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->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++)
71 if (p->inuse && strcmp(p->name, name) == 0) {
72 werrstr("partition name already in use");
75 for (p = tab; p < tab + nelem(tab); p++)
78 if(p == tab + nelem(tab)){
79 werrstr("no free partition slots");
85 p->name = estrdup9p(name);
87 p->length = end - start;
98 for (p = tab; p < tab + nelem(tab); p++)
99 if(p->inuse && strcmp(p->name, s) == 0)
101 if(p == tab + nelem(tab)){
102 werrstr("partition not found");
113 ctlwrite0(Req *r, char *msg, Cmdbuf *cb)
118 r->ofcall.count = r->ifcall.count;
121 respond(r, "empty control message");
125 if(strcmp(cb->f[0], "part") == 0){
127 respondcmderror(r, cb, "part takes 3 args");
130 start = strtoll(cb->f[2], 0, 0);
131 end = strtoll(cb->f[3], 0, 0);
132 if(addpart(cb->f[1], start, end) < 0){
133 respondcmderror(r, cb, "%r");
137 else if(strcmp(cb->f[0], "delpart") == 0){
139 respondcmderror(r, cb, "delpart takes 1 arg");
142 if(delpart(cb->f[1]) < 0){
143 respondcmderror(r, cb, "%r");
147 else if(strcmp(cb->f[0], "inquiry") == 0){
149 respondcmderror(r, cb, "inquiry takes 1 arg");
153 inquiry = estrdup9p(cb->f[1]);
155 else if(strcmp(cb->f[0], "geometry") == 0){
157 respondcmderror(r, cb, "geometry takes 2 args");
160 nsect = strtoll(cb->f[1], 0, 0);
161 sectsize = strtoll(cb->f[2], 0, 0);
162 if(tab[0].inuse && strcmp(tab[0].name, "data") == 0 &&
165 tab[0].length = nsect;
167 for(p = tab; p < tab + nelem(tab); p++)
168 if(p->inuse && p->offset + p->length > nsect){
174 /* pass through to underlying ctl file, if any */
175 if (write(ctlfd, msg, r->ifcall.count) != r->ifcall.count) {
176 respondcmderror(r, cb, "%r");
188 r->ofcall.count = r->ifcall.count;
190 msg = emalloc9p(r->ifcall.count+1);
191 memmove(msg, r->ifcall.data, r->ifcall.count);
192 msg[r->ifcall.count] = '\0';
194 cb = parsecmd(r->ifcall.data, r->ifcall.count);
195 ctlwrite0(r, msg, cb);
202 rootgen(int off, Dir *d, void*)
204 memset(d, 0, sizeof *d);
208 d->name = estrdup9p(sdname);
209 d->mode = DMDIR|0777;
212 d->uid = estrdup9p("partfs");
213 d->gid = estrdup9p("partfs");
214 d->muid = estrdup9p("");
221 dirgen(int off, Dir *d, void*)
226 memset(d, 0, sizeof *d);
230 d->name = estrdup9p("ctl");
238 for(p = tab; p < tab + nelem(tab); p++, n++){
242 d->name = estrdup9p(p->name);
243 d->length = p->length*sectsize;
245 d->qid.path = Qpart + p - tab;
246 d->qid.vers = p->vers;
253 d->uid = estrdup9p("partfs");
254 d->gid = estrdup9p("partfs");
255 d->muid = estrdup9p("");
260 evommem(void *a, void *b, ulong n)
262 return memmove(b, a, n);
274 q = r->fid->qid.path - Qpart;
275 if(q < 0 || q > nelem(tab) || !tab[q].inuse ||
276 tab[q].vers != r->fid->qid.vers){
277 respond(r, "unknown partition");
282 offset = r->ifcall.offset;
283 count = r->ifcall.count;
285 respond(r, "negative offset");
289 respond(r, "negative count");
292 if(offset > p->length*sectsize){
293 respond(r, "offset past end of partition");
296 if(offset+count > p->length*sectsize)
297 count = p->length*sectsize - offset;
298 offset += p->offset*sectsize;
300 if(r->ifcall.type == Tread)
301 dat = (uchar*)r->ofcall.data;
303 dat = (uchar*)r->ifcall.data;
305 /* pass i/o through to underlying file */
307 if (r->ifcall.type == Twrite) {
308 tot = write(fd, dat, count);
314 tot = read(fd, dat, count);
320 r->ofcall.count = tot;
330 switch((int)r->fid->qid.path){
332 dirread9p(r, rootgen, nil);
335 dirread9p(r, dirgen, nil);
352 switch((int)r->fid->qid.path){
355 respond(r, "write to a directory?");
369 if(r->ifcall.mode&ORCLOSE)
370 respond(r, "cannot open ORCLOSE");
372 switch((int)r->fid->qid.path){
375 if(r->ifcall.mode != OREAD){
376 respond(r, "bad mode for directory open");
392 memset(d, 0, sizeof *d);
393 d->qid = r->fid->qid;
394 d->atime = d->mtime = time0;
395 q = r->fid->qid.path;
398 d->name = estrdup9p("/");
399 d->mode = DMDIR|0777;
403 d->name = estrdup9p(sdname);
404 d->mode = DMDIR|0777;
408 d->name = estrdup9p("ctl");
414 if(q < 0 || q > nelem(tab) || tab[q].inuse == 0 ||
415 r->fid->qid.vers != tab[q].vers){
416 respond(r, "partition no longer exists");
420 d->name = estrdup9p(p->name);
421 d->length = p->length * sectsize;
426 d->uid = estrdup9p("partfs");
427 d->gid = estrdup9p("partfs");
428 d->muid = estrdup9p("");
437 spec = r->ifcall.aname;
439 respond(r, "invalid attach specifier");
442 r->ofcall.qid = (Qid){Qroot, 0, QTDIR};
443 r->fid->qid = r->ofcall.qid;
448 fswalk1(Fid *fid, char *name, Qid *qid)
452 switch((int)fid->qid.path){
454 if(strcmp(name, sdname) == 0){
455 fid->qid.path = Qdir;
456 fid->qid.type = QTDIR;
462 if(strcmp(name, "ctl") == 0){
463 fid->qid.path = Qctl;
469 for(p = tab; p < tab + nelem(tab); p++)
470 if(p->inuse && strcmp(p->name, name) == 0){
471 fid->qid.path = p - tab + Qpart;
472 fid->qid.vers = p->vers;
479 return "file not found";
497 fprint(2, "usage: %s [-Dr] [-d sdname] [-m mtpt] [-s srvname] diskimage\n",
499 fprint(2, "\tdefault mtpt is /dev\n");
504 main(int argc, char **argv)
518 sdname = EARGF(usage());
521 mtpt = EARGF(usage());
527 srvname = EARGF(usage());
538 sysfatal("%s: %r", file);
539 isdir = (dir->mode & DMDIR) != 0;
543 cname = smprint("%s/ctl", file);
544 if ((ctlfd = open(cname, ORDWR)) < 0)
545 sysfatal("open %s: %r", cname);
546 file = smprint("%s/data", file);
548 if((fd = open(file, rdonly? OREAD: ORDWR)) < 0)
549 sysfatal("open %s: %r", file);
551 sectsize = 512; /* conventional */
554 nsect = dir->length / sectsize;
557 inquiry = estrdup9p(inquiry);
559 tab[0].name = estrdup9p("data");
561 tab[0].length = nsect;
563 postmountsrv(&fs, srvname, mtpt, MBEFORE);