[RFC PATCH v2 15/19] x86/mm/cpa: Add set_memory_pks()

[Rick Edgecombe]

Add function for setting PKS key on kernel memory.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
---
 arch/x86/include/asm/set_memory.h | 1 +
 arch/x86/mm/pat/set_memory.c      | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h
index e0516651698a..1ba2fb45ed05 100644
--- a/arch/x86/include/asm/set_memory.h
+++ b/arch/x86/include/asm/set_memory.h
@@ -52,6 +52,7 @@ int set_memory_decrypted(unsigned long addr, int numpages);
 int set_memory_np_noalias(unsigned long addr, int numpages);
 int set_memory_nonglobal(unsigned long addr, int numpages);
 int set_memory_global(unsigned long addr, int numpages);
+int set_memory_pks(unsigned long addr, int numpages, int key);
 
 int set_pages_array_uc(struct page **pages, int addrinarray);
 int set_pages_array_wc(struct page **pages, int addrinarray);
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index c51792a797cb..dc704e8da032 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -1922,6 +1922,13 @@ int set_memory_wb(unsigned long addr, int numpages)
 }
 EXPORT_SYMBOL(set_memory_wb);
 
+int set_memory_pks(unsigned long addr, int numpages, int key)
+{
+	return change_page_attr_set_clr(&addr, numpages, __pgprot(_PAGE_PKEY(key)),
+					__pgprot(_PAGE_PKEY(0xF & ~(unsigned int)key)),
+					0, 0, NULL);
+}
+
 int set_memory_x(unsigned long addr, int numpages)
 {
 	if (!(__supported_pte_mask & _PAGE_NX))
-- 
2.17.1