projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 28080329 PM |
1 | /* |
| 2 | * TLB miss handler for SH with an MMU. | |
| 3 | * | |
| 4 | * Copyright (C) 1999 Niibe Yutaka | |
| 5 | * Copyright (C) 2003 - 2012 Paul Mundt | |
| 6 | * | |
| 7 | * This file is subject to the terms and conditions of the GNU General Public | |
| 8 | * License. See the file "COPYING" in the main directory of this archive | |
| 9 | * for more details. | |
| 10 | */ | |
| 11 | #include <linux/kernel.h> | |
| 12 | #include <linux/mm.h> | |
| 13 | #include <linux/kprobes.h> | |
| 14 | #include <linux/kdebug.h> | |
| 15 | #include <asm/mmu_context.h> | |
| 16 | #include <asm/thread_info.h> | |
| dcead6e5 | 17 | #include <asm/tlb.h> |
| 28080329 PM |
18 | |
| 19 | /* | |
| 20 | * Called with interrupts disabled. | |
| 21 | */ | |
| 22 | asmlinkage int __kprobes | |
| 23 | handle_tlbmiss(struct pt_regs *regs, unsigned long error_code, | |
| 24 | unsigned long address) | |
| 25 | { | |
| 26 | pgd_t *pgd; | |
| 874e2cc1 | 27 | p4d_t *p4d; |
| 28080329 PM |
28 | pud_t *pud; |
| 29 | pmd_t *pmd; | |
| 30 | pte_t *pte; | |
| 31 | pte_t entry; | |
| 32 | ||
| 33 | /* | |
| 34 | * We don't take page faults for P1, P2, and parts of P4, these | |
| 35 | * are always mapped, whether it be due to legacy behaviour in | |
| 36 | * 29-bit mode, or due to PMB configuration in 32-bit mode. | |
| 37 | */ | |
| 38 | if (address >= P3SEG && address < P3_ADDR_MAX) { | |
| 39 | pgd = pgd_offset_k(address); | |
| 40 | } else { | |
| 41 | if (unlikely(address >= TASK_SIZE || !current->mm)) | |
| 42 | return 1; | |
| 43 | ||
| 44 | pgd = pgd_offset(current->mm, address); | |
| 45 | } | |
| 46 | ||
| 874e2cc1 MR |
47 | p4d = p4d_offset(pgd, address); |
| 48 | if (p4d_none_or_clear_bad(p4d)) | |
| 49 | return 1; | |
| 50 | pud = pud_offset(p4d, address); | |
| 28080329 PM |
51 | if (pud_none_or_clear_bad(pud)) |
| 52 | return 1; | |
| 53 | pmd = pmd_offset(pud, address); | |
| 54 | if (pmd_none_or_clear_bad(pmd)) | |
| 55 | return 1; | |
| 56 | pte = pte_offset_kernel(pmd, address); | |
| 57 | entry = *pte; | |
| 58 | if (unlikely(pte_none(entry) || pte_not_present(entry))) | |
| 59 | return 1; | |
| 60 | if (unlikely(error_code && !pte_write(entry))) | |
| 61 | return 1; | |
| 62 | ||
| 63 | if (error_code) | |
| 64 | entry = pte_mkdirty(entry); | |
| 65 | entry = pte_mkyoung(entry); | |
| 66 | ||
| 67 | set_pte(pte, entry); | |
| 68 | ||
| 69 | #if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SMP) | |
| 70 | /* | |
| 71 | * SH-4 does not set MMUCR.RC to the corresponding TLB entry in | |
| 72 | * the case of an initial page write exception, so we need to | |
| 73 | * flush it in order to avoid potential TLB entry duplication. | |
| 74 | */ | |
| 75 | if (error_code == FAULT_CODE_INITIAL) | |
| 76 | local_flush_tlb_one(get_asid(), address & PAGE_MASK); | |
| 77 | #endif | |
| 78 | ||
| 79 | set_thread_fault_code(error_code); | |
| 80 | update_mmu_cache(NULL, address, pte); | |
| 81 | ||
| 82 | return 0; | |
| 83 | } |