diff options
Diffstat (limited to 'arch/x86/mm/pat.c')
| -rw-r--r-- | arch/x86/mm/pat.c | 90 |
1 files changed, 61 insertions, 29 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 85cbd3cd3723..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", @@ -601,12 +628,13 @@ void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot) * Reserved non RAM regions only and after successful reserve_memtype, * this func also keeps identity mapping (if any) in sync with this new prot. */ -static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t vma_prot) +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); + unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK); is_ram = pagerange_is_ram(paddr, paddr + size); @@ -625,26 +653,27 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t vma_prot) return ret; if (flags != want_flags) { - free_memtype(paddr, paddr + size); - printk(KERN_ERR - "%s:%d map pfn expected mapping type %s for %Lx-%Lx, got %s\n", - current->comm, current->pid, - cattr_name(want_flags), - (unsigned long long)paddr, - (unsigned long long)(paddr + size), - cattr_name(flags)); - return -EINVAL; + if (strict_prot || !is_new_memtype_allowed(want_flags, flags)) { + free_memtype(paddr, paddr + size); + printk(KERN_ERR "%s:%d map pfn expected mapping type %s" + " for %Lx-%Lx, got %s\n", + current->comm, current->pid, + cattr_name(want_flags), + (unsigned long long)paddr, + (unsigned long long)(paddr + size), + cattr_name(flags)); + return -EINVAL; + } + /* + * We allow returning different type than the one requested in + * non strict case. + */ + *vma_prot = __pgprot((pgprot_val(*vma_prot) & + (~_PAGE_CACHE_MASK)) | + 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 " @@ -689,6 +718,7 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) unsigned long vma_start = vma->vm_start; unsigned long vma_end = vma->vm_end; unsigned long vma_size = vma_end - vma_start; + pgprot_t pgprot; if (!pat_enabled) return 0; @@ -702,7 +732,8 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) WARN_ON_ONCE(1); return -EINVAL; } - return reserve_pfn_range(paddr, vma_size, __pgprot(prot)); + pgprot = __pgprot(prot); + return reserve_pfn_range(paddr, vma_size, &pgprot, 1); } /* reserve entire vma page by page, using pfn and prot from pte */ @@ -710,7 +741,8 @@ int track_pfn_vma_copy(struct vm_area_struct *vma) if (follow_phys(vma, vma_start + i, 0, &prot, &paddr)) continue; - retval = reserve_pfn_range(paddr, PAGE_SIZE, __pgprot(prot)); + pgprot = __pgprot(prot); + retval = reserve_pfn_range(paddr, PAGE_SIZE, &pgprot, 1); if (retval) goto cleanup_ret; } @@ -741,7 +773,7 @@ cleanup_ret: * Note that this function can be called with caller trying to map only a * subrange/page inside the vma. */ -int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot, +int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot, unsigned long pfn, unsigned long size) { int retval = 0; @@ -758,14 +790,14 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot, if (is_linear_pfn_mapping(vma)) { /* reserve the whole chunk starting from vm_pgoff */ paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT; - return reserve_pfn_range(paddr, vma_size, prot); + return reserve_pfn_range(paddr, vma_size, prot, 0); } /* reserve page by page using pfn and size */ base_paddr = (resource_size_t)pfn << PAGE_SHIFT; for (i = 0; i < size; i += PAGE_SIZE) { paddr = base_paddr + i; - retval = reserve_pfn_range(paddr, PAGE_SIZE, prot); + retval = reserve_pfn_range(paddr, PAGE_SIZE, prot, 0); if (retval) goto cleanup_ret; } |