[RFC PATCH v3 1/6] arch: introduce set_direct_map_valid_noflush()

[Patrick Roy <roypat@amazon.co.uk>]

From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>

From: Mike Rapoport (Microsoft) <rppt@kernel.org>

Add an API that will allow updates of the direct/linear map for a set of
physically contiguous pages.

It will be used in the following patches.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Patrick Roy <roypat@amazon.co.uk>
---
 arch/arm64/include/asm/set_memory.h     |  1 +
 arch/arm64/mm/pageattr.c                | 10 ++++++++++
 arch/loongarch/include/asm/set_memory.h |  1 +
 arch/loongarch/mm/pageattr.c            | 21 +++++++++++++++++++++
 arch/riscv/include/asm/set_memory.h     |  1 +
 arch/riscv/mm/pageattr.c                | 15 +++++++++++++++
 arch/s390/include/asm/set_memory.h      |  1 +
 arch/s390/mm/pageattr.c                 | 11 +++++++++++
 arch/x86/include/asm/set_memory.h       |  1 +
 arch/x86/mm/pat/set_memory.c            |  8 ++++++++
 include/linux/set_memory.h              |  6 ++++++
 11 files changed, 76 insertions(+)

diff --git a/arch/arm64/include/asm/set_memory.h b/arch/arm64/include/asm/set_memory.h
index 917761feeffdd..98088c043606a 100644
--- a/arch/arm64/include/asm/set_memory.h
+++ b/arch/arm64/include/asm/set_memory.h
@@ -13,6 +13,7 @@ int set_memory_valid(unsigned long addr, int numpages, int enable);
 
 int set_direct_map_invalid_noflush(struct page *page);
 int set_direct_map_default_noflush(struct page *page);
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid);
 bool kernel_page_present(struct page *page);
 
 #endif /* _ASM_ARM64_SET_MEMORY_H */
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 0e270a1c51e64..01225900293ac 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -192,6 +192,16 @@ int set_direct_map_default_noflush(struct page *page)
 				   PAGE_SIZE, change_page_range, &data);
 }
 
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	unsigned long addr = (unsigned long)page_address(page);
+
+	if (!can_set_direct_map())
+		return 0;
+
+	return set_memory_valid(addr, nr, valid);
+}
+
 #ifdef CONFIG_DEBUG_PAGEALLOC
 void __kernel_map_pages(struct page *page, int numpages, int enable)
 {
diff --git a/arch/loongarch/include/asm/set_memory.h b/arch/loongarch/include/asm/set_memory.h
index d70505b6676cb..55dfaefd02c8a 100644
--- a/arch/loongarch/include/asm/set_memory.h
+++ b/arch/loongarch/include/asm/set_memory.h
@@ -17,5 +17,6 @@ int set_memory_rw(unsigned long addr, int numpages);
 bool kernel_page_present(struct page *page);
 int set_direct_map_default_noflush(struct page *page);
 int set_direct_map_invalid_noflush(struct page *page);
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid);
 
 #endif /* _ASM_LOONGARCH_SET_MEMORY_H */
diff --git a/arch/loongarch/mm/pageattr.c b/arch/loongarch/mm/pageattr.c
index ffd8d76021d47..f14b40c968b48 100644
--- a/arch/loongarch/mm/pageattr.c
+++ b/arch/loongarch/mm/pageattr.c
@@ -216,3 +216,24 @@ int set_direct_map_invalid_noflush(struct page *page)
 
 	return __set_memory(addr, 1, __pgprot(0), __pgprot(_PAGE_PRESENT | _PAGE_VALID));
 }
+
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	unsigned long addr = (unsigned long)page_address(page);
+	pgprot_t set, clear;
+
+	return __set_memory((unsigned long)page_address(page), nr, set, clear);
+
+	if (addr < vm_map_base)
+		return 0;
+
+	if (valid) {
+		set = PAGE_KERNEL;
+		clear = __pgprot(0);
+	} else {
+		set = __pgprot(0);
+		clear = __pgprot(_PAGE_PRESENT | _PAGE_VALID);
+	}
+
+	return __set_memory(addr, 1, set, clear);
+}
diff --git a/arch/riscv/include/asm/set_memory.h b/arch/riscv/include/asm/set_memory.h
index ab92fc84e1fc9..ea263d3683ef6 100644
--- a/arch/riscv/include/asm/set_memory.h
+++ b/arch/riscv/include/asm/set_memory.h
@@ -42,6 +42,7 @@ static inline int set_kernel_memory(char *startp, char *endp,
 
 int set_direct_map_invalid_noflush(struct page *page);
 int set_direct_map_default_noflush(struct page *page);
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid);
 bool kernel_page_present(struct page *page);
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/riscv/mm/pageattr.c b/arch/riscv/mm/pageattr.c
index 271d01a5ba4da..d815448758a19 100644
--- a/arch/riscv/mm/pageattr.c
+++ b/arch/riscv/mm/pageattr.c
@@ -386,6 +386,21 @@ int set_direct_map_default_noflush(struct page *page)
 			    PAGE_KERNEL, __pgprot(_PAGE_EXEC));
 }
 
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	pgprot_t set, clear;
+
+	if (valid) {
+		set = PAGE_KERNEL;
+		clear = __pgprot(_PAGE_EXEC);
+	} else {
+		set = __pgprot(0);
+		clear = __pgprot(_PAGE_PRESENT);
+	}
+
+	return __set_memory((unsigned long)page_address(page), nr, set, clear);
+}
+
 #ifdef CONFIG_DEBUG_PAGEALLOC
 static int debug_pagealloc_set_page(pte_t *pte, unsigned long addr, void *data)
 {
diff --git a/arch/s390/include/asm/set_memory.h b/arch/s390/include/asm/set_memory.h
index 06fbabe2f66c9..240bcfbdcdcec 100644
--- a/arch/s390/include/asm/set_memory.h
+++ b/arch/s390/include/asm/set_memory.h
@@ -62,5 +62,6 @@ __SET_MEMORY_FUNC(set_memory_4k, SET_MEMORY_4K)
 
 int set_direct_map_invalid_noflush(struct page *page);
 int set_direct_map_default_noflush(struct page *page);
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid);
 
 #endif
diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
index 5f805ad42d4c3..4c7ee74aa130d 100644
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -406,6 +406,17 @@ int set_direct_map_default_noflush(struct page *page)
 	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_DEF);
 }
 
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	unsigned long flags;
+
+	if (valid)
+		flags = SET_MEMORY_DEF;
+	else
+		flags = SET_MEMORY_INV;
+
+	return __set_memory((unsigned long)page_to_virt(page), nr, flags);
+}
 #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE)
 
 static void ipte_range(pte_t *pte, unsigned long address, int nr)
diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h
index 4b2abce2e3e7d..cc62ef70ccc0a 100644
--- a/arch/x86/include/asm/set_memory.h
+++ b/arch/x86/include/asm/set_memory.h
@@ -89,6 +89,7 @@ int set_pages_rw(struct page *page, int numpages);
 
 int set_direct_map_invalid_noflush(struct page *page);
 int set_direct_map_default_noflush(struct page *page);
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid);
 bool kernel_page_present(struct page *page);
 
 extern int kernel_set_to_readonly;
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 44f7b2ea6a073..069e421c22474 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -2444,6 +2444,14 @@ int set_direct_map_default_noflush(struct page *page)
 	return __set_pages_p(page, 1);
 }
 
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	if (valid)
+		return __set_pages_p(page, nr);
+
+	return __set_pages_np(page, nr);
+}
+
 #ifdef CONFIG_DEBUG_PAGEALLOC
 void __kernel_map_pages(struct page *page, int numpages, int enable)
 {
diff --git a/include/linux/set_memory.h b/include/linux/set_memory.h
index e7aec20fb44f1..3030d9245f5ac 100644
--- a/include/linux/set_memory.h
+++ b/include/linux/set_memory.h
@@ -34,6 +34,12 @@ static inline int set_direct_map_default_noflush(struct page *page)
 	return 0;
 }
 
+static inline int set_direct_map_valid_noflush(struct page *page,
+					       unsigned nr, bool valid)
+{
+	return 0;
+}
+
 static inline bool kernel_page_present(struct page *page)
 {
 	return true;

base-commit: 5cb1659f412041e4780f2e8ee49b2e03728a2ba6
-- 
2.47.0