xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

arm64: fpsimd: Split cpu field out from struct fpsimd_state

Browse Source 
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>
This commit is contained in:
Dave Martin
2018-03-28 10:50:48 +01:00
committed by Will Deacon
parent 7f170499f7
commit 20b8547277
6 changed files with 29 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
arch/arm64/kernel/ptrace.c
View File

@@ -629,7 +629,7 @@ static int __fpr_get(struct task_struct *target,
sve_sync_to_fpsimd(target);
uregs = &target->thread.fpsimd_state.user_fpsimd;
uregs = &target->thread.fpsimd_state;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs,
start_pos, start_pos + sizeof(*uregs));
@@ -660,14 +660,14 @@ static int __fpr_set(struct task_struct *target,
*/
sve_sync_to_fpsimd(target);
newstate = target->thread.fpsimd_state.user_fpsimd;
newstate = target->thread.fpsimd_state;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate,
start_pos, start_pos + sizeof(newstate));
if (ret)
return ret;
target->thread.fpsimd_state.user_fpsimd = newstate;
target->thread.fpsimd_state = newstate;
return ret;
}
@@ -1169,7 +1169,7 @@ static int compat_vfp_get(struct task_struct *target,
compat_ulong_t fpscr;
int ret, vregs_end_pos;
uregs = &target->thread.fpsimd_state.user_fpsimd;
uregs = &target->thread.fpsimd_state;
if (target == current)
fpsimd_preserve_current_state();
@@ -1202,7 +1202,7 @@ static int compat_vfp_set(struct task_struct *target,
compat_ulong_t fpscr;
int ret, vregs_end_pos;
uregs = &target->thread.fpsimd_state.user_fpsimd;
uregs = &target->thread.fpsimd_state;
vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,