/*
* Copy data from kernel memory into a user buffer.
* Params:
* destInUser - address of user buffer
* srcInKernel - address of kernel buffer
* bufSize - number of bytes to copy
*
* Returns:
* true if successful, false if user buffer is invalid (i.e.,
* doesn't correspond to memory the process has a right to
* access)
*/
bool Copy_To_User(ulong_t destInUser, void *srcInKernel, ulong_t bufSize) {
struct User_Context *current = g_currentThread->userContext;
if (!Validate_User_Memory(current, destInUser, bufSize))
return false;
memcpy(User_To_Kernel(current, destInUser), srcInKernel, bufSize);
return true;
}
/*
* Copy data from kernel memory into a user buffer.
* Params:
* destInUser - address of user buffer
* srcInKernel - address of kernel buffer
* bufSize - number of bytes to copy
*
* Returns:
* true if successful, false if user buffer is invalid (i.e.,
* doesn't correspond to memory the process has a right to
* access)
*/
bool Copy_To_User(ulong_t destInUser, void* srcInKernel, ulong_t bufSize)
{
if(Validate_User_Memory(g_currentThread->userContext, destInUser, bufSize)){
memcpy( (char*)(g_currentThread->userContext)->memory + destInUser, srcInKernel, bufSize );
return true;
}else{
return false;
}
}
/*
* Copy data from user memory into a kernel buffer.
* Params:
* destInKernel - address of kernel buffer
* srcInUser - address of user buffer
* bufSize - number of bytes to copy
*
* Returns:
* true if successful, false if user buffer is invalid (i.e.,
* doesn't correspond to memory the process has a right to
* access)
*/
bool Copy_From_User(void* destInKernel, ulong_t srcInUser, ulong_t bufSize)
{
/*
* Hints:
* - the User_Context of the current process can be found
* from g_currentThread->userContext
* - the user address is an index relative to the chunk
* of memory you allocated for it
* - make sure the user buffer lies entirely in memory belonging
* to the process
*/
TODO("Copy memory from user buffer to kernel buffer");
Validate_User_Memory(NULL,0,0); /* delete this; keeps gcc happy */
}
/*
* Copy data from user memory into a kernel buffer.
* Params:
* destInKernel - address of kernel buffer
* srcInUser - address of user buffer
* bufSize - number of bytes to copy
*
* Returns:
* true if successful, false if user buffer is invalid (i.e.,
* doesn't correspond to memory the process has a right to
* access)
*/
bool Copy_From_User(void* destInKernel, ulong_t srcInUser, ulong_t bufSize)
{
/*
* Hints:
* TODO
*
* - the User_Context of the current process can be found
* from g_currentThread->userContext
* - the user address is an index relative to the chunk
* of memory you allocated for it
* - make sure the user buffer lies entirely in memory belonging
* to the process
*/
if(Validate_User_Memory(g_currentThread->userContext, srcInUser, bufSize)){
memcpy(destInKernel, (char*)(g_currentThread->userContext)->memory + srcInUser, bufSize );
return true;
}else{
return false;
}
}