diff options
Diffstat (limited to 'drivers/of/overlay.c')
| -rw-r--r-- | drivers/of/overlay.c | 1368 |
1 files changed, 1030 insertions, 338 deletions
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index c0e4ee1cd1ba..5b4f42230e6c 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -1,12 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Functions for working with device tree overlays * * Copyright (C) 2012 Pantelis Antoniou <panto@antoniou-consulting.com> * Copyright (C) 2012 Texas Instruments Inc. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * version 2 as published by the Free Software Foundation. */ #define pr_fmt(fmt) "OF: overlay: " fmt @@ -15,180 +12,510 @@ #include <linux/module.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/of_fdt.h> #include <linux/string.h> #include <linux/ctype.h> #include <linux/errno.h> #include <linux/slab.h> +#include <linux/libfdt.h> #include <linux/err.h> #include <linux/idr.h> #include "of_private.h" /** - * struct of_overlay_info - Holds a single overlay info - * @target: target of the overlay operation - * @overlay: pointer to the overlay contents node + * struct target - info about current target node as recursing through overlay + * @np: node where current level of overlay will be applied + * @in_livetree: @np is a node in the live devicetree * - * Holds a single overlay state, including all the overlay logs & - * records. + * Used in the algorithm to create the portion of a changeset that describes + * an overlay fragment, which is a devicetree subtree. Initially @np is a node + * in the live devicetree where the overlay subtree is targeted to be grafted + * into. When recursing to the next level of the overlay subtree, the target + * also recurses to the next level of the live devicetree, as long as overlay + * subtree node also exists in the live devicetree. When a node in the overlay + * subtree does not exist at the same level in the live devicetree, target->np + * points to a newly allocated node, and all subsequent targets in the subtree + * will be newly allocated nodes. */ -struct of_overlay_info { - struct device_node *target; +struct target { + struct device_node *np; + bool in_livetree; +}; + +/** + * struct fragment - info about fragment nodes in overlay expanded device tree + * @overlay: pointer to the __overlay__ node + * @target: target of the overlay operation + */ +struct fragment { struct device_node *overlay; + struct device_node *target; }; /** - * struct of_overlay - Holds a complete overlay transaction - * @node: List on which we are located - * @count: Count of ovinfo structures - * @ovinfo_tab: Overlay info table (count sized) - * @cset: Changeset to be used - * - * Holds a complete overlay transaction + * struct overlay_changeset + * @id: changeset identifier + * @ovcs_list: list on which we are located + * @new_fdt: Memory allocated to hold unflattened aligned FDT + * @overlay_mem: the memory chunk that contains @overlay_root + * @overlay_root: expanded device tree that contains the fragment nodes + * @notify_state: most recent notify action used on overlay + * @count: count of fragment structures + * @fragments: fragment nodes in the overlay expanded device tree + * @symbols_fragment: last element of @fragments[] is the __symbols__ node + * @cset: changeset to apply fragments to live device tree */ -struct of_overlay { +struct overlay_changeset { int id; - struct list_head node; + struct list_head ovcs_list; + const void *new_fdt; + const void *overlay_mem; + struct device_node *overlay_root; + enum of_overlay_notify_action notify_state; int count; - struct of_overlay_info *ovinfo_tab; + struct fragment *fragments; + bool symbols_fragment; struct of_changeset cset; }; -static int of_overlay_apply_one(struct of_overlay *ov, - struct device_node *target, const struct device_node *overlay); +/* flags are sticky - once set, do not reset */ +static int devicetree_state_flags; +#define DTSF_APPLY_FAIL 0x01 +#define DTSF_REVERT_FAIL 0x02 -static BLOCKING_NOTIFIER_HEAD(of_overlay_chain); +static int of_prop_val_eq(const struct property *p1, const struct property *p2) +{ + return p1->length == p2->length && + !memcmp(p1->value, p2->value, (size_t)p1->length); +} +/* + * If a changeset apply or revert encounters an error, an attempt will + * be made to undo partial changes, but may fail. If the undo fails + * we do not know the state of the devicetree. + */ +static int devicetree_corrupt(void) +{ + return devicetree_state_flags & + (DTSF_APPLY_FAIL | DTSF_REVERT_FAIL); +} + +static int build_changeset_next_level(struct overlay_changeset *ovcs, + struct target *target, const struct device_node *overlay_node); + +/* + * of_resolve_phandles() finds the largest phandle in the live tree. + * of_overlay_apply() may add a larger phandle to the live tree. + * Do not allow race between two overlays being applied simultaneously: + * mutex_lock(&of_overlay_phandle_mutex) + * of_resolve_phandles() + * of_overlay_apply() + * mutex_unlock(&of_overlay_phandle_mutex) + */ +static DEFINE_MUTEX(of_overlay_phandle_mutex); + +void of_overlay_mutex_lock(void) +{ + mutex_lock(&of_overlay_phandle_mutex); +} + +void of_overlay_mutex_unlock(void) +{ + mutex_unlock(&of_overlay_phandle_mutex); +} + +static LIST_HEAD(ovcs_list); +static DEFINE_IDR(ovcs_idr); + +static BLOCKING_NOTIFIER_HEAD(overlay_notify_chain); + +/** + * of_overlay_notifier_register() - Register notifier for overlay operations + * @nb: Notifier block to register + * + * Register for notification on overlay operations on device tree nodes. The + * reported actions defined by @of_reconfig_change. The notifier callback + * furthermore receives a pointer to the affected device tree node. + * + * Note that a notifier callback is not supposed to store pointers to a device + * tree node or its content beyond @OF_OVERLAY_POST_REMOVE corresponding to the + * respective node it received. + */ int of_overlay_notifier_register(struct notifier_block *nb) { - return blocking_notifier_chain_register(&of_overlay_chain, nb); + return blocking_notifier_chain_register(&overlay_notify_chain, nb); } EXPORT_SYMBOL_GPL(of_overlay_notifier_register); +/** + * of_overlay_notifier_unregister() - Unregister notifier for overlay operations + * @nb: Notifier block to unregister + */ int of_overlay_notifier_unregister(struct notifier_block *nb) { - return blocking_notifier_chain_unregister(&of_overlay_chain, nb); + return blocking_notifier_chain_unregister(&overlay_notify_chain, nb); } EXPORT_SYMBOL_GPL(of_overlay_notifier_unregister); -static int of_overlay_notify(struct of_overlay *ov, - enum of_overlay_notify_action action) +static int overlay_notify(struct overlay_changeset *ovcs, + enum of_overlay_notify_action action) { struct of_overlay_notify_data nd; int i, ret; - for (i = 0; i < ov->count; i++) { - struct of_overlay_info *ovinfo = &ov->ovinfo_tab[i]; + ovcs->notify_state = action; - nd.target = ovinfo->target; - nd.overlay = ovinfo->overlay; + for (i = 0; i < ovcs->count; i++) { + struct fragment *fragment = &ovcs->fragments[i]; - ret = blocking_notifier_call_chain(&of_overlay_chain, + nd.target = fragment->target; + nd.overlay = fragment->overlay; + + ret = blocking_notifier_call_chain(&overlay_notify_chain, action, &nd); - if (ret) - return notifier_to_errno(ret); + if (notifier_to_errno(ret)) { + ret = notifier_to_errno(ret); + pr_err("overlay changeset %s notifier error %d, target: %pOF\n", + of_overlay_action_name(action), ret, nd.target); + return ret; + } } return 0; } -static int of_overlay_apply_single_property(struct of_overlay *ov, - struct device_node *target, struct property *prop) +/* + * The values of properties in the "/__symbols__" node are paths in + * the ovcs->overlay_root. When duplicating the properties, the paths + * need to be adjusted to be the correct path for the live device tree. + * + * The paths refer to a node in the subtree of a fragment node's "__overlay__" + * node, for example "/fragment@0/__overlay__/symbol_path_tail", + * where symbol_path_tail can be a single node or it may be a multi-node path. + * + * The duplicated property value will be modified by replacing the + * "/fragment_name/__overlay/" portion of the value with the target + * path from the fragment node. + */ +static struct property *dup_and_fixup_symbol_prop( + struct overlay_changeset *ovcs, const struct property *prop) { - struct property *propn, *tprop; + struct fragment *fragment; + struct property *new_prop; + struct device_node *fragment_node; + struct device_node *overlay_node; + const char *path; + const char *path_tail; + const char *target_path; + int k; + int overlay_name_len; + int path_len; + int path_tail_len; + int target_path_len; + + if (!prop->value) + return NULL; + if (strnlen(prop->value, prop->length) >= prop->length) + return NULL; + path = prop->value; + path_len = strlen(path); + + if (path_len < 1) + return NULL; + fragment_node = __of_find_node_by_path(ovcs->overlay_root, path + 1); + overlay_node = __of_find_node_by_path(fragment_node, "__overlay__/"); + of_node_put(fragment_node); + of_node_put(overlay_node); + + for (k = 0; k < ovcs->count; k++) { + fragment = &ovcs->fragments[k]; + if (fragment->overlay == overlay_node) + break; + } + if (k >= ovcs->count) + return NULL; - /* NOTE: Multiple changes of single properties not supported */ - tprop = of_find_property(target, prop->name, NULL); + overlay_name_len = snprintf(NULL, 0, "%pOF", fragment->overlay); - /* special properties are not meant to be updated (silent NOP) */ - if (of_prop_cmp(prop->name, "name") == 0 || - of_prop_cmp(prop->name, "phandle") == 0 || - of_prop_cmp(prop->name, "linux,phandle") == 0) - return 0; + if (overlay_name_len > path_len) + return NULL; + path_tail = path + overlay_name_len; + path_tail_len = strlen(path_tail); - propn = __of_prop_dup(prop, GFP_KERNEL); - if (propn == NULL) - return -ENOMEM; + target_path = kasprintf(GFP_KERNEL, "%pOF", fragment->target); + if (!target_path) + return NULL; + target_path_len = strlen(target_path); + + new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL); + if (!new_prop) + goto err_free_target_path; + + new_prop->name = kstrdup(prop->name, GFP_KERNEL); + new_prop->length = target_path_len + path_tail_len + 1; + new_prop->value = kzalloc(new_prop->length, GFP_KERNEL); + if (!new_prop->name || !new_prop->value) + goto err_free_new_prop; + + strcpy(new_prop->value, target_path); + strcpy(new_prop->value + target_path_len, path_tail); - /* not found? add */ - if (tprop == NULL) - return of_changeset_add_property(&ov->cset, target, propn); + of_property_set_flag(new_prop, OF_DYNAMIC); - /* found? update */ - return of_changeset_update_property(&ov->cset, target, propn); + kfree(target_path); + + return new_prop; + +err_free_new_prop: + __of_prop_free(new_prop); +err_free_target_path: + kfree(target_path); + + return NULL; } -static int of_overlay_apply_single_device_node(struct of_overlay *ov, - struct device_node *target, struct device_node *child) +/** + * add_changeset_property() - add @overlay_prop to overlay changeset + * @ovcs: overlay changeset + * @target: where @overlay_prop will be placed + * @overlay_prop: property to add or update, from overlay tree + * @is_symbols_prop: 1 if @overlay_prop is from node "/__symbols__" + * + * If @overlay_prop does not already exist in live devicetree, add changeset + * entry to add @overlay_prop in @target, else add changeset entry to update + * value of @overlay_prop. + * + * @target may be either in the live devicetree or in a new subtree that + * is contained in the changeset. + * + * Some special properties are not added or updated (no error returned): + * "name", "phandle", "linux,phandle". + * + * Properties "#address-cells" and "#size-cells" are not updated if they + * are already in the live tree, but if present in the live tree, the values + * in the overlay must match the values in the live tree. + * + * Update of property in symbols node is not allowed. + * + * Return: 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if + * invalid @overlay. + */ +static int add_changeset_property(struct overlay_changeset *ovcs, + struct target *target, const struct property *overlay_prop, + bool is_symbols_prop) { - const char *cname; - struct device_node *tchild; + struct property *new_prop = NULL; + const struct property *prop; int ret = 0; - cname = kbasename(child->full_name); - if (cname == NULL) - return -ENOMEM; + if (target->in_livetree) + if (is_pseudo_property(overlay_prop->name)) + return 0; + + if (target->in_livetree) + prop = of_find_property(target->np, overlay_prop->name, NULL); + else + prop = NULL; + + if (prop) { + if (!of_prop_cmp(prop->name, "#address-cells")) { + if (!of_prop_val_eq(prop, overlay_prop)) { + pr_err("ERROR: changing value of #address-cells is not allowed in %pOF\n", + target->np); + ret = -EINVAL; + } + return ret; + + } else if (!of_prop_cmp(prop->name, "#size-cells")) { + if (!of_prop_val_eq(prop, overlay_prop)) { + pr_err("ERROR: changing value of #size-cells is not allowed in %pOF\n", + target->np); + ret = -EINVAL; + } + return ret; + } + } - /* NOTE: Multiple mods of created nodes not supported */ - tchild = of_get_child_by_name(target, cname); - if (tchild != NULL) { - /* new overlay phandle value conflicts with existing value */ - if (child->phandle) + if (is_symbols_prop) { + if (prop) return -EINVAL; + new_prop = dup_and_fixup_symbol_prop(ovcs, overlay_prop); + } else { + new_prop = __of_prop_dup(overlay_prop, GFP_KERNEL); + } - /* apply overlay recursively */ - ret = of_overlay_apply_one(ov, tchild, child); - of_node_put(tchild); + if (!new_prop) + return -ENOMEM; + + if (!prop) { + if (!target->in_livetree) { + new_prop->next = target->np->deadprops; + target->np->deadprops = new_prop; + } + ret = of_changeset_add_property(&ovcs->cset, target->np, + new_prop); } else { - /* create empty tree as a target */ - tchild = __of_node_dup(child, "%s/%s", target->full_name, cname); + ret = of_changeset_update_property(&ovcs->cset, target->np, + new_prop); + } + + if (!of_node_check_flag(target->np, OF_OVERLAY)) + pr_err("WARNING: memory leak will occur if overlay removed, property: %pOF/%s\n", + target->np, new_prop->name); + + if (ret) + __of_prop_free(new_prop); + return ret; +} + +/** + * add_changeset_node() - add @node (and children) to overlay changeset + * @ovcs: overlay changeset + * @target: where @node will be placed in live tree or changeset + * @node: node from within overlay device tree fragment + * + * If @node does not already exist in @target, add changeset entry + * to add @node in @target. + * + * If @node already exists in @target, and the existing node has + * a phandle, the overlay node is not allowed to have a phandle. + * + * If @node has child nodes, add the children recursively via + * build_changeset_next_level(). + * + * NOTE_1: A live devicetree created from a flattened device tree (FDT) will + * not contain the full path in node->full_name. Thus an overlay + * created from an FDT also will not contain the full path in + * node->full_name. However, a live devicetree created from Open + * Firmware may have the full path in node->full_name. + * + * add_changeset_node() follows the FDT convention and does not include + * the full path in node->full_name. Even though it expects the overlay + * to not contain the full path, it uses kbasename() to remove the + * full path should it exist. It also uses kbasename() in comparisons + * to nodes in the live devicetree so that it can apply an overlay to + * a live devicetree created from Open Firmware. + * + * NOTE_2: Multiple mods of created nodes not supported. + * + * Return: 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if + * invalid @overlay. + */ +static int add_changeset_node(struct overlay_changeset *ovcs, + struct target *target, const struct device_node *node) +{ + const char *node_kbasename; + const __be32 *phandle; + struct device_node *tchild; + struct target target_child; + int ret = 0, size; + + node_kbasename = kbasename(node->full_name); + + for_each_child_of_node(target->np, tchild) + if (!of_node_cmp(node_kbasename, kbasename(tchild->full_name))) + break; + + if (!tchild) { + tchild = __of_node_dup(NULL, node_kbasename); if (!tchild) return -ENOMEM; - /* point to parent */ - tchild->parent = target; + tchild->parent = target->np; + tchild->name = __of_get_property(node, "name", NULL); - ret = of_changeset_attach_node(&ov->cset, tchild); - if (ret) - return ret; + if (!tchild->name) + tchild->name = "<NULL>"; + + /* ignore obsolete "linux,phandle" */ + phandle = __of_get_property(node, "phandle", &size); + if (phandle && (size == 4)) + tchild->phandle = be32_to_cpup(phandle); - ret = of_overlay_apply_one(ov, tchild, child); + of_node_set_flag(tchild, OF_OVERLAY); + + ret = of_changeset_attach_node(&ovcs->cset, tchild); if (ret) return ret; + + target_child.np = tchild; + target_child.in_livetree = false; + + ret = build_changeset_next_level(ovcs, &target_child, node); + of_node_put(tchild); + return ret; } + if (node->phandle && tchild->phandle) { + ret = -EINVAL; + } else { + target_child.np = tchild; + target_child.in_livetree = target->in_livetree; + ret = build_changeset_next_level(ovcs, &target_child, node); + } + of_node_put(tchild); + return ret; } -/* - * Apply a single overlay node recursively. +/** + * build_changeset_next_level() - add level of overlay changeset + * @ovcs: overlay changeset + * @target: where to place @overlay_node in live tree + * @overlay_node: node from within an overlay device tree fragment + * + * Add the properties (if any) and nodes (if any) from @overlay_node to the + * @ovcs->cset changeset. If an added node has child nodes, they will + * be added recursively. + * + * Do not allow symbols node to have any children. * - * Note that the in case of an error the target node is left - * in a inconsistent state. Error recovery should be performed - * by using the changeset. + * Return: 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if + * invalid @overlay_node. */ -static int of_overlay_apply_one(struct of_overlay *ov, - struct device_node *target, const struct device_node *overlay) +static int build_changeset_next_level(struct overlay_changeset *ovcs, + struct target *target, const struct device_node *overlay_node) { - 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); + for_each_property_of_node(overlay_node, prop) { + ret = add_changeset_property(ovcs, target, prop, 0); + if (ret) { + pr_debug("Failed to apply prop @%pOF/%s, err=%d\n", + target->np, prop->name, ret); + return ret; + } + } + + for_each_child_of_node_scoped(overlay_node, child) { + ret = add_changeset_node(ovcs, target, child); if (ret) { - pr_err("Failed to apply prop @%s/%s\n", - target->full_name, prop->name); + pr_debug("Failed to apply node @%pOF/%pOFn, err=%d\n", + target->np, child, ret); return ret; } } - for_each_child_of_node(overlay, child) { - ret = of_overlay_apply_single_device_node(ov, target, child); - if (ret != 0) { - pr_err("Failed to apply single node @%s/%s\n", - target->full_name, child->name); - of_node_put(child); + return 0; +} + +/* + * Add the properties from __overlay__ node to the @ovcs->cset changeset. + */ +static int build_changeset_symbols_node(struct overlay_changeset *ovcs, + struct target *target, + const struct device_node *overlay_symbols_node) +{ + struct property *prop; + int ret; + + for_each_property_of_node(overlay_symbols_node, prop) { + ret = add_changeset_property(ovcs, target, prop, 1); + if (ret) { + pr_debug("Failed to apply symbols prop @%pOF/%s, err=%d\n", + target->np, prop->name, ret); return ret; } } @@ -196,300 +523,608 @@ static int of_overlay_apply_one(struct of_overlay *ov, return 0; } +static int find_dup_cset_node_entry(struct overlay_changeset *ovcs, + struct of_changeset_entry *ce_1) +{ + struct of_changeset_entry *ce_2; + char *fn_1, *fn_2; + int node_path_match; + + if (ce_1->action != OF_RECONFIG_ATTACH_NODE && + ce_1->action != OF_RECONFIG_DETACH_NODE) + return 0; + + ce_2 = ce_1; + list_for_each_entry_continue(ce_2, &ovcs->cset.entries, node) { + if ((ce_2->action != OF_RECONFIG_ATTACH_NODE && + ce_2->action != OF_RECONFIG_DETACH_NODE) || + of_node_cmp(ce_1->np->full_name, ce_2->np->full_name)) + continue; + + fn_1 = kasprintf(GFP_KERNEL, "%pOF", ce_1->np); + fn_2 = kasprintf(GFP_KERNEL, "%pOF", ce_2->np); + node_path_match = !fn_1 || !fn_2 || !strcmp(fn_1, fn_2); + kfree(fn_1); + kfree(fn_2); + if (node_path_match) { + pr_err("ERROR: multiple fragments add and/or delete node %pOF\n", + ce_1->np); + return -EINVAL; + } + } + + return 0; +} + +static int find_dup_cset_prop(struct overlay_changeset *ovcs, + struct of_changeset_entry *ce_1) +{ + struct of_changeset_entry *ce_2; + char *fn_1, *fn_2; + int node_path_match; + + if (ce_1->action != OF_RECONFIG_ADD_PROPERTY && + ce_1->action != OF_RECONFIG_REMOVE_PROPERTY && + ce_1->action != OF_RECONFIG_UPDATE_PROPERTY) + return 0; + + ce_2 = ce_1; + list_for_each_entry_continue(ce_2, &ovcs->cset.entries, node) { + if ((ce_2->action != OF_RECONFIG_ADD_PROPERTY && + ce_2->action != OF_RECONFIG_REMOVE_PROPERTY && + ce_2->action != OF_RECONFIG_UPDATE_PROPERTY) || + of_node_cmp(ce_1->np->full_name, ce_2->np->full_name)) + continue; + + fn_1 = kasprintf(GFP_KERNEL, "%pOF", ce_1->np); + fn_2 = kasprintf(GFP_KERNEL, "%pOF", ce_2->np); + node_path_match = !fn_1 || !fn_2 || !strcmp(fn_1, fn_2); + kfree(fn_1); + kfree(fn_2); + if (node_path_match && + !of_prop_cmp(ce_1->prop->name, ce_2->prop->name)) { + pr_err("ERROR: multiple fragments add, update, and/or delete property %pOF/%s\n", + ce_1->np, ce_1->prop->name); + return -EINVAL; + } + } + + return 0; +} + /** - * of_overlay_apply() - Apply @count overlays pointed at by @ovinfo_tab - * @ov: Overlay to apply + * changeset_dup_entry_check() - check for duplicate entries + * @ovcs: Overlay changeset + * + * Check changeset @ovcs->cset for multiple {add or delete} node entries for + * the same node or duplicate {add, delete, or update} properties entries + * for the same property. * - * Applies the overlays given, while handling all error conditions - * appropriately. Either the operation succeeds, or if it fails the - * live tree is reverted to the state before the attempt. - * Returns 0, or an error if the overlay attempt failed. + * Return: 0 on success, or -EINVAL if duplicate changeset entry found. */ -static int of_overlay_apply(struct of_overlay *ov) +static int changeset_dup_entry_check(struct overlay_changeset *ovcs) { - int i, err; + struct of_changeset_entry *ce_1; + int dup_entry = 0; - /* first we apply the overlays atomically */ - for (i = 0; i < ov->count; i++) { - struct of_overlay_info *ovinfo = &ov->ovinfo_tab[i]; + list_for_each_entry(ce_1, &ovcs->cset.entries, node) { + dup_entry |= find_dup_cset_node_entry(ovcs, ce_1); + dup_entry |= find_dup_cset_prop(ovcs, ce_1); + } + + return dup_entry ? -EINVAL : 0; +} - err = of_overlay_apply_one(ov, ovinfo->target, ovinfo->overlay); - if (err != 0) { - pr_err("apply failed '%s'\n", ovinfo->target->full_name); - return err; +/** + * build_changeset() - populate overlay changeset in @ovcs from @ovcs->fragments + * @ovcs: Overlay changeset + * + * Create changeset @ovcs->cset to contain the nodes and properties of the + * overlay device tree fragments in @ovcs->fragments[]. If an error occurs, + * any portions of the changeset that were successfully created will remain + * in @ovcs->cset. + * + * Return: 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if + * invalid overlay in @ovcs->fragments[]. + */ +static int build_changeset(struct overlay_changeset *ovcs) +{ + struct fragment *fragment; + struct target target; + int fragments_count, i, ret; + + /* + * if there is a symbols fragment in ovcs->fragments[i] it is + * the final element in the array + */ + if (ovcs->symbols_fragment) + fragments_count = ovcs->count - 1; + else + fragments_count = ovcs->count; + + for (i = 0; i < fragments_count; i++) { + fragment = &ovcs->fragments[i]; + + target.np = fragment->target; + target.in_livetree = true; + ret = build_changeset_next_level(ovcs, &target, + fragment->overlay); + if (ret) { + pr_debug("fragment apply failed '%pOF'\n", + fragment->target); + return ret; } } - return 0; + if (ovcs->symbols_fragment) { + fragment = &ovcs->fragments[ovcs->count - 1]; + + target.np = fragment->target; + target.in_livetree = true; + ret = build_changeset_symbols_node(ovcs, &target, + fragment->overlay); + if (ret) { + pr_debug("symbols fragment apply failed '%pOF'\n", + fragment->target); + return ret; + } + } + + return changeset_dup_entry_check(ovcs); } /* * Find the target node using a number of different strategies - * in order of preference + * in order of preference: * - * "target" property containing the phandle of the target - * "target-path" property containing the path of the target + * 1) "target" property containing the phandle of the target + * 2) "target-path" property containing the path of the target */ -static struct device_node *find_target_node(struct device_node *info_node) +static struct device_node *find_target(const struct device_node *info_node, + const struct device_node *target_base) { + struct device_node *node; + char *target_path; const char *path; u32 val; int ret; - /* first try to go by using the target as a phandle */ ret = of_property_read_u32(info_node, "target", &val); - if (ret == 0) - return of_find_node_by_phandle(val); + if (!ret) { + node = of_find_node_by_phandle(val); + if (!node) + pr_err("find target, node: %pOF, phandle 0x%x not found\n", + info_node, val); + return node; + } - /* now try to locate by path */ ret = of_property_read_string(info_node, "target-path", &path); - if (ret == 0) - return of_find_node_by_path(path); + if (!ret) { + if (target_base) { + target_path = kasprintf(GFP_KERNEL, "%pOF%s", target_base, path); + if (!target_path) + return NULL; + node = of_find_node_by_path(target_path); + if (!node) { + pr_err("find target, node: %pOF, path '%s' not found\n", + info_node, target_path); + } + kfree(target_path); + } else { + node = of_find_node_by_path(path); + if (!node) { + pr_err("find target, node: %pOF, path '%s' not found\n", + info_node, path); + } + } + return node; + } - pr_err("Failed to find target for node %p (%s)\n", - info_node, info_node->name); + pr_err("find target, node: %pOF, no target property\n", info_node); return NULL; } /** - * of_fill_overlay_info() - Fill an overlay info structure - * @ov Overlay to fill - * @info_node: Device node containing the overlay - * @ovinfo: Pointer to the overlay info structure to fill - * - * Fills an overlay info structure with the overlay information - * from a device node. This device node must have a target property - * which contains a phandle of the overlay target node, and an - * __overlay__ child node which has the overlay contents. - * Both ovinfo->target & ovinfo->overlay have their references taken. - * - * Returns 0 on success, or a negative error value. + * init_overlay_changeset() - initialize overlay changeset from overlay tree + * @ovcs: Overlay changeset to build + * @target_base: Point to the target node to apply overlay + * + * Initialize @ovcs. Populate @ovcs->fragments with node information from + * the top level of @overlay_root. The relevant top level nodes are the + * fragment nodes and the __symbols__ node. Any other top level node will + * be ignored. Populate other @ovcs fields. + * + * Return: 0 on success, -ENOMEM if memory allocation failure, -EINVAL if error + * detected in @overlay_root. On error return, the caller of + * init_overlay_changeset() must call free_overlay_changeset(). */ -static int of_fill_overlay_info(struct of_overlay *ov, - struct device_node *info_node, struct of_overlay_info *ovinfo) +static int init_overlay_changeset(struct overlay_changeset *ovcs, + const struct device_node *target_base) { - ovinfo->overlay = of_get_child_by_name(info_node, "__overlay__"); - if (ovinfo->overlay == NULL) - goto err_fail; - - ovinfo->target = find_target_node(info_node); - if (ovinfo->target == NULL) - goto err_fail; + struct device_node *node, *overlay_node; + struct fragment *fragment; + struct fragment *fragments; + int cnt, ret; + + /* + * None of the resources allocated by this function will be freed in + * the error paths. Instead the caller of this function is required + * to call free_overlay_changeset() (which will free the resources) + * if error return. + */ + + /* + * 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(ovcs->overlay_root, OF_DYNAMIC)) + pr_debug("%s() ovcs->overlay_root is not dynamic\n", __func__); + + if (!of_node_check_flag(ovcs->overlay_root, OF_DETACHED)) + pr_debug("%s() ovcs->overlay_root is not detached\n", __func__); + + if (!of_node_is_root(ovcs->overlay_root)) + pr_debug("%s() ovcs->overlay_root is not root\n", __func__); - return 0; + cnt = 0; -err_fail: - of_node_put(ovinfo->target); - of_node_put(ovinfo->overlay); + /* fragment nodes */ + for_each_child_of_node(ovcs->overlay_root, node) { + overlay_node = of_get_child_by_name(node, "__overlay__"); + if (overlay_node) { + cnt++; + of_node_put(overlay_node); + } + } - memset(ovinfo, 0, sizeof(*ovinfo)); - return -EINVAL; -} + node = of_get_child_by_name(ovcs->overlay_root, "__symbols__"); + if (node) { + cnt++; + of_node_put(node); + } -/** - * of_build_overlay_info() - Build an overlay info array - * @ov Overlay to build - * @tree: Device node containing all the overlays - * - * Helper function that given a tree containing overlay information, - * allocates and builds an overlay info array containing it, ready - * for use using of_overlay_apply. - * - * Returns 0 on success with the @cntp @ovinfop pointers valid, - * while on error a negative error value is returned. - */ -static int of_build_overlay_info(struct of_overlay *ov, - struct device_node *tree) -{ - struct device_node *node; - struct of_overlay_info *ovinfo; - int cnt, err; + fragments = kcalloc(cnt, sizeof(*fragments), GFP_KERNEL); + if (!fragments) { + ret = -ENOMEM; + goto err_out; + } + ovcs->fragments = fragments; - /* worst case; every child is a node */ cnt = 0; - for_each_child_of_node(tree, node) + for_each_child_of_node(ovcs->overlay_root, node) { + overlay_node = of_get_child_by_name(node, "__overlay__"); + if (!overlay_node) + continue; + + fragment = &fragments[cnt]; + fragment->overlay = overlay_node; + fragment->target = find_target(node, target_base); + if (!fragment->target) { + of_node_put(fragment->overlay); + ret = -EINVAL; + of_node_put(node); + goto err_out; + } + cnt++; + } - ovinfo = kcalloc(cnt, sizeof(*ovinfo), GFP_KERNEL); - if (ovinfo == NULL) - return -ENOMEM; + /* + * if there is a symbols fragment in ovcs->fragments[i] it is + * the final element in the array + */ + node = of_get_child_by_name(ovcs->overlay_root, "__symbols__"); + if (node) { + ovcs->symbols_fragment = 1; + fragment = &fragments[cnt]; + fragment->overlay = node; + fragment->target = of_find_node_by_path("/__symbols__"); + + if (!fragment->target) { + pr_err("symbols in overlay, but not in live tree\n"); + ret = -EINVAL; + of_node_put(node); + goto err_out; + } - cnt = 0; - for_each_child_of_node(tree, node) { - err = of_fill_overlay_info(ov, node, &ovinfo[cnt]); - if (err == 0) - cnt++; + cnt++; } - /* if nothing filled, return error */ - if (cnt == 0) { - kfree(ovinfo); - return -ENODEV; + if (!cnt) { + pr_err("no fragments or symbols in overlay\n"); + ret = -EINVAL; + goto err_out; } - ov->count = cnt; - ov->ovinfo_tab = ovinfo; + ovcs->count = cnt; return 0; + +err_out: + pr_err("%s() failed, ret = %d\n", __func__, ret); + + return ret; } -/** - * of_free_overlay_info() - Free an overlay info array - * @ov Overlay to free the overlay info from - * @ovinfo_tab: Array of overlay_info's to free - * - * Releases the memory of a previously allocated ovinfo array - * by of_build_overlay_info. - * Returns 0, or an error if the arguments are bogus. - */ -static int of_free_overlay_info(struct of_overlay *ov) +static void free_overlay_changeset(struct overlay_changeset *ovcs) { - struct of_overlay_info *ovinfo; int i; - /* do it in reverse */ - for (i = ov->count - 1; i >= 0; i--) { - ovinfo = &ov->ovinfo_tab[i]; + if (ovcs->cset.entries.next) + of_changeset_destroy(&ovcs->cset); - of_node_put(ovinfo->target); - of_node_put(ovinfo->overlay); + if (ovcs->id) { + idr_remove(&ovcs_idr, ovcs->id); + list_del(&ovcs->ovcs_list); + ovcs->id = 0; } - kfree(ov->ovinfo_tab); - return 0; -} -static LIST_HEAD(ov_list); -static DEFINE_IDR(ov_idr); + for (i = 0; i < ovcs->count; i++) { + of_node_put(ovcs->fragments[i].target); + of_node_put(ovcs->fragments[i].overlay); + } + kfree(ovcs->fragments); + + /* + * There should be no live pointers into ovcs->overlay_mem and + * ovcs->new_fdt due to the policy that overlay notifiers are not + * allowed to retain pointers into the overlay devicetree other + * than during the window from OF_OVERLAY_PRE_APPLY overlay + * notifiers until the OF_OVERLAY_POST_REMOVE overlay notifiers. + * + * A memory leak will occur here if within the window. + */ + + if (ovcs->notify_state == OF_OVERLAY_INIT || + ovcs->notify_state == OF_OVERLAY_POST_REMOVE) { + kfree(ovcs->overlay_mem); + kfree(ovcs->new_fdt); + } + kfree(ovcs); +} -/** - * of_overlay_create() - Create and apply an overlay - * @tree: Device node containing all the overlays +/* + * internal documentation + * + * of_overlay_apply() - Create and apply an overlay changeset + * @ovcs: overlay changeset + * @base: point to the target node to apply overlay + * + * Creates and applies an overlay changeset. + * + * If an error is returned by an overlay changeset pre-apply notifier + * then no further overlay changeset pre-apply notifier will be called. + * + * If an error is returned by an overlay changeset post-apply notifier + * then no further overlay changeset post-apply notifier will be called. * - * Creates and applies an overlay while also keeping track - * of the overlay in a list. This list can be used to prevent - * illegal overlay removals. + * If more than one notifier returns an error, then the last notifier + * error to occur is returned. * - * Returns the id of the created overlay, or a negative error number + * If an error occurred while applying the overlay changeset, then an + * attempt is made to revert any changes that were made to the + * device tree. If there were any errors during the revert attempt + * then the state of the device tree can not be determined, and any + * following attempt to apply or remove an overlay changeset will be + * refused. + * + * Returns 0 on success, or a negative error number. On error return, + * the caller of of_overlay_apply() must call free_overlay_changeset(). */ -int of_overlay_create(struct device_node *tree) + +static int of_overlay_apply(struct overlay_changeset *ovcs, + const struct device_node *base) { - struct of_overlay *ov; - int err, id; + int ret = 0, ret_revert, ret_tmp; - /* allocate the overlay structure */ - ov = kzalloc(sizeof(*ov), GFP_KERNEL); - if (ov == NULL) - return -ENOMEM; - ov->id = -1; + ret = of_resolve_phandles(ovcs->overlay_root); + if (ret) + goto out; - INIT_LIST_HEAD(&ov->node); + ret = init_overlay_changeset(ovcs, base); + if (ret) + goto out; - of_changeset_init(&ov->cset); + ret = overlay_notify(ovcs, OF_OVERLAY_PRE_APPLY); + if (ret) + goto out; - mutex_lock(&of_mutex); + ret = build_changeset(ovcs); + if (ret) + goto out; - id = idr_alloc(&ov_idr, ov, 0, 0, GFP_KERNEL); - if (id < 0) { - err = id; - goto err_destroy_trans; + ret_revert = 0; + ret = __of_changeset_apply_entries(&ovcs->cset, &ret_revert); + if (ret) { + if (ret_revert) { + pr_debug("overlay changeset revert error %d\n", + ret_revert); + devicetree_state_flags |= DTSF_APPLY_FAIL; + } + goto out; } - ov->id = id; - /* build the overlay info structures */ - err = of_build_overlay_info(ov, tree); - if (err) { - pr_err("of_build_overlay_info() failed for tree@%s\n", - tree->full_name); - goto err_free_idr; + ret = __of_changeset_apply_notify(&ovcs->cset); + if (ret) + pr_err("overlay apply changeset entry notify error %d\n", ret); + /* notify failure is not fatal, continue */ + + ret_tmp = overlay_notify(ovcs, OF_OVERLAY_POST_APPLY); + if (ret_tmp) + if (!ret) + ret = ret_tmp; + +out: + pr_debug("%s() err=%d\n", __func__, ret); + + return ret; +} + +/** + * of_overlay_fdt_apply() - Create and apply an overlay changeset + * @overlay_fdt: pointer to overlay FDT + * @overlay_fdt_size: number of bytes in @overlay_fdt + * @ret_ovcs_id: pointer for returning created changeset id + * @base: pointer for the target node to apply overlay + * + * Creates and applies an overlay changeset. + * + * See of_overlay_apply() for important behavior information. + * + * Return: 0 on success, or a negative error number. *@ret_ovcs_id is set to + * the value of overlay changeset id, which can be passed to of_overlay_remove() + * to remove the overlay. + * + * On error return, the changeset may be partially applied. This is especially + * likely if an OF_OVERLAY_POST_APPLY notifier returns an error. In this case + * the caller should call of_overlay_remove() with the value in *@ret_ovcs_id. + */ + +int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size, + int *ret_ovcs_id, const struct device_node *base) +{ + void *new_fdt; + void *new_fdt_align; + void *overlay_mem; + int ret; + u32 size; + struct overlay_changeset *ovcs; + + *ret_ovcs_id = 0; + + if (devicetree_corrupt()) { + pr_err("devicetree state suspect, refuse to apply overlay\n"); + return -EBUSY; } - err = of_overlay_notify(ov, OF_OVERLAY_PRE_APPLY); - if (err < 0) { - pr_err("%s: Pre-apply notifier failed (err=%d)\n", - __func__, err); - goto err_free_idr; + if (overlay_fdt_size < sizeof(struct fdt_header) || + fdt_check_header(overlay_fdt)) { + pr_err("Invalid overlay_fdt header\n"); + return -EINVAL; } - /* apply the overlay */ - err = of_overlay_apply(ov); - if (err) - goto err_abort_trans; + size = fdt_totalsize(overlay_fdt); + if (overlay_fdt_size < size) + return -EINVAL; - /* apply the changeset */ - err = __of_changeset_apply(&ov->cset); - if (err) - goto err_revert_overlay; + ovcs = kzalloc(sizeof(*ovcs), GFP_KERNEL); + if (!ovcs) + return -ENOMEM; + of_overlay_mutex_lock(); + mutex_lock(&of_mutex); - /* add to the tail of the overlay list */ - list_add_tail(&ov->node, &ov_list); + /* + * ovcs->notify_state must be set to OF_OVERLAY_INIT before allocating + * ovcs resources, implicitly set by kzalloc() of ovcs + */ - of_overlay_notify(ov, OF_OVERLAY_POST_APPLY); + ovcs->id = idr_alloc(&ovcs_idr, ovcs, 1, 0, GFP_KERNEL); + if (ovcs->id <= 0) { + ret = ovcs->id; + goto err_free_ovcs; + } - mutex_unlock(&of_mutex); + INIT_LIST_HEAD(&ovcs->ovcs_list); + list_add_tail(&ovcs->ovcs_list, &ovcs_list); + of_changeset_init(&ovcs->cset); + + /* + * Must create permanent copy of FDT because of_fdt_unflatten_tree() + * will create pointers to the passed in FDT in the unflattened tree. + */ + new_fdt = kmalloc(size + FDT_ALIGN_SIZE, GFP_KERNEL); + if (!new_fdt) { + ret = -ENOMEM; + goto err_free_ovcs; + } + ovcs->new_fdt = new_fdt; - return id; + new_fdt_align = PTR_ALIGN(new_fdt, FDT_ALIGN_SIZE); + memcpy(new_fdt_align, overlay_fdt, size); -err_revert_overlay: -err_abort_trans: - of_free_overlay_info(ov); -err_free_idr: - idr_remove(&ov_idr, ov->id); -err_destroy_trans: - of_changeset_destroy(&ov->cset); - kfree(ov); + overlay_mem = of_fdt_unflatten_tree(new_fdt_align, NULL, + &ovcs->overlay_root); + if (!overlay_mem) { + pr_err("unable to unflatten overlay_fdt\n"); + ret = -EINVAL; + goto err_free_ovcs; + } + ovcs->overlay_mem = overlay_mem; + + ret = of_overlay_apply(ovcs, base); + /* + * If of_overlay_apply() error, calling free_overlay_changeset() may + * result in a memory leak if the apply partly succeeded, so do NOT + * goto err_free_ovcs. Instead, the caller of of_overlay_fdt_apply() + * can call of_overlay_remove(); + */ + *ret_ovcs_id = ovcs->id; + goto out_unlock; + +err_free_ovcs: + free_overlay_changeset(ovcs); + +out_unlock: mutex_unlock(&of_mutex); - - return err; + of_overlay_mutex_unlock(); + return ret; } -EXPORT_SYMBOL_GPL(of_overlay_create); +EXPORT_SYMBOL_GPL(of_overlay_fdt_apply); -/* check whether the given node, lies under the given tree */ -static int overlay_subtree_check(struct device_node *tree, - struct device_node *dn) +/* + * Find @np in @tree. + * + * Returns 1 if @np is @tree or is contained in @tree, else 0 + */ +static int find_node(const struct device_node *tree, struct device_node *np) { - struct device_node *child; - - /* match? */ - if (tree == dn) + if (tree == np) return 1; - for_each_child_of_node(tree, child) { - if (overlay_subtree_check(child, dn)) { - of_node_put(child); + for_each_child_of_node_scoped(tree, child) { + if (find_node(child, np)) return 1; - } } return 0; } -/* check whether this overlay is the topmost */ -static int overlay_is_topmost(struct of_overlay *ov, struct device_node *dn) +/* + * Is @remove_ce_node a child of, a parent of, or the same as any + * node in an overlay changeset more topmost than @remove_ovcs? + * + * Returns 1 if found, else 0 + */ +static int node_overlaps_later_cs(struct overlay_changeset *remove_ovcs, + struct device_node *remove_ce_node) { - struct of_overlay *ovt; + struct overlay_changeset *ovcs; struct of_changeset_entry *ce; - list_for_each_entry_reverse(ovt, &ov_list, node) { - /* if we hit ourselves, we're done */ - if (ovt == ov) + list_for_each_entry_reverse(ovcs, &ovcs_list, ovcs_list) { + if (ovcs == remove_ovcs) break; - /* check against each subtree affected by this overlay */ - list_for_each_entry(ce, &ovt->cset.entries, node) { - if (overlay_subtree_check(ce->np, dn)) { - pr_err("%s: #%d clashes #%d @%s\n", - __func__, ov->id, ovt->id, - dn->full_name); - return 0; + list_for_each_entry(ce, &ovcs->cset.entries, node) { + if (find_node(ce->np, remove_ce_node)) { + pr_err("%s: #%d overlaps with #%d @%pOF\n", + __func__, remove_ovcs->id, ovcs->id, + remove_ce_node); + return 1; + } + if (find_node(remove_ce_node, ce->np)) { + pr_err("%s: #%d overlaps with #%d @%pOF\n", + __func__, remove_ovcs->id, ovcs->id, + remove_ce_node); + return 1; } } } - /* overlay is topmost */ - return 1; + return 0; } /* @@ -500,15 +1135,15 @@ static int overlay_is_topmost(struct of_overlay *ov, struct device_node *dn) * The topmost check is done by exploiting this property. For each * affected device node in the log list we check if this overlay is * the one closest to the tail. If another overlay has affected this - * device node and is closest to the tail, then removal is not permited. + * device node and is closest to the tail, then removal is not permitted. */ -static int overlay_removal_is_ok(struct of_overlay *ov) +static int overlay_removal_is_ok(struct overlay_changeset *remove_ovcs) { - struct of_changeset_entry *ce; + struct of_changeset_entry *remove_ce; - list_for_each_entry(ce, &ov->cset.entries, node) { - if (!overlay_is_topmost(ov, ce->np)) { - pr_err("overlay #%d is not topmost\n", ov->id); + list_for_each_entry(remove_ce, &remove_ovcs->cset.entries, node) { + if (node_overlaps_later_cs(remove_ovcs, remove_ce->np)) { + pr_err("overlay #%d is not topmost\n", remove_ovcs->id); return 0; } } @@ -517,75 +1152,132 @@ static int overlay_removal_is_ok(struct of_overlay *ov) } /** - * of_overlay_destroy() - Removes an overlay - * @id: Overlay id number returned by a previous call to of_overlay_create + * of_overlay_remove() - Revert and free an overlay changeset + * @ovcs_id: Pointer to overlay changeset id + * + * Removes an overlay if it is permissible. @ovcs_id was previously returned + * by of_overlay_fdt_apply(). + * + * If an error occurred while attempting to revert the overlay changeset, + * then an attempt is made to re-apply any changeset entry that was + * reverted. If an error occurs on re-apply then the state of the device + * tree can not be determined, and any following attempt to apply or remove + * an overlay changeset will be refused. + * + * A non-zero return value will not revert the changeset if error is from: + * - parameter checks + * - overlay changeset pre-remove notifier + * - overlay changeset entry revert * - * Removes an overlay if it is permissible. + * If an error is returned by an overlay changeset pre-remove notifier + * then no further overlay changeset pre-remove notifier will be called. * - * Returns 0 on success, or a negative error number + * If more than one notifier returns an error, then the last notifier + * error to occur is returned. + * + * A non-zero return value will revert the changeset if error is from: + * - overlay changeset entry notifier + * - overlay changeset post-remove notifier + * + * If an error is returned by an overlay changeset post-remove notifier + * then no further overlay changeset post-remove notifier will be called. + * + * Return: 0 on success, or a negative error number. *@ovcs_id is set to + * zero after reverting the changeset, even if a subsequent error occurs. */ -int of_overlay_destroy(int id) +int of_overlay_remove(int *ovcs_id) { - struct of_overlay *ov; - int err; + struct overlay_changeset *ovcs; + int ret, ret_apply, ret_tmp; - mutex_lock(&of_mutex); + if (*ovcs_id == 0) + return 0; - ov = idr_find(&ov_idr, id); - if (ov == NULL) { - err = -ENODEV; - pr_err("destroy: Could not find overlay #%d\n", id); + if (devicetree_corrupt()) { + pr_err("suspect devicetree state, refuse to remove overlay\n"); + ret = -EBUSY; goto out; } - /* check whether the overlay is safe to remove */ - if (!overlay_removal_is_ok(ov)) { - err = -EBUSY; - goto out; + mutex_lock(&of_mutex); + + ovcs = idr_find(&ovcs_idr, *ovcs_id); + if (!ovcs) { + ret = -ENODEV; + pr_err("remove: Could not find overlay #%d\n", *ovcs_id); + goto err_unlock; } - of_overlay_notify(ov, OF_OVERLAY_PRE_REMOVE); - list_del(&ov->node); - __of_changeset_revert(&ov->cset); - of_overlay_notify(ov, OF_OVERLAY_POST_REMOVE); - of_free_overlay_info(ov); - idr_remove(&ov_idr, id); - of_changeset_destroy(&ov->cset); - kfree(ov); + if (!overlay_removal_is_ok(ovcs)) { + ret = -EBUSY; + goto err_unlock; + } - err = 0; + ret = overlay_notify(ovcs, OF_OVERLAY_PRE_REMOVE); + if (ret) + goto err_unlock; -out: + ret_apply = 0; + ret = __of_changeset_revert_entries(&ovcs->cset, &ret_apply); + if (ret) { + if (ret_apply) + devicetree_state_flags |= DTSF_REVERT_FAIL; + goto err_unlock; + } + + ret = __of_changeset_revert_notify(&ovcs->cset); + if (ret) + pr_err("overlay remove changeset entry notify error %d\n", ret); + /* notify failure is not fatal, continue */ + + *ovcs_id = 0; + + /* + * Note that the overlay memory will be kfree()ed by + * free_overlay_changeset() even if the notifier for + * OF_OVERLAY_POST_REMOVE returns an error. + */ + ret_tmp = overlay_notify(ovcs, OF_OVERLAY_POST_REMOVE); + if (ret_tmp) + if (!ret) + ret = ret_tmp; + + free_overlay_changeset(ovcs); + +err_unlock: + /* + * If jumped over free_overlay_changeset(), then did not kfree() + * overlay related memory. This is a memory leak unless a subsequent + * of_overlay_remove() of this overlay is successful. + */ mutex_unlock(&of_mutex); - return err; +out: + pr_debug("%s() err=%d\n", __func__, ret); + + return ret; } -EXPORT_SYMBOL_GPL(of_overlay_destroy); +EXPORT_SYMBOL_GPL(of_overlay_remove); /** - * of_overlay_destroy_all() - Removes all overlays from the system + * of_overlay_remove_all() - Reverts and frees all overlay changesets * * Removes all overlays from the system in the correct order. * - * Returns 0 on success, or a negative error number + * Return: 0 on success, or a negative error number */ -int of_overlay_destroy_all(void) +int of_overlay_remove_all(void) { - struct of_overlay *ov, *ovn; - - mutex_lock(&of_mutex); + struct overlay_changeset *ovcs, *ovcs_n; + int ret; /* the tail of list is guaranteed to be safe to remove */ - list_for_each_entry_safe_reverse(ov, ovn, &ov_list, node) { - list_del(&ov->node); - __of_changeset_revert(&ov->cset); - of_free_overlay_info(ov); - idr_remove(&ov_idr, ov->id); - kfree(ov); + list_for_each_entry_safe_reverse(ovcs, ovcs_n, &ovcs_list, ovcs_list) { + ret = of_overlay_remove(&ovcs->id); + if (ret) + return ret; } - mutex_unlock(&of_mutex); - return 0; } -EXPORT_SYMBOL_GPL(of_overlay_destroy_all); +EXPORT_SYMBOL_GPL(of_overlay_remove_all); |