This macro copies a single simple value from kernel space to user space. It supports simple types like char and int, but not larger data types like structures or arrays.
ptr must have pointer-to-simple-variable type, and x must be assignable to the result of dereferencing ptr .
Returns zero on success, or -EFAULT on error.
This macro copies a single simple variable from user space to kernel space. It supports simple types like char and int, but not larger data types like structures or arrays.
ptr must have pointer-to-simple-variable type, and the result of dereferencing ptr must be assignable to x without a cast.
Returns zero on success, or -EFAULT on error. On error, the variable xis set to zero.
Destination address, in user space.
Source address, in kernel space.
Number of bytes to copy.
Copy data from kernel space to user space.
Returns number of bytes that could not be copied. On success, this will be zero.
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