CMA: generalize CMA reserved area management functionality
[firefly-linux-kernel-4.4.55.git] / drivers / base / dma-contiguous.c
index ad8a85bf852f911229ed13e678e7ab38b0063ba0..0411c1c57005cce63dffc71e047c5372c86da8fe 100644 (file)
 
 #include <linux/memblock.h>
 #include <linux/err.h>
-#include <linux/mm.h>
-#include <linux/mutex.h>
-#include <linux/page-isolation.h>
 #include <linux/sizes.h>
-#include <linux/slab.h>
-#include <linux/swap.h>
-#include <linux/mm_types.h>
 #include <linux/dma-contiguous.h>
-#include <linux/log2.h>
-
-struct cma {
-       unsigned long   base_pfn;
-       unsigned long   count;
-       unsigned long   *bitmap;
-       unsigned int order_per_bit; /* Order of pages represented by one bit */
-       struct mutex    lock;
-};
-
-struct cma *dma_contiguous_default_area;
+#include <linux/cma.h>
 
 #ifdef CONFIG_CMA_SIZE_MBYTES
 #define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
@@ -50,6 +34,8 @@ struct cma *dma_contiguous_default_area;
 #define CMA_SIZE_MBYTES 0
 #endif
 
+struct cma *dma_contiguous_default_area;
+
 /*
  * Default global CMA area size can be defined in kernel's .config.
  * This is useful mainly for distro maintainers to create a kernel
@@ -156,169 +142,6 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
        }
 }
 
-static DEFINE_MUTEX(cma_mutex);
-
-static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int align_order)
-{
-       return (1UL << (align_order >> cma->order_per_bit)) - 1;
-}
-
-static unsigned long cma_bitmap_maxno(struct cma *cma)
-{
-       return cma->count >> cma->order_per_bit;
-}
-
-static unsigned long cma_bitmap_pages_to_bits(struct cma *cma,
-                                               unsigned long pages)
-{
-       return ALIGN(pages, 1UL << cma->order_per_bit) >> cma->order_per_bit;
-}
-
-static void cma_clear_bitmap(struct cma *cma, unsigned long pfn, int count)
-{
-       unsigned long bitmap_no, bitmap_count;
-
-       bitmap_no = (pfn - cma->base_pfn) >> cma->order_per_bit;
-       bitmap_count = cma_bitmap_pages_to_bits(cma, count);
-
-       mutex_lock(&cma->lock);
-       bitmap_clear(cma->bitmap, bitmap_no, bitmap_count);
-       mutex_unlock(&cma->lock);
-}
-
-static int __init cma_activate_area(struct cma *cma)
-{
-       int bitmap_size = BITS_TO_LONGS(cma_bitmap_maxno(cma)) * sizeof(long);
-       unsigned long base_pfn = cma->base_pfn, pfn = base_pfn;
-       unsigned i = cma->count >> pageblock_order;
-       struct zone *zone;
-
-       cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
-
-       if (!cma->bitmap)
-               return -ENOMEM;
-
-       WARN_ON_ONCE(!pfn_valid(pfn));
-       zone = page_zone(pfn_to_page(pfn));
-
-       do {
-               unsigned j;
-               base_pfn = pfn;
-               for (j = pageblock_nr_pages; j; --j, pfn++) {
-                       WARN_ON_ONCE(!pfn_valid(pfn));
-                       /*
-                        * alloc_contig_range requires the pfn range
-                        * specified to be in the same zone. Make this
-                        * simple by forcing the entire CMA resv range
-                        * to be in the same zone.
-                        */
-                       if (page_zone(pfn_to_page(pfn)) != zone)
-                               goto err;
-               }
-               init_cma_reserved_pageblock(pfn_to_page(base_pfn));
-       } while (--i);
-
-       mutex_init(&cma->lock);
-       return 0;
-
-err:
-       kfree(cma->bitmap);
-       return -EINVAL;
-}
-
-static struct cma cma_areas[MAX_CMA_AREAS];
-static unsigned cma_area_count;
-
-static int __init cma_init_reserved_areas(void)
-{
-       int i;
-
-       for (i = 0; i < cma_area_count; i++) {
-               int ret = cma_activate_area(&cma_areas[i]);
-               if (ret)
-                       return ret;
-       }
-
-       return 0;
-}
-core_initcall(cma_init_reserved_areas);
-
-static int __init __dma_contiguous_reserve_area(phys_addr_t size,
-                       phys_addr_t base, phys_addr_t limit,
-                       phys_addr_t alignment, unsigned int order_per_bit,
-                       struct cma **res_cma, bool fixed)
-{
-       struct cma *cma = &cma_areas[cma_area_count];
-       int ret = 0;
-
-       pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n",
-               __func__, (unsigned long)size, (unsigned long)base,
-               (unsigned long)limit, (unsigned long)alignment);
-
-       if (cma_area_count == ARRAY_SIZE(cma_areas)) {
-               pr_err("Not enough slots for CMA reserved regions!\n");
-               return -ENOSPC;
-       }
-
-       if (!size)
-               return -EINVAL;
-
-       if (alignment && !is_power_of_2(alignment))
-               return -EINVAL;
-
-       /*
-        * Sanitise input arguments.
-        * Pages both ends in CMA area could be merged into adjacent unmovable
-        * migratetype page by page allocator's buddy algorithm. In the case,
-        * you couldn't get a contiguous memory, which is not what we want.
-        */
-       alignment = max(alignment,
-               (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order));
-       base = ALIGN(base, alignment);
-       size = ALIGN(size, alignment);
-       limit &= ~(alignment - 1);
-
-       /* size should be aligned with order_per_bit */
-       if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit))
-               return -EINVAL;
-
-       /* Reserve memory */
-       if (base && fixed) {
-               if (memblock_is_region_reserved(base, size) ||
-                   memblock_reserve(base, size) < 0) {
-                       ret = -EBUSY;
-                       goto err;
-               }
-       } else {
-               phys_addr_t addr = memblock_alloc_range(size, alignment, base,
-                                                       limit);
-               if (!addr) {
-                       ret = -ENOMEM;
-                       goto err;
-               } else {
-                       base = addr;
-               }
-       }
-
-       /*
-        * Each reserved area must be initialised later, when more kernel
-        * subsystems (like slab allocator) are available.
-        */
-       cma->base_pfn = PFN_DOWN(base);
-       cma->count = size >> PAGE_SHIFT;
-       cma->order_per_bit = order_per_bit;
-       *res_cma = cma;
-       cma_area_count++;
-
-       pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
-               (unsigned long)base);
-       return 0;
-
-err:
-       pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
-       return ret;
-}
-
 /**
  * dma_contiguous_reserve_area() - reserve custom contiguous area
  * @size: Size of the reserved area (in bytes),
@@ -342,77 +165,17 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
 {
        int ret;
 
-       ret = __dma_contiguous_reserve_area(size, base, limit, 0, 0,
-                                               res_cma, fixed);
+       ret = cma_declare_contiguous(size, base, limit, 0, 0, res_cma, fixed);
        if (ret)
                return ret;
 
        /* Architecture specific contiguous memory fixup. */
-       dma_contiguous_early_fixup(PFN_PHYS((*res_cma)->base_pfn),
-                               (*res_cma)->count << PAGE_SHIFT);
+       dma_contiguous_early_fixup(cma_get_base(*res_cma),
+                               cma_get_size(*res_cma));
 
        return 0;
 }
 
-static struct page *__dma_alloc_from_contiguous(struct cma *cma, int count,
-                                      unsigned int align)
-{
-       unsigned long mask, pfn, start = 0;
-       unsigned long bitmap_maxno, bitmap_no, bitmap_count;
-       struct page *page = NULL;
-       int ret;
-
-       if (!cma || !cma->count)
-               return NULL;
-
-       pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma,
-                count, align);
-
-       if (!count)
-               return NULL;
-
-       mask = cma_bitmap_aligned_mask(cma, align);
-       bitmap_maxno = cma_bitmap_maxno(cma);
-       bitmap_count = cma_bitmap_pages_to_bits(cma, count);
-
-       for (;;) {
-               mutex_lock(&cma->lock);
-               bitmap_no = bitmap_find_next_zero_area(cma->bitmap,
-                               bitmap_maxno, start, bitmap_count, mask);
-               if (bitmap_no >= bitmap_maxno) {
-                       mutex_unlock(&cma->lock);
-                       break;
-               }
-               bitmap_set(cma->bitmap, bitmap_no, bitmap_count);
-               /*
-                * It's safe to drop the lock here. We've marked this region for
-                * our exclusive use. If the migration fails we will take the
-                * lock again and unmark it.
-                */
-               mutex_unlock(&cma->lock);
-
-               pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit);
-               mutex_lock(&cma_mutex);
-               ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA);
-               mutex_unlock(&cma_mutex);
-               if (ret == 0) {
-                       page = pfn_to_page(pfn);
-                       break;
-               } else if (ret != -EBUSY) {
-                       cma_clear_bitmap(cma, pfn, count);
-                       break;
-               }
-               cma_clear_bitmap(cma, pfn, count);
-               pr_debug("%s(): memory range at %p is busy, retrying\n",
-                        __func__, pfn_to_page(pfn));
-               /* try again with a bit different memory target */
-               start = bitmap_no + mask + 1;
-       }
-
-       pr_debug("%s(): returned %p\n", __func__, page);
-       return page;
-}
-
 /**
  * dma_alloc_from_contiguous() - allocate pages from contiguous area
  * @dev:   Pointer to device for which the allocation is performed.
@@ -427,35 +190,10 @@ static struct page *__dma_alloc_from_contiguous(struct cma *cma, int count,
 struct page *dma_alloc_from_contiguous(struct device *dev, int count,
                                       unsigned int align)
 {
-       struct cma *cma = dev_get_cma_area(dev);
-
        if (align > CONFIG_CMA_ALIGNMENT)
                align = CONFIG_CMA_ALIGNMENT;
 
-       return __dma_alloc_from_contiguous(cma, count, align);
-}
-
-static bool __dma_release_from_contiguous(struct cma *cma, struct page *pages,
-                                int count)
-{
-       unsigned long pfn;
-
-       if (!cma || !pages)
-               return false;
-
-       pr_debug("%s(page %p)\n", __func__, (void *)pages);
-
-       pfn = page_to_pfn(pages);
-
-       if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count)
-               return false;
-
-       VM_BUG_ON(pfn + count > cma->base_pfn + cma->count);
-
-       free_contig_range(pfn, count);
-       cma_clear_bitmap(cma, pfn, count);
-
-       return true;
+       return cma_alloc(dev_get_cma_area(dev), count, align);
 }
 
 /**
@@ -471,7 +209,5 @@ static bool __dma_release_from_contiguous(struct cma *cma, struct page *pages,
 bool dma_release_from_contiguous(struct device *dev, struct page *pages,
                                 int count)
 {
-       struct cma *cma = dev_get_cma_area(dev);
-
-       return __dma_release_from_contiguous(cma, pages, count);
+       return cma_release(dev_get_cma_area(dev), pages, count);
 }