From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7AD93C53219 for ; Wed, 29 Jul 2026 14:56:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=D0bt1o210iXmViyiyNbB4BNWFBk/sfgz+44p5RtjcWg=; b=vIeQe2lEkUWIr3QJ5KzMTspAy3 8qw6h2+A7N5hlZeTkj3SVpIBtEVlFdA21TGCts5U0/S9HWXVsHE9UzWWsxprcgDZdlmLqB24gH5nm laRVjDSM48vByedHHG7DFXYL/J1MuMQHvRSvfBz1rsKk7MJqpLn+HJKIRXDM+UKYV+gV5/K9iMxvw BcC02hwNpT1aFYLLGzty749HHtSDKLo5YK/eEPcWeVRCqBje3PLGDVk7Dx3Kcecpjt3v720E2cHuk uZSZ23covPlU2EKgGxizCsnGiEAdTE+6exy+u15F3BDOqft27n79GavHMIdGHOqOeLLp7c0B/aoB1 4ZGJh6XA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wp5iK-00000008JHc-1iEW; Wed, 29 Jul 2026 14:56:56 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wp5iI-00000008JFU-1MXW for kexec@lists.infradead.org; Wed, 29 Jul 2026 14:56:54 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id C0CB560A65; Wed, 29 Jul 2026 14:56:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D7141F00A3E; Wed, 29 Jul 2026 14:56:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785337013; bh=D0bt1o210iXmViyiyNbB4BNWFBk/sfgz+44p5RtjcWg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LWMlKbgRPxIR+JDr60bu3jSG9bGtGKUoDP0Huk78ZNntzaepLzQF/wAAZS5ml2L3Y htBlP8Lkyk2p9Fr63GxPeL9FCXbmxu7rOQ/a7av9kkDjYSxjVTJL0hv6YxeNuo3e8Z cpIb99H2zX8DEIadusffkWVx56B32TIwb6TUUcZcYf443f+K+yWXzCB5IQSqBqk6RM 2rCSxz81FYTEreXHdgZ6r/mHwsZzI8tqF0z5o8UBVSopFbF2F5wpgdSvcAOr/i8plb YGr/oXxrJcJ0UldE2lpEYWLw+pFvGGW/JMt9tMddjgm0gv1vkyUERmNStKp3lOecQA Pscqwjrm4k8oA== From: Pratyush Yadav To: Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Alexander Graf , Muchun Song , Oscar Salvador , David Hildenbrand , Andrew Morton , Jason Miu , Jork Loeser Cc: kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 12/22] kho: add kho_radix_init_tree() Date: Wed, 29 Jul 2026 16:55:57 +0200 Message-ID: <20260729145610.2827231-13-pratyush@kernel.org> X-Mailer: git-send-email 2.55.0.508.g3f0d502094-goog In-Reply-To: <20260729145610.2827231-1-pratyush@kernel.org> References: <20260729145610.2827231-1-pratyush@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org From: "Pratyush Yadav (Google)" Move the initialization logic of the radix tree into kho_radix_init_tree() instead of having users open-code it. Makes the boundaries cleaner and reduces code duplication when a new user of the radix tree will be added in a future commit. Signed-off-by: Pratyush Yadav (Google) --- include/linux/kho_radix_tree.h | 7 ++++ kernel/liveupdate/kexec_handover.c | 62 +++++++++++++++++++++--------- 2 files changed, 51 insertions(+), 18 deletions(-) diff --git a/include/linux/kho_radix_tree.h b/include/linux/kho_radix_tree.h index 66ca936b3f06..5d6ae2893684 100644 --- a/include/linux/kho_radix_tree.h +++ b/include/linux/kho_radix_tree.h @@ -54,6 +54,7 @@ int kho_radix_add_key(struct kho_radix_tree *tree, unsigned long key); void kho_radix_del_key(struct kho_radix_tree *tree, unsigned long key); int kho_radix_walk_tree(struct kho_radix_tree *tree, const struct kho_radix_walk_cb *cb, void *data); +int kho_radix_init_tree(struct kho_radix_tree *tree, struct kho_radix_node *root); void kho_radix_destroy_tree(struct kho_radix_tree *tree); #else /* #ifdef CONFIG_KEXEC_HANDOVER */ @@ -72,6 +73,12 @@ static inline int kho_radix_walk_tree(struct kho_radix_tree *tree, return -EOPNOTSUPP; } +static inline int kho_radix_init_tree(struct kho_radix_tree *tree, + struct kho_radix_node *root) +{ + return 0; +} + static inline void kho_radix_destroy_tree(struct kho_radix_tree *tree) { } #endif /* #ifdef CONFIG_KEXEC_HANDOVER */ diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c index 105dc0f3e691..04bfcbf9cc55 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -320,6 +320,30 @@ static void __kho_radix_destroy_tree(struct kho_radix_node *root, kho_radix_free_node(root); } +/** + * kho_radix_init_tree - initialize the radix tree. + * @tree: the tree to initialize. + * @root: root table of the radix tree. + * + * Initialize the radix tree with the given root node. If root is %NULL, an + * empty root table is allocated. If root is not %NULL, it is the caller's + * responsibility to make sure the root is valid and in the correct format. + * + * Return: 0 on success, -errno on failure. + */ +int kho_radix_init_tree(struct kho_radix_tree *tree, struct kho_radix_node *root) +{ + if (!root) + root = kho_radix_alloc_node(); + if (!root) + return -ENOMEM; + + tree->root = root; + mutex_init(&tree->lock); + return 0; +} +EXPORT_SYMBOL_GPL(kho_radix_init_tree); + /** * kho_radix_destroy_tree - Destroy the radix tree * @tree: The radix tree to destroy @@ -1499,18 +1523,23 @@ static void __init kho_mem_retrieve(void) * catches that and never sets kho_in.scratch_phys, which stops memory * retrieval. */ - kho_in.radix_tree.root = kho_get_mem_map(fdt); - mutex_init(&kho_in.radix_tree.lock); + err = kho_radix_init_tree(&kho_in.radix_tree, kho_get_mem_map(fdt)); + if (err) + goto err; err = kho_radix_walk_tree(&kho_in.radix_tree, &cb, NULL); - if (err) { - /* - * Failed to initialize preserved memory. Clear FDT and radix - * so KHO users don't treat it as a KHO boot. - */ - kho_in.fdt_phys = 0; - kho_in.radix_tree.root = NULL; - } + if (err) + goto err; + + return; + +err: + /* + * Failed to initialize preserved memory. Clear FDT and radix so KHO + * users don't treat it as a KHO boot. + */ + kho_in.fdt_phys = 0; + kho_in.radix_tree.root = NULL; } static __init int kho_out_fdt_setup(void) @@ -1636,16 +1665,14 @@ static __init int kho_init(void) if (!kho_enable) return 0; - tree->root = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!tree->root) { - err = -ENOMEM; + err = kho_radix_init_tree(tree, NULL); + if (err) goto err_free_scratch; - } kho_out.fdt = kho_alloc_preserve(PAGE_SIZE); if (IS_ERR(kho_out.fdt)) { err = PTR_ERR(kho_out.fdt); - goto err_free_kho_radix_tree_root; + goto err_free_kho_radix_tree; } err = kho_debugfs_init(); @@ -1696,9 +1723,8 @@ static __init int kho_init(void) err_free_fdt: kho_unpreserve_free(kho_out.fdt); -err_free_kho_radix_tree_root: - kfree(tree->root); - tree->root = NULL; +err_free_kho_radix_tree: + kho_radix_destroy_tree(tree); err_free_scratch: kho_out.fdt = NULL; for (int i = 0; i < kho_scratch_cnt; i++) { -- 2.55.0.508.g3f0d502094-goog