[PATCH v3 1/6] base: dma-contiguous: add dma_contiguous_init_reserved_mem() function
Marek Szyprowski
m.szyprowski at samsung.com
Tue Feb 18 08:37:56 EST 2014
Add new dma_contiguous_init_reserved_mem() function, which creates CMA area
from previously reserved memory region.
Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
drivers/base/dma-contiguous.c | 70 +++++++++++++++++++++++++++-------------
include/linux/dma-contiguous.h | 7 ++++
2 files changed, 55 insertions(+), 22 deletions(-)
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 165c2c299e57..ece82e8f3a8b 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -182,6 +182,53 @@ static int __init cma_init_reserved_areas(void)
core_initcall(cma_init_reserved_areas);
/**
+ * dma_contiguous_init_reserved_mem() - 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.
+ *
+ * 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.
+ */
+int __init dma_contiguous_init_reserved_mem(phys_addr_t size, phys_addr_t base,
+ struct cma **res_cma)
+{
+ struct cma *cma = &cma_areas[cma_area_count];
+ phys_addr_t alignment;
+
+ /* 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;
+
+ /* Sanitise input arguments */
+ alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+ if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != size)
+ return -EINVAL;
+
+ cma->base_pfn = PFN_DOWN(base);
+ cma->count = size >> PAGE_SHIFT;
+ *res_cma = cma;
+ cma_area_count++;
+
+ pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
+ (unsigned long)base);
+
+ /* Architecture specific contiguous memory fixup. */
+ dma_contiguous_early_fixup(base, size);
+ return 0;
+}
+
+
+/**
* 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
@@ -197,7 +244,6 @@ core_initcall(cma_init_reserved_areas);
int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
phys_addr_t limit, struct cma **res_cma)
{
- struct cma *cma = &cma_areas[cma_area_count];
phys_addr_t alignment;
int ret = 0;
@@ -205,12 +251,6 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
(unsigned long)size, (unsigned long)base,
(unsigned long)limit);
- /* Sanity checks */
- if (cma_area_count == ARRAY_SIZE(cma_areas)) {
- pr_err("Not enough slots for CMA reserved regions!\n");
- return -ENOSPC;
- }
-
if (!size)
return -EINVAL;
@@ -241,21 +281,7 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
}
}
- /*
- * 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;
- *res_cma = cma;
- cma_area_count++;
-
- pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
- (unsigned long)base);
-
- /* Architecture specific contiguous memory fixup. */
- dma_contiguous_early_fixup(base, size);
- return 0;
+ return dma_contiguous_init_reserved_mem(size, base, res_cma);
err:
pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
return ret;
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index 3b28f937d959..550497393ae7 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -90,6 +90,8 @@ void dma_contiguous_reserve(phys_addr_t addr_limit);
int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
phys_addr_t limit, struct cma **res_cma);
+int dma_contiguous_init_reserved_mem(phys_addr_t size, phys_addr_t base,
+ struct cma **res_cma);
/**
* dma_declare_contiguous() - reserve area for contiguous memory handling
* for particular device
@@ -140,6 +142,11 @@ static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base
return -ENOSYS;
}
+static inline int dma_contiguous_init_reserved_mem(phys_addr_t size,
+ phys_addr_t base, struct cma **res_cma) {
+ return -ENOSYS;
+}
+
static inline
int dma_declare_contiguous(struct device *dev, phys_addr_t size,
phys_addr_t base, phys_addr_t limit)
--
1.7.9.5
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