From: Laura Abbott <lauraa@codeaurora.org>
Date: Thu, 9 Oct 2014 22:26:38 +0000 (-0700)
Subject: lib/genalloc.c: add genpool range check function
X-Git-Tag: firefly_0821_release~3680^2~32^2^2~1
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=e4d45c70b7bad66ada07b19edcc1ffa692c1845b;p=firefly-linux-kernel-4.4.55.git

lib/genalloc.c: add genpool range check function

After allocating an address from a particular genpool, there is no good
way to verify if that address actually belongs to a genpool.  Introduce
addr_in_gen_pool which will return if an address plus size falls
completely within the genpool range.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Riley <davidriley@chromium.org>
Cc: Ritesh Harjain <ritesh.harjani@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 9efb3a421d55d30b65fb0dbee05108d15c6c55f7)
Signed-off-by: Mark Brown <broonie@kernel.org>
---

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index d278793da6e7..bc24f34c6ecb 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -117,6 +117,9 @@ extern struct gen_pool *devm_gen_pool_create(struct device *dev,
 		int min_alloc_order, int nid);
 extern struct gen_pool *dev_get_gen_pool(struct device *dev);
 
+bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start,
+			size_t size);
+
 #ifdef CONFIG_OF
 extern struct gen_pool *of_get_named_gen_pool(struct device_node *np,
 	const char *propname, int index);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 095b8f9b1a50..f8b131bd920e 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -368,6 +368,35 @@ void gen_pool_for_each_chunk(struct gen_pool *pool,
 }
 EXPORT_SYMBOL(gen_pool_for_each_chunk);
 
+/**
+ * addr_in_gen_pool - checks if an address falls within the range of a pool
+ * @pool:	the generic memory pool
+ * @start:	start address
+ * @size:	size of the region
+ *
+ * Check if the range of addresses falls within the specified pool. Returns
+ * true if the entire range is contained in the pool and false otherwise.
+ */
+bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start,
+			size_t size)
+{
+	bool found = false;
+	unsigned long end = start + size;
+	struct gen_pool_chunk *chunk;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) {
+		if (start >= chunk->start_addr && start <= chunk->end_addr) {
+			if (end <= chunk->end_addr) {
+				found = true;
+				break;
+			}
+		}
+	}
+	rcu_read_unlock();
+	return found;
+}
+
 /**
  * gen_pool_avail - get available free space of the pool
  * @pool: pool to get available free space