[PATCH V6 13/18] x86: Use new cache mode type in memtype related functions

From: Juergen Gross
Date: Mon Nov 03 2014 - 08:04:51 EST

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@xxxxxxxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/include/asm/cacheflush.h | 38 ++++++++------
arch/x86/include/asm/pat.h | 2 +-
arch/x86/mm/ioremap.c | 5 +-
arch/x86/mm/pageattr.c | 9 ++--
arch/x86/mm/pat.c | 102 ++++++++++++++++++--------------------
arch/x86/mm/pat_internal.h | 22 ++++----
arch/x86/mm/pat_rbtree.c | 8 +--
7 files changed, 96 insertions(+), 90 deletions(-)

diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h
index 9863ee3..157644b 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 d35ee2d..150407a 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 f31507f..8832e51 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 9f7e1b4..de807c9 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 8f68a83..ef75f3f 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 77e5ba1..f641162 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 415f6c4..6582adc 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;

--
1.8.4.5

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