diff options
Diffstat (limited to 'fs/bfs/inode.c')
-rw-r--r-- | fs/bfs/inode.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c new file mode 100644 index 000000000..1926bec2c --- /dev/null +++ b/fs/bfs/inode.c @@ -0,0 +1,489 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * fs/bfs/inode.c + * BFS superblock and inode operations. + * Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com> + * From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds. + * Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005. + */ + +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/buffer_head.h> +#include <linux/vfs.h> +#include <linux/writeback.h> +#include <linux/uio.h> +#include <linux/uaccess.h> +#include "bfs.h" + +MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>"); +MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux"); +MODULE_LICENSE("GPL"); + +#undef DEBUG + +#ifdef DEBUG +#define dprintf(x...) printf(x) +#else +#define dprintf(x...) +#endif + +struct inode *bfs_iget(struct super_block *sb, unsigned long ino) +{ + struct bfs_inode *di; + struct inode *inode; + struct buffer_head *bh; + int block, off; + + inode = iget_locked(sb, ino); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) { + printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino); + goto error; + } + + block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; + bh = sb_bread(inode->i_sb, block); + if (!bh) { + printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, + ino); + goto error; + } + + off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; + di = (struct bfs_inode *)bh->b_data + off; + + inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode); + if (le32_to_cpu(di->i_vtype) == BFS_VDIR) { + inode->i_mode |= S_IFDIR; + inode->i_op = &bfs_dir_inops; + inode->i_fop = &bfs_dir_operations; + } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) { + inode->i_mode |= S_IFREG; + inode->i_op = &bfs_file_inops; + inode->i_fop = &bfs_file_operations; + inode->i_mapping->a_ops = &bfs_aops; + } + + BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock); + BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock); + BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); + i_uid_write(inode, le32_to_cpu(di->i_uid)); + i_gid_write(inode, le32_to_cpu(di->i_gid)); + set_nlink(inode, le32_to_cpu(di->i_nlink)); + inode->i_size = BFS_FILESIZE(di); + inode->i_blocks = BFS_FILEBLOCKS(di); + inode->i_atime.tv_sec = le32_to_cpu(di->i_atime); + inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime); + inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime); + inode->i_atime.tv_nsec = 0; + inode->i_mtime.tv_nsec = 0; + inode->i_ctime.tv_nsec = 0; + + brelse(bh); + unlock_new_inode(inode); + return inode; + +error: + iget_failed(inode); + return ERR_PTR(-EIO); +} + +static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p) +{ + if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) { + printf("Bad inode number %s:%08x\n", sb->s_id, ino); + return ERR_PTR(-EIO); + } + + ino -= BFS_ROOT_INO; + + *p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK); + if (!*p) { + printf("Unable to read inode %s:%08x\n", sb->s_id, ino); + return ERR_PTR(-EIO); + } + + return (struct bfs_inode *)(*p)->b_data + ino % BFS_INODES_PER_BLOCK; +} + +static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + struct bfs_sb_info *info = BFS_SB(inode->i_sb); + unsigned int ino = (u16)inode->i_ino; + unsigned long i_sblock; + struct bfs_inode *di; + struct buffer_head *bh; + int err = 0; + + dprintf("ino=%08x\n", ino); + + di = find_inode(inode->i_sb, ino, &bh); + if (IS_ERR(di)) + return PTR_ERR(di); + + mutex_lock(&info->bfs_lock); + + if (ino == BFS_ROOT_INO) + di->i_vtype = cpu_to_le32(BFS_VDIR); + else + di->i_vtype = cpu_to_le32(BFS_VREG); + + di->i_ino = cpu_to_le16(ino); + di->i_mode = cpu_to_le32(inode->i_mode); + di->i_uid = cpu_to_le32(i_uid_read(inode)); + di->i_gid = cpu_to_le32(i_gid_read(inode)); + di->i_nlink = cpu_to_le32(inode->i_nlink); + di->i_atime = cpu_to_le32(inode->i_atime.tv_sec); + di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); + di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); + i_sblock = BFS_I(inode)->i_sblock; + di->i_sblock = cpu_to_le32(i_sblock); + di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock); + di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1); + + mark_buffer_dirty(bh); + if (wbc->sync_mode == WB_SYNC_ALL) { + sync_dirty_buffer(bh); + if (buffer_req(bh) && !buffer_uptodate(bh)) + err = -EIO; + } + brelse(bh); + mutex_unlock(&info->bfs_lock); + return err; +} + +static void bfs_evict_inode(struct inode *inode) +{ + unsigned long ino = inode->i_ino; + struct bfs_inode *di; + struct buffer_head *bh; + struct super_block *s = inode->i_sb; + struct bfs_sb_info *info = BFS_SB(s); + struct bfs_inode_info *bi = BFS_I(inode); + + dprintf("ino=%08lx\n", ino); + + truncate_inode_pages_final(&inode->i_data); + invalidate_inode_buffers(inode); + clear_inode(inode); + + if (inode->i_nlink) + return; + + di = find_inode(s, inode->i_ino, &bh); + if (IS_ERR(di)) + return; + + mutex_lock(&info->bfs_lock); + /* clear on-disk inode */ + memset(di, 0, sizeof(struct bfs_inode)); + mark_buffer_dirty(bh); + brelse(bh); + + if (bi->i_dsk_ino) { + if (bi->i_sblock) + info->si_freeb += bi->i_eblock + 1 - bi->i_sblock; + info->si_freei++; + clear_bit(ino, info->si_imap); + bfs_dump_imap("evict_inode", s); + } + + /* + * If this was the last file, make the previous block + * "last block of the last file" even if there is no + * real file there, saves us 1 gap. + */ + if (info->si_lf_eblk == bi->i_eblock) + info->si_lf_eblk = bi->i_sblock - 1; + mutex_unlock(&info->bfs_lock); +} + +static void bfs_put_super(struct super_block *s) +{ + struct bfs_sb_info *info = BFS_SB(s); + + if (!info) + return; + + mutex_destroy(&info->bfs_lock); + kfree(info); + s->s_fs_info = NULL; +} + +static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *s = dentry->d_sb; + struct bfs_sb_info *info = BFS_SB(s); + u64 id = huge_encode_dev(s->s_bdev->bd_dev); + buf->f_type = BFS_MAGIC; + buf->f_bsize = s->s_blocksize; + buf->f_blocks = info->si_blocks; + buf->f_bfree = buf->f_bavail = info->si_freeb; + buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO; + buf->f_ffree = info->si_freei; + buf->f_fsid = u64_to_fsid(id); + buf->f_namelen = BFS_NAMELEN; + return 0; +} + +static struct kmem_cache *bfs_inode_cachep; + +static struct inode *bfs_alloc_inode(struct super_block *sb) +{ + struct bfs_inode_info *bi; + bi = alloc_inode_sb(sb, bfs_inode_cachep, GFP_KERNEL); + if (!bi) + return NULL; + return &bi->vfs_inode; +} + +static void bfs_free_inode(struct inode *inode) +{ + kmem_cache_free(bfs_inode_cachep, BFS_I(inode)); +} + +static void init_once(void *foo) +{ + struct bfs_inode_info *bi = foo; + + inode_init_once(&bi->vfs_inode); +} + +static int __init init_inodecache(void) +{ + bfs_inode_cachep = kmem_cache_create("bfs_inode_cache", + sizeof(struct bfs_inode_info), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD|SLAB_ACCOUNT), + init_once); + if (bfs_inode_cachep == NULL) + return -ENOMEM; + return 0; +} + +static void destroy_inodecache(void) +{ + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(bfs_inode_cachep); +} + +static const struct super_operations bfs_sops = { + .alloc_inode = bfs_alloc_inode, + .free_inode = bfs_free_inode, + .write_inode = bfs_write_inode, + .evict_inode = bfs_evict_inode, + .put_super = bfs_put_super, + .statfs = bfs_statfs, +}; + +void bfs_dump_imap(const char *prefix, struct super_block *s) +{ +#ifdef DEBUG + int i; + char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL); + + if (!tmpbuf) + return; + for (i = BFS_SB(s)->si_lasti; i >= 0; i--) { + if (i > PAGE_SIZE - 100) break; + if (test_bit(i, BFS_SB(s)->si_imap)) + strcat(tmpbuf, "1"); + else + strcat(tmpbuf, "0"); + } + printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf); + free_page((unsigned long)tmpbuf); +#endif +} + +static int bfs_fill_super(struct super_block *s, void *data, int silent) +{ + struct buffer_head *bh, *sbh; + struct bfs_super_block *bfs_sb; + struct inode *inode; + unsigned i; + struct bfs_sb_info *info; + int ret = -EINVAL; + unsigned long i_sblock, i_eblock, i_eoff, s_size; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + mutex_init(&info->bfs_lock); + s->s_fs_info = info; + s->s_time_min = 0; + s->s_time_max = U32_MAX; + + sb_set_blocksize(s, BFS_BSIZE); + + sbh = sb_bread(s, 0); + if (!sbh) + goto out; + bfs_sb = (struct bfs_super_block *)sbh->b_data; + if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { + if (!silent) + printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id, le32_to_cpu(bfs_sb->s_magic)); + goto out1; + } + if (BFS_UNCLEAN(bfs_sb, s) && !silent) + printf("%s is unclean, continuing\n", s->s_id); + + s->s_magic = BFS_MAGIC; + + if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) || + le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) { + printf("Superblock is corrupted on %s\n", s->s_id); + goto out1; + } + + info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1; + if (info->si_lasti == BFS_MAX_LASTI) + printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id); + else if (info->si_lasti > BFS_MAX_LASTI) { + printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id); + goto out1; + } + for (i = 0; i < BFS_ROOT_INO; i++) + set_bit(i, info->si_imap); + + s->s_op = &bfs_sops; + inode = bfs_iget(s, BFS_ROOT_INO); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto out1; + } + s->s_root = d_make_root(inode); + if (!s->s_root) { + ret = -ENOMEM; + goto out1; + } + + info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS; + info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS; + info->si_freei = 0; + info->si_lf_eblk = 0; + + /* can we read the last block? */ + bh = sb_bread(s, info->si_blocks - 1); + if (!bh) { + printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1); + ret = -EIO; + goto out2; + } + brelse(bh); + + bh = NULL; + for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) { + struct bfs_inode *di; + int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1; + int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK; + unsigned long eblock; + + if (!off) { + brelse(bh); + bh = sb_bread(s, block); + } + + if (!bh) + continue; + + di = (struct bfs_inode *)bh->b_data + off; + + /* test if filesystem is not corrupted */ + + i_eoff = le32_to_cpu(di->i_eoffset); + i_sblock = le32_to_cpu(di->i_sblock); + i_eblock = le32_to_cpu(di->i_eblock); + s_size = le32_to_cpu(bfs_sb->s_end); + + if (i_sblock > info->si_blocks || + i_eblock > info->si_blocks || + i_sblock > i_eblock || + (i_eoff != le32_to_cpu(-1) && i_eoff > s_size) || + i_sblock * BFS_BSIZE > i_eoff) { + + printf("Inode 0x%08x corrupted on %s\n", i, s->s_id); + + brelse(bh); + ret = -EIO; + goto out2; + } + + if (!di->i_ino) { + info->si_freei++; + continue; + } + set_bit(i, info->si_imap); + info->si_freeb -= BFS_FILEBLOCKS(di); + + eblock = le32_to_cpu(di->i_eblock); + if (eblock > info->si_lf_eblk) + info->si_lf_eblk = eblock; + } + brelse(bh); + brelse(sbh); + bfs_dump_imap("fill_super", s); + return 0; + +out2: + dput(s->s_root); + s->s_root = NULL; +out1: + brelse(sbh); +out: + mutex_destroy(&info->bfs_lock); + kfree(info); + s->s_fs_info = NULL; + return ret; +} + +static struct dentry *bfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super); +} + +static struct file_system_type bfs_fs_type = { + .owner = THIS_MODULE, + .name = "bfs", + .mount = bfs_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("bfs"); + +static int __init init_bfs_fs(void) +{ + int err = init_inodecache(); + if (err) + goto out1; + err = register_filesystem(&bfs_fs_type); + if (err) + goto out; + return 0; +out: + destroy_inodecache(); +out1: + return err; +} + +static void __exit exit_bfs_fs(void) +{ + unregister_filesystem(&bfs_fs_type); + destroy_inodecache(); +} + +module_init(init_bfs_fs) +module_exit(exit_bfs_fs) |