/* * 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/slab.h> #include <linux/fs.h> #include <linux/pagemap.h> #include <linux/sched.h> #include "internal.h" struct afs_iget_data { struct afs_fid fid; struct afs_volume *volume; /* volume on which resides */ }; /* * map the AFS file status to the inode member variables */ static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key) { struct inode *inode = AFS_VNODE_TO_I(vnode); _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu", vnode->status.type, vnode->status.nlink, (unsigned long long) vnode->status.size, vnode->status.data_version, vnode->status.mode); switch (vnode->status.type) { case AFS_FTYPE_FILE: inode->i_mode = S_IFREG | vnode->status.mode; inode->i_op = &afs_file_inode_operations; inode->i_fop = &afs_file_operations; break; case AFS_FTYPE_DIR: inode->i_mode = S_IFDIR | vnode->status.mode; inode->i_op = &afs_dir_inode_operations; inode->i_fop = &afs_dir_file_operations; break; case AFS_FTYPE_SYMLINK: inode->i_mode = S_IFLNK | vnode->status.mode; inode->i_op = &page_symlink_inode_operations; break; default: printk("kAFS: AFS vnode with undefined type\n"); return -EBADMSG; } inode->i_nlink = vnode->status.nlink; inode->i_uid = vnode->status.owner; inode->i_gid = 0; inode->i_size = vnode->status.size; inode->i_ctime.tv_sec = vnode->status.mtime_server; inode->i_ctime.tv_nsec = 0; inode->i_atime = inode->i_mtime = inode->i_ctime; inode->i_blocks = 0; inode->i_version = vnode->fid.unique; inode->i_mapping->a_ops = &afs_fs_aops; /* check to see whether a symbolic link is really a mountpoint */ if (vnode->status.type == AFS_FTYPE_SYMLINK) { afs_mntpt_check_symlink(vnode, key); if (test_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags)) { inode->i_mode = S_IFDIR | vnode->status.mode; inode->i_op = &afs_mntpt_inode_operations; inode->i_fop = &afs_mntpt_file_operations; } } return 0; } /* * iget5() comparator */ static int afs_iget5_test(struct inode *inode, void *opaque) { struct afs_iget_data *data = opaque; return inode->i_ino == data->fid.vnode && inode->i_version == data->fid.unique; } /* * iget5() inode initialiser */ static int afs_iget5_set(struct inode *inode, void *opaque) { struct afs_iget_data *data = opaque; struct afs_vnode *vnode = AFS_FS_I(inode); inode->i_ino = data->fid.vnode; inode->i_version = data->fid.unique; vnode->fid = data->fid; vnode->volume = data->volume; return 0; } /* * inode retrieval */ struct inode *afs_iget(struct super_block *sb, struct key *key, struct afs_fid *fid, struct afs_file_status *status, struct afs_callback *cb) { struct afs_iget_data data = { .fid = *fid }; struct afs_super_info *as; struct afs_vnode *vnode; struct inode *inode; int ret; _enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique); as = sb->s_fs_info; data.volume = as->volume; inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set, &data); if (!inode) { _leave(" = -ENOMEM"); return ERR_PTR(-ENOMEM); } _debug("GOT INODE %p { vl=%x vn=%x, u=%x }", inode, fid->vid, fid->vnode, fid->unique); vnode = AFS_FS_I(inode); /* deal with an existing inode */ if (!(inode->i_state & I_NEW)) { _leave(" = %p", inode); return inode; } #ifdef AFS_CACHING_SUPPORT /* set up caching before reading the status, as fetch-status reads the * first page of symlinks to see if they're really mntpts */ cachefs_acquire_cookie(vnode->volume->cache, NULL, vnode, &vnode->cache); #endif if (!status) { /* it's a remotely extant inode */ set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags); ret = afs_vnode_fetch_status(vnode, NULL, key); if (ret < 0) goto bad_inode; } else { /* it's an inode we just created */ memcpy(&vnode->status, status, sizeof(vnode->status)); if (!cb) { /* it's a symlink we just created (the fileserver * didn't give us a callback) */ vnode->cb_version = 0; vnode->cb_expiry = 0; vnode->cb_type = 0; vnode->cb_expires = get_seconds(); } else { vnode->cb_version = cb->version; vnode->cb_expiry = cb->expiry; vnode->cb_type = cb->type; vnode->cb_expires = vnode->cb_expiry + get_seconds(); } } ret = afs_inode_map_status(vnode, key); if (ret < 0) goto bad_inode; /* success */ clear_bit(AFS_VNODE_UNSET, &vnode->flags); inode->i_flags |= S_NOATIME; unlock_new_inode(inode); _leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type); return inode; /* failure */ bad_inode: iget_failed(inode); _leave(" = %d [bad]", ret); return ERR_PTR(ret); } /* * mark the data attached to an inode as obsolete due to a write on the server * - might also want to ditch all the outstanding writes and dirty pages */ void afs_zap_data(struct afs_vnode *vnode) { _enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode); /* nuke all the non-dirty pages that aren't locked, mapped or being * written back in a regular file and completely discard the pages in a * directory or symlink */ if (S_ISREG(vnode->vfs_inode.i_mode)) invalidate_remote_inode(&vnode->vfs_inode); else invalidate_inode_pages2(vnode->vfs_inode.i_mapping); } /* * validate a vnode/inode * - there are several things we need to check * - parent dir data changes (rm, rmdir, rename, mkdir, create, link, * symlink) * - parent dir metadata changed (security changes) * - dentry data changed (write, truncate) * - dentry metadata changed (security changes) */ int afs_validate(struct afs_vnode *vnode, struct key *key) { int ret; _enter("{v={%x:%u} fl=%lx},%x", vnode->fid.vid, vnode->fid.vnode, vnode->flags, key_serial(key)); if (vnode->cb_promised && !test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) && !test_bit(AFS_VNODE_MODIFIED, &vnode->flags) && !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) { if (vnode->cb_expires < get_seconds() + 10) { _debug("callback expired"); set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags); } else { goto valid; } } if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) goto valid; mutex_lock(&vnode->validate_lock); /* if the promise has expired, we need to check the server again to get * a new promise - note that if the (parent) directory's metadata was * changed then the security may be different and we may no longer have * access */ if (!vnode->cb_promised || test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) { _debug("not promised"); ret = afs_vnode_fetch_status(vnode, NULL, key); if (ret < 0) goto error_unlock; _debug("new promise [fl=%lx]", vnode->flags); } if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { _debug("file already deleted"); ret = -ESTALE; goto error_unlock; } /* if the vnode's data version number changed then its contents are * different */ if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) afs_zap_data(vnode); clear_bit(AFS_VNODE_MODIFIED, &vnode->flags); mutex_unlock(&vnode->validate_lock); valid: _leave(" = 0"); return 0; error_unlock: mutex_unlock(&vnode->validate_lock); _leave(" = %d", ret); return ret; } /* * read the attributes of an inode */ int afs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { struct inode *inode; inode = dentry->d_inode; _enter("{ ino=%lu v=%llu }", inode->i_ino, (unsigned long long)inode->i_version); generic_fillattr(inode, stat); return 0; } /* * clear an AFS inode */ void afs_clear_inode(struct inode *inode) { struct afs_permits *permits; struct afs_vnode *vnode; vnode = AFS_FS_I(inode); _enter("{%x:%u.%d} v=%u x=%u t=%u }", vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique, vnode->cb_version, vnode->cb_expiry, vnode->cb_type); _debug("CLEAR INODE %p", inode); ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode); afs_give_up_callback(vnode); if (vnode->server) { spin_lock(&vnode->server->fs_lock); rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes); spin_unlock(&vnode->server->fs_lock); afs_put_server(vnode->server); vnode->server = NULL; } ASSERT(list_empty(&vnode->writebacks)); ASSERT(!vnode->cb_promised); #ifdef AFS_CACHING_SUPPORT cachefs_relinquish_cookie(vnode->cache, 0); vnode->cache = NULL; #endif mutex_lock(&vnode->permits_lock); permits = vnode->permits; rcu_assign_pointer(vnode->permits, NULL); mutex_unlock(&vnode->permits_lock); if (permits) call_rcu(&permits->rcu, afs_zap_permits); _leave(""); } /* * set the attributes of an inode */ int afs_setattr(struct dentry *dentry, struct iattr *attr) { struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode); struct key *key; int ret; _enter("{%x:%u},{n=%s},%x", vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name, 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; }