--- /dev/null
+/*
+ * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/jhash.h>
+#include <linux/namei.h>
+#include <linux/pagemap.h>
+
+#include "netfs.h"
+
+static int pohmelfs_cmp_hash(struct pohmelfs_name *n, u32 hash)
+{
+ if (n->hash > hash)
+ return -1;
+ if (n->hash < hash)
+ return 1;
+
+ return 0;
+}
+
+static struct pohmelfs_name *pohmelfs_search_hash_unprecise(struct pohmelfs_inode *pi, u32 hash)
+{
+ struct rb_node *n = pi->hash_root.rb_node;
+ struct pohmelfs_name *tmp = NULL;
+ int cmp;
+
+ while (n) {
+ tmp = rb_entry(n, struct pohmelfs_name, hash_node);
+
+ cmp = pohmelfs_cmp_hash(tmp, hash);
+ if (cmp < 0)
+ n = n->rb_left;
+ else if (cmp > 0)
+ n = n->rb_right;
+ else
+ break;
+
+ }
+
+ return tmp;
+}
+
+struct pohmelfs_name *pohmelfs_search_hash(struct pohmelfs_inode *pi, u32 hash)
+{
+ struct pohmelfs_name *tmp;
+
+ tmp = pohmelfs_search_hash_unprecise(pi, hash);
+ if (tmp && (tmp->hash == hash))
+ return tmp;
+
+ return NULL;
+}
+
+static void __pohmelfs_name_del(struct pohmelfs_inode *parent, struct pohmelfs_name *node)
+{
+ rb_erase(&node->hash_node, &parent->hash_root);
+}
+
+/*
+ * Remove name cache entry from its caches and free it.
+ */
+static void pohmelfs_name_free(struct pohmelfs_inode *parent, struct pohmelfs_name *node)
+{
+ __pohmelfs_name_del(parent, node);
+ list_del(&node->sync_create_entry);
+ kfree(node);
+}
+
+static struct pohmelfs_name *pohmelfs_insert_hash(struct pohmelfs_inode *pi,
+ struct pohmelfs_name *new)
+{
+ struct rb_node **n = &pi->hash_root.rb_node, *parent = NULL;
+ struct pohmelfs_name *ret = NULL, *tmp;
+ int cmp;
+
+ while (*n) {
+ parent = *n;
+
+ tmp = rb_entry(parent, struct pohmelfs_name, hash_node);
+
+ cmp = pohmelfs_cmp_hash(tmp, new->hash);
+ if (cmp < 0)
+ n = &parent->rb_left;
+ else if (cmp > 0)
+ n = &parent->rb_right;
+ else {
+ ret = tmp;
+ break;
+ }
+ }
+
+ if (ret) {
+ printk("%s: exist: parent: %llu, ino: %llu, hash: %x, len: %u, data: '%s', "
+ "new: ino: %llu, hash: %x, len: %u, data: '%s'.\n",
+ __func__, pi->ino,
+ ret->ino, ret->hash, ret->len, ret->data,
+ new->ino, new->hash, new->len, new->data);
+ ret->ino = new->ino;
+ return ret;
+ }
+
+ rb_link_node(&new->hash_node, parent, n);
+ rb_insert_color(&new->hash_node, &pi->hash_root);
+
+ return NULL;
+}
+
+/*
+ * Free name cache for given inode.
+ */
+void pohmelfs_free_names(struct pohmelfs_inode *parent)
+{
+ struct rb_node *rb_node;
+ struct pohmelfs_name *n;
+
+ for (rb_node = rb_first(&parent->hash_root); rb_node;) {
+ n = rb_entry(rb_node, struct pohmelfs_name, hash_node);
+ rb_node = rb_next(rb_node);
+
+ pohmelfs_name_free(parent, n);
+ }
+}
+
+static void pohmelfs_fix_offset(struct pohmelfs_inode *parent, struct pohmelfs_name *node)
+{
+ parent->total_len -= node->len;
+}
+
+/*
+ * Free name cache entry helper.
+ */
+void pohmelfs_name_del(struct pohmelfs_inode *parent, struct pohmelfs_name *node)
+{
+ pohmelfs_fix_offset(parent, node);
+ pohmelfs_name_free(parent, node);
+}
+
+/*
+ * Insert new name cache entry into all hash cache.
+ */
+static int pohmelfs_insert_name(struct pohmelfs_inode *parent, struct pohmelfs_name *n)
+{
+ struct pohmelfs_name *name;
+
+ name = pohmelfs_insert_hash(parent, n);
+ if (name)
+ return -EEXIST;
+
+ parent->total_len += n->len;
+ list_add_tail(&n->sync_create_entry, &parent->sync_create_list);
+
+ return 0;
+}
+
+/*
+ * Allocate new name cache entry.
+ */
+static struct pohmelfs_name *pohmelfs_name_alloc(unsigned int len)
+{
+ struct pohmelfs_name *n;
+
+ n = kzalloc(sizeof(struct pohmelfs_name) + len, GFP_KERNEL);
+ if (!n)
+ return NULL;
+
+ INIT_LIST_HEAD(&n->sync_create_entry);
+
+ n->data = (char *)(n+1);
+
+ return n;
+}
+
+/*
+ * Add new name entry into directory's cache.
+ */
+static int pohmelfs_add_dir(struct pohmelfs_sb *psb, struct pohmelfs_inode *parent,
+ struct pohmelfs_inode *npi, struct qstr *str, unsigned int mode, int link)
+{
+ int err = -ENOMEM;
+ struct pohmelfs_name *n;
+
+ n = pohmelfs_name_alloc(str->len + 1);
+ if (!n)
+ goto err_out_exit;
+
+ n->ino = npi->ino;
+ n->mode = mode;
+ n->len = str->len;
+ n->hash = str->hash;
+ sprintf(n->data, "%s", str->name);
+
+ mutex_lock(&parent->offset_lock);
+ err = pohmelfs_insert_name(parent, n);
+ mutex_unlock(&parent->offset_lock);
+
+ if (err) {
+ if (err != -EEXIST)
+ goto err_out_free;
+ kfree(n);
+ }
+
+ return 0;
+
+err_out_free:
+ kfree(n);
+err_out_exit:
+ return err;
+}
+
+/*
+ * Create new inode for given parameters (name, inode info, parent).
+ * This does not create object on the server, it will be synced there during writeback.
+ */
+struct pohmelfs_inode *pohmelfs_new_inode(struct pohmelfs_sb *psb,
+ struct pohmelfs_inode *parent, struct qstr *str,
+ struct netfs_inode_info *info, int link)
+{
+ struct inode *new = NULL;
+ struct pohmelfs_inode *npi;
+ int err = -EEXIST;
+
+ dprintk("%s: creating inode: parent: %llu, ino: %llu, str: %p.\n",
+ __func__, (parent)?parent->ino:0, info->ino, str);
+
+ err = -ENOMEM;
+ new = iget_locked(psb->sb, info->ino);
+ if (!new)
+ goto err_out_exit;
+
+ npi = POHMELFS_I(new);
+ npi->ino = info->ino;
+ err = 0;
+
+ if (new->i_state & I_NEW) {
+ dprintk("%s: filling VFS inode: %lu/%llu.\n",
+ __func__, new->i_ino, info->ino);
+ pohmelfs_fill_inode(new, info);
+
+ if (S_ISDIR(info->mode)) {
+ struct qstr s;
+
+ s.name = ".";
+ s.len = 1;
+ s.hash = jhash(s.name, s.len, 0);
+
+ err = pohmelfs_add_dir(psb, npi, npi, &s, info->mode, 0);
+ if (err)
+ goto err_out_put;
+
+ s.name = "..";
+ s.len = 2;
+ s.hash = jhash(s.name, s.len, 0);
+
+ err = pohmelfs_add_dir(psb, npi, (parent)?parent:npi, &s,
+ (parent)?parent->vfs_inode.i_mode:npi->vfs_inode.i_mode, 0);
+ if (err)
+ goto err_out_put;
+ }
+ }
+
+ if (str) {
+ if (parent) {
+ err = pohmelfs_add_dir(psb, parent, npi, str, info->mode, link);
+
+ dprintk("%s: %s inserted name: '%s', new_offset: %llu, ino: %llu, parent: %llu.\n",
+ __func__, (err)?"unsuccessfully":"successfully",
+ str->name, parent->total_len, info->ino, parent->ino);
+
+ if (err && err != -EEXIST)
+ goto err_out_put;
+ }
+ }
+
+ if (new->i_state & I_NEW) {
+ if (parent)
+ mark_inode_dirty(&parent->vfs_inode);
+ mark_inode_dirty(new);
+ }
+
+ set_bit(NETFS_INODE_OWNED, &npi->state);
+ npi->lock_type = POHMELFS_WRITE_LOCK;
+ unlock_new_inode(new);
+
+ return npi;
+
+err_out_put:
+ printk("%s: putting inode: %p, npi: %p, error: %d.\n", __func__, new, npi, err);
+ iput(new);
+err_out_exit:
+ return ERR_PTR(err);
+}
+
+static int pohmelfs_remote_sync_complete(struct page **pages, unsigned int page_num,
+ void *private, int err)
+{
+ struct pohmelfs_inode *pi = private;
+ struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
+
+ dprintk("%s: ino: %llu, err: %d.\n", __func__, pi->ino, err);
+
+ if (err)
+ pi->error = err;
+ wake_up(&psb->wait);
+ pohmelfs_put_inode(pi);
+
+ return err;
+}
+
+/*
+ * Receive directory content from the server.
+ * This should be only done for objects, which were not created locally,
+ * and which were not synced previously.
+ */
+static int pohmelfs_sync_remote_dir(struct pohmelfs_inode *pi)
+{
+ struct inode *inode = &pi->vfs_inode;
+ struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
+ long ret = msecs_to_jiffies(25000);
+ int err;
+
+ dprintk("%s: dir: %llu, state: %lx: remote_synced: %d.\n",
+ __func__, pi->ino, pi->state, test_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state));
+
+ if (test_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &pi->state))
+ return 0;
+
+ if (!igrab(inode)) {
+ err = -ENOENT;
+ goto err_out_exit;
+ }
+
+ err = pohmelfs_meta_command(pi, NETFS_READDIR, NETFS_TRANS_SINGLE_DST,
+ pohmelfs_remote_sync_complete, pi, 0);
+ if (err)
+ goto err_out_exit;
+
+ pi->error = 0;
+ ret = wait_event_interruptible_timeout(psb->wait,
+ test_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &pi->state) || pi->error, ret);
+ dprintk("%s: awake dir: %llu, ret: %ld, err: %d.\n", __func__, pi->ino, ret, pi->error);
+ if (ret <= 0) {
+ err = -ETIMEDOUT;
+ goto err_out_exit;
+ }
+
+ if (pi->error)
+ return pi->error;
+
+ return 0;
+
+err_out_exit:
+ clear_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
+
+ return err;
+}
+
+static int pohmelfs_dir_open(struct inode *inode, struct file *file)
+{
+ file->private_data = NULL;
+ return 0;
+}
+
+/*
+ * VFS readdir callback. Syncs directory content from server if needed,
+ * and provides direntry info to the userspace.
+ */
+static int pohmelfs_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct pohmelfs_inode *pi = POHMELFS_I(inode);
+ struct pohmelfs_name *n;
+ struct rb_node *rb_node;
+ int err = 0, mode;
+ u64 len;
+
+ dprintk("%s: parent: %llu, fpos: %llu, hash: %08lx.\n",
+ __func__, pi->ino, (u64)file->f_pos,
+ (unsigned long)file->private_data);
+
+ err = pohmelfs_data_lock(pi, 0, ~0, POHMELFS_READ_LOCK);
+ if (err)
+ return err;
+
+ err = pohmelfs_sync_remote_dir(pi);
+ if (err)
+ return err;
+
+ if (file->private_data && (file->private_data == (void *)(unsigned long)file->f_pos))
+ return 0;
+
+ mutex_lock(&pi->offset_lock);
+ n = pohmelfs_search_hash_unprecise(pi, (unsigned long)file->private_data);
+
+ while (n) {
+ mode = (n->mode >> 12) & 15;
+
+ dprintk("%s: offset: %llu, parent ino: %llu, name: '%s', len: %u, ino: %llu, "
+ "mode: %o/%o, fpos: %llu, hash: %08x.\n",
+ __func__, file->f_pos, pi->ino, n->data, n->len,
+ n->ino, n->mode, mode, file->f_pos, n->hash);
+
+ file->private_data = (void *)n->hash;
+
+ len = n->len;
+ err = filldir(dirent, n->data, n->len, file->f_pos, n->ino, mode);
+
+ if (err < 0) {
+ dprintk("%s: err: %d.\n", __func__, err);
+ err = 0;
+ break;
+ }
+
+ file->f_pos += len;
+
+ rb_node = rb_next(&n->hash_node);
+
+ if (!rb_node || (rb_node == &n->hash_node)) {
+ file->private_data = (void *)(unsigned long)file->f_pos;
+ break;
+ }
+
+ n = rb_entry(rb_node, struct pohmelfs_name, hash_node);
+ }
+ mutex_unlock(&pi->offset_lock);
+
+ return err;
+}
+
+static loff_t pohmelfs_dir_lseek(struct file *file, loff_t offset, int origin)
+{
+ file->f_pos = offset;
+ file->private_data = NULL;
+ return offset;
+}
+
+const struct file_operations pohmelfs_dir_fops = {
+ .open = pohmelfs_dir_open,
+ .read = generic_read_dir,
+ .llseek = pohmelfs_dir_lseek,
+ .readdir = pohmelfs_readdir,
+};
+
+/*
+ * Lookup single object on server.
+ */
+static int pohmelfs_lookup_single(struct pohmelfs_inode *parent,
+ struct qstr *str, u64 ino)
+{
+ struct pohmelfs_sb *psb = POHMELFS_SB(parent->vfs_inode.i_sb);
+ long ret = msecs_to_jiffies(5000);
+ int err;
+
+ set_bit(NETFS_COMMAND_PENDING, &parent->state);
+ err = pohmelfs_meta_command_data(parent, parent->ino, NETFS_LOOKUP,
+ (char *)str->name, NETFS_TRANS_SINGLE_DST, NULL, NULL, ino);
+ if (err)
+ goto err_out_exit;
+
+ err = 0;
+ ret = wait_event_interruptible_timeout(psb->wait,
+ !test_bit(NETFS_COMMAND_PENDING, &parent->state), ret);
+ if (ret == 0)
+ err = -ETIMEDOUT;
+ else if (signal_pending(current))
+ err = -EINTR;
+
+ if (err)
+ goto err_out_exit;
+
+ return 0;
+
+err_out_exit:
+ clear_bit(NETFS_COMMAND_PENDING, &parent->state);
+
+ printk("%s: failed: parent: %llu, ino: %llu, name: '%s', err: %d.\n",
+ __func__, parent->ino, ino, str->name, err);
+
+ return err;
+}
+
+/*
+ * VFS lookup callback.
+ * We first try to get inode number from local name cache, if we have one,
+ * then inode can be found in inode cache. If there is no inode or no object in
+ * local cache, try to lookup it on server. This only should be done for directories,
+ * which were not created locally, otherwise remote server does not know about dir at all,
+ * so no need to try to know that.
+ */
+struct dentry *pohmelfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+ struct pohmelfs_inode *parent = POHMELFS_I(dir);
+ struct pohmelfs_name *n;
+ struct inode *inode = NULL;
+ unsigned long ino = 0;
+ int err, lock_type = POHMELFS_READ_LOCK, need_lock;
+ struct qstr str = dentry->d_name;
+
+ if ((nd->intent.open.flags & O_ACCMODE) > 1)
+ lock_type = POHMELFS_WRITE_LOCK;
+
+ need_lock = pohmelfs_need_lock(parent, lock_type);
+
+ err = pohmelfs_data_lock(parent, 0, ~0, lock_type);
+ if (err)
+ goto out;
+
+ str.hash = jhash(dentry->d_name.name, dentry->d_name.len, 0);
+
+ mutex_lock(&parent->offset_lock);
+ n = pohmelfs_search_hash(parent, str.hash);
+ if (n)
+ ino = n->ino;
+ mutex_unlock(&parent->offset_lock);
+
+ dprintk("%s: 1 ino: %lu, inode: %p, name: '%s', hash: %x, parent_state: %lx.\n",
+ __func__, ino, inode, str.name, str.hash, parent->state);
+
+ if (ino) {
+ inode = ilookup(dir->i_sb, ino);
+ if (inode)
+ goto out;
+ }
+
+ dprintk("%s: dir: %p, dir_ino: %llu, name: '%s', len: %u, dir_state: %lx, ino: %lu.\n",
+ __func__, dir, parent->ino,
+ str.name, str.len, parent->state, ino);
+
+ if (!ino) {
+ if (!need_lock)
+ goto out;
+ }
+
+ err = pohmelfs_lookup_single(parent, &str, ino);
+ if (err)
+ goto out;
+
+ if (!ino) {
+ mutex_lock(&parent->offset_lock);
+ n = pohmelfs_search_hash(parent, str.hash);
+ if (n)
+ ino = n->ino;
+ mutex_unlock(&parent->offset_lock);
+ }
+
+ if (ino) {
+ inode = ilookup(dir->i_sb, ino);
+ printk("%s: second lookup ino: %lu, inode: %p, name: '%s', hash: %x.\n",
+ __func__, ino, inode, str.name, str.hash);
+ if (!inode) {
+ printk("%s: No inode for ino: %lu, name: '%s', hash: %x.\n",
+ __func__, ino, str.name, str.hash);
+ //return NULL;
+ return ERR_PTR(-EACCES);
+ }
+ } else {
+ printk("%s: No inode number : name: '%s', hash: %x.\n",
+ __func__, str.name, str.hash);
+ }
+out:
+ return d_splice_alias(inode, dentry);
+}
+
+/*
+ * Create new object in local cache. Object will be synced to server
+ * during writeback for given inode.
+ */
+struct pohmelfs_inode *pohmelfs_create_entry_local(struct pohmelfs_sb *psb,
+ struct pohmelfs_inode *parent, struct qstr *str, u64 start, int mode)
+{
+ struct pohmelfs_inode *npi;
+ int err = -ENOMEM;
+ struct netfs_inode_info info;
+
+ dprintk("%s: name: '%s', mode: %o, start: %llu.\n",
+ __func__, str->name, mode, start);
+
+ info.mode = mode;
+ info.ino = start;
+
+ if (!start)
+ info.ino = pohmelfs_new_ino(psb);
+
+ info.nlink = S_ISDIR(mode)?2:1;
+ info.uid = current_fsuid();
+ info.gid = current_fsgid();
+ info.size = 0;
+ info.blocksize = 512;
+ info.blocks = 0;
+ info.rdev = 0;
+ info.version = 0;
+
+ npi = pohmelfs_new_inode(psb, parent, str, &info, !!start);
+ if (IS_ERR(npi)) {
+ err = PTR_ERR(npi);
+ goto err_out_unlock;
+ }
+
+ return npi;
+
+err_out_unlock:
+ dprintk("%s: err: %d.\n", __func__, err);
+ return ERR_PTR(err);
+}
+
+/*
+ * Create local object and bind it to dentry.
+ */
+static int pohmelfs_create_entry(struct inode *dir, struct dentry *dentry, u64 start, int mode)
+{
+ struct pohmelfs_sb *psb = POHMELFS_SB(dir->i_sb);
+ struct pohmelfs_inode *npi, *parent;
+ struct qstr str = dentry->d_name;
+ int err;
+
+ parent = POHMELFS_I(dir);
+
+ err = pohmelfs_data_lock(parent, 0, ~0, POHMELFS_WRITE_LOCK);
+ if (err)
+ return err;
+
+ str.hash = jhash(dentry->d_name.name, dentry->d_name.len, 0);
+
+ npi = pohmelfs_create_entry_local(psb, parent, &str, start, mode);
+ if (IS_ERR(npi))
+ return PTR_ERR(npi);
+
+ d_instantiate(dentry, &npi->vfs_inode);
+
+ dprintk("%s: parent: %llu, inode: %llu, name: '%s', parent_nlink: %d, nlink: %d.\n",
+ __func__, parent->ino, npi->ino, dentry->d_name.name,
+ (signed)dir->i_nlink, (signed)npi->vfs_inode.i_nlink);
+
+ return 0;
+}
+
+/*
+ * VFS create and mkdir callbacks.
+ */
+static int pohmelfs_create(struct inode *dir, struct dentry *dentry, int mode,
+ struct nameidata *nd)
+{
+ return pohmelfs_create_entry(dir, dentry, 0, mode);
+}
+
+static int pohmelfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ int err;
+
+ inode_inc_link_count(dir);
+ err = pohmelfs_create_entry(dir, dentry, 0, mode | S_IFDIR);
+ if (err)
+ inode_dec_link_count(dir);
+
+ return err;
+}
+
+static int pohmelfs_remove_entry(struct inode *dir, struct dentry *dentry)
+{
+ struct pohmelfs_sb *psb = POHMELFS_SB(dir->i_sb);
+ struct inode *inode = dentry->d_inode;
+ struct pohmelfs_inode *parent = POHMELFS_I(dir), *pi = POHMELFS_I(inode);
+ struct pohmelfs_name *n;
+ int err = -ENOENT;
+ struct qstr str = dentry->d_name;
+
+ err = pohmelfs_data_lock(parent, 0, ~0, POHMELFS_WRITE_LOCK);
+ if (err)
+ return err;
+
+ str.hash = jhash(dentry->d_name.name, dentry->d_name.len, 0);
+
+ dprintk("%s: dir_ino: %llu, inode: %llu, name: '%s', nlink: %d.\n",
+ __func__, parent->ino, pi->ino,
+ str.name, (signed)inode->i_nlink);
+
+ BUG_ON(!inode);
+
+ mutex_lock(&parent->offset_lock);
+ n = pohmelfs_search_hash(parent, str.hash);
+ if (n) {
+ pohmelfs_fix_offset(parent, n);
+ if (test_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state)) {
+ pohmelfs_remove_child(pi, n);
+ }
+ pohmelfs_name_free(parent, n);
+ err = 0;
+ }
+ mutex_unlock(&parent->offset_lock);
+
+ if (!err) {
+ psb->avail_size += inode->i_size;
+
+ pohmelfs_inode_del_inode(psb, pi);
+
+ mark_inode_dirty(dir);
+
+ inode->i_ctime = dir->i_ctime;
+ if (inode->i_nlink)
+ inode_dec_link_count(inode);
+ }
+ dprintk("%s: inode: %p, lock: %ld, unhashed: %d.\n",
+ __func__, pi, inode->i_state & I_LOCK, hlist_unhashed(&inode->i_hash));
+
+ return err;
+}
+
+/*
+ * Unlink and rmdir VFS callbacks.
+ */
+static int pohmelfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ return pohmelfs_remove_entry(dir, dentry);
+}
+
+static int pohmelfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ int err;
+ struct inode *inode = dentry->d_inode;
+
+ dprintk("%s: parent: %llu, inode: %llu, name: '%s', parent_nlink: %d, nlink: %d.\n",
+ __func__, POHMELFS_I(dir)->ino, POHMELFS_I(inode)->ino,
+ dentry->d_name.name, (signed)dir->i_nlink, (signed)inode->i_nlink);
+
+ err = pohmelfs_remove_entry(dir, dentry);
+ if (!err) {
+ inode_dec_link_count(dir);
+ inode_dec_link_count(inode);
+ }
+
+ return err;
+}
+
+/*
+ * Link creation is synchronous.
+ * I'm lazy.
+ * Earth is somewhat round.
+ */
+static int pohmelfs_create_link(struct pohmelfs_inode *parent, struct qstr *obj,
+ struct pohmelfs_inode *target, struct qstr *tstr)
+{
+ struct super_block *sb = parent->vfs_inode.i_sb;
+ struct pohmelfs_sb *psb = POHMELFS_SB(sb);
+ struct netfs_cmd *cmd;
+ struct netfs_trans *t;
+ void *data;
+ int err, parent_len, target_len = 0, cur_len, path_size = 0;
+
+ err = pohmelfs_data_lock(parent, 0, ~0, POHMELFS_WRITE_LOCK);
+ if (err)
+ return err;
+
+ err = sb->s_op->write_inode(&parent->vfs_inode, 0);
+ if (err)
+ goto err_out_exit;
+
+ if (tstr)
+ target_len = tstr->len;
+
+ parent_len = pohmelfs_path_length(parent);
+ if (target)
+ target_len += pohmelfs_path_length(target);
+
+ if (parent_len < 0) {
+ err = parent_len;
+ goto err_out_exit;
+ }
+
+ if (target_len < 0) {
+ err = target_len;
+ goto err_out_exit;
+ }
+
+ t = netfs_trans_alloc(psb, parent_len + target_len + obj->len + 2, 0, 0);
+ if (!t) {
+ err = -ENOMEM;
+ goto err_out_exit;
+ }
+ cur_len = netfs_trans_cur_len(t);
+
+ cmd = netfs_trans_current(t);
+ if (IS_ERR(cmd)) {
+ err = PTR_ERR(cmd);
+ goto err_out_free;
+ }
+
+ data = (void *)(cmd + 1);
+ cur_len -= sizeof(struct netfs_cmd);
+
+ err = pohmelfs_construct_path_string(parent, data, parent_len);
+ if (err > 0) {
+ /* Do not place null-byte before the slash */
+ path_size = err - 1;
+ cur_len -= path_size;
+
+ err = snprintf(data + path_size, cur_len, "/%s|", obj->name);
+
+ path_size += err;
+ cur_len -= err;
+
+ cmd->ext = path_size - 1; /* No | symbol */
+
+ if (target) {
+ err = pohmelfs_construct_path_string(target, data + path_size, target_len);
+ if (err > 0) {
+ path_size += err;
+ cur_len -= err;
+ }
+ }
+ }
+
+ if (err < 0)
+ goto err_out_free;
+
+ cmd->start = 0;
+
+ if (!target && tstr) {
+ if (tstr->len > cur_len - 1) {
+ err = -ENAMETOOLONG;
+ goto err_out_free;
+ }
+
+ err = snprintf(data + path_size, cur_len, "%s", tstr->name) + 1; /* 0-byte */
+ path_size += err;
+ cur_len -= err;
+ cmd->start = 1;
+ }
+
+ dprintk("%s: parent: %llu, obj: '%s', target_inode: %llu, target_str: '%s', full: '%s'.\n",
+ __func__, parent->ino, obj->name, (target)?target->ino:0, (tstr)?tstr->name:NULL,
+ (char *)data);
+
+ cmd->cmd = NETFS_LINK;
+ cmd->size = path_size;
+ cmd->id = parent->ino;
+
+ netfs_convert_cmd(cmd);
+
+ netfs_trans_update(cmd, t, path_size);
+
+ err = netfs_trans_finish(t, psb);
+ if (err)
+ goto err_out_exit;
+
+ return 0;
+
+err_out_free:
+ t->result = err;
+ netfs_trans_put(t);
+err_out_exit:
+ return err;
+}
+
+/*
+ * VFS hard and soft link callbacks.
+ */
+static int pohmelfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *dentry)
+{
+ struct inode *inode = old_dentry->d_inode;
+ struct pohmelfs_inode *pi = POHMELFS_I(inode);
+ int err;
+ struct qstr str = dentry->d_name;
+
+ str.hash = jhash(dentry->d_name.name, dentry->d_name.len, 0);
+
+ err = inode->i_sb->s_op->write_inode(inode, 0);
+ if (err)
+ return err;
+
+ err = pohmelfs_create_link(POHMELFS_I(dir), &str, pi, NULL);
+ if (err)
+ return err;
+
+ return pohmelfs_create_entry(dir, dentry, pi->ino, inode->i_mode);
+}
+
+static int pohmelfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+{
+ struct qstr sym_str;
+ struct qstr str = dentry->d_name;
+ struct inode *inode;
+ int err;
+
+ str.hash = jhash(dentry->d_name.name, dentry->d_name.len, 0);
+
+ sym_str.name = symname;
+ sym_str.len = strlen(symname);
+
+ err = pohmelfs_create_link(POHMELFS_I(dir), &str, NULL, &sym_str);
+ if (err)
+ goto err_out_exit;
+
+ err = pohmelfs_create_entry(dir, dentry, 0, S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO);
+ if (err)
+ goto err_out_exit;
+
+ inode = dentry->d_inode;
+
+ err = page_symlink(inode, symname, sym_str.len + 1);
+ if (err)
+ goto err_out_put;
+
+ return 0;
+
+err_out_put:
+ iput(inode);
+err_out_exit:
+ return err;
+}
+
+static int pohmelfs_send_rename(struct pohmelfs_inode *pi, struct pohmelfs_inode *parent,
+ struct qstr *str)
+{
+ int path_len, err, total_len = 0, inode_len, parent_len;
+ char *path;
+ struct netfs_trans *t;
+ struct netfs_cmd *cmd;
+ struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
+
+ parent_len = pohmelfs_path_length(parent);
+ inode_len = pohmelfs_path_length(pi);
+
+ if (parent_len < 0 || inode_len < 0)
+ return -EINVAL;
+
+ path_len = parent_len + inode_len + str->len + 3;
+
+ t = netfs_trans_alloc(psb, path_len, 0, 0);
+ if (!t)
+ return -ENOMEM;
+
+ cmd = netfs_trans_current(t);
+ path = (char *)(cmd + 1);
+
+ err = pohmelfs_construct_path_string(pi, path, inode_len);
+ if (err < 0)
+ goto err_out_unlock;
+
+ cmd->ext = err;
+
+ path += err;
+ total_len += err;
+ path_len -= err;
+
+ *path = '|';
+ path++;
+ total_len++;
+ path_len--;
+
+ err = pohmelfs_construct_path_string(parent, path, parent_len);
+ if (err < 0)
+ goto err_out_unlock;
+
+ /*
+ * Do not place a null-byte before the final slash and the name.
+ */
+ err--;
+ path += err;
+ total_len += err;
+ path_len -= err;
+
+ err = snprintf(path, path_len - 1, "/%s", str->name);
+
+ total_len += err + 1; /* 0 symbol */
+ path_len -= err + 1;
+
+ cmd->cmd = NETFS_RENAME;
+ cmd->id = pi->ino;
+ cmd->start = parent->ino;
+ cmd->size = total_len;
+
+ netfs_convert_cmd(cmd);
+
+ netfs_trans_update(cmd, t, total_len);
+
+ return netfs_trans_finish(t, psb);
+
+err_out_unlock:
+ netfs_trans_free(t);
+ return err;
+}
+
+static int pohmelfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ struct inode *inode = old_dentry->d_inode;
+ struct pohmelfs_inode *old_parent, *pi, *new_parent;
+ struct qstr str = new_dentry->d_name;
+ struct pohmelfs_name *n;
+ unsigned int old_hash;
+ int err = -ENOENT;
+
+ pi = POHMELFS_I(inode);
+ old_parent = POHMELFS_I(old_dir);
+
+ if (new_dir) {
+ new_dir->i_sb->s_op->write_inode(new_dir, 0);
+ }
+
+ old_hash = jhash(old_dentry->d_name.name, old_dentry->d_name.len, 0);
+ str.hash = jhash(new_dentry->d_name.name, new_dentry->d_name.len, 0);
+
+ str.len = new_dentry->d_name.len;
+ str.name = new_dentry->d_name.name;
+ str.hash = jhash(new_dentry->d_name.name, new_dentry->d_name.len, 0);
+
+ if (new_dir) {
+ new_parent = POHMELFS_I(new_dir);
+ err = -ENOTEMPTY;
+
+ if (S_ISDIR(inode->i_mode) &&
+ new_parent->total_len <= 3)
+ goto err_out_exit;
+ } else {
+ new_parent = old_parent;
+ }
+
+ dprintk("%s: ino: %llu, parent: %llu, name: '%s' -> parent: %llu, name: '%s', i_size: %llu.\n",
+ __func__, pi->ino, old_parent->ino, old_dentry->d_name.name,
+ new_parent->ino, new_dentry->d_name.name, inode->i_size);
+
+ if (test_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state) &&
+ test_bit(NETFS_INODE_OWNED, &pi->state)) {
+ err = pohmelfs_send_rename(pi, new_parent, &str);
+ if (err)
+ goto err_out_exit;
+ }
+
+ n = pohmelfs_name_alloc(str.len + 1);
+ if (!n)
+ goto err_out_exit;
+
+ mutex_lock(&new_parent->offset_lock);
+ n->ino = pi->ino;
+ n->mode = inode->i_mode;
+ n->len = str.len;
+ n->hash = str.hash;
+ sprintf(n->data, "%s", str.name);
+
+ err = pohmelfs_insert_name(new_parent, n);
+ mutex_unlock(&new_parent->offset_lock);
+
+ if (err)
+ goto err_out_exit;
+
+ mutex_lock(&old_parent->offset_lock);
+ n = pohmelfs_search_hash(old_parent, old_hash);
+ if (n)
+ pohmelfs_name_del(old_parent, n);
+ mutex_unlock(&old_parent->offset_lock);
+
+ mark_inode_dirty(inode);
+ mark_inode_dirty(&new_parent->vfs_inode);
+
+ WARN_ON_ONCE(list_empty(&inode->i_dentry));
+
+ return 0;
+
+err_out_exit:
+
+ clear_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
+
+ mutex_unlock(&inode->i_mutex);
+ return err;
+}
+
+/*
+ * POHMELFS directory inode operations.
+ */
+const struct inode_operations pohmelfs_dir_inode_ops = {
+ .link = pohmelfs_link,
+ .symlink = pohmelfs_symlink,
+ .unlink = pohmelfs_unlink,
+ .mkdir = pohmelfs_mkdir,
+ .rmdir = pohmelfs_rmdir,
+ .create = pohmelfs_create,
+ .lookup = pohmelfs_lookup,
+ .setattr = pohmelfs_setattr,
+ .rename = pohmelfs_rename,
+};
git.openpandora.org / pandora-kernel.git / commitdiff