[PATCH 2/6] x86/mm: Introduce _set_memory_prot()

Logan Gunthorpe
2019-12-09T19:14:04Z

For use in the 32bit arch_add_memory() to set the pgprot type of the
memory to add.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
arch/x86/include/asm/set_memory.h | 1 +
arch/x86/mm/pageattr.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 2ee8e469dcf5..d728c2f3ad96 100644
--- a/arch/x86/include/asm/set_memory.h
+++ b/arch/x86/include/asm/set_memory.h
@@ -34,6 +34,7 @@
* The caller is required to take care of these.
*/

+int _set_memory_prot(unsigned long addr, int numpages, pgprot_t prot);
int _set_memory_uc(unsigned long addr, int numpages);
int _set_memory_wc(unsigned long addr, int numpages);
int _set_memory_wt(unsigned long addr, int numpages);
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 0d09cc5aad61..024e3ddf494d 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -1781,6 +1781,13 @@ static inline int cpa_clear_pages_array(struct page **pages, int numpages,
CPA_PAGES_ARRAY, pages);
}

+int _set_memory_prot(unsigned long addr, int numpages, pgprot_t prot)
+{
+ return change_page_attr_set_clr(&addr, numpages, prot,
+ __pgprot(~pgprot_val(prot)), 0, 0,
+ NULL);
+}
+
int _set_memory_uc(unsigned long addr, int numpages)
{
/*
--
2.20.1