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 5BB96C5B552 for ; Fri, 30 May 2025 09:11:14 +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=ZEMUQQZUL2fjTR0/QHgYz5UYqcVXbfNX4AYnY/4uPmQ=; b=xUiePW1c5iO0/g0TNog2XEn6eo 1Pr7m1MCAn9CjQoF+StcyO5JBDJWj5kW7Ujeeqw/gVOt7oEFgXi7stVFc6FIggTNKwkdjzTb+coA1 M9VFdKoAuwvAyhJewRrti/hfzdPz0twtAy+m0aInUx6BkmWKvFcoIP2pJGmmwBRqT8s9rylkr195P 9EsIPFbl3kZrofsM6uNzQt5mUCH+liMJxmjSszTkZ6mnp0HrbAgi83knAOIxeNZdLYxhnf0jRUTUI hvQ0MCWRpWmZwjWoZfL9s9bVIr5oXsp2Tfo9fSHCZ2v71ROBj0rQXnX4ogBziK5svPtwR3WuHppul nzaTMZSw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uKvlc-000000005Fh-08Jc; Fri, 30 May 2025 09:11:08 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uKvfP-000000004NT-0uUV for linux-arm-kernel@lists.infradead.org; Fri, 30 May 2025 09:04:44 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3CDAC16F2; Fri, 30 May 2025 02:04:26 -0700 (PDT) Received: from MacBook-Pro.blr.arm.com (unknown [10.164.18.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9ED583F5A1; Fri, 30 May 2025 02:04:37 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org, david@redhat.com, catalin.marinas@arm.com, will@kernel.org Cc: lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, suzuki.poulose@arm.com, steven.price@arm.com, gshan@redhat.com, linux-arm-kernel@lists.infradead.org, Dev Jain Subject: [PATCH 2/3] arm64: pageattr: Use walk_page_range_novma() to change memory permissions Date: Fri, 30 May 2025 14:34:06 +0530 Message-Id: <20250530090407.19237-3-dev.jain@arm.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20250530090407.19237-1-dev.jain@arm.com> References: <20250530090407.19237-1-dev.jain@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250530_020443_344870_7E852DBB X-CRM114-Status: GOOD ( 13.99 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Move away from apply_to_page_range(), which does not honour leaf mappings, to walk_page_range_novma(). The callbacks emit a warning and return EINVAL if a partial range is detected. Signed-off-by: Dev Jain --- arch/arm64/mm/pageattr.c | 69 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 64 insertions(+), 5 deletions(-) diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 39fd1f7ff02a..a5c829c64969 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -20,6 +21,67 @@ struct page_change_data { pgprot_t clear_mask; }; +static pteval_t set_pageattr_masks(unsigned long val, struct mm_walk *walk) +{ + struct page_change_data *masks = walk->private; + unsigned long new_val = val; + + new_val &= ~(pgprot_val(masks->clear_mask)); + new_val |= (pgprot_val(masks->set_mask)); + + return new_val; +} + +static int pageattr_pud_entry(pud_t *pud, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pud_t val = pudp_get(pud); + + if (pud_leaf(val)) { + if (WARN_ON_ONCE((next - addr) != PUD_SIZE)) + return -EINVAL; + val = __pud(set_pageattr_masks(pud_val(val), walk)); + set_pud(pud, val); + walk->action = ACTION_CONTINUE; + } + + return 0; +} + +static int pageattr_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pmd_t val = pmdp_get(pmd); + + if (pmd_leaf(val)) { + if (WARN_ON_ONCE((next - addr) != PMD_SIZE)) + return -EINVAL; + val = __pmd(set_pageattr_masks(pmd_val(val), walk)); + set_pmd(pmd, val); + walk->action = ACTION_CONTINUE; + } + + return 0; +} + +static int pageattr_pte_entry(pte_t *pte, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pte_t val = ptep_get(pte); + + val = __pte(set_pageattr_masks(pte_val(val), walk)); + set_pte(pte, val); + + return 0; +} + +static const struct mm_walk_ops pageattr_ops = { + .pud_entry = pageattr_pud_entry, + .pmd_entry = pageattr_pmd_entry, + .pte_entry = pageattr_pte_entry, + .walk_lock = PGWALK_NOLOCK, +}; + bool rodata_full __ro_after_init = IS_ENABLED(CONFIG_RODATA_FULL_DEFAULT_ENABLED); bool can_set_direct_map(void) @@ -49,9 +111,6 @@ static int change_page_range(pte_t *ptep, unsigned long addr, void *data) return 0; } -/* - * This function assumes that the range is mapped with PAGE_SIZE pages. - */ static int __change_memory_common(unsigned long start, unsigned long size, pgprot_t set_mask, pgprot_t clear_mask) { @@ -61,8 +120,8 @@ static int __change_memory_common(unsigned long start, unsigned long size, data.set_mask = set_mask; data.clear_mask = clear_mask; - ret = apply_to_page_range(&init_mm, start, size, change_page_range, - &data); + ret = walk_page_range_novma(&init_mm, start, start + size, + &pageattr_ops, NULL, &data); /* * If the memory is being made valid without changing any other bits -- 2.30.2