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authorTianyu Lan <tiala@microsoft.com>2022-07-21 23:38:46 -0400
committerChristoph Hellwig <hch@lst.de>2022-07-22 17:20:56 +0200
commit72311809031217714e635b24f8478e6ecb0d93d9 (patch)
tree16ba453bcd936f8d97d6f66c3469fb99a3a1581b /kernel/dma
parenta45e52bf1eca9bf8a7d075ce12b1e306497ce393 (diff)
downloadlwn-72311809031217714e635b24f8478e6ecb0d93d9.tar.gz
lwn-72311809031217714e635b24f8478e6ecb0d93d9.zip
swiotlb: clean up some coding style and minor issues
- Fix the used field of struct io_tlb_area wasn't initialized - Set area number to be 0 if input area number parameter is 0 - Use array_size() to calculate io_tlb_area array size - Make parameters of swiotlb_do_find_slots() more reasonable Fixes: 26ffb91fa5e0 ("swiotlb: split up the global swiotlb lock") Signed-off-by: Tianyu Lan <tiala@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/swiotlb.c26
1 files changed, 15 insertions, 11 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 39dee4004439..cc50f1fb127f 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -119,7 +119,10 @@ static bool round_up_default_nslabs(void)
static void swiotlb_adjust_nareas(unsigned int nareas)
{
- if (!is_power_of_2(nareas))
+ /* use a single area when non is specified */
+ if (!nareas)
+ nareas = 1;
+ else if (!is_power_of_2(nareas))
nareas = roundup_pow_of_two(nareas);
default_nareas = nareas;
@@ -276,6 +279,7 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
for (i = 0; i < mem->nareas; i++) {
spin_lock_init(&mem->areas[i].lock);
mem->areas[i].index = 0;
+ mem->areas[i].used = 0;
}
for (i = 0; i < mem->nslabs; i++) {
@@ -358,8 +362,8 @@ retry:
panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
__func__, alloc_size, PAGE_SIZE);
- mem->areas = memblock_alloc(sizeof(struct io_tlb_area) *
- default_nareas, SMP_CACHE_BYTES);
+ mem->areas = memblock_alloc(array_size(sizeof(struct io_tlb_area),
+ default_nareas), SMP_CACHE_BYTES);
if (!mem->areas)
panic("%s: Failed to allocate mem->areas.\n", __func__);
@@ -484,7 +488,7 @@ void __init swiotlb_exit(void)
free_pages((unsigned long)mem->slots, get_order(slots_size));
} else {
memblock_free_late(__pa(mem->areas),
- mem->nareas * sizeof(struct io_tlb_area));
+ array_size(sizeof(*mem->areas), mem->nareas));
memblock_free_late(mem->start, tbl_size);
memblock_free_late(__pa(mem->slots), slots_size);
}
@@ -598,11 +602,12 @@ static unsigned int wrap_area_index(struct io_tlb_mem *mem, unsigned int index)
* Find a suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
*/
-static int swiotlb_do_find_slots(struct io_tlb_mem *mem,
- struct io_tlb_area *area, int area_index,
- struct device *dev, phys_addr_t orig_addr,
- size_t alloc_size, unsigned int alloc_align_mask)
+static int swiotlb_do_find_slots(struct device *dev, int area_index,
+ phys_addr_t orig_addr, size_t alloc_size,
+ unsigned int alloc_align_mask)
{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+ struct io_tlb_area *area = mem->areas + area_index;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
dma_addr_t tbl_dma_addr =
phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;
@@ -691,12 +696,11 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
size_t alloc_size, unsigned int alloc_align_mask)
{
struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
- int start = raw_smp_processor_id() & ((1U << __fls(mem->nareas)) - 1);
+ int start = raw_smp_processor_id() & (mem->nareas - 1);
int i = start, index;
do {
- index = swiotlb_do_find_slots(mem, mem->areas + i, i,
- dev, orig_addr, alloc_size,
+ index = swiotlb_do_find_slots(dev, i, orig_addr, alloc_size,
alloc_align_mask);
if (index >= 0)
return index;