Refactor loops to use idiomatic C style and avoid the fencepost error
of using "i < PCI_STD_RESOURCE_END" when "i <= PCI_STD_RESOURCE_END"
is required, e.g., commit 2f686f1d9bee ("PCI: Correct PCI_STD_RESOURCE_END
usage").

To iterate through all possible BARs, loop conditions changed to the
*number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
valid BAR "i <= PCI_STD_RESOURCE_END".

Cc: Cornelia Huck <coh...@redhat.com>
Cc: Alex Williamson <alex.william...@redhat.com>
Signed-off-by: Denis Efremov <efre...@linux.com>
---
 drivers/vfio/pci/vfio_pci.c         | 11 ++++++----
 drivers/vfio/pci/vfio_pci_config.c  | 32 +++++++++++++++--------------
 drivers/vfio/pci/vfio_pci_private.h |  4 ++--
 3 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 703948c9fbe1..cb7d220d3246 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -110,13 +110,15 @@ static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
 static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
 {
        struct resource *res;
-       int bar;
+       int i;
        struct vfio_pci_dummy_resource *dummy_res;
 
        INIT_LIST_HEAD(&vdev->dummy_resources_list);
 
-       for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
-               res = vdev->pdev->resource + bar;
+       for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+               int bar = i + PCI_STD_RESOURCES;
+
+               res = &vdev->pdev->resource[bar];
 
                if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
                        goto no_mmap;
@@ -399,7 +401,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
 
        vfio_config_free(vdev);
 
-       for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
+       for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+               bar = i + PCI_STD_RESOURCES;
                if (!vdev->barmap[bar])
                        continue;
                pci_iounmap(pdev, vdev->barmap[bar]);
diff --git a/drivers/vfio/pci/vfio_pci_config.c 
b/drivers/vfio/pci/vfio_pci_config.c
index f0891bd8444c..90c0b80f8acf 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -450,30 +450,32 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
 {
        struct pci_dev *pdev = vdev->pdev;
        int i;
-       __le32 *bar;
+       __le32 *vbar;
        u64 mask;
 
-       bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
+       vbar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
 
-       for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) {
-               if (!pci_resource_start(pdev, i)) {
-                       *bar = 0; /* Unmapped by host = unimplemented to user */
+       for (i = 0; i < PCI_STD_NUM_BARS; i++, vbar++) {
+               int bar = i + PCI_STD_RESOURCES;
+
+               if (!pci_resource_start(pdev, bar)) {
+                       *vbar = 0; /* Unmapped by host = unimplemented to user 
*/
                        continue;
                }
 
-               mask = ~(pci_resource_len(pdev, i) - 1);
+               mask = ~(pci_resource_len(pdev, bar) - 1);
 
-               *bar &= cpu_to_le32((u32)mask);
-               *bar |= vfio_generate_bar_flags(pdev, i);
+               *vbar &= cpu_to_le32((u32)mask);
+               *vbar |= vfio_generate_bar_flags(pdev, bar);
 
-               if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
-                       bar++;
-                       *bar &= cpu_to_le32((u32)(mask >> 32));
+               if (*vbar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
+                       vbar++;
+                       *vbar &= cpu_to_le32((u32)(mask >> 32));
                        i++;
                }
        }
 
-       bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
+       vbar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
 
        /*
         * NB. REGION_INFO will have reported zero size if we weren't able
@@ -483,14 +485,14 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
        if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) {
                mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1);
                mask |= PCI_ROM_ADDRESS_ENABLE;
-               *bar &= cpu_to_le32((u32)mask);
+               *vbar &= cpu_to_le32((u32)mask);
        } else if (pdev->resource[PCI_ROM_RESOURCE].flags &
                                        IORESOURCE_ROM_SHADOW) {
                mask = ~(0x20000 - 1);
                mask |= PCI_ROM_ADDRESS_ENABLE;
-               *bar &= cpu_to_le32((u32)mask);
+               *vbar &= cpu_to_le32((u32)mask);
        } else
-               *bar = 0;
+               *vbar = 0;
 
        vdev->bardirty = false;
 }
diff --git a/drivers/vfio/pci/vfio_pci_private.h 
b/drivers/vfio/pci/vfio_pci_private.h
index ee6ee91718a4..8a2c7607d513 100644
--- a/drivers/vfio/pci/vfio_pci_private.h
+++ b/drivers/vfio/pci/vfio_pci_private.h
@@ -86,8 +86,8 @@ struct vfio_pci_reflck {
 
 struct vfio_pci_device {
        struct pci_dev          *pdev;
-       void __iomem            *barmap[PCI_STD_RESOURCE_END + 1];
-       bool                    bar_mmap_supported[PCI_STD_RESOURCE_END + 1];
+       void __iomem            *barmap[PCI_STD_NUM_BARS];
+       bool                    bar_mmap_supported[PCI_STD_NUM_BARS];
        u8                      *pci_config_map;
        u8                      *vconfig;
        struct perm_bits        *msi_perm;
-- 
2.21.0

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