diff options
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 36 | ||||
| -rw-r--r-- | arch/s390/mm/pageattr.c | 243 | ||||
| -rw-r--r-- | arch/s390/mm/vmem.c | 4 |
3 files changed, 250 insertions, 33 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 882d6f4aad25..9133388edd1f 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -34,6 +34,8 @@ extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096))); extern void paging_init(void); extern void vmem_map_init(void); +pmd_t *vmem_pmd_alloc(void); +pte_t *vmem_pte_alloc(void); /* * The S390 doesn't have any external MMU info: the kernel page @@ -477,6 +479,40 @@ static inline void csp(unsigned int *ptr, unsigned int old, unsigned int new) : "cc"); } +static inline void cspg(unsigned long *ptr, unsigned long old, unsigned long new) +{ + register unsigned long reg2 asm("2") = old; + register unsigned long reg3 asm("3") = new; + unsigned long address = (unsigned long)ptr | 1; + + asm volatile( + " .insn rre,0xb98a0000,%0,%3" + : "+d" (reg2), "+m" (*ptr) + : "d" (reg3), "d" (address) + : "cc"); +} + +#define CRDTE_DTT_PAGE 0x00UL +#define CRDTE_DTT_SEGMENT 0x10UL +#define CRDTE_DTT_REGION3 0x14UL +#define CRDTE_DTT_REGION2 0x18UL +#define CRDTE_DTT_REGION1 0x1cUL + +static inline void crdte(unsigned long old, unsigned long new, + unsigned long table, unsigned long dtt, + unsigned long address, unsigned long asce) +{ + register unsigned long reg2 asm("2") = old; + register unsigned long reg3 asm("3") = new; + register unsigned long reg4 asm("4") = table | dtt; + register unsigned long reg5 asm("5") = address; + + asm volatile(".insn rrf,0xb98f0000,%0,%2,%4,0" + : "+d" (reg2) + : "d" (reg3), "d" (reg4), "d" (reg5), "a" (asce) + : "memory", "cc"); +} + /* * pgd/pmd/pte query functions */ diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c index e67a8f712e19..91e5e29c1f5c 100644 --- a/arch/s390/mm/pageattr.c +++ b/arch/s390/mm/pageattr.c @@ -40,54 +40,235 @@ void __storage_key_init_range(unsigned long start, unsigned long end) } #endif -static pte_t *walk_page_table(unsigned long addr) +static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr, + unsigned long dtt) { - pgd_t *pgdp; - pud_t *pudp; + unsigned long table, mask; + + mask = 0; + if (MACHINE_HAS_EDAT2) { + switch (dtt) { + case CRDTE_DTT_REGION3: + mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1); + break; + case CRDTE_DTT_SEGMENT: + mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); + break; + case CRDTE_DTT_PAGE: + mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1); + break; + } + table = (unsigned long)old & mask; + crdte(*old, new, table, dtt, addr, S390_lowcore.kernel_asce); + } else if (MACHINE_HAS_IDTE) { + cspg(old, *old, new); + } else { + csp((unsigned int *)old + 1, *old, new); + } +} + +struct cpa { + unsigned int set_ro : 1; + unsigned int clear_ro : 1; +}; + +static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end, + struct cpa cpa) +{ + pte_t *ptep, new; + + ptep = pte_offset(pmdp, addr); + do { + if (pte_none(*ptep)) + return -EINVAL; + if (cpa.set_ro) + new = pte_wrprotect(*ptep); + else if (cpa.clear_ro) + new = pte_mkwrite(pte_mkdirty(*ptep)); + pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE); + ptep++; + addr += PAGE_SIZE; + cond_resched(); + } while (addr < end); + return 0; +} + +static int split_pmd_page(pmd_t *pmdp, unsigned long addr) +{ + unsigned long pte_addr, prot; + pte_t *pt_dir, *ptep; + pmd_t new; + int i, ro; + + pt_dir = vmem_pte_alloc(); + if (!pt_dir) + return -ENOMEM; + pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT; + ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT); + prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL); + ptep = pt_dir; + for (i = 0; i < PTRS_PER_PTE; i++) { + pte_val(*ptep) = pte_addr | prot; + pte_addr += PAGE_SIZE; + ptep++; + } + pmd_val(new) = __pa(pt_dir) | _SEGMENT_ENTRY; + pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT); + return 0; +} + +static void modify_pmd_page(pmd_t *pmdp, unsigned long addr, struct cpa cpa) +{ + pmd_t new; + + if (cpa.set_ro) + new = pmd_wrprotect(*pmdp); + else if (cpa.clear_ro) + new = pmd_mkwrite(pmd_mkdirty(*pmdp)); + pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT); +} + +static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end, + struct cpa cpa) +{ + unsigned long next; pmd_t *pmdp; - pte_t *ptep; + int rc = 0; - pgdp = pgd_offset_k(addr); - if (pgd_none(*pgdp)) - return NULL; - pudp = pud_offset(pgdp, addr); - if (pud_none(*pudp) || pud_large(*pudp)) - return NULL; pmdp = pmd_offset(pudp, addr); - if (pmd_none(*pmdp) || pmd_large(*pmdp)) - return NULL; - ptep = pte_offset_kernel(pmdp, addr); - if (pte_none(*ptep)) - return NULL; - return ptep; + do { + if (pmd_none(*pmdp)) + return -EINVAL; + next = pmd_addr_end(addr, end); + if (pmd_large(*pmdp)) { + if (addr & ~PMD_MASK || addr + PMD_SIZE > next) { + rc = split_pmd_page(pmdp, addr); + if (rc) + return rc; + continue; + } + modify_pmd_page(pmdp, addr, cpa); + } else { + rc = walk_pte_level(pmdp, addr, next, cpa); + if (rc) + return rc; + } + pmdp++; + addr = next; + cond_resched(); + } while (addr < end); + return rc; } -static void change_page_attr(unsigned long addr, int numpages, - pte_t (*set) (pte_t)) +static int split_pud_page(pud_t *pudp, unsigned long addr) { - pte_t *ptep; - int i; + unsigned long pmd_addr, prot; + pmd_t *pm_dir, *pmdp; + pud_t new; + int i, ro; - for (i = 0; i < numpages; i++) { - ptep = walk_page_table(addr); - if (WARN_ON_ONCE(!ptep)) - break; - *ptep = set(*ptep); - addr += PAGE_SIZE; + pm_dir = vmem_pmd_alloc(); + if (!pm_dir) + return -ENOMEM; + pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT; + ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT); + prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL); + pmdp = pm_dir; + for (i = 0; i < PTRS_PER_PMD; i++) { + pmd_val(*pmdp) = pmd_addr | prot; + pmd_addr += PMD_SIZE; + pmdp++; } - __tlb_flush_kernel(); + pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY; + pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3); + return 0; +} + +static void modify_pud_page(pud_t *pudp, unsigned long addr, struct cpa cpa) +{ + pud_t new; + + if (cpa.set_ro) + new = pud_wrprotect(*pudp); + else if (cpa.clear_ro) + new = pud_mkwrite(pud_mkdirty(*pudp)); + pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3); +} + +static int walk_pud_level(pgd_t *pgd, unsigned long addr, unsigned long end, + struct cpa cpa) +{ + unsigned long next; + pud_t *pudp; + int rc = 0; + + pudp = pud_offset(pgd, addr); + do { + if (pud_none(*pudp)) + return -EINVAL; + next = pud_addr_end(addr, end); + if (pud_large(*pudp)) { + if (addr & ~PUD_MASK || addr + PUD_SIZE > next) { + rc = split_pud_page(pudp, addr); + if (rc) + break; + continue; + } + modify_pud_page(pudp, addr, cpa); + } else { + rc = walk_pmd_level(pudp, addr, next, cpa); + } + pudp++; + addr = next; + cond_resched(); + } while (addr < end && !rc); + return rc; +} + +static DEFINE_MUTEX(cpa_mutex); + +static int change_page_attr(unsigned long addr, unsigned long end, + struct cpa cpa) +{ + unsigned long next; + int rc = -EINVAL; + pgd_t *pgdp; + + if (end >= MODULES_END) + return -EINVAL; + mutex_lock(&cpa_mutex); + pgdp = pgd_offset_k(addr); + do { + if (pgd_none(*pgdp)) + break; + next = pgd_addr_end(addr, end); + rc = walk_pud_level(pgdp, addr, next, cpa); + if (rc) + break; + cond_resched(); + } while (pgdp++, addr = next, addr < end && !rc); + mutex_unlock(&cpa_mutex); + return rc; } int set_memory_ro(unsigned long addr, int numpages) { - change_page_attr(addr, numpages, pte_wrprotect); - return 0; + struct cpa cpa = { + .set_ro = 1, + }; + + addr &= PAGE_MASK; + return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa); } int set_memory_rw(unsigned long addr, int numpages) { - change_page_attr(addr, numpages, pte_mkwrite); - return 0; + struct cpa cpa = { + .clear_ro = 1, + }; + + addr &= PAGE_MASK; + return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa); } /* not possible */ diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c index 4badd8252e3c..0a7b03496f67 100644 --- a/arch/s390/mm/vmem.c +++ b/arch/s390/mm/vmem.c @@ -47,7 +47,7 @@ static inline pud_t *vmem_pud_alloc(void) return pud; } -static inline pmd_t *vmem_pmd_alloc(void) +pmd_t *vmem_pmd_alloc(void) { pmd_t *pmd = NULL; @@ -58,7 +58,7 @@ static inline pmd_t *vmem_pmd_alloc(void) return pmd; } -static pte_t __ref *vmem_pte_alloc(void) +pte_t __ref *vmem_pte_alloc(void) { pte_t *pte; |