Hello,
Aggarwal, Vikas (OFT) wrote:
Here is the context-of-use --
The driver is for Crypto-Hardware-Accelerator(CHA). The user space
creates the Descriptors(which has data to be encrypted, type of
crypto-algorithm etc) which guides the CHA.
A dummy malloc is implemented in kernel driver which uses kmalloc and
user can request that memory(to create Descriptors) via
IOCTL(CHA_MALLOC). The idea is (most likely) to avoid the "copy from
usersapce". Then the descriptor pointer is filled with the data by
user-space which passes it back to CHA via second
IOCTL(CHA_CRYPT_REQUEST).
I am sorry, I don't know how CHA works, so I may ask stupid questions.
You say that your IOCTL(CHA_MALLOC) allocates memory in kernel-space
using kmalloc() and returns that address to the user-space. Then you say
the "user can request that memory". What do you mean by "request" ? How
does the user-space accesses this kernel-allocated memory ?
Once I'll clearly understand how it works, I'll try to give an answer
about the initial problem.
Sincerly,
Thomas
--
Thomas Petazzoni
thomas.petazzoni@xxxxxxxx
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