device_tree: Switch allocations to xzalloc()

The FIT code is already using xzalloc() everywhere, and that's the only
real consumer of device tree code right now. Chances are if you're
trying to unflatten an FDT and it doesn't fit into the heap you're
pretty much screwed anyway, so all the OOM handling feels a bit
unnecessary (and some functions will just silently fail because they
don't have a return value, which is bad). Let's just switch this all to
die on failed allocations.

Change-Id: I738f24d550a776653b2becd3d4f7d4d2cb3cc048
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32861
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 10 insertions, 45 deletions

diff --git a/src/lib/device_tree.c b/src/lib/device_tree.c
index 8dbc510c10..bb40eee231 100644
--- a/src/lib/device_tree.c
+++ b/src/lib/device_tree.c
@@ -16,6 +16,7 @@
  */
 
 #include <assert.h>
+#include <commonlib/stdlib.h>
 #include <console/console.h>
 #include <device_tree.h>
 #include <endian.h>
@@ -153,24 +154,6 @@ int fdt_skip_node(const void *blob, uint32_t start_offset)
 /*
  * Functions to turn a flattened tree into an unflattened one.
  */
-static struct device_tree_node *alloc_node(void)
-{
-	struct device_tree_node *buf = malloc(sizeof(struct device_tree_node));
-	if (!buf)
-		return NULL;
-	memset(buf, 0, sizeof(*buf));
-	return buf;
-}
-
-static struct device_tree_property *alloc_prop(void)
-{
-	struct device_tree_property *buf =
-		malloc(sizeof(struct device_tree_property));
-	if (!buf)
-		return NULL;
-	memset(buf, 0, sizeof(*buf));
-	return buf;
-}
 
 static int fdt_unflatten_node(const void *blob, uint32_t start_offset,
 			      struct device_tree_node **new_node)
@@ -185,18 +168,14 @@ static int fdt_unflatten_node(const void *blob, uint32_t start_offset,
 		return 0;
 	offset += size;
 
-	struct device_tree_node *node = alloc_node();
+	struct device_tree_node *node = xzalloc(sizeof(*node));
 	*new_node = node;
-	if (!node)
-		return 0;
 	node->name = name;
 
 	struct fdt_property fprop;
 	last = &node->properties;
 	while ((size = fdt_next_property(blob, offset, &fprop))) {
-		struct device_tree_property *prop = alloc_prop();
-		if (!prop)
-			return 0;
+		struct device_tree_property *prop = xzalloc(sizeof(*prop));
 		prop->prop = fprop;
 
 		list_insert_after(&prop->list_node, last);
@@ -227,10 +206,7 @@ static int fdt_unflatten_map_entry(const void *blob, uint32_t offset,
 	if (!size)
 		return 0;
 
-	struct device_tree_reserve_map_entry *entry = malloc(sizeof(*entry));
-	if (!entry)
-		return 0;
-	memset(entry, 0, sizeof(*entry));
+	struct device_tree_reserve_map_entry *entry = xzalloc(sizeof(*entry));
 	*new = entry;
 	entry->start = start;
 	entry->size = size;
@@ -240,11 +216,8 @@ static int fdt_unflatten_map_entry(const void *blob, uint32_t offset,
 
 struct device_tree *fdt_unflatten(const void *blob)
 {
-	struct device_tree *tree = malloc(sizeof(*tree));
+	struct device_tree *tree = xzalloc(sizeof(*tree));
 	const struct fdt_header *header = (const struct fdt_header *)blob;
-	if (!tree)
-		return NULL;
-	memset(tree, 0, sizeof(*tree));
 	tree->header = header;
 
 	uint32_t struct_offset = be32toh(header->structure_offset);
@@ -534,7 +507,7 @@ struct device_tree_node *dt_find_node(struct device_tree_node *parent,
 		if (!create)
 			return NULL;
 
-		found = alloc_node();
+		found = malloc(sizeof(*found));
 		if (!found)
 			return NULL;
 		found->name = strdup(*path);
@@ -804,9 +777,7 @@ void dt_add_bin_prop(struct device_tree_node *node, const char *name,
 		}
 	}
 
-	prop = alloc_prop();
-	if (!prop)
-		return;
+	prop = xzalloc(sizeof(*prop));
 	list_insert_after(&prop->list_node, &node->properties);
 	prop->prop.name = name;
 	prop->prop.data = data;
@@ -878,9 +849,7 @@ void dt_add_string_prop(struct device_tree_node *node, const char *name,
  */
 void dt_add_u32_prop(struct device_tree_node *node, const char *name, u32 val)
 {
-	u32 *val_ptr = malloc(sizeof(val));
-	if (!val_ptr)
-		return;
+	u32 *val_ptr = xmalloc(sizeof(val));
 	*val_ptr = htobe32(val);
 	dt_add_bin_prop(node, name, val_ptr, sizeof(*val_ptr));
 }
@@ -894,9 +863,7 @@ void dt_add_u32_prop(struct device_tree_node *node, const char *name, u32 val)
  */
 void dt_add_u64_prop(struct device_tree_node *node, const char *name, u64 val)
 {
-	u64 *val_ptr = malloc(sizeof(val));
-	if (!val_ptr)
-		return;
+	u64 *val_ptr = xmalloc(sizeof(val));
 	*val_ptr = htobe64(val);
 	dt_add_bin_prop(node, name, val_ptr, sizeof(*val_ptr));
 }
@@ -916,9 +883,7 @@ void dt_add_reg_prop(struct device_tree_node *node, u64 *addrs, u64 *sizes,
 {
 	int i;
 	size_t length = (addr_cells + size_cells) * sizeof(u32) * count;
-	u8 *data = malloc(length);
-	if (!data)
-		return;
+	u8 *data = xmalloc(length);
 	u8 *cur = data;
 
 	for (i = 0; i < count; i++) {