From 0ba178888b05a4efdaca7da528c170bd09f9687b Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:24:51 +0800 Subject: powerpc/eeh: Remove reference to PCI device We will rely on pcibios_release_device() to remove the EEH cache and unbind EEH device for the specific PCI device. So we shouldn't hold the reference to the PCI device from EEH cache and EEH device. Otherwise, pcibios_release_device() won't be called as we expected. The patch removes the reference to the PCI device in EEH core. Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/eeh.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'arch/powerpc/kernel/eeh.c') diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 39954fe941b..b5c425ea297 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -499,8 +499,6 @@ unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned lon } eeh_dev_check_failure(edev); - - pci_dev_put(eeh_dev_to_pci_dev(edev)); return val; } @@ -904,7 +902,6 @@ static void eeh_add_device_late(struct pci_dev *dev) } WARN_ON(edev->pdev); - pci_dev_get(dev); edev->pdev = dev; dev->dev.archdata.edev = edev; @@ -992,7 +989,6 @@ static void eeh_remove_device(struct pci_dev *dev, int purge_pe) } edev->pdev = NULL; dev->dev.archdata.edev = NULL; - pci_dev_put(dev); eeh_rmv_from_parent_pe(edev, purge_pe); eeh_addr_cache_rmv_dev(dev); -- cgit v1.2.3-70-g09d2 From f2856491d24044de08da9e53cf7068841a8b4e1c Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:24:52 +0800 Subject: powerpc/eeh: Export functions for hotplug Make some functions public in order to support hotplug on either specific PCI bus or PCI device in future. Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/eeh.h | 9 +++++++++ arch/powerpc/kernel/eeh.c | 6 +++--- 2 files changed, 12 insertions(+), 3 deletions(-) (limited to 'arch/powerpc/kernel/eeh.c') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 09a8743143f..d9d35c27de2 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -209,9 +209,12 @@ unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val); int eeh_dev_check_failure(struct eeh_dev *edev); void eeh_addr_cache_build(void); +void eeh_add_device_early(struct device_node *); void eeh_add_device_tree_early(struct device_node *); +void eeh_add_device_late(struct pci_dev *); void eeh_add_device_tree_late(struct pci_bus *); void eeh_add_sysfs_files(struct pci_bus *); +void eeh_remove_device(struct pci_dev *, int); void eeh_remove_bus_device(struct pci_dev *, int); /** @@ -252,12 +255,18 @@ static inline unsigned long eeh_check_failure(const volatile void __iomem *token static inline void eeh_addr_cache_build(void) { } +static inline void eeh_add_device_early(struct device_node *dn) { } + static inline void eeh_add_device_tree_early(struct device_node *dn) { } +static inline void eeh_add_device_late(struct pci_dev *dev) { } + static inline void eeh_add_device_tree_late(struct pci_bus *bus) { } static inline void eeh_add_sysfs_files(struct pci_bus *bus) { } +static inline void eeh_remove_device(struct pci_dev *dev, int purge_pe) { } + static inline void eeh_remove_bus_device(struct pci_dev *dev, int purge_pe) { } #define EEH_POSSIBLE_ERROR(val, type) (0) diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index b5c425ea297..582ad1ef46a 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -836,7 +836,7 @@ core_initcall_sync(eeh_init); * on the CEC architecture, type of the device, on earlier boot * command-line arguments & etc. */ -static void eeh_add_device_early(struct device_node *dn) +void eeh_add_device_early(struct device_node *dn) { struct pci_controller *phb; @@ -884,7 +884,7 @@ EXPORT_SYMBOL_GPL(eeh_add_device_tree_early); * This routine must be used to complete EEH initialization for PCI * devices that were added after system boot (e.g. hotplug, dlpar). */ -static void eeh_add_device_late(struct pci_dev *dev) +void eeh_add_device_late(struct pci_dev *dev) { struct device_node *dn; struct eeh_dev *edev; @@ -972,7 +972,7 @@ EXPORT_SYMBOL_GPL(eeh_add_sysfs_files); * this device will no longer be detected after this call; thus, * i/o errors affecting this slot may leave this device unusable. */ -static void eeh_remove_device(struct pci_dev *dev, int purge_pe) +void eeh_remove_device(struct pci_dev *dev, int purge_pe) { struct eeh_dev *edev; -- cgit v1.2.3-70-g09d2 From 807a827d4e7455a40e8f56ec2a67c57a91cab9f7 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:24:55 +0800 Subject: powerpc/eeh: Keep PE during hotplug When we do normal hotplug, the PE (shadow EEH structure) shouldn't be kept around. However, we need to keep it if the hotplug an artifial one caused by EEH errors recovery. Since we remove EEH device through the PCI hook pcibios_release_device(), the flag "purge_pe" passed to various functions is meaningless. So the patch removes the meaningless flag and introduce new flag "EEH_PE_KEEP" to save the PE while doing hotplug during EEH error recovery. Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/eeh.h | 11 +++++------ arch/powerpc/include/asm/pci-bridge.h | 1 - arch/powerpc/kernel/eeh.c | 28 ++-------------------------- arch/powerpc/kernel/eeh_driver.c | 7 +++++-- arch/powerpc/kernel/eeh_pe.c | 7 +++---- arch/powerpc/kernel/pci-hotplug.c | 26 +++++--------------------- 6 files changed, 20 insertions(+), 60 deletions(-) (limited to 'arch/powerpc/kernel/eeh.c') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index d9d35c27de2..2ce22d7b71a 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -55,6 +55,8 @@ struct device_node; #define EEH_PE_RECOVERING (1 << 1) /* Recovering PE */ #define EEH_PE_PHB_DEAD (1 << 2) /* Dead PHB */ +#define EEH_PE_KEEP (1 << 8) /* Keep PE on hotplug */ + struct eeh_pe { int type; /* PE type: PHB/Bus/Device */ int state; /* PE EEH dependent mode */ @@ -193,7 +195,7 @@ int eeh_phb_pe_create(struct pci_controller *phb); struct eeh_pe *eeh_phb_pe_get(struct pci_controller *phb); struct eeh_pe *eeh_pe_get(struct eeh_dev *edev); int eeh_add_to_parent_pe(struct eeh_dev *edev); -int eeh_rmv_from_parent_pe(struct eeh_dev *edev, int purge_pe); +int eeh_rmv_from_parent_pe(struct eeh_dev *edev); void eeh_pe_update_time_stamp(struct eeh_pe *pe); void *eeh_pe_dev_traverse(struct eeh_pe *root, eeh_traverse_func fn, void *flag); @@ -214,8 +216,7 @@ void eeh_add_device_tree_early(struct device_node *); void eeh_add_device_late(struct pci_dev *); void eeh_add_device_tree_late(struct pci_bus *); void eeh_add_sysfs_files(struct pci_bus *); -void eeh_remove_device(struct pci_dev *, int); -void eeh_remove_bus_device(struct pci_dev *, int); +void eeh_remove_device(struct pci_dev *); /** * EEH_POSSIBLE_ERROR() -- test for possible MMIO failure. @@ -265,9 +266,7 @@ static inline void eeh_add_device_tree_late(struct pci_bus *bus) { } static inline void eeh_add_sysfs_files(struct pci_bus *bus) { } -static inline void eeh_remove_device(struct pci_dev *dev, int purge_pe) { } - -static inline void eeh_remove_bus_device(struct pci_dev *dev, int purge_pe) { } +static inline void eeh_remove_device(struct pci_dev *dev) { } #define EEH_POSSIBLE_ERROR(val, type) (0) #define EEH_IO_ERROR_VALUE(size) (-1UL) diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h index 2c1d8cb9b26..32d0d2018fa 100644 --- a/arch/powerpc/include/asm/pci-bridge.h +++ b/arch/powerpc/include/asm/pci-bridge.h @@ -209,7 +209,6 @@ static inline struct eeh_dev *of_node_to_eeh_dev(struct device_node *dn) extern struct pci_bus *pcibios_find_pci_bus(struct device_node *dn); /** Remove all of the PCI devices under this bus */ -extern void __pcibios_remove_pci_devices(struct pci_bus *bus, int purge_pe); extern void pcibios_remove_pci_devices(struct pci_bus *bus); /** Discover new pci devices under this bus, and add them */ diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 582ad1ef46a..ce81477316b 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -964,7 +964,6 @@ EXPORT_SYMBOL_GPL(eeh_add_sysfs_files); /** * eeh_remove_device - Undo EEH setup for the indicated pci device * @dev: pci device to be removed - * @purge_pe: remove the PE or not * * This routine should be called when a device is removed from * a running system (e.g. by hotplug or dlpar). It unregisters @@ -972,7 +971,7 @@ EXPORT_SYMBOL_GPL(eeh_add_sysfs_files); * this device will no longer be detected after this call; thus, * i/o errors affecting this slot may leave this device unusable. */ -void eeh_remove_device(struct pci_dev *dev, int purge_pe) +void eeh_remove_device(struct pci_dev *dev) { struct eeh_dev *edev; @@ -990,34 +989,11 @@ void eeh_remove_device(struct pci_dev *dev, int purge_pe) edev->pdev = NULL; dev->dev.archdata.edev = NULL; - eeh_rmv_from_parent_pe(edev, purge_pe); + eeh_rmv_from_parent_pe(edev); eeh_addr_cache_rmv_dev(dev); eeh_sysfs_remove_device(dev); } -/** - * eeh_remove_bus_device - Undo EEH setup for the indicated PCI device - * @dev: PCI device - * @purge_pe: remove the corresponding PE or not - * - * This routine must be called when a device is removed from the - * running system through hotplug or dlpar. The corresponding - * PCI address cache will be removed. - */ -void eeh_remove_bus_device(struct pci_dev *dev, int purge_pe) -{ - struct pci_bus *bus = dev->subordinate; - struct pci_dev *child, *tmp; - - eeh_remove_device(dev, purge_pe); - - if (bus && dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { - list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) - eeh_remove_bus_device(child, purge_pe); - } -} -EXPORT_SYMBOL_GPL(eeh_remove_bus_device); - static int proc_eeh_show(struct seq_file *m, void *v) { if (0 == eeh_subsystem_enabled) { diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index 2b1ce17cae5..9ef3bbb8580 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -362,8 +362,10 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus) * devices are expected to be attached soon when calling * into pcibios_add_pci_devices(). */ - if (bus) - __pcibios_remove_pci_devices(bus, 0); + if (bus) { + eeh_pe_state_mark(pe, EEH_PE_KEEP); + pcibios_remove_pci_devices(bus); + } /* Reset the pci controller. (Asserts RST#; resets config space). * Reconfigure bridges and devices. Don't try to bring the system @@ -386,6 +388,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus) if (bus) { ssleep(5); pcibios_add_pci_devices(bus); + eeh_pe_state_clear(pe, EEH_PE_KEEP); } pe->tstamp = tstamp; diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c index 016588a6f5e..32ef40940ba 100644 --- a/arch/powerpc/kernel/eeh_pe.c +++ b/arch/powerpc/kernel/eeh_pe.c @@ -333,7 +333,7 @@ int eeh_add_to_parent_pe(struct eeh_dev *edev) while (parent) { if (!(parent->type & EEH_PE_INVALID)) break; - parent->type &= ~EEH_PE_INVALID; + parent->type &= ~(EEH_PE_INVALID | EEH_PE_KEEP); parent = parent->parent; } pr_debug("EEH: Add %s to Device PE#%x, Parent PE#%x\n", @@ -397,14 +397,13 @@ int eeh_add_to_parent_pe(struct eeh_dev *edev) /** * eeh_rmv_from_parent_pe - Remove one EEH device from the associated PE * @edev: EEH device - * @purge_pe: remove PE or not * * The PE hierarchy tree might be changed when doing PCI hotplug. * Also, the PCI devices or buses could be removed from the system * during EEH recovery. So we have to call the function remove the * corresponding PE accordingly if necessary. */ -int eeh_rmv_from_parent_pe(struct eeh_dev *edev, int purge_pe) +int eeh_rmv_from_parent_pe(struct eeh_dev *edev) { struct eeh_pe *pe, *parent, *child; int cnt; @@ -431,7 +430,7 @@ int eeh_rmv_from_parent_pe(struct eeh_dev *edev, int purge_pe) if (pe->type & EEH_PE_PHB) break; - if (purge_pe) { + if (!(pe->state & EEH_PE_KEEP)) { if (list_empty(&pe->edevs) && list_empty(&pe->child_list)) { list_del(&pe->child); diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c index 3dab2f2801b..fc0831d4971 100644 --- a/arch/powerpc/kernel/pci-hotplug.c +++ b/arch/powerpc/kernel/pci-hotplug.c @@ -29,49 +29,33 @@ */ void pcibios_release_device(struct pci_dev *dev) { - eeh_remove_device(dev, 1); + eeh_remove_device(dev); } /** - * __pcibios_remove_pci_devices - remove all devices under this bus + * pcibios_remove_pci_devices - remove all devices under this bus * @bus: the indicated PCI bus - * @purge_pe: destroy the PE on removal of PCI devices * * Remove all of the PCI devices under this bus both from the * linux pci device tree, and from the powerpc EEH address cache. - * By default, the corresponding PE will be destroied during the - * normal PCI hotplug path. For PCI hotplug during EEH recovery, - * the corresponding PE won't be destroied and deallocated. */ -void __pcibios_remove_pci_devices(struct pci_bus *bus, int purge_pe) +void pcibios_remove_pci_devices(struct pci_bus *bus) { struct pci_dev *dev, *tmp; struct pci_bus *child_bus; /* First go down child busses */ list_for_each_entry(child_bus, &bus->children, node) - __pcibios_remove_pci_devices(child_bus, purge_pe); + pcibios_remove_pci_devices(child_bus); pr_debug("PCI: Removing devices on bus %04x:%02x\n", pci_domain_nr(bus), bus->number); list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) { - pr_debug(" * Removing %s...\n", pci_name(dev)); - eeh_remove_bus_device(dev, purge_pe); + pr_debug(" Removing %s...\n", pci_name(dev)); pci_stop_and_remove_bus_device(dev); } } -/** - * pcibios_remove_pci_devices - remove all devices under this bus - * @bus: the indicated PCI bus - * - * Remove all of the PCI devices under this bus both from the - * linux pci device tree, and from the powerpc EEH address cache. - */ -void pcibios_remove_pci_devices(struct pci_bus *bus) -{ - __pcibios_remove_pci_devices(bus, 1); -} EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices); /** -- cgit v1.2.3-70-g09d2 From 9feed42e93d2625db86423cedf8b4b2bed00779e Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:24:56 +0800 Subject: powerpc/eeh: Use safe list traversal when walking EEH devices Currently, we're trasversing the EEH devices list using list_for_each_entry(). That's not safe enough because the EEH devices might be removed from its parent PE while doing iteration. The patch replaces that with list_for_each_entry_safe(). Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/eeh.h | 4 ++-- arch/powerpc/kernel/eeh.c | 4 ++-- arch/powerpc/kernel/eeh_pe.c | 10 +++++----- 3 files changed, 9 insertions(+), 9 deletions(-) (limited to 'arch/powerpc/kernel/eeh.c') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 2ce22d7b71a..e8c411b63ca 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -74,8 +74,8 @@ struct eeh_pe { struct list_head child; /* Child PEs */ }; -#define eeh_pe_for_each_dev(pe, edev) \ - list_for_each_entry(edev, &pe->edevs, list) +#define eeh_pe_for_each_dev(pe, edev, tmp) \ + list_for_each_entry_safe(edev, tmp, &pe->edevs, list) /* * The struct is used to trace EEH state for the associated diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index ce81477316b..56bd4584f61 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -231,7 +231,7 @@ static size_t eeh_gather_pci_data(struct eeh_dev *edev, char * buf, size_t len) void eeh_slot_error_detail(struct eeh_pe *pe, int severity) { size_t loglen = 0; - struct eeh_dev *edev; + struct eeh_dev *edev, *tmp; bool valid_cfg_log = true; /* @@ -251,7 +251,7 @@ void eeh_slot_error_detail(struct eeh_pe *pe, int severity) eeh_pe_restore_bars(pe); pci_regs_buf[0] = 0; - eeh_pe_for_each_dev(pe, edev) { + eeh_pe_for_each_dev(pe, edev, tmp) { loglen += eeh_gather_pci_data(edev, pci_regs_buf + loglen, EEH_PCI_REGS_LOG_LEN - loglen); } diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c index 32ef40940ba..c8b815e45c8 100644 --- a/arch/powerpc/kernel/eeh_pe.c +++ b/arch/powerpc/kernel/eeh_pe.c @@ -176,7 +176,7 @@ void *eeh_pe_dev_traverse(struct eeh_pe *root, eeh_traverse_func fn, void *flag) { struct eeh_pe *pe; - struct eeh_dev *edev; + struct eeh_dev *edev, *tmp; void *ret; if (!root) { @@ -186,7 +186,7 @@ void *eeh_pe_dev_traverse(struct eeh_pe *root, /* Traverse root PE */ for (pe = root; pe; pe = eeh_pe_next(pe, root)) { - eeh_pe_for_each_dev(pe, edev) { + eeh_pe_for_each_dev(pe, edev, tmp) { ret = fn(edev, flag); if (ret) return ret; @@ -501,7 +501,7 @@ static void *__eeh_pe_state_mark(void *data, void *flag) { struct eeh_pe *pe = (struct eeh_pe *)data; int state = *((int *)flag); - struct eeh_dev *tmp; + struct eeh_dev *edev, *tmp; struct pci_dev *pdev; /* @@ -511,8 +511,8 @@ static void *__eeh_pe_state_mark(void *data, void *flag) * the PCI device driver. */ pe->state |= state; - eeh_pe_for_each_dev(pe, tmp) { - pdev = eeh_dev_to_pci_dev(tmp); + eeh_pe_for_each_dev(pe, edev, tmp) { + pdev = eeh_dev_to_pci_dev(edev); if (pdev) pdev->error_state = pci_channel_io_frozen; } -- cgit v1.2.3-70-g09d2 From f5c57710dd62dd06f176934a8b4b8accbf00f9f8 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Wed, 24 Jul 2013 10:24:58 +0800 Subject: powerpc/eeh: Use partial hotplug for EEH unaware drivers When EEH error happens to one specific PE, some devices with drivers supporting EEH won't except hotplug on the device. However, there might have other deivces without driver, or with driver without EEH support. For the case, we need do partial hotplug in order to make sure that the PE becomes absolutely quite during reset. Otherise, the PE reset might fail and leads to failure of error recovery. The current code doesn't handle that 'mixed' case properly, it either uses the error callbacks to the drivers, or tries hotplug, but doesn't handle a PE (EEH domain) composed of a combination of the two. The patch intends to support so-called "partial" hotplug for EEH: Before we do reset, we stop and remove those PCI devices without EEH sensitive driver. The corresponding EEH devices are not detached from its PE, but with special flag. After the reset is done, those EEH devices with the special flag will be scanned one by one. Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/eeh.h | 6 ++- arch/powerpc/kernel/eeh.c | 30 +++++++++-- arch/powerpc/kernel/eeh_driver.c | 74 ++++++++++++++++++++++++++-- arch/powerpc/kernel/eeh_pe.c | 20 +++----- arch/powerpc/kernel/eeh_sysfs.c | 7 +++ arch/powerpc/platforms/powernv/eeh-powernv.c | 2 +- arch/powerpc/platforms/pseries/eeh_pseries.c | 2 +- 7 files changed, 117 insertions(+), 24 deletions(-) (limited to 'arch/powerpc/kernel/eeh.c') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index e8c411b63ca..f54a60131de 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -84,7 +84,8 @@ struct eeh_pe { * another tree except the currently existing tree of PCI * buses and PCI devices */ -#define EEH_DEV_IRQ_DISABLED (1<<0) /* Interrupt disabled */ +#define EEH_DEV_IRQ_DISABLED (1 << 0) /* Interrupt disabled */ +#define EEH_DEV_DISCONNECTED (1 << 1) /* Removing from PE */ struct eeh_dev { int mode; /* EEH mode */ @@ -97,6 +98,7 @@ struct eeh_dev { struct pci_controller *phb; /* Associated PHB */ struct device_node *dn; /* Associated device node */ struct pci_dev *pdev; /* Associated PCI device */ + struct pci_bus *bus; /* PCI bus for partial hotplug */ }; static inline struct device_node *eeh_dev_to_of_node(struct eeh_dev *edev) @@ -197,6 +199,8 @@ struct eeh_pe *eeh_pe_get(struct eeh_dev *edev); int eeh_add_to_parent_pe(struct eeh_dev *edev); int eeh_rmv_from_parent_pe(struct eeh_dev *edev); void eeh_pe_update_time_stamp(struct eeh_pe *pe); +void *eeh_pe_traverse(struct eeh_pe *root, + eeh_traverse_func fn, void *flag); void *eeh_pe_dev_traverse(struct eeh_pe *root, eeh_traverse_func fn, void *flag); void eeh_pe_restore_bars(struct eeh_pe *pe); diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 56bd4584f61..a5783f1a7a9 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -900,7 +900,21 @@ void eeh_add_device_late(struct pci_dev *dev) pr_debug("EEH: Already referenced !\n"); return; } - WARN_ON(edev->pdev); + + /* + * The EEH cache might not be removed correctly because of + * unbalanced kref to the device during unplug time, which + * relies on pcibios_release_device(). So we have to remove + * that here explicitly. + */ + if (edev->pdev) { + eeh_rmv_from_parent_pe(edev); + eeh_addr_cache_rmv_dev(edev->pdev); + eeh_sysfs_remove_device(edev->pdev); + + edev->pdev = NULL; + dev->dev.archdata.edev = NULL; + } edev->pdev = dev; dev->dev.archdata.edev = edev; @@ -982,14 +996,24 @@ void eeh_remove_device(struct pci_dev *dev) /* Unregister the device with the EEH/PCI address search system */ pr_debug("EEH: Removing device %s\n", pci_name(dev)); - if (!edev || !edev->pdev) { + if (!edev || !edev->pdev || !edev->pe) { pr_debug("EEH: Not referenced !\n"); return; } + + /* + * During the hotplug for EEH error recovery, we need the EEH + * device attached to the parent PE in order for BAR restore + * a bit later. So we keep it for BAR restore and remove it + * from the parent PE during the BAR resotre. + */ edev->pdev = NULL; dev->dev.archdata.edev = NULL; + if (!(edev->pe->state & EEH_PE_KEEP)) + eeh_rmv_from_parent_pe(edev); + else + edev->mode |= EEH_DEV_DISCONNECTED; - eeh_rmv_from_parent_pe(edev); eeh_addr_cache_rmv_dev(dev); eeh_sysfs_remove_device(dev); } diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index 9ef3bbb8580..9fda75d1f5a 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -338,6 +338,54 @@ static void *eeh_report_failure(void *data, void *userdata) return NULL; } +static void *eeh_rmv_device(void *data, void *userdata) +{ + struct pci_driver *driver; + struct eeh_dev *edev = (struct eeh_dev *)data; + struct pci_dev *dev = eeh_dev_to_pci_dev(edev); + int *removed = (int *)userdata; + + /* + * Actually, we should remove the PCI bridges as well. + * However, that's lots of complexity to do that, + * particularly some of devices under the bridge might + * support EEH. So we just care about PCI devices for + * simplicity here. + */ + if (!dev || (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)) + return NULL; + driver = eeh_pcid_get(dev); + if (driver && driver->err_handler) + return NULL; + + /* Remove it from PCI subsystem */ + pr_debug("EEH: Removing %s without EEH sensitive driver\n", + pci_name(dev)); + edev->bus = dev->bus; + edev->mode |= EEH_DEV_DISCONNECTED; + (*removed)++; + + pci_stop_and_remove_bus_device(dev); + + return NULL; +} + +static void *eeh_pe_detach_dev(void *data, void *userdata) +{ + struct eeh_pe *pe = (struct eeh_pe *)data; + struct eeh_dev *edev, *tmp; + + eeh_pe_for_each_dev(pe, edev, tmp) { + if (!(edev->mode & EEH_DEV_DISCONNECTED)) + continue; + + edev->mode &= ~(EEH_DEV_DISCONNECTED | EEH_DEV_IRQ_DISABLED); + eeh_rmv_from_parent_pe(edev); + } + + return NULL; +} + /** * eeh_reset_device - Perform actual reset of a pci slot * @pe: EEH PE @@ -349,8 +397,9 @@ static void *eeh_report_failure(void *data, void *userdata) */ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus) { + struct pci_bus *frozen_bus = eeh_pe_bus_get(pe); struct timeval tstamp; - int cnt, rc; + int cnt, rc, removed = 0; /* pcibios will clear the counter; save the value */ cnt = pe->freeze_count; @@ -362,10 +411,11 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus) * devices are expected to be attached soon when calling * into pcibios_add_pci_devices(). */ - if (bus) { - eeh_pe_state_mark(pe, EEH_PE_KEEP); + eeh_pe_state_mark(pe, EEH_PE_KEEP); + if (bus) pcibios_remove_pci_devices(bus); - } + else if (frozen_bus) + eeh_pe_dev_traverse(pe, eeh_rmv_device, &removed); /* Reset the pci controller. (Asserts RST#; resets config space). * Reconfigure bridges and devices. Don't try to bring the system @@ -386,10 +436,24 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus) * potentially weird things happen. */ if (bus) { + pr_info("EEH: Sleep 5s ahead of complete hotplug\n"); ssleep(5); + + /* + * The EEH device is still connected with its parent + * PE. We should disconnect it so the binding can be + * rebuilt when adding PCI devices. + */ + eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL); pcibios_add_pci_devices(bus); - eeh_pe_state_clear(pe, EEH_PE_KEEP); + } else if (frozen_bus && removed) { + pr_info("EEH: Sleep 5s ahead of partial hotplug\n"); + ssleep(5); + + eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL); + pcibios_add_pci_devices(frozen_bus); } + eeh_pe_state_clear(pe, EEH_PE_KEEP); pe->tstamp = tstamp; pe->freeze_count = cnt; diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c index c8b815e45c8..2aa955ae01a 100644 --- a/arch/powerpc/kernel/eeh_pe.c +++ b/arch/powerpc/kernel/eeh_pe.c @@ -149,8 +149,8 @@ static struct eeh_pe *eeh_pe_next(struct eeh_pe *pe, * callback returns something other than NULL, or no more PEs * to be traversed. */ -static void *eeh_pe_traverse(struct eeh_pe *root, - eeh_traverse_func fn, void *flag) +void *eeh_pe_traverse(struct eeh_pe *root, + eeh_traverse_func fn, void *flag) { struct eeh_pe *pe; void *ret; @@ -409,8 +409,8 @@ int eeh_rmv_from_parent_pe(struct eeh_dev *edev) int cnt; if (!edev->pe) { - pr_warning("%s: No PE found for EEH device %s\n", - __func__, edev->dn->full_name); + pr_debug("%s: No PE found for EEH device %s\n", + __func__, edev->dn->full_name); return -EEXIST; } @@ -728,18 +728,12 @@ static void eeh_restore_device_bars(struct eeh_dev *edev, */ static void *eeh_restore_one_device_bars(void *data, void *flag) { - struct pci_dev *pdev = NULL; struct eeh_dev *edev = (struct eeh_dev *)data; + struct pci_dev *pdev = eeh_dev_to_pci_dev(edev); struct device_node *dn = eeh_dev_to_of_node(edev); - /* Trace the PCI bridge */ - if (eeh_probe_mode_dev()) { - pdev = eeh_dev_to_pci_dev(edev); - if (pdev->hdr_type != PCI_HEADER_TYPE_BRIDGE) - pdev = NULL; - } - - if (pdev) + /* Do special restore for bridges */ + if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE) eeh_restore_bridge_bars(pdev, edev, dn); else eeh_restore_device_bars(edev, dn); diff --git a/arch/powerpc/kernel/eeh_sysfs.c b/arch/powerpc/kernel/eeh_sysfs.c index e7ae3484918..61e2a145213 100644 --- a/arch/powerpc/kernel/eeh_sysfs.c +++ b/arch/powerpc/kernel/eeh_sysfs.c @@ -68,6 +68,13 @@ void eeh_sysfs_add_device(struct pci_dev *pdev) void eeh_sysfs_remove_device(struct pci_dev *pdev) { + /* + * The parent directory might have been removed. We needn't + * continue for that case. + */ + if (!pdev->dev.kobj.sd) + 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); diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index 969cce73055..a380428cf9c 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -114,7 +114,7 @@ static int powernv_eeh_dev_probe(struct pci_dev *dev, void *flag) * the root bridge. So it's not reasonable to continue * the probing. */ - if (!dn || !edev) + if (!dn || !edev || edev->pe) return 0; /* Skip for PCI-ISA bridge */ diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c index b456b157d33..0f44f9fe49a 100644 --- a/arch/powerpc/platforms/pseries/eeh_pseries.c +++ b/arch/powerpc/platforms/pseries/eeh_pseries.c @@ -153,7 +153,7 @@ static void *pseries_eeh_of_probe(struct device_node *dn, void *flag) /* Retrieve OF node and eeh device */ edev = of_node_to_eeh_dev(dn); - if (!of_device_is_available(dn)) + if (edev->pe || !of_device_is_available(dn)) return NULL; /* Retrieve class/vendor/device IDs */ -- cgit v1.2.3-70-g09d2 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/kernel/eeh.c') diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 4199d994327..d3e5e9bc8f9 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 a5783f1a7a9..ea9414c8088 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 61e2a145213..5d753d4f2c7 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 4361a5c7f3a..79663d26e6e 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 9e80f0af311..7fbc25b1813 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 v1.2.3-70-g09d2