diff --git a/mm/cma.c b/mm/cma.c index 5e1d169e24fa..09322b8284bd 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -144,9 +144,10 @@ bool cma_validate_zones(struct cma *cma) static void __init cma_activate_area(struct cma *cma) { - unsigned long pfn, base_pfn; + unsigned long pfn, end_pfn; int allocrange, r; struct cma_memrange *cmr; + unsigned long bitmap_count, count; for (allocrange = 0; allocrange < cma->nranges; allocrange++) { cmr = &cma->ranges[allocrange]; @@ -161,8 +162,13 @@ static void __init cma_activate_area(struct cma *cma) for (r = 0; r < cma->nranges; r++) { cmr = &cma->ranges[r]; - base_pfn = cmr->base_pfn; - for (pfn = base_pfn; pfn < base_pfn + cmr->count; + if (cmr->early_pfn != cmr->base_pfn) { + count = cmr->early_pfn - cmr->base_pfn; + bitmap_count = cma_bitmap_pages_to_bits(cma, count); + bitmap_set(cmr->bitmap, 0, bitmap_count); + } + + for (pfn = cmr->early_pfn; pfn < cmr->base_pfn + cmr->count; pfn += pageblock_nr_pages) init_cma_reserved_pageblock(pfn_to_page(pfn)); } @@ -173,6 +179,7 @@ static void __init cma_activate_area(struct cma *cma) INIT_HLIST_HEAD(&cma->mem_head); spin_lock_init(&cma->mem_head_lock); #endif + set_bit(CMA_ACTIVATED, &cma->flags); return; @@ -184,9 +191,8 @@ static void __init cma_activate_area(struct cma *cma) if (!test_bit(CMA_RESERVE_PAGES_ON_ERROR, &cma->flags)) { for (r = 0; r < allocrange; r++) { cmr = &cma->ranges[r]; - for (pfn = cmr->base_pfn; - pfn < cmr->base_pfn + cmr->count; - pfn++) + end_pfn = cmr->base_pfn + cmr->count; + for (pfn = cmr->early_pfn; pfn < end_pfn; pfn++) free_reserved_page(pfn_to_page(pfn)); } } @@ -290,6 +296,7 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, return ret; cma->ranges[0].base_pfn = PFN_DOWN(base); + cma->ranges[0].early_pfn = PFN_DOWN(base); cma->ranges[0].count = cma->count; cma->nranges = 1; cma->nid = NUMA_NO_NODE; @@ -509,6 +516,7 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size, nr, (u64)mlp->base, (u64)mlp->base + size); cmrp = &cma->ranges[nr++]; cmrp->base_pfn = PHYS_PFN(mlp->base); + cmrp->early_pfn = cmrp->base_pfn; cmrp->count = size >> PAGE_SHIFT; sizeleft -= size; @@ -540,7 +548,6 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size, pr_info("Reserved %lu MiB in %d range%s\n", (unsigned long)total_size / SZ_1M, nr, nr > 1 ? "s" : ""); - return ret; } @@ -1034,3 +1041,65 @@ bool cma_intersects(struct cma *cma, unsigned long start, unsigned long end) return false; } + +/* + * Very basic function to reserve memory from a CMA area that has not + * yet been activated. This is expected to be called early, when the + * system is single-threaded, so there is no locking. The alignment + * checking is restrictive - only pageblock-aligned areas + * (CMA_MIN_ALIGNMENT_BYTES) may be reserved through this function. + * This keeps things simple, and is enough for the current use case. + * + * The CMA bitmaps have not yet been allocated, so just start + * reserving from the bottom up, using a PFN to keep track + * of what has been reserved. Unreserving is not possible. + * + * The caller is responsible for initializing the page structures + * in the area properly, since this just points to memblock-allocated + * memory. The caller should subsequently use init_cma_pageblock to + * set the migrate type and CMA stats the pageblocks that were reserved. + * + * If the CMA area fails to activate later, memory obtained through + * this interface is not handed to the page allocator, this is + * the responsibility of the caller (e.g. like normal memblock-allocated + * memory). + */ +void __init *cma_reserve_early(struct cma *cma, unsigned long size) +{ + int r; + struct cma_memrange *cmr; + unsigned long available; + void *ret = NULL; + + if (!cma || !cma->count) + return NULL; + /* + * Can only be called early in init. + */ + if (test_bit(CMA_ACTIVATED, &cma->flags)) + return NULL; + + if (!IS_ALIGNED(size, CMA_MIN_ALIGNMENT_BYTES)) + return NULL; + + if (!IS_ALIGNED(size, (PAGE_SIZE << cma->order_per_bit))) + return NULL; + + size >>= PAGE_SHIFT; + + if (size > cma->available_count) + return NULL; + + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + available = cmr->count - (cmr->early_pfn - cmr->base_pfn); + if (size <= available) { + ret = phys_to_virt(PFN_PHYS(cmr->early_pfn)); + cmr->early_pfn += size; + cma->available_count -= size; + return ret; + } + } + + return ret; +} diff --git a/mm/cma.h b/mm/cma.h index bddc84b3cd96..df7fc623b7a6 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -16,9 +16,16 @@ struct cma_kobject { * and the total amount of memory requested, while smaller than the total * amount of memory available, is large enough that it doesn't fit in a * single physical memory range because of memory holes. + * + * Fields: + * @base_pfn: physical address of range + * @early_pfn: first PFN not reserved through cma_reserve_early + * @count: size of range + * @bitmap: bitmap of allocated (1 << order_per_bit)-sized chunks. */ struct cma_memrange { unsigned long base_pfn; + unsigned long early_pfn; unsigned long count; unsigned long *bitmap; #ifdef CONFIG_CMA_DEBUGFS @@ -58,6 +65,7 @@ enum cma_flags { CMA_RESERVE_PAGES_ON_ERROR, CMA_ZONES_VALID, CMA_ZONES_INVALID, + CMA_ACTIVATED, }; extern struct cma cma_areas[MAX_CMA_AREAS]; diff --git a/mm/internal.h b/mm/internal.h index 8233c207d3f3..31c626130883 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -848,6 +848,22 @@ void init_cma_reserved_pageblock(struct page *page); #endif /* CONFIG_COMPACTION || CONFIG_CMA */ +struct cma; + +#ifdef CONFIG_CMA +void *cma_reserve_early(struct cma *cma, unsigned long size); +void init_cma_pageblock(struct page *page); +#else +static inline void *cma_reserve_early(struct cma *cma, unsigned long size) +{ + return NULL; +} +static inline void init_cma_pageblock(struct page *page) +{ +} +#endif + + int find_suitable_fallback(struct free_area *area, unsigned int order, int migratetype, bool only_stealable, bool *can_steal); diff --git a/mm/mm_init.c b/mm/mm_init.c index 3eec528afe43..b5047c5ef7d6 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2263,6 +2263,15 @@ void __init init_cma_reserved_pageblock(struct page *page) adjust_managed_page_count(page, pageblock_nr_pages); page_zone(page)->cma_pages += pageblock_nr_pages; } +/* + * Similar to above, but only set the migrate type and stats. + */ +void __init init_cma_pageblock(struct page *page) +{ + set_pageblock_migratetype(page, MIGRATE_CMA); + adjust_managed_page_count(page, pageblock_nr_pages); + page_zone(page)->cma_pages += pageblock_nr_pages; +} #endif void set_zone_contiguous(struct zone *zone)