffer *buffer;
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while (n) {
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buffer = rb_entry(n, struct binder_buffer, rb_node);
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BUG_ON(buffer->free);
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if (user_ptr < buffer->user_data) {
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n = n->rb_left;
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} else if (user_ptr > buffer->user_data) {
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n = n->rb_right;
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} else {
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/*
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* Guard against user threads attempting to
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* free the buffer when in use by kernel or
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* after it's already been freed.
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*/
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if (!buffer->allow_user_free)
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return ERR_PTR(-EPERM);
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buffer->allow_user_free = 0;
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return buffer;
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}
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}
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return NULL;
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}
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/**
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* binder_alloc_prepare_to_free() - get buffer given user ptr
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* @alloc: binder_alloc for this proc
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* @user_ptr: User pointer to buffer data
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*
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* Validate userspace pointer to buffer data and return buffer corresponding to
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* that user pointer. Search the rb tree for buffer that matches user data
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* pointer.
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*
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* Return: Pointer to buffer or NULL
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*/
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struct binder_buffer *binder_alloc_prepare_to_free(struct binder_alloc *alloc,
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unsigned long user_ptr)
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{
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struct binder_buffer *buffer;
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spin_lock(&alloc->lock);
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buffer = binder_alloc_prepare_to_free_locked(alloc, user_ptr);
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spin_unlock(&alloc->lock);
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return buffer;
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}
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static inline void
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binder_set_installed_page(struct binder_lru_page *lru_page,
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struct page *page)
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{
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/* Pairs with acquire in binder_get_installed_page() */
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smp_store_release(&lru_page->page_ptr, page);
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}
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static inline struct page *
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binder_get_installed_page(struct binder_lru_page *lru_page)
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{
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/* Pairs with release in binder_set_installed_page() */
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return smp_load_acquire(&lru_page->page_ptr);
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}
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static void binder_lru_freelist_add(struct binder_alloc *alloc,
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unsigned long start, unsigned long end)
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{
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struct binder_lru_page *page;
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unsigned long page_addr;
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trace_binder_update_page_range(alloc, false, start, end);
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for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) {
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size_t index;
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int ret;
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index = (page_addr - alloc->buffer) / PAGE_SIZE;
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page = &alloc->pages[index];
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if (!binder_get_installed_page(page))
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continue;
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trace_binder_free_lru_start(alloc, index);
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ret = list_lru_add_obj(&binder_freelist, &page->lru);
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WARN_ON(!ret);
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trace_binder_free_lru_end(alloc, index);
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}
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}
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static int binder_install_single_page(struct binder_alloc *alloc,
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struct binder_lru_page *lru_page,
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unsigned long addr)
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{
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struct page *page;
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int ret = 0;
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if (!mmget_not_zero(alloc->mm))
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return -ESRCH;
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/*
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* Protected with mmap_sem in write mode as multiple tasks
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* might race to install the same page.
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*/
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mmap_write_lock(alloc->mm);
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if (binder_get_installed_page(lru_page))
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goto out;
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if (!alloc->vma) {
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pr_err("%d: %s failed, no vma\n", alloc->pid, __func__);
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ret = -ESRCH;
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goto out;
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}
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page = alloc_page(GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
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if (!page) {
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pr_err("%d: failed to allocate page\n", alloc->pid);
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ret = -ENOMEM;
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goto out;
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}
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ret = vm_insert_page(alloc->vma, addr, page);
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if (ret) {
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pr_err("%d: %s failed to insert page at offset %lx with %d\n",
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alloc->pid, __func__, addr - alloc->buffer, ret);
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__free_page(page);
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ret = -ENOMEM;
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goto out;
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}
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/* Mark page installation complete and safe to use */
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binder_set_installed_page(lru_page, page);
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out:
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mmap_write_unlock(alloc->mm);
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mmput_async(alloc->mm);
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return ret;
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}
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static int binder_install_buffer_pages(struct binder_alloc *alloc,
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struct binder_buffer *buffer,
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size_t size)
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{
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struct binder_lru_page *page;
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unsigned long start, final;
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unsigned long page_addr;
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start = buffer->user_data & PAGE_MASK;
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final = PAGE_ALIGN(buffer->user_data + size);
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for (page_addr = start; page_addr < final; page_addr += PAGE_SIZE) {
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unsigned long index;
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int ret;
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index = (page_addr - alloc->buffer) / PAGE_SIZE;
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page = &alloc->pages[index];
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if (binder_get_installed_page(page))
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continue;
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trace_binder_alloc_page_start(alloc, index);
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ret = binder_install_single_page(alloc, page, page_addr);
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if (ret)
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return ret;
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trace_binder_alloc_page_end(alloc, index);
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}
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return 0;
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}
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/* The range of pages should exclude those shared with other buffers */
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static void binder_lru_freelist_del(struct binder_alloc *alloc,
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unsigned long start, unsigned long end)
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{
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struct binder_lru_page *page;
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unsigned long page_addr;
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trace_binder_update_page_range(alloc, true, start, end);
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for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) {
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unsigned long index;
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bool on_lru;
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index = (page_addr - alloc->buffer) / PAGE_SIZE;
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page = &alloc->pages[index];
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if (page->page_ptr) {
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trace_binder_alloc_lru_start(alloc, index);
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on_lru = list_lru_del_obj(&binder_freelist, &page->lru);
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WARN_ON(!on_lru);
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trace_binder_alloc_lru_end(alloc, index);
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continue;
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}
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if (index + 1 > alloc->pages_high)
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alloc->pages_high = index + 1;
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}
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}
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static inline void binder_alloc_set_vma(struct binder_alloc *alloc,
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struct vm_area_struct *vma)
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{
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/* pairs with smp_load_acquire in binder_alloc_get_vma() */
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smp_store_release(&alloc->vma, vma);
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}
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static inline struct vm_area_struct *binder_alloc_get_vma(
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struct binder_alloc *alloc)
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{
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/* pairs with smp_store_release in binder_alloc_set_vma() */
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return smp_load_acquire(&alloc->vma);
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}
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static void debug_no_space_locked(struct binder_alloc *alloc)
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{
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size_t largest_alloc_size = 0;
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struct binder_buffer *buffer;
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size_t allocated_buffers = 0;
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size_t largest_free_size = 0;
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size_t total_alloc_size = 0;
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size_t total_free_size = 0;
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size_t free_buffers = 0;
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size_t buffer_size;
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struct rb_node *n;
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for (n = rb_first(&alloc->allocated_buffers); n; n = rb_next(n)) {
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buffer = rb_entry(n, struct binder_buffer, rb_node);
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buffer_size = binder_alloc_buffer_size(alloc, buffer);
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allocated_buffers++;
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total_alloc_size += buffer_size;
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if (buffer_size > largest_alloc_size)
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largest_alloc_size = buffer_size;
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}
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for (n = rb_first(&alloc->free_buffers); n; n = rb_next(n)) {
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buffer = rb_entry(n, struct binder_buffer, rb_node);
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buffer_size = binder_alloc_buffer_size(alloc, buffer);
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free_buffers++;
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total_free_size += buffer_size;
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if (buffer_size > largest_free_size)
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largest_free_size = buffer_size;
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}
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binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
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"allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
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total_alloc_size, allocated_buffers,
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largest_alloc_size, total_free_size,
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free_buffers, largest_free_size);
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}
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static bool debug_low_async_space_locked(struct binder_alloc *alloc)
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{
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/*
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* Find the amount and size of buffers allocated by the current caller;
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* The idea is that once we cross the threshold, whoever is responsible
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* for the low async space is likely to try to send another async txn,
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* and at some point we'll catch them in the act. This is more efficient
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* than keeping a map per pid.
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*/
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struct binder_buffer *buffer;
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size_t total_alloc_size = 0;
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int pid = current->tgid;
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size_t num_buffers = 0;
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struct rb_node *n;
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/*
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* Only start detecting spammers once we have less than 20% of async
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* space left (which is less than 10% of total buffer size).
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*/
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if (alloc->free_async_space >= alloc->buffer_size / 10) {
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alloc->oneway_spam_detected = false;
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return false;
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}
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for (n = rb_first(&alloc->allocated_buffers); n != NULL;
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n = rb_next(n)) {
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buffer = rb_entry(n, struct binder_buffer, rb_node);
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if (buffer->pid != pid)
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continue;
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if (!buffer->async_transaction)
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continue;
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total_alloc_size += binder_alloc_buffer_size(alloc, buffer);
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num_buffers++;
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}
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/*
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* Warn if this pid has more than 50 transactions, or more than 50% of
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* async space (which is 25% of total buffer size). Oneway spam is only
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* detected when the threshold is exceeded.
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*/
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if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) {
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binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
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"%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n",
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alloc->pid, pid, num_buffers, total_alloc_size);
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if (!alloc->oneway_spam_detected) {
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alloc->oneway_spam_detected = true;
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return true;
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}
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}
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return false;
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}
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|
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/* Callers preallocate @new_buffer, it is freed by this function if unused */
|
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static struct binder_buffer *binder_alloc_new_buf_locked(
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struct binder_alloc *alloc,
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struct binder_buffer *new_buffer,
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size_t size,
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int is_async)
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{
|
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struct rb_node *n = alloc->free_buffers.rb_node;
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struct rb_node *best_fit = NULL;
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struct binder_buffer *buffer;
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unsigned long next_used_page;
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unsigned long curr_last_page;
|
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size_t buffer_size;
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|
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if (is_async && alloc->free_async_space < size) {
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binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
|
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"%d: binder_alloc_buf size %zd failed, no async space left\n",
|
|
alloc->pid, size);
|
|
buffer = ERR_PTR(-ENOSPC);
|
|
goto out;
|
|
}
|
|
|
|
while (n) {
|
|
buffer = rb_entry(n, struct binder_buffer, rb_node);
|
|
BUG_ON(!buffer->free);
|
|
buffer_size = binder_alloc_buffer_size(alloc, buffer);
|
|
|
|
if (size < buffer_size) {
|
|
best_fit = n;
|
|
n = n->rb_left;
|
|
} else if (size > buffer_size) {
|
|
n = n->rb_right;
|
|
} else {
|
|
best_fit = n;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (unlikely(!best_fit)) {
|
|
binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
|
|
"%d: binder_alloc_buf size %zd failed, no address space\n",
|
|
alloc->pid, size);
|
|
debug_no_space_locked(alloc);
|
|
buffer = ERR_PTR(-ENOSPC);
|
|
goto out;
|
|
}
|
|
|
|
if (buffer_size != size) {
|
|
/* Found an oversized buffer and needs to be split */
|
|
buffer = rb_entry(best_fit, struct binder_buffer, rb_node);
|
|
buffer_size = binder_alloc_buffer_size(alloc, buffer);
|
|
|
|
WARN_ON(n || buffer_size == size);
|
|
new_buffer->user_data = buffer->user_data + size;
|
|
list_add(&new_buffer->entry, &buffer->entry);
|
|
new_buffer->free = 1;
|
|
binder_insert_free_buffer(alloc, new_buffer);
|
|
new_buffer = NULL;
|
|
}
|
|
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
|
|
"%d: binder_alloc_buf size %zd got buffer %pK size %zd\n",
|
|
alloc->pid, size, buffer, buffer_size);
|
|
|
|
/*
|
|
* Now we remove the pages from the freelist. A clever calculation
|
|
* with buffer_size determines if the last page is shared with an
|
|
* adjacent in-use buffer. In such case, the page has been already
|
|
* removed from the freelist so we trim our range short.
|
|
*/
|
|
next_used_page = (buffer->user_data + buffer_size) & PAGE_MASK;
|
|
curr_last_page = PAGE_ALIGN(buffer->user_data + size);
|
|
binder_lru_freelist_del(alloc, PAGE_ALIGN(buffer->user_data),
|
|
min(next_used_page, curr_last_page));
|
|
|
|
rb_erase(&buffer->rb_node, &alloc->free_buffers);
|
|
buffer->free = 0;
|
|
buffer->allow_user_free = 0;
|
|
binder_insert_allocated_buffer_locked(alloc, buffer);
|
|
buffer->async_transaction = is_async;
|
|
buffer->oneway_spam_suspect = false;
|
|
if (is_async) {
|
|
alloc->free_async_space -= size;
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
|
|
"%d: binder_alloc_buf size %zd async free %zd\n",
|
|
alloc->pid, size, alloc->free_async_space);
|
|
if (debug_low_async_space_locked(alloc))
|
|
buffer->oneway_spam_suspect = true;
|
|
}
|
|
|
|
out:
|
|
/* Discard possibly unused new_buffer */
|
|
kfree(new_buffer);
|
|
return buffer;
|
|
}
|
|
|
|
/* Calculate the sanitized total size, returns 0 for invalid request */
|
|
static inline size_t sanitized_size(size_t data_size,
|
|
size_t offsets_size,
|
|
size_t extra_buffers_size)
|
|
{
|
|
size_t total, tmp;
|
|
|
|
/* Align to pointer size and check for overflows */
|
|
tmp = ALIGN(data_size, sizeof(void *)) +
|
|
ALIGN(offsets_size, sizeof(void *));
|
|
if (tmp < data_size || tmp < offsets_size)
|
|
return 0;
|
|
total = tmp + ALIGN(extra_buffers_size, sizeof(void *));
|
|
if (total < tmp || total < extra_buffers_size)
|
|
return 0;
|
|
|
|
/* Pad 0-sized buffers so they get a unique address */
|
|
total = max(total, sizeof(void *));
|
|
|
|
return total;
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_new_buf() - Allocate a new binder buffer
|
|
* @alloc: binder_alloc for this proc
|
|
* @data_size: size of user data buffer
|
|
* @offsets_size: user specified buffer offset
|
|
* @extra_buffers_size: size of extra space for meta-data (eg, security context)
|
|
* @is_async: buffer for async transaction
|
|
*
|
|
* Allocate a new buffer given the requested sizes. Returns
|
|
* the kernel version of the buffer pointer. The size allocated
|
|
* is the sum of the three given sizes (each rounded up to
|
|
* pointer-sized boundary)
|
|
*
|
|
* Return: The allocated buffer or %ERR_PTR(-errno) if error
|
|
*/
|
|
struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc,
|
|
size_t data_size,
|
|
size_t offsets_size,
|
|
size_t extra_buffers_size,
|
|
int is_async)
|
|
{
|
|
struct binder_buffer *buffer, *next;
|
|
size_t size;
|
|
int ret;
|
|
|
|
/* Check binder_alloc is fully initialized */
|
|
if (!binder_alloc_get_vma(alloc)) {
|
|
binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
|
|
"%d: binder_alloc_buf, no vma\n",
|
|
alloc->pid);
|
|
return ERR_PTR(-ESRCH);
|
|
}
|
|
|
|
size = sanitized_size(data_size, offsets_size, extra_buffers_size);
|
|
if (unlikely(!size)) {
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
|
|
"%d: got transaction with invalid size %zd-%zd-%zd\n",
|
|
alloc->pid, data_size, offsets_size,
|
|
extra_buffers_size);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
/* Preallocate the next buffer */
|
|
next = kzalloc(sizeof(*next), GFP_KERNEL);
|
|
if (!next)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
spin_lock(&alloc->lock);
|
|
buffer = binder_alloc_new_buf_locked(alloc, next, size, is_async);
|
|
if (IS_ERR(buffer)) {
|
|
spin_unlock(&alloc->lock);
|
|
goto out;
|
|
}
|
|
|
|
buffer->data_size = data_size;
|
|
buffer->offsets_size = offsets_size;
|
|
buffer->extra_buffers_size = extra_buffers_size;
|
|
buffer->pid = current->tgid;
|
|
spin_unlock(&alloc->lock);
|
|
|
|
ret = binder_install_buffer_pages(alloc, buffer, size);
|
|
if (ret) {
|
|
binder_alloc_free_buf(alloc, buffer);
|
|
buffer = ERR_PTR(ret);
|
|
}
|
|
out:
|
|
return buffer;
|
|
}
|
|
|
|
static unsigned long buffer_start_page(struct binder_buffer *buffer)
|
|
{
|
|
return buffer->user_data & PAGE_MASK;
|
|
}
|
|
|
|
static unsigned long prev_buffer_end_page(struct binder_buffer *buffer)
|
|
{
|
|
return (buffer->user_data - 1) & PAGE_MASK;
|
|
}
|
|
|
|
static void binder_delete_free_buffer(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer)
|
|
{
|
|
struct binder_buffer *prev, *next;
|
|
|
|
if (PAGE_ALIGNED(buffer->user_data))
|
|
goto skip_freelist;
|
|
|
|
BUG_ON(alloc->buffers.next == &buffer->entry);
|
|
prev = binder_buffer_prev(buffer);
|
|
BUG_ON(!prev->free);
|
|
if (prev_buffer_end_page(prev) == buffer_start_page(buffer))
|
|
goto skip_freelist;
|
|
|
|
if (!list_is_last(&buffer->entry, &alloc->buffers)) {
|
|
next = binder_buffer_next(buffer);
|
|
if (buffer_start_page(next) == buffer_start_page(buffer))
|
|
goto skip_freelist;
|
|
}
|
|
|
|
binder_lru_freelist_add(alloc, buffer_start_page(buffer),
|
|
buffer_start_page(buffer) + PAGE_SIZE);
|
|
skip_freelist:
|
|
list_del(&buffer->entry);
|
|
kfree(buffer);
|
|
}
|
|
|
|
static void binder_free_buf_locked(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer)
|
|
{
|
|
size_t size, buffer_size;
|
|
|
|
buffer_size = binder_alloc_buffer_size(alloc, buffer);
|
|
|
|
size = ALIGN(buffer->data_size, sizeof(void *)) +
|
|
ALIGN(buffer->offsets_size, sizeof(void *)) +
|
|
ALIGN(buffer->extra_buffers_size, sizeof(void *));
|
|
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
|
|
"%d: binder_free_buf %pK size %zd buffer_size %zd\n",
|
|
alloc->pid, buffer, size, buffer_size);
|
|
|
|
BUG_ON(buffer->free);
|
|
BUG_ON(size > buffer_size);
|
|
BUG_ON(buffer->transaction != NULL);
|
|
BUG_ON(buffer->user_data < alloc->buffer);
|
|
BUG_ON(buffer->user_data > alloc->buffer + alloc->buffer_size);
|
|
|
|
if (buffer->async_transaction) {
|
|
alloc->free_async_space += buffer_size;
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC,
|
|
"%d: binder_free_buf size %zd async free %zd\n",
|
|
alloc->pid, size, alloc->free_async_space);
|
|
}
|
|
|
|
binder_lru_freelist_add(alloc, PAGE_ALIGN(buffer->user_data),
|
|
(buffer->user_data + buffer_size) & PAGE_MASK);
|
|
|
|
rb_erase(&buffer->rb_node, &alloc->allocated_buffers);
|
|
buffer->free = 1;
|
|
if (!list_is_last(&buffer->entry, &alloc->buffers)) {
|
|
struct binder_buffer *next = binder_buffer_next(buffer);
|
|
|
|
if (next->free) {
|
|
rb_erase(&next->rb_node, &alloc->free_buffers);
|
|
binder_delete_free_buffer(alloc, next);
|
|
}
|
|
}
|
|
if (alloc->buffers.next != &buffer->entry) {
|
|
struct binder_buffer *prev = binder_buffer_prev(buffer);
|
|
|
|
if (prev->free) {
|
|
binder_delete_free_buffer(alloc, buffer);
|
|
rb_erase(&prev->rb_node, &alloc->free_buffers);
|
|
buffer = prev;
|
|
}
|
|
}
|
|
binder_insert_free_buffer(alloc, buffer);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_get_page() - get kernel pointer for given buffer offset
|
|
* @alloc: binder_alloc for this proc
|
|
* @buffer: binder buffer to be accessed
|
|
* @buffer_offset: offset into @buffer data
|
|
* @pgoffp: address to copy final page offset to
|
|
*
|
|
* Lookup the struct page corresponding to the address
|
|
* at @buffer_offset into @buffer->user_data. If @pgoffp is not
|
|
* NULL, the byte-offset into the page is written there.
|
|
*
|
|
* The caller is responsible to ensure that the offset points
|
|
* to a valid address within the @buffer and that @buffer is
|
|
* not freeable by the user. Since it can't be freed, we are
|
|
* guaranteed that the corresponding elements of @alloc->pages[]
|
|
* cannot change.
|
|
*
|
|
* Return: struct page
|
|
*/
|
|
static struct page *binder_alloc_get_page(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t buffer_offset,
|
|
pgoff_t *pgoffp)
|
|
{
|
|
binder_size_t buffer_space_offset = buffer_offset +
|
|
(buffer->user_data - alloc->buffer);
|
|
pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK;
|
|
size_t index = buffer_space_offset >> PAGE_SHIFT;
|
|
struct binder_lru_page *lru_page;
|
|
|
|
lru_page = &alloc->pages[index];
|
|
*pgoffp = pgoff;
|
|
return lru_page->page_ptr;
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_clear_buf() - zero out buffer
|
|
* @alloc: binder_alloc for this proc
|
|
* @buffer: binder buffer to be cleared
|
|
*
|
|
* memset the given buffer to 0
|
|
*/
|
|
static void binder_alloc_clear_buf(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer)
|
|
{
|
|
size_t bytes = binder_alloc_buffer_size(alloc, buffer);
|
|
binder_size_t buffer_offset = 0;
|
|
|
|
while (bytes) {
|
|
unsigned long size;
|
|
struct page *page;
|
|
pgoff_t pgoff;
|
|
|
|
page = binder_alloc_get_page(alloc, buffer,
|
|
buffer_offset, &pgoff);
|
|
size = min_t(size_t, bytes, PAGE_SIZE - pgoff);
|
|
memset_page(page, pgoff, 0, size);
|
|
bytes -= size;
|
|
buffer_offset += size;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_free_buf() - free a binder buffer
|
|
* @alloc: binder_alloc for this proc
|
|
* @buffer: kernel pointer to buffer
|
|
*
|
|
* Free the buffer allocated via binder_alloc_new_buf()
|
|
*/
|
|
void binder_alloc_free_buf(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer)
|
|
{
|
|
/*
|
|
* We could eliminate the call to binder_alloc_clear_buf()
|
|
* from binder_alloc_deferred_release() by moving this to
|
|
* binder_free_buf_locked(). However, that could
|
|
* increase contention for the alloc->lock if clear_on_free
|
|
* is used frequently for large buffers. This lock is not
|
|
* needed for correctness here.
|
|
*/
|
|
if (buffer->clear_on_free) {
|
|
binder_alloc_clear_buf(alloc, buffer);
|
|
buffer->clear_on_free = false;
|
|
}
|
|
spin_lock(&alloc->lock);
|
|
binder_free_buf_locked(alloc, buffer);
|
|
spin_unlock(&alloc->lock);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_mmap_handler() - map virtual address space for proc
|
|
* @alloc: alloc structure for this proc
|
|
* @vma: vma passed to mmap()
|
|
*
|
|
* Called by binder_mmap() to initialize the space specified in
|
|
* vma for allocating binder buffers
|
|
*
|
|
* Return:
|
|
* 0 = success
|
|
* -EBUSY = address space already mapped
|
|
* -ENOMEM = failed to map memory to given address space
|
|
*/
|
|
int binder_alloc_mmap_handler(struct binder_alloc *alloc,
|
|
struct vm_area_struct *vma)
|
|
{
|
|
struct binder_buffer *buffer;
|
|
const char *failure_string;
|
|
int ret, i;
|
|
|
|
if (unlikely(vma->vm_mm != alloc->mm)) {
|
|
ret = -EINVAL;
|
|
failure_string = "invalid vma->vm_mm";
|
|
goto err_invalid_mm;
|
|
}
|
|
|
|
mutex_lock(&binder_alloc_mmap_lock);
|
|
if (alloc->buffer_size) {
|
|
ret = -EBUSY;
|
|
failure_string = "already mapped";
|
|
goto err_already_mapped;
|
|
}
|
|
alloc->buffer_size = min_t(unsigned long, vma->vm_end - vma->vm_start,
|
|
SZ_4M);
|
|
mutex_unlock(&binder_alloc_mmap_lock);
|
|
|
|
alloc->buffer = vma->vm_start;
|
|
|
|
alloc->pages = kcalloc(alloc->buffer_size / PAGE_SIZE,
|
|
sizeof(alloc->pages[0]),
|
|
GFP_KERNEL);
|
|
if (alloc->pages == NULL) {
|
|
ret = -ENOMEM;
|
|
failure_string = "alloc page array";
|
|
goto err_alloc_pages_failed;
|
|
}
|
|
|
|
for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
|
|
alloc->pages[i].alloc = alloc;
|
|
INIT_LIST_HEAD(&alloc->pages[i].lru);
|
|
}
|
|
|
|
buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
|
|
if (!buffer) {
|
|
ret = -ENOMEM;
|
|
failure_string = "alloc buffer struct";
|
|
goto err_alloc_buf_struct_failed;
|
|
}
|
|
|
|
buffer->user_data = alloc->buffer;
|
|
list_add(&buffer->entry, &alloc->buffers);
|
|
buffer->free = 1;
|
|
binder_insert_free_buffer(alloc, buffer);
|
|
alloc->free_async_space = alloc->buffer_size / 2;
|
|
|
|
/* Signal binder_alloc is fully initialized */
|
|
binder_alloc_set_vma(alloc, vma);
|
|
|
|
return 0;
|
|
|
|
err_alloc_buf_struct_failed:
|
|
kfree(alloc->pages);
|
|
alloc->pages = NULL;
|
|
err_alloc_pages_failed:
|
|
alloc->buffer = 0;
|
|
mutex_lock(&binder_alloc_mmap_lock);
|
|
alloc->buffer_size = 0;
|
|
err_already_mapped:
|
|
mutex_unlock(&binder_alloc_mmap_lock);
|
|
err_invalid_mm:
|
|
binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
|
|
"%s: %d %lx-%lx %s failed %d\n", __func__,
|
|
alloc->pid, vma->vm_start, vma->vm_end,
|
|
failure_string, ret);
|
|
return ret;
|
|
}
|
|
|
|
|
|
void binder_alloc_deferred_release(struct binder_alloc *alloc)
|
|
{
|
|
struct rb_node *n;
|
|
int buffers, page_count;
|
|
struct binder_buffer *buffer;
|
|
|
|
buffers = 0;
|
|
spin_lock(&alloc->lock);
|
|
BUG_ON(alloc->vma);
|
|
|
|
while ((n = rb_first(&alloc->allocated_buffers))) {
|
|
buffer = rb_entry(n, struct binder_buffer, rb_node);
|
|
|
|
/* Transaction should already have been freed */
|
|
BUG_ON(buffer->transaction);
|
|
|
|
if (buffer->clear_on_free) {
|
|
binder_alloc_clear_buf(alloc, buffer);
|
|
buffer->clear_on_free = false;
|
|
}
|
|
binder_free_buf_locked(alloc, buffer);
|
|
buffers++;
|
|
}
|
|
|
|
while (!list_empty(&alloc->buffers)) {
|
|
buffer = list_first_entry(&alloc->buffers,
|
|
struct binder_buffer, entry);
|
|
WARN_ON(!buffer->free);
|
|
|
|
list_del(&buffer->entry);
|
|
WARN_ON_ONCE(!list_empty(&alloc->buffers));
|
|
kfree(buffer);
|
|
}
|
|
|
|
page_count = 0;
|
|
if (alloc->pages) {
|
|
int i;
|
|
|
|
for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
|
|
unsigned long page_addr;
|
|
bool on_lru;
|
|
|
|
if (!alloc->pages[i].page_ptr)
|
|
continue;
|
|
|
|
on_lru = list_lru_del_obj(&binder_freelist,
|
|
&alloc->pages[i].lru);
|
|
page_addr = alloc->buffer + i * PAGE_SIZE;
|
|
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
|
|
"%s: %d: page %d %s\n",
|
|
__func__, alloc->pid, i,
|
|
on_lru ? "on lru" : "active");
|
|
__free_page(alloc->pages[i].page_ptr);
|
|
page_count++;
|
|
}
|
|
kfree(alloc->pages);
|
|
}
|
|
spin_unlock(&alloc->lock);
|
|
if (alloc->mm)
|
|
mmdrop(alloc->mm);
|
|
|
|
binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE,
|
|
"%s: %d buffers %d, pages %d\n",
|
|
__func__, alloc->pid, buffers, page_count);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_print_allocated() - print buffer info
|
|
* @m: seq_file for output via seq_printf()
|
|
* @alloc: binder_alloc for this proc
|
|
*
|
|
* Prints information about every buffer associated with
|
|
* the binder_alloc state to the given seq_file
|
|
*/
|
|
void binder_alloc_print_allocated(struct seq_file *m,
|
|
struct binder_alloc *alloc)
|
|
{
|
|
struct binder_buffer *buffer;
|
|
struct rb_node *n;
|
|
|
|
spin_lock(&alloc->lock);
|
|
for (n = rb_first(&alloc->allocated_buffers); n; n = rb_next(n)) {
|
|
buffer = rb_entry(n, struct binder_buffer, rb_node);
|
|
seq_printf(m, " buffer %d: %lx size %zd:%zd:%zd %s\n",
|
|
buffer->debug_id,
|
|
buffer->user_data - alloc->buffer,
|
|
buffer->data_size, buffer->offsets_size,
|
|
buffer->extra_buffers_size,
|
|
buffer->transaction ? "active" : "delivered");
|
|
}
|
|
spin_unlock(&alloc->lock);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_print_pages() - print page usage
|
|
* @m: seq_file for output via seq_printf()
|
|
* @alloc: binder_alloc for this proc
|
|
*/
|
|
void binder_alloc_print_pages(struct seq_file *m,
|
|
struct binder_alloc *alloc)
|
|
{
|
|
struct binder_lru_page *page;
|
|
int i;
|
|
int active = 0;
|
|
int lru = 0;
|
|
int free = 0;
|
|
|
|
spin_lock(&alloc->lock);
|
|
/*
|
|
* Make sure the binder_alloc is fully initialized, otherwise we might
|
|
* read inconsistent state.
|
|
*/
|
|
if (binder_alloc_get_vma(alloc) != NULL) {
|
|
for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
|
|
page = &alloc->pages[i];
|
|
if (!page->page_ptr)
|
|
free++;
|
|
else if (list_empty(&page->lru))
|
|
active++;
|
|
else
|
|
lru++;
|
|
}
|
|
}
|
|
spin_unlock(&alloc->lock);
|
|
seq_printf(m, " pages: %d:%d:%d\n", active, lru, free);
|
|
seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_get_allocated_count() - return count of buffers
|
|
* @alloc: binder_alloc for this proc
|
|
*
|
|
* Return: count of allocated buffers
|
|
*/
|
|
int binder_alloc_get_allocated_count(struct binder_alloc *alloc)
|
|
{
|
|
struct rb_node *n;
|
|
int count = 0;
|
|
|
|
spin_lock(&alloc->lock);
|
|
for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n))
|
|
count++;
|
|
spin_unlock(&alloc->lock);
|
|
return count;
|
|
}
|
|
|
|
|
|
/**
|
|
* binder_alloc_vma_close() - invalidate address space
|
|
* @alloc: binder_alloc for this proc
|
|
*
|
|
* Called from binder_vma_close() when releasing address space.
|
|
* Clears alloc->vma to prevent new incoming transactions from
|
|
* allocating more buffers.
|
|
*/
|
|
void binder_alloc_vma_close(struct binder_alloc *alloc)
|
|
{
|
|
binder_alloc_set_vma(alloc, NULL);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_free_page() - shrinker callback to free pages
|
|
* @item: item to free
|
|
* @lock: lock protecting the item
|
|
* @cb_arg: callback argument
|
|
*
|
|
* Called from list_lru_walk() in binder_shrink_scan() to free
|
|
* up pages when the system is under memory pressure.
|
|
*/
|
|
enum lru_status binder_alloc_free_page(struct list_head *item,
|
|
struct list_lru_one *lru,
|
|
spinlock_t *lock,
|
|
void *cb_arg)
|
|
__must_hold(lock)
|
|
{
|
|
struct binder_lru_page *page = container_of(item, typeof(*page), lru);
|
|
struct binder_alloc *alloc = page->alloc;
|
|
struct mm_struct *mm = alloc->mm;
|
|
struct vm_area_struct *vma;
|
|
struct page *page_to_free;
|
|
unsigned long page_addr;
|
|
size_t index;
|
|
|
|
if (!mmget_not_zero(mm))
|
|
goto err_mmget;
|
|
if (!mmap_read_trylock(mm))
|
|
goto err_mmap_read_lock_failed;
|
|
if (!spin_trylock(&alloc->lock))
|
|
goto err_get_alloc_lock_failed;
|
|
if (!page->page_ptr)
|
|
goto err_page_already_freed;
|
|
|
|
index = page - alloc->pages;
|
|
page_addr = alloc->buffer + index * PAGE_SIZE;
|
|
|
|
vma = vma_lookup(mm, page_addr);
|
|
if (vma && vma != binder_alloc_get_vma(alloc))
|
|
goto err_invalid_vma;
|
|
|
|
trace_binder_unmap_kernel_start(alloc, index);
|
|
|
|
page_to_free = page->page_ptr;
|
|
page->page_ptr = NULL;
|
|
|
|
trace_binder_unmap_kernel_end(alloc, index);
|
|
|
|
list_lru_isolate(lru, item);
|
|
spin_unlock(&alloc->lock);
|
|
spin_unlock(lock);
|
|
|
|
if (vma) {
|
|
trace_binder_unmap_user_start(alloc, index);
|
|
|
|
zap_page_range_single(vma, page_addr, PAGE_SIZE, NULL);
|
|
|
|
trace_binder_unmap_user_end(alloc, index);
|
|
}
|
|
|
|
mmap_read_unlock(mm);
|
|
mmput_async(mm);
|
|
__free_page(page_to_free);
|
|
|
|
spin_lock(lock);
|
|
return LRU_REMOVED_RETRY;
|
|
|
|
err_invalid_vma:
|
|
err_page_already_freed:
|
|
spin_unlock(&alloc->lock);
|
|
err_get_alloc_lock_failed:
|
|
mmap_read_unlock(mm);
|
|
err_mmap_read_lock_failed:
|
|
mmput_async(mm);
|
|
err_mmget:
|
|
return LRU_SKIP;
|
|
}
|
|
|
|
static unsigned long
|
|
binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
|
|
{
|
|
return list_lru_count(&binder_freelist);
|
|
}
|
|
|
|
static unsigned long
|
|
binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
|
|
{
|
|
return list_lru_walk(&binder_freelist, binder_alloc_free_page,
|
|
NULL, sc->nr_to_scan);
|
|
}
|
|
|
|
static struct shrinker *binder_shrinker;
|
|
|
|
/**
|
|
* binder_alloc_init() - called by binder_open() for per-proc initialization
|
|
* @alloc: binder_alloc for this proc
|
|
*
|
|
* Called from binder_open() to initialize binder_alloc fields for
|
|
* new binder proc
|
|
*/
|
|
void binder_alloc_init(struct binder_alloc *alloc)
|
|
{
|
|
alloc->pid = current->group_leader->pid;
|
|
alloc->mm = current->mm;
|
|
mmgrab(alloc->mm);
|
|
spin_lock_init(&alloc->lock);
|
|
INIT_LIST_HEAD(&alloc->buffers);
|
|
}
|
|
|
|
int binder_alloc_shrinker_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = list_lru_init(&binder_freelist);
|
|
if (ret)
|
|
return ret;
|
|
|
|
binder_shrinker = shrinker_alloc(0, "android-binder");
|
|
if (!binder_shrinker) {
|
|
list_lru_destroy(&binder_freelist);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
binder_shrinker->count_objects = binder_shrink_count;
|
|
binder_shrinker->scan_objects = binder_shrink_scan;
|
|
|
|
shrinker_register(binder_shrinker);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void binder_alloc_shrinker_exit(void)
|
|
{
|
|
shrinker_free(binder_shrinker);
|
|
list_lru_destroy(&binder_freelist);
|
|
}
|
|
|
|
/**
|
|
* check_buffer() - verify that buffer/offset is safe to access
|
|
* @alloc: binder_alloc for this proc
|
|
* @buffer: binder buffer to be accessed
|
|
* @offset: offset into @buffer data
|
|
* @bytes: bytes to access from offset
|
|
*
|
|
* Check that the @offset/@bytes are within the size of the given
|
|
* @buffer and that the buffer is currently active and not freeable.
|
|
* Offsets must also be multiples of sizeof(u32). The kernel is
|
|
* allowed to touch the buffer in two cases:
|
|
*
|
|
* 1) when the buffer is being created:
|
|
* (buffer->free == 0 && buffer->allow_user_free == 0)
|
|
* 2) when the buffer is being torn down:
|
|
* (buffer->free == 0 && buffer->transaction == NULL).
|
|
*
|
|
* Return: true if the buffer is safe to access
|
|
*/
|
|
static inline bool check_buffer(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t offset, size_t bytes)
|
|
{
|
|
size_t buffer_size = binder_alloc_buffer_size(alloc, buffer);
|
|
|
|
return buffer_size >= bytes &&
|
|
offset <= buffer_size - bytes &&
|
|
IS_ALIGNED(offset, sizeof(u32)) &&
|
|
!buffer->free &&
|
|
(!buffer->allow_user_free || !buffer->transaction);
|
|
}
|
|
|
|
/**
|
|
* binder_alloc_copy_user_to_buffer() - copy src user to tgt user
|
|
* @alloc: binder_alloc for this proc
|
|
* @buffer: binder buffer to be accessed
|
|
* @buffer_offset: offset into @buffer data
|
|
* @from: userspace pointer to source buffer
|
|
* @bytes: bytes to copy
|
|
*
|
|
* Copy bytes from source userspace to target buffer.
|
|
*
|
|
* Return: bytes remaining to be copied
|
|
*/
|
|
unsigned long
|
|
binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t buffer_offset,
|
|
const void __user *from,
|
|
size_t bytes)
|
|
{
|
|
if (!check_buffer(alloc, buffer, buffer_offset, bytes))
|
|
return bytes;
|
|
|
|
while (bytes) {
|
|
unsigned long size;
|
|
unsigned long ret;
|
|
struct page *page;
|
|
pgoff_t pgoff;
|
|
void *kptr;
|
|
|
|
page = binder_alloc_get_page(alloc, buffer,
|
|
buffer_offset, &pgoff);
|
|
size = min_t(size_t, bytes, PAGE_SIZE - pgoff);
|
|
kptr = kmap_local_page(page) + pgoff;
|
|
ret = copy_from_user(kptr, from, size);
|
|
kunmap_local(kptr);
|
|
if (ret)
|
|
return bytes - size + ret;
|
|
bytes -= size;
|
|
from += size;
|
|
buffer_offset += size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int binder_alloc_do_buffer_copy(struct binder_alloc *alloc,
|
|
bool to_buffer,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t buffer_offset,
|
|
void *ptr,
|
|
size_t bytes)
|
|
{
|
|
/* All copies must be 32-bit aligned and 32-bit size */
|
|
if (!check_buffer(alloc, buffer, buffer_offset, bytes))
|
|
return -EINVAL;
|
|
|
|
while (bytes) {
|
|
unsigned long size;
|
|
struct page *page;
|
|
pgoff_t pgoff;
|
|
|
|
page = binder_alloc_get_page(alloc, buffer,
|
|
buffer_offset, &pgoff);
|
|
size = min_t(size_t, bytes, PAGE_SIZE - pgoff);
|
|
if (to_buffer)
|
|
memcpy_to_page(page, pgoff, ptr, size);
|
|
else
|
|
memcpy_from_page(ptr, page, pgoff, size);
|
|
bytes -= size;
|
|
pgoff = 0;
|
|
ptr = ptr + size;
|
|
buffer_offset += size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int binder_alloc_copy_to_buffer(struct binder_alloc *alloc,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t buffer_offset,
|
|
void *src,
|
|
size_t bytes)
|
|
{
|
|
return binder_alloc_do_buffer_copy(alloc, true, buffer, buffer_offset,
|
|
src, bytes);
|
|
}
|
|
|
|
int binder_alloc_copy_from_buffer(struct binder_alloc *alloc,
|
|
void *dest,
|
|
struct binder_buffer *buffer,
|
|
binder_size_t buffer_offset,
|
|
size_t bytes)
|
|
{
|
|
return binder_alloc_do_buffer_copy(alloc, false, buffer, buffer_offset,
|
|
dest, bytes);
|
|
}
|