1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * Basic file system reading code for standalone I/O system.
31 * Simulates a primitive UNIX I/O system (read(), write(), open(), etc).
32 * Does not support writes.
33 */
34
35 /*
36 * WARNING:
37 * This is currently used by installgrub for creating bootable floppy.
38 * The special part is diskread_callback/fileread_callback for gathering
39 * fileblock list.
40 */
41
42 #include <sys/param.h>
43 #include <sys/sysmacros.h>
44 #include <sys/vnode.h>
45 #include <sys/fs/pc_label.h>
46 #include <sys/bootvfs.h>
47 #include <sys/filep.h>
48 #include "pcfilep.h"
49
50 #if defined(_BOOT)
51 #include "../common/util.h"
52 #elif defined(_KERNEL)
53 #include <sys/sunddi.h>
54 #else
55 #include <stdio.h>
56 #include <strings.h>
57 #include <ctype.h>
58 #endif
59
60 #if defined(_BOOT)
61 #define dprintf if (bootrd_debug) printf
62 #elif defined(_KERNEL)
63 #define printf kobj_printf
64 #define dprintf if (bootrd_debug) kobj_printf
65
66 /* PRINTLIKE */
67 extern void kobj_printf(char *, ...);
68 #else
69 #define dprintf if (bootrd_debug) printf
70 #endif
71
72 #define FI_STARTCLUST(fp) (*(ushort_t *)(fp)->fi_buf)
73 #define FI_LENGTH(fp) (*(long *)((fp)->fi_buf + 4))
74
75 extern int bootrd_debug;
76 extern void *bkmem_alloc(size_t);
77 extern void bkmem_free(void *, size_t);
78
79 /*
80 * NOTE: The fileread_callback is set by the calling program
81 * during a file read. diskread_callback is set to fileread_callback
82 * only if reading a file block. It needs to be NULL while reading
83 * cluster blocks.
84 */
85 extern int (*diskread_callback)(int, int);
86 extern int (*fileread_callback)(int, int);
87
88 /*
89 * Local prototypes
90 */
91 static int lookuppn(char *, _dir_entry_p);
92 static fileid_t *find_fp(int);
93 static void *readblock(int, int);
94 static int fat_map(int, int);
95 static int cluster_valid(long, int);
96 static int fat_ctodb(int, int);
97
98 static int bpcfs_mountroot(char *str);
99 static int bpcfs_unmountroot(void);
100 static int bpcfs_open(char *str, int flags);
101 static int bpcfs_close(int fd);
102 static void bpcfs_closeall(void);
103 static ssize_t bpcfs_read(int fdesc, char *buf, size_t count);
104 static off_t bpcfs_lseek(int fdesc, off_t addr, int whence);
105
106 static fileid_t *head;
107 static _fat_controller_p pcfsp;
108
109 /* cache the cluster */
110 static int nsec_cache;
111 static int nsec_start;
112 static char *cluster_cache;
113
114 /*ARGSUSED*/
115 static int
bpcfs_mountroot(char * str)116 bpcfs_mountroot(char *str)
117 {
118 int ncluster;
119 if (pcfsp != NULL)
120 return (0); /* already mounted */
121
122 pcfsp = bkmem_alloc(sizeof (_fat_controller_t));
123 head = (fileid_t *)bkmem_alloc(sizeof (fileid_t));
124 head->fi_back = head->fi_forw = head;
125 head->fi_filedes = 0;
126 head->fi_taken = 0;
127
128 /* read of first floppy sector */
129 head->fi_blocknum = 0;
130 head->fi_count = SECSIZ;
131 head->fi_memp = (caddr_t)pcfsp->f_sector;
132 if (diskread(head)) {
133 printf("failed to read first sector\n");
134 bkmem_free(pcfsp, sizeof (*pcfsp));
135 pcfsp = NULL;
136 return (-1);
137 }
138
139 if (pcfsp->f_bpb.bs_spc == 0) {
140 printf("invalid bios paramet block\n");
141 return (-1);
142 }
143
144 pcfsp->f_rootsec =
145 (pcfsp->f_bpb.bs_num_fats * ltohs(pcfsp->f_bpb.bs_spf)) +
146 ltohs(pcfsp->f_bpb.bs_resv_sectors);
147 pcfsp->f_rootlen =
148 ltohs(pcfsp->f_bpb.bs_num_root_entries) *
149 sizeof (_dir_entry_t) / SECSIZ;
150 pcfsp->f_adjust = 0;
151 pcfsp->f_dclust = CLUSTER_ROOTDIR;
152 pcfsp->f_filesec = pcfsp->f_rootsec + pcfsp->f_rootlen;
153 pcfsp->f_nxtfree = CLUSTER_FIRST;
154
155 /* figure out the number of clusters in this partition */
156 ncluster = (((ulong_t)ltohs(pcfsp->f_bpb.bs_siv) ?
157 (ulong_t)ltohs(pcfsp->f_bpb.bs_siv) :
158 (ulong_t)ltohi(pcfsp->f_bpb.bs_siv)) -
159 pcfsp->f_filesec) / (ulong_t)pcfsp->f_bpb.bs_spc;
160 pcfsp->f_16bit = ncluster >= CLUSTER_MAX_12;
161 pcfsp->f_ncluster = ncluster;
162
163 /* cache the cluster */
164 if (pcfsp->f_16bit)
165 nsec_cache = (((ncluster << 1) + 511) >> 9);
166 else
167 nsec_cache = (ncluster + ((ncluster + 1) >> 1) + 511) >> 9;
168 cluster_cache = bkmem_alloc(nsec_cache * SECSIZ);
169 if (cluster_cache == NULL) {
170 printf("bpcfs_mountroot: out of memory\n");
171 bkmem_free(pcfsp, sizeof (*pcfsp));
172 pcfsp = NULL;
173 return (-1);
174 }
175
176 head->fi_blocknum = nsec_start =
177 ltohs(pcfsp->f_bpb.bs_resv_sectors) + pcfsp->f_adjust;
178 head->fi_count = nsec_cache * SECSIZ;
179 head->fi_memp = cluster_cache;
180 if (diskread(head)) {
181 printf("bpcfs_mountroot: failed to read cluster\n");
182 bkmem_free(pcfsp, sizeof (*pcfsp));
183 pcfsp = NULL;
184 return (-1);
185 }
186 dprintf("read cluster sectors %d starting at %d\n",
187 nsec_cache, nsec_start);
188 return (0);
189 }
190
191 static int
bpcfs_unmountroot(void)192 bpcfs_unmountroot(void)
193 {
194 if (pcfsp == NULL)
195 return (-1);
196
197 (void) bpcfs_closeall();
198
199 return (0);
200 }
201
202 /*
203 * Open a file.
204 */
205 /*ARGSUSED*/
206 int
bpcfs_open(char * str,int flags)207 bpcfs_open(char *str, int flags)
208 {
209 static int filedes = 1;
210
211 fileid_t *filep;
212 _dir_entry_t d;
213
214 dprintf("open %s\n", str);
215 filep = (fileid_t *)bkmem_alloc(sizeof (fileid_t));
216 filep->fi_back = head->fi_back;
217 filep->fi_forw = head;
218 head->fi_back->fi_forw = filep;
219 head->fi_back = filep;
220 filep->fi_filedes = filedes++;
221 filep->fi_taken = 1;
222 filep->fi_path = (char *)bkmem_alloc(strlen(str) + 1);
223 (void) strcpy(filep->fi_path, str);
224
225 if (lookuppn(str, &d)) {
226 (void) bpcfs_close(filep->fi_filedes);
227 return (-1);
228 }
229
230 filep->fi_offset = 0;
231 FI_STARTCLUST(filep) = d.d_cluster;
232 FI_LENGTH(filep) = d.d_size;
233 dprintf("file %s size = %ld\n", str, d.d_size);
234 return (filep->fi_filedes);
235 }
236
237 int
bpcfs_close(int fd)238 bpcfs_close(int fd)
239 {
240 fileid_t *filep;
241
242 dprintf("close %d\n", fd);
243 if (!(filep = find_fp(fd)))
244 return (-1);
245
246 if (filep->fi_taken == 0 || filep == head) {
247 printf("File descripter %d no allocated!\n", fd);
248 return (-1);
249 }
250
251 /* unlink and deallocate node */
252 filep->fi_forw->fi_back = filep->fi_back;
253 filep->fi_back->fi_forw = filep->fi_forw;
254 bkmem_free(filep->fi_path, strlen(filep->fi_path) + 1);
255 bkmem_free((char *)filep, sizeof (fileid_t));
256 dprintf("close done\n");
257 return (0);
258 }
259
260 static void
bpcfs_closeall(void)261 bpcfs_closeall(void)
262 {
263 fileid_t *filep;
264
265 while ((filep = head->fi_forw) != head)
266 if (filep->fi_taken && bpcfs_close(filep->fi_filedes))
267 printf("Filesystem may be inconsistent.\n");
268
269 bkmem_free(pcfsp, sizeof (*pcfsp));
270 bkmem_free(head, sizeof (fileid_t));
271 pcfsp = NULL;
272 head = NULL;
273 }
274
275 static ssize_t
bpcfs_read(int fd,caddr_t b,size_t c)276 bpcfs_read(int fd, caddr_t b, size_t c)
277 {
278 ulong_t sector;
279 uint_t count = 0, xfer, i;
280 char *block;
281 ulong_t off, blk;
282 int rd, spc;
283 fileid_t *fp;
284
285 dprintf("bpcfs_read: fd = %d, buf = %p, size = %d\n",
286 fd, (void *)b, c);
287 fp = find_fp(fd);
288 if (fp == NULL) {
289 printf("invalid file descriptor %d\n", fd);
290 return (-1);
291 }
292
293 spc = pcfsp->f_bpb.bs_spc;
294 off = fp->fi_offset;
295 blk = FI_STARTCLUST(fp);
296 rd = blk == CLUSTER_ROOTDIR ? 1 : 0;
297
298 spc = pcfsp->f_bpb.bs_spc;
299 off = fp->fi_offset;
300 blk = FI_STARTCLUST(fp);
301 rd = (blk == CLUSTER_ROOTDIR) ? 1 : 0;
302
303 if ((c = MIN(FI_LENGTH(fp) - off, c)) == 0)
304 return (0);
305
306 while (off >= pcfsp->f_bpb.bs_spc * SECSIZ) {
307 blk = fat_map(blk, rd);
308 off -= pcfsp->f_bpb.bs_spc * SECSIZ;
309
310 if (!cluster_valid(blk, rd)) {
311 printf("bpcfs_read: invalid cluster: %ld, %d\n",
312 blk, rd);
313 return (-1);
314 }
315 }
316
317 while (count < c) {
318 sector = fat_ctodb(blk, rd);
319 diskread_callback = fileread_callback;
320 for (i = ((off / SECSIZ) % pcfsp->f_bpb.bs_spc); i < spc; i++) {
321 xfer = MIN(SECSIZ - (off % SECSIZ), c - count);
322 if (xfer == 0)
323 break; /* last sector done */
324
325 block = (char *)readblock(sector + i, 1);
326 if (block == NULL) {
327 return (-1);
328 }
329 dprintf("bpcfs_read: read %d bytes\n", xfer);
330 if (diskread_callback == NULL)
331 (void) bcopy(&block[off % SECSIZ], b, xfer);
332 count += xfer;
333 off += xfer;
334 b += xfer;
335 }
336
337 diskread_callback = NULL;
338 if (count < c) {
339 blk = fat_map(blk, rd);
340 if (!cluster_valid(blk, rd)) {
341 printf("bpcfs_read: invalid cluster: %ld, %d\n",
342 blk, rd);
343 break;
344 }
345 }
346 }
347
348 fp->fi_offset += count;
349 return (count);
350 }
351
352 /*
353 * This version of seek() only performs absolute seeks (whence == 0).
354 */
355 static off_t
bpcfs_lseek(int fd,off_t addr,int whence)356 bpcfs_lseek(int fd, off_t addr, int whence)
357 {
358 fileid_t *filep;
359
360 dprintf("lseek %d, off = %lx\n", fd, addr);
361 if (!(filep = find_fp(fd)))
362 return (-1);
363
364 switch (whence) {
365 case SEEK_CUR:
366 filep->fi_offset += addr;
367 break;
368 case SEEK_SET:
369 filep->fi_offset = addr;
370 break;
371 default:
372 case SEEK_END:
373 printf("lseek(): invalid whence value %d\n", whence);
374 break;
375 }
376
377 filep->fi_blocknum = addr / DEV_BSIZE;
378 filep->fi_count = 0;
379 return (0);
380 }
381
382 static fileid_t *
find_fp(int fd)383 find_fp(int fd)
384 {
385 fileid_t *filep = head;
386
387 if (fd >= 0) {
388 while ((filep = filep->fi_forw) != head)
389 if (fd == filep->fi_filedes)
390 return (filep->fi_taken ? filep : 0);
391 }
392
393 return (0);
394 }
395
396 static int
cluster_valid(long c,int rd)397 cluster_valid(long c, int rd)
398 {
399 return ((rd && (c == 0)) ? 1 : (c >= CLUSTER_RES_16_0 ? 0 : c));
400 }
401
402 static int
fat_ctodb(int blk,int r)403 fat_ctodb(int blk, int r)
404 {
405 uint_t s;
406
407 s = r ? blk + pcfsp->f_rootsec + pcfsp->f_adjust :
408 ((blk - 2) * pcfsp->f_bpb.bs_spc) +
409 pcfsp->f_filesec + pcfsp->f_adjust;
410
411 return (s);
412 }
413
414 static int
fat_map(int blk,int rootdir)415 fat_map(int blk, int rootdir)
416 {
417 ulong_t sectn, fat_index;
418 uchar_t *fp;
419
420 if (rootdir) {
421 return (blk > pcfsp->f_rootlen ? CLUSTER_EOF : blk + 1);
422 }
423
424 /* ---- Find out what sector this cluster is in ---- */
425 fat_index = (pcfsp->f_16bit) ? ((ulong_t)blk << 1) :
426 ((ulong_t)blk + ((uint_t)blk >> 1));
427
428 sectn = (fat_index / SECSIZ) + ltohs(pcfsp->f_bpb.bs_resv_sectors)
429 + pcfsp->f_adjust;
430
431 /*
432 * Read two sectors so that if our fat_index points at the last byte
433 * byte we'll have the data needed. This is only a problem for fat12
434 * entries.
435 */
436 if (!(fp = (uchar_t *)readblock(sectn, 2))) {
437 printf("fat_map: bad cluster\n");
438 return (CLUSTER_BAD_16);
439 }
440
441 fp += (fat_index % SECSIZ);
442
443 if (pcfsp->f_16bit)
444 blk = fp[0] | (fp[1] << 8);
445 else {
446 if (blk & 1)
447 blk = ((fp[0] >> 4) & 0xf) | (fp[1] << 4);
448 else
449 blk = ((fp[1] & 0xf) << 8) | fp[0];
450
451 /*
452 * This makes compares easier because we can just compare
453 * against one value instead of two.
454 */
455 if (blk >= CLUSTER_RES_12_0)
456 blk |= CLUSTER_RES_16_0;
457 }
458 return (blk);
459 }
460
461 static int
namecmp(char * pn,char * dn,int cs)462 namecmp(char *pn, char *dn, int cs)
463 {
464 dprintf("namecmp %s, %s, len = %d\n", pn, dn, cs);
465
466 /* starting char must match */
467 while (*pn && *dn) {
468 --cs;
469 if (toupper(*pn++) != toupper(*dn++))
470 return (1);
471 }
472
473 dprintf("namecmp: cs = %d\n", cs);
474 /* remainder should be either ~# or all spaces */
475 if (cs > 0 && *dn == '~')
476 return (0);
477 while (cs > 0) {
478 if (*dn++ != ' ')
479 return (1);
480 --cs;
481 }
482 return (0);
483 }
484
485 static int
dircmp(char * name,char * d_name,char * d_ext)486 dircmp(char *name, char *d_name, char *d_ext)
487 {
488 int ret;
489 char *sep, *ext;
490
491 sep = (char *)strchr(name, '.');
492
493 if (sep) {
494 *sep = '\0';
495 ext = sep + 1;
496 } else
497 ext = " ";
498
499 if (namecmp(name, d_name, NAMESIZ) || namecmp(ext, d_ext, EXTSIZ))
500 ret = 1;
501 else
502 ret = 0;
503 if (sep)
504 *sep = '.';
505 return (ret);
506 }
507
508 static int
lookup(char * n,_dir_entry_p dp,ulong_t dir_blk)509 lookup(char *n, _dir_entry_p dp, ulong_t dir_blk)
510 {
511 int spc = pcfsp->f_bpb.bs_spc;
512 int rd = (dir_blk == CLUSTER_ROOTDIR ? 1 : 0);
513 _dir_entry_p dxp;
514 int j, sector;
515
516 dprintf("lookup: name = %s\n", n);
517
518 while (cluster_valid(dir_blk, rd)) {
519 sector = fat_ctodb(dir_blk, rd);
520 dxp = readblock(sector, 1); /* read one sector */
521 if (dxp == NULL)
522 return (0);
523 for (j = 0; j < DIRENTS * spc; j++, dxp++) {
524 dprintf("lookup: dir entry %s.%s;\n",
525 dxp->d_name, dxp->d_ext);
526 if (dxp->d_name[0] == 0)
527 return (0);
528 if ((uchar_t)dxp->d_name[0] != 0xE5 &&
529 (dxp->d_attr & (DE_LABEL|DE_HIDDEN)) == 0 &&
530 dircmp(n, dxp->d_name, dxp->d_ext) == 0) {
531 dprintf("lookup: match found\n");
532 (void) bcopy(dxp, dp, sizeof (*dp));
533 return (1);
534 }
535 }
536 /* next cluster */
537 dir_blk = fat_map(dir_blk, rd);
538 }
539
540 return (0);
541 }
542
543 static int
lookuppn(char * n,_dir_entry_p dp)544 lookuppn(char *n, _dir_entry_p dp)
545 {
546 long dir_blk;
547 char name[8 + 1 + 3 + 1]; /* <8>.<3>'\0' */
548 char *p, *ep;
549 _dir_entry_t dd;
550
551 dprintf("lookuppn: path = %s\n", n);
552 dir_blk = pcfsp->f_dclust;
553 if ((*n == '\\') || (*n == '/')) {
554 dir_blk = CLUSTER_ROOTDIR;
555 while ((*n == '\\') || (*n == '/'))
556 n++;
557 if (*n == '\0') {
558 (void) bzero(dp, sizeof (*dp));
559 dp->d_cluster = CLUSTER_ROOTDIR;
560 dp->d_attr = DE_DIRECTORY;
561 return (0);
562 }
563 }
564
565 ep = &name[0] + sizeof (name);
566 while (*n) {
567 (void) bzero(name, sizeof (name));
568 p = &name[0];
569 while (*n && (*n != '\\') && (*n != '/'))
570 if (p != ep)
571 *p++ = *n++;
572 else {
573 dprintf("return, name %s is too long\n", name);
574 return (-1); /* name is too long */
575 }
576 while ((*n == '\\') || (*n == '/'))
577 n++;
578 if (lookup(name, &dd, dir_blk) == 0) {
579 dprintf("return, name %s not found\n", name);
580 return (-1);
581 }
582 dprintf("dd = %x:%x:%x attr = %x\n",
583 *(int *)&dd, *(((int *)&dd) + 1),
584 *(((int *)&dd) + 2), dd.d_attr);
585 if (*n && ((dd.d_attr & DE_DIRECTORY) == 0)) {
586 dprintf("return, not a directory\n");
587 return (-1);
588 }
589
590 dir_blk = dd.d_cluster;
591 }
592 (void) bcopy(&dd, dp, sizeof (dd));
593 return (0);
594 }
595
596 static void *
readblock(int sector,int nsec)597 readblock(int sector, int nsec)
598 {
599 if (sector >= nsec_start && sector + nsec <= nsec_start + nsec_cache)
600 return (cluster_cache + (sector - nsec_start) * SECSIZ);
601
602 /* read disk sectors */
603 head->fi_blocknum = sector;
604 head->fi_count = nsec * SECSIZ;
605 head->fi_memp = head->fi_buf;
606 if (diskread(head)) {
607 printf("failed to %d sectors at %d\n", nsec, sector);
608 return (NULL);
609 }
610
611 return (head->fi_buf);
612 }
613
614 struct boot_fs_ops bpcfs_ops = {
615 "boot_pcfs",
616 bpcfs_mountroot,
617 bpcfs_unmountroot,
618 bpcfs_open,
619 bpcfs_close,
620 bpcfs_read,
621 bpcfs_lseek,
622 NULL
623 };
624