From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 98EDE1A6802; Thu, 28 May 2026 00:42:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779928944; cv=none; b=FLJPP7kGKPNwZe+2gkk0nVgzcWqey+fLxQ4zZRNiIBLdKN540Cf85V28NTLpNv4HOKIKEAA5/bhEPdc7TEjtpX/aaGMZPSsBmZ6uOdR+Hin5ZEfdb8a8LoRF3B4LGLZ0lomH5QyouVhGHZ8B1Nwlxfv45E8eReWpx0NmdXkAC+k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779928944; c=relaxed/simple; bh=GL1ar8UMiWXdIZy7N+aq6Q99SWjeAFlqu87PW9Ik/GQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lJbI6H+CkRJqD4UGIpz5SZQN2vUTa/gB7I4p/3IQCtk32wIUVYSLsQ7gPq7yuaVtjAU8WqzwrQ8c4JXRochllfF9yslQbf2VlAwX8ljpay4BFByF183sq9EkzTlpr5JPc8D9EzNZpoUyNl8YlrGclG8Er2FCm5UTbs3tU18xRNk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=aNqit3KB; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="aNqit3KB" Received: by linux.microsoft.com (Postfix, from userid 1241) id DC63D20B7171; Wed, 27 May 2026 17:42:11 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com DC63D20B7171 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1779928931; bh=Qtg35L2q2xRwHSsKrclbmv4EHz2zvqSPWUg8lI/YDVA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aNqit3KBt4dgCNj9E3c4pYnMmdEvIVLUR3/gOZSHXCYL/I3Gx9eMtb11nZR64Eef0 xgBMel7G/URxjTi/UfsmeYswamWChWlVND5cNvDETyd40iea1PcZyXwl0K9jUhbObC BlXMq6HkC4/uWZNGKU2mwWcu24FF1YZZQSFHqMRI= From: Jork Loeser To: linux-hyperv@vger.kernel.org, linux-mm@kvack.org, kexec@lists.infradead.org Cc: "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Alexander Graf , Jason Miu , Andrew Morton , David Hildenbrand , Muchun Song , Oscar Salvador , Baoquan He , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Kees Cook , Ran Xiaokai , Justinien Bouron , Sourabh Jain , Pingfan Liu , "Rafael J. Wysocki" , Mario Limonciello , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-kernel@vger.kernel.org, Michael Kelley , Jork Loeser Subject: [RFC PATCH 03/20] kho: add a struct for radix callbacks Date: Wed, 27 May 2026 17:41:45 -0700 Message-ID: <20260528004204.1484584-4-jloeser@linux.microsoft.com> X-Mailer: git-send-email 2.43.7 In-Reply-To: <20260528004204.1484584-1-jloeser@linux.microsoft.com> References: <20260528004204.1484584-1-jloeser@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Pratyush Yadav (Google)" A future commit will add more callbacks for the KHO radix tree. Add a struct for collecting the callbacks. Signed-off-by: Pratyush Yadav (Google) Signed-off-by: Jork Loeser --- include/linux/kho_radix_tree.h | 15 ++++++++++++--- kernel/liveupdate/kexec_handover.c | 29 ++++++++++++++++------------- 2 files changed, 28 insertions(+), 16 deletions(-) diff --git a/include/linux/kho_radix_tree.h b/include/linux/kho_radix_tree.h index f368f3b9f923..030da6399d28 100644 --- a/include/linux/kho_radix_tree.h +++ b/include/linux/kho_radix_tree.h @@ -34,14 +34,23 @@ struct kho_radix_tree { struct mutex lock; /* protects the tree's structure and root pointer */ }; -typedef int (*kho_radix_tree_walk_callback_t)(unsigned long key); +/** + * struct kho_radix_walk_cb - Callbacks for KHO radix tree walk. + * @key: Called on each present key in the radix tree. + * + * For each callback, a return value of 0 continues the walk and a non-zero + * return value is directly returned to the caller. + */ +struct kho_radix_walk_cb { + int (*key)(unsigned long key); +}; #ifdef CONFIG_KEXEC_HANDOVER 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, - kho_radix_tree_walk_callback_t cb); + const struct kho_radix_walk_cb *cb); #else /* #ifdef CONFIG_KEXEC_HANDOVER */ @@ -54,7 +63,7 @@ static inline void kho_radix_del_key(struct kho_radix_tree *tree, unsigned long key) { } static inline int kho_radix_walk_tree(struct kho_radix_tree *tree, - kho_radix_tree_walk_callback_t cb) + const struct kho_radix_walk_cb *cb) { return -EOPNOTSUPP; } diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c index afc986845839..b22b3cec251e 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -266,16 +266,18 @@ void kho_radix_del_key(struct kho_radix_tree *tree, unsigned long key) } EXPORT_SYMBOL_GPL(kho_radix_del_key); -static int kho_radix_walk_leaf(struct kho_radix_leaf *leaf, - unsigned long key, - kho_radix_tree_walk_callback_t cb) +static int kho_radix_walk_leaf(struct kho_radix_leaf *leaf, unsigned long key, + const struct kho_radix_walk_cb *cb) { unsigned long *bitmap = (unsigned long *)leaf; unsigned int i; int err; + if (!cb->key) + return 0; + for_each_set_bit(i, bitmap, PAGE_SIZE * BITS_PER_BYTE) { - err = cb(key | i); + err = cb->key(key | i); if (err) return err; } @@ -285,7 +287,7 @@ static int kho_radix_walk_leaf(struct kho_radix_leaf *leaf, static int __kho_radix_walk_tree(struct kho_radix_node *root, unsigned int level, unsigned long start, - kho_radix_tree_walk_callback_t cb) + const struct kho_radix_walk_cb *cb) { struct kho_radix_node *node; struct kho_radix_leaf *leaf; @@ -325,18 +327,16 @@ static int __kho_radix_walk_tree(struct kho_radix_node *root, /** * kho_radix_walk_tree - Traverses the radix tree and calls a callback for each key. * @tree: A pointer to the KHO radix tree to walk. - * @cb: A callback function of type kho_radix_tree_walk_callback_t that will be - * invoked for each key in the tree. + * @cb: Set of callbacks to be invoked during the tree walk. * - * This function walks the radix tree, searching from the specified top level - * down to the lowest level (level 0). For each key found, it invokes the - * provided callback. + * This function walks the radix tree, searching from the top level down to the + * lowest level (level 0), invoking the appropriate callbacks. * * Return: 0 if the walk completed the specified tree, or the non-zero return * value from the callback that stopped the walk. */ int kho_radix_walk_tree(struct kho_radix_tree *tree, - kho_radix_tree_walk_callback_t cb) + const struct kho_radix_walk_cb *cb) { if (WARN_ON_ONCE(!tree->root)) return -EINVAL; @@ -1396,10 +1396,13 @@ EXPORT_SYMBOL_GPL(kho_retrieve_subtree); static int __init kho_mem_retrieve(const void *fdt) { + const struct kho_radix_walk_cb cb = { + .key = kho_preserved_memory_reserve, + }; + kho_in.radix_tree.root = phys_to_virt(kho_get_mem_map_phys(fdt)); mutex_init(&kho_in.radix_tree.lock); - return kho_radix_walk_tree(&kho_in.radix_tree, - kho_preserved_memory_reserve); + return kho_radix_walk_tree(&kho_in.radix_tree, &cb); } static __init int kho_out_fdt_setup(void) -- 2.43.0