1 /* $NetBSD: ufs.c,v 1.20 1998/03/01 07:15:39 ross Exp $ */
4 * Copyright (c) 2002 Networks Associates Technology, Inc.
7 * This software was developed for the FreeBSD Project by Marshall
8 * Kirk McKusick and Network Associates Laboratories, the Security
9 * Research Division of Network Associates, Inc. under DARPA/SPAWAR
10 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
13 * Copyright (c) 1982, 1989, 1993
14 * The Regents of the University of California. All rights reserved.
16 * This code is derived from software contributed to Berkeley by
17 * The Mach Operating System project at Carnegie-Mellon University.
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
22 * 1. Redistributions of source code must retain the above copyright
23 * notice, this list of conditions and the following disclaimer.
24 * 2. Redistributions in binary form must reproduce the above copyright
25 * notice, this list of conditions and the following disclaimer in the
26 * documentation and/or other materials provided with the distribution.
27 * 3. Neither the name of the University nor the names of its contributors
28 * may be used to endorse or promote products derived from this software
29 * without specific prior written permission.
31 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
44 * Copyright (c) 1990, 1991 Carnegie Mellon University
45 * All Rights Reserved.
49 * Permission to use, copy, modify and distribute this software and its
50 * documentation is hereby granted, provided that both the copyright
51 * notice and this permission notice appear in all copies of the
52 * software, derivative works or modified versions, and any portions
53 * thereof, and that both notices appear in supporting documentation.
55 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
56 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
57 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
59 * Carnegie Mellon requests users of this software to return to
61 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
62 * School of Computer Science
63 * Carnegie Mellon University
64 * Pittsburgh PA 15213-3890
66 * any improvements or extensions that they make and grant Carnegie the
67 * rights to redistribute these changes.
70 #include <sys/cdefs.h>
71 __FBSDID("$FreeBSD$");
74 * Stand-alone file reading package.
77 #include <sys/param.h>
78 #include <sys/disklabel.h>
80 #include <ufs/ufs/dinode.h>
81 #include <ufs/ufs/dir.h>
82 #include <ufs/ffs/fs.h>
87 static int ufs_open(const char *path, struct open_file *f);
88 static int ufs_write(struct open_file *f, const void *buf, size_t size,
90 static int ufs_close(struct open_file *f);
91 static int ufs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
92 static off_t ufs_seek(struct open_file *f, off_t offset, int where);
93 static int ufs_stat(struct open_file *f, struct stat *sb);
94 static int ufs_readdir(struct open_file *f, struct dirent *d);
95 static int ufs_mount(const char *dev, const char *path, void **data);
96 static int ufs_unmount(const char *dev, void *data);
98 struct fs_ops ufs_fsops = {
101 .fo_close = ufs_close,
103 .fo_write = ufs_write,
106 .fo_readdir = ufs_readdir,
107 .fo_mount = ufs_mount,
108 .fo_unmount = ufs_unmount
115 off_t f_seekp; /* seek pointer */
116 struct fs *f_fs; /* pointer to super-block */
118 struct ufs1_dinode di1;
119 struct ufs2_dinode di2;
120 } f_di; /* copy of on-disk inode */
121 int f_nindir[UFS_NIADDR];
122 /* number of blocks mapped by
123 indirect block at level i */
124 char *f_blk[UFS_NIADDR]; /* buffer for indirect block at
126 size_t f_blksize[UFS_NIADDR];
128 ufs2_daddr_t f_blkno[UFS_NIADDR];/* disk address of block in buffer */
129 ufs2_daddr_t f_buf_blkno; /* block number of data block */
130 char *f_buf; /* buffer for data block */
131 size_t f_buf_size; /* size of data block */
132 int f_inumber; /* inumber */
134 #define DIP(fp, field) \
135 ((fp)->f_fs->fs_magic == FS_UFS1_MAGIC ? \
136 (fp)->f_di.di1.field : (fp)->f_di.di2.field)
138 typedef struct ufs_mnt {
141 STAILQ_ENTRY(ufs_mnt) um_link;
144 typedef STAILQ_HEAD(ufs_mnt_list, ufs_mnt) ufs_mnt_list_t;
145 static ufs_mnt_list_t mnt_list = STAILQ_HEAD_INITIALIZER(mnt_list);
147 static int read_inode(ino_t, struct open_file *);
148 static int block_map(struct open_file *, ufs2_daddr_t, ufs2_daddr_t *);
149 static int buf_read_file(struct open_file *, char **, size_t *);
150 static int buf_write_file(struct open_file *, const char *, size_t *);
151 static int search_directory(char *, struct open_file *, ino_t *);
152 static int ufs_use_sa_read(void *, off_t, void **, int);
154 /* from ffs_subr.c */
155 int ffs_sbget(void *, struct fs **, off_t, int, char *,
156 int (*)(void *, off_t, void **, int));
159 * Read a new inode into a file structure.
162 read_inode(ino_t inumber, struct open_file *f)
164 struct file *fp = (struct file *)f->f_fsdata;
165 struct fs *fs = fp->f_fs;
174 * Read inode and save it.
176 buf = malloc(fs->fs_bsize);
178 rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
179 fsbtodb(fs, ino_to_fsba(fs, inumber)), fs->fs_bsize,
183 if (rsize != fs->fs_bsize) {
188 if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
189 fp->f_di.di1 = ((struct ufs1_dinode *)buf)
190 [ino_to_fsbo(fs, inumber)];
192 fp->f_di.di2 = ((struct ufs2_dinode *)buf)
193 [ino_to_fsbo(fs, inumber)];
196 * Clear out the old buffers
201 for (level = 0; level < UFS_NIADDR; level++)
202 fp->f_blkno[level] = -1;
203 fp->f_buf_blkno = -1;
206 fp->f_inumber = inumber;
213 * Given an offset in a file, find the disk block number that
214 * contains that block.
217 block_map(struct open_file *f, ufs2_daddr_t file_block,
218 ufs2_daddr_t *disk_block_p)
220 struct file *fp = (struct file *)f->f_fsdata;
221 struct fs *fs = fp->f_fs;
224 ufs2_daddr_t ind_block_num;
228 * Index structure of an inode:
230 * di_db[0..UFS_NDADDR-1] hold block numbers for blocks
233 * di_ib[0] index block 0 is the single indirect block
234 * holds block numbers for blocks
235 * UFS_NDADDR .. UFS_NDADDR + NINDIR(fs)-1
237 * di_ib[1] index block 1 is the double indirect block
238 * holds block numbers for INDEX blocks for blocks
239 * UFS_NDADDR + NINDIR(fs) ..
240 * UFS_NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
242 * di_ib[2] index block 2 is the triple indirect block
243 * holds block numbers for double-indirect
245 * UFS_NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
246 * UFS_NDADDR + NINDIR(fs) + NINDIR(fs)**2
247 * + NINDIR(fs)**3 - 1
250 if (file_block < UFS_NDADDR) {
252 *disk_block_p = DIP(fp, di_db[file_block]);
256 file_block -= UFS_NDADDR;
260 * nindir[1] = NINDIR**2
261 * nindir[2] = NINDIR**3
264 for (level = 0; level < UFS_NIADDR; level++) {
265 if (file_block < fp->f_nindir[level])
267 file_block -= fp->f_nindir[level];
269 if (level == UFS_NIADDR) {
270 /* Block number too high */
274 ind_block_num = DIP(fp, di_ib[level]);
276 for (; level >= 0; level--) {
277 if (ind_block_num == 0) {
278 *disk_block_p = 0; /* missing */
282 if (fp->f_blkno[level] != ind_block_num) {
283 if (fp->f_blk[level] == (char *)0)
285 malloc(fs->fs_bsize);
287 rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
288 fsbtodb(fp->f_fs, ind_block_num),
291 &fp->f_blksize[level]);
294 if (fp->f_blksize[level] != fs->fs_bsize)
296 fp->f_blkno[level] = ind_block_num;
300 idx = file_block / fp->f_nindir[level - 1];
301 file_block %= fp->f_nindir[level - 1];
305 if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
306 ind_block_num = ((ufs1_daddr_t *)fp->f_blk[level])[idx];
308 ind_block_num = ((ufs2_daddr_t *)fp->f_blk[level])[idx];
311 *disk_block_p = ind_block_num;
317 * Write a portion of a file from an internal buffer.
320 buf_write_file(struct open_file *f, const char *buf_p, size_t *size_p)
322 struct file *fp = (struct file *)f->f_fsdata;
323 struct fs *fs = fp->f_fs;
325 ufs_lbn_t file_block;
326 ufs2_daddr_t disk_block;
331 * Calculate the starting block address and offset.
333 off = blkoff(fs, fp->f_seekp);
334 file_block = lblkno(fs, fp->f_seekp);
335 block_size = sblksize(fs, DIP(fp, di_size), file_block);
337 rc = block_map(f, file_block, &disk_block);
342 /* Because we can't allocate space on the drive */
346 * Truncate buffer at end of file, and at the end of
349 if (*size_p > DIP(fp, di_size) - fp->f_seekp)
350 *size_p = DIP(fp, di_size) - fp->f_seekp;
351 if (*size_p > block_size - off)
352 *size_p = block_size - off;
355 * If we don't entirely occlude the block and it's not
356 * in memory already, read it in first.
358 if (((off > 0) || (*size_p + off < block_size)) &&
359 (file_block != fp->f_buf_blkno)) {
361 if (fp->f_buf == (char *)0)
362 fp->f_buf = malloc(fs->fs_bsize);
365 rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
366 fsbtodb(fs, disk_block),
367 block_size, fp->f_buf, &fp->f_buf_size);
371 fp->f_buf_blkno = file_block;
375 * Copy the user data into the cached block.
377 bcopy(buf_p, fp->f_buf + off, *size_p);
380 * Write the block out to storage.
384 rc = (f->f_dev->dv_strategy)(f->f_devdata, F_WRITE,
385 fsbtodb(fs, disk_block),
386 block_size, fp->f_buf, &fp->f_buf_size);
391 * Read a portion of a file into an internal buffer. Return
392 * the location in the buffer and the amount in the buffer.
395 buf_read_file(struct open_file *f, char **buf_p, size_t *size_p)
397 struct file *fp = (struct file *)f->f_fsdata;
398 struct fs *fs = fp->f_fs;
400 ufs_lbn_t file_block;
401 ufs2_daddr_t disk_block;
405 off = blkoff(fs, fp->f_seekp);
406 file_block = lblkno(fs, fp->f_seekp);
407 block_size = sblksize(fs, DIP(fp, di_size), file_block);
409 if (file_block != fp->f_buf_blkno) {
410 if (fp->f_buf == (char *)0)
411 fp->f_buf = malloc(fs->fs_bsize);
413 rc = block_map(f, file_block, &disk_block);
417 if (disk_block == 0) {
418 bzero(fp->f_buf, block_size);
419 fp->f_buf_size = block_size;
422 rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
423 fsbtodb(fs, disk_block),
424 block_size, fp->f_buf, &fp->f_buf_size);
429 fp->f_buf_blkno = file_block;
433 * Return address of byte in buffer corresponding to
434 * offset, and size of remainder of buffer after that
437 *buf_p = fp->f_buf + off;
438 *size_p = block_size - off;
441 * But truncate buffer at end of file.
443 if (*size_p > DIP(fp, di_size) - fp->f_seekp)
444 *size_p = DIP(fp, di_size) - fp->f_seekp;
450 * Search a directory for a name and return its
454 search_directory(char *name, struct open_file *f, ino_t *inumber_p)
456 struct file *fp = (struct file *)f->f_fsdata;
464 length = strlen(name);
467 while (fp->f_seekp < DIP(fp, di_size)) {
468 rc = buf_read_file(f, &buf, &buf_size);
472 dp = (struct direct *)buf;
473 edp = (struct direct *)(buf + buf_size);
475 if (dp->d_ino == (ino_t)0)
477 #if BYTE_ORDER == LITTLE_ENDIAN
478 if (fp->f_fs->fs_maxsymlinklen <= 0)
482 namlen = dp->d_namlen;
483 if (namlen == length &&
484 !strcmp(name, dp->d_name)) {
486 *inumber_p = dp->d_ino;
490 dp = (struct direct *)((char *)dp + dp->d_reclen);
492 fp->f_seekp += buf_size;
501 ufs_open(const char *upath, struct open_file *f)
505 ino_t inumber, parent_inumber;
510 char namebuf[MAXPATHLEN+1];
516 /* allocate file system specific data structure */
518 fp = calloc(1, sizeof(struct file));
521 f->f_fsdata = (void *)fp;
523 dev = disk_fmtdev(f->f_devdata);
524 /* Is this device mounted? */
525 STAILQ_FOREACH(mnt, &mnt_list, um_link) {
526 if (strcmp(dev, mnt->um_dev) == 0)
531 /* read super block */
533 if ((rc = ffs_sbget(f, &fs, UFS_STDSB, UFS_NOHASHFAIL, "stand",
534 ufs_use_sa_read)) != 0) {
538 struct open_file *sbf;
541 /* get superblock from mounted file system */
542 sbf = fd2open_file(mnt->um_fd);
549 * Calculate indirect block levels.
556 for (level = 0; level < UFS_NIADDR; level++) {
558 fp->f_nindir[level] = mult;
562 inumber = UFS_ROOTINO;
563 if ((rc = read_inode(inumber, f)) != 0)
566 cp = path = strdup(upath);
574 * Remove extra separators
582 * Check that current node is a directory.
584 if ((DIP(fp, di_mode) & IFMT) != IFDIR) {
590 * Get next component of path name.
596 while ((c = *cp) != '\0' && c != '/') {
597 if (++len > UFS_MAXNAMLEN) {
607 * Look up component in current directory.
608 * Save directory inumber in case we find a
611 parent_inumber = inumber;
612 rc = search_directory(ncp, f, &inumber);
618 * Open next component.
620 if ((rc = read_inode(inumber, f)) != 0)
624 * Check for symbolic link.
626 if ((DIP(fp, di_mode) & IFMT) == IFLNK) {
627 int link_len = DIP(fp, di_size);
632 if (link_len + len > MAXPATHLEN ||
633 ++nlinks > MAXSYMLINKS) {
638 bcopy(cp, &namebuf[link_len], len + 1);
640 if (link_len < fs->fs_maxsymlinklen) {
641 bcopy(DIP(fp, di_shortlink), namebuf,
642 (unsigned) link_len);
645 * Read file for symbolic link
648 ufs2_daddr_t disk_block;
649 struct fs *fs = fp->f_fs;
652 buf = malloc(fs->fs_bsize);
653 rc = block_map(f, (ufs2_daddr_t)0, &disk_block);
658 rc = (f->f_dev->dv_strategy)(f->f_devdata,
659 F_READ, fsbtodb(fs, disk_block),
660 fs->fs_bsize, buf, &buf_size);
664 bcopy((char *)buf, namebuf, (unsigned)link_len);
668 * If relative pathname, restart at parent directory.
669 * If absolute pathname, restart at root.
673 inumber = parent_inumber;
675 inumber = (ino_t)UFS_ROOTINO;
677 if ((rc = read_inode(inumber, f)) != 0)
683 * Found terminal component.
693 if (mnt == NULL && fp->f_fs != NULL) {
694 free(fp->f_fs->fs_csp);
695 free(fp->f_fs->fs_si);
704 * A read function for use by standalone-layer routines.
707 ufs_use_sa_read(void *devfd, off_t loc, void **bufp, int size)
713 f = (struct open_file *)devfd;
714 if ((*bufp = malloc(size)) == NULL)
716 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, loc / DEV_BSIZE,
717 size, *bufp, &buf_size);
720 if (buf_size != size)
726 ufs_close(struct open_file *f)
729 struct file *fp = (struct file *)f->f_fsdata;
737 for (level = 0; level < UFS_NIADDR; level++) {
738 free(fp->f_blk[level]);
742 dev = disk_fmtdev(f->f_devdata);
743 STAILQ_FOREACH(mnt, &mnt_list, um_link) {
744 if (strcmp(dev, mnt->um_dev) == 0)
748 if (mnt == NULL && fp->f_fs != NULL) {
749 free(fp->f_fs->fs_csp);
750 free(fp->f_fs->fs_si);
759 * Copy a portion of a file into kernel memory.
760 * Cross block boundaries when necessary.
763 ufs_read(struct open_file *f, void *start, size_t size, size_t *resid)
765 struct file *fp = (struct file *)f->f_fsdata;
773 if (fp->f_seekp >= DIP(fp, di_size))
776 rc = buf_read_file(f, &buf, &buf_size);
781 if (csize > buf_size)
784 bcopy(buf, addr, csize);
786 fp->f_seekp += csize;
796 * Write to a portion of an already allocated file.
797 * Cross block boundaries when necessary. Can not
801 ufs_write(struct open_file *f, const void *start, size_t size, size_t *resid)
803 struct file *fp = (struct file *)f->f_fsdata;
806 const char *addr = start;
809 while ((size != 0) && (csize != 0)) {
810 if (fp->f_seekp >= DIP(fp, di_size))
813 if (csize >= 512) csize = 512; /* XXX */
815 rc = buf_write_file(f, addr, &csize);
819 fp->f_seekp += csize;
829 ufs_seek(struct open_file *f, off_t offset, int where)
831 struct file *fp = (struct file *)f->f_fsdata;
835 fp->f_seekp = offset;
838 fp->f_seekp += offset;
841 fp->f_seekp = DIP(fp, di_size) - offset;
847 return (fp->f_seekp);
851 ufs_stat(struct open_file *f, struct stat *sb)
853 struct file *fp = (struct file *)f->f_fsdata;
855 /* only important stuff */
856 sb->st_mode = DIP(fp, di_mode);
857 sb->st_uid = DIP(fp, di_uid);
858 sb->st_gid = DIP(fp, di_gid);
859 sb->st_size = DIP(fp, di_size);
860 sb->st_mtime = DIP(fp, di_mtime);
862 * The items below are ufs specific!
863 * Other fs types will need their own solution
864 * if these fields are needed.
866 sb->st_ino = fp->f_inumber;
868 * We need something to differentiate devs.
869 * fs_id is unique but 64bit, we xor the two
870 * halves to squeeze it into 32bits.
872 sb->st_dev = (dev_t)(fp->f_fs->fs_id[0] ^ fp->f_fs->fs_id[1]);
878 ufs_readdir(struct open_file *f, struct dirent *d)
880 struct file *fp = (struct file *)f->f_fsdata;
887 * assume that a directory entry will not be split across blocks
890 if (fp->f_seekp >= DIP(fp, di_size))
892 error = buf_read_file(f, &buf, &buf_size);
895 dp = (struct direct *)buf;
896 fp->f_seekp += dp->d_reclen;
897 if (dp->d_ino == (ino_t)0)
899 d->d_type = dp->d_type;
900 strcpy(d->d_name, dp->d_name);
905 ufs_mount(const char *dev, const char *path, void **data)
912 mnt = calloc(1, sizeof(*mnt));
916 mnt->um_dev = strdup(dev);
917 if (mnt->um_dev == NULL)
920 if (asprintf(&fs, "%s%s", dev, path) < 0)
923 mnt->um_fd = open(fs, O_RDONLY);
925 if (mnt->um_fd == -1)
928 /* Is it ufs file system? */
929 f = fd2open_file(mnt->um_fd);
930 if (strcmp(f->f_ops->fs_name, "ufs") == 0)
931 STAILQ_INSERT_TAIL(&mnt_list, mnt, um_link);
949 ufs_unmount(const char *dev __unused, void *data)
951 ufs_mnt_t *mnt = data;
953 STAILQ_REMOVE(&mnt_list, mnt, ufs_mnt, um_link);