xref: /openbmc/qemu/hw/9pfs/9p.h (revision fe29141b)
1 #ifndef QEMU_9P_H
2 #define QEMU_9P_H
3 
4 #include <dirent.h>
5 #include <utime.h>
6 #include <sys/resource.h>
7 #include "fsdev/file-op-9p.h"
8 #include "fsdev/9p-iov-marshal.h"
9 #include "qemu/thread.h"
10 #include "qemu/coroutine.h"
11 
12 enum {
13     P9_TLERROR = 6,
14     P9_RLERROR,
15     P9_TSTATFS = 8,
16     P9_RSTATFS,
17     P9_TLOPEN = 12,
18     P9_RLOPEN,
19     P9_TLCREATE = 14,
20     P9_RLCREATE,
21     P9_TSYMLINK = 16,
22     P9_RSYMLINK,
23     P9_TMKNOD = 18,
24     P9_RMKNOD,
25     P9_TRENAME = 20,
26     P9_RRENAME,
27     P9_TREADLINK = 22,
28     P9_RREADLINK,
29     P9_TGETATTR = 24,
30     P9_RGETATTR,
31     P9_TSETATTR = 26,
32     P9_RSETATTR,
33     P9_TXATTRWALK = 30,
34     P9_RXATTRWALK,
35     P9_TXATTRCREATE = 32,
36     P9_RXATTRCREATE,
37     P9_TREADDIR = 40,
38     P9_RREADDIR,
39     P9_TFSYNC = 50,
40     P9_RFSYNC,
41     P9_TLOCK = 52,
42     P9_RLOCK,
43     P9_TGETLOCK = 54,
44     P9_RGETLOCK,
45     P9_TLINK = 70,
46     P9_RLINK,
47     P9_TMKDIR = 72,
48     P9_RMKDIR,
49     P9_TRENAMEAT = 74,
50     P9_RRENAMEAT,
51     P9_TUNLINKAT = 76,
52     P9_RUNLINKAT,
53     P9_TVERSION = 100,
54     P9_RVERSION,
55     P9_TAUTH = 102,
56     P9_RAUTH,
57     P9_TATTACH = 104,
58     P9_RATTACH,
59     P9_TERROR = 106,
60     P9_RERROR,
61     P9_TFLUSH = 108,
62     P9_RFLUSH,
63     P9_TWALK = 110,
64     P9_RWALK,
65     P9_TOPEN = 112,
66     P9_ROPEN,
67     P9_TCREATE = 114,
68     P9_RCREATE,
69     P9_TREAD = 116,
70     P9_RREAD,
71     P9_TWRITE = 118,
72     P9_RWRITE,
73     P9_TCLUNK = 120,
74     P9_RCLUNK,
75     P9_TREMOVE = 122,
76     P9_RREMOVE,
77     P9_TSTAT = 124,
78     P9_RSTAT,
79     P9_TWSTAT = 126,
80     P9_RWSTAT,
81 };
82 
83 
84 /* qid.types */
85 enum {
86     P9_QTDIR = 0x80,
87     P9_QTAPPEND = 0x40,
88     P9_QTEXCL = 0x20,
89     P9_QTMOUNT = 0x10,
90     P9_QTAUTH = 0x08,
91     P9_QTTMP = 0x04,
92     P9_QTSYMLINK = 0x02,
93     P9_QTLINK = 0x01,
94     P9_QTFILE = 0x00,
95 };
96 
97 typedef enum P9ProtoVersion {
98     V9FS_PROTO_2000U = 0x01,
99     V9FS_PROTO_2000L = 0x02,
100 } P9ProtoVersion;
101 
102 #define P9_NOTAG    UINT16_MAX
103 #define P9_NOFID    UINT32_MAX
104 #define P9_MAXWELEM 16
105 
106 #define FID_REFERENCED          0x1
107 #define FID_NON_RECLAIMABLE     0x2
108 static inline char *rpath(FsContext *ctx, const char *path)
109 {
110     return g_strdup_printf("%s/%s", ctx->fs_root, path);
111 }
112 
113 /*
114  * ample room for Twrite/Rread header
115  * size[4] Tread/Twrite tag[2] fid[4] offset[8] count[4]
116  */
117 #define P9_IOHDRSZ 24
118 
119 typedef struct V9fsPDU V9fsPDU;
120 typedef struct V9fsState V9fsState;
121 typedef struct V9fsTransport V9fsTransport;
122 
123 typedef struct {
124     uint32_t size_le;
125     uint8_t id;
126     uint16_t tag_le;
127 } QEMU_PACKED P9MsgHeader;
128 /* According to the specification, 9p messages start with a 7-byte header.
129  * Since most of the code uses this header size in literal form, we must be
130  * sure this is indeed the case.
131  */
132 QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);
133 
134 struct V9fsPDU
135 {
136     uint32_t size;
137     uint16_t tag;
138     uint8_t id;
139     uint8_t cancelled;
140     CoQueue complete;
141     V9fsState *s;
142     QLIST_ENTRY(V9fsPDU) next;
143     uint32_t idx;
144 };
145 
146 
147 /* FIXME
148  * 1) change user needs to set groups and stuff
149  */
150 
151 #define MAX_REQ         128
152 #define MAX_TAG_LEN     32
153 
154 #define BUG_ON(cond) assert(!(cond))
155 
156 typedef struct V9fsFidState V9fsFidState;
157 
158 enum {
159     P9_FID_NONE = 0,
160     P9_FID_FILE,
161     P9_FID_DIR,
162     P9_FID_XATTR,
163 };
164 
165 typedef struct V9fsConf
166 {
167     /* tag name for the device */
168     char *tag;
169     char *fsdev_id;
170 } V9fsConf;
171 
172 typedef struct V9fsXattr
173 {
174     uint64_t copied_len;
175     uint64_t len;
176     void *value;
177     V9fsString name;
178     int flags;
179     bool xattrwalk_fid;
180 } V9fsXattr;
181 
182 typedef struct V9fsDir {
183     DIR *stream;
184     QemuMutex readdir_mutex;
185 } V9fsDir;
186 
187 static inline void v9fs_readdir_lock(V9fsDir *dir)
188 {
189     qemu_mutex_lock(&dir->readdir_mutex);
190 }
191 
192 static inline void v9fs_readdir_unlock(V9fsDir *dir)
193 {
194     qemu_mutex_unlock(&dir->readdir_mutex);
195 }
196 
197 static inline void v9fs_readdir_init(V9fsDir *dir)
198 {
199     qemu_mutex_init(&dir->readdir_mutex);
200 }
201 
202 /*
203  * Filled by fs driver on open and other
204  * calls.
205  */
206 union V9fsFidOpenState {
207     int fd;
208     V9fsDir dir;
209     V9fsXattr xattr;
210     /*
211      * private pointer for fs drivers, that
212      * have its own internal representation of
213      * open files.
214      */
215     void *private;
216 };
217 
218 struct V9fsFidState
219 {
220     int fid_type;
221     int32_t fid;
222     V9fsPath path;
223     V9fsFidOpenState fs;
224     V9fsFidOpenState fs_reclaim;
225     int flags;
226     int open_flags;
227     uid_t uid;
228     int ref;
229     int clunked;
230     V9fsFidState *next;
231     V9fsFidState *rclm_lst;
232 };
233 
234 struct V9fsState
235 {
236     QLIST_HEAD(, V9fsPDU) free_list;
237     QLIST_HEAD(, V9fsPDU) active_list;
238     V9fsFidState *fid_list;
239     FileOperations *ops;
240     FsContext ctx;
241     char *tag;
242     P9ProtoVersion proto_version;
243     int32_t msize;
244     V9fsPDU pdus[MAX_REQ];
245     const V9fsTransport *transport;
246     /*
247      * lock ensuring atomic path update
248      * on rename.
249      */
250     CoRwlock rename_lock;
251     int32_t root_fid;
252     Error *migration_blocker;
253     V9fsConf fsconf;
254     V9fsQID root_qid;
255 };
256 
257 /* 9p2000.L open flags */
258 #define P9_DOTL_RDONLY        00000000
259 #define P9_DOTL_WRONLY        00000001
260 #define P9_DOTL_RDWR          00000002
261 #define P9_DOTL_NOACCESS      00000003
262 #define P9_DOTL_CREATE        00000100
263 #define P9_DOTL_EXCL          00000200
264 #define P9_DOTL_NOCTTY        00000400
265 #define P9_DOTL_TRUNC         00001000
266 #define P9_DOTL_APPEND        00002000
267 #define P9_DOTL_NONBLOCK      00004000
268 #define P9_DOTL_DSYNC         00010000
269 #define P9_DOTL_FASYNC        00020000
270 #define P9_DOTL_DIRECT        00040000
271 #define P9_DOTL_LARGEFILE     00100000
272 #define P9_DOTL_DIRECTORY     00200000
273 #define P9_DOTL_NOFOLLOW      00400000
274 #define P9_DOTL_NOATIME       01000000
275 #define P9_DOTL_CLOEXEC       02000000
276 #define P9_DOTL_SYNC          04000000
277 
278 /* 9p2000.L at flags */
279 #define P9_DOTL_AT_REMOVEDIR         0x200
280 
281 /* 9P2000.L lock type */
282 #define P9_LOCK_TYPE_RDLCK 0
283 #define P9_LOCK_TYPE_WRLCK 1
284 #define P9_LOCK_TYPE_UNLCK 2
285 
286 #define P9_LOCK_SUCCESS 0
287 #define P9_LOCK_BLOCKED 1
288 #define P9_LOCK_ERROR 2
289 #define P9_LOCK_GRACE 3
290 
291 #define P9_LOCK_FLAGS_BLOCK 1
292 #define P9_LOCK_FLAGS_RECLAIM 2
293 
294 typedef struct V9fsFlock
295 {
296     uint8_t type;
297     uint32_t flags;
298     uint64_t start; /* absolute offset */
299     uint64_t length;
300     uint32_t proc_id;
301     V9fsString client_id;
302 } V9fsFlock;
303 
304 typedef struct V9fsGetlock
305 {
306     uint8_t type;
307     uint64_t start; /* absolute offset */
308     uint64_t length;
309     uint32_t proc_id;
310     V9fsString client_id;
311 } V9fsGetlock;
312 
313 extern int open_fd_hw;
314 extern int total_open_fd;
315 
316 static inline void v9fs_path_write_lock(V9fsState *s)
317 {
318     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
319         qemu_co_rwlock_wrlock(&s->rename_lock);
320     }
321 }
322 
323 static inline void v9fs_path_read_lock(V9fsState *s)
324 {
325     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
326         qemu_co_rwlock_rdlock(&s->rename_lock);
327     }
328 }
329 
330 static inline void v9fs_path_unlock(V9fsState *s)
331 {
332     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
333         qemu_co_rwlock_unlock(&s->rename_lock);
334     }
335 }
336 
337 static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
338 {
339     return pdu->cancelled;
340 }
341 
342 void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
343 void v9fs_path_init(V9fsPath *path);
344 void v9fs_path_free(V9fsPath *path);
345 void v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...);
346 void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs);
347 int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
348                       const char *name, V9fsPath *path);
349 int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
350                                Error **errp);
351 void v9fs_device_unrealize_common(V9fsState *s, Error **errp);
352 
353 V9fsPDU *pdu_alloc(V9fsState *s);
354 void pdu_free(V9fsPDU *pdu);
355 void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr);
356 void v9fs_reset(V9fsState *s);
357 
358 struct V9fsTransport {
359     ssize_t     (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
360                                 va_list ap);
361     ssize_t     (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
362                                   va_list ap);
363     void        (*init_in_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
364                                         unsigned int *pniov, size_t size);
365     void        (*init_out_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
366                                          unsigned int *pniov, size_t size);
367     void        (*push_and_notify)(V9fsPDU *pdu);
368 };
369 
370 #endif
371