On Wed, 2024-02-14 at 07:38 -0800, Tushar Sugandhi wrote:
> Currently, the mechanism to map and unmap segments to the kimage
> structure is not available to the subsystems outside of kexec. This
> functionality is needed when IMA is allocating the memory segments
> during kexec 'load' operation. Implement functions to map and unmap
> segments to kimage.
>
> Implement kimage_map_segment() to enable mapping of IMA buffer source
> pages to the kimage structure post kexec 'load'. This function,
> accepting a kimage pointer, an address, and a size, will gather the
> source pages within the specified address range, create an array of page
> pointers, and map these to a contiguous virtual address range. The
> function returns the start of this range if successful, or NULL if
> unsuccessful.
>
> Implement kimage_unmap_segment() for unmapping segments
> using vunmap(). Relocate 'for_each_kimage_entry()' macro from
> kexec_core.c to kexec.h for broader accessibility.
>
> Signed-off-by: Tushar Sugandhi <tusharsu@xxxxxxxxxxxxxxxxxxx>
> ---
> include/linux/kexec.h | 13 ++++++++++
> kernel/kexec_core.c | 59 +++++++++++++++++++++++++++++++++++++++----
> 2 files changed, 67 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 400cb6c02176..3145447eb77a 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -486,6 +486,11 @@ static inline void arch_kexec_pre_free_pages(void *vaddr,
> unsigned int pages) {
> static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
> #endif
>
> +#define for_each_kimage_entry(image, ptr, entry) \
> + for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
> + ptr = (entry & IND_INDIRECTION) ? \
> + boot_phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
> +
I don't see a reason for moving this macro.
Mimi
