diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2000-01-29 01:41:54 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2000-01-29 01:41:54 +0000 |
commit | f969d69ba9f952e5bdd38278e25e26a3e4a61a70 (patch) | |
tree | b3530d803df59d726afaabebc6626987dee1ca05 /fs/bfs/dir.c | |
parent | a10ce7ef2066b455d69187643ddf2073bfc4db24 (diff) |
Merge with 2.3.27.
Diffstat (limited to 'fs/bfs/dir.c')
-rw-r--r-- | fs/bfs/dir.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c new file mode 100644 index 000000000..8aa200451 --- /dev/null +++ b/fs/bfs/dir.c @@ -0,0 +1,382 @@ +/* + * fs/bfs/dir.c + * BFS directory operations. + * Copyright (C) 1999 Tigran Aivazian <tigran@ocston.org> + */ + +#include <linux/sched.h> +#include <linux/string.h> +#include <linux/bfs_fs.h> +#include <linux/locks.h> + +#include "bfs_defs.h" + +#undef DEBUG + +#ifdef DEBUG +#define DBG(x...) printk(x) +#else +#define DBG(x...) +#endif + +static int bfs_add_entry(struct inode * dir, const char * name, int namelen, int ino); +static struct buffer_head * bfs_find_entry(struct inode * dir, + const char * name, int namelen, struct bfs_dirent ** res_dir); + +static ssize_t bfs_dir_read(struct file * f, char * buf, size_t count, loff_t *ppos) +{ + return -EISDIR; +} + +static int bfs_readdir(struct file * f, void * dirent, filldir_t filldir) +{ + struct inode * dir = f->f_dentry->d_inode; + struct buffer_head * bh; + struct bfs_dirent * de; + kdev_t dev = dir->i_dev; + unsigned int offset; + int block; + + if (!dir || !dir->i_sb || !S_ISDIR(dir->i_mode)) { + printk(KERN_ERR "BFS-fs: %s(): Bad inode or not a directory %s:%08lx\n", + __FUNCTION__, bdevname(dev), dir->i_ino); + return -EBADF; + } + + if (f->f_pos & (BFS_DIRENT_SIZE-1)) { + printk(KERN_ERR "BFS-fs: %s(): Bad f_pos=%08lx for %s:%08lx\n", + __FUNCTION__, (unsigned long)f->f_pos, bdevname(dev), dir->i_ino); + return -EBADF; + } + + while (f->f_pos < dir->i_size) { + offset = f->f_pos & (BFS_BSIZE-1); + block = dir->iu_sblock + (f->f_pos >> BFS_BSIZE_BITS); + bh = bread(dev, block, BFS_BSIZE); + if (!bh) { + f->f_pos += BFS_BSIZE - offset; + continue; + } + do { + de = (struct bfs_dirent *)(bh->b_data + offset); + if (de->ino) { + int size = strnlen(de->name, BFS_NAMELEN); + if (filldir(dirent, de->name, size, f->f_pos, de->ino) < 0) { + brelse(bh); + return 0; + } + } + offset += BFS_DIRENT_SIZE; + f->f_pos += BFS_DIRENT_SIZE; + } while (offset < BFS_BSIZE && f->f_pos < dir->i_size); + brelse(bh); + } + + UPDATE_ATIME(dir); + return 0; +} + +static struct file_operations bfs_dir_operations = { + llseek: NULL, + read: bfs_dir_read, + write: NULL, + readdir: bfs_readdir, + poll: NULL, + ioctl: NULL, + mmap: NULL, + open: NULL, + flush: NULL, + release: NULL, + fsync: file_fsync, + fasync: NULL, + check_media_change: NULL, + revalidate: NULL, +}; + +extern void dump_imap(const char *, struct super_block *); + +static int bfs_create(struct inode * dir, struct dentry * dentry, int mode) +{ + int err; + struct inode * inode; + struct super_block * s = dir->i_sb; + unsigned long ino; + + inode = get_empty_inode(); + if (!inode) + return -ENOSPC; + inode->i_sb = s; + ino = find_first_zero_bit(s->su_imap, s->su_lasti); + if (ino > s->su_lasti) { + iput(inode); + return -ENOSPC; + } + set_bit(ino, s->su_imap); + s->su_freei--; + inode->i_dev = s->s_dev; + inode->i_uid = current->fsuid; + inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current->fsgid; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + inode->i_blocks = inode->i_blksize = 0; + inode->i_op = &bfs_file_inops; + inode->i_mode = mode; + inode->i_ino = inode->iu_dsk_ino = ino; + inode->iu_sblock = inode->iu_eblock = 0; + insert_inode_hash(inode); + mark_inode_dirty(inode); + dump_imap("create",s); + + err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, inode->i_ino); + if (err) { + inode->i_nlink--; + mark_inode_dirty(inode); + iput(inode); + return err; + } + d_instantiate(dentry, inode); + return 0; +} + +static struct dentry * bfs_lookup(struct inode * dir, struct dentry * dentry) +{ + struct inode * inode = NULL; + struct buffer_head * bh; + struct bfs_dirent * de; + + if (dentry->d_name.len > BFS_NAMELEN) + return ERR_PTR(-ENAMETOOLONG); + + bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); + if (bh) { + unsigned long ino = le32_to_cpu(de->ino); + brelse(bh); + inode = iget(dir->i_sb, ino); + if (!inode) + return ERR_PTR(-EACCES); + } + d_add(dentry, inode); + return NULL; +} + +static int bfs_link(struct dentry * old, struct inode * dir, struct dentry * new) +{ + struct inode * inode = old->d_inode; + int err; + + if (S_ISDIR(inode->i_mode)) + return -EPERM; + + err = bfs_add_entry(dir, new->d_name.name, new->d_name.len, inode->i_ino); + if (err) + return err; + inode->i_nlink++; + inode->i_ctime = CURRENT_TIME; + mark_inode_dirty(inode); + inode->i_count++; + d_instantiate(new, inode); + return 0; +} + + +static int bfs_unlink(struct inode * dir, struct dentry * dentry) +{ + int error = -ENOENT; + struct inode * inode; + struct buffer_head * bh; + struct bfs_dirent * de; + + inode = dentry->d_inode; + bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); + if (!bh || de->ino != inode->i_ino) + goto out_brelse; + + if (!inode->i_nlink) { + printk(KERN_WARNING + "BFS-fs: %s(): unlinking non-existent file %s:%lu (nlink=%d)\n", + __FUNCTION__, bdevname(inode->i_dev), inode->i_ino, inode->i_nlink); + inode->i_nlink = 1; + } + de->ino = 0; + dir->i_version = ++event; + mark_buffer_dirty(bh, 1); + dir->i_ctime = dir->i_mtime = CURRENT_TIME; + mark_inode_dirty(dir); + inode->i_nlink--; + inode->i_ctime = dir->i_ctime; + mark_inode_dirty(inode); + d_delete(dentry); + error = 0; + +out_brelse: + brelse(bh); + return error; +} + +static int bfs_rename(struct inode * old_dir, struct dentry * old_dentry, + struct inode * new_dir, struct dentry * new_dentry) +{ + struct inode * old_inode, * new_inode; + struct buffer_head * old_bh, * new_bh; + struct bfs_dirent * old_de, * new_de; + int error = -ENOENT; + + old_bh = new_bh = NULL; + old_inode = old_dentry->d_inode; + if (S_ISDIR(old_inode->i_mode)) + return -EINVAL; + + old_bh = bfs_find_entry(old_dir, + old_dentry->d_name.name, + old_dentry->d_name.len, &old_de); + + if (!old_bh || old_de->ino != old_inode->i_ino) + goto end_rename; + + error = -EPERM; + new_inode = new_dentry->d_inode; + new_bh = bfs_find_entry(new_dir, + new_dentry->d_name.name, + new_dentry->d_name.len, &new_de); + + if (new_bh && !new_inode) { + brelse(new_bh); + new_bh = NULL; + } + if (!new_bh) { + error = bfs_add_entry(new_dir, + new_dentry->d_name.name, + new_dentry->d_name.len, old_inode->i_ino); + if (error) + goto end_rename; + } + old_de->ino = 0; + old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME; + old_dir->i_version = ++event; + mark_inode_dirty(old_dir); + if (new_inode) { + new_inode->i_nlink--; + new_inode->i_ctime = CURRENT_TIME; + mark_inode_dirty(new_inode); + } + mark_buffer_dirty(old_bh, 1); + error = 0; + +end_rename: + brelse(old_bh); + brelse(new_bh); + return error; +} + +struct inode_operations bfs_dir_inops = { + default_file_ops: &bfs_dir_operations, + create: bfs_create, + lookup: bfs_lookup, + link: bfs_link, + unlink: bfs_unlink, + symlink: NULL, + mkdir: NULL, + rmdir: NULL, + mknod: NULL, + rename: bfs_rename, + readlink: NULL, + follow_link: NULL, + get_block: NULL, + readpage: NULL, + writepage: NULL, + flushpage: NULL, + truncate: NULL, + permission: NULL, + smap: NULL, + revalidate: NULL +}; + +static int bfs_add_entry(struct inode * dir, const char * name, int namelen, int ino) +{ + struct buffer_head * bh; + struct bfs_dirent * de; + int block, sblock, eblock, off; + kdev_t dev; + int i; + + DBG(KERN_ERR "BFS-fs: %s(%s,%d)\n", __FUNCTION__, name, namelen); + + if (!namelen) + return -ENOENT; + if (namelen > BFS_NAMELEN) + return -ENAMETOOLONG; + + dev = dir->i_dev; + sblock = dir->iu_sblock; + eblock = dir->iu_eblock; + for (block=sblock; block<=eblock; block++) { + bh = bread(dev, block, BFS_BSIZE); + if(!bh) + return -ENOSPC; + for (off=0; off<BFS_BSIZE; off+=BFS_DIRENT_SIZE) { + de = (struct bfs_dirent *)(bh->b_data + off); + if (!de->ino) { + if ((block-sblock)*BFS_BSIZE + off >= dir->i_size) { + dir->i_size += BFS_DIRENT_SIZE; + dir->i_ctime = CURRENT_TIME; + } + dir->i_mtime = CURRENT_TIME; + mark_inode_dirty(dir); + dir->i_version = ++event; + de->ino = ino; + for (i=0; i<BFS_NAMELEN; i++) + de->name[i] = (i < namelen) ? name[i] : 0; + mark_buffer_dirty(bh, 1); + brelse(bh); + return 0; + } + } + brelse(bh); + } + return -ENOSPC; +} + +static inline int bfs_namecmp(int len, const char * name, const char * buffer) +{ + if (len < BFS_NAMELEN && buffer[len]) + return 0; + return !memcmp(name, buffer, len); +} + +static struct buffer_head * bfs_find_entry(struct inode * dir, + const char * name, int namelen, struct bfs_dirent ** res_dir) +{ + unsigned long block, offset; + struct buffer_head * bh; + struct bfs_sb_info * info; + struct bfs_dirent * de; + + *res_dir = NULL; + info = &dir->i_sb->u.bfs_sb; + if (namelen > BFS_NAMELEN) + return NULL; + bh = NULL; + block = offset = 0; + while (block * BFS_BSIZE + offset < dir->i_size) { + if (!bh) { + bh = bread(dir->i_dev, dir->iu_sblock + block, BFS_BSIZE); + if (!bh) { + block++; + continue; + } + } + de = (struct bfs_dirent *)(bh->b_data + offset); + offset += BFS_DIRENT_SIZE; + if (de->ino && bfs_namecmp(namelen, name, de->name)) { + *res_dir = de; + return bh; + } + if (offset < bh->b_size) + continue; + brelse(bh); + bh = NULL; + offset = 0; + block++; + } + brelse(bh); + return NULL; +} |