On Sat, 2023-12-23 at 02:52 +0300, Kirill A. Shutemov wrote: > The helper complements kernel_ident_mapping_init(): it frees the > identity mapping that was previously allocated. It will be used in the > error path to free a partially allocated mapping or if the mapping is no > longer needed. > > The caller provides a struct x86_mapping_info with the free_pgd_page() > callback hooked up and the pgd_t to free. > > Signed-off-by: Kirill A. Shutemov <[email protected]> > --- > arch/x86/include/asm/init.h | 3 ++ > arch/x86/mm/ident_map.c | 73 +++++++++++++++++++++++++++++++++++++ > 2 files changed, 76 insertions(+) > > diff --git a/arch/x86/include/asm/init.h b/arch/x86/include/asm/init.h > index cc9ccf61b6bd..14d72727d7ee 100644 > --- a/arch/x86/include/asm/init.h > +++ b/arch/x86/include/asm/init.h > @@ -6,6 +6,7 @@ > > struct x86_mapping_info { > void *(*alloc_pgt_page)(void *); /* allocate buf for page table */ > + void (*free_pgt_page)(void *, void *); /* free buf for page table */ > void *context; /* context for alloc_pgt_page */ > unsigned long page_flag; /* page flag for PMD or PUD entry */ > unsigned long offset; /* ident mapping offset */ > @@ -16,4 +17,6 @@ struct x86_mapping_info { > int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page, > unsigned long pstart, unsigned long pend); > > +void kernel_ident_mapping_free(struct x86_mapping_info *info, pgd_t *pgd);
Maybe range-based free function can provide more flexibility (e.g., you can directly call the free function to cleanup in kernel_ident_mapping_init() internally when something goes wrong), but I guess this is sufficient for current use case (and perhaps the majority use cases). Reviewed-by: Kai Huang <[email protected]> _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
