Hi everybody,
I need to implement the SharedUserData, which is a page of memory located at (KERNEL_BASE - 0x10000) shared between user space (read-only access) and kernel space.
Some information in that page are very accurate (system time in 100ns units for instance), so I don't think that it would be possible to create a shared page at (KERNEL_BASE - 0x10000) and refresh it fast enough.
Please correct me if I'm wrong, but I think that the way to go would be to create a copy of that page in memory and initialize it when Wine starts (some information never change, like the system root or version number). When a user space program would try to access that page, the page fault exception handler would return the appropriate data.
I'm not very familiar with Wine internals, so I might be wrong, or forget some important issues. Comments are more than welcome :-)
I'd also appreciate if someone could give me some hints about the implementation (where I should look for the page fault exception handler, where I should initialize that shared data, where I can find the needed information to initialize those data, ...).
Thanks in advance.
Laurent Pinchart