diff options
| -rw-r--r-- | lib/swiotlb.c | 89 |
1 files changed, 43 insertions, 46 deletions
diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 025922807e6e..256c8445e54d 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -331,56 +331,53 @@ map_single(struct device *hwdev, char *buffer, size_t size, int dir) * request and allocate a buffer from that IO TLB pool. */ spin_lock_irqsave(&io_tlb_lock, flags); - { - index = ALIGN(io_tlb_index, stride); - if (index >= io_tlb_nslabs) - index = 0; - wrap = index; - - do { - while (is_span_boundary(index, nslots, offset_slots, - max_slots)) { - index += stride; - if (index >= io_tlb_nslabs) - index = 0; - if (index == wrap) - goto not_found; - } - - /* - * If we find a slot that indicates we have 'nslots' - * number of contiguous buffers, we allocate the - * buffers from that slot and mark the entries as '0' - * indicating unavailable. - */ - if (io_tlb_list[index] >= nslots) { - int count = 0; - - 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--) - io_tlb_list[i] = ++count; - dma_addr = io_tlb_start + (index << IO_TLB_SHIFT); - - /* - * Update the indices to avoid searching in - * the next round. - */ - io_tlb_index = ((index + nslots) < io_tlb_nslabs - ? (index + nslots) : 0); - - goto found; - } + index = ALIGN(io_tlb_index, stride); + if (index >= io_tlb_nslabs) + index = 0; + wrap = index; + + do { + while (is_span_boundary(index, nslots, offset_slots, + max_slots)) { index += stride; if (index >= io_tlb_nslabs) index = 0; - } while (index != wrap); + if (index == wrap) + goto not_found; + } - not_found: - spin_unlock_irqrestore(&io_tlb_lock, flags); - return NULL; - } - found: + /* + * If we find a slot that indicates we have 'nslots' number of + * contiguous buffers, we allocate the buffers from that slot + * and mark the entries as '0' indicating unavailable. + */ + if (io_tlb_list[index] >= nslots) { + int count = 0; + + 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--) + io_tlb_list[i] = ++count; + dma_addr = io_tlb_start + (index << IO_TLB_SHIFT); + + /* + * Update the indices to avoid searching in the next + * round. + */ + io_tlb_index = ((index + nslots) < io_tlb_nslabs + ? (index + nslots) : 0); + + goto found; + } + index += stride; + if (index >= io_tlb_nslabs) + index = 0; + } while (index != wrap); + +not_found: + spin_unlock_irqrestore(&io_tlb_lock, flags); + return NULL; +found: spin_unlock_irqrestore(&io_tlb_lock, flags); /* |