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Old 02-22-2010, 10:13 AM   #1
pupillo
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Question syscall accessing user space

Hi, I have a simple driver.
If the calling process passes me the virtual address of an its array for example, how can I access it without using copy_from_user?

Thanks
Pupillo
 
Old 02-24-2010, 08:10 AM   #2
cladisch
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You could use get_user() which does the same for individual values.

Why don't you want to use copy_from_user()?
 
Old 02-25-2010, 01:17 AM   #3
pupillo
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Hi,
my first purpose was to understand the translation between kernel and user. As second reason there could be a performance issue.
However,I've had a look at the implementation of get_user and I saw that it just use the user virtual address...
Thanks
 
  


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