This commit adds new event to notify event of phy packet with time stamp
field.
Unlike the fw_cdev_event_request3 and fw_cdev_event_response2, the size
of new structure, fw_cdev_event_phy_packet2, is multiples of 8, thus
padding is not required to keep the same size between System V ABI for
different architectures.
It is noticeable that for the case of ping request 1394 OHCI controller
does not record the isochronous cycle at which the packet was sent for
the request subaction. Instead, it records round-trip count measured by
hardware at 42.195 MHz resolution.
Cc: kunit-dev@googlegroups.com
Link: https://lore.kernel.org/r/20230529113406.986289-12-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
This commit adds new event to notify event of response subaction with
time stamp field.
Current compiler implementation of System V ABI selects one of structure
members which has the maximum alignment size in the structure to decide
the size of structure. In the case of fw_cdev_event_request3 structure,
it is closure member which has 8 byte storage. The size of alignment for
the type of 8 byte storage differs depending on architectures; 4 byte for
i386 architecture and 8 byte for the others including x32 architecture.
It is inconvenient to device driver developer to use structure layout
which varies between architectures since the developer takes care of ioctl
compat layer. This commit adds 32 bit member for padding to keep the
size of structure as multiples of 8.
Cc: kunit-dev@googlegroups.com
Link: https://lore.kernel.org/r/20230529113406.986289-9-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
This commit adds new event to notify event of request subaction with
time stamp field.
Current compiler implementation of System V ABI selects one of structure
members which has the maximum alignment size in the structure to decide
the size of structure. In the case of fw_cdev_event_request3 structure,
it is closure member which has 8 byte storage. The size of alignment for
the type of 8 byte storage differs depending on architectures; 4 byte for
i386 architecture and 8 byte for the others including x32 architecture.
It is inconvenient to device driver developer to use structure layout
which varies between architectures since the developer takes care of ioctl
compat layer. This commit adds 32 bit member for padding to keep the
size of structure as multiples of 8.
Cc: kunit-dev@googlegroups.com
Link: https://lore.kernel.org/r/20230529113406.986289-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In future commits, some new structure will be added to express new type
of event. They are exposed to user space as the part of UAPI. It is likely
to get trouble in ioctl compatibility layer for 32 bit binaries in 64 bit
host machine since the layout of structure could differ depending on
System V ABI for these architectures. Actually the subsystem already got
such trouble at v2.6.27. It is preferable to decide the layout of
structure carefully so that the layer is free from such trouble.
This commit utilizes KUnit framework to check the layout of structure for
the purpose. A test is added for the existent issue.
Cc: kunit-dev@googlegroups.com
Link: https://lore.kernel.org/r/20230529113406.986289-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
