From 5be05c35e72f7492105987e0231afab46b69935e Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 12 Oct 2023 09:40:43 +0200 Subject: s390/mm,fault: improve readability by using teid union Get rid of some magic numbers, and use the teid union and also some ptrace PSW defines to improve readability. Reviewed-by: Claudio Imbrenda Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/mm/fault.c | 49 +++++++++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 26 deletions(-) (limited to 'arch/s390/mm') diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 5466a30d1ec4..bcaac0f939df 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -36,6 +36,8 @@ #include #include #include +#include +#include #include #include #include @@ -43,8 +45,6 @@ #include #include "../kernel/entry.h" -#define __FAIL_ADDR_MASK -4096L - /* * Allocate private vm_fault_reason from top. * Please make sure it won't collide with vm_fault_reason. @@ -76,11 +76,9 @@ early_initcall(fault_init); */ static enum fault_type get_fault_type(struct pt_regs *regs) { - unsigned long trans_exc_code; + union teid teid = { .val = regs->int_parm_long }; - trans_exc_code = regs->int_parm_long & 3; - /* Primary address space */ - if (likely(trans_exc_code == 0)) { + if (likely(teid.as == PSW_BITS_AS_PRIMARY)) { if (user_mode(regs)) return USER_FAULT; if (!IS_ENABLED(CONFIG_PGSTE)) @@ -89,10 +87,10 @@ static enum fault_type get_fault_type(struct pt_regs *regs) return GMAP_FAULT; return KERNEL_FAULT; } - if (trans_exc_code == 2) + if (teid.as == PSW_BITS_AS_SECONDARY) return USER_FAULT; /* Access register mode, not used in the kernel */ - if (trans_exc_code == 1) + if (teid.as == PSW_BITS_AS_ACCREG) return USER_FAULT; /* Home space -> access via kernel ASCE */ return KERNEL_FAULT; @@ -100,17 +98,17 @@ static enum fault_type get_fault_type(struct pt_regs *regs) static unsigned long get_fault_address(struct pt_regs *regs) { - unsigned long trans_exc_code = regs->int_parm_long; + union teid teid = { .val = regs->int_parm_long }; - return trans_exc_code & __FAIL_ADDR_MASK; + return teid.addr * PAGE_SIZE; } static __always_inline bool fault_is_write(struct pt_regs *regs) { - unsigned long trans_exc_code = regs->int_parm_long; + union teid teid = { .val = regs->int_parm_long }; if (static_branch_likely(&have_store_indication)) - return (trans_exc_code & 0xc00) == 0x400; + return teid.fsi == TEID_FSI_STORE; return false; } @@ -176,22 +174,23 @@ bad: static void dump_fault_info(struct pt_regs *regs) { + union teid teid = { .val = regs->int_parm_long }; unsigned long asce; pr_alert("Failing address: %016lx TEID: %016lx\n", - get_fault_address(regs), regs->int_parm_long); + get_fault_address(regs), teid.val); pr_alert("Fault in "); - switch (regs->int_parm_long & 3) { - case 3: + switch (teid.as) { + case PSW_BITS_AS_HOME: pr_cont("home space "); break; - case 2: + case PSW_BITS_AS_SECONDARY: pr_cont("secondary space "); break; - case 1: + case PSW_BITS_AS_ACCREG: pr_cont("access register "); break; - case 0: + case PSW_BITS_AS_PRIMARY: pr_cont("primary space "); break; } @@ -497,11 +496,10 @@ out: void do_protection_exception(struct pt_regs *regs) { - unsigned long trans_exc_code; + union teid teid = { .val = regs->int_parm_long }; vm_fault_t fault; int access; - trans_exc_code = regs->int_parm_long; /* * Protection exceptions are suppressing, decrement psw address. * The exception to this rule are aborted transactions, for these @@ -514,13 +512,12 @@ void do_protection_exception(struct pt_regs *regs) * as a special case because the translation exception code * field is not guaranteed to contain valid data in this case. */ - if (unlikely(!(trans_exc_code & 4))) { + if (unlikely(!teid.b61)) { do_low_address(regs); return; } - if (unlikely(MACHINE_HAS_NX && (trans_exc_code & 0x80))) { - regs->int_parm_long = (trans_exc_code & ~PAGE_MASK) | - (regs->psw.addr & PAGE_MASK); + if (unlikely(MACHINE_HAS_NX && teid.b56)) { + regs->int_parm_long = (teid.addr * PAGE_SIZE) | (regs->psw.addr & PAGE_MASK); access = VM_EXEC; fault = VM_FAULT_BADACCESS; } else { @@ -548,6 +545,7 @@ NOKPROBE_SYMBOL(do_dat_exception); void do_secure_storage_access(struct pt_regs *regs) { + union teid teid = { .val = regs->int_parm_long }; unsigned long addr = get_fault_address(regs); struct vm_area_struct *vma; struct mm_struct *mm; @@ -561,8 +559,7 @@ void do_secure_storage_access(struct pt_regs *regs) * process. Bit 61 is not reliable without the misc UV feature, * therefore this needs to be checked too. */ - if (uv_has_feature(BIT_UV_FEAT_MISC) && - !test_bit_inv(61, ®s->int_parm_long)) { + if (uv_has_feature(BIT_UV_FEAT_MISC) && !teid.b61) { /* * When this happens, userspace did something that it * was not supposed to do, e.g. branching into secure -- cgit v1.2.3