arch: introduce set_direct_map_valid_noflush()

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.

Link: https://lkml.kernel.org/r/20241023162711.2579610-6-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: kdevops <kdevops@lists.linux.dev>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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 */

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)
 {

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 */

arch/loongarch/mm/pageattr.c

@@ -216,3 +216,22 @@ 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;
+
+	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);
+}

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__ */

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)
 {

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

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)

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;

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)
 {

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;