[PATCH v3 14/14] PCI/P2PDMA: Update pci_p2pdma_distance_many() documentation

From: Logan Gunthorpe
Date: Mon Aug 12 2019 - 13:31:29 EST


The comment describing pci_p2pdma_distance_many() still referred to
the devices being behind the same root port. This no longer applies
so reword the documentation.

Link: https://lore.kernel.org/r/20190730163545.4915-15-logang@xxxxxxxxxxxx
Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
drivers/pci/p2pdma.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index d8c824097d26..0608aae72ccc 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -517,15 +517,14 @@ upstream_bridge_distance_warn(struct pci_dev *provider, struct pci_dev *client,
* @num_clients: number of clients in the array
* @verbose: if true, print warnings for devices when we return -1
*
- * Returns -1 if any of the clients are not compatible (behind the same
- * root port as the provider), otherwise returns a positive number where
- * a lower number is the preferable choice. (If there's one client
- * that's the same as the provider it will return 0, which is best choice).
+ * Returns -1 if any of the clients are not compatible, otherwise returns a
+ * positive number where a lower number is the preferable choice. (If there's
+ * one client that's the same as the provider it will return 0, which is best
+ * choice).
*
- * For now, "compatible" means the provider and the clients are all behind
- * the same PCI root port. This cuts out cases that may work but is safest
- * for the user. Future work can expand this to white-list root complexes that
- * can safely forward between each ports.
+ * "compatible" means the provider and the clients are either all behind
+ * the same PCI root port or the host bridges connected to each of the devices
+ * are listed in the 'pci_p2pdma_whitelist'.
*/
int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
int num_clients, bool verbose)
--
2.20.1