#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>
-
-struct cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
-};
-
-struct cma *dma_contiguous_default_area;
+#include <linux/cma.h>
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
#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 usefull mainly for distro maintainers to create a kernel
+ * This is useful mainly for distro maintainers to create a kernel
* that works correctly for most supported systems.
* The size can be set in bytes or as a percentage of the total memory
* in the system.
* Users, who want to set the size of global CMA area for their system
* should use cma= kernel parameter.
*/
-static const phys_addr_t size_bytes = CMA_SIZE_MBYTES * SZ_1M;
+static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
static phys_addr_t size_cmdline = -1;
+static phys_addr_t base_cmdline;
+static phys_addr_t limit_cmdline;
static int __init early_cma(char *p)
{
pr_debug("%s(%s)\n", __func__, p);
size_cmdline = memparse(p, &p);
+ if (*p != '@')
+ return 0;
+ base_cmdline = memparse(p + 1, &p);
+ if (*p != '-') {
+ limit_cmdline = base_cmdline + size_cmdline;
+ return 0;
+ }
+ limit_cmdline = memparse(p + 1, &p);
+
return 0;
}
early_param("cma", early_cma);
#endif
/**
- * dma_contiguous_reserve() - reserve area for contiguous memory handling
+ * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling
* @limit: End address of the reserved memory (optional, 0 for any).
*
* This function reserves memory from early allocator. It should be
void __init dma_contiguous_reserve(phys_addr_t limit)
{
phys_addr_t selected_size = 0;
+ phys_addr_t selected_base = 0;
+ phys_addr_t selected_limit = limit;
+ bool fixed = false;
pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);
if (size_cmdline != -1) {
selected_size = size_cmdline;
+ selected_base = base_cmdline;
+ selected_limit = min_not_zero(limit_cmdline, limit);
+ if (base_cmdline + size_cmdline == limit_cmdline)
+ fixed = true;
} else {
#ifdef CONFIG_CMA_SIZE_SEL_MBYTES
selected_size = size_bytes;
#endif
}
- if (selected_size) {
+ if (selected_size && !dma_contiguous_default_area) {
pr_debug("%s: reserving %ld MiB for global area\n", __func__,
(unsigned long)selected_size / SZ_1M);
- dma_declare_contiguous(NULL, selected_size, 0, limit);
- }
-};
-
-static DEFINE_MUTEX(cma_mutex);
-
-static __init int cma_activate_area(unsigned long base_pfn, unsigned long count)
-{
- unsigned long pfn = base_pfn;
- unsigned i = count >> pageblock_order;
- struct zone *zone;
-
- 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));
- if (page_zone(pfn_to_page(pfn)) != zone)
- return -EINVAL;
- }
- init_cma_reserved_pageblock(pfn_to_page(base_pfn));
- } while (--i);
- return 0;
-}
-
-static __init struct cma *cma_create_area(unsigned long base_pfn,
- unsigned long count)
-{
- int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
- struct cma *cma;
- int ret = -ENOMEM;
-
- pr_debug("%s(base %08lx, count %lx)\n", __func__, base_pfn, count);
-
- cma = kmalloc(sizeof *cma, GFP_KERNEL);
- if (!cma)
- return ERR_PTR(-ENOMEM);
-
- cma->base_pfn = base_pfn;
- cma->count = count;
- cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
-
- if (!cma->bitmap)
- goto no_mem;
-
- ret = cma_activate_area(base_pfn, count);
- if (ret)
- goto error;
-
- pr_debug("%s: returned %p\n", __func__, (void *)cma);
- return cma;
-
-error:
- kfree(cma->bitmap);
-no_mem:
- kfree(cma);
- return ERR_PTR(ret);
-}
-
-static struct cma_reserved {
- phys_addr_t start;
- unsigned long size;
- struct device *dev;
-} cma_reserved[MAX_CMA_AREAS] __initdata;
-static unsigned cma_reserved_count __initdata;
-
-static int __init cma_init_reserved_areas(void)
-{
- struct cma_reserved *r = cma_reserved;
- unsigned i = cma_reserved_count;
-
- pr_debug("%s()\n", __func__);
-
- for (; i; --i, ++r) {
- struct cma *cma;
- cma = cma_create_area(PFN_DOWN(r->start),
- r->size >> PAGE_SHIFT);
- if (!IS_ERR(cma))
- dev_set_cma_area(r->dev, cma);
+ dma_contiguous_reserve_area(selected_size, selected_base,
+ selected_limit,
+ &dma_contiguous_default_area,
+ fixed);
}
- return 0;
}
-core_initcall(cma_init_reserved_areas);
/**
- * dma_declare_contiguous() - reserve area for contiguous memory handling
- * for particular device
- * @dev: Pointer to device structure.
- * @size: Size of the reserved memory.
- * @base: Start address of the reserved memory (optional, 0 for any).
+ * dma_contiguous_reserve_area() - reserve custom contiguous area
+ * @size: Size of the reserved area (in bytes),
+ * @base: Base address of the reserved area optional, use 0 for any
* @limit: End address of the reserved memory (optional, 0 for any).
+ * @res_cma: Pointer to store the created cma region.
+ * @fixed: hint about where to place the reserved area
+ *
+ * This function reserves memory from early allocator. It should be
+ * called by arch specific code once the early allocator (memblock or bootmem)
+ * has been activated and all other subsystems have already allocated/reserved
+ * memory. This function allows to create custom reserved areas for specific
+ * devices.
*
- * This function reserves memory for specified device. It should be
- * called by board specific code when early allocator (memblock or bootmem)
- * is still activate.
+ * If @fixed is true, reserve contiguous area at exactly @base. If false,
+ * reserve in range from @base to @limit.
*/
-int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
- phys_addr_t base, phys_addr_t limit)
+int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+ phys_addr_t limit, struct cma **res_cma,
+ bool fixed)
{
- struct cma_reserved *r = &cma_reserved[cma_reserved_count];
- phys_addr_t alignment;
-
- pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__,
- (unsigned long)size, (unsigned long)base,
- (unsigned long)limit);
-
- /* Sanity checks */
- if (cma_reserved_count == ARRAY_SIZE(cma_reserved)) {
- pr_err("Not enough slots for CMA reserved regions!\n");
- return -ENOSPC;
- }
-
- if (!size)
- return -EINVAL;
-
- /* Sanitise input arguments */
- alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
- base = ALIGN(base, alignment);
- size = ALIGN(size, alignment);
- limit &= ~(alignment - 1);
-
- /* Reserve memory */
- if (base) {
- if (memblock_is_region_reserved(base, size) ||
- memblock_reserve(base, size) < 0) {
- base = -EBUSY;
- goto err;
- }
- } else {
- /*
- * Use __memblock_alloc_base() since
- * memblock_alloc_base() panic()s.
- */
- phys_addr_t addr = __memblock_alloc_base(size, alignment, limit);
- if (!addr) {
- base = -ENOMEM;
- goto err;
- } else {
- base = addr;
- }
- }
+ int ret;
- /*
- * Each reserved area must be initialised later, when more kernel
- * subsystems (like slab allocator) are available.
- */
- r->start = base;
- r->size = size;
- r->dev = dev;
- cma_reserved_count++;
- pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
- (unsigned long)base);
+ ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed, res_cma);
+ if (ret)
+ return ret;
/* Architecture specific contiguous memory fixup. */
- dma_contiguous_early_fixup(base, size);
+ dma_contiguous_early_fixup(cma_get_base(*res_cma),
+ cma_get_size(*res_cma));
+
return 0;
-err:
- pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
- return base;
}
/**
*
* This function allocates memory buffer for specified device. It uses
* device specific contiguous memory area if available or the default
- * global one. Requires architecture specific get_dev_cma_area() helper
+ * global one. Requires architecture specific dev_get_cma_area() helper
* function.
*/
-struct page *dma_alloc_from_contiguous(struct device *dev, int count,
+struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
unsigned int align)
{
- unsigned long mask, pfn, pageno, start = 0;
- struct cma *cma = dev_get_cma_area(dev);
- struct page *page = NULL;
- int ret;
-
- if (!cma || !cma->count)
- return NULL;
-
if (align > CONFIG_CMA_ALIGNMENT)
align = CONFIG_CMA_ALIGNMENT;
- pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma,
- count, align);
-
- if (!count)
- return NULL;
-
- mask = (1 << align) - 1;
-
- mutex_lock(&cma_mutex);
-
- for (;;) {
- pageno = bitmap_find_next_zero_area(cma->bitmap, cma->count,
- start, count, mask);
- if (pageno >= cma->count)
- break;
-
- pfn = cma->base_pfn + pageno;
- ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA);
- if (ret == 0) {
- bitmap_set(cma->bitmap, pageno, count);
- page = pfn_to_page(pfn);
- break;
- } else if (ret != -EBUSY) {
- break;
- }
- 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 = pageno + mask + 1;
- }
-
- mutex_unlock(&cma_mutex);
- pr_debug("%s(): returned %p\n", __func__, page);
- return page;
+ return cma_alloc(dev_get_cma_area(dev), count, align);
}
/**
bool dma_release_from_contiguous(struct device *dev, struct page *pages,
int count)
{
- struct cma *cma = dev_get_cma_area(dev);
- unsigned long pfn;
+ return cma_release(dev_get_cma_area(dev), pages, count);
+}
- if (!cma || !pages)
- return false;
+/*
+ * Support for reserved memory regions defined in device tree
+ */
+#ifdef CONFIG_OF_RESERVED_MEM
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
- pr_debug("%s(page %p)\n", __func__, (void *)pages);
+#undef pr_fmt
+#define pr_fmt(fmt) fmt
- pfn = page_to_pfn(pages);
+static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev)
+{
+ dev_set_cma_area(dev, rmem->priv);
+ return 0;
+}
- if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count)
- return false;
+static void rmem_cma_device_release(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ dev_set_cma_area(dev, NULL);
+}
+
+static const struct reserved_mem_ops rmem_cma_ops = {
+ .device_init = rmem_cma_device_init,
+ .device_release = rmem_cma_device_release,
+};
- VM_BUG_ON(pfn + count > cma->base_pfn + cma->count);
+static int __init rmem_cma_setup(struct reserved_mem *rmem)
+{
+ phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+ phys_addr_t mask = align - 1;
+ unsigned long node = rmem->fdt_node;
+ struct cma *cma;
+ int err;
- mutex_lock(&cma_mutex);
- bitmap_clear(cma->bitmap, pfn - cma->base_pfn, count);
- free_contig_range(pfn, count);
- mutex_unlock(&cma_mutex);
+ if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
+ of_get_flat_dt_prop(node, "no-map", NULL))
+ return -EINVAL;
- return true;
+ if ((rmem->base & mask) || (rmem->size & mask)) {
+ pr_err("Reserved memory: incorrect alignment of CMA region\n");
+ return -EINVAL;
+ }
+
+ err = cma_init_reserved_mem(rmem->base, rmem->size, 0, &cma);
+ if (err) {
+ pr_err("Reserved memory: unable to setup CMA region\n");
+ return err;
+ }
+ /* Architecture specific contiguous memory fixup. */
+ dma_contiguous_early_fixup(rmem->base, rmem->size);
+
+ if (of_get_flat_dt_prop(node, "linux,cma-default", NULL))
+ dma_contiguous_set_default(cma);
+
+ rmem->ops = &rmem_cma_ops;
+ rmem->priv = cma;
+
+ pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+
+ return 0;
}
+RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);
+#endif