swiotlb: remove unused swiotlb_alloc_boot()

Nobody uses swiotlb_alloc_boot().
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>

arch/x86/kernel/pci-swiotlb.c

@@ -13,11 +13,6 @@
 
 int swiotlb __read_mostly;
 
-void * __init swiotlb_alloc_boot(size_t size, unsigned long nslabs)
-{
-	return alloc_bootmem_low_pages(size);
-}
-
 void *swiotlb_alloc(unsigned order, unsigned long nslabs)
 {
 	return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order);

include/linux/swiotlb.h

@@ -14,7 +14,6 @@ struct scatterlist;
  */
 #define IO_TLB_SEGSIZE	128
 
-
 /*
  * log of the size of each IO TLB slab.  The number of slabs is command line
  * controllable.
@@ -24,7 +23,6 @@ struct scatterlist;
 extern void
 swiotlb_init(void);
 
-extern void *swiotlb_alloc_boot(size_t bytes, unsigned long nslabs);
 extern void *swiotlb_alloc(unsigned order, unsigned long nslabs);
 
 extern dma_addr_t swiotlb_phys_to_bus(struct device *hwdev,

lib/swiotlb.c

@@ -114,11 +114,6 @@ setup_io_tlb_npages(char *str)
 __setup("swiotlb=", setup_io_tlb_npages);
 /* make io_tlb_overflow tunable too? */
 
-void * __weak __init swiotlb_alloc_boot(size_t size, unsigned long nslabs)
-{
-	return alloc_bootmem_low_pages(size);
-}
-
 void * __weak swiotlb_alloc(unsigned order, unsigned long nslabs)
 {
 	return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order);
@@ -189,7 +184,7 @@ swiotlb_init_with_default_size(size_t default_size)
 	/*
 	 * Get IO TLB memory from the low pages
 	 */
-	io_tlb_start = swiotlb_alloc_boot(bytes, io_tlb_nslabs);
+	io_tlb_start = alloc_bootmem_low_pages(bytes);
 	if (!io_tlb_start)
 		panic("Cannot allocate SWIOTLB buffer");
 	io_tlb_end = io_tlb_start + bytes;