alistair23-linux/arch/s390/pci/pci_event.c
Sebastian Ott 9a99649f2a s390/pci: remove pdev pointer from arch data
For each PCI function we need to maintain arch specific data in
struct zpci_dev which also contains a pointer to struct pci_dev.

When a function is registered or deregistered (which is triggered by PCI
common code) we need to adjust that pointer which could interfere with
the machine check handler (triggered by FW) using zpci_dev->pdev.

Since multiple instances of the same pdev could exist at a time this can't
be solved with locking.

Fix that by ditching the pdev pointer and use a bus walk to reach
struct pci_dev (only one instance of a pdev can be registered at the bus
at a time).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-23 08:56:16 +01:00

157 lines
3.6 KiB
C

/*
* Copyright IBM Corp. 2012
*
* Author(s):
* Jan Glauber <jang@linux.vnet.ibm.com>
*/
#define KMSG_COMPONENT "zpci"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/pci.h>
#include <asm/pci_debug.h>
#include <asm/sclp.h>
/* Content Code Description for PCI Function Error */
struct zpci_ccdf_err {
u32 reserved1;
u32 fh; /* function handle */
u32 fid; /* function id */
u32 ett : 4; /* expected table type */
u32 mvn : 12; /* MSI vector number */
u32 dmaas : 8; /* DMA address space */
u32 : 6;
u32 q : 1; /* event qualifier */
u32 rw : 1; /* read/write */
u64 faddr; /* failing address */
u32 reserved3;
u16 reserved4;
u16 pec; /* PCI event code */
} __packed;
/* Content Code Description for PCI Function Availability */
struct zpci_ccdf_avail {
u32 reserved1;
u32 fh; /* function handle */
u32 fid; /* function id */
u32 reserved2;
u32 reserved3;
u32 reserved4;
u32 reserved5;
u16 reserved6;
u16 pec; /* PCI event code */
} __packed;
static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
{
struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
struct pci_dev *pdev = NULL;
zpci_err("error CCDF:\n");
zpci_err_hex(ccdf, sizeof(*ccdf));
if (zdev)
pdev = pci_get_slot(zdev->bus, ZPCI_DEVFN);
pr_err("%s: Event 0x%x reports an error for PCI function 0x%x\n",
pdev ? pci_name(pdev) : "n/a", ccdf->pec, ccdf->fid);
if (!pdev)
return;
pdev->error_state = pci_channel_io_perm_failure;
pci_dev_put(pdev);
}
void zpci_event_error(void *data)
{
if (zpci_is_enabled())
__zpci_event_error(data);
}
static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
{
struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
struct pci_dev *pdev = NULL;
int ret;
if (zdev)
pdev = pci_get_slot(zdev->bus, ZPCI_DEVFN);
pr_info("%s: Event 0x%x reconfigured PCI function 0x%x\n",
pdev ? pci_name(pdev) : "n/a", ccdf->pec, ccdf->fid);
zpci_err("avail CCDF:\n");
zpci_err_hex(ccdf, sizeof(*ccdf));
switch (ccdf->pec) {
case 0x0301: /* Reserved|Standby -> Configured */
if (!zdev) {
ret = clp_add_pci_device(ccdf->fid, ccdf->fh, 0);
if (ret)
break;
zdev = get_zdev_by_fid(ccdf->fid);
}
if (!zdev || zdev->state != ZPCI_FN_STATE_STANDBY)
break;
zdev->state = ZPCI_FN_STATE_CONFIGURED;
zdev->fh = ccdf->fh;
ret = zpci_enable_device(zdev);
if (ret)
break;
pci_lock_rescan_remove();
pci_rescan_bus(zdev->bus);
pci_unlock_rescan_remove();
break;
case 0x0302: /* Reserved -> Standby */
if (!zdev)
clp_add_pci_device(ccdf->fid, ccdf->fh, 0);
break;
case 0x0303: /* Deconfiguration requested */
if (pdev)
pci_stop_and_remove_bus_device_locked(pdev);
ret = zpci_disable_device(zdev);
if (ret)
break;
ret = sclp_pci_deconfigure(zdev->fid);
zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
if (!ret)
zdev->state = ZPCI_FN_STATE_STANDBY;
break;
case 0x0304: /* Configured -> Standby */
if (pdev) {
/* Give the driver a hint that the function is
* already unusable. */
pdev->error_state = pci_channel_io_perm_failure;
pci_stop_and_remove_bus_device_locked(pdev);
}
zdev->fh = ccdf->fh;
zpci_disable_device(zdev);
zdev->state = ZPCI_FN_STATE_STANDBY;
break;
case 0x0306: /* 0x308 or 0x302 for multiple devices */
clp_rescan_pci_devices();
break;
case 0x0308: /* Standby -> Reserved */
if (!zdev)
break;
pci_stop_root_bus(zdev->bus);
pci_remove_root_bus(zdev->bus);
break;
default:
break;
}
if (pdev)
pci_dev_put(pdev);
}
void zpci_event_availability(void *data)
{
if (zpci_is_enabled())
__zpci_event_availability(data);
}