From ab55d2187da27414f78056810713c92f9a4350c2 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:25:01 +0800 Subject: powerpc/eeh: Introdce flag to protect sysfs The patch introduces flag EEH_DEV_SYSFS to keep track that the sysfs entries for the corresponding EEH device (then PCI device) has been added or removed, in order to avoid race condition. Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/eeh.h | 2 ++ arch/powerpc/kernel/eeh.c | 2 ++ arch/powerpc/kernel/eeh_sysfs.c | 16 +++++++++++++++- arch/powerpc/platforms/powernv/eeh-powernv.c | 4 ++-- arch/powerpc/platforms/pseries/eeh_pseries.c | 2 +- 5 files changed, 22 insertions(+), 4 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 4199d9943277..d3e5e9bc8f94 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -90,6 +90,8 @@ struct eeh_pe { #define EEH_DEV_IRQ_DISABLED (1 << 3) /* Interrupt disabled */ #define EEH_DEV_DISCONNECTED (1 << 4) /* Removing from PE */ +#define EEH_DEV_SYSFS (1 << 8) /* Sysfs created */ + struct eeh_dev { int mode; /* EEH mode */ int class_code; /* Class code of the device */ diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index a5783f1a7a96..ea9414c8088d 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -911,6 +911,7 @@ void eeh_add_device_late(struct pci_dev *dev) eeh_rmv_from_parent_pe(edev); eeh_addr_cache_rmv_dev(edev->pdev); eeh_sysfs_remove_device(edev->pdev); + edev->mode &= ~EEH_DEV_SYSFS; edev->pdev = NULL; dev->dev.archdata.edev = NULL; @@ -1016,6 +1017,7 @@ void eeh_remove_device(struct pci_dev *dev) eeh_addr_cache_rmv_dev(dev); eeh_sysfs_remove_device(dev); + edev->mode &= ~EEH_DEV_SYSFS; } static int proc_eeh_show(struct seq_file *m, void *v) diff --git a/arch/powerpc/kernel/eeh_sysfs.c b/arch/powerpc/kernel/eeh_sysfs.c index 61e2a1452131..5d753d4f2c75 100644 --- a/arch/powerpc/kernel/eeh_sysfs.c +++ b/arch/powerpc/kernel/eeh_sysfs.c @@ -56,26 +56,40 @@ EEH_SHOW_ATTR(eeh_pe_config_addr, pe_config_addr, "0x%x"); void eeh_sysfs_add_device(struct pci_dev *pdev) { + struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev); int rc=0; + if (edev && (edev->mode & EEH_DEV_SYSFS)) + return; + rc += device_create_file(&pdev->dev, &dev_attr_eeh_mode); rc += device_create_file(&pdev->dev, &dev_attr_eeh_config_addr); rc += device_create_file(&pdev->dev, &dev_attr_eeh_pe_config_addr); if (rc) printk(KERN_WARNING "EEH: Unable to create sysfs entries\n"); + else if (edev) + edev->mode |= EEH_DEV_SYSFS; } void eeh_sysfs_remove_device(struct pci_dev *pdev) { + struct eeh_dev *edev = pci_dev_to_eeh_dev(pdev); + /* * The parent directory might have been removed. We needn't * continue for that case. */ - if (!pdev->dev.kobj.sd) + if (!pdev->dev.kobj.sd) { + if (edev) + edev->mode &= ~EEH_DEV_SYSFS; return; + } device_remove_file(&pdev->dev, &dev_attr_eeh_mode); device_remove_file(&pdev->dev, &dev_attr_eeh_config_addr); device_remove_file(&pdev->dev, &dev_attr_eeh_pe_config_addr); + + if (edev) + edev->mode &= ~EEH_DEV_SYSFS; } diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index 4361a5c7f3ab..79663d26e6ea 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -122,8 +122,8 @@ static int powernv_eeh_dev_probe(struct pci_dev *dev, void *flag) return 0; /* Initialize eeh device */ - edev->class_code = dev->class; - edev->mode = 0; + edev->class_code = dev->class; + edev->mode &= 0xFFFFFF00; if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) edev->mode |= EEH_DEV_BRIDGE; if (pci_is_pcie(dev)) { diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c index 9e80f0af311f..7fbc25b1813f 100644 --- a/arch/powerpc/platforms/pseries/eeh_pseries.c +++ b/arch/powerpc/platforms/pseries/eeh_pseries.c @@ -218,7 +218,7 @@ static void *pseries_eeh_of_probe(struct device_node *dn, void *flag) */ edev->class_code = *class_code; edev->pcie_cap = pseries_eeh_find_cap(dn, PCI_CAP_ID_EXP); - edev->mode = 0; + edev->mode &= 0xFFFFFF00; if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) { edev->mode |= EEH_DEV_BRIDGE; if (edev->pcie_cap) { -- cgit v1.2.3