[PATCH v1 01/10] PCI/P2PDMA: Remove redundant bus_offset from map state

Leon Romanovsky
2025-08-04T13:01:01Z

From: Leon Romanovsky <leonro@nvidia.com>

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.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
drivers/pci/p2pdma.c | 1 -
include/linux/pci-p2pdma.h | 3 +--
2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index da5657a020074..274bb7bcc0bc5 100644
--- a/drivers/pci/p2pdma.c
+++ b/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;
}

/**
diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h
index 075c20b161d98..b502fc8b49bf9 100644
--- a/include/linux/pci-p2pdma.h
+++ b/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 */
--
2.50.1