crash/0003-arm64-Introduction-of-support-for-16K-page-with-3-le.patch

From 93d7f647c45b80b584db815f78b7130508642c60 Mon Sep 17 00:00:00 2001
From: Kuan-Ying Lee <kuan-ying.lee@canonical.com>
Date: Sat, 13 Jul 2024 21:22:52 +0800
Subject: [PATCH 3/5] arm64: Introduction of support for 16K page with 3-level
 table support

Introduction of ARM64 support for 16K page size with 3-level page
table and 47 VA bits.

Signed-off-by: Kuan-Ying Lee <kuan-ying.lee@canonical.com>
---
 arm64.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 defs.h  |  16 ++++++++
 2 files changed, 126 insertions(+), 4 deletions(-)

diff --git a/arm64.c b/arm64.c
index 78e6609..067c879 100644
--- a/arm64.c
+++ b/arm64.c
@@ -42,6 +42,7 @@ static int arm64_kvtop(struct task_context *, ulong, physaddr_t *, int);
 static int arm64_uvtop(struct task_context *, ulong, physaddr_t *, int);
 static int arm64_vtop_2level_64k(ulong, ulong, physaddr_t *, int);
 static int arm64_vtop_3level_64k(ulong, ulong, physaddr_t *, int);
+static int arm64_vtop_3level_16k(ulong, ulong, physaddr_t *, int);
 static int arm64_vtop_3level_4k(ulong, ulong, physaddr_t *, int);
 static int arm64_vtop_4level_4k(ulong, ulong, physaddr_t *, int);
 static ulong arm64_get_task_pgd(ulong);
@@ -262,8 +263,7 @@ arm64_init(int when)
 				machdep->pagesize = 4096;
 				break;
 			case 2:
-				/* TODO: machdep->pagesize = 16384; */
-				error(FATAL, "16K pages not supported.");
+				machdep->pagesize = 16384;
 				break;
 			case 3:
 				machdep->pagesize = 65536;
@@ -393,6 +393,26 @@ arm64_init(int when)
 				error(FATAL, "cannot malloc ptbl space.");
 			break;
 
+		case 16384:
+			if (machdep->machspec->VA_BITS > PGDIR_SHIFT_L3_16K) {
+				machdep->flags |= VM_L3_16K;
+				if (!machdep->ptrs_per_pgd)
+					machdep->ptrs_per_pgd = PTRS_PER_PGD_L3_16K;
+				if ((machdep->pgd =
+				    (char *)malloc(machdep->ptrs_per_pgd * 8)) == NULL)
+					error(FATAL, "cannot malloc pgd space.");
+				if ((machdep->pmd =
+				    (char *)malloc(PTRS_PER_PMD_L3_16K * 8)) == NULL)
+					error(FATAL, "cannot malloc pmd space.");
+				if ((machdep->ptbl =
+				    (char *)malloc(PTRS_PER_PTE_L3_16K * 8)) == NULL)
+					error(FATAL, "cannot malloc ptbl space.");
+			} else {
+				error(FATAL, "we only support 47 bits, 3 level for 16K page now.");
+			}
+			machdep->pud = NULL;  /* not used */
+			break;
+
 		case 65536:
 			if (kernel_symbol_exists("idmap_ptrs_per_pgd") &&
 			    readmem(symbol_value("idmap_ptrs_per_pgd"), KVADDR,
@@ -1029,6 +1049,8 @@ arm64_dump_machdep_table(ulong arg)
 		fprintf(fp, "%sVM_L2_64K", others++ ? "|" : "");
 	if (machdep->flags & VM_L3_64K)
 		fprintf(fp, "%sVM_L3_64K", others++ ? "|" : "");
+	if (machdep->flags & VM_L3_16K)
+		fprintf(fp, "%sVM_L3_16K", others++ ? "|" : "");
 	if (machdep->flags & VM_L3_4K)
 		fprintf(fp, "%sVM_L3_4K", others++ ? "|" : "");
 	if (machdep->flags & VM_L4_4K)
@@ -1076,6 +1098,8 @@ arm64_dump_machdep_table(ulong arg)
 		"arm64_vtop_3level_4k" :
 		machdep->flags & VM_L4_4K ?
 		"arm64_vtop_4level_4k" :
+		machdep->flags & VM_L3_16K ?
+		"arm64_vtop_3level_16k" :
 		machdep->flags & VM_L3_64K ?
 		"arm64_vtop_3level_64k" : "arm64_vtop_2level_64k");
 	fprintf(fp, "               kvtop: arm64_kvtop()->%s()\n",
@@ -1083,6 +1107,8 @@ arm64_dump_machdep_table(ulong arg)
 		"arm64_vtop_3level_4k" :
 		machdep->flags & VM_L4_4K ?
 		"arm64_vtop_4level_4k" :
+		machdep->flags & VM_L3_16K ?
+		"arm64_vtop_3level_16k" :
 		machdep->flags & VM_L3_64K ?
 		"arm64_vtop_3level_64k" : "arm64_vtop_2level_64k");
 	fprintf(fp, "        get_task_pgd: arm64_get_task_pgd()\n");
@@ -1118,6 +1144,7 @@ arm64_dump_machdep_table(ulong arg)
 	fprintf(fp, "       last_pgd_read: %lx\n", machdep->last_pgd_read);
 	fprintf(fp, "       last_pud_read: ");
 	if ((PAGESIZE() == 65536) ||
+		(PAGESIZE() == 16384) ||
 	    ((PAGESIZE() == 4096) && !(machdep->flags & VM_L4_4K)))
 		fprintf(fp, "(not used)\n");
 	else
@@ -1772,7 +1799,7 @@ arm64_kvtop(struct task_context *tc, ulong kvaddr, physaddr_t *paddr, int verbos
 	kernel_pgd = vt->kernel_pgd[0];
 	*paddr = 0;
 
-	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K))
+	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K|VM_L3_16K))
 	{
 	case VM_L2_64K:
 		return arm64_vtop_2level_64k(kernel_pgd, kvaddr, paddr, verbose);
@@ -1782,6 +1809,8 @@ arm64_kvtop(struct task_context *tc, ulong kvaddr, physaddr_t *paddr, int verbos
 		return arm64_vtop_3level_4k(kernel_pgd, kvaddr, paddr, verbose);
 	case VM_L4_4K:
 		return arm64_vtop_4level_4k(kernel_pgd, kvaddr, paddr, verbose);
+	case VM_L3_16K:
+		return arm64_vtop_3level_16k(kernel_pgd, kvaddr, paddr, verbose);
 	default:
 		return FALSE;
 	}
@@ -1797,7 +1826,7 @@ arm64_uvtop(struct task_context *tc, ulong uvaddr, physaddr_t *paddr, int verbos
 
 	*paddr = 0;
 
-	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K))
+	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K|VM_L3_16K))
 	{
 	case VM_L2_64K:
 		return arm64_vtop_2level_64k(user_pgd, uvaddr, paddr, verbose);
@@ -1807,6 +1836,8 @@ arm64_uvtop(struct task_context *tc, ulong uvaddr, physaddr_t *paddr, int verbos
 		return arm64_vtop_3level_4k(user_pgd, uvaddr, paddr, verbose);
 	case VM_L4_4K:
 		return arm64_vtop_4level_4k(user_pgd, uvaddr, paddr, verbose);
+	case VM_L3_16K:
+		return arm64_vtop_3level_16k(user_pgd, uvaddr, paddr, verbose);
 	default:
 		return FALSE;
 	}
@@ -1823,6 +1854,7 @@ arm64_uvtop(struct task_context *tc, ulong uvaddr, physaddr_t *paddr, int verbos
 #define PMD_TYPE_SECT   1
 #define PMD_TYPE_TABLE  2
 #define SECTION_PAGE_MASK_2MB    ((long)(~((MEGABYTES(2))-1)))
+#define SECTION_PAGE_MASK_32MB  ((long)(~((MEGABYTES(32))-1)))
 #define SECTION_PAGE_MASK_512MB  ((long)(~((MEGABYTES(512))-1)))
 #define SECTION_PAGE_MASK_1GB    ((long)(~((GIGABYTES(1))-1)))
 
@@ -1965,6 +1997,80 @@ no_page:
 	return FALSE;
 }
 
+static int
+arm64_vtop_3level_16k(ulong pgd, ulong vaddr, physaddr_t *paddr, int verbose)
+{
+	ulong *pgd_base, *pgd_ptr, pgd_val;
+	ulong *pmd_base, *pmd_ptr, pmd_val;
+	ulong *pte_base, *pte_ptr, pte_val;
+
+	if (verbose)
+		fprintf(fp, "PAGE DIRECTORY: %lx\n", pgd);
+
+	pgd_base = (ulong *)pgd;
+	FILL_PGD(pgd_base, KVADDR, machdep->ptrs_per_pgd * sizeof(ulong));
+	pgd_ptr = pgd_base + (((vaddr) >> PGDIR_SHIFT_L3_16K) & (machdep->ptrs_per_pgd - 1));
+	pgd_val = ULONG(machdep->pgd + PGDIR_OFFSET_L3_16K(pgd_ptr));
+	if (verbose)
+		fprintf(fp, "   PGD: %lx => %lx\n", (ulong)pgd_ptr, pgd_val);
+	if (!pgd_val)
+		goto no_page;
+
+	/*
+	 * #define __PAGETABLE_PUD_FOLDED
+	 */
+
+	pmd_base = (ulong *)PTOV(PTE_TO_PHYS(pgd_val));
+	FILL_PMD(pmd_base, KVADDR, PTRS_PER_PMD_L3_16K * sizeof(ulong));
+	pmd_ptr = pmd_base + (((vaddr) >> PMD_SHIFT_L3_16K) & (PTRS_PER_PMD_L3_16K - 1));
+	pmd_val = ULONG(machdep->pmd + PAGEOFFSET(pmd_ptr));
+	if (verbose)
+		fprintf(fp, "   PMD: %lx => %lx\n", (ulong)pmd_ptr, pmd_val);
+	if (!pmd_val)
+		goto no_page;
+
+	if ((pmd_val & PMD_TYPE_MASK) == PMD_TYPE_SECT) {
+		ulong sectionbase = PTE_TO_PHYS(pmd_val) & SECTION_PAGE_MASK_32MB;
+		if (verbose) {
+			fprintf(fp, "  PAGE: %lx  (32MB%s)\n\n", sectionbase,
+				IS_ZEROPAGE(sectionbase) ? ", ZERO PAGE" : "");
+			arm64_translate_pte(pmd_val, 0, 0);
+		}
+		*paddr = sectionbase + (vaddr & ~SECTION_PAGE_MASK_32MB);
+		return TRUE;
+	}
+
+	pte_base = (ulong *)PTOV(PTE_TO_PHYS(pmd_val));
+	FILL_PTBL(pte_base, KVADDR, PTRS_PER_PTE_L3_16K * sizeof(ulong));
+	pte_ptr = pte_base + (((vaddr) >> machdep->pageshift) & (PTRS_PER_PTE_L3_16K - 1));
+	pte_val = ULONG(machdep->ptbl + PAGEOFFSET(pte_ptr));
+	if (verbose)
+		fprintf(fp, "   PTE: %lx => %lx\n", (ulong)pte_ptr, pte_val);
+	if (!pte_val)
+		goto no_page;
+
+	if (pte_val & PTE_VALID) {
+		*paddr = PTE_TO_PHYS(pte_val) + PAGEOFFSET(vaddr);
+		if (verbose) {
+			fprintf(fp, "  PAGE: %lx  %s\n\n", PAGEBASE(*paddr),
+				IS_ZEROPAGE(PAGEBASE(*paddr)) ? "(ZERO PAGE)" : "");
+			arm64_translate_pte(pte_val, 0, 0);
+		}
+	} else {
+		if (IS_UVADDR(vaddr, NULL))
+			*paddr = pte_val;
+		if (verbose) {
+			fprintf(fp, "\n");
+			arm64_translate_pte(pte_val, 0, 0);
+		}
+		goto no_page;
+	}
+
+	return TRUE;
+no_page:
+	return FALSE;
+}
+
 static int 
 arm64_vtop_3level_4k(ulong pgd, ulong vaddr, physaddr_t *paddr, int verbose)
 {
diff --git a/defs.h b/defs.h
index 49e6923..1b7649d 100644
--- a/defs.h
+++ b/defs.h
@@ -3302,6 +3302,21 @@ typedef signed int s32;
 #define PGDIR_MASK_48VA      (~(PGDIR_SIZE_48VA - 1))
 #define PGDIR_OFFSET_48VA(X) (((ulong)(X)) & (PGDIR_SIZE_48VA - 1))
 
+/*
+ * 3-levels / 16K pages
+ * 47-bit VA
+ */
+#define PTRS_PER_PGD_L3_16K   ((1UL) << (47 - 36))
+#define PTRS_PER_PMD_L3_16K   (2048)
+#define PTRS_PER_PTE_L3_16K   (2048)
+#define PGDIR_SHIFT_L3_16K    (36)
+#define PGDIR_SIZE_L3_16K     ((1UL) << PGDIR_SHIFT_L3_16K)
+#define PGDIR_MASK_L3_16K     (~(PGDIR_SIZE_L3_16K-1))
+#define PMD_SHIFT_L3_16K      (25)
+#define PMD_SIZE_L3_16K       (1UL << PMD_SHIFT_L3_16K)
+#define PMD_MASK_L3_16K       (~(PMD_SIZE_L3_16K-1))
+#define PGDIR_OFFSET_L3_16K(X) (((ulong)(X)) & ((machdep->ptrs_per_pgd * 8) - 1))
+
 /*
  * 3-levels / 64K pages
  */
@@ -3367,6 +3382,7 @@ typedef signed int s32;
 #define HAS_PHYSVIRT_OFFSET (0x800)
 #define OVERFLOW_STACKS     (0x1000)
 #define ARM64_MTE     (0x2000)
+#define VM_L3_16K     (0x4000)
 
 /*
  * Get kimage_voffset from /dev/crash
-- 
2.40.1