"Michael S. Tsirkin" <mst@xxxxxxxxxx> writes:
> The spec is very clear on this:
>
> 4.1.3.1 Driver Requirements: PCI Device Layout
>
> The driver MUST access each field using the “natural” access method,
> i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit
> fields and 8-bit accesses for 8-bit fields.
>
> Add type-safe wrappers to prevent access with incorrect width.
Applied both (for *next* merge window).
Thanks,
Rusty.
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> ---
> drivers/virtio/virtio_pci_modern.c | 37 +++++++++++++++++++++++++++++++++++++
> 1 file changed, 37 insertions(+)
>
> diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
> index 2aa38e5..4e73ef7 100644
> --- a/drivers/virtio/virtio_pci_modern.c
> +++ b/drivers/virtio/virtio_pci_modern.c
> @@ -20,6 +20,43 @@
> #define VIRTIO_PCI_NO_LEGACY
> #include "virtio_pci_common.h"
>
> +/*
> + * Type-safe wrappers for io accesses.
> + * Use these to enforce at compile time the following spec requirement:
> + *
> + * The driver MUST access each field using the “natural” access
> + * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
> + * for 16-bit fields and 8-bit accesses for 8-bit fields.
> + */
> +static inline u8 vp_ioread8(u8 __iomem *addr)
> +{
> + return ioread8(addr);
> +}
> +static inline u16 vp_ioread16 (u16 __iomem *addr)
> +{
> + return ioread16(addr);
> +}
> +
> +static inline u32 vp_ioread32(u32 __iomem *addr)
> +{
> + return ioread32(addr);
> +}
> +
> +static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
> +{
> + iowrite8(value, addr);
> +}
> +
> +static inline void vp_iowrite16(u16 value, u16 __iomem *addr)
> +{
> + iowrite16(value, addr);
> +}
> +
> +static inline void vp_iowrite32(u32 value, u32 __iomem *addr)
> +{
> + iowrite16(value, addr);
> +}
> +
> static void __iomem *map_capability(struct pci_dev *dev, int off,
> size_t minlen,
> u32 align,
> --
> MST
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
