swiotlb: Make io_tlb_end a physical address instead of a virtual one
This change replaces all references to the virtual address for io_tlb_end
with references to the physical address io_tlb_end. The main advantage of
replacing the virtual address with a physical address is that we can avoid
having to do multiple translations from the virtual address to the physical
one needed for testing an existing DMA address.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index f114bf6..c0cbfa1 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -57,7 +57,8 @@
* swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
* API.
*/
-static char *io_tlb_start, *io_tlb_end;
+static char *io_tlb_start;
+static phys_addr_t io_tlb_end;
/*
* The number of IO TLB blocks (in groups of 64) between io_tlb_start and
@@ -125,14 +126,16 @@
void swiotlb_print_info(void)
{
unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
- phys_addr_t pstart, pend;
+ phys_addr_t pstart;
+ unsigned char *vend;
pstart = virt_to_phys(io_tlb_start);
- pend = virt_to_phys(io_tlb_end);
+ vend = phys_to_virt(io_tlb_end);
printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n",
- (unsigned long long)pstart, (unsigned long long)pend - 1,
- bytes >> 20, io_tlb_start, io_tlb_end - 1);
+ (unsigned long long)pstart,
+ (unsigned long long)io_tlb_end,
+ bytes >> 20, io_tlb_start, vend - 1);
}
void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
@@ -143,7 +146,7 @@
io_tlb_nslabs = nslabs;
io_tlb_start = tlb;
- io_tlb_end = io_tlb_start + bytes;
+ io_tlb_end = __pa(io_tlb_start) + bytes;
/*
* Allocate and initialize the free list array. This array is used
@@ -254,7 +257,7 @@
io_tlb_nslabs = nslabs;
io_tlb_start = tlb;
- io_tlb_end = io_tlb_start + bytes;
+ io_tlb_end = virt_to_phys(io_tlb_start) + bytes;
memset(io_tlb_start, 0, bytes);
@@ -304,7 +307,7 @@
sizeof(int)));
io_tlb_list = NULL;
cleanup2:
- io_tlb_end = NULL;
+ io_tlb_end = 0;
io_tlb_start = NULL;
io_tlb_nslabs = 0;
return -ENOMEM;
@@ -339,8 +342,7 @@
static int is_swiotlb_buffer(phys_addr_t paddr)
{
- return paddr >= virt_to_phys(io_tlb_start) &&
- paddr < virt_to_phys(io_tlb_end);
+ return paddr >= virt_to_phys(io_tlb_start) && paddr < io_tlb_end;
}
/*
@@ -938,6 +940,6 @@
int
swiotlb_dma_supported(struct device *hwdev, u64 mask)
{
- return swiotlb_virt_to_bus(hwdev, io_tlb_end - 1) <= mask;
+ return phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
}
EXPORT_SYMBOL(swiotlb_dma_supported);