[PATCH v2 1/2] of: overlay: rename variables to be consistent

From: frowand . list
Date: Sun Apr 10 2022 - 17:16:25 EST


From: Frank Rowand <frank.rowand@xxxxxxxx>

Variables change name across function calls when there is not a good
reason to do so. Fix by changing "fdt" to "new_fdt" and "tree" to
"overlay_tree".

The name disparity was confusing when creating the following commit.
The name changes are in this separate commit to make review of the
following commmit less complex.

Signed-off-by: Frank Rowand <frank.rowand@xxxxxxxx>
---
Changes since v1:
- This patch is added to the series.

drivers/of/overlay.c | 94 ++++++++++++++++++++++----------------------
1 file changed, 47 insertions(+), 47 deletions(-)

diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index d80160cf34bb..f74aa9ff67aa 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -57,7 +57,7 @@ struct fragment {
* struct overlay_changeset
* @id: changeset identifier
* @ovcs_list: list on which we are located
- * @fdt: base of memory allocated to hold aligned FDT that was unflattened to create @overlay_tree
+ * @new_fdt: Memory allocated to hold unflattened aligned FDT
* @overlay_tree: expanded device tree that contains the fragment nodes
* @count: count of fragment structures
* @fragments: fragment nodes in the overlay expanded device tree
@@ -67,7 +67,7 @@ struct fragment {
struct overlay_changeset {
int id;
struct list_head ovcs_list;
- const void *fdt;
+ const void *new_fdt;
struct device_node *overlay_tree;
int count;
struct fragment *fragments;
@@ -718,19 +718,20 @@ static struct device_node *find_target(struct device_node *info_node)

/**
* init_overlay_changeset() - initialize overlay changeset from overlay tree
- * @ovcs: Overlay changeset to build
- * @fdt: base of memory allocated to hold aligned FDT that was unflattened to create @tree
- * @tree: Contains the overlay fragments and overlay fixup nodes
+ * @ovcs: Overlay changeset to build
+ * @new_fdt: Memory allocated to hold unflattened aligned FDT
+ * @overlay_tree: Contains the overlay fragments and overlay fixup nodes
*
* Initialize @ovcs. Populate @ovcs->fragments with node information from
- * the top level of @tree. The relevant top level nodes are the fragment
- * nodes and the __symbols__ node. Any other top level node will be ignored.
+ * the top level of @overlay_tree. The relevant top level nodes are the
+ * fragment nodes and the __symbols__ node. Any other top level node will
+ * be ignored.
*
* Return: 0 on success, -ENOMEM if memory allocation failure, -EINVAL if error
- * detected in @tree, or -ENOSPC if idr_alloc() error.
+ * detected in @overlay_tree, or -ENOSPC if idr_alloc() error.
*/
static int init_overlay_changeset(struct overlay_changeset *ovcs,
- const void *fdt, struct device_node *tree)
+ const void *new_fdt, struct device_node *overlay_tree)
{
struct device_node *node, *overlay_node;
struct fragment *fragment;
@@ -741,17 +742,17 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
* Warn for some issues. Can not return -EINVAL for these until
* of_unittest_apply_overlay() is fixed to pass these checks.
*/
- if (!of_node_check_flag(tree, OF_DYNAMIC))
- pr_debug("%s() tree is not dynamic\n", __func__);
+ if (!of_node_check_flag(overlay_tree, OF_DYNAMIC))
+ pr_debug("%s() overlay_tree is not dynamic\n", __func__);

- if (!of_node_check_flag(tree, OF_DETACHED))
- pr_debug("%s() tree is not detached\n", __func__);
+ if (!of_node_check_flag(overlay_tree, OF_DETACHED))
+ pr_debug("%s() overlay_tree is not detached\n", __func__);

- if (!of_node_is_root(tree))
- pr_debug("%s() tree is not root\n", __func__);
+ if (!of_node_is_root(overlay_tree))
+ pr_debug("%s() overlay_tree is not root\n", __func__);

- ovcs->overlay_tree = tree;
- ovcs->fdt = fdt;
+ ovcs->overlay_tree = overlay_tree;
+ ovcs->new_fdt = new_fdt;

INIT_LIST_HEAD(&ovcs->ovcs_list);

@@ -764,7 +765,7 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
cnt = 0;

/* fragment nodes */
- for_each_child_of_node(tree, node) {
+ for_each_child_of_node(overlay_tree, node) {
overlay_node = of_get_child_by_name(node, "__overlay__");
if (overlay_node) {
cnt++;
@@ -772,7 +773,7 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
}
}

- node = of_get_child_by_name(tree, "__symbols__");
+ node = of_get_child_by_name(overlay_tree, "__symbols__");
if (node) {
cnt++;
of_node_put(node);
@@ -785,7 +786,7 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
}

cnt = 0;
- for_each_child_of_node(tree, node) {
+ for_each_child_of_node(overlay_tree, node) {
overlay_node = of_get_child_by_name(node, "__overlay__");
if (!overlay_node)
continue;
@@ -807,7 +808,7 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
* if there is a symbols fragment in ovcs->fragments[i] it is
* the final element in the array
*/
- node = of_get_child_by_name(tree, "__symbols__");
+ node = of_get_child_by_name(overlay_tree, "__symbols__");
if (node) {
ovcs->symbols_fragment = 1;
fragment = &fragments[cnt];
@@ -862,11 +863,11 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs)
kfree(ovcs->fragments);
/*
* There should be no live pointers into ovcs->overlay_tree and
- * ovcs->fdt due to the policy that overlay notifiers are not allowed
- * to retain pointers into the overlay devicetree.
+ * ovcs->new_fdt due to the policy that overlay notifiers are not
+ * allowed to retain pointers into the overlay devicetree.
*/
kfree(ovcs->overlay_tree);
- kfree(ovcs->fdt);
+ kfree(ovcs->new_fdt);
kfree(ovcs);
}

@@ -874,16 +875,15 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs)
* internal documentation
*
* of_overlay_apply() - Create and apply an overlay changeset
- * @fdt: base of memory allocated to hold the aligned FDT
- * @tree: Expanded overlay device tree
- * @ovcs_id: Pointer to overlay changeset id
+ * @new_fdt: Memory allocated to hold the aligned FDT
+ * @overlay_tree: Expanded overlay device tree
+ * @ovcs_id: Pointer to overlay changeset id
*
* Creates and applies an overlay changeset.
*
* If an error occurs in a pre-apply notifier, then no changes are made
* to the device tree.
*
-
* A non-zero return value will not have created the changeset if error is from:
* - parameter checks
* - building the changeset
@@ -913,29 +913,29 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs)
* id is returned to *ovcs_id.
*/

-static int of_overlay_apply(const void *fdt, struct device_node *tree,
- int *ovcs_id)
+static int of_overlay_apply(const void *new_fdt,
+ struct device_node *overlay_tree, int *ovcs_id)
{
struct overlay_changeset *ovcs;
int ret = 0, ret_revert, ret_tmp;

/*
- * As of this point, fdt and tree belong to the overlay changeset.
- * overlay changeset code is responsible for freeing them.
+ * As of this point, new_fdt and overlay_tree belong to the overlay
+ * changeset. overlay changeset code is responsible for freeing them.
*/

if (devicetree_corrupt()) {
pr_err("devicetree state suspect, refuse to apply overlay\n");
- kfree(fdt);
- kfree(tree);
+ kfree(new_fdt);
+ kfree(overlay_tree);
ret = -EBUSY;
goto out;
}

ovcs = kzalloc(sizeof(*ovcs), GFP_KERNEL);
if (!ovcs) {
- kfree(fdt);
- kfree(tree);
+ kfree(new_fdt);
+ kfree(overlay_tree);
ret = -ENOMEM;
goto out;
}
@@ -943,20 +943,20 @@ static int of_overlay_apply(const void *fdt, struct device_node *tree,
of_overlay_mutex_lock();
mutex_lock(&of_mutex);

- ret = of_resolve_phandles(tree);
+ ret = of_resolve_phandles(overlay_tree);
if (ret)
- goto err_free_tree;
+ goto err_free_overlay_tree;

- ret = init_overlay_changeset(ovcs, fdt, tree);
+ ret = init_overlay_changeset(ovcs, new_fdt, overlay_tree);
if (ret)
- goto err_free_tree;
+ goto err_free_overlay_tree;

/*
* after overlay_notify(), ovcs->overlay_tree related pointers may have
- * leaked to drivers, so can not kfree() tree, aka ovcs->overlay_tree;
- * and can not free memory containing aligned fdt. The aligned fdt
- * is contained within the memory at ovcs->fdt, possibly at an offset
- * from ovcs->fdt.
+ * leaked to drivers, so can not kfree() overlay_tree,
+ * aka ovcs->overlay_tree; and can not free memory containing aligned
+ * fdt. The aligned fdt is contained within the memory at
+ * ovcs->new_fdt, possibly at an offset from ovcs->new_fdt.
*/
ret = overlay_notify(ovcs, OF_OVERLAY_PRE_APPLY);
if (ret) {
@@ -997,9 +997,9 @@ static int of_overlay_apply(const void *fdt, struct device_node *tree,

goto out_unlock;

-err_free_tree:
- kfree(fdt);
- kfree(tree);
+err_free_overlay_tree:
+ kfree(new_fdt);
+ kfree(overlay_tree);

err_free_overlay_changeset:
free_overlay_changeset(ovcs);
--
Frank Rowand <frank.rowand@xxxxxxxx>