Revert "Revert "android: binder: stop saving a pointer to the VMA""

This reverts commit 72a94f8c14.

It breaks the Android KABI and will be brought back at a later time when
it is safe to do so.

Bug: 161946584
Change-Id: Iabf372c25f49e6deaf6c1d137b47c39608bb2187
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Greg Kroah-Hartman 2023-06-13 19:37:42 +00:00
parent 896fd52618
commit f9689ed69b
3 changed files with 11 additions and 12 deletions

View File

@ -214,7 +214,7 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
if (mm) {
mmap_read_lock(mm);
vma = alloc->vma;
vma = vma_lookup(mm, alloc->vma_addr);
}
if (!vma && need_mm) {
@ -315,11 +315,9 @@ static inline struct vm_area_struct *binder_alloc_get_vma(
{
struct vm_area_struct *vma = NULL;
if (alloc->vma) {
/* Look at description in binder_alloc_set_vma */
smp_rmb();
vma = alloc->vma;
}
if (alloc->vma_addr)
vma = vma_lookup(alloc->mm, alloc->vma_addr);
return vma;
}
@ -779,7 +777,7 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
buffer->free = 1;
binder_insert_free_buffer(alloc, buffer);
alloc->free_async_space = alloc->buffer_size / 2;
alloc->vma = vma;
alloc->vma_addr = vma->vm_start;
return 0;
@ -809,7 +807,8 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
buffers = 0;
mutex_lock(&alloc->mutex);
BUG_ON(alloc->vma);
BUG_ON(alloc->vma_addr &&
vma_lookup(alloc->mm, alloc->vma_addr));
while ((n = rb_first(&alloc->allocated_buffers))) {
buffer = rb_entry(n, struct binder_buffer, rb_node);
@ -961,7 +960,7 @@ int binder_alloc_get_allocated_count(struct binder_alloc *alloc)
*/
void binder_alloc_vma_close(struct binder_alloc *alloc)
{
alloc->vma = 0;
alloc->vma_addr = 0;
}
/**

View File

@ -75,7 +75,7 @@ struct binder_lru_page {
/**
* struct binder_alloc - per-binder proc state for binder allocator
* @mutex: protects binder_alloc fields
* @vma: vm_area_struct passed to mmap_handler
* @vma_addr: vm_area_struct->vm_start passed to mmap_handler
* (invariant after mmap)
* @mm: copy of task->mm (invariant after open)
* @buffer: base of per-proc address space mapped via mmap
@ -99,7 +99,7 @@ struct binder_lru_page {
*/
struct binder_alloc {
struct mutex mutex;
struct vm_area_struct *vma;
unsigned long vma_addr;
struct mm_struct *mm;
void __user *buffer;
struct list_head buffers;

View File

@ -287,7 +287,7 @@ void binder_selftest_alloc(struct binder_alloc *alloc)
if (!binder_selftest_run)
return;
mutex_lock(&binder_selftest_lock);
if (!binder_selftest_run || !alloc->vma)
if (!binder_selftest_run || !alloc->vma_addr)
goto done;
pr_info("STARTED\n");
binder_selftest_alloc_offset(alloc, end_offset, 0);