xref: /openbmc/qemu/linux-user/user-mmap.h (revision bc3e41a0)
1 /*
2  * user-mmap.h: prototypes for linux-user guest binary loader
3  *
4  *  This program is free software; you can redistribute it and/or modify
5  *  it under the terms of the GNU General Public License as published by
6  *  the Free Software Foundation; either version 2 of the License, or
7  *  (at your option) any later version.
8  *
9  *  This program is distributed in the hope that it will be useful,
10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  *  GNU General Public License for more details.
13  *
14  *  You should have received a copy of the GNU General Public License
15  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #ifndef LINUX_USER_USER_MMAP_H
19 #define LINUX_USER_USER_MMAP_H
20 
21 /*
22  * Guest parameters for the ADDR_COMPAT_LAYOUT personality
23  * (at present this is the only layout supported by QEMU).
24  *
25  * TASK_UNMAPPED_BASE: For mmap without hint (addr != 0), the search
26  * for unused virtual memory begins at TASK_UNMAPPED_BASE.
27  *
28  * ELF_ET_DYN_BASE: When the executable is ET_DYN (i.e. PIE), and requires
29  * an interpreter (i.e. not -static-pie), use ELF_ET_DYN_BASE instead of
30  * TASK_UNMAPPED_BASE for selecting the address of the executable.
31  * This provides some distance between the executable and the interpreter,
32  * which allows the initial brk to be placed immediately after the
33  * executable and also have room to grow.
34  *
35  * task_unmapped_base, elf_et_dyn_base: When the guest address space is
36  * limited via -R, the values of TASK_UNMAPPED_BASE and ELF_ET_DYN_BASE
37  * must be adjusted to fit.
38  */
39 extern abi_ulong task_unmapped_base;
40 extern abi_ulong elf_et_dyn_base;
41 
42 /*
43  * mmap_next_start: The base address for the next mmap without hint,
44  * increased after each successful map, starting at task_unmapped_base.
45  * This is an optimization within QEMU and not part of ADDR_COMPAT_LAYOUT.
46  */
47 extern abi_ulong mmap_next_start;
48 
49 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
50 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
51                      int flags, int fd, off_t offset);
52 int target_munmap(abi_ulong start, abi_ulong len);
53 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
54                        abi_ulong new_size, unsigned long flags,
55                        abi_ulong new_addr);
56 abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice);
57 abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong);
58 void mmap_fork_start(void);
59 void mmap_fork_end(int child);
60 
61 #endif /* LINUX_USER_USER_MMAP_H */
62