[PATCH 5.11 15/31] swiotlb: factor out an io_tlb_offset helper

Greg Kroah-Hartman
2021-05-05T12:11:30Z

From: Jianxiong Gao <jxgao@google.com>

commit: c7fbeca757fe74135d8b6a4c8ddaef76f5775d68

Replace the very genericly named OFFSET macro with a little inline
helper that hardcodes the alignment to the only value ever passed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jianxiong Gao <jxgao@google.com>
Tested-by: Jianxiong Gao <jxgao@google.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jianxiong Gao <jxgao@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/dma/swiotlb.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)

--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -50,9 +50,6 @@
#define CREATE_TRACE_POINTS
#include <trace/events/swiotlb.h>

-#define OFFSET(val,align) ((unsigned long) \
- ( (val) & ( (align) - 1)))
-
#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))

/*
@@ -192,6 +189,11 @@ void swiotlb_print_info(void)
bytes >> 20);
}

+static inline unsigned long io_tlb_offset(unsigned long val)
+{
+ return val & (IO_TLB_SEGSIZE - 1);
+}
+
/*
* Early SWIOTLB allocation may be too early to allow an architecture to
* perform the desired operations. This function allows the architecture to
@@ -241,7 +243,7 @@ int __init swiotlb_init_with_tbl(char *t
__func__, alloc_size, PAGE_SIZE);

for (i = 0; i < io_tlb_nslabs; i++) {
- io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);
io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
}
io_tlb_index = 0;
@@ -375,7 +377,7 @@ swiotlb_late_init_with_tbl(char *tlb, un
goto cleanup4;

for (i = 0; i < io_tlb_nslabs; i++) {
- io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);
io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
}
io_tlb_index = 0;
@@ -546,7 +548,9 @@ phys_addr_t swiotlb_tbl_map_single(struc

for (i = index; i < (int) (index + nslots); i++)
io_tlb_list[i] = 0;
- for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
+ for (i = index - 1;
+ io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
+ io_tlb_list[i]; i--)
io_tlb_list[i] = ++count;
tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT);

@@ -632,7 +636,9 @@ void swiotlb_tbl_unmap_single(struct dev
* Step 2: merge the returned slots with the preceding slots,
* if available (non zero)
*/
- for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
+ for (i = index - 1;
+ io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
+ io_tlb_list[i]; i--)
io_tlb_list[i] = ++count;

io_tlb_used -= nslots;