x86: Use new cache mode type in memtype related functions

Instead of directly using the cache mode bits in the pte switch to
using the cache mode type.

Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stefan.bader@canonical.com
Cc: xen-devel@lists.xensource.com
Cc: konrad.wilk@oracle.com
Cc: ville.syrjala@linux.intel.com
Cc: david.vrabel@citrix.com
Cc: jbeulich@suse.com
Cc: toshi.kani@hp.com
Cc: plagnioj@jcrosoft.com
Cc: tomi.valkeinen@ti.com
Cc: bhelgaas@google.com
Link: http://lkml.kernel.org/r/1415019724-4317-14-git-send-email-jgross@suse.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

7 files changed, 96 insertions, 90 deletions

diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h
index 9863ee3747da..157644bdf70e 100644
--- a/arch/x86/include/asm/cacheflush.h
+++ b/arch/x86/include/asm/cacheflush.h
@@ -9,10 +9,10 @@
 /*
  * X86 PAT uses page flags WC and Uncached together to keep track of
  * memory type of pages that have backing page struct. X86 PAT supports 3
- * different memory types, _PAGE_CACHE_WB, _PAGE_CACHE_WC and
- * _PAGE_CACHE_UC_MINUS and fourth state where page's memory type has not
+ * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
+ * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
  * been changed from its default (value of -1 used to denote this).
- * Note we do not support _PAGE_CACHE_UC here.
+ * Note we do not support _PAGE_CACHE_MODE_UC here.
  */
 
 #define _PGMT_DEFAULT           0
@@ -22,36 +22,40 @@
 #define _PGMT_MASK              (1UL << PG_uncached | 1UL << PG_arch_1)
 #define _PGMT_CLEAR_MASK        (~_PGMT_MASK)
 
-static inline unsigned long get_page_memtype(struct page *pg)
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
 {
         unsigned long pg_flags = pg->flags & _PGMT_MASK;
 
         if (pg_flags == _PGMT_DEFAULT)
                 return -1;
         else if (pg_flags == _PGMT_WC)
-                return _PAGE_CACHE_WC;
+                return _PAGE_CACHE_MODE_WC;
         else if (pg_flags == _PGMT_UC_MINUS)
-                return _PAGE_CACHE_UC_MINUS;
+                return _PAGE_CACHE_MODE_UC_MINUS;
         else
-                return _PAGE_CACHE_WB;
+                return _PAGE_CACHE_MODE_WB;
 }
 
-static inline void set_page_memtype(struct page *pg, unsigned long memtype)
+static inline void set_page_memtype(struct page *pg,
+                                    enum page_cache_mode memtype)
 {
-        unsigned long memtype_flags = _PGMT_DEFAULT;
+        unsigned long memtype_flags;
         unsigned long old_flags;
         unsigned long new_flags;
 
         switch (memtype) {
-        case _PAGE_CACHE_WC:
+        case _PAGE_CACHE_MODE_WC:
                 memtype_flags = _PGMT_WC;
                 break;
-        case _PAGE_CACHE_UC_MINUS:
+        case _PAGE_CACHE_MODE_UC_MINUS:
                 memtype_flags = _PGMT_UC_MINUS;
                 break;
-        case _PAGE_CACHE_WB:
+        case _PAGE_CACHE_MODE_WB:
                 memtype_flags = _PGMT_WB;
                 break;
+        default:
+                memtype_flags = _PGMT_DEFAULT;
+                break;
         }
 
         do {
@@ -60,8 +64,14 @@ static inline void set_page_memtype(struct page *pg, unsigned long memtype)
         } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
 }
 #else
-static inline unsigned long get_page_memtype(struct page *pg) { return -1; }
-static inline void set_page_memtype(struct page *pg, unsigned long memtype) { }
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
+{
+        return -1;
+}
+static inline void set_page_memtype(struct page *pg,
+                                    enum page_cache_mode memtype)
+{
+}
 #endif
 
 /*
diff --git a/arch/x86/include/asm/pat.h b/arch/x86/include/asm/pat.h
index d35ee2d976ca..150407a7234d 100644
--- a/arch/x86/include/asm/pat.h
+++ b/arch/x86/include/asm/pat.h
@@ -13,7 +13,7 @@ static const int pat_enabled;
 extern void pat_init(void);
 
 extern int reserve_memtype(u64 start, u64 end,
-                unsigned long req_type, unsigned long *ret_type);
+                enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm);
 extern int free_memtype(u64 start, u64 end);
 
 extern int kernel_map_sync_memtype(u64 base, unsigned long size,
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index f31507f6f60b..8832e510941e 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -83,7 +83,6 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
         const unsigned long unaligned_size = size;
         struct vm_struct *area;
         enum page_cache_mode new_pcm;
-        unsigned long new_prot_val;
         pgprot_t prot;
         int retval;
         void __iomem *ret_addr;
@@ -135,14 +134,12 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
         size = PAGE_ALIGN(last_addr+1) - phys_addr;
 
         retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
-                                 cachemode2protval(pcm), &new_prot_val);
+                                                pcm, &new_pcm);
         if (retval) {
                 printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
                 return NULL;
         }
 
-        new_pcm = pgprot2cachemode(__pgprot(new_prot_val));
-
         if (pcm != new_pcm) {
                 if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) {
                         printk(KERN_ERR
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 9f7e1b445e66..de807c9daad1 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -1451,7 +1451,7 @@ int set_memory_uc(unsigned long addr, int numpages)
          * for now UC MINUS. see comments in ioremap_nocache()
          */
         ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
-                            _PAGE_CACHE_UC_MINUS, NULL);
+                              _PAGE_CACHE_MODE_UC_MINUS, NULL);
         if (ret)
                 goto out_err;
 
@@ -1479,7 +1479,7 @@ static int _set_memory_array(unsigned long *addr, int addrinarray,
          */
         for (i = 0; i < addrinarray; i++) {
                 ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE,
-                                        cachemode2protval(new_type), NULL);
+                                        new_type, NULL);
                 if (ret)
                         goto out_free;
         }
@@ -1544,7 +1544,7 @@ int set_memory_wc(unsigned long addr, int numpages)
                 return set_memory_uc(addr, numpages);
 
         ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
-                _PAGE_CACHE_WC, NULL);
+                _PAGE_CACHE_MODE_WC, NULL);
         if (ret)
                 goto out_err;
 
@@ -1662,8 +1662,7 @@ static int _set_pages_array(struct page **pages, int addrinarray,
                         continue;
                 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
                 end = start + PAGE_SIZE;
-                if (reserve_memtype(start, end, cachemode2protval(new_type),
-                                    NULL))
+                if (reserve_memtype(start, end, new_type, NULL))
                         goto err_out;
         }
 
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 8f68a83491ba..ef75f3f89810 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -139,20 +139,21 @@ static DEFINE_SPINLOCK(memtype_lock);	/* protects memtype accesses */
  * The intersection is based on "Effective Memory Type" tables in IA-32
  * SDM vol 3a
  */
-static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
+static unsigned long pat_x_mtrr_type(u64 start, u64 end,
+                                     enum page_cache_mode req_type)
 {
         /*
          * Look for MTRR hint to get the effective type in case where PAT
          * request is for WB.
          */
-        if (req_type == _PAGE_CACHE_WB) {
+        if (req_type == _PAGE_CACHE_MODE_WB) {
                 u8 mtrr_type;
 
                 mtrr_type = mtrr_type_lookup(start, end);
                 if (mtrr_type != MTRR_TYPE_WRBACK)
-                        return _PAGE_CACHE_UC_MINUS;
+                        return _PAGE_CACHE_MODE_UC_MINUS;
 
-                return _PAGE_CACHE_WB;
+                return _PAGE_CACHE_MODE_WB;
         }
 
         return req_type;
@@ -207,25 +208,26 @@ static int pat_pagerange_is_ram(resource_size_t start, resource_size_t end)
  * - Find the memtype of all the pages in the range, look for any conflicts
  * - In case of no conflicts, set the new memtype for pages in the range
  */
-static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type,
-                                  unsigned long *new_type)
+static int reserve_ram_pages_type(u64 start, u64 end,
+                                  enum page_cache_mode req_type,
+                                  enum page_cache_mode *new_type)
 {
         struct page *page;
         u64 pfn;
 
-        if (req_type == _PAGE_CACHE_UC) {
+        if (req_type == _PAGE_CACHE_MODE_UC) {
                 /* We do not support strong UC */
                 WARN_ON_ONCE(1);
-                req_type = _PAGE_CACHE_UC_MINUS;
+                req_type = _PAGE_CACHE_MODE_UC_MINUS;
         }
 
         for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
-                unsigned long type;
+                enum page_cache_mode type;
 
                 page = pfn_to_page(pfn);
                 type = get_page_memtype(page);
                 if (type != -1) {
-                        printk(KERN_INFO "reserve_ram_pages_type failed [mem %#010Lx-%#010Lx], track 0x%lx, req 0x%lx\n",
+                        pr_info("reserve_ram_pages_type failed [mem %#010Lx-%#010Lx], track 0x%x, req 0x%x\n",
                                 start, end - 1, type, req_type);
                         if (new_type)
                                 *new_type = type;
@@ -258,21 +260,21 @@ static int free_ram_pages_type(u64 start, u64 end)
 
 /*
  * req_type typically has one of the:
- * - _PAGE_CACHE_WB
- * - _PAGE_CACHE_WC
- * - _PAGE_CACHE_UC_MINUS
- * - _PAGE_CACHE_UC
+ * - _PAGE_CACHE_MODE_WB
+ * - _PAGE_CACHE_MODE_WC
+ * - _PAGE_CACHE_MODE_UC_MINUS
+ * - _PAGE_CACHE_MODE_UC
  *
  * If new_type is NULL, function will return an error if it cannot reserve the
  * region with req_type. If new_type is non-NULL, function will return
  * available type in new_type in case of no error. In case of any error
  * it will return a negative return value.
  */
-int reserve_memtype(u64 start, u64 end, unsigned long req_type,
-                    unsigned long *new_type)
+int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
+                    enum page_cache_mode *new_type)
 {
         struct memtype *new;
-        unsigned long actual_type;
+        enum page_cache_mode actual_type;
         int is_range_ram;
         int err = 0;
 
@@ -281,10 +283,10 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
         if (!pat_enabled) {
                 /* This is identical to page table setting without PAT */
                 if (new_type) {
-                        if (req_type == _PAGE_CACHE_WC)
-                                *new_type = _PAGE_CACHE_UC_MINUS;
+                        if (req_type == _PAGE_CACHE_MODE_WC)
+                                *new_type = _PAGE_CACHE_MODE_UC_MINUS;
                         else
-                                *new_type = req_type & _PAGE_CACHE_MASK;
+                                *new_type = req_type;
                 }
                 return 0;
         }
@@ -292,7 +294,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
         /* Low ISA region is always mapped WB in page table. No need to track */
         if (x86_platform.is_untracked_pat_range(start, end)) {
                 if (new_type)
-                        *new_type = _PAGE_CACHE_WB;
+                        *new_type = _PAGE_CACHE_MODE_WB;
                 return 0;
         }
 
@@ -302,7 +304,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
          * tools and ACPI tools). Use WB request for WB memory and use
          * UC_MINUS otherwise.
          */
-        actual_type = pat_x_mtrr_type(start, end, req_type & _PAGE_CACHE_MASK);
+        actual_type = pat_x_mtrr_type(start, end, req_type);
 
         if (new_type)
                 *new_type = actual_type;
@@ -408,7 +410,7 @@ static enum page_cache_mode lookup_memtype(u64 paddr)
         if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
                 struct page *page;
                 page = pfn_to_page(paddr >> PAGE_SHIFT);
-                rettype = pgprot2cachemode(__pgprot(get_page_memtype(page)));
+                rettype = get_page_memtype(page);
                 /*
                  * -1 from get_page_memtype() implies RAM page is in its
                  * default state and not reserved, and hence of type WB
@@ -423,7 +425,7 @@ static enum page_cache_mode lookup_memtype(u64 paddr)
 
         entry = rbt_memtype_lookup(paddr);
         if (entry != NULL)
-                rettype = pgprot2cachemode(__pgprot(entry->type));
+                rettype = entry->type;
         else
                 rettype = _PAGE_CACHE_MODE_UC_MINUS;
 
@@ -447,18 +449,14 @@ int io_reserve_memtype(resource_size_t start, resource_size_t end,
         resource_size_t size = end - start;
         enum page_cache_mode req_type = *type;
         enum page_cache_mode new_type;
-        unsigned long new_prot;
         int ret;
 
         WARN_ON_ONCE(iomem_map_sanity_check(start, size));
 
-        ret = reserve_memtype(start, end, cachemode2protval(req_type),
-                                &new_prot);
+        ret = reserve_memtype(start, end, req_type, &new_type);
         if (ret)
                 goto out_err;
 
-        new_type = pgprot2cachemode(__pgprot(new_prot));
-
         if (!is_new_memtype_allowed(start, size, req_type, new_type))
                 goto out_free;
 
@@ -524,13 +522,13 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
                                 unsigned long size, pgprot_t *vma_prot)
 {
-        unsigned long flags = _PAGE_CACHE_WB;
+        enum page_cache_mode pcm = _PAGE_CACHE_MODE_WB;
 
         if (!range_is_allowed(pfn, size))
                 return 0;
 
         if (file->f_flags & O_DSYNC)
-                flags = _PAGE_CACHE_UC_MINUS;
+                pcm = _PAGE_CACHE_MODE_UC_MINUS;
 
 #ifdef CONFIG_X86_32
         /*
@@ -547,12 +545,12 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
               boot_cpu_has(X86_FEATURE_CYRIX_ARR) ||
               boot_cpu_has(X86_FEATURE_CENTAUR_MCR)) &&
             (pfn << PAGE_SHIFT) >= __pa(high_memory)) {
-                flags = _PAGE_CACHE_UC;
+                pcm = _PAGE_CACHE_MODE_UC;
         }
 #endif
 
         *vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
-                             flags);
+                             cachemode2protval(pcm));
         return 1;
 }
 
@@ -583,7 +581,7 @@ int kernel_map_sync_memtype(u64 base, unsigned long size,
                 printk(KERN_INFO "%s:%d ioremap_change_attr failed %s "
                         "for [mem %#010Lx-%#010Lx]\n",
                         current->comm, current->pid,
-                        cattr_name(cachemode2protval(pcm)),
+                        cattr_name(pcm),
                         base, (unsigned long long)(base + size-1));
                 return -EINVAL;
         }
@@ -600,8 +598,8 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
 {
         int is_ram = 0;
         int ret;
-        unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK);
-        unsigned long flags = want_flags;
+        enum page_cache_mode want_pcm = pgprot2cachemode(*vma_prot);
+        enum page_cache_mode pcm = want_pcm;
 
         is_ram = pat_pagerange_is_ram(paddr, paddr + size);
 
@@ -614,38 +612,36 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
                 if (!pat_enabled)
                         return 0;
 
-                flags = cachemode2protval(lookup_memtype(paddr));
-                if (want_flags != flags) {
+                pcm = lookup_memtype(paddr);
+                if (want_pcm != pcm) {
                         printk(KERN_WARNING "%s:%d map pfn RAM range req %s for [mem %#010Lx-%#010Lx], got %s\n",
                                 current->comm, current->pid,
-                                cattr_name(want_flags),
+                                cattr_name(want_pcm),
                                 (unsigned long long)paddr,
                                 (unsigned long long)(paddr + size - 1),
-                                cattr_name(flags));
+                                cattr_name(pcm));
                         *vma_prot = __pgprot((pgprot_val(*vma_prot) &
-                                              (~_PAGE_CACHE_MASK)) |
-                                             flags);
+                                             (~_PAGE_CACHE_MASK)) |
+                                             cachemode2protval(pcm));
                 }
                 return 0;
         }
 
-        ret = reserve_memtype(paddr, paddr + size, want_flags, &flags);
+        ret = reserve_memtype(paddr, paddr + size, want_pcm, &pcm);
         if (ret)
                 return ret;
 
-        if (flags != want_flags) {
+        if (pcm != want_pcm) {
                 if (strict_prot ||
-                    !is_new_memtype_allowed(paddr, size,
-                                pgprot2cachemode(__pgprot(want_flags)),
-                                pgprot2cachemode(__pgprot(flags)))) {
+                    !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
                         free_memtype(paddr, paddr + size);
                         printk(KERN_ERR "%s:%d map pfn expected mapping type %s"
                                 " for [mem %#010Lx-%#010Lx], got %s\n",
                                 current->comm, current->pid,
-                                cattr_name(want_flags),
+                                cattr_name(want_pcm),
                                 (unsigned long long)paddr,
                                 (unsigned long long)(paddr + size - 1),
-                                cattr_name(flags));
+                                cattr_name(pcm));
                         return -EINVAL;
                 }
                 /*
@@ -654,11 +650,10 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
                  */
                 *vma_prot = __pgprot((pgprot_val(*vma_prot) &
                                       (~_PAGE_CACHE_MASK)) |
-                                     flags);
+                                     cachemode2protval(pcm));
         }
 
-        if (kernel_map_sync_memtype(paddr, size,
-                                    pgprot2cachemode(__pgprot(flags))) < 0) {
+        if (kernel_map_sync_memtype(paddr, size, pcm) < 0) {
                 free_memtype(paddr, paddr + size);
                 return -EINVAL;
         }
@@ -799,7 +794,8 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 pgprot_t pgprot_writecombine(pgprot_t prot)
 {
         if (pat_enabled)
-                return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC);
+                return __pgprot(pgprot_val(prot) |
+                                cachemode2protval(_PAGE_CACHE_MODE_WC));
         else
                 return pgprot_noncached(prot);
 }
diff --git a/arch/x86/mm/pat_internal.h b/arch/x86/mm/pat_internal.h
index 77e5ba153fac..f6411620305d 100644
--- a/arch/x86/mm/pat_internal.h
+++ b/arch/x86/mm/pat_internal.h
@@ -10,30 +10,32 @@ struct memtype {
         u64                     start;
         u64                     end;
         u64                     subtree_max_end;
-        unsigned long           type;
+        enum page_cache_mode    type;
         struct rb_node          rb;
 };
 
-static inline char *cattr_name(unsigned long flags)
+static inline char *cattr_name(enum page_cache_mode pcm)
 {
-        switch (flags & _PAGE_CACHE_MASK) {
-        case _PAGE_CACHE_UC:            return "uncached";
-        case _PAGE_CACHE_UC_MINUS:      return "uncached-minus";
-        case _PAGE_CACHE_WB:            return "write-back";
-        case _PAGE_CACHE_WC:            return "write-combining";
-        default:                        return "broken";
+        switch (pcm) {
+        case _PAGE_CACHE_MODE_UC:               return "uncached";
+        case _PAGE_CACHE_MODE_UC_MINUS:         return "uncached-minus";
+        case _PAGE_CACHE_MODE_WB:               return "write-back";
+        case _PAGE_CACHE_MODE_WC:               return "write-combining";
+        case _PAGE_CACHE_MODE_WT:               return "write-through";
+        case _PAGE_CACHE_MODE_WP:               return "write-protected";
+        default:                                return "broken";
         }
 }
 
 #ifdef CONFIG_X86_PAT
 extern int rbt_memtype_check_insert(struct memtype *new,
-                                        unsigned long *new_type);
+                                        enum page_cache_mode *new_type);
 extern struct memtype *rbt_memtype_erase(u64 start, u64 end);
 extern struct memtype *rbt_memtype_lookup(u64 addr);
 extern int rbt_memtype_copy_nth_element(struct memtype *out, loff_t pos);
 #else
 static inline int rbt_memtype_check_insert(struct memtype *new,
-                                        unsigned long *new_type)
+                                        enum page_cache_mode *new_type)
 { return 0; }
 static inline struct memtype *rbt_memtype_erase(u64 start, u64 end)
 { return NULL; }
diff --git a/arch/x86/mm/pat_rbtree.c b/arch/x86/mm/pat_rbtree.c
index 415f6c4ced36..6582adcc8bd9 100644
--- a/arch/x86/mm/pat_rbtree.c
+++ b/arch/x86/mm/pat_rbtree.c
@@ -122,11 +122,12 @@ static struct memtype *memtype_rb_exact_match(struct rb_root *root,
 
 static int memtype_rb_check_conflict(struct rb_root *root,
                                 u64 start, u64 end,
-                                unsigned long reqtype, unsigned long *newtype)
+                                enum page_cache_mode reqtype,
+                                enum page_cache_mode *newtype)
 {
         struct rb_node *node;
         struct memtype *match;
-        int found_type = reqtype;
+        enum page_cache_mode found_type = reqtype;
 
         match = memtype_rb_lowest_match(&memtype_rbroot, start, end);
         if (match == NULL)
@@ -187,7 +188,8 @@ static void memtype_rb_insert(struct rb_root *root, struct memtype *newdata)
         rb_insert_augmented(&newdata->rb, root, &memtype_rb_augment_cb);
 }
 
-int rbt_memtype_check_insert(struct memtype *new, unsigned long *ret_type)
+int rbt_memtype_check_insert(struct memtype *new,
+                             enum page_cache_mode *ret_type)
 {
         int err = 0;