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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/afs/inode.c
Initial import
Diffstat (limited to 'fs/afs/inode.c')
-rw-r--r--fs/afs/inode.c498
1 files changed, 498 insertions, 0 deletions
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
new file mode 100644
index 000000000..e06f5a233
--- /dev/null
+++ b/fs/afs/inode.c
@@ -0,0 +1,498 @@
+/*
+ * 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 "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;
+ }
+
+#ifdef CONFIG_AFS_FSCACHE
+ if (vnode->status.size != inode->i_size)
+ fscache_attr_changed(vnode->cache);
+#endif
+
+ set_nlink(inode, vnode->status.nlink);
+ inode->i_uid = vnode->status.owner;
+ inode->i_gid = GLOBAL_ROOT_GID;
+ 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_generation = vnode->fid.unique;
+ inode->i_version = vnode->status.data_version;
+ 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_generation == data->fid.unique;
+}
+
+/*
+ * iget5() comparator for inode created by autocell operations
+ *
+ * These pseudo inodes don't match anything.
+ */
+static int afs_iget5_autocell_test(struct inode *inode, void *opaque)
+{
+ return 0;
+}
+
+/*
+ * 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_generation = data->fid.unique;
+ vnode->fid = data->fid;
+ vnode->volume = data->volume;
+
+ return 0;
+}
+
+/*
+ * inode retrieval for autocell
+ */
+struct inode *afs_iget_autocell(struct inode *dir, const char *dev_name,
+ int namesz, struct key *key)
+{
+ struct afs_iget_data data;
+ struct afs_super_info *as;
+ struct afs_vnode *vnode;
+ struct super_block *sb;
+ struct inode *inode;
+ static atomic_t afs_autocell_ino;
+
+ _enter("{%x:%u},%*.*s,",
+ AFS_FS_I(dir)->fid.vid, AFS_FS_I(dir)->fid.vnode,
+ namesz, namesz, dev_name ?: "");
+
+ sb = dir->i_sb;
+ as = sb->s_fs_info;
+ data.volume = as->volume;
+ data.fid.vid = as->volume->vid;
+ data.fid.unique = 0;
+ data.fid.vnode = 0;
+
+ inode = iget5_locked(sb, atomic_inc_return(&afs_autocell_ino),
+ afs_iget5_autocell_test, afs_iget5_set,
+ &data);
+ if (!inode) {
+ _leave(" = -ENOMEM");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ _debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
+ inode, inode->i_ino, data.fid.vid, data.fid.vnode,
+ data.fid.unique);
+
+ vnode = AFS_FS_I(inode);
+
+ /* there shouldn't be an existing inode */
+ BUG_ON(!(inode->i_state & I_NEW));
+
+ inode->i_size = 0;
+ inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ inode->i_op = &afs_autocell_inode_operations;
+ set_nlink(inode, 2);
+ inode->i_uid = GLOBAL_ROOT_UID;
+ inode->i_gid = GLOBAL_ROOT_GID;
+ inode->i_ctime.tv_sec = get_seconds();
+ inode->i_ctime.tv_nsec = 0;
+ inode->i_atime = inode->i_mtime = inode->i_ctime;
+ inode->i_blocks = 0;
+ inode->i_version = 0;
+ inode->i_generation = 0;
+
+ set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
+ set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
+ inode->i_flags |= S_AUTOMOUNT | S_NOATIME;
+ unlock_new_inode(inode);
+ _leave(" = %p", inode);
+ return inode;
+}
+
+/*
+ * 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;
+ }
+
+ 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();
+ }
+ }
+
+ /* set up caching before mapping the status, as map-status reads the
+ * first page of symlinks to see if they're really mountpoints */
+ inode->i_size = vnode->status.size;
+#ifdef CONFIG_AFS_FSCACHE
+ vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
+ &afs_vnode_cache_index_def,
+ vnode, true);
+#endif
+
+ 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:
+#ifdef CONFIG_AFS_FSCACHE
+ fscache_relinquish_cookie(vnode->cache, 0);
+ vnode->cache = NULL;
+#endif
+ 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 = d_inode(dentry);
+
+ _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
+
+ generic_fillattr(inode, stat);
+ return 0;
+}
+
+/*
+ * discard an AFS inode
+ */
+int afs_drop_inode(struct inode *inode)
+{
+ _enter("");
+
+ if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
+ return generic_delete_inode(inode);
+ else
+ return generic_drop_inode(inode);
+}
+
+/*
+ * clear an AFS inode
+ */
+void afs_evict_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);
+
+ truncate_inode_pages_final(&inode->i_data);
+ clear_inode(inode);
+
+ 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 CONFIG_AFS_FSCACHE
+ fscache_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(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;
+}