sh: TLB miss fast-path optimizations.
Handle simple TLB miss faults which can be resolved completely
from the page table in assembler.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 88e9663..6cd6d00 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -20,6 +20,7 @@
bool
select CPU_HAS_INTEVT
select CPU_HAS_SR_RB
+ select CPU_HAS_PTEA if !CPU_SUBTYPE_ST40
config CPU_SH4A
bool
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 128907e..123fb80 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -223,89 +223,3 @@
if (!user_mode(regs))
goto no_context;
}
-
-#ifdef CONFIG_SH_STORE_QUEUES
-/*
- * This is a special case for the SH-4 store queues, as pages for this
- * space still need to be faulted in before it's possible to flush the
- * store queue cache for writeout to the remapped region.
- */
-#define P3_ADDR_MAX (P4SEG_STORE_QUE + 0x04000000)
-#else
-#define P3_ADDR_MAX P4SEG
-#endif
-
-/*
- * Called with interrupts disabled.
- */
-asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs,
- unsigned long writeaccess,
- unsigned long address)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- pte_t entry;
- struct mm_struct *mm = current->mm;
- spinlock_t *ptl;
- int ret = 1;
-
-#ifdef CONFIG_SH_KGDB
- if (kgdb_nofault && kgdb_bus_err_hook)
- kgdb_bus_err_hook();
-#endif
-
- /*
- * We don't take page faults for P1, P2, and parts of P4, these
- * are always mapped, whether it be due to legacy behaviour in
- * 29-bit mode, or due to PMB configuration in 32-bit mode.
- */
- if (address >= P3SEG && address < P3_ADDR_MAX) {
- pgd = pgd_offset_k(address);
- mm = NULL;
- } else {
- if (unlikely(address >= TASK_SIZE || !mm))
- return 1;
-
- pgd = pgd_offset(mm, address);
- }
-
- pud = pud_offset(pgd, address);
- if (pud_none_or_clear_bad(pud))
- return 1;
- pmd = pmd_offset(pud, address);
- if (pmd_none_or_clear_bad(pmd))
- return 1;
-
- if (mm)
- pte = pte_offset_map_lock(mm, pmd, address, &ptl);
- else
- pte = pte_offset_kernel(pmd, address);
-
- entry = *pte;
- if (unlikely(pte_none(entry) || pte_not_present(entry)))
- goto unlock;
- if (unlikely(writeaccess && !pte_write(entry)))
- goto unlock;
-
- if (writeaccess)
- entry = pte_mkdirty(entry);
- entry = pte_mkyoung(entry);
-
-#ifdef CONFIG_CPU_SH4
- /*
- * ITLB is not affected by "ldtlb" instruction.
- * So, we need to flush the entry by ourselves.
- */
- __flush_tlb_page(get_asid(), address & PAGE_MASK);
-#endif
-
- set_pte(pte, entry);
- update_mmu_cache(NULL, address, entry);
- ret = 0;
-unlock:
- if (mm)
- pte_unmap_unlock(pte, ptl);
- return ret;
-}