Hi Mike, On Tue, 18 Feb 2025 09:24:53 +0200 Mike Rapoport <[email protected]> wrote:
> Hi Masami, > > On Tue, Feb 11, 2025 at 11:47:03PM +0900, Masami Hiramatsu (Google) wrote: > > From: Masami Hiramatsu (Google) <[email protected]> > > > > Add reserve_mem_release_by_name() to release a reserved memory region > > with a given name. This allows us to release reserved memory which is > > defined by kernel cmdline, after boot. > > > > Signed-off-by: Masami Hiramatsu (Google) <[email protected]> > > Cc: Andrew Morton <[email protected]> > > Cc: Mike Rapoport <[email protected]> > > Cc: [email protected] > > ... > > > +/** > > + * reserve_mem_release_by_name - Release reserved memory region with a > > given name > > + * @name: The name that is attatched to a reserved memory region > > + * > > + * Forcibly release the pages in the reserved memory region so that those > > memory > > + * can be used as free memory. After released the reserved region size > > becomes 0. > > + * > > + * Returns: 1 if released or 0 if not found. > > + */ > > +int reserve_mem_release_by_name(const char *name) > > +{ > > + struct reserve_mem_table *map; > > + unsigned int page_count; > > + phys_addr_t start; > > + > > + guard(mutex)(&reserve_mem_lock); > > + map = reserve_mem_find_by_name_nolock(name); > > + if (!map) > > + return 0; > > + > > + start = map->start; > > + page_count = DIV_ROUND_UP(map->size, PAGE_SIZE); > > + > > + for (int i = 0; i < page_count; i++) { > > + phys_addr_t addr = start + i * PAGE_SIZE; > > + struct page *page = pfn_to_page(addr >> PAGE_SHIFT); > > + > > + page->flags &= ~BIT(PG_reserved); > > + __free_page(page); > > + } > > We have free_reserved_area(), please use it here. > Otherwise > > Acked-by: Mike Rapoport (Microsoft) <[email protected]> Thanks! but I can not use free_reserved_area() here because it uses virt_to_page(). Here we only know the physical address in the map. I think we can use free_reserved_page() instead. Is that OK? Thank you, > > > + map->size = 0; > > + > > + return 1; > > +} > > + > > /* > > * Parse reserve_mem=nn:align:name > > */ > > > > -- > Sincerely yours, > Mike. -- Masami Hiramatsu (Google) <[email protected]>
