minix/kernel/priv.h
2010-07-06 22:05:21 +00:00

163 lines
6.6 KiB
C

#ifndef PRIV_H
#define PRIV_H
/* Declaration of the system privileges structure. It defines flags, system
* call masks, an synchronous alarm timer, I/O privileges, pending hardware
* interrupts and notifications, and so on.
* System processes each get their own structure with properties, whereas all
* user processes share one structure. This setup provides a clear separation
* between common and privileged process fields and is very space efficient.
*
* Changes:
* Nov 22, 2009 rewrite of privilege management (Cristiano Giuffrida)
* Jul 01, 2005 Created. (Jorrit N. Herder)
*/
#include <minix/com.h>
#include <minix/const.h>
#include "const.h"
#include "type.h"
/* Max. number of I/O ranges that can be assigned to a process */
#define NR_IO_RANGE 64
/* Max. number of device memory ranges that can be assigned to a process */
#define NR_MEM_RANGE 20
/* Max. number of IRQs that can be assigned to a process */
#define NR_IRQ 8
struct priv {
proc_nr_t s_proc_nr; /* number of associated process */
sys_id_t s_id; /* index of this system structure */
short s_flags; /* PREEMTIBLE, BILLABLE, etc. */
/* Asynchronous sends */
vir_bytes s_asyntab; /* addr. of table in process' address space */
size_t s_asynsize; /* number of elements in table. 0 when not in
* use
*/
short s_trap_mask; /* allowed system call traps */
sys_map_t s_ipc_to; /* allowed destination processes */
/* allowed kernel calls */
bitchunk_t s_k_call_mask[SYS_CALL_MASK_SIZE];
endpoint_t s_sig_mgr; /* signal manager for system signals */
endpoint_t s_bak_sig_mgr; /* backup signal manager for system signals */
sys_map_t s_notify_pending; /* bit map with pending notifications */
irq_id_t s_int_pending; /* pending hardware interrupts */
sigset_t s_sig_pending; /* pending signals */
timer_t s_alarm_timer; /* synchronous alarm timer */
struct far_mem s_farmem[NR_REMOTE_SEGS]; /* remote memory map */
reg_t *s_stack_guard; /* stack guard word for kernel tasks */
int s_nr_io_range; /* allowed I/O ports */
struct io_range s_io_tab[NR_IO_RANGE];
int s_nr_mem_range; /* allowed memory ranges */
struct mem_range s_mem_tab[NR_MEM_RANGE];
int s_nr_irq; /* allowed IRQ lines */
int s_irq_tab[NR_IRQ];
vir_bytes s_grant_table; /* grant table address of process, or 0 */
int s_grant_entries; /* no. of entries, or 0 */
};
/* Guard word for task stacks. */
#define STACK_GUARD ((reg_t) (sizeof(reg_t) == 2 ? 0xBEEF : 0xDEADBEEF))
/* Static privilege id definitions. */
#define NR_STATIC_PRIV_IDS NR_BOOT_PROCS
#define is_static_priv_id(id) (id >= 0 && id < NR_STATIC_PRIV_IDS)
#define static_priv_id(n) (NR_TASKS + (n))
/* Magic system structure table addresses. */
#define BEG_PRIV_ADDR (&priv[0])
#define END_PRIV_ADDR (&priv[NR_SYS_PROCS])
#define BEG_STATIC_PRIV_ADDR BEG_PRIV_ADDR
#define END_STATIC_PRIV_ADDR (BEG_STATIC_PRIV_ADDR + NR_STATIC_PRIV_IDS)
#define BEG_DYN_PRIV_ADDR END_STATIC_PRIV_ADDR
#define END_DYN_PRIV_ADDR END_PRIV_ADDR
#define priv_addr(i) (ppriv_addr)[(i)]
#define priv_id(rp) ((rp)->p_priv->s_id)
#define priv(rp) ((rp)->p_priv)
#define id_to_nr(id) priv_addr(id)->s_proc_nr
#define nr_to_id(nr) priv(proc_addr(nr))->s_id
#define may_send_to(rp, nr) (get_sys_bit(priv(rp)->s_ipc_to, nr_to_id(nr)))
/* Privilege management shorthands. */
#define spi_to(n) (1 << (static_priv_id(n)))
#define unset_usr_to(m) ((m) & ~(1 << USER_PRIV_ID))
/* The system structures table and pointers to individual table slots. The
* pointers allow faster access because now a process entry can be found by
* indexing the psys_addr array, while accessing an element i requires a
* multiplication with sizeof(struct sys) to determine the address.
*/
EXTERN struct priv priv[NR_SYS_PROCS]; /* system properties table */
EXTERN struct priv *ppriv_addr[NR_SYS_PROCS]; /* direct slot pointers */
/* Unprivileged user processes all share the privilege structure of the
* root user process.
* This id must be fixed because it is used to check send mask entries.
*/
#define USER_PRIV_ID static_priv_id(ROOT_USR_PROC_NR)
/* Specifies a null privilege id.
*/
#define NULL_PRIV_ID (-1)
/* Make sure the system can boot. The following sanity check verifies that
* the system privileges table is large enough for the number of processes
* in the boot image.
*/
#if (NR_BOOT_PROCS > NR_SYS_PROCS)
#error NR_SYS_PROCS must be larger than NR_BOOT_PROCS
#endif
/*
* Privileges masks used by the kernel.
*/
#define IDL_F (SYS_PROC | BILLABLE) /* idle task is not preemptible as we
* don't want it to interfere with the
* timer tick interrupt handler code.
* Unlike other processes idle task is
* handled in a special way and is
* preempted always if timer tick occurs
* and there is another runnable process
*/
#define TSK_F (SYS_PROC) /* other kernel tasks */
#define RSYS_F (SYS_PROC | PREEMPTIBLE | ROOT_SYS_PROC) /* root sys proc */
#define DEF_SYS_F (RSYS_F | DYN_PRIV_ID) /* default sys proc */
/* allowed traps */
#define CSK_T (1 << RECEIVE) /* clock and system */
#define TSK_T 0 /* other kernel tasks */
#define RSYS_T (~0) /* root system proc */
#define DEF_SYS_T RSYS_T /* default sys proc */
/* allowed targets */
#define TSK_M 0 /* all kernel tasks */
#define RSYS_M (~0) /* root system proc */
#define DEF_SYS_M unset_usr_to(RSYS_M) /* default sys proc */
/* allowed kernel calls */
#define NO_C 0 /* no calls allowed */
#define ALL_C 1 /* all calls allowed */
#define TSK_KC NO_C /* all kernel tasks */
#define RSYS_KC ALL_C /* root system proc */
#define DEF_SYS_KC RSYS_KC /* default sys proc */
/* signal manager */
#define RSYS_SM SELF /* root system proc */
#define DEF_SYS_SM ROOT_SYS_PROC_NR /* default sys proc */
/* scheduler */
#define KERN_SCH KERNEL /* scheduled by kernel */
#define USER_SCH SCHED_PROC_NR /* scheduled in userland */
#endif /* PRIV_H */