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authorRalf Baechle <ralf@linux-mips.org>2000-01-29 01:41:54 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-01-29 01:41:54 +0000
commitf969d69ba9f952e5bdd38278e25e26a3e4a61a70 (patch)
treeb3530d803df59d726afaabebc6626987dee1ca05 /fs/bfs/dir.c
parenta10ce7ef2066b455d69187643ddf2073bfc4db24 (diff)
Merge with 2.3.27.
Diffstat (limited to 'fs/bfs/dir.c')
-rw-r--r--fs/bfs/dir.c382
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;
+}