From patchwork Thu Oct 21 18:07:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 12576051 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B09AC433EF for ; Thu, 21 Oct 2021 18:08:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11FE961B04 for ; Thu, 21 Oct 2021 18:08:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231707AbhJUSKz (ORCPT ); Thu, 21 Oct 2021 14:10:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:55750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229914AbhJUSKz (ORCPT ); Thu, 21 Oct 2021 14:10:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8A2D661AFF; Thu, 21 Oct 2021 18:08:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634839719; bh=M4LJkzBz7sw8s9MUE7elvhkWEMMnDxNEEYrR7uMHihQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kri2lEFUxnLSnwlB7C0A47oaxc2RMEl6OQltlE6cTKn2tTykYSppv6cYWPHbctS6W kO4qF8rwssuUtFVSG+A1RXbLlEXY/fuWgGlsp1jjqpIh7wwVOQXQudaz+3T20CMGDZ +42UtmPHft4OhAVPa4uU9HFUUiKhPOXCtyUjeJf6Ku3Mxr0wsxv8kfPGLrSxwl0PHu F4WgoRDakHgVnvmrO4Jazy48UYwGJPtH37HP5tc0JwQPw33QHt9qw367le/VhSGb7W mMVQTqjWr+lmqQLzCLRfsYHclcW2NKYA/IWtUbplhtrSWiWB/8Cfg+B+CmVapE1cRt JW3nHH3mxPREQ== From: Mark Brown To: Catalin Marinas , Will Deacon , Shuah Khan , Shuah Khan Cc: Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, Mark Brown Subject: [PATCH v4 13/33] arm64/sme: Implement vector length configuration prctl()s Date: Thu, 21 Oct 2021 19:07:02 +0100 Message-Id: <20211021180722.3699248-14-broonie@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211021180722.3699248-1-broonie@kernel.org> References: <20211021180722.3699248-1-broonie@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=5719; h=from:subject; bh=M4LJkzBz7sw8s9MUE7elvhkWEMMnDxNEEYrR7uMHihQ=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBhcaxIGtXrzUEzHO65sWU9GCTVjdgTRfCTuiGcyn69 4lSeHeGJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYXGsSAAKCRAk1otyXVSH0MyhCA CCU5bE8GFLQOXXDnx6Am8TPEiazLkA9n+xD/Y0CLLkImSAQ+7Hs0nresFRhOC+03ISI6QGAXQ9KD6t 74ziW25lMqn12aDyZ+Mfe33PNpmcB8JkefVzP/A8VrRwxa4bk9yJVNnQiKlkbw7tq7tIwgfvVS842w g+LSb3oRuzDqfUE/va3NzQSx8RRDjlTRKMZZXxSXsUJ98G1gmlCf3TtN5ccNARjxBVSXk7ZKGULW0x XMBb61spXGU53HyZ1A+4b6JIHEBHEBiNKmR7LoaaO/e87jEyVVdOZN76PG27lCSIlq6ca2YKq00Cve Cr0er4dTRTcLQ/G8ct58sG3d8hxyZw X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org As for SVE provide a prctl() interface which allows processes to configure their SME vector length. Signed-off-by: Mark Brown --- arch/arm64/include/asm/fpsimd.h | 13 +++++++++++ arch/arm64/include/asm/processor.h | 4 +++- arch/arm64/include/asm/thread_info.h | 1 + arch/arm64/kernel/fpsimd.c | 32 ++++++++++++++++++++++++++++ include/uapi/linux/prctl.h | 9 ++++++++ kernel/sys.c | 12 +++++++++++ 6 files changed, 70 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index a65779fe6d56..3550317cbb3d 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -278,6 +278,9 @@ static inline int sme_max_virtualisable_vl(void) return vec_max_virtualisable_vl(ARM64_VEC_SME); } +extern int sme_set_current_vl(unsigned long arg); +extern int sme_get_current_vl(void); + #else static inline void sme_setup(void) { } @@ -287,6 +290,16 @@ static inline int sme_max_virtualisable_vl(void) { return 0; } static inline void sme_smstart_sm(void) { } static inline void sme_smstop_sm(void) { } +static inline int sme_set_current_vl(unsigned long arg) +{ + return -EINVAL; +} + +static inline int sme_get_current_vl(void) +{ + return -EINVAL; +} + #endif /* ! CONFIG_ARM64_SME */ /* For use by EFI runtime services calls only */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 575a1fe719b7..a62d2f8045bf 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -354,9 +354,11 @@ extern void __init minsigstksz_setup(void); */ #include -/* Userspace interface for PR_SVE_{SET,GET}_VL prctl()s: */ +/* Userspace interface for PR_S[MV]E_{SET,GET}_VL prctl()s: */ #define SVE_SET_VL(arg) sve_set_current_vl(arg) #define SVE_GET_VL() sve_get_current_vl() +#define SME_SET_VL(arg) sme_set_current_vl(arg) +#define SME_GET_VL() sme_get_current_vl() /* PR_PAC_RESET_KEYS prctl */ #define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg) diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index d5c8ac81ce11..5c4355204f4a 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -81,6 +81,7 @@ int arch_dup_task_struct(struct task_struct *dst, #define TIF_SVE_VL_INHERIT 24 /* Inherit SVE vl_onexec across exec */ #define TIF_SSBD 25 /* Wants SSB mitigation */ #define TIF_TAGGED_ADDR 26 /* Allow tagged user addresses */ +#define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 65b6ccc3f8de..a31b47d78291 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -145,6 +145,8 @@ static unsigned int vec_vl_inherit_flag(enum vec_type type) switch (type) { case ARM64_VEC_SVE: return TIF_SVE_VL_INHERIT; + case ARM64_VEC_SME: + return TIF_SME_VL_INHERIT; default: WARN_ON_ONCE(1); return 0; @@ -797,6 +799,36 @@ int sve_get_current_vl(void) return vec_prctl_status(ARM64_VEC_SVE, 0); } +#ifdef CONFIG_ARM64_SME +/* PR_SME_SET_VL */ +int sme_set_current_vl(unsigned long arg) +{ + unsigned long vl, flags; + int ret; + + vl = arg & PR_SME_VL_LEN_MASK; + flags = arg & ~vl; + + if (!system_supports_sme() || is_compat_task()) + return -EINVAL; + + ret = vec_set_vector_length(current, ARM64_VEC_SME, vl, flags); + if (ret) + return ret; + + return vec_prctl_status(ARM64_VEC_SME, flags); +} + +/* PR_SME_GET_VL */ +int sme_get_current_vl(void) +{ + if (!system_supports_sme() || is_compat_task()) + return -EINVAL; + + return vec_prctl_status(ARM64_VEC_SME, 0); +} +#endif /* CONFIG_ARM64_SME */ + static void vec_probe_vqs(struct vl_info *info, DECLARE_BITMAP(map, SVE_VQ_MAX)) { diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 43bd7f713c39..b3212d73c198 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -269,4 +269,13 @@ struct prctl_mm_map { # define PR_SCHED_CORE_SHARE_FROM 3 /* pull core_sched cookie to pid */ # define PR_SCHED_CORE_MAX 4 +/* arm64 Scalable Matrix Extension controls */ +/* Flag values must be in sync with SVE versions */ +#define PR_SME_SET_VL 63 /* set task vector length */ +# define PR_SME_SET_VL_ONEXEC (1 << 18) /* defer effect until exec */ +#define PR_SME_GET_VL 64 /* get task vector length */ +/* Bits common to PR_SME_SET_VL and PR_SME_GET_VL */ +# define PR_SME_VL_LEN_MASK 0xffff +# define PR_SME_VL_INHERIT (1 << 17) /* inherit across exec */ + #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 8fdac0d90504..59b1ce29b6c9 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -116,6 +116,12 @@ #ifndef SVE_GET_VL # define SVE_GET_VL() (-EINVAL) #endif +#ifndef SME_SET_VL +# define SME_SET_VL(a) (-EINVAL) +#endif +#ifndef SME_GET_VL +# define SME_GET_VL() (-EINVAL) +#endif #ifndef PAC_RESET_KEYS # define PAC_RESET_KEYS(a, b) (-EINVAL) #endif @@ -2463,6 +2469,12 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, case PR_SVE_GET_VL: error = SVE_GET_VL(); break; + case PR_SME_SET_VL: + error = SME_SET_VL(arg2); + break; + case PR_SME_GET_VL: + error = SME_GET_VL(); + break; case PR_GET_SPECULATION_CTRL: if (arg3 || arg4 || arg5) return -EINVAL;