diff --git a/Documentation/vfio.txt b/Documentation/vfio.txt index b9ca02370d46..96978eced341 100644 --- a/Documentation/vfio.txt +++ b/Documentation/vfio.txt @@ -305,7 +305,15 @@ faster, the map/unmap handling has been implemented in real mode which provides an excellent performance which has limitations such as inability to do locked pages accounting in real time. -So 3 additional ioctls have been added: +4) According to sPAPR specification, A Partitionable Endpoint (PE) is an I/O +subtree that can be treated as a unit for the purposes of partitioning and +error recovery. A PE may be a single or multi-function IOA (IO Adapter), a +function of a multi-function IOA, or multiple IOAs (possibly including switch +and bridge structures above the multiple IOAs). PPC64 guests detect PCI errors +and recover from them via EEH RTAS services, which works on the basis of +additional ioctl commands. + +So 4 additional ioctls have been added: VFIO_IOMMU_SPAPR_TCE_GET_INFO - returns the size and the start of the DMA window on the PCI bus. @@ -316,9 +324,12 @@ So 3 additional ioctls have been added: VFIO_IOMMU_DISABLE - disables the container. + VFIO_EEH_PE_OP - provides an API for EEH setup, error detection and recovery. The code flow from the example above should be slightly changed: + struct vfio_eeh_pe_op pe_op = { .argsz = sizeof(pe_op), .flags = 0 }; + ..... /* Add the group to the container */ ioctl(group, VFIO_GROUP_SET_CONTAINER, &container); @@ -342,9 +353,79 @@ The code flow from the example above should be slightly changed: dma_map.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE; /* Check here is .iova/.size are within DMA window from spapr_iommu_info */ - ioctl(container, VFIO_IOMMU_MAP_DMA, &dma_map); - ..... + + /* Get a file descriptor for the device */ + device = ioctl(group, VFIO_GROUP_GET_DEVICE_FD, "0000:06:0d.0"); + + .... + + /* Gratuitous device reset and go... */ + ioctl(device, VFIO_DEVICE_RESET); + + /* Make sure EEH is supported */ + ioctl(container, VFIO_CHECK_EXTENSION, VFIO_EEH); + + /* Enable the EEH functionality on the device */ + pe_op.op = VFIO_EEH_PE_ENABLE; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* You're suggested to create additional data struct to represent + * PE, and put child devices belonging to same IOMMU group to the + * PE instance for later reference. + */ + + /* Check the PE's state and make sure it's in functional state */ + pe_op.op = VFIO_EEH_PE_GET_STATE; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* Save device state using pci_save_state(). + * EEH should be enabled on the specified device. + */ + + .... + + /* When 0xFF's returned from reading PCI config space or IO BARs + * of the PCI device. Check the PE's state to see if that has been + * frozen. + */ + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* Waiting for pending PCI transactions to be completed and don't + * produce any more PCI traffic from/to the affected PE until + * recovery is finished. + */ + + /* Enable IO for the affected PE and collect logs. Usually, the + * standard part of PCI config space, AER registers are dumped + * as logs for further analysis. + */ + pe_op.op = VFIO_EEH_PE_UNFREEZE_IO; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* + * Issue PE reset: hot or fundamental reset. Usually, hot reset + * is enough. However, the firmware of some PCI adapters would + * require fundamental reset. + */ + pe_op.op = VFIO_EEH_PE_RESET_HOT; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + pe_op.op = VFIO_EEH_PE_RESET_DEACTIVATE; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* Configure the PCI bridges for the affected PE */ + pe_op.op = VFIO_EEH_PE_CONFIGURE; + ioctl(container, VFIO_EEH_PE_OP, &pe_op); + + /* Restored state we saved at initialization time. pci_restore_state() + * is good enough as an example. + */ + + /* Hopefully, error is recovered successfully. Now, you can resume to + * start PCI traffic to/from the affected PE. + */ + + .... ------------------------------------------------------------------------------- diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile index 72bfabc8629e..50e30bc75e85 100644 --- a/drivers/vfio/Makefile +++ b/drivers/vfio/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_VFIO) += vfio.o obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o +obj-$(CONFIG_EEH) += vfio_spapr_eeh.o obj-$(CONFIG_VFIO_PCI) += pci/ diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 010e0f8b8e4f..e2ee80f36e3e 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -157,8 +157,10 @@ static void vfio_pci_release(void *device_data) { struct vfio_pci_device *vdev = device_data; - if (atomic_dec_and_test(&vdev->refcnt)) + if (atomic_dec_and_test(&vdev->refcnt)) { + vfio_spapr_pci_eeh_release(vdev->pdev); vfio_pci_disable(vdev); + } module_put(THIS_MODULE); } @@ -166,19 +168,27 @@ static void vfio_pci_release(void *device_data) static int vfio_pci_open(void *device_data) { struct vfio_pci_device *vdev = device_data; + int ret; if (!try_module_get(THIS_MODULE)) return -ENODEV; if (atomic_inc_return(&vdev->refcnt) == 1) { - int ret = vfio_pci_enable(vdev); + ret = vfio_pci_enable(vdev); + if (ret) + goto error; + + ret = vfio_spapr_pci_eeh_open(vdev->pdev); if (ret) { - module_put(THIS_MODULE); - return ret; + vfio_pci_disable(vdev); + goto error; } } return 0; +error: + module_put(THIS_MODULE); + return ret; } static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index a84788ba662c..730b4ef3e0cc 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -156,7 +156,16 @@ static long tce_iommu_ioctl(void *iommu_data, switch (cmd) { case VFIO_CHECK_EXTENSION: - return (arg == VFIO_SPAPR_TCE_IOMMU) ? 1 : 0; + switch (arg) { + case VFIO_SPAPR_TCE_IOMMU: + ret = 1; + break; + default: + ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg); + break; + } + + return (ret < 0) ? 0 : ret; case VFIO_IOMMU_SPAPR_TCE_GET_INFO: { struct vfio_iommu_spapr_tce_info info; @@ -283,6 +292,12 @@ static long tce_iommu_ioctl(void *iommu_data, tce_iommu_disable(container); mutex_unlock(&container->lock); return 0; + case VFIO_EEH_PE_OP: + if (!container->tbl || !container->tbl->it_group) + return -ENODEV; + + return vfio_spapr_iommu_eeh_ioctl(container->tbl->it_group, + cmd, arg); } return -ENOTTY; diff --git a/drivers/vfio/vfio_spapr_eeh.c b/drivers/vfio/vfio_spapr_eeh.c new file mode 100644 index 000000000000..f834b4ce1431 --- /dev/null +++ b/drivers/vfio/vfio_spapr_eeh.c @@ -0,0 +1,87 @@ +/* + * EEH functionality support for VFIO devices. The feature is only + * available on sPAPR compatible platforms. + * + * Copyright Gavin Shan, IBM Corporation 2014. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include + +/* We might build address mapping here for "fast" path later */ +int vfio_spapr_pci_eeh_open(struct pci_dev *pdev) +{ + return eeh_dev_open(pdev); +} + +void vfio_spapr_pci_eeh_release(struct pci_dev *pdev) +{ + eeh_dev_release(pdev); +} + +long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group, + unsigned int cmd, unsigned long arg) +{ + struct eeh_pe *pe; + struct vfio_eeh_pe_op op; + unsigned long minsz; + long ret = -EINVAL; + + switch (cmd) { + case VFIO_CHECK_EXTENSION: + if (arg == VFIO_EEH) + ret = eeh_enabled() ? 1 : 0; + else + ret = 0; + break; + case VFIO_EEH_PE_OP: + pe = eeh_iommu_group_to_pe(group); + if (!pe) + return -ENODEV; + + minsz = offsetofend(struct vfio_eeh_pe_op, op); + if (copy_from_user(&op, (void __user *)arg, minsz)) + return -EFAULT; + if (op.argsz < minsz || op.flags) + return -EINVAL; + + switch (op.op) { + case VFIO_EEH_PE_DISABLE: + ret = eeh_pe_set_option(pe, EEH_OPT_DISABLE); + break; + case VFIO_EEH_PE_ENABLE: + ret = eeh_pe_set_option(pe, EEH_OPT_ENABLE); + break; + case VFIO_EEH_PE_UNFREEZE_IO: + ret = eeh_pe_set_option(pe, EEH_OPT_THAW_MMIO); + break; + case VFIO_EEH_PE_UNFREEZE_DMA: + ret = eeh_pe_set_option(pe, EEH_OPT_THAW_DMA); + break; + case VFIO_EEH_PE_GET_STATE: + ret = eeh_pe_get_state(pe); + break; + case VFIO_EEH_PE_RESET_DEACTIVATE: + ret = eeh_pe_reset(pe, EEH_RESET_DEACTIVATE); + break; + case VFIO_EEH_PE_RESET_HOT: + ret = eeh_pe_reset(pe, EEH_RESET_HOT); + break; + case VFIO_EEH_PE_RESET_FUNDAMENTAL: + ret = eeh_pe_reset(pe, EEH_RESET_FUNDAMENTAL); + break; + case VFIO_EEH_PE_CONFIGURE: + ret = eeh_pe_configure(pe); + break; + default: + ret = -EINVAL; + } + } + + return ret; +} diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 8ec980b5e3af..25a0fbd4b998 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -98,4 +98,27 @@ extern int vfio_external_user_iommu_id(struct vfio_group *group); extern long vfio_external_check_extension(struct vfio_group *group, unsigned long arg); +#ifdef CONFIG_EEH +extern int vfio_spapr_pci_eeh_open(struct pci_dev *pdev); +extern void vfio_spapr_pci_eeh_release(struct pci_dev *pdev); +extern long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group, + unsigned int cmd, + unsigned long arg); +#else +static inline int vfio_spapr_pci_eeh_open(struct pci_dev *pdev) +{ + return 0; +} + +static inline void vfio_spapr_pci_eeh_release(struct pci_dev *pdev) +{ +} + +static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group, + unsigned int cmd, + unsigned long arg) +{ + return -ENOTTY; +} +#endif /* CONFIG_EEH */ #endif /* VFIO_H */ diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index cb9023d4f063..6612974c64bf 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -30,6 +30,9 @@ */ #define VFIO_DMA_CC_IOMMU 4 +/* Check if EEH is supported */ +#define VFIO_EEH 5 + /* * The IOCTL interface is designed for extensibility by embedding the * structure length (argsz) and flags into structures passed between @@ -455,6 +458,37 @@ struct vfio_iommu_spapr_tce_info { #define VFIO_IOMMU_SPAPR_TCE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12) +/* + * EEH PE operation struct provides ways to: + * - enable/disable EEH functionality; + * - unfreeze IO/DMA for frozen PE; + * - read PE state; + * - reset PE; + * - configure PE. + */ +struct vfio_eeh_pe_op { + __u32 argsz; + __u32 flags; + __u32 op; +}; + +#define VFIO_EEH_PE_DISABLE 0 /* Disable EEH functionality */ +#define VFIO_EEH_PE_ENABLE 1 /* Enable EEH functionality */ +#define VFIO_EEH_PE_UNFREEZE_IO 2 /* Enable IO for frozen PE */ +#define VFIO_EEH_PE_UNFREEZE_DMA 3 /* Enable DMA for frozen PE */ +#define VFIO_EEH_PE_GET_STATE 4 /* PE state retrieval */ +#define VFIO_EEH_PE_STATE_NORMAL 0 /* PE in functional state */ +#define VFIO_EEH_PE_STATE_RESET 1 /* PE reset in progress */ +#define VFIO_EEH_PE_STATE_STOPPED 2 /* Stopped DMA and IO */ +#define VFIO_EEH_PE_STATE_STOPPED_DMA 4 /* Stopped DMA only */ +#define VFIO_EEH_PE_STATE_UNAVAIL 5 /* State unavailable */ +#define VFIO_EEH_PE_RESET_DEACTIVATE 5 /* Deassert PE reset */ +#define VFIO_EEH_PE_RESET_HOT 6 /* Assert hot reset */ +#define VFIO_EEH_PE_RESET_FUNDAMENTAL 7 /* Assert fundamental reset */ +#define VFIO_EEH_PE_CONFIGURE 8 /* PE configuration */ + +#define VFIO_EEH_PE_OP _IO(VFIO_TYPE, VFIO_BASE + 21) + /* ***************************************************************** */ #endif /* _UAPIVFIO_H */