Revert "Revert "swiotlb: factor out a nr_slots helper""

This reverts commit cb27079661.

Bring back the commit in 5.10.35 that broke the kabi.

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I14e92ad7064f5d3f4334d17bdb78444dff45cab3
This commit is contained in:
Greg Kroah-Hartman 2021-05-10 14:20:51 +02:00 committed by Todd Kjos
parent 7b5e000065
commit 2893baee79

View File

@ -178,6 +178,11 @@ static inline unsigned long io_tlb_offset(unsigned long val)
return val & (IO_TLB_SEGSIZE - 1);
}
static inline unsigned long nr_slots(u64 val)
{
return DIV_ROUND_UP(val, IO_TLB_SIZE);
}
/*
* Early SWIOTLB allocation may be too early to allow an architecture to
* perform the desired operations. This function allows the architecture to
@ -477,20 +482,20 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
tbl_dma_addr &= mask;
offset_slots = ALIGN(tbl_dma_addr, IO_TLB_SIZE) >> IO_TLB_SHIFT;
offset_slots = nr_slots(tbl_dma_addr);
/*
* Carefully handle integer overflow which can occur when mask == ~0UL.
*/
max_slots = mask + 1
? ALIGN(mask + 1, IO_TLB_SIZE) >> IO_TLB_SHIFT
? nr_slots(mask + 1)
: 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
/*
* For mappings greater than or equal to a page, we limit the stride
* (and hence alignment) to a page size.
*/
nslots = ALIGN(alloc_size, IO_TLB_SIZE) >> IO_TLB_SHIFT;
nslots = nr_slots(alloc_size);
if (alloc_size >= PAGE_SIZE)
stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
else
@ -586,7 +591,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
enum dma_data_direction dir, unsigned long attrs)
{
unsigned long flags;
int i, count, nslots = ALIGN(alloc_size, IO_TLB_SIZE) >> IO_TLB_SHIFT;
int i, count, nslots = nr_slots(alloc_size);
int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
phys_addr_t orig_addr = io_tlb_orig_addr[index];