[PATCH 08/10] swiotlb: add swiotlb_free function

FUJITA Tomonori
2009-10-28T06:54:29Z

swiotlb_free function frees all allocated memory for swiotlb.

We need to initialize swiotlb before IOMMU initialization (x86 and
powerpc needs to allocate memory from bootmem allocator). If IOMMU
initialization is successful, we need to free swiotlb resource (don't
want to waste 64MB).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---
include/linux/swiotlb.h | 1 +
lib/swiotlb.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 73b1f1c..51b6cc2 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -88,4 +88,5 @@ swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr);
extern int
swiotlb_dma_supported(struct device *hwdev, u64 mask);

+extern void __init swiotlb_free(void);
#endif /* __LINUX_SWIOTLB_H */
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index ac25cd2..eee512b 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -97,6 +97,8 @@ static phys_addr_t *io_tlb_orig_addr;
*/
static DEFINE_SPINLOCK(io_tlb_lock);

+static int late_alloc;
+
static int __init
setup_io_tlb_npages(char *str)
{
@@ -262,6 +264,8 @@ swiotlb_late_init_with_default_size(size_t default_size)

swiotlb_print_info(bytes);

+ late_alloc = 1;
+
return 0;

cleanup4:
@@ -281,6 +285,32 @@ cleanup1:
return -ENOMEM;
}

+void __init swiotlb_free(void)
+{
+ if (!io_tlb_overflow_buffer)
+ return;
+
+ if (late_alloc) {
+ free_pages((unsigned long)io_tlb_overflow_buffer,
+ get_order(io_tlb_overflow));
+ free_pages((unsigned long)io_tlb_orig_addr,
+ get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
+ free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
+ sizeof(int)));
+ free_pages((unsigned long)io_tlb_start,
+ get_order(io_tlb_nslabs << IO_TLB_SHIFT));
+ } else {
+ free_bootmem_late(__pa(io_tlb_overflow_buffer),
+ io_tlb_overflow);
+ free_bootmem_late(__pa(io_tlb_orig_addr),
+ io_tlb_nslabs * sizeof(phys_addr_t));
+ free_bootmem_late(__pa(io_tlb_list),
+ io_tlb_nslabs * sizeof(int));
+ free_bootmem_late(__pa(io_tlb_start),
+ io_tlb_nslabs << IO_TLB_SHIFT);
+ }
+}
+
static int is_swiotlb_buffer(phys_addr_t paddr)
{
return paddr >= virt_to_phys(io_tlb_start) &&
--
1.5.6.5