diff options
| -rw-r--r-- | arch/x86_64/mm/pageattr.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c index efe5af14c7db..531ad21447b1 100644 --- a/arch/x86_64/mm/pageattr.c +++ b/arch/x86_64/mm/pageattr.c @@ -45,6 +45,13 @@ static struct page *split_large_page(unsigned long address, pgprot_t prot, pte_t *pbase; if (!base) return NULL; + /* + * page_private is used to track the number of entries in + * the page table page have non standard attributes. + */ + SetPagePrivate(base); + page_private(base) = 0; + address = __pa(address); addr = address & LARGE_PAGE_MASK; pbase = (pte_t *)page_address(base); @@ -124,8 +131,8 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot, set_pte(kpte, pfn_pte(pfn, prot)); } else { /* - * split_large_page will take the reference for this change_page_attr - * on the split page. + * split_large_page will take the reference for this + * change_page_attr on the split page. */ struct page *split; @@ -137,23 +144,20 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot, set_pte(kpte,mk_pte(split, ref_prot2)); kpte_page = split; } - get_page(kpte_page); + page_private(kpte_page)++; } else if ((kpte_flags & _PAGE_PSE) == 0) { set_pte(kpte, pfn_pte(pfn, ref_prot)); - __put_page(kpte_page); + BUG_ON(page_private(kpte_page) == 0); + page_private(kpte_page)--; } else BUG(); /* on x86-64 the direct mapping set at boot is not using 4k pages */ BUG_ON(PageReserved(kpte_page)); - switch (page_count(kpte_page)) { - case 1: + if (page_private(kpte_page) == 0) { save_page(kpte_page); revert_page(address, ref_prot); - break; - case 0: - BUG(); /* memleak and failed 2M page regeneration */ } return 0; } @@ -216,6 +220,7 @@ void global_flush_tlb(void) while (dpage) { struct page *tmp = dpage; dpage = (struct page *)dpage->lru.next; + ClearPagePrivate(tmp); __free_page(tmp); } } |