From 95a2ac937013cc3aaaea02abcdd167b96874548d Mon Sep 17 00:00:00 2001 From: Sumanth Korikkar Date: Mon, 20 Nov 2023 15:53:54 +0100 Subject: mm: use vmem_altmap code without CONFIG_ZONE_DEVICE vmem_altmap_free() and vmem_altmap_offset() could be utlized without CONFIG_ZONE_DEVICE enabled. For example, mm/memory_hotplug.c:__add_pages() relies on that. The altmap is no longer restricted to ZONE_DEVICE handling, but instead depends on CONFIG_SPARSEMEM_VMEMMAP. When CONFIG_SPARSEMEM_VMEMMAP is disabled, these functions are defined as inline stubs, ensuring compatibility with configurations that do not use sparsemem vmemmap. Without it, lkp reported the following: ld: arch/x86/mm/init_64.o: in function `remove_pagetable': init_64.c:(.meminit.text+0xfc7): undefined reference to `vmem_altmap_free' Link: https://lkml.kernel.org/r/20231120145354.308999-4-sumanthk@linux.ibm.com Signed-off-by: Sumanth Korikkar Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202311180545.VeyRXEDq-lkp@intel.com/ Reviewed-by: Gerald Schaefer Acked-by: David Hildenbrand Cc: Alexander Gordeev Cc: Aneesh Kumar K.V Cc: Anshuman Khandual Cc: Heiko Carstens Cc: Michal Hocko Cc: Oscar Salvador Cc: Vasily Gorbik Signed-off-by: Andrew Morton --- include/linux/memremap.h | 12 ------------ include/linux/mm.h | 26 ++++++++++++++++++++++++++ 2 files changed, 26 insertions(+), 12 deletions(-) (limited to 'include') diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 1314d9c5f05b..744c830f4b13 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -196,8 +196,6 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, struct dev_pagemap *pgmap); bool pgmap_pfn_valid(struct dev_pagemap *pgmap, unsigned long pfn); -unsigned long vmem_altmap_offset(struct vmem_altmap *altmap); -void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns); unsigned long memremap_compat_align(void); #else static inline void *devm_memremap_pages(struct device *dev, @@ -228,16 +226,6 @@ static inline bool pgmap_pfn_valid(struct dev_pagemap *pgmap, unsigned long pfn) return false; } -static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) -{ - return 0; -} - -static inline void vmem_altmap_free(struct vmem_altmap *altmap, - unsigned long nr_pfns) -{ -} - /* when memremap_pages() is disabled all archs can remap a single page */ static inline unsigned long memremap_compat_align(void) { diff --git a/include/linux/mm.h b/include/linux/mm.h index 13a090271716..a422cc123a2d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3871,6 +3871,32 @@ void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap); #endif +#ifdef CONFIG_SPARSEMEM_VMEMMAP +static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) +{ + /* number of pfns from base where pfn_to_page() is valid */ + if (altmap) + return altmap->reserve + altmap->free; + return 0; +} + +static inline void vmem_altmap_free(struct vmem_altmap *altmap, + unsigned long nr_pfns) +{ + altmap->alloc -= nr_pfns; +} +#else +static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) +{ + return 0; +} + +static inline void vmem_altmap_free(struct vmem_altmap *altmap, + unsigned long nr_pfns) +{ +} +#endif + #define VMEMMAP_RESERVE_NR 2 #ifdef CONFIG_ARCH_WANT_OPTIMIZE_DAX_VMEMMAP static inline bool __vmemmap_can_optimize(struct vmem_altmap *altmap, -- cgit v1.2.3-70-g09d2