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|
/*
* 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);
}
}
|