Patchwork [v2] pci: fix pci_find_bus().

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Submitter Isaku Yamahata
Date April 12, 2010, 2:58 a.m.
Message ID <20100412025859.GD1232@valinux.co.jp>
Download mbox | patch
Permalink /patch/49937/
State New
Headers show

Comments

Isaku Yamahata - April 12, 2010, 2:58 a.m.
When looking down child bus, it should look parent bridge's
bus number, not child bus's.
Optimized tail recursion and style fix.

Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
---
 hw/pci.c |   25 ++++++++++++++++---------
 1 files changed, 16 insertions(+), 9 deletions(-)
Blue Swirl - April 20, 2010, 5:19 p.m.
Thanks, applied.

On 4/12/10, Isaku Yamahata <yamahata@valinux.co.jp> wrote:
> When looking down child bus, it should look parent bridge's
>  bus number, not child bus's.
>
> Optimized tail recursion and style fix.
>
>
>  Cc: Blue Swirl <blauwirbel@gmail.com>
>  Cc: "Michael S. Tsirkin" <mst@redhat.com>
>  Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
>  ---
>
>  hw/pci.c |   25 ++++++++++++++++---------
>   1 files changed, 16 insertions(+), 9 deletions(-)
>
>
>  diff --git a/hw/pci.c b/hw/pci.c
>
> index 2355232..6c0cc7b 100644
>
> --- a/hw/pci.c
>  +++ b/hw/pci.c
>
> @@ -1546,23 +1546,30 @@ static void pci_bridge_write_config(PCIDevice *d,
>
>
>   PCIBus *pci_find_bus(PCIBus *bus, int bus_num)
>
>  {
>  -    PCIBus *sec, *ret;
>  +    PCIBus *sec;
>
>
> -    if (!bus)
>  +    if (!bus) {
>          return NULL;
>  +    }
>
>
>      if (pci_bus_num(bus) == bus_num) {
>          return bus;
>
>      }
>
>      /* try child bus */
>  -    QLIST_FOREACH(sec, &bus->child, sibling) {
>  -        if (!bus->parent_dev /* pci host bridge */
>  -            || (pci_bus_num(sec) <= bus_num &&
>  -                bus_num <= bus->parent_dev->config[PCI_SUBORDINATE_BUS]) ) {
>
> -            ret = pci_find_bus(sec, bus_num);
>  -            if (ret) {
>  -                return ret;
>  +    if (!bus->parent_dev /* host pci bridge */ ||
>  +        (bus->parent_dev->config[PCI_SECONDARY_BUS] < bus_num &&
>
> +         bus_num <= bus->parent_dev->config[PCI_SUBORDINATE_BUS])) {
>
> +        for (; bus; bus = sec) {
>
> +            QLIST_FOREACH(sec, &bus->child, sibling) {
>
> +                assert(sec->parent_dev);
>  +                if (sec->parent_dev->config[PCI_SECONDARY_BUS] == bus_num) {
>  +                    return sec;
>  +                }
>  +                if (sec->parent_dev->config[PCI_SECONDARY_BUS] < bus_num &&
>
> +                    bus_num <= sec->parent_dev->config[PCI_SUBORDINATE_BUS]) {
>  +                    break;
>  +                }
>              }
>          }
>      }
>
> --
>  1.6.6.1
>
>
>

Patch

diff --git a/hw/pci.c b/hw/pci.c
index 2355232..6c0cc7b 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -1546,23 +1546,30 @@  static void pci_bridge_write_config(PCIDevice *d,
 
 PCIBus *pci_find_bus(PCIBus *bus, int bus_num)
 {
-    PCIBus *sec, *ret;
+    PCIBus *sec;
 
-    if (!bus)
+    if (!bus) {
         return NULL;
+    }
 
     if (pci_bus_num(bus) == bus_num) {
         return bus;
     }
 
     /* try child bus */
-    QLIST_FOREACH(sec, &bus->child, sibling) {
-        if (!bus->parent_dev /* pci host bridge */
-            || (pci_bus_num(sec) <= bus_num &&
-                bus_num <= bus->parent_dev->config[PCI_SUBORDINATE_BUS]) ) {
-            ret = pci_find_bus(sec, bus_num);
-            if (ret) {
-                return ret;
+    if (!bus->parent_dev /* host pci bridge */ ||
+        (bus->parent_dev->config[PCI_SECONDARY_BUS] < bus_num &&
+         bus_num <= bus->parent_dev->config[PCI_SUBORDINATE_BUS])) {
+        for (; bus; bus = sec) {
+            QLIST_FOREACH(sec, &bus->child, sibling) {
+                assert(sec->parent_dev);
+                if (sec->parent_dev->config[PCI_SECONDARY_BUS] == bus_num) {
+                    return sec;
+                }
+                if (sec->parent_dev->config[PCI_SECONDARY_BUS] < bus_num &&
+                    bus_num <= sec->parent_dev->config[PCI_SUBORDINATE_BUS]) {
+                    break;
+                }
             }
         }
     }