VMCI: guest side driver implementation.

VMCI guest side driver code implementation.

Signed-off-by: George Zhang <georgezhang@vmware.com>
Acked-by: Andy king <acking@vmware.com>
Acked-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 759 insertions, 0 deletions

diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c
new file mode 100644
index 000000000000..d302c89d2bfa
--- /dev/null
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -0,0 +1,759 @@
+/*
+ * VMware VMCI Driver
+ *
+ * Copyright (C) 2012 VMware, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation version 2 and no later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include <linux/vmw_vmci_defs.h>
+#include <linux/vmw_vmci_api.h>
+#include <linux/moduleparam.h>
+#include <linux/interrupt.h>
+#include <linux/highmem.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include "vmci_datagram.h"
+#include "vmci_doorbell.h"
+#include "vmci_context.h"
+#include "vmci_driver.h"
+#include "vmci_event.h"
+
+#define PCI_VENDOR_ID_VMWARE            0x15AD
+#define PCI_DEVICE_ID_VMWARE_VMCI       0x0740
+
+#define VMCI_UTIL_NUM_RESOURCES 1
+
+static bool vmci_disable_msi;
+module_param_named(disable_msi, vmci_disable_msi, bool, 0);
+MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
+
+static bool vmci_disable_msix;
+module_param_named(disable_msix, vmci_disable_msix, bool, 0);
+MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
+
+static u32 ctx_update_sub_id = VMCI_INVALID_ID;
+static u32 vm_context_id = VMCI_INVALID_ID;
+
+struct vmci_guest_device {
+        struct device *dev;     /* PCI device we are attached to */
+        void __iomem *iobase;
+
+        unsigned int irq;
+        unsigned int intr_type;
+        bool exclusive_vectors;
+        struct msix_entry msix_entries[VMCI_MAX_INTRS];
+
+        struct tasklet_struct datagram_tasklet;
+        struct tasklet_struct bm_tasklet;
+
+        void *data_buffer;
+        void *notification_bitmap;
+};
+
+/* vmci_dev singleton device and supporting data*/
+static struct vmci_guest_device *vmci_dev_g;
+static DEFINE_SPINLOCK(vmci_dev_spinlock);
+
+static atomic_t vmci_num_guest_devices = ATOMIC_INIT(0);
+
+bool vmci_guest_code_active(void)
+{
+        return atomic_read(&vmci_num_guest_devices) != 0;
+}
+
+u32 vmci_get_vm_context_id(void)
+{
+        if (vm_context_id == VMCI_INVALID_ID) {
+                u32 result;
+                struct vmci_datagram get_cid_msg;
+                get_cid_msg.dst =
+                    vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
+                                     VMCI_GET_CONTEXT_ID);
+                get_cid_msg.src = VMCI_ANON_SRC_HANDLE;
+                get_cid_msg.payload_size = 0;
+                result = vmci_send_datagram(&get_cid_msg);
+                if (result >= 0)
+                        vm_context_id = result;
+        }
+        return vm_context_id;
+}
+
+/*
+ * VM to hypervisor call mechanism. We use the standard VMware naming
+ * convention since shared code is calling this function as well.
+ */
+int vmci_send_datagram(struct vmci_datagram *dg)
+{
+        unsigned long flags;
+        int result;
+
+        /* Check args. */
+        if (dg == NULL)
+                return VMCI_ERROR_INVALID_ARGS;
+
+        /*
+         * Need to acquire spinlock on the device because the datagram
+         * data may be spread over multiple pages and the monitor may
+         * interleave device user rpc calls from multiple
+         * VCPUs. Acquiring the spinlock precludes that
+         * possibility. Disabling interrupts to avoid incoming
+         * datagrams during a "rep out" and possibly landing up in
+         * this function.
+         */
+        spin_lock_irqsave(&vmci_dev_spinlock, flags);
+
+        if (vmci_dev_g) {
+                iowrite8_rep(vmci_dev_g->iobase + VMCI_DATA_OUT_ADDR,
+                             dg, VMCI_DG_SIZE(dg));
+                result = ioread32(vmci_dev_g->iobase + VMCI_RESULT_LOW_ADDR);
+        } else {
+                result = VMCI_ERROR_UNAVAILABLE;
+        }
+
+        spin_unlock_irqrestore(&vmci_dev_spinlock, flags);
+
+        return result;
+}
+EXPORT_SYMBOL_GPL(vmci_send_datagram);
+
+/*
+ * Gets called with the new context id if updated or resumed.
+ * Context id.
+ */
+static void vmci_guest_cid_update(u32 sub_id,
+                                  const struct vmci_event_data *event_data,
+                                  void *client_data)
+{
+        const struct vmci_event_payld_ctx *ev_payload =
+                                vmci_event_data_const_payload(event_data);
+
+        if (sub_id != ctx_update_sub_id) {
+                pr_devel("Invalid subscriber (ID=0x%x)\n", sub_id);
+                return;
+        }
+
+        if (!event_data || ev_payload->context_id == VMCI_INVALID_ID) {
+                pr_devel("Invalid event data\n");
+                return;
+        }
+
+        pr_devel("Updating context from (ID=0x%x) to (ID=0x%x) on event (type=%d)\n",
+                 vm_context_id, ev_payload->context_id, event_data->event);
+
+        vm_context_id = ev_payload->context_id;
+}
+
+/*
+ * Verify that the host supports the hypercalls we need. If it does not,
+ * try to find fallback hypercalls and use those instead.  Returns
+ * true if required hypercalls (or fallback hypercalls) are
+ * supported by the host, false otherwise.
+ */
+static bool vmci_check_host_caps(struct pci_dev *pdev)
+{
+        bool result;
+        struct vmci_resource_query_msg *msg;
+        u32 msg_size = sizeof(struct vmci_resource_query_hdr) +
+                                VMCI_UTIL_NUM_RESOURCES * sizeof(u32);
+        struct vmci_datagram *check_msg;
+
+        check_msg = kmalloc(msg_size, GFP_KERNEL);
+        if (!check_msg) {
+                dev_err(&pdev->dev, "%s: Insufficient memory\n", __func__);
+                return false;
+        }
+
+        check_msg->dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
+                                          VMCI_RESOURCES_QUERY);
+        check_msg->src = VMCI_ANON_SRC_HANDLE;
+        check_msg->payload_size = msg_size - VMCI_DG_HEADERSIZE;
+        msg = (struct vmci_resource_query_msg *)VMCI_DG_PAYLOAD(check_msg);
+
+        msg->num_resources = VMCI_UTIL_NUM_RESOURCES;
+        msg->resources[0] = VMCI_GET_CONTEXT_ID;
+
+        /* Checks that hyper calls are supported */
+        result = vmci_send_datagram(check_msg) == 0x01;
+        kfree(check_msg);
+
+        dev_dbg(&pdev->dev, "%s: Host capability check: %s\n",
+                __func__, result ? "PASSED" : "FAILED");
+
+        /* We need the vector. There are no fallbacks. */
+        return result;
+}
+
+/*
+ * Reads datagrams from the data in port and dispatches them. We
+ * always start reading datagrams into only the first page of the
+ * datagram buffer. If the datagrams don't fit into one page, we
+ * use the maximum datagram buffer size for the remainder of the
+ * invocation. This is a simple heuristic for not penalizing
+ * small datagrams.
+ *
+ * This function assumes that it has exclusive access to the data
+ * in port for the duration of the call.
+ */
+static void vmci_dispatch_dgs(unsigned long data)
+{
+        struct vmci_guest_device *vmci_dev = (struct vmci_guest_device *)data;
+        u8 *dg_in_buffer = vmci_dev->data_buffer;
+        struct vmci_datagram *dg;
+        size_t dg_in_buffer_size = VMCI_MAX_DG_SIZE;
+        size_t current_dg_in_buffer_size = PAGE_SIZE;
+        size_t remaining_bytes;
+
+        BUILD_BUG_ON(VMCI_MAX_DG_SIZE < PAGE_SIZE);
+
+        ioread8_rep(vmci_dev->iobase + VMCI_DATA_IN_ADDR,
+                    vmci_dev->data_buffer, current_dg_in_buffer_size);
+        dg = (struct vmci_datagram *)dg_in_buffer;
+        remaining_bytes = current_dg_in_buffer_size;
+
+        while (dg->dst.resource != VMCI_INVALID_ID ||
+               remaining_bytes > PAGE_SIZE) {
+                unsigned dg_in_size;
+
+                /*
+                 * When the input buffer spans multiple pages, a datagram can
+                 * start on any page boundary in the buffer.
+                 */
+                if (dg->dst.resource == VMCI_INVALID_ID) {
+                        dg = (struct vmci_datagram *)roundup(
+                                (uintptr_t)dg + 1, PAGE_SIZE);
+                        remaining_bytes =
+                                (size_t)(dg_in_buffer +
+                                         current_dg_in_buffer_size -
+                                         (u8 *)dg);
+                        continue;
+                }
+
+                dg_in_size = VMCI_DG_SIZE_ALIGNED(dg);
+
+                if (dg_in_size <= dg_in_buffer_size) {
+                        int result;
+
+                        /*
+                         * If the remaining bytes in the datagram
+                         * buffer doesn't contain the complete
+                         * datagram, we first make sure we have enough
+                         * room for it and then we read the reminder
+                         * of the datagram and possibly any following
+                         * datagrams.
+                         */
+                        if (dg_in_size > remaining_bytes) {
+                                if (remaining_bytes !=
+                                    current_dg_in_buffer_size) {
+
+                                        /*
+                                         * We move the partial
+                                         * datagram to the front and
+                                         * read the reminder of the
+                                         * datagram and possibly
+                                         * following calls into the
+                                         * following bytes.
+                                         */
+                                        memmove(dg_in_buffer, dg_in_buffer +
+                                                current_dg_in_buffer_size -
+                                                remaining_bytes,
+                                                remaining_bytes);
+                                        dg = (struct vmci_datagram *)
+                                            dg_in_buffer;
+                                }
+
+                                if (current_dg_in_buffer_size !=
+                                    dg_in_buffer_size)
+                                        current_dg_in_buffer_size =
+                                            dg_in_buffer_size;
+
+                                ioread8_rep(vmci_dev->iobase +
+                                                VMCI_DATA_IN_ADDR,
+                                        vmci_dev->data_buffer +
+                                                remaining_bytes,
+                                        current_dg_in_buffer_size -
+                                                remaining_bytes);
+                        }
+
+                        /*
+                         * We special case event datagrams from the
+                         * hypervisor.
+                         */
+                        if (dg->src.context == VMCI_HYPERVISOR_CONTEXT_ID &&
+                            dg->dst.resource == VMCI_EVENT_HANDLER) {
+                                result = vmci_event_dispatch(dg);
+                        } else {
+                                result = vmci_datagram_invoke_guest_handler(dg);
+                        }
+                        if (result < VMCI_SUCCESS)
+                                dev_dbg(vmci_dev->dev,
+                                        "Datagram with resource (ID=0x%x) failed (err=%d)\n",
+                                         dg->dst.resource, result);
+
+                        /* On to the next datagram. */
+                        dg = (struct vmci_datagram *)((u8 *)dg +
+                                                      dg_in_size);
+                } else {
+                        size_t bytes_to_skip;
+
+                        /*
+                         * Datagram doesn't fit in datagram buffer of maximal
+                         * size. We drop it.
+                         */
+                        dev_dbg(vmci_dev->dev,
+                                "Failed to receive datagram (size=%u bytes)\n",
+                                 dg_in_size);
+
+                        bytes_to_skip = dg_in_size - remaining_bytes;
+                        if (current_dg_in_buffer_size != dg_in_buffer_size)
+                                current_dg_in_buffer_size = dg_in_buffer_size;
+
+                        for (;;) {
+                                ioread8_rep(vmci_dev->iobase +
+                                                VMCI_DATA_IN_ADDR,
+                                        vmci_dev->data_buffer,
+                                        current_dg_in_buffer_size);
+                                if (bytes_to_skip <= current_dg_in_buffer_size)
+                                        break;
+
+                                bytes_to_skip -= current_dg_in_buffer_size;
+                        }
+                        dg = (struct vmci_datagram *)(dg_in_buffer +
+                                                      bytes_to_skip);
+                }
+
+                remaining_bytes =
+                    (size_t) (dg_in_buffer + current_dg_in_buffer_size -
+                              (u8 *)dg);
+
+                if (remaining_bytes < VMCI_DG_HEADERSIZE) {
+                        /* Get the next batch of datagrams. */
+
+                        ioread8_rep(vmci_dev->iobase + VMCI_DATA_IN_ADDR,
+                                    vmci_dev->data_buffer,
+                                    current_dg_in_buffer_size);
+                        dg = (struct vmci_datagram *)dg_in_buffer;
+                        remaining_bytes = current_dg_in_buffer_size;
+                }
+        }
+}
+
+/*
+ * Scans the notification bitmap for raised flags, clears them
+ * and handles the notifications.
+ */
+static void vmci_process_bitmap(unsigned long data)
+{
+        struct vmci_guest_device *dev = (struct vmci_guest_device *)data;
+
+        if (!dev->notification_bitmap) {
+                dev_dbg(dev->dev, "No bitmap present in %s\n", __func__);
+                return;
+        }
+
+        vmci_dbell_scan_notification_entries(dev->notification_bitmap);
+}
+
+/*
+ * Enable MSI-X.  Try exclusive vectors first, then shared vectors.
+ */
+static int vmci_enable_msix(struct pci_dev *pdev,
+                            struct vmci_guest_device *vmci_dev)
+{
+        int i;
+        int result;
+
+        for (i = 0; i < VMCI_MAX_INTRS; ++i) {
+                vmci_dev->msix_entries[i].entry = i;
+                vmci_dev->msix_entries[i].vector = i;
+        }
+
+        result = pci_enable_msix(pdev, vmci_dev->msix_entries, VMCI_MAX_INTRS);
+        if (result == 0)
+                vmci_dev->exclusive_vectors = true;
+        else if (result > 0)
+                result = pci_enable_msix(pdev, vmci_dev->msix_entries, 1);
+
+        return result;
+}
+
+/*
+ * Interrupt handler for legacy or MSI interrupt, or for first MSI-X
+ * interrupt (vector VMCI_INTR_DATAGRAM).
+ */
+static irqreturn_t vmci_interrupt(int irq, void *_dev)
+{
+        struct vmci_guest_device *dev = _dev;
+
+        /*
+         * If we are using MSI-X with exclusive vectors then we simply schedule
+         * the datagram tasklet, since we know the interrupt was meant for us.
+         * Otherwise we must read the ICR to determine what to do.
+         */
+
+        if (dev->intr_type == VMCI_INTR_TYPE_MSIX && dev->exclusive_vectors) {
+                tasklet_schedule(&dev->datagram_tasklet);
+        } else {
+                unsigned int icr;
+
+                /* Acknowledge interrupt and determine what needs doing. */
+                icr = ioread32(dev->iobase + VMCI_ICR_ADDR);
+                if (icr == 0 || icr == ~0)
+                        return IRQ_NONE;
+
+                if (icr & VMCI_ICR_DATAGRAM) {
+                        tasklet_schedule(&dev->datagram_tasklet);
+                        icr &= ~VMCI_ICR_DATAGRAM;
+                }
+
+                if (icr & VMCI_ICR_NOTIFICATION) {
+                        tasklet_schedule(&dev->bm_tasklet);
+                        icr &= ~VMCI_ICR_NOTIFICATION;
+                }
+
+                if (icr != 0)
+                        dev_warn(dev->dev,
+                                 "Ignoring unknown interrupt cause (%d)\n",
+                                 icr);
+        }
+
+        return IRQ_HANDLED;
+}
+
+/*
+ * Interrupt handler for MSI-X interrupt vector VMCI_INTR_NOTIFICATION,
+ * which is for the notification bitmap.  Will only get called if we are
+ * using MSI-X with exclusive vectors.
+ */
+static irqreturn_t vmci_interrupt_bm(int irq, void *_dev)
+{
+        struct vmci_guest_device *dev = _dev;
+
+        /* For MSI-X we can just assume it was meant for us. */
+        tasklet_schedule(&dev->bm_tasklet);
+
+        return IRQ_HANDLED;
+}
+
+/*
+ * Most of the initialization at module load time is done here.
+ */
+static int vmci_guest_probe_device(struct pci_dev *pdev,
+                                   const struct pci_device_id *id)
+{
+        struct vmci_guest_device *vmci_dev;
+        void __iomem *iobase;
+        unsigned int capabilities;
+        unsigned long cmd;
+        int vmci_err;
+        int error;
+
+        dev_dbg(&pdev->dev, "Probing for vmci/PCI guest device\n");
+
+        error = pcim_enable_device(pdev);
+        if (error) {
+                dev_err(&pdev->dev,
+                        "Failed to enable VMCI device: %d\n", error);
+                return error;
+        }
+
+        error = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
+        if (error) {
+                dev_err(&pdev->dev, "Failed to reserve/map IO regions\n");
+                return error;
+        }
+
+        iobase = pcim_iomap_table(pdev)[0];
+
+        dev_info(&pdev->dev, "Found VMCI PCI device at %#lx, irq %u\n",
+                 (unsigned long)iobase, pdev->irq);
+
+        vmci_dev = devm_kzalloc(&pdev->dev, sizeof(*vmci_dev), GFP_KERNEL);
+        if (!vmci_dev) {
+                dev_err(&pdev->dev,
+                        "Can't allocate memory for VMCI device\n");
+                return -ENOMEM;
+        }
+
+        vmci_dev->dev = &pdev->dev;
+        vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
+        vmci_dev->exclusive_vectors = false;
+        vmci_dev->iobase = iobase;
+
+        tasklet_init(&vmci_dev->datagram_tasklet,
+                     vmci_dispatch_dgs, (unsigned long)vmci_dev);
+        tasklet_init(&vmci_dev->bm_tasklet,
+                     vmci_process_bitmap, (unsigned long)vmci_dev);
+
+        vmci_dev->data_buffer = vmalloc(VMCI_MAX_DG_SIZE);
+        if (!vmci_dev->data_buffer) {
+                dev_err(&pdev->dev,
+                        "Can't allocate memory for datagram buffer\n");
+                return -ENOMEM;
+        }
+
+        pci_set_master(pdev);   /* To enable queue_pair functionality. */
+
+        /*
+         * Verify that the VMCI Device supports the capabilities that
+         * we need. If the device is missing capabilities that we would
+         * like to use, check for fallback capabilities and use those
+         * instead (so we can run a new VM on old hosts). Fail the load if
+         * a required capability is missing and there is no fallback.
+         *
+         * Right now, we need datagrams. There are no fallbacks.
+         */
+        capabilities = ioread32(vmci_dev->iobase + VMCI_CAPS_ADDR);
+        if (!(capabilities & VMCI_CAPS_DATAGRAM)) {
+                dev_err(&pdev->dev, "Device does not support datagrams\n");
+                error = -ENXIO;
+                goto err_free_data_buffer;
+        }
+
+        /*
+         * If the hardware supports notifications, we will use that as
+         * well.
+         */
+        if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
+                vmci_dev->notification_bitmap = vmalloc(PAGE_SIZE);
+                if (!vmci_dev->notification_bitmap) {
+                        dev_warn(&pdev->dev,
+                                 "Unable to allocate notification bitmap\n");
+                } else {
+                        memset(vmci_dev->notification_bitmap, 0, PAGE_SIZE);
+                        capabilities |= VMCI_CAPS_NOTIFICATIONS;
+                }
+        }
+
+        dev_info(&pdev->dev, "Using capabilities 0x%x\n", capabilities);
+
+        /* Let the host know which capabilities we intend to use. */
+        iowrite32(capabilities, vmci_dev->iobase + VMCI_CAPS_ADDR);
+
+        /* Set up global device so that we can start sending datagrams */
+        spin_lock_irq(&vmci_dev_spinlock);
+        vmci_dev_g = vmci_dev;
+        spin_unlock_irq(&vmci_dev_spinlock);
+
+        /*
+         * Register notification bitmap with device if that capability is
+         * used.
+         */
+        if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
+                struct page *page =
+                        vmalloc_to_page(vmci_dev->notification_bitmap);
+                unsigned long bitmap_ppn = page_to_pfn(page);
+                if (!vmci_dbell_register_notification_bitmap(bitmap_ppn)) {
+                        dev_warn(&pdev->dev,
+                                 "VMCI device unable to register notification bitmap with PPN 0x%x\n",
+                                 (u32) bitmap_ppn);
+                        goto err_remove_vmci_dev_g;
+                }
+        }
+
+        /* Check host capabilities. */
+        if (!vmci_check_host_caps(pdev))
+                goto err_remove_bitmap;
+
+        /* Enable device. */
+
+        /*
+         * We subscribe to the VMCI_EVENT_CTX_ID_UPDATE here so we can
+         * update the internal context id when needed.
+         */
+        vmci_err = vmci_event_subscribe(VMCI_EVENT_CTX_ID_UPDATE,
+                                        vmci_guest_cid_update, NULL,
+                                        &ctx_update_sub_id);
+        if (vmci_err < VMCI_SUCCESS)
+                dev_warn(&pdev->dev,
+                         "Failed to subscribe to event (type=%d): %d\n",
+                         VMCI_EVENT_CTX_ID_UPDATE, vmci_err);
+
+        /*
+         * Enable interrupts.  Try MSI-X first, then MSI, and then fallback on
+         * legacy interrupts.
+         */
+        if (!vmci_disable_msix && !vmci_enable_msix(pdev, vmci_dev)) {
+                vmci_dev->intr_type = VMCI_INTR_TYPE_MSIX;
+                vmci_dev->irq = vmci_dev->msix_entries[0].vector;
+        } else if (!vmci_disable_msi && !pci_enable_msi(pdev)) {
+                vmci_dev->intr_type = VMCI_INTR_TYPE_MSI;
+                vmci_dev->irq = pdev->irq;
+        } else {
+                vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
+                vmci_dev->irq = pdev->irq;
+        }
+
+        /*
+         * Request IRQ for legacy or MSI interrupts, or for first
+         * MSI-X vector.
+         */
+        error = request_irq(vmci_dev->irq, vmci_interrupt, IRQF_SHARED,
+                            KBUILD_MODNAME, vmci_dev);
+        if (error) {
+                dev_err(&pdev->dev, "Irq %u in use: %d\n",
+                        vmci_dev->irq, error);
+                goto err_disable_msi;
+        }
+
+        /*
+         * For MSI-X with exclusive vectors we need to request an
+         * interrupt for each vector so that we get a separate
+         * interrupt handler routine.  This allows us to distinguish
+         * between the vectors.
+         */
+        if (vmci_dev->exclusive_vectors) {
+                error = request_irq(vmci_dev->msix_entries[1].vector,
+                                    vmci_interrupt_bm, 0, KBUILD_MODNAME,
+                                    vmci_dev);
+                if (error) {
+                        dev_err(&pdev->dev,
+                                "Failed to allocate irq %u: %d\n",
+                                vmci_dev->msix_entries[1].vector, error);
+                        goto err_free_irq;
+                }
+        }
+
+        dev_dbg(&pdev->dev, "Registered device\n");
+
+        atomic_inc(&vmci_num_guest_devices);
+
+        /* Enable specific interrupt bits. */
+        cmd = VMCI_IMR_DATAGRAM;
+        if (capabilities & VMCI_CAPS_NOTIFICATIONS)
+                cmd |= VMCI_IMR_NOTIFICATION;
+        iowrite32(cmd, vmci_dev->iobase + VMCI_IMR_ADDR);
+
+        /* Enable interrupts. */
+        iowrite32(VMCI_CONTROL_INT_ENABLE,
+                  vmci_dev->iobase + VMCI_CONTROL_ADDR);
+
+        pci_set_drvdata(pdev, vmci_dev);
+        return 0;
+
+err_free_irq:
+        free_irq(vmci_dev->irq, &vmci_dev);
+        tasklet_kill(&vmci_dev->datagram_tasklet);
+        tasklet_kill(&vmci_dev->bm_tasklet);
+
+err_disable_msi:
+        if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX)
+                pci_disable_msix(pdev);
+        else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI)
+                pci_disable_msi(pdev);
+
+        vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
+        if (vmci_err < VMCI_SUCCESS)
+                dev_warn(&pdev->dev,
+                         "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
+                         VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
+
+err_remove_bitmap:
+        if (vmci_dev->notification_bitmap) {
+                iowrite32(VMCI_CONTROL_RESET,
+                          vmci_dev->iobase + VMCI_CONTROL_ADDR);
+                vfree(vmci_dev->notification_bitmap);
+        }
+
+err_remove_vmci_dev_g:
+        spin_lock_irq(&vmci_dev_spinlock);
+        vmci_dev_g = NULL;
+        spin_unlock_irq(&vmci_dev_spinlock);
+
+err_free_data_buffer:
+        vfree(vmci_dev->data_buffer);
+
+        /* The rest are managed resources and will be freed by PCI core */
+        return error;
+}
+
+static void vmci_guest_remove_device(struct pci_dev *pdev)
+{
+        struct vmci_guest_device *vmci_dev = pci_get_drvdata(pdev);
+        int vmci_err;
+
+        dev_dbg(&pdev->dev, "Removing device\n");
+
+        atomic_dec(&vmci_num_guest_devices);
+
+        vmci_qp_guest_endpoints_exit();
+
+        vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
+        if (vmci_err < VMCI_SUCCESS)
+                dev_warn(&pdev->dev,
+                         "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
+                         VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
+
+        spin_lock_irq(&vmci_dev_spinlock);
+        vmci_dev_g = NULL;
+        spin_unlock_irq(&vmci_dev_spinlock);
+
+        dev_dbg(&pdev->dev, "Resetting vmci device\n");
+        iowrite32(VMCI_CONTROL_RESET, vmci_dev->iobase + VMCI_CONTROL_ADDR);
+
+        /*
+         * Free IRQ and then disable MSI/MSI-X as appropriate.  For
+         * MSI-X, we might have multiple vectors, each with their own
+         * IRQ, which we must free too.
+         */
+        free_irq(vmci_dev->irq, vmci_dev);
+        if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX) {
+                if (vmci_dev->exclusive_vectors)
+                        free_irq(vmci_dev->msix_entries[1].vector, vmci_dev);
+                pci_disable_msix(pdev);
+        } else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI) {
+                pci_disable_msi(pdev);
+        }
+
+        tasklet_kill(&vmci_dev->datagram_tasklet);
+        tasklet_kill(&vmci_dev->bm_tasklet);
+
+        if (vmci_dev->notification_bitmap) {
+                /*
+                 * The device reset above cleared the bitmap state of the
+                 * device, so we can safely free it here.
+                 */
+
+                vfree(vmci_dev->notification_bitmap);
+        }
+
+        vfree(vmci_dev->data_buffer);
+
+        /* The rest are managed resources and will be freed by PCI core */
+}
+
+static DEFINE_PCI_DEVICE_TABLE(vmci_ids) = {
+        { PCI_DEVICE(PCI_VENDOR_ID_VMWARE, PCI_DEVICE_ID_VMWARE_VMCI), },
+        { 0 },
+};
+MODULE_DEVICE_TABLE(pci, vmci_ids);
+
+static struct pci_driver vmci_guest_driver = {
+        .name           = KBUILD_MODNAME,
+        .id_table       = vmci_ids,
+        .probe          = vmci_guest_probe_device,
+        .remove         = vmci_guest_remove_device,
+};
+
+int __init vmci_guest_init(void)
+{
+        return pci_register_driver(&vmci_guest_driver);
+}
+
+void __exit vmci_guest_exit(void)
+{
+        pci_unregister_driver(&vmci_guest_driver);
+}