Commit e86350f7 authored by Oliver O'Halloran's avatar Oliver O'Halloran Committed by Michael Ellerman
Browse files

powerpc/eeh: Rework eeh_ops->probe() 



With the EEH early probe now being pseries specific there's no need for
eeh_ops->probe() to take a pci_dn. Instead, we can make it take a pci_dev
and use the probe function to map a pci_dev to an eeh_dev. This allows
the platform to implement it's own method for finding (or creating) an
eeh_dev for a given pci_dev which also removes a use of pci_dn in
generic EEH code.

This patch also renames eeh_device_add_late() to eeh_device_probe(). This
better reflects what it does does and removes the last vestiges of the
early/late EEH probe split.

Reviewed-by: default avatarSam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: default avatarOliver O'Halloran <oohall@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-6-oohall@gmail.com
parent b6eebb09

arch/powerpc/include/asm/eeh.h

+3 −3
Original line number Diff line number Diff line
@@ -215,7 +215,7 @@ enum { 
struct eeh_ops {

	char *name;

	int (*init)(void);

	void* (*probe)(struct pci_dn *pdn, void *data);

	struct eeh_dev *(*probe)(struct pci_dev *pdev);

	int (*set_option)(struct eeh_pe *pe, int option);

	int (*get_pe_addr)(struct eeh_pe *pe);

	int (*get_state)(struct eeh_pe *pe, int *delay);
@@ -301,7 +301,7 @@ int __exit eeh_ops_unregister(const char *name); 
int eeh_check_failure(const volatile void __iomem *token);

int eeh_dev_check_failure(struct eeh_dev *edev);

void eeh_addr_cache_init(void);

void eeh_add_device_late(struct pci_dev *);

void eeh_probe_device(struct pci_dev *pdev);

void eeh_remove_device(struct pci_dev *);

int eeh_unfreeze_pe(struct eeh_pe *pe);

int eeh_pe_reset_and_recover(struct eeh_pe *pe);
@@ -356,7 +356,7 @@ static inline int eeh_check_failure(const volatile void __iomem *token) 


static inline void eeh_addr_cache_init(void) { }



static inline void eeh_add_device_late(struct pci_dev *dev) { }

static inline void eeh_probe_device(struct pci_dev *dev) { }



static inline void eeh_remove_device(struct pci_dev *dev) { }

arch/powerpc/kernel/eeh.c

+23 −21
Original line number Diff line number Diff line
@@ -1107,35 +1107,43 @@ static int eeh_init(void) 
core_initcall_sync(eeh_init);



/**

 * eeh_add_device_late - Perform EEH initialization for the indicated pci device

 * eeh_probe_device() - Perform EEH initialization for the indicated pci device

 * @dev: pci device for which to set up EEH

 *

 * This routine must be used to complete EEH initialization for PCI

 * devices that were added after system boot (e.g. hotplug, dlpar).

 */

void eeh_add_device_late(struct pci_dev *dev)

void eeh_probe_device(struct pci_dev *dev)

{

	struct pci_dn *pdn;

	struct eeh_dev *edev;



	if (!dev)

	pr_debug("EEH: Adding device %s\n", pci_name(dev));



	/*

	 * pci_dev_to_eeh_dev() can only work if eeh_probe_dev() was

	 * already called for this device.

	 */

	if (WARN_ON_ONCE(pci_dev_to_eeh_dev(dev))) {

		pci_dbg(dev, "Already bound to an eeh_dev!\n");

		return;

	}



	pdn = pci_get_pdn_by_devfn(dev->bus, dev->devfn);

	edev = pdn_to_eeh_dev(pdn);

	eeh_edev_dbg(edev, "Adding device\n");

	if (edev->pdev == dev) {

		eeh_edev_dbg(edev, "Device already referenced!\n");

	edev = eeh_ops->probe(dev);

	if (!edev) {

		pr_debug("EEH: Adding device failed\n");

		return;

	}



	/*

	 * 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.

	 * FIXME: We rely on pcibios_release_device() to remove the

	 * existing EEH state. The release function is only called if

	 * the pci_dev's refcount drops to zero so if something is

	 * keeping a ref to a device (e.g. a filesystem) we need to

	 * remove the old EEH state.

	 *

	 * FIXME: HEY MA, LOOK AT ME, NO LOCKING!

	 */

	if (edev->pdev) {

	if (edev->pdev && edev->pdev != dev) {

		eeh_rmv_from_parent_pe(edev);

		eeh_addr_cache_rmv_dev(edev->pdev);

		eeh_sysfs_remove_device(edev->pdev);
@@ -1146,17 +1154,11 @@ void eeh_add_device_late(struct pci_dev *dev) 
		 * into error handler afterwards.

		 */

		edev->mode |= EEH_DEV_NO_HANDLER;



		edev->pdev = NULL;

		dev->dev.archdata.edev = NULL;

	}



	if (eeh_has_flag(EEH_PROBE_MODE_DEV))

		eeh_ops->probe(pdn, NULL);



	/* bind the pdev and the edev together */

	edev->pdev = dev;

	dev->dev.archdata.edev = edev;



	eeh_addr_cache_insert_dev(dev);

	eeh_sysfs_add_device(dev);

}

arch/powerpc/platforms/powernv/eeh-powernv.c

+14 −16
Original line number Diff line number Diff line
@@ -41,7 +41,7 @@ static int eeh_event_irq = -EINVAL; 
void pnv_pcibios_bus_add_device(struct pci_dev *pdev)

{

	dev_dbg(&pdev->dev, "EEH: Setting up device\n");

	eeh_add_device_late(pdev);

	eeh_probe_device(pdev);

}



static int pnv_eeh_init(void)
@@ -340,23 +340,13 @@ static int pnv_eeh_find_ecap(struct pci_dn *pdn, int cap) 


/**

 * pnv_eeh_probe - Do probe on PCI device

 * @pdn: PCI device node

 * @data: unused

 * @pdev: pci_dev to probe

 *

 * When EEH module is installed during system boot, all PCI devices

 * are checked one by one to see if it supports EEH. The function

 * is introduced for the purpose. By default, EEH has been enabled

 * on all PCI devices. That's to say, we only need do necessary

 * initialization on the corresponding eeh device and create PE

 * accordingly.

 *

 * It's notable that's unsafe to retrieve the EEH device through

 * the corresponding PCI device. During the PCI device hotplug, which

 * was possiblly triggered by EEH core, the binding between EEH device

 * and the PCI device isn't built yet.

 * Create, or find the existing, eeh_dev for this pci_dev.

 */

static void *pnv_eeh_probe(struct pci_dn *pdn, void *data)

static struct eeh_dev *pnv_eeh_probe(struct pci_dev *pdev)

{

	struct pci_dn *pdn = pci_get_pdn(pdev);

	struct pci_controller *hose = pdn->phb;

	struct pnv_phb *phb = hose->private_data;

	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
@@ -373,6 +363,14 @@ static void *pnv_eeh_probe(struct pci_dn *pdn, void *data) 
	if (!edev || edev->pe)

		return NULL;



	/* already configured? */

	if (edev->pdev) {

		pr_debug("%s: found existing edev for %04x:%02x:%02x.%01x\n",

			__func__, hose->global_number, config_addr >> 8,

			PCI_SLOT(config_addr), PCI_FUNC(config_addr));

		return edev;

	}



	/* Skip for PCI-ISA bridge */

	if ((pdn->class_code >> 8) == PCI_CLASS_BRIDGE_ISA)

		return NULL;
@@ -464,7 +462,7 @@ static void *pnv_eeh_probe(struct pci_dn *pdn, void *data) 


	eeh_edev_dbg(edev, "EEH enabled on device\n");



	return NULL;

	return edev;

}



/**

arch/powerpc/platforms/pseries/eeh_pseries.c

+22 −1
Original line number Diff line number Diff line
@@ -77,7 +77,7 @@ void pseries_pcibios_bus_add_device(struct pci_dev *pdev) 
		eeh_add_to_parent_pe(edev);   /* Add as VF PE type */

	}

#endif

	eeh_add_device_late(pdev);

	eeh_probe_device(pdev);

}



/*
@@ -335,6 +335,26 @@ void pseries_eeh_init_edev(struct pci_dn *pdn) 
	eeh_save_bars(edev);

}



static struct eeh_dev *pseries_eeh_probe(struct pci_dev *pdev)

{

	struct eeh_dev *edev;

	struct pci_dn *pdn;



	pdn = pci_get_pdn_by_devfn(pdev->bus, pdev->devfn);

	if (!pdn)

		return NULL;



	/*

	 * If the system supports EEH on this device then the eeh_dev was

	 * configured and inserted into a PE in pseries_eeh_init_edev()

	 */

	edev = pdn_to_eeh_dev(pdn);

	if (!edev || !edev->pe)

		return NULL;



	return edev;

}



/**

 * pseries_eeh_init_edev_recursive - Enable EEH for the indicated device

 * @pdn: PCI device node
@@ -813,6 +833,7 @@ static int pseries_notify_resume(struct pci_dn *pdn) 
static struct eeh_ops pseries_eeh_ops = {

	.name			= "pseries",

	.init			= pseries_eeh_init,

	.probe			= pseries_eeh_probe,

	.set_option		= pseries_eeh_set_option,

	.get_pe_addr		= pseries_eeh_get_pe_addr,

	.get_state		= pseries_eeh_get_state,

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