Re: [PATCH] microblaze: Make virt_to_pfn() a static inline

From: Michal Simek
Date: Wed Aug 23 2023 - 03:30:05 EST




On 8/8/23 10:40, Linus Walleij wrote:
Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

Move the function down in the file so __pa() exists in our
scope, and it compiles. This in turn requires moving __pa()
as it depends on __virt_to_phys() that was below. (Lazy macro
evaluation conflicts with strict function ordering.)

Make a symmetric change to pfn_to_virt() so we have type
checking both ways.

Due to this the <asm/page.h> file being included into some
assembly files, some further inclusion guards are needed
to make sure assembly keeps compiling.

Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
arch/microblaze/include/asm/page.h | 27 +++++++++++++++++++--------
1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/arch/microblaze/include/asm/page.h b/arch/microblaze/include/asm/page.h
index 337f23eabc71..86a4ce07c192 100644
--- a/arch/microblaze/include/asm/page.h
+++ b/arch/microblaze/include/asm/page.h
@@ -99,9 +99,6 @@ extern int page_is_ram(unsigned long pfn);
# define phys_to_pfn(phys) (PFN_DOWN(phys))
# define pfn_to_phys(pfn) (PFN_PHYS(pfn))
-# define virt_to_pfn(vaddr) (phys_to_pfn((__pa(vaddr))))
-# define pfn_to_virt(pfn) __va(pfn_to_phys((pfn)))
-
# define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
# define page_to_virt(page) __va(page_to_pfn(page) << PAGE_SHIFT)
# define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
@@ -109,11 +106,6 @@ extern int page_is_ram(unsigned long pfn);
# define ARCH_PFN_OFFSET (memory_start >> PAGE_SHIFT)
# endif /* __ASSEMBLY__ */
-#define virt_addr_valid(vaddr) (pfn_valid(virt_to_pfn(vaddr)))
-
-# define __pa(x) __virt_to_phys((unsigned long)(x))
-# define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
-
/* Convert between virtual and physical address for MMU. */
/* Handle MicroBlaze processor with virtual memory. */
#define __virt_to_phys(addr) \
@@ -125,6 +117,25 @@ extern int page_is_ram(unsigned long pfn);
#define tovirt(rd, rs) \
addik rd, rs, (CONFIG_KERNEL_START - CONFIG_KERNEL_BASE_ADDR)
+#ifndef __ASSEMBLY__
+
+# define __pa(x) __virt_to_phys((unsigned long)(x))
+# define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
+
+static inline unsigned long virt_to_pfn(const void *vaddr)
+{
+ return phys_to_pfn(__pa(vaddr));
+}
+
+static inline const void *pfn_to_virt(unsigned long pfn)
+{
+ return __va(pfn_to_phys((pfn)));
+}
+
+#define virt_addr_valid(vaddr) (pfn_valid(virt_to_pfn(vaddr)))
+
+#endif /* __ASSEMBLY__ */
+
#define TOPHYS(addr) __virt_to_phys(addr)
#endif /* __KERNEL__ */

---
base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5
change-id: 20230808-virt-to-phys-microblaze-4afdf2bcf96c

Best regards,

Applied.
M

--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Xilinx Microblaze
Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP/Versal ARM64 SoCs
U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP/Versal/Versal NET SoCs
TF-A maintainer - Xilinx ZynqMP/Versal/Versal NET SoCs