On Sun, Apr 06, 2003 at 11:35:43AM +0200, Jonathan Heusser wrote: > How do I copy best a data structure which contains two or more linked > list heads (a la linux/list.h) plus some other fields to kernelland? > Obviously a simple copy_from_user(new_struct, (struct my_struct*) data, > sizeof(struct my_struct)).. does not work. You'll need to do what is known as a "deep copy". For each struct member that is a pointer, you will need to decide if you should copy the data pointed to by the pointer, or ignore the value as being worthless on the other end of the copy, or store a placeholder value that you can use to help you figure out the correct value on the other end of the copy. Handle those elements specifically and magically. Look at kernel/fork.c do_fork(), the bits about copy_files() and so forth, for a specific example on one way to handle "deep copies". -- http://sardonix.org/
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