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authorJakub Kicinski <kuba@kernel.org>2023-10-05 13:16:31 -0700
committerJakub Kicinski <kuba@kernel.org>2023-10-05 13:16:47 -0700
commit2606cf059c56bfb86d5d6bd0f41bd7eedefc8b0a (patch)
tree6bd918ad4fc55e677cc6ccb3212eab873c467c7f /include/linux/swiotlb.h
parent49e7265fd098fdade2bbdd9331e6b914cda7fa83 (diff)
parentf291209eca5eba0b4704fa0832af57b12dbc1a02 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts (or adjacent changes of note). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux/swiotlb.h')
-rw-r--r--include/linux/swiotlb.h23
1 files changed, 16 insertions, 7 deletions
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index b4536626f8ff..ecde0312dd52 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -172,14 +172,23 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
if (!mem)
return false;
- if (IS_ENABLED(CONFIG_SWIOTLB_DYNAMIC)) {
- /* Pairs with smp_wmb() in swiotlb_find_slots() and
- * swiotlb_dyn_alloc(), which modify the RCU lists.
- */
- smp_rmb();
- return swiotlb_find_pool(dev, paddr);
- }
+#ifdef CONFIG_SWIOTLB_DYNAMIC
+ /*
+ * All SWIOTLB buffer addresses must have been returned by
+ * swiotlb_tbl_map_single() and passed to a device driver.
+ * If a SWIOTLB address is checked on another CPU, then it was
+ * presumably loaded by the device driver from an unspecified private
+ * data structure. Make sure that this load is ordered before reading
+ * dev->dma_uses_io_tlb here and mem->pools in swiotlb_find_pool().
+ *
+ * This barrier pairs with smp_mb() in swiotlb_find_slots().
+ */
+ smp_rmb();
+ return READ_ONCE(dev->dma_uses_io_tlb) &&
+ swiotlb_find_pool(dev, paddr);
+#else
return paddr >= mem->defpool.start && paddr < mem->defpool.end;
+#endif
}
static inline bool is_swiotlb_force_bounce(struct device *dev)