diff options
Diffstat (limited to 'arch/x86/mm/pat.c')
| -rw-r--r-- | arch/x86/mm/pat.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 8b08fb955274..160c42d3eb8f 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -505,6 +505,35 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size) } #endif /* CONFIG_STRICT_DEVMEM */ +/* + * Change the memory type for the physial address range in kernel identity + * mapping space if that range is a part of identity map. + */ +static int kernel_map_sync_memtype(u64 base, unsigned long size, + unsigned long flags) +{ + unsigned long id_sz; + int ret; + + if (!pat_enabled || base >= __pa(high_memory)) + return 0; + + id_sz = (__pa(high_memory) < base + size) ? + __pa(high_memory) - base : + size; + + ret = ioremap_change_attr((unsigned long)__va(base), id_sz, flags); + /* + * -EFAULT return means that the addr was not valid and did not have + * any identity mapping. That case is a success for + * kernel_map_sync_memtype. + */ + if (ret == -EFAULT) + ret = 0; + + return ret; +} + int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, unsigned long size, pgprot_t *vma_prot) { @@ -555,9 +584,7 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, if (retval < 0) return 0; - if (((pfn < max_low_pfn_mapped) || - (pfn >= (1UL<<(32 - PAGE_SHIFT)) && pfn < max_pfn_mapped)) && - ioremap_change_attr((unsigned long)__va(offset), size, flags) < 0) { + if (kernel_map_sync_memtype(offset, size, flags)) { free_memtype(offset, offset + size); printk(KERN_INFO "%s:%d /dev/mem ioremap_change_attr failed %s for %Lx-%Lx\n", @@ -605,7 +632,7 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot, int strict_prot) { int is_ram = 0; - int id_sz, ret; + int ret; unsigned long flags; unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK); @@ -646,15 +673,7 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot, flags); } - /* Need to keep identity mapping in sync */ - if (paddr >= __pa(high_memory)) - return 0; - - id_sz = (__pa(high_memory) < paddr + size) ? - __pa(high_memory) - paddr : - size; - - if (ioremap_change_attr((unsigned long)__va(paddr), id_sz, flags) < 0) { + if (kernel_map_sync_memtype(paddr, size, flags)) { free_memtype(paddr, paddr + size); printk(KERN_ERR "%s:%d reserve_pfn_range ioremap_change_attr failed %s " |