PCI/P2PDMA: Remove redundant bus_offset from map state

Remove the bus_off field from pci_p2pdma_map_state since it duplicates
information already available in the pgmap structure. The bus_offset
is only used in one location (pci_p2pdma_bus_addr_map) and is always
identical to pgmap->bus_offset.

Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>

Author: rleon

drivers/pci/p2pdma.c

@@ -1009,7 +1009,6 @@ void __pci_p2pdma_update_state(struct pci_p2pdma_map_state *state,
 {
 	state->pgmap = page_pgmap(page);
 	state->map = pci_p2pdma_map_type(state->pgmap, dev);
-	state->bus_off = to_p2p_pgmap(state->pgmap)->bus_offset;
 }
 
 /**

include/linux/pci-p2pdma.h

@@ -146,7 +146,6 @@ enum pci_p2pdma_map_type {
 struct pci_p2pdma_map_state {
 	struct dev_pagemap *pgmap;
 	enum pci_p2pdma_map_type map;
-	u64 bus_off;
 };
 
 /* helper for pci_p2pdma_state(), do not use directly */
@@ -186,7 +185,7 @@ static inline dma_addr_t
 pci_p2pdma_bus_addr_map(struct pci_p2pdma_map_state *state, phys_addr_t paddr)
 {
 	WARN_ON_ONCE(state->map != PCI_P2PDMA_MAP_BUS_ADDR);
-	return paddr + state->bus_off;
+	return paddr + to_p2p_pgmap(state->pgmap)->bus_offsetf;
 }
 
 #endif /* _LINUX_PCI_P2P_H */