xref: /openbmc/qemu/hw/9pfs/9p.h (revision d25f2a72)
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 enum p9_proto_version {
98     V9FS_PROTO_2000U = 0x01,
99     V9FS_PROTO_2000L = 0x02,
100 };
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 
122 typedef struct {
123     uint32_t size_le;
124     uint8_t id;
125     uint16_t tag_le;
126 } QEMU_PACKED P9MsgHeader;
127 /* According to the specification, 9p messages start with a 7-byte header.
128  * Since most of the code uses this header size in literal form, we must be
129  * sure this is indeed the case.
130  */
131 QEMU_BUILD_BUG_ON(sizeof(P9MsgHeader) != 7);
132 
133 struct V9fsPDU
134 {
135     uint32_t size;
136     uint16_t tag;
137     uint8_t id;
138     uint8_t cancelled;
139     CoQueue complete;
140     V9fsState *s;
141     QLIST_ENTRY(V9fsPDU) next;
142     uint32_t idx;
143 };
144 
145 
146 /* FIXME
147  * 1) change user needs to set groups and stuff
148  */
149 
150 #define MAX_REQ         128
151 #define MAX_TAG_LEN     32
152 
153 #define BUG_ON(cond) assert(!(cond))
154 
155 typedef struct V9fsFidState V9fsFidState;
156 
157 enum {
158     P9_FID_NONE = 0,
159     P9_FID_FILE,
160     P9_FID_DIR,
161     P9_FID_XATTR,
162 };
163 
164 typedef struct V9fsConf
165 {
166     /* tag name for the device */
167     char *tag;
168     char *fsdev_id;
169 } V9fsConf;
170 
171 typedef struct V9fsXattr
172 {
173     uint64_t copied_len;
174     uint64_t len;
175     void *value;
176     V9fsString name;
177     int flags;
178     bool xattrwalk_fid;
179 } V9fsXattr;
180 
181 typedef struct V9fsDir {
182     DIR *stream;
183     QemuMutex readdir_mutex;
184 } V9fsDir;
185 
186 static inline void v9fs_readdir_lock(V9fsDir *dir)
187 {
188     qemu_mutex_lock(&dir->readdir_mutex);
189 }
190 
191 static inline void v9fs_readdir_unlock(V9fsDir *dir)
192 {
193     qemu_mutex_unlock(&dir->readdir_mutex);
194 }
195 
196 static inline void v9fs_readdir_init(V9fsDir *dir)
197 {
198     qemu_mutex_init(&dir->readdir_mutex);
199 }
200 
201 /*
202  * Filled by fs driver on open and other
203  * calls.
204  */
205 union V9fsFidOpenState {
206     int fd;
207     V9fsDir dir;
208     V9fsXattr xattr;
209     /*
210      * private pointer for fs drivers, that
211      * have its own internal representation of
212      * open files.
213      */
214     void *private;
215 };
216 
217 struct V9fsFidState
218 {
219     int fid_type;
220     int32_t fid;
221     V9fsPath path;
222     V9fsFidOpenState fs;
223     V9fsFidOpenState fs_reclaim;
224     int flags;
225     int open_flags;
226     uid_t uid;
227     int ref;
228     int clunked;
229     V9fsFidState *next;
230     V9fsFidState *rclm_lst;
231 };
232 
233 struct V9fsState
234 {
235     QLIST_HEAD(, V9fsPDU) free_list;
236     QLIST_HEAD(, V9fsPDU) active_list;
237     V9fsFidState *fid_list;
238     FileOperations *ops;
239     FsContext ctx;
240     char *tag;
241     enum p9_proto_version proto_version;
242     int32_t msize;
243     V9fsPDU pdus[MAX_REQ];
244     const struct V9fsTransport *transport;
245     /*
246      * lock ensuring atomic path update
247      * on rename.
248      */
249     CoRwlock rename_lock;
250     int32_t root_fid;
251     Error *migration_blocker;
252     V9fsConf fsconf;
253     V9fsQID root_qid;
254 };
255 
256 /* 9p2000.L open flags */
257 #define P9_DOTL_RDONLY        00000000
258 #define P9_DOTL_WRONLY        00000001
259 #define P9_DOTL_RDWR          00000002
260 #define P9_DOTL_NOACCESS      00000003
261 #define P9_DOTL_CREATE        00000100
262 #define P9_DOTL_EXCL          00000200
263 #define P9_DOTL_NOCTTY        00000400
264 #define P9_DOTL_TRUNC         00001000
265 #define P9_DOTL_APPEND        00002000
266 #define P9_DOTL_NONBLOCK      00004000
267 #define P9_DOTL_DSYNC         00010000
268 #define P9_DOTL_FASYNC        00020000
269 #define P9_DOTL_DIRECT        00040000
270 #define P9_DOTL_LARGEFILE     00100000
271 #define P9_DOTL_DIRECTORY     00200000
272 #define P9_DOTL_NOFOLLOW      00400000
273 #define P9_DOTL_NOATIME       01000000
274 #define P9_DOTL_CLOEXEC       02000000
275 #define P9_DOTL_SYNC          04000000
276 
277 /* 9p2000.L at flags */
278 #define P9_DOTL_AT_REMOVEDIR         0x200
279 
280 /* 9P2000.L lock type */
281 #define P9_LOCK_TYPE_RDLCK 0
282 #define P9_LOCK_TYPE_WRLCK 1
283 #define P9_LOCK_TYPE_UNLCK 2
284 
285 #define P9_LOCK_SUCCESS 0
286 #define P9_LOCK_BLOCKED 1
287 #define P9_LOCK_ERROR 2
288 #define P9_LOCK_GRACE 3
289 
290 #define P9_LOCK_FLAGS_BLOCK 1
291 #define P9_LOCK_FLAGS_RECLAIM 2
292 
293 typedef struct V9fsFlock
294 {
295     uint8_t type;
296     uint32_t flags;
297     uint64_t start; /* absolute offset */
298     uint64_t length;
299     uint32_t proc_id;
300     V9fsString client_id;
301 } V9fsFlock;
302 
303 typedef struct V9fsGetlock
304 {
305     uint8_t type;
306     uint64_t start; /* absolute offset */
307     uint64_t length;
308     uint32_t proc_id;
309     V9fsString client_id;
310 } V9fsGetlock;
311 
312 extern int open_fd_hw;
313 extern int total_open_fd;
314 
315 static inline void v9fs_path_write_lock(V9fsState *s)
316 {
317     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
318         qemu_co_rwlock_wrlock(&s->rename_lock);
319     }
320 }
321 
322 static inline void v9fs_path_read_lock(V9fsState *s)
323 {
324     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
325         qemu_co_rwlock_rdlock(&s->rename_lock);
326     }
327 }
328 
329 static inline void v9fs_path_unlock(V9fsState *s)
330 {
331     if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
332         qemu_co_rwlock_unlock(&s->rename_lock);
333     }
334 }
335 
336 static inline uint8_t v9fs_request_cancelled(V9fsPDU *pdu)
337 {
338     return pdu->cancelled;
339 }
340 
341 void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu);
342 void v9fs_path_init(V9fsPath *path);
343 void v9fs_path_free(V9fsPath *path);
344 void v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...);
345 void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs);
346 int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
347                       const char *name, V9fsPath *path);
348 int v9fs_device_realize_common(V9fsState *s, Error **errp);
349 void v9fs_device_unrealize_common(V9fsState *s, Error **errp);
350 
351 ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...);
352 ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...);
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 static inline int v9fs_register_transport(V9fsState *s,
371         const struct V9fsTransport *t)
372 {
373     assert(!s->transport);
374     s->transport = t;
375     return 0;
376 }
377 
378 #endif
379