Re: [PATCH kernel 5/5] powerpc/eeh: Remove unnecessary node from pci_dn
From: Andrew Donnellan <hidden>
Date: 2017-08-24 05:20:03
On 23/08/17 20:19, Alexey Kardashevskiy wrote:
The pci_dn struct caches a OF device node pointer in order to access the "ibm,loc-code" property when EEH is recovering. However, when this happens in eeh_dev_check_failure(), we also have a pci_dev pointer which should have a valid pointer to the device node when pci_dn has one (both pointers are not NULL for physical functions and are NULL for virtual functions). This removes the node pointer from the pci_dn struct and used pdev in eeh_dev_check_failure() instead. This changes pci_remove_device_node_info() to look for a parent of the node being removed, just like pci_add_device_node_info() does when it references the parent node. Signed-off-by: Alexey Kardashevskiy <redacted>
Reviewed-by: Andrew Donnellan <redacted>
quoted hunk
--- arch/powerpc/include/asm/pci-bridge.h | 1 - arch/powerpc/kernel/eeh.c | 9 +++++---- arch/powerpc/kernel/pci_dn.c | 8 +++++--- 3 files changed, 10 insertions(+), 8 deletions(-)diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h index 56c67d3f0108..0b8aa1fe2d5f 100644 --- a/arch/powerpc/include/asm/pci-bridge.h +++ b/arch/powerpc/include/asm/pci-bridge.h@@ -195,7 +195,6 @@ struct pci_dn { struct pci_dn *parent; struct pci_controller *phb; /* for pci devices */ struct iommu_table_group *table_group; /* for phb's or bridges */ - struct device_node *node; /* back-pointer to the device_node */ int pci_ext_config_space; /* for pci devices */diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index c877014d11ce..2c926029adbe 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c@@ -435,7 +435,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev) int ret; int active_flags = (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE); unsigned long flags; - struct pci_dn *pdn; + struct device_node *dn; struct pci_dev *dev; struct eeh_pe *pe, *parent_pe, *phb_pe; int rc = 0;@@ -493,9 +493,10 @@ int eeh_dev_check_failure(struct eeh_dev *edev) if (pe->state & EEH_PE_ISOLATED) { pe->check_count++; if (pe->check_count % EEH_MAX_FAILS == 0) { - pdn = eeh_dev_to_pdn(edev); - if (pdn->node) - location = of_get_property(pdn->node, "ibm,loc-code", NULL); + dn = pci_device_to_OF_node(dev); + if (dn) + location = of_get_property(dn, "ibm,loc-code", + NULL); printk(KERN_ERR "EEH: %d reads ignored for recovering device at " "location=%s driver=%s pci addr=%s\n", pe->check_count,diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c index 0256372b72de..0e395afbf0f4 100644 --- a/arch/powerpc/kernel/pci_dn.c +++ b/arch/powerpc/kernel/pci_dn.c@@ -293,7 +293,6 @@ struct pci_dn *pci_add_device_node_info(struct pci_controller *hose, if (pdn == NULL) return NULL; dn->data = pdn; - pdn->node = dn; pdn->phb = hose; #ifdef CONFIG_PPC_POWERNV pdn->pe_number = IODA_INVALID_PE;@@ -342,6 +341,7 @@ EXPORT_SYMBOL_GPL(pci_add_device_node_info); void pci_remove_device_node_info(struct device_node *dn) { struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL; + struct device_node *parent; #ifdef CONFIG_EEH struct eeh_dev *edev = pdn_to_eeh_dev(pdn);@@ -354,8 +354,10 @@ void pci_remove_device_node_info(struct device_node *dn) WARN_ON(!list_empty(&pdn->child_list)); list_del(&pdn->list); - if (pdn->parent) - of_node_put(pdn->parent->node); + + parent = of_get_parent(dn); + if (parent) + of_node_put(parent); dn->data = NULL; kfree(pdn);
-- Andrew Donnellan OzLabs, ADL Canberra andrew.donnellan@au1.ibm.com IBM Australia Limited