I've just discovered that I've booted qemu-sparc with the wrong kernel and
this patch crashes miserably :(
The better version that does allow qemu-sparc to boot with folded page
tables is below:
>From a90e1d157b7f8786a4276ffc8553f2167c8bc0e7 Mon Sep 17 00:00:00 2001
From: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Date: Tue, 1 Oct 2019 17:14:38 +0300
Subject: [PATCH v2] sparc32: use pgtable-nopud instead of 4level-fixup
32-bit version of sparc has three-level page tables and can use
pgtable-nopud and folding of the upper layers.
Replace usage of include/asm-generic/4level-fixup.h with
include/asm-generic/pgtable-nopud.h and adjust page table manipulation
macros and functions accordingly.
Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
---
arch/sparc/include/asm/pgalloc_32.h | 6 ++---
arch/sparc/include/asm/pgtable_32.h | 28 ++++++++++----------
arch/sparc/mm/fault_32.c | 11 ++++++--
arch/sparc/mm/highmem.c | 6 ++++-
arch/sparc/mm/io-unit.c | 6 ++++-
arch/sparc/mm/iommu.c | 6 ++++-
arch/sparc/mm/srmmu.c | 51 +++++++++++++++++++++++++++++--------
7 files changed, 81 insertions(+), 33 deletions(-)
diff --git a/arch/sparc/include/asm/pgalloc_32.h b/arch/sparc/include/asm/pgalloc_32.h
index 10538a4..eae0c92 100644
--- a/arch/sparc/include/asm/pgalloc_32.h
+++ b/arch/sparc/include/asm/pgalloc_32.h
@@ -26,14 +26,14 @@ static inline void free_pgd_fast(pgd_t *pgd)
#define pgd_free(mm, pgd) free_pgd_fast(pgd)
#define pgd_alloc(mm) get_pgd_fast()
-static inline void pgd_set(pgd_t * pgdp, pmd_t * pmdp)
+static inline void pud_set(pud_t * pudp, pmd_t * pmdp)
{
unsigned long pa = __nocache_pa(pmdp);
- set_pte((pte_t *)pgdp, __pte((SRMMU_ET_PTD | (pa >> 4))));
+ set_pte((pte_t *)pudp, __pte((SRMMU_ET_PTD | (pa >> 4))));
}
-#define pgd_populate(MM, PGD, PMD) pgd_set(PGD, PMD)
+#define pud_populate(MM, PGD, PMD) pud_set(PGD, PMD)
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm,
unsigned long address)
diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
index 31da448..6d6f44c 100644
--- a/arch/sparc/include/asm/pgtable_32.h
+++ b/arch/sparc/include/asm/pgtable_32.h
@@ -12,7 +12,7 @@
#include <linux/const.h>
#ifndef __ASSEMBLY__
-#include <asm-generic/4level-fixup.h>
+#include <asm-generic/pgtable-nopud.h>
#include <linux/spinlock.h>
#include <linux/mm_types.h>
@@ -132,12 +132,12 @@ static inline struct page *pmd_page(pmd_t pmd)
return pfn_to_page((pmd_val(pmd) & SRMMU_PTD_PMASK) >> (PAGE_SHIFT-4));
}
-static inline unsigned long pgd_page_vaddr(pgd_t pgd)
+static inline unsigned long pud_page_vaddr(pud_t pud)
{
- if (srmmu_device_memory(pgd_val(pgd))) {
+ if (srmmu_device_memory(pud_val(pud))) {
return ~0;
} else {
- unsigned long v = pgd_val(pgd) & SRMMU_PTD_PMASK;
+ unsigned long v = pud_val(pud) & SRMMU_PTD_PMASK;
return (unsigned long)__nocache_va(v << 4);
}
}
@@ -184,24 +184,24 @@ static inline void pmd_clear(pmd_t *pmdp)
set_pte((pte_t *)&pmdp->pmdv[i], __pte(0));
}
-static inline int pgd_none(pgd_t pgd)
+static inline int pud_none(pud_t pud)
{
- return !(pgd_val(pgd) & 0xFFFFFFF);
+ return !(pud_val(pud) & 0xFFFFFFF);
}
-static inline int pgd_bad(pgd_t pgd)
+static inline int pud_bad(pud_t pud)
{
- return (pgd_val(pgd) & SRMMU_ET_MASK) != SRMMU_ET_PTD;
+ return (pud_val(pud) & SRMMU_ET_MASK) != SRMMU_ET_PTD;
}
-static inline int pgd_present(pgd_t pgd)
+static inline int pud_present(pud_t pud)
{
- return ((pgd_val(pgd) & SRMMU_ET_MASK) == SRMMU_ET_PTD);
+ return ((pud_val(pud) & SRMMU_ET_MASK) == SRMMU_ET_PTD);
}
-static inline void pgd_clear(pgd_t *pgdp)
+static inline void pud_clear(pud_t *pudp)
{
- set_pte((pte_t *)pgdp, __pte(0));
+ set_pte((pte_t *)pudp, __pte(0));
}
/*
@@ -319,9 +319,9 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
/* Find an entry in the second-level page table.. */
-static inline pmd_t *pmd_offset(pgd_t * dir, unsigned long address)
+static inline pmd_t *pmd_offset(pud_t * dir, unsigned long address)
{
- return (pmd_t *) pgd_page_vaddr(*dir) +
+ return (pmd_t *) pud_page_vaddr(*dir) +
((address >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
}
diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index 8d69de1..89976c9 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -351,6 +351,8 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
*/
int offset = pgd_index(address);
pgd_t *pgd, *pgd_k;
+ p4d_t *p4d, *p4d_k;
+ pud_t *pud, *pud_k;
pmd_t *pmd, *pmd_k;
pgd = tsk->active_mm->pgd + offset;
@@ -363,8 +365,13 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
return;
}
- pmd = pmd_offset(pgd, address);
- pmd_k = pmd_offset(pgd_k, address);
+ p4d = p4d_offset(pgd, address);
+ pud = pud_offset(p4d, address);
+ pmd = pmd_offset(pud, address);
+
+ p4d_k = p4d_offset(pgd_k, address);
+ pud_k = pud_offset(p4d_k, address);
+ pmd_k = pmd_offset(pud_k, address);
if (pmd_present(*pmd) || !pmd_present(*pmd_k))
goto bad_area_nosemaphore;
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
index 86bc2a5..d4a80ad 100644
--- a/arch/sparc/mm/highmem.c
+++ b/arch/sparc/mm/highmem.c
@@ -39,10 +39,14 @@ static pte_t *kmap_pte;
void __init kmap_init(void)
{
unsigned long address;
+ p4d_t *p4d;
+ pud_t *pud;
pmd_t *dir;
address = __fix_to_virt(FIX_KMAP_BEGIN);
- dir = pmd_offset(pgd_offset_k(address), address);
+ p4d = p4d_offset(pgd_offset_k(address), address);
+ pud = pud_offset(p4d, address);
+ dir = pmd_offset(pud, address);
/* cache the first kmap pte */
kmap_pte = pte_offset_kernel(dir, address);
diff --git a/arch/sparc/mm/io-unit.c b/arch/sparc/mm/io-unit.c
index f770ee7..33a0fac 100644
--- a/arch/sparc/mm/io-unit.c
+++ b/arch/sparc/mm/io-unit.c
@@ -239,12 +239,16 @@ static void *iounit_alloc(struct device *dev, size_t len,
page = va;
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
long i;
pgdp = pgd_offset(&init_mm, addr);
- pmdp = pmd_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ pudp = pud_offset(p4dp, addr);
+ pmdp = pmd_offset(pudp, addr);
ptep = pte_offset_map(pmdp, addr);
set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
diff --git a/arch/sparc/mm/iommu.c b/arch/sparc/mm/iommu.c
index 71ac353..4d3c699 100644
--- a/arch/sparc/mm/iommu.c
+++ b/arch/sparc/mm/iommu.c
@@ -343,6 +343,8 @@ static void *sbus_iommu_alloc(struct device *dev, size_t len,
page = va;
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
@@ -354,7 +356,9 @@ static void *sbus_iommu_alloc(struct device *dev, size_t len,
__flush_page_to_ram(page);
pgdp = pgd_offset(&init_mm, addr);
- pmdp = pmd_offset(pgdp, addr);
+ p4dp = p4d_offset(pgdp, addr);
+ pudp = pud_offset(p4dp, addr);
+ pmdp = pmd_offset(pudp, addr);
ptep = pte_offset_map(pmdp, addr);
set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index cc3ad64..f56c3c9 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -296,6 +296,8 @@ static void __init srmmu_nocache_init(void)
void *srmmu_nocache_bitmap;
unsigned int bitmap_bits;
pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long paddr, vaddr;
@@ -329,6 +331,8 @@ static void __init srmmu_nocache_init(void)
while (vaddr < srmmu_nocache_end) {
pgd = pgd_offset_k(vaddr);
+ p4d = p4d_offset(__nocache_fix(pgd), vaddr);
+ pud = pud_offset(__nocache_fix(p4d), vaddr);
pmd = pmd_offset(__nocache_fix(pgd), vaddr);
pte = pte_offset_kernel(__nocache_fix(pmd), vaddr);
@@ -516,13 +520,17 @@ static inline void srmmu_mapioaddr(unsigned long physaddr,
unsigned long virt_addr, int bus_type)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
unsigned long tmp;
physaddr &= PAGE_MASK;
pgdp = pgd_offset_k(virt_addr);
- pmdp = pmd_offset(pgdp, virt_addr);
+ p4dp = p4d_offset(pgdp, virt_addr);
+ pudp = pud_offset(p4dp, virt_addr);
+ pmdp = pmd_offset(pudp, virt_addr);
ptep = pte_offset_kernel(pmdp, virt_addr);
tmp = (physaddr >> 4) | SRMMU_ET_PTE;
@@ -551,11 +559,16 @@ void srmmu_mapiorange(unsigned int bus, unsigned long xpa,
static inline void srmmu_unmapioaddr(unsigned long virt_addr)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
+
pgdp = pgd_offset_k(virt_addr);
- pmdp = pmd_offset(pgdp, virt_addr);
+ p4dp = p4d_offset(pgdp, virt_addr);
+ pudp = pud_offset(p4dp, virt_addr);
+ pmdp = pmd_offset(pudp, virt_addr);
ptep = pte_offset_kernel(pmdp, virt_addr);
/* No need to flush uncacheable page. */
@@ -693,20 +706,24 @@ static void __init srmmu_early_allocate_ptable_skeleton(unsigned long start,
unsigned long end)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
while (start < end) {
pgdp = pgd_offset_k(start);
- if (pgd_none(*(pgd_t *)__nocache_fix(pgdp))) {
+ p4dp = p4d_offset(pgdp, start);
+ pudp = pud_offset(p4dp, start);
+ if (pud_none(*(pud_t *)__nocache_fix(pudp))) {
pmdp = __srmmu_get_nocache(
SRMMU_PMD_TABLE_SIZE, SRMMU_PMD_TABLE_SIZE);
if (pmdp == NULL)
early_pgtable_allocfail("pmd");
memset(__nocache_fix(pmdp), 0, SRMMU_PMD_TABLE_SIZE);
- pgd_set(__nocache_fix(pgdp), pmdp);
+ pud_set(__nocache_fix(pudp), pmdp);
}
- pmdp = pmd_offset(__nocache_fix(pgdp), start);
+ pmdp = pmd_offset(__nocache_fix(pudp), start);
if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) {
ptep = __srmmu_get_nocache(PTE_SIZE, PTE_SIZE);
if (ptep == NULL)
@@ -724,19 +741,23 @@ static void __init srmmu_allocate_ptable_skeleton(unsigned long start,
unsigned long end)
{
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
while (start < end) {
pgdp = pgd_offset_k(start);
- if (pgd_none(*pgdp)) {
+ p4dp = p4d_offset(pgdp, start);
+ pudp = pud_offset(p4dp, start);
+ if (pud_none(*pudp)) {
pmdp = __srmmu_get_nocache(SRMMU_PMD_TABLE_SIZE, SRMMU_PMD_TABLE_SIZE);
if (pmdp == NULL)
early_pgtable_allocfail("pmd");
memset(pmdp, 0, SRMMU_PMD_TABLE_SIZE);
- pgd_set(pgdp, pmdp);
+ pud_set((pud_t *)pgdp, pmdp);
}
- pmdp = pmd_offset(pgdp, start);
+ pmdp = pmd_offset(pudp, start);
if (srmmu_pmd_none(*pmdp)) {
ptep = __srmmu_get_nocache(PTE_SIZE,
PTE_SIZE);
@@ -779,6 +800,8 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start,
unsigned long probed;
unsigned long addr;
pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
int what; /* 0 = normal-pte, 1 = pmd-level pte, 2 = pgd-level pte */
@@ -810,18 +833,20 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start,
}
pgdp = pgd_offset_k(start);
+ p4dp = p4d_offset(pgdp, start);
+ pudp = pud_offset(p4dp, start);
if (what == 2) {
*(pgd_t *)__nocache_fix(pgdp) = __pgd(probed);
start += SRMMU_PGDIR_SIZE;
continue;
}
- if (pgd_none(*(pgd_t *)__nocache_fix(pgdp))) {
+ if (pud_none(*(pud_t *)__nocache_fix(pudp))) {
pmdp = __srmmu_get_nocache(SRMMU_PMD_TABLE_SIZE,
SRMMU_PMD_TABLE_SIZE);
if (pmdp == NULL)
early_pgtable_allocfail("pmd");
memset(__nocache_fix(pmdp), 0, SRMMU_PMD_TABLE_SIZE);
- pgd_set(__nocache_fix(pgdp), pmdp);
+ pud_set(__nocache_fix(pudp), pmdp);
}
pmdp = pmd_offset(__nocache_fix(pgdp), start);
if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) {
@@ -906,6 +931,8 @@ void __init srmmu_paging_init(void)
phandle cpunode;
char node_str[128];
pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long pages_avail;
@@ -967,7 +994,9 @@ void __init srmmu_paging_init(void)
srmmu_allocate_ptable_skeleton(PKMAP_BASE, PKMAP_END);
pgd = pgd_offset_k(PKMAP_BASE);
- pmd = pmd_offset(pgd, PKMAP_BASE);
+ p4d = p4d_offset(pgd, PKMAP_BASE);
+ pud = pud_offset(p4d, PKMAP_BASE);
+ pmd = pmd_offset(pud, PKMAP_BASE);
pte = pte_offset_kernel(pmd, PKMAP_BASE);
pkmap_page_table = pte;
--
2.7.4
