1 /* 2 * BSD syscalls 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * Copyright (c) 2013-2014 Stacey D. Son 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, see <http://www.gnu.org/licenses/>. 19 */ 20 21 /* 22 * We need the FreeBSD "legacy" definitions. Rust needs the FreeBSD 11 system 23 * calls since it doesn't use libc at all, so we have to emulate that despite 24 * FreeBSD 11 being EOL'd. 25 */ 26 #define _WANT_FREEBSD11_STAT 27 #define _WANT_FREEBSD11_STATFS 28 #define _WANT_FREEBSD11_DIRENT 29 #define _WANT_KERNEL_ERRNO 30 #define _WANT_SEMUN 31 #include "qemu/osdep.h" 32 #include "qemu/cutils.h" 33 #include "qemu/path.h" 34 #include <sys/syscall.h> 35 #include <sys/param.h> 36 #include <sys/sysctl.h> 37 #include <utime.h> 38 39 #include "qemu.h" 40 #include "signal-common.h" 41 #include "user/syscall-trace.h" 42 43 #include "bsd-file.h" 44 45 void target_set_brk(abi_ulong new_brk) 46 { 47 } 48 49 /* 50 * errno conversion. 51 */ 52 abi_long get_errno(abi_long ret) 53 { 54 if (ret == -1) { 55 return -host_to_target_errno(errno); 56 } else { 57 return ret; 58 } 59 } 60 61 int host_to_target_errno(int err) 62 { 63 /* 64 * All the BSDs have the property that the error numbers are uniform across 65 * all architectures for a given BSD, though they may vary between different 66 * BSDs. 67 */ 68 return err; 69 } 70 71 bool is_error(abi_long ret) 72 { 73 return (abi_ulong)ret >= (abi_ulong)(-4096); 74 } 75 76 /* 77 * Unlocks a iovec. Unlike unlock_iovec, it assumes the tvec array itself is 78 * already locked from target_addr. It will be unlocked as well as all the iovec 79 * elements. 80 */ 81 static void helper_unlock_iovec(struct target_iovec *target_vec, 82 abi_ulong target_addr, struct iovec *vec, 83 int count, int copy) 84 { 85 for (int i = 0; i < count; i++) { 86 abi_ulong base = tswapal(target_vec[i].iov_base); 87 88 if (vec[i].iov_base) { 89 unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0); 90 } 91 } 92 unlock_user(target_vec, target_addr, 0); 93 } 94 95 struct iovec *lock_iovec(int type, abi_ulong target_addr, 96 int count, int copy) 97 { 98 struct target_iovec *target_vec; 99 struct iovec *vec; 100 abi_ulong total_len, max_len; 101 int i; 102 int err = 0; 103 104 if (count == 0) { 105 errno = 0; 106 return NULL; 107 } 108 if (count < 0 || count > IOV_MAX) { 109 errno = EINVAL; 110 return NULL; 111 } 112 113 vec = g_try_new0(struct iovec, count); 114 if (vec == NULL) { 115 errno = ENOMEM; 116 return NULL; 117 } 118 119 target_vec = lock_user(VERIFY_READ, target_addr, 120 count * sizeof(struct target_iovec), 1); 121 if (target_vec == NULL) { 122 err = EFAULT; 123 goto fail2; 124 } 125 126 max_len = 0x7fffffff & MIN(TARGET_PAGE_MASK, PAGE_MASK); 127 total_len = 0; 128 129 for (i = 0; i < count; i++) { 130 abi_ulong base = tswapal(target_vec[i].iov_base); 131 abi_long len = tswapal(target_vec[i].iov_len); 132 133 if (len < 0) { 134 err = EINVAL; 135 goto fail; 136 } else if (len == 0) { 137 /* Zero length pointer is ignored. */ 138 vec[i].iov_base = 0; 139 } else { 140 vec[i].iov_base = lock_user(type, base, len, copy); 141 /* 142 * If the first buffer pointer is bad, this is a fault. But 143 * subsequent bad buffers will result in a partial write; this is 144 * realized by filling the vector with null pointers and zero 145 * lengths. 146 */ 147 if (!vec[i].iov_base) { 148 if (i == 0) { 149 err = EFAULT; 150 goto fail; 151 } else { 152 /* 153 * Fail all the subsequent addresses, they are already 154 * zero'd. 155 */ 156 goto out; 157 } 158 } 159 if (len > max_len - total_len) { 160 len = max_len - total_len; 161 } 162 } 163 vec[i].iov_len = len; 164 total_len += len; 165 } 166 out: 167 unlock_user(target_vec, target_addr, 0); 168 return vec; 169 170 fail: 171 helper_unlock_iovec(target_vec, target_addr, vec, i, copy); 172 fail2: 173 g_free(vec); 174 errno = err; 175 return NULL; 176 } 177 178 void unlock_iovec(struct iovec *vec, abi_ulong target_addr, 179 int count, int copy) 180 { 181 struct target_iovec *target_vec; 182 183 target_vec = lock_user(VERIFY_READ, target_addr, 184 count * sizeof(struct target_iovec), 1); 185 if (target_vec) { 186 helper_unlock_iovec(target_vec, target_addr, vec, count, copy); 187 } 188 189 g_free(vec); 190 } 191 192 /* 193 * do_syscall() should always have a single exit point at the end so that 194 * actions, such as logging of syscall results, can be performed. All errnos 195 * that do_syscall() returns must be -TARGET_<errcode>. 196 */ 197 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1, 198 abi_long arg2, abi_long arg3, abi_long arg4, 199 abi_long arg5, abi_long arg6, abi_long arg7, 200 abi_long arg8) 201 { 202 return 0; 203 } 204 205 void syscall_init(void) 206 { 207 } 208