diff options
Diffstat (limited to 'drivers/vfio')
| -rw-r--r-- | drivers/vfio/Kconfig | 16 | ||||
| -rw-r--r-- | drivers/vfio/Makefile | 3 | ||||
| -rw-r--r-- | drivers/vfio/pci/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/vfio/pci/Makefile | 4 | ||||
| -rw-r--r-- | drivers/vfio/pci/vfio_pci.c | 579 | ||||
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_config.c | 1540 | ||||
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_intrs.c | 740 | ||||
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_private.h | 91 | ||||
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_rdwr.c | 269 | ||||
| -rw-r--r-- | drivers/vfio/vfio.c | 1420 | ||||
| -rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 753 |
11 files changed, 5423 insertions, 0 deletions
diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig new file mode 100644 index 000000000000..7cd5dec0abd1 --- /dev/null +++ b/drivers/vfio/Kconfig @@ -0,0 +1,16 @@ +config VFIO_IOMMU_TYPE1 + tristate + depends on VFIO + default n + +menuconfig VFIO + tristate "VFIO Non-Privileged userspace driver framework" + depends on IOMMU_API + select VFIO_IOMMU_TYPE1 if X86 + help + VFIO provides a framework for secure userspace device drivers. + See Documentation/vfio.txt for more details. + + If you don't know what to do here, say N. + +source "drivers/vfio/pci/Kconfig" diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile new file mode 100644 index 000000000000..2398d4a0e38b --- /dev/null +++ b/drivers/vfio/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_VFIO) += vfio.o +obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o +obj-$(CONFIG_VFIO_PCI) += pci/ diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig new file mode 100644 index 000000000000..5980758563eb --- /dev/null +++ b/drivers/vfio/pci/Kconfig @@ -0,0 +1,8 @@ +config VFIO_PCI + tristate "VFIO support for PCI devices" + depends on VFIO && PCI && EVENTFD + help + Support for the PCI VFIO bus driver. This is required to make + use of PCI drivers using the VFIO framework. + + If you don't know what to do here, say N. diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile new file mode 100644 index 000000000000..131079255fd9 --- /dev/null +++ b/drivers/vfio/pci/Makefile @@ -0,0 +1,4 @@ + +vfio-pci-y := vfio_pci.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o + +obj-$(CONFIG_VFIO_PCI) += vfio-pci.o diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c new file mode 100644 index 000000000000..6968b7232232 --- /dev/null +++ b/drivers/vfio/pci/vfio_pci.c @@ -0,0 +1,579 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + */ + +#include <linux/device.h> +#include <linux/eventfd.h> +#include <linux/interrupt.h> +#include <linux/iommu.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/notifier.h> +#include <linux/pci.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/uaccess.h> +#include <linux/vfio.h> + +#include "vfio_pci_private.h" + +#define DRIVER_VERSION "0.2" +#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" +#define DRIVER_DESC "VFIO PCI - User Level meta-driver" + +static bool nointxmask; +module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(nointxmask, + "Disable support for PCI 2.3 style INTx masking. If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag."); + +static int vfio_pci_enable(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + int ret; + u16 cmd; + u8 msix_pos; + + vdev->reset_works = (pci_reset_function(pdev) == 0); + pci_save_state(pdev); + vdev->pci_saved_state = pci_store_saved_state(pdev); + if (!vdev->pci_saved_state) + pr_debug("%s: Couldn't store %s saved state\n", + __func__, dev_name(&pdev->dev)); + + ret = vfio_config_init(vdev); + if (ret) + goto out; + + if (likely(!nointxmask)) + vdev->pci_2_3 = pci_intx_mask_supported(pdev); + + pci_read_config_word(pdev, PCI_COMMAND, &cmd); + if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) { + cmd &= ~PCI_COMMAND_INTX_DISABLE; + pci_write_config_word(pdev, PCI_COMMAND, cmd); + } + + msix_pos = pci_find_capability(pdev, PCI_CAP_ID_MSIX); + if (msix_pos) { + u16 flags; + u32 table; + + pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags); + pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table); + + vdev->msix_bar = table & PCI_MSIX_FLAGS_BIRMASK; + vdev->msix_offset = table & ~PCI_MSIX_FLAGS_BIRMASK; + vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16; + } else + vdev->msix_bar = 0xFF; + + ret = pci_enable_device(pdev); + if (ret) + goto out; + + return ret; + +out: + kfree(vdev->pci_saved_state); + vdev->pci_saved_state = NULL; + vfio_config_free(vdev); + return ret; +} + +static void vfio_pci_disable(struct vfio_pci_device *vdev) +{ + int bar; + + pci_disable_device(vdev->pdev); + + vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE | + VFIO_IRQ_SET_ACTION_TRIGGER, + vdev->irq_type, 0, 0, NULL); + + vdev->virq_disabled = false; + + vfio_config_free(vdev); + + pci_reset_function(vdev->pdev); + + if (pci_load_and_free_saved_state(vdev->pdev, + &vdev->pci_saved_state) == 0) + pci_restore_state(vdev->pdev); + else + pr_info("%s: Couldn't reload %s saved state\n", + __func__, dev_name(&vdev->pdev->dev)); + + for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) { + if (!vdev->barmap[bar]) + continue; + pci_iounmap(vdev->pdev, vdev->barmap[bar]); + pci_release_selected_regions(vdev->pdev, 1 << bar); + vdev->barmap[bar] = NULL; + } +} + +static void vfio_pci_release(void *device_data) +{ + struct vfio_pci_device *vdev = device_data; + + if (atomic_dec_and_test(&vdev->refcnt)) + vfio_pci_disable(vdev); + + module_put(THIS_MODULE); +} + +static int vfio_pci_open(void *device_data) +{ + struct vfio_pci_device *vdev = device_data; + + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + + if (atomic_inc_return(&vdev->refcnt) == 1) { + int ret = vfio_pci_enable(vdev); + if (ret) { + module_put(THIS_MODULE); + return ret; + } + } + + return 0; +} + +static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) +{ + if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) { + u8 pin; + pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin); + if (pin) + return 1; + + } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) { + u8 pos; + u16 flags; + + pos = pci_find_capability(vdev->pdev, PCI_CAP_ID_MSI); + if (pos) { + pci_read_config_word(vdev->pdev, + pos + PCI_MSI_FLAGS, &flags); + + return 1 << (flags & PCI_MSI_FLAGS_QMASK); + } + } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) { + u8 pos; + u16 flags; + + pos = pci_find_capability(vdev->pdev, PCI_CAP_ID_MSIX); + if (pos) { + pci_read_config_word(vdev->pdev, + pos + PCI_MSIX_FLAGS, &flags); + + return (flags & PCI_MSIX_FLAGS_QSIZE) + 1; + } + } + + return 0; +} + +static long vfio_pci_ioctl(void *device_data, + unsigned int cmd, unsigned long arg) +{ + struct vfio_pci_device *vdev = device_data; + unsigned long minsz; + + if (cmd == VFIO_DEVICE_GET_INFO) { + struct vfio_device_info info; + + minsz = offsetofend(struct vfio_device_info, num_irqs); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + info.flags = VFIO_DEVICE_FLAGS_PCI; + + if (vdev->reset_works) + info.flags |= VFIO_DEVICE_FLAGS_RESET; + + info.num_regions = VFIO_PCI_NUM_REGIONS; + info.num_irqs = VFIO_PCI_NUM_IRQS; + + return copy_to_user((void __user *)arg, &info, minsz); + + } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) { + struct pci_dev *pdev = vdev->pdev; + struct vfio_region_info info; + + minsz = offsetofend(struct vfio_region_info, offset); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + switch (info.index) { + case VFIO_PCI_CONFIG_REGION_INDEX: + info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); + info.size = pdev->cfg_size; + info.flags = VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE; + break; + case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: + info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); + info.size = pci_resource_len(pdev, info.index); + if (!info.size) { + info.flags = 0; + break; + } + + info.flags = VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE; + if (pci_resource_flags(pdev, info.index) & + IORESOURCE_MEM && info.size >= PAGE_SIZE) + info.flags |= VFIO_REGION_INFO_FLAG_MMAP; + break; + case VFIO_PCI_ROM_REGION_INDEX: + { + void __iomem *io; + size_t size; + + info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); + info.flags = 0; + + /* Report the BAR size, not the ROM size */ + info.size = pci_resource_len(pdev, info.index); + if (!info.size) + break; + + /* Is it really there? */ + io = pci_map_rom(pdev, &size); + if (!io || !size) { + info.size = 0; + break; + } + pci_unmap_rom(pdev, io); + + info.flags = VFIO_REGION_INFO_FLAG_READ; + break; + } + default: + return -EINVAL; + } + + return copy_to_user((void __user *)arg, &info, minsz); + + } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) { + struct vfio_irq_info info; + + minsz = offsetofend(struct vfio_irq_info, count); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS) + return -EINVAL; + + info.flags = VFIO_IRQ_INFO_EVENTFD; + + info.count = vfio_pci_get_irq_count(vdev, info.index); + + if (info.index == VFIO_PCI_INTX_IRQ_INDEX) + info.flags |= (VFIO_IRQ_INFO_MASKABLE | + VFIO_IRQ_INFO_AUTOMASKED); + else + info.flags |= VFIO_IRQ_INFO_NORESIZE; + + return copy_to_user((void __user *)arg, &info, minsz); + + } else if (cmd == VFIO_DEVICE_SET_IRQS) { + struct vfio_irq_set hdr; + u8 *data = NULL; + int ret = 0; + + minsz = offsetofend(struct vfio_irq_set, count); + + if (copy_from_user(&hdr, (void __user *)arg, minsz)) + return -EFAULT; + + if (hdr.argsz < minsz || hdr.index >= VFIO_PCI_NUM_IRQS || + hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK | + VFIO_IRQ_SET_ACTION_TYPE_MASK)) + return -EINVAL; + + if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) { + size_t size; + + if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL) + size = sizeof(uint8_t); + else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD) + size = sizeof(int32_t); + else + return -EINVAL; + + if (hdr.argsz - minsz < hdr.count * size || + hdr.count > vfio_pci_get_irq_count(vdev, hdr.index)) + return -EINVAL; + + data = kmalloc(hdr.count * size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + if (copy_from_user(data, (void __user *)(arg + minsz), + hdr.count * size)) { + kfree(data); + return -EFAULT; + } + } + + mutex_lock(&vdev->igate); + + ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index, + hdr.start, hdr.count, data); + + mutex_unlock(&vdev->igate); + kfree(data); + + return ret; + + } else if (cmd == VFIO_DEVICE_RESET) + return vdev->reset_works ? + pci_reset_function(vdev->pdev) : -EINVAL; + + return -ENOTTY; +} + +static ssize_t vfio_pci_read(void *device_data, char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + struct vfio_pci_device *vdev = device_data; + struct pci_dev *pdev = vdev->pdev; + + if (index >= VFIO_PCI_NUM_REGIONS) + return -EINVAL; + + if (index == VFIO_PCI_CONFIG_REGION_INDEX) + return vfio_pci_config_readwrite(vdev, buf, count, ppos, false); + else if (index == VFIO_PCI_ROM_REGION_INDEX) + return vfio_pci_mem_readwrite(vdev, buf, count, ppos, false); + else if (pci_resource_flags(pdev, index) & IORESOURCE_IO) + return vfio_pci_io_readwrite(vdev, buf, count, ppos, false); + else if (pci_resource_flags(pdev, index) & IORESOURCE_MEM) + return vfio_pci_mem_readwrite(vdev, buf, count, ppos, false); + + return -EINVAL; +} + +static ssize_t vfio_pci_write(void *device_data, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + struct vfio_pci_device *vdev = device_data; + struct pci_dev *pdev = vdev->pdev; + + if (index >= VFIO_PCI_NUM_REGIONS) + return -EINVAL; + + if (index == VFIO_PCI_CONFIG_REGION_INDEX) + return vfio_pci_config_readwrite(vdev, (char __user *)buf, + count, ppos, true); + else if (index == VFIO_PCI_ROM_REGION_INDEX) + return -EINVAL; + else if (pci_resource_flags(pdev, index) & IORESOURCE_IO) + return vfio_pci_io_readwrite(vdev, (char __user *)buf, + count, ppos, true); + else if (pci_resource_flags(pdev, index) & IORESOURCE_MEM) { + return vfio_pci_mem_readwrite(vdev, (char __user *)buf, + count, ppos, true); + } + + return -EINVAL; +} + +static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) +{ + struct vfio_pci_device *vdev = device_data; + struct pci_dev *pdev = vdev->pdev; + unsigned int index; + u64 phys_len, req_len, pgoff, req_start, phys; + int ret; + + index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT); + + if (vma->vm_end < vma->vm_start) + return -EINVAL; + if ((vma->vm_flags & VM_SHARED) == 0) + return -EINVAL; + if (index >= VFIO_PCI_ROM_REGION_INDEX) + return -EINVAL; + if (!(pci_resource_flags(pdev, index) & IORESOURCE_MEM)) + return -EINVAL; + + phys_len = pci_resource_len(pdev, index); + req_len = vma->vm_end - vma->vm_start; + pgoff = vma->vm_pgoff & + ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1); + req_start = pgoff << PAGE_SHIFT; + + if (phys_len < PAGE_SIZE || req_start + req_len > phys_len) + return -EINVAL; + + if (index == vdev->msix_bar) { + /* + * Disallow mmaps overlapping the MSI-X table; users don't + * get to touch this directly. We could find somewhere + * else to map the overlap, but page granularity is only + * a recommendation, not a requirement, so the user needs + * to know which bits are real. Requiring them to mmap + * around the table makes that clear. + */ + + /* If neither entirely above nor below, then it overlaps */ + if (!(req_start >= vdev->msix_offset + vdev->msix_size || + req_start + req_len <= vdev->msix_offset)) + return -EINVAL; + } + + /* + * Even though we don't make use of the barmap for the mmap, + * we need to request the region and the barmap tracks that. + */ + if (!vdev->barmap[index]) { + ret = pci_request_selected_regions(pdev, + 1 << index, "vfio-pci"); + if (ret) + return ret; + + vdev->barmap[index] = pci_iomap(pdev, index, 0); + } + + vma->vm_private_data = vdev; + vma->vm_flags |= (VM_IO | VM_RESERVED); + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + phys = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff; + + return remap_pfn_range(vma, vma->vm_start, phys, + req_len, vma->vm_page_prot); +} + +static const struct vfio_device_ops vfio_pci_ops = { + .name = "vfio-pci", + .open = vfio_pci_open, + .release = vfio_pci_release, + .ioctl = vfio_pci_ioctl, + .read = vfio_pci_read, + .write = vfio_pci_write, + .mmap = vfio_pci_mmap, +}; + +static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + u8 type; + struct vfio_pci_device *vdev; + struct iommu_group *group; + int ret; + + pci_read_config_byte(pdev, PCI_HEADER_TYPE, &type); + if ((type & PCI_HEADER_TYPE) != PCI_HEADER_TYPE_NORMAL) + return -EINVAL; + + group = iommu_group_get(&pdev->dev); + if (!group) + return -EINVAL; + + vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); + if (!vdev) { + iommu_group_put(group); + return -ENOMEM; + } + + vdev->pdev = pdev; + vdev->irq_type = VFIO_PCI_NUM_IRQS; + mutex_init(&vdev->igate); + spin_lock_init(&vdev->irqlock); + atomic_set(&vdev->refcnt, 0); + + ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev); + if (ret) { + iommu_group_put(group); + kfree(vdev); + } + + return ret; +} + +static void vfio_pci_remove(struct pci_dev *pdev) +{ + struct vfio_pci_device *vdev; + + vdev = vfio_del_group_dev(&pdev->dev); + if (!vdev) + return; + + iommu_group_put(pdev->dev.iommu_group); + kfree(vdev); +} + +static struct pci_driver vfio_pci_driver = { + .name = "vfio-pci", + .id_table = NULL, /* only dynamic ids */ + .probe = vfio_pci_probe, + .remove = vfio_pci_remove, +}; + +static void __exit vfio_pci_cleanup(void) +{ + pci_unregister_driver(&vfio_pci_driver); + vfio_pci_virqfd_exit(); + vfio_pci_uninit_perm_bits(); +} + +static int __init vfio_pci_init(void) +{ + int ret; + + /* Allocate shared config space permision data used by all devices */ + ret = vfio_pci_init_perm_bits(); + if (ret) + return ret; + + /* Start the virqfd cleanup handler */ + ret = vfio_pci_virqfd_init(); + if (ret) + goto out_virqfd; + + /* Register and scan for devices */ + ret = pci_register_driver(&vfio_pci_driver); + if (ret) + goto out_driver; + + return 0; + +out_virqfd: + vfio_pci_virqfd_exit(); +out_driver: + vfio_pci_uninit_perm_bits(); + return ret; +} + +module_init(vfio_pci_init); +module_exit(vfio_pci_cleanup); + +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c new file mode 100644 index 000000000000..8b8f7d11e102 --- /dev/null +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -0,0 +1,1540 @@ +/* + * VFIO PCI config space virtualization + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + */ + +/* + * This code handles reading and writing of PCI configuration registers. + * This is hairy because we want to allow a lot of flexibility to the + * user driver, but cannot trust it with all of the config fields. + * Tables determine which fields can be read and written, as well as + * which fields are 'virtualized' - special actions and translations to + * make it appear to the user that he has control, when in fact things + * must be negotiated with the underlying OS. + */ + +#include <linux/fs.h> +#include <linux/pci.h> +#include <linux/uaccess.h> +#include <linux/vfio.h> + +#include "vfio_pci_private.h" + +#define PCI_CFG_SPACE_SIZE 256 + +/* Useful "pseudo" capabilities */ +#define PCI_CAP_ID_BASIC 0 +#define PCI_CAP_ID_INVALID 0xFF + +#define is_bar(offset) \ + ((offset >= PCI_BASE_ADDRESS_0 && offset < PCI_BASE_ADDRESS_5 + 4) || \ + (offset >= PCI_ROM_ADDRESS && offset < PCI_ROM_ADDRESS + 4)) + +/* + * Lengths of PCI Config Capabilities + * 0: Removed from the user visible capability list + * FF: Variable length + */ +static u8 pci_cap_length[] = { + [PCI_CAP_ID_BASIC] = PCI_STD_HEADER_SIZEOF, /* pci config header */ + [PCI_CAP_ID_PM] = PCI_PM_SIZEOF, + [PCI_CAP_ID_AGP] = PCI_AGP_SIZEOF, + [PCI_CAP_ID_VPD] = PCI_CAP_VPD_SIZEOF, + [PCI_CAP_ID_SLOTID] = 0, /* bridge - don't care */ + [PCI_CAP_ID_MSI] = 0xFF, /* 10, 14, 20, or 24 */ + [PCI_CAP_ID_CHSWP] = 0, /* cpci - not yet */ + [PCI_CAP_ID_PCIX] = 0xFF, /* 8 or 24 */ + [PCI_CAP_ID_HT] = 0xFF, /* hypertransport */ + [PCI_CAP_ID_VNDR] = 0xFF, /* variable */ + [PCI_CAP_ID_DBG] = 0, /* debug - don't care */ + [PCI_CAP_ID_CCRC] = 0, /* cpci - not yet */ + [PCI_CAP_ID_SHPC] = 0, /* hotswap - not yet */ + [PCI_CAP_ID_SSVID] = 0, /* bridge - don't care */ + [PCI_CAP_ID_AGP3] = 0, /* AGP8x - not yet */ + [PCI_CAP_ID_SECDEV] = 0, /* secure device not yet */ + [PCI_CAP_ID_EXP] = 0xFF, /* 20 or 44 */ + [PCI_CAP_ID_MSIX] = PCI_CAP_MSIX_SIZEOF, + [PCI_CAP_ID_SATA] = 0xFF, + [PCI_CAP_ID_AF] = PCI_CAP_AF_SIZEOF, +}; + +/* + * Lengths of PCIe/PCI-X Extended Config Capabilities + * 0: Removed or masked from the user visible capabilty list + * FF: Variable length + */ +static u16 pci_ext_cap_length[] = { + [PCI_EXT_CAP_ID_ERR] = PCI_ERR_ROOT_COMMAND, + [PCI_EXT_CAP_ID_VC] = 0xFF, + [PCI_EXT_CAP_ID_DSN] = PCI_EXT_CAP_DSN_SIZEOF, + [PCI_EXT_CAP_ID_PWR] = PCI_EXT_CAP_PWR_SIZEOF, + [PCI_EXT_CAP_ID_RCLD] = 0, /* root only - don't care */ + [PCI_EXT_CAP_ID_RCILC] = 0, /* root only - don't care */ + [PCI_EXT_CAP_ID_RCEC] = 0, /* root only - don't care */ + [PCI_EXT_CAP_ID_MFVC] = 0xFF, + [PCI_EXT_CAP_ID_VC9] = 0xFF, /* same as CAP_ID_VC */ + [PCI_EXT_CAP_ID_RCRB] = 0, /* root only - don't care */ + [PCI_EXT_CAP_ID_VNDR] = 0xFF, + [PCI_EXT_CAP_ID_CAC] = 0, /* obsolete */ + [PCI_EXT_CAP_ID_ACS] = 0xFF, + [PCI_EXT_CAP_ID_ARI] = PCI_EXT_CAP_ARI_SIZEOF, + [PCI_EXT_CAP_ID_ATS] = PCI_EXT_CAP_ATS_SIZEOF, + [PCI_EXT_CAP_ID_SRIOV] = PCI_EXT_CAP_SRIOV_SIZEOF, + [PCI_EXT_CAP_ID_MRIOV] = 0, /* not yet */ + [PCI_EXT_CAP_ID_MCAST] = PCI_EXT_CAP_MCAST_ENDPOINT_SIZEOF, + [PCI_EXT_CAP_ID_PRI] = PCI_EXT_CAP_PRI_SIZEOF, + [PCI_EXT_CAP_ID_AMD_XXX] = 0, /* not yet */ + [PCI_EXT_CAP_ID_REBAR] = 0xFF, + [PCI_EXT_CAP_ID_DPA] = 0xFF, + [PCI_EXT_CAP_ID_TPH] = 0xFF, + [PCI_EXT_CAP_ID_LTR] = PCI_EXT_CAP_LTR_SIZEOF, + [PCI_EXT_CAP_ID_SECPCI] = 0, /* not yet */ + [PCI_EXT_CAP_ID_PMUX] = 0, /* not yet */ + [PCI_EXT_CAP_ID_PASID] = 0, /* not yet */ +}; + +/* + * Read/Write Permission Bits - one bit for each bit in capability + * Any field can be read if it exists, but what is read depends on + * whether the field is 'virtualized', or just pass thru to the + * hardware. Any virtualized field is also virtualized for writes. + * Writes are only permitted if they have a 1 bit here. + */ +struct perm_bits { + u8 *virt; /* read/write virtual data, not hw */ + u8 *write; /* writeable bits */ + int (*readfn)(struct vfio_pci_device *vdev, int pos, int count, + struct perm_bits *perm, int offset, __le32 *val); + int (*writefn)(struct vfio_pci_device *vdev, int pos, int count, + struct perm_bits *perm, int offset, __le32 val); +}; + +#define NO_VIRT 0 +#define ALL_VIRT 0xFFFFFFFFU +#define NO_WRITE 0 +#define ALL_WRITE 0xFFFFFFFFU + +static int vfio_user_config_read(struct pci_dev *pdev, int offset, + __le32 *val, int count) +{ + int ret = -EINVAL; + u32 tmp_val = 0; + + switch (count) { + case 1: + { + u8 tmp; + ret = pci_user_read_config_byte(pdev, offset, &tmp); + tmp_val = tmp; + break; + } + case 2: + { + u16 tmp; + ret = pci_user_read_config_word(pdev, offset, &tmp); + tmp_val = tmp; + break; + } + case 4: + ret = pci_user_read_config_dword(pdev, offset, &tmp_val); + break; + } + + *val = cpu_to_le32(tmp_val); + + return pcibios_err_to_errno(ret); +} + +static int vfio_user_config_write(struct pci_dev *pdev, int offset, + __le32 val, int count) +{ + int ret = -EINVAL; + u32 tmp_val = le32_to_cpu(val); + + switch (count) { + case 1: + ret = pci_user_write_config_byte(pdev, offset, tmp_val); + break; + case 2: + ret = pci_user_write_config_word(pdev, offset, tmp_val); + break; + case 4: + ret = pci_user_write_config_dword(pdev, offset, tmp_val); + break; + } + + return pcibios_err_to_errno(ret); +} + +static int vfio_default_config_read(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 *val) +{ + __le32 virt = 0; + + memcpy(val, vdev->vconfig + pos, count); + + memcpy(&virt, perm->virt + offset, count); + + /* Any non-virtualized bits? */ + if (cpu_to_le32(~0U >> (32 - (count * 8))) != virt) { + struct pci_dev *pdev = vdev->pdev; + __le32 phys_val = 0; + int ret; + + ret = vfio_user_config_read(pdev, pos, &phys_val, count); + if (ret) + return ret; + + *val = (phys_val & ~virt) | (*val & virt); + } + + return count; +} + +static int vfio_default_config_write(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 val) +{ + __le32 virt = 0, write = 0; + + memcpy(&write, perm->write + offset, count); + + if (!write) + return count; /* drop, no writable bits */ + + memcpy(&virt, perm->virt + offset, count); + + /* Virtualized and writable bits go to vconfig */ + if (write & virt) { + __le32 virt_val = 0; + + memcpy(&virt_val, vdev->vconfig + pos, count); + + virt_val &= ~(write & virt); + virt_val |= (val & (write & virt)); + + memcpy(vdev->vconfig + pos, &virt_val, count); + } + + /* Non-virtualzed and writable bits go to hardware */ + if (write & ~virt) { + struct pci_dev *pdev = vdev->pdev; + __le32 phys_val = 0; + int ret; + + ret = vfio_user_config_read(pdev, pos, &phys_val, count); + if (ret) + return ret; + + phys_val &= ~(write & ~virt); + phys_val |= (val & (write & ~virt)); + + ret = vfio_user_config_write(pdev, pos, phys_val, count); + if (ret) + return ret; + } + + return count; +} + +/* Allow direct read from hardware, except for capability next pointer */ +static int vfio_direct_config_read(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 *val) +{ + int ret; + + ret = vfio_user_config_read(vdev->pdev, pos, val, count); + if (ret) + return pcibios_err_to_errno(ret); + + if (pos >= PCI_CFG_SPACE_SIZE) { /* Extended cap header mangling */ + if (offset < 4) + memcpy(val, vdev->vconfig + pos, count); + } else if (pos >= PCI_STD_HEADER_SIZEOF) { /* Std cap mangling */ + if (offset == PCI_CAP_LIST_ID && count > 1) + memcpy(val, vdev->vconfig + pos, + min(PCI_CAP_FLAGS, count)); + else if (offset == PCI_CAP_LIST_NEXT) + memcpy(val, vdev->vconfig + pos, 1); + } + + return count; +} + +static int vfio_direct_config_write(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 val) +{ + int ret; + + ret = vfio_user_config_write(vdev->pdev, pos, val, count); + if (ret) + return ret; + + return count; +} + +/* Default all regions to read-only, no-virtualization */ +static struct perm_bits cap_perms[PCI_CAP_ID_MAX + 1] = { + [0 ... PCI_CAP_ID_MAX] = { .readfn = vfio_direct_config_read } +}; +static struct perm_bits ecap_perms[PCI_EXT_CAP_ID_MAX + 1] = { + [0 ... PCI_EXT_CAP_ID_MAX] = { .readfn = vfio_direct_config_read } +}; + +static void free_perm_bits(struct perm_bits *perm) +{ + kfree(perm->virt); + kfree(perm->write); + perm->virt = NULL; + perm->write = NULL; +} + +static int alloc_perm_bits(struct perm_bits *perm, int size) +{ + /* + * Round up all permission bits to the next dword, this lets us + * ignore whether a read/write exceeds the defined capability + * structure. We can do this because: + * - Standard config space is already dword aligned + * - Capabilities are all dword alinged (bits 0:1 of next reserved) + * - Express capabilities defined as dword aligned + */ + size = round_up(size, 4); + + /* + * Zero state is + * - All Readable, None Writeable, None Virtualized + */ + perm->virt = kzalloc(size, GFP_KERNEL); + perm->write = kzalloc(size, GFP_KERNEL); + if (!perm->virt || !perm->write) { + free_perm_bits(perm); + return -ENOMEM; + } + + perm->readfn = vfio_default_config_read; + perm->writefn = vfio_default_config_write; + + return 0; +} + +/* + * Helper functions for filling in permission tables + */ +static inline void p_setb(struct perm_bits *p, int off, u8 virt, u8 write) +{ + p->virt[off] = virt; + p->write[off] = write; +} + +/* Handle endian-ness - pci and tables are little-endian */ +static inline void p_setw(struct perm_bits *p, int off, u16 virt, u16 write) +{ + *(__le16 *)(&p->virt[off]) = cpu_to_le16(virt); + *(__le16 *)(&p->write[off]) = cpu_to_le16(write); +} + +/* Handle endian-ness - pci and tables are little-endian */ +static inline void p_setd(struct perm_bits *p, int off, u32 virt, u32 write) +{ + *(__le32 *)(&p->virt[off]) = cpu_to_le32(virt); + *(__le32 *)(&p->write[off]) = cpu_to_le32(write); +} + +/* + * Restore the *real* BARs after we detect a FLR or backdoor reset. + * (backdoor = some device specific technique that we didn't catch) + */ +static void vfio_bar_restore(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + u32 *rbar = vdev->rbar; + int i; + + if (pdev->is_virtfn) + return; + + pr_info("%s: %s reset recovery - restoring bars\n", + __func__, dev_name(&pdev->dev)); + + for (i = PCI_BASE_ADDRESS_0; i <= PCI_BASE_ADDRESS_5; i += 4, rbar++) + pci_user_write_config_dword(pdev, i, *rbar); + + pci_user_write_config_dword(pdev, PCI_ROM_ADDRESS, *rbar); +} + +static __le32 vfio_generate_bar_flags(struct pci_dev *pdev, int bar) +{ + unsigned long flags = pci_resource_flags(pdev, bar); + u32 val; + + if (flags & IORESOURCE_IO) + return cpu_to_le32(PCI_BASE_ADDRESS_SPACE_IO); + + val = PCI_BASE_ADDRESS_SPACE_MEMORY; + + if (flags & IORESOURCE_PREFETCH) + val |= PCI_BASE_ADDRESS_MEM_PREFETCH; + + if (flags & IORESOURCE_MEM_64) + val |= PCI_BASE_ADDRESS_MEM_TYPE_64; + + return cpu_to_le32(val); +} + +/* + * Pretend we're hardware and tweak the values of the *virtual* PCI BARs + * to reflect the hardware capabilities. This implements BAR sizing. + */ +static void vfio_bar_fixup(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + int i; + __le32 *bar; + u64 mask; + + bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0]; + + for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) { + if (!pci_resource_start(pdev, i)) { + *bar = 0; /* Unmapped by host = unimplemented to user */ + continue; + } + + mask = ~(pci_resource_len(pdev, i) - 1); + + *bar &= cpu_to_le32((u32)mask); + *bar |= vfio_generate_bar_flags(pdev, i); + + if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) { + bar++; + *bar &= cpu_to_le32((u32)(mask >> 32)); + i++; + } + } + + bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS]; + + /* + * NB. we expose the actual BAR size here, regardless of whether + * we can read it. When we report the REGION_INFO for the ROM + * we report what PCI tells us is the actual ROM size. + */ + if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) { + mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1); + mask |= PCI_ROM_ADDRESS_ENABLE; + *bar &= cpu_to_le32((u32)mask); + } else + *bar = 0; + + vdev->bardirty = false; +} + +static int vfio_basic_config_read(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 *val) +{ + if (is_bar(offset)) /* pos == offset for basic config */ + vfio_bar_fixup(vdev); + + count = vfio_default_config_read(vdev, pos, count, perm, offset, val); + + /* Mask in virtual memory enable for SR-IOV devices */ + if (offset == PCI_COMMAND && vdev->pdev->is_virtfn) { + u16 cmd = le16_to_cpu(*(__le16 *)&vdev->vconfig[PCI_COMMAND]); + u32 tmp_val = le32_to_cpu(*val); + + tmp_val |= cmd & PCI_COMMAND_MEMORY; + *val = cpu_to_le32(tmp_val); + } + + return count; +} + +static int vfio_basic_config_write(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 val) +{ + struct pci_dev *pdev = vdev->pdev; + __le16 *virt_cmd; + u16 new_cmd = 0; + int ret; + + virt_cmd = (__le16 *)&vdev->vconfig[PCI_COMMAND]; + + if (offset == PCI_COMMAND) { + bool phys_mem, virt_mem, new_mem, phys_io, virt_io, new_io; + u16 phys_cmd; + + ret = pci_user_read_config_word(pdev, PCI_COMMAND, &phys_cmd); + if (ret) + return ret; + + new_cmd = le32_to_cpu(val); + + phys_mem = !!(phys_cmd & PCI_COMMAND_MEMORY); + virt_mem = !!(le16_to_cpu(*virt_cmd) & PCI_COMMAND_MEMORY); + new_mem = !!(new_cmd & PCI_COMMAND_MEMORY); + + phys_io = !!(phys_cmd & PCI_COMMAND_IO); + virt_io = !!(le16_to_cpu(*virt_cmd) & PCI_COMMAND_IO); + new_io = !!(new_cmd & PCI_COMMAND_IO); + + /* + * If the user is writing mem/io enable (new_mem/io) and we + * think it's already enabled (virt_mem/io), but the hardware + * shows it disabled (phys_mem/io, then the device has + * undergone some kind of backdoor reset and needs to be + * restored before we allow it to enable the bars. + * SR-IOV devices will trigger this, but we catch them later + */ + if ((new_mem && virt_mem && !phys_mem) || + (new_io && virt_io && !phys_io)) + vfio_bar_restore(vdev); + } + + count = vfio_default_config_write(vdev, pos, count, perm, offset, val); + if (count < 0) + return count; + + /* + * Save current memory/io enable bits in vconfig to allow for + * the test above next time. + */ + if (offset == PCI_COMMAND) { + u16 mask = PCI_COMMAND_MEMORY | PCI_COMMAND_IO; + + *virt_cmd &= cpu_to_le16(~mask); + *virt_cmd |= cpu_to_le16(new_cmd & mask); + } + + /* Emulate INTx disable */ + if (offset >= PCI_COMMAND && offset <= PCI_COMMAND + 1) { + bool virt_intx_disable; + + virt_intx_disable = !!(le16_to_cpu(*virt_cmd) & + PCI_COMMAND_INTX_DISABLE); + + if (virt_intx_disable && !vdev->virq_disabled) { + vdev->virq_disabled = true; + vfio_pci_intx_mask(vdev); + } else if (!virt_intx_disable && vdev->virq_disabled) { + vdev->virq_disabled = false; + vfio_pci_intx_unmask(vdev); + } + } + + if (is_bar(offset)) + vdev->bardirty = true; + + return count; +} + +/* Permissions for the Basic PCI Header */ +static int __init init_pci_cap_basic_perm(struct perm_bits *perm) +{ + if (alloc_perm_bits(perm, PCI_STD_HEADER_SIZEOF)) + return -ENOMEM; + + perm->readfn = vfio_basic_config_read; + perm->writefn = vfio_basic_config_write; + + /* Virtualized for SR-IOV functions, which just have FFFF */ + p_setw(perm, PCI_VENDOR_ID, (u16)ALL_VIRT, NO_WRITE); + p_setw(perm, PCI_DEVICE_ID, (u16)ALL_VIRT, NO_WRITE); + + /* + * Virtualize INTx disable, we use it internally for interrupt + * control and can emulate it for non-PCI 2.3 devices. + */ + p_setw(perm, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE, (u16)ALL_WRITE); + + /* Virtualize capability list, we might want to skip/disable */ + p_setw(perm, PCI_STATUS, PCI_STATUS_CAP_LIST, NO_WRITE); + + /* No harm to write */ + p_setb(perm, PCI_CACHE_LINE_SIZE, NO_VIRT, (u8)ALL_WRITE); + p_setb(perm, PCI_LATENCY_TIMER, NO_VIRT, (u8)ALL_WRITE); + p_setb(perm, PCI_BIST, NO_VIRT, (u8)ALL_WRITE); + + /* Virtualize all bars, can't touch the real ones */ + p_setd(perm, PCI_BASE_ADDRESS_0, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_BASE_ADDRESS_1, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_BASE_ADDRESS_2, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_BASE_ADDRESS_3, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_BASE_ADDRESS_4, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_BASE_ADDRESS_5, ALL_VIRT, ALL_WRITE); + p_setd(perm, PCI_ROM_ADDRESS, ALL_VIRT, ALL_WRITE); + + /* Allow us to adjust capability chain */ + p_setb(perm, PCI_CAPABILITY_LIST, (u8)ALL_VIRT, NO_WRITE); + + /* Sometimes used by sw, just virtualize */ + p_setb(perm, PCI_INTERRUPT_LINE, (u8)ALL_VIRT, (u8)ALL_WRITE); + return 0; +} + +/* Permissions for the Power Management capability */ +static int __init init_pci_cap_pm_perm(struct perm_bits *perm) +{ + if (alloc_perm_bits(perm, pci_cap_length[PCI_CAP_ID_PM])) + return -ENOMEM; + + /* + * We always virtualize the next field so we can remove + * capabilities from the chain if we want to. + */ + p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); + + /* + * Power management is defined *per function*, + * so we let the user write this + */ + p_setd(perm, PCI_PM_CTRL, NO_VIRT, ALL_WRITE); + return 0; +} + +/* Permissions for PCI-X capability */ +static int __init init_pci_cap_pcix_perm(struct perm_bits *perm) +{ + /* Alloc 24, but only 8 are used in v0 */ + if (alloc_perm_bits(perm, PCI_CAP_PCIX_SIZEOF_V2)) + return -ENOMEM; + + p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); + + p_setw(perm, PCI_X_CMD, NO_VIRT, (u16)ALL_WRITE); + p_setd(perm, PCI_X_ECC_CSR, NO_VIRT, ALL_WRITE); + return 0; +} + +/* Permissions for PCI Express capability */ +static int __init init_pci_cap_exp_perm(struct perm_bits *perm) +{ + /* Alloc larger of two possible sizes */ + if (alloc_perm_bits(perm, PCI_CAP_EXP_ENDPOINT_SIZEOF_V2)) + return -ENOMEM; + + p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); + + /* + * Allow writes to device control fields (includes FLR!) + * but not to devctl_phantom which could confuse IOMMU + * or to the ARI bit in devctl2 which is set at probe time + */ + p_setw(perm, PCI_EXP_DEVCTL, NO_VIRT, ~PCI_EXP_DEVCTL_PHANTOM); + p_setw(perm, PCI_EXP_DEVCTL2, NO_VIRT, ~PCI_EXP_DEVCTL2_ARI); + return 0; +} + +/* Permissions for Advanced Function capability */ +static int __init init_pci_cap_af_perm(struct perm_bits *perm) +{ + if (alloc_perm_bits(perm, pci_cap_length[PCI_CAP_ID_AF])) + return -ENOMEM; + + p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); + p_setb(perm, PCI_AF_CTRL, NO_VIRT, PCI_AF_CTRL_FLR); + return 0; +} + +/* Permissions for Advanced Error Reporting extended capability */ +static int __init init_pci_ext_cap_err_perm(struct perm_bits *perm) +{ + u32 mask; + + if (alloc_perm_bits(perm, pci_ext_cap_length[PCI_EXT_CAP_ID_ERR])) + return -ENOMEM; + + /* + * Virtualize the first dword of all express capabilities + * because it includes the next pointer. This lets us later + * remove capabilities from the chain if we need to. + */ + p_setd(perm, 0, ALL_VIRT, NO_WRITE); + + /* Writable bits mask */ + mask = PCI_ERR_UNC_TRAIN | /* Training */ + PCI_ERR_UNC_DLP | /* Data Link Protocol */ + PCI_ERR_UNC_SURPDN | /* Surprise Down */ + PCI_ERR_UNC_POISON_TLP | /* Poisoned TLP */ + PCI_ERR_UNC_FCP | /* Flow Control Protocol */ + PCI_ERR_UNC_COMP_TIME | /* Completion Timeout */ + PCI_ERR_UNC_COMP_ABORT | /* Completer Abort */ + PCI_ERR_UNC_UNX_COMP | /* Unexpected Completion */ + PCI_ERR_UNC_RX_OVER | /* Receiver Overflow */ + PCI_ERR_UNC_MALF_TLP | /* Malformed TLP */ + PCI_ERR_UNC_ECRC | /* ECRC Error Status */ + PCI_ERR_UNC_UNSUP | /* Unsupported Request */ + PCI_ERR_UNC_ACSV | /* ACS Violation */ + PCI_ERR_UNC_INTN | /* internal error */ + PCI_ERR_UNC_MCBTLP | /* MC blocked TLP */ + PCI_ERR_UNC_ATOMEG | /* Atomic egress blocked */ + PCI_ERR_UNC_TLPPRE; /* TLP prefix blocked */ + p_setd(perm, PCI_ERR_UNCOR_STATUS, NO_VIRT, mask); + p_setd(perm, PCI_ERR_UNCOR_MASK, NO_VIRT, mask); + p_setd(perm, PCI_ERR_UNCOR_SEVER, NO_VIRT, mask); + + mask = PCI_ERR_COR_RCVR | /* Receiver Error Status */ + PCI_ERR_COR_BAD_TLP | /* Bad TLP Status */ + PCI_ERR_COR_BAD_DLLP | /* Bad DLLP Status */ + PCI_ERR_COR_REP_ROLL | /* REPLAY_NUM Rollover */ + PCI_ERR_COR_REP_TIMER | /* Replay Timer Timeout */ + PCI_ERR_COR_ADV_NFAT | /* Advisory Non-Fatal */ + PCI_ERR_COR_INTERNAL | /* Corrected Internal */ + PCI_ERR_COR_LOG_OVER; /* Header Log Overflow */ + p_setd(perm, PCI_ERR_COR_STATUS, NO_VIRT, mask); + p_setd(perm, PCI_ERR_COR_MASK, NO_VIRT, mask); + + mask = PCI_ERR_CAP_ECRC_GENE | /* ECRC Generation Enable */ + PCI_ERR_CAP_ECRC_CHKE; /* ECRC Check Enable */ + p_setd(perm, PCI_ERR_CAP, NO_VIRT, mask); + return 0; +} + +/* Permissions for Power Budgeting extended capability */ +static int __init init_pci_ext_cap_pwr_perm(struct perm_bits *perm) +{ + if (alloc_perm_bits(perm, pci_ext_cap_length[PCI_EXT_CAP_ID_PWR])) + return -ENOMEM; + + p_setd(perm, 0, ALL_VIRT, NO_WRITE); + + /* Writing the data selector is OK, the info is still read-only */ + p_setb(perm, PCI_PWR_DATA, NO_VIRT, (u8)ALL_WRITE); + return 0; +} + +/* + * Initialize the shared permission tables + */ +void vfio_pci_uninit_perm_bits(void) +{ + free_perm_bits(&cap_perms[PCI_CAP_ID_BASIC]); + + free_perm_bits(&cap_perms[PCI_CAP_ID_PM]); + free_perm_bits(&cap_perms[PCI_CAP_ID_PCIX]); + free_perm_bits(&cap_perms[PCI_CAP_ID_EXP]); + free_perm_bits(&cap_perms[PCI_CAP_ID_AF]); + + free_perm_bits(&ecap_perms[PCI_EXT_CAP_ID_ERR]); + free_perm_bits(&ecap_perms[PCI_EXT_CAP_ID_PWR]); +} + +int __init vfio_pci_init_perm_bits(void) +{ + int ret; + + /* Basic config space */ + ret = init_pci_cap_basic_perm(&cap_perms[PCI_CAP_ID_BASIC]); + + /* Capabilities */ + ret |= init_pci_cap_pm_perm(&cap_perms[PCI_CAP_ID_PM]); + cap_perms[PCI_CAP_ID_VPD].writefn = vfio_direct_config_write; + ret |= init_pci_cap_pcix_perm(&cap_perms[PCI_CAP_ID_PCIX]); + cap_perms[PCI_CAP_ID_VNDR].writefn = vfio_direct_config_write; + ret |= init_pci_cap_exp_perm(&cap_perms[PCI_CAP_ID_EXP]); + ret |= init_pci_cap_af_perm(&cap_perms[PCI_CAP_ID_AF]); + + /* Extended capabilities */ + ret |= init_pci_ext_cap_err_perm(&ecap_perms[PCI_EXT_CAP_ID_ERR]); + ret |= init_pci_ext_cap_pwr_perm(&ecap_perms[PCI_EXT_CAP_ID_PWR]); + ecap_perms[PCI_EXT_CAP_ID_VNDR].writefn = vfio_direct_config_write; + + if (ret) + vfio_pci_uninit_perm_bits(); + + return ret; +} + +static int vfio_find_cap_start(struct vfio_pci_device *vdev, int pos) +{ + u8 cap; + int base = (pos >= PCI_CFG_SPACE_SIZE) ? PCI_CFG_SPACE_SIZE : + PCI_STD_HEADER_SIZEOF; + base /= 4; + pos /= 4; + + cap = vdev->pci_config_map[pos]; + + if (cap == PCI_CAP_ID_BASIC) + return 0; + + /* XXX Can we have to abutting capabilities of the same type? */ + while (pos - 1 >= base && vdev->pci_config_map[pos - 1] == cap) + pos--; + + return pos * 4; +} + +static int vfio_msi_config_read(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 *val) +{ + /* Update max available queue size from msi_qmax */ + if (offset <= PCI_MSI_FLAGS && offset + count >= PCI_MSI_FLAGS) { + __le16 *flags; + int start; + + start = vfio_find_cap_start(vdev, pos); + + flags = (__le16 *)&vdev->vconfig[start]; + + *flags &= cpu_to_le16(~PCI_MSI_FLAGS_QMASK); + *flags |= cpu_to_le16(vdev->msi_qmax << 1); + } + + return vfio_default_config_read(vdev, pos, count, perm, offset, val); +} + +static int vfio_msi_config_write(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 val) +{ + count = vfio_default_config_write(vdev, pos, count, perm, offset, val); + if (count < 0) + return count; + + /* Fixup and write configured queue size and enable to hardware */ + if (offset <= PCI_MSI_FLAGS && offset + count >= PCI_MSI_FLAGS) { + __le16 *pflags; + u16 flags; + int start, ret; + + start = vfio_find_cap_start(vdev, pos); + + pflags = (__le16 *)&vdev->vconfig[start + PCI_MSI_FLAGS]; + + flags = le16_to_cpu(*pflags); + + /* MSI is enabled via ioctl */ + if (!is_msi(vdev)) + flags &= ~PCI_MSI_FLAGS_ENABLE; + + /* Check queue size */ + if ((flags & PCI_MSI_FLAGS_QSIZE) >> 4 > vdev->msi_qmax) { + flags &= ~PCI_MSI_FLAGS_QSIZE; + flags |= vdev->msi_qmax << 4; + } + + /* Write back to virt and to hardware */ + *pflags = cpu_to_le16(flags); + ret = pci_user_write_config_word(vdev->pdev, + start + PCI_MSI_FLAGS, + flags); + if (ret) + return pcibios_err_to_errno(ret); + } + + return count; +} + +/* + * MSI determination is per-device, so this routine gets used beyond + * initialization time. Don't add __init + */ +static int init_pci_cap_msi_perm(struct perm_bits *perm, int len, u16 flags) +{ + if (alloc_perm_bits(perm, len)) + return -ENOMEM; + + perm->readfn = vfio_msi_config_read; + perm->writefn = vfio_msi_config_write; + + p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); + + /* + * The upper byte of the control register is reserved, + * just setup the lower byte. + */ + p_setb(perm, PCI_MSI_FLAGS, (u8)ALL_VIRT, (u8)ALL_WRITE); + p_setd(perm, PCI_MSI_ADDRESS_LO, ALL_VIRT, ALL_WRITE); + if (flags & PCI_MSI_FLAGS_64BIT) { + p_setd(perm, PCI_MSI_ADDRESS_HI, ALL_VIRT, ALL_WRITE); + p_setw(perm, PCI_MSI_DATA_64, (u16)ALL_VIRT, (u16)ALL_WRITE); + if (flags & PCI_MSI_FLAGS_MASKBIT) { + p_setd(perm, PCI_MSI_MASK_64, NO_VIRT, ALL_WRITE); + p_setd(perm, PCI_MSI_PENDING_64, NO_VIRT, ALL_WRITE); + } + } else { + p_setw(perm, PCI_MSI_DATA_32, (u16)ALL_VIRT, (u16)ALL_WRITE); + if (flags & PCI_MSI_FLAGS_MASKBIT) { + p_setd(perm, PCI_MSI_MASK_32, NO_VIRT, ALL_WRITE); + p_setd(perm, PCI_MSI_PENDING_32, NO_VIRT, ALL_WRITE); + } + } + return 0; +} + +/* Determine MSI CAP field length; initialize msi_perms on 1st call per vdev */ +static int vfio_msi_cap_len(struct vfio_pci_device *vdev, u8 pos) +{ + struct pci_dev *pdev = vdev->pdev; + int len, ret; + u16 flags; + + ret = pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &flags); + if (ret) + return pcibios_err_to_errno(ret); + + len = 10; /* Minimum size */ + if (flags & PCI_MSI_FLAGS_64BIT) + len += 4; + if (flags & PCI_MSI_FLAGS_MASKBIT) + len += 10; + + if (vdev->msi_perm) + return len; + + vdev->msi_perm = kmalloc(sizeof(struct perm_bits), GFP_KERNEL); + if (!vdev->msi_perm) + return -ENOMEM; + + ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags); + if (ret) + return ret; + + return len; +} + +/* Determine extended capability length for VC (2 & 9) and MFVC */ +static int vfio_vc_cap_len(struct vfio_pci_device *vdev, u16 pos) +{ + struct pci_dev *pdev = vdev->pdev; + u32 tmp; + int ret, evcc, phases, vc_arb; + int len = PCI_CAP_VC_BASE_SIZEOF; + + ret = pci_read_config_dword(pdev, pos + PCI_VC_PORT_REG1, &tmp); + if (ret) + return pcibios_err_to_errno(ret); + + evcc = tmp & PCI_VC_REG1_EVCC; /* extended vc count */ + ret = pci_read_config_dword(pdev, pos + PCI_VC_PORT_REG2, &tmp); + if (ret) + return pcibios_err_to_errno(ret); + + if (tmp & PCI_VC_REG2_128_PHASE) + phases = 128; + else if (tmp & PCI_VC_REG2_64_PHASE) + phases = 64; + else if (tmp & PCI_VC_REG2_32_PHASE) + phases = 32; + else + phases = 0; + + vc_arb = phases * 4; + + /* + * Port arbitration tables are root & switch only; + * function arbitration tables are function 0 only. + * In either case, we'll never let user write them so + * we don't care how big they are + */ + len += (1 + evcc) * PCI_CAP_VC_PER_VC_SIZEOF; + if (vc_arb) { + len = round_up(len, 16); + len += vc_arb / 8; + } + return len; +} + +static int vfio_cap_len(struct vfio_pci_device *vdev, u8 cap, u8 pos) +{ + struct pci_dev *pdev = vdev->pdev; + u16 word; + u8 byte; + int ret; + + switch (cap) { + case PCI_CAP_ID_MSI: + return vfio_msi_cap_len(vdev, pos); + case PCI_CAP_ID_PCIX: + ret = pci_read_config_word(pdev, pos + PCI_X_CMD, &word); + if (ret) + return pcibios_err_to_errno(ret); + + if (PCI_X_CMD_VERSION(word)) { + vdev->extended_caps = true; + return PCI_CAP_PCIX_SIZEOF_V2; + } else + return PCI_CAP_PCIX_SIZEOF_V0; + case PCI_CAP_ID_VNDR: + /* length follows next field */ + ret = pci_read_config_byte(pdev, pos + PCI_CAP_FLAGS, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + return byte; + case PCI_CAP_ID_EXP: + /* length based on version */ + ret = pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &word); + if (ret) + return pcibios_err_to_errno(ret); + + if ((word & PCI_EXP_FLAGS_VERS) == 1) + return PCI_CAP_EXP_ENDPOINT_SIZEOF_V1; + else { + vdev->extended_caps = true; + return PCI_CAP_EXP_ENDPOINT_SIZEOF_V2; + } + case PCI_CAP_ID_HT: + ret = pci_read_config_byte(pdev, pos + 3, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + return (byte & HT_3BIT_CAP_MASK) ? + HT_CAP_SIZEOF_SHORT : HT_CAP_SIZEOF_LONG; + case PCI_CAP_ID_SATA: + ret = pci_read_config_byte(pdev, pos + PCI_SATA_REGS, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + byte &= PCI_SATA_REGS_MASK; + if (byte == PCI_SATA_REGS_INLINE) + return PCI_SATA_SIZEOF_LONG; + else + return PCI_SATA_SIZEOF_SHORT; + default: + pr_warn("%s: %s unknown length for pci cap 0x%x@0x%x\n", + dev_name(&pdev->dev), __func__, cap, pos); + } + + return 0; +} + +static int vfio_ext_cap_len(struct vfio_pci_device *vdev, u16 ecap, u16 epos) +{ + struct pci_dev *pdev = vdev->pdev; + u8 byte; + u32 dword; + int ret; + + switch (ecap) { + case PCI_EXT_CAP_ID_VNDR: + ret = pci_read_config_dword(pdev, epos + PCI_VSEC_HDR, &dword); + if (ret) + return pcibios_err_to_errno(ret); + + return dword >> PCI_VSEC_HDR_LEN_SHIFT; + case PCI_EXT_CAP_ID_VC: + case PCI_EXT_CAP_ID_VC9: + case PCI_EXT_CAP_ID_MFVC: + return vfio_vc_cap_len(vdev, epos); + case PCI_EXT_CAP_ID_ACS: + ret = pci_read_config_byte(pdev, epos + PCI_ACS_CAP, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + if (byte & PCI_ACS_EC) { + int bits; + + ret = pci_read_config_byte(pdev, + epos + PCI_ACS_EGRESS_BITS, + &byte); + if (ret) + return pcibios_err_to_errno(ret); + + bits = byte ? round_up(byte, 32) : 256; + return 8 + (bits / 8); + } + return 8; + + case PCI_EXT_CAP_ID_REBAR: + ret = pci_read_config_byte(pdev, epos + PCI_REBAR_CTRL, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + byte &= PCI_REBAR_CTRL_NBAR_MASK; + byte >>= PCI_REBAR_CTRL_NBAR_SHIFT; + + return 4 + (byte * 8); + case PCI_EXT_CAP_ID_DPA: + ret = pci_read_config_byte(pdev, epos + PCI_DPA_CAP, &byte); + if (ret) + return pcibios_err_to_errno(ret); + + byte &= PCI_DPA_CAP_SUBSTATE_MASK; + byte = round_up(byte + 1, 4); + return PCI_DPA_BASE_SIZEOF + byte; + case PCI_EXT_CAP_ID_TPH: + ret = pci_read_config_dword(pdev, epos + PCI_TPH_CAP, &dword); + if (ret) + return pcibios_err_to_errno(ret); + + if ((dword & PCI_TPH_CAP_LOC_MASK) == PCI_TPH_LOC_CAP) { + int sts; + + sts = byte & PCI_TPH_CAP_ST_MASK; + sts >>= PCI_TPH_CAP_ST_SHIFT; + return PCI_TPH_BASE_SIZEOF + round_up(sts * 2, 4); + } + return PCI_TPH_BASE_SIZEOF; + default: + pr_warn("%s: %s unknown length for pci ecap 0x%x@0x%x\n", + dev_name(&pdev->dev), __func__, ecap, epos); + } + + return 0; +} + +static int vfio_fill_vconfig_bytes(struct vfio_pci_device *vdev, + int offset, int size) +{ + struct pci_dev *pdev = vdev->pdev; + int ret = 0; + + /* + * We try to read physical config space in the largest chunks + * we can, assuming that all of the fields support dword access. + * pci_save_state() makes this same assumption and seems to do ok. + */ + while (size) { + int filled; + + if (size >= 4 && !(offset % 4)) { + __le32 *dwordp = (__le32 *)&vdev->vconfig[offset]; + u32 dword; + + ret = pci_read_config_dword(pdev, offset, &dword); + if (ret) + return ret; + *dwordp = cpu_to_le32(dword); + filled = 4; + } else if (size >= 2 && !(offset % 2)) { + __le16 *wordp = (__le16 *)&vdev->vconfig[offset]; + u16 word; + + ret = pci_read_config_word(pdev, offset, &word); + if (ret) + return ret; + *wordp = cpu_to_le16(word); + filled = 2; + } else { + u8 *byte = &vdev->vconfig[offset]; + ret = pci_read_config_byte(pdev, offset, byte); + if (ret) + return ret; + filled = 1; + } + + offset += filled; + size -= filled; + } + + return ret; +} + +static int vfio_cap_init(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + u8 *map = vdev->pci_config_map; + u16 status; + u8 pos, *prev, cap; + int loops, ret, caps = 0; + + /* Any capabilities? */ + ret = pci_read_config_word(pdev, PCI_STATUS, &status); + if (ret) + return ret; + + if (!(status & PCI_STATUS_CAP_LIST)) + return 0; /* Done */ + + ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos); + if (ret) + return ret; + + /* Mark the previous position in case we want to skip a capability */ + prev = &vdev->vconfig[PCI_CAPABILITY_LIST]; + + /* We can bound our loop, capabilities are dword aligned */ + loops = (PCI_CFG_SPACE_SIZE - PCI_STD_HEADER_SIZEOF) / PCI_CAP_SIZEOF; + while (pos && loops--) { + u8 next; + int i, len = 0; + + ret = pci_read_config_byte(pdev, pos, &cap); + if (ret) + return ret; + + ret = pci_read_config_byte(pdev, + pos + PCI_CAP_LIST_NEXT, &next); + if (ret) + return ret; + + if (cap <= PCI_CAP_ID_MAX) { + len = pci_cap_length[cap]; + if (len == 0xFF) { /* Variable length */ + len = vfio_cap_len(vdev, cap, pos); + if (len < 0) + return len; + } + } + + if (!len) { + pr_info("%s: %s hiding cap 0x%x\n", + __func__, dev_name(&pdev->dev), cap); + *prev = next; + pos = next; + continue; + } + + /* Sanity check, do we overlap other capabilities? */ + for (i = 0; i < len; i += 4) { + if (likely(map[(pos + i) / 4] == PCI_CAP_ID_INVALID)) + continue; + + pr_warn("%s: %s pci config conflict @0x%x, was cap 0x%x now cap 0x%x\n", + __func__, dev_name(&pdev->dev), + pos + i, map[pos + i], cap); + } + + memset(map + (pos / 4), cap, len / 4); + ret = vfio_fill_vconfig_bytes(vdev, pos, len); + if (ret) + return ret; + + prev = &vdev->vconfig[pos + PCI_CAP_LIST_NEXT]; + pos = next; + caps++; + } + + /* If we didn't fill any capabilities, clear the status flag */ + if (!caps) { + __le16 *vstatus = (__le16 *)&vdev->vconfig[PCI_STATUS]; + *vstatus &= ~cpu_to_le16(PCI_STATUS_CAP_LIST); + } + + return 0; +} + +static int vfio_ecap_init(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + u8 *map = vdev->pci_config_map; + u16 epos; + __le32 *prev = NULL; + int loops, ret, ecaps = 0; + + if (!vdev->extended_caps) + return 0; + + epos = PCI_CFG_SPACE_SIZE; + + loops = (pdev->cfg_size - PCI_CFG_SPACE_SIZE) / PCI_CAP_SIZEOF; + + while (loops-- && epos >= PCI_CFG_SPACE_SIZE) { + u32 header; + u16 ecap; + int i, len = 0; + bool hidden = false; + + ret = pci_read_config_dword(pdev, epos, &header); + if (ret) + return ret; + + ecap = PCI_EXT_CAP_ID(header); + + if (ecap <= PCI_EXT_CAP_ID_MAX) { + len = pci_ext_cap_length[ecap]; + if (len == 0xFF) { + len = vfio_ext_cap_len(vdev, ecap, epos); + if (len < 0) + return ret; + } + } + + if (!len) { + pr_info("%s: %s hiding ecap 0x%x@0x%x\n", + __func__, dev_name(&pdev->dev), ecap, epos); + + /* If not the first in the chain, we can skip over it */ + if (prev) { + u32 val = epos = PCI_EXT_CAP_NEXT(header); + *prev &= cpu_to_le32(~(0xffcU << 20)); + *prev |= cpu_to_le32(val << 20); + continue; + } + + /* + * Otherwise, fill in a placeholder, the direct + * readfn will virtualize this automatically + */ + len = PCI_CAP_SIZEOF; + hidden = true; + } + + for (i = 0; i < len; i += 4) { + if (likely(map[(epos + i) / 4] == PCI_CAP_ID_INVALID)) + continue; + + pr_warn("%s: %s pci config conflict @0x%x, was ecap 0x%x now ecap 0x%x\n", + __func__, dev_name(&pdev->dev), + epos + i, map[epos + i], ecap); + } + + /* + * Even though ecap is 2 bytes, we're currently a long way + * from exceeding 1 byte capabilities. If we ever make it + * up to 0xFF we'll need to up this to a two-byte, byte map. + */ + BUILD_BUG_ON(PCI_EXT_CAP_ID_MAX >= PCI_CAP_ID_INVALID); + + memset(map + (epos / 4), ecap, len / 4); + ret = vfio_fill_vconfig_bytes(vdev, epos, len); + if (ret) + return ret; + + /* + * If we're just using this capability to anchor the list, + * hide the real ID. Only count real ecaps. XXX PCI spec + * indicates to use cap id = 0, version = 0, next = 0 if + * ecaps are absent, hope users check all the way to next. + */ + if (hidden) + *(__le32 *)&vdev->vconfig[epos] &= + cpu_to_le32((0xffcU << 20)); + else + ecaps++; + + prev = (__le32 *)&vdev->vconfig[epos]; + epos = PCI_EXT_CAP_NEXT(header); + } + + if (!ecaps) + *(u32 *)&vdev->vconfig[PCI_CFG_SPACE_SIZE] = 0; + + return 0; +} + +/* + * For each device we allocate a pci_config_map that indicates the + * capability occupying each dword and thus the struct perm_bits we + * use for read and write. We also allocate a virtualized config + * space which tracks reads and writes to bits that we emulate for + * the user. Initial values filled from device. + * + * Using shared stuct perm_bits between all vfio-pci devices saves + * us from allocating cfg_size buffers for virt and write for every + * device. We could remove vconfig and allocate individual buffers + * for each area requring emulated bits, but the array of pointers + * would be comparable in size (at least for standard config space). + */ +int vfio_config_init(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + u8 *map, *vconfig; + int ret; + + /* + * Config space, caps and ecaps are all dword aligned, so we can + * use one byte per dword to record the type. + */ + map = kmalloc(pdev->cfg_size / 4, GFP_KERNEL); + if (!map) + return -ENOMEM; + + vconfig = kmalloc(pdev->cfg_size, GFP_KERNEL); + if (!vconfig) { + kfree(map); + return -ENOMEM; + } + + vdev->pci_config_map = map; + vdev->vconfig = vconfig; + + memset(map, PCI_CAP_ID_BASIC, PCI_STD_HEADER_SIZEOF / 4); + memset(map + (PCI_STD_HEADER_SIZEOF / 4), PCI_CAP_ID_INVALID, + (pdev->cfg_size - PCI_STD_HEADER_SIZEOF) / 4); + + ret = vfio_fill_vconfig_bytes(vdev, 0, PCI_STD_HEADER_SIZEOF); + if (ret) + goto out; + + vdev->bardirty = true; + + /* + * XXX can we just pci_load_saved_state/pci_restore_state? + * may need to rebuild vconfig after that + */ + + /* For restore after reset */ + vdev->rbar[0] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_0]); + vdev->rbar[1] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_1]); + vdev->rbar[2] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_2]); + vdev->rbar[3] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_3]); + vdev->rbar[4] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_4]); + vdev->rbar[5] = le32_to_cpu(*(__le32 *)&vconfig[PCI_BASE_ADDRESS_5]); + vdev->rbar[6] = le32_to_cpu(*(__le32 *)&vconfig[PCI_ROM_ADDRESS]); + + if (pdev->is_virtfn) { + *(__le16 *)&vconfig[PCI_VENDOR_ID] = cpu_to_le16(pdev->vendor); + *(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device); + } + + ret = vfio_cap_init(vdev); + if (ret) + goto out; + + ret = vfio_ecap_init(vdev); + if (ret) + goto out; + + return 0; + +out: + kfree(map); + vdev->pci_config_map = NULL; + kfree(vconfig); + vdev->vconfig = NULL; + return pcibios_err_to_errno(ret); +} + +void vfio_config_free(struct vfio_pci_device *vdev) +{ + kfree(vdev->vconfig); + vdev->vconfig = NULL; + kfree(vdev->pci_config_map); + vdev->pci_config_map = NULL; + kfree(vdev->msi_perm); + vdev->msi_perm = NULL; +} + +static ssize_t vfio_config_do_rw(struct vfio_pci_device *vdev, char __user *buf, + size_t count, loff_t *ppos, bool iswrite) +{ + struct pci_dev *pdev = vdev->pdev; + struct perm_bits *perm; + __le32 val = 0; + int cap_start = 0, offset; + u8 cap_id; + ssize_t ret = count; + + if (*ppos < 0 || *ppos + count > pdev->cfg_size) + return -EFAULT; + + /* + * gcc can't seem to figure out we're a static function, only called + * with count of 1/2/4 and hits copy_from_user_overflow without this. + */ + if (count > sizeof(val)) + return -EINVAL; + + cap_id = vdev->pci_config_map[*ppos / 4]; + + if (cap_id == PCI_CAP_ID_INVALID) { + if (iswrite) + return ret; /* drop */ + + /* + * Per PCI spec 3.0, section 6.1, reads from reserved and + * unimplemented registers return 0 + */ + if (copy_to_user(buf, &val, count)) + return -EFAULT; + + return ret; + } + + /* + * All capabilities are minimum 4 bytes and aligned on dword + * boundaries. Since we don't support unaligned accesses, we're + * only ever accessing a single capability. + */ + if (*ppos >= PCI_CFG_SPACE_SIZE) { + WARN_ON(cap_id > PCI_EXT_CAP_ID_MAX); + + perm = &ecap_perms[cap_id]; + cap_start = vfio_find_cap_start(vdev, *ppos); + + } else { + WARN_ON(cap_id > PCI_CAP_ID_MAX); + + perm = &cap_perms[cap_id]; + + if (cap_id == PCI_CAP_ID_MSI) + perm = vdev->msi_perm; + + if (cap_id > PCI_CAP_ID_BASIC) + cap_start = vfio_find_cap_start(vdev, *ppos); + } + + WARN_ON(!cap_start && cap_id != PCI_CAP_ID_BASIC); + WARN_ON(cap_start > *ppos); + + offset = *ppos - cap_start; + + if (iswrite) { + if (!perm->writefn) + return ret; + + if (copy_from_user(&val, buf, count)) + return -EFAULT; + + ret = perm->writefn(vdev, *ppos, count, perm, offset, val); + } else { + if (perm->readfn) { + ret = perm->readfn(vdev, *ppos, count, + perm, offset, &val); + if (ret < 0) + return ret; + } + + if (copy_to_user(buf, &val, count)) + return -EFAULT; + } + + return ret; +} + +ssize_t vfio_pci_config_readwrite(struct vfio_pci_device *vdev, + char __user *buf, size_t count, + loff_t *ppos, bool iswrite) +{ + size_t done = 0; + int ret = 0; + loff_t pos = *ppos; + + pos &= VFIO_PCI_OFFSET_MASK; + + /* + * We want to both keep the access size the caller users as well as + * support reading large chunks of config space in a single call. + * PCI doesn't support unaligned accesses, so we can safely break + * those apart. + */ + while (count) { + if (count >= 4 && !(pos % 4)) + ret = vfio_config_do_rw(vdev, buf, 4, &pos, iswrite); + else if (count >= 2 && !(pos % 2)) + ret = vfio_config_do_rw(vdev, buf, 2, &pos, iswrite); + else + ret = vfio_config_do_rw(vdev, buf, 1, &pos, iswrite); + + if (ret < 0) + return ret; + + count -= ret; + done += ret; + buf += ret; + pos += ret; + } + + *ppos += done; + + return done; +} diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c new file mode 100644 index 000000000000..211a4920b88a --- /dev/null +++ b/drivers/vfio/pci/vfio_pci_intrs.c @@ -0,0 +1,740 @@ +/* + * VFIO PCI interrupt handling + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + */ + +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/eventfd.h> +#include <linux/pci.h> +#include <linux/file.h> +#include <linux/poll.h> +#include <linux/vfio.h> +#include <linux/wait.h> +#include <linux/workqueue.h> + +#include "vfio_pci_private.h" + +/* + * IRQfd - generic + */ +struct virqfd { + struct vfio_pci_device *vdev; + struct eventfd_ctx *eventfd; + int (*handler)(struct vfio_pci_device *, void *); + void (*thread)(struct vfio_pci_device *, void *); + void *data; + struct work_struct inject; + wait_queue_t wait; + poll_table pt; + struct work_struct shutdown; + struct virqfd **pvirqfd; +}; + +static struct workqueue_struct *vfio_irqfd_cleanup_wq; + +int __init vfio_pci_virqfd_init(void) +{ + vfio_irqfd_cleanup_wq = + create_singlethread_workqueue("vfio-irqfd-cleanup"); + if (!vfio_irqfd_cleanup_wq) + return -ENOMEM; + + return 0; +} + +void vfio_pci_virqfd_exit(void) +{ + destroy_workqueue(vfio_irqfd_cleanup_wq); +} + +static void virqfd_deactivate(struct virqfd *virqfd) +{ + queue_work(vfio_irqfd_cleanup_wq, &virqfd->shutdown); +} + +static int virqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key) +{ + struct virqfd *virqfd = container_of(wait, struct virqfd, wait); + unsigned long flags = (unsigned long)key; + + if (flags & POLLIN) { + /* An event has been signaled, call function */ + if ((!virqfd->handler || + virqfd->handler(virqfd->vdev, virqfd->data)) && + virqfd->thread) + schedule_work(&virqfd->inject); + } + + if (flags & POLLHUP) + /* The eventfd is closing, detach from VFIO */ + virqfd_deactivate(virqfd); + + return 0; +} + +static void virqfd_ptable_queue_proc(struct file *file, + wait_queue_head_t *wqh, poll_table *pt) +{ + struct virqfd *virqfd = container_of(pt, struct virqfd, pt); + add_wait_queue(wqh, &virqfd->wait); +} + +static void virqfd_shutdown(struct work_struct *work) +{ + struct virqfd *virqfd = container_of(work, struct virqfd, shutdown); + struct virqfd **pvirqfd = virqfd->pvirqfd; + u64 cnt; + + eventfd_ctx_remove_wait_queue(virqfd->eventfd, &virqfd->wait, &cnt); + flush_work(&virqfd->inject); + eventfd_ctx_put(virqfd->eventfd); + + kfree(virqfd); + *pvirqfd = NULL; +} + +static void virqfd_inject(struct work_struct *work) +{ + struct virqfd *virqfd = container_of(work, struct virqfd, inject); + if (virqfd->thread) + virqfd->thread(virqfd->vdev, virqfd->data); +} + +static int virqfd_enable(struct vfio_pci_device *vdev, + int (*handler)(struct vfio_pci_device *, void *), + void (*thread)(struct vfio_pci_device *, void *), + void *data, struct virqfd **pvirqfd, int fd) +{ + struct file *file = NULL; + struct eventfd_ctx *ctx = NULL; + struct virqfd *virqfd; + int ret = 0; + unsigned int events; + + if (*pvirqfd) + return -EBUSY; + + virqfd = kzalloc(sizeof(*virqfd), GFP_KERNEL); + if (!virqfd) + return -ENOMEM; + + virqfd->pvirqfd = pvirqfd; + *pvirqfd = virqfd; + virqfd->vdev = vdev; + virqfd->handler = handler; + virqfd->thread = thread; + virqfd->data = data; + + INIT_WORK(&virqfd->shutdown, virqfd_shutdown); + INIT_WORK(&virqfd->inject, virqfd_inject); + + file = eventfd_fget(fd); + if (IS_ERR(file)) { + ret = PTR_ERR(file); + goto fail; + } + + ctx = eventfd_ctx_fileget(file); + if (IS_ERR(ctx)) { + ret = PTR_ERR(ctx); + goto fail; + } + + virqfd->eventfd = ctx; + + /* + * Install our own custom wake-up handling so we are notified via + * a callback whenever someone signals the underlying eventfd. + */ + init_waitqueue_func_entry(&virqfd->wait, virqfd_wakeup); + init_poll_funcptr(&virqfd->pt, virqfd_ptable_queue_proc); + + events = file->f_op->poll(file, &virqfd->pt); + + /* + * Check if there was an event already pending on the eventfd + * before we registered and trigger it as if we didn't miss it. + */ + if (events & POLLIN) { + if ((!handler || handler(vdev, data)) && thread) + schedule_work(&virqfd->inject); + } + + /* + * Do not drop the file until the irqfd is fully initialized, + * otherwise we might race against the POLLHUP. + */ + fput(file); + + return 0; + +fail: + if (ctx && !IS_ERR(ctx)) + eventfd_ctx_put(ctx); + + if (file && !IS_ERR(file)) + fput(file); + + kfree(virqfd); + *pvirqfd = NULL; + + return ret; +} + +static void virqfd_disable(struct virqfd *virqfd) +{ + if (!virqfd) + return; + + virqfd_deactivate(virqfd); + + /* Block until we know all outstanding shutdown jobs have completed. */ + flush_workqueue(vfio_irqfd_cleanup_wq); +} + +/* + * INTx + */ +static void vfio_send_intx_eventfd(struct vfio_pci_device *vdev, void *unused) +{ + if (likely(is_intx(vdev) && !vdev->virq_disabled)) + eventfd_signal(vdev->ctx[0].trigger, 1); +} + +void vfio_pci_intx_mask(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + unsigned long flags; + + spin_lock_irqsave(&vdev->irqlock, flags); + + /* + * Masking can come from interrupt, ioctl, or config space + * via INTx disable. The latter means this can get called + * even when not using intx delivery. In this case, just + * try to have the physical bit follow the virtual bit. + */ + if (unlikely(!is_intx(vdev))) { + if (vdev->pci_2_3) + pci_intx(pdev, 0); + } else if (!vdev->ctx[0].masked) { + /* + * Can't use check_and_mask here because we always want to + * mask, not just when something is pending. + */ + if (vdev->pci_2_3) + pci_intx(pdev, 0); + else + disable_irq_nosync(pdev->irq); + + vdev->ctx[0].masked = true; + } + + spin_unlock_irqrestore(&vdev->irqlock, flags); +} + +/* + * If this is triggered by an eventfd, we can't call eventfd_signal + * or else we'll deadlock on the eventfd wait queue. Return >0 when + * a signal is necessary, which can then be handled via a work queue + * or directly depending on the caller. + */ +int vfio_pci_intx_unmask_handler(struct vfio_pci_device *vdev, void *unused) +{ + struct pci_dev *pdev = vdev->pdev; + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&vdev->irqlock, flags); + + /* + * Unmasking comes from ioctl or config, so again, have the + * physical bit follow the virtual even when not using INTx. + */ + if (unlikely(!is_intx(vdev))) { + if (vdev->pci_2_3) + pci_intx(pdev, 1); + } else if (vdev->ctx[0].masked && !vdev->virq_disabled) { + /* + * A pending interrupt here would immediately trigger, + * but we can avoid that overhead by just re-sending + * the interrupt to the user. + */ + if (vdev->pci_2_3) { + if (!pci_check_and_unmask_intx(pdev)) + ret = 1; + } else + enable_irq(pdev->irq); + + vdev->ctx[0].masked = (ret > 0); + } + + spin_unlock_irqrestore(&vdev->irqlock, flags); + + return ret; +} + +void vfio_pci_intx_unmask(struct vfio_pci_device *vdev) +{ + if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0) + vfio_send_intx_eventfd(vdev, NULL); +} + +static irqreturn_t vfio_intx_handler(int irq, void *dev_id) +{ + struct vfio_pci_device *vdev = dev_id; + unsigned long flags; + int ret = IRQ_NONE; + + spin_lock_irqsave(&vdev->irqlock, flags); + + if (!vdev->pci_2_3) { + disable_irq_nosync(vdev->pdev->irq); + vdev->ctx[0].masked = true; + ret = IRQ_HANDLED; + } else if (!vdev->ctx[0].masked && /* may be shared */ + pci_check_and_mask_intx(vdev->pdev)) { + vdev->ctx[0].masked = true; + ret = IRQ_HANDLED; + } + + spin_unlock_irqrestore(&vdev->irqlock, flags); + + if (ret == IRQ_HANDLED) + vfio_send_intx_eventfd(vdev, NULL); + + return ret; +} + +static int vfio_intx_enable(struct vfio_pci_device *vdev) +{ + if (!is_irq_none(vdev)) + return -EINVAL; + + if (!vdev->pdev->irq) + return -ENODEV; + + vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL); + if (!vdev->ctx) + return -ENOMEM; + + vdev->num_ctx = 1; + vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX; + + return 0; +} + +static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd) +{ + struct pci_dev *pdev = vdev->pdev; + unsigned long irqflags = IRQF_SHARED; + struct eventfd_ctx *trigger; + unsigned long flags; + int ret; + + if (vdev->ctx[0].trigger) { + free_irq(pdev->irq, vdev); + kfree(vdev->ctx[0].name); + eventfd_ctx_put(vdev->ctx[0].trigger); + vdev->ctx[0].trigger = NULL; + } + + if (fd < 0) /* Disable only */ + return 0; + + vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)", + pci_name(pdev)); + if (!vdev->ctx[0].name) + return -ENOMEM; + + trigger = eventfd_ctx_fdget(fd); + if (IS_ERR(trigger)) { + kfree(vdev->ctx[0].name); + return PTR_ERR(trigger); + } + + if (!vdev->pci_2_3) + irqflags = 0; + + ret = request_irq(pdev->irq, vfio_intx_handler, + irqflags, vdev->ctx[0].name, vdev); + if (ret) { + kfree(vdev->ctx[0].name); + eventfd_ctx_put(trigger); + return ret; + } + + vdev->ctx[0].trigger = trigger; + + /* + * INTx disable will stick across the new irq setup, + * disable_irq won't. + */ + spin_lock_irqsave(&vdev->irqlock, flags); + if (!vdev->pci_2_3 && (vdev->ctx[0].masked || vdev->virq_disabled)) + disable_irq_nosync(pdev->irq); + spin_unlock_irqrestore(&vdev->irqlock, flags); + + return 0; +} + +static void vfio_intx_disable(struct vfio_pci_device *vdev) +{ + vfio_intx_set_signal(vdev, -1); + virqfd_disable(vdev->ctx[0].unmask); + virqfd_disable(vdev->ctx[0].mask); + vdev->irq_type = VFIO_PCI_NUM_IRQS; + vdev->num_ctx = 0; + kfree(vdev->ctx); +} + +/* + * MSI/MSI-X + */ +static irqreturn_t vfio_msihandler(int irq, void *arg) +{ + struct eventfd_ctx *trigger = arg; + + eventfd_signal(trigger, 1); + return IRQ_HANDLED; +} + +static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix) +{ + struct pci_dev *pdev = vdev->pdev; + int ret; + + if (!is_irq_none(vdev)) + return -EINVAL; + + vdev->ctx = kzalloc(nvec * sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL); + if (!vdev->ctx) + return -ENOMEM; + + if (msix) { + int i; + + vdev->msix = kzalloc(nvec * sizeof(struct msix_entry), + GFP_KERNEL); + if (!vdev->msix) { + kfree(vdev->ctx); + return -ENOMEM; + } + + for (i = 0; i < nvec; i++) + vdev->msix[i].entry = i; + + ret = pci_enable_msix(pdev, vdev->msix, nvec); + if (ret) { + kfree(vdev->msix); + kfree(vdev->ctx); + return ret; + } + } else { + ret = pci_enable_msi_block(pdev, nvec); + if (ret) { + kfree(vdev->ctx); + return ret; + } + } + + vdev->num_ctx = nvec; + vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX : + VFIO_PCI_MSI_IRQ_INDEX; + + if (!msix) { + /* + * Compute the virtual hardware field for max msi vectors - + * it is the log base 2 of the number of vectors. + */ + vdev->msi_qmax = fls(nvec * 2 - 1) - 1; + } + + return 0; +} + +static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev, + int vector, int fd, bool msix) +{ + struct pci_dev *pdev = vdev->pdev; + int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector; + char *name = msix ? "vfio-msix" : "vfio-msi"; + struct eventfd_ctx *trigger; + int ret; + + if (vector >= vdev->num_ctx) + return -EINVAL; + + if (vdev->ctx[vector].trigger) { + free_irq(irq, vdev->ctx[vector].trigger); + kfree(vdev->ctx[vector].name); + eventfd_ctx_put(vdev->ctx[vector].trigger); + vdev->ctx[vector].trigger = NULL; + } + + if (fd < 0) + return 0; + + vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "%s[%d](%s)", + name, vector, pci_name(pdev)); + if (!vdev->ctx[vector].name) + return -ENOMEM; + + trigger = eventfd_ctx_fdget(fd); + if (IS_ERR(trigger)) { + kfree(vdev->ctx[vector].name); + return PTR_ERR(trigger); + } + + ret = request_irq(irq, vfio_msihandler, 0, + vdev->ctx[vector].name, trigger); + if (ret) { + kfree(vdev->ctx[vector].name); + eventfd_ctx_put(trigger); + return ret; + } + + vdev->ctx[vector].trigger = trigger; + + return 0; +} + +static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start, + unsigned count, int32_t *fds, bool msix) +{ + int i, j, ret = 0; + + if (start + count > vdev->num_ctx) + return -EINVAL; + + for (i = 0, j = start; i < count && !ret; i++, j++) { + int fd = fds ? fds[i] : -1; + ret = vfio_msi_set_vector_signal(vdev, j, fd, msix); + } + + if (ret) { + for (--j; j >= start; j--) + vfio_msi_set_vector_signal(vdev, j, -1, msix); + } + + return ret; +} + +static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix) +{ + struct pci_dev *pdev = vdev->pdev; + int i; + + vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix); + + for (i = 0; i < vdev->num_ctx; i++) { + virqfd_disable(vdev->ctx[i].unmask); + virqfd_disable(vdev->ctx[i].mask); + } + + if (msix) { + pci_disable_msix(vdev->pdev); + kfree(vdev->msix); + } else + pci_disable_msi(pdev); + + vdev->irq_type = VFIO_PCI_NUM_IRQS; + vdev->num_ctx = 0; + kfree(vdev->ctx); +} + +/* + * IOCTL support + */ +static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev, + unsigned index, unsigned start, + unsigned count, uint32_t flags, void *data) +{ + if (!is_intx(vdev) || start != 0 || count != 1) + return -EINVAL; + + if (flags & VFIO_IRQ_SET_DATA_NONE) { + vfio_pci_intx_unmask(vdev); + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { + uint8_t unmask = *(uint8_t *)data; + if (unmask) + vfio_pci_intx_unmask(vdev); + } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) { + int32_t fd = *(int32_t *)data; + if (fd >= 0) + return virqfd_enable(vdev, vfio_pci_intx_unmask_handler, + vfio_send_intx_eventfd, NULL, + &vdev->ctx[0].unmask, fd); + + virqfd_disable(vdev->ctx[0].unmask); + } + + return 0; +} + +static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev, + unsigned index, unsigned start, + unsigned count, uint32_t flags, void *data) +{ + if (!is_intx(vdev) || start != 0 || count != 1) + return -EINVAL; + + if (flags & VFIO_IRQ_SET_DATA_NONE) { + vfio_pci_intx_mask(vdev); + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { + uint8_t mask = *(uint8_t *)data; + if (mask) + vfio_pci_intx_mask(vdev); + } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) { + return -ENOTTY; /* XXX implement me */ + } + + return 0; +} + +static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev, + unsigned index, unsigned start, + unsigned count, uint32_t flags, void *data) +{ + if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) { + vfio_intx_disable(vdev); + return 0; + } + + if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1) + return -EINVAL; + + if (flags & VFIO_IRQ_SET_DATA_EVENTFD) { + int32_t fd = *(int32_t *)data; + int ret; + + if (is_intx(vdev)) + return vfio_intx_set_signal(vdev, fd); + + ret = vfio_intx_enable(vdev); + if (ret) + return ret; + + ret = vfio_intx_set_signal(vdev, fd); + if (ret) + vfio_intx_disable(vdev); + + return ret; + } + + if (!is_intx(vdev)) + return -EINVAL; + + if (flags & VFIO_IRQ_SET_DATA_NONE) { + vfio_send_intx_eventfd(vdev, NULL); + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { + uint8_t trigger = *(uint8_t *)data; + if (trigger) + vfio_send_intx_eventfd(vdev, NULL); + } + return 0; +} + +static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev, + unsigned index, unsigned start, + unsigned count, uint32_t flags, void *data) +{ + int i; + bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false; + + if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) { + vfio_msi_disable(vdev, msix); + return 0; + } + + if (!(irq_is(vdev, index) || is_irq_none(vdev))) + return -EINVAL; + + if (flags & VFIO_IRQ_SET_DATA_EVENTFD) { + int32_t *fds = data; + int ret; + + if (vdev->irq_type == index) + return vfio_msi_set_block(vdev, start, count, + fds, msix); + + ret = vfio_msi_enable(vdev, start + count, msix); + if (ret) + return ret; + + ret = vfio_msi_set_block(vdev, start, count, fds, msix); + if (ret) + vfio_msi_disable(vdev, msix); + + return ret; + } + + if (!irq_is(vdev, index) || start + count > vdev->num_ctx) + return -EINVAL; + + for (i = start; i < start + count; i++) { + if (!vdev->ctx[i].trigger) + continue; + if (flags & VFIO_IRQ_SET_DATA_NONE) { + eventfd_signal(vdev->ctx[i].trigger, 1); + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { + uint8_t *bools = data; + if (bools[i - start]) + eventfd_signal(vdev->ctx[i].trigger, 1); + } + } + return 0; +} + +int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags, + unsigned index, unsigned start, unsigned count, + void *data) +{ + int (*func)(struct vfio_pci_device *vdev, unsigned index, + unsigned start, unsigned count, uint32_t flags, + void *data) = NULL; + + switch (index) { + case VFIO_PCI_INTX_IRQ_INDEX: + switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) { + case VFIO_IRQ_SET_ACTION_MASK: + func = vfio_pci_set_intx_mask; + break; + case VFIO_IRQ_SET_ACTION_UNMASK: + func = vfio_pci_set_intx_unmask; + break; + case VFIO_IRQ_SET_ACTION_TRIGGER: + func = vfio_pci_set_intx_trigger; + break; + } + break; + case VFIO_PCI_MSI_IRQ_INDEX: + case VFIO_PCI_MSIX_IRQ_INDEX: + switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) { + case VFIO_IRQ_SET_ACTION_MASK: + case VFIO_IRQ_SET_ACTION_UNMASK: + /* XXX Need masking support exported */ + break; + case VFIO_IRQ_SET_ACTION_TRIGGER: + func = vfio_pci_set_msi_trigger; + break; + } + break; + } + + if (!func) + return -ENOTTY; + + return func(vdev, index, start, count, flags, data); +} diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h new file mode 100644 index 000000000000..611827cba8cd --- /dev/null +++ b/drivers/vfio/pci/vfio_pci_private.h @@ -0,0 +1,91 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * 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> + +#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) + +struct vfio_pci_irq_ctx { + struct eventfd_ctx *trigger; + struct virqfd *unmask; + struct virqfd *mask; + char *name; + bool masked; +}; + +struct vfio_pci_device { + struct pci_dev *pdev; + void __iomem *barmap[PCI_STD_RESOURCE_END + 1]; + u8 *pci_config_map; + u8 *vconfig; + struct perm_bits *msi_perm; + spinlock_t irqlock; + struct mutex igate; + struct msix_entry *msix; + struct vfio_pci_irq_ctx *ctx; + int num_ctx; + int irq_type; + 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; + struct pci_saved_state *pci_saved_state; + atomic_t refcnt; +}; + +#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_readwrite(struct vfio_pci_device *vdev, + char __user *buf, size_t count, + loff_t *ppos, bool iswrite); +extern ssize_t vfio_pci_mem_readwrite(struct vfio_pci_device *vdev, + char __user *buf, size_t count, + loff_t *ppos, bool iswrite); +extern ssize_t vfio_pci_io_readwrite(struct vfio_pci_device *vdev, + char __user *buf, size_t count, + loff_t *ppos, bool iswrite); + +extern int vfio_pci_init_perm_bits(void); +extern void vfio_pci_uninit_perm_bits(void); + +extern int vfio_pci_virqfd_init(void); +extern void vfio_pci_virqfd_exit(void); + +extern int vfio_config_init(struct vfio_pci_device *vdev); +extern void vfio_config_free(struct vfio_pci_device *vdev); +#endif /* VFIO_PCI_PRIVATE_H */ diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c new file mode 100644 index 000000000000..4362d9e7baa3 --- /dev/null +++ b/drivers/vfio/pci/vfio_pci_rdwr.c @@ -0,0 +1,269 @@ +/* + * VFIO PCI I/O Port & MMIO access + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + */ + +#include <linux/fs.h> +#include <linux/pci.h> +#include <linux/uaccess.h> +#include <linux/io.h> + +#include "vfio_pci_private.h" + +/* I/O Port BAR access */ +ssize_t vfio_pci_io_readwrite(struct vfio_pci_device *vdev, char __user *buf, + size_t count, loff_t *ppos, bool iswrite) +{ + struct pci_dev *pdev = vdev->pdev; + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + int bar = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + void __iomem *io; + size_t done = 0; + + if (!pci_resource_start(pdev, bar)) + return -EINVAL; + + if (pos + count > pci_resource_len(pdev, bar)) + return -EINVAL; + + if (!vdev->barmap[bar]) { + int ret; + + ret = pci_request_selected_regions(pdev, 1 << bar, "vfio"); + if (ret) + return ret; + + vdev->barmap[bar] = pci_iomap(pdev, bar, 0); + + if (!vdev->barmap[bar]) { + pci_release_selected_regions(pdev, 1 << bar); + return -EINVAL; + } + } + + io = vdev->barmap[bar]; + + while (count) { + int filled; + + if (count >= 3 && !(pos % 4)) { + __le32 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 4)) + return -EFAULT; + + iowrite32(le32_to_cpu(val), io + pos); + } else { + val = cpu_to_le32(ioread32(io + pos)); + + if (copy_to_user(buf, &val, 4)) + return -EFAULT; + } + + filled = 4; + + } else if ((pos % 2) == 0 && count >= 2) { + __le16 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 2)) + return -EFAULT; + + iowrite16(le16_to_cpu(val), io + pos); + } else { + val = cpu_to_le16(ioread16(io + pos)); + + if (copy_to_user(buf, &val, 2)) + return -EFAULT; + } + + filled = 2; + } else { + u8 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 1)) + return -EFAULT; + + iowrite8(val, io + pos); + } else { + val = ioread8(io + pos); + + if (copy_to_user(buf, &val, 1)) + return -EFAULT; + } + + filled = 1; + } + + count -= filled; + done += filled; + buf += filled; + pos += filled; + } + + *ppos += done; + + return done; +} + +/* + * MMIO BAR access + * We handle two excluded ranges here as well, if the user tries to read + * the ROM beyond what PCI tells us is available or the MSI-X table region, + * we return 0xFF and writes are dropped. + */ +ssize_t vfio_pci_mem_readwrite(struct vfio_pci_device *vdev, char __user *buf, + size_t count, loff_t *ppos, bool iswrite) +{ + struct pci_dev *pdev = vdev->pdev; + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + int bar = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + void __iomem *io; + resource_size_t end; + size_t done = 0; + size_t x_start = 0, x_end = 0; /* excluded range */ + + if (!pci_resource_start(pdev, bar)) + return -EINVAL; + + end = pci_resource_len(pdev, bar); + + if (pos > end) + return -EINVAL; + + if (pos == end) + return 0; + + if (pos + count > end) + count = end - pos; + + if (bar == PCI_ROM_RESOURCE) { + io = pci_map_rom(pdev, &x_start); + x_end = end; + } else { + if (!vdev->barmap[bar]) { + int ret; + + ret = pci_request_selected_regions(pdev, 1 << bar, + "vfio"); + if (ret) + return ret; + + vdev->barmap[bar] = pci_iomap(pdev, bar, 0); + + if (!vdev->barmap[bar]) { + pci_release_selected_regions(pdev, 1 << bar); + return -EINVAL; + } + } + + io = vdev->barmap[bar]; + + if (bar == vdev->msix_bar) { + x_start = vdev->msix_offset; + x_end = vdev->msix_offset + vdev->msix_size; + } + } + + if (!io) + return -EINVAL; + + while (count) { + size_t fillable, filled; + + if (pos < x_start) + fillable = x_start - pos; + else if (pos >= x_end) + fillable = end - pos; + else + fillable = 0; + + if (fillable >= 4 && !(pos % 4) && (count >= 4)) { + __le32 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 4)) + goto out; + + iowrite32(le32_to_cpu(val), io + pos); + } else { + val = cpu_to_le32(ioread32(io + pos)); + + if (copy_to_user(buf, &val, 4)) + goto out; + } + + filled = 4; + } else if (fillable >= 2 && !(pos % 2) && (count >= 2)) { + __le16 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 2)) + goto out; + + iowrite16(le16_to_cpu(val), io + pos); + } else { + val = cpu_to_le16(ioread16(io + pos)); + + if (copy_to_user(buf, &val, 2)) + goto out; + } + + filled = 2; + } else if (fillable) { + u8 val; + + if (iswrite) { + if (copy_from_user(&val, buf, 1)) + goto out; + + iowrite8(val, io + pos); + } else { + val = ioread8(io + pos); + + if (copy_to_user(buf, &val, 1)) + goto out; + } + + filled = 1; + } else { + /* Drop writes, fill reads with FF */ + if (!iswrite) { + char val = 0xFF; + size_t i; + + for (i = 0; i < x_end - pos; i++) { + if (put_user(val, buf + i)) + goto out; + } + } + + filled = x_end - pos; + } + + count -= filled; + done += filled; + buf += filled; + pos += filled; + } + + *ppos += done; + +out: + if (bar == PCI_ROM_RESOURCE) + pci_unmap_rom(pdev, io); + + return count ? -EFAULT : done; +} diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c new file mode 100644 index 000000000000..9591e2b509d7 --- /dev/null +++ b/drivers/vfio/vfio.c @@ -0,0 +1,1420 @@ +/* + * VFIO core + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + */ + +#include <linux/cdev.h> +#include <linux/compat.h> +#include <linux/device.h> +#include <linux/file.h> +#include <linux/anon_inodes.h> +#include <linux/fs.h> +#include <linux/idr.h> +#include <linux/iommu.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/uaccess.h> +#include <linux/vfio.h> +#include <linux/wait.h> + +#define DRIVER_VERSION "0.3" +#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" +#define DRIVER_DESC "VFIO - User Level meta-driver" + +static struct vfio { + struct class *class; + struct list_head iommu_drivers_list; + struct mutex iommu_drivers_lock; + struct list_head group_list; + struct idr group_idr; + struct mutex group_lock; + struct cdev group_cdev; + struct device *dev; + dev_t devt; + struct cdev cdev; + wait_queue_head_t release_q; +} vfio; + +struct vfio_iommu_driver { + const struct vfio_iommu_driver_ops *ops; + struct list_head vfio_next; +}; + +struct vfio_container { + struct kref kref; + struct list_head group_list; + struct mutex group_lock; + struct vfio_iommu_driver *iommu_driver; + void *iommu_data; +}; + +struct vfio_group { + struct kref kref; + int minor; + atomic_t container_users; + struct iommu_group *iommu_group; + struct vfio_container *container; + struct list_head device_list; + struct mutex device_lock; + struct device *dev; + struct notifier_block nb; + struct list_head vfio_next; + struct list_head container_next; +}; + +struct vfio_device { + struct kref kref; + struct device *dev; + const struct vfio_device_ops *ops; + struct vfio_group *group; + struct list_head group_next; + void *device_data; +}; + +/** + * IOMMU driver registration + */ +int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops) +{ + struct vfio_iommu_driver *driver, *tmp; + + driver = kzalloc(sizeof(*driver), GFP_KERNEL); + if (!driver) + return -ENOMEM; + + driver->ops = ops; + + mutex_lock(&vfio.iommu_drivers_lock); + + /* Check for duplicates */ + list_for_each_entry(tmp, &vfio.iommu_drivers_list, vfio_next) { + if (tmp->ops == ops) { + mutex_unlock(&vfio.iommu_drivers_lock); + kfree(driver); + return -EINVAL; + } + } + + list_add(&driver->vfio_next, &vfio.iommu_drivers_list); + + mutex_unlock(&vfio.iommu_drivers_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(vfio_register_iommu_driver); + +void vfio_unregister_iommu_driver(const struct vfio_iommu_driver_ops *ops) +{ + struct vfio_iommu_driver *driver; + + mutex_lock(&vfio.iommu_drivers_lock); + list_for_each_entry(driver, &vfio.iommu_drivers_list, vfio_next) { + if (driver->ops == ops) { + list_del(&driver->vfio_next); + mutex_unlock(&vfio.iommu_drivers_lock); + kfree(driver); + return; + } + } + mutex_unlock(&vfio.iommu_drivers_lock); +} +EXPORT_SYMBOL_GPL(vfio_unregister_iommu_driver); + +/** + * Group minor allocation/free - both called with vfio.group_lock held + */ +static int vfio_alloc_group_minor(struct vfio_group *group) +{ + int ret, minor; + +again: + if (unlikely(idr_pre_get(&vfio.group_idr, GFP_KERNEL) == 0)) + return -ENOMEM; + + /* index 0 is used by /dev/vfio/vfio */ + ret = idr_get_new_above(&vfio.group_idr, group, 1, &minor); + if (ret == -EAGAIN) + goto again; + if (ret || minor > MINORMASK) { + if (minor > MINORMASK) + idr_remove(&vfio.group_idr, minor); + return -ENOSPC; + } + + return minor; +} + +static void vfio_free_group_minor(int minor) +{ + idr_remove(&vfio.group_idr, minor); +} + +static int vfio_iommu_group_notifier(struct notifier_block *nb, + unsigned long action, void *data); +static void vfio_group_get(struct vfio_group *group); + +/** + * Container objects - containers are created when /dev/vfio/vfio is + * opened, but their lifecycle extends until the last user is done, so + * it's freed via kref. Must support container/group/device being + * closed in any order. + */ +static void vfio_container_get(struct vfio_container *container) +{ + kref_get(&container->kref); +} + +static void vfio_container_release(struct kref *kref) +{ + struct vfio_container *container; + container = container_of(kref, struct vfio_container, kref); + + kfree(container); +} + +static void vfio_container_put(struct vfio_container *container) +{ + kref_put(&container->kref, vfio_container_release); +} + +/** + * Group objects - create, release, get, put, search + */ +static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group) +{ + struct vfio_group *group, *tmp; + struct device *dev; + int ret, minor; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) + return ERR_PTR(-ENOMEM); + + kref_init(&group->kref); + INIT_LIST_HEAD(&group->device_list); + mutex_init(&group->device_lock); + atomic_set(&group->container_users, 0); + group->iommu_group = iommu_group; + + group->nb.notifier_call = vfio_iommu_group_notifier; + + /* + * blocking notifiers acquire a rwsem around registering and hold + * it around callback. Therefore, need to register outside of + * vfio.group_lock to avoid A-B/B-A contention. Our callback won't + * do anything unless it can find the group in vfio.group_list, so + * no harm in registering early. + */ + ret = iommu_group_register_notifier(iommu_group, &group->nb); + if (ret) { + kfree(group); + return ERR_PTR(ret); + } + + mutex_lock(&vfio.group_lock); + + minor = vfio_alloc_group_minor(group); + if (minor < 0) { + mutex_unlock(&vfio.group_lock); + kfree(group); + return ERR_PTR(minor); + } + + /* Did we race creating this group? */ + list_for_each_entry(tmp, &vfio.group_list, vfio_next) { + if (tmp->iommu_group == iommu_group) { + vfio_group_get(tmp); + vfio_free_group_minor(minor); + mutex_unlock(&vfio.group_lock); + kfree(group); + return tmp; + } + } + + dev = device_create(vfio.class, NULL, MKDEV(MAJOR(vfio.devt), minor), + group, "%d", iommu_group_id(iommu_group)); + if (IS_ERR(dev)) { + vfio_free_group_minor(minor); + mutex_unlock(&vfio.group_lock); + kfree(group); + return (struct vfio_group *)dev; /* ERR_PTR */ + } + + group->minor = minor; + group->dev = dev; + + list_add(&group->vfio_next, &vfio.group_list); + + mutex_unlock(&vfio.group_lock); + + return group; +} + +static void vfio_group_release(struct kref *kref) +{ + struct vfio_group *group = container_of(kref, struct vfio_group, kref); + + WARN_ON(!list_empty(&group->device_list)); + + device_destroy(vfio.class, MKDEV(MAJOR(vfio.devt), group->minor)); + list_del(&group->vfio_next); + vfio_free_group_minor(group->minor); + + mutex_unlock(&vfio.group_lock); + + /* + * Unregister outside of lock. A spurious callback is harmless now + * that the group is no longer in vfio.group_list. + */ + iommu_group_unregister_notifier(group->iommu_group, &group->nb); + + kfree(group); +} + +static void vfio_group_put(struct vfio_group *group) +{ + mutex_lock(&vfio.group_lock); + /* + * Release needs to unlock to unregister the notifier, so only + * unlock if not released. + */ + if (!kref_put(&group->kref, vfio_group_release)) + mutex_unlock(&vfio.group_lock); +} + +/* Assume group_lock or group reference is held */ +static void vfio_group_get(struct vfio_group *group) +{ + kref_get(&group->kref); +} + +/* + * Not really a try as we will sleep for mutex, but we need to make + * sure the group pointer is valid under lock and get a reference. + */ +static struct vfio_group *vfio_group_try_get(struct vfio_group *group) +{ + struct vfio_group *target = group; + + mutex_lock(&vfio.group_lock); + list_for_each_entry(group, &vfio.group_list, vfio_next) { + if (group == target) { + vfio_group_get(group); + mutex_unlock(&vfio.group_lock); + return group; + } + } + mutex_unlock(&vfio.group_lock); + + return NULL; +} + +static +struct vfio_group *vfio_group_get_from_iommu(struct iommu_group *iommu_group) +{ + struct vfio_group *group; + + mutex_lock(&vfio.group_lock); + list_for_each_entry(group, &vfio.group_list, vfio_next) { + if (group->iommu_group == iommu_group) { + vfio_group_get(group); + mutex_unlock(&vfio.group_lock); + return group; + } + } + mutex_unlock(&vfio.group_lock); + + return NULL; +} + +static struct vfio_group *vfio_group_get_from_minor(int minor) +{ + struct vfio_group *group; + + mutex_lock(&vfio.group_lock); + group = idr_find(&vfio.group_idr, minor); + if (!group) { + mutex_unlock(&vfio.group_lock); + return NULL; + } + vfio_group_get(group); + mutex_unlock(&vfio.group_lock); + + return group; +} + +/** + * Device objects - create, release, get, put, search + */ +static +struct vfio_device *vfio_group_create_device(struct vfio_group *group, + struct device *dev, + const struct vfio_device_ops *ops, + void *device_data) +{ + struct vfio_device *device; + int ret; + + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + return ERR_PTR(-ENOMEM); + + kref_init(&device->kref); + device->dev = dev; + device->group = group; + device->ops = ops; + device->device_data = device_data; + + ret = dev_set_drvdata(dev, device); + if (ret) { + kfree(device); + return ERR_PTR(ret); + } + + /* No need to get group_lock, caller has group reference */ + vfio_group_get(group); + + mutex_lock(&group->device_lock); + list_add(&device->group_next, &group->device_list); + mutex_unlock(&group->device_lock); + + return device; +} + +static void vfio_device_release(struct kref *kref) +{ + struct vfio_device *device = container_of(kref, + struct vfio_device, kref); + struct vfio_group *group = device->group; + + mutex_lock(&group->device_lock); + list_del(&device->group_next); + mutex_unlock(&group->device_lock); + + dev_set_drvdata(device->dev, NULL); + + kfree(device); + + /* vfio_del_group_dev may be waiting for this device */ + wake_up(&vfio.release_q); +} + +/* Device reference always implies a group reference */ +static void vfio_device_put(struct vfio_device *device) +{ + kref_put(&device->kref, vfio_device_release); + vfio_group_put(device->group); +} + +static void vfio_device_get(struct vfio_device *device) +{ + vfio_group_get(device->group); + kref_get(&device->kref); +} + +static struct vfio_device *vfio_group_get_device(struct vfio_group *group, + struct device *dev) +{ + struct vfio_device *device; + + mutex_lock(&group->device_lock); + list_for_each_entry(device, &group->device_list, group_next) { + if (device->dev == dev) { + vfio_device_get(device); + mutex_unlock(&group->device_lock); + return device; + } + } + mutex_unlock(&group->device_lock); + return NULL; +} + +/* + * Whitelist some drivers that we know are safe (no dma) or just sit on + * a device. It's not always practical to leave a device within a group + * driverless as it could get re-bound to something unsafe. + */ +static const char * const vfio_driver_whitelist[] = { "pci-stub" }; + +static bool vfio_whitelisted_driver(struct device_driver *drv) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(vfio_driver_whitelist); i++) { + if (!strcmp(drv->name, vfio_driver_whitelist[i])) + return true; + } + + return false; +} + +/* + * A vfio group is viable for use by userspace if all devices are either + * driver-less or bound to a vfio or whitelisted driver. We test the + * latter by the existence of a struct vfio_device matching the dev. + */ +static int vfio_dev_viable(struct device *dev, void *data) +{ + struct vfio_group *group = data; + struct vfio_device *device; + + if (!dev->driver || vfio_whitelisted_driver(dev->driver)) + return 0; + + device = vfio_group_get_device(group, dev); + if (device) { + vfio_device_put(device); + return 0; + } + + return -EINVAL; +} + +/** + * Async device support + */ +static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev) +{ + struct vfio_device *device; + + /* Do we already know about it? We shouldn't */ + device = vfio_group_get_device(group, dev); + if (WARN_ON_ONCE(device)) { + vfio_device_put(device); + return 0; + } + + /* Nothing to do for idle groups */ + if (!atomic_read(&group->container_users)) + return 0; + + /* TODO Prevent device auto probing */ + WARN("Device %s added to live group %d!\n", dev_name(dev), + iommu_group_id(group->iommu_group)); + + return 0; +} + +static int vfio_group_nb_del_dev(struct vfio_group *group, struct device *dev) +{ + struct vfio_device *device; + + /* + * Expect to fall out here. If a device was in use, it would + * have been bound to a vfio sub-driver, which would have blocked + * in .remove at vfio_del_group_dev. Sanity check that we no + * longer track the device, so it's safe to remove. + */ + device = vfio_group_get_device(group, dev); + if (likely(!device)) + return 0; + + WARN("Device %s removed from live group %d!\n", dev_name(dev), + iommu_group_id(group->iommu_group)); + + vfio_device_put(device); + return 0; +} + +static int vfio_group_nb_verify(struct vfio_group *group, struct device *dev) +{ + /* We don't care what happens when the group isn't in use */ + if (!atomic_read(&group->container_users)) + return 0; + + return vfio_dev_viable(dev, group); +} + +static int vfio_iommu_group_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct vfio_group *group = container_of(nb, struct vfio_group, nb); + struct device *dev = data; + + /* + * Need to go through a group_lock lookup to get a reference or + * we risk racing a group being removed. Leave a WARN_ON for + * debuging, but if the group no longer exists, a spurious notify + * is harmless. + */ + group = vfio_group_try_get(group); + if (WARN_ON(!group)) + return NOTIFY_OK; + + switch (action) { + case IOMMU_GROUP_NOTIFY_ADD_DEVICE: + vfio_group_nb_add_dev(group, dev); + break; + case IOMMU_GROUP_NOTIFY_DEL_DEVICE: + vfio_group_nb_del_dev(group, dev); + break; + case IOMMU_GROUP_NOTIFY_BIND_DRIVER: + pr_debug("%s: Device %s, group %d binding to driver\n", + __func__, dev_name(dev), + iommu_group_id(group->iommu_group)); + break; + case IOMMU_GROUP_NOTIFY_BOUND_DRIVER: + pr_debug("%s: Device %s, group %d bound to driver %s\n", + __func__, dev_name(dev), + iommu_group_id(group->iommu_group), dev->driver->name); + BUG_ON(vfio_group_nb_verify(group, dev)); + break; + case IOMMU_GROUP_NOTIFY_UNBIND_DRIVER: + pr_debug("%s: Device %s, group %d unbinding from driver %s\n", + __func__, dev_name(dev), + iommu_group_id(group->iommu_group), dev->driver->name); + break; + case IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER: + pr_debug("%s: Device %s, group %d unbound from driver\n", + __func__, dev_name(dev), + iommu_group_id(group->iommu_group)); + /* + * XXX An unbound device in a live group is ok, but we'd + * really like to avoid the above BUG_ON by preventing other + * drivers from binding to it. Once that occurs, we have to + * stop the system to maintain isolation. At a minimum, we'd + * want a toggle to disable driver auto probe for this device. + */ + break; + } + + vfio_group_put(group); + return NOTIFY_OK; +} + +/** + * VFIO driver API + */ +int vfio_add_group_dev(struct device *dev, + const struct vfio_device_ops *ops, void *device_data) +{ + struct iommu_group *iommu_group; + struct vfio_group *group; + struct vfio_device *device; + + iommu_group = iommu_group_get(dev); + if (!iommu_group) + return -EINVAL; + + group = vfio_group_get_from_iommu(iommu_group); + if (!group) { + group = vfio_create_group(iommu_group); + if (IS_ERR(group)) { + iommu_group_put(iommu_group); + return PTR_ERR(group); + } + } + + device = vfio_group_get_device(group, dev); + if (device) { + WARN(1, "Device %s already exists on group %d\n", + dev_name(dev), iommu_group_id(iommu_group)); + vfio_device_put(device); + vfio_group_put(group); + iommu_group_put(iommu_group); + return -EBUSY; + } + + device = vfio_group_create_device(group, dev, ops, device_data); + if (IS_ERR(device)) { + vfio_group_put(group); + iommu_group_put(iommu_group); + return PTR_ERR(device); + } + + /* + * Added device holds reference to iommu_group and vfio_device + * (which in turn holds reference to vfio_group). Drop extra + * group reference used while acquiring device. + */ + vfio_group_put(group); + + return 0; +} +EXPORT_SYMBOL_GPL(vfio_add_group_dev); + +/* Test whether a struct device is present in our tracking */ +static bool vfio_dev_present(struct device *dev) +{ + struct iommu_group *iommu_group; + struct vfio_group *group; + struct vfio_device *device; + + iommu_group = iommu_group_get(dev); + if (!iommu_group) + return false; + + group = vfio_group_get_from_iommu(iommu_group); + if (!group) { + iommu_group_put(iommu_group); + return false; + } + + device = vfio_group_get_device(group, dev); + if (!device) { + vfio_group_put(group); + iommu_group_put(iommu_group); + return false; + } + + vfio_device_put(device); + vfio_group_put(group); + iommu_group_put(iommu_group); + return true; +} + +/* + * Decrement the device reference count and wait for the device to be + * removed. Open file descriptors for the device... */ +void *vfio_del_group_dev(struct device *dev) +{ + struct vfio_device *device = dev_get_drvdata(dev); + struct vfio_group *group = device->group; + struct iommu_group *iommu_group = group->iommu_group; + void *device_data = device->device_data; + + vfio_device_put(device); + + /* TODO send a signal to encourage this to be released */ + wait_event(vfio.release_q, !vfio_dev_present(dev)); + + iommu_group_put(iommu_group); + + return device_data; +} +EXPORT_SYMBOL_GPL(vfio_del_group_dev); + +/** + * VFIO base fd, /dev/vfio/vfio + */ +static long vfio_ioctl_check_extension(struct vfio_container *container, + unsigned long arg) +{ + struct vfio_iommu_driver *driver = container->iommu_driver; + long ret = 0; + + switch (arg) { + /* No base extensions yet */ + default: + /* + * If no driver is set, poll all registered drivers for + * extensions and return the first positive result. If + * a driver is already set, further queries will be passed + * only to that driver. + */ + if (!driver) { + mutex_lock(&vfio.iommu_drivers_lock); + list_for_each_entry(driver, &vfio.iommu_drivers_list, + vfio_next) { + if (!try_module_get(driver->ops->owner)) + continue; + + ret = driver->ops->ioctl(NULL, + VFIO_CHECK_EXTENSION, + arg); + module_put(driver->ops->owner); + if (ret > 0) + break; + } + mutex_unlock(&vfio.iommu_drivers_lock); + } else + ret = driver->ops->ioctl(container->iommu_data, + VFIO_CHECK_EXTENSION, arg); + } + + return ret; +} + +/* hold container->group_lock */ +static int __vfio_container_attach_groups(struct vfio_container *container, + struct vfio_iommu_driver *driver, + void *data) +{ + struct vfio_group *group; + int ret = -ENODEV; + + list_for_each_entry(group, &container->group_list, container_next) { + ret = driver->ops->attach_group(data, group->iommu_group); + if (ret) + goto unwind; + } + + return ret; + +unwind: + list_for_each_entry_continue_reverse(group, &container->group_list, + container_next) { + driver->ops->detach_group(data, group->iommu_group); + } + + return ret; +} + +static long vfio_ioctl_set_iommu(struct vfio_container *container, + unsigned long arg) +{ + struct vfio_iommu_driver *driver; + long ret = -ENODEV; + + mutex_lock(&container->group_lock); + + /* + * The container is designed to be an unprivileged interface while + * the group can be assigned to specific users. Therefore, only by + * adding a group to a container does the user get the privilege of + * enabling the iommu, which may allocate finite resources. There + * is no unset_iommu, but by removing all the groups from a container, + * the container is deprivileged and returns to an unset state. + */ + if (list_empty(&container->group_list) || container->iommu_driver) { + mutex_unlock(&container->group_lock); + return -EINVAL; + } + + mutex_lock(&vfio.iommu_drivers_lock); + list_for_each_entry(driver, &vfio.iommu_drivers_list, vfio_next) { + void *data; + + if (!try_module_get(driver->ops->owner)) + continue; + + /* + * The arg magic for SET_IOMMU is the same as CHECK_EXTENSION, + * so test which iommu driver reported support for this + * extension and call open on them. We also pass them the + * magic, allowing a single driver to support multiple + * interfaces if they'd like. + */ + if (driver->ops->ioctl(NULL, VFIO_CHECK_EXTENSION, arg) <= 0) { + module_put(driver->ops->owner); + continue; + } + + /* module reference holds the driver we're working on */ + mutex_unlock(&vfio.iommu_drivers_lock); + + data = driver->ops->open(arg); + if (IS_ERR(data)) { + ret = PTR_ERR(data); + module_put(driver->ops->owner); + goto skip_drivers_unlock; + } + + ret = __vfio_container_attach_groups(container, driver, data); + if (!ret) { + container->iommu_driver = driver; + container->iommu_data = data; + } else { + driver->ops->release(data); + module_put(driver->ops->owner); + } + + goto skip_drivers_unlock; + } + + mutex_unlock(&vfio.iommu_drivers_lock); +skip_drivers_unlock: + mutex_unlock(&container->group_lock); + + return ret; +} + +static long vfio_fops_unl_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + struct vfio_container *container = filep->private_data; + struct vfio_iommu_driver *driver; + void *data; + long ret = -EINVAL; + + if (!container) + return ret; + + driver = container->iommu_driver; + data = container->iommu_data; + + switch (cmd) { + case VFIO_GET_API_VERSION: + ret = VFIO_API_VERSION; + break; + case VFIO_CHECK_EXTENSION: + ret = vfio_ioctl_check_extension(container, arg); + break; + case VFIO_SET_IOMMU: + ret = vfio_ioctl_set_iommu(container, arg); + break; + default: + if (driver) /* passthrough all unrecognized ioctls */ + ret = driver->ops->ioctl(data, cmd, arg); + } + + return ret; +} + +#ifdef CONFIG_COMPAT +static long vfio_fops_compat_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + arg = (unsigned long)compat_ptr(arg); + return vfio_fops_unl_ioctl(filep, cmd, arg); +} +#endif /* CONFIG_COMPAT */ + +static int vfio_fops_open(struct inode *inode, struct file *filep) +{ + struct vfio_container *container; + + container = kzalloc(sizeof(*container), GFP_KERNEL); + if (!container) + return -ENOMEM; + + INIT_LIST_HEAD(&container->group_list); + mutex_init(&container->group_lock); + kref_init(&container->kref); + + filep->private_data = container; + + return 0; +} + +static int vfio_fops_release(struct inode *inode, struct file *filep) +{ + struct vfio_container *container = filep->private_data; + + filep->private_data = NULL; + + vfio_container_put(container); + + return 0; +} + +/* + * Once an iommu driver is set, we optionally pass read/write/mmap + * on to the driver, allowing management interfaces beyond ioctl. + */ +static ssize_t vfio_fops_read(struct file *filep, char __user *buf, + size_t count, loff_t *ppos) +{ + struct vfio_container *container = filep->private_data; + struct vfio_iommu_driver *driver = container->iommu_driver; + + if (unlikely(!driver || !driver->ops->read)) + return -EINVAL; + + return driver->ops->read(container->iommu_data, buf, count, ppos); +} + +static ssize_t vfio_fops_write(struct file *filep, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct vfio_container *container = filep->private_data; + struct vfio_iommu_driver *driver = container->iommu_driver; + + if (unlikely(!driver || !driver->ops->write)) + return -EINVAL; + + return driver->ops->write(container->iommu_data, buf, count, ppos); +} + +static int vfio_fops_mmap(struct file *filep, struct vm_area_struct *vma) +{ + struct vfio_container *container = filep->private_data; + struct vfio_iommu_driver *driver = container->iommu_driver; + + if (unlikely(!driver || !driver->ops->mmap)) + return -EINVAL; + + return driver->ops->mmap(container->iommu_data, vma); +} + +static const struct file_operations vfio_fops = { + .owner = THIS_MODULE, + .open = vfio_fops_open, + .release = vfio_fops_release, + .read = vfio_fops_read, + .write = vfio_fops_write, + .unlocked_ioctl = vfio_fops_unl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vfio_fops_compat_ioctl, +#endif + .mmap = vfio_fops_mmap, +}; + +/** + * VFIO Group fd, /dev/vfio/$GROUP + */ +static void __vfio_group_unset_container(struct vfio_group *group) +{ + struct vfio_container *container = group->container; + struct vfio_iommu_driver *driver; + + mutex_lock(&container->group_lock); + + driver = container->iommu_driver; + if (driver) + driver->ops->detach_group(container->iommu_data, + group->iommu_group); + + group->container = NULL; + list_del(&group->container_next); + + /* Detaching the last group deprivileges a container, remove iommu */ + if (driver && list_empty(&container->group_list)) { + driver->ops->release(container->iommu_data); + module_put(driver->ops->owner); + container->iommu_driver = NULL; + container->iommu_data = NULL; + } + + mutex_unlock(&container->group_lock); + + vfio_container_put(container); +} + +/* + * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or + * if there was no container to unset. Since the ioctl is called on + * the group, we know that still exists, therefore the only valid + * transition here is 1->0. + */ +static int vfio_group_unset_container(struct vfio_group *group) +{ + int users = atomic_cmpxchg(&group->container_users, 1, 0); + + if (!users) + return -EINVAL; + if (users != 1) + return -EBUSY; + + __vfio_group_unset_container(group); + + return 0; +} + +/* + * When removing container users, anything that removes the last user + * implicitly removes the group from the container. That is, if the + * group file descriptor is closed, as well as any device file descriptors, + * the group is free. + */ +static void vfio_group_try_dissolve_container(struct vfio_group *group) +{ + if (0 == atomic_dec_if_positive(&group->container_users)) + __vfio_group_unset_container(group); +} + +static int vfio_group_set_container(struct vfio_group *group, int container_fd) +{ + struct file *filep; + struct vfio_container *container; + struct vfio_iommu_driver *driver; + int ret = 0; + + if (atomic_read(&group->container_users)) + return -EINVAL; + + filep = fget(container_fd); + if (!filep) + return -EBADF; + + /* Sanity check, is this really our fd? */ + if (filep->f_op != &vfio_fops) { + fput(filep); + return -EINVAL; + } + + container = filep->private_data; + WARN_ON(!container); /* fget ensures we don't race vfio_release */ + + mutex_lock(&container->group_lock); + + driver = container->iommu_driver; + if (driver) { + ret = driver->ops->attach_group(container->iommu_data, + group->iommu_group); + if (ret) + goto unlock_out; + } + + group->container = container; + list_add(&group->container_next, &container->group_list); + + /* Get a reference on the container and mark a user within the group */ + vfio_container_get(container); + atomic_inc(&group->container_users); + +unlock_out: + mutex_unlock(&container->group_lock); + fput(filep); + + return ret; +} + +static bool vfio_group_viable(struct vfio_group *group) +{ + return (iommu_group_for_each_dev(group->iommu_group, + group, vfio_dev_viable) == 0); +} + +static const struct file_operations vfio_device_fops; + +static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) +{ + struct vfio_device *device; + struct file *filep; + int ret = -ENODEV; + + if (0 == atomic_read(&group->container_users) || + !group->container->iommu_driver || !vfio_group_viable(group)) + return -EINVAL; + + mutex_lock(&group->device_lock); + list_for_each_entry(device, &group->device_list, group_next) { + if (strcmp(dev_name(device->dev), buf)) + continue; + + ret = device->ops->open(device->device_data); + if (ret) + break; + /* + * We can't use anon_inode_getfd() because we need to modify + * the f_mode flags directly to allow more than just ioctls + */ + ret = get_unused_fd(); + if (ret < 0) { + device->ops->release(device->device_data); + break; + } + + filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, + device, O_RDWR); + if (IS_ERR(filep)) { + put_unused_fd(ret); + ret = PTR_ERR(filep); + device->ops->release(device->device_data); + break; + } + + /* + * TODO: add an anon_inode interface to do this. + * Appears to be missing by lack of need rather than + * explicitly prevented. Now there's need. + */ + filep->f_mode |= (FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE); + + fd_install(ret, filep); + + vfio_device_get(device); + atomic_inc(&group->container_users); + break; + } + mutex_unlock(&group->device_lock); + + return ret; +} + +static long vfio_group_fops_unl_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + struct vfio_group *group = filep->private_data; + long ret = -ENOTTY; + + switch (cmd) { + case VFIO_GROUP_GET_STATUS: + { + struct vfio_group_status status; + unsigned long minsz; + + minsz = offsetofend(struct vfio_group_status, flags); + + if (copy_from_user(&status, (void __user *)arg, minsz)) + return -EFAULT; + + if (status.argsz < minsz) + return -EINVAL; + + status.flags = 0; + + if (vfio_group_viable(group)) + status.flags |= VFIO_GROUP_FLAGS_VIABLE; + + if (group->container) + status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET; + + if (copy_to_user((void __user *)arg, &status, minsz)) + return -EFAULT; + + ret = 0; + break; + } + case VFIO_GROUP_SET_CONTAINER: + { + int fd; + + if (get_user(fd, (int __user *)arg)) + return -EFAULT; + + if (fd < 0) + return -EINVAL; + + ret = vfio_group_set_container(group, fd); + break; + } + case VFIO_GROUP_UNSET_CONTAINER: + ret = vfio_group_unset_container(group); + break; + case VFIO_GROUP_GET_DEVICE_FD: + { + char *buf; + + buf = strndup_user((const char __user *)arg, PAGE_SIZE); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = vfio_group_get_device_fd(group, buf); + kfree(buf); + break; + } + } + + return ret; +} + +#ifdef CONFIG_COMPAT +static long vfio_group_fops_compat_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + arg = (unsigned long)compat_ptr(arg); + return vfio_group_fops_unl_ioctl(filep, cmd, arg); +} +#endif /* CONFIG_COMPAT */ + +static int vfio_group_fops_open(struct inode *inode, struct file *filep) +{ + struct vfio_group *group; + + group = vfio_group_get_from_minor(iminor(inode)); + if (!group) + return -ENODEV; + + if (group->container) { + vfio_group_put(group); + return -EBUSY; + } + + filep->private_data = group; + + return 0; +} + +static int vfio_group_fops_release(struct inode *inode, struct file *filep) +{ + struct vfio_group *group = filep->private_data; + + filep->private_data = NULL; + + vfio_group_try_dissolve_container(group); + + vfio_group_put(group); + + return 0; +} + +static const struct file_operations vfio_group_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = vfio_group_fops_unl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vfio_group_fops_compat_ioctl, +#endif + .open = vfio_group_fops_open, + .release = vfio_group_fops_release, +}; + +/** + * VFIO Device fd + */ +static int vfio_device_fops_release(struct inode *inode, struct file *filep) +{ + struct vfio_device *device = filep->private_data; + + device->ops->release(device->device_data); + + vfio_group_try_dissolve_container(device->group); + + vfio_device_put(device); + + return 0; +} + +static long vfio_device_fops_unl_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + struct vfio_device *device = filep->private_data; + + if (unlikely(!device->ops->ioctl)) + return -EINVAL; + + return device->ops->ioctl(device->device_data, cmd, arg); +} + +static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf, + size_t count, loff_t *ppos) +{ + struct vfio_device *device = filep->private_data; + + if (unlikely(!device->ops->read)) + return -EINVAL; + + return device->ops->read(device->device_data, buf, count, ppos); +} + +static ssize_t vfio_device_fops_write(struct file *filep, + const char __user *buf, + size_t count, loff_t *ppos) +{ + struct vfio_device *device = filep->private_data; + + if (unlikely(!device->ops->write)) + return -EINVAL; + + return device->ops->write(device->device_data, buf, count, ppos); +} + +static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma) +{ + struct vfio_device *device = filep->private_data; + + if (unlikely(!device->ops->mmap)) + return -EINVAL; + + return device->ops->mmap(device->device_data, vma); +} + +#ifdef CONFIG_COMPAT +static long vfio_device_fops_compat_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + arg = (unsigned long)compat_ptr(arg); + return vfio_device_fops_unl_ioctl(filep, cmd, arg); +} +#endif /* CONFIG_COMPAT */ + +static const struct file_operations vfio_device_fops = { + .owner = THIS_MODULE, + .release = vfio_device_fops_release, + .read = vfio_device_fops_read, + .write = vfio_device_fops_write, + .unlocked_ioctl = vfio_device_fops_unl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vfio_device_fops_compat_ioctl, +#endif + .mmap = vfio_device_fops_mmap, +}; + +/** + * Module/class support + */ +static char *vfio_devnode(struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev)); +} + +static int __init vfio_init(void) +{ + int ret; + + idr_init(&vfio.group_idr); + mutex_init(&vfio.group_lock); + mutex_init(&vfio.iommu_drivers_lock); + INIT_LIST_HEAD(&vfio.group_list); + INIT_LIST_HEAD(&vfio.iommu_drivers_list); + init_waitqueue_head(&vfio.release_q); + + vfio.class = class_create(THIS_MODULE, "vfio"); + if (IS_ERR(vfio.class)) { + ret = PTR_ERR(vfio.class); + goto err_class; + } + + vfio.class->devnode = vfio_devnode; + + ret = alloc_chrdev_region(&vfio.devt, 0, MINORMASK, "vfio"); + if (ret) + goto err_base_chrdev; + + cdev_init(&vfio.cdev, &vfio_fops); + ret = cdev_add(&vfio.cdev, vfio.devt, 1); + if (ret) + goto err_base_cdev; + + vfio.dev = device_create(vfio.class, NULL, vfio.devt, NULL, "vfio"); + if (IS_ERR(vfio.dev)) { + ret = PTR_ERR(vfio.dev); + goto err_base_dev; + } + + /* /dev/vfio/$GROUP */ + cdev_init(&vfio.group_cdev, &vfio_group_fops); + ret = cdev_add(&vfio.group_cdev, + MKDEV(MAJOR(vfio.devt), 1), MINORMASK - 1); + if (ret) + goto err_groups_cdev; + + pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); + + /* + * Attempt to load known iommu-drivers. This gives us a working + * environment without the user needing to explicitly load iommu + * drivers. + */ + request_module_nowait("vfio_iommu_type1"); + + return 0; + +err_groups_cdev: + device_destroy(vfio.class, vfio.devt); +err_base_dev: + cdev_del(&vfio.cdev); +err_base_cdev: + unregister_chrdev_region(vfio.devt, MINORMASK); +err_base_chrdev: + class_destroy(vfio.class); + vfio.class = NULL; +err_class: + return ret; +} + +static void __exit vfio_cleanup(void) +{ + WARN_ON(!list_empty(&vfio.group_list)); + + idr_destroy(&vfio.group_idr); + cdev_del(&vfio.group_cdev); + device_destroy(vfio.class, vfio.devt); + cdev_del(&vfio.cdev); + unregister_chrdev_region(vfio.devt, MINORMASK); + class_destroy(vfio.class); + vfio.class = NULL; +} + +module_init(vfio_init); +module_exit(vfio_cleanup); + +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c new file mode 100644 index 000000000000..6f3fbc48a6c7 --- /dev/null +++ b/drivers/vfio/vfio_iommu_type1.c @@ -0,0 +1,753 @@ +/* + * VFIO: IOMMU DMA mapping support for Type1 IOMMU + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@redhat.com> + * + * 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. + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@cisco.com + * + * We arbitrarily define a Type1 IOMMU as one matching the below code. + * It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel + * VT-d, but that makes it harder to re-use as theoretically anyone + * implementing a similar IOMMU could make use of this. We expect the + * IOMMU to support the IOMMU API and have few to no restrictions around + * the IOVA range that can be mapped. The Type1 IOMMU is currently + * optimized for relatively static mappings of a userspace process with + * userpsace pages pinned into memory. We also assume devices and IOMMU + * domains are PCI based as the IOMMU API is still centered around a + * device/bus interface rather than a group interface. + */ + +#include <linux/compat.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/iommu.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/pci.h> /* pci_bus_type */ +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/vfio.h> +#include <linux/workqueue.h> + +#define DRIVER_VERSION "0.2" +#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" +#define DRIVER_DESC "Type1 IOMMU driver for VFIO" + +static bool allow_unsafe_interrupts; +module_param_named(allow_unsafe_interrupts, + allow_unsafe_interrupts, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(allow_unsafe_interrupts, + "Enable VFIO IOMMU support for on platforms without interrupt remapping support."); + +struct vfio_iommu { + struct iommu_domain *domain; + struct mutex lock; + struct list_head dma_list; + struct list_head group_list; + bool cache; +}; + +struct vfio_dma { + struct list_head next; + dma_addr_t iova; /* Device address */ + unsigned long vaddr; /* Process virtual addr */ + long npage; /* Number of pages */ + int prot; /* IOMMU_READ/WRITE */ +}; + +struct vfio_group { + struct iommu_group *iommu_group; + struct list_head next; +}; + +/* + * This code handles mapping and unmapping of user data buffers + * into DMA'ble space using the IOMMU + */ + +#define NPAGE_TO_SIZE(npage) ((size_t)(npage) << PAGE_SHIFT) + +struct vwork { + struct mm_struct *mm; + long npage; + struct work_struct work; +}; + +/* delayed decrement/increment for locked_vm */ +static void vfio_lock_acct_bg(struct work_struct *work) +{ + struct vwork *vwork = container_of(work, struct vwork, work); + struct mm_struct *mm; + + mm = vwork->mm; + down_write(&mm->mmap_sem); + mm->locked_vm += vwork->npage; + up_write(&mm->mmap_sem); + mmput(mm); + kfree(vwork); +} + +static void vfio_lock_acct(long npage) +{ + struct vwork *vwork; + struct mm_struct *mm; + + if (!current->mm) + return; /* process exited */ + + if (down_write_trylock(¤t->mm->mmap_sem)) { + current->mm->locked_vm += npage; + up_write(¤t->mm->mmap_sem); + return; + } + + /* + * Couldn't get mmap_sem lock, so must setup to update + * mm->locked_vm later. If locked_vm were atomic, we + * wouldn't need this silliness + */ + vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL); + if (!vwork) + return; + mm = get_task_mm(current); + if (!mm) { + kfree(vwork); + return; + } + INIT_WORK(&vwork->work, vfio_lock_acct_bg); + vwork->mm = mm; + vwork->npage = npage; + schedule_work(&vwork->work); +} + +/* + * Some mappings aren't backed by a struct page, for example an mmap'd + * MMIO range for our own or another device. These use a different + * pfn conversion and shouldn't be tracked as locked pages. + */ +static bool is_invalid_reserved_pfn(unsigned long pfn) +{ + if (pfn_valid(pfn)) { + bool reserved; + struct page *tail = pfn_to_page(pfn); + struct page *head = compound_trans_head(tail); + reserved = !!(PageReserved(head)); + if (head != tail) { + /* + * "head" is not a dangling pointer + * (compound_trans_head takes care of that) + * but the hugepage may have been split + * from under us (and we may not hold a + * reference count on the head page so it can + * be reused before we run PageReferenced), so + * we've to check PageTail before returning + * what we just read. + */ + smp_rmb(); + if (PageTail(tail)) + return reserved; + } + return PageReserved(tail); + } + + return true; +} + +static int put_pfn(unsigned long pfn, int prot) +{ + if (!is_invalid_reserved_pfn(pfn)) { + struct page *page = pfn_to_page(pfn); + if (prot & IOMMU_WRITE) + SetPageDirty(page); + put_page(page); + return 1; + } + return 0; +} + +/* Unmap DMA region */ +static long __vfio_dma_do_unmap(struct vfio_iommu *iommu, dma_addr_t iova, + long npage, int prot) +{ + long i, unlocked = 0; + + for (i = 0; i < npage; i++, iova += PAGE_SIZE) { + unsigned long pfn; + + pfn = iommu_iova_to_phys(iommu->domain, iova) >> PAGE_SHIFT; + if (pfn) { + iommu_unmap(iommu->domain, iova, PAGE_SIZE); + unlocked += put_pfn(pfn, prot); + } + } + return unlocked; +} + +static void vfio_dma_unmap(struct vfio_iommu *iommu, dma_addr_t iova, + long npage, int prot) +{ + long unlocked; + + unlocked = __vfio_dma_do_unmap(iommu, iova, npage, prot); + vfio_lock_acct(-unlocked); +} + +static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) +{ + struct page *page[1]; + struct vm_area_struct *vma; + int ret = -EFAULT; + + if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) { + *pfn = page_to_pfn(page[0]); + return 0; + } + + down_read(¤t->mm->mmap_sem); + + vma = find_vma_intersection(current->mm, vaddr, vaddr + 1); + + if (vma && vma->vm_flags & VM_PFNMAP) { + *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; + if (is_invalid_reserved_pfn(*pfn)) + ret = 0; + } + + up_read(¤t->mm->mmap_sem); + + return ret; +} + +/* Map DMA region */ +static int __vfio_dma_map(struct vfio_iommu *iommu, dma_addr_t iova, + unsigned long vaddr, long npage, int prot) +{ + dma_addr_t start = iova; + long i, locked = 0; + int ret; + + /* Verify that pages are not already mapped */ + for (i = 0; i < npage; i++, iova += PAGE_SIZE) + if (iommu_iova_to_phys(iommu->domain, iova)) + return -EBUSY; + + iova = start; + + if (iommu->cache) + prot |= IOMMU_CACHE; + + /* + * XXX We break mappings into pages and use get_user_pages_fast to + * pin the pages in memory. It's been suggested that mlock might + * provide a more efficient mechanism, but nothing prevents the + * user from munlocking the pages, which could then allow the user + * access to random host memory. We also have no guarantee from the + * IOMMU API that the iommu driver can unmap sub-pages of previous + * mappings. This means we might lose an entire range if a single + * page within it is unmapped. Single page mappings are inefficient, + * but provide the most flexibility for now. + */ + for (i = 0; i < npage; i++, iova += PAGE_SIZE, vaddr += PAGE_SIZE) { + unsigned long pfn = 0; + + ret = vaddr_get_pfn(vaddr, prot, &pfn); + if (ret) { + __vfio_dma_do_unmap(iommu, start, i, prot); + return ret; + } + + /* + * Only add actual locked pages to accounting + * XXX We're effectively marking a page locked for every + * IOVA page even though it's possible the user could be + * backing multiple IOVAs with the same vaddr. This over- + * penalizes the user process, but we currently have no + * easy way to do this properly. + */ + if (!is_invalid_reserved_pfn(pfn)) + locked++; + + ret = iommu_map(iommu->domain, iova, + (phys_addr_t)pfn << PAGE_SHIFT, + PAGE_SIZE, prot); + if (ret) { + /* Back out mappings on error */ + put_pfn(pfn, prot); + __vfio_dma_do_unmap(iommu, start, i, prot); + return ret; + } + } + vfio_lock_acct(locked); + return 0; +} + +static inline bool ranges_overlap(dma_addr_t start1, size_t size1, + dma_addr_t start2, size_t size2) +{ + if (start1 < start2) + return (start2 - start1 < size1); + else if (start2 < start1) + return (start1 - start2 < size2); + return (size1 > 0 && size2 > 0); +} + +static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, + dma_addr_t start, size_t size) +{ + struct vfio_dma *dma; + + list_for_each_entry(dma, &iommu->dma_list, next) { + if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage), + start, size)) + return dma; + } + return NULL; +} + +static long vfio_remove_dma_overlap(struct vfio_iommu *iommu, dma_addr_t start, + size_t size, struct vfio_dma *dma) +{ + struct vfio_dma *split; + long npage_lo, npage_hi; + + /* Existing dma region is completely covered, unmap all */ + if (start <= dma->iova && + start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) { + vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot); + list_del(&dma->next); + npage_lo = dma->npage; + kfree(dma); + return npage_lo; + } + + /* Overlap low address of existing range */ + if (start <= dma->iova) { + size_t overlap; + + overlap = start + size - dma->iova; + npage_lo = overlap >> PAGE_SHIFT; + + vfio_dma_unmap(iommu, dma->iova, npage_lo, dma->prot); + dma->iova += overlap; + dma->vaddr += overlap; + dma->npage -= npage_lo; + return npage_lo; + } + + /* Overlap high address of existing range */ + if (start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) { + size_t overlap; + + overlap = dma->iova + NPAGE_TO_SIZE(dma->npage) - start; + npage_hi = overlap >> PAGE_SHIFT; + + vfio_dma_unmap(iommu, start, npage_hi, dma->prot); + dma->npage -= npage_hi; + return npage_hi; + } + + /* Split existing */ + npage_lo = (start - dma->iova) >> PAGE_SHIFT; + npage_hi = dma->npage - (size >> PAGE_SHIFT) - npage_lo; + + split = kzalloc(sizeof *split, GFP_KERNEL); + if (!split) + return -ENOMEM; + + vfio_dma_unmap(iommu, start, size >> PAGE_SHIFT, dma->prot); + + dma->npage = npage_lo; + + split->npage = npage_hi; + split->iova = start + size; + split->vaddr = dma->vaddr + NPAGE_TO_SIZE(npage_lo) + size; + split->prot = dma->prot; + list_add(&split->next, &iommu->dma_list); + return size >> PAGE_SHIFT; +} + +static int vfio_dma_do_unmap(struct vfio_iommu *iommu, + struct vfio_iommu_type1_dma_unmap *unmap) +{ + long ret = 0, npage = unmap->size >> PAGE_SHIFT; + struct vfio_dma *dma, *tmp; + uint64_t mask; + + mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1; + + if (unmap->iova & mask) + return -EINVAL; + if (unmap->size & mask) + return -EINVAL; + + /* XXX We still break these down into PAGE_SIZE */ + WARN_ON(mask & PAGE_MASK); + + mutex_lock(&iommu->lock); + + list_for_each_entry_safe(dma, tmp, &iommu->dma_list, next) { + if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage), + unmap->iova, unmap->size)) { + ret = vfio_remove_dma_overlap(iommu, unmap->iova, + unmap->size, dma); + if (ret > 0) + npage -= ret; + if (ret < 0 || npage == 0) + break; + } + } + mutex_unlock(&iommu->lock); + return ret > 0 ? 0 : (int)ret; +} + +static int vfio_dma_do_map(struct vfio_iommu *iommu, + struct vfio_iommu_type1_dma_map *map) +{ + struct vfio_dma *dma, *pdma = NULL; + dma_addr_t iova = map->iova; + unsigned long locked, lock_limit, vaddr = map->vaddr; + size_t size = map->size; + int ret = 0, prot = 0; + uint64_t mask; + long npage; + + mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1; + + /* READ/WRITE from device perspective */ + if (map->flags & VFIO_DMA_MAP_FLAG_WRITE) + prot |= IOMMU_WRITE; + if (map->flags & VFIO_DMA_MAP_FLAG_READ) + prot |= IOMMU_READ; + + if (!prot) + return -EINVAL; /* No READ/WRITE? */ + + if (vaddr & mask) + return -EINVAL; + if (iova & mask) + return -EINVAL; + if (size & mask) + return -EINVAL; + + /* XXX We still break these down into PAGE_SIZE */ + WARN_ON(mask & PAGE_MASK); + + /* Don't allow IOVA wrap */ + if (iova + size && iova + size < iova) + return -EINVAL; + + /* Don't allow virtual address wrap */ + if (vaddr + size && vaddr + size < vaddr) + return -EINVAL; + + npage = size >> PAGE_SHIFT; + if (!npage) + return -EINVAL; + + mutex_lock(&iommu->lock); + + if (vfio_find_dma(iommu, iova, size)) { + ret = -EBUSY; + goto out_lock; + } + + /* account for locked pages */ + locked = current->mm->locked_vm + npage; + lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { + pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", + __func__, rlimit(RLIMIT_MEMLOCK)); + ret = -ENOMEM; + goto out_lock; + } + + ret = __vfio_dma_map(iommu, iova, vaddr, npage, prot); + if (ret) + goto out_lock; + + /* Check if we abut a region below - nothing below 0 */ + if (iova) { + dma = vfio_find_dma(iommu, iova - 1, 1); + if (dma && dma->prot == prot && + dma->vaddr + NPAGE_TO_SIZE(dma->npage) == vaddr) { + + dma->npage += npage; + iova = dma->iova; + vaddr = dma->vaddr; + npage = dma->npage; + size = NPAGE_TO_SIZE(npage); + + pdma = dma; + } + } + + /* Check if we abut a region above - nothing above ~0 + 1 */ + if (iova + size) { + dma = vfio_find_dma(iommu, iova + size, 1); + if (dma && dma->prot == prot && + dma->vaddr == vaddr + size) { + + dma->npage += npage; + dma->iova = iova; + dma->vaddr = vaddr; + + /* + * If merged above and below, remove previously + * merged entry. New entry covers it. + */ + if (pdma) { + list_del(&pdma->next); + kfree(pdma); + } + pdma = dma; + } + } + + /* Isolated, new region */ + if (!pdma) { + dma = kzalloc(sizeof *dma, GFP_KERNEL); + if (!dma) { + ret = -ENOMEM; + vfio_dma_unmap(iommu, iova, npage, prot); + goto out_lock; + } + + dma->npage = npage; + dma->iova = iova; + dma->vaddr = vaddr; + dma->prot = prot; + list_add(&dma->next, &iommu->dma_list); + } + +out_lock: + mutex_unlock(&iommu->lock); + return ret; +} + +static int vfio_iommu_type1_attach_group(void *iommu_data, + struct iommu_group *iommu_group) +{ + struct vfio_iommu *iommu = iommu_data; + struct vfio_group *group, *tmp; + int ret; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) + return -ENOMEM; + + mutex_lock(&iommu->lock); + + list_for_each_entry(tmp, &iommu->group_list, next) { + if (tmp->iommu_group == iommu_group) { + mutex_unlock(&iommu->lock); + kfree(group); + return -EINVAL; + } + } + + /* + * TODO: Domain have capabilities that might change as we add + * groups (see iommu->cache, currently never set). Check for + * them and potentially disallow groups to be attached when it + * would change capabilities (ugh). + */ + ret = iommu_attach_group(iommu->domain, iommu_group); + if (ret) { + mutex_unlock(&iommu->lock); + kfree(group); + return ret; + } + + group->iommu_group = iommu_group; + list_add(&group->next, &iommu->group_list); + + mutex_unlock(&iommu->lock); + + return 0; +} + +static void vfio_iommu_type1_detach_group(void *iommu_data, + struct iommu_group *iommu_group) +{ + struct vfio_iommu *iommu = iommu_data; + struct vfio_group *group; + + mutex_lock(&iommu->lock); + + list_for_each_entry(group, &iommu->group_list, next) { + if (group->iommu_group == iommu_group) { + iommu_detach_group(iommu->domain, iommu_group); + list_del(&group->next); + kfree(group); + break; + } + } + + mutex_unlock(&iommu->lock); +} + +static void *vfio_iommu_type1_open(unsigned long arg) +{ + struct vfio_iommu *iommu; + + if (arg != VFIO_TYPE1_IOMMU) + return ERR_PTR(-EINVAL); + + iommu = kzalloc(sizeof(*iommu), GFP_KERNEL); + if (!iommu) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&iommu->group_list); + INIT_LIST_HEAD(&iommu->dma_list); + mutex_init(&iommu->lock); + + /* + * Wish we didn't have to know about bus_type here. + */ + iommu->domain = iommu_domain_alloc(&pci_bus_type); + if (!iommu->domain) { + kfree(iommu); + return ERR_PTR(-EIO); + } + + /* + * Wish we could specify required capabilities rather than create + * a domain, see what comes out and hope it doesn't change along + * the way. Fortunately we know interrupt remapping is global for + * our iommus. + */ + if (!allow_unsafe_interrupts && + !iommu_domain_has_cap(iommu->domain, IOMMU_CAP_INTR_REMAP)) { + pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n", + __func__); + iommu_domain_free(iommu->domain); + kfree(iommu); + return ERR_PTR(-EPERM); + } + + return iommu; +} + +static void vfio_iommu_type1_release(void *iommu_data) +{ + struct vfio_iommu *iommu = iommu_data; + struct vfio_group *group, *group_tmp; + struct vfio_dma *dma, *dma_tmp; + + list_for_each_entry_safe(group, group_tmp, &iommu->group_list, next) { + iommu_detach_group(iommu->domain, group->iommu_group); + list_del(&group->next); + kfree(group); + } + + list_for_each_entry_safe(dma, dma_tmp, &iommu->dma_list, next) { + vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot); + list_del(&dma->next); + kfree(dma); + } + + iommu_domain_free(iommu->domain); + iommu->domain = NULL; + kfree(iommu); +} + +static long vfio_iommu_type1_ioctl(void *iommu_data, + unsigned int cmd, unsigned long arg) +{ + struct vfio_iommu *iommu = iommu_data; + unsigned long minsz; + + if (cmd == VFIO_CHECK_EXTENSION) { + switch (arg) { + case VFIO_TYPE1_IOMMU: + return 1; + default: + return 0; + } + } else if (cmd == VFIO_IOMMU_GET_INFO) { + struct vfio_iommu_type1_info info; + + minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + info.flags = 0; + + info.iova_pgsizes = iommu->domain->ops->pgsize_bitmap; + + return copy_to_user((void __user *)arg, &info, minsz); + + } else if (cmd == VFIO_IOMMU_MAP_DMA) { + struct vfio_iommu_type1_dma_map map; + uint32_t mask = VFIO_DMA_MAP_FLAG_READ | + VFIO_DMA_MAP_FLAG_WRITE; + + minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); + + if (copy_from_user(&map, (void __user *)arg, minsz)) + return -EFAULT; + + if (map.argsz < minsz || map.flags & ~mask) + return -EINVAL; + + return vfio_dma_do_map(iommu, &map); + + } else if (cmd == VFIO_IOMMU_UNMAP_DMA) { + struct vfio_iommu_type1_dma_unmap unmap; + + minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size); + + if (copy_from_user(&unmap, (void __user *)arg, minsz)) + return -EFAULT; + + if (unmap.argsz < minsz || unmap.flags) + return -EINVAL; + + return vfio_dma_do_unmap(iommu, &unmap); + } + + return -ENOTTY; +} + +static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { + .name = "vfio-iommu-type1", + .owner = THIS_MODULE, + .open = vfio_iommu_type1_open, + .release = vfio_iommu_type1_release, + .ioctl = vfio_iommu_type1_ioctl, + .attach_group = vfio_iommu_type1_attach_group, + .detach_group = vfio_iommu_type1_detach_group, +}; + +static int __init vfio_iommu_type1_init(void) +{ + if (!iommu_present(&pci_bus_type)) + return -ENODEV; + + return vfio_register_iommu_driver(&vfio_iommu_driver_ops_type1); +} + +static void __exit vfio_iommu_type1_cleanup(void) +{ + vfio_unregister_iommu_driver(&vfio_iommu_driver_ops_type1); +} + +module_init(vfio_iommu_type1_init); +module_exit(vfio_iommu_type1_cleanup); + +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); |