/* * linux/fs/minix/inode.c * * Copyright (C) 1991, 1992 Linus Torvalds * * Copyright (C) 1996 Gertjan van Wingerde (gertjan@cs.vu.nl) * Minix V2 fs support. * * Modified for 680x0 by Andreas Schwab */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include static void minix_read_inode(struct inode * inode); static void minix_write_inode(struct inode * inode, int wait); static int minix_statfs(struct super_block *sb, struct statfs *buf); static int minix_remount (struct super_block * sb, int * flags, char * data); static void minix_delete_inode(struct inode *inode) { lock_kernel(); inode->i_size = 0; minix_truncate(inode); minix_free_inode(inode); unlock_kernel(); } static void minix_commit_super(struct super_block * sb) { mark_buffer_dirty(sb->u.minix_sb.s_sbh); sb->s_dirt = 0; } static void minix_write_super(struct super_block * sb) { struct minix_super_block * ms; if (!(sb->s_flags & MS_RDONLY)) { ms = sb->u.minix_sb.s_ms; if (ms->s_state & MINIX_VALID_FS) ms->s_state &= ~MINIX_VALID_FS; minix_commit_super(sb); } sb->s_dirt = 0; } static void minix_put_super(struct super_block *sb) { int i; if (!(sb->s_flags & MS_RDONLY)) { sb->u.minix_sb.s_ms->s_state = sb->u.minix_sb.s_mount_state; mark_buffer_dirty(sb->u.minix_sb.s_sbh); } for (i = 0; i < sb->u.minix_sb.s_imap_blocks; i++) brelse(sb->u.minix_sb.s_imap[i]); for (i = 0; i < sb->u.minix_sb.s_zmap_blocks; i++) brelse(sb->u.minix_sb.s_zmap[i]); brelse (sb->u.minix_sb.s_sbh); kfree(sb->u.minix_sb.s_imap); return; } static struct super_operations minix_sops = { read_inode: minix_read_inode, write_inode: minix_write_inode, delete_inode: minix_delete_inode, put_super: minix_put_super, write_super: minix_write_super, statfs: minix_statfs, remount_fs: minix_remount, }; static int minix_remount (struct super_block * sb, int * flags, char * data) { struct minix_super_block * ms; ms = sb->u.minix_sb.s_ms; if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) return 0; if (*flags & MS_RDONLY) { if (ms->s_state & MINIX_VALID_FS || !(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS)) return 0; /* Mounting a rw partition read-only. */ ms->s_state = sb->u.minix_sb.s_mount_state; mark_buffer_dirty(sb->u.minix_sb.s_sbh); sb->s_dirt = 1; minix_commit_super(sb); } else { /* Mount a partition which is read-only, read-write. */ sb->u.minix_sb.s_mount_state = ms->s_state; ms->s_state &= ~MINIX_VALID_FS; mark_buffer_dirty(sb->u.minix_sb.s_sbh); sb->s_dirt = 1; if (!(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS)) printk ("MINIX-fs warning: remounting unchecked fs, " "running fsck is recommended.\n"); else if ((sb->u.minix_sb.s_mount_state & MINIX_ERROR_FS)) printk ("MINIX-fs warning: remounting fs with errors, " "running fsck is recommended.\n"); } return 0; } /* * Check the root directory of the filesystem to make sure * it really _is_ a Minix filesystem, and to check the size * of the directory entry. */ static const char * minix_checkroot(struct super_block *s, struct inode *dir) { struct buffer_head *bh; struct minix_dir_entry *de; const char * errmsg; int dirsize; if (!S_ISDIR(dir->i_mode)) return "root directory is not a directory"; bh = minix_bread(dir, 0, 0); if (!bh) return "unable to read root directory"; de = (struct minix_dir_entry *) bh->b_data; errmsg = "bad root directory '.' entry"; dirsize = BLOCK_SIZE; if (de->inode == MINIX_ROOT_INO && strcmp(de->name, ".") == 0) { errmsg = "bad root directory '..' entry"; dirsize = 8; } while ((dirsize <<= 1) < BLOCK_SIZE) { de = (struct minix_dir_entry *) (bh->b_data + dirsize); if (de->inode != MINIX_ROOT_INO) continue; if (strcmp(de->name, "..")) continue; s->u.minix_sb.s_dirsize = dirsize; s->u.minix_sb.s_namelen = dirsize - 2; errmsg = NULL; break; } brelse(bh); return errmsg; } static struct super_block *minix_read_super(struct super_block *s, void *data, int silent) { struct buffer_head *bh; struct buffer_head **map; struct minix_super_block *ms; int i, block; kdev_t dev = s->s_dev; const char * errmsg; struct inode *root_inode; unsigned int hblock; /* N.B. These should be compile-time tests. Unfortunately that is impossible. */ if (32 != sizeof (struct minix_inode)) panic("bad V1 i-node size"); if (64 != sizeof(struct minix2_inode)) panic("bad V2 i-node size"); hblock = get_hardblocksize(dev); if (hblock && hblock > BLOCK_SIZE) goto out_bad_hblock; set_blocksize(dev, BLOCK_SIZE); if (!(bh = bread(dev,1,BLOCK_SIZE))) goto out_bad_sb; ms = (struct minix_super_block *) bh->b_data; s->u.minix_sb.s_ms = ms; s->u.minix_sb.s_sbh = bh; s->u.minix_sb.s_mount_state = ms->s_state; s->s_blocksize = BLOCK_SIZE; s->s_blocksize_bits = BLOCK_SIZE_BITS; s->u.minix_sb.s_ninodes = ms->s_ninodes; s->u.minix_sb.s_nzones = ms->s_nzones; s->u.minix_sb.s_imap_blocks = ms->s_imap_blocks; s->u.minix_sb.s_zmap_blocks = ms->s_zmap_blocks; s->u.minix_sb.s_firstdatazone = ms->s_firstdatazone; s->u.minix_sb.s_log_zone_size = ms->s_log_zone_size; s->u.minix_sb.s_max_size = ms->s_max_size; s->s_magic = ms->s_magic; if (s->s_magic == MINIX_SUPER_MAGIC) { s->u.minix_sb.s_version = MINIX_V1; s->u.minix_sb.s_dirsize = 16; s->u.minix_sb.s_namelen = 14; s->u.minix_sb.s_link_max = MINIX_LINK_MAX; } else if (s->s_magic == MINIX_SUPER_MAGIC2) { s->u.minix_sb.s_version = MINIX_V1; s->u.minix_sb.s_dirsize = 32; s->u.minix_sb.s_namelen = 30; s->u.minix_sb.s_link_max = MINIX_LINK_MAX; } else if (s->s_magic == MINIX2_SUPER_MAGIC) { s->u.minix_sb.s_version = MINIX_V2; s->u.minix_sb.s_nzones = ms->s_zones; s->u.minix_sb.s_dirsize = 16; s->u.minix_sb.s_namelen = 14; s->u.minix_sb.s_link_max = MINIX2_LINK_MAX; } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { s->u.minix_sb.s_version = MINIX_V2; s->u.minix_sb.s_nzones = ms->s_zones; s->u.minix_sb.s_dirsize = 32; s->u.minix_sb.s_namelen = 30; s->u.minix_sb.s_link_max = MINIX2_LINK_MAX; } else goto out_no_fs; /* * Allocate the buffer map to keep the superblock small. */ i = (s->u.minix_sb.s_imap_blocks + s->u.minix_sb.s_zmap_blocks) * sizeof(bh); map = kmalloc(i, GFP_KERNEL); if (!map) goto out_no_map; memset(map, 0, i); s->u.minix_sb.s_imap = &map[0]; s->u.minix_sb.s_zmap = &map[s->u.minix_sb.s_imap_blocks]; block=2; for (i=0 ; i < s->u.minix_sb.s_imap_blocks ; i++) { if (!(s->u.minix_sb.s_imap[i]=bread(dev,block,BLOCK_SIZE))) goto out_no_bitmap; block++; } for (i=0 ; i < s->u.minix_sb.s_zmap_blocks ; i++) { if (!(s->u.minix_sb.s_zmap[i]=bread(dev,block,BLOCK_SIZE))) goto out_no_bitmap; block++; } minix_set_bit(0,s->u.minix_sb.s_imap[0]->b_data); minix_set_bit(0,s->u.minix_sb.s_zmap[0]->b_data); s->s_maxbytes = MAX_NON_LFS; /* set up enough so that it can read an inode */ s->s_op = &minix_sops; root_inode = iget(s, MINIX_ROOT_INO); if (!root_inode) goto out_no_root; /* * Check the fs before we get the root dentry ... */ errmsg = minix_checkroot(s, root_inode); if (errmsg) goto out_bad_root; s->s_root = d_alloc_root(root_inode); if (!s->s_root) goto out_iput; s->s_root->d_op = &minix_dentry_operations; if (!(s->s_flags & MS_RDONLY)) { ms->s_state &= ~MINIX_VALID_FS; mark_buffer_dirty(bh); s->s_dirt = 1; } if (!(s->u.minix_sb.s_mount_state & MINIX_VALID_FS)) printk ("MINIX-fs: mounting unchecked file system, " "running fsck is recommended.\n"); else if (s->u.minix_sb.s_mount_state & MINIX_ERROR_FS) printk ("MINIX-fs: mounting file system with errors, " "running fsck is recommended.\n"); return s; out_bad_root: if (!silent) printk("MINIX-fs: %s\n", errmsg); out_iput: iput(root_inode); goto out_freemap; out_no_root: if (!silent) printk("MINIX-fs: get root inode failed\n"); goto out_freemap; out_no_bitmap: printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); out_freemap: for (i = 0; i < s->u.minix_sb.s_imap_blocks; i++) brelse(s->u.minix_sb.s_imap[i]); for (i = 0; i < s->u.minix_sb.s_zmap_blocks; i++) brelse(s->u.minix_sb.s_zmap[i]); kfree(s->u.minix_sb.s_imap); goto out_release; out_no_map: if (!silent) printk ("MINIX-fs: can't allocate map\n"); goto out_release; out_no_fs: if (!silent) printk("VFS: Can't find a Minix or Minix V2 filesystem on device " "%s.\n", kdevname(dev)); out_release: brelse(bh); goto out; out_bad_hblock: printk("MINIX-fs: blocksize too small for device.\n"); goto out; out_bad_sb: printk("MINIX-fs: unable to read superblock\n"); out: return NULL; } static int minix_statfs(struct super_block *sb, struct statfs *buf) { buf->f_type = sb->s_magic; buf->f_bsize = sb->s_blocksize; buf->f_blocks = (sb->u.minix_sb.s_nzones - sb->u.minix_sb.s_firstdatazone) << sb->u.minix_sb.s_log_zone_size; buf->f_bfree = minix_count_free_blocks(sb); buf->f_bavail = buf->f_bfree; buf->f_files = sb->u.minix_sb.s_ninodes; buf->f_ffree = minix_count_free_inodes(sb); buf->f_namelen = sb->u.minix_sb.s_namelen; return 0; } static int minix_get_block(struct inode *inode, long block, struct buffer_head *bh_result, int create) { if (INODE_VERSION(inode) == MINIX_V1) return V1_minix_get_block(inode, block, bh_result, create); else return V2_minix_get_block(inode, block, bh_result, create); } /* * the global minix fs getblk function. */ struct buffer_head *minix_getblk(struct inode *inode, int block, int create) { struct buffer_head dummy; int error; dummy.b_state = 0; dummy.b_blocknr = -1000; error = minix_get_block(inode, block, &dummy, create); if (!error && buffer_mapped(&dummy)) { struct buffer_head *bh; bh = getblk(dummy.b_dev, dummy.b_blocknr, BLOCK_SIZE); if (buffer_new(&dummy)) { memset(bh->b_data, 0, BLOCK_SIZE); mark_buffer_uptodate(bh, 1); mark_buffer_dirty(bh); } return bh; } return NULL; } struct buffer_head * minix_bread(struct inode * inode, int block, int create) { struct buffer_head * bh; bh = minix_getblk(inode, block, create); if (!bh || buffer_uptodate(bh)) return bh; ll_rw_block(READ, 1, &bh); wait_on_buffer(bh); if (buffer_uptodate(bh)) return bh; brelse(bh); return NULL; } static int minix_writepage(struct page *page) { return block_write_full_page(page,minix_get_block); } static int minix_readpage(struct file *file, struct page *page) { return block_read_full_page(page,minix_get_block); } static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) { return block_prepare_write(page,from,to,minix_get_block); } static int minix_bmap(struct address_space *mapping, long block) { return generic_block_bmap(mapping,block,minix_get_block); } struct address_space_operations minix_aops = { readpage: minix_readpage, writepage: minix_writepage, sync_page: block_sync_page, prepare_write: minix_prepare_write, commit_write: generic_commit_write, bmap: minix_bmap }; /* * The minix V1 function to read an inode. */ static void V1_minix_read_inode(struct inode * inode) { struct buffer_head * bh; struct minix_inode * raw_inode; int block, ino; ino = inode->i_ino; inode->i_mode = 0; if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) { printk("Bad inode number on dev %s" ": %d is out of range\n", kdevname(inode->i_dev), ino); return; } block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks + (ino-1)/MINIX_INODES_PER_BLOCK; if (!(bh=bread(inode->i_dev,block, BLOCK_SIZE))) { printk("Major problem: unable to read inode from dev " "%s\n", kdevname(inode->i_dev)); return; } raw_inode = ((struct minix_inode *) bh->b_data) + (ino-1)%MINIX_INODES_PER_BLOCK; inode->i_mode = raw_inode->i_mode; inode->i_uid = (uid_t)raw_inode->i_uid; inode->i_gid = (gid_t)raw_inode->i_gid; inode->i_nlink = raw_inode->i_nlinks; inode->i_size = raw_inode->i_size; inode->i_mtime = inode->i_atime = inode->i_ctime = raw_inode->i_time; inode->i_blocks = inode->i_blksize = 0; for (block = 0; block < 9; block++) inode->u.minix_i.u.i1_data[block] = raw_inode->i_zone[block]; if (S_ISREG(inode->i_mode)) { inode->i_op = &minix_file_inode_operations; inode->i_fop = &minix_file_operations; inode->i_mapping->a_ops = &minix_aops; } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &minix_dir_inode_operations; inode->i_fop = &minix_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; inode->i_mapping->a_ops = &minix_aops; } else init_special_inode(inode, inode->i_mode, raw_inode->i_zone[0]); brelse(bh); } /* * The minix V2 function to read an inode. */ static void V2_minix_read_inode(struct inode * inode) { struct buffer_head * bh; struct minix2_inode * raw_inode; int block, ino; ino = inode->i_ino; inode->i_mode = 0; if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) { printk("Bad inode number on dev %s" ": %d is out of range\n", kdevname(inode->i_dev), ino); return; } block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks + (ino-1)/MINIX2_INODES_PER_BLOCK; if (!(bh=bread(inode->i_dev,block, BLOCK_SIZE))) { printk("Major problem: unable to read inode from dev " "%s\n", kdevname(inode->i_dev)); return; } raw_inode = ((struct minix2_inode *) bh->b_data) + (ino-1)%MINIX2_INODES_PER_BLOCK; inode->i_mode = raw_inode->i_mode; inode->i_uid = (uid_t)raw_inode->i_uid; inode->i_gid = (gid_t)raw_inode->i_gid; inode->i_nlink = raw_inode->i_nlinks; inode->i_size = raw_inode->i_size; inode->i_mtime = raw_inode->i_mtime; inode->i_atime = raw_inode->i_atime; inode->i_ctime = raw_inode->i_ctime; inode->i_blocks = inode->i_blksize = 0; for (block = 0; block < 10; block++) inode->u.minix_i.u.i2_data[block] = raw_inode->i_zone[block]; if (S_ISREG(inode->i_mode)) { inode->i_op = &minix_file_inode_operations; inode->i_fop = &minix_file_operations; inode->i_mapping->a_ops = &minix_aops; } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &minix_dir_inode_operations; inode->i_fop = &minix_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; inode->i_mapping->a_ops = &minix_aops; } else init_special_inode(inode, inode->i_mode, raw_inode->i_zone[0]); brelse(bh); } /* * The global function to read an inode. */ static void minix_read_inode(struct inode * inode) { if (INODE_VERSION(inode) == MINIX_V1) V1_minix_read_inode(inode); else V2_minix_read_inode(inode); } /* * The minix V1 function to synchronize an inode. */ static struct buffer_head * V1_minix_update_inode(struct inode * inode) { struct buffer_head * bh; struct minix_inode * raw_inode; int ino, block; ino = inode->i_ino; if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) { printk("Bad inode number on dev %s" ": %d is out of range\n", kdevname(inode->i_dev), ino); return 0; } block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks + (ino-1)/MINIX_INODES_PER_BLOCK; if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE))) { printk("unable to read i-node block\n"); return 0; } raw_inode = ((struct minix_inode *)bh->b_data) + (ino-1)%MINIX_INODES_PER_BLOCK; raw_inode->i_mode = inode->i_mode; raw_inode->i_uid = fs_high2lowuid(inode->i_uid); raw_inode->i_gid = fs_high2lowgid(inode->i_gid); raw_inode->i_nlinks = inode->i_nlink; raw_inode->i_size = inode->i_size; raw_inode->i_time = inode->i_mtime; if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev); else for (block = 0; block < 9; block++) raw_inode->i_zone[block] = inode->u.minix_i.u.i1_data[block]; mark_buffer_dirty(bh); return bh; } /* * The minix V2 function to synchronize an inode. */ static struct buffer_head * V2_minix_update_inode(struct inode * inode) { struct buffer_head * bh; struct minix2_inode * raw_inode; int ino, block; ino = inode->i_ino; if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) { printk("Bad inode number on dev %s" ": %d is out of range\n", kdevname(inode->i_dev), ino); return 0; } block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks + (ino-1)/MINIX2_INODES_PER_BLOCK; if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE))) { printk("unable to read i-node block\n"); return 0; } raw_inode = ((struct minix2_inode *)bh->b_data) + (ino-1)%MINIX2_INODES_PER_BLOCK; raw_inode->i_mode = inode->i_mode; raw_inode->i_uid = fs_high2lowuid(inode->i_uid); raw_inode->i_gid = fs_high2lowgid(inode->i_gid); raw_inode->i_nlinks = inode->i_nlink; raw_inode->i_size = inode->i_size; raw_inode->i_mtime = inode->i_mtime; raw_inode->i_atime = inode->i_atime; raw_inode->i_ctime = inode->i_ctime; if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev); else for (block = 0; block < 10; block++) raw_inode->i_zone[block] = inode->u.minix_i.u.i2_data[block]; mark_buffer_dirty(bh); return bh; } static struct buffer_head *minix_update_inode(struct inode *inode) { if (INODE_VERSION(inode) == MINIX_V1) return V1_minix_update_inode(inode); else return V2_minix_update_inode(inode); } static void minix_write_inode(struct inode * inode, int wait) { struct buffer_head *bh; lock_kernel(); bh = minix_update_inode(inode); unlock_kernel(); brelse(bh); } int minix_sync_inode(struct inode * inode) { int err = 0; struct buffer_head *bh; bh = minix_update_inode(inode); if (bh && buffer_dirty(bh)) { ll_rw_block(WRITE, 1, &bh); wait_on_buffer(bh); if (buffer_req(bh) && !buffer_uptodate(bh)) { printk ("IO error syncing minix inode [" "%s:%08lx]\n", kdevname(inode->i_dev), inode->i_ino); err = -1; } } else if (!bh) err = -1; brelse (bh); return err; } /* * The function that is called for file truncation. */ void minix_truncate(struct inode * inode) { if (INODE_VERSION(inode) == MINIX_V1) V1_minix_truncate(inode); else V2_minix_truncate(inode); } static DECLARE_FSTYPE_DEV(minix_fs_type,"minix",minix_read_super); static int __init init_minix_fs(void) { return register_filesystem(&minix_fs_type); } static void __exit exit_minix_fs(void) { unregister_filesystem(&minix_fs_type); } EXPORT_NO_SYMBOLS; module_init(init_minix_fs) module_exit(exit_minix_fs)