diff mbox series

[v3,10/52] xen/arm: Move MMU related definitions from config.h to mmu/layout.h

Message ID 20230626033443.2943270-11-Penny.Zheng@arm.com (mailing list archive)
State New, archived
Headers show
Series xen/arm: Add Armv8-R64 MPU support to Xen - Part#1 | expand

Commit Message

Penny Zheng June 26, 2023, 3:34 a.m. UTC 
From: Wei Chen <wei.chen@arm.com>

Xen defines some global configuration macros for Arm in config.h.
We still want to use it for MMU systems, but there are some address
layout related definitions that are defined for MMU systems only.
These definitions could not be used by MPU systems, but adding
ifdefery with CONFIG_HAS_MPU to gate these definitions will result
in a messy and hard-to-read/maintain code.

So we keep some common definitions still in config.h, but move MMU
related definitions to a new file - mmu/layout.h to avoid spreading
"#ifdef" everywhere.

Signed-off-by: Wei Chen <wei.chen@arm.com>
Signed-off-by: Penny Zheng <penny.zheng@arm.com>
---
v1 -> v2:
1. Remove duplicated FIXMAP definitions from config_mmu.h
---
v3:
1. name the new header layout.h
---
 xen/arch/arm/include/asm/config.h     | 127 +----------------------
 xen/arch/arm/include/asm/mmu/layout.h | 141 ++++++++++++++++++++++++++
 2 files changed, 143 insertions(+), 125 deletions(-)
 create mode 100644 xen/arch/arm/include/asm/mmu/layout.h

Comments

Julien Grall July 4, 2023, 9:54 p.m. UTC | #1 
Hi Penny,

On 26/06/2023 04:34, Penny Zheng wrote:
> From: Wei Chen <wei.chen@arm.com>
> 
> Xen defines some global configuration macros for Arm in config.h.
> We still want to use it for MMU systems, but there are some address

Did you mean MPU?

> layout related definitions that are defined for MMU systems only.
> These definitions could not be used by MPU systems, but adding
> ifdefery with CONFIG_HAS_MPU to gate these definitions will result
> in a messy and hard-to-read/maintain code.
> 
> So we keep some common definitions still in config.h, but move MMU
> related definitions to a new file - mmu/layout.h to avoid spreading
> "#ifdef" everywhere.

Just to ease the review, can you add some details which one are 
considered common?

Also, this patch will need to be rebased on top of the latest staging.

> 
> Signed-off-by: Wei Chen <wei.chen@arm.com>
> Signed-off-by: Penny Zheng <penny.zheng@arm.com>
> ---
> v1 -> v2:
> 1. Remove duplicated FIXMAP definitions from config_mmu.h
> ---
> v3:
> 1. name the new header layout.h
> ---
>   xen/arch/arm/include/asm/config.h     | 127 +----------------------
>   xen/arch/arm/include/asm/mmu/layout.h | 141 ++++++++++++++++++++++++++
>   2 files changed, 143 insertions(+), 125 deletions(-)
>   create mode 100644 xen/arch/arm/include/asm/mmu/layout.h
> 
> diff --git a/xen/arch/arm/include/asm/config.h b/xen/arch/arm/include/asm/config.h
> index 30f4665ba9..204b3dec13 100644
> --- a/xen/arch/arm/include/asm/config.h
> +++ b/xen/arch/arm/include/asm/config.h
> @@ -71,131 +71,8 @@
>   #include <xen/const.h>
>   #include <xen/page-size.h>
>   
> -/*
> - * ARM32 layout:
> - *   0  -   2M   Unmapped
> - *   2M -   4M   Xen text, data, bss
> - *   4M -   6M   Fixmap: special-purpose 4K mapping slots
> - *   6M -  10M   Early boot mapping of FDT
> - *   10M - 12M   Livepatch vmap (if compiled in)
> - *
> - *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
> - * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual address
> - *                    space
> - *
> - *   1G -   2G   Xenheap: always-mapped memory
> - *   2G -   4G   Domheap: on-demand-mapped
> - *
> - * ARM64 layout:
> - * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
> - *
> - *  Reserved to identity map Xen
> - *
> - * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
> - *  (Relative offsets)
> - *   0  -   2M   Unmapped
> - *   2M -   4M   Xen text, data, bss
> - *   4M -   6M   Fixmap: special-purpose 4K mapping slots
> - *   6M -  10M   Early boot mapping of FDT
> - *  10M -  12M   Livepatch vmap (if compiled in)
> - *
> - *   1G -   2G   VMAP: ioremap and early_ioremap
> - *
> - *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
> - *
> - * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
> - *  Unused
> - *
> - * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
> - *  1:1 mapping of RAM
> - *
> - * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
> - *  Unused
> - */
> -
> -#ifdef CONFIG_ARM_32
> -#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
> -#else
> -
> -#define SLOT0_ENTRY_BITS  39
> -#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
> -#define SLOT0_ENTRY_SIZE  SLOT0(1)
> -
> -#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
> -#endif
> -
> -#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
> -
> -#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
> -#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
> -
> -#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
> -
> -#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
> -#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
> -
> -#ifdef CONFIG_LIVEPATCH
> -#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + BOOT_FDT_VIRT_SIZE)
> -#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
> -#endif
> -
> -#define HYPERVISOR_VIRT_START  XEN_VIRT_START
> -
> -#ifdef CONFIG_ARM_32
> -
> -#define CONFIG_SEPARATE_XENHEAP 1
> -
> -#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
> -#define FRAMETABLE_SIZE        MB(128-32)
> -#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
> -
> -#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
> -#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
> -
> -#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
> -#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
> -
> -#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
> -#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
> -
> -#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
> -
> -/* Number of domheap pagetable pages required at the second level (2MB mappings) */
> -#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
> -
> -/*
> - * The temporary area is overlapping with the domheap area. This may
> - * be used to create an alias of the first slot containing Xen mappings
> - * when turning on/off the MMU.
> - */
> -#define TEMPORARY_AREA_FIRST_SLOT    (first_table_offset(DOMHEAP_VIRT_START))
> -
> -/* Calculate the address in the temporary area */
> -#define TEMPORARY_AREA_ADDR(addr)                           \
> -     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
> -      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
> -
> -#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
> -
> -#else /* ARM_64 */
> -
> -#define IDENTITY_MAPPING_AREA_NR_L0  4
> -
> -#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
> -#define VMAP_VIRT_SIZE   GB(1)
> -
> -#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
> -#define FRAMETABLE_SIZE        GB(32)
> -#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
> -
> -#define DIRECTMAP_VIRT_START   SLOT0(256)
> -#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
> -#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE - 1)
> -
> -#define XENHEAP_VIRT_START     directmap_virt_start
> -
> -#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
> -
> +#ifndef CONFIG_HAS_MPU

We are not going to introduce HAS_MPU yet in Xen. So can you use 
CONFIG_HAS_MMU?

Also, I would add:

#else
# error "Unknown memory management layout"
#endif

> +#include <asm/mmu/layout.h>
>   #endif
>   
>   #define NR_hypercalls 64
> diff --git a/xen/arch/arm/include/asm/mmu/layout.h b/xen/arch/arm/include/asm/mmu/layout.h
> new file mode 100644
> index 0000000000..8deda6b84d
> --- /dev/null
> +++ b/xen/arch/arm/include/asm/mmu/layout.h
> @@ -0,0 +1,141 @@
> +/* SPDX-License-Identifier: GPL-2.0 */

GPL-2.0 is deprecated and should not be used for new file. This should 
instead be GPL-2.0-only

> +
> +#ifndef __ARM_MMU_LAYOUT_H__
> +#define __ARM_MMU_LAYOUT_H__
> +
> +/*
> + * ARM32 layout:
> + *   0  -   2M   Unmapped
> + *   2M -   4M   Xen text, data, bss
> + *   4M -   6M   Fixmap: special-purpose 4K mapping slots
> + *   6M -  10M   Early boot mapping of FDT
> + *   10M - 12M   Livepatch vmap (if compiled in)
> + *
> + *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
> + * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual address
> + *                    space
> + *
> + *   1G -   2G   Xenheap: always-mapped memory
> + *   2G -   4G   Domheap: on-demand-mapped
> + *
> + * ARM64 layout:
> + * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
> + *
> + *  Reserved to identity map Xen
> + *
> + * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
> + *  (Relative offsets)
> + *   0  -   2M   Unmapped
> + *   2M -   4M   Xen text, data, bss
> + *   4M -   6M   Fixmap: special-purpose 4K mapping slots
> + *   6M -  10M   Early boot mapping of FDT
> + *  10M -  12M   Livepatch vmap (if compiled in)
> + *
> + *   1G -   2G   VMAP: ioremap and early_ioremap
> + *
> + *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
> + *
> + * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
> + *  Unused
> + *
> + * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
> + *  1:1 mapping of RAM
> + *
> + * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
> + *  Unused
> + */
> +
> +#ifdef CONFIG_ARM_32
> +#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
> +#else
> +
> +#define SLOT0_ENTRY_BITS  39
> +#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
> +#define SLOT0_ENTRY_SIZE  SLOT0(1)
> +
> +#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
> +#endif
> +
> +#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
> +
> +#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
> +#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
> +
> +#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
> +
> +#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
> +#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
> +
> +#ifdef CONFIG_LIVEPATCH
> +#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + BOOT_FDT_VIRT_SIZE)
> +#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
> +#endif
> +
> +#define HYPERVISOR_VIRT_START  XEN_VIRT_START
> +
> +#ifdef CONFIG_ARM_32
> +
> +#define CONFIG_SEPARATE_XENHEAP 1
> +
> +#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
> +#define FRAMETABLE_SIZE        MB(128-32)
> +#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
> +
> +#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
> +#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
> +
> +#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
> +#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
> +
> +#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
> +#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
> +
> +#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
> +
> +/* Number of domheap pagetable pages required at the second level (2MB mappings) */
> +#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
> +
> +/*
> + * The temporary area is overlapping with the domheap area. This may
> + * be used to create an alias of the first slot containing Xen mappings
> + * when turning on/off the MMU.
> + */
> +#define TEMPORARY_AREA_FIRST_SLOT    (first_table_offset(DOMHEAP_VIRT_START))
> +
> +/* Calculate the address in the temporary area */
> +#define TEMPORARY_AREA_ADDR(addr)                           \
> +     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
> +      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
> +
> +#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
> +
> +#else /* ARM_64 */
> +
> +#define IDENTITY_MAPPING_AREA_NR_L0  4
> +
> +#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
> +#define VMAP_VIRT_SIZE   GB(1)
> +
> +#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
> +#define FRAMETABLE_SIZE        GB(32)
> +#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
> +
> +#define DIRECTMAP_VIRT_START   SLOT0(256)
> +#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
> +#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE - 1)
> +
> +#define XENHEAP_VIRT_START     directmap_virt_start
> +
> +#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
> +
> +#endif
> +
> +#endif /* __ARM_MMU_LAYOUT_H__ */
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * indent-tabs-mode: nil
> + * End:
> + */

Cheers,
Penny Zheng July 5, 2023, 6:51 a.m. UTC | #2 
Hi Julien

On 2023/7/5 05:54, Julien Grall wrote:
> Hi Penny,
> 
> On 26/06/2023 04:34, Penny Zheng wrote:
>> From: Wei Chen <wei.chen@arm.com>
>>
>> Xen defines some global configuration macros for Arm in config.h.
>> We still want to use it for MMU systems, but there are some address
> 
> Did you mean MPU?
> 

yes, typo

>> layout related definitions that are defined for MMU systems only.
>> These definitions could not be used by MPU systems, but adding
>> ifdefery with CONFIG_HAS_MPU to gate these definitions will result
>> in a messy and hard-to-read/maintain code.
>>
>> So we keep some common definitions still in config.h, but move MMU
>> related definitions to a new file - mmu/layout.h to avoid spreading
>> "#ifdef" everywhere.
> 
> Just to ease the review, can you add some details which one are 
> considered common?
> 

Sure,
IMO， the only part left in common is as follows:
```
#ifdef CONFIG_ARM_64

#define FRAMETABLE_SIZE        GB(32)
#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))

#endif
```
I couldn't figure a proper way to remove the limit for MPU system.

when calculating variable "pdx_group_valid", which is defined as
```
unsigned long __read_mostly pdx_group_valid[BITS_TO_LONGS(
     (FRAMETABLE_NR + PDX_GROUP_COUNT - 1)/PDX_GROUP_COUNT)] = {[0] = 1}
'''

It relies on FRAMETABLE_NR to limit array length. If we are trying to
get rid of the limit for the MPU, it may bring a lot of changes in pdx 
common codes, like, variable "pdx_group_valid" needs to be allocated in 
runtime, according actual frametable size, at least for MPU case.


> Also, this patch will need to be rebased on top of the latest staging.

sure,

> 
>>
>> Signed-off-by: Wei Chen <wei.chen@arm.com>
>> Signed-off-by: Penny Zheng <penny.zheng@arm.com>
>> ---
>> v1 -> v2:
>> 1. Remove duplicated FIXMAP definitions from config_mmu.h
>> ---
>> v3:
>> 1. name the new header layout.h
>> ---
>>   xen/arch/arm/include/asm/config.h     | 127 +----------------------
>>   xen/arch/arm/include/asm/mmu/layout.h | 141 ++++++++++++++++++++++++++
>>   2 files changed, 143 insertions(+), 125 deletions(-)
>>   create mode 100644 xen/arch/arm/include/asm/mmu/layout.h
>>
>> diff --git a/xen/arch/arm/include/asm/config.h 
>> b/xen/arch/arm/include/asm/config.h
>> index 30f4665ba9..204b3dec13 100644
>> --- a/xen/arch/arm/include/asm/config.h
>> +++ b/xen/arch/arm/include/asm/config.h
>> @@ -71,131 +71,8 @@
>>   #include <xen/const.h>
>>   #include <xen/page-size.h>
>> -/*
>> - * ARM32 layout:
>> - *   0  -   2M   Unmapped
>> - *   2M -   4M   Xen text, data, bss
>> - *   4M -   6M   Fixmap: special-purpose 4K mapping slots
>> - *   6M -  10M   Early boot mapping of FDT
>> - *   10M - 12M   Livepatch vmap (if compiled in)
>> - *
>> - *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
>> - * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual 
>> address
>> - *                    space
>> - *
>> - *   1G -   2G   Xenheap: always-mapped memory
>> - *   2G -   4G   Domheap: on-demand-mapped
>> - *
>> - * ARM64 layout:
>> - * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
>> - *
>> - *  Reserved to identity map Xen
>> - *
>> - * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
>> - *  (Relative offsets)
>> - *   0  -   2M   Unmapped
>> - *   2M -   4M   Xen text, data, bss
>> - *   4M -   6M   Fixmap: special-purpose 4K mapping slots
>> - *   6M -  10M   Early boot mapping of FDT
>> - *  10M -  12M   Livepatch vmap (if compiled in)
>> - *
>> - *   1G -   2G   VMAP: ioremap and early_ioremap
>> - *
>> - *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
>> - *
>> - * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
>> - *  Unused
>> - *
>> - * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
>> - *  1:1 mapping of RAM
>> - *
>> - * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
>> - *  Unused
>> - */
>> -
>> -#ifdef CONFIG_ARM_32
>> -#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
>> -#else
>> -
>> -#define SLOT0_ENTRY_BITS  39
>> -#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
>> -#define SLOT0_ENTRY_SIZE  SLOT0(1)
>> -
>> -#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
>> -#endif
>> -
>> -#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
>> -
>> -#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
>> -#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
>> -
>> -#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
>> -
>> -#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
>> -#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
>> -
>> -#ifdef CONFIG_LIVEPATCH
>> -#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + 
>> BOOT_FDT_VIRT_SIZE)
>> -#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
>> -#endif
>> -
>> -#define HYPERVISOR_VIRT_START  XEN_VIRT_START
>> -
>> -#ifdef CONFIG_ARM_32
>> -
>> -#define CONFIG_SEPARATE_XENHEAP 1
>> -
>> -#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
>> -#define FRAMETABLE_SIZE        MB(128-32)
>> -#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>> -
>> -#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
>> -#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
>> -
>> -#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
>> -#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
>> -
>> -#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
>> -#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
>> -
>> -#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
>> -
>> -/* Number of domheap pagetable pages required at the second level 
>> (2MB mappings) */
>> -#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
>> -
>> -/*
>> - * The temporary area is overlapping with the domheap area. This may
>> - * be used to create an alias of the first slot containing Xen mappings
>> - * when turning on/off the MMU.
>> - */
>> -#define TEMPORARY_AREA_FIRST_SLOT    
>> (first_table_offset(DOMHEAP_VIRT_START))
>> -
>> -/* Calculate the address in the temporary area */
>> -#define TEMPORARY_AREA_ADDR(addr)                           \
>> -     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
>> -      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
>> -
>> -#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
>> -
>> -#else /* ARM_64 */
>> -
>> -#define IDENTITY_MAPPING_AREA_NR_L0  4
>> -
>> -#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
>> -#define VMAP_VIRT_SIZE   GB(1)
>> -
>> -#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
>> -#define FRAMETABLE_SIZE        GB(32)
>> -#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>> -
>> -#define DIRECTMAP_VIRT_START   SLOT0(256)
>> -#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
>> -#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE 
>> - 1)
>> -
>> -#define XENHEAP_VIRT_START     directmap_virt_start
>> -
>> -#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
>> -
>> +#ifndef CONFIG_HAS_MPU
> 
> We are not going to introduce HAS_MPU yet in Xen. So can you use 
> CONFIG_HAS_MMU?
> 
> Also, I would add:
> 
> #else
> # error "Unknown memory management layout"
> #endif
> 

Sure, will do.

>> +#include <asm/mmu/layout.h>
>>   #endif
>>   #define NR_hypercalls 64
>> diff --git a/xen/arch/arm/include/asm/mmu/layout.h 
>> b/xen/arch/arm/include/asm/mmu/layout.h
>> new file mode 100644
>> index 0000000000..8deda6b84d
>> --- /dev/null
>> +++ b/xen/arch/arm/include/asm/mmu/layout.h
>> @@ -0,0 +1,141 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
> 
> GPL-2.0 is deprecated and should not be used for new file. This should 
> instead be GPL-2.0-only
> 

understood.

>> +
>> +#ifndef __ARM_MMU_LAYOUT_H__
>> +#define __ARM_MMU_LAYOUT_H__
>> +
>> +/*
>> + * ARM32 layout:
>> + *   0  -   2M   Unmapped
>> + *   2M -   4M   Xen text, data, bss
>> + *   4M -   6M   Fixmap: special-purpose 4K mapping slots
>> + *   6M -  10M   Early boot mapping of FDT
>> + *   10M - 12M   Livepatch vmap (if compiled in)
>> + *
>> + *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
>> + * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual 
>> address
>> + *                    space
>> + *
>> + *   1G -   2G   Xenheap: always-mapped memory
>> + *   2G -   4G   Domheap: on-demand-mapped
>> + *
>> + * ARM64 layout:
>> + * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
>> + *
>> + *  Reserved to identity map Xen
>> + *
>> + * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
>> + *  (Relative offsets)
>> + *   0  -   2M   Unmapped
>> + *   2M -   4M   Xen text, data, bss
>> + *   4M -   6M   Fixmap: special-purpose 4K mapping slots
>> + *   6M -  10M   Early boot mapping of FDT
>> + *  10M -  12M   Livepatch vmap (if compiled in)
>> + *
>> + *   1G -   2G   VMAP: ioremap and early_ioremap
>> + *
>> + *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
>> + *
>> + * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
>> + *  Unused
>> + *
>> + * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
>> + *  1:1 mapping of RAM
>> + *
>> + * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
>> + *  Unused
>> + */
>> +
>> +#ifdef CONFIG_ARM_32
>> +#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
>> +#else
>> +
>> +#define SLOT0_ENTRY_BITS  39
>> +#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
>> +#define SLOT0_ENTRY_SIZE  SLOT0(1)
>> +
>> +#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
>> +#endif
>> +
>> +#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
>> +
>> +#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
>> +#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
>> +
>> +#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
>> +
>> +#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
>> +#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
>> +
>> +#ifdef CONFIG_LIVEPATCH
>> +#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + 
>> BOOT_FDT_VIRT_SIZE)
>> +#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
>> +#endif
>> +
>> +#define HYPERVISOR_VIRT_START  XEN_VIRT_START
>> +
>> +#ifdef CONFIG_ARM_32
>> +
>> +#define CONFIG_SEPARATE_XENHEAP 1
>> +
>> +#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
>> +#define FRAMETABLE_SIZE        MB(128-32)
>> +#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>> +
>> +#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
>> +#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
>> +
>> +#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
>> +#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
>> +
>> +#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
>> +#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
>> +
>> +#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
>> +
>> +/* Number of domheap pagetable pages required at the second level 
>> (2MB mappings) */
>> +#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
>> +
>> +/*
>> + * The temporary area is overlapping with the domheap area. This may
>> + * be used to create an alias of the first slot containing Xen mappings
>> + * when turning on/off the MMU.
>> + */
>> +#define TEMPORARY_AREA_FIRST_SLOT    
>> (first_table_offset(DOMHEAP_VIRT_START))
>> +
>> +/* Calculate the address in the temporary area */
>> +#define TEMPORARY_AREA_ADDR(addr)                           \
>> +     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
>> +      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
>> +
>> +#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
>> +
>> +#else /* ARM_64 */
>> +
>> +#define IDENTITY_MAPPING_AREA_NR_L0  4
>> +
>> +#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
>> +#define VMAP_VIRT_SIZE   GB(1)
>> +
>> +#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
>> +#define FRAMETABLE_SIZE        GB(32)
>> +#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>> +
>> +#define DIRECTMAP_VIRT_START   SLOT0(256)
>> +#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
>> +#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE 
>> - 1)
>> +
>> +#define XENHEAP_VIRT_START     directmap_virt_start
>> +
>> +#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
>> +
>> +#endif
>> +
>> +#endif /* __ARM_MMU_LAYOUT_H__ */
>> +/*
>> + * Local variables:
>> + * mode: C
>> + * c-file-style: "BSD"
>> + * c-basic-offset: 4
>> + * indent-tabs-mode: nil
>> + * End:
>> + */
> 
> Cheers,
>
Julien Grall July 5, 2023, 10:30 a.m. UTC | #3 
Hi Penny,

On 05/07/2023 07:51, Penny Zheng wrote:
> On 2023/7/5 05:54, Julien Grall wrote:
>> Hi Penny,
>>
>> On 26/06/2023 04:34, Penny Zheng wrote:
>>> From: Wei Chen <wei.chen@arm.com>
>>>
>>> Xen defines some global configuration macros for Arm in config.h.
>>> We still want to use it for MMU systems, but there are some address
>>
>> Did you mean MPU?
>>
> 
> yes, typo
> 
>>> layout related definitions that are defined for MMU systems only.
>>> These definitions could not be used by MPU systems, but adding
>>> ifdefery with CONFIG_HAS_MPU to gate these definitions will result
>>> in a messy and hard-to-read/maintain code.
>>>
>>> So we keep some common definitions still in config.h, but move MMU
>>> related definitions to a new file - mmu/layout.h to avoid spreading
>>> "#ifdef" everywhere.
>>
>> Just to ease the review, can you add some details which one are 
>> considered common?
>>
> 
> Sure,
> IMO， the only part left in common is as follows:
> ```
> #ifdef CONFIG_ARM_64
> 
> #define FRAMETABLE_SIZE        GB(32)
> #define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
> 
> #endif
> ```

Hmmm... Looking at the result of the patch, you moved FRAMETABLE_SIZE 
and FRAMETABLE_NR in layout.h. Also, I can't find any layout specific 
define in config.h. So I think the paragraph could be dropped.

> I couldn't figure a proper way to remove the limit for MPU system.
> 
> when calculating variable "pdx_group_valid", which is defined as
> ```
> unsigned long __read_mostly pdx_group_valid[BITS_TO_LONGS(
>      (FRAMETABLE_NR + PDX_GROUP_COUNT - 1)/PDX_GROUP_COUNT)] = {[0] = 1}
> '''
> 
> It relies on FRAMETABLE_NR to limit array length. If we are trying to
> get rid of the limit for the MPU, it may bring a lot of changes in pdx 
> common codes, like, variable "pdx_group_valid" needs to be allocated in 
> runtime, according actual frametable size, at least for MPU case.

The main problem is that, at least on Arm, the PDX is initialized before 
you can allocate any memory. You should be able to re-order the code so 
we populate the boot allocator first.

But I don't think this is worth it right now as, if I am not mistaken, 
the pdx_group_valid is only 256 bytes on Arm64.

Cheers,
Penny Zheng July 6, 2023, 7:36 a.m. UTC | #4 
Hi Julien

On 2023/7/5 18:30, Julien Grall wrote:
> Hi Penny,
> 
> On 05/07/2023 07:51, Penny Zheng wrote:
>> On 2023/7/5 05:54, Julien Grall wrote:
>>> Hi Penny,
>>>
>>> On 26/06/2023 04:34, Penny Zheng wrote:
>>>> From: Wei Chen <wei.chen@arm.com>
>>>>
>>>> Xen defines some global configuration macros for Arm in config.h.
>>>> We still want to use it for MMU systems, but there are some address
>>>
>>> Did you mean MPU?
>>>
>>
>> yes, typo
>>
>>>> layout related definitions that are defined for MMU systems only.
>>>> These definitions could not be used by MPU systems, but adding
>>>> ifdefery with CONFIG_HAS_MPU to gate these definitions will result
>>>> in a messy and hard-to-read/maintain code.
>>>>
>>>> So we keep some common definitions still in config.h, but move MMU
>>>> related definitions to a new file - mmu/layout.h to avoid spreading
>>>> "#ifdef" everywhere.
>>>
>>> Just to ease the review, can you add some details which one are 
>>> considered common?
>>>
>>
>> Sure,
>> IMO， the only part left in common is as follows:
>> ```
>> #ifdef CONFIG_ARM_64
>>
>> #define FRAMETABLE_SIZE        GB(32)
>> #define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>>
>> #endif
>> ```
> 
> Hmmm... Looking at the result of the patch, you moved FRAMETABLE_SIZE 
> and FRAMETABLE_NR in layout.h. Also, I can't find any layout specific 
> define in config.h. So I think the paragraph could be dropped.
> 

That's because I define this same snippet in both mmu/layout.h and
mpu/layout.h, see [PATCH v3 23/52] xen/arm: create mpu/layout.h for MPU 
related address definitions.
So it is common for both mmu/layout.h and mpu/layout.h.
We could leave it later for discussion.

>> I couldn't figure a proper way to remove the limit for MPU system.
>>
>> when calculating variable "pdx_group_valid", which is defined as
>> ```
>> unsigned long __read_mostly pdx_group_valid[BITS_TO_LONGS(
>>      (FRAMETABLE_NR + PDX_GROUP_COUNT - 1)/PDX_GROUP_COUNT)] = {[0] = 1}
>> '''
>>
>> It relies on FRAMETABLE_NR to limit array length. If we are trying to
>> get rid of the limit for the MPU, it may bring a lot of changes in pdx 
>> common codes, like, variable "pdx_group_valid" needs to be allocated 
>> in runtime, according actual frametable size, at least for MPU case.
> 
> The main problem is that, at least on Arm, the PDX is initialized before 
> you can allocate any memory. You should be able to re-order the code so 
> we populate the boot allocator first.
> 
> But I don't think this is worth it right now as, if I am not mistaken, 
> the pdx_group_valid is only 256 bytes on Arm64.
> 
> Cheers,
>
Julien Grall July 6, 2023, 8:08 a.m. UTC | #5 
Hi Penny,

On 06/07/2023 08:36, Penny Zheng wrote:
> Hi Julien
> 
> On 2023/7/5 18:30, Julien Grall wrote:
>> Hi Penny,
>>
>> On 05/07/2023 07:51, Penny Zheng wrote:
>>> On 2023/7/5 05:54, Julien Grall wrote:
>>>> Hi Penny,
>>>>
>>>> On 26/06/2023 04:34, Penny Zheng wrote:
>>>>> From: Wei Chen <wei.chen@arm.com>
>>>>>
>>>>> Xen defines some global configuration macros for Arm in config.h.
>>>>> We still want to use it for MMU systems, but there are some address
>>>>
>>>> Did you mean MPU?
>>>>
>>>
>>> yes, typo
>>>
>>>>> layout related definitions that are defined for MMU systems only.
>>>>> These definitions could not be used by MPU systems, but adding
>>>>> ifdefery with CONFIG_HAS_MPU to gate these definitions will result
>>>>> in a messy and hard-to-read/maintain code.
>>>>>
>>>>> So we keep some common definitions still in config.h, but move MMU
>>>>> related definitions to a new file - mmu/layout.h to avoid spreading
>>>>> "#ifdef" everywhere.
>>>>
>>>> Just to ease the review, can you add some details which one are 
>>>> considered common?
>>>>
>>>
>>> Sure,
>>> IMO， the only part left in common is as follows:
>>> ```
>>> #ifdef CONFIG_ARM_64
>>>
>>> #define FRAMETABLE_SIZE        GB(32)
>>> #define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
>>>
>>> #endif
>>> ```
>>
>> Hmmm... Looking at the result of the patch, you moved FRAMETABLE_SIZE 
>> and FRAMETABLE_NR in layout.h. Also, I can't find any layout specific 
>> define in config.h. So I think the paragraph could be dropped.
>>
> 
> That's because I define this same snippet in both mmu/layout.h and
> mpu/layout.h, see [PATCH v3 23/52] xen/arm: create mpu/layout.h for MPU 
> related address definitions.
> So it is common for both mmu/layout.h and mpu/layout.h.
This is different from what you wrote in the commit message:

"So we keep some common definitions still in config.h"

 From the perspective of this patch you moved everything related to the 
layout in mmu/layout.h. Whether there might be duplication in the future 
is a different subject.

In this case, I would prefer the duplication because the size of the 
frametable really depend on how you configure the layout. So it should 
stay close the rest of the defines.

Cheers,
diff mbox series

Patch

diff --git a/xen/arch/arm/include/asm/config.h b/xen/arch/arm/include/asm/config.h
index 30f4665ba9..204b3dec13 100644
--- a/xen/arch/arm/include/asm/config.h
+++ b/xen/arch/arm/include/asm/config.h
@@ -71,131 +71,8 @@ 
 #include <xen/const.h>
 #include <xen/page-size.h>
 
-/*
- * ARM32 layout:
- *   0  -   2M   Unmapped
- *   2M -   4M   Xen text, data, bss
- *   4M -   6M   Fixmap: special-purpose 4K mapping slots
- *   6M -  10M   Early boot mapping of FDT
- *   10M - 12M   Livepatch vmap (if compiled in)
- *
- *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
- * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual address
- *                    space
- *
- *   1G -   2G   Xenheap: always-mapped memory
- *   2G -   4G   Domheap: on-demand-mapped
- *
- * ARM64 layout:
- * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
- *
- *  Reserved to identity map Xen
- *
- * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
- *  (Relative offsets)
- *   0  -   2M   Unmapped
- *   2M -   4M   Xen text, data, bss
- *   4M -   6M   Fixmap: special-purpose 4K mapping slots
- *   6M -  10M   Early boot mapping of FDT
- *  10M -  12M   Livepatch vmap (if compiled in)
- *
- *   1G -   2G   VMAP: ioremap and early_ioremap
- *
- *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
- *
- * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
- *  Unused
- *
- * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
- *  1:1 mapping of RAM
- *
- * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
- *  Unused
- */
-
-#ifdef CONFIG_ARM_32
-#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
-#else
-
-#define SLOT0_ENTRY_BITS  39
-#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
-#define SLOT0_ENTRY_SIZE  SLOT0(1)
-
-#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
-#endif
-
-#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
-
-#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
-#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
-
-#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
-
-#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
-#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
-
-#ifdef CONFIG_LIVEPATCH
-#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + BOOT_FDT_VIRT_SIZE)
-#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
-#endif
-
-#define HYPERVISOR_VIRT_START  XEN_VIRT_START
-
-#ifdef CONFIG_ARM_32
-
-#define CONFIG_SEPARATE_XENHEAP 1
-
-#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
-#define FRAMETABLE_SIZE        MB(128-32)
-#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
-
-#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
-#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
-
-#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
-#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
-
-#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
-#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
-
-#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
-
-/* Number of domheap pagetable pages required at the second level (2MB mappings) */
-#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
-
-/*
- * The temporary area is overlapping with the domheap area. This may
- * be used to create an alias of the first slot containing Xen mappings
- * when turning on/off the MMU.
- */
-#define TEMPORARY_AREA_FIRST_SLOT    (first_table_offset(DOMHEAP_VIRT_START))
-
-/* Calculate the address in the temporary area */
-#define TEMPORARY_AREA_ADDR(addr)                           \
-     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
-      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
-
-#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
-
-#else /* ARM_64 */
-
-#define IDENTITY_MAPPING_AREA_NR_L0  4
-
-#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
-#define VMAP_VIRT_SIZE   GB(1)
-
-#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
-#define FRAMETABLE_SIZE        GB(32)
-#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
-
-#define DIRECTMAP_VIRT_START   SLOT0(256)
-#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
-#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE - 1)
-
-#define XENHEAP_VIRT_START     directmap_virt_start
-
-#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
-
+#ifndef CONFIG_HAS_MPU
+#include <asm/mmu/layout.h>
 #endif
 
 #define NR_hypercalls 64
diff --git a/xen/arch/arm/include/asm/mmu/layout.h b/xen/arch/arm/include/asm/mmu/layout.h
new file mode 100644
index 0000000000..8deda6b84d
--- /dev/null
+++ b/xen/arch/arm/include/asm/mmu/layout.h
@@ -0,0 +1,141 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ARM_MMU_LAYOUT_H__
+#define __ARM_MMU_LAYOUT_H__
+
+/*
+ * ARM32 layout:
+ *   0  -   2M   Unmapped
+ *   2M -   4M   Xen text, data, bss
+ *   4M -   6M   Fixmap: special-purpose 4K mapping slots
+ *   6M -  10M   Early boot mapping of FDT
+ *   10M - 12M   Livepatch vmap (if compiled in)
+ *
+ *  32M - 128M   Frametable: 32 bytes per page for 12GB of RAM
+ * 256M -   1G   VMAP: ioremap and early_ioremap use this virtual address
+ *                    space
+ *
+ *   1G -   2G   Xenheap: always-mapped memory
+ *   2G -   4G   Domheap: on-demand-mapped
+ *
+ * ARM64 layout:
+ * 0x0000000000000000 - 0x000001ffffffffff (2TB, L0 slots [0..3])
+ *
+ *  Reserved to identity map Xen
+ *
+ * 0x0000020000000000 - 0x0000027fffffffff (512GB, L0 slot [4])
+ *  (Relative offsets)
+ *   0  -   2M   Unmapped
+ *   2M -   4M   Xen text, data, bss
+ *   4M -   6M   Fixmap: special-purpose 4K mapping slots
+ *   6M -  10M   Early boot mapping of FDT
+ *  10M -  12M   Livepatch vmap (if compiled in)
+ *
+ *   1G -   2G   VMAP: ioremap and early_ioremap
+ *
+ *  32G -  64G   Frametable: 56 bytes per page for 2TB of RAM
+ *
+ * 0x0000028000000000 - 0x00007fffffffffff (125TB, L0 slots [5..255])
+ *  Unused
+ *
+ * 0x0000800000000000 - 0x000084ffffffffff (5TB, L0 slots [256..265])
+ *  1:1 mapping of RAM
+ *
+ * 0x0000850000000000 - 0x0000ffffffffffff (123TB, L0 slots [266..511])
+ *  Unused
+ */
+
+#ifdef CONFIG_ARM_32
+#define XEN_VIRT_START          _AT(vaddr_t, MB(2))
+#else
+
+#define SLOT0_ENTRY_BITS  39
+#define SLOT0(slot) (_AT(vaddr_t,slot) << SLOT0_ENTRY_BITS)
+#define SLOT0_ENTRY_SIZE  SLOT0(1)
+
+#define XEN_VIRT_START          (SLOT0(4) + _AT(vaddr_t, MB(2)))
+#endif
+
+#define XEN_VIRT_SIZE           _AT(vaddr_t, MB(2))
+
+#define FIXMAP_VIRT_START       (XEN_VIRT_START + XEN_VIRT_SIZE)
+#define FIXMAP_VIRT_SIZE        _AT(vaddr_t, MB(2))
+
+#define FIXMAP_ADDR(n)          (FIXMAP_VIRT_START + (n) * PAGE_SIZE)
+
+#define BOOT_FDT_VIRT_START     (FIXMAP_VIRT_START + FIXMAP_VIRT_SIZE)
+#define BOOT_FDT_VIRT_SIZE      _AT(vaddr_t, MB(4))
+
+#ifdef CONFIG_LIVEPATCH
+#define LIVEPATCH_VMAP_START    (BOOT_FDT_VIRT_START + BOOT_FDT_VIRT_SIZE)
+#define LIVEPATCH_VMAP_SIZE    _AT(vaddr_t, MB(2))
+#endif
+
+#define HYPERVISOR_VIRT_START  XEN_VIRT_START
+
+#ifdef CONFIG_ARM_32
+
+#define CONFIG_SEPARATE_XENHEAP 1
+
+#define FRAMETABLE_VIRT_START  _AT(vaddr_t, MB(32))
+#define FRAMETABLE_SIZE        MB(128-32)
+#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
+
+#define VMAP_VIRT_START        _AT(vaddr_t, MB(256))
+#define VMAP_VIRT_SIZE         _AT(vaddr_t, GB(1) - MB(256))
+
+#define XENHEAP_VIRT_START     _AT(vaddr_t, GB(1))
+#define XENHEAP_VIRT_SIZE      _AT(vaddr_t, GB(1))
+
+#define DOMHEAP_VIRT_START     _AT(vaddr_t, GB(2))
+#define DOMHEAP_VIRT_SIZE      _AT(vaddr_t, GB(2))
+
+#define DOMHEAP_ENTRIES        1024  /* 1024 2MB mapping slots */
+
+/* Number of domheap pagetable pages required at the second level (2MB mappings) */
+#define DOMHEAP_SECOND_PAGES (DOMHEAP_VIRT_SIZE >> FIRST_SHIFT)
+
+/*
+ * The temporary area is overlapping with the domheap area. This may
+ * be used to create an alias of the first slot containing Xen mappings
+ * when turning on/off the MMU.
+ */
+#define TEMPORARY_AREA_FIRST_SLOT    (first_table_offset(DOMHEAP_VIRT_START))
+
+/* Calculate the address in the temporary area */
+#define TEMPORARY_AREA_ADDR(addr)                           \
+     (((addr) & ~XEN_PT_LEVEL_MASK(1)) |                    \
+      (TEMPORARY_AREA_FIRST_SLOT << XEN_PT_LEVEL_SHIFT(1)))
+
+#define TEMPORARY_XEN_VIRT_START    TEMPORARY_AREA_ADDR(XEN_VIRT_START)
+
+#else /* ARM_64 */
+
+#define IDENTITY_MAPPING_AREA_NR_L0  4
+
+#define VMAP_VIRT_START  (SLOT0(4) + GB(1))
+#define VMAP_VIRT_SIZE   GB(1)
+
+#define FRAMETABLE_VIRT_START  (SLOT0(4) + GB(32))
+#define FRAMETABLE_SIZE        GB(32)
+#define FRAMETABLE_NR          (FRAMETABLE_SIZE / sizeof(*frame_table))
+
+#define DIRECTMAP_VIRT_START   SLOT0(256)
+#define DIRECTMAP_SIZE         (SLOT0_ENTRY_SIZE * (266 - 256))
+#define DIRECTMAP_VIRT_END     (DIRECTMAP_VIRT_START + DIRECTMAP_SIZE - 1)
+
+#define XENHEAP_VIRT_START     directmap_virt_start
+
+#define HYPERVISOR_VIRT_END    DIRECTMAP_VIRT_END
+
+#endif
+
+#endif /* __ARM_MMU_LAYOUT_H__ */
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */