diff options
Diffstat (limited to 'kernel/fs/minix/inode.c')
| -rw-r--r-- | kernel/fs/minix/inode.c | 690 |
1 files changed, 690 insertions, 0 deletions
diff --git a/kernel/fs/minix/inode.c b/kernel/fs/minix/inode.c new file mode 100644 index 000000000..1182d1e26 --- /dev/null +++ b/kernel/fs/minix/inode.c @@ -0,0 +1,690 @@ +/* + * linux/fs/minix/inode.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * Copyright (C) 1996 Gertjan van Wingerde + * Minix V2 fs support. + * + * Modified for 680x0 by Andreas Schwab + * Updated to filesystem version 3 by Daniel Aragones + */ + +#include <linux/module.h> +#include "minix.h" +#include <linux/buffer_head.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/highuid.h> +#include <linux/vfs.h> +#include <linux/writeback.h> + +static int minix_write_inode(struct inode *inode, + struct writeback_control *wbc); +static int minix_statfs(struct dentry *dentry, struct kstatfs *buf); +static int minix_remount (struct super_block * sb, int * flags, char * data); + +static void minix_evict_inode(struct inode *inode) +{ + truncate_inode_pages_final(&inode->i_data); + if (!inode->i_nlink) { + inode->i_size = 0; + minix_truncate(inode); + } + invalidate_inode_buffers(inode); + clear_inode(inode); + if (!inode->i_nlink) + minix_free_inode(inode); +} + +static void minix_put_super(struct super_block *sb) +{ + int i; + struct minix_sb_info *sbi = minix_sb(sb); + + if (!(sb->s_flags & MS_RDONLY)) { + if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ + sbi->s_ms->s_state = sbi->s_mount_state; + mark_buffer_dirty(sbi->s_sbh); + } + for (i = 0; i < sbi->s_imap_blocks; i++) + brelse(sbi->s_imap[i]); + for (i = 0; i < sbi->s_zmap_blocks; i++) + brelse(sbi->s_zmap[i]); + brelse (sbi->s_sbh); + kfree(sbi->s_imap); + sb->s_fs_info = NULL; + kfree(sbi); +} + +static struct kmem_cache * minix_inode_cachep; + +static struct inode *minix_alloc_inode(struct super_block *sb) +{ + struct minix_inode_info *ei; + ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL); + if (!ei) + return NULL; + return &ei->vfs_inode; +} + +static void minix_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + kmem_cache_free(minix_inode_cachep, minix_i(inode)); +} + +static void minix_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, minix_i_callback); +} + +static void init_once(void *foo) +{ + struct minix_inode_info *ei = (struct minix_inode_info *) foo; + + inode_init_once(&ei->vfs_inode); +} + +static int __init init_inodecache(void) +{ + minix_inode_cachep = kmem_cache_create("minix_inode_cache", + sizeof(struct minix_inode_info), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD), + init_once); + if (minix_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(minix_inode_cachep); +} + +static const struct super_operations minix_sops = { + .alloc_inode = minix_alloc_inode, + .destroy_inode = minix_destroy_inode, + .write_inode = minix_write_inode, + .evict_inode = minix_evict_inode, + .put_super = minix_put_super, + .statfs = minix_statfs, + .remount_fs = minix_remount, +}; + +static int minix_remount (struct super_block * sb, int * flags, char * data) +{ + struct minix_sb_info * sbi = minix_sb(sb); + struct minix_super_block * ms; + + sync_filesystem(sb); + ms = sbi->s_ms; + if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) + return 0; + if (*flags & MS_RDONLY) { + if (ms->s_state & MINIX_VALID_FS || + !(sbi->s_mount_state & MINIX_VALID_FS)) + return 0; + /* Mounting a rw partition read-only. */ + if (sbi->s_version != MINIX_V3) + ms->s_state = sbi->s_mount_state; + mark_buffer_dirty(sbi->s_sbh); + } else { + /* Mount a partition which is read-only, read-write. */ + if (sbi->s_version != MINIX_V3) { + sbi->s_mount_state = ms->s_state; + ms->s_state &= ~MINIX_VALID_FS; + } else { + sbi->s_mount_state = MINIX_VALID_FS; + } + mark_buffer_dirty(sbi->s_sbh); + + if (!(sbi->s_mount_state & MINIX_VALID_FS)) + printk("MINIX-fs warning: remounting unchecked fs, " + "running fsck is recommended\n"); + else if ((sbi->s_mount_state & MINIX_ERROR_FS)) + printk("MINIX-fs warning: remounting fs with errors, " + "running fsck is recommended\n"); + } + return 0; +} + +static int minix_fill_super(struct super_block *s, void *data, int silent) +{ + struct buffer_head *bh; + struct buffer_head **map; + struct minix_super_block *ms; + struct minix3_super_block *m3s = NULL; + unsigned long i, block; + struct inode *root_inode; + struct minix_sb_info *sbi; + int ret = -EINVAL; + + sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL); + if (!sbi) + return -ENOMEM; + s->s_fs_info = sbi; + + BUILD_BUG_ON(32 != sizeof (struct minix_inode)); + BUILD_BUG_ON(64 != sizeof(struct minix2_inode)); + + if (!sb_set_blocksize(s, BLOCK_SIZE)) + goto out_bad_hblock; + + if (!(bh = sb_bread(s, 1))) + goto out_bad_sb; + + ms = (struct minix_super_block *) bh->b_data; + sbi->s_ms = ms; + sbi->s_sbh = bh; + sbi->s_mount_state = ms->s_state; + sbi->s_ninodes = ms->s_ninodes; + sbi->s_nzones = ms->s_nzones; + sbi->s_imap_blocks = ms->s_imap_blocks; + sbi->s_zmap_blocks = ms->s_zmap_blocks; + sbi->s_firstdatazone = ms->s_firstdatazone; + sbi->s_log_zone_size = ms->s_log_zone_size; + sbi->s_max_size = ms->s_max_size; + s->s_magic = ms->s_magic; + if (s->s_magic == MINIX_SUPER_MAGIC) { + sbi->s_version = MINIX_V1; + sbi->s_dirsize = 16; + sbi->s_namelen = 14; + s->s_max_links = MINIX_LINK_MAX; + } else if (s->s_magic == MINIX_SUPER_MAGIC2) { + sbi->s_version = MINIX_V1; + sbi->s_dirsize = 32; + sbi->s_namelen = 30; + s->s_max_links = MINIX_LINK_MAX; + } else if (s->s_magic == MINIX2_SUPER_MAGIC) { + sbi->s_version = MINIX_V2; + sbi->s_nzones = ms->s_zones; + sbi->s_dirsize = 16; + sbi->s_namelen = 14; + s->s_max_links = MINIX2_LINK_MAX; + } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { + sbi->s_version = MINIX_V2; + sbi->s_nzones = ms->s_zones; + sbi->s_dirsize = 32; + sbi->s_namelen = 30; + s->s_max_links = MINIX2_LINK_MAX; + } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) { + m3s = (struct minix3_super_block *) bh->b_data; + s->s_magic = m3s->s_magic; + sbi->s_imap_blocks = m3s->s_imap_blocks; + sbi->s_zmap_blocks = m3s->s_zmap_blocks; + sbi->s_firstdatazone = m3s->s_firstdatazone; + sbi->s_log_zone_size = m3s->s_log_zone_size; + sbi->s_max_size = m3s->s_max_size; + sbi->s_ninodes = m3s->s_ninodes; + sbi->s_nzones = m3s->s_zones; + sbi->s_dirsize = 64; + sbi->s_namelen = 60; + sbi->s_version = MINIX_V3; + sbi->s_mount_state = MINIX_VALID_FS; + sb_set_blocksize(s, m3s->s_blocksize); + s->s_max_links = MINIX2_LINK_MAX; + } else + goto out_no_fs; + + /* + * Allocate the buffer map to keep the superblock small. + */ + if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0) + goto out_illegal_sb; + i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); + map = kzalloc(i, GFP_KERNEL); + if (!map) + goto out_no_map; + sbi->s_imap = &map[0]; + sbi->s_zmap = &map[sbi->s_imap_blocks]; + + block=2; + for (i=0 ; i < sbi->s_imap_blocks ; i++) { + if (!(sbi->s_imap[i]=sb_bread(s, block))) + goto out_no_bitmap; + block++; + } + for (i=0 ; i < sbi->s_zmap_blocks ; i++) { + if (!(sbi->s_zmap[i]=sb_bread(s, block))) + goto out_no_bitmap; + block++; + } + + minix_set_bit(0,sbi->s_imap[0]->b_data); + minix_set_bit(0,sbi->s_zmap[0]->b_data); + + /* Apparently minix can create filesystems that allocate more blocks for + * the bitmaps than needed. We simply ignore that, but verify it didn't + * create one with not enough blocks and bail out if so. + */ + block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize); + if (sbi->s_imap_blocks < block) { + printk("MINIX-fs: file system does not have enough " + "imap blocks allocated. Refusing to mount.\n"); + goto out_no_bitmap; + } + + block = minix_blocks_needed( + (sbi->s_nzones - sbi->s_firstdatazone + 1), + s->s_blocksize); + if (sbi->s_zmap_blocks < block) { + printk("MINIX-fs: file system does not have enough " + "zmap blocks allocated. Refusing to mount.\n"); + goto out_no_bitmap; + } + + /* set up enough so that it can read an inode */ + s->s_op = &minix_sops; + root_inode = minix_iget(s, MINIX_ROOT_INO); + if (IS_ERR(root_inode)) { + ret = PTR_ERR(root_inode); + goto out_no_root; + } + + ret = -ENOMEM; + s->s_root = d_make_root(root_inode); + if (!s->s_root) + goto out_no_root; + + if (!(s->s_flags & MS_RDONLY)) { + if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ + ms->s_state &= ~MINIX_VALID_FS; + mark_buffer_dirty(bh); + } + if (!(sbi->s_mount_state & MINIX_VALID_FS)) + printk("MINIX-fs: mounting unchecked file system, " + "running fsck is recommended\n"); + else if (sbi->s_mount_state & MINIX_ERROR_FS) + printk("MINIX-fs: mounting file system with errors, " + "running fsck is recommended\n"); + + return 0; + +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 < sbi->s_imap_blocks; i++) + brelse(sbi->s_imap[i]); + for (i = 0; i < sbi->s_zmap_blocks; i++) + brelse(sbi->s_zmap[i]); + kfree(sbi->s_imap); + goto out_release; + +out_no_map: + ret = -ENOMEM; + if (!silent) + printk("MINIX-fs: can't allocate map\n"); + goto out_release; + +out_illegal_sb: + if (!silent) + printk("MINIX-fs: bad superblock\n"); + goto out_release; + +out_no_fs: + if (!silent) + printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 " + "on device %s.\n", s->s_id); +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: + s->s_fs_info = NULL; + kfree(sbi); + return ret; +} + +static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + struct minix_sb_info *sbi = minix_sb(sb); + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + buf->f_type = sb->s_magic; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; + buf->f_bfree = minix_count_free_blocks(sb); + buf->f_bavail = buf->f_bfree; + buf->f_files = sbi->s_ninodes; + buf->f_ffree = minix_count_free_inodes(sb); + buf->f_namelen = sbi->s_namelen; + buf->f_fsid.val[0] = (u32)id; + buf->f_fsid.val[1] = (u32)(id >> 32); + + return 0; +} + +static int minix_get_block(struct inode *inode, sector_t 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); +} + +static int minix_writepage(struct page *page, struct writeback_control *wbc) +{ + return block_write_full_page(page, minix_get_block, wbc); +} + +static int minix_readpage(struct file *file, struct page *page) +{ + return block_read_full_page(page,minix_get_block); +} + +int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len) +{ + return __block_write_begin(page, pos, len, minix_get_block); +} + +static void minix_write_failed(struct address_space *mapping, loff_t to) +{ + struct inode *inode = mapping->host; + + if (to > inode->i_size) { + truncate_pagecache(inode, inode->i_size); + minix_truncate(inode); + } +} + +static int minix_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + int ret; + + ret = block_write_begin(mapping, pos, len, flags, pagep, + minix_get_block); + if (unlikely(ret)) + minix_write_failed(mapping, pos + len); + + return ret; +} + +static sector_t minix_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping,block,minix_get_block); +} + +static const struct address_space_operations minix_aops = { + .readpage = minix_readpage, + .writepage = minix_writepage, + .write_begin = minix_write_begin, + .write_end = generic_write_end, + .bmap = minix_bmap +}; + +static const struct inode_operations minix_symlink_inode_operations = { + .readlink = generic_readlink, + .follow_link = page_follow_link_light, + .put_link = page_put_link, + .getattr = minix_getattr, +}; + +void minix_set_inode(struct inode *inode, dev_t rdev) +{ + 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; + inode->i_mapping->a_ops = &minix_aops; + } else if (S_ISLNK(inode->i_mode)) { + inode->i_op = &minix_symlink_inode_operations; + inode->i_mapping->a_ops = &minix_aops; + } else + init_special_inode(inode, inode->i_mode, rdev); +} + +/* + * The minix V1 function to read an inode. + */ +static struct inode *V1_minix_iget(struct inode *inode) +{ + struct buffer_head * bh; + struct minix_inode * raw_inode; + struct minix_inode_info *minix_inode = minix_i(inode); + int i; + + raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); + if (!raw_inode) { + iget_failed(inode); + return ERR_PTR(-EIO); + } + inode->i_mode = raw_inode->i_mode; + i_uid_write(inode, raw_inode->i_uid); + i_gid_write(inode, raw_inode->i_gid); + set_nlink(inode, raw_inode->i_nlinks); + inode->i_size = raw_inode->i_size; + inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; + inode->i_mtime.tv_nsec = 0; + inode->i_atime.tv_nsec = 0; + inode->i_ctime.tv_nsec = 0; + inode->i_blocks = 0; + for (i = 0; i < 9; i++) + minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; + minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); + brelse(bh); + unlock_new_inode(inode); + return inode; +} + +/* + * The minix V2 function to read an inode. + */ +static struct inode *V2_minix_iget(struct inode *inode) +{ + struct buffer_head * bh; + struct minix2_inode * raw_inode; + struct minix_inode_info *minix_inode = minix_i(inode); + int i; + + raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); + if (!raw_inode) { + iget_failed(inode); + return ERR_PTR(-EIO); + } + inode->i_mode = raw_inode->i_mode; + i_uid_write(inode, raw_inode->i_uid); + i_gid_write(inode, raw_inode->i_gid); + set_nlink(inode, raw_inode->i_nlinks); + inode->i_size = raw_inode->i_size; + inode->i_mtime.tv_sec = raw_inode->i_mtime; + inode->i_atime.tv_sec = raw_inode->i_atime; + inode->i_ctime.tv_sec = raw_inode->i_ctime; + inode->i_mtime.tv_nsec = 0; + inode->i_atime.tv_nsec = 0; + inode->i_ctime.tv_nsec = 0; + inode->i_blocks = 0; + for (i = 0; i < 10; i++) + minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; + minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); + brelse(bh); + unlock_new_inode(inode); + return inode; +} + +/* + * The global function to read an inode. + */ +struct inode *minix_iget(struct super_block *sb, unsigned long ino) +{ + struct inode *inode; + + inode = iget_locked(sb, ino); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + if (INODE_VERSION(inode) == MINIX_V1) + return V1_minix_iget(inode); + else + return V2_minix_iget(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; + struct minix_inode_info *minix_inode = minix_i(inode); + int i; + + raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); + if (!raw_inode) + return NULL; + raw_inode->i_mode = inode->i_mode; + raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); + raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); + raw_inode->i_nlinks = inode->i_nlink; + raw_inode->i_size = inode->i_size; + raw_inode->i_time = inode->i_mtime.tv_sec; + if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) + raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); + else for (i = 0; i < 9; i++) + raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; + 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; + struct minix_inode_info *minix_inode = minix_i(inode); + int i; + + raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); + if (!raw_inode) + return NULL; + raw_inode->i_mode = inode->i_mode; + raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); + raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); + raw_inode->i_nlinks = inode->i_nlink; + raw_inode->i_size = inode->i_size; + raw_inode->i_mtime = inode->i_mtime.tv_sec; + raw_inode->i_atime = inode->i_atime.tv_sec; + raw_inode->i_ctime = inode->i_ctime.tv_sec; + if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) + raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); + else for (i = 0; i < 10; i++) + raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; + mark_buffer_dirty(bh); + return bh; +} + +static int minix_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + int err = 0; + struct buffer_head *bh; + + if (INODE_VERSION(inode) == MINIX_V1) + bh = V1_minix_update_inode(inode); + else + bh = V2_minix_update_inode(inode); + if (!bh) + return -EIO; + if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) { + sync_dirty_buffer(bh); + if (buffer_req(bh) && !buffer_uptodate(bh)) { + printk("IO error syncing minix inode [%s:%08lx]\n", + inode->i_sb->s_id, inode->i_ino); + err = -EIO; + } + } + brelse (bh); + return err; +} + +int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) +{ + struct super_block *sb = dentry->d_sb; + generic_fillattr(d_inode(dentry), stat); + if (INODE_VERSION(d_inode(dentry)) == MINIX_V1) + stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb); + else + stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb); + stat->blksize = sb->s_blocksize; + return 0; +} + +/* + * The function that is called for file truncation. + */ +void minix_truncate(struct inode * inode) +{ + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) + return; + if (INODE_VERSION(inode) == MINIX_V1) + V1_minix_truncate(inode); + else + V2_minix_truncate(inode); +} + +static struct dentry *minix_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super); +} + +static struct file_system_type minix_fs_type = { + .owner = THIS_MODULE, + .name = "minix", + .mount = minix_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("minix"); + +static int __init init_minix_fs(void) +{ + int err = init_inodecache(); + if (err) + goto out1; + err = register_filesystem(&minix_fs_type); + if (err) + goto out; + return 0; +out: + destroy_inodecache(); +out1: + return err; +} + +static void __exit exit_minix_fs(void) +{ + unregister_filesystem(&minix_fs_type); + destroy_inodecache(); +} + +module_init(init_minix_fs) +module_exit(exit_minix_fs) +MODULE_LICENSE("GPL"); + |