xref: /openbmc/qemu/linux-user/fd-trans.h (revision a4e31f5d8ec90a16a250fc39d807f79ce9d99760)
1 /*
2  *  This program is free software; you can redistribute it and/or modify
3  *  it under the terms of the GNU General Public License as published by
4  *  the Free Software Foundation; either version 2 of the License, or
5  *  (at your option) any later version.
6  *
7  *  This program is distributed in the hope that it will be useful,
8  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
9  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  *  GNU General Public License for more details.
11  *
12  *  You should have received a copy of the GNU General Public License
13  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
14  */
15 
16 #ifndef FD_TRANS_H
17 #define FD_TRANS_H
18 
19 #include "qemu/lockable.h"
20 
21 typedef abi_long (*TargetFdDataFunc)(void *, size_t);
22 typedef abi_long (*TargetFdAddrFunc)(void *, abi_ulong, socklen_t);
23 typedef struct TargetFdTrans {
24     TargetFdDataFunc host_to_target_data;
25     TargetFdDataFunc target_to_host_data;
26     TargetFdAddrFunc target_to_host_addr;
27 } TargetFdTrans;
28 
29 extern TargetFdTrans **target_fd_trans;
30 extern QemuMutex target_fd_trans_lock;
31 
32 extern unsigned int target_fd_max;
33 
fd_trans_init(void)34 static inline void fd_trans_init(void)
35 {
36     qemu_mutex_init(&target_fd_trans_lock);
37 }
38 
fd_trans_prefork(void)39 static inline void fd_trans_prefork(void)
40 {
41     qemu_mutex_lock(&target_fd_trans_lock);
42 }
43 
fd_trans_postfork(void)44 static inline void fd_trans_postfork(void)
45 {
46     qemu_mutex_unlock(&target_fd_trans_lock);
47 }
48 
fd_trans_target_to_host_data(int fd)49 static inline TargetFdDataFunc fd_trans_target_to_host_data(int fd)
50 {
51     if (fd < 0) {
52         return NULL;
53     }
54 
55     QEMU_LOCK_GUARD(&target_fd_trans_lock);
56     if (fd < target_fd_max && target_fd_trans[fd]) {
57         return target_fd_trans[fd]->target_to_host_data;
58     }
59     return NULL;
60 }
61 
fd_trans_host_to_target_data(int fd)62 static inline TargetFdDataFunc fd_trans_host_to_target_data(int fd)
63 {
64     if (fd < 0) {
65         return NULL;
66     }
67 
68     QEMU_LOCK_GUARD(&target_fd_trans_lock);
69     if (fd < target_fd_max && target_fd_trans[fd]) {
70         return target_fd_trans[fd]->host_to_target_data;
71     }
72     return NULL;
73 }
74 
fd_trans_target_to_host_addr(int fd)75 static inline TargetFdAddrFunc fd_trans_target_to_host_addr(int fd)
76 {
77     if (fd < 0) {
78         return NULL;
79     }
80 
81     QEMU_LOCK_GUARD(&target_fd_trans_lock);
82     if (fd < target_fd_max && target_fd_trans[fd]) {
83         return target_fd_trans[fd]->target_to_host_addr;
84     }
85     return NULL;
86 }
87 
internal_fd_trans_register_unsafe(int fd,TargetFdTrans * trans)88 static inline void internal_fd_trans_register_unsafe(int fd,
89                                                      TargetFdTrans *trans)
90 {
91     unsigned int oldmax;
92 
93     if (fd >= target_fd_max) {
94         oldmax = target_fd_max;
95         target_fd_max = ((fd >> 6) + 1) << 6; /* by slice of 64 entries */
96         target_fd_trans = g_renew(TargetFdTrans *,
97                                   target_fd_trans, target_fd_max);
98         memset((void *)(target_fd_trans + oldmax), 0,
99                (target_fd_max - oldmax) * sizeof(TargetFdTrans *));
100     }
101     target_fd_trans[fd] = trans;
102 }
103 
fd_trans_register(int fd,TargetFdTrans * trans)104 static inline void fd_trans_register(int fd, TargetFdTrans *trans)
105 {
106     QEMU_LOCK_GUARD(&target_fd_trans_lock);
107     internal_fd_trans_register_unsafe(fd, trans);
108 }
109 
internal_fd_trans_unregister_unsafe(int fd)110 static inline void internal_fd_trans_unregister_unsafe(int fd)
111 {
112     if (fd >= 0 && fd < target_fd_max) {
113         target_fd_trans[fd] = NULL;
114     }
115 }
116 
fd_trans_unregister(int fd)117 static inline void fd_trans_unregister(int fd)
118 {
119     if (fd < 0) {
120         return;
121     }
122 
123     QEMU_LOCK_GUARD(&target_fd_trans_lock);
124     internal_fd_trans_unregister_unsafe(fd);
125 }
126 
fd_trans_dup(int oldfd,int newfd)127 static inline void fd_trans_dup(int oldfd, int newfd)
128 {
129     QEMU_LOCK_GUARD(&target_fd_trans_lock);
130     internal_fd_trans_unregister_unsafe(newfd);
131     if (oldfd < target_fd_max && target_fd_trans[oldfd]) {
132         internal_fd_trans_register_unsafe(newfd, target_fd_trans[oldfd]);
133     }
134 }
135 
136 extern TargetFdTrans target_packet_trans;
137 #ifdef CONFIG_RTNETLINK
138 extern TargetFdTrans target_netlink_route_trans;
139 #endif
140 extern TargetFdTrans target_netlink_audit_trans;
141 extern TargetFdTrans target_signalfd_trans;
142 extern TargetFdTrans target_eventfd_trans;
143 extern TargetFdTrans target_timerfd_trans;
144 #if (defined(TARGET_NR_inotify_init) && defined(__NR_inotify_init)) || \
145     (defined(CONFIG_INOTIFY1) && defined(TARGET_NR_inotify_init1) && \
146      defined(__NR_inotify_init1))
147 extern TargetFdTrans target_inotify_trans;
148 #endif
149 #endif
150