arm64: ptdump: Use the ptdump description from a local context

Rename the attributes description array to allow the parsing method
to use the description from a local context. To be able to do this,
store a pointer to the description array in the state structure. This
will allow for the later introduced callers (stage_2 ptdump) to specify
their own page table description format to the ptdump parser.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240909124721.1672199-4-sebastianene@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Sebastian Ene

arch/arm64/include/asm/ptdump.h

@@ -45,6 +45,7 @@ struct ptdump_pg_level {
  */
 struct ptdump_pg_state {
 	struct ptdump_state ptdump;
+	struct ptdump_pg_level *pg_level;
 	struct seq_file *seq;
 	const struct addr_marker *marker;
 	const struct mm_struct *mm;

arch/arm64/mm/ptdump.c

@@ -117,7 +117,7 @@ static const struct ptdump_prot_bits pte_bits[] = {
 	}
 };
 
-static struct ptdump_pg_level pg_level[] __ro_after_init = {
+static struct ptdump_pg_level kernel_pg_levels[] __ro_after_init = {
 	{ /* pgd */
 		.name	= "PGD",
 		.bits	= pte_bits,
@@ -192,6 +192,7 @@ void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
 	       u64 val)
 {
 	struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump);
+	struct ptdump_pg_level *pg_level = st->pg_level;
 	static const char units[] = "KMGTPE";
 	u64 prot = 0;
 
@@ -262,6 +263,7 @@ void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
 		.seq = s,
 		.marker = info->markers,
 		.mm = info->mm,
+		.pg_level = &kernel_pg_levels[0],
 		.level = -1,
 		.ptdump = {
 			.note_page = note_page,
@@ -279,10 +281,10 @@ static void __init ptdump_initialize(void)
 {
 	unsigned i, j;
 
-	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
-		if (pg_level[i].bits)
-			for (j = 0; j < pg_level[i].num; j++)
-				pg_level[i].mask |= pg_level[i].bits[j].mask;
+	for (i = 0; i < ARRAY_SIZE(kernel_pg_levels); i++)
+		if (kernel_pg_levels[i].bits)
+			for (j = 0; j < kernel_pg_levels[i].num; j++)
+				kernel_pg_levels[i].mask |= kernel_pg_levels[i].bits[j].mask;
 }
 
 static struct ptdump_info kernel_ptdump_info __ro_after_init = {
@@ -297,6 +299,7 @@ bool ptdump_check_wx(void)
 			{ 0, NULL},
 			{ -1, NULL},
 		},
+		.pg_level = &kernel_pg_levels[0],
 		.level = -1,
 		.check_wx = true,
 		.ptdump = {