mm: make ptval_to_str() generally available

Patch series "mm: Drop pxd_ERROR()".

pxd_ERROR() macros have been provided by all platforms, which are very
much identical and can be dropped off completely if these pgtable printing
could be moved to callers in generic MM aka all pxd_clear_bad().

But first cleanups and re-organizations are required in some platforms
that are using these macros internally.  Afterwards
[pte|pmd|pud|p4d|pgd]_ERROR() macros have been completely dropped from the
entire tree.


This patch (of 8):

Move ptval_to_str() inside a header thus making the helper more generally
available for new users which are being added later.  While here, also
move another related string size macro PTVAL_STR_MAX inside the header as
well.

Link: https://lore.kernel.org/20260831054331.625505-1-anshuman.khandual@arm.com
Link: https://lore.kernel.org/20260831054331.625505-2-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: James Bottomley <james.bottomley@HansenPartnership.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 8c093c119e5a..e3c8ab96941c 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -2313,6 +2313,20 @@ static inline const char *pgtable_level_to_str(enum pgtable_level level)
 	}
 }
 
+void ptval_bytes_to_hex_str(char *buf, size_t buf_size, const void *entry, size_t entry_size);
+
+#define ptval_to_str(buf, val)								\
+	do {										\
+		auto __val = (val);							\
+											\
+		ptval_bytes_to_hex_str((buf), sizeof(buf), &__val, sizeof(__val));	\
+	} while (0)
+
+#if defined(__SIZEOF_INT128__)
+#define PTVAL_STR_MAX	(32 + 1) /* Max 128-bit value in hex + NUL */
+#else
+#define PTVAL_STR_MAX	(16 + 1) /* Max 64-bit value in hex + NUL */
+#endif
 #endif /* !__ASSEMBLER__ */
 
 #if !defined(MAX_POSSIBLE_PHYSMEM_BITS) && !defined(CONFIG_64BIT)