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-rw-r--r--arch/x86/include/asm/pgtable.h19
-rw-r--r--arch/x86/mm/pageattr.c10
-rw-r--r--arch/x86/mm/pat.c90
-rw-r--r--arch/x86/pci/i386.c12
-rw-r--r--include/asm-generic/pgtable.h4
-rw-r--r--mm/memory.c15
6 files changed, 100 insertions, 50 deletions
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 83e69f4..06bbcbd 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -341,6 +341,25 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
#define canon_pgprot(p) __pgprot(pgprot_val(p) & __supported_pte_mask)
+static inline int is_new_memtype_allowed(unsigned long flags,
+ unsigned long new_flags)
+{
+ /*
+ * Certain new memtypes are not allowed with certain
+ * requested memtype:
+ * - request is uncached, return cannot be write-back
+ * - request is write-combine, return cannot be write-back
+ */
+ if ((flags == _PAGE_CACHE_UC_MINUS &&
+ new_flags == _PAGE_CACHE_WB) ||
+ (flags == _PAGE_CACHE_WC &&
+ new_flags == _PAGE_CACHE_WB)) {
+ return 0;
+ }
+
+ return 1;
+}
+
#ifndef __ASSEMBLY__
/* Indicate that x86 has its own track and untrack pfn vma functions */
#define __HAVE_PFNMAP_TRACKING
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index e89d248..4cf30de 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -555,10 +555,12 @@ repeat:
if (!pte_val(old_pte)) {
if (!primary)
return 0;
- WARN(1, KERN_WARNING "CPA: called for zero pte. "
- "vaddr = %lx cpa->vaddr = %lx\n", address,
- *cpa->vaddr);
- return -EINVAL;
+
+ /*
+ * Special error value returned, indicating that the mapping
+ * did not exist at this address.
+ */
+ return -EFAULT;
}
if (level == PG_LEVEL_4K) {
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 85cbd3c..160c42d 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;
}
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index f884740..5ead808 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -314,17 +314,7 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
return retval;
if (flags != new_flags) {
- /*
- * Do not fallback to certain memory types with certain
- * requested type:
- * - request is uncached, return cannot be write-back
- * - request is uncached, return cannot be write-combine
- * - request is write-combine, return cannot be write-back
- */
- if ((flags == _PAGE_CACHE_UC_MINUS &&
- (new_flags == _PAGE_CACHE_WB)) ||
- (flags == _PAGE_CACHE_WC &&
- new_flags == _PAGE_CACHE_WB)) {
+ if (!is_new_memtype_allowed(flags, new_flags)) {
free_memtype(addr, addr+len);
return -EINVAL;
}
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 72ebe91..8e6d0ca 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -301,7 +301,7 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm,
* track_pfn_vma_new is called when a _new_ pfn mapping is being established
* for physical range indicated by pfn and size.
*/
-static inline int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot,
+static inline int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
unsigned long pfn, unsigned long size)
{
return 0;
@@ -332,7 +332,7 @@ static inline void untrack_pfn_vma(struct vm_area_struct *vma,
{
}
#else
-extern int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot,
+extern int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
unsigned long pfn, unsigned long size);
extern int track_pfn_vma_copy(struct vm_area_struct *vma);
extern void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
diff --git a/mm/memory.c b/mm/memory.c
index c2d4c47..22bfa7a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1511,6 +1511,7 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn)
{
int ret;
+ pgprot_t pgprot = vma->vm_page_prot;
/*
* Technically, architectures with pte_special can avoid all these
* restrictions (same for remap_pfn_range). However we would like
@@ -1525,10 +1526,10 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
if (addr < vma->vm_start || addr >= vma->vm_end)
return -EFAULT;
- if (track_pfn_vma_new(vma, vma->vm_page_prot, pfn, PAGE_SIZE))
+ if (track_pfn_vma_new(vma, &pgprot, pfn, PAGE_SIZE))
return -EINVAL;
- ret = insert_pfn(vma, addr, pfn, vma->vm_page_prot);
+ ret = insert_pfn(vma, addr, pfn, pgprot);
if (ret)
untrack_pfn_vma(vma, pfn, PAGE_SIZE);
@@ -1671,9 +1672,15 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
- err = track_pfn_vma_new(vma, prot, pfn, PAGE_ALIGN(size));
- if (err)
+ err = track_pfn_vma_new(vma, &prot, pfn, PAGE_ALIGN(size));
+ if (err) {
+ /*
+ * To indicate that track_pfn related cleanup is not
+ * needed from higher level routine calling unmap_vmas
+ */
+ vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
return -EINVAL;
+ }
BUG_ON(addr >= end);
pfn -= addr >> PAGE_SHIFT;
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