[PATCH v2 1/3] lmb: Return -EFAULT when requested region is not part of memory map

[Jonas Karlman <jonas@kwiboo.se>]

lmb_alloc_addr() is documented to return -EINVAL when the requested
memory region is not part of the LMB memory map. However, -EINVAL is
also used to e.g. indicate that a NULL pointer is passed as the addr
parameter or when the requested memory region partially overlaps an
existing region.

Change lmb_alloc_addr() to return -EFAULT when the requested memory
region is not part of the LMB memory map to make the type of error known
to callers. Also extend unit tests to validate that the return code has
stay the same when the requested memory region partially overlaps.

No caller of lmb_alloc_addr() is checking what type of error code is
returned, so this change has no intended behavior change.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
 include/lmb.h  |  2 +-
 lib/lmb.c      |  4 +++-
 test/lib/lmb.c | 10 +++++++++-
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/lmb.h b/include/lmb.h
index ed472e9ef2e1..028dabb19e86 100644
--- a/include/lmb.h
+++ b/include/lmb.h
@@ -124,7 +124,7 @@ struct lmb {
  * Return: 0 on success, -ve value on failure
  *
  * When the allocation is of type @LMB_MEM_ALLOC_ADDR, the return value can
- * be -EINVAL if the requested memory region is not part of the LMB memory
+ * be -EFAULT if the requested memory region is not part of the LMB memory
  * map, and -EEXIST if the requested region is already allocated.
  */
 int lmb_alloc_mem(enum lmb_mem_type type, u64 align, phys_addr_t *addr,
diff --git a/lib/lmb.c b/lib/lmb.c
index 77440a48486c..f7c2e826d067 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -752,9 +752,11 @@ static int _lmb_alloc_addr(phys_addr_t base, phys_size_t size, u32 flags)
 				      base + size - 1, 1))
 			/* ok, reserve the memory */
 			return lmb_reserve(base, size, flags);
+
+		return -EINVAL;
 	}
 
-	return -EINVAL;
+	return -EFAULT;
 }
 
 int lmb_alloc_mem(enum lmb_mem_type type, u64 align, phys_addr_t *addr,
diff --git a/test/lib/lmb.c b/test/lib/lmb.c
index b6259bef4426..b93b903f99f9 100644
--- a/test/lib/lmb.c
+++ b/test/lib/lmb.c
@@ -779,11 +779,19 @@ static int test_alloc_addr(struct unit_test_state *uts, const phys_addr_t ram)
 	/* check that allocating outside memory fails */
 	if (ram_end != 0) {
 		ret = lmb_alloc_addr(ram_end, 1, LMB_NONE);
+		ut_asserteq(ret, -EFAULT);
+		ret = lmb_alloc_addr(ram_end - 1, 2, LMB_NOMAP);
+		ut_asserteq(ret, -EINVAL);
+		ret = lmb_alloc_addr(ram_end - 1, 2, LMB_NOOVERWRITE);
 		ut_asserteq(ret, -EINVAL);
 	}
 	if (ram != 0) {
 		ret = lmb_alloc_addr(ram - 1, 1, LMB_NONE);
-		ut_asserteq(ret, -EINVAL);
+		ut_asserteq(ret, -EFAULT);
+		ret = lmb_alloc_addr(ram - 1, 2, LMB_NOMAP);
+		ut_asserteq(ret, -EEXIST);
+		ret = lmb_alloc_addr(ram - 1, 2, LMB_NOOVERWRITE);
+		ut_asserteq(ret, -EEXIST);
 	}
 
 	lmb_pop(&store);
-- 
2.55.0