static int try_to_fill_dentry(struct dentry *dentry, struct super_block *sb, struct autofs_sb_info *sbi)
{
struct inode * inode;
struct autofs_dir_ent *ent;
int status = 0;
if (!(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name))) {
do {
if (status && dentry->d_inode) {
if (status != -ENOENT)
printk("autofs warning: lookup failure on positive dentry, status = %d, name = %s\n", status, dentry->d_name.name);
return 0; /* Try to get the kernel to invalidate this dentry */
}
/* Turn this into a real negative dentry? */
if (status == -ENOENT) {
dentry->d_time = jiffies + AUTOFS_NEGATIVE_TIMEOUT;
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
return 1;
} else if (status) {
/* Return a negative dentry, but leave it "pending" */
return 1;
}
status = autofs_wait(sbi, &dentry->d_name);
} while (!(ent = autofs_hash_lookup(&sbi->dirhash, &dentry->d_name)));
}
/* Abuse this field as a pointer to the directory entry, used to
find the expire list pointers */
dentry->d_time = (unsigned long) ent;
if (!dentry->d_inode) {
inode = autofs_iget(sb, ent->ino);
if (IS_ERR(inode)) {
/* Failed, but leave pending for next time */
return 1;
}
dentry->d_inode = inode;
}
/* If this is a directory that isn't a mount point, bitch at the
daemon and fix it in user space */
if (S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry)) {
return !autofs_wait(sbi, &dentry->d_name);
}
/* We don't update the usages for the autofs daemon itself, this
is necessary for recursive autofs mounts */
if (!autofs_oz_mode(sbi)) {
autofs_update_usage(&sbi->dirhash,ent);
}
dentry->d_flags &= ~DCACHE_AUTOFS_PENDING;
return 1;
}
/*
* NOTE!
*
* Normal filesystems would do a "d_delete()" to tell the VFS dcache
* that the file no longer exists. However, doing that means that the
* VFS layer can turn the dentry into a negative dentry, which we
* obviously do not want (we're dropping the entry not because it
* doesn't exist, but because it has timed out).
*
* Also see autofs_root_rmdir()..
*/
static int autofs_root_unlink(struct inode *dir, struct dentry *dentry)
{
struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
struct autofs_dirhash *dh = &sbi->dirhash;
struct autofs_dir_ent *ent;
unsigned int n;
/* This allows root to remove symlinks */
if ( !autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN) )
return -EACCES;
ent = autofs_hash_lookup(dh, &dentry->d_name);
if ( !ent )
return -ENOENT;
n = ent->ino - AUTOFS_FIRST_SYMLINK;
if ( n >= AUTOFS_MAX_SYMLINKS )
return -EISDIR; /* It's a directory, dummy */
if ( !test_bit(n,sbi->symlink_bitmap) )
return -EINVAL; /* Nonexistent symlink? Shouldn't happen */
dentry->d_time = (unsigned long)(struct autofs_dirhash *)NULL;
autofs_hash_delete(ent);
clear_bit(n,sbi->symlink_bitmap);
kfree(sbi->symlink[n].data);
d_drop(dentry);
return 0;
}
static int autofs_root_rmdir(struct inode *dir, struct dentry *dentry)
{
struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
struct autofs_dirhash *dh = &sbi->dirhash;
struct autofs_dir_ent *ent;
lock_kernel();
if (!autofs_oz_mode(sbi)) {
unlock_kernel();
return -EACCES;
}
ent = autofs_hash_lookup(dh, &dentry->d_name);
if (!ent) {
unlock_kernel();
return -ENOENT;
}
if ((unsigned int)ent->ino < AUTOFS_FIRST_DIR_INO) {
unlock_kernel();
return -ENOTDIR; /* Not a directory */
}
if (ent->dentry != dentry) {
printk("autofs_rmdir: odentry != dentry for entry %s\n", dentry->d_name.name);
}
dentry->d_time = (unsigned long)(struct autofs_dir_ent *)NULL;
autofs_hash_delete(ent);
drop_nlink(dir);
d_drop(dentry);
unlock_kernel();
return 0;
}
static int autofs_root_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
struct autofs_dirhash *dh = &sbi->dirhash;
struct autofs_dir_ent *ent;
struct inode *inode;
ino_t ino;
lock_kernel();
if (!autofs_oz_mode(sbi)) {
unlock_kernel();
return -EACCES;
}
ent = autofs_hash_lookup(dh, &dentry->d_name);
if (ent) {
unlock_kernel();
return -EEXIST;
}
if (sbi->next_dir_ino < AUTOFS_FIRST_DIR_INO) {
printk("autofs: Out of inode numbers -- what the heck did you do??\n");
unlock_kernel();
return -ENOSPC;
}
ino = sbi->next_dir_ino++;
ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL);
if (!ent) {
unlock_kernel();
return -ENOSPC;
}
ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL);
if (!ent->name) {
kfree(ent);
unlock_kernel();
return -ENOSPC;
}
ent->hash = dentry->d_name.hash;
memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len));
ent->ino = ino;
ent->dentry = dentry;
autofs_hash_insert(dh,ent);
inc_nlink(dir);
inode = autofs_iget(dir->i_sb, ino);
if (IS_ERR(inode)) {
drop_nlink(dir);
return PTR_ERR(inode);
}
d_instantiate(dentry, inode);
unlock_kernel();
return 0;
}
static int autofs_root_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
struct autofs_dirhash *dh = &sbi->dirhash;
struct autofs_dir_ent *ent;
unsigned int n;
int slsize;
struct autofs_symlink *sl;
DPRINTK(("autofs_root_symlink: %s <- ", symname));
autofs_say(dentry->d_name.name,dentry->d_name.len);
if ( !autofs_oz_mode(sbi) )
return -EACCES;
if ( autofs_hash_lookup(dh, &dentry->d_name) )
return -EEXIST;
n = find_first_zero_bit(sbi->symlink_bitmap,AUTOFS_MAX_SYMLINKS);
if ( n >= AUTOFS_MAX_SYMLINKS )
return -ENOSPC;
set_bit(n,sbi->symlink_bitmap);
sl = &sbi->symlink[n];
sl->len = strlen(symname);
sl->data = kmalloc(slsize = sl->len+1, GFP_KERNEL);
if ( !sl->data ) {
clear_bit(n,sbi->symlink_bitmap);
return -ENOSPC;
}
ent = kmalloc(sizeof(struct autofs_dir_ent), GFP_KERNEL);
if ( !ent ) {
kfree(sl->data);
clear_bit(n,sbi->symlink_bitmap);
return -ENOSPC;
}
ent->name = kmalloc(dentry->d_name.len+1, GFP_KERNEL);
if ( !ent->name ) {
kfree(sl->data);
kfree(ent);
clear_bit(n,sbi->symlink_bitmap);
return -ENOSPC;
}
memcpy(sl->data,symname,slsize);
sl->mtime = CURRENT_TIME;
ent->ino = AUTOFS_FIRST_SYMLINK + n;
ent->hash = dentry->d_name.hash;
memcpy(ent->name, dentry->d_name.name, 1+(ent->len = dentry->d_name.len));
ent->dentry = NULL; /* We don't keep the dentry for symlinks */
autofs_hash_insert(dh,ent);
d_instantiate(dentry, iget(dir->i_sb,ent->ino));
return 0;
}
