alistair23-linux/drivers/vfio/pci/vfio_pci_private.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 Red Hat, Inc. All rights reserved.
* Author: Alex Williamson <alex.williamson@redhat.com>
*
* Derived from original vfio:
* Copyright 2010 Cisco Systems, Inc. All rights reserved.
* Author: Tom Lyon, pugs@cisco.com
*/
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/irqbypass.h>
#include <linux/types.h>
vfio/pci: Introduce VF token If we enable SR-IOV on a vfio-pci owned PF, the resulting VFs are not fully isolated from the PF. The PF can always cause a denial of service to the VF, even if by simply resetting itself. The degree to which a PF can access the data passed through a VF or interfere with its operation is dependent on a given SR-IOV implementation. Therefore we want to avoid a scenario where an existing vfio-pci based userspace driver might assume the PF driver is trusted, for example assigning a PF to one VM and VF to another with some expectation of isolation. IOMMU grouping could be a solution to this, but imposes an unnecessarily strong relationship between PF and VF drivers if they need to operate with the same IOMMU context. Instead we introduce a "VF token", which is essentially just a shared secret between PF and VF drivers, implemented as a UUID. The VF token can be set by a vfio-pci based PF driver and must be known by the vfio-pci based VF driver in order to gain access to the device. This allows the degree to which this VF token is considered secret to be determined by the applications and environment. For example a VM might generate a random UUID known only internally to the hypervisor while a userspace networking appliance might use a shared, or even well know, UUID among the application drivers. To incorporate this VF token, the VFIO_GROUP_GET_DEVICE_FD interface is extended to accept key=value pairs in addition to the device name. This allows us to most easily deny user access to the device without risk that existing userspace drivers assume region offsets, IRQs, and other device features, leading to more elaborate error paths. The format of these options are expected to take the form: "$DEVICE_NAME $OPTION1=$VALUE1 $OPTION2=$VALUE2" Where the device name is always provided first for compatibility and additional options are specified in a space separated list. The relation between and requirements for the additional options will be vfio bus driver dependent, however unknown or unused option within this schema should return error. This allow for future use of unknown options as well as a positive indication to the user that an option is used. An example VF token option would take this form: "0000:03:00.0 vf_token=2ab74924-c335-45f4-9b16-8569e5b08258" When accessing a VF where the PF is making use of vfio-pci, the user MUST provide the current vf_token. When accessing a PF, the user MUST provide the current vf_token IF there are active VF users or MAY provide a vf_token in order to set the current VF token when no VF users are active. The former requirement assures VF users that an unassociated driver cannot usurp the PF device. These semantics also imply that a VF token MUST be set by a PF driver before VF drivers can access their device, the default token is random and mechanisms to read the token are not provided in order to protect the VF token of previous users. Use of the vf_token option outside of these cases will return an error, as discussed above. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:28:27 -06:00
#include <linux/uuid.h>
#include <linux/notifier.h>
#ifndef VFIO_PCI_PRIVATE_H
#define VFIO_PCI_PRIVATE_H
#define VFIO_PCI_OFFSET_SHIFT 40
#define VFIO_PCI_OFFSET_TO_INDEX(off) (off >> VFIO_PCI_OFFSET_SHIFT)
#define VFIO_PCI_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_PCI_OFFSET_SHIFT)
#define VFIO_PCI_OFFSET_MASK (((u64)(1) << VFIO_PCI_OFFSET_SHIFT) - 1)
/* Special capability IDs predefined access */
#define PCI_CAP_ID_INVALID 0xFF /* default raw access */
#define PCI_CAP_ID_INVALID_VIRT 0xFE /* default virt access */
/* Cap maximum number of ioeventfds per device (arbitrary) */
#define VFIO_PCI_IOEVENTFD_MAX 1000
struct vfio_pci_ioeventfd {
struct list_head next;
struct virqfd *virqfd;
void __iomem *addr;
uint64_t data;
loff_t pos;
int bar;
int count;
};
struct vfio_pci_irq_ctx {
struct eventfd_ctx *trigger;
struct virqfd *unmask;
struct virqfd *mask;
char *name;
bool masked;
struct irq_bypass_producer producer;
};
struct vfio_pci_device;
struct vfio_pci_region;
struct vfio_pci_regops {
size_t (*rw)(struct vfio_pci_device *vdev, char __user *buf,
size_t count, loff_t *ppos, bool iswrite);
void (*release)(struct vfio_pci_device *vdev,
struct vfio_pci_region *region);
int (*mmap)(struct vfio_pci_device *vdev,
struct vfio_pci_region *region,
struct vm_area_struct *vma);
int (*add_capability)(struct vfio_pci_device *vdev,
struct vfio_pci_region *region,
struct vfio_info_cap *caps);
};
struct vfio_pci_region {
u32 type;
u32 subtype;
const struct vfio_pci_regops *ops;
void *data;
size_t size;
u32 flags;
};
struct vfio_pci_dummy_resource {
struct resource resource;
int index;
struct list_head res_next;
};
struct vfio_pci_reflck {
struct kref kref;
struct mutex lock;
};
vfio/pci: Introduce VF token If we enable SR-IOV on a vfio-pci owned PF, the resulting VFs are not fully isolated from the PF. The PF can always cause a denial of service to the VF, even if by simply resetting itself. The degree to which a PF can access the data passed through a VF or interfere with its operation is dependent on a given SR-IOV implementation. Therefore we want to avoid a scenario where an existing vfio-pci based userspace driver might assume the PF driver is trusted, for example assigning a PF to one VM and VF to another with some expectation of isolation. IOMMU grouping could be a solution to this, but imposes an unnecessarily strong relationship between PF and VF drivers if they need to operate with the same IOMMU context. Instead we introduce a "VF token", which is essentially just a shared secret between PF and VF drivers, implemented as a UUID. The VF token can be set by a vfio-pci based PF driver and must be known by the vfio-pci based VF driver in order to gain access to the device. This allows the degree to which this VF token is considered secret to be determined by the applications and environment. For example a VM might generate a random UUID known only internally to the hypervisor while a userspace networking appliance might use a shared, or even well know, UUID among the application drivers. To incorporate this VF token, the VFIO_GROUP_GET_DEVICE_FD interface is extended to accept key=value pairs in addition to the device name. This allows us to most easily deny user access to the device without risk that existing userspace drivers assume region offsets, IRQs, and other device features, leading to more elaborate error paths. The format of these options are expected to take the form: "$DEVICE_NAME $OPTION1=$VALUE1 $OPTION2=$VALUE2" Where the device name is always provided first for compatibility and additional options are specified in a space separated list. The relation between and requirements for the additional options will be vfio bus driver dependent, however unknown or unused option within this schema should return error. This allow for future use of unknown options as well as a positive indication to the user that an option is used. An example VF token option would take this form: "0000:03:00.0 vf_token=2ab74924-c335-45f4-9b16-8569e5b08258" When accessing a VF where the PF is making use of vfio-pci, the user MUST provide the current vf_token. When accessing a PF, the user MUST provide the current vf_token IF there are active VF users or MAY provide a vf_token in order to set the current VF token when no VF users are active. The former requirement assures VF users that an unassociated driver cannot usurp the PF device. These semantics also imply that a VF token MUST be set by a PF driver before VF drivers can access their device, the default token is random and mechanisms to read the token are not provided in order to protect the VF token of previous users. Use of the vf_token option outside of these cases will return an error, as discussed above. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:28:27 -06:00
struct vfio_pci_vf_token {
struct mutex lock;
uuid_t uuid;
int users;
};
struct vfio_pci_device {
struct pci_dev *pdev;
void __iomem *barmap[PCI_STD_NUM_BARS];
bool bar_mmap_supported[PCI_STD_NUM_BARS];
u8 *pci_config_map;
u8 *vconfig;
struct perm_bits *msi_perm;
spinlock_t irqlock;
struct mutex igate;
struct vfio_pci_irq_ctx *ctx;
int num_ctx;
int irq_type;
int num_regions;
struct vfio_pci_region *region;
u8 msi_qmax;
u8 msix_bar;
u16 msix_size;
u32 msix_offset;
u32 rbar[7];
bool pci_2_3;
bool virq_disabled;
bool reset_works;
bool extended_caps;
bool bardirty;
bool has_vga;
bool needs_reset;
vfio/pci: Hide broken INTx support from user INTx masking has two components, the first is that we need the ability to prevent the device from continuing to assert INTx. This is provided via the DisINTx bit in the command register and is the only thing we can really probe for when testing if INTx masking is supported. The second component is that the device needs to indicate if INTx is asserted via the interrupt status bit in the device status register. With these two features we can generically determine if one of the devices we own is asserting INTx, signal the user, and mask the interrupt while the user services the device. Generally if one or both of these components is broken we resort to APIC level interrupt masking, which requires an exclusive interrupt since we have no way to determine the source of the interrupt in a shared configuration. This often makes it difficult or impossible to configure the system for userspace use of the device, for an interrupt mode that the user may not need. One possible configuration of broken INTx masking is that the DisINTx support is fully functional, but the interrupt status bit never signals interrupt assertion. In this case we do have the ability to prevent the device from asserting INTx, but lack the ability to identify the interrupt source. For this case we can simply pretend that the device lacks INTx support entirely, keeping DisINTx set on the physical device, virtualizing this bit for the user, and virtualizing the interrupt pin register to indicate no INTx support. We already support virtualization of the DisINTx bit and already virtualize the interrupt pin for platforms without INTx support. By tying these components together, setting DisINTx on open and reset, and identifying devices broken in this particular way, we can provide support for them w/o the handicap of APIC level INTx masking. Intel i40e (XL710/X710) 10/20/40GbE NICs have been identified as being broken in this specific way. We leave the vfio-pci.nointxmask option as a mechanism to bypass this support, enabling INTx on the device with all the requirements of APIC level masking. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Cc: John Ronciak <john.ronciak@intel.com> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
2016-03-24 13:05:18 -06:00
bool nointx;
bool needs_pm_restore;
struct pci_saved_state *pci_saved_state;
struct pci_saved_state *pm_save;
struct vfio_pci_reflck *reflck;
int refcnt;
int ioeventfds_nr;
struct eventfd_ctx *err_trigger;
struct eventfd_ctx *req_trigger;
struct list_head dummy_resources_list;
struct mutex ioeventfds_lock;
struct list_head ioeventfds_list;
vfio/pci: Introduce VF token If we enable SR-IOV on a vfio-pci owned PF, the resulting VFs are not fully isolated from the PF. The PF can always cause a denial of service to the VF, even if by simply resetting itself. The degree to which a PF can access the data passed through a VF or interfere with its operation is dependent on a given SR-IOV implementation. Therefore we want to avoid a scenario where an existing vfio-pci based userspace driver might assume the PF driver is trusted, for example assigning a PF to one VM and VF to another with some expectation of isolation. IOMMU grouping could be a solution to this, but imposes an unnecessarily strong relationship between PF and VF drivers if they need to operate with the same IOMMU context. Instead we introduce a "VF token", which is essentially just a shared secret between PF and VF drivers, implemented as a UUID. The VF token can be set by a vfio-pci based PF driver and must be known by the vfio-pci based VF driver in order to gain access to the device. This allows the degree to which this VF token is considered secret to be determined by the applications and environment. For example a VM might generate a random UUID known only internally to the hypervisor while a userspace networking appliance might use a shared, or even well know, UUID among the application drivers. To incorporate this VF token, the VFIO_GROUP_GET_DEVICE_FD interface is extended to accept key=value pairs in addition to the device name. This allows us to most easily deny user access to the device without risk that existing userspace drivers assume region offsets, IRQs, and other device features, leading to more elaborate error paths. The format of these options are expected to take the form: "$DEVICE_NAME $OPTION1=$VALUE1 $OPTION2=$VALUE2" Where the device name is always provided first for compatibility and additional options are specified in a space separated list. The relation between and requirements for the additional options will be vfio bus driver dependent, however unknown or unused option within this schema should return error. This allow for future use of unknown options as well as a positive indication to the user that an option is used. An example VF token option would take this form: "0000:03:00.0 vf_token=2ab74924-c335-45f4-9b16-8569e5b08258" When accessing a VF where the PF is making use of vfio-pci, the user MUST provide the current vf_token. When accessing a PF, the user MUST provide the current vf_token IF there are active VF users or MAY provide a vf_token in order to set the current VF token when no VF users are active. The former requirement assures VF users that an unassociated driver cannot usurp the PF device. These semantics also imply that a VF token MUST be set by a PF driver before VF drivers can access their device, the default token is random and mechanisms to read the token are not provided in order to protect the VF token of previous users. Use of the vf_token option outside of these cases will return an error, as discussed above. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:28:27 -06:00
struct vfio_pci_vf_token *vf_token;
struct notifier_block nb;
};
#define is_intx(vdev) (vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX)
#define is_msi(vdev) (vdev->irq_type == VFIO_PCI_MSI_IRQ_INDEX)
#define is_msix(vdev) (vdev->irq_type == VFIO_PCI_MSIX_IRQ_INDEX)
#define is_irq_none(vdev) (!(is_intx(vdev) || is_msi(vdev) || is_msix(vdev)))
#define irq_is(vdev, type) (vdev->irq_type == type)
extern void vfio_pci_intx_mask(struct vfio_pci_device *vdev);
extern void vfio_pci_intx_unmask(struct vfio_pci_device *vdev);
extern int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev,
uint32_t flags, unsigned index,
unsigned start, unsigned count, void *data);
extern ssize_t vfio_pci_config_rw(struct vfio_pci_device *vdev,
char __user *buf, size_t count,
loff_t *ppos, bool iswrite);
extern ssize_t vfio_pci_bar_rw(struct vfio_pci_device *vdev, char __user *buf,
size_t count, loff_t *ppos, bool iswrite);
extern ssize_t vfio_pci_vga_rw(struct vfio_pci_device *vdev, char __user *buf,
size_t count, loff_t *ppos, bool iswrite);
extern long vfio_pci_ioeventfd(struct vfio_pci_device *vdev, loff_t offset,
uint64_t data, int count, int fd);
extern int vfio_pci_init_perm_bits(void);
extern void vfio_pci_uninit_perm_bits(void);
extern int vfio_config_init(struct vfio_pci_device *vdev);
extern void vfio_config_free(struct vfio_pci_device *vdev);
extern int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
unsigned int type, unsigned int subtype,
const struct vfio_pci_regops *ops,
size_t size, u32 flags, void *data);
extern int vfio_pci_set_power_state(struct vfio_pci_device *vdev,
pci_power_t state);
#ifdef CONFIG_VFIO_PCI_IGD
extern int vfio_pci_igd_init(struct vfio_pci_device *vdev);
#else
static inline int vfio_pci_igd_init(struct vfio_pci_device *vdev)
{
return -ENODEV;
}
#endif
vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver POWER9 Witherspoon machines come with 4 or 6 V100 GPUs which are not pluggable PCIe devices but still have PCIe links which are used for config space and MMIO. In addition to that the GPUs have 6 NVLinks which are connected to other GPUs and the POWER9 CPU. POWER9 chips have a special unit on a die called an NPU which is an NVLink2 host bus adapter with p2p connections to 2 to 3 GPUs, 3 or 2 NVLinks to each. These systems also support ATS (address translation services) which is a part of the NVLink2 protocol. Such GPUs also share on-board RAM (16GB or 32GB) to the system via the same NVLink2 so a CPU has cache-coherent access to a GPU RAM. This exports GPU RAM to the userspace as a new VFIO device region. This preregisters the new memory as device memory as it might be used for DMA. This inserts pfns from the fault handler as the GPU memory is not onlined until the vendor driver is loaded and trained the NVLinks so doing this earlier causes low level errors which we fence in the firmware so it does not hurt the host system but still better be avoided; for the same reason this does not map GPU RAM into the host kernel (usual thing for emulated access otherwise). This exports an ATSD (Address Translation Shootdown) register of NPU which allows TLB invalidations inside GPU for an operating system. The register conveniently occupies a single 64k page. It is also presented to the userspace as a new VFIO device region. One NPU has 8 ATSD registers, each of them can be used for TLB invalidation in a GPU linked to this NPU. This allocates one ATSD register per an NVLink bridge allowing passing up to 6 registers. Due to the host firmware bug (just recently fixed), only 1 ATSD register per NPU was actually advertised to the host system so this passes that alone register via the first NVLink bridge device in the group which is still enough as QEMU collects them all back and presents to the guest via vPHB to mimic the emulated NPU PHB on the host. In order to provide the userspace with the information about GPU-to-NVLink connections, this exports an additional capability called "tgt" (which is an abbreviated host system bus address). The "tgt" property tells the GPU its own system address and allows the guest driver to conglomerate the routing information so each GPU knows how to get directly to the other GPUs. For ATS to work, the nest MMU (an NVIDIA block in a P9 CPU) needs to know LPID (a logical partition ID or a KVM guest hardware ID in other words) and PID (a memory context ID of a userspace process, not to be confused with a linux pid). This assigns a GPU to LPID in the NPU and this is why this adds a listener for KVM on an IOMMU group. A PID comes via NVLink from a GPU and NPU uses a PID wildcard to pass it through. This requires coherent memory and ATSD to be available on the host as the GPU vendor only supports configurations with both features enabled and other configurations are known not to work. Because of this and because of the ways the features are advertised to the host system (which is a device tree with very platform specific properties), this requires enabled POWERNV platform. The V100 GPUs do not advertise any of these capabilities via the config space and there are more than just one device ID so this relies on the platform to tell whether these GPUs have special abilities such as NVLinks. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:10:36 -07:00
#ifdef CONFIG_VFIO_PCI_NVLINK2
extern int vfio_pci_nvdia_v100_nvlink2_init(struct vfio_pci_device *vdev);
extern int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev);
#else
static inline int vfio_pci_nvdia_v100_nvlink2_init(struct vfio_pci_device *vdev)
{
return -ENODEV;
}
static inline int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev)
{
return -ENODEV;
}
#endif
#endif /* VFIO_PCI_PRIVATE_H */