xref: /openbmc/qemu/linux-user/fd-trans.h (revision 954a6c4f)
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 
34 static inline void fd_trans_init(void)
35 {
36     qemu_mutex_init(&target_fd_trans_lock);
37 }
38 
39 static inline TargetFdDataFunc fd_trans_target_to_host_data(int fd)
40 {
41     if (fd < 0) {
42         return NULL;
43     }
44 
45     QEMU_LOCK_GUARD(&target_fd_trans_lock);
46     if (fd < target_fd_max && target_fd_trans[fd]) {
47         return target_fd_trans[fd]->target_to_host_data;
48     }
49     return NULL;
50 }
51 
52 static inline TargetFdDataFunc fd_trans_host_to_target_data(int fd)
53 {
54     if (fd < 0) {
55         return NULL;
56     }
57 
58     QEMU_LOCK_GUARD(&target_fd_trans_lock);
59     if (fd < target_fd_max && target_fd_trans[fd]) {
60         return target_fd_trans[fd]->host_to_target_data;
61     }
62     return NULL;
63 }
64 
65 static inline TargetFdAddrFunc fd_trans_target_to_host_addr(int fd)
66 {
67     if (fd < 0) {
68         return NULL;
69     }
70 
71     QEMU_LOCK_GUARD(&target_fd_trans_lock);
72     if (fd < target_fd_max && target_fd_trans[fd]) {
73         return target_fd_trans[fd]->target_to_host_addr;
74     }
75     return NULL;
76 }
77 
78 static inline void internal_fd_trans_register_unsafe(int fd,
79                                                      TargetFdTrans *trans)
80 {
81     unsigned int oldmax;
82 
83     if (fd >= target_fd_max) {
84         oldmax = target_fd_max;
85         target_fd_max = ((fd >> 6) + 1) << 6; /* by slice of 64 entries */
86         target_fd_trans = g_renew(TargetFdTrans *,
87                                   target_fd_trans, target_fd_max);
88         memset((void *)(target_fd_trans + oldmax), 0,
89                (target_fd_max - oldmax) * sizeof(TargetFdTrans *));
90     }
91     target_fd_trans[fd] = trans;
92 }
93 
94 static inline void fd_trans_register(int fd, TargetFdTrans *trans)
95 {
96     QEMU_LOCK_GUARD(&target_fd_trans_lock);
97     internal_fd_trans_register_unsafe(fd, trans);
98 }
99 
100 static inline void internal_fd_trans_unregister_unsafe(int fd)
101 {
102     if (fd >= 0 && fd < target_fd_max) {
103         target_fd_trans[fd] = NULL;
104     }
105 }
106 
107 static inline void fd_trans_unregister(int fd)
108 {
109     if (fd < 0) {
110         return;
111     }
112 
113     QEMU_LOCK_GUARD(&target_fd_trans_lock);
114     internal_fd_trans_unregister_unsafe(fd);
115 }
116 
117 static inline void fd_trans_dup(int oldfd, int newfd)
118 {
119     QEMU_LOCK_GUARD(&target_fd_trans_lock);
120     internal_fd_trans_unregister_unsafe(newfd);
121     if (oldfd < target_fd_max && target_fd_trans[oldfd]) {
122         internal_fd_trans_register_unsafe(newfd, target_fd_trans[oldfd]);
123     }
124 }
125 
126 extern TargetFdTrans target_packet_trans;
127 #ifdef CONFIG_RTNETLINK
128 extern TargetFdTrans target_netlink_route_trans;
129 #endif
130 extern TargetFdTrans target_netlink_audit_trans;
131 extern TargetFdTrans target_signalfd_trans;
132 extern TargetFdTrans target_eventfd_trans;
133 #if (defined(TARGET_NR_inotify_init) && defined(__NR_inotify_init)) || \
134     (defined(CONFIG_INOTIFY1) && defined(TARGET_NR_inotify_init1) && \
135      defined(__NR_inotify_init1))
136 extern TargetFdTrans target_inotify_trans;
137 #endif
138 #endif
139