diff --git a/Documentation/admin-guide/mm/cma_debugfs.rst b/Documentation/admin-guide/mm/cma_debugfs.rst index 7367e6294ef6..4120e9cb0cd5 100644 --- a/Documentation/admin-guide/mm/cma_debugfs.rst +++ b/Documentation/admin-guide/mm/cma_debugfs.rst @@ -12,10 +12,16 @@ its CMA name like below: The structure of the files created under that directory is as follows: - - [RO] base_pfn: The base PFN (Page Frame Number) of the zone. + - [RO] base_pfn: The base PFN (Page Frame Number) of the CMA area. + This is the same as ranges/0/base_pfn. - [RO] count: Amount of memory in the CMA area. - [RO] order_per_bit: Order of pages represented by one bit. - - [RO] bitmap: The bitmap of page states in the zone. + - [RO] bitmap: The bitmap of allocated pages in the area. + This is the same as ranges/0/base_pfn. + - [RO] ranges/N/base_pfn: The base PFN of contiguous range N + in the CMA area. + - [RO] ranges/N/bitmap: The bit map of allocated pages in + range N in the CMA area. - [WO] alloc: Allocate N pages from that CMA area. For example:: echo 5 > /cma//alloc diff --git a/include/linux/cma.h b/include/linux/cma.h index d15b64f51336..863427c27dc2 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -40,6 +40,9 @@ static inline int __init cma_declare_contiguous(phys_addr_t base, return cma_declare_contiguous_nid(base, size, limit, alignment, order_per_bit, fixed, name, res_cma, NUMA_NO_NODE); } +extern int __init cma_declare_contiguous_multi(phys_addr_t size, + phys_addr_t align, unsigned int order_per_bit, + const char *name, struct cma **res_cma, int nid); extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, unsigned int order_per_bit, const char *name, diff --git a/mm/cma.c b/mm/cma.c index 95a8788e54d3..34caa6b29c99 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -18,6 +18,7 @@ #include #include +#include #include #include #include @@ -35,9 +36,16 @@ struct cma cma_areas[MAX_CMA_AREAS]; unsigned int cma_area_count; static DEFINE_MUTEX(cma_mutex); +static int __init __cma_declare_contiguous_nid(phys_addr_t base, + phys_addr_t size, phys_addr_t limit, + phys_addr_t alignment, unsigned int order_per_bit, + bool fixed, const char *name, struct cma **res_cma, + int nid); + phys_addr_t cma_get_base(const struct cma *cma) { - return PFN_PHYS(cma->base_pfn); + WARN_ON_ONCE(cma->nranges != 1); + return PFN_PHYS(cma->ranges[0].base_pfn); } unsigned long cma_get_size(const struct cma *cma) @@ -63,9 +71,10 @@ static unsigned long cma_bitmap_aligned_mask(const struct cma *cma, * The value returned is represented in order_per_bits. */ static unsigned long cma_bitmap_aligned_offset(const struct cma *cma, + const struct cma_memrange *cmr, unsigned int align_order) { - return (cma->base_pfn & ((1UL << align_order) - 1)) + return (cmr->base_pfn & ((1UL << align_order) - 1)) >> cma->order_per_bit; } @@ -75,46 +84,57 @@ static unsigned long cma_bitmap_pages_to_bits(const struct cma *cma, return ALIGN(pages, 1UL << cma->order_per_bit) >> cma->order_per_bit; } -static void cma_clear_bitmap(struct cma *cma, unsigned long pfn, - unsigned long count) +static void cma_clear_bitmap(struct cma *cma, const struct cma_memrange *cmr, + unsigned long pfn, unsigned long count) { unsigned long bitmap_no, bitmap_count; unsigned long flags; - bitmap_no = (pfn - cma->base_pfn) >> cma->order_per_bit; + bitmap_no = (pfn - cmr->base_pfn) >> cma->order_per_bit; bitmap_count = cma_bitmap_pages_to_bits(cma, count); spin_lock_irqsave(&cma->lock, flags); - bitmap_clear(cma->bitmap, bitmap_no, bitmap_count); + bitmap_clear(cmr->bitmap, bitmap_no, bitmap_count); cma->available_count += count; spin_unlock_irqrestore(&cma->lock, flags); } static void __init cma_activate_area(struct cma *cma) { - unsigned long base_pfn = cma->base_pfn, pfn; + unsigned long pfn, base_pfn; + int allocrange, r; struct zone *zone; + struct cma_memrange *cmr; - cma->bitmap = bitmap_zalloc(cma_bitmap_maxno(cma), GFP_KERNEL); - if (!cma->bitmap) - goto out_error; - - /* - * alloc_contig_range() requires the pfn range specified to be in the - * same zone. Simplify by forcing the entire CMA resv range to be in the - * same zone. - */ - WARN_ON_ONCE(!pfn_valid(base_pfn)); - zone = page_zone(pfn_to_page(base_pfn)); - for (pfn = base_pfn + 1; pfn < base_pfn + cma->count; pfn++) { - WARN_ON_ONCE(!pfn_valid(pfn)); - if (page_zone(pfn_to_page(pfn)) != zone) - goto not_in_zone; + for (allocrange = 0; allocrange < cma->nranges; allocrange++) { + cmr = &cma->ranges[allocrange]; + cmr->bitmap = bitmap_zalloc(cma_bitmap_maxno(cma, cmr), + GFP_KERNEL); + if (!cmr->bitmap) + goto cleanup; } - for (pfn = base_pfn; pfn < base_pfn + cma->count; - pfn += pageblock_nr_pages) - init_cma_reserved_pageblock(pfn_to_page(pfn)); + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + base_pfn = cmr->base_pfn; + + /* + * alloc_contig_range() requires the pfn range specified + * to be in the same zone. Simplify by forcing the entire + * CMA resv range to be in the same zone. + */ + WARN_ON_ONCE(!pfn_valid(base_pfn)); + zone = page_zone(pfn_to_page(base_pfn)); + for (pfn = base_pfn + 1; pfn < base_pfn + cmr->count; pfn++) { + WARN_ON_ONCE(!pfn_valid(pfn)); + if (page_zone(pfn_to_page(pfn)) != zone) + goto cleanup; + } + + for (pfn = base_pfn; pfn < base_pfn + cmr->count; + pfn += pageblock_nr_pages) + init_cma_reserved_pageblock(pfn_to_page(pfn)); + } spin_lock_init(&cma->lock); @@ -125,13 +145,19 @@ static void __init cma_activate_area(struct cma *cma) return; -not_in_zone: - bitmap_free(cma->bitmap); -out_error: +cleanup: + for (r = 0; r < allocrange; r++) + bitmap_free(cma->ranges[r].bitmap); + /* Expose all pages to the buddy, they are useless for CMA. */ if (!cma->reserve_pages_on_error) { - for (pfn = base_pfn; pfn < base_pfn + cma->count; pfn++) - free_reserved_page(pfn_to_page(pfn)); + for (r = 0; r < allocrange; r++) { + cmr = &cma->ranges[r]; + for (pfn = cmr->base_pfn; + pfn < cmr->base_pfn + cmr->count; + pfn++) + free_reserved_page(pfn_to_page(pfn)); + } } totalcma_pages -= cma->count; cma->available_count = cma->count = 0; @@ -154,6 +180,43 @@ void __init cma_reserve_pages_on_error(struct cma *cma) cma->reserve_pages_on_error = true; } +static int __init cma_new_area(const char *name, phys_addr_t size, + unsigned int order_per_bit, + struct cma **res_cma) +{ + struct cma *cma; + + if (cma_area_count == ARRAY_SIZE(cma_areas)) { + pr_err("Not enough slots for CMA reserved regions!\n"); + return -ENOSPC; + } + + /* + * Each reserved area must be initialised later, when more kernel + * subsystems (like slab allocator) are available. + */ + cma = &cma_areas[cma_area_count]; + cma_area_count++; + + if (name) + snprintf(cma->name, CMA_MAX_NAME, "%s", name); + else + snprintf(cma->name, CMA_MAX_NAME, "cma%d\n", cma_area_count); + + cma->available_count = cma->count = size >> PAGE_SHIFT; + cma->order_per_bit = order_per_bit; + *res_cma = cma; + totalcma_pages += cma->count; + + return 0; +} + +static void __init cma_drop_area(struct cma *cma) +{ + totalcma_pages -= cma->count; + cma_area_count--; +} + /** * cma_init_reserved_mem() - create custom contiguous area from reserved memory * @base: Base address of the reserved area @@ -172,13 +235,9 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, struct cma **res_cma) { struct cma *cma; + int ret; /* Sanity checks */ - if (cma_area_count == ARRAY_SIZE(cma_areas)) { - pr_err("Not enough slots for CMA reserved regions!\n"); - return -ENOSPC; - } - if (!size || !memblock_is_region_reserved(base, size)) return -EINVAL; @@ -195,27 +254,263 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, if (!IS_ALIGNED(base | size, CMA_MIN_ALIGNMENT_BYTES)) return -EINVAL; - /* - * Each reserved area must be initialised later, when more kernel - * subsystems (like slab allocator) are available. - */ - cma = &cma_areas[cma_area_count]; + ret = cma_new_area(name, size, order_per_bit, &cma); + if (ret != 0) + return ret; - if (name) - snprintf(cma->name, CMA_MAX_NAME, name); - else - snprintf(cma->name, CMA_MAX_NAME, "cma%d\n", cma_area_count); + cma->ranges[0].base_pfn = PFN_DOWN(base); + cma->ranges[0].count = cma->count; + cma->nranges = 1; - cma->base_pfn = PFN_DOWN(base); - cma->available_count = cma->count = size >> PAGE_SHIFT; - cma->order_per_bit = order_per_bit; *res_cma = cma; - cma_area_count++; - totalcma_pages += cma->count; return 0; } +/* + * Structure used while walking physical memory ranges and finding out + * which one(s) to use for a CMA area. + */ +struct cma_init_memrange { + phys_addr_t base; + phys_addr_t size; + struct list_head list; +}; + +/* + * Work array used during CMA initialization. + */ +static struct cma_init_memrange memranges[CMA_MAX_RANGES] __initdata; + +static bool __init revsizecmp(struct cma_init_memrange *mlp, + struct cma_init_memrange *mrp) +{ + return mlp->size > mrp->size; +} + +static bool __init basecmp(struct cma_init_memrange *mlp, + struct cma_init_memrange *mrp) +{ + return mlp->base < mrp->base; +} + +/* + * Helper function to create sorted lists. + */ +static void __init list_insert_sorted( + struct list_head *ranges, + struct cma_init_memrange *mrp, + bool (*cmp)(struct cma_init_memrange *lh, struct cma_init_memrange *rh)) +{ + struct list_head *mp; + struct cma_init_memrange *mlp; + + if (list_empty(ranges)) + list_add(&mrp->list, ranges); + else { + list_for_each(mp, ranges) { + mlp = list_entry(mp, struct cma_init_memrange, list); + if (cmp(mlp, mrp)) + break; + } + __list_add(&mrp->list, mlp->list.prev, &mlp->list); + } +} + +/* + * Create CMA areas with a total size of @total_size. A normal allocation + * for one area is tried first. If that fails, the biggest memblock + * ranges above 4G are selected, and allocated bottom up. + * + * The complexity here is not great, but this function will only be + * called during boot, and the lists operated on have fewer than + * CMA_MAX_RANGES elements (default value: 8). + */ +int __init cma_declare_contiguous_multi(phys_addr_t total_size, + phys_addr_t align, unsigned int order_per_bit, + const char *name, struct cma **res_cma, int nid) +{ + phys_addr_t start, end; + phys_addr_t size, sizesum, sizeleft; + struct cma_init_memrange *mrp, *mlp, *failed; + struct cma_memrange *cmrp; + LIST_HEAD(ranges); + LIST_HEAD(final_ranges); + struct list_head *mp, *next; + int ret, nr = 1; + u64 i; + struct cma *cma; + + /* + * First, try it the normal way, producing just one range. + */ + ret = __cma_declare_contiguous_nid(0, total_size, 0, align, + order_per_bit, false, name, res_cma, nid); + if (ret != -ENOMEM) + goto out; + + /* + * Couldn't find one range that fits our needs, so try multiple + * ranges. + * + * No need to do the alignment checks here, the call to + * cma_declare_contiguous_nid above would have caught + * any issues. With the checks, we know that: + * + * - @align is a power of 2 + * - @align is >= pageblock alignment + * - @size is aligned to @align and to @order_per_bit + * + * So, as long as we create ranges that have a base + * aligned to @align, and a size that is aligned to + * both @align and @order_to_bit, things will work out. + */ + nr = 0; + sizesum = 0; + failed = NULL; + + ret = cma_new_area(name, total_size, order_per_bit, &cma); + if (ret != 0) + goto out; + + align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES); + /* + * Create a list of ranges above 4G, largest range first. + */ + for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &start, &end, NULL) { + if (upper_32_bits(start) == 0) + continue; + + start = ALIGN(start, align); + if (start >= end) + continue; + + end = ALIGN_DOWN(end, align); + if (end <= start) + continue; + + size = end - start; + size = ALIGN_DOWN(size, (PAGE_SIZE << order_per_bit)); + if (!size) + continue; + sizesum += size; + + pr_debug("consider %016llx - %016llx\n", (u64)start, (u64)end); + + /* + * If we don't yet have used the maximum number of + * areas, grab a new one. + * + * If we can't use anymore, see if this range is not + * smaller than the smallest one already recorded. If + * not, re-use the smallest element. + */ + if (nr < CMA_MAX_RANGES) + mrp = &memranges[nr++]; + else { + mrp = list_last_entry(&ranges, + struct cma_init_memrange, list); + if (size < mrp->size) + continue; + list_del(&mrp->list); + sizesum -= mrp->size; + pr_debug("deleted %016llx - %016llx from the list\n", + (u64)mrp->base, (u64)mrp->base + size); + } + mrp->base = start; + mrp->size = size; + + /* + * Now do a sorted insert. + */ + list_insert_sorted(&ranges, mrp, revsizecmp); + pr_debug("added %016llx - %016llx to the list\n", + (u64)mrp->base, (u64)mrp->base + size); + pr_debug("total size now %llu\n", (u64)sizesum); + } + + /* + * There is not enough room in the CMA_MAX_RANGES largest + * ranges, so bail out. + */ + if (sizesum < total_size) { + cma_drop_area(cma); + ret = -ENOMEM; + goto out; + } + + /* + * Found ranges that provide enough combined space. + * Now, sorted them by address, smallest first, because we + * want to mimic a bottom-up memblock allocation. + */ + sizesum = 0; + list_for_each_safe(mp, next, &ranges) { + mlp = list_entry(mp, struct cma_init_memrange, list); + list_del(mp); + list_insert_sorted(&final_ranges, mlp, basecmp); + sizesum += mlp->size; + if (sizesum >= total_size) + break; + } + + /* + * Walk the final list, and add a CMA range for + * each range, possibly not using the last one fully. + */ + nr = 0; + sizeleft = total_size; + list_for_each(mp, &final_ranges) { + mlp = list_entry(mp, struct cma_init_memrange, list); + size = min(sizeleft, mlp->size); + if (memblock_reserve(mlp->base, size)) { + /* + * Unexpected error. Could go on to + * the next one, but just abort to + * be safe. + */ + failed = mlp; + break; + } + + pr_debug("created region %d: %016llx - %016llx\n", + nr, (u64)mlp->base, (u64)mlp->base + size); + cmrp = &cma->ranges[nr++]; + cmrp->base_pfn = PHYS_PFN(mlp->base); + cmrp->count = size >> PAGE_SHIFT; + + sizeleft -= size; + if (sizeleft == 0) + break; + } + + if (failed) { + list_for_each(mp, &final_ranges) { + mlp = list_entry(mp, struct cma_init_memrange, list); + if (mlp == failed) + break; + memblock_phys_free(mlp->base, mlp->size); + } + cma_drop_area(cma); + ret = -ENOMEM; + goto out; + } + + cma->nranges = nr; + *res_cma = cma; + +out: + if (ret != 0) + pr_err("Failed to reserve %lu MiB\n", + (unsigned long)total_size / SZ_1M); + else + pr_info("Reserved %lu MiB in %d range%s\n", + (unsigned long)total_size / SZ_1M, nr, + nr > 1 ? "s" : ""); + + return ret; +} + /** * cma_declare_contiguous_nid() - reserve custom contiguous area * @base: Base address of the reserved area optional, use 0 for any @@ -241,6 +536,26 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, phys_addr_t alignment, unsigned int order_per_bit, bool fixed, const char *name, struct cma **res_cma, int nid) +{ + int ret; + + ret = __cma_declare_contiguous_nid(base, size, limit, alignment, + order_per_bit, fixed, name, res_cma, nid); + if (ret != 0) + pr_err("Failed to reserve %ld MiB\n", + (unsigned long)size / SZ_1M); + else + pr_info("Reserved %ld MiB at %pa\n", + (unsigned long)size / SZ_1M, &base); + + return ret; +} + +static int __init __cma_declare_contiguous_nid(phys_addr_t base, + phys_addr_t size, phys_addr_t limit, + phys_addr_t alignment, unsigned int order_per_bit, + bool fixed, const char *name, struct cma **res_cma, + int nid) { phys_addr_t memblock_end = memblock_end_of_DRAM(); phys_addr_t highmem_start; @@ -273,10 +588,9 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, /* Sanitise input arguments. */ alignment = max_t(phys_addr_t, alignment, CMA_MIN_ALIGNMENT_BYTES); if (fixed && base & (alignment - 1)) { - ret = -EINVAL; pr_err("Region at %pa must be aligned to %pa bytes\n", &base, &alignment); - goto err; + return -EINVAL; } base = ALIGN(base, alignment); size = ALIGN(size, alignment); @@ -294,10 +608,9 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, * low/high memory boundary. */ if (fixed && base < highmem_start && base + size > highmem_start) { - ret = -EINVAL; pr_err("Region at %pa defined on low/high memory boundary (%pa)\n", &base, &highmem_start); - goto err; + return -EINVAL; } /* @@ -309,18 +622,16 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, limit = memblock_end; if (base + size > limit) { - ret = -EINVAL; pr_err("Size (%pa) of region at %pa exceeds limit (%pa)\n", &size, &base, &limit); - goto err; + return -EINVAL; } /* Reserve memory */ if (fixed) { if (memblock_is_region_reserved(base, size) || memblock_reserve(base, size) < 0) { - ret = -EBUSY; - goto err; + return -EBUSY; } } else { phys_addr_t addr = 0; @@ -357,10 +668,8 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, if (!addr) { addr = memblock_alloc_range_nid(size, alignment, base, limit, nid, true); - if (!addr) { - ret = -ENOMEM; - goto err; - } + if (!addr) + return -ENOMEM; } /* @@ -373,75 +682,67 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, ret = cma_init_reserved_mem(base, size, order_per_bit, name, res_cma); if (ret) - goto free_mem; + memblock_phys_free(base, size); - pr_info("Reserved %ld MiB at %pa on node %d\n", (unsigned long)size / SZ_1M, - &base, nid); - return 0; - -free_mem: - memblock_phys_free(base, size); -err: - pr_err("Failed to reserve %ld MiB on node %d\n", (unsigned long)size / SZ_1M, - nid); return ret; } static void cma_debug_show_areas(struct cma *cma) { unsigned long next_zero_bit, next_set_bit, nr_zero; - unsigned long start = 0; + unsigned long start; unsigned long nr_part; - unsigned long nbits = cma_bitmap_maxno(cma); + unsigned long nbits; + int r; + struct cma_memrange *cmr; spin_lock_irq(&cma->lock); pr_info("number of available pages: "); - for (;;) { - next_zero_bit = find_next_zero_bit(cma->bitmap, nbits, start); - if (next_zero_bit >= nbits) - break; - next_set_bit = find_next_bit(cma->bitmap, nbits, next_zero_bit); - nr_zero = next_set_bit - next_zero_bit; - nr_part = nr_zero << cma->order_per_bit; - pr_cont("%s%lu@%lu", start ? "+" : "", nr_part, - next_zero_bit); - start = next_zero_bit + nr_zero; + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + + start = 0; + nbits = cma_bitmap_maxno(cma, cmr); + + pr_info("range %d: ", r); + for (;;) { + next_zero_bit = find_next_zero_bit(cmr->bitmap, + nbits, start); + if (next_zero_bit >= nbits) + break; + next_set_bit = find_next_bit(cmr->bitmap, nbits, + next_zero_bit); + nr_zero = next_set_bit - next_zero_bit; + nr_part = nr_zero << cma->order_per_bit; + pr_cont("%s%lu@%lu", start ? "+" : "", nr_part, + next_zero_bit); + start = next_zero_bit + nr_zero; + } + pr_info("\n"); } pr_cont("=> %lu free of %lu total pages\n", cma->available_count, cma->count); spin_unlock_irq(&cma->lock); } -static struct page *__cma_alloc(struct cma *cma, unsigned long count, - unsigned int align, gfp_t gfp) +static int cma_range_alloc(struct cma *cma, struct cma_memrange *cmr, + unsigned long count, unsigned int align, + struct page **pagep, gfp_t gfp) { unsigned long mask, offset; unsigned long pfn = -1; unsigned long start = 0; unsigned long bitmap_maxno, bitmap_no, bitmap_count; - unsigned long i; + int ret = -EBUSY; struct page *page = NULL; - int ret = -ENOMEM; - const char *name = cma ? cma->name : NULL; - - trace_cma_alloc_start(name, count, align); - - if (!cma || !cma->count || !cma->bitmap) - return page; - - pr_debug("%s(cma %p, name: %s, count %lu, align %d)\n", __func__, - (void *)cma, cma->name, count, align); - - if (!count) - return page; mask = cma_bitmap_aligned_mask(cma, align); - offset = cma_bitmap_aligned_offset(cma, align); - bitmap_maxno = cma_bitmap_maxno(cma); + offset = cma_bitmap_aligned_offset(cma, cmr, align); + bitmap_maxno = cma_bitmap_maxno(cma, cmr); bitmap_count = cma_bitmap_pages_to_bits(cma, count); if (bitmap_count > bitmap_maxno) - return page; + goto out; for (;;) { spin_lock_irq(&cma->lock); @@ -453,14 +754,14 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, spin_unlock_irq(&cma->lock); break; } - bitmap_no = bitmap_find_next_zero_area_off(cma->bitmap, + bitmap_no = bitmap_find_next_zero_area_off(cmr->bitmap, bitmap_maxno, start, bitmap_count, mask, offset); if (bitmap_no >= bitmap_maxno) { spin_unlock_irq(&cma->lock); break; } - bitmap_set(cma->bitmap, bitmap_no, bitmap_count); + bitmap_set(cmr->bitmap, bitmap_no, bitmap_count); cma->available_count -= count; /* * It's safe to drop the lock here. We've marked this region for @@ -469,7 +770,7 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, */ spin_unlock_irq(&cma->lock); - pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); + pfn = cmr->base_pfn + (bitmap_no << cma->order_per_bit); mutex_lock(&cma_mutex); ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp); mutex_unlock(&cma_mutex); @@ -478,7 +779,7 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, break; } - cma_clear_bitmap(cma, pfn, count); + cma_clear_bitmap(cma, cmr, pfn, count); if (ret != -EBUSY) break; @@ -490,6 +791,38 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, /* try again with a bit different memory target */ start = bitmap_no + mask + 1; } +out: + *pagep = page; + return ret; +} + +static struct page *__cma_alloc(struct cma *cma, unsigned long count, + unsigned int align, gfp_t gfp) +{ + struct page *page = NULL; + int ret = -ENOMEM, r; + unsigned long i; + const char *name = cma ? cma->name : NULL; + + trace_cma_alloc_start(name, count, align); + + if (!cma || !cma->count) + return page; + + pr_debug("%s(cma %p, name: %s, count %lu, align %d)\n", __func__, + (void *)cma, cma->name, count, align); + + if (!count) + return page; + + for (r = 0; r < cma->nranges; r++) { + page = NULL; + + ret = cma_range_alloc(cma, &cma->ranges[r], count, align, + &page, gfp); + if (ret != -EBUSY || page) + break; + } /* * CMA can allocate multiple page blocks, which results in different @@ -508,7 +841,8 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, } pr_debug("%s(): returned %p\n", __func__, page); - trace_cma_alloc_finish(name, pfn, page, count, align, ret); + trace_cma_alloc_finish(name, page ? page_to_pfn(page) : 0, + page, count, align, ret); if (page) { count_vm_event(CMA_ALLOC_SUCCESS); cma_sysfs_account_success_pages(cma, count); @@ -551,20 +885,31 @@ struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp) bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned long count) { - unsigned long pfn; + unsigned long pfn, end; + int r; + struct cma_memrange *cmr; + bool ret; - if (!cma || !pages) + if (!cma || !pages || count > cma->count) return false; pfn = page_to_pfn(pages); + ret = false; - if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) { - pr_debug("%s(page %p, count %lu)\n", __func__, - (void *)pages, count); - return false; + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + end = cmr->base_pfn + cmr->count; + if (pfn >= cmr->base_pfn && pfn < end) { + ret = pfn + count <= end; + break; + } } - return true; + if (!ret) + pr_debug("%s(page %p, count %lu)\n", + __func__, (void *)pages, count); + + return ret; } /** @@ -580,19 +925,32 @@ bool cma_pages_valid(struct cma *cma, const struct page *pages, bool cma_release(struct cma *cma, const struct page *pages, unsigned long count) { - unsigned long pfn; + struct cma_memrange *cmr; + unsigned long pfn, end_pfn; + int r; + + pr_debug("%s(page %p, count %lu)\n", __func__, (void *)pages, count); if (!cma_pages_valid(cma, pages, count)) return false; - pr_debug("%s(page %p, count %lu)\n", __func__, (void *)pages, count); - pfn = page_to_pfn(pages); + end_pfn = pfn + count; - VM_BUG_ON(pfn + count > cma->base_pfn + cma->count); + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + if (pfn >= cmr->base_pfn && + pfn < (cmr->base_pfn + cmr->count)) { + VM_BUG_ON(end_pfn > cmr->base_pfn + cmr->count); + break; + } + } + + if (r == cma->nranges) + return false; free_contig_range(pfn, count); - cma_clear_bitmap(cma, pfn, count); + cma_clear_bitmap(cma, cmr, pfn, count); cma_sysfs_account_release_pages(cma, count); trace_cma_release(cma->name, pfn, pages, count); diff --git a/mm/cma.h b/mm/cma.h index 3dd3376ae980..5f39dd1aac91 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -10,19 +10,35 @@ struct cma_kobject { struct cma *cma; }; +/* + * Multi-range support. This can be useful if the size of the allocation + * is not expected to be larger than the alignment (like with hugetlb_cma), + * 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. + */ +struct cma_memrange { + unsigned long base_pfn; + unsigned long count; + unsigned long *bitmap; +#ifdef CONFIG_CMA_DEBUGFS + struct debugfs_u32_array dfs_bitmap; +#endif +}; +#define CMA_MAX_RANGES 8 + struct cma { - unsigned long base_pfn; unsigned long count; unsigned long available_count; - unsigned long *bitmap; unsigned int order_per_bit; /* Order of pages represented by one bit */ spinlock_t lock; #ifdef CONFIG_CMA_DEBUGFS struct hlist_head mem_head; spinlock_t mem_head_lock; - struct debugfs_u32_array dfs_bitmap; #endif char name[CMA_MAX_NAME]; + int nranges; + struct cma_memrange ranges[CMA_MAX_RANGES]; #ifdef CONFIG_CMA_SYSFS /* the number of CMA page successful allocations */ atomic64_t nr_pages_succeeded; @@ -39,9 +55,10 @@ struct cma { extern struct cma cma_areas[MAX_CMA_AREAS]; extern unsigned int cma_area_count; -static inline unsigned long cma_bitmap_maxno(struct cma *cma) +static inline unsigned long cma_bitmap_maxno(struct cma *cma, + struct cma_memrange *cmr) { - return cma->count >> cma->order_per_bit; + return cmr->count >> cma->order_per_bit; } #ifdef CONFIG_CMA_SYSFS diff --git a/mm/cma_debug.c b/mm/cma_debug.c index 89236f22230a..fdf899532ca0 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -46,17 +46,26 @@ DEFINE_DEBUGFS_ATTRIBUTE(cma_used_fops, cma_used_get, NULL, "%llu\n"); static int cma_maxchunk_get(void *data, u64 *val) { struct cma *cma = data; + struct cma_memrange *cmr; unsigned long maxchunk = 0; - unsigned long start, end = 0; - unsigned long bitmap_maxno = cma_bitmap_maxno(cma); + unsigned long start, end; + unsigned long bitmap_maxno; + int r; spin_lock_irq(&cma->lock); - for (;;) { - start = find_next_zero_bit(cma->bitmap, bitmap_maxno, end); - if (start >= bitmap_maxno) - break; - end = find_next_bit(cma->bitmap, bitmap_maxno, start); - maxchunk = max(end - start, maxchunk); + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + bitmap_maxno = cma_bitmap_maxno(cma, cmr); + end = 0; + for (;;) { + start = find_next_zero_bit(cmr->bitmap, + bitmap_maxno, end); + if (start >= bitmap_maxno) + break; + end = find_next_bit(cmr->bitmap, bitmap_maxno, + start); + maxchunk = max(end - start, maxchunk); + } } spin_unlock_irq(&cma->lock); *val = (u64)maxchunk << cma->order_per_bit; @@ -159,24 +168,41 @@ DEFINE_DEBUGFS_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n"); static void cma_debugfs_add_one(struct cma *cma, struct dentry *root_dentry) { - struct dentry *tmp; + struct dentry *tmp, *dir, *rangedir; + int r; + char rdirname[12]; + struct cma_memrange *cmr; tmp = debugfs_create_dir(cma->name, root_dentry); debugfs_create_file("alloc", 0200, tmp, cma, &cma_alloc_fops); debugfs_create_file("free", 0200, tmp, cma, &cma_free_fops); - debugfs_create_file("base_pfn", 0444, tmp, - &cma->base_pfn, &cma_debugfs_fops); debugfs_create_file("count", 0444, tmp, &cma->count, &cma_debugfs_fops); debugfs_create_file("order_per_bit", 0444, tmp, &cma->order_per_bit, &cma_debugfs_fops); debugfs_create_file("used", 0444, tmp, cma, &cma_used_fops); debugfs_create_file("maxchunk", 0444, tmp, cma, &cma_maxchunk_fops); - cma->dfs_bitmap.array = (u32 *)cma->bitmap; - cma->dfs_bitmap.n_elements = DIV_ROUND_UP(cma_bitmap_maxno(cma), - BITS_PER_BYTE * sizeof(u32)); - debugfs_create_u32_array("bitmap", 0444, tmp, &cma->dfs_bitmap); + rangedir = debugfs_create_dir("ranges", tmp); + for (r = 0; r < cma->nranges; r++) { + cmr = &cma->ranges[r]; + snprintf(rdirname, sizeof(rdirname), "%d", r); + dir = debugfs_create_dir(rdirname, rangedir); + debugfs_create_file("base_pfn", 0444, dir, + &cmr->base_pfn, &cma_debugfs_fops); + cmr->dfs_bitmap.array = (u32 *)cmr->bitmap; + cmr->dfs_bitmap.n_elements = + DIV_ROUND_UP(cma_bitmap_maxno(cma, cmr), + BITS_PER_BYTE * sizeof(u32)); + debugfs_create_u32_array("bitmap", 0444, dir, + &cmr->dfs_bitmap); + } + + /* + * Backward compatible symlinks to range 0 for base_pfn and bitmap. + */ + debugfs_create_symlink("base_pfn", tmp, "ranges/0/base_pfn"); + debugfs_create_symlink("bitmap", tmp, "ranges/0/bitmap"); } static int __init cma_debugfs_init(void)