Merge tag 'dma-mapping-6.7-2023-11-10' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:

 - don't leave pages decrypted for DMA in encrypted memory setups linger
   around on failure (Petr Tesarik)

 - fix an out of bounds access in the new dynamic swiotlb code (Petr
   Tesarik)

 - fix dma_addressing_limited for systems with weird physical memory
   layouts (Jia He)

* tag 'dma-mapping-6.7-2023-11-10' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: fix out-of-bounds TLB allocations with CONFIG_SWIOTLB_DYNAMIC
  dma-mapping: fix dma_addressing_limited() if dma_range_map can't cover all system RAM
  dma-mapping: move dma_addressing_limited() out of line
  swiotlb: do not free decrypted pages if dynamic

1 files changed, 40 insertions, 0 deletions

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index ed3056eb20b8..73c95815789a 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -587,6 +587,46 @@ int dma_direct_supported(struct device *dev, u64 mask)
 	return mask >= phys_to_dma_unencrypted(dev, min_mask);
 }
 
+/*
+ * To check whether all ram resource ranges are covered by dma range map
+ * Returns 0 when further check is needed
+ * Returns 1 if there is some RAM range can't be covered by dma_range_map
+ */
+static int check_ram_in_range_map(unsigned long start_pfn,
+				  unsigned long nr_pages, void *data)
+{
+	unsigned long end_pfn = start_pfn + nr_pages;
+	const struct bus_dma_region *bdr = NULL;
+	const struct bus_dma_region *m;
+	struct device *dev = data;
+
+	while (start_pfn < end_pfn) {
+		for (m = dev->dma_range_map; PFN_DOWN(m->size); m++) {
+			unsigned long cpu_start_pfn = PFN_DOWN(m->cpu_start);
+
+			if (start_pfn >= cpu_start_pfn &&
+			    start_pfn - cpu_start_pfn < PFN_DOWN(m->size)) {
+				bdr = m;
+				break;
+			}
+		}
+		if (!bdr)
+			return 1;
+
+		start_pfn = PFN_DOWN(bdr->cpu_start) + PFN_DOWN(bdr->size);
+	}
+
+	return 0;
+}
+
+bool dma_direct_all_ram_mapped(struct device *dev)
+{
+	if (!dev->dma_range_map)
+		return true;
+	return !walk_system_ram_range(0, PFN_DOWN(ULONG_MAX) + 1, dev,
+				      check_ram_in_range_map);
+}
+
 size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */