Re: [PATCH v3 0/7] Unflattening and relocation of host device tree

[Jan Beulich <jbeulich@xxxxxxxx>]

On 17.12.2024 17:32, Oleksii Kurochko wrote:
> The current patch series introduces the relocation of the host device tree 
> file
> to free up low memory and also it is expected that discard_initial_modules()
> will be called sooner or later, it will discard the FDT boot module,
> and remove_early_mappings() will destroy the early mappings.
> 
> In addition to relocation, unflattening is introduced to create the tree of
> struct device_node for the host device tree.
> 
> To implement this, several things have been introduced:
>  - destroy_xen_mappings() function, which removes page mappings from Xen's
>    page tables. This is necessary for clear_fixmap().
>  - {set,clear}_fixmap() functions to manage mappings in the fixmap region,
>    which are expected to be used in copy_from_paddr() to copy the FDT to Xen's
>    heap.
>  - Introduce new config CONFIG_QEMU which is going to be used to cover changes
>    connected to QEMU virtual board. It will be used during introduction of 
> stubs
>    for clean_and_invalidate_dcache_va_range() and clean_dcache_va_range(),
>    which are expected to be used in copy_from_paddr() and flush_page_to_ram(),
>    which in turn are expected to be used during the call to xvmalloc_array() 
> in
>    relocate_fdt().
>    In case of QEMU cached related functions are implemented as returning 0 as
>    QEMU doesn't model cache ( and so CMO extensions ). For others cases, it is
>    introduced as -ENOSUPP as h/w could support CMO extension ( or hardware
>    specific insertions ) and it will need to update implementation of the
>    mentioned functions.
>  - The introduction of copy_from_paddr() to copy the FDT to an address
>    allocated in Xen's heap.
> 
> ---
> Changes in v3:
>  - Add some Acks for the patches. All the patches are Acked except:
>      [PATCH v3 1/7] xen/riscv: update layout table in config.h
>      [PATCH v3 5/7] xen/riscv: implement data and instruction cache operations
>  - Other changes please look at the specific patch.
> ---
> Changes in v2:
>  - Update the cover letter.
>  - Introduce new patch with aligning of upper bounds in the layout table in
>    config.h with the definitions below which are inclusive.
>  - Other changes please look at the specific patch.
> ---
> 
> Oleksii Kurochko (7):
>   xen/riscv: update layout table in config.h
>   xen/riscv: add destroy_xen_mappings() to remove mappings in Xen page
>     tables
>   xen/riscv: reorder includes in asm/page.h alphabetically
>   xen/riscv: add {set,clear}_fixmap() functions for managing fixmap
>     entries

Please can you avoid re-posting patches that were already committed (the
latter three)?

Jan