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 6CF77C54FCD for ; Sat, 1 Aug 2026 08:49:32 +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=qIP40ogFtBiVnUCuMm5h3Xm4LIuYWOirEQzH1R83Mew=; b=KcXQQkw6u7PJNsbezCz1AZvCHq eMBgL2FZZKK79lElnMEMAUm4YADJOUV37iZJnNs6GuPy+Qx6TYOF2dZuS+OMczYGxofoBpw/NPU5J fwQOCyijKhLxjevt5IIxlZDSZgSkUxQ5vcQaIA0MP9vY8+y7kyLnX3GQZPmIDjkDSW4qjaRxkzJqn 1ak/xpuI2Pc59cfb5xg/ixnuDHUPtOiA3b0/AiV6ATEUc7Nxg9AzoAxb8nVu/A4WpaTDO7I7Nywyf jFatIvp0qhQQ6by8SKscMQU+0OGopIn04KL6JUeKIf12xmr/7d1ZvyknYi46QSIsA67TtQeQWybVL 0eMehlxg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wq5PP-0000000E4tS-2do0; Sat, 01 Aug 2026 08:49:31 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wq5PO-0000000E4sA-2V49 for kexec@lists.infradead.org; Sat, 01 Aug 2026 08:49:30 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 1AEE44529C; Sat, 1 Aug 2026 08:49:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C09471F00ADF; Sat, 1 Aug 2026 08:49:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785574159; bh=qIP40ogFtBiVnUCuMm5h3Xm4LIuYWOirEQzH1R83Mew=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=JYbcsQdpPGh+2huXVDCcRwMp6Fu5lh3biUI41fTfLPX2V8yV5zvYxlXgf6NjueZzE 9T+5zCunRSXGJDmk2z+B61OjrHJ01KT4FZnQwShCshfMRs8wkOXIPPkqjkBcu4Gqsu 1WvyQ3G6Ds36kjcZIpzXUmgHVLFRT0e+P7h1EULlUA6aiTwhnmTlgQndsT8O5VVZlU Q6ttTzKP2s5TJfyZTdY91EkOJD/o2SRm/KPqo7dh9WXDEtAEcsdgMKIi7qGPHkv2YY g08jdCwyfxv7e4FhaKKWyfFpnlBCV2UwlaRDuOc0n+lEztHZ6KmPY5V/HfxIPeHOjn l78TX1nEtlHNw== 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 v6 11/22] kho: allow destroying KHO radix tree Date: Sat, 1 Aug 2026 10:48:20 +0200 Message-ID: <20260801084833.1897543-12-pratyush@kernel.org> X-Mailer: git-send-email 2.55.0.571.g244d577d93-goog In-Reply-To: <20260801084833.1897543-1-pratyush@kernel.org> References: <20260801084833.1897543-1-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)" Add kho_radix_destroy_tree() which allows destroying the radix tree and freeing all its pages. This is will be used by the upcoming scratch extension mechanism. It creates a radix tree to track free blocks and then frees them after telling memblock about them. Reviewed-by: Pasha Tatashin Signed-off-by: Pratyush Yadav (Google) --- include/linux/kho_radix_tree.h | 3 +++ kernel/liveupdate/kexec_handover.c | 35 ++++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+) diff --git a/include/linux/kho_radix_tree.h b/include/linux/kho_radix_tree.h index 60c1246a9101..b7532aff35d8 100644 --- a/include/linux/kho_radix_tree.h +++ b/include/linux/kho_radix_tree.h @@ -58,6 +58,7 @@ 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); +void kho_radix_destroy_tree(struct kho_radix_tree *tree); #else /* #ifdef CONFIG_KEXEC_HANDOVER */ @@ -75,6 +76,8 @@ static inline int kho_radix_walk_tree(struct kho_radix_tree *tree, return -EOPNOTSUPP; } +static inline void kho_radix_destroy_tree(struct kho_radix_tree *tree) { } + #endif /* #ifdef CONFIG_KEXEC_HANDOVER */ #endif /* _LINUX_KHO_RADIX_TREE_H */ diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c index a5800b960cf6..105dc0f3e691 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -301,6 +301,41 @@ void kho_radix_del_key(struct kho_radix_tree *tree, unsigned long key) } EXPORT_SYMBOL_GPL(kho_radix_del_key); +static void __kho_radix_destroy_tree(struct kho_radix_node *root, + unsigned int level) +{ + unsigned long i; + + if (level == 0) { + kho_radix_free_node(root); + return; + } + + for (i = 0; i < PAGE_SIZE / sizeof(phys_addr_t); i++) { + if (root->table[i]) + __kho_radix_destroy_tree(phys_to_virt(root->table[i]), + level - 1); + } + + kho_radix_free_node(root); +} + +/** + * kho_radix_destroy_tree - Destroy the radix tree + * @tree: The radix tree to destroy + * + * Walk @tree and free all its nodes. + */ +void kho_radix_destroy_tree(struct kho_radix_tree *tree) +{ + if (!tree->root) + return; + + __kho_radix_destroy_tree(tree->root, KHO_TREE_MAX_DEPTH - 1); + tree->root = NULL; +} +EXPORT_SYMBOL_GPL(kho_radix_destroy_tree); + static int kho_radix_walk_leaf(struct kho_radix_leaf *leaf, unsigned long key, const struct kho_radix_walk_cb *cb, void *data) { -- 2.55.0.571.g244d577d93-goog