Re: [Qemu-devel] [PATCH 35/38] ivshmem: Clean up after the previous commit

[Marc-André Lureau]

On Mon, Feb 29, 2016 at 7:40 PM, Markus Armbruster <address@hidden> wrote:
> Move code to more sensible places.  Use the opportunity to reorder and
> document IVShmemState members.
>
> Signed-off-by: Markus Armbruster <address@hidden>

Reviewed-by: Marc-André Lureau <address@hidden>


> ---
>  hw/misc/ivshmem.c | 420 
> +++++++++++++++++++++++++++---------------------------
>  1 file changed, 213 insertions(+), 207 deletions(-)
>
> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
> index f7f5b3b..33b6842 100644
> --- a/hw/misc/ivshmem.c
> +++ b/hw/misc/ivshmem.c
> @@ -85,25 +85,30 @@ typedef struct IVShmemState {
>      PCIDevice parent_obj;
>      /*< public >*/
>
> -    HostMemoryBackend *hostmem;
> +    uint32_t features;
> +
> +    /* exactly one of these two may be set */
> +    HostMemoryBackend *hostmem; /* with interrupts */
> +    CharDriverState *server_chr; /* without interrupts */
> +
> +    /* registers */
>      uint32_t intrmask;
>      uint32_t intrstatus;
> +    int vm_id;
>
> -    CharDriverState *server_chr;
> -    MemoryRegion ivshmem_mmio;
> -
> +    /* BARs */
> +    MemoryRegion ivshmem_mmio;  /* BAR 0 (registers) */
>      MemoryRegion *ivshmem_bar2; /* BAR 2 (shared memory) */
>
> +    /* interrupt support */
>      Peer *peers;
>      int nb_peers;               /* space in @peers[] */
> -
> -    int vm_id;
>      uint32_t vectors;
> -    uint32_t features;
>      MSIVector *msi_vectors;
>      uint64_t msg_buf;           /* buffer for receiving server messages */
>      int msg_buffered_bytes;     /* #bytes in @msg_buf */
>
> +    /* migration stuff */
>      OnOffAuto master;
>      Error *migration_blocker;
>
> @@ -812,33 +817,6 @@ static void ivshmem_write_config(PCIDevice *pdev, 
> uint32_t address,
>      }
>  }
>
> -static HostMemoryBackend *desugar_shm(const char *shm, size_t size)
> -{
> -    /* TODO avoid the detour through QemuOpts */
> -    static int counter;
> -    QemuOpts *opts = qemu_opts_create(qemu_find_opts("object"),
> -                                      NULL, 0, &error_abort);
> -    char *path;
> -    Object *obj;
> -
> -    qemu_opt_set(opts, "qom-type", "memory-backend-file",
> -    &error_abort);
> -    /* FIXME need a better way to make up an ID */
> -    qemu_opts_set_id(opts, g_strdup_printf("ivshmem-backend-%d", counter++));
> -    path = g_strdup_printf("/dev/shm/%s", shm);
> -    qemu_opt_set(opts, "mem-path", path, &error_abort);
> -    qemu_opt_set_number(opts, "size", size, &error_abort);
> -    qemu_opt_set_bool(opts, "share", true, &error_abort);
> -    g_free(path);
> -
> -    obj = user_creatable_add_opts(opts, &error_abort);
> -    qemu_opts_del(opts);
> -
> -    user_creatable_complete(obj, &error_abort);
> -
> -    return MEMORY_BACKEND(obj);
> -}
> -
>  static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
>  {
>      IVShmemState *s = IVSHMEM_COMMON(dev);
> @@ -914,65 +892,6 @@ static void ivshmem_common_realize(PCIDevice *dev, Error 
> **errp)
>      }
>  }
>
> -static void ivshmem_realize(PCIDevice *dev, Error **errp)
> -{
> -    IVShmemState *s = IVSHMEM_COMMON(dev);
> -
> -    if (!qtest_enabled()) {
> -        error_report("ivshmem is deprecated, please use ivshmem-plain"
> -                     " or ivshmem-doorbell instead");
> -    }
> -
> -    if (!!s->server_chr + !!s->shmobj + !!s->hostmem != 1) {
> -        error_setg(errp,
> -                   "You must specify either 'shm', 'chardev' or 'x-memdev'");
> -        return;
> -    }
> -
> -    if (s->hostmem) {
> -        if (s->sizearg) {
> -            g_warning("size argument ignored with hostmem");
> -        }
> -    } else if (s->sizearg == NULL) {
> -        s->legacy_size = 4 << 20; /* 4 MB default */
> -    } else {
> -        char *end;
> -        int64_t size = qemu_strtosz(s->sizearg, &end);
> -        if (size < 0 || (size_t)size != size || *end != '\0'
> -            || !is_power_of_2(size)) {
> -            error_setg(errp, "Invalid size %s", s->sizearg);
> -            return;
> -        }
> -        s->legacy_size = size;
> -    }
> -
> -    /* check that role is reasonable */
> -    if (s->role) {
> -        if (strncmp(s->role, "peer", 5) == 0) {
> -            s->master = ON_OFF_AUTO_OFF;
> -        } else if (strncmp(s->role, "master", 7) == 0) {
> -            s->master = ON_OFF_AUTO_ON;
> -        } else {
> -            error_setg(errp, "'role' must be 'peer' or 'master'");
> -            return;
> -        }
> -    } else {
> -        s->master = ON_OFF_AUTO_AUTO;
> -    }
> -
> -    if (s->shmobj) {
> -        s->hostmem = desugar_shm(s->shmobj, s->legacy_size);
> -    }
> -
> -    /*
> -     * Note: we don't use INTx with IVSHMEM_MSI at all, so this is a
> -     * bald-faced lie then.  But it's a backwards compatible lie.
> -     */
> -    pci_config_set_interrupt_pin(dev->config, 1);
> -
> -    ivshmem_common_realize(dev, errp);
> -}
> -
>  static void ivshmem_exit(PCIDevice *dev)
>  {
>      IVShmemState *s = IVSHMEM_COMMON(dev);
> @@ -1012,18 +931,6 @@ static void ivshmem_exit(PCIDevice *dev)
>      g_free(s->msi_vectors);
>  }
>
> -static bool test_msix(void *opaque, int version_id)
> -{
> -    IVShmemState *s = opaque;
> -
> -    return ivshmem_has_feature(s, IVSHMEM_MSI);
> -}
> -
> -static bool test_no_msix(void *opaque, int version_id)
> -{
> -    return !test_msix(opaque, version_id);
> -}
> -
>  static int ivshmem_pre_load(void *opaque)
>  {
>      IVShmemState *s = opaque;
> @@ -1042,70 +949,6 @@ static int ivshmem_post_load(void *opaque, int 
> version_id)
>      return 0;
>  }
>
> -static int ivshmem_load_old(QEMUFile *f, void *opaque, int version_id)
> -{
> -    IVShmemState *s = opaque;
> -    PCIDevice *pdev = PCI_DEVICE(s);
> -    int ret;
> -
> -    IVSHMEM_DPRINTF("ivshmem_load_old\n");
> -
> -    if (version_id != 0) {
> -        return -EINVAL;
> -    }
> -
> -    ret = ivshmem_pre_load(s);
> -    if (ret) {
> -        return ret;
> -    }
> -
> -    ret = pci_device_load(pdev, f);
> -    if (ret) {
> -        return ret;
> -    }
> -
> -    if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> -        msix_load(pdev, f);
> -    } else {
> -        s->intrstatus = qemu_get_be32(f);
> -        s->intrmask = qemu_get_be32(f);
> -    }
> -    ivshmem_vector_use(s);
> -
> -    return 0;
> -}
> -
> -static const VMStateDescription ivshmem_vmsd = {
> -    .name = "ivshmem",
> -    .version_id = 1,
> -    .minimum_version_id = 1,
> -    .pre_load = ivshmem_pre_load,
> -    .post_load = ivshmem_post_load,
> -    .fields = (VMStateField[]) {
> -        VMSTATE_PCI_DEVICE(parent_obj, IVShmemState),
> -
> -        VMSTATE_MSIX_TEST(parent_obj, IVShmemState, test_msix),
> -        VMSTATE_UINT32_TEST(intrstatus, IVShmemState, test_no_msix),
> -        VMSTATE_UINT32_TEST(intrmask, IVShmemState, test_no_msix),
> -
> -        VMSTATE_END_OF_LIST()
> -    },
> -    .load_state_old = ivshmem_load_old,
> -    .minimum_version_id_old = 0
> -};
> -
> -static Property ivshmem_properties[] = {
> -    DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
> -    DEFINE_PROP_STRING("size", IVShmemState, sizearg),
> -    DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
> -    DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, 
> false),
> -    DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
> -    DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
> -    DEFINE_PROP_STRING("role", IVShmemState, role),
> -    DEFINE_PROP_UINT32("use64", IVShmemState, not_legacy_32bit, 1),
> -    DEFINE_PROP_END_OF_LIST(),
> -};
> -
>  static void ivshmem_common_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> @@ -1123,17 +966,13 @@ static void ivshmem_common_class_init(ObjectClass 
> *klass, void *data)
>      dc->desc = "Inter-VM shared memory";
>  }
>
> -static void ivshmem_class_init(ObjectClass *klass, void *data)
> -{
> -    DeviceClass *dc = DEVICE_CLASS(klass);
> -    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> -
> -    k->realize = ivshmem_realize;
> -    k->revision = 0;
> -    dc->desc = "Inter-VM shared memory (legacy)";
> -    dc->props = ivshmem_properties;
> -    dc->vmsd = &ivshmem_vmsd;
> -}
> +static const TypeInfo ivshmem_common_info = {
> +    .name          = TYPE_IVSHMEM_COMMON,
> +    .parent        = TYPE_PCI_DEVICE,
> +    .instance_size = sizeof(IVShmemState),
> +    .abstract      = true,
> +    .class_init    = ivshmem_common_class_init,
> +};
>
>  static void ivshmem_check_memdev_is_busy(Object *obj, const char *name,
>                                           Object *val, Error **errp)
> @@ -1150,33 +989,6 @@ static void ivshmem_check_memdev_is_busy(Object *obj, 
> const char *name,
>      }
>  }
>
> -static void ivshmem_init(Object *obj)
> -{
> -    IVShmemState *s = IVSHMEM(obj);
> -
> -    object_property_add_link(obj, "x-memdev", TYPE_MEMORY_BACKEND,
> -                             (Object **)&s->hostmem,
> -                             ivshmem_check_memdev_is_busy,
> -                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
> -                             &error_abort);
> -}
> -
> -static const TypeInfo ivshmem_common_info = {
> -    .name          = TYPE_IVSHMEM_COMMON,
> -    .parent        = TYPE_PCI_DEVICE,
> -    .instance_size = sizeof(IVShmemState),
> -    .abstract      = true,
> -    .class_init    = ivshmem_common_class_init,
> -};
> -
> -static const TypeInfo ivshmem_info = {
> -    .name          = TYPE_IVSHMEM,
> -    .parent        = TYPE_IVSHMEM_COMMON,
> -    .instance_size = sizeof(IVShmemState),
> -    .instance_init = ivshmem_init,
> -    .class_init    = ivshmem_class_init,
> -};
> -
>  static const VMStateDescription ivshmem_plain_vmsd = {
>      .name = TYPE_IVSHMEM_PLAIN,
>      .version_id = 0,
> @@ -1271,6 +1083,200 @@ static const TypeInfo ivshmem_doorbell_info = {
>      .class_init    = ivshmem_doorbell_class_init,
>  };
>
> +static int ivshmem_load_old(QEMUFile *f, void *opaque, int version_id)
> +{
> +    IVShmemState *s = opaque;
> +    PCIDevice *pdev = PCI_DEVICE(s);
> +    int ret;
> +
> +    IVSHMEM_DPRINTF("ivshmem_load_old\n");
> +
> +    if (version_id != 0) {
> +        return -EINVAL;
> +    }
> +
> +    ret = ivshmem_pre_load(s);
> +    if (ret) {
> +        return ret;
> +    }
> +
> +    ret = pci_device_load(pdev, f);
> +    if (ret) {
> +        return ret;
> +    }
> +
> +    if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
> +        msix_load(pdev, f);
> +    } else {
> +        s->intrstatus = qemu_get_be32(f);
> +        s->intrmask = qemu_get_be32(f);
> +    }
> +    ivshmem_vector_use(s);
> +
> +    return 0;
> +}
> +
> +static bool test_msix(void *opaque, int version_id)
> +{
> +    IVShmemState *s = opaque;
> +
> +    return ivshmem_has_feature(s, IVSHMEM_MSI);
> +}
> +
> +static bool test_no_msix(void *opaque, int version_id)
> +{
> +    return !test_msix(opaque, version_id);
> +}
> +
> +static const VMStateDescription ivshmem_vmsd = {
> +    .name = "ivshmem",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .pre_load = ivshmem_pre_load,
> +    .post_load = ivshmem_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_PCI_DEVICE(parent_obj, IVShmemState),
> +
> +        VMSTATE_MSIX_TEST(parent_obj, IVShmemState, test_msix),
> +        VMSTATE_UINT32_TEST(intrstatus, IVShmemState, test_no_msix),
> +        VMSTATE_UINT32_TEST(intrmask, IVShmemState, test_no_msix),
> +
> +        VMSTATE_END_OF_LIST()
> +    },
> +    .load_state_old = ivshmem_load_old,
> +    .minimum_version_id_old = 0
> +};
> +
> +static Property ivshmem_properties[] = {
> +    DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
> +    DEFINE_PROP_STRING("size", IVShmemState, sizearg),
> +    DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
> +    DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD,
> +                    false),
> +    DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
> +    DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
> +    DEFINE_PROP_STRING("role", IVShmemState, role),
> +    DEFINE_PROP_UINT32("use64", IVShmemState, not_legacy_32bit, 1),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static HostMemoryBackend *desugar_shm(const char *shm, size_t size)
> +{
> +    /* TODO avoid the detour through QemuOpts */
> +    static int counter;
> +    QemuOpts *opts = qemu_opts_create(qemu_find_opts("object"),
> +                                      NULL, 0, &error_abort);
> +    char *path;
> +    Object *obj;
> +
> +    qemu_opt_set(opts, "qom-type", "memory-backend-file",
> +    &error_abort);
> +    /* FIXME need a better way to make up an ID */
> +    qemu_opts_set_id(opts, g_strdup_printf("ivshmem-backend-%d", counter++));
> +    path = g_strdup_printf("/dev/shm/%s", shm);
> +    qemu_opt_set(opts, "mem-path", path, &error_abort);
> +    qemu_opt_set_number(opts, "size", size, &error_abort);
> +    qemu_opt_set_bool(opts, "share", true, &error_abort);
> +    g_free(path);
> +
> +    obj = user_creatable_add_opts(opts, &error_abort);
> +    qemu_opts_del(opts);
> +
> +    user_creatable_complete(obj, &error_abort);
> +
> +    return MEMORY_BACKEND(obj);
> +}
> +
> +static void ivshmem_realize(PCIDevice *dev, Error **errp)
> +{
> +    IVShmemState *s = IVSHMEM_COMMON(dev);
> +
> +    if (!qtest_enabled()) {
> +        error_report("ivshmem is deprecated, please use ivshmem-plain"
> +                     " or ivshmem-doorbell instead");
> +    }
> +
> +    if (!!s->server_chr + !!s->shmobj + !!s->hostmem != 1) {
> +        error_setg(errp,
> +                   "You must specify either 'shm', 'chardev' or 'x-memdev'");
> +        return;
> +    }
> +
> +    if (s->hostmem) {
> +        if (s->sizearg) {
> +            g_warning("size argument ignored with hostmem");
> +        }
> +    } else if (s->sizearg == NULL) {
> +        s->legacy_size = 4 << 20; /* 4 MB default */
> +    } else {
> +        char *end;
> +        int64_t size = qemu_strtosz(s->sizearg, &end);
> +        if (size < 0 || (size_t)size != size || *end != '\0'
> +            || !is_power_of_2(size)) {
> +            error_setg(errp, "Invalid size %s", s->sizearg);
> +            return;
> +        }
> +        s->legacy_size = size;
> +    }
> +
> +    /* check that role is reasonable */
> +    if (s->role) {
> +        if (strncmp(s->role, "peer", 5) == 0) {
> +            s->master = ON_OFF_AUTO_OFF;
> +        } else if (strncmp(s->role, "master", 7) == 0) {
> +            s->master = ON_OFF_AUTO_ON;
> +        } else {
> +            error_setg(errp, "'role' must be 'peer' or 'master'");
> +            return;
> +        }
> +    } else {
> +        s->master = ON_OFF_AUTO_AUTO;
> +    }
> +
> +    if (s->shmobj) {
> +        s->hostmem = desugar_shm(s->shmobj, s->legacy_size);
> +    }
> +
> +    /*
> +     * Note: we don't use INTx with IVSHMEM_MSI at all, so this is a
> +     * bald-faced lie then.  But it's a backwards compatible lie.
> +     */
> +    pci_config_set_interrupt_pin(dev->config, 1);
> +
> +    ivshmem_common_realize(dev, errp);
> +}
> +
> +static void ivshmem_init(Object *obj)
> +{
> +    IVShmemState *s = IVSHMEM(obj);
> +
> +    object_property_add_link(obj, "x-memdev", TYPE_MEMORY_BACKEND,
> +                             (Object **)&s->hostmem,
> +                             ivshmem_check_memdev_is_busy,
> +                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
> +                             &error_abort);
> +}
> +
> +static void ivshmem_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> +
> +    k->realize = ivshmem_realize;
> +    k->revision = 0;
> +    dc->desc = "Inter-VM shared memory (legacy)";
> +    dc->props = ivshmem_properties;
> +    dc->vmsd = &ivshmem_vmsd;
> +}
> +
> +static const TypeInfo ivshmem_info = {
> +    .name          = TYPE_IVSHMEM,
> +    .parent        = TYPE_IVSHMEM_COMMON,
> +    .instance_size = sizeof(IVShmemState),
> +    .instance_init = ivshmem_init,
> +    .class_init    = ivshmem_class_init,
> +};
> +
>  static void ivshmem_register_types(void)
>  {
>      type_register_static(&ivshmem_common_info);
> --
> 2.4.3
>
>



-- 
Marc-André Lureau