>> >>> Added support to read the vendor-specific PCI capability to identify the
>> >>> type of device being emulated.
>> >>>
>> >>> Reviewed-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>> >>> Signed-off-by: Shijith Thotton <sthotton@xxxxxxxxxxx>
>> >>> ---
>> >>> drivers/vdpa/octeon_ep/octep_vdpa.h | 20 ++++++++++++++
>> >>> drivers/vdpa/octeon_ep/octep_vdpa_hw.c | 33
>> >>+++++++++++++++++++++++-
>> >>> drivers/vdpa/octeon_ep/octep_vdpa_main.c | 4 ++-
>> >>> 3 files changed, 55 insertions(+), 2 deletions(-)
>> >>>
>> >>> diff --git a/drivers/vdpa/octeon_ep/octep_vdpa.h
>> >>b/drivers/vdpa/octeon_ep/octep_vdpa.h
>> >>> index 2cadb878e679..53b020b019f7 100644
>> >>> --- a/drivers/vdpa/octeon_ep/octep_vdpa.h
>> >>> +++ b/drivers/vdpa/octeon_ep/octep_vdpa.h
>> >>> @@ -8,6 +8,7 @@
>> >>> #include <linux/pci_regs.h>
>> >>> #include <linux/vdpa.h>
>> >>> #include <linux/virtio_pci_modern.h>
>> >>> +#include <uapi/linux/virtio_crypto.h>
>> >>> #include <uapi/linux/virtio_net.h>
>> >>> #include <uapi/linux/virtio_blk.h>
>> >>> #include <uapi/linux/virtio_config.h>
>> >>> @@ -52,6 +53,24 @@ struct octep_vring_info {
>> >>> phys_addr_t notify_pa;
>> >>> };
>> >>>
>> >>> +enum octep_pci_vndr_cfg_type {
>> >>> + OCTEP_PCI_VNDR_CFG_TYPE_VIRTIO_ID,
>> >>> + OCTEP_PCI_VNDR_CFG_TYPE_MAX,
>> >>> +};
>> >>> +
>> >>> +struct octep_pci_vndr_data {
>> >>> + struct virtio_pci_vndr_data hdr;
>> >>> + u8 id;
>> >>> + u8 bar;
>> >>> + union {
>> >>> + u64 data;
>> >>> + struct {
>> >>> + u32 offset;
>> >>> + u32 length;
>> >>> + };
>> >>> + };
>> >>> +};
>> >>
>> >>This seems not to be padded to a multiple of 4 bytes?
>> >>
>> >
>> >Looks like, the structure is naturally aligned.
>> >
>> >struct virtio_pci_vndr_data {
>> > uint8_t cap_vndr; /* 0 1 */
>> > uint8_t cap_next; /* 1 1 */
>> > uint8_t cap_len; /* 2 1 */
>> > uint8_t cfg_type; /* 3 1 */
>> > uint16_t vendor_id; /* 4 2 */
>> > /* size: 6, cachelines: 1, members: 5 */
>> > /* last cacheline: 6 bytes */
>> >};
>> >struct octep_pci_vndr_data {
>> > struct virtio_pci_vndr_data hdr; /* 0 6 */
>> > uint8_t id; /* 6 1 */
>> > uint8_t bar; /* 7 1 */
>> > union {
>> > uint64_t data; /* 8 8 */
>> > struct {
>> > uint32_t offset; /* 8 4 */
>> > uint32_t length; /* 12 4 */
>> > }; /* 8 8 */
>> > }; /* 8 8 */
>> >
>> > /* size: 16, cachelines: 1, members: 4 */
>> > /* last cacheline: 16 bytes */
>> >};
>> >
>> >I will add __attribute__((aligned(4))) to be safe.
>> >
>>
>> Small correction, I meant __attribute__((packed, aligned(4))).
>>
>> Thanks,
>> Shijith
>
>Don't add packed pls, for me it means "something is not packed naturally
>here". when in fact it is.
>
>aligned is also bad, since it can add padding which creates all
>kind of security issues.
>
>If you want to be sure, add BUILD_BUG_ON and check that it is aligned
>as expected.
Sure, I will use BUILD_BUG_ON to check the structure size.
BUILD_BUG_ON(sizeof(struct octep_pci_vndr_data) % 4 != 0);
Thanks,
Shijith
