xcom_hcall.c

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/*
 * 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; either version 2 of the License, or
 * (at your option) any 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 *          Tristan Gingold <[email protected]>
 *
 *          Copyright (c) 2007
 *          Isaku Yamahata <yamahata at valinux co jp>
 *                          VA Linux Systems Japan K.K.
 *          consolidate mini and inline version.
 */

#include <linux/module.h>
#include <xen/interface/xen.h>
#include <xen/interface/memory.h>
#include <xen/interface/grant_table.h>
#include <xen/interface/callback.h>
#include <xen/interface/vcpu.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/xencomm.h>

/* Xencomm notes:
 * This file defines hypercalls to be used by xencomm.  The hypercalls simply
 * create inlines or mini descriptors for pointers and then call the raw arch
 * hypercall xencomm_arch_hypercall_XXX
 *
 * If the arch wants to directly use these hypercalls, simply define macros
 * in asm/xen/hypercall.h, eg:
 *  #define HYPERVISOR_sched_op xencomm_hypercall_sched_op
 *
 * The arch may also define HYPERVISOR_xxx as a function and do more operations
 * before/after doing the hypercall.
 *
 * Note: because only inline or mini descriptors are created these functions
 * must only be called with in kernel memory parameters.
 */

int
xencomm_hypercall_console_io(int cmd, int count, char *str)
{
    /* xen early printk uses console io hypercall before
     * xencomm initialization. In that case, we just ignore it.
     */
    if (!xencomm_is_initialized())
        return 0;

    return xencomm_arch_hypercall_console_io
        (cmd, count, xencomm_map_no_alloc(str, count));
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_console_io);

int
xencomm_hypercall_event_channel_op(int cmd, void *op)
{
    struct xencomm_handle *desc;
    desc = xencomm_map_no_alloc(op, sizeof(struct evtchn_op));
    if (desc == NULL)
        return -EINVAL;

    return xencomm_arch_hypercall_event_channel_op(cmd, desc);
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_event_channel_op);

int
xencomm_hypercall_xen_version(int cmd, void *arg)
{
    struct xencomm_handle *desc;
    unsigned int argsize;

    switch (cmd) {
    case XENVER_version:
        /* do not actually pass an argument */
        return xencomm_arch_hypercall_xen_version(cmd, 0);
    case XENVER_extraversion:
        argsize = sizeof(struct xen_extraversion);
        break;
    case XENVER_compile_info:
        argsize = sizeof(struct xen_compile_info);
        break;
    case XENVER_capabilities:
        argsize = sizeof(struct xen_capabilities_info);
        break;
    case XENVER_changeset:
        argsize = sizeof(struct xen_changeset_info);
        break;
    case XENVER_platform_parameters:
        argsize = sizeof(struct xen_platform_parameters);
        break;
    case XENVER_get_features:
        argsize = (arg == NULL) ? 0 : sizeof(struct xen_feature_info);
        break;

    default:
        printk(KERN_DEBUG
               "%s: unknown version op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    desc = xencomm_map_no_alloc(arg, argsize);
    if (desc == NULL)
        return -EINVAL;

    return xencomm_arch_hypercall_xen_version(cmd, desc);
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_xen_version);

int
xencomm_hypercall_physdev_op(int cmd, void *op)
{
    unsigned int argsize;

    switch (cmd) {
    case PHYSDEVOP_apic_read:
    case PHYSDEVOP_apic_write:
        argsize = sizeof(struct physdev_apic);
        break;
    case PHYSDEVOP_alloc_irq_vector:
    case PHYSDEVOP_free_irq_vector:
        argsize = sizeof(struct physdev_irq);
        break;
    case PHYSDEVOP_irq_status_query:
        argsize = sizeof(struct physdev_irq_status_query);
        break;

    default:
        printk(KERN_DEBUG
               "%s: unknown physdev op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    return xencomm_arch_hypercall_physdev_op
        (cmd, xencomm_map_no_alloc(op, argsize));
}

static int
xencommize_grant_table_op(struct xencomm_mini **xc_area,
              unsigned int cmd, void *op, unsigned int count,
              struct xencomm_handle **desc)
{
    struct xencomm_handle *desc1;
    unsigned int argsize;

    switch (cmd) {
    case GNTTABOP_map_grant_ref:
        argsize = sizeof(struct gnttab_map_grant_ref);
        break;
    case GNTTABOP_unmap_grant_ref:
        argsize = sizeof(struct gnttab_unmap_grant_ref);
        break;
    case GNTTABOP_setup_table:
    {
        struct gnttab_setup_table *setup = op;

        argsize = sizeof(*setup);

        if (count != 1)
            return -EINVAL;
        desc1 = __xencomm_map_no_alloc
            (xen_guest_handle(setup->frame_list),
             setup->nr_frames *
             sizeof(*xen_guest_handle(setup->frame_list)),
             *xc_area);
        if (desc1 == NULL)
            return -EINVAL;
        (*xc_area)++;
        set_xen_guest_handle(setup->frame_list, (void *)desc1);
        break;
    }
    case GNTTABOP_dump_table:
        argsize = sizeof(struct gnttab_dump_table);
        break;
    case GNTTABOP_transfer:
        argsize = sizeof(struct gnttab_transfer);
        break;
    case GNTTABOP_copy:
        argsize = sizeof(struct gnttab_copy);
        break;
    case GNTTABOP_query_size:
        argsize = sizeof(struct gnttab_query_size);
        break;
    default:
        printk(KERN_DEBUG "%s: unknown hypercall grant table op %d\n",
               __func__, cmd);
        BUG();
    }

    *desc = __xencomm_map_no_alloc(op, count * argsize, *xc_area);
    if (*desc == NULL)
        return -EINVAL;
    (*xc_area)++;

    return 0;
}

int
xencomm_hypercall_grant_table_op(unsigned int cmd, void *op,
                 unsigned int count)
{
    int rc;
    struct xencomm_handle *desc;
    XENCOMM_MINI_ALIGNED(xc_area, 2);

    rc = xencommize_grant_table_op(&xc_area, cmd, op, count, &desc);
    if (rc)
        return rc;

    return xencomm_arch_hypercall_grant_table_op(cmd, desc, count);
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_grant_table_op);

int
xencomm_hypercall_sched_op(int cmd, void *arg)
{
    struct xencomm_handle *desc;
    unsigned int argsize;

    switch (cmd) {
    case SCHEDOP_yield:
    case SCHEDOP_block:
        argsize = 0;
        break;
    case SCHEDOP_shutdown:
        argsize = sizeof(struct sched_shutdown);
        break;
    case SCHEDOP_poll:
    {
        struct sched_poll *poll = arg;
        struct xencomm_handle *ports;

        argsize = sizeof(struct sched_poll);
        ports = xencomm_map_no_alloc(xen_guest_handle(poll->ports),
                     sizeof(*xen_guest_handle(poll->ports)));

        set_xen_guest_handle(poll->ports, (void *)ports);
        break;
    }
    default:
        printk(KERN_DEBUG "%s: unknown sched op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    desc = xencomm_map_no_alloc(arg, argsize);
    if (desc == NULL)
        return -EINVAL;

    return xencomm_arch_hypercall_sched_op(cmd, desc);
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_sched_op);

int
xencomm_hypercall_multicall(void *call_list, int nr_calls)
{
    int rc;
    int i;
    struct multicall_entry *mce;
    struct xencomm_handle *desc;
    XENCOMM_MINI_ALIGNED(xc_area, nr_calls * 2);

    for (i = 0; i < nr_calls; i++) {
        mce = (struct multicall_entry *)call_list + i;

        switch (mce->op) {
        case __HYPERVISOR_update_va_mapping:
        case __HYPERVISOR_mmu_update:
            /* No-op on ia64.  */
            break;
        case __HYPERVISOR_grant_table_op:
            rc = xencommize_grant_table_op
                (&xc_area,
                 mce->args[0], (void *)mce->args[1],
                 mce->args[2], &desc);
            if (rc)
                return rc;
            mce->args[1] = (unsigned long)desc;
            break;
        case __HYPERVISOR_memory_op:
        default:
            printk(KERN_DEBUG
                   "%s: unhandled multicall op entry op %lu\n",
                   __func__, mce->op);
            return -ENOSYS;
        }
    }

    desc = xencomm_map_no_alloc(call_list,
                    nr_calls * sizeof(struct multicall_entry));
    if (desc == NULL)
        return -EINVAL;

    return xencomm_arch_hypercall_multicall(desc, nr_calls);
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_multicall);

int
xencomm_hypercall_callback_op(int cmd, void *arg)
{
    unsigned int argsize;
    switch (cmd) {
    case CALLBACKOP_register:
        argsize = sizeof(struct callback_register);
        break;
    case CALLBACKOP_unregister:
        argsize = sizeof(struct callback_unregister);
        break;
    default:
        printk(KERN_DEBUG
               "%s: unknown callback op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    return xencomm_arch_hypercall_callback_op
        (cmd, xencomm_map_no_alloc(arg, argsize));
}

static int
xencommize_memory_reservation(struct xencomm_mini *xc_area,
                  struct xen_memory_reservation *mop)
{
    struct xencomm_handle *desc;

    desc = __xencomm_map_no_alloc(xen_guest_handle(mop->extent_start),
            mop->nr_extents *
            sizeof(*xen_guest_handle(mop->extent_start)),
            xc_area);
    if (desc == NULL)
        return -EINVAL;

    set_xen_guest_handle(mop->extent_start, (void *)desc);
    return 0;
}

int
xencomm_hypercall_memory_op(unsigned int cmd, void *arg)
{
    GUEST_HANDLE(xen_pfn_t) extent_start_va[2] = { {NULL}, {NULL} };
    struct xen_memory_reservation *xmr = NULL;
    int rc;
    struct xencomm_handle *desc;
    unsigned int argsize;
    XENCOMM_MINI_ALIGNED(xc_area, 2);

    switch (cmd) {
    case XENMEM_increase_reservation:
    case XENMEM_decrease_reservation:
    case XENMEM_populate_physmap:
        xmr = (struct xen_memory_reservation *)arg;
        set_xen_guest_handle(extent_start_va[0],
                     xen_guest_handle(xmr->extent_start));

        argsize = sizeof(*xmr);
        rc = xencommize_memory_reservation(xc_area, xmr);
        if (rc)
            return rc;
        xc_area++;
        break;

    case XENMEM_maximum_ram_page:
        argsize = 0;
        break;

    case XENMEM_add_to_physmap:
        argsize = sizeof(struct xen_add_to_physmap);
        break;

    default:
        printk(KERN_DEBUG "%s: unknown memory op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    desc = xencomm_map_no_alloc(arg, argsize);
    if (desc == NULL)
        return -EINVAL;

    rc = xencomm_arch_hypercall_memory_op(cmd, desc);

    switch (cmd) {
    case XENMEM_increase_reservation:
    case XENMEM_decrease_reservation:
    case XENMEM_populate_physmap:
        set_xen_guest_handle(xmr->extent_start,
                     xen_guest_handle(extent_start_va[0]));
        break;
    }

    return rc;
}
EXPORT_SYMBOL_GPL(xencomm_hypercall_memory_op);

int
xencomm_hypercall_suspend(unsigned long srec)
{
    struct sched_shutdown arg;

    arg.reason = SHUTDOWN_suspend;

    return xencomm_arch_hypercall_sched_op(
        SCHEDOP_shutdown, xencomm_map_no_alloc(&arg, sizeof(arg)));
}

long
xencomm_hypercall_vcpu_op(int cmd, int cpu, void *arg)
{
    unsigned int argsize;
    switch (cmd) {
    case VCPUOP_register_runstate_memory_area: {
        struct vcpu_register_runstate_memory_area *area =
            (struct vcpu_register_runstate_memory_area *)arg;
        argsize = sizeof(*arg);
        set_xen_guest_handle(area->addr.h,
             (void *)xencomm_map_no_alloc(area->addr.v,
                          sizeof(area->addr.v)));
        break;
    }

    default:
        printk(KERN_DEBUG "%s: unknown vcpu op %d\n", __func__, cmd);
        return -ENOSYS;
    }

    return xencomm_arch_hypercall_vcpu_op(cmd, cpu,
                    xencomm_map_no_alloc(arg, argsize));
}

long
xencomm_hypercall_opt_feature(void *arg)
{
    return xencomm_arch_hypercall_opt_feature(
        xencomm_map_no_alloc(arg,
                     sizeof(struct xen_ia64_opt_feature)));
}