linux_dsm_epyc7002/drivers/pci/pci.h
Hari Vyas 44bda4b7d2 PCI: Fix is_added/is_busmaster race condition
When a PCI device is detected, pdev->is_added is set to 1 and proc and
sysfs entries are created.

When the device is removed, pdev->is_added is checked for one and then
device is detached with clearing of proc and sys entries and at end,
pdev->is_added is set to 0.

is_added and is_busmaster are bit fields in pci_dev structure sharing same
memory location.

A strange issue was observed with multiple removal and rescan of a PCIe
NVMe device using sysfs commands where is_added flag was observed as zero
instead of one while removing device and proc,sys entries are not cleared.
This causes issue in later device addition with warning message
"proc_dir_entry" already registered.

Debugging revealed a race condition between the PCI core setting the
is_added bit in pci_bus_add_device() and the NVMe driver reset work-queue
setting the is_busmaster bit in pci_set_master().  As these fields are not
handled atomically, that clears the is_added bit.

Move the is_added bit to a separate private flag variable and use atomic
functions to set and retrieve the device addition state.  This avoids the
race because is_added no longer shares a memory location with is_busmaster.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200283
Signed-off-by: Hari Vyas <hari.vyas@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-31 11:27:54 -05:00

471 lines
15 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef DRIVERS_PCI_H
#define DRIVERS_PCI_H
#define PCI_FIND_CAP_TTL 48
#define PCI_VSEC_ID_INTEL_TBT 0x1234 /* Thunderbolt */
extern const unsigned char pcie_link_speed[];
bool pcie_cap_has_lnkctl(const struct pci_dev *dev);
/* Functions internal to the PCI core code */
int pci_create_sysfs_dev_files(struct pci_dev *pdev);
void pci_remove_sysfs_dev_files(struct pci_dev *pdev);
#if !defined(CONFIG_DMI) && !defined(CONFIG_ACPI)
static inline void pci_create_firmware_label_files(struct pci_dev *pdev)
{ return; }
static inline void pci_remove_firmware_label_files(struct pci_dev *pdev)
{ return; }
#else
void pci_create_firmware_label_files(struct pci_dev *pdev);
void pci_remove_firmware_label_files(struct pci_dev *pdev);
#endif
void pci_cleanup_rom(struct pci_dev *dev);
enum pci_mmap_api {
PCI_MMAP_SYSFS, /* mmap on /sys/bus/pci/devices/<BDF>/resource<N> */
PCI_MMAP_PROCFS /* mmap on /proc/bus/pci/<BDF> */
};
int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai,
enum pci_mmap_api mmap_api);
int pci_probe_reset_function(struct pci_dev *dev);
/**
* struct pci_platform_pm_ops - Firmware PM callbacks
*
* @is_manageable: returns 'true' if given device is power manageable by the
* platform firmware
*
* @set_state: invokes the platform firmware to set the device's power state
*
* @get_state: queries the platform firmware for a device's current power state
*
* @choose_state: returns PCI power state of given device preferred by the
* platform; to be used during system-wide transitions from a
* sleeping state to the working state and vice versa
*
* @set_wakeup: enables/disables wakeup capability for the device
*
* @need_resume: returns 'true' if the given device (which is currently
* suspended) needs to be resumed to be configured for system
* wakeup.
*
* If given platform is generally capable of power managing PCI devices, all of
* these callbacks are mandatory.
*/
struct pci_platform_pm_ops {
bool (*is_manageable)(struct pci_dev *dev);
int (*set_state)(struct pci_dev *dev, pci_power_t state);
pci_power_t (*get_state)(struct pci_dev *dev);
pci_power_t (*choose_state)(struct pci_dev *dev);
int (*set_wakeup)(struct pci_dev *dev, bool enable);
bool (*need_resume)(struct pci_dev *dev);
};
int pci_set_platform_pm(const struct pci_platform_pm_ops *ops);
void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
void pci_power_up(struct pci_dev *dev);
void pci_disable_enabled_device(struct pci_dev *dev);
int pci_finish_runtime_suspend(struct pci_dev *dev);
void pcie_clear_root_pme_status(struct pci_dev *dev);
int __pci_pme_wakeup(struct pci_dev *dev, void *ign);
void pci_pme_restore(struct pci_dev *dev);
bool pci_dev_keep_suspended(struct pci_dev *dev);
void pci_dev_complete_resume(struct pci_dev *pci_dev);
void pci_config_pm_runtime_get(struct pci_dev *dev);
void pci_config_pm_runtime_put(struct pci_dev *dev);
void pci_pm_init(struct pci_dev *dev);
void pci_ea_init(struct pci_dev *dev);
void pci_allocate_cap_save_buffers(struct pci_dev *dev);
void pci_free_cap_save_buffers(struct pci_dev *dev);
bool pci_bridge_d3_possible(struct pci_dev *dev);
void pci_bridge_d3_update(struct pci_dev *dev);
static inline void pci_wakeup_event(struct pci_dev *dev)
{
/* Wait 100 ms before the system can be put into a sleep state. */
pm_wakeup_event(&dev->dev, 100);
}
static inline bool pci_has_subordinate(struct pci_dev *pci_dev)
{
return !!(pci_dev->subordinate);
}
static inline bool pci_power_manageable(struct pci_dev *pci_dev)
{
/*
* Currently we allow normal PCI devices and PCI bridges transition
* into D3 if their bridge_d3 is set.
*/
return !pci_has_subordinate(pci_dev) || pci_dev->bridge_d3;
}
int pci_vpd_init(struct pci_dev *dev);
void pci_vpd_release(struct pci_dev *dev);
void pcie_vpd_create_sysfs_dev_files(struct pci_dev *dev);
void pcie_vpd_remove_sysfs_dev_files(struct pci_dev *dev);
/* PCI /proc functions */
#ifdef CONFIG_PROC_FS
int pci_proc_attach_device(struct pci_dev *dev);
int pci_proc_detach_device(struct pci_dev *dev);
int pci_proc_detach_bus(struct pci_bus *bus);
#else
static inline int pci_proc_attach_device(struct pci_dev *dev) { return 0; }
static inline int pci_proc_detach_device(struct pci_dev *dev) { return 0; }
static inline int pci_proc_detach_bus(struct pci_bus *bus) { return 0; }
#endif
/* Functions for PCI Hotplug drivers to use */
int pci_hp_add_bridge(struct pci_dev *dev);
#ifdef HAVE_PCI_LEGACY
void pci_create_legacy_files(struct pci_bus *bus);
void pci_remove_legacy_files(struct pci_bus *bus);
#else
static inline void pci_create_legacy_files(struct pci_bus *bus) { return; }
static inline void pci_remove_legacy_files(struct pci_bus *bus) { return; }
#endif
/* Lock for read/write access to pci device and bus lists */
extern struct rw_semaphore pci_bus_sem;
extern raw_spinlock_t pci_lock;
extern unsigned int pci_pm_d3_delay;
#ifdef CONFIG_PCI_MSI
void pci_no_msi(void);
#else
static inline void pci_no_msi(void) { }
#endif
static inline void pci_msi_set_enable(struct pci_dev *dev, int enable)
{
u16 control;
pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
control &= ~PCI_MSI_FLAGS_ENABLE;
if (enable)
control |= PCI_MSI_FLAGS_ENABLE;
pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
}
static inline void pci_msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
{
u16 ctrl;
pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
ctrl &= ~clear;
ctrl |= set;
pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
}
void pci_realloc_get_opt(char *);
static inline int pci_no_d1d2(struct pci_dev *dev)
{
unsigned int parent_dstates = 0;
if (dev->bus->self)
parent_dstates = dev->bus->self->no_d1d2;
return (dev->no_d1d2 || parent_dstates);
}
extern const struct attribute_group *pci_dev_groups[];
extern const struct attribute_group *pcibus_groups[];
extern const struct device_type pci_dev_type;
extern const struct attribute_group *pci_bus_groups[];
/**
* pci_match_one_device - Tell if a PCI device structure has a matching
* PCI device id structure
* @id: single PCI device id structure to match
* @dev: the PCI device structure to match against
*
* Returns the matching pci_device_id structure or %NULL if there is no match.
*/
static inline const struct pci_device_id *
pci_match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
{
if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
(id->device == PCI_ANY_ID || id->device == dev->device) &&
(id->subvendor == PCI_ANY_ID || id->subvendor == dev->subsystem_vendor) &&
(id->subdevice == PCI_ANY_ID || id->subdevice == dev->subsystem_device) &&
!((id->class ^ dev->class) & id->class_mask))
return id;
return NULL;
}
/* PCI slot sysfs helper code */
#define to_pci_slot(s) container_of(s, struct pci_slot, kobj)
extern struct kset *pci_slots_kset;
struct pci_slot_attribute {
struct attribute attr;
ssize_t (*show)(struct pci_slot *, char *);
ssize_t (*store)(struct pci_slot *, const char *, size_t);
};
#define to_pci_slot_attr(s) container_of(s, struct pci_slot_attribute, attr)
enum pci_bar_type {
pci_bar_unknown, /* Standard PCI BAR probe */
pci_bar_io, /* An I/O port BAR */
pci_bar_mem32, /* A 32-bit memory BAR */
pci_bar_mem64, /* A 64-bit memory BAR */
};
int pci_configure_extended_tags(struct pci_dev *dev, void *ign);
bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *pl,
int crs_timeout);
int pci_setup_device(struct pci_dev *dev);
int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
struct resource *res, unsigned int reg);
void pci_configure_ari(struct pci_dev *dev);
void __pci_bus_size_bridges(struct pci_bus *bus,
struct list_head *realloc_head);
void __pci_bus_assign_resources(const struct pci_bus *bus,
struct list_head *realloc_head,
struct list_head *fail_head);
bool pci_bus_clip_resource(struct pci_dev *dev, int idx);
void pci_reassigndev_resource_alignment(struct pci_dev *dev);
void pci_disable_bridge_window(struct pci_dev *dev);
/* PCIe link information */
#define PCIE_SPEED2STR(speed) \
((speed) == PCIE_SPEED_16_0GT ? "16 GT/s" : \
(speed) == PCIE_SPEED_8_0GT ? "8 GT/s" : \
(speed) == PCIE_SPEED_5_0GT ? "5 GT/s" : \
(speed) == PCIE_SPEED_2_5GT ? "2.5 GT/s" : \
"Unknown speed")
/* PCIe speed to Mb/s reduced by encoding overhead */
#define PCIE_SPEED2MBS_ENC(speed) \
((speed) == PCIE_SPEED_16_0GT ? 16000*128/130 : \
(speed) == PCIE_SPEED_8_0GT ? 8000*128/130 : \
(speed) == PCIE_SPEED_5_0GT ? 5000*8/10 : \
(speed) == PCIE_SPEED_2_5GT ? 2500*8/10 : \
0)
enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev);
enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev);
u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
enum pcie_link_width *width);
/* Single Root I/O Virtualization */
struct pci_sriov {
int pos; /* Capability position */
int nres; /* Number of resources */
u32 cap; /* SR-IOV Capabilities */
u16 ctrl; /* SR-IOV Control */
u16 total_VFs; /* Total VFs associated with the PF */
u16 initial_VFs; /* Initial VFs associated with the PF */
u16 num_VFs; /* Number of VFs available */
u16 offset; /* First VF Routing ID offset */
u16 stride; /* Following VF stride */
u16 vf_device; /* VF device ID */
u32 pgsz; /* Page size for BAR alignment */
u8 link; /* Function Dependency Link */
u8 max_VF_buses; /* Max buses consumed by VFs */
u16 driver_max_VFs; /* Max num VFs driver supports */
struct pci_dev *dev; /* Lowest numbered PF */
struct pci_dev *self; /* This PF */
u32 class; /* VF device */
u8 hdr_type; /* VF header type */
u16 subsystem_vendor; /* VF subsystem vendor */
u16 subsystem_device; /* VF subsystem device */
resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */
bool drivers_autoprobe; /* Auto probing of VFs by driver */
};
/* pci_dev priv_flags */
#define PCI_DEV_DISCONNECTED 0
#define PCI_DEV_ADDED 1
static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused)
{
set_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags);
return 0;
}
static inline bool pci_dev_is_disconnected(const struct pci_dev *dev)
{
return test_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags);
}
static inline void pci_dev_assign_added(struct pci_dev *dev, bool added)
{
assign_bit(PCI_DEV_ADDED, &dev->priv_flags, added);
}
static inline bool pci_dev_is_added(const struct pci_dev *dev)
{
return test_bit(PCI_DEV_ADDED, &dev->priv_flags);
}
#ifdef CONFIG_PCI_ATS
void pci_restore_ats_state(struct pci_dev *dev);
#else
static inline void pci_restore_ats_state(struct pci_dev *dev)
{
}
#endif /* CONFIG_PCI_ATS */
#ifdef CONFIG_PCI_IOV
int pci_iov_init(struct pci_dev *dev);
void pci_iov_release(struct pci_dev *dev);
void pci_iov_remove(struct pci_dev *dev);
void pci_iov_update_resource(struct pci_dev *dev, int resno);
resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno);
void pci_restore_iov_state(struct pci_dev *dev);
int pci_iov_bus_range(struct pci_bus *bus);
#else
static inline int pci_iov_init(struct pci_dev *dev)
{
return -ENODEV;
}
static inline void pci_iov_release(struct pci_dev *dev)
{
}
static inline void pci_iov_remove(struct pci_dev *dev)
{
}
static inline void pci_restore_iov_state(struct pci_dev *dev)
{
}
static inline int pci_iov_bus_range(struct pci_bus *bus)
{
return 0;
}
#endif /* CONFIG_PCI_IOV */
unsigned long pci_cardbus_resource_alignment(struct resource *);
static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
struct resource *res)
{
#ifdef CONFIG_PCI_IOV
int resno = res - dev->resource;
if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
return pci_sriov_resource_alignment(dev, resno);
#endif
if (dev->class >> 8 == PCI_CLASS_BRIDGE_CARDBUS)
return pci_cardbus_resource_alignment(res);
return resource_alignment(res);
}
void pci_enable_acs(struct pci_dev *dev);
/* PCI error reporting and recovery */
void pcie_do_fatal_recovery(struct pci_dev *dev, u32 service);
void pcie_do_nonfatal_recovery(struct pci_dev *dev);
bool pcie_wait_for_link(struct pci_dev *pdev, bool active);
#ifdef CONFIG_PCIEASPM
void pcie_aspm_init_link_state(struct pci_dev *pdev);
void pcie_aspm_exit_link_state(struct pci_dev *pdev);
void pcie_aspm_pm_state_change(struct pci_dev *pdev);
void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
#else
static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
#endif
#ifdef CONFIG_PCIEASPM_DEBUG
void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev);
void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev);
#else
static inline void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) { }
static inline void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) { }
#endif
#ifdef CONFIG_PCIE_PTM
void pci_ptm_init(struct pci_dev *dev);
#else
static inline void pci_ptm_init(struct pci_dev *dev) { }
#endif
struct pci_dev_reset_methods {
u16 vendor;
u16 device;
int (*reset)(struct pci_dev *dev, int probe);
};
#ifdef CONFIG_PCI_QUIRKS
int pci_dev_specific_reset(struct pci_dev *dev, int probe);
#else
static inline int pci_dev_specific_reset(struct pci_dev *dev, int probe)
{
return -ENOTTY;
}
#endif
#if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64)
int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
struct resource *res);
#endif
u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar);
int pci_rebar_get_current_size(struct pci_dev *pdev, int bar);
int pci_rebar_set_size(struct pci_dev *pdev, int bar, int size);
static inline u64 pci_rebar_size_to_bytes(int size)
{
return 1ULL << (size + 20);
}
struct device_node;
#ifdef CONFIG_OF
int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
int of_get_pci_domain_nr(struct device_node *node);
int of_pci_get_max_link_speed(struct device_node *node);
#else
static inline int
of_pci_parse_bus_range(struct device_node *node, struct resource *res)
{
return -EINVAL;
}
static inline int
of_get_pci_domain_nr(struct device_node *node)
{
return -1;
}
static inline int
of_pci_get_max_link_speed(struct device_node *node)
{
return -EINVAL;
}
#endif /* CONFIG_OF */
#if defined(CONFIG_OF_ADDRESS)
int devm_of_pci_get_host_bridge_resources(struct device *dev,
unsigned char busno, unsigned char bus_max,
struct list_head *resources, resource_size_t *io_base);
#else
static inline int devm_of_pci_get_host_bridge_resources(struct device *dev,
unsigned char busno, unsigned char bus_max,
struct list_head *resources, resource_size_t *io_base)
{
return -EINVAL;
}
#endif
#endif /* DRIVERS_PCI_H */