minix/lib/libsys/sys_memset.c

#include "syslib.h"

int sys_memset(endpoint_t who, unsigned long pattern,
	phys_bytes base, phys_bytes bytes)
{
/* Zero a block of data.  */
  message mess;

  if (bytes == 0L) return(OK);

  mess.m_lsys_krn_sys_memset.base = base;
  mess.m_lsys_krn_sys_memset.count = bytes;
  mess.m_lsys_krn_sys_memset.pattern = pattern;
  mess.m_lsys_krn_sys_memset.process = who;

  return(_kernel_call(SYS_MEMSET, &mess));
}
Renamed various system calls. Cleaned up system call library. Added new alert() trap to replace notify() --- current notify will be removed and alert() will be called notify() later. 2005-07-14 17:13:33 +02:00			`#include "syslib.h"`

further libexec generalization . new mode for sys_memset: include process so memset can be done in physical or virtual address space. . add a mode to mmap() that lets a process allocate uninitialized memory. . this allows an exec()er (RS, VFS, etc.) to request uninitialized memory from VM and selectively clear the ranges that don't come from a file, leaving no uninitialized memory left for the process to see. . use callbacks for clearing the process, clearing memory in the process, and copying into the process; so that the libexec code can be used from rs, vfs, and in the future, kernel (to load vm) and vm (to load boot-time processes) 2012-06-06 19:05:28 +02:00			`int sys_memset(endpoint_t who, unsigned long pattern,`
			`phys_bytes base, phys_bytes bytes)`
Renamed various system calls. Cleaned up system call library. Added new alert() trap to replace notify() --- current notify will be removed and alert() will be called notify() later. 2005-07-14 17:13:33 +02:00			`{`
			`/* Zero a block of data. */`
			`message mess;`

			`if (bytes == 0L) return(OK);`

Message type for SYS_MEMSET Change-Id: Icebd04e0c53d9653301550bb598df8719aa66ada 2014-05-20 13:18:39 +02:00			`mess.m_lsys_krn_sys_memset.base = base;`
			`mess.m_lsys_krn_sys_memset.count = bytes;`
			`mess.m_lsys_krn_sys_memset.pattern = pattern;`
			`mess.m_lsys_krn_sys_memset.process = who;`
Renamed various system calls. Cleaned up system call library. Added new alert() trap to replace notify() --- current notify will be removed and alert() will be called notify() later. 2005-07-14 17:13:33 +02:00
Removal of the system task * Userspace change to use the new kernel calls - _taskcall(SYSTASK...) changed to _kernel_call(...) - int 32 reused for the kernel calls - _do_kernel_call() to make the trap to kernel - kernel_call() to make the actuall kernel call from C using _do_kernel_call() - unlike ipc call the kernel call always succeeds as kernel is always available, however, kernel may return an error * Kernel side implementation of kernel calls - the SYSTEm task does not run, only the proc table entry is preserved - every data_copy(SYSTEM is no data_copy(KERNEL - "locking" is an empty operation now as everything runs in kernel - sys_task() is replaced by kernel_call() which copies the message into kernel, dispatches the call to its handler and finishes by either copying the results back to userspace (if need be) or by suspending the process because of VM - suspended processes are later made runnable once the memory issue is resolved, picked up by the scheduler and only at this time the call is resumed (in fact restarted) which does not need to copy the message from userspace as the message is already saved in the process structure. - no ned for the vmrestart queue, the scheduler will restart the system calls - no special case in do_vmctl(), all requests remove the RTS_VMREQUEST flag 2010-02-09 16:20:09 +01:00			`return(_kernel_call(SYS_MEMSET, &mess));`
Renamed various system calls. Cleaned up system call library. Added new alert() trap to replace notify() --- current notify will be removed and alert() will be called notify() later. 2005-07-14 17:13:33 +02:00			`}`