diff options
Diffstat (limited to 'arch/powerpc/mm/book3s64/hash_utils.c')
| -rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 101 |
1 files changed, 69 insertions, 32 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 73b06adb6eeb..581b20a2feaf 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -38,6 +38,7 @@ #include <linux/pgtable.h> #include <asm/debugfs.h> +#include <asm/interrupt.h> #include <asm/processor.h> #include <asm/mmu.h> #include <asm/mmu_context.h> @@ -1143,10 +1144,10 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) page = pte_page(pte); /* page is dirty */ - if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) { + if (!test_bit(PG_dcache_clean, &page->flags) && !PageReserved(page)) { if (trap == 0x400) { flush_dcache_icache_page(page); - set_bit(PG_arch_1, &page->flags); + set_bit(PG_dcache_clean, &page->flags); } else pp |= HPTE_R_N; } @@ -1288,7 +1289,6 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, unsigned long flags) { bool is_thp; - enum ctx_state prev_state = exception_enter(); pgd_t *pgdir; unsigned long vsid; pte_t *ptep; @@ -1490,7 +1490,6 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, DBG_LOW(" -> rc=%d\n", rc); bail: - exception_exit(prev_state); return rc; } EXPORT_SYMBOL_GPL(hash_page_mm); @@ -1512,16 +1511,22 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap, } EXPORT_SYMBOL_GPL(hash_page); -int __hash_page(unsigned long trap, unsigned long ea, unsigned long dsisr, - unsigned long msr) +DECLARE_INTERRUPT_HANDLER_RET(__do_hash_fault); +DEFINE_INTERRUPT_HANDLER_RET(__do_hash_fault) { + unsigned long ea = regs->dar; + unsigned long dsisr = regs->dsisr; unsigned long access = _PAGE_PRESENT | _PAGE_READ; unsigned long flags = 0; - struct mm_struct *mm = current->mm; - unsigned int region_id = get_region_id(ea); + struct mm_struct *mm; + unsigned int region_id; + long err; + region_id = get_region_id(ea); if ((region_id == VMALLOC_REGION_ID) || (region_id == IO_REGION_ID)) mm = &init_mm; + else + mm = current->mm; if (dsisr & DSISR_NOHPTE) flags |= HPTE_NOHPTE_UPDATE; @@ -1537,13 +1542,66 @@ int __hash_page(unsigned long trap, unsigned long ea, unsigned long dsisr, * 2) user space access kernel space. */ access |= _PAGE_PRIVILEGED; - if ((msr & MSR_PR) || (region_id == USER_REGION_ID)) + if (user_mode(regs) || (region_id == USER_REGION_ID)) access &= ~_PAGE_PRIVILEGED; - if (trap == 0x400) + if (regs->trap == 0x400) access |= _PAGE_EXEC; - return hash_page_mm(mm, ea, access, trap, flags); + err = hash_page_mm(mm, ea, access, regs->trap, flags); + if (unlikely(err < 0)) { + // failed to instert a hash PTE due to an hypervisor error + if (user_mode(regs)) { + if (IS_ENABLED(CONFIG_PPC_SUBPAGE_PROT) && err == -2) + _exception(SIGSEGV, regs, SEGV_ACCERR, ea); + else + _exception(SIGBUS, regs, BUS_ADRERR, ea); + } else { + bad_page_fault(regs, SIGBUS); + } + err = 0; + } + + return err; +} + +/* + * The _RAW interrupt entry checks for the in_nmi() case before + * running the full handler. + */ +DEFINE_INTERRUPT_HANDLER_RAW(do_hash_fault) +{ + unsigned long dsisr = regs->dsisr; + long err; + + if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_KEYFAULT))) + goto page_fault; + + /* + * If we are in an "NMI" (e.g., an interrupt when soft-disabled), then + * don't call hash_page, just fail the fault. This is required to + * prevent re-entrancy problems in the hash code, namely perf + * interrupts hitting while something holds H_PAGE_BUSY, and taking a + * hash fault. See the comment in hash_preload(). + * + * We come here as a result of a DSI at a point where we don't want + * to call hash_page, such as when we are accessing memory (possibly + * user memory) inside a PMU interrupt that occurred while interrupts + * were soft-disabled. We want to invoke the exception handler for + * the access, or panic if there isn't a handler. + */ + if (unlikely(in_nmi())) { + do_bad_page_fault_segv(regs); + return 0; + } + + err = __do_hash_fault(regs); + if (err) { +page_fault: + err = hash__do_page_fault(regs); + } + + return err; } #ifdef CONFIG_PPC_MM_SLICES @@ -1843,27 +1901,6 @@ void flush_hash_range(unsigned long number, int local) } } -/* - * low_hash_fault is called when we the low level hash code failed - * to instert a PTE due to an hypervisor error - */ -void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc) -{ - enum ctx_state prev_state = exception_enter(); - - if (user_mode(regs)) { -#ifdef CONFIG_PPC_SUBPAGE_PROT - if (rc == -2) - _exception(SIGSEGV, regs, SEGV_ACCERR, address); - else -#endif - _exception(SIGBUS, regs, BUS_ADRERR, address); - } else - bad_page_fault(regs, address, SIGBUS); - - exception_exit(prev_state); -} - long hpte_insert_repeating(unsigned long hash, unsigned long vpn, unsigned long pa, unsigned long rflags, unsigned long vflags, int psize, int ssize) |