WSL2-Linux-Kernel/fs/bfs/inode.c

421 строка
10 KiB
C

/*
* fs/bfs/inode.c
* BFS superblock and inode operations.
* Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
* From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>
#include <asm/uaccess.h>
#include "bfs.h"
MODULE_AUTHOR("Tigran A. Aivazian <tigran@veritas.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
void dump_imap(const char *prefix, struct super_block * s);
static void bfs_read_inode(struct inode * inode)
{
unsigned long ino = inode->i_ino;
struct bfs_inode * di;
struct buffer_head * bh;
int block, off;
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);
make_bad_inode(inode);
return;
}
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);
make_bad_inode(inode);
return;
}
off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
di = (struct bfs_inode *)bh->b_data + off;
inode->i_mode = 0x0000FFFF & di->i_mode;
if (di->i_vtype == BFS_VDIR) {
inode->i_mode |= S_IFDIR;
inode->i_op = &bfs_dir_inops;
inode->i_fop = &bfs_dir_operations;
} else if (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;
}
inode->i_uid = di->i_uid;
inode->i_gid = di->i_gid;
inode->i_nlink = di->i_nlink;
inode->i_size = BFS_FILESIZE(di);
inode->i_blocks = BFS_FILEBLOCKS(di);
inode->i_blksize = PAGE_SIZE;
inode->i_atime.tv_sec = di->i_atime;
inode->i_mtime.tv_sec = di->i_mtime;
inode->i_ctime.tv_sec = di->i_ctime;
inode->i_atime.tv_nsec = 0;
inode->i_mtime.tv_nsec = 0;
inode->i_ctime.tv_nsec = 0;
BFS_I(inode)->i_dsk_ino = di->i_ino; /* can be 0 so we store a copy */
BFS_I(inode)->i_sblock = di->i_sblock;
BFS_I(inode)->i_eblock = di->i_eblock;
brelse(bh);
}
static int bfs_write_inode(struct inode * inode, int unused)
{
unsigned long ino = inode->i_ino;
struct bfs_inode * di;
struct buffer_head * bh;
int block, off;
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);
return -EIO;
}
lock_kernel();
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);
unlock_kernel();
return -EIO;
}
off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
di = (struct bfs_inode *)bh->b_data + off;
if (inode->i_ino == BFS_ROOT_INO)
di->i_vtype = BFS_VDIR;
else
di->i_vtype = BFS_VREG;
di->i_ino = inode->i_ino;
di->i_mode = inode->i_mode;
di->i_uid = inode->i_uid;
di->i_gid = inode->i_gid;
di->i_nlink = inode->i_nlink;
di->i_atime = inode->i_atime.tv_sec;
di->i_mtime = inode->i_mtime.tv_sec;
di->i_ctime = inode->i_ctime.tv_sec;
di->i_sblock = BFS_I(inode)->i_sblock;
di->i_eblock = BFS_I(inode)->i_eblock;
di->i_eoffset = di->i_sblock * BFS_BSIZE + inode->i_size - 1;
mark_buffer_dirty(bh);
brelse(bh);
unlock_kernel();
return 0;
}
static void bfs_delete_inode(struct inode * inode)
{
unsigned long ino = inode->i_ino;
struct bfs_inode * di;
struct buffer_head * bh;
int block, off;
struct super_block * s = inode->i_sb;
struct bfs_sb_info * info = BFS_SB(s);
dprintf("ino=%08lx\n", inode->i_ino);
if (inode->i_ino < BFS_ROOT_INO || inode->i_ino > info->si_lasti) {
printf("invalid ino=%08lx\n", inode->i_ino);
return;
}
inode->i_size = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
lock_kernel();
mark_inode_dirty(inode);
block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
bh = sb_bread(s, block);
if (!bh) {
printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
unlock_kernel();
return;
}
off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
di = (struct bfs_inode *)bh->b_data + off;
if (di->i_ino) {
info->si_freeb += BFS_FILEBLOCKS(di);
info->si_freei++;
clear_bit(di->i_ino, info->si_imap);
dump_imap("delete_inode", s);
}
di->i_ino = 0;
di->i_sblock = 0;
mark_buffer_dirty(bh);
brelse(bh);
/* if this was the last file, make the previous
block "last files last block" even if there is no real file there,
saves us 1 gap */
if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
mark_buffer_dirty(info->si_sbh);
}
unlock_kernel();
clear_inode(inode);
}
static void bfs_put_super(struct super_block *s)
{
struct bfs_sb_info *info = BFS_SB(s);
brelse(info->si_sbh);
kfree(info->si_imap);
kfree(info);
s->s_fs_info = NULL;
}
static int bfs_statfs(struct super_block *s, struct kstatfs *buf)
{
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.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
buf->f_namelen = BFS_NAMELEN;
return 0;
}
static void bfs_write_super(struct super_block *s)
{
lock_kernel();
if (!(s->s_flags & MS_RDONLY))
mark_buffer_dirty(BFS_SB(s)->si_sbh);
s->s_dirt = 0;
unlock_kernel();
}
static kmem_cache_t * bfs_inode_cachep;
static struct inode *bfs_alloc_inode(struct super_block *sb)
{
struct bfs_inode_info *bi;
bi = kmem_cache_alloc(bfs_inode_cachep, SLAB_KERNEL);
if (!bi)
return NULL;
return &bi->vfs_inode;
}
static void bfs_destroy_inode(struct inode *inode)
{
kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
}
static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
{
struct bfs_inode_info *bi = foo;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR)
inode_init_once(&bi->vfs_inode);
}
static int init_inodecache(void)
{
bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
sizeof(struct bfs_inode_info),
0, SLAB_RECLAIM_ACCOUNT,
init_once, NULL);
if (bfs_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static void destroy_inodecache(void)
{
if (kmem_cache_destroy(bfs_inode_cachep))
printk(KERN_INFO "bfs_inode_cache: not all structures were freed\n");
}
static struct super_operations bfs_sops = {
.alloc_inode = bfs_alloc_inode,
.destroy_inode = bfs_destroy_inode,
.read_inode = bfs_read_inode,
.write_inode = bfs_write_inode,
.delete_inode = bfs_delete_inode,
.put_super = bfs_put_super,
.write_super = bfs_write_super,
.statfs = bfs_statfs,
};
void dump_imap(const char *prefix, struct super_block * s)
{
#if 0
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");
}
printk(KERN_ERR "BFS-fs: %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;
struct bfs_super_block * bfs_sb;
struct inode * inode;
int i, imap_len;
struct bfs_sb_info * info;
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
s->s_fs_info = info;
memset(info, 0, sizeof(*info));
sb_set_blocksize(s, BFS_BSIZE);
bh = sb_bread(s, 0);
if(!bh)
goto out;
bfs_sb = (struct bfs_super_block *)bh->b_data;
if (bfs_sb->s_magic != BFS_MAGIC) {
if (!silent)
printf("No BFS filesystem on %s (magic=%08x)\n",
s->s_id, bfs_sb->s_magic);
goto out;
}
if (BFS_UNCLEAN(bfs_sb, s) && !silent)
printf("%s is unclean, continuing\n", s->s_id);
s->s_magic = BFS_MAGIC;
info->si_bfs_sb = bfs_sb;
info->si_sbh = bh;
info->si_lasti = (bfs_sb->s_start - BFS_BSIZE)/sizeof(struct bfs_inode)
+ BFS_ROOT_INO - 1;
imap_len = info->si_lasti/8 + 1;
info->si_imap = kmalloc(imap_len, GFP_KERNEL);
if (!info->si_imap)
goto out;
memset(info->si_imap, 0, imap_len);
for (i=0; i<BFS_ROOT_INO; i++)
set_bit(i, info->si_imap);
s->s_op = &bfs_sops;
inode = iget(s, BFS_ROOT_INO);
if (!inode) {
kfree(info->si_imap);
goto out;
}
s->s_root = d_alloc_root(inode);
if (!s->s_root) {
iput(inode);
kfree(info->si_imap);
goto out;
}
info->si_blocks = (bfs_sb->s_end + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
info->si_freeb = (bfs_sb->s_end + 1 - bfs_sb->s_start)>>BFS_BSIZE_BITS;
info->si_freei = 0;
info->si_lf_eblk = 0;
info->si_lf_sblk = 0;
info->si_lf_ioff = 0;
for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
inode = iget(s,i);
if (BFS_I(inode)->i_dsk_ino == 0)
info->si_freei++;
else {
set_bit(i, info->si_imap);
info->si_freeb -= inode->i_blocks;
if (BFS_I(inode)->i_eblock > info->si_lf_eblk) {
info->si_lf_eblk = BFS_I(inode)->i_eblock;
info->si_lf_sblk = BFS_I(inode)->i_sblock;
info->si_lf_ioff = BFS_INO2OFF(i);
}
}
iput(inode);
}
if (!(s->s_flags & MS_RDONLY)) {
mark_buffer_dirty(bh);
s->s_dirt = 1;
}
dump_imap("read_super", s);
return 0;
out:
brelse(bh);
kfree(info);
s->s_fs_info = NULL;
return -EINVAL;
}
static struct super_block *bfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
}
static struct file_system_type bfs_fs_type = {
.owner = THIS_MODULE,
.name = "bfs",
.get_sb = bfs_get_sb,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
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)