swiotlb: add the swiotlb initialization function with iotlb memory

This enables the caller to initialize swiotlb with its own iotlb
memory.

See "swiotlb: swiotlb: add swiotlb_tbl_map_single library function" for
full description of patchset.

[v2: changed ..with_tlb to ..with_tbl]

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Albert Herranz <albert_herranz@yahoo.es>

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 81a4e213c6cf9bd934792d0135836cc9ef8d4d36..b406261d88871206742d827d38772941ebfa6a32 100644 (file)
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -23,6 +23,7 @@ extern int swiotlb_force;
 #define IO_TLB_SHIFT 11
 
 extern void swiotlb_init(int verbose);
+extern void swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
 
 extern void
 *swiotlb_alloc_coherent(struct device *hwdev, size_t size,

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 783aff00024c8a3ef8d9368718556d49ef0c5e1b..ec61e1507d0ac4f26ed77786546ff481a795cb55 100644 (file)
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -140,28 +140,14 @@ void swiotlb_print_info(void)
               (unsigned long long)pend);
 }
 
-/*
- * Statically reserve bounce buffer space and initialize bounce buffer data
- * structures for the software IO TLB used to implement the DMA API.
- */
-void __init
-swiotlb_init_with_default_size(size_t default_size, int verbose)
+void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
 {
        unsigned long i, bytes;
 
-       if (!io_tlb_nslabs) {
-               io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
-               io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
-       }
+       bytes = nslabs << IO_TLB_SHIFT;
 
-       bytes = io_tlb_nslabs << IO_TLB_SHIFT;
-
-       /*
-        * Get IO TLB memory from the low pages
-        */
-       io_tlb_start = alloc_bootmem_low_pages(bytes);
-       if (!io_tlb_start)
-               panic("Cannot allocate SWIOTLB buffer");
+       io_tlb_nslabs = nslabs;
+       io_tlb_start = tlb;
        io_tlb_end = io_tlb_start + bytes;
 
        /*
@@ -185,6 +171,32 @@ swiotlb_init_with_default_size(size_t default_size, int verbose)
                swiotlb_print_info();
 }
 
+/*
+ * Statically reserve bounce buffer space and initialize bounce buffer data
+ * structures for the software IO TLB used to implement the DMA API.
+ */
+void __init
+swiotlb_init_with_default_size(size_t default_size, int verbose)
+{
+       unsigned long bytes;
+
+       if (!io_tlb_nslabs) {
+               io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
+               io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+       }
+
+       bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+
+       /*
+        * Get IO TLB memory from the low pages
+        */
+       io_tlb_start = alloc_bootmem_low_pages(bytes);
+       if (!io_tlb_start)
+               panic("Cannot allocate SWIOTLB buffer");
+
+       swiotlb_init_with_tbl(io_tlb_start, io_tlb_nslabs, verbose);
+}
+
 void __init
 swiotlb_init(int verbose)
 {