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author | Dave Martin <Dave.Martin@arm.com> | 2018-03-28 10:50:48 +0100 |
---|---|---|
committer | Will Deacon <will.deacon@arm.com> | 2018-03-28 15:20:17 +0100 |
commit | 20b8547277a6e8ee1d928792c1b2782c9a2a6cf5 (patch) | |
tree | b7a84cdb011209b33c8f8df19f6dfadadc429433 /arch/arm64/include/asm/fpsimd.h | |
parent | 7f170499f734c417290518aa50cac11953bf8161 (diff) | |
download | op-kernel-dev-20b8547277a6e8ee1d928792c1b2782c9a2a6cf5.zip op-kernel-dev-20b8547277a6e8ee1d928792c1b2782c9a2a6cf5.tar.gz |
arm64: fpsimd: Split cpu field out from struct fpsimd_state
In preparation for using a common representation of the FPSIMD
state for tasks and KVM vcpus, this patch separates out the "cpu"
field that is used to track the cpu on which the state was most
recently loaded.
This will allow common code to operate on task and vcpu contexts
without requiring the cpu field to be stored at the same offset
from the FPSIMD register data in both cases. This should avoid the
need for messing with the definition of those parts of struct
vcpu_arch that are exposed in the KVM user ABI.
The resulting change is also convenient for grouping and defining
the set of thread_struct fields that are supposed to be accessible
to copy_{to,from}_user(), which includes user_fpsimd_state but
should exclude the cpu field. This patch does not amend the
usercopy whitelist to match: that will be addressed in a subsequent
patch.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
[will: inline fpsimd_flush_state for now]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/fpsimd.h')
-rw-r--r-- | arch/arm64/include/asm/fpsimd.h | 29 |
1 files changed, 2 insertions, 27 deletions
diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index e345408..aa7162a 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -25,31 +25,6 @@ #include <linux/init.h> #include <linux/stddef.h> -/* - * FP/SIMD storage area has: - * - FPSR and FPCR - * - 32 128-bit data registers - * - * Note that user_fpsimd forms a prefix of this structure, which is - * relied upon in the ptrace FP/SIMD accessors. - */ -struct fpsimd_state { - union { - struct user_fpsimd_state user_fpsimd; - struct { - __uint128_t vregs[32]; - u32 fpsr; - u32 fpcr; - /* - * For ptrace compatibility, pad to next 128-bit - * boundary here if extending this struct. - */ - }; - }; - /* the id of the last cpu to have restored this state */ - unsigned int cpu; -}; - #if defined(__KERNEL__) && defined(CONFIG_COMPAT) /* Masks for extracting the FPSR and FPCR from the FPSCR */ #define VFP_FPSCR_STAT_MASK 0xf800009f @@ -63,8 +38,8 @@ struct fpsimd_state { struct task_struct; -extern void fpsimd_save_state(struct fpsimd_state *state); -extern void fpsimd_load_state(struct fpsimd_state *state); +extern void fpsimd_save_state(struct user_fpsimd_state *state); +extern void fpsimd_load_state(struct user_fpsimd_state *state); extern void fpsimd_thread_switch(struct task_struct *next); extern void fpsimd_flush_thread(void); |