On Fri, Aug 16, 2019 at 12:24:27PM +0300, Denis Efremov wrote:

Code that iterates over all standard PCI BARs typically uses
PCI_STD_RESOURCE_END, but this is error-prone because it requires
"i <= PCI_STD_RESOURCE_END" rather than something like
"i < PCI_STD_NUM_BARS". We could add such a definition and use it the same
way PCI_SRIOV_NUM_BARS is used. There is already the definition
PCI_BAR_COUNT for s390 only. Thus, this patchset introduces it globally.

Changes in v2:
  - Reverse checks in pci_iomap_range,pci_iomap_wc_range.
  - Refactor loops in vfio_pci to keep PCI_STD_RESOURCES.
  - Add 2 new patches to replace the magic constant with new define.
  - Split net patch in v1 to separate stmmac and dwc-xlgmac patches.

Denis Efremov (10):
  PCI: Add define for the number of standard PCI BARs
  s390/pci: Loop using PCI_STD_NUM_BARS
  x86/PCI: Loop using PCI_STD_NUM_BARS
  stmmac: pci: Loop using PCI_STD_NUM_BARS
  net: dwc-xlgmac: Loop using PCI_STD_NUM_BARS
  rapidio/tsi721: Loop using PCI_STD_NUM_BARS
  efifb: Loop using PCI_STD_NUM_BARS
  vfio_pci: Loop using PCI_STD_NUM_BARS
  PCI: hv: Use PCI_STD_NUM_BARS
  PCI: Use PCI_STD_NUM_BARS

 arch/s390/include/asm/pci.h                      |  5 +----
 arch/s390/include/asm/pci_clp.h                  |  6 +++---
 arch/s390/pci/pci.c                              | 16 ++++++++--------
 arch/s390/pci/pci_clp.c                          |  6 +++---
 arch/x86/pci/common.c                            |  2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c |  4 ++--
 drivers/net/ethernet/synopsys/dwc-xlgmac-pci.c   |  2 +-
 drivers/pci/controller/pci-hyperv.c              | 10 +++++-----
 drivers/pci/pci.c                                | 11 ++++++-----
 drivers/pci/quirks.c                             |  4 ++--
 drivers/rapidio/devices/tsi721.c                 |  2 +-
 drivers/vfio/pci/vfio_pci.c                      | 11 +++++++----
 drivers/vfio/pci/vfio_pci_config.c               | 10 ++++++----
 drivers/vfio/pci/vfio_pci_private.h              |  4 ++--
 drivers/video/fbdev/efifb.c                      |  2 +-
 include/linux/pci.h                              |  2 +-
 include/uapi/linux/pci_regs.h                    |  1 +
 17 files changed, 51 insertions(+), 47 deletions(-)

I've come across a few more places where this change can be made. There
may be multiple instances in the same file, but only the first is shown
below:

drivers/misc/pci_endpoint_test.c:       for (bar = BAR_0; bar <= BAR_5; bar++) {
drivers/net/ethernet/intel/e1000/e1000_main.c:          for (i = BAR_1; i <= BAR_5; i++) {
drivers/net/ethernet/intel/ixgb/ixgb_main.c:    for (i = BAR_1; i <= BAR_5; i++) {
drivers/pci/controller/dwc/pci-dra7xx.c:        for (bar = BAR_0; bar <= BAR_5; bar++)
drivers/pci/controller/dwc/pci-layerscape-ep.c: for (bar = BAR_0; bar <= BAR_5; bar++)
drivers/pci/controller/dwc/pcie-artpec6.c:      for (bar = BAR_0; bar <= BAR_5; bar++)
drivers/pci/controller/dwc/pcie-designware-plat.c:      for (bar = BAR_0; bar <= BAR_5; bar++)
drivers/pci/endpoint/functions/pci-epf-test.c:  for (bar = BAR_0; bar <= BAR_5; bar++) {
include/linux/pci-epc.h:        u64     bar_fixed_size[BAR_5 + 1];
drivers/scsi/pm8001/pm8001_hwi.c:       for (bar = 0; bar < 6; bar++) {
drivers/scsi/pm8001/pm8001_init.c:      for (bar = 0; bar < 6; bar++) {
drivers/ata/sata_nv.c:  for (bar = 0; bar < 6; bar++)
drivers/video/fbdev/core/fbmem.c:       for (idx = 0, bar = 0; bar < PCI_ROM_RESOURCE; bar++) {
drivers/staging/gasket/gasket_core.c:   for (i = 0; i < GASKET_NUM_BARS; i++) {
drivers/tty/serial/8250/8250_pci.c:     for (i = 0; i < PCI_NUM_BAR_RESOURCES; i++) { <-----------

It looks like BARs are often iterated with PCI_NUM_BAR_RESOURCES, there
are a load of these too found with:

git grep PCI_ROM_RESOURCE | grep "< "

I'm happy to share patches if preferred.

Thanks,

Andrew Murray

-- 
2.21.0