2 * common interface for OS-dependent functions
6 * This software is part of the SBCL system. See the README file for
9 * This software is derived from the CMU CL system, which was
10 * written at Carnegie Mellon University and released into the
11 * public domain. The software is in the public domain and is
12 * provided with absolutely no warranty. See the COPYING and CREDITS
13 * files for more information.
16 #if !defined(_OS_H_INCLUDED_)
18 #define _OS_H_INCLUDED_
22 /* Some standard preprocessor definitions and typedefs are needed from
23 * the OS-specific #include files. This is an attempt to document
24 * them on 20000729, by WHN the impatient reverse engineer.
26 * OS_VM_PROT_READ, OS_VM_PROT_WRITE, OS_VM_PROT_EXECUTE
27 * flags for mmap, mprotect, etc. controlling memory protection
29 * type used for flags for mmap, mprotect, etc.
32 * the type used to represent addresses? (dunno why not just void*)
33 * os_vm_size_t, os_vm_off_t
34 * corresponding to standard (POSIX?) types size_t, off_t
36 * the type used to represent context in a POSIX sigaction SA_SIGACTION
37 * handler, i.e. the actual type of the thing pointed to by the
38 * void* third argument of a handler */
40 #include "target-os.h"
43 #define OS_VM_PROT_ALL \
44 (OS_VM_PROT_READ | OS_VM_PROT_WRITE | OS_VM_PROT_EXECUTE)
46 extern os_vm_size_t os_vm_page_size
;
48 /* Do anything we need to do when starting up the runtime environment
50 extern void os_init(void);
52 /* Install any OS-dependent low-level signal handlers which are needed
53 * by the runtime environment. E.g. the signals raised by a violation
54 * of the gencgc write barrier need to be caught at a low level, and
55 * they may be SIGSEGV on one OS and SIGBUS on another, so we install
56 * them in an OS-dependent way. */
57 extern void os_install_interrupt_handlers(void);
59 /* Clear a possibly-huge region of memory using any tricks available to
60 * do it efficiently, e.g. possibly unmapping it and then remapping it.
62 * FIXME: For the x86 Linux/OpenBSD/FreeBSD ports, I'd be somewhat
63 * surprised if bzero() wasn't substantially as efficient as
64 * any tricks like this. It might make sense to benchmark it
65 * and simplify if the difference isn't too large. */
66 extern void os_zero(os_vm_address_t addr
, os_vm_size_t length
);
68 /* It looks as though this function allocates 'len' bytes at 'addr',
69 * or at an OS-chosen address if 'addr' is zero.
71 * FIXME: There was some documentation for these functions in
72 * "hp-ux.c" in the old CMU CL code. Perhaps move/merge it in here. */
73 extern os_vm_address_t
os_validate(os_vm_address_t addr
, os_vm_size_t len
);
75 /* This function seems to undo the effect of os_validate(..). */
76 extern void os_invalidate(os_vm_address_t addr
, os_vm_size_t len
);
78 /* This maps a file into memory, or calls lose(..) for various
80 extern os_vm_address_t
os_map(int fd
,
85 /* This presumably flushes the instruction cache, if that can be done
86 * explicitly. (It doesn't seem to be an issue for the i386 port,
87 * which is all that exists for SBCL. It might be important for some
88 * other architecture which CMU CL has been ported to, though. */
89 extern void os_flush_icache(os_vm_address_t addr
, os_vm_size_t len
);
91 /* This sets access rights for an area of memory, e.g.
92 * write-protecting a page so that the garbage collector can find out
93 * whether it's modified by handling the signal. */
94 extern void os_protect(os_vm_address_t addr
,
96 os_vm_prot_t protection
);
98 /* This returns true for an address which makes sense at the Lisp level. */
99 extern boolean
is_valid_lisp_addr(os_vm_address_t test
);
101 /* Given a signal context, return the address for storage of the
102 * register, of the specified offset, for that context. The offset is
103 * defined in the storage class (SC) defined in the Lisp virtual
104 * machine (i.e. the file "vm.lisp" for the appropriate architecture). */
105 os_context_register_t
*
106 os_context_register_addr(os_context_t
*context
, int offset
);
108 /* FIXME: Pending investigation, this #ifdef stays as alpha. If it
109 * turns out that the alpha truly requires this, it can change to
110 * ARCH_HAS_FLOAT_REGISTERS (currently #defined in alpha-arch.h -- CSR
113 os_context_register_t
*
114 os_context_float_register_addr(os_context_t
*context
, int offset
);
117 /* Given a signal context, return the address for storage of the
118 * program counter for that context. */
119 os_context_register_t
*os_context_pc_addr(os_context_t
*context
);
120 #ifdef ARCH_HAS_NPC_REGISTER
121 os_context_register_t
*os_context_npc_addr(os_context_t
*context
);
123 #ifdef ARCH_HAS_LINK_REGISTER
124 os_context_register_t
*os_context_lr_addr(os_context_t
*context
);
127 /* Given a signal context, return the address for storage of the
128 * system stack pointer for that context. */
129 #ifdef ARCH_HAS_STACK_POINTER
130 os_context_register_t
*os_context_sp_addr(os_context_t
*context
);
132 /* Given a signal context, return the address for storage of the
133 * signal mask for that context. */
134 sigset_t
*os_context_sigmask_addr(os_context_t
*context
);
136 /* (Note that there may be other accessors for os_context_t which
137 * depend not only on the OS, but also on the architecture, e.g.
138 * getting at EFL/EFLAGS on the x86. Such things are defined in the
139 * architecture-dependence files, not the OS-dependence files.) */
141 /* These are not architecture-specific functions, but are instead
142 * general utilities defined in terms of the architecture-specific
143 * function os_validate(..) and os_invalidate(..).
145 * FIXME: os_reallocate(..) is complicated and seems no longer to be
146 * used for anything. Perhaps we could delete it? */
147 extern os_vm_address_t
os_allocate(os_vm_size_t len
);
148 extern os_vm_address_t
os_allocate_at(os_vm_address_t addr
, os_vm_size_t len
);
149 extern os_vm_address_t
os_reallocate(os_vm_address_t addr
,
150 os_vm_size_t old_len
,
152 extern void os_deallocate(os_vm_address_t addr
, os_vm_size_t len
);
155 /* FIXME: The os_trunc_foo(..) and os_round_foo(..) macros here could
158 #define os_trunc_to_page(addr) \
159 (os_vm_address_t)(((long)(addr))&~(os_vm_page_size-1))
160 #define os_round_up_to_page(addr) \
161 os_trunc_to_page((addr)+(os_vm_page_size-1))
163 #define os_trunc_size_to_page(size) \
164 (os_vm_size_t)(((long)(size))&~(os_vm_page_size-1))
165 #define os_round_up_size_to_page(size) \
166 os_trunc_size_to_page((size)+(os_vm_page_size-1))
168 /* KLUDGE: The errno error reporting system is an ugly nonreentrant
169 * botch which nonetheless wasn't too painful in the old days.
170 * However, it's obviously not good for multithreaded programs, and n
171 * order to accommodate multithreading while retaining the C-level
172 * syntax of the old UNIX interface, errno has now been changed from a
173 * true variable to a preprocessor definition which is too hairy for
174 * us to try to unscrew in Lisp code. Instead, Lisp code calls this
175 * service routine to do whatever hackery is necessary in C code, and
176 * to return the value in a way that Lisp can understand. */
177 int os_get_errno(void);