On Fri, Oct 30, 2015 at 02:22:43PM +1100, Alexey Kardashevskiy wrote:

On 10/26/2015 02:15 PM, Wei Yang wrote:

quoted

EEH address cache, which helps to locate the PCI device according to
the given (physical) MMIO address, didn't cover PCI bridges. Also, it
shouldn't return PF

"it shouldn't return" is about the cache, right? eeh_addr_cache_get_dev() -
this guy can "return", the cache cannot.

Here I want to say if we cache the PF's IOV BAR, eeh_addr_cache_get_dev()
would return PF when the address is for VF.

quoted

with address in PF's IOV BARs. Instead, the VFs
should be returned.

Also, by doing so, it removes the type check in
eeh_addr_cache_insert_dev(), since bridge's window would not be cached.

The patch restricts the address cache to cover first 7 BARs for the
above purposes.

I'd better understand something like this :)

This restricts the EEH address cache to use only first 7 BARs. This makes
__eeh_addr_cache_insert_dev() ignore PCI bridge windows and IOV BARs. As the
result of this change, eeh_addr_cache_get_dev() will return VFs from VF's
resource addresses instead of parent PFs.

This removes extra check for a PCI bridge as we limit
__eeh_addr_cache_insert_dev() to 7 BARs and this effectively excludes PCI
bridges from being cached.

Yep, I think this one is more clear. Would use this one.

quoted

[gwshan: changelog]
Signed-off-by: Wei Yang <redacted>
Acked-by: Gavin Shan <redacted>
---
 arch/powerpc/kernel/eeh_cache.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/eeh_cache.c b/arch/powerpc/kernel/eeh_cache.c
index a1e86e1..e6887f0 100644
--- a/arch/powerpc/kernel/eeh_cache.c
+++ b/arch/powerpc/kernel/eeh_cache.c

@@ -196,7 +196,7 @@ static void __eeh_addr_cache_insert_dev(struct pci_dev *dev)
 	}

 	/* Walk resources on this device, poke them into the tree */
-	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
 		resource_size_t start = pci_resource_start(dev,i);
 		resource_size_t end = pci_resource_end(dev,i);
 		unsigned long flags = pci_resource_flags(dev,i);

@@ -222,10 +222,6 @@ void eeh_addr_cache_insert_dev(struct pci_dev *dev)
 {
 	unsigned long flags;

-	/* Ignore PCI bridges */
-	if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
-		return;
-
 	spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
 	__eeh_addr_cache_insert_dev(dev);
 	spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);

-- 
Alexey

-- 
Richard Yang
Help you, Help me