alistair23-linux/arch/x86/pci/common.c
Rafael J. Wysocki 9e8ce4b96b Revert "x86/PCI: Refine the way to release PCI IRQ resources"
Commit b4b55cda58 (Refine the way to release PCI IRQ resources)
introduced a regression in the PCI IRQ resource management by causing
the IRQ resource of a device, established when pci_enabled_device()
is called on a fully disabled device, to be released when the driver
is unbound from the device, regardless of the enable_cnt.

This leads to the situation that an ill-behaved driver can now make a
device unusable to subsequent drivers by an imbalance in their use of
pci_enable/disable_device().  That is a serious problem for secondary
drivers like vfio-pci, which are innocent of the transgressions of
the previous driver.

Since the solution of this problem is not immediate and requires
further discussion, revert commit b4b55cda58 and the issue it was
supposed to address (a bug related to xen-pciback) will be taken
care of in a different way going forward.

Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-20 14:56:19 +01:00

699 lines
16 KiB
C

/*
* Low-Level PCI Support for PC
*
* (c) 1999--2000 Martin Mares <mj@ucw.cz>
*/
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/slab.h>
#include <asm-generic/pci-bridge.h>
#include <asm/acpi.h>
#include <asm/segment.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/pci_x86.h>
#include <asm/setup.h>
unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
PCI_PROBE_MMCONF;
unsigned int pci_early_dump_regs;
static int pci_bf_sort;
static int smbios_type_b1_flag;
int pci_routeirq;
int noioapicquirk;
#ifdef CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS
int noioapicreroute = 0;
#else
int noioapicreroute = 1;
#endif
int pcibios_last_bus = -1;
unsigned long pirq_table_addr;
const struct pci_raw_ops *__read_mostly raw_pci_ops;
const struct pci_raw_ops *__read_mostly raw_pci_ext_ops;
int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
int reg, int len, u32 *val)
{
if (domain == 0 && reg < 256 && raw_pci_ops)
return raw_pci_ops->read(domain, bus, devfn, reg, len, val);
if (raw_pci_ext_ops)
return raw_pci_ext_ops->read(domain, bus, devfn, reg, len, val);
return -EINVAL;
}
int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
int reg, int len, u32 val)
{
if (domain == 0 && reg < 256 && raw_pci_ops)
return raw_pci_ops->write(domain, bus, devfn, reg, len, val);
if (raw_pci_ext_ops)
return raw_pci_ext_ops->write(domain, bus, devfn, reg, len, val);
return -EINVAL;
}
static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
{
return raw_pci_read(pci_domain_nr(bus), bus->number,
devfn, where, size, value);
}
static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
{
return raw_pci_write(pci_domain_nr(bus), bus->number,
devfn, where, size, value);
}
struct pci_ops pci_root_ops = {
.read = pci_read,
.write = pci_write,
};
/*
* This interrupt-safe spinlock protects all accesses to PCI
* configuration space.
*/
DEFINE_RAW_SPINLOCK(pci_config_lock);
static int __init can_skip_ioresource_align(const struct dmi_system_id *d)
{
pci_probe |= PCI_CAN_SKIP_ISA_ALIGN;
printk(KERN_INFO "PCI: %s detected, can skip ISA alignment\n", d->ident);
return 0;
}
static const struct dmi_system_id can_skip_pciprobe_dmi_table[] __initconst = {
/*
* Systems where PCI IO resource ISA alignment can be skipped
* when the ISA enable bit in the bridge control is not set
*/
{
.callback = can_skip_ioresource_align,
.ident = "IBM System x3800",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
},
},
{
.callback = can_skip_ioresource_align,
.ident = "IBM System x3850",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
DMI_MATCH(DMI_PRODUCT_NAME, "x3850"),
},
},
{
.callback = can_skip_ioresource_align,
.ident = "IBM System x3950",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
DMI_MATCH(DMI_PRODUCT_NAME, "x3950"),
},
},
{}
};
void __init dmi_check_skip_isa_align(void)
{
dmi_check_system(can_skip_pciprobe_dmi_table);
}
static void pcibios_fixup_device_resources(struct pci_dev *dev)
{
struct resource *rom_r = &dev->resource[PCI_ROM_RESOURCE];
struct resource *bar_r;
int bar;
if (pci_probe & PCI_NOASSIGN_BARS) {
/*
* If the BIOS did not assign the BAR, zero out the
* resource so the kernel doesn't attmept to assign
* it later on in pci_assign_unassigned_resources
*/
for (bar = 0; bar <= PCI_STD_RESOURCE_END; bar++) {
bar_r = &dev->resource[bar];
if (bar_r->start == 0 && bar_r->end != 0) {
bar_r->flags = 0;
bar_r->end = 0;
}
}
}
if (pci_probe & PCI_NOASSIGN_ROMS) {
if (rom_r->parent)
return;
if (rom_r->start) {
/* we deal with BIOS assigned ROM later */
return;
}
rom_r->start = rom_r->end = rom_r->flags = 0;
}
}
/*
* Called after each bus is probed, but before its children
* are examined.
*/
void pcibios_fixup_bus(struct pci_bus *b)
{
struct pci_dev *dev;
pci_read_bridge_bases(b);
list_for_each_entry(dev, &b->devices, bus_list)
pcibios_fixup_device_resources(dev);
}
void pcibios_add_bus(struct pci_bus *bus)
{
acpi_pci_add_bus(bus);
}
void pcibios_remove_bus(struct pci_bus *bus)
{
acpi_pci_remove_bus(bus);
}
/*
* Only use DMI information to set this if nothing was passed
* on the kernel command line (which was parsed earlier).
*/
static int __init set_bf_sort(const struct dmi_system_id *d)
{
if (pci_bf_sort == pci_bf_sort_default) {
pci_bf_sort = pci_dmi_bf;
printk(KERN_INFO "PCI: %s detected, enabling pci=bfsort.\n", d->ident);
}
return 0;
}
static void __init read_dmi_type_b1(const struct dmi_header *dm,
void *private_data)
{
u8 *d = (u8 *)dm + 4;
if (dm->type != 0xB1)
return;
switch (((*(u32 *)d) >> 9) & 0x03) {
case 0x00:
printk(KERN_INFO "dmi type 0xB1 record - unknown flag\n");
break;
case 0x01: /* set pci=bfsort */
smbios_type_b1_flag = 1;
break;
case 0x02: /* do not set pci=bfsort */
smbios_type_b1_flag = 2;
break;
default:
break;
}
}
static int __init find_sort_method(const struct dmi_system_id *d)
{
dmi_walk(read_dmi_type_b1, NULL);
if (smbios_type_b1_flag == 1) {
set_bf_sort(d);
return 0;
}
return -1;
}
/*
* Enable renumbering of PCI bus# ranges to reach all PCI busses (Cardbus)
*/
#ifdef __i386__
static int __init assign_all_busses(const struct dmi_system_id *d)
{
pci_probe |= PCI_ASSIGN_ALL_BUSSES;
printk(KERN_INFO "%s detected: enabling PCI bus# renumbering"
" (pci=assign-busses)\n", d->ident);
return 0;
}
#endif
static int __init set_scan_all(const struct dmi_system_id *d)
{
printk(KERN_INFO "PCI: %s detected, enabling pci=pcie_scan_all\n",
d->ident);
pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
return 0;
}
static const struct dmi_system_id pciprobe_dmi_table[] __initconst = {
#ifdef __i386__
/*
* Laptops which need pci=assign-busses to see Cardbus cards
*/
{
.callback = assign_all_busses,
.ident = "Samsung X20 Laptop",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Samsung Electronics"),
DMI_MATCH(DMI_PRODUCT_NAME, "SX20S"),
},
},
#endif /* __i386__ */
{
.callback = set_bf_sort,
.ident = "Dell PowerEdge 1950",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1950"),
},
},
{
.callback = set_bf_sort,
.ident = "Dell PowerEdge 1955",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1955"),
},
},
{
.callback = set_bf_sort,
.ident = "Dell PowerEdge 2900",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2900"),
},
},
{
.callback = set_bf_sort,
.ident = "Dell PowerEdge 2950",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2950"),
},
},
{
.callback = set_bf_sort,
.ident = "Dell PowerEdge R900",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge R900"),
},
},
{
.callback = find_sort_method,
.ident = "Dell System",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL20p G3",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL20p G3"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL20p G4",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL20p G4"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL30p G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL30p G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL25p G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL25p G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL35p G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL35p G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL45p G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL45p G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL45p G2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL45p G2"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL460c G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL460c G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL465c G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL465c G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL480c G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL480c G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant BL685c G1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant BL685c G1"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant DL360",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant DL360"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant DL380",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant DL380"),
},
},
#ifdef __i386__
{
.callback = assign_all_busses,
.ident = "Compaq EVO N800c",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
DMI_MATCH(DMI_PRODUCT_NAME, "EVO N800c"),
},
},
#endif
{
.callback = set_bf_sort,
.ident = "HP ProLiant DL385 G2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant DL385 G2"),
},
},
{
.callback = set_bf_sort,
.ident = "HP ProLiant DL585 G2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HP"),
DMI_MATCH(DMI_PRODUCT_NAME, "ProLiant DL585 G2"),
},
},
{
.callback = set_scan_all,
.ident = "Stratus/NEC ftServer",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Stratus"),
DMI_MATCH(DMI_PRODUCT_NAME, "ftServer"),
},
},
{
.callback = set_scan_all,
.ident = "Stratus/NEC ftServer",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
DMI_MATCH(DMI_PRODUCT_NAME, "Express5800/R32"),
},
},
{
.callback = set_scan_all,
.ident = "Stratus/NEC ftServer",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
DMI_MATCH(DMI_PRODUCT_NAME, "Express5800/R31"),
},
},
{}
};
void __init dmi_check_pciprobe(void)
{
dmi_check_system(pciprobe_dmi_table);
}
void pcibios_scan_root(int busnum)
{
struct pci_bus *bus;
struct pci_sysdata *sd;
LIST_HEAD(resources);
sd = kzalloc(sizeof(*sd), GFP_KERNEL);
if (!sd) {
printk(KERN_ERR "PCI: OOM, skipping PCI bus %02x\n", busnum);
return;
}
sd->node = x86_pci_root_bus_node(busnum);
x86_pci_root_bus_resources(busnum, &resources);
printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, sd, &resources);
if (!bus) {
pci_free_resource_list(&resources);
kfree(sd);
}
}
void __init pcibios_set_cache_line_size(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
/*
* Set PCI cacheline size to that of the CPU if the CPU has reported it.
* (For older CPUs that don't support cpuid, we se it to 32 bytes
* It's also good for 386/486s (which actually have 16)
* as quite a few PCI devices do not support smaller values.
*/
if (c->x86_clflush_size > 0) {
pci_dfl_cache_line_size = c->x86_clflush_size >> 2;
printk(KERN_DEBUG "PCI: pci_cache_line_size set to %d bytes\n",
pci_dfl_cache_line_size << 2);
} else {
pci_dfl_cache_line_size = 32 >> 2;
printk(KERN_DEBUG "PCI: Unknown cacheline size. Setting to 32 bytes\n");
}
}
int __init pcibios_init(void)
{
if (!raw_pci_ops) {
printk(KERN_WARNING "PCI: System does not support PCI\n");
return 0;
}
pcibios_set_cache_line_size();
pcibios_resource_survey();
if (pci_bf_sort >= pci_force_bf)
pci_sort_breadthfirst();
return 0;
}
char *__init pcibios_setup(char *str)
{
if (!strcmp(str, "off")) {
pci_probe = 0;
return NULL;
} else if (!strcmp(str, "bfsort")) {
pci_bf_sort = pci_force_bf;
return NULL;
} else if (!strcmp(str, "nobfsort")) {
pci_bf_sort = pci_force_nobf;
return NULL;
}
#ifdef CONFIG_PCI_BIOS
else if (!strcmp(str, "bios")) {
pci_probe = PCI_PROBE_BIOS;
return NULL;
} else if (!strcmp(str, "nobios")) {
pci_probe &= ~PCI_PROBE_BIOS;
return NULL;
} else if (!strcmp(str, "biosirq")) {
pci_probe |= PCI_BIOS_IRQ_SCAN;
return NULL;
} else if (!strncmp(str, "pirqaddr=", 9)) {
pirq_table_addr = simple_strtoul(str+9, NULL, 0);
return NULL;
}
#endif
#ifdef CONFIG_PCI_DIRECT
else if (!strcmp(str, "conf1")) {
pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
return NULL;
}
else if (!strcmp(str, "conf2")) {
pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
return NULL;
}
#endif
#ifdef CONFIG_PCI_MMCONFIG
else if (!strcmp(str, "nommconf")) {
pci_probe &= ~PCI_PROBE_MMCONF;
return NULL;
}
else if (!strcmp(str, "check_enable_amd_mmconf")) {
pci_probe |= PCI_CHECK_ENABLE_AMD_MMCONF;
return NULL;
}
#endif
else if (!strcmp(str, "noacpi")) {
acpi_noirq_set();
return NULL;
}
else if (!strcmp(str, "noearly")) {
pci_probe |= PCI_PROBE_NOEARLY;
return NULL;
}
else if (!strcmp(str, "usepirqmask")) {
pci_probe |= PCI_USE_PIRQ_MASK;
return NULL;
} else if (!strncmp(str, "irqmask=", 8)) {
pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
return NULL;
} else if (!strncmp(str, "lastbus=", 8)) {
pcibios_last_bus = simple_strtol(str+8, NULL, 0);
return NULL;
} else if (!strcmp(str, "rom")) {
pci_probe |= PCI_ASSIGN_ROMS;
return NULL;
} else if (!strcmp(str, "norom")) {
pci_probe |= PCI_NOASSIGN_ROMS;
return NULL;
} else if (!strcmp(str, "nobar")) {
pci_probe |= PCI_NOASSIGN_BARS;
return NULL;
} else if (!strcmp(str, "assign-busses")) {
pci_probe |= PCI_ASSIGN_ALL_BUSSES;
return NULL;
} else if (!strcmp(str, "use_crs")) {
pci_probe |= PCI_USE__CRS;
return NULL;
} else if (!strcmp(str, "nocrs")) {
pci_probe |= PCI_ROOT_NO_CRS;
return NULL;
} else if (!strcmp(str, "earlydump")) {
pci_early_dump_regs = 1;
return NULL;
} else if (!strcmp(str, "routeirq")) {
pci_routeirq = 1;
return NULL;
} else if (!strcmp(str, "skip_isa_align")) {
pci_probe |= PCI_CAN_SKIP_ISA_ALIGN;
return NULL;
} else if (!strcmp(str, "noioapicquirk")) {
noioapicquirk = 1;
return NULL;
} else if (!strcmp(str, "ioapicreroute")) {
if (noioapicreroute != -1)
noioapicreroute = 0;
return NULL;
} else if (!strcmp(str, "noioapicreroute")) {
if (noioapicreroute != -1)
noioapicreroute = 1;
return NULL;
}
return str;
}
unsigned int pcibios_assign_all_busses(void)
{
return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
}
int pcibios_add_device(struct pci_dev *dev)
{
struct setup_data *data;
struct pci_setup_rom *rom;
u64 pa_data;
pa_data = boot_params.hdr.setup_data;
while (pa_data) {
data = ioremap(pa_data, sizeof(*rom));
if (!data)
return -ENOMEM;
if (data->type == SETUP_PCI) {
rom = (struct pci_setup_rom *)data;
if ((pci_domain_nr(dev->bus) == rom->segment) &&
(dev->bus->number == rom->bus) &&
(PCI_SLOT(dev->devfn) == rom->device) &&
(PCI_FUNC(dev->devfn) == rom->function) &&
(dev->vendor == rom->vendor) &&
(dev->device == rom->devid)) {
dev->rom = pa_data +
offsetof(struct pci_setup_rom, romdata);
dev->romlen = rom->pcilen;
}
}
pa_data = data->next;
iounmap(data);
}
return 0;
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
int err;
if ((err = pci_enable_resources(dev, mask)) < 0)
return err;
if (!pci_dev_msi_enabled(dev))
return pcibios_enable_irq(dev);
return 0;
}
void pcibios_disable_device (struct pci_dev *dev)
{
if (!pci_dev_msi_enabled(dev) && pcibios_disable_irq)
pcibios_disable_irq(dev);
}
int pci_ext_cfg_avail(void)
{
if (raw_pci_ext_ops)
return 1;
else
return 0;
}