static struct buffer_head *minix_find_entry(register struct inode *dir,
char *name, size_t namelen,
struct minix_dir_entry **res_dir)
{
register struct buffer_head *bh;
struct minix_sb_info *info;
block_t block;
loff_t offset;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return NULL;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return NULL;
#else
namelen = info->s_namelen;
#endif
}
bh = NULL;
block = 0;
offset = 0L;
while (block * BLOCK_SIZE + offset < dir->i_size) {
if (!bh) {
bh = minix_bread(dir, block, 0);
if (!bh) {
block++;
continue;
}
map_buffer(bh);
}
*res_dir = (struct minix_dir_entry *) (bh->b_data + offset);
if (minix_match(namelen, name, bh, &offset, info)) {
return bh;
}
if (offset >= BLOCK_SIZE) {
unmap_brelse(bh);
bh = NULL;
offset = 0;
block++;
}
}
unmap_brelse(bh);
*res_dir = NULL;
return NULL;
}
int minix_rmdir(register struct inode *dir, char *name, size_t len)
{
int retval;
register struct inode *inode;
struct buffer_head *bh;
struct minix_dir_entry *de;
inode = NULL;
bh = minix_find_entry(dir, name, len, &de);
retval = -ENOENT;
if (!bh)
goto end_rmdir;
retval = -EPERM;
if (!(inode = iget(dir->i_sb, (ino_t) de->inode)))
goto end_rmdir;
if ((dir->i_mode & S_ISVTX) && !suser() &&
current->euid != inode->i_uid && current->euid != dir->i_uid)
goto end_rmdir;
if (inode->i_dev != dir->i_dev)
goto end_rmdir;
if (inode == dir) /* we may not delete ".", but "../dir" is ok */
goto end_rmdir;
if (!S_ISDIR(inode->i_mode)) {
retval = -ENOTDIR;
goto end_rmdir;
}
if (!empty_dir(inode)) {
retval = -ENOTEMPTY;
goto end_rmdir;
}
if (de->inode != inode->i_ino) {
retval = -ENOENT;
goto end_rmdir;
}
if (inode->i_count > 1) {
retval = -EBUSY;
goto end_rmdir;
}
if (inode->i_nlink != 2)
printk("empty directory has nlink!=2 (%u)\n", inode->i_nlink);
de->inode = 0;
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
mark_buffer_dirty(bh, 1);
inode->i_nlink = 0;
inode->i_dirt = 1;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
dir->i_nlink--;
dir->i_dirt = 1;
retval = 0;
end_rmdir:
iput(dir);
iput(inode);
unmap_brelse(bh);
return retval;
}
int minix_lookup(register struct inode *dir, char *name, size_t len,
register struct inode **result)
{
struct minix_dir_entry *de;
struct buffer_head *bh;
*result = NULL;
if (dir) {
if (S_ISDIR(dir->i_mode)) {
debug("minix_lookup: Entering minix_find_entry\n");
bh = minix_find_entry(dir, name, len, &de);
debug2("minix_lookup: minix_find_entry returned %x %d\n", bh,
bh->b_mapcount);
if (bh) {
unmap_brelse(bh);
*result = iget(dir->i_sb, (ino_t) de->inode);
iput(dir);
return (!*result) ? -EACCES : 0;
}
}
iput(dir);
}
return -ENOENT;
}
int minix_link(register struct inode *oldinode, register struct inode *dir,
char *name, size_t len)
{
int error;
struct buffer_head *bh;
struct minix_dir_entry *de;
error = -EPERM;
if (S_ISDIR(oldinode->i_mode))
goto mlink_err;
error = -EMLINK;
if (oldinode->i_nlink >= MINIX_LINK_MAX)
goto mlink_err;
error = -EEXIST;
bh = minix_find_entry(dir, name, len, &de);
if (bh) {
unmap_brelse(bh);
goto mlink_err;
}
error = minix_add_entry(dir, name, len, oldinode->i_ino);
if (!error) {
oldinode->i_nlink++;
oldinode->i_ctime = CURRENT_TIME;
oldinode->i_dirt = 1;
}
mlink_err:
iput(oldinode);
iput(dir);
return error;
}
int elksfs_lookup(register struct inode *dir, char *name, size_t len,
register struct inode **result)
{
struct buffer_head *bh;
struct elksfs_dir_entry *de;
ino_t ino;
*result = NULL;
if (!dir)
return -ENOENT;
if (!S_ISDIR(dir->i_mode)) {
iput(dir);
return -ENOENT;
}
debug("elksfs_lookup: Entering elksfs_find_entry\n");
bh = elksfs_find_entry(dir, name, len, &de);
debug2("elksfs_lookup: elksfs_find_entry returned %x %d\n", bh,
bh->b_mapcount);
if (!bh) {
iput(dir);
return -ENOENT;
}
map_buffer(bh);
ino = de->inode;
unmap_brelse(bh);
*result = iget(dir->i_sb, (ino_t) ino);
if (!*result) {
iput(dir);
return -EACCES;
}
iput(dir);
return 0;
}
static int minix_readlink(register struct inode *inode,
char *buffer, int buflen)
{
register struct buffer_head *bh;
size_t len;
if (!S_ISLNK(inode->i_mode)) {
iput(inode);
return -EINVAL;
}
bh = minix_bread(inode, 0, 0);
iput(inode);
if (!bh)
return 0;
map_buffer(bh);
if((len = strlen(bh->b_data) + 1) > buflen)
len = buflen;
if (len > 1023)
len = 1023;
memcpy_tofs(buffer, bh->b_data, len);
unmap_brelse(bh);
return len;
}
int minix_mknod(register struct inode *dir, char *name, size_t len,
int mode, int rdev)
{
int error;
register struct inode *inode;
struct buffer_head *bh;
struct minix_dir_entry *de;
/* if (!dir)
return -ENOENT;*/ /* Already checked by do_mknod() */
error = -EEXIST;
bh = minix_find_entry(dir, name, len, &de);
if (bh) {
unmap_brelse(bh);
goto mknod2;
}
error = -ENOSPC;
inode = minix_new_inode(dir, (__u16)mode);
if (!inode)
goto mknod2;
/*----------------------------------------------------------------------*/
if (S_ISBLK(mode) || S_ISCHR(mode))
inode->i_rdev = to_kdev_t(rdev);
/*----------------------------------------------------------------------*/
error = minix_add_entry(dir, name, len, inode->i_ino);
if (error) {
inode->i_nlink--;
inode->i_dirt = 1;
}
iput(inode);
mknod2:
iput(dir);
return error;
}
static int V1_trunc_indirect(register struct inode *inode,
int offset, unsigned short *p)
{
struct buffer_head *bh;
int i;
unsigned short tmp;
register struct buffer_head *ind_bh;
unsigned short *ind;
int retry = 0;
tmp = *p;
if (!tmp) return 0;
ind_bh = bread(inode->i_dev, (block_t) tmp);
if (tmp != *p) {
brelse(ind_bh);
return 1;
}
if (!ind_bh) {
*p = 0;
return 0;
}
map_buffer(ind_bh);
repeat:
for (i = INDIRECT_BLOCK(offset); i < 512; i++) {
if (i < 0) i = 0;
else if (i < INDIRECT_BLOCK(offset)) goto repeat;
ind = i + (unsigned short *) ind_bh->b_data;
tmp = *ind;
if (!tmp) continue;
bh = get_hash_table(inode->i_dev, (block_t) tmp);
if (i < INDIRECT_BLOCK(offset)) {
brelse(bh);
goto repeat;
}
if ((bh && bh->b_count != 1) || tmp != *ind) {
retry = 1;
brelse(bh);
continue;
}
*ind = 0;
mark_buffer_dirty(ind_bh, 1);
brelse(bh);
minix_free_block(inode->i_sb, tmp);
}
ind = (unsigned short *) ind_bh->b_data;
for (i = 0; i < 512; i++)
if (*(ind++)) break;
if (i >= 512) {
if (ind_bh->b_count != 1) retry = 1;
else {
tmp = *p;
*p = 0;
minix_free_block(inode->i_sb, tmp);
}
}
unmap_brelse(ind_bh);
return retry;
}
int minix_symlink(struct inode *dir, char *name, size_t len, char *symname)
{
int error;
register struct inode *inode;
register struct buffer_head *bh;
struct minix_dir_entry *de;
error = -EEXIST;
bh = minix_find_entry(dir, name, len, &de);
if (bh) {
unmap_brelse(bh);
goto symlink2;
}
error = -ENOSPC;
inode = minix_new_inode(dir, S_IFLNK);
if (!inode)
goto symlink2;
/*----------------------------------------------------------------------*/
bh = minix_bread(inode, 0, 1);
if (!bh)
goto symlink1;
map_buffer(bh);
if((error = strlen_fromfs(symname)) > 1023)
error = 1023;
memcpy_fromfs(bh->b_data, symname, error);
bh->b_data[error] = 0;
inode->i_size = (__u32) error;
mark_buffer_dirty(bh, 1);
unmap_brelse(bh);
/*----------------------------------------------------------------------*/
error = minix_add_entry(dir, name, len, inode->i_ino);
if (error) {
symlink1:
inode->i_nlink--;
inode->i_dirt = 1;
}
iput(inode);
symlink2:
iput(dir);
return error;
}
static int minix_follow_link(register struct inode *dir,
register struct inode *inode,
int flag, int mode, struct inode **res_inode)
{
/*
* FIXME: #1 Stack use is too high
* #2 Needs to be current->link_count as this is blocking
*/
int error;
struct buffer_head *bh;
static int link_count = 0;
__u16 ds, *pds;
*res_inode = NULL;
if (!dir) {
dir = current->fs.root;
dir->i_count++;
}
if (!inode) {
iput(dir);
return -ENOENT;
}
if (!S_ISLNK(inode->i_mode)) {
iput(dir);
*res_inode = inode;
return 0;
}
if ( /* current-> */ link_count > 5) {
iput(inode);
iput(dir);
return -ELOOP;
}
bh = minix_bread(inode, 0, 0);
iput(inode);
if (!bh) {
iput(dir);
return -EIO;
}
/* current-> */ link_count++;
map_buffer(bh);
pds = ¤t->t_regs.ds;
ds = *pds;
*pds = kernel_ds;
error = open_namei(bh->b_data, flag, mode, res_inode, dir);
*pds = ds;
/* current-> */ link_count--;
unmap_brelse(bh);
return error;
}
static int V1_trunc_dindirect(register struct inode *inode,
int offset, unsigned short *p)
{
int i;
unsigned short tmp;
register struct buffer_head *dind_bh;
unsigned short *dind;
int retry = 0;
if (!(tmp = *p))
return 0;
dind_bh = bread(inode->i_dev, (block_t) tmp);
if (tmp != *p) {
brelse(dind_bh);
return 1;
}
if (!dind_bh) {
*p = 0;
return 0;
}
map_buffer(dind_bh);
repeat:
for (i = DINDIRECT_BLOCK(offset); i < 512; i++) {
if (i < 0)
i = 0;
if (i < DINDIRECT_BLOCK(offset))
goto repeat;
dind = i + (unsigned short *) dind_bh->b_data;
retry |= V1_trunc_indirect(inode, offset + (i << 9), dind);
mark_buffer_dirty(dind_bh, 1);
}
dind = (unsigned short *) dind_bh->b_data;
for (i = 0; i < 512; i++)
if (*(dind++))
break;
if (i >= 512)
if (dind_bh->b_count != 1)
retry = 1;
else {
tmp = *p;
*p = 0;
inode->i_dirt = 1;
minix_free_block(inode->i_sb, tmp);
}
unmap_brelse(dind_bh);
return retry;
}
static int minix_add_entry(register struct inode *dir,
char *name,
size_t namelen,
ino_t ino)
{
unsigned short block;
loff_t offset;
register struct buffer_head *bh;
struct minix_dir_entry *de;
struct minix_sb_info *info;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0L;
while (1) {
if (!bh) {
bh = minix_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
map_buffer(bh);
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024L + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024L + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, info->s_namelen, name, de->name)) {
debug2("MINIXadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
size_t i;
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
memcpy_fromfs(de->name, name, namelen);
if((i = info->s_namelen - namelen) > 0)
memset(de->name + namelen, 0, i);
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
de->inode = ino;
mark_buffer_dirty(bh, 1);
unmap_brelse(bh);
break;
}
if (offset >= BLOCK_SIZE) {
unmap_brelse(bh);
bh = NULL;
offset = 0;
block++;
}
}
return 0;
}
int elksfs_mkdir(register struct inode *dir, char *name, size_t len, int mode)
{
struct buffer_head *bh, *dir_block;
register struct inode *inode;
struct elksfs_dir_entry *de;
struct elksfs_sb_info *info;
int error;
if (!dir || !dir->i_sb) {
iput(dir);
return -EINVAL;
}
info = &dir->i_sb->u.elksfs_sb;
bh = elksfs_find_entry(dir, name, len, &de);
if (bh) {
brelse(bh);
iput(dir);
return -EEXIST;
}
#if 0
/* Above checks if bh is returned and exits, so bh
* is NULL at this point
*/
map_buffer(bh);
#endif
if (dir->i_nlink >= ELKSFS_LINK_MAX) {
iput(dir);
return -EMLINK;
}
inode = elksfs_new_inode(dir);
if (!inode) {
iput(dir);
return -ENOSPC;
}
debug("m_mkdir: new_inode succeeded\n");
inode->i_op = &elksfs_dir_inode_operations;
inode->i_size = 2 * info->s_dirsize;
debug("m_mkdir: starting elksfs_bread\n");
dir_block = elksfs_bread(inode, 0, 1);
if (!dir_block) {
iput(dir);
inode->i_nlink--;
inode->i_dirt = 1;
iput(inode);
return -ENOSPC;
}
debug("m_mkdir: read succeeded\n");
map_buffer(dir_block);
de = (struct elksfs_dir_entry *) dir_block->b_data;
de->inode = inode->i_ino;
strcpy(de->name, ".");
de = (struct elksfs_dir_entry *) (dir_block->b_data + info->s_dirsize);
de->inode = dir->i_ino;
strcpy(de->name, "..");
inode->i_nlink = 2;
mark_buffer_dirty(dir_block, 1);
unmap_brelse(dir_block);
debug("m_mkdir: dir_block update succeeded\n");
inode->i_mode = S_IFDIR | (mode & 0777 & ~current->fs.umask);
if (dir->i_mode & S_ISGID)
inode->i_mode |= S_ISGID;
inode->i_dirt = 1;
error = elksfs_add_entry(dir, name, len, &bh, &de);
if (error) {
iput(dir);
inode->i_nlink = 0;
iput(inode);
return error;
}
map_buffer(bh);
de->inode = inode->i_ino;
mark_buffer_dirty(bh, 1);
dir->i_nlink++;
dir->i_dirt = 1;
iput(dir);
iput(inode);
unmap_brelse(bh);
debug("m_mkdir: done!\n");
return 0;
}
static int elksfs_add_entry(register struct inode *dir, char *name,
size_t namelen, struct buffer_head **res_buf,
struct elksfs_dir_entry **res_dir)
{
struct buffer_head *bh;
struct elksfs_dir_entry *de;
struct elksfs_sb_info *info;
unsigned long int i;
block_t block;
loff_t offset;
*res_buf = NULL;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.elksfs_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0;
while (1) {
if (!bh) {
bh = elksfs_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
}
map_buffer(bh);
de = (struct elksfs_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024 + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024 + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, (size_t) info->s_namelen, name,
de->name)) {
debug2("ELKSFSadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
for (i = 0; i < info->s_namelen; i++)
de->name[i] = (i < namelen)
? (char) get_fs_byte((unsigned char *) name + i)
: 0;
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
unmap_buffer(bh);
mark_buffer_dirty(bh, 1);
*res_dir = de;
break;
}
if (offset < 1024)
continue;
printk("elksfs_add_entry may need another unmap_buffer :)\n");
brelse(bh);
bh = NULL;
offset = 0;
block++;
}
*res_buf = bh;
return 0;
}
static int minix_add_entry(register struct inode *dir,
char *name,
size_t namelen,
struct buffer_head **res_buf,
struct minix_dir_entry **res_dir)
{
unsigned short block;
loff_t offset;
register struct buffer_head *bh;
struct minix_dir_entry *de;
struct minix_sb_info *info;
*res_buf = NULL;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0L;
while (1) {
if (!bh) {
bh = minix_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
map_buffer(bh);
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024L + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024L + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, info->s_namelen, name, de->name)) {
debug2("MINIXadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
size_t i;
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
for (i = 0; i < info->s_namelen; i++)
de->name[i] = (i < namelen) ? (char) get_fs_byte(name + i)
: '\0';
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
unmap_buffer(bh);
mark_buffer_dirty(bh, 1);
*res_dir = de;
break;
}
if (offset < 1024)
continue;
unmap_brelse(bh);
bh = NULL;
offset = 0;
block++;
}
*res_buf = bh;
return 0;
}
int minix_mkdir(register struct inode *dir, char *name, size_t len, int mode)
{
int error;
register struct inode *inode;
struct buffer_head *dir_block;
struct buffer_head *bh;
struct minix_dir_entry *de;
if (!dir || !dir->i_sb) {
iput(dir);
return -EINVAL;
}
bh = minix_find_entry(dir, name, len, &de);
if (bh) {
brelse(bh);
iput(dir);
return -EEXIST;
}
if (dir->i_nlink >= MINIX_LINK_MAX) {
iput(dir);
return -EMLINK;
}
inode = minix_new_inode(dir);
if (!inode) {
iput(dir);
return -ENOSPC;
}
debug("m_mkdir: new_inode succeeded\n");
inode->i_op = &minix_dir_inode_operations;
inode->i_size = 2 * dir->i_sb->u.minix_sb.s_dirsize;
debug("m_mkdir: starting minix_bread\n");
dir_block = minix_bread(inode, 0, 1);
if (!dir_block) {
iput(dir);
inode->i_nlink--;
inode->i_dirt = 1;
iput(inode);
return -ENOSPC;
}
debug("m_mkdir: read succeeded\n");
map_buffer(dir_block);
de = (struct minix_dir_entry *) dir_block->b_data;
de->inode = inode->i_ino;
strcpy(de->name, ".");
de =
(struct minix_dir_entry *) (dir_block->b_data +
dir->i_sb->u.minix_sb.s_dirsize);
de->inode = dir->i_ino;
strcpy(de->name, "..");
inode->i_nlink = 2;
mark_buffer_dirty(dir_block, 1);
unmap_brelse(dir_block);
debug("m_mkdir: dir_block update succeeded\n");
inode->i_mode = S_IFDIR | (mode & 0777 & ~current->fs.umask);
if (dir->i_mode & S_ISGID)
inode->i_mode |= S_ISGID;
inode->i_dirt = 1;
error = minix_add_entry(dir, name, len, &bh, &de);
if (error) {
iput(dir);
inode->i_nlink = 0;
iput(inode);
return error;
}
map_buffer(bh);
de->inode = inode->i_ino;
mark_buffer_dirty(bh, 1);
dir->i_nlink++;
dir->i_dirt = 1;
iput(dir);
iput(inode);
unmap_brelse(bh);
debug("m_mkdir: done!\n");
return 0;
}
static int blk_rw(struct inode *inode, register struct file *filp,
char *buf, size_t count, int wr)
{
register struct buffer_head *bh;
size_t chars, offset;
int written = 0;
while (count > 0) {
/*
* Offset to block/offset
*/
offset = ((size_t)filp->f_pos) & (BLOCK_SIZE - 1);
chars = BLOCK_SIZE - offset;
if (chars > count)
chars = count;
/*
* Read the block in - use getblk on a write
* of a whole block to avoid a read of the data.
*/
bh = getblk(inode->i_rdev, (block_t)(filp->f_pos >> BLOCK_SIZE_BITS));
if ((wr == BLOCK_READ) || (chars != BLOCK_SIZE)) {
if (!readbuf(bh)) {
if (!written) written = -EIO;
break;
}
}
map_buffer(bh);
if (wr == BLOCK_WRITE) {
/*
* Alter buffer, mark dirty
*/
memcpy_fromfs(bh->b_data + offset, buf, chars);
bh->b_uptodate = bh->b_dirty = 1;
/*
* Writing: queue physical I/O
*/
ll_rw_blk(WRITE, bh);
wait_on_buffer(bh);
if (!bh->b_uptodate) { /* Write error. */
unmap_brelse(bh);
if (!written) written = -EIO;
break;
}
} else {
/*
* Empty buffer data. Buffer unchanged
*/
memcpy_tofs(buf, bh->b_data + offset, chars);
}
/*
* Move on and release buffer
*/
unmap_brelse(bh);
buf += chars;
filp->f_pos += chars;
written += chars;
count -= chars;
}
return written;
}