[PATCH v3 09/11] s390/mm: Simplify get_fault_type()

From: Claudio Imbrenda
Date: Tue Oct 15 2024 - 12:45:47 EST


From: Heiko Carstens <hca@xxxxxxxxxxxxx>

With the gmap code gone get_fault_type() can be simplified:

- every fault with user_mode(regs) == true must be a fault in user address
space

- every fault with user_mode(regs) == false is only a fault in user
address space if the used address space is the secondary address space

- every other fault is within the kernel address space

Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Reviewed-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
---
arch/s390/mm/fault.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index e48910b0b816..6e96fc7905fc 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -68,17 +68,10 @@ static enum fault_type get_fault_type(struct pt_regs *regs)
{
union teid teid = { .val = regs->int_parm_long };

- if (likely(teid.as == PSW_BITS_AS_PRIMARY)) {
- if (user_mode(regs))
- return USER_FAULT;
- return KERNEL_FAULT;
- }
- if (teid.as == PSW_BITS_AS_SECONDARY)
+ if (user_mode(regs))
return USER_FAULT;
- /* Access register mode, not used in the kernel */
- if (teid.as == PSW_BITS_AS_ACCREG)
+ if (teid.as == PSW_BITS_AS_SECONDARY)
return USER_FAULT;
- /* Home space -> access via kernel ASCE */
return KERNEL_FAULT;
}

--
2.47.0