Archipelago » qemu

/*

 * Copyright (c) 2007, Intel Corporation.

 *

 * This work is licensed under the terms of the GNU GPL, version 2.  See

 * the COPYING file in the top-level directory.

 *

 * Jiang Yunhong <yunhong.jiang@intel.com>

 *

 * This file implements direct PCI assignment to a HVM guest

 */

#include <sys/mman.h>

#include "xen_backend.h"

#include "xen_pt.h"

#include "apic-msidef.h"

#define XEN_PT_AUTO_ASSIGN -1

/* shift count for gflags */

#define XEN_PT_GFLAGS_SHIFT_DEST_ID        0

#define XEN_PT_GFLAGS_SHIFT_RH             8

#define XEN_PT_GFLAGS_SHIFT_DM             9

#define XEN_PT_GFLAGSSHIFT_DELIV_MODE     12

#define XEN_PT_GFLAGSSHIFT_TRG_MODE       15

/*

 * Helpers

 */

static inline uint8_t msi_vector(uint32_t data)

{

    return (data & MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;

}

static inline uint8_t msi_dest_id(uint32_t addr)

{

    return (addr & MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;

}

static inline uint32_t msi_ext_dest_id(uint32_t addr_hi)

{

    return addr_hi & 0xffffff00;

}

static uint32_t msi_gflags(uint32_t data, uint64_t addr)

{

    uint32_t result = 0;

    int rh, dm, dest_id, deliv_mode, trig_mode;

    rh = (addr >> MSI_ADDR_REDIRECTION_SHIFT) & 0x1;

    dm = (addr >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;

    dest_id = msi_dest_id(addr);

    deliv_mode = (data >> MSI_DATA_DELIVERY_MODE_SHIFT) & 0x7;

    trig_mode = (data >> MSI_DATA_TRIGGER_SHIFT) & 0x1;

    result = dest_id | (rh << XEN_PT_GFLAGS_SHIFT_RH)

        | (dm << XEN_PT_GFLAGS_SHIFT_DM)

        | (deliv_mode << XEN_PT_GFLAGSSHIFT_DELIV_MODE)

        | (trig_mode << XEN_PT_GFLAGSSHIFT_TRG_MODE);

    return result;

}

static inline uint64_t msi_addr64(XenPTMSI *msi)

{

    return (uint64_t)msi->addr_hi << 32 | msi->addr_lo;

}

static int msi_msix_enable(XenPCIPassthroughState *s,

                           uint32_t address,

                           uint16_t flag,

                           bool enable)

{

    uint16_t val = 0;

    if (!address) {

        return -1;

    }

    xen_host_pci_get_word(&s->real_device, address, &val);

    if (enable) {

        val |= flag;

    } else {

        val &= ~flag;

    }

    xen_host_pci_set_word(&s->real_device, address, val);

    return 0;

}

static int msi_msix_setup(XenPCIPassthroughState *s,

                          uint64_t addr,

                          uint32_t data,

                          int *ppirq,

                          bool is_msix,

                          int msix_entry,

                          bool is_not_mapped)

{

    uint8_t gvec = msi_vector(data);

    int rc = 0;

    assert((!is_msix && msix_entry == 0) || is_msix);

    if (gvec == 0) {

        /* if gvec is 0, the guest is asking for a particular pirq that

         * is passed as dest_id */

        *ppirq = msi_ext_dest_id(addr >> 32) | msi_dest_id(addr);

        if (!*ppirq) {

            /* this probably identifies an misconfiguration of the guest,

             * try the emulated path */

            *ppirq = XEN_PT_UNASSIGNED_PIRQ;

        } else {

            XEN_PT_LOG(&s->dev, "requested pirq %d for MSI%s"

                       " (vec: %#x, entry: %#x)\n",

                       *ppirq, is_msix ? "-X" : "", gvec, msix_entry);

        }

    }

    if (is_not_mapped) {

        uint64_t table_base = 0;

        if (is_msix) {

            table_base = s->msix->table_base;

        }

        rc = xc_physdev_map_pirq_msi(xen_xc, xen_domid, XEN_PT_AUTO_ASSIGN,

                                     ppirq, PCI_DEVFN(s->real_device.dev,

                                                      s->real_device.func),

                                     s->real_device.bus,

                                     msix_entry, table_base);

        if (rc) {

            XEN_PT_ERR(&s->dev,

                       "Mapping of MSI%s (rc: %i, vec: %#x, entry %#x)\n",

                       is_msix ? "-X" : "", rc, gvec, msix_entry);

            return rc;

        }

    }

    return 0;

}

static int msi_msix_update(XenPCIPassthroughState *s,

                           uint64_t addr,

                           uint32_t data,

                           int pirq,

                           bool is_msix,

                           int msix_entry,

                           int *old_pirq)

{

    PCIDevice *d = &s->dev;

    uint8_t gvec = msi_vector(data);

    uint32_t gflags = msi_gflags(data, addr);

    int rc = 0;

    uint64_t table_addr = 0;

    XEN_PT_LOG(d, "Updating MSI%s with pirq %d gvec %#x gflags %#x"

               " (entry: %#x)\n",

               is_msix ? "-X" : "", pirq, gvec, gflags, msix_entry);

    if (is_msix) {

        table_addr = s->msix->mmio_base_addr;

    }

    rc = xc_domain_update_msi_irq(xen_xc, xen_domid, gvec,

                                  pirq, gflags, table_addr);

    if (rc) {

        XEN_PT_ERR(d, "Updating of MSI%s failed. (rc: %d)\n",

                   is_msix ? "-X" : "", rc);

        if (xc_physdev_unmap_pirq(xen_xc, xen_domid, *old_pirq)) {

            XEN_PT_ERR(d, "Unmapping of MSI%s pirq %d failed.\n",

                       is_msix ? "-X" : "", *old_pirq);

        }

        *old_pirq = XEN_PT_UNASSIGNED_PIRQ;

    }

    return rc;

}

static int msi_msix_disable(XenPCIPassthroughState *s,

                            uint64_t addr,

                            uint32_t data,

                            int pirq,

                            bool is_msix,

                            bool is_binded)

{

    PCIDevice *d = &s->dev;

    uint8_t gvec = msi_vector(data);

    uint32_t gflags = msi_gflags(data, addr);

    int rc = 0;

    if (pirq == XEN_PT_UNASSIGNED_PIRQ) {

        return 0;

    }

    if (is_binded) {

        XEN_PT_LOG(d, "Unbind MSI%s with pirq %d, gvec %#x\n",

                   is_msix ? "-X" : "", pirq, gvec);

        rc = xc_domain_unbind_msi_irq(xen_xc, xen_domid, gvec, pirq, gflags);

        if (rc) {

            XEN_PT_ERR(d, "Unbinding of MSI%s failed. (pirq: %d, gvec: %#x)\n",

                       is_msix ? "-X" : "", pirq, gvec);

            return rc;

        }

    }

    XEN_PT_LOG(d, "Unmap MSI%s pirq %d\n", is_msix ? "-X" : "", pirq);

    rc = xc_physdev_unmap_pirq(xen_xc, xen_domid, pirq);

    if (rc) {

        XEN_PT_ERR(d, "Unmapping of MSI%s pirq %d failed. (rc: %i)\n",

                   is_msix ? "-X" : "", pirq, rc);

        return rc;

    }

    return 0;

}

/*

 * MSI virtualization functions

 */

int xen_pt_msi_set_enable(XenPCIPassthroughState *s, bool enable)

{

    XEN_PT_LOG(&s->dev, "%s MSI.\n", enable ? "enabling" : "disabling");

    if (!s->msi) {

        return -1;

    }

    return msi_msix_enable(s, s->msi->ctrl_offset, PCI_MSI_FLAGS_ENABLE,

                           enable);

}

/* setup physical msi, but don't enable it */

int xen_pt_msi_setup(XenPCIPassthroughState *s)

{

    int pirq = XEN_PT_UNASSIGNED_PIRQ;

    int rc = 0;

    XenPTMSI *msi = s->msi;

    if (msi->initialized) {

        XEN_PT_ERR(&s->dev,

                   "Setup physical MSI when it has been properly initialized.\n");

        return -1;

    }

    rc = msi_msix_setup(s, msi_addr64(msi), msi->data, &pirq, false, 0, true);

    if (rc) {

        return rc;

    }

    if (pirq < 0) {

        XEN_PT_ERR(&s->dev, "Invalid pirq number: %d.\n", pirq);

        return -1;

    }

    msi->pirq = pirq;

    XEN_PT_LOG(&s->dev, "MSI mapped with pirq %d.\n", pirq);

    return 0;

}

int xen_pt_msi_update(XenPCIPassthroughState *s)

{

    XenPTMSI *msi = s->msi;

    return msi_msix_update(s, msi_addr64(msi), msi->data, msi->pirq,

                           false, 0, &msi->pirq);

}

void xen_pt_msi_disable(XenPCIPassthroughState *s)

{

    XenPTMSI *msi = s->msi;

    if (!msi) {

        return;

    }

    xen_pt_msi_set_enable(s, false);

    msi_msix_disable(s, msi_addr64(msi), msi->data, msi->pirq, false,

                     msi->initialized);

    /* clear msi info */

    msi->flags = 0;

    msi->mapped = false;

    msi->pirq = XEN_PT_UNASSIGNED_PIRQ;

}

/*

 * MSI-X virtualization functions

 */

static int msix_set_enable(XenPCIPassthroughState *s, bool enabled)

{

    XEN_PT_LOG(&s->dev, "%s MSI-X.\n", enabled ? "enabling" : "disabling");

    if (!s->msix) {

        return -1;

    }

    return msi_msix_enable(s, s->msix->ctrl_offset, PCI_MSIX_FLAGS_ENABLE,

                           enabled);

}

static int xen_pt_msix_update_one(XenPCIPassthroughState *s, int entry_nr)

{

    XenPTMSIXEntry *entry = NULL;

    int pirq;

    int rc;

    if (entry_nr < 0 || entry_nr >= s->msix->total_entries) {

        return -EINVAL;

    }

    entry = &s->msix->msix_entry[entry_nr];

    if (!entry->updated) {

        return 0;

    }

    pirq = entry->pirq;

    rc = msi_msix_setup(s, entry->addr, entry->data, &pirq, true, entry_nr,

                        entry->pirq == XEN_PT_UNASSIGNED_PIRQ);

    if (rc) {

        return rc;

    }

    if (entry->pirq == XEN_PT_UNASSIGNED_PIRQ) {

        entry->pirq = pirq;

    }

    rc = msi_msix_update(s, entry->addr, entry->data, pirq, true,

                         entry_nr, &entry->pirq);

    if (!rc) {

        entry->updated = false;

    }

    return rc;

}

int xen_pt_msix_update(XenPCIPassthroughState *s)

{

    XenPTMSIX *msix = s->msix;

    int i;

    for (i = 0; i < msix->total_entries; i++) {

        xen_pt_msix_update_one(s, i);

    }

    return 0;

}

void xen_pt_msix_disable(XenPCIPassthroughState *s)

{

    int i = 0;

    msix_set_enable(s, false);

    for (i = 0; i < s->msix->total_entries; i++) {

        XenPTMSIXEntry *entry = &s->msix->msix_entry[i];

        msi_msix_disable(s, entry->addr, entry->data, entry->pirq, true, true);

        /* clear MSI-X info */

        entry->pirq = XEN_PT_UNASSIGNED_PIRQ;

        entry->updated = false;

    }

}

int xen_pt_msix_update_remap(XenPCIPassthroughState *s, int bar_index)

{

    XenPTMSIXEntry *entry;

    int i, ret;

    if (!(s->msix && s->msix->bar_index == bar_index)) {

        return 0;

    }

    for (i = 0; i < s->msix->total_entries; i++) {

        entry = &s->msix->msix_entry[i];

        if (entry->pirq != XEN_PT_UNASSIGNED_PIRQ) {

            ret = xc_domain_unbind_pt_irq(xen_xc, xen_domid, entry->pirq,

                                          PT_IRQ_TYPE_MSI, 0, 0, 0, 0);

            if (ret) {

                XEN_PT_ERR(&s->dev, "unbind MSI-X entry %d failed\n",

                           entry->pirq);

            }

            entry->updated = true;

        }

    }

    return xen_pt_msix_update(s);

}

static uint32_t get_entry_value(XenPTMSIXEntry *e, int offset)

{

    switch (offset) {

    case PCI_MSIX_ENTRY_LOWER_ADDR:

        return e->addr & UINT32_MAX;

    case PCI_MSIX_ENTRY_UPPER_ADDR:

        return e->addr >> 32;

    case PCI_MSIX_ENTRY_DATA:

        return e->data;

    case PCI_MSIX_ENTRY_VECTOR_CTRL:

        return e->vector_ctrl;

    default:

        return 0;

    }

}

static void set_entry_value(XenPTMSIXEntry *e, int offset, uint32_t val)

{

    switch (offset) {

    case PCI_MSIX_ENTRY_LOWER_ADDR:

        e->addr = (e->addr & ((uint64_t)UINT32_MAX << 32)) | val;

        break;

    case PCI_MSIX_ENTRY_UPPER_ADDR:

        e->addr = (uint64_t)val << 32 | (e->addr & UINT32_MAX);

        break;

    case PCI_MSIX_ENTRY_DATA:

        e->data = val;

        break;

    case PCI_MSIX_ENTRY_VECTOR_CTRL:

        e->vector_ctrl = val;

        break;

    }

}

static void pci_msix_write(void *opaque, hwaddr addr,

                           uint64_t val, unsigned size)

{

    XenPCIPassthroughState *s = opaque;

    XenPTMSIX *msix = s->msix;

    XenPTMSIXEntry *entry;

    int entry_nr, offset;

    entry_nr = addr / PCI_MSIX_ENTRY_SIZE;

    if (entry_nr < 0 || entry_nr >= msix->total_entries) {

        XEN_PT_ERR(&s->dev, "asked MSI-X entry '%i' invalid!\n", entry_nr);

        return;

    }

    entry = &msix->msix_entry[entry_nr];

    offset = addr % PCI_MSIX_ENTRY_SIZE;

    if (offset != PCI_MSIX_ENTRY_VECTOR_CTRL) {

        const volatile uint32_t *vec_ctrl;

        if (get_entry_value(entry, offset) == val) {

            return;

        }

        /*

         * If Xen intercepts the mask bit access, entry->vec_ctrl may not be

         * up-to-date. Read from hardware directly.

         */

        vec_ctrl = s->msix->phys_iomem_base + entry_nr * PCI_MSIX_ENTRY_SIZE

            + PCI_MSIX_ENTRY_VECTOR_CTRL;

        if (msix->enabled && !(*vec_ctrl & PCI_MSIX_ENTRY_CTRL_MASKBIT)) {

            XEN_PT_ERR(&s->dev, "Can't update msix entry %d since MSI-X is"

                       " already enabled.\n", entry_nr);

            return;

        }

        entry->updated = true;

    }

    set_entry_value(entry, offset, val);

    if (offset == PCI_MSIX_ENTRY_VECTOR_CTRL) {

        if (msix->enabled && !(val & PCI_MSIX_ENTRY_CTRL_MASKBIT)) {

            xen_pt_msix_update_one(s, entry_nr);

        }

    }

}

static uint64_t pci_msix_read(void *opaque, hwaddr addr,

                              unsigned size)

{

    XenPCIPassthroughState *s = opaque;

    XenPTMSIX *msix = s->msix;

    int entry_nr, offset;

    entry_nr = addr / PCI_MSIX_ENTRY_SIZE;

    if (entry_nr < 0) {

        XEN_PT_ERR(&s->dev, "asked MSI-X entry '%i' invalid!\n", entry_nr);

        return 0;

    }

    offset = addr % PCI_MSIX_ENTRY_SIZE;

    if (addr < msix->total_entries * PCI_MSIX_ENTRY_SIZE) {

        return get_entry_value(&msix->msix_entry[entry_nr], offset);

    } else {

        /* Pending Bit Array (PBA) */

        return *(uint32_t *)(msix->phys_iomem_base + addr);

    }

}

static const MemoryRegionOps pci_msix_ops = {

    .read = pci_msix_read,

    .write = pci_msix_write,

    .endianness = DEVICE_NATIVE_ENDIAN,

    .valid = {

        .min_access_size = 4,

        .max_access_size = 4,

        .unaligned = false,

    },

};

int xen_pt_msix_init(XenPCIPassthroughState *s, uint32_t base)

{

    uint8_t id = 0;

    uint16_t control = 0;

    uint32_t table_off = 0;

    int i, total_entries, bar_index;

    XenHostPCIDevice *hd = &s->real_device;

    PCIDevice *d = &s->dev;

    int fd = -1;

    XenPTMSIX *msix = NULL;

    int rc = 0;

    rc = xen_host_pci_get_byte(hd, base + PCI_CAP_LIST_ID, &id);

    if (rc) {

        return rc;

    }

    if (id != PCI_CAP_ID_MSIX) {

        XEN_PT_ERR(d, "Invalid id %#x base %#x\n", id, base);

        return -1;

    }

    xen_host_pci_get_word(hd, base + PCI_MSIX_FLAGS, &control);

    total_entries = control & PCI_MSIX_FLAGS_QSIZE;

    total_entries += 1;

    s->msix = g_malloc0(sizeof (XenPTMSIX)

                        + total_entries * sizeof (XenPTMSIXEntry));

    msix = s->msix;

    msix->total_entries = total_entries;

    for (i = 0; i < total_entries; i++) {

        msix->msix_entry[i].pirq = XEN_PT_UNASSIGNED_PIRQ;

    }

    memory_region_init_io(&msix->mmio, &pci_msix_ops, s, "xen-pci-pt-msix",

                          (total_entries * PCI_MSIX_ENTRY_SIZE

                           + XC_PAGE_SIZE - 1)

                          & XC_PAGE_MASK);

    xen_host_pci_get_long(hd, base + PCI_MSIX_TABLE, &table_off);

    bar_index = msix->bar_index = table_off & PCI_MSIX_FLAGS_BIRMASK;

    table_off = table_off & ~PCI_MSIX_FLAGS_BIRMASK;

    msix->table_base = s->real_device.io_regions[bar_index].base_addr;

    XEN_PT_LOG(d, "get MSI-X table BAR base 0x%"PRIx64"\n", msix->table_base);

    fd = open("/dev/mem", O_RDWR);

    if (fd == -1) {

        rc = -errno;

        XEN_PT_ERR(d, "Can't open /dev/mem: %s\n", strerror(errno));

        goto error_out;

    }

    XEN_PT_LOG(d, "table_off = %#x, total_entries = %d\n",

               table_off, total_entries);

    msix->table_offset_adjust = table_off & 0x0fff;

    msix->phys_iomem_base =

        mmap(NULL,

             total_entries * PCI_MSIX_ENTRY_SIZE + msix->table_offset_adjust,

             PROT_READ,

             MAP_SHARED | MAP_LOCKED,

             fd,

             msix->table_base + table_off - msix->table_offset_adjust);

    close(fd);

    if (msix->phys_iomem_base == MAP_FAILED) {

        rc = -errno;

        XEN_PT_ERR(d, "Can't map physical MSI-X table: %s\n", strerror(errno));

        goto error_out;

    }

    msix->phys_iomem_base = (char *)msix->phys_iomem_base

        + msix->table_offset_adjust;

    XEN_PT_LOG(d, "mapping physical MSI-X table to %p\n",

               msix->phys_iomem_base);

    memory_region_add_subregion_overlap(&s->bar[bar_index], table_off,

                                        &msix->mmio,

                                        2); /* Priority: pci default + 1 */

    return 0;

error_out:

    memory_region_destroy(&msix->mmio);

    g_free(s->msix);

    s->msix = NULL;

    return rc;

}

void xen_pt_msix_delete(XenPCIPassthroughState *s)

{

    XenPTMSIX *msix = s->msix;

    if (!msix) {

        return;

    }

    /* unmap the MSI-X memory mapped register area */

    if (msix->phys_iomem_base) {

        XEN_PT_LOG(&s->dev, "unmapping physical MSI-X table from %p\n",

                   msix->phys_iomem_base);

        munmap(msix->phys_iomem_base, msix->total_entries * PCI_MSIX_ENTRY_SIZE

               + msix->table_offset_adjust);

    }

    memory_region_del_subregion(&s->bar[msix->bar_index], &msix->mmio);

    memory_region_destroy(&msix->mmio);

    g_free(s->msix);

    s->msix = NULL;

}