LoongArch: Make {virt, phys, page, pfn} translation work with KFENCE

KFENCE changes virt_to_page() to be able to translate tlb mapped virtual
addresses, but forget to change virt_to_phys()/phys_to_virt() and other
translation functions as well. This patch fix it, otherwise some drivers
(such as nvme and virtio-blk) cannot work with KFENCE.

All {virt, phys, page, pfn} translation functions are updated:
1, virt_to_pfn()/pfn_to_virt();
2, virt_to_page()/page_to_virt();
3, virt_to_phys()/phys_to_virt().

DMW/TLB mapped addresses are distinguished by comparing the vaddress
with vm_map_base in virt_to_xyz(), and we define WANT_PAGE_VIRTUAL in
the KFENCE case for the reverse translations, xyz_to_virt().

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

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>

arch: consolidate existing CONFIG_PAGE_SIZE_*KB definitions

These four architectures define the same Kconfig symbols for configuring
the page size. Move the logic into a common place where it can be shared
with all other architectures.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

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: Add support to clone a time namespace

We can see that "Time namespaces are not supported" on LoongArch:

(1) clone3 test
# cd tools/testing/selftests/clone3 && make && ./clone3
...
# Time namespaces are not supported
ok 18 # SKIP Skipping clone3() with CLONE_NEWTIME
# Totals: pass:17 fail:0 xfail:0 xpass:0 skip:1 error:0

(2) timens test
# cd tools/testing/selftests/timens && make && ./timens
...
1..0 # SKIP Time namespaces are not supported

On LoongArch the current kernel does not support CONFIG_TIME_NS which
depends on GENERIC_VDSO_TIME_NS, select GENERIC_VDSO_TIME_NS to enable
CONFIG_TIME_NS to build kernel/time/namespace.c.

Additionally, it needs to define some arch-dependent functions for the
timens, such as __arch_get_timens_vdso_data(), arch_get_vdso_data() and
vdso_join_timens().

At the same time, modify the layout of vvar to use one page size for
generic vdso data, expand another page size for timens vdso data and
assign LOONGARCH_VDSO_DATA_SIZE (maybe exceeds a page size if expand in
the future) for loongarch vdso data, at last add the callback function
vvar_fault() and modify stack_top().

With this patch under CONFIG_TIME_NS:

(1) clone3 test
# cd tools/testing/selftests/clone3 && make && ./clone3
...
ok 18 [739] Result (0) matches expectation (0)
# Totals: pass:18 fail:0 xfail:0 xpass:0 skip:0 error:0

(2) timens test
# cd tools/testing/selftests/timens && make && ./timens
...
# Totals: pass:10 fail:0 xfail:0 xpass:0 skip:0 error:0

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

mm, arch: add generic implementation of pfn_valid() for FLATMEM

Every architecture that supports FLATMEM memory model defines its own
version of pfn_valid() that essentially compares a pfn to max_mapnr.

Use mips/powerpc version implemented as static inline as a generic
implementation of pfn_valid() and drop its per-architecture definitions.

[rppt@kernel.org: fix the generic pfn_valid()]
Link: https://lkml.kernel.org/r/Y9lg7R1Yd931C+y5@kernel.org
Link: https://lkml.kernel.org/r/20230129124235.209895-5-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Huacai Chen <chenhuacai@loongson.cn> [LoongArch]
Acked-by: Stafford Horne <shorne@gmail.com> [OpenRISC]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Cc: Brian Cain <bcain@quicinc.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
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: Add PCI controller support

Loongson64 based systems are PC-like systems which use PCI/PCIe as its
I/O bus, This patch adds the PCI host controller support for LoongArch.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Fix build errors for tinyconfig

Building loongarch:tinyconfig fails with the following error.

./arch/loongarch/include/asm/page.h: In function 'pfn_valid':
./arch/loongarch/include/asm/page.h:42:32: error: 'PHYS_OFFSET' undeclared

Add the missing include file and fix succeeding vdso errors.

Fixes: 09cfefb7fa70 ("LoongArch: Add memory management")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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>