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-rw-r--r--drivers/base/memory.c42
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index c54e80fd25a8..0204384b4d1d 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -44,6 +44,11 @@ static inline unsigned long pfn_to_block_id(unsigned long pfn)
return base_memory_block_id(pfn_to_section_nr(pfn));
}
+static inline unsigned long phys_to_block_id(unsigned long phys)
+{
+ return pfn_to_block_id(PFN_DOWN(phys));
+}
+
static int memory_subsys_online(struct device *dev);
static int memory_subsys_offline(struct device *dev);
@@ -851,3 +856,40 @@ out:
printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
return ret;
}
+
+/**
+ * walk_memory_blocks - walk through all present memory blocks overlapped
+ * by the range [start, start + size)
+ *
+ * @start: start address of the memory range
+ * @size: size of the memory range
+ * @arg: argument passed to func
+ * @func: callback for each memory section walked
+ *
+ * This function walks through all present memory blocks overlapped by the
+ * range [start, start + size), calling func on each memory block.
+ *
+ * In case func() returns an error, walking is aborted and the error is
+ * returned.
+ */
+int walk_memory_blocks(unsigned long start, unsigned long size,
+ void *arg, walk_memory_blocks_func_t func)
+{
+ const unsigned long start_block_id = phys_to_block_id(start);
+ const unsigned long end_block_id = phys_to_block_id(start + size - 1);
+ struct memory_block *mem;
+ unsigned long block_id;
+ int ret = 0;
+
+ for (block_id = start_block_id; block_id <= end_block_id; block_id++) {
+ mem = find_memory_block_by_id(block_id, NULL);
+ if (!mem)
+ continue;
+
+ ret = func(mem, arg);
+ put_device(&mem->dev);
+ if (ret)
+ break;
+ }
+ return ret;
+}