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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C3AE9CAC5A9 for ; Thu, 18 Sep 2025 08:38:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A976A8E00D6; Thu, 18 Sep 2025 04:38:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9F2488E00D7; Thu, 18 Sep 2025 04:38:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 83C488E00D6; Thu, 18 Sep 2025 04:38:16 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 6CC448E0093 for ; Thu, 18 Sep 2025 04:38:16 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 355C71407EC for ; Thu, 18 Sep 2025 08:38:16 +0000 (UTC) X-FDA: 83901718992.15.681C35D Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) by imf14.hostedemail.com (Postfix) with ESMTP id DC88F100002 for ; Thu, 18 Sep 2025 08:38:13 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; spf=pass (imf14.hostedemail.com: domain of zhangchunyan@iscas.ac.cn designates 159.226.251.81 as permitted sender) smtp.mailfrom=zhangchunyan@iscas.ac.cn ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1758184694; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Oe3dGdnLdXHG/zv7BBC8zwyJe6cDbr6ySs0wYxHhjeI=; b=rGTEkqrfPVpX/keZLSaZ2ul7ZrOQ9xL2jk6/k30ltHiqSR7+U/w9qjfKv7F+H4utexMD7w Lro8Y3ZF4gj8sLWjWr2EAj1gqz9f15xGZowdfCaxJGj/XMEsQ5OWtYXwO2ijfAfPy7HeBk ZGwKfj/Sdo/KHGl5glYmbTQXeSdS3hM= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=none; spf=pass (imf14.hostedemail.com: domain of zhangchunyan@iscas.ac.cn designates 159.226.251.81 as permitted sender) smtp.mailfrom=zhangchunyan@iscas.ac.cn; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1758184694; a=rsa-sha256; cv=none; b=04I4wqY38JclQbSNKVQB/uzi9zCNj9yTxjopzQPTCq+4K3e0XkY8nq+KphUr1LLp31r3iH S/2diBCAZJbOvclC6L8nz5P6JNaAROSax9jVs+ehjHoFVkIzNKWKnAiDepYkh3Tq9Aczd5 WACWXoybBRv/65v0yfseumjzcuXRiEo= Received: from ubt.. (unknown [210.73.43.101]) by APP-03 (Coremail) with SMTP id rQCowACnu4XjxMtolHKCAw--.43062S7; Thu, 18 Sep 2025 16:38:03 +0800 (CST) From: Chunyan Zhang To: linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Deepak Gupta , Ved Shanbhogue , Alexander Viro , Christian Brauner , Jan Kara , Andrew Morton , Peter Xu , Arnd Bergmann , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Axel Rasmussen , Yuanchu Xie , Chunyan Zhang Subject: [PATCH V14 5/6] riscv: mm: Add userfaultfd write-protect support Date: Thu, 18 Sep 2025 16:37:30 +0800 Message-Id: <20250918083731.1820327-6-zhangchunyan@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250918083731.1820327-1-zhangchunyan@iscas.ac.cn> References: <20250918083731.1820327-1-zhangchunyan@iscas.ac.cn> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:rQCowACnu4XjxMtolHKCAw--.43062S7 X-Coremail-Antispam: 1UD129KBjvJXoWxZF48ZF4kKF4xKFW5urWrAFb_yoWruw15pr s5GayrurWDJF97tayftr4YgrWrZw4fWa4DWr9xCa1kJFy7K3yDXr95Kry3try8JFWvv347 WFWrKr1rCw47JFDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmFb7Iv0xC_Zr1lb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI 8067AKxVWUAVCq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28C jxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI 8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2 z280aVCY1x0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0V AKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Gr0_Cr1l Ox8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04 v7MxkF7I0En4kS14v26r4a6rW5MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j 6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7 AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1I6r4UMIIF0xvE 2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42 IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsGvfC2 KfnxnUUI43ZEXa7IUnq-e5UUUUU== X-Originating-IP: [210.73.43.101] X-CM-SenderInfo: x2kd0wxfkx051dq6x2xfdvhtffof0/1tbiDAgJB2jLv34ZIAAAsR X-Rspamd-Queue-Id: DC88F100002 X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: kwmoqxqzsofe9ssu9e4n4rp6as5cyg8q X-HE-Tag: 1758184693-792769 X-HE-Meta: U2FsdGVkX19xEZn2LwqpXQl74orDqGPyldPL+TeGfJirxG/qJpZTja3CbVfeWpnNsb53OP0ob1pIP35QDQOxu/zVqoIBh7glA7XnPLLmFV4o/GJzCSwe8a7OQ08223ol0pRkRokA51cLdQVi+XofmEz/LK1ZbdDHd4J+P/iHMYb8cIahzQ39M6xCoLc2S5fQ681pFzLSy8115Un9ZeXIj4tsZ/ep8f92J1BzCop9wn/lvv98zV+evVFt3gyh4c3gCv6wH45TJGN1LQCQuceXqO+0HygGceu2KxyZPxB9vPazpyob13tC8W0JStuZca+m9EMXAU9MJQ7Mjt3WwnLtkTXikmMwD054cxInLDEMa67CUJ5h4vBILSRYo8wQcvuCvXbCxLz0y4Y7k+AuuYhXL1gghhItHQ4xCnHkNszC7WXcc5VCI1yy4bO3iyPvv43b9/ngSMf9Eq6f/WL1C6qQKLyJZL1jJd1ZnYJ6wsbP2hPpIxV2mXy8MTPXRVLQnBzWpjYtvcjB5bMRci2MoYZau0KyECUY0ScGy4mudR6njvW0r20giVMsVSWi+TFXCRoqpYA9nG9HqZ3gEz07VACllYAsSHw2InbwaiB7Rs1EwSVeUIp1ZQQhZHK7xWpwjGOAZ99zYbqi8uZvlzIsuvPFuT8ZcMWf0ZUMm/i+cWl5YfJFyHx7WrgdCtlYI3BVVTx7bUQqR32R/Bl44VNI3h/QSB5Hj+OJvWugQQafkSsUZE+DA8oOVWx0oqUISEULf6krxyXSFIn4OB4xXqEd18WoY5Gox1jr5MyFnVihxle6SOOX6cy1RlgaJVIU2fvU+VTHLmYS9mZp4g5vIuXbHRdPUwzjZSBhqM6nnfwJTLB9urKvR843UONUwOd6fafvKLIsKyNIwb0vrKMLi5R23sbSzjYLeN8bai8UTWr8VE9h5y1cMVcJbZryzNk8ak1AmArQQfy9kV1nqpWkZ1Nr2Xc 0VwFON7a nqzfXXUW61J6gvs/w8qTmVkGHLqTz8YVag7X8zUexatPuuRdQripXPVeZbkrKWpJnYRPYq0RqULx4BSW1q+Zg6sZsiw0udblngMg85thIg6NmtcaY1AwvbUg3p9ADx6JEAse1JYoFBZXSq35ssJHRi3sAZ73lHhMkGR8PhyG0yXUC0lu34EHWH4RslmuPC1yFiGaGqwv7oFfjIfY= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: The Svrsw60t59b extension allows to free the PTE reserved bits 60 and 59 for software, this patch uses bit 60 for uffd-wp tracking Additionally for tracking the uffd-wp state as a PTE swap bit, we borrow bit 4 which is not involved into swap entry computation. Signed-off-by: Chunyan Zhang --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable-bits.h | 18 +++++++ arch/riscv/include/asm/pgtable.h | 68 +++++++++++++++++++++++++++ 3 files changed, 87 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 53b73e4bdf3f..f928768bb14a 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -147,6 +147,7 @@ config RISCV select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if 64BIT && MMU select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD + select HAVE_ARCH_USERFAULTFD_WP if 64BIT && MMU && USERFAULTFD && RISCV_ISA_SVRSW60T59B select HAVE_ARCH_VMAP_STACK if MMU && 64BIT select HAVE_ASM_MODVERSIONS select HAVE_CONTEXT_TRACKING_USER diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h index f3bac2bbc157..b422d9691e60 100644 --- a/arch/riscv/include/asm/pgtable-bits.h +++ b/arch/riscv/include/asm/pgtable-bits.h @@ -38,6 +38,24 @@ #define _PAGE_SWP_SOFT_DIRTY 0 #endif /* CONFIG_MEM_SOFT_DIRTY */ +#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP + +/* ext_svrsw60t59b: Bit(60) for uffd-wp tracking */ +#define _PAGE_UFFD_WP \ + ((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ? \ + (1UL << 60) : 0) +/* + * Bit 4 is not involved into swap entry computation, so we + * can borrow it for swap page uffd-wp tracking. + */ +#define _PAGE_SWP_UFFD_WP \ + ((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ? \ + _PAGE_USER : 0) +#else +#define _PAGE_UFFD_WP 0 +#define _PAGE_SWP_UFFD_WP 0 +#endif + #define _PAGE_TABLE _PAGE_PRESENT /* diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index d7fe0f78107b..71e84c114dc4 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -416,6 +416,41 @@ static inline pte_t pte_wrprotect(pte_t pte) return __pte(pte_val(pte) & ~(_PAGE_WRITE)); } +#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP +#define pgtable_supports_uffd_wp() \ + riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B) + +static inline bool pte_uffd_wp(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_UFFD_WP); +} + +static inline pte_t pte_mkuffd_wp(pte_t pte) +{ + return pte_wrprotect(__pte(pte_val(pte) | _PAGE_UFFD_WP)); +} + +static inline pte_t pte_clear_uffd_wp(pte_t pte) +{ + return __pte(pte_val(pte) & ~(_PAGE_UFFD_WP)); +} + +static inline bool pte_swp_uffd_wp(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_SWP_UFFD_WP); +} + +static inline pte_t pte_swp_mkuffd_wp(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SWP_UFFD_WP); +} + +static inline pte_t pte_swp_clear_uffd_wp(pte_t pte) +{ + return __pte(pte_val(pte) & ~(_PAGE_SWP_UFFD_WP)); +} +#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */ + /* static inline pte_t pte_mkread(pte_t pte) */ static inline pte_t pte_mkwrite_novma(pte_t pte) @@ -838,6 +873,38 @@ static inline pud_t pud_mkspecial(pud_t pud) } #endif +#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP +static inline bool pmd_uffd_wp(pmd_t pmd) +{ + return pte_uffd_wp(pmd_pte(pmd)); +} + +static inline pmd_t pmd_mkuffd_wp(pmd_t pmd) +{ + return pte_pmd(pte_mkuffd_wp(pmd_pte(pmd))); +} + +static inline pmd_t pmd_clear_uffd_wp(pmd_t pmd) +{ + return pte_pmd(pte_clear_uffd_wp(pmd_pte(pmd))); +} + +static inline bool pmd_swp_uffd_wp(pmd_t pmd) +{ + return pte_swp_uffd_wp(pmd_pte(pmd)); +} + +static inline pmd_t pmd_swp_mkuffd_wp(pmd_t pmd) +{ + return pte_pmd(pte_swp_mkuffd_wp(pmd_pte(pmd))); +} + +static inline pmd_t pmd_swp_clear_uffd_wp(pmd_t pmd) +{ + return pte_pmd(pte_swp_clear_uffd_wp(pmd_pte(pmd))); +} +#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */ + #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY static inline bool pmd_soft_dirty(pmd_t pmd) { @@ -1066,6 +1133,7 @@ static inline pud_t pud_modify(pud_t pud, pgprot_t newprot) * bit 0: _PAGE_PRESENT (zero) * bit 1 to 2: (zero) * bit 3: _PAGE_SWP_SOFT_DIRTY + * bit 4: _PAGE_SWP_UFFD_WP * bit 5: _PAGE_PROT_NONE (zero) * bit 6: exclusive marker * bits 7 to 11: swap type -- 2.34.1