[PATCH] of: add pre-operation notifications
From: Alan Tull
Date: Wed Feb 24 2016 - 17:31:27 EST
Add pre-apply and pre-remove notifications.
For pre-apply notifications that result from creating an overlay,
include a device node to the overlay fragment in of_reconfig_data.
If a pre-apply notifier return error, reject the changeset.
Signed-off-by: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/of/base.c | 20 +++++++++++++
drivers/of/dynamic.c | 79 +++++++++++++++++++++++++++++++++++++++++++++-----
drivers/of/overlay.c | 46 +++++++++++++++++++++++++----
include/linux/of.h | 7 +++++
4 files changed, 138 insertions(+), 14 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 017dd94..6d170e0 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1719,6 +1719,12 @@ int of_add_property(struct device_node *np, struct property *prop)
mutex_lock(&of_mutex);
+ rc = of_property_notify(OF_RECONFIG_PRE_ADD_PROPERTY, np, prop, NULL);
+ if (rc) {
+ mutex_unlock(&of_mutex);
+ return rc;
+ }
+
raw_spin_lock_irqsave(&devtree_lock, flags);
rc = __of_add_property(np, prop);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
@@ -1778,6 +1784,13 @@ int of_remove_property(struct device_node *np, struct property *prop)
mutex_lock(&of_mutex);
+ rc = of_property_notify(OF_RECONFIG_PRE_REMOVE_PROPERTY, np, prop,
+ NULL);
+ if (rc) {
+ mutex_unlock(&of_mutex);
+ return rc;
+ }
+
raw_spin_lock_irqsave(&devtree_lock, flags);
rc = __of_remove_property(np, prop);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
@@ -1854,6 +1867,13 @@ int of_update_property(struct device_node *np, struct property *newprop)
mutex_lock(&of_mutex);
+ rc = of_property_notify(OF_RECONFIG_PRE_UPDATE_PROPERTY, np, newprop,
+ oldprop);
+ if (rc) {
+ mutex_unlock(&of_mutex);
+ return rc;
+ }
+
raw_spin_lock_irqsave(&devtree_lock, flags);
rc = __of_update_property(np, newprop, &oldprop);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index f0bf021..1ac9f49 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -85,6 +85,12 @@ const char *action_names[] = {
[OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY",
[OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY",
[OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY",
+
+ [OF_RECONFIG_PRE_ATTACH_NODE] = "PRE_ATTACH_NODE",
+ [OF_RECONFIG_PRE_DETACH_NODE] = "PRE_DETACH_NODE",
+ [OF_RECONFIG_PRE_ADD_PROPERTY] = "PRE_ADD_PROPERTY",
+ [OF_RECONFIG_PRE_REMOVE_PROPERTY] = "PRE_REMOVE_PROPERTY",
+ [OF_RECONFIG_PRE_UPDATE_PROPERTY] = "PRE_UPDATE_PROPERTY",
};
#endif
@@ -97,12 +103,17 @@ int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
switch (action) {
case OF_RECONFIG_ATTACH_NODE:
case OF_RECONFIG_DETACH_NODE:
+ case OF_RECONFIG_PRE_ATTACH_NODE:
+ case OF_RECONFIG_PRE_DETACH_NODE:
pr_debug("of/notify %-15s %s\n", action_names[action],
pr->dn->full_name);
break;
case OF_RECONFIG_ADD_PROPERTY:
case OF_RECONFIG_REMOVE_PROPERTY:
case OF_RECONFIG_UPDATE_PROPERTY:
+ case OF_RECONFIG_PRE_ADD_PROPERTY:
+ case OF_RECONFIG_PRE_REMOVE_PROPERTY:
+ case OF_RECONFIG_PRE_UPDATE_PROPERTY:
pr_debug("of/notify %-15s %s:%s\n", action_names[action],
pr->dn->full_name, pr->prop->name);
break;
@@ -141,6 +152,13 @@ int of_reconfig_get_state_change(unsigned long action, struct of_reconfig_data *
prop = pr->prop;
old_prop = pr->old_prop;
break;
+ /* no state change during pre-apply notifications */
+ case OF_RECONFIG_PRE_ATTACH_NODE:
+ case OF_RECONFIG_PRE_DETACH_NODE:
+ case OF_RECONFIG_PRE_ADD_PROPERTY:
+ case OF_RECONFIG_PRE_REMOVE_PROPERTY:
+ case OF_RECONFIG_PRE_UPDATE_PROPERTY:
+ return OF_RECONFIG_NO_CHANGE;
default:
return OF_RECONFIG_NO_CHANGE;
}
@@ -502,10 +520,31 @@ static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
}
}
-static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert)
+static unsigned long __of_changeset_entry_pre_action(unsigned long action)
+{
+ switch (action) {
+ case OF_RECONFIG_ATTACH_NODE:
+ return OF_RECONFIG_PRE_ATTACH_NODE;
+ case OF_RECONFIG_DETACH_NODE:
+ return OF_RECONFIG_PRE_DETACH_NODE;
+ case OF_RECONFIG_ADD_PROPERTY:
+ return OF_RECONFIG_PRE_ADD_PROPERTY;
+ case OF_RECONFIG_REMOVE_PROPERTY:
+ return OF_RECONFIG_PRE_REMOVE_PROPERTY;
+ case OF_RECONFIG_UPDATE_PROPERTY:
+ return OF_RECONFIG_PRE_UPDATE_PROPERTY;
+ }
+
+ /* this should not happen */
+ return action;
+}
+
+static int __of_changeset_entry_notify(struct of_changeset_entry *ce,
+ bool revert, bool pre)
{
struct of_reconfig_data rd;
struct of_changeset_entry ce_inverted;
+ unsigned long action;
int ret;
if (revert) {
@@ -513,26 +552,38 @@ static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool reve
ce = &ce_inverted;
}
- switch (ce->action) {
+ action = ce->action;
+ if (pre)
+ action = __of_changeset_entry_pre_action(action);
+
+ switch (action) {
case OF_RECONFIG_ATTACH_NODE:
case OF_RECONFIG_DETACH_NODE:
+ case OF_RECONFIG_PRE_DETACH_NODE:
+ case OF_RECONFIG_PRE_ATTACH_NODE:
memset(&rd, 0, sizeof(rd));
rd.dn = ce->np;
- ret = of_reconfig_notify(ce->action, &rd);
+ ret = of_reconfig_notify(action, &rd);
break;
case OF_RECONFIG_ADD_PROPERTY:
case OF_RECONFIG_REMOVE_PROPERTY:
case OF_RECONFIG_UPDATE_PROPERTY:
- ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop);
+ case OF_RECONFIG_PRE_REMOVE_PROPERTY:
+ case OF_RECONFIG_PRE_ADD_PROPERTY:
+ case OF_RECONFIG_PRE_UPDATE_PROPERTY:
+ ret = of_property_notify(action, ce->np, ce->prop,
+ ce->old_prop);
break;
default:
pr_err("%s: invalid devicetree changeset action: %i\n", __func__,
- (int)ce->action);
- return;
+ (int)action);
+ return -EINVAL;
}
if (ret)
pr_err("%s: notifier error @%s\n", __func__, ce->np->full_name);
+
+ return ret;
}
static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
@@ -687,7 +738,7 @@ int __of_changeset_apply(struct of_changeset *ocs)
/* drop the global lock while emitting notifiers */
mutex_unlock(&of_mutex);
list_for_each_entry(ce, &ocs->entries, node)
- __of_changeset_entry_notify(ce, 0);
+ __of_changeset_entry_notify(ce, 0, 0);
mutex_lock(&of_mutex);
pr_debug("of_changeset: notifiers sent.\n");
@@ -708,8 +759,16 @@ int __of_changeset_apply(struct of_changeset *ocs)
*/
int of_changeset_apply(struct of_changeset *ocs)
{
+ struct of_changeset_entry *ce;
int ret;
+ pr_debug("of_changeset: pre-apply notifiers.\n");
+ list_for_each_entry(ce, &ocs->entries, node) {
+ ret = __of_changeset_entry_notify(ce, 0, 1);
+ if (ret)
+ return ret;
+ }
+
mutex_lock(&of_mutex);
ret = __of_changeset_apply(ocs);
mutex_unlock(&of_mutex);
@@ -723,6 +782,10 @@ int __of_changeset_revert(struct of_changeset *ocs)
struct of_changeset_entry *ce;
int ret;
+ pr_debug("of_changeset: emitting pre-revert notifiers.\n");
+ list_for_each_entry_reverse(ce, &ocs->entries, node)
+ __of_changeset_entry_notify(ce, 1, 1);
+
pr_debug("of_changeset: reverting...\n");
list_for_each_entry_reverse(ce, &ocs->entries, node) {
ret = __of_changeset_entry_revert(ce);
@@ -738,7 +801,7 @@ int __of_changeset_revert(struct of_changeset *ocs)
/* drop the global lock while emitting notifiers */
mutex_unlock(&of_mutex);
list_for_each_entry_reverse(ce, &ocs->entries, node)
- __of_changeset_entry_notify(ce, 1);
+ __of_changeset_entry_notify(ce, 1, 0);
mutex_lock(&of_mutex);
pr_debug("of_changeset: notifiers sent.\n");
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index 8225081..9d0c0d9 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -53,13 +53,30 @@ struct of_overlay {
struct of_changeset cset;
};
+static int of_overlay_notify(unsigned long action, struct device_node *np,
+ struct property *prop, struct property *old_prop,
+ struct device_node *overlay)
+{
+ struct of_reconfig_data rd;
+
+ memset(&rd, 0, sizeof(rd));
+ rd.dn = np;
+ rd.prop = prop;
+ rd.old_prop = old_prop;
+ rd.overlay = overlay;
+ return of_reconfig_notify(action, &rd);
+}
+
static int of_overlay_apply_one(struct of_overlay *ov,
- struct device_node *target, const struct device_node *overlay);
+ struct device_node *target, struct device_node *overlay);
static int of_overlay_apply_single_property(struct of_overlay *ov,
- struct device_node *target, struct property *prop)
+ struct device_node *target, struct property *prop,
+ struct device_node *overlay)
{
struct property *propn, *tprop;
+ unsigned long action;
+ int ret;
/* NOTE: Multiple changes of single properties not supported */
tprop = of_find_property(target, prop->name, NULL);
@@ -74,6 +91,15 @@ static int of_overlay_apply_single_property(struct of_overlay *ov,
if (propn == NULL)
return -ENOMEM;
+ if (!tprop)
+ action = OF_RECONFIG_PRE_ADD_PROPERTY;
+ else
+ action = OF_RECONFIG_PRE_UPDATE_PROPERTY;
+
+ ret = of_overlay_notify(action, target, propn, tprop, overlay);
+ if (ret)
+ return ret;
+
/* not found? add */
if (tprop == NULL)
return of_changeset_add_property(&ov->cset, target, propn);
@@ -83,7 +109,8 @@ static int of_overlay_apply_single_property(struct of_overlay *ov,
}
static int of_overlay_apply_single_device_node(struct of_overlay *ov,
- struct device_node *target, struct device_node *child)
+ struct device_node *target, struct device_node *child,
+ struct device_node *overlay)
{
const char *cname;
struct device_node *tchild;
@@ -108,6 +135,11 @@ static int of_overlay_apply_single_device_node(struct of_overlay *ov,
/* point to parent */
tchild->parent = target;
+ ret = of_overlay_notify(OF_RECONFIG_PRE_ATTACH_NODE, tchild,
+ NULL, NULL, overlay);
+ if (ret)
+ return ret;
+
ret = of_changeset_attach_node(&ov->cset, tchild);
if (ret)
return ret;
@@ -128,14 +160,15 @@ static int of_overlay_apply_single_device_node(struct of_overlay *ov,
* by using the changeset.
*/
static int of_overlay_apply_one(struct of_overlay *ov,
- struct device_node *target, const struct device_node *overlay)
+ struct device_node *target, struct device_node *overlay)
{
struct device_node *child;
struct property *prop;
int ret;
for_each_property_of_node(overlay, prop) {
- ret = of_overlay_apply_single_property(ov, target, prop);
+ ret = of_overlay_apply_single_property(ov, target, prop,
+ overlay);
if (ret) {
pr_err("%s: Failed to apply prop @%s/%s\n",
__func__, target->full_name, prop->name);
@@ -144,7 +177,8 @@ static int of_overlay_apply_one(struct of_overlay *ov,
}
for_each_child_of_node(overlay, child) {
- ret = of_overlay_apply_single_device_node(ov, target, child);
+ ret = of_overlay_apply_single_device_node(ov, target, child,
+ overlay);
if (ret != 0) {
pr_err("%s: Failed to apply single node @%s/%s\n",
__func__, target->full_name,
diff --git a/include/linux/of.h b/include/linux/of.h
index dd10626..c350a26 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -79,6 +79,7 @@ struct of_reconfig_data {
struct device_node *dn;
struct property *prop;
struct property *old_prop;
+ struct device_node *overlay; /* only for pre-apply notify */
};
/* initialize a node */
@@ -350,6 +351,12 @@ extern int of_update_property(struct device_node *np, struct property *newprop);
#define OF_RECONFIG_ADD_PROPERTY 0x0003
#define OF_RECONFIG_REMOVE_PROPERTY 0x0004
#define OF_RECONFIG_UPDATE_PROPERTY 0x0005
+#define OF_RECONFIG_PRE_ATTACH_NODE 0x0006
+#define OF_RECONFIG_PRE_DETACH_NODE 0x0007
+#define OF_RECONFIG_PRE_ADD_PROPERTY 0x0008
+#define OF_RECONFIG_PRE_REMOVE_PROPERTY 0x0009
+#define OF_RECONFIG_PRE_UPDATE_PROPERTY 0x000a
+
extern int of_attach_node(struct device_node *);
extern int of_detach_node(struct device_node *);
--
1.7.9.5