Re: [Xen-devel] [PATCH v2 06/16] Xen: ARM: Add support for mapping platform device mmio

[Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>]

On Fri, 15 Jan 2016, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> 
> Add a bus_notifier for platform bus device in order to map the device
> mmio regions when DOM0 booting with ACPI.
> 
> Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> ---
>  drivers/xen/Makefile     |   1 +
>  drivers/xen/arm-device.c | 140 
> +++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 141 insertions(+)
>  create mode 100644 drivers/xen/arm-device.c
> 
> diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
> index aa8a7f7..0c087b1 100644
> --- a/drivers/xen/Makefile
> +++ b/drivers/xen/Makefile
> @@ -9,6 +9,7 @@ CFLAGS_features.o                     := $(nostackp)
>  
>  CFLAGS_efi.o                         += -fshort-wchar
>  
> +dom0-$(CONFIG_ARM64) += arm-device.o
>  dom0-$(CONFIG_PCI) += pci.o
>  dom0-$(CONFIG_USB_SUPPORT) += dbgp.o
>  dom0-$(CONFIG_XEN_ACPI) += acpi.o $(xen-pad-y)
> diff --git a/drivers/xen/arm-device.c b/drivers/xen/arm-device.c
> new file mode 100644
> index 0000000..7d902ea
> --- /dev/null
> +++ b/drivers/xen/arm-device.c
> @@ -0,0 +1,140 @@
> +/*
> + * Copyright (c) 2015, Linaro Limited, Shannon Zhao
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <linux/acpi.h>
> +#include <xen/xen.h>
> +#include <xen/page.h>
> +#include <xen/interface/memory.h>
> +#include <asm/xen/hypervisor.h>
> +#include <asm/xen/hypercall.h>
> +
> +static int xen_unmap_device_mmio(struct resource *resource, unsigned int 
> count)
> +{
> +     unsigned int i, j, nr;
> +     int rc = 0;
> +     struct resource *r;
> +     struct xen_remove_from_physmap xrp;
> +
> +     for (i = 0; i < count; i++) {
> +             r = &resource[i];
> +             nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE);
> +             if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0))
> +                     continue;
> +
> +             for (j = 0; j < nr; j++) {
> +                     xrp.domid = DOMID_SELF;
> +                     xrp.gpfn = XEN_PFN_DOWN(r->start) + j;
> +                     rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap,
> +                                               &xrp);
> +                     if (rc)
> +                             return rc;
> +             }
> +     }
> +
> +     return rc;
> +}
> +
> +static int xen_map_device_mmio(struct resource *resource, unsigned int count)
> +{
> +     unsigned int i, j, nr;
> +     int rc = 0;
> +     struct resource *r;
> +     xen_pfn_t *gpfns;
> +     xen_ulong_t *idxs;
> +     int *errs;
> +     struct xen_add_to_physmap_range xatp;
> +
> +     for (i = 0; i < count; i++) {
> +             r = &resource[i];
> +             nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE);
> +             if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0))
> +                     continue;
> +
> +             gpfns = kzalloc(sizeof(xen_pfn_t) * nr, GFP_KERNEL);
> +             idxs = kzalloc(sizeof(xen_ulong_t) * nr, GFP_KERNEL);
> +             errs = kzalloc(sizeof(int) * nr, GFP_KERNEL);
> +             if (!gpfns || !idxs || !errs) {
> +                     kfree(gpfns);
> +                     kfree(idxs);

kfree(errs)?

Aside from this:

Acked-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>


> +                     return -ENOMEM;
> +             }
> +
> +             for (j = 0; j < nr; j++) {
> +                     gpfns[j] = XEN_PFN_DOWN(r->start) + j;
> +                     idxs[j] = XEN_PFN_DOWN(r->start) + j;
> +             }
> +
> +             xatp.domid = DOMID_SELF;
> +             xatp.size = nr;
> +             xatp.space = XENMAPSPACE_dev_mmio;
> +
> +             set_xen_guest_handle(xatp.gpfns, gpfns);
> +             set_xen_guest_handle(xatp.idxs, idxs);
> +             set_xen_guest_handle(xatp.errs, errs);
> +
> +             rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
> +             kfree(gpfns);
> +             kfree(idxs);
> +             kfree(errs);
> +             if (rc)
> +                     return rc;
> +     }
> +
> +     return rc;
> +}
> +
> +static int xen_platform_notifier(struct notifier_block *nb,
> +                              unsigned long action, void *data)
> +{
> +     struct platform_device *pdev = to_platform_device(data);
> +     int r = 0;
> +
> +     if (pdev->num_resources == 0 || pdev->resource == NULL)
> +             return NOTIFY_OK;
> +
> +     switch (action) {
> +     case BUS_NOTIFY_ADD_DEVICE:
> +             r = xen_map_device_mmio(pdev->resource, pdev->num_resources);
> +             break;
> +     case BUS_NOTIFY_DEL_DEVICE:
> +             r = xen_unmap_device_mmio(pdev->resource, pdev->num_resources);
> +             break;
> +     default:
> +             return NOTIFY_DONE;
> +     }
> +     if (r)
> +             dev_err(&pdev->dev, "Platform: Failed to %s device %s MMIO!\n",
> +                     action == BUS_NOTIFY_ADD_DEVICE ? "map" :
> +                     (action == BUS_NOTIFY_DEL_DEVICE ? "unmap" : "?"),
> +                     pdev->name);
> +
> +     return NOTIFY_OK;
> +}
> +
> +static struct notifier_block platform_device_nb = {
> +     .notifier_call = xen_platform_notifier,
> +};
> +
> +static int __init register_xen_platform_notifier(void)
> +{
> +     if (!xen_initial_domain() || acpi_disabled)
> +             return 0;
> +
> +     return bus_register_notifier(&platform_bus_type, &platform_device_nb);
> +}
> +
> +arch_initcall(register_xen_platform_notifier);


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel