xref: /minix/minix/kernel/priv.h (revision 9624407e)
1 #ifndef PRIV_H
2 #define PRIV_H
3 
4 /* Declaration of the system privileges structure. It defines flags, system
5  * call masks, an synchronous alarm timer, I/O privileges, pending hardware
6  * interrupts and notifications, and so on.
7  * System processes each get their own structure with properties, whereas all
8  * user processes share one structure. This setup provides a clear separation
9  * between common and privileged process fields and is very space efficient.
10  *
11  * Changes:
12  *   Nov 22, 2009  rewrite of privilege management (Cristiano Giuffrida)
13  *   Jul 01, 2005  Created.  (Jorrit N. Herder)
14  */
15 #include <minix/const.h>
16 #include <minix/priv.h>
17 #include "kernel/const.h"
18 #include "kernel/type.h"
19 #include "kernel/ipc_filter.h"
20 
21 struct priv {
22   proc_nr_t s_proc_nr;		/* number of associated process */
23   sys_id_t s_id;		/* index of this system structure */
24   short s_flags;		/* PREEMTIBLE, BILLABLE, etc. */
25   int s_init_flags;             /* initialization flags given to the process. */
26 
27   /* Asynchronous sends */
28   vir_bytes s_asyntab;		/* addr. of table in process' address space */
29   size_t s_asynsize;		/* number of elements in table. 0 when not in
30 				 * use
31 				 */
32   endpoint_t s_asynendpoint;    /* the endpoint the asyn table belongs to. */
33 
34   short s_trap_mask;		/* allowed system call traps */
35   sys_map_t s_ipc_to;		/* allowed destination processes */
36 
37   /* allowed kernel calls */
38   bitchunk_t s_k_call_mask[SYS_CALL_MASK_SIZE];
39 
40   endpoint_t s_sig_mgr;		/* signal manager for system signals */
41   endpoint_t s_bak_sig_mgr;	/* backup signal manager for system signals */
42   sys_map_t s_notify_pending;  	/* bit map with pending notifications */
43   sys_map_t s_asyn_pending;	/* bit map with pending asyn messages */
44   irq_id_t s_int_pending;	/* pending hardware interrupts */
45   sigset_t s_sig_pending;	/* pending signals */
46   ipc_filter_t *s_ipcf;         /* ipc filter (NULL when no filter is set) */
47 
48   minix_timer_t s_alarm_timer;	/* synchronous alarm timer */
49   reg_t *s_stack_guard;		/* stack guard word for kernel tasks */
50 
51   char s_diag_sig;		/* send a SIGKMESS when diagnostics arrive? */
52 
53   int s_nr_io_range;		/* allowed I/O ports */
54   struct io_range s_io_tab[NR_IO_RANGE];
55 
56   int s_nr_mem_range;		/* allowed memory ranges */
57   struct minix_mem_range s_mem_tab[NR_MEM_RANGE];
58 
59   int s_nr_irq;			/* allowed IRQ lines */
60   int s_irq_tab[NR_IRQ];
61   vir_bytes s_grant_table;	/* grant table address of process, or 0 */
62   int s_grant_entries;		/* no. of entries, or 0 */
63   endpoint_t s_grant_endpoint;  /* the endpoint the grant table belongs to */
64   vir_bytes s_state_table;	/* state table address of process, or 0 */
65   int s_state_entries;		/* no. of entries, or 0 */
66 };
67 
68 /* Guard word for task stacks. */
69 #define STACK_GUARD	((reg_t) (sizeof(reg_t) == 2 ? 0xBEEF : 0xDEADBEEF))
70 
71 /* Magic system structure table addresses. */
72 #define BEG_PRIV_ADDR              (&priv[0])
73 #define END_PRIV_ADDR              (&priv[NR_SYS_PROCS])
74 #define BEG_STATIC_PRIV_ADDR       BEG_PRIV_ADDR
75 #define END_STATIC_PRIV_ADDR       (BEG_STATIC_PRIV_ADDR + NR_STATIC_PRIV_IDS)
76 #define BEG_DYN_PRIV_ADDR          END_STATIC_PRIV_ADDR
77 #define END_DYN_PRIV_ADDR          END_PRIV_ADDR
78 
79 #define priv_addr(i)      (ppriv_addr)[(i)]
80 #define priv_id(rp)	  ((rp)->p_priv->s_id)
81 #define priv(rp)	  ((rp)->p_priv)
82 
83 #define id_to_nr(id)	priv_addr(id)->s_proc_nr
84 #define nr_to_id(nr)    priv(proc_addr(nr))->s_id
85 
86 #define may_send_to(rp, nr) (get_sys_bit(priv(rp)->s_ipc_to, nr_to_id(nr)))
87 #define may_asynsend_to(rp, nr) (may_send_to(rp, nr) || (rp)->p_nr == nr)
88 
89 /* The system structures table and pointers to individual table slots. The
90  * pointers allow faster access because now a process entry can be found by
91  * indexing the psys_addr array, while accessing an element i requires a
92  * multiplication with sizeof(struct sys) to determine the address.
93  */
94 EXTERN struct priv priv[NR_SYS_PROCS];		/* system properties table */
95 EXTERN struct priv *ppriv_addr[NR_SYS_PROCS];	/* direct slot pointers */
96 
97 /* Make sure the system can boot. The following sanity check verifies that
98  * the system privileges table is large enough for the number of processes
99  * in the boot image.
100  */
101 #if (NR_BOOT_PROCS > NR_SYS_PROCS)
102 #error NR_SYS_PROCS must be larger than NR_BOOT_PROCS
103 #endif
104 
105 #endif /* PRIV_H */
106