Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 23 Apr 2001 20:58:54 +0100 (BST) | From | Matt <> | Subject | Re: ioctl arg passing |
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Matt aka Doofus festures mentioned the following:
| struct instruction_t local; | __s16 *temp; | | copy_from_user( &local, ( struct instruction_t * ) arg, sizeof( struct instruction_t ) ); | temp = kmalloc( sizeof( __s16 ) * local.rxlen, GFP_KERNEL ); | copy_from_user( temp, arg, sizeof( __s16 ) * local.rxlen );
I meant that last line to be:
copy_from_user( temp, local.rxbuf, sizeof( __s16 ) * local.rxlen ); ^^^^^^^^^^^
Which'd clear up any confusion as to why I'd want two copies of the same argument.
That's the main crux of my query, can I retrieve the value of a pointer in some struct passed via ioctl? In this case, the struct/chunk of memory referenced by local.rxbuf, (which is rxlen x 2 bytes big).
Apologies, I'm a muppet.
Matt
PS. Thanks for the help so far, I'd meant to add error checking and what not, I just kept it out to keep the e-mail smaller.
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