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/*
* 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 <linux/module.h>
#include <linux/fs.h>
#include <linux/minix_fs.h>
#include <linux/slab.h>
#include <linux/locks.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>
#include <linux/blkdev.h>
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;
}
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;
struct inode *root_inode;
unsigned int hblock;
struct minix_sb_info *sbi = &s->u.minix_sb;
/* 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_hardsect_size(dev);
if (hblock > BLOCK_SIZE)
goto out_bad_hblock;
set_blocksize(dev, BLOCK_SIZE);
s->s_blocksize = BLOCK_SIZE;
s->s_blocksize_bits = BLOCK_SIZE_BITS;
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;
sbi->s_link_max = MINIX_LINK_MAX;
} else if (s->s_magic == MINIX_SUPER_MAGIC2) {
sbi->s_version = MINIX_V1;
sbi->s_dirsize = 32;
sbi->s_namelen = 30;
sbi->s_link_max = 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;
sbi->s_link_max = 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;
sbi->s_link_max = MINIX2_LINK_MAX;
} else
goto out_no_fs;
/*
* Allocate the buffer map to keep the superblock small.
*/
i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
map = kmalloc(i, GFP_KERNEL);
if (!map)
goto out_no_map;
memset(map, 0, i);
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);
/* 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 || is_bad_inode(root_inode))
goto out_no_root;
s->s_root = d_alloc_root(root_inode);
if (!s->s_root)
goto out_iput;
if (!NO_TRUNCATE)
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 (!(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 s;
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 < 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:
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);
}
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);
}
static 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
};
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 = &page_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 void V1_minix_read_inode(struct inode * inode)
{
struct buffer_head * bh;
struct minix_inode * raw_inode;
int i;
raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
if (!raw_inode) {
make_bad_inode(inode);
return;
}
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 (i = 0; i < 9; i++)
inode->u.minix_i.u.i1_data[i] = raw_inode->i_zone[i];
minix_set_inode(inode, 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 i;
raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
if (!raw_inode) {
make_bad_inode(inode);
return;
}
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 (i = 0; i < 10; i++)
inode->u.minix_i.u.i2_data[i] = raw_inode->i_zone[i];
minix_set_inode(inode, 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 i;
raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
if (!raw_inode)
return 0;
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 (i = 0; i < 9; i++)
raw_inode->i_zone[i] = inode->u.minix_i.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;
int i;
raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
if (!raw_inode)
return 0;
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 (i = 0; i < 10; i++)
raw_inode->i_zone[i] = inode->u.minix_i.u.i2_data[i];
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)
MODULE_LICENSE("GPL");
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