On 5/20/25 5:16 PM, Jan Beulich wrote:
On 09.05.2025 17:57, Oleksii Kurochko wrote:
These utilities are needed for building and managing RISC-V guest page
tables and MMIO mappings by using functions map_regions_p2mt() and
guest_physmap_add_entry().
To implement p2m mapping functionality the following is introduced:
- Define P2M root level/order and entry count.
- Introdude radix type for p2m types as it isn't enough free bits in pte
and the helpers (p2m_type_radix_{get,set}()) to deal with them.
- Introduce p2m_is_*() helpers() as pte_is_*() helpers are checking
the valid bit set in the PTE but we have to check p2m_type instead
(look at the comment above p2m_is_valid() for some details).
May I suggest to name them at least p2me_is_*() then, as they check entries
rather than entire P2Ms? Same perhaps elsewhere.
Sure, I will handle that during a work on v2.
- Introduce helper to set p2m's pte permission: p2m_set_permissions().
- Introduce helper to create p2m entry based on mfn, p2m_type_t and
p2m_access_t.
- Introduce helper to generate table entry with correct attributes:
page_to_p2m_table().
- Introduce p2m page allocation function: p2m_alloc_page().
- Introduce functions to write/remove p2m's entries: p2m_{write,remove}_pte().
- Introduce function to allocate p2m table: p2m_create_table().
- Introduce functions used to free p2m entry.
- Introduce function for table walking: p2m_next_level().
- Introduce function to insert an entry in the p2m (p2m_set_entry()).
- Introduce superpage splitting: p2m_split_superpage()).
- Introduce page table type defines (PGT_{none,writable_page}, etc).
Signed-off-by: Oleksii Kurochko<oleksii.kuroc...@gmail.com>
---
xen/arch/riscv/include/asm/mm.h | 32 +-
xen/arch/riscv/include/asm/p2m.h | 17 +-
xen/arch/riscv/include/asm/page.h | 11 +
xen/arch/riscv/p2m.c | 780 ++++++++++++++++++++++++++++++
4 files changed, 829 insertions(+), 11 deletions(-)
It's imo too many things you do in one go here.
I will split to smaller patches.
Thanks.
~ Oleksii
