Merge branch 'stable/for-linus-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb

Pull swiotlb updates from Konrad Rzeszutek Wilk:
 "Cleanups in the swiotlb code and extra debugfs knobs to help with the
  field diagnostics"

* 'stable/for-linus-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb-xen: ensure we have a single callsite for xen_dma_map_page
  swiotlb-xen: simplify the DMA sync method implementations
  swiotlb-xen: use ->map_page to implement ->map_sg
  swiotlb-xen: make instances match their method names
  swiotlb: save io_tlb_used to local variable before leaving critical section
  swiotlb: dump used and total slots when swiotlb buffer is full

1 files changed, 5 insertions, 1 deletions

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 53012db1e53c..6f7619c1f877 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -452,6 +452,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
         unsigned long mask;
         unsigned long offset_slots;
         unsigned long max_slots;
+        unsigned long tmp_io_tlb_used;
 
         if (no_iotlb_memory)
                 panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");
@@ -538,9 +539,12 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
         } while (index != wrap);
 
 not_found:
+        tmp_io_tlb_used = io_tlb_used;
+
         spin_unlock_irqrestore(&io_tlb_lock, flags);
         if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit())
-                dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
+                dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n",
+                         size, io_tlb_nslabs, tmp_io_tlb_used);
         return DMA_MAPPING_ERROR;
 found:
         io_tlb_used += nslots;