of: Eliminate of_allnodes list
The device tree structure is composed of two lists; the 'allnodes' list
which is a singly linked list containing every node in the tree, and the
child->parent structure where each parent node has a singly linked list
of children. All of the data in the allnodes list can be easily
reproduced with the parent-child lists, so of_allnodes is actually
unnecessary. Remove it entirely which saves a bit of memory and
simplifies the data structure quite a lot.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Gaurav Minocha <gaurav.minocha.os@gmail.com>
Cc: Pantelis Antoniou <pantelis@pantelis.antoniou@konsulko.com>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index d1ffca8..1d30b9f 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -145,15 +145,15 @@
* @mem: Memory chunk to use for allocating device nodes and properties
* @p: pointer to node in flat tree
* @dad: Parent struct device_node
- * @allnextpp: pointer to ->allnext from last allocated device_node
* @fpsize: Size of the node path up at the current depth.
*/
static void * unflatten_dt_node(void *blob,
void *mem,
int *poffset,
struct device_node *dad,
- struct device_node ***allnextpp,
- unsigned long fpsize)
+ struct device_node **nodepp,
+ unsigned long fpsize,
+ bool dryrun)
{
const __be32 *p;
struct device_node *np;
@@ -200,7 +200,7 @@
np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
__alignof__(struct device_node));
- if (allnextpp) {
+ if (!dryrun) {
char *fn;
of_node_init(np);
np->full_name = fn = ((char *)np) + sizeof(*np);
@@ -222,8 +222,6 @@
memcpy(fn, pathp, l);
prev_pp = &np->properties;
- **allnextpp = np;
- *allnextpp = &np->allnext;
if (dad != NULL) {
np->parent = dad;
/* we temporarily use the next field as `last_child'*/
@@ -254,7 +252,7 @@
has_name = 1;
pp = unflatten_dt_alloc(&mem, sizeof(struct property),
__alignof__(struct property));
- if (allnextpp) {
+ if (!dryrun) {
/* We accept flattened tree phandles either in
* ePAPR-style "phandle" properties, or the
* legacy "linux,phandle" properties. If both
@@ -296,7 +294,7 @@
sz = (pa - ps) + 1;
pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
__alignof__(struct property));
- if (allnextpp) {
+ if (!dryrun) {
pp->name = "name";
pp->length = sz;
pp->value = pp + 1;
@@ -308,7 +306,7 @@
(char *)pp->value);
}
}
- if (allnextpp) {
+ if (!dryrun) {
*prev_pp = NULL;
np->name = of_get_property(np, "name", NULL);
np->type = of_get_property(np, "device_type", NULL);
@@ -324,11 +322,13 @@
if (depth < 0)
depth = 0;
while (*poffset > 0 && depth > old_depth)
- mem = unflatten_dt_node(blob, mem, poffset, np, allnextpp,
- fpsize);
+ mem = unflatten_dt_node(blob, mem, poffset, np, NULL,
+ fpsize, dryrun);
if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND)
pr_err("unflatten: error %d processing FDT\n", *poffset);
+ if (nodepp)
+ *nodepp = np;
return mem;
}
@@ -352,7 +352,6 @@
unsigned long size;
int start;
void *mem;
- struct device_node **allnextp = mynodes;
pr_debug(" -> unflatten_device_tree()\n");
@@ -373,7 +372,7 @@
/* First pass, scan for size */
start = 0;
- size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0);
+ size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0, true);
size = ALIGN(size, 4);
pr_debug(" size is %lx, allocating...\n", size);
@@ -388,11 +387,10 @@
/* Second pass, do actual unflattening */
start = 0;
- unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
+ unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false);
if (be32_to_cpup(mem + size) != 0xdeadbeef)
pr_warning("End of tree marker overwritten: %08x\n",
be32_to_cpup(mem + size));
- *allnextp = NULL;
pr_debug(" <- unflatten_device_tree()\n");
}
@@ -1041,7 +1039,7 @@
*/
void __init unflatten_device_tree(void)
{
- __unflatten_device_tree(initial_boot_params, &of_allnodes,
+ __unflatten_device_tree(initial_boot_params, &of_root,
early_init_dt_alloc_memory_arch);
/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */