diff options
Diffstat (limited to 'drivers/staging/pohmelfs/net.c')
| -rw-r--r-- | drivers/staging/pohmelfs/net.c | 1211 |
1 files changed, 1211 insertions, 0 deletions
diff --git a/drivers/staging/pohmelfs/net.c b/drivers/staging/pohmelfs/net.c new file mode 100644 index 000000000000..11ecac026ca7 --- /dev/null +++ b/drivers/staging/pohmelfs/net.c @@ -0,0 +1,1211 @@ +/* + * 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/fsnotify.h> +#include <linux/jhash.h> +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/kthread.h> +#include <linux/pagemap.h> +#include <linux/poll.h> +#include <linux/swap.h> +#include <linux/syscalls.h> +#include <linux/vmalloc.h> + +#include "netfs.h" + +/* + * Async machinery lives here. + * All commands being sent to server do _not_ require sync reply, + * instead, if it is really needed, like readdir or readpage, caller + * sleeps waiting for data, which will be placed into provided buffer + * and caller will be awakened. + * + * Every command response can come without some listener. For example + * readdir response will add new objects into cache without appropriate + * request from userspace. This is used in cache coherency. + * + * If object is not found for given data, it is discarded. + * + * All requests are received by dedicated kernel thread. + */ + +/* + * Basic network sending/receiving functions. + * Blocked mode is used. + */ +static int netfs_data_recv(struct netfs_state *st, void *buf, u64 size) +{ + struct msghdr msg; + struct kvec iov; + int err; + + BUG_ON(!size); + + iov.iov_base = buf; + iov.iov_len = size; + + msg.msg_iov = (struct iovec *)&iov; + msg.msg_iovlen = 1; + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_control = NULL; + msg.msg_controllen = 0; + msg.msg_flags = MSG_DONTWAIT; + + err = kernel_recvmsg(st->socket, &msg, &iov, 1, iov.iov_len, + msg.msg_flags); + if (err <= 0) { + printk("%s: failed to recv data: size: %llu, err: %d.\n", __func__, size, err); + if (err == 0) + err = -ECONNRESET; + } + + return err; +} + +static int pohmelfs_data_recv(struct netfs_state *st, void *data, unsigned int size) +{ + unsigned int revents = 0; + unsigned int err_mask = POLLERR | POLLHUP | POLLRDHUP; + unsigned int mask = err_mask | POLLIN; + int err = 0; + + while (size && !err) { + revents = netfs_state_poll(st); + + if (!(revents & mask)) { + DEFINE_WAIT(wait); + + for (;;) { + prepare_to_wait(&st->thread_wait, &wait, TASK_INTERRUPTIBLE); + if (kthread_should_stop()) + break; + + revents = netfs_state_poll(st); + + if (revents & mask) + break; + + if (signal_pending(current)) + break; + + schedule(); + continue; + } + finish_wait(&st->thread_wait, &wait); + } + + err = 0; + netfs_state_lock(st); + if (st->socket && (st->read_socket == st->socket) && (revents & POLLIN)) { + err = netfs_data_recv(st, data, size); + if (err > 0) { + data += err; + size -= err; + err = 0; + } else if (err == 0) + err = -ECONNRESET; + } + + if (revents & err_mask) { + printk("%s: revents: %x, socket: %p, size: %u, err: %d.\n", + __func__, revents, st->socket, size, err); + err = -ECONNRESET; + } + netfs_state_unlock(st); + + if (err < 0) { + if (netfs_state_trylock_send(st)) { + netfs_state_exit(st); + err = netfs_state_init(st); + if (!err) + err = -EAGAIN; + netfs_state_unlock_send(st); + } else { + st->need_reset = 1; + } + } + + if (kthread_should_stop()) + err = -ENODEV; + + if (err) + printk("%s: socket: %p, read_socket: %p, revents: %x, rev_error: %d, " + "should_stop: %d, size: %u, err: %d.\n", + __func__, st->socket, st->read_socket, + revents, revents & err_mask, kthread_should_stop(), size, err); + } + + return err; +} + +int pohmelfs_data_recv_and_check(struct netfs_state *st, void *data, unsigned int size) +{ + struct netfs_cmd *cmd = &st->cmd; + int err; + + err = pohmelfs_data_recv(st, data, size); + if (err) + return err; + + return pohmelfs_crypto_process_input_data(&st->eng, cmd->iv, data, NULL, size); +} + +/* + * Polling machinery. + */ + +struct netfs_poll_helper +{ + poll_table pt; + struct netfs_state *st; +}; + +static int netfs_queue_wake(wait_queue_t *wait, unsigned mode, int sync, void *key) +{ + struct netfs_state *st = container_of(wait, struct netfs_state, wait); + + wake_up(&st->thread_wait); + return 1; +} + +static void netfs_queue_func(struct file *file, wait_queue_head_t *whead, + poll_table *pt) +{ + struct netfs_state *st = container_of(pt, struct netfs_poll_helper, pt)->st; + + st->whead = whead; + init_waitqueue_func_entry(&st->wait, netfs_queue_wake); + add_wait_queue(whead, &st->wait); +} + +static void netfs_poll_exit(struct netfs_state *st) +{ + if (st->whead) { + remove_wait_queue(st->whead, &st->wait); + st->whead = NULL; + } +} + +static int netfs_poll_init(struct netfs_state *st) +{ + struct netfs_poll_helper ph; + + ph.st = st; + init_poll_funcptr(&ph.pt, &netfs_queue_func); + + st->socket->ops->poll(NULL, st->socket, &ph.pt); + return 0; +} + +/* + * Get response for readpage command. We search inode and page in its mapping + * and copy data into. If it was async request, then we queue page into shared + * data and wakeup listener, who will copy it to userspace. + * + * There is a work in progress of allowing to call copy_to_user() directly from + * async receiving kernel thread. + */ +static int pohmelfs_read_page_response(struct netfs_state *st) +{ + struct pohmelfs_sb *psb = st->psb; + struct netfs_cmd *cmd = &st->cmd; + struct inode *inode; + struct page *page; + int err = 0; + + if (cmd->size > PAGE_CACHE_SIZE) { + err = -EINVAL; + goto err_out_exit; + } + + inode = ilookup(st->psb->sb, cmd->id); + if (!inode) { + printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); + err = -ENOENT; + goto err_out_exit; + } + + page = find_get_page(inode->i_mapping, cmd->start >> PAGE_CACHE_SHIFT); + if (!page || !PageLocked(page)) { + printk("%s: failed to find/lock page: page: %p, id: %llu, start: %llu, index: %llu.\n", + __func__, page, cmd->id, cmd->start, cmd->start >> PAGE_CACHE_SHIFT); + + while (cmd->size) { + unsigned int sz = min(cmd->size, st->size); + + err = pohmelfs_data_recv(st, st->data, sz); + if (err) + break; + + cmd->size -= sz; + } + + err = -ENODEV; + if (page) + goto err_out_page_put; + goto err_out_put; + } + + if (cmd->size) { + void *addr; + + addr = kmap(page); + err = pohmelfs_data_recv(st, addr, cmd->size); + kunmap(page); + + if (err) + goto err_out_page_unlock; + } + + dprintk("%s: page: %p, start: %llu, size: %u, locked: %d.\n", + __func__, page, cmd->start, cmd->size, PageLocked(page)); + + SetPageChecked(page); + if ((psb->hash_string || psb->cipher_string) && psb->perform_crypto && cmd->size) { + err = pohmelfs_crypto_process_input_page(&st->eng, page, cmd->size, cmd->iv); + if (err < 0) + goto err_out_page_unlock; + } else { + SetPageUptodate(page); + unlock_page(page); + page_cache_release(page); + } + + pohmelfs_put_inode(POHMELFS_I(inode)); + wake_up(&st->psb->wait); + + return 0; + +err_out_page_unlock: + SetPageError(page); + unlock_page(page); +err_out_page_put: + page_cache_release(page); +err_out_put: + pohmelfs_put_inode(POHMELFS_I(inode)); +err_out_exit: + wake_up(&st->psb->wait); + return err; +} + +static int pohmelfs_check_name(struct pohmelfs_inode *parent, struct qstr *str, + struct netfs_inode_info *info) +{ + struct inode *inode; + struct pohmelfs_name *n; + int err = 0; + u64 ino = 0; + + mutex_lock(&parent->offset_lock); + n = pohmelfs_search_hash(parent, str->hash); + if (n) + ino = n->ino; + mutex_unlock(&parent->offset_lock); + + if (!ino) + goto out; + + inode = ilookup(parent->vfs_inode.i_sb, ino); + if (!inode) + goto out; + + dprintk("%s: parent: %llu, inode: %llu.\n", __func__, parent->ino, ino); + + pohmelfs_fill_inode(inode, info); + pohmelfs_put_inode(POHMELFS_I(inode)); + err = -EEXIST; +out: + return err; +} + +/* + * Readdir response from server. If special field is set, we wakeup + * listener (readdir() call), which will copy data to userspace. + */ +static int pohmelfs_readdir_response(struct netfs_state *st) +{ + struct inode *inode; + struct netfs_cmd *cmd = &st->cmd; + struct netfs_inode_info *info; + struct pohmelfs_inode *parent = NULL, *npi; + int err = 0, last = cmd->ext; + struct qstr str; + + if (cmd->size > st->size) + return -EINVAL; + + inode = ilookup(st->psb->sb, cmd->id); + if (!inode) { + printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); + return -ENOENT; + } + parent = POHMELFS_I(inode); + + if (!cmd->size && cmd->start) { + err = -cmd->start; + goto out; + } + + if (cmd->size) { + char *name; + + err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); + if (err) + goto err_out_put; + + info = (struct netfs_inode_info *)(st->data); + + name = (char *)(info + 1); + str.len = cmd->size - sizeof(struct netfs_inode_info) - 1 - cmd->cpad; + name[str.len] = 0; + str.name = name; + str.hash = jhash(str.name, str.len, 0); + + netfs_convert_inode_info(info); + + if (parent) { + err = pohmelfs_check_name(parent, &str, info); + if (err) { + if (err == -EEXIST) + err = 0; + goto out; + } + } + + info->ino = cmd->start; + if (!info->ino) + info->ino = pohmelfs_new_ino(st->psb); + + dprintk("%s: parent: %llu, ino: %llu, name: '%s', hash: %x, len: %u, mode: %o.\n", + __func__, parent->ino, info->ino, str.name, str.hash, str.len, + info->mode); + + npi = pohmelfs_new_inode(st->psb, parent, &str, info, 0); + if (IS_ERR(npi)) { + err = PTR_ERR(npi); + + if (err != -EEXIST) + goto err_out_put; + } else { + struct dentry *dentry, *alias, *pd; + + set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state); + clear_bit(NETFS_INODE_OWNED, &npi->state); + + pd = d_find_alias(&parent->vfs_inode); + if (pd) { + str.hash = full_name_hash(str.name, str.len); + dentry = d_alloc(pd, &str); + if (dentry) { + alias = d_materialise_unique(dentry, &npi->vfs_inode); + if (alias) + dput(dentry); + } + + dput(dentry); + dput(pd); + } + } + } +out: + if (last) { + set_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &parent->state); + set_bit(NETFS_INODE_REMOTE_SYNCED, &parent->state); + wake_up(&st->psb->wait); + } + pohmelfs_put_inode(parent); + + return err; + +err_out_put: + clear_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &parent->state); + printk("%s: parent: %llu, ino: %llu, cmd_id: %llu.\n", __func__, parent->ino, cmd->start, cmd->id); + pohmelfs_put_inode(parent); + wake_up(&st->psb->wait); + return err; +} + +/* + * Lookup command response. + * It searches for inode to be looked at (if it exists) and substitutes + * its inode information (size, permission, mode and so on), if inode does + * not exist, new one will be created and inserted into caches. + */ +static int pohmelfs_lookup_response(struct netfs_state *st) +{ + struct inode *inode = NULL; + struct netfs_cmd *cmd = &st->cmd; + struct netfs_inode_info *info; + struct pohmelfs_inode *parent = NULL, *npi; + int err = -EINVAL; + char *name; + + inode = ilookup(st->psb->sb, cmd->id); + if (!inode) { + printk("%s: lookup response: id: %llu, start: %llu, size: %u.\n", + __func__, cmd->id, cmd->start, cmd->size); + err = -ENOENT; + goto err_out_exit; + } + parent = POHMELFS_I(inode); + + if (!cmd->size) { + err = -cmd->start; + goto err_out_put; + } + + if (cmd->size < sizeof(struct netfs_inode_info)) { + printk("%s: broken lookup response: id: %llu, start: %llu, size: %u.\n", + __func__, cmd->id, cmd->start, cmd->size); + err = -EINVAL; + goto err_out_put; + } + + err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); + if (err) + goto err_out_put; + + info = (struct netfs_inode_info *)(st->data); + name = (char *)(info + 1); + + netfs_convert_inode_info(info); + + info->ino = cmd->start; + if (!info->ino) + info->ino = pohmelfs_new_ino(st->psb); + + dprintk("%s: parent: %llu, ino: %llu, name: '%s', start: %llu.\n", + __func__, parent->ino, info->ino, name, cmd->start); + + if (cmd->start) + npi = pohmelfs_new_inode(st->psb, parent, NULL, info, 0); + else { + struct qstr str; + + str.name = name; + str.len = cmd->size - sizeof(struct netfs_inode_info) - 1 - cmd->cpad; + str.hash = jhash(name, str.len, 0); + + npi = pohmelfs_new_inode(st->psb, parent, &str, info, 0); + } + if (IS_ERR(npi)) { + err = PTR_ERR(npi); + + if (err != -EEXIST) + goto err_out_put; + } else { + set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state); + clear_bit(NETFS_INODE_OWNED, &npi->state); + } + + clear_bit(NETFS_COMMAND_PENDING, &parent->state); + pohmelfs_put_inode(parent); + + wake_up(&st->psb->wait); + + return 0; + +err_out_put: + pohmelfs_put_inode(parent); +err_out_exit: + clear_bit(NETFS_COMMAND_PENDING, &parent->state); + wake_up(&st->psb->wait); + printk("%s: inode: %p, id: %llu, start: %llu, size: %u, err: %d.\n", + __func__, inode, cmd->id, cmd->start, cmd->size, err); + return err; +} + +/* + * Create response, just marks local inode as 'created', so that writeback + * for any of its children (or own) would not try to sync it again. + */ +static int pohmelfs_create_response(struct netfs_state *st) +{ + struct inode *inode; + struct netfs_cmd *cmd = &st->cmd; + struct pohmelfs_inode *pi; + + inode = ilookup(st->psb->sb, cmd->id); + if (!inode) { + printk("%s: failed to find inode: id: %llu, start: %llu.\n", + __func__, cmd->id, cmd->start); + goto err_out_exit; + } + + pi = POHMELFS_I(inode); + + /* + * To lock or not to lock? + * We actually do not care if it races... + */ + if (cmd->start) + make_bad_inode(inode); + set_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state); + + pohmelfs_put_inode(pi); + + wake_up(&st->psb->wait); + return 0; + +err_out_exit: + wake_up(&st->psb->wait); + return -ENOENT; +} + +/* + * Object remove response. Just says that remove request has been received. + * Used in cache coherency protocol. + */ +static int pohmelfs_remove_response(struct netfs_state *st) +{ + struct netfs_cmd *cmd = &st->cmd; + int err; + + err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); + if (err) + return err; + + dprintk("%s: parent: %llu, path: '%s'.\n", __func__, cmd->id, (char *)st->data); + + return 0; +} + +/* + * Transaction reply processing. + * + * Find transaction based on its generation number, bump its reference counter, + * so that none could free it under us, drop from the trees and lists and + * drop reference counter. When it hits zero (when all destinations replied + * and all timeout handled by async scanning code), completion will be called + * and transaction will be freed. + */ +static int pohmelfs_transaction_response(struct netfs_state *st) +{ + struct netfs_trans_dst *dst; + struct netfs_trans *t = NULL; + struct netfs_cmd *cmd = &st->cmd; + short err = (signed)cmd->ext; + + mutex_lock(&st->trans_lock); + dst = netfs_trans_search(st, cmd->start); + if (dst) { + netfs_trans_remove_nolock(dst, st); + t = dst->trans; + } + mutex_unlock(&st->trans_lock); + + if (!t) { + printk("%s: failed to find transaction: start: %llu: id: %llu, size: %u, ext: %u.\n", + __func__, cmd->start, cmd->id, cmd->size, cmd->ext); + err = -EINVAL; + goto out; + } + + t->result = err; + netfs_trans_drop_dst_nostate(dst); + +out: + wake_up(&st->psb->wait); + return err; +} + +/* + * Inode metadata cache coherency message. + */ +static int pohmelfs_page_cache_response(struct netfs_state *st) +{ + struct netfs_cmd *cmd = &st->cmd; + struct inode *inode; + + dprintk("%s: st: %p, id: %llu, start: %llu, size: %u.\n", __func__, st, cmd->id, cmd->start, cmd->size); + + inode = ilookup(st->psb->sb, cmd->id); + if (!inode) { + printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); + return -ENOENT; + } + + set_bit(NETFS_INODE_NEED_FLUSH, &POHMELFS_I(inode)->state); + pohmelfs_put_inode(POHMELFS_I(inode)); + + return 0; +} + +/* + * Root capabilities response: export statistics + * like used and available size, number of files and dirs, + * permissions. + */ +static int pohmelfs_root_cap_response(struct netfs_state *st) +{ + struct netfs_cmd *cmd = &st->cmd; + struct netfs_root_capabilities *cap; + struct pohmelfs_sb *psb = st->psb; + + if (cmd->size != sizeof(struct netfs_root_capabilities)) { + psb->flags = EPROTO; + wake_up(&psb->wait); + return -EPROTO; + } + + cap = st->data; + + netfs_convert_root_capabilities(cap); + + if (psb->total_size < cap->used + cap->avail) + psb->total_size = cap->used + cap->avail; + if (cap->avail) + psb->avail_size = cap->avail; + psb->state_flags = cap->flags; + + if (psb->state_flags & POHMELFS_FLAGS_RO) { + psb->sb->s_flags |= MS_RDONLY; + printk(KERN_INFO "Mounting POHMELFS (%d) read-only.\n", psb->idx); + } + + if (psb->state_flags & POHMELFS_FLAGS_XATTR) + printk(KERN_INFO "Mounting POHMELFS (%d) " + "with extended attributes support.\n", psb->idx); + + if (atomic_read(&psb->total_inodes) <= 1) + atomic_long_set(&psb->total_inodes, cap->nr_files); + + dprintk("%s: total: %llu, avail: %llu, flags: %llx, inodes: %llu.\n", + __func__, psb->total_size, psb->avail_size, psb->state_flags, cap->nr_files); + + psb->flags = 0; + wake_up(&psb->wait); + return 0; +} + +/* + * Crypto capabilities of the server, where it says that + * it supports or does not requested hash/cipher algorithms. + */ +static int pohmelfs_crypto_cap_response(struct netfs_state *st) +{ + struct netfs_cmd *cmd = &st->cmd; + struct netfs_crypto_capabilities *cap; + struct pohmelfs_sb *psb = st->psb; + int err = 0; + + if (cmd->size != sizeof(struct netfs_crypto_capabilities)) { + psb->flags = EPROTO; + wake_up(&psb->wait); + return -EPROTO; + } + + cap = st->data; + + dprintk("%s: cipher '%s': %s, hash: '%s': %s.\n", + __func__, + psb->cipher_string, (cap->cipher_strlen)?"SUPPORTED":"NOT SUPPORTED", + psb->hash_string, (cap->hash_strlen)?"SUPPORTED":"NOT SUPPORTED"); + + if (!cap->hash_strlen) { + if (psb->hash_strlen && psb->crypto_fail_unsupported) + err = -ENOTSUPP; + psb->hash_strlen = 0; + kfree(psb->hash_string); + psb->hash_string = NULL; + } + + if (!cap->cipher_strlen) { + if (psb->cipher_strlen && psb->crypto_fail_unsupported) + err = -ENOTSUPP; + psb->cipher_strlen = 0; + kfree(psb->cipher_string); + psb->cipher_string = NULL; + } + + return err; +} + +/* + * Capabilities handshake response. + */ +static int pohmelfs_capabilities_response(struct netfs_state *st) +{ + struct netfs_cmd *cmd = &st->cmd; + int err = 0; + + err = pohmelfs_data_recv(st, st->data, cmd->size); + if (err) + return err; + + switch (cmd->id) { + case POHMELFS_CRYPTO_CAPABILITIES: + return pohmelfs_crypto_cap_response(st); + case POHMELFS_ROOT_CAPABILITIES: + return pohmelfs_root_cap_response(st); + default: + break; + } + return -EINVAL; +} + +/* + * Receiving extended attribute. + * Does not work properly if received size is more than requested one, + * it should not happen with current request/reply model though. + */ +static int pohmelfs_getxattr_response(struct netfs_state *st) +{ + struct pohmelfs_sb *psb = st->psb; + struct netfs_cmd *cmd = &st->cmd; + struct pohmelfs_mcache *m; + short error = (signed short)cmd->ext, err; + unsigned int sz, total_size; + + m = pohmelfs_mcache_search(psb, cmd->id); + + dprintk("%s: id: %llu, gen: %llu, err: %d.\n", + __func__, cmd->id, (m)?m->gen:0, error); + + if (!m) { + printk("%s: failed to find getxattr cache entry: id: %llu.\n", __func__, cmd->id); + return -ENOENT; + } + + if (cmd->size) { + sz = min_t(unsigned int, cmd->size, m->size); + err = pohmelfs_data_recv_and_check(st, m->data, sz); + if (err) { + error = err; + goto out; + } + + m->size = sz; + total_size = cmd->size - sz; + + while (total_size) { + sz = min(total_size, st->size); + + err = pohmelfs_data_recv_and_check(st, st->data, sz); + if (err) { + error = err; + break; + } + + total_size -= sz; + } + } + +out: + m->err = error; + complete(&m->complete); + pohmelfs_mcache_put(psb, m); + + return error; +} + +int pohmelfs_data_lock_response(struct netfs_state *st) +{ + struct pohmelfs_sb *psb = st->psb; + struct netfs_cmd *cmd = &st->cmd; + struct pohmelfs_mcache *m; + short err = (signed short)cmd->ext; + u64 id = cmd->id; + + m = pohmelfs_mcache_search(psb, id); + + dprintk("%s: id: %llu, gen: %llu, err: %d.\n", + __func__, cmd->id, (m)?m->gen:0, err); + + if (!m) { + pohmelfs_data_recv(st, st->data, cmd->size); + printk("%s: failed to find data lock response: id: %llu.\n", __func__, cmd->id); + return -ENOENT; + } + + if (cmd->size) + err = pohmelfs_data_recv_and_check(st, &m->info, cmd->size); + + m->err = err; + complete(&m->complete); + pohmelfs_mcache_put(psb, m); + + return err; +} + +static void __inline__ netfs_state_reset(struct netfs_state *st) +{ + netfs_state_lock_send(st); + netfs_state_exit(st); + netfs_state_init(st); + netfs_state_unlock_send(st); +} + +/* + * Main receiving function, called from dedicated kernel thread. + */ +static int pohmelfs_recv(void *data) +{ + int err = -EINTR; + struct netfs_state *st = data; + struct netfs_cmd *cmd = &st->cmd; + + while (!kthread_should_stop()) { + /* + * If socket will be reset after this statement, then + * pohmelfs_data_recv() will just fail and loop will + * start again, so it can be done without any locks. + * + * st->read_socket is needed to prevents state machine + * breaking between this data reading and subsequent one + * in protocol specific functions during connection reset. + * In case of reset we have to read next command and do + * not expect data for old command to magically appear in + * new connection. + */ + st->read_socket = st->socket; + err = pohmelfs_data_recv(st, cmd, sizeof(struct netfs_cmd)); + if (err) { + msleep(1000); + continue; + } + + netfs_convert_cmd(cmd); + + dprintk("%s: cmd: %u, id: %llu, start: %llu, size: %u, " + "ext: %u, csize: %u, cpad: %u.\n", + __func__, cmd->cmd, cmd->id, cmd->start, + cmd->size, cmd->ext, cmd->csize, cmd->cpad); + + if (cmd->csize) { + struct pohmelfs_crypto_engine *e = &st->eng; + + if (unlikely(cmd->csize > e->size/2)) { + netfs_state_reset(st); + continue; + } + + if (e->hash && unlikely(cmd->csize != st->psb->crypto_attached_size)) { + dprintk("%s: cmd: cmd: %u, id: %llu, start: %llu, size: %u, " + "csize: %u != digest size %u.\n", + __func__, cmd->cmd, cmd->id, cmd->start, cmd->size, + cmd->csize, st->psb->crypto_attached_size); + netfs_state_reset(st); + continue; + } + + err = pohmelfs_data_recv(st, e->data, cmd->csize); + if (err) { + netfs_state_reset(st); + continue; + } + +#ifdef CONFIG_POHMELFS_DEBUG + { + unsigned int i; + unsigned char *hash = e->data; + + dprintk("%s: received hash: ", __func__); + for (i=0; i<cmd->csize; ++i) { + printk("%02x ", hash[i]); + } + printk("\n"); + } +#endif + cmd->size -= cmd->csize; + } + + /* + * This should catch protocol breakage and random garbage instead of commands. + */ + if (unlikely((cmd->size > st->size) && (cmd->cmd != NETFS_XATTR_GET))) { + netfs_state_reset(st); + continue; + } + + switch (cmd->cmd) { + case NETFS_READ_PAGE: + err = pohmelfs_read_page_response(st); + break; + case NETFS_READDIR: + err = pohmelfs_readdir_response(st); + break; + case NETFS_LOOKUP: + err = pohmelfs_lookup_response(st); + break; + case NETFS_CREATE: + err = pohmelfs_create_response(st); + break; + case NETFS_REMOVE: + err = pohmelfs_remove_response(st); + break; + case NETFS_TRANS: + err = pohmelfs_transaction_response(st); + break; + case NETFS_PAGE_CACHE: + err = pohmelfs_page_cache_response(st); + break; + case NETFS_CAPABILITIES: + err = pohmelfs_capabilities_response(st); + break; + case NETFS_LOCK: + err = pohmelfs_data_lock_response(st); + break; + case NETFS_XATTR_GET: + err = pohmelfs_getxattr_response(st); + break; + default: + printk("%s: wrong cmd: %u, id: %llu, start: %llu, size: %u, ext: %u.\n", + __func__, cmd->cmd, cmd->id, cmd->start, cmd->size, cmd->ext); + netfs_state_reset(st); + break; + } + } + + while (!kthread_should_stop()) + schedule_timeout_uninterruptible(msecs_to_jiffies(10)); + + return err; +} + +int netfs_state_init(struct netfs_state *st) +{ + int err; + struct pohmelfs_ctl *ctl = &st->ctl; + + err = sock_create(ctl->addr.sa_family, ctl->type, ctl->proto, &st->socket); + if (err) { + printk("%s: failed to create a socket: family: %d, type: %d, proto: %d, err: %d.\n", + __func__, ctl->addr.sa_family, ctl->type, ctl->proto, err); + goto err_out_exit; + } + + st->socket->sk->sk_allocation = GFP_NOIO; + st->socket->sk->sk_sndtimeo = st->socket->sk->sk_rcvtimeo = msecs_to_jiffies(60000); + + err = kernel_connect(st->socket, (struct sockaddr *)&ctl->addr, ctl->addrlen, 0); + if (err) { + printk("%s: failed to connect to server: idx: %u, err: %d.\n", + __func__, st->psb->idx, err); + goto err_out_release; + } + st->socket->sk->sk_sndtimeo = st->socket->sk->sk_rcvtimeo = msecs_to_jiffies(60000); + + err = netfs_poll_init(st); + if (err) + goto err_out_release; + + if (st->socket->ops->family == AF_INET) { + struct sockaddr_in *sin = (struct sockaddr_in *)&ctl->addr; + printk(KERN_INFO "%s: (re)connected to peer %u.%u.%u.%u:%d.\n", __func__, + NIPQUAD(sin->sin_addr.s_addr), ntohs(sin->sin_port)); + } else if (st->socket->ops->family == AF_INET6) { + struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&ctl->addr; + printk(KERN_INFO "%s: (re)connected to peer " + "%pi6:%d", + __func__, &sin->sin6_addr, ntohs(sin->sin6_port)); + } + + return 0; + +err_out_release: + sock_release(st->socket); +err_out_exit: + st->socket = NULL; + return err; +} + +void netfs_state_exit(struct netfs_state *st) +{ + if (st->socket) { + netfs_poll_exit(st); + st->socket->ops->shutdown(st->socket, 2); + + if (st->socket->ops->family == AF_INET) { + struct sockaddr_in *sin = (struct sockaddr_in *)&st->ctl.addr; + printk("%s: disconnected from peer %u.%u.%u.%u:%d.\n", __func__, + NIPQUAD(sin->sin_addr.s_addr), ntohs(sin->sin_port)); + } else if (st->socket->ops->family == AF_INET6) { + struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&st->ctl.addr; + printk("%s: disconnected from peer " + "%pi6:%d", + __func__, &sin->sin6_addr, ntohs(sin->sin6_port)); + } + + sock_release(st->socket); + st->socket = NULL; + st->read_socket = NULL; + st->need_reset = 0; + } +} + +int pohmelfs_state_init_one(struct pohmelfs_sb *psb, struct pohmelfs_config *conf) +{ + struct netfs_state *st = &conf->state; + int err = -ENOMEM; + + mutex_init(&st->__state_lock); + mutex_init(&st->__state_send_lock); + init_waitqueue_head(&st->thread_wait); + + st->psb = psb; + st->trans_root = RB_ROOT; + mutex_init(&st->trans_lock); + + st->size = psb->trans_data_size; + st->data = kmalloc(st->size, GFP_KERNEL); + if (!st->data) + goto err_out_exit; + + if (psb->perform_crypto) { + err = pohmelfs_crypto_engine_init(&st->eng, psb); + if (err) + goto err_out_free_data; + } + + err = netfs_state_init(st); + if (err) + goto err_out_free_engine; + + st->thread = kthread_run(pohmelfs_recv, st, "pohmelfs/%u", psb->idx); + if (IS_ERR(st->thread)) { + err = PTR_ERR(st->thread); + goto err_out_netfs_exit; + } + + if (!psb->active_state) + psb->active_state = conf; + + dprintk("%s: conf: %p, st: %p, socket: %p.\n", + __func__, conf, st, st->socket); + return 0; + +err_out_netfs_exit: + netfs_state_exit(st); +err_out_free_engine: + pohmelfs_crypto_engine_exit(&st->eng); +err_out_free_data: + kfree(st->data); +err_out_exit: + return err; + +} + +void pohmelfs_state_flush_transactions(struct netfs_state *st) +{ + struct rb_node *rb_node; + struct netfs_trans_dst *dst; + + mutex_lock(&st->trans_lock); + for (rb_node = rb_first(&st->trans_root); rb_node; ) { + dst = rb_entry(rb_node, struct netfs_trans_dst, state_entry); + rb_node = rb_next(rb_node); + + dst->trans->result = -EINVAL; + netfs_trans_remove_nolock(dst, st); + netfs_trans_drop_dst_nostate(dst); + } + mutex_unlock(&st->trans_lock); +} + +static void pohmelfs_state_exit_one(struct pohmelfs_config *c) +{ + struct netfs_state *st = &c->state; + + dprintk("%s: exiting, st: %p.\n", __func__, st); + if (st->thread) { + kthread_stop(st->thread); + st->thread = NULL; + } + + netfs_state_lock_send(st); + netfs_state_exit(st); + netfs_state_unlock_send(st); + + pohmelfs_state_flush_transactions(st); + + pohmelfs_crypto_engine_exit(&st->eng); + kfree(st->data); + + kfree(c); +} + +/* + * Initialize network stack. It searches for given ID in global + * configuration table, this contains information of the remote server + * (address (any supported by socket interface) and port, protocol and so on). + */ +int pohmelfs_state_init(struct pohmelfs_sb *psb) +{ + int err = -ENOMEM; + + err = pohmelfs_copy_config(psb); + if (err) { + pohmelfs_state_exit(psb); + return err; + } + + return 0; +} + +void pohmelfs_state_exit(struct pohmelfs_sb *psb) +{ + struct pohmelfs_config *c, *tmp; + + list_for_each_entry_safe(c, tmp, &psb->state_list, config_entry) { + list_del(&c->config_entry); + pohmelfs_state_exit_one(c); + } +} + +void pohmelfs_switch_active(struct pohmelfs_sb *psb) +{ + struct pohmelfs_config *c = psb->active_state; + + if (!list_empty(&psb->state_list)) { + if (c->config_entry.next != &psb->state_list) { + psb->active_state = list_entry(c->config_entry.next, + struct pohmelfs_config, config_entry); + } else { + psb->active_state = list_entry(psb->state_list.next, + struct pohmelfs_config, config_entry); + } + + dprintk("%s: empty: %d, active %p -> %p.\n", + __func__, list_empty(&psb->state_list), c, + psb->active_state); + } else + psb->active_state = NULL; +} + +void pohmelfs_check_states(struct pohmelfs_sb *psb) +{ + struct pohmelfs_config *c, *tmp; + LIST_HEAD(delete_list); + + mutex_lock(&psb->state_lock); + list_for_each_entry_safe(c, tmp, &psb->state_list, config_entry) { + if (pohmelfs_config_check(c, psb->idx)) { + + if (psb->active_state == c) + pohmelfs_switch_active(psb); + list_move(&c->config_entry, &delete_list); + } + } + pohmelfs_copy_config(psb); + mutex_unlock(&psb->state_lock); + + list_for_each_entry_safe(c, tmp, &delete_list, config_entry) { + list_del(&c->config_entry); + pohmelfs_state_exit_one(c); + } +} |