/*
* See the comment in vnode.h for what is expected of this function.
*
* When this function returns, the inode refcount of the unlinked file
* should be decremented.
*
* You probably want to use s5_remove_dirent().
*/
static int
s5fs_unlink(vnode_t *dir, const char *name, size_t namelen)
{
KASSERT(dir->vn_ops->mkdir != NULL);
kmutex_lock(&dir->vn_mutex);
int ret = s5_remove_dirent(dir, name, namelen);
kmutex_unlock(&dir->vn_mutex);
return ret;
}
/*
* See the comment in vnode.h for what is expected of this function.
*
* When this function returns, the inode refcount on the parent should be
* decremented (since ".." in the removed directory no longer references
* it). Remember that the directory must be empty (except for "." and
* "..").
*
* You probably want to use s5_find_dirent() and s5_remove_dirent().
*/
static int
s5fs_rmdir(vnode_t *parent, const char *name, size_t namelen)
{
KASSERT(!(namelen == 1 && name[0] == '.'));
KASSERT(!(namelen == 2 && name[0] == '.' && name[1] == '.'));
KASSERT(parent->vn_ops->rmdir != NULL);
kmutex_lock(&parent->vn_mutex);
int ino = s5_find_dirent(parent, name, namelen);
/* we check in do_rmdir to make sure the directory exists */
KASSERT(ino != -ENOENT);
if (ino < 0){
dbg(DBG_S5FS, "error finding child dir to delete\n");
kmutex_unlock(&parent->vn_mutex);
return ino;
}
vnode_t *child = vget(VNODE_TO_S5FS(parent)->s5f_fs, ino);
kmutex_lock(&child->vn_mutex);
int dot_lookup_res = s5_find_dirent(child, ".", 1);
int dotdot_lookup_res = s5_find_dirent(child, "..", 2);
KASSERT(dot_lookup_res != -ENOENT && dotdot_lookup_res != -ENOENT);
if (dot_lookup_res < 0 || dotdot_lookup_res < 0){
dbg(DBG_S5FS, "error reading dirents of directory to delete\n");
kmutex_unlock(&child->vn_mutex);
kmutex_unlock(&parent->vn_mutex);
return (dot_lookup_res < 0) ? dot_lookup_res : dotdot_lookup_res;
}
KASSERT((unsigned) child->vn_len >= 2 * sizeof(s5_dirent_t));
if ((unsigned) child->vn_len > 2 * sizeof(s5_dirent_t)){
vput(child);
kmutex_unlock(&child->vn_mutex);
kmutex_unlock(&parent->vn_mutex);
return -ENOTEMPTY;
}
vput(child);
VNODE_TO_S5INODE(parent)->s5_linkcount--;
s5_dirty_inode(VNODE_TO_S5FS(parent), VNODE_TO_S5INODE(parent));
kmutex_unlock(&child->vn_mutex);
kmutex_unlock(&parent->vn_mutex);
return s5_remove_dirent(parent, name, namelen);
}
/*
* s5fs_unlink:
* s5fs_unlink removes the link to the vnode in dir specified by name
* param *dir: the parent's vnode
* param *name: name string
* param namelen: the length of the name
* return: 0 on success, and negative number on a variety of errors
*/
static int
s5fs_unlink(vnode_t *dir, const char *name, size_t namelen)
{
dbg(DBG_S5FS, "{\n");
KASSERT(dir != NULL);
KASSERT(name != NULL);
KASSERT(namelen <= S5_NAME_LEN-1);
kmutex_lock(&dir->vn_mutex);
int ret = 0;
if ((ret = s5_remove_dirent(dir, name, namelen)) < 0)
{
kmutex_unlock(&dir->vn_mutex);
return ret;
}
kmutex_unlock(&dir->vn_mutex);
dbg(DBG_S5FS, "}\n");
return ret;
}
/*
* s5fs_rmdir:
* s5fs_rmdir removes the directory called name from dir. the directory
* to be removed must be empty (except for . and .. of course).
* param *parent: the pointer to the parent dir of the name specified
* param *name: name string
* param namelen: the length of the name string
* return: 0 on success; negative numbers on a variety of errors
*/
static int
s5fs_rmdir(vnode_t *parent, const char *name, size_t namelen)
{
dbg(DBG_S5FS, "{\n");
KASSERT(parent != NULL);
KASSERT(name != NULL);
KASSERT(namelen <= NAME_LEN - 1);
KASSERT((uint32_t)parent->vn_len == VNODE_TO_S5INODE(parent)->s5_size);
kmutex_lock(&parent->vn_mutex);
int inode_number = 0;
if ((inode_number = s5_find_dirent(parent, name, namelen)) < 0)
{
kmutex_unlock(&parent->vn_mutex);
/* Need vput? */
return inode_number;
}
/* May block here */
vnode_t* vn = vget(parent->vn_fs, inode_number);
KASSERT(vn != NULL);
if (!S_ISDIR(vn->vn_mode))
{
/* May block here */
vput(vn);
kmutex_unlock(&parent->vn_mutex);
return -ENOTDIR;
}
/* Check empty */
if (VNODE_TO_S5INODE(vn)->s5_size > sizeof(dirent_t)*2)
{
vput(vn);
kmutex_unlock(&parent->vn_mutex);
return -ENOTEMPTY;
}
int ret;
if ((ret = s5_remove_dirent(parent, name, namelen)) < 0)
{
/* May block here */
vput(vn);
kmutex_unlock(&parent->vn_mutex);
return ret;
}
/* Decrease the linkcount because .. is removed */
s5_inode_t* parent_inode = VNODE_TO_S5INODE(parent);
parent_inode->s5_linkcount--;
s5_dirty_inode(VNODE_TO_S5FS(parent), parent_inode);
/* May block here */
vput(vn);
kmutex_unlock(&parent->vn_mutex);
dbg(DBG_S5FS, "}\n");
return ret;
}
