Esempio n. 1
0
static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
		      struct inode *new_dir, struct dentry *new_dentry)
{
	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
	struct key *key;
	int ret;

	vnode = AFS_FS_I(old_dentry->d_inode);
	orig_dvnode = AFS_FS_I(old_dir);
	new_dvnode = AFS_FS_I(new_dir);

	_enter("{%x:%u},{%x:%u},{%x:%u},{%s}",
	       orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
	       vnode->fid.vid, vnode->fid.vnode,
	       new_dvnode->fid.vid, new_dvnode->fid.vnode,
	       new_dentry->d_name.name);

	ret = -ENAMETOOLONG;
	if (new_dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	key = afs_request_key(orig_dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_rename(orig_dvnode, new_dvnode, key,
			       old_dentry->d_name.name,
			       new_dentry->d_name.name);
	if (ret < 0)
		goto rename_error;
	key_put(key);
	_leave(" = 0");
	return 0;

rename_error:
	key_put(key);
error:
	d_drop(new_dentry);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 2
0
File: dir.c Progetto: mdamt/linux
/*
 * rename a file in an AFS filesystem and/or move it between directories
 */
static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
		      struct inode *new_dir, struct dentry *new_dentry,
		      unsigned int flags)
{
	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
	struct key *key;
	int ret;

	if (flags)
		return -EINVAL;

	vnode = AFS_FS_I(d_inode(old_dentry));
	orig_dvnode = AFS_FS_I(old_dir);
	new_dvnode = AFS_FS_I(new_dir);

	_enter("{%x:%u},{%x:%u},{%x:%u},{%pd}",
	       orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
	       vnode->fid.vid, vnode->fid.vnode,
	       new_dvnode->fid.vid, new_dvnode->fid.vnode,
	       new_dentry);

	key = afs_request_key(orig_dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_rename(orig_dvnode, new_dvnode, key,
			       old_dentry->d_name.name,
			       new_dentry->d_name.name);
	if (ret < 0)
		goto rename_error;
	key_put(key);
	_leave(" = 0");
	return 0;

rename_error:
	key_put(key);
error:
	d_drop(new_dentry);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 3
0
/*
 * create a hard link between files in an AFS filesystem
 */
static int afs_link(struct dentry *from, struct inode *dir,
		    struct dentry *dentry)
{
	struct afs_vnode *dvnode, *vnode;
	struct key *key;
	int ret;

	vnode = AFS_FS_I(from->d_inode);
	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%x:%u},{%s}",
	       vnode->fid.vid, vnode->fid.vnode,
	       dvnode->fid.vid, dvnode->fid.vnode,
	       dentry->d_name.name);

	ret = -ENAMETOOLONG;
	if (dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_link(dvnode, vnode, key, dentry->d_name.name);
	if (ret < 0)
		goto link_error;

	ihold(&vnode->vfs_inode);
	d_instantiate(dentry, &vnode->vfs_inode);
	key_put(key);
	_leave(" = 0");
	return 0;

link_error:
	key_put(key);
error:
	d_drop(dentry);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 4
0
/*
 * remove a directory from an AFS filesystem
 */
static int afs_rmdir(struct inode *dir, struct dentry *dentry)
{
	struct afs_vnode *dvnode, *vnode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%s}",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name);

	ret = -ENAMETOOLONG;
	if (dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, true);
	if (ret < 0)
		goto rmdir_error;

	if (dentry->d_inode) {
		vnode = AFS_FS_I(dentry->d_inode);
		clear_nlink(&vnode->vfs_inode);
		set_bit(AFS_VNODE_DELETED, &vnode->flags);
		afs_discard_callback_on_delete(vnode);
	}

	key_put(key);
	_leave(" = 0");
	return 0;

rmdir_error:
	key_put(key);
error:
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 5
0
static int afs_readpage(struct file *file, struct page *page)
{
	struct key *key;
	int ret;

	if (file) {
		key = file->private_data;
		ASSERT(key != NULL);
		ret = afs_page_filler(key, page);
	} else {
		struct inode *inode = page->mapping->host;
		key = afs_request_key(AFS_FS_S(inode->i_sb)->volume->cell);
		if (IS_ERR(key)) {
			ret = PTR_ERR(key);
		} else {
			ret = afs_page_filler(key, page);
			key_put(key);
		}
	}
	return ret;
}
Esempio n. 6
0
File: inode.c Progetto: 020gzh/linux
/*
 * set the attributes of an inode
 */
int afs_setattr(struct dentry *dentry, struct iattr *attr)
{
	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
	struct key *key;
	int ret;

	_enter("{%x:%u},{n=%pd},%x",
	       vnode->fid.vid, vnode->fid.vnode, dentry,
	       attr->ia_valid);

	if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
				ATTR_MTIME))) {
		_leave(" = 0 [unsupported]");
		return 0;
	}

	/* flush any dirty data outstanding on a regular file */
	if (S_ISREG(vnode->vfs_inode.i_mode)) {
		filemap_write_and_wait(vnode->vfs_inode.i_mapping);
		afs_writeback_all(vnode);
	}

	if (attr->ia_valid & ATTR_FILE) {
		key = attr->ia_file->private_data;
	} else {
		key = afs_request_key(vnode->volume->cell);
		if (IS_ERR(key)) {
			ret = PTR_ERR(key);
			goto error;
		}
	}

	ret = afs_vnode_setattr(vnode, key, attr);
	if (!(attr->ia_valid & ATTR_FILE))
		key_put(key);

error:
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 7
0
/*
 * Validate the options, get the cell key and look up the volume.
 */
static int afs_validate_fc(struct fs_context *fc)
{
	struct afs_fs_context *ctx = fc->fs_private;
	struct afs_volume *volume;
	struct key *key;

	if (!ctx->dyn_root) {
		if (ctx->no_cell) {
			pr_warn("kAFS: Can only specify source 'none' with -o dyn\n");
			return -EINVAL;
		}

		if (!ctx->cell) {
			pr_warn("kAFS: No cell specified\n");
			return -EDESTADDRREQ;
		}

		/* We try to do the mount securely. */
		key = afs_request_key(ctx->cell);
		if (IS_ERR(key))
			return PTR_ERR(key);

		ctx->key = key;

		if (ctx->volume) {
			afs_put_volume(ctx->cell, ctx->volume);
			ctx->volume = NULL;
		}

		volume = afs_create_volume(ctx);
		if (IS_ERR(volume))
			return PTR_ERR(volume);

		ctx->volume = volume;
	}

	return 0;
}
Esempio n. 8
0
/*
 * open an AFS file or directory and attach a key to it
 */
int afs_open(struct inode *inode, struct file *file)
{
	struct afs_vnode *vnode = AFS_FS_I(inode);
	struct key *key;
	int ret;

	_enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		return PTR_ERR(key);
	}

	ret = afs_validate(vnode, key);
	if (ret < 0) {
		_leave(" = %d [val]", ret);
		return ret;
	}

	file->private_data = key;
	_leave(" = 0");
	return 0;
}
Esempio n. 9
0
/*
 * create a regular file on an AFS filesystem
 */
static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
		      bool excl)
{
	struct afs_file_status status;
	struct afs_callback cb;
	struct afs_server *server;
	struct afs_vnode *dvnode, *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%pd},%ho,",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	mode |= S_IFREG;
	ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
			       mode, &fid, &status, &cb, &server);
	if (ret < 0)
		goto create_error;

	inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
	if (IS_ERR(inode)) {
		/* ENOMEM at a really inconvenient time - just abandon the new
		 * directory on the server */
		ret = PTR_ERR(inode);
		goto iget_error;
	}

	/* apply the status report we've got for the new vnode */
	vnode = AFS_FS_I(inode);
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);
	afs_vnode_finalise_status_update(vnode, server);
	afs_put_server(server);

	d_instantiate(dentry, inode);
	if (d_unhashed(dentry)) {
		_debug("not hashed");
		d_rehash(dentry);
	}
	key_put(key);
	_leave(" = 0");
	return 0;

iget_error:
	afs_put_server(server);
create_error:
	key_put(key);
error:
	d_drop(dentry);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 10
0
/*
 * remove a file from an AFS filesystem
 */
static int afs_unlink(struct inode *dir, struct dentry *dentry)
{
	struct afs_vnode *dvnode, *vnode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%pd}",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry);

	ret = -ENAMETOOLONG;
	if (dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	if (d_really_is_positive(dentry)) {
		vnode = AFS_FS_I(d_inode(dentry));

		/* make sure we have a callback promise on the victim */
		ret = afs_validate(vnode, key);
		if (ret < 0)
			goto error;
	}

	ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, false);
	if (ret < 0)
		goto remove_error;

	if (d_really_is_positive(dentry)) {
		/* if the file wasn't deleted due to excess hard links, the
		 * fileserver will break the callback promise on the file - if
		 * it had one - before it returns to us, and if it was deleted,
		 * it won't
		 *
		 * however, if we didn't have a callback promise outstanding,
		 * or it was outstanding on a different server, then it won't
		 * break it either...
		 */
		vnode = AFS_FS_I(d_inode(dentry));
		if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
			_debug("AFS_VNODE_DELETED");
		if (test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags))
			_debug("AFS_VNODE_CB_BROKEN");
		set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
		ret = afs_validate(vnode, key);
		_debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret);
	}

	key_put(key);
	_leave(" = 0");
	return 0;

remove_error:
	key_put(key);
error:
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 11
0
/*
 * do a lookup in a directory
 * - just returns the FID the dentry name maps to if found
 */
static int afs_do_lookup(struct inode *dir, struct dentry *dentry,
			 struct afs_fid *fid, struct key *key)
{
	struct afs_super_info *as = dir->i_sb->s_fs_info;
	struct afs_lookup_cookie cookie = {
		.ctx.actor = afs_lookup_filldir,
		.name = dentry->d_name,
		.fid.vid = as->volume->vid
	};
	int ret;

	_enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);

	/* search the directory */
	ret = afs_dir_iterate(dir, &cookie.ctx, key);
	if (ret < 0) {
		_leave(" = %d [iter]", ret);
		return ret;
	}

	ret = -ENOENT;
	if (!cookie.found) {
		_leave(" = -ENOENT [not found]");
		return -ENOENT;
	}

	*fid = cookie.fid;
	_leave(" = 0 { vn=%u u=%u }", fid->vnode, fid->unique);
	return 0;
}

/*
 * Try to auto mount the mountpoint with pseudo directory, if the autocell
 * operation is setted.
 */
static struct inode *afs_try_auto_mntpt(
	int ret, struct dentry *dentry, struct inode *dir, struct key *key,
	struct afs_fid *fid)
{
	const char *devname = dentry->d_name.name;
	struct afs_vnode *vnode = AFS_FS_I(dir);
	struct inode *inode;

	_enter("%d, %p{%pd}, {%x:%u}, %p",
	       ret, dentry, dentry, vnode->fid.vid, vnode->fid.vnode, key);

	if (ret != -ENOENT ||
	    !test_bit(AFS_VNODE_AUTOCELL, &vnode->flags))
		goto out;

	inode = afs_iget_autocell(dir, devname, strlen(devname), key);
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto out;
	}

	*fid = AFS_FS_I(inode)->fid;
	_leave("= %p", inode);
	return inode;

out:
	_leave("= %d", ret);
	return ERR_PTR(ret);
}

/*
 * look up an entry in a directory
 */
static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
				 unsigned int flags)
{
	struct afs_vnode *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	vnode = AFS_FS_I(dir);

	_enter("{%x:%u},%p{%pd},",
	       vnode->fid.vid, vnode->fid.vnode, dentry, dentry);

	ASSERTCMP(d_inode(dentry), ==, NULL);

	if (dentry->d_name.len >= AFSNAMEMAX) {
		_leave(" = -ENAMETOOLONG");
		return ERR_PTR(-ENAMETOOLONG);
	}

	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
		_leave(" = -ESTALE");
		return ERR_PTR(-ESTALE);
	}

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		return ERR_CAST(key);
	}

	ret = afs_validate(vnode, key);
	if (ret < 0) {
		key_put(key);
		_leave(" = %d [val]", ret);
		return ERR_PTR(ret);
	}

	ret = afs_do_lookup(dir, dentry, &fid, key);
	if (ret < 0) {
		inode = afs_try_auto_mntpt(ret, dentry, dir, key, &fid);
		if (!IS_ERR(inode)) {
			key_put(key);
			goto success;
		}

		ret = PTR_ERR(inode);
		key_put(key);
		if (ret == -ENOENT) {
			d_add(dentry, NULL);
			_leave(" = NULL [negative]");
			return NULL;
		}
		_leave(" = %d [do]", ret);
		return ERR_PTR(ret);
	}
	dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version;

	/* instantiate the dentry */
	inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL);
	key_put(key);
	if (IS_ERR(inode)) {
		_leave(" = %ld", PTR_ERR(inode));
		return ERR_CAST(inode);
	}

success:
	d_add(dentry, inode);
	_leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%u }",
	       fid.vnode,
	       fid.unique,
	       d_inode(dentry)->i_ino,
	       d_inode(dentry)->i_generation);

	return NULL;
}

/*
 * check that a dentry lookup hit has found a valid entry
 * - NOTE! the hit can be a negative hit too, so we can't assume we have an
 *   inode
 */
static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
{
	struct afs_vnode *vnode, *dir;
	struct afs_fid uninitialized_var(fid);
	struct dentry *parent;
	struct key *key;
	void *dir_version;
	int ret;

	if (flags & LOOKUP_RCU)
		return -ECHILD;

	vnode = AFS_FS_I(d_inode(dentry));

	if (d_really_is_positive(dentry))
		_enter("{v={%x:%u} n=%pd fl=%lx},",
		       vnode->fid.vid, vnode->fid.vnode, dentry,
		       vnode->flags);
	else
		_enter("{neg n=%pd}", dentry);

	key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
	if (IS_ERR(key))
		key = NULL;

	/* lock down the parent dentry so we can peer at it */
	parent = dget_parent(dentry);
	dir = AFS_FS_I(d_inode(parent));

	/* validate the parent directory */
	if (test_bit(AFS_VNODE_MODIFIED, &dir->flags))
		afs_validate(dir, key);

	if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
		_debug("%pd: parent dir deleted", dentry);
		goto out_bad;
	}

	dir_version = (void *) (unsigned long) dir->status.data_version;
	if (dentry->d_fsdata == dir_version)
		goto out_valid; /* the dir contents are unchanged */

	_debug("dir modified");

	/* search the directory for this vnode */
	ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key);
	switch (ret) {
	case 0:
		/* the filename maps to something */
		if (d_really_is_negative(dentry))
			goto out_bad;
		if (is_bad_inode(d_inode(dentry))) {
			printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
			       dentry);
			goto out_bad;
		}

		/* if the vnode ID has changed, then the dirent points to a
		 * different file */
		if (fid.vnode != vnode->fid.vnode) {
			_debug("%pd: dirent changed [%u != %u]",
			       dentry, fid.vnode,
			       vnode->fid.vnode);
			goto not_found;
		}

		/* if the vnode ID uniqifier has changed, then the file has
		 * been deleted and replaced, and the original vnode ID has
		 * been reused */
		if (fid.unique != vnode->fid.unique) {
			_debug("%pd: file deleted (uq %u -> %u I:%u)",
			       dentry, fid.unique,
			       vnode->fid.unique,
			       d_inode(dentry)->i_generation);
			spin_lock(&vnode->lock);
			set_bit(AFS_VNODE_DELETED, &vnode->flags);
			spin_unlock(&vnode->lock);
			goto not_found;
		}
		goto out_valid;

	case -ENOENT:
		/* the filename is unknown */
		_debug("%pd: dirent not found", dentry);
		if (d_really_is_positive(dentry))
			goto not_found;
		goto out_valid;

	default:
		_debug("failed to iterate dir %pd: %d",
		       parent, ret);
		goto out_bad;
	}

out_valid:
	dentry->d_fsdata = dir_version;
	dput(parent);
	key_put(key);
	_leave(" = 1 [valid]");
	return 1;

	/* the dirent, if it exists, now points to a different vnode */
not_found:
	spin_lock(&dentry->d_lock);
	dentry->d_flags |= DCACHE_NFSFS_RENAMED;
	spin_unlock(&dentry->d_lock);

out_bad:
	_debug("dropping dentry %pd2", dentry);
	dput(parent);
	key_put(key);

	_leave(" = 0 [bad]");
	return 0;
}

/*
 * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
 * sleep)
 * - called from dput() when d_count is going to 0.
 * - return 1 to request dentry be unhashed, 0 otherwise
 */
static int afs_d_delete(const struct dentry *dentry)
{
	_enter("%pd", dentry);

	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
		goto zap;

	if (d_really_is_positive(dentry) &&
	    (test_bit(AFS_VNODE_DELETED,   &AFS_FS_I(d_inode(dentry))->flags) ||
	     test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
		goto zap;

	_leave(" = 0 [keep]");
	return 0;

zap:
	_leave(" = 1 [zap]");
	return 1;
}
Esempio n. 12
0
/*
 * check the permissions on an AFS file
 * - AFS ACLs are attached to directories only, and a file is controlled by its
 *   parent directory's ACL
 */
int afs_permission(struct inode *inode, int mask)
{
	struct afs_vnode *vnode = AFS_FS_I(inode);
	afs_access_t uninitialized_var(access);
	struct key *key;
	int ret;

	_enter("{{%x:%u},%lx},%x,",
	       vnode->fid.vid, vnode->fid.vnode, vnode->flags, mask);

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		return PTR_ERR(key);
	}

	/* if the promise has expired, we need to check the server again */
	if (!vnode->cb_promised) {
		_debug("not promised");
		ret = afs_vnode_fetch_status(vnode, NULL, key);
		if (ret < 0)
			goto error;
		_debug("new promise [fl=%lx]", vnode->flags);
	}

	/* check the permits to see if we've got one yet */
	ret = afs_check_permit(vnode, key, &access);
	if (ret < 0)
		goto error;

	/* interpret the access mask */
	_debug("REQ %x ACC %x on %s",
	       mask, access, S_ISDIR(inode->i_mode) ? "dir" : "file");

	if (S_ISDIR(inode->i_mode)) {
		if (mask & MAY_EXEC) {
			if (!(access & AFS_ACE_LOOKUP))
				goto permission_denied;
		} else if (mask & MAY_READ) {
			if (!(access & AFS_ACE_READ))
				goto permission_denied;
		} else if (mask & MAY_WRITE) {
			if (!(access & (AFS_ACE_DELETE | /* rmdir, unlink, rename from */
					AFS_ACE_INSERT | /* create, mkdir, symlink, rename to */
					AFS_ACE_WRITE))) /* chmod */
				goto permission_denied;
		} else {
			BUG();
		}
	} else {
		if (!(access & AFS_ACE_LOOKUP))
			goto permission_denied;
		if (mask & (MAY_EXEC | MAY_READ)) {
			if (!(access & AFS_ACE_READ))
				goto permission_denied;
		} else if (mask & MAY_WRITE) {
			if (!(access & AFS_ACE_WRITE))
				goto permission_denied;
		}
	}

	key_put(key);
	ret = generic_permission(inode, mask, NULL);
	_leave(" = %d", ret);
	return ret;

permission_denied:
	ret = -EACCES;
error:
	key_put(key);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 13
0
/*
 * check that a dentry lookup hit has found a valid entry
 * - NOTE! the hit can be a negative hit too, so we can't assume we have an
 *   inode
 */
static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
	struct afs_vnode *vnode, *dir;
	struct afs_fid uninitialized_var(fid);
	struct dentry *parent;
	struct key *key;
	void *dir_version;
	int ret;

	if (nd->flags & LOOKUP_RCU)
		return -ECHILD;

	vnode = AFS_FS_I(dentry->d_inode);

	if (dentry->d_inode)
		_enter("{v={%x:%u} n=%s fl=%lx},",
		       vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
		       vnode->flags);
	else
		_enter("{neg n=%s}", dentry->d_name.name);

	key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
	if (IS_ERR(key))
		key = NULL;

	/* lock down the parent dentry so we can peer at it */
	parent = dget_parent(dentry);
	if (!parent->d_inode)
		goto out_bad;

	dir = AFS_FS_I(parent->d_inode);

	/* validate the parent directory */
	if (test_bit(AFS_VNODE_MODIFIED, &dir->flags))
		afs_validate(dir, key);

	if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
		_debug("%s: parent dir deleted", dentry->d_name.name);
		goto out_bad;
	}

	dir_version = (void *) (unsigned long) dir->status.data_version;
	if (dentry->d_fsdata == dir_version)
		goto out_valid; /* the dir contents are unchanged */

	_debug("dir modified");

	/* search the directory for this vnode */
	ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key);
	switch (ret) {
	case 0:
		/* the filename maps to something */
		if (!dentry->d_inode)
			goto out_bad;
		if (is_bad_inode(dentry->d_inode)) {
			printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n",
			       parent->d_name.name, dentry->d_name.name);
			goto out_bad;
		}

		/* if the vnode ID has changed, then the dirent points to a
		 * different file */
		if (fid.vnode != vnode->fid.vnode) {
			_debug("%s: dirent changed [%u != %u]",
			       dentry->d_name.name, fid.vnode,
			       vnode->fid.vnode);
			goto not_found;
		}

		/* if the vnode ID uniqifier has changed, then the file has
		 * been deleted and replaced, and the original vnode ID has
		 * been reused */
		if (fid.unique != vnode->fid.unique) {
			_debug("%s: file deleted (uq %u -> %u I:%u)",
			       dentry->d_name.name, fid.unique,
			       vnode->fid.unique,
			       dentry->d_inode->i_generation);
			spin_lock(&vnode->lock);
			set_bit(AFS_VNODE_DELETED, &vnode->flags);
			spin_unlock(&vnode->lock);
			goto not_found;
		}
		goto out_valid;

	case -ENOENT:
		/* the filename is unknown */
		_debug("%s: dirent not found", dentry->d_name.name);
		if (dentry->d_inode)
			goto not_found;
		goto out_valid;

	default:
		_debug("failed to iterate dir %s: %d",
		       parent->d_name.name, ret);
		goto out_bad;
	}

out_valid:
	dentry->d_fsdata = dir_version;
out_skip:
	dput(parent);
	key_put(key);
	_leave(" = 1 [valid]");
	return 1;

	/* the dirent, if it exists, now points to a different vnode */
not_found:
	spin_lock(&dentry->d_lock);
	dentry->d_flags |= DCACHE_NFSFS_RENAMED;
	spin_unlock(&dentry->d_lock);

out_bad:
	if (dentry->d_inode) {
		/* don't unhash if we have submounts */
		if (have_submounts(dentry))
			goto out_skip;
	}

	_debug("dropping dentry %s/%s",
	       parent->d_name.name, dentry->d_name.name);
	shrink_dcache_parent(dentry);
	d_drop(dentry);
	dput(parent);
	key_put(key);

	_leave(" = 0 [bad]");
	return 0;
}
Esempio n. 14
0
/*
 * look up an entry in a directory
 */
static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
				 struct nameidata *nd)
{
	struct afs_vnode *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	vnode = AFS_FS_I(dir);

	_enter("{%x:%u},%p{%s},",
	       vnode->fid.vid, vnode->fid.vnode, dentry, dentry->d_name.name);

	ASSERTCMP(dentry->d_inode, ==, NULL);

	if (dentry->d_name.len >= AFSNAMEMAX) {
		_leave(" = -ENAMETOOLONG");
		return ERR_PTR(-ENAMETOOLONG);
	}

	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
		_leave(" = -ESTALE");
		return ERR_PTR(-ESTALE);
	}

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		return ERR_CAST(key);
	}

	ret = afs_validate(vnode, key);
	if (ret < 0) {
		key_put(key);
		_leave(" = %d [val]", ret);
		return ERR_PTR(ret);
	}

	ret = afs_do_lookup(dir, dentry, &fid, key);
	if (ret < 0) {
		inode = afs_try_auto_mntpt(ret, dentry, dir, key, &fid);
		if (!IS_ERR(inode)) {
			key_put(key);
			goto success;
		}

		ret = PTR_ERR(inode);
		key_put(key);
		if (ret == -ENOENT) {
			d_add(dentry, NULL);
			_leave(" = NULL [negative]");
			return NULL;
		}
		_leave(" = %d [do]", ret);
		return ERR_PTR(ret);
	}
	dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version;

	/* instantiate the dentry */
	inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL);
	key_put(key);
	if (IS_ERR(inode)) {
		_leave(" = %ld", PTR_ERR(inode));
		return ERR_CAST(inode);
	}

success:
	d_add(dentry, inode);
	_leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%u }",
	       fid.vnode,
	       fid.unique,
	       dentry->d_inode->i_ino,
	       dentry->d_inode->i_generation);

	return NULL;
}
Esempio n. 15
0
/*
 * create a symlink in an AFS filesystem
 */
static int afs_symlink(struct inode *dir, struct dentry *dentry,
		       const char *content)
{
	struct afs_file_status status;
	struct afs_server *server;
	struct afs_vnode *dvnode, *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%s},%s",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name,
	       content);

	ret = -ENAMETOOLONG;
	if (dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	ret = -EINVAL;
	if (strlen(content) >= AFSPATHMAX)
		goto error;

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content,
				&fid, &status, &server);
	if (ret < 0)
		goto create_error;

	inode = afs_iget(dir->i_sb, key, &fid, &status, NULL);
	if (IS_ERR(inode)) {
		/* ENOMEM at a really inconvenient time - just abandon the new
		 * directory on the server */
		ret = PTR_ERR(inode);
		goto iget_error;
	}

	/* apply the status report we've got for the new vnode */
	vnode = AFS_FS_I(inode);
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);
	afs_vnode_finalise_status_update(vnode, server);
	afs_put_server(server);

	d_instantiate(dentry, inode);
	if (d_unhashed(dentry)) {
		_debug("not hashed");
		d_rehash(dentry);
	}
	key_put(key);
	_leave(" = 0");
	return 0;

iget_error:
	afs_put_server(server);
create_error:
	key_put(key);
error:
	d_drop(dentry);
	_leave(" = %d", ret);
	return ret;
}
int afs_permission(struct inode *inode, int mask)
{
	struct afs_vnode *vnode = AFS_FS_I(inode);
	afs_access_t uninitialized_var(access);
	struct key *key;
	int ret;

	if (mask & MAY_NOT_BLOCK)
		return -ECHILD;

	_enter("{{%x:%u},%lx},%x,",
	       vnode->fid.vid, vnode->fid.vnode, vnode->flags, mask);

	key = afs_request_key(vnode->volume->cell);
	if (IS_ERR(key)) {
		_leave(" = %ld [key]", PTR_ERR(key));
		return PTR_ERR(key);
	}

	
	if (!vnode->cb_promised) {
		_debug("not promised");
		ret = afs_vnode_fetch_status(vnode, NULL, key);
		if (ret < 0)
			goto error;
		_debug("new promise [fl=%lx]", vnode->flags);
	}

	
	ret = afs_check_permit(vnode, key, &access);
	if (ret < 0)
		goto error;

	
	_debug("REQ %x ACC %x on %s",
	       mask, access, S_ISDIR(inode->i_mode) ? "dir" : "file");

	if (S_ISDIR(inode->i_mode)) {
		if (mask & MAY_EXEC) {
			if (!(access & AFS_ACE_LOOKUP))
				goto permission_denied;
		} else if (mask & MAY_READ) {
			if (!(access & AFS_ACE_READ))
				goto permission_denied;
		} else if (mask & MAY_WRITE) {
			if (!(access & (AFS_ACE_DELETE | 
					AFS_ACE_INSERT | 
					AFS_ACE_WRITE))) 
				goto permission_denied;
		} else {
			BUG();
		}
	} else {
		if (!(access & AFS_ACE_LOOKUP))
			goto permission_denied;
		if (mask & (MAY_EXEC | MAY_READ)) {
			if (!(access & AFS_ACE_READ))
				goto permission_denied;
		} else if (mask & MAY_WRITE) {
			if (!(access & AFS_ACE_WRITE))
				goto permission_denied;
		}
	}

	key_put(key);
	ret = generic_permission(inode, mask);
	_leave(" = %d", ret);
	return ret;

permission_denied:
	ret = -EACCES;
error:
	key_put(key);
	_leave(" = %d", ret);
	return ret;
}
Esempio n. 17
0
/*
 * AFS read page from file, directory or symlink
 */
static int afs_readpage(struct file *file, struct page *page)
{
	struct afs_vnode *vnode;
	struct inode *inode;
	struct key *key;
	size_t len;
	off_t offset;
	int ret;

	inode = page->mapping->host;

	if (file) {
		key = file->private_data;
		ASSERT(key != NULL);
	} else {
		key = afs_request_key(AFS_FS_S(inode->i_sb)->volume->cell);
		if (IS_ERR(key)) {
			ret = PTR_ERR(key);
			goto error_nokey;
		}
	}

	_enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index);

	vnode = AFS_FS_I(inode);

	BUG_ON(!PageLocked(page));

	ret = -ESTALE;
	if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
		goto error;

	/* is it cached? */
#ifdef CONFIG_AFS_FSCACHE
	ret = fscache_read_or_alloc_page(vnode->cache,
					 page,
					 afs_file_readpage_read_complete,
					 NULL,
					 GFP_KERNEL);
#else
	ret = -ENOBUFS;
#endif
	switch (ret) {
		/* read BIO submitted (page in cache) */
	case 0:
		break;

		/* page not yet cached */
	case -ENODATA:
		_debug("cache said ENODATA");
		goto go_on;

		/* page will not be cached */
	case -ENOBUFS:
		_debug("cache said ENOBUFS");
	default:
	go_on:
		offset = page->index << PAGE_CACHE_SHIFT;
		len = min_t(size_t, i_size_read(inode) - offset, PAGE_SIZE);

		/* read the contents of the file from the server into the
		 * page */
		ret = afs_vnode_fetch_data(vnode, key, offset, len, page);
		if (ret < 0) {
			if (ret == -ENOENT) {
				_debug("got NOENT from server"
				       " - marking file deleted and stale");
				set_bit(AFS_VNODE_DELETED, &vnode->flags);
				ret = -ESTALE;
			}

#ifdef CONFIG_AFS_FSCACHE
			fscache_uncache_page(vnode->cache, page);
#endif
			BUG_ON(PageFsCache(page));
			goto error;
		}

		SetPageUptodate(page);

		/* send the page to the cache */
#ifdef CONFIG_AFS_FSCACHE
		if (PageFsCache(page) &&
		    fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) {
			fscache_uncache_page(vnode->cache, page);
			BUG_ON(PageFsCache(page));
		}
#endif
		unlock_page(page);
	}

	if (!file)
		key_put(key);
	_leave(" = 0");
	return 0;

error:
	SetPageError(page);
	unlock_page(page);
	if (!file)
		key_put(key);
error_nokey:
	_leave(" = %d", ret);
	return ret;
}