binder: rename alloc->buffer to vm_start

The alloc->buffer field in struct binder_alloc stores the starting
address of the mapped vma, rename this field to alloc->vm_start to
better reflect its purpose. It also avoids confusion with the binder
buffer concept, e.g. transaction->buffer.

No functional changes in this patch.

Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20241210143114.661252-7-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

5 files changed, 19 insertions, 19 deletions

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index ef353ca13c35..9962c606cabd 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -6374,7 +6374,7 @@ static void print_binder_transaction_ilocked(struct seq_file *m,
 		seq_printf(m, " node %d", buffer->target_node->debug_id);
 	seq_printf(m, " size %zd:%zd offset %lx\n",
 		   buffer->data_size, buffer->offsets_size,
-		   proc->alloc.buffer - buffer->user_data);
+		   proc->alloc.vm_start - buffer->user_data);
 }
 
 static void print_binder_work_ilocked(struct seq_file *m,
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index ed79d7c146c8..9cb47e1bc6be 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -61,7 +61,7 @@ static size_t binder_alloc_buffer_size(struct binder_alloc *alloc,
 				       struct binder_buffer *buffer)
 {
 	if (list_is_last(&buffer->entry, &alloc->buffers))
-		return alloc->buffer + alloc->buffer_size - buffer->user_data;
+		return alloc->vm_start + alloc->buffer_size - buffer->user_data;
 	return binder_buffer_next(buffer)->user_data - buffer->user_data;
 }
 
@@ -203,7 +203,7 @@ static void binder_lru_freelist_add(struct binder_alloc *alloc,
 		size_t index;
 		int ret;
 
-		index = (page_addr - alloc->buffer) / PAGE_SIZE;
+		index = (page_addr - alloc->vm_start) / PAGE_SIZE;
 		page = binder_get_installed_page(alloc, index);
 		if (!page)
 			continue;
@@ -305,7 +305,7 @@ static int binder_install_single_page(struct binder_alloc *alloc,
 					       FOLL_NOFAULT, &page, NULL);
 		if (npages <= 0) {
 			pr_err("%d: failed to find page at offset %lx\n",
-			       alloc->pid, addr - alloc->buffer);
+			       alloc->pid, addr - alloc->vm_start);
 			ret = -ESRCH;
 			break;
 		}
@@ -317,7 +317,7 @@ static int binder_install_single_page(struct binder_alloc *alloc,
 	default:
 		binder_free_page(page);
 		pr_err("%d: %s failed to insert page at offset %lx with %d\n",
-		       alloc->pid, __func__, addr - alloc->buffer, ret);
+		       alloc->pid, __func__, addr - alloc->vm_start, ret);
 		ret = -ENOMEM;
 		break;
 	}
@@ -342,7 +342,7 @@ static int binder_install_buffer_pages(struct binder_alloc *alloc,
 		unsigned long index;
 		int ret;
 
-		index = (page_addr - alloc->buffer) / PAGE_SIZE;
+		index = (page_addr - alloc->vm_start) / PAGE_SIZE;
 		if (binder_get_installed_page(alloc, index))
 			continue;
 
@@ -371,7 +371,7 @@ static void binder_lru_freelist_del(struct binder_alloc *alloc,
 		unsigned long index;
 		bool on_lru;
 
-		index = (page_addr - alloc->buffer) / PAGE_SIZE;
+		index = (page_addr - alloc->vm_start) / PAGE_SIZE;
 		page = binder_get_installed_page(alloc, index);
 
 		if (page) {
@@ -723,8 +723,8 @@ static void binder_free_buf_locked(struct binder_alloc *alloc,
 	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);
+	BUG_ON(buffer->user_data < alloc->vm_start);
+	BUG_ON(buffer->user_data > alloc->vm_start + alloc->buffer_size);
 
 	if (buffer->async_transaction) {
 		alloc->free_async_space += buffer_size;
@@ -783,7 +783,7 @@ static struct page *binder_alloc_get_page(struct binder_alloc *alloc,
 					  pgoff_t *pgoffp)
 {
 	binder_size_t buffer_space_offset = buffer_offset +
-		(buffer->user_data - alloc->buffer);
+		(buffer->user_data - alloc->vm_start);
 	pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK;
 	size_t index = buffer_space_offset >> PAGE_SHIFT;
 
@@ -882,7 +882,7 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
 				   SZ_4M);
 	mutex_unlock(&binder_alloc_mmap_lock);
 
-	alloc->buffer = vma->vm_start;
+	alloc->vm_start = vma->vm_start;
 
 	alloc->pages = kvcalloc(alloc->buffer_size / PAGE_SIZE,
 				sizeof(alloc->pages[0]),
@@ -900,7 +900,7 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
 		goto err_alloc_buf_struct_failed;
 	}
 
-	buffer->user_data = alloc->buffer;
+	buffer->user_data = alloc->vm_start;
 	list_add(&buffer->entry, &alloc->buffers);
 	buffer->free = 1;
 	binder_insert_free_buffer(alloc, buffer);
@@ -915,7 +915,7 @@ err_alloc_buf_struct_failed:
 	kvfree(alloc->pages);
 	alloc->pages = NULL;
 err_alloc_pages_failed:
-	alloc->buffer = 0;
+	alloc->vm_start = 0;
 	mutex_lock(&binder_alloc_mmap_lock);
 	alloc->buffer_size = 0;
 err_already_mapped:
@@ -1016,7 +1016,7 @@ void binder_alloc_print_allocated(struct seq_file *m,
 		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->user_data - alloc->vm_start,
 			   buffer->data_size, buffer->offsets_size,
 			   buffer->extra_buffers_size,
 			   buffer->transaction ? "active" : "delivered");
@@ -1121,7 +1121,7 @@ enum lru_status binder_alloc_free_page(struct list_head *item,
 		goto err_get_alloc_mutex_failed;
 
 	index = mdata->page_index;
-	page_addr = alloc->buffer + index * PAGE_SIZE;
+	page_addr = alloc->vm_start + index * PAGE_SIZE;
 
 	vma = vma_lookup(mm, page_addr);
 	/*
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index 3ebb12afd4de..feecd7414241 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -83,7 +83,7 @@ static inline struct list_head *page_to_lru(struct page *p)
  * struct binder_alloc - per-binder proc state for binder allocator
  * @mutex:              protects binder_alloc fields
  * @mm:                 copy of task->mm (invariant after open)
- * @buffer:             base of per-proc address space mapped via mmap
+ * @vm_start:           base of per-proc address space mapped via mmap
  * @buffers:            list of all buffers for this proc
  * @free_buffers:       rb tree of buffers available for allocation
  *                      sorted by size
@@ -107,7 +107,7 @@ static inline struct list_head *page_to_lru(struct page *p)
 struct binder_alloc {
 	struct mutex mutex;
 	struct mm_struct *mm;
-	unsigned long buffer;
+	unsigned long vm_start;
 	struct list_head buffers;
 	struct rb_root free_buffers;
 	struct rb_root allocated_buffers;
diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c
index 6a64847a8555..c88735c54848 100644
--- a/drivers/android/binder_alloc_selftest.c
+++ b/drivers/android/binder_alloc_selftest.c
@@ -104,7 +104,7 @@ static bool check_buffer_pages_allocated(struct binder_alloc *alloc,
 	end = PAGE_ALIGN(buffer->user_data + size);
 	page_addr = buffer->user_data;
 	for (; page_addr < end; page_addr += PAGE_SIZE) {
-		page_index = (page_addr - alloc->buffer) / PAGE_SIZE;
+		page_index = (page_addr - alloc->vm_start) / PAGE_SIZE;
 		if (!alloc->pages[page_index] ||
 		    !list_empty(page_to_lru(alloc->pages[page_index]))) {
 			pr_err("expect alloc but is %s at page index %d\n",
diff --git a/drivers/android/binder_trace.h b/drivers/android/binder_trace.h
index fe38c6fc65d0..16de1b9e72f7 100644
--- a/drivers/android/binder_trace.h
+++ b/drivers/android/binder_trace.h
@@ -328,7 +328,7 @@ TRACE_EVENT(binder_update_page_range,
 	TP_fast_assign(
 		__entry->proc = alloc->pid;
 		__entry->allocate = allocate;
-		__entry->offset = start - alloc->buffer;
+		__entry->offset = start - alloc->vm_start;
 		__entry->size = end - start;
 	),
 	TP_printk("proc=%d allocate=%d offset=%zu size=%zu",