2 * partfs - serve an underlying file, with devsd-style partitions
11 typedef struct Part Part;
18 vlong offset; /* in sectors */
19 vlong length; /* in sectors */
30 int fd = -1, ctlfd = -1;
34 vlong nsect, sectsize;
36 char *inquiry = "partfs hard drive";
37 char *sdname = "sdXX";
47 fmtprint(&fmt, "inquiry %s\n", inquiry);
48 fmtprint(&fmt, "geometry %lld %lld\n", nsect, sectsize);
49 for (p = tab; p < tab + nelem(tab); p++)
51 fmtprint(&fmt, "part %s %lld %lld\n",
52 p->name, p->offset, p->length);
53 return fmtstrflush(&fmt);
57 addpart(char *name, vlong start, vlong end)
61 if(start < 0 || start > end || end > nsect){
62 werrstr("bad partition boundaries");
66 if (strcmp(name, "ctl") == 0 || strcmp(name, "data") == 0) {
67 werrstr("partition name already in use");
70 for (p = tab; p < tab + nelem(tab) && p->inuse; p++)
71 if (strcmp(p->name, name) == 0) {
72 werrstr("partition name already in use");
75 if(p == tab + nelem(tab)){
76 werrstr("no free partition slots");
82 p->name = estrdup9p(name);
84 p->length = end - start;
95 for (p = tab; p < tab + nelem(tab); p++)
96 if(p->inuse && strcmp(p->name, s) == 0)
98 if(p == tab + nelem(tab)){
99 werrstr("partition not found");
110 ctlwrite0(Req *r, char *msg, Cmdbuf *cb)
115 r->ofcall.count = r->ifcall.count;
118 respond(r, "empty control message");
122 if(strcmp(cb->f[0], "part") == 0){
124 respondcmderror(r, cb, "part takes 3 args");
127 start = strtoll(cb->f[2], 0, 0);
128 end = strtoll(cb->f[3], 0, 0);
129 if(addpart(cb->f[1], start, end) < 0){
130 respondcmderror(r, cb, "%r");
134 else if(strcmp(cb->f[0], "delpart") == 0){
136 respondcmderror(r, cb, "delpart takes 1 arg");
139 if(delpart(cb->f[1]) < 0){
140 respondcmderror(r, cb, "%r");
144 else if(strcmp(cb->f[0], "inquiry") == 0){
146 respondcmderror(r, cb, "inquiry takes 1 arg");
150 inquiry = estrdup9p(cb->f[1]);
152 else if(strcmp(cb->f[0], "geometry") == 0){
154 respondcmderror(r, cb, "geometry takes 2 args");
157 nsect = strtoll(cb->f[1], 0, 0);
158 sectsize = strtoll(cb->f[2], 0, 0);
159 if(tab[0].inuse && strcmp(tab[0].name, "data") == 0 &&
162 tab[0].length = nsect;
164 for(p = tab; p < tab + nelem(tab); p++)
165 if(p->inuse && p->offset + p->length > nsect){
171 /* pass through to underlying ctl file, if any */
172 if (write(ctlfd, msg, r->ifcall.count) != r->ifcall.count) {
173 respondcmderror(r, cb, "%r");
185 r->ofcall.count = r->ifcall.count;
187 msg = emalloc9p(r->ifcall.count+1);
188 memmove(msg, r->ifcall.data, r->ifcall.count);
189 msg[r->ifcall.count] = '\0';
191 cb = parsecmd(r->ifcall.data, r->ifcall.count);
192 ctlwrite0(r, msg, cb);
199 rootgen(int off, Dir *d, void*)
201 memset(d, 0, sizeof *d);
205 d->name = estrdup9p(sdname);
206 d->mode = DMDIR|0777;
209 d->uid = estrdup9p("partfs");
210 d->gid = estrdup9p("partfs");
211 d->muid = estrdup9p("");
218 dirgen(int off, Dir *d, void*)
223 memset(d, 0, sizeof *d);
227 d->name = estrdup9p("ctl");
235 for(p = tab; p < tab + nelem(tab); p++, n++){
239 d->name = estrdup9p(p->name);
240 d->length = p->length*sectsize;
242 d->qid.path = Qpart + p - tab;
243 d->qid.vers = p->vers;
250 d->uid = estrdup9p("partfs");
251 d->gid = estrdup9p("partfs");
252 d->muid = estrdup9p("");
257 evommem(void *a, void *b, ulong n)
259 return memmove(b, a, n);
271 q = r->fid->qid.path - Qpart;
272 if(q < 0 || q > nelem(tab) || !tab[q].inuse ||
273 tab[q].vers != r->fid->qid.vers){
274 respond(r, "unknown partition");
279 offset = r->ifcall.offset;
280 count = r->ifcall.count;
282 respond(r, "negative offset");
286 respond(r, "negative count");
289 if(offset > p->length*sectsize){
290 respond(r, "offset past end of partition");
293 if(offset+count > p->length*sectsize)
294 count = p->length*sectsize - offset;
295 offset += p->offset*sectsize;
297 if(r->ifcall.type == Tread)
298 dat = (uchar*)r->ofcall.data;
300 dat = (uchar*)r->ifcall.data;
302 /* pass i/o through to underlying file */
304 if (r->ifcall.type == Twrite) {
305 tot = write(fd, dat, count);
311 tot = read(fd, dat, count);
317 r->ofcall.count = tot;
327 switch((int)r->fid->qid.path){
329 dirread9p(r, rootgen, nil);
332 dirread9p(r, dirgen, nil);
349 switch((int)r->fid->qid.path){
352 respond(r, "write to a directory?");
366 if(r->ifcall.mode&ORCLOSE)
367 respond(r, "cannot open ORCLOSE");
369 switch((int)r->fid->qid.path){
372 if(r->ifcall.mode != OREAD){
373 respond(r, "bad mode for directory open");
389 memset(d, 0, sizeof *d);
390 d->qid = r->fid->qid;
391 d->atime = d->mtime = time0;
392 q = r->fid->qid.path;
395 d->name = estrdup9p("/");
396 d->mode = DMDIR|0777;
400 d->name = estrdup9p(sdname);
401 d->mode = DMDIR|0777;
405 d->name = estrdup9p("ctl");
411 if(q < 0 || q > nelem(tab) || tab[q].inuse == 0 ||
412 r->fid->qid.vers != tab[q].vers){
413 respond(r, "partition no longer exists");
417 d->name = estrdup9p(p->name);
418 d->length = p->length * sectsize;
423 d->uid = estrdup9p("partfs");
424 d->gid = estrdup9p("partfs");
425 d->muid = estrdup9p("");
434 spec = r->ifcall.aname;
436 respond(r, "invalid attach specifier");
439 r->ofcall.qid = (Qid){Qroot, 0, QTDIR};
440 r->fid->qid = r->ofcall.qid;
445 fswalk1(Fid *fid, char *name, Qid *qid)
449 switch((int)fid->qid.path){
451 if(strcmp(name, sdname) == 0){
452 fid->qid.path = Qdir;
453 fid->qid.type = QTDIR;
459 if(strcmp(name, "ctl") == 0){
460 fid->qid.path = Qctl;
466 for(p = tab; p < tab + nelem(tab); p++)
467 if(p->inuse && strcmp(p->name, name) == 0){
468 fid->qid.path = p - tab + Qpart;
469 fid->qid.vers = p->vers;
476 return "file not found";
494 fprint(2, "usage: %s [-Dr] [-d sdname] [-m mtpt] [-s srvname] diskimage\n",
496 fprint(2, "\tdefault mtpt is /dev\n");
501 main(int argc, char **argv)
515 sdname = EARGF(usage());
518 mtpt = EARGF(usage());
524 srvname = EARGF(usage());
535 sysfatal("%s: %r", file);
536 isdir = (dir->mode & DMDIR) != 0;
540 cname = smprint("%s/ctl", file);
541 if ((ctlfd = open(cname, ORDWR)) < 0)
542 sysfatal("open %s: %r", cname);
543 file = smprint("%s/data", file);
545 if((fd = open(file, rdonly? OREAD: ORDWR)) < 0)
546 sysfatal("open %s: %r", file);
548 sectsize = 512; /* conventional */
551 nsect = dir->length / sectsize;
554 inquiry = estrdup9p(inquiry);
556 tab[0].name = estrdup9p("data");
558 tab[0].length = nsect;
560 postmountsrv(&fs, srvname, mtpt, MBEFORE);