| Message ID | 20240924061437.2636766-4-Jiqian.Chen@amd.com |
|---|---|
| State | Accepted |
| Commit | 2fae6bb7be320270801b3c3b040189bd7daa8056 |
| Headers | show |
| Series | Support device passthrough when dom0 is PVH on Xen | expand |
On Tue, 24 Sep 2024, Jiqian Chen wrote: > On PVH dom0, when passthrough a device to domU, QEMU and xl tools > want to use gsi number to do pirq mapping, see QEMU code > xen_pt_realize->xc_physdev_map_pirq, and xl code > pci_add_dm_done->xc_physdev_map_pirq, but in current codes, the gsi > number is got from file /sys/bus/pci/devices/<sbdf>/irq, that is > wrong, because irq is not equal with gsi, they are in different > spaces, so pirq mapping fails. > And in current linux codes, there is no method to get gsi > for userspace. > > For above purpose, record gsi of pcistub devices when init > pcistub and add a new syscall into privcmd to let userspace > can get gsi when they have a need. > > Signed-off-by: Jiqian Chen <Jiqian.Chen@amd.com> > Signed-off-by: Huang Rui <ray.huang@amd.com> > Signed-off-by: Jiqian Chen <Jiqian.Chen@amd.com> This looks OK to me now. Assuming it passes the various possible builds with different configuration combinations: Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> > --- > v9->v10 changes: > Changed the macro wrapping "pcistub_get_gsi_from_sbdf" from "CONFIG_XEN_PCIDEV_BACKEND" to "CONFIG_XEN_ACPI". > Added "imply CONFIG_XEN_PCIDEV_BACKEND" for CONFIG_XEN_PRIVCMD Kconfig definition. > Added check "if (IS_REACHABLE(CONFIG_XEN_PCIDEV_BACKEND))" before calling pcistub_get_gsi_from_sbdf. > > v8->v9 changes: > Changed the syscall name from "IOCTL_PRIVCMD_GSI_FROM_DEV" to "IOCTL_PRIVCMD_PCIDEV_GET_GSI". Also changed the other functions name. > Changed the macro wrapping "pcistub_get_gsi_from_sbdf" from "CONFIG_XEN_ACPI" to "CONFIG_XEN_PCIDEV_BACKEND" to fix compile errors reported by CI robot. > Changed the parameter gsi of struct privcmd_pcidev_get_gsi from int to u32. > > v7->v8 changes: > In function privcmd_ioctl_gsi_from_dev, return -EINVAL when not confige CONFIG_XEN_ACPI. > Used PCI_BUS_NUM PCI_SLOT PCI_FUNC instead of open coding. > > v6->v7 changes: > Changed implementation to add a new parameter "gsi" to struct pcistub_device and set gsi when pcistub initialize device. Then when userspace wants to get gsi and pass sbdf, we can return that gsi. > > v5->v6 changes: > Changed implementation to add a new syscall to translate irq to gsi, instead adding a new gsi sysfs node, because the pci Maintainer didn't allow to add that sysfs node. > > v3->v5 changes: > No. > > v2->v3 changes: > Suggested by Roger: Abandoned previous implementations that added new syscall to get gsi from irq and changed to add a new sysfs node for gsi, then userspace can get gsi number from sysfs node. > --- > drivers/xen/Kconfig | 1 + > drivers/xen/privcmd.c | 32 +++++++++++++++++++++++++ > drivers/xen/xen-pciback/pci_stub.c | 38 +++++++++++++++++++++++++++--- > include/uapi/xen/privcmd.h | 7 ++++++ > include/xen/acpi.h | 9 +++++++ > 5 files changed, 84 insertions(+), 3 deletions(-) > > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig > index d5989871dd5d..fd83d51df2f4 100644 > --- a/drivers/xen/Kconfig > +++ b/drivers/xen/Kconfig > @@ -261,6 +261,7 @@ config XEN_SCSI_BACKEND > config XEN_PRIVCMD > tristate "Xen hypercall passthrough driver" > depends on XEN > + imply CONFIG_XEN_PCIDEV_BACKEND > default m > help > The hypercall passthrough driver allows privileged user programs to > diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c > index 9563650dfbaf..588f99a2b8df 100644 > --- a/drivers/xen/privcmd.c > +++ b/drivers/xen/privcmd.c > @@ -46,6 +46,9 @@ > #include <xen/page.h> > #include <xen/xen-ops.h> > #include <xen/balloon.h> > +#ifdef CONFIG_XEN_ACPI > +#include <xen/acpi.h> > +#endif > > #include "privcmd.h" > > @@ -844,6 +847,31 @@ static long privcmd_ioctl_mmap_resource(struct file *file, > return rc; > } > > +static long privcmd_ioctl_pcidev_get_gsi(struct file *file, void __user *udata) > +{ > +#if defined(CONFIG_XEN_ACPI) > + int rc = -EINVAL; > + struct privcmd_pcidev_get_gsi kdata; > + > + if (copy_from_user(&kdata, udata, sizeof(kdata))) > + return -EFAULT; > + > + if (IS_REACHABLE(CONFIG_XEN_PCIDEV_BACKEND)) > + rc = pcistub_get_gsi_from_sbdf(kdata.sbdf); > + > + if (rc < 0) > + return rc; > + > + kdata.gsi = rc; > + if (copy_to_user(udata, &kdata, sizeof(kdata))) > + return -EFAULT; > + > + return 0; > +#else > + return -EINVAL; > +#endif > +} > + > #ifdef CONFIG_XEN_PRIVCMD_EVENTFD > /* Irqfd support */ > static struct workqueue_struct *irqfd_cleanup_wq; > @@ -1543,6 +1571,10 @@ static long privcmd_ioctl(struct file *file, > ret = privcmd_ioctl_ioeventfd(file, udata); > break; > > + case IOCTL_PRIVCMD_PCIDEV_GET_GSI: > + ret = privcmd_ioctl_pcidev_get_gsi(file, udata); > + break; > + > default: > break; > } > diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c > index 8ce27333f54b..d003402ce66b 100644 > --- a/drivers/xen/xen-pciback/pci_stub.c > +++ b/drivers/xen/xen-pciback/pci_stub.c > @@ -56,6 +56,9 @@ struct pcistub_device { > > struct pci_dev *dev; > struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */ > +#ifdef CONFIG_XEN_ACPI > + int gsi; > +#endif > }; > > /* Access to pcistub_devices & seized_devices lists and the initialize_devices > @@ -88,6 +91,9 @@ static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev) > > kref_init(&psdev->kref); > spin_lock_init(&psdev->lock); > +#ifdef CONFIG_XEN_ACPI > + psdev->gsi = -1; > +#endif > > return psdev; > } > @@ -220,6 +226,25 @@ static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev, > return pci_dev; > } > > +#ifdef CONFIG_XEN_ACPI > +int pcistub_get_gsi_from_sbdf(unsigned int sbdf) > +{ > + struct pcistub_device *psdev; > + int domain = (sbdf >> 16) & 0xffff; > + int bus = PCI_BUS_NUM(sbdf); > + int slot = PCI_SLOT(sbdf); > + int func = PCI_FUNC(sbdf); > + > + psdev = pcistub_device_find(domain, bus, slot, func); > + > + if (!psdev) > + return -ENODEV; > + > + return psdev->gsi; > +} > +EXPORT_SYMBOL_GPL(pcistub_get_gsi_from_sbdf); > +#endif > + > struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev, > int domain, int bus, > int slot, int func) > @@ -367,14 +392,20 @@ static int pcistub_match(struct pci_dev *dev) > return found; > } > > -static int pcistub_init_device(struct pci_dev *dev) > +static int pcistub_init_device(struct pcistub_device *psdev) > { > struct xen_pcibk_dev_data *dev_data; > + struct pci_dev *dev; > #ifdef CONFIG_XEN_ACPI > int gsi, trigger, polarity; > #endif > int err = 0; > > + if (!psdev) > + return -EINVAL; > + > + dev = psdev->dev; > + > dev_dbg(&dev->dev, "initializing...\n"); > > /* The PCI backend is not intended to be a module (or to work with > @@ -452,6 +483,7 @@ static int pcistub_init_device(struct pci_dev *dev) > err = xen_pvh_setup_gsi(gsi, trigger, polarity); > if (err) > goto config_release; > + psdev->gsi = gsi; > } > #endif > > @@ -494,7 +526,7 @@ static int __init pcistub_init_devices_late(void) > > spin_unlock_irqrestore(&pcistub_devices_lock, flags); > > - err = pcistub_init_device(psdev->dev); > + err = pcistub_init_device(psdev); > if (err) { > dev_err(&psdev->dev->dev, > "error %d initializing device\n", err); > @@ -564,7 +596,7 @@ static int pcistub_seize(struct pci_dev *dev, > spin_unlock_irqrestore(&pcistub_devices_lock, flags); > > /* don't want irqs disabled when calling pcistub_init_device */ > - err = pcistub_init_device(psdev->dev); > + err = pcistub_init_device(psdev); > > spin_lock_irqsave(&pcistub_devices_lock, flags); > > diff --git a/include/uapi/xen/privcmd.h b/include/uapi/xen/privcmd.h > index 8b8c5d1420fe..8e2c8fd44764 100644 > --- a/include/uapi/xen/privcmd.h > +++ b/include/uapi/xen/privcmd.h > @@ -126,6 +126,11 @@ struct privcmd_ioeventfd { > __u8 pad[2]; > }; > > +struct privcmd_pcidev_get_gsi { > + __u32 sbdf; > + __u32 gsi; > +}; > + > /* > * @cmd: IOCTL_PRIVCMD_HYPERCALL > * @arg: &privcmd_hypercall_t > @@ -157,5 +162,7 @@ struct privcmd_ioeventfd { > _IOW('P', 8, struct privcmd_irqfd) > #define IOCTL_PRIVCMD_IOEVENTFD \ > _IOW('P', 9, struct privcmd_ioeventfd) > +#define IOCTL_PRIVCMD_PCIDEV_GET_GSI \ > + _IOC(_IOC_NONE, 'P', 10, sizeof(struct privcmd_pcidev_get_gsi)) > > #endif /* __LINUX_PUBLIC_PRIVCMD_H__ */ > diff --git a/include/xen/acpi.h b/include/xen/acpi.h > index 3bcfe82d9078..daa96a22d257 100644 > --- a/include/xen/acpi.h > +++ b/include/xen/acpi.h > @@ -91,4 +91,13 @@ static inline int xen_acpi_get_gsi_info(struct pci_dev *dev, > } > #endif > > +#ifdef CONFIG_XEN_PCI_STUB > +int pcistub_get_gsi_from_sbdf(unsigned int sbdf); > +#else > +static inline int pcistub_get_gsi_from_sbdf(unsigned int sbdf) > +{ > + return -1; > +} > +#endif > + > #endif /* _XEN_ACPI_H */ > -- > 2.34.1 >
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index d5989871dd5d..fd83d51df2f4 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -261,6 +261,7 @@ config XEN_SCSI_BACKEND config XEN_PRIVCMD tristate "Xen hypercall passthrough driver" depends on XEN + imply CONFIG_XEN_PCIDEV_BACKEND default m help The hypercall passthrough driver allows privileged user programs to diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 9563650dfbaf..588f99a2b8df 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -46,6 +46,9 @@ #include <xen/page.h> #include <xen/xen-ops.h> #include <xen/balloon.h> +#ifdef CONFIG_XEN_ACPI +#include <xen/acpi.h> +#endif #include "privcmd.h" @@ -844,6 +847,31 @@ static long privcmd_ioctl_mmap_resource(struct file *file, return rc; } +static long privcmd_ioctl_pcidev_get_gsi(struct file *file, void __user *udata) +{ +#if defined(CONFIG_XEN_ACPI) + int rc = -EINVAL; + struct privcmd_pcidev_get_gsi kdata; + + if (copy_from_user(&kdata, udata, sizeof(kdata))) + return -EFAULT; + + if (IS_REACHABLE(CONFIG_XEN_PCIDEV_BACKEND)) + rc = pcistub_get_gsi_from_sbdf(kdata.sbdf); + + if (rc < 0) + return rc; + + kdata.gsi = rc; + if (copy_to_user(udata, &kdata, sizeof(kdata))) + return -EFAULT; + + return 0; +#else + return -EINVAL; +#endif +} + #ifdef CONFIG_XEN_PRIVCMD_EVENTFD /* Irqfd support */ static struct workqueue_struct *irqfd_cleanup_wq; @@ -1543,6 +1571,10 @@ static long privcmd_ioctl(struct file *file, ret = privcmd_ioctl_ioeventfd(file, udata); break; + case IOCTL_PRIVCMD_PCIDEV_GET_GSI: + ret = privcmd_ioctl_pcidev_get_gsi(file, udata); + break; + default: break; } diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 8ce27333f54b..d003402ce66b 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -56,6 +56,9 @@ struct pcistub_device { struct pci_dev *dev; struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */ +#ifdef CONFIG_XEN_ACPI + int gsi; +#endif }; /* Access to pcistub_devices & seized_devices lists and the initialize_devices @@ -88,6 +91,9 @@ static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev) kref_init(&psdev->kref); spin_lock_init(&psdev->lock); +#ifdef CONFIG_XEN_ACPI + psdev->gsi = -1; +#endif return psdev; } @@ -220,6 +226,25 @@ static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev, return pci_dev; } +#ifdef CONFIG_XEN_ACPI +int pcistub_get_gsi_from_sbdf(unsigned int sbdf) +{ + struct pcistub_device *psdev; + int domain = (sbdf >> 16) & 0xffff; + int bus = PCI_BUS_NUM(sbdf); + int slot = PCI_SLOT(sbdf); + int func = PCI_FUNC(sbdf); + + psdev = pcistub_device_find(domain, bus, slot, func); + + if (!psdev) + return -ENODEV; + + return psdev->gsi; +} +EXPORT_SYMBOL_GPL(pcistub_get_gsi_from_sbdf); +#endif + struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev, int domain, int bus, int slot, int func) @@ -367,14 +392,20 @@ static int pcistub_match(struct pci_dev *dev) return found; } -static int pcistub_init_device(struct pci_dev *dev) +static int pcistub_init_device(struct pcistub_device *psdev) { struct xen_pcibk_dev_data *dev_data; + struct pci_dev *dev; #ifdef CONFIG_XEN_ACPI int gsi, trigger, polarity; #endif int err = 0; + if (!psdev) + return -EINVAL; + + dev = psdev->dev; + dev_dbg(&dev->dev, "initializing...\n"); /* The PCI backend is not intended to be a module (or to work with @@ -452,6 +483,7 @@ static int pcistub_init_device(struct pci_dev *dev) err = xen_pvh_setup_gsi(gsi, trigger, polarity); if (err) goto config_release; + psdev->gsi = gsi; } #endif @@ -494,7 +526,7 @@ static int __init pcistub_init_devices_late(void) spin_unlock_irqrestore(&pcistub_devices_lock, flags); - err = pcistub_init_device(psdev->dev); + err = pcistub_init_device(psdev); if (err) { dev_err(&psdev->dev->dev, "error %d initializing device\n", err); @@ -564,7 +596,7 @@ static int pcistub_seize(struct pci_dev *dev, spin_unlock_irqrestore(&pcistub_devices_lock, flags); /* don't want irqs disabled when calling pcistub_init_device */ - err = pcistub_init_device(psdev->dev); + err = pcistub_init_device(psdev); spin_lock_irqsave(&pcistub_devices_lock, flags); diff --git a/include/uapi/xen/privcmd.h b/include/uapi/xen/privcmd.h index 8b8c5d1420fe..8e2c8fd44764 100644 --- a/include/uapi/xen/privcmd.h +++ b/include/uapi/xen/privcmd.h @@ -126,6 +126,11 @@ struct privcmd_ioeventfd { __u8 pad[2]; }; +struct privcmd_pcidev_get_gsi { + __u32 sbdf; + __u32 gsi; +}; + /* * @cmd: IOCTL_PRIVCMD_HYPERCALL * @arg: &privcmd_hypercall_t @@ -157,5 +162,7 @@ struct privcmd_ioeventfd { _IOW('P', 8, struct privcmd_irqfd) #define IOCTL_PRIVCMD_IOEVENTFD \ _IOW('P', 9, struct privcmd_ioeventfd) +#define IOCTL_PRIVCMD_PCIDEV_GET_GSI \ + _IOC(_IOC_NONE, 'P', 10, sizeof(struct privcmd_pcidev_get_gsi)) #endif /* __LINUX_PUBLIC_PRIVCMD_H__ */ diff --git a/include/xen/acpi.h b/include/xen/acpi.h index 3bcfe82d9078..daa96a22d257 100644 --- a/include/xen/acpi.h +++ b/include/xen/acpi.h @@ -91,4 +91,13 @@ static inline int xen_acpi_get_gsi_info(struct pci_dev *dev, } #endif +#ifdef CONFIG_XEN_PCI_STUB +int pcistub_get_gsi_from_sbdf(unsigned int sbdf); +#else +static inline int pcistub_get_gsi_from_sbdf(unsigned int sbdf) +{ + return -1; +} +#endif + #endif /* _XEN_ACPI_H */