/* * Read a new inode into a file structure. */ static int read_inode(ino32_t inumber, struct open_file *f) { struct file *fp = (struct file *)f->f_fsdata; struct fs *fs = fp->f_fs; char *buf; size_t rsize; int rc; daddr_t inode_sector = 0; /* XXX: gcc */ #ifdef LIBSA_LFS struct ufs_dinode *dip; int cnt; #endif #ifdef LIBSA_LFS if (inumber == fs->lfs_ifile) inode_sector = FSBTODB(fs, fs->lfs_idaddr); else if ((rc = find_inode_sector(inumber, f, &inode_sector)) != 0) return rc; #else inode_sector = FSBTODB(fs, ino_to_fsba(fs, inumber)); #endif /* * Read inode and save it. */ buf = fp->f_buf; twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, inode_sector, fs->fs_bsize, buf, &rsize); if (rc) return rc; if (rsize != fs->fs_bsize) return EIO; #ifdef LIBSA_LFS cnt = INOPBx(fs); dip = (struct ufs_dinode *)buf + (cnt - 1); for (; dip->di_inumber != inumber; --dip) { /* kernel code panics, but boot blocks which panic are Bad. */ if (--cnt == 0) return EINVAL; } fp->f_di = *dip; #else fp->f_di = ((struct ufs_dinode *)buf)[ino_to_fsbo(fs, inumber)]; #endif /* * Clear out the old buffers */ fp->f_ind_cache_block = ~0; fp->f_buf_blkno = -1; return rc; }
int read_gdblock(struct open_file *f, struct m_ext2fs *fs) { struct file *fp = (struct file *)f->f_fsdata; size_t rsize; uint gdpb; int i, rc; gdpb = fs->e2fs_bsize / sizeof(struct ext2_gd); for (i = 0; i < fs->e2fs_ngdb; i++) { rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, fs->e2fs.e2fs_first_dblock + 1 /* superblock */ + i), fs->e2fs_bsize, fp->f_buf, &rsize); if (rc) return rc; if (rsize != fs->e2fs_bsize) return EIO; e2fs_cgload((struct ext2_gd *)fp->f_buf, &fs->e2fs_gd[i * gdpb], (i == (fs->e2fs_ngdb - 1)) ? (fs->e2fs_ncg - gdpb * i) * sizeof(struct ext2_gd): fs->e2fs_bsize); } return 0; }
/* * Find an inode's block. Look it up in the ifile. Whee! */ static int find_inode_sector(ino32_t inumber, struct open_file *f, daddr_t *isp) { struct file *fp = (struct file *)f->f_fsdata; struct fs *fs = fp->f_fs; daddr_t ifileent_blkno; char *ent_in_buf; size_t buf_after_ent; int rc; rc = read_inode(fs->lfs_ifile, f); if (rc) return rc; ifileent_blkno = (inumber / fs->lfs_ifpb) + fs->lfs_cleansz + fs->lfs_segtabsz; fp->f_seekp = (off_t)ifileent_blkno * fs->fs_bsize + (inumber % fs->lfs_ifpb) * sizeof (IFILE_Vx); rc = buf_read_file(f, &ent_in_buf, &buf_after_ent); if (rc) return rc; /* make sure something's not badly wrong, but don't panic. */ if (buf_after_ent < sizeof (IFILE_Vx)) return EINVAL; *isp = FSBTODB(fs, ((IFILE_Vx *)ent_in_buf)->if_daddr); if (*isp == LFS_UNUSED_DADDR) /* again, something badly wrong */ return EINVAL; return 0; }
/* * Read a portion of a file into an internal buffer. * Return the location in the buffer and the amount in the buffer. */ static int buf_read_file(struct open_file *f, char **buf_p, size_t *size_p) { struct file *fp = (struct file *)f->f_fsdata; struct fs *fs = fp->f_fs; long off; indp_t file_block; size_t block_size; int rc; off = ufs_blkoff(fs, fp->f_seekp); file_block = ufs_lblkno(fs, fp->f_seekp); #ifdef LIBSA_LFS block_size = dblksize(fs, &fp->f_di, file_block); #else block_size = ffs_sblksize(fs, (int64_t)fp->f_di.di_size, file_block); #endif if (file_block != fp->f_buf_blkno) { indp_t disk_block = 0; /* XXX: gcc */ rc = block_map(f, file_block, &disk_block); if (rc) return rc; if (disk_block == 0) { memset(fp->f_buf, 0, block_size); fp->f_buf_size = block_size; } else { twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, disk_block), block_size, fp->f_buf, &fp->f_buf_size); if (rc) return rc; } fp->f_buf_blkno = file_block; } /* * Return address of byte in buffer corresponding to * offset, and size of remainder of buffer after that * byte. */ *buf_p = fp->f_buf + off; *size_p = block_size - off; /* * But truncate buffer at end of file. */ if (*size_p > fp->f_di.di_size - fp->f_seekp) *size_p = fp->f_di.di_size - fp->f_seekp; return 0; }
/* * Read a portion of a file into an internal buffer. * Return the location in the buffer and the amount in the buffer. */ static int buf_read_file(struct open_file *f, char **buf_p, size_t *size_p) { struct file *fp = (struct file *)f->f_fsdata; struct m_ext2fs *fs = fp->f_fs; long off; indp_t file_block; indp_t disk_block = 0; /* XXX: gcc */ size_t block_size; int rc; off = ext2_blkoff(fs, fp->f_seekp); file_block = ext2_lblkno(fs, fp->f_seekp); block_size = fs->e2fs_bsize; /* no fragment */ if (file_block != fp->f_buf_blkno) { rc = block_map(f, file_block, &disk_block); if (rc) return rc; if (disk_block == 0) { memset(fp->f_buf, 0, block_size); fp->f_buf_size = block_size; } else { twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, disk_block), block_size, fp->f_buf, &fp->f_buf_size); if (rc) return rc; } fp->f_buf_blkno = file_block; } /* * Return address of byte in buffer corresponding to * offset, and size of remainder of buffer after that * byte. */ *buf_p = fp->f_buf + off; *size_p = block_size - off; /* * But truncate buffer at end of file. */ /* XXX should handle LARGEFILE */ if (*size_p > fp->f_di.e2di_size - fp->f_seekp) *size_p = fp->f_di.e2di_size - fp->f_seekp; return 0; }
/* * Read a portion of a file into an internal buffer. * Return the location in the buffer and the amount in the buffer. */ static int buf_read_file(struct open_file *f, void *v, size_t *size_p) { char **buf_p = v; struct file *fp = (struct file *)f->f_fsdata; struct mfs_sblock *fs = fp->f_fs; long off; block_t file_block; block_t disk_block; size_t block_size; int rc; off = mfs_blkoff(fs, fp->f_seekp); file_block = mfs_lblkno(fs, fp->f_seekp); block_size = fs->mfs_block_size; if (file_block != fp->f_buf_blkno) { rc = block_map(f, file_block, &disk_block); if (rc) return rc; if (disk_block == 0) { memset(fp->f_buf, 0, block_size); fp->f_buf_size = block_size; } else { twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, disk_block), block_size, fp->f_buf, &fp->f_buf_size); if (rc) return rc; } fp->f_buf_blkno = file_block; } /* * Return address of byte in buffer corresponding to * offset, and size of remainder of buffer after that * byte. */ *buf_p = fp->f_buf + off; *size_p = block_size - off; /* * But truncate buffer at end of file. */ if (*size_p > fp->f_di.mdi_size - fp->f_seekp) *size_p = fp->f_di.mdi_size - fp->f_seekp; return 0; }
/* * Read a new inode into a file structure. */ static int read_inode(ino32_t inumber, struct open_file *f) { struct file *fp = (struct file *)f->f_fsdata; struct m_ext2fs *fs = fp->f_fs; char *buf; size_t rsize; int rc; daddr_t inode_sector; struct ext2fs_dinode *dip; inode_sector = FSBTODB(fs, ino_to_fsba(fs, inumber)); /* * Read inode and save it. */ buf = fp->f_buf; twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, inode_sector, fs->e2fs_bsize, buf, &rsize); if (rc) return rc; if (rsize != fs->e2fs_bsize) return EIO; dip = (struct ext2fs_dinode *)(buf + EXT2_DINODE_SIZE(fs) * ino_to_fsbo(fs, inumber)); e2fs_iload(dip, &fp->f_di, EXT2_DINODE_SIZE(fs)); /* * Clear out the old buffers */ fp->f_ind_cache_block = ~0; fp->f_buf_blkno = -1; return rc; }
/* * Open a file. */ __compactcall int ufs_open(const char *path, struct open_file *f) { #ifndef LIBSA_FS_SINGLECOMPONENT const char *cp, *ncp; int c; #endif ino32_t inumber; struct file *fp; struct fs *fs; int rc; #ifndef LIBSA_NO_FS_SYMLINK ino32_t parent_inumber; int nlinks = 0; char namebuf[MAXPATHLEN+1]; char *buf; #endif /* allocate file system specific data structure */ fp = alloc(sizeof(struct file)); memset(fp, 0, sizeof(struct file)); f->f_fsdata = (void *)fp; /* allocate space and read super block */ fs = alloc(SBLOCKSIZE); fp->f_fs = fs; twiddle(); #ifdef LIBSA_FFSv2 rc = ffs_find_superblock(f, fs); if (rc) goto out; #else { size_t buf_size; rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, SBLOCKOFFSET / DEV_BSIZE, SBLOCKSIZE, fs, &buf_size); if (rc) goto out; if (buf_size != SBLOCKSIZE || #ifdef LIBSA_FFS fs->lfs_version != REQUIRED_LFS_VERSION || #endif fs->fs_magic != FS_MAGIC) { rc = EINVAL; goto out; } } #if defined(LIBSA_LFS) && REQUIRED_LFS_VERSION == 2 /* * XXX We should check the second superblock and use the eldest * of the two. See comments near the top of lfs_mountfs() * in sys/ufs/lfs/lfs_vfsops.c. * This may need a LIBSA_LFS_SMALL check as well. */ #endif #endif #ifdef LIBSA_FFSv1 ffs_oldfscompat(fs); #endif if (fs->fs_bsize > MAXBSIZE || (size_t)fs->fs_bsize < sizeof(struct fs)) { rc = EINVAL; goto out; } /* * Calculate indirect block levels. */ { indp_t mult; int ln2; /* * We note that the number of indirect blocks is always * a power of 2. This lets us use shifts and masks instead * of divide and remainder and avoinds pulling in the * 64bit division routine into the boot code. */ mult = UFS_NINDIR(fs); #ifdef DEBUG if (mult & (mult - 1)) { /* Hummm was't a power of 2 */ rc = EINVAL; goto out; } #endif for (ln2 = 0; mult != 1; ln2++) mult >>= 1; fp->f_nishift = ln2; } /* alloc a block sized buffer used for all fs transfers */ fp->f_buf = alloc(fs->fs_bsize); inumber = UFS_ROOTINO; if ((rc = read_inode(inumber, f)) != 0) goto out; #ifndef LIBSA_FS_SINGLECOMPONENT cp = path; while (*cp) { /* * Remove extra separators */ while (*cp == '/') cp++; if (*cp == '\0') break; /* * Check that current node is a directory. */ if ((fp->f_di.di_mode & IFMT) != IFDIR) { rc = ENOTDIR; goto out; } /* * Get next component of path name. */ ncp = cp; while ((c = *cp) != '\0' && c != '/') cp++; /* * Look up component in current directory. * Save directory inumber in case we find a * symbolic link. */ #ifndef LIBSA_NO_FS_SYMLINK parent_inumber = inumber; #endif rc = search_directory(ncp, cp - ncp, f, &inumber); if (rc) goto out; /* * Open next component. */ if ((rc = read_inode(inumber, f)) != 0) goto out; #ifndef LIBSA_NO_FS_SYMLINK /* * Check for symbolic link. */ if ((fp->f_di.di_mode & IFMT) == IFLNK) { int link_len = fp->f_di.di_size; int len; len = strlen(cp); if (link_len + len > MAXPATHLEN || ++nlinks > MAXSYMLINKS) { rc = ENOENT; goto out; } memmove(&namebuf[link_len], cp, len + 1); if (link_len < fs->fs_maxsymlinklen) { memcpy(namebuf, fp->f_di.di_db, link_len); } else { /* * Read file for symbolic link */ size_t buf_size; indp_t disk_block; buf = fp->f_buf; rc = block_map(f, (indp_t)0, &disk_block); if (rc) goto out; twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, disk_block), fs->fs_bsize, buf, &buf_size); if (rc) goto out; memcpy(namebuf, buf, link_len); } /* * If relative pathname, restart at parent directory. * If absolute pathname, restart at root. */ cp = namebuf; if (*cp != '/') inumber = parent_inumber; else inumber = (ino32_t)UFS_ROOTINO; if ((rc = read_inode(inumber, f)) != 0) goto out; } #endif /* !LIBSA_NO_FS_SYMLINK */ } /* * Found terminal component. */ rc = 0; #else /* !LIBSA_FS_SINGLECOMPONENT */ /* look up component in the current (root) directory */ rc = search_directory(path, strlen(path), f, &inumber); if (rc) goto out; /* open it */ rc = read_inode(inumber, f); #endif /* !LIBSA_FS_SINGLECOMPONENT */ fp->f_seekp = 0; /* reset seek pointer */ out: if (rc) ufs_close(f); #ifdef FSMOD /* Only defined for lfs */ else fsmod = FSMOD; #endif return rc; }
/* * Given an offset in a file, find the disk block number that * contains that block. */ static int block_map(struct open_file *f, indp_t file_block, indp_t *disk_block_p) { struct file *fp = (struct file *)f->f_fsdata; struct fs *fs = fp->f_fs; uint level; indp_t ind_cache; indp_t ind_block_num; size_t rsize; int rc; indp_t *buf = (void *)fp->f_buf; /* * Index structure of an inode: * * di_db[0..UFS_NDADDR-1] hold block numbers for blocks * 0..UFS_NDADDR-1 * * di_ib[0] index block 0 is the single indirect block * holds block numbers for blocks * UFS_NDADDR .. UFS_NDADDR + UFS_NINDIR(fs)-1 * * di_ib[1] index block 1 is the double indirect block * holds block numbers for INDEX blocks for blocks * UFS_NDADDR + UFS_NINDIR(fs) .. * UFS_NDADDR + UFS_NINDIR(fs) + UFS_NINDIR(fs)**2 - 1 * * di_ib[2] index block 2 is the triple indirect block * holds block numbers for double-indirect * blocks for blocks * UFS_NDADDR + UFS_NINDIR(fs) + UFS_NINDIR(fs)**2 .. * UFS_NDADDR + UFS_NINDIR(fs) + UFS_NINDIR(fs)**2 * + UFS_NINDIR(fs)**3 - 1 */ if (file_block < UFS_NDADDR) { /* Direct block. */ *disk_block_p = fp->f_di.di_db[file_block]; return 0; } file_block -= UFS_NDADDR; ind_cache = file_block >> LN2_IND_CACHE_SZ; if (ind_cache == fp->f_ind_cache_block) { *disk_block_p = fp->f_ind_cache[file_block & IND_CACHE_MASK]; return 0; } for (level = 0;;) { level += fp->f_nishift; if (file_block < (indp_t)1 << level) break; if (level > UFS_NIADDR * fp->f_nishift) /* Block number too high */ return EFBIG; file_block -= (indp_t)1 << level; } ind_block_num = fp->f_di.di_ib[level / fp->f_nishift - 1]; for (;;) { level -= fp->f_nishift; if (ind_block_num == 0) { *disk_block_p = 0; /* missing */ return 0; } twiddle(); /* * If we were feeling brave, we could work out the number * of the disk sector and read a single disk sector instead * of a filesystem block. * However we don't do this very often anyway... */ rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fp->f_fs, ind_block_num), fs->fs_bsize, buf, &rsize); if (rc) return rc; if (rsize != fs->fs_bsize) return EIO; ind_block_num = buf[file_block >> level]; if (level == 0) break; file_block &= (1 << level) - 1; } /* Save the part of the block that contains this sector */ memcpy(fp->f_ind_cache, &buf[file_block & ~IND_CACHE_MASK], IND_CACHE_SZ * sizeof fp->f_ind_cache[0]); fp->f_ind_cache_block = ind_cache; *disk_block_p = ind_block_num; return 0; }
/* * Open a file. */ __compactcall int ext2fs_open(const char *path, struct open_file *f) { #ifndef LIBSA_FS_SINGLECOMPONENT const char *cp, *ncp; int c; #endif ino32_t inumber; struct file *fp; struct m_ext2fs *fs; int rc; #ifndef LIBSA_NO_FS_SYMLINK ino32_t parent_inumber; int nlinks = 0; char namebuf[MAXPATHLEN+1]; char *buf; #endif /* allocate file system specific data structure */ fp = alloc(sizeof(struct file)); memset(fp, 0, sizeof(struct file)); f->f_fsdata = (void *)fp; /* allocate space and read super block */ fs = alloc(sizeof(*fs)); memset(fs, 0, sizeof(*fs)); fp->f_fs = fs; twiddle(); rc = read_sblock(f, fs); if (rc) goto out; #ifdef EXT2FS_DEBUG dump_sblock(fs); #endif /* alloc a block sized buffer used for all fs transfers */ fp->f_buf = alloc(fs->e2fs_bsize); /* read group descriptor blocks */ fs->e2fs_gd = alloc(sizeof(struct ext2_gd) * fs->e2fs_ncg); rc = read_gdblock(f, fs); if (rc) goto out; /* * Calculate indirect block levels. */ { indp_t mult; int ln2; /* * We note that the number of indirect blocks is always * a power of 2. This lets us use shifts and masks instead * of divide and remainder and avoinds pulling in the * 64bit division routine into the boot code. */ mult = EXT2_NINDIR(fs); #ifdef DEBUG if (!powerof2(mult)) { /* Hummm was't a power of 2 */ rc = EINVAL; goto out; } #endif for (ln2 = 0; mult != 1; ln2++) mult >>= 1; fp->f_nishift = ln2; } inumber = EXT2_ROOTINO; if ((rc = read_inode(inumber, f)) != 0) goto out; #ifndef LIBSA_FS_SINGLECOMPONENT cp = path; while (*cp) { /* * Remove extra separators */ while (*cp == '/') cp++; if (*cp == '\0') break; /* * Check that current node is a directory. */ if ((fp->f_di.e2di_mode & EXT2_IFMT) != EXT2_IFDIR) { rc = ENOTDIR; goto out; } /* * Get next component of path name. */ ncp = cp; while ((c = *cp) != '\0' && c != '/') cp++; /* * Look up component in current directory. * Save directory inumber in case we find a * symbolic link. */ #ifndef LIBSA_NO_FS_SYMLINK parent_inumber = inumber; #endif rc = search_directory(ncp, cp - ncp, f, &inumber); if (rc) goto out; /* * Open next component. */ if ((rc = read_inode(inumber, f)) != 0) goto out; #ifndef LIBSA_NO_FS_SYMLINK /* * Check for symbolic link. */ if ((fp->f_di.e2di_mode & EXT2_IFMT) == EXT2_IFLNK) { /* XXX should handle LARGEFILE */ int link_len = fp->f_di.e2di_size; int len; len = strlen(cp); if (link_len + len > MAXPATHLEN || ++nlinks > MAXSYMLINKS) { rc = ENOENT; goto out; } memmove(&namebuf[link_len], cp, len + 1); if (link_len < EXT2_MAXSYMLINKLEN) { memcpy(namebuf, fp->f_di.e2di_blocks, link_len); } else { /* * Read file for symbolic link */ size_t buf_size; indp_t disk_block; buf = fp->f_buf; rc = block_map(f, (indp_t)0, &disk_block); if (rc) goto out; twiddle(); rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, disk_block), fs->e2fs_bsize, buf, &buf_size); if (rc) goto out; memcpy(namebuf, buf, link_len); } /* * If relative pathname, restart at parent directory. * If absolute pathname, restart at root. */ cp = namebuf; if (*cp != '/') inumber = parent_inumber; else inumber = (ino32_t)EXT2_ROOTINO; if ((rc = read_inode(inumber, f)) != 0) goto out; } #endif /* !LIBSA_NO_FS_SYMLINK */ } /* * Found terminal component. */ rc = 0; #else /* !LIBSA_FS_SINGLECOMPONENT */ /* look up component in the current (root) directory */ rc = search_directory(path, strlen(path), f, &inumber); if (rc) goto out; /* open it */ rc = read_inode(inumber, f); #endif /* !LIBSA_FS_SINGLECOMPONENT */ fp->f_seekp = 0; /* reset seek pointer */ out: if (rc) ext2fs_close(f); else fsmod = "ext2fs"; return rc; }
/* * Given an offset in a file, find the disk block number (not zone!) * that contains that block. */ static int block_map(struct open_file *f, block_t file_block, block_t *disk_block_p) { struct file *fp = (struct file *)f->f_fsdata; struct mfs_sblock *fs = fp->f_fs; uint level; block_t ind_cache; block_t ind_block_num; zone_t zone; size_t rsize; int rc; int boff; int scale = fs->mfs_log_zone_size; /* for block-zone conversion */ block_t *buf = (void *)fp->f_buf; /* * Index structure of an inode: * * mdi_blocks[0..NR_DZONES-1] * hold zone numbers for zones * 0..NR_DZONES-1 * * mdi_blocks[NR_DZONES+0] * block NDADDR+0 is the single indirect block * holds zone numbers for zones * NR_DZONES .. NR_DZONES + MFS_NINDIR(fs)-1 * * mdi_blocks[NR_DZONES+1] * block NDADDR+1 is the double indirect block * holds zone numbers for INDEX blocks for zones * NR_DZONES + MFS_NINDIR(fs) .. * NR_TZONES + MFS_NINDIR(fs) + MFS_NINDIR(fs)**2 - 1 */ zone = file_block >> scale; boff = (int) (file_block - (zone << scale) ); /* relative blk in zone */ if (zone < NR_DZONES) { /* Direct zone */ zone_t z = fs2h32(fp->f_di.mdi_zone[zone]); if (z == NO_ZONE) { *disk_block_p = NO_BLOCK; return 0; } *disk_block_p = (block_t) ((z << scale) + boff); return 0; } zone -= NR_DZONES; ind_cache = zone >> LN2_IND_CACHE_SZ; if (ind_cache == fp->f_ind_cache_block) { *disk_block_p = fs2h32(fp->f_ind_cache[zone & IND_CACHE_MASK]); return 0; } for (level = 0;;) { level += fp->f_nishift; if (zone < (block_t)1 << level) break; if (level > NIADDR * fp->f_nishift) /* Zone number too high */ return EFBIG; zone -= (block_t)1 << level; } ind_block_num = fs2h32(fp->f_di.mdi_zone[NR_DZONES + (level / fp->f_nishift - 1)]); for (;;) { level -= fp->f_nishift; if (ind_block_num == 0) { *disk_block_p = NO_BLOCK; /* missing */ return 0; } twiddle(); /* * If we were feeling brave, we could work out the number * of the disk sector and read a single disk sector instead * of a filesystem block. * However we don't do this very often anyway... */ rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, FSBTODB(fs, ind_block_num), fs->mfs_block_size, buf, &rsize); if (rc) return rc; if (rsize != fs->mfs_block_size) return EIO; ind_block_num = fs2h32(buf[zone >> level]); if (level == 0) break; zone &= (1 << level) - 1; } /* Save the part of the block that contains this sector */ memcpy(fp->f_ind_cache, &buf[zone & ~IND_CACHE_MASK], IND_CACHE_SZ * sizeof fp->f_ind_cache[0]); fp->f_ind_cache_block = ind_cache; zone = (zone_t)ind_block_num; *disk_block_p = (block_t)((zone << scale) + boff); return 0; }