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-rw-r--r--arch/sh/mm/fault.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 716ebf568af..fa5d7f0b9f1 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -17,6 +17,7 @@
#include <linux/kprobes.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
#include <asm/kgdb.h>
extern void die(const char *,struct pt_regs *,long);
@@ -224,3 +225,89 @@ do_sigbus:
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.
+ */
+ local_flush_tlb_one(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;
+}