LoongArch: Move {dmw,tlb}_virt_to_page() definition to page.h

These two functions are implemented in pgtable.c, and they are needed
only by the virt_to_page() macro in page.h. Having the prototypes in
pgtable.h causes a circular dependency between page.h and pgtable.h,
because the virt_to_page() macro in page.h needs pgtable.h for these
two functions, while pgtable.h needs various definitions from page.h
(e.g. pte_t and pgt_t).

Let's avoid this circular dependency by moving the function prototypes
to page.h.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

mm/mglru: add dummy pmd_dirty()

Add dummy pmd_dirty() for architectures that don't provide it.
This is similar to commit 6617da8fb565 ("mm: add dummy pmd_young()
for architectures not having it").

Link: https://lkml.kernel.org/r/20231227141205.2200125-5-kinseyho@google.com
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312210606.1Etqz3M4-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202312210042.xQEiqlEh-lkp@intel.com/
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Suggested-by: Yu Zhao <yuzhao@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: Add KASAN (Kernel Address Sanitizer) support

1/8 of kernel addresses reserved for shadow memory. But for LoongArch,
There are a lot of holes between different segments and valid address
space (256T available) is insufficient to map all these segments to kasan
shadow memory with the common formula provided by kasan core, saying
(addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET

So LoongArch has a arch-specific mapping formula, different segments are
mapped individually, and only limited space lengths of these specific
segments are mapped to shadow.

At early boot stage the whole shadow region populated with just one
physical page (kasan_early_shadow_page). Later, this page is reused as
readonly zero shadow for some memory that kasan currently don't track.
After mapping the physical memory, pages for shadow memory are allocated
and mapped.

Functions like memset()/memcpy()/memmove() do a lot of memory accesses.
If bad pointer passed to one of these function it is important to be
caught. Compiler's instrumentation cannot do this since these functions
are written in assembly.

KASan replaces memory functions with manually instrumented variants.
Original functions declared as weak symbols so strong definitions in
mm/kasan/kasan.c could replace them. Original functions have aliases
with '__' prefix in names, so we could call non-instrumented variant
if needed.

Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add KFENCE (Kernel Electric-Fence) support

The LoongArch architecture is quite different from other architectures.
When the allocating of KFENCE itself is done, it is mapped to the direct
mapping configuration window [1] by default on LoongArch. It means that
it is not possible to use the page table mapped mode which required by
the KFENCE system and therefore it should be remapped to the appropriate
region.

This patch adds architecture specific implementation details for KFENCE.
In particular, this implements the required interface in <asm/kfence.h>.

Tested this patch by running the testcases and all passed.

[1] https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#virtual-address-space-and-address-translation-mode

Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: mm: Add page table mapped mode support for virt_to_page()

According to LoongArch documentations, there are two types of address
translation modes: direct mapped address translation mode (DMW mode) and
page table mapped address translation mode (TLB mode).

Currently, virt_to_page() only supports direct mapped mode. This patch
determines which mode is used, and adds corresponding handling functions
for both modes.

For more details on the two modes, see [1].

[1] https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#virtual-address-space-and-address-translation-mode

Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Use static defined zero page rather than allocated

On LoongArch system, there is only one page needed for zero page (no
cache synonyms), and there is no COLOR_ZERO_PAGE, so zero_page_mask is
useless and the macro __HAVE_COLOR_ZERO_PAGE is not necessary.

Like other popular architectures, It is simpler to define the zero page
in kernel BSS code segment rather than dynamically allocate.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: mm: Add p?d_leaf() definitions

When I do LTP test, LTP test case ksm06 caused panic at
break_ksm_pmd_entry
-> pmd_leaf (Huge page table but False)
-> pte_present (panic)

The reason is pmd_leaf() is not defined, So like commit 501b81046701
("mips: mm: add p?d_leaf() definitions") add p?d_leaf() definition for
LoongArch.

Fixes: 09cfefb7fa70 ("LoongArch: Add memory management")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

mm: Rename arch pte_mkwrite()'s to pte_mkwrite_novma()

The x86 Shadow stack feature includes a new type of memory called shadow
stack. This shadow stack memory has some unusual properties, which requires
some core mm changes to function properly.

One of these unusual properties is that shadow stack memory is writable,
but only in limited ways. These limits are applied via a specific PTE
bit combination. Nevertheless, the memory is writable, and core mm code
will need to apply the writable permissions in the typical paths that
call pte_mkwrite(). The goal is to make pte_mkwrite() take a VMA, so
that the x86 implementation of it can know whether to create regular
writable or shadow stack mappings.

But there are a couple of challenges to this. Modifying the signatures of
each arch pte_mkwrite() implementation would be error prone because some
are generated with macros and would need to be re-implemented. Also, some
pte_mkwrite() callers operate on kernel memory without a VMA.

So this can be done in a three step process. First pte_mkwrite() can be
renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite()
added that just calls pte_mkwrite_novma(). Next callers without a VMA can
be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers
can be changed to take/pass a VMA.

Start the process by renaming pte_mkwrite() to pte_mkwrite_novma() and
adding the pte_mkwrite() wrapper in linux/pgtable.h. Apply the same
pattern for pmd_mkwrite(). Since not all archs have a pmd_mkwrite_novma(),
create a new arch config HAS_HUGE_PAGE that can be used to tell if
pmd_mkwrite() should be defined. Otherwise in the !HAS_HUGE_PAGE cases the
compiler would not be able to find pmd_mkwrite_novma().

No functional change.

Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/lkml/CAHk-=wiZjSu7c9sFYZb3q04108stgHff2wfbokGCCgW7riz+8Q@mail.gmail.com/
Link: https://lore.kernel.org/all/20230613001108.3040476-2-rick.p.edgecombe%40intel.com

loongarch: implement the new page table range API

Add update_mmu_cache_range() and change _PFN_SHIFT to PFN_PTE_SHIFT. It
would probably be more efficient to implement __update_tlb() by flushing
the entire folio instead of calling __update_tlb() N times, but I'll leave
that for someone who understands the architecture better.

Link: https://lkml.kernel.org/r/20230802151406.3735276-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: Introduce hardware page table walker

Loongson-3A6000 and newer processors have hardware page table walker
(PTW) support. PTW can handle all fastpaths of TLBI/TLBL/TLBS/TLBM
exceptions by hardware, software only need to handle slowpaths (page
faults).

BTW, PTW doesn't append _PAGE_MODIFIED for page table entries, so we
change pmd_dirty() and pte_dirty() to also check _PAGE_DIRTY for the
"dirty" attribute.

Signed-off-by: Liang Gao <gaoliang@loongson.cn>
Signed-off-by: Jun Yi <yijun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Let pmd_present() return true when splitting pmd

When we split a pmd into ptes, pmd_present() and pmd_trans_huge() should
return true, otherwise it would be treated as a swap pmd.

This is the same as arm64 does in commit b65399f6111b ("arm64/mm: Change
THP helpers to comply with generic MM semantics"), we also add a new bit
named _PAGE_PRESENT_INVALID for LoongArch.

Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

mm: remove __HAVE_ARCH_PTE_SWP_EXCLUSIVE

__HAVE_ARCH_PTE_SWP_EXCLUSIVE is now supported by all architectures that
support swp PTEs, so let's drop it.

Link: https://lkml.kernel.org/r/20230113171026.582290-27-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

loongarch/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE

Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the
type. Generic MM currently only uses 5 bits for the type
(MAX_SWAPFILES_SHIFT), so the stolen bit is effectively unused.

While at it, also mask the type in mk_swap_pte().

Note that this bit does not conflict with swap PMDs and could also be used
in swap PMD context later.

Link: https://lkml.kernel.org/r/20230113171026.582290-9-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: add sparse memory vmemmap support

Add sparse memory vmemmap support for LoongArch. SPARSEMEM_VMEMMAP uses a
virtually mapped memmap to optimise pfn_to_page and page_to_pfn
operations. This is the most efficient option when sufficient kernel
resources are available.

Link: https://lkml.kernel.org/r/20221027125253.3458989-3-chenhuacai@loongson.cn
Signed-off-by: Min Zhou <zhoumin@loongson.cn>
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Will Deacon <will@kernel.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

MIPS&LoongArch&NIOS2: adjust prototypes of p?d_init()

Patch series "mm/sparse-vmemmap: Generalise helpers and enable for
LoongArch", v14.

This series is in order to enable sparse-vmemmap for LoongArch. But
LoongArch cannot use generic helpers directly because MIPS&LoongArch need
to call pgd_init()/pud_init()/pmd_init() when populating page tables. So
we adjust the prototypes of p?d_init() to make generic helpers can call
them, then enable sparse-vmemmap with generic helpers, and to be further,
generalise vmemmap_populate_hugepages() for ARM64, X86 and LoongArch.


This patch (of 4):

We are preparing to add sparse vmemmap support to LoongArch. MIPS and
LoongArch need to call pgd_init()/pud_init()/pmd_init() when populating
page tables, so adjust their prototypes to make generic helpers can call
them.

NIOS2 declares pmd_init() but doesn't use, just remove it to avoid build
errors.

Link: https://lkml.kernel.org/r/20221027125253.3458989-1-chenhuacai@loongson.cn
Link: https://lkml.kernel.org/r/20221027125253.3458989-2-chenhuacai@loongson.cn
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Will Deacon <will@kernel.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Min Zhou <zhoumin@loongson.cn>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: remove kern_addr_valid() completely

Most architectures (except arm64/x86/sparc) simply return 1 for
kern_addr_valid(), which is only used in read_kcore(), and it calls
copy_from_kernel_nofault() which could check whether the address is a
valid kernel address. So as there is no need for kern_addr_valid(), let's
remove it.

Link: https://lkml.kernel.org/r/20221018074014.185687-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Heiko Carstens <hca@linux.ibm.com> [s390]
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Helge Deller <deller@gmx.de> [parisc]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: <aou@eecs.berkeley.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: add dummy pmd_young() for architectures not having it

In order to avoid #ifdeffery add a dummy pmd_young() implementation as a
fallback. This is required for the later patch "mm: introduce
arch_has_hw_nonleaf_pmd_young()".

Link: https://lkml.kernel.org/r/fd3ac3cd-7349-6bbd-890a-71a9454ca0b3@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite()

Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite().
Otherwise, _PAGE_DIRTY silences the TLB modify exception and make us
have no chance to mark a pmd/pte dirty (_PAGE_MODIFIED) for software.

Reviewed-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()

Now {pmd,pte}_mkdirty() set _PAGE_DIRTY bit unconditionally, this causes
random segmentation fault after commit 0ccf7f168e17bb7e ("mm/thp: carry
over dirty bit when thp splits on pmd").

The reason is: when fork(), parent process use pmd_wrprotect() to clear
huge page's _PAGE_WRITE and _PAGE_DIRTY (for COW); then pte_mkdirty() set
_PAGE_DIRTY as well as _PAGE_MODIFIED while splitting dirty huge pages;
once _PAGE_DIRTY is set, there will be no tlb modify exception so the COW
machanism fails; and at last memory corruption occurred between parent
and child processes.

So, we should set _PAGE_DIRTY only when _PAGE_WRITE is set in {pmd,pte}_
mkdirty().

Cc: stable@vger.kernel.org
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: update local TLB if PTE entry exists

Currently, the implementation of update_mmu_tlb() is empty if
__HAVE_ARCH_UPDATE_MMU_TLB is not defined. Then if two threads
concurrently fault at the same page, the second thread that did not win
the race will give up and do nothing. In the LoongArch architecture, this
second thread will trigger another fault, and only updates its local TLB.

Instead of triggering another fault, it's better to implement
update_mmu_tlb() to directly update the local TLB of the second thread.
Just do it.

Link: https://lkml.kernel.org/r/20220929112318.32393-3-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Suggested-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: Cleanup headers to avoid circular dependency

When enable GENERIC_IOREMAP, there will be circular dependency to cause
build errors. The root cause is that pgtable.h shouldn't include io.h
but pgtable.h need some macros defined in io.h. So cleanup those macros
and remove the unnecessary inclusions, as other architectures do.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

loongarch: drop definition of PGD_ORDER

This is the order of the page table allocation, not the order of a PGD.
Since its always hardwired to 0, simply drop it.

[rppt@linux.ibm.com: drop extra BLANK() line in arch/loongarch/kernel/asm-offsets.c]
Link: https://lkml.kernel.org/r/20220705154708.181258-13-rppt@kernel.org
Link: https://lkml.kernel.org/r/20220703141203.147893-13-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Huacai Chen <chenhuacai@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Xuerui Wang <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

loongarch: drop definition of PUD_ORDER

This is the order of the page table allocation, not the order of a PUD.
Since its always hardwired to 0, simply drop it.

Link: https://lkml.kernel.org/r/20220703141203.147893-12-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Xuerui Wang <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

loongarch: drop definition of PMD_ORDER

This is the order of the page table allocation, not the order of a PMD.
Since its always hardwired to 0, simply drop it.

Link: https://lkml.kernel.org/r/20220703141203.147893-11-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Xuerui Wang <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

loongarch: drop definition of PTE_ORDER

This is the order of the page table allocation, not the order of a PTE.
Since its always hardwired to 0, simply drop it.

Link: https://lkml.kernel.org/r/20220703141203.147893-10-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Xuerui Wang <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

LoongArch: Fix the !THP build

Fix the !THP build by making pmd_pfn() available in all configurations.
Because pmd_pfn() is used in mm/page_vma_mapped.c whether or not THP is
configured.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add Non-Uniform Memory Access (NUMA) support

Add Non-Uniform Memory Access (NUMA) support for LoongArch. LoongArch
has 48-bit physical address, but the HyperTransport I/O bus only support
40-bit address, so we need a custom phys_to_dma() and dma_to_phys() to
extract the 4-bit node id (bit 44~47) from Loongson-3's 48-bit physical
address space and embed it into 40-bit. In the 40-bit dma address, node
id offset can be read from the LS7A_DMA_CFG register.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add multi-processor (SMP) support

LoongArch-based procesors have 4, 8 or 16 cores per package. This patch
adds multi-processor (SMP) support for LoongArch.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add memory management

Add memory management support for LoongArch, including: cache and tlb
management, page fault handling and ioremap/mmap support.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>