PCI: Remove redundant PCI_VSEC_HDR and PCI_VSEC_HDR_LEN_SHIFT

Remove duplicate macro PCI_VSEC_HDR and its related macro
PCI_VSEC_HDR_LEN_SHIFT from pci_regs.h to avoid redundancy and
inconsistencies. Update VFIO PCI code to use PCI_VNDR_HEADER and
PCI_VNDR_HEADER_LEN() for consistent naming and functionality.

These changes aim to streamline header handling while minimizing impact,
given the niche usage of these macros in userspace.

Link: https://lore.kernel.org/r/20241216013536.4487-1-zhangdongdong@eswincomputing.com
Signed-off-by: Dongdong Zhang <zhangdongdong@eswincomputing.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index ea2745c1ac5e686caba729c80ddf91ce790cff8e..5572fd99b921fb99ca37300340962928f09d7ca9 100644 (file)
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1389,11 +1389,12 @@ static int vfio_ext_cap_len(struct vfio_pci_core_device *vdev, u16 ecap, u16 epo
 
        switch (ecap) {
        case PCI_EXT_CAP_ID_VNDR:
-               ret = pci_read_config_dword(pdev, epos + PCI_VSEC_HDR, &dword);
+               ret = pci_read_config_dword(pdev, epos + PCI_VNDR_HEADER,
+                                           &dword);
                if (ret)
                        return pcibios_err_to_errno(ret);
 
-               return dword >> PCI_VSEC_HDR_LEN_SHIFT;
+               return PCI_VNDR_HEADER_LEN(dword);
        case PCI_EXT_CAP_ID_VC:
        case PCI_EXT_CAP_ID_VC9:
        case PCI_EXT_CAP_ID_MFVC:

diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 02d0ba2999e04a46d2f436ee3ea4dd5cbdbeaf7f..c2ccc85c43edd868e0972e290f77270547c7e117 100644 (file)
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -1001,9 +1001,6 @@
 #define PCI_ACS_CTRL           0x06    /* ACS Control Register */
 #define PCI_ACS_EGRESS_CTL_V   0x08    /* ACS Egress Control Vector */
 
-#define PCI_VSEC_HDR           4       /* extended cap - vendor-specific */
-#define  PCI_VSEC_HDR_LEN_SHIFT        20      /* shift for length field */
-
 /* SATA capability */
 #define PCI_SATA_REGS          4       /* SATA REGs specifier */
 #define  PCI_SATA_REGS_MASK    0xF     /* location - BAR#/inline */