From nobody Tue Nov 26 17:34:04 2024 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 85C151DE4E4; Thu, 17 Oct 2024 13:15:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729170906; cv=none; b=BTkbc2B9z3M5uZHv7Exa3kZqV6lvWoDZQoAsXi7fYmNGM72GytKJsYp987SQEmLRNbLkvPMTk0lob3gvSAltiGVtg0vwF6NsOhDGm2ld0rbqpYn2ZDlSwK1AxF5TPB6RIFnpBqAW8xAQffLpuB03aRW2B7+9CpN4xLGtSYgAh3Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729170906; c=relaxed/simple; bh=IaVsmH+y6PdKPfrVHRIQwRr5lL7/jzUWONvh9P/JsWo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=esdwAgUBrdhBFRathU2Q1t6Zqd7tTXgbfoYrEmC5hlei4Jvrw3ux8JQ/fFZYdQOV1QPNgr4X4KKsQFBc1kIYdrflmrGy8x1BV8Ep86VIvZn00R/XpUD2xiCuA7X2WaMUAOG6pcjXYb4ecPbR5we9KC0tnQIe/YCPaGQ2bpNffTc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 8E9F7DA7; Thu, 17 Oct 2024 06:15:33 -0700 (PDT) Received: from e122027.cambridge.arm.com (e122027.cambridge.arm.com [10.1.35.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1FEB33F71E; Thu, 17 Oct 2024 06:14:59 -0700 (PDT) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Suzuki K Poulose , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Steven Price Subject: [PATCH v7 04/11] arm64: rsi: Add support for checking whether an MMIO is protected Date: Thu, 17 Oct 2024 14:14:27 +0100 Message-Id: <20241017131434.40935-5-steven.price@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241017131434.40935-1-steven.price@arm.com> References: <20241017131434.40935-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Suzuki K Poulose On Arm CCA, with RMM-v1.0, all MMIO regions are shared. However, in the future, an Arm CCA-v1.0 compliant guest may be run in a lesser privileged partition in the Realm World (with Arm CCA-v1.1 Planes feature). In this case, some of the MMIO regions may be emulated by a higher privileged component in the Realm world, i.e, protected. Thus the guest must decide today, whether a given MMIO region is shared vs Protected and create the stage1 mapping accordingly. On Arm CCA, this detection is based on the "IPA State" (RIPAS =3D=3D RIPAS_IO). Provide a helper to run this check on a given range of MMIO. Also, provide a arm64 helper which may be hooked in by other solutions. Reviewed-by: Catalin Marinas Reviewed-by: Gavin Shan Signed-off-by: Suzuki K Poulose Signed-off-by: Steven Price --- Changes since v6: * Renamed arm64_is_mmio_private() to arm64_is_protected_mmio(), and arm64_is_protected_mmio() to __arm64_is_protected_mmio() --- arch/arm64/include/asm/io.h | 8 ++++++++ arch/arm64/include/asm/rsi.h | 2 ++ arch/arm64/include/asm/rsi_cmds.h | 21 +++++++++++++++++++++ arch/arm64/kernel/rsi.c | 26 ++++++++++++++++++++++++++ 4 files changed, 57 insertions(+) diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index 1ada23a6ec19..8688343b71f2 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -17,6 +17,7 @@ #include #include #include +#include =20 /* * Generic IO read/write. These perform native-endian accesses. @@ -318,4 +319,11 @@ extern bool arch_memremap_can_ram_remap(resource_size_= t offset, size_t size, unsigned long flags); #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap =20 +static inline bool arm64_is_protected_mmio(phys_addr_t phys_addr, size_t s= ize) +{ + if (unlikely(is_realm_world())) + return __arm64_is_protected_mmio(phys_addr, size); + return false; +} + #endif /* __ASM_IO_H */ diff --git a/arch/arm64/include/asm/rsi.h b/arch/arm64/include/asm/rsi.h index acba065eb00e..188cbb9b23f5 100644 --- a/arch/arm64/include/asm/rsi.h +++ b/arch/arm64/include/asm/rsi.h @@ -14,6 +14,8 @@ DECLARE_STATIC_KEY_FALSE(rsi_present); =20 void __init arm64_rsi_init(void); =20 +bool __arm64_is_protected_mmio(phys_addr_t base, size_t size); + static inline bool is_realm_world(void) { return static_branch_unlikely(&rsi_present); diff --git a/arch/arm64/include/asm/rsi_cmds.h b/arch/arm64/include/asm/rsi= _cmds.h index 2fcf351b5634..e6a211001bd3 100644 --- a/arch/arm64/include/asm/rsi_cmds.h +++ b/arch/arm64/include/asm/rsi_cmds.h @@ -45,6 +45,27 @@ static inline unsigned long rsi_get_realm_config(struct = realm_config *cfg) return res.a0; } =20 +static inline unsigned long rsi_ipa_state_get(phys_addr_t start, + phys_addr_t end, + enum ripas *state, + phys_addr_t *top) +{ + struct arm_smccc_res res; + + arm_smccc_smc(SMC_RSI_IPA_STATE_GET, + start, end, 0, 0, 0, 0, 0, + &res); + + if (res.a0 =3D=3D RSI_SUCCESS) { + if (top) + *top =3D res.a1; + if (state) + *state =3D res.a2; + } + + return res.a0; +} + static inline long rsi_set_addr_range_state(phys_addr_t start, phys_addr_t end, enum ripas state, diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index cea8f0d39591..7e7934c4fca0 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -67,6 +67,32 @@ static void __init arm64_rsi_setup_memory(void) } } =20 +bool __arm64_is_protected_mmio(phys_addr_t base, size_t size) +{ + enum ripas ripas; + phys_addr_t end, top; + + /* Overflow ? */ + if (WARN_ON(base + size <=3D base)) + return false; + + end =3D ALIGN(base + size, RSI_GRANULE_SIZE); + base =3D ALIGN_DOWN(base, RSI_GRANULE_SIZE); + + while (base < end) { + if (WARN_ON(rsi_ipa_state_get(base, end, &ripas, &top))) + break; + if (WARN_ON(top <=3D base)) + break; + if (ripas !=3D RSI_RIPAS_DEV) + break; + base =3D top; + } + + return base >=3D end; +} +EXPORT_SYMBOL(__arm64_is_protected_mmio); + void __init arm64_rsi_init(void) { if (arm_smccc_1_1_get_conduit() !=3D SMCCC_CONDUIT_SMC) --=20 2.34.1