diff options
Diffstat (limited to 'arch/powerpc/mm/slb.c')
| -rw-r--r-- | arch/powerpc/mm/slb.c | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c index 637afb2386b..27922dff8b9 100644 --- a/arch/powerpc/mm/slb.c +++ b/arch/powerpc/mm/slb.c @@ -149,6 +149,35 @@ void slb_vmalloc_update(void) slb_flush_and_rebolt(); } +/* Helper function to compare esids. There are four cases to handle. + * 1. The system is not 1T segment size capable. Use the GET_ESID compare. + * 2. The system is 1T capable, both addresses are < 1T, use the GET_ESID compare. + * 3. The system is 1T capable, only one of the two addresses is > 1T. This is not a match. + * 4. The system is 1T capable, both addresses are > 1T, use the GET_ESID_1T macro to compare. + */ +static inline int esids_match(unsigned long addr1, unsigned long addr2) +{ + int esid_1t_count; + + /* System is not 1T segment size capable. */ + if (!cpu_has_feature(CPU_FTR_1T_SEGMENT)) + return (GET_ESID(addr1) == GET_ESID(addr2)); + + esid_1t_count = (((addr1 >> SID_SHIFT_1T) != 0) + + ((addr2 >> SID_SHIFT_1T) != 0)); + + /* both addresses are < 1T */ + if (esid_1t_count == 0) + return (GET_ESID(addr1) == GET_ESID(addr2)); + + /* One address < 1T, the other > 1T. Not a match */ + if (esid_1t_count == 1) + return 0; + + /* Both addresses are > 1T. */ + return (GET_ESID_1T(addr1) == GET_ESID_1T(addr2)); +} + /* Flush all user entries from the segment table of the current processor. */ void switch_slb(struct task_struct *tsk, struct mm_struct *mm) { @@ -194,15 +223,14 @@ void switch_slb(struct task_struct *tsk, struct mm_struct *mm) return; slb_allocate(pc); - if (GET_ESID(pc) == GET_ESID(stack)) + if (esids_match(pc,stack)) return; if (is_kernel_addr(stack)) return; slb_allocate(stack); - if ((GET_ESID(pc) == GET_ESID(unmapped_base)) - || (GET_ESID(stack) == GET_ESID(unmapped_base))) + if (esids_match(pc,unmapped_base) || esids_match(stack,unmapped_base)) return; if (is_kernel_addr(unmapped_base)) |