From 6f52b16c5b29b89d92c0e7236f4655dc8491ad70 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 1 Nov 2017 15:08:43 +0100 Subject: License cleanup: add SPDX license identifier to uapi header files with no license Many user space API headers are missing licensing information, which makes it hard for compliance tools to determine the correct license. By default are files without license information under the default license of the kernel, which is GPLV2. Marking them GPLV2 would exclude them from being included in non GPLV2 code, which is obviously not intended. The user space API headers fall under the syscall exception which is in the kernels COPYING file: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". otherwise syscall usage would not be possible. Update the files which contain no license information with an SPDX license identifier. The chosen identifier is 'GPL-2.0 WITH Linux-syscall-note' which is the officially assigned identifier for the Linux syscall exception. SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/prctl.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux/prctl.h') diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index a8d0759a9e40..b640071421f7 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _LINUX_PRCTL_H #define _LINUX_PRCTL_H -- cgit v1.2.3 From 7582e22038a266444eb87bc07c372592ad647439 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Tue, 31 Oct 2017 15:51:08 +0000 Subject: arm64/sve: Backend logic for setting the vector length MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch implements the core logic for changing a task's vector length on request from userspace. This will be used by the ptrace and prctl frontends that are implemented in later patches. The SVE architecture permits, but does not require, implementations to support vector lengths that are not a power of two. To handle this, logic is added to check a requested vector length against a possibly sparse bitmap of available vector lengths at runtime, so that the best supported value can be chosen. Signed-off-by: Dave Martin Reviewed-by: Catalin Marinas Cc: Alex Bennée Signed-off-by: Will Deacon --- include/uapi/linux/prctl.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/uapi/linux/prctl.h') diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index a8d0759a9e40..1b64901ca6b3 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -197,4 +197,9 @@ struct prctl_mm_map { # define PR_CAP_AMBIENT_LOWER 3 # define PR_CAP_AMBIENT_CLEAR_ALL 4 +/* arm64 Scalable Vector Extension controls */ +# define PR_SVE_SET_VL_ONEXEC (1 << 18) /* defer effect until exec */ +# define PR_SVE_VL_LEN_MASK 0xffff +# define PR_SVE_VL_INHERIT (1 << 17) /* inherit across exec */ + #endif /* _LINUX_PRCTL_H */ -- cgit v1.2.3 From 2d2123bc7c7f843aa9db87720de159a049839862 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Tue, 31 Oct 2017 15:51:14 +0000 Subject: arm64/sve: Add prctl controls for userspace vector length management MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds two arm64-specific prctls, to permit userspace to control its vector length: * PR_SVE_SET_VL: set the thread's SVE vector length and vector length inheritance mode. * PR_SVE_GET_VL: get the same information. Although these prctls resemble instruction set features in the SVE architecture, they provide additional control: the vector length inheritance mode is Linux-specific and nothing to do with the architecture, and the architecture does not permit EL0 to set its own vector length directly. Both can be used in portable tools without requiring the use of SVE instructions. Signed-off-by: Dave Martin Reviewed-by: Catalin Marinas Cc: Alex Bennée [will: Fixed up prctl constants to avoid clash with PDEATHSIG] Signed-off-by: Will Deacon --- include/uapi/linux/prctl.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/uapi/linux/prctl.h') diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 1b64901ca6b3..f60db5db6e8e 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -198,7 +198,11 @@ struct prctl_mm_map { # define PR_CAP_AMBIENT_CLEAR_ALL 4 /* arm64 Scalable Vector Extension controls */ +/* Flag values must be kept in sync with ptrace NT_ARM_SVE interface */ +#define PR_SVE_SET_VL 50 /* set task vector length */ # define PR_SVE_SET_VL_ONEXEC (1 << 18) /* defer effect until exec */ +#define PR_SVE_GET_VL 51 /* get task vector length */ +/* Bits common to PR_SVE_SET_VL and PR_SVE_GET_VL */ # define PR_SVE_VL_LEN_MASK 0xffff # define PR_SVE_VL_INHERIT (1 << 17) /* inherit across exec */ -- cgit v1.2.3