path: root/fs/afs/inode.c

/*
 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
 *
 * This software may be freely redistributed under the terms of the
 * GNU General Public License.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Authors: David Woodhouse <dwmw2@infradead.org>
 *          David Howells <dhowells@redhat.com>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/sched.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/iversion.h>
#include "internal.h"
#include "afs_fs.h"

static const struct inode_operations afs_symlink_inode_operations = {
	.get_link	= page_get_link,
};

static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
{
	static unsigned long once_only;

	pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);
	pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
		vnode->status.abort_code,
		vnode->status.mode,
		vnode->status.size,
		vnode->status.data_version);
	pr_warn("kAFS: vnode %llx:%llx:%x\n",
		vnode->fid.vid,
		vnode->fid.vnode,
		vnode->fid.unique);
	if (parent_vnode)
		pr_warn("kAFS: dir %llx:%llx:%x\n",
			parent_vnode->fid.vid,
			parent_vnode->fid.vnode,
			parent_vnode->fid.unique);

	if (!test_and_set_bit(0, &once_only))
		dump_stack();
}

/*
 * Set parameters for the netfs library
 */
static void afs_set_netfs_context(struct afs_vnode *vnode)
{
	netfs_inode_init(&vnode->netfs, &afs_req_ops);
}

/*
 * Initialise an inode from the vnode status.
 */
static int afs_inode_init_from_status(struct afs_operation *op,
				      struct afs_vnode_param *vp,
				      struct afs_vnode *vnode)
{
	struct afs_file_status *status = &vp->scb.status;
	struct inode *inode = AFS_VNODE_TO_I(vnode);
	struct timespec64 t;

	_enter("{%llx:%llu.%u} %s",
	       vp->fid.vid, vp->fid.vnode, vp->fid.unique,
	       op->type ? op->type->name : "???");

	_debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
	       status->type,
	       status->nlink,
	       (unsigned long long) status->size,
	       status->data_version,
	       status->mode);

	write_seqlock(&vnode->cb_lock);

	vnode->cb_v_break = op->cb_v_break;
	vnode->cb_s_break = op->cb_s_break;
	vnode->status = *status;

	t = status->mtime_client;
	inode->i_ctime = t;
	inode->i_mtime = t;
	inode->i_atime = t;
	inode->i_flags |= S_NOATIME;
	inode->i_uid = make_kuid(&init_user_ns, status->owner);
	inode->i_gid = make_kgid(&init_user_ns, status->group);
	set_nlink(&vnode->netfs.inode, status->nlink);

	switch (status->type) {
	case AFS_FTYPE_FILE:
		inode->i_mode	= S_IFREG | (status->mode & S_IALLUGO);
		inode->i_op	= &afs_file_inode_operations;
		inode->i_fop	= &afs_file_operations;
		inode->i_mapping->a_ops	= &afs_file_aops;
		mapping_set_large_folios(inode->i_mapping);
		break;
	case AFS_FTYPE_DIR:
		inode->i_mode	= S_IFDIR |  (status->mode & S_IALLUGO);
		inode->i_op	= &afs_dir_inode_operations;
		inode->i_fop	= &afs_dir_file_operations;
		inode->i_mapping->a_ops	= &afs_dir_aops;
		mapping_set_large_folios(inode->i_mapping);
		break;
	case AFS_FTYPE_SYMLINK:
		/* Symlinks with a mode of 0644 are actually mountpoints. */
		if ((status->mode & 0777) == 0644) {
			inode->i_flags |= S_AUTOMOUNT;

			set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);

			inode->i_mode	= S_IFDIR | 0555;
			inode->i_op	= &afs_mntpt_inode_operations;
			inode->i_fop	= &afs_mntpt_file_operations;
			inode->i_mapping->a_ops	= &afs_symlink_aops;
		} else {
			inode->i_mode	= S_IFLNK | status->mode;
			inode->i_op	= &afs_symlink_inode_operations;
			inode->i_mapping->a_ops	= &afs_symlink_aops;
		}
		inode_nohighmem(inode);
		break;
	default:
		dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
		write_sequnlock(&vnode->cb_lock);
		return afs_protocol_error(NULL, afs_eproto_file_type);
	}

	afs_set_i_size(vnode, status->size);
	afs_set_netfs_context(vnode);

	vnode->invalid_before	= status->data_version;
	inode_set_iversion_raw(&vnode->netfs.inode, status->data_version);

	if (!vp->scb.have_cb) {
		/* it's a symlink we just created (the fileserver
		 * didn't give us a callback) */
		vnode->cb_expires_at = ktime_get_real_seconds();
	} else {
		vnode->cb_expires_at = vp->scb.callback.expires_at;
		vnode->cb_server = op->server;
		set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
	}

	write_sequnlock(&vnode->cb_lock);
	return 0;
}

/*
 * Update the core inode struct from a returned status record.
 */
static void afs_apply_status(struct afs_operation *op,
			     struct afs_vnode_param *vp)
{
	struct afs_file_status *status = &vp->scb.status;
	struct afs_vnode *vnode = vp->vnode;
	struct inode *inode = &vnode->netfs.inode;
	struct timespec64 t;
	umode_t mode;
	bool data_changed =<