1 files changed, 97 insertions, 8 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 7b79f6be4e7d..7d9517abc9af 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -9,6 +9,8 @@
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
 
 #include <asm/e820.h>
 #include <asm/processor.h>
@@ -17,6 +19,7 @@
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/proto.h>
+#include <asm/pat.h>
 
 /*
  * The current flushing context - we pass it instead of 5 arguments:
@@ -28,6 +31,7 @@ struct cpa_data {
         int             numpages;
         int             flushtlb;
         unsigned long   pfn;
+        unsigned        force_split : 1;
 };
 
 #ifdef CONFIG_X86_64
@@ -259,6 +263,9 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
         int i, do_split = 1;
         unsigned int level;
 
+        if (cpa->force_split)
+                return 1;
+
         spin_lock_irqsave(&pgd_lock, flags);
         /*
          * Check for races, another CPU might have split this page
@@ -693,7 +700,8 @@ static inline int cache_attr(pgprot_t attr)
 }
 
 static int change_page_attr_set_clr(unsigned long addr, int numpages,
-                                    pgprot_t mask_set, pgprot_t mask_clr)
+                                    pgprot_t mask_set, pgprot_t mask_clr,
+                                    int force_split)
 {
         struct cpa_data cpa;
         int ret, cache, checkalias;
@@ -704,7 +712,7 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages,
          */
         mask_set = canon_pgprot(mask_set);
         mask_clr = canon_pgprot(mask_clr);
-        if (!pgprot_val(mask_set) && !pgprot_val(mask_clr))
+        if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
                 return 0;
 
         /* Ensure we are PAGE_SIZE aligned */
@@ -721,6 +729,7 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages,
         cpa.mask_set = mask_set;
         cpa.mask_clr = mask_clr;
         cpa.flushtlb = 0;
+        cpa.force_split = force_split;
 
         /* No alias checking for _NX bit modifications */
         checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
@@ -759,26 +768,61 @@ out:
 static inline int change_page_attr_set(unsigned long addr, int numpages,
                                        pgprot_t mask)
 {
-        return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0));
+        return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0);
 }
 
 static inline int change_page_attr_clear(unsigned long addr, int numpages,
                                          pgprot_t mask)
 {
-        return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask);
+        return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0);
 }
 
-int set_memory_uc(unsigned long addr, int numpages)
+int _set_memory_uc(unsigned long addr, int numpages)
 {
         return change_page_attr_set(addr, numpages,
-                                    __pgprot(_PAGE_PCD));
+                                    __pgprot(_PAGE_CACHE_UC));
+}
+
+int set_memory_uc(unsigned long addr, int numpages)
+{
+        if (reserve_memtype(addr, addr + numpages * PAGE_SIZE,
+                            _PAGE_CACHE_UC, NULL))
+                return -EINVAL;
+
+        return _set_memory_uc(addr, numpages);
 }
 EXPORT_SYMBOL(set_memory_uc);
 
-int set_memory_wb(unsigned long addr, int numpages)
+int _set_memory_wc(unsigned long addr, int numpages)
+{
+        return change_page_attr_set(addr, numpages,
+                                    __pgprot(_PAGE_CACHE_WC));
+}
+
+int set_memory_wc(unsigned long addr, int numpages)
+{
+        if (!pat_wc_enabled)
+                return set_memory_uc(addr, numpages);
+
+        if (reserve_memtype(addr, addr + numpages * PAGE_SIZE,
+                _PAGE_CACHE_WC, NULL))
+                return -EINVAL;
+
+        return _set_memory_wc(addr, numpages);
+}
+EXPORT_SYMBOL(set_memory_wc);
+
+int _set_memory_wb(unsigned long addr, int numpages)
 {
         return change_page_attr_clear(addr, numpages,
-                                      __pgprot(_PAGE_PCD | _PAGE_PWT));
+                                      __pgprot(_PAGE_CACHE_MASK));
+}
+
+int set_memory_wb(unsigned long addr, int numpages)
+{
+        free_memtype(addr, addr + numpages * PAGE_SIZE);
+
+        return _set_memory_wb(addr, numpages);
 }
 EXPORT_SYMBOL(set_memory_wb);
 
@@ -809,6 +853,12 @@ int set_memory_np(unsigned long addr, int numpages)
         return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT));
 }
 
+int set_memory_4k(unsigned long addr, int numpages)
+{
+        return change_page_attr_set_clr(addr, numpages, __pgprot(0),
+                                        __pgprot(0), 1);
+}
+
 int set_pages_uc(struct page *page, int numpages)
 {
         unsigned long addr = (unsigned long)page_address(page);
@@ -918,6 +968,45 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
         cpa_fill_pool(NULL);
 }
 
+#ifdef CONFIG_DEBUG_FS
+static int dpa_show(struct seq_file *m, void *v)
+{
+        seq_puts(m, "DEBUG_PAGEALLOC\n");
+        seq_printf(m, "pool_size     : %lu\n", pool_size);
+        seq_printf(m, "pool_pages    : %lu\n", pool_pages);
+        seq_printf(m, "pool_low      : %lu\n", pool_low);
+        seq_printf(m, "pool_used     : %lu\n", pool_used);
+        seq_printf(m, "pool_failed   : %lu\n", pool_failed);
+
+        return 0;
+}
+
+static int dpa_open(struct inode *inode, struct file *filp)
+{
+        return single_open(filp, dpa_show, NULL);
+}
+
+static const struct file_operations dpa_fops = {
+        .open           = dpa_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
+int __init debug_pagealloc_proc_init(void)
+{
+        struct dentry *de;
+
+        de = debugfs_create_file("debug_pagealloc", 0600, NULL, NULL,
+                                 &dpa_fops);
+        if (!de)
+                return -ENOMEM;
+
+        return 0;
+}
+__initcall(debug_pagealloc_proc_init);
+#endif
+
 #ifdef CONFIG_HIBERNATION
 
 bool kernel_page_present(struct page *page)