[PATCH v4 2/5] arm64: non leaf ptdump support

[Maxwell Bland]

Separate the pte_bits used in ptdump from pxd_bits used by pmd, p4d,
pud, and pgd descriptors, thereby adding support for printing key
intermediate directory protection bits, such as PXNTable, and enable the
associated support Kconfig option.

Signed-off-by: Maxwell Bland <mbland at motorola.com>
---
 arch/arm64/Kconfig     |   1 +
 arch/arm64/mm/ptdump.c | 140 ++++++++++++++++++++++++++++++++++++-----
 2 files changed, 125 insertions(+), 16 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 5d91259ee7b5..f4c3290160db 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -98,6 +98,7 @@ config ARM64
 	select ARCH_SUPPORTS_NUMA_BALANCING
 	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
 	select ARCH_SUPPORTS_PER_VMA_LOCK
+	select ARCH_SUPPORTS_NON_LEAF_PTDUMP
 	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
 	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
 	select ARCH_WANT_DEFAULT_BPF_JIT
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index 6986827e0d64..8f0b459c13ed 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -24,6 +24,7 @@
 #include <asm/memory.h>
 #include <asm/pgtable-hwdef.h>
 #include <asm/ptdump.h>
+#include <asm/pgalloc.h>
 
 
 #define pt_dump_seq_printf(m, fmt, args...)	\
@@ -105,11 +106,6 @@ static const struct prot_bits pte_bits[] = {
 		.val	= PTE_CONT,
 		.set	= "CON",
 		.clear	= "   ",
-	}, {
-		.mask	= PTE_TABLE_BIT,
-		.val	= PTE_TABLE_BIT,
-		.set	= "   ",
-		.clear	= "BLK",
 	}, {
 		.mask	= PTE_UXN,
 		.val	= PTE_UXN,
@@ -143,34 +139,129 @@ static const struct prot_bits pte_bits[] = {
 	}
 };
 
+static const struct prot_bits pxd_bits[] = {
+	{
+		.mask	= PMD_SECT_VALID,
+		.val	= PMD_SECT_VALID,
+		.set	= " ",
+		.clear	= "F",
+	}, {
+		.mask	= PMD_TABLE_BIT,
+		.val	= PMD_TABLE_BIT,
+		.set	= "TBL",
+		.clear	= "BLK",
+	}, {
+		.mask	= PMD_SECT_USER,
+		.val	= PMD_SECT_USER,
+		.set	= "USR",
+		.clear	= "   ",
+	}, {
+		.mask	= PMD_SECT_RDONLY,
+		.val	= PMD_SECT_RDONLY,
+		.set	= "ro",
+		.clear	= "RW",
+	}, {
+		.mask	= PMD_SECT_S,
+		.val	= PMD_SECT_S,
+		.set	= "SHD",
+		.clear	= "   ",
+	}, {
+		.mask	= PMD_SECT_AF,
+		.val	= PMD_SECT_AF,
+		.set	= "AF",
+		.clear	= "  ",
+	}, {
+		.mask	= PMD_SECT_NG,
+		.val	= PMD_SECT_NG,
+		.set	= "NG",
+		.clear	= "  ",
+	}, {
+		.mask	= PMD_SECT_CONT,
+		.val	= PMD_SECT_CONT,
+		.set	= "CON",
+		.clear	= "   ",
+	}, {
+		.mask	= PMD_SECT_PXN,
+		.val	= PMD_SECT_PXN,
+		.set	= "NX",
+		.clear	= "x ",
+	}, {
+		.mask	= PMD_SECT_UXN,
+		.val	= PMD_SECT_UXN,
+		.set	= "UXN",
+		.clear	= "   ",
+	}, {
+		.mask	= PMD_TABLE_PXN,
+		.val	= PMD_TABLE_PXN,
+		.set	= "NXTbl",
+		.clear	= "     ",
+	}, {
+		.mask	= PMD_TABLE_UXN,
+		.val	= PMD_TABLE_UXN,
+		.set	= "UXNTbl",
+		.clear	= "      ",
+	}, {
+		.mask	= PTE_GP,
+		.val	= PTE_GP,
+		.set	= "GP",
+		.clear	= "  ",
+	}, {
+		.mask	= PMD_ATTRINDX_MASK,
+		.val	= PMD_ATTRINDX(MT_DEVICE_nGnRnE),
+		.set	= "DEVICE/nGnRnE",
+	}, {
+		.mask	= PMD_ATTRINDX_MASK,
+		.val	= PMD_ATTRINDX(MT_DEVICE_nGnRE),
+		.set	= "DEVICE/nGnRE",
+	}, {
+		.mask	= PMD_ATTRINDX_MASK,
+		.val	= PMD_ATTRINDX(MT_NORMAL_NC),
+		.set	= "MEM/NORMAL-NC",
+	}, {
+		.mask	= PMD_ATTRINDX_MASK,
+		.val	= PMD_ATTRINDX(MT_NORMAL),
+		.set	= "MEM/NORMAL",
+	}, {
+		.mask	= PMD_ATTRINDX_MASK,
+		.val	= PMD_ATTRINDX(MT_NORMAL_TAGGED),
+		.set	= "MEM/NORMAL-TAGGED",
+	}
+};
+
 struct pg_level {
 	const struct prot_bits *bits;
 	char name[4];
 	int num;
 	u64 mask;
+	unsigned long size;
 };
 
 static struct pg_level pg_level[] __ro_after_init = {
 	{ /* pgd */
 		.name	= "PGD",
-		.bits	= pte_bits,
-		.num	= ARRAY_SIZE(pte_bits),
+		.bits	= pxd_bits,
+		.num	= ARRAY_SIZE(pxd_bits),
+		.size	= PGDIR_SIZE,
 	}, { /* p4d */
 		.name	= "P4D",
-		.bits	= pte_bits,
-		.num	= ARRAY_SIZE(pte_bits),
+		.bits	= pxd_bits,
+		.num	= ARRAY_SIZE(pxd_bits),
+		.size	= P4D_SIZE,
 	}, { /* pud */
 		.name	= "PUD",
-		.bits	= pte_bits,
-		.num	= ARRAY_SIZE(pte_bits),
+		.bits	= pxd_bits,
+		.num	= ARRAY_SIZE(pxd_bits),
+		.size	= PUD_SIZE,
 	}, { /* pmd */
 		.name	= "PMD",
-		.bits	= pte_bits,
-		.num	= ARRAY_SIZE(pte_bits),
+		.bits	= pxd_bits,
+		.num	= ARRAY_SIZE(pxd_bits),
+		.size	= PMD_SIZE,
 	}, { /* pte */
 		.name	= "PTE",
 		.bits	= pte_bits,
 		.num	= ARRAY_SIZE(pte_bits),
+		.size	= PAGE_SIZE
 	},
 };
 
@@ -251,10 +342,27 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
 			note_prot_wx(st, addr);
 		}
 
-		pt_dump_seq_printf(st->seq, "0x%016lx-0x%016lx   ",
-				   st->start_address, addr);
+		/*
+		 * Non-leaf entries use a fixed size for their range
+		 * specification, whereas leaf entries are grouped by
+		 * attributes and may not have a range larger than the type
+		 * specifier.
+		 */
+		if (st->start_address == addr) {
+			if (check_add_overflow(addr, pg_level[st->level].size,
+					       &delta))
+				delta = ULONG_MAX - addr + 1;
+			else
+				delta = pg_level[st->level].size;
+			pt_dump_seq_printf(st->seq, "0x%016lx-0x%016lx   ",
+					   addr, addr + delta);
+		} else {
+			delta = (addr - st->start_address);
+			pt_dump_seq_printf(st->seq, "0x%016lx-0x%016lx   ",
+					   st->start_address, addr);
+		}
 
-		delta = (addr - st->start_address) >> 10;
+		delta >>= 10;
 		while (!(delta & 1023) && unit[1]) {
 			delta >>= 10;
 			unit++;
-- 
2.39.2