WSL2-Linux-Kernel/arch/arm/mm
Giulio Benetti 7ae0262748 ARM: 9266/1: mm: fix no-MMU ZERO_PAGE() implementation
[ Upstream commit 340a982825 ]

Actually in no-MMU SoCs(i.e. i.MXRT) ZERO_PAGE(vaddr) expands to
```
virt_to_page(0)
```
that in order expands to:
```
pfn_to_page(virt_to_pfn(0))
```
and then virt_to_pfn(0) to:
```
        ((((unsigned long)(0) - PAGE_OFFSET) >> PAGE_SHIFT) +
         PHYS_PFN_OFFSET)
```
where PAGE_OFFSET and PHYS_PFN_OFFSET are the DRAM offset(0x80000000) and
PAGE_SHIFT is 12. This way we obtain 16MB(0x01000000) summed to the base of
DRAM(0x80000000).
When ZERO_PAGE(0) is then used, for example in bio_add_page(), the page
gets an address that is out of DRAM bounds.
So instead of using fake virtual page 0 let's allocate a dedicated
zero_page during paging_init() and assign it to a global 'struct page *
empty_zero_page' the same way mmu.c does and it's the same approach used
in m68k with commit dc068f4621 as discussed here[0]. Then let's move
ZERO_PAGE() definition to the top of pgtable.h to be in common between
mmu.c and nommu.c.

[0]: https://lore.kernel.org/linux-m68k/2a462b23-5b8e-bbf4-ec7d-778434a3b9d7@google.com/T/#m1266ceb63
ad140743174d6b3070364d3c9a5179b

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14 11:37:15 +01:00
..
Kconfig ARM: Spectre-BHB workaround 2022-03-11 12:22:32 +01:00
Makefile ARM updates for 5.11: 2020-12-22 13:34:27 -08:00
abort-ev4.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-ev4t.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-ev5t.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-ev5tj.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-ev6.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-ev7.S ARM: 9091/1: Revert "mm: qsd8x50: Fix incorrect permission faults" 2021-06-13 18:16:43 +01:00
abort-lv4t.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-macro.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
abort-nommu.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
alignment.c ARM: 9214/1: alignment: advance IT state after emulating Thumb instruction 2022-07-21 21:24:12 +02:00
cache-b15-rac.c ARM: mm: Remove virtual address print from B15 RAC driver 2020-05-06 11:12:12 -07:00
cache-fa.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-feroceon-l2.c ARM: 8416/1: Feroceon: use of_iomap() to map register base 2015-08-18 14:00:30 +01:00
cache-l2x0-pmu.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
cache-l2x0.c ARM: 9007/1: l2c: fix prefetch bits init in L2X0_AUX_CTRL using DT values 2020-09-15 14:35:53 +01:00
cache-nop.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-tauros2.c ARM: l2c: tauros2: use descriptive definitions for register bits 2015-11-26 22:12:26 +00:00
cache-tauros3.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 171 2019-05-30 11:26:39 -07:00
cache-uniphier.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
cache-v4.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-v4wb.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-v4wt.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-v6.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cache-v7.S ARM: 9059/1: cache-v7: get rid of mini-stack 2021-03-09 10:25:18 +00:00
cache-v7m.S sched/rt, ARM: Use CONFIG_PREEMPTION 2019-12-08 14:37:32 +01:00
cache-xsc3l2.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
context.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-fa.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-feroceon.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-v4mc.c mm: move page_mapping_file to pagemap.h 2021-04-30 11:20:37 -07:00
copypage-v4wb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-v4wt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-v6.c mm: move page_mapping_file to pagemap.h 2021-04-30 11:20:37 -07:00
copypage-xsc3.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
copypage-xscale.c mm: move page_mapping_file to pagemap.h 2021-04-30 11:20:37 -07:00
dma-mapping-nommu.c ARM/nommu: use the generic dma-direct code for non-coherent devices 2021-08-18 16:24:10 +02:00
dma-mapping.c ARM/dma-mapping: don't set failed sg dma_address to DMA_MAPPING_ERROR 2021-08-09 17:13:05 +02:00
dma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dump.c ARM: 9244/1: dump: Fix wrong pg_level in walk_pmd() 2022-10-26 12:34:37 +02:00
extable.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fault-armv.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
fault.c mm/arm: use general page fault accounting 2020-08-12 10:58:03 -07:00
fault.h ARM: 8898/1: mm: Don't treat faults reported from cache maintenance as writes 2019-08-23 11:39:34 +01:00
flush.c mm: remove flush_kernel_dcache_page 2021-09-03 09:58:13 -07:00
fsr-2level.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fsr-3level.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hugetlbpage.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
idmap.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
init.c arm: extend pfn_valid to take into account freed memory map alignment 2021-06-30 11:39:00 +03:00
iomap.c ARM: 8923/1: mm: include <asm/vga.h> for vga_base 2019-10-31 16:58:54 +00:00
ioremap.c arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear map 2022-05-18 10:26:56 +02:00
kasan_init.c ARM: 9242/1: kasan: Only map modules if CONFIG_KASAN_VMALLOC=n 2022-10-26 12:35:45 +02:00
l2c-common.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
l2c-l2x0-resume.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm.h mm: pgtable: add shortcuts for accessing kernel PMD and PTE 2020-06-09 09:39:13 -07:00
mmap.c arm: Use the generic devmem_is_allowed() 2020-12-11 12:28:24 -08:00
mmu.c ARM: 9247/1: mm: set readonly for MT_MEMORY_RO with ARM_LPAE 2022-10-26 12:34:37 +02:00
nommu.c ARM: 9266/1: mm: fix no-MMU ZERO_PAGE() implementation 2022-12-14 11:37:15 +01:00
pabort-legacy.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pabort-v6.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pabort-v7.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pageattr.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
pgd.c ARM: 9016/2: Initialize the mapping of KASan shadow memory 2020-10-27 12:11:10 +00:00
physaddr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pmsa-v7.c ARM: 9069/1: NOMMU: Fix conversion for_each_membock() to for_each_mem_range() 2021-03-25 10:25:20 +00:00
pmsa-v8.c ARM: 9069/1: NOMMU: Fix conversion for_each_membock() to for_each_mem_range() 2021-03-25 10:25:20 +00:00
proc-arm7tdmi.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm9tdmi.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm720.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm740.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm920.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm922.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm925.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm926.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm940.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm946.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm1020.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm1020e.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm1022.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-arm1026.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-fa526.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-feroceon.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-macros.S ARM: 9133/1: mm: proc-macros: ensure *_tlb_fns are 4B aligned 2021-10-19 10:37:35 +01:00
proc-mohawk.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-sa110.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-sa1100.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-syms.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
proc-v6.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-v7-2level.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
proc-v7-3level.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
proc-v7-bugs.c ARM: 9209/1: Spectre-BHB: avoid pr_info() every time a CPU comes out of idle 2022-07-21 21:24:16 +02:00
proc-v7.S ARM: 9059/1: cache-v7: get rid of mini-stack 2021-03-09 10:25:18 +00:00
proc-v7m.S ARM: 8933/1: replace Sun/Solaris style flag on section directive 2019-11-15 22:21:19 +00:00
proc-xsc3.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
proc-xscale.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
ptdump_debugfs.c ARM: 9074/1: ptdump: convert to DEFINE_SHOW_ATTRIBUTE 2021-04-18 19:15:13 +01:00
pv-fixup-asm.S ARM: 9104/2: Fix Keystone 2 kernel mapping regression 2021-08-10 12:17:25 +01:00
tcm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
tlb-fa.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
tlb-v4.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
tlb-v4wb.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
tlb-v4wbi.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
tlb-v6.S mm: update legacy flush_tlb_* to use vma 2021-06-29 10:53:52 -07:00
tlb-v7.S mm: update legacy flush_tlb_* to use vma 2021-06-29 10:53:52 -07:00