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path: root/drivers/staging/dst/state.c
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Diffstat (limited to 'drivers/staging/dst/state.c')
-rw-r--r--drivers/staging/dst/state.c844
1 files changed, 0 insertions, 844 deletions
diff --git a/drivers/staging/dst/state.c b/drivers/staging/dst/state.c
deleted file mode 100644
index 02a05e6c48c..00000000000
--- a/drivers/staging/dst/state.c
+++ /dev/null
@@ -1,844 +0,0 @@
-/*
- * 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/buffer_head.h>
-#include <linux/blkdev.h>
-#include <linux/bio.h>
-#include <linux/connector.h>
-#include <linux/dst.h>
-#include <linux/device.h>
-#include <linux/in.h>
-#include <linux/in6.h>
-#include <linux/socket.h>
-#include <linux/slab.h>
-
-#include <net/sock.h>
-
-/*
- * Polling machinery.
- */
-
-struct dst_poll_helper {
- poll_table pt;
- struct dst_state *st;
-};
-
-static int dst_queue_wake(wait_queue_t *wait, unsigned mode,
- int sync, void *key)
-{
- struct dst_state *st = container_of(wait, struct dst_state, wait);
-
- wake_up(&st->thread_wait);
- return 1;
-}
-
-static void dst_queue_func(struct file *file, wait_queue_head_t *whead,
- poll_table *pt)
-{
- struct dst_state *st = container_of(pt, struct dst_poll_helper, pt)->st;
-
- st->whead = whead;
- init_waitqueue_func_entry(&st->wait, dst_queue_wake);
- add_wait_queue(whead, &st->wait);
-}
-
-void dst_poll_exit(struct dst_state *st)
-{
- if (st->whead) {
- remove_wait_queue(st->whead, &st->wait);
- st->whead = NULL;
- }
-}
-
-int dst_poll_init(struct dst_state *st)
-{
- struct dst_poll_helper ph;
-
- ph.st = st;
- init_poll_funcptr(&ph.pt, &dst_queue_func);
-
- st->socket->ops->poll(NULL, st->socket, &ph.pt);
- return 0;
-}
-
-/*
- * Header receiving function - may block.
- */
-static int dst_data_recv_header(struct socket *sock,
- void *data, unsigned int size, int block)
-{
- struct msghdr msg;
- struct kvec iov;
- int err;
-
- iov.iov_base = data;
- 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 = (block) ? MSG_WAITALL : MSG_DONTWAIT;
-
- err = kernel_recvmsg(sock, &msg, &iov, 1, iov.iov_len,
- msg.msg_flags);
- if (err != size)
- return -1;
-
- return 0;
-}
-
-/*
- * Header sending function - may block.
- */
-int dst_data_send_header(struct socket *sock,
- void *data, unsigned int size, int more)
-{
- struct msghdr msg;
- struct kvec iov;
- int err;
-
- iov.iov_base = data;
- 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_WAITALL | (more ? MSG_MORE : 0);
-
- err = kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
- if (err != size) {
- dprintk("%s: size: %u, more: %d, err: %d.\n",
- __func__, size, more, err);
- return -1;
- }
-
- return 0;
-}
-
-/*
- * Block autoconfiguration: request size of the storage and permissions.
- */
-static int dst_request_remote_config(struct dst_state *st)
-{
- struct dst_node *n = st->node;
- int err = -EINVAL;
- struct dst_cmd *cmd = st->data;
-
- memset(cmd, 0, sizeof(struct dst_cmd));
- cmd->cmd = DST_CFG;
-
- dst_convert_cmd(cmd);
-
- err = dst_data_send_header(st->socket, cmd, sizeof(struct dst_cmd), 0);
- if (err)
- goto out;
-
- err = dst_data_recv_header(st->socket, cmd, sizeof(struct dst_cmd), 1);
- if (err)
- goto out;
-
- dst_convert_cmd(cmd);
-
- if (cmd->cmd != DST_CFG) {
- err = -EINVAL;
- dprintk("%s: checking result: cmd: %d, size reported: %llu.\n",
- __func__, cmd->cmd, cmd->sector);
- goto out;
- }
-
- if (n->size != 0)
- n->size = min_t(loff_t, n->size, cmd->sector);
- else
- n->size = cmd->sector;
-
- n->info->size = n->size;
- st->permissions = cmd->rw;
-
-out:
- dprintk("%s: n: %p, err: %d, size: %llu, permission: %x.\n",
- __func__, n, err, n->size, st->permissions);
- return err;
-}
-
-/*
- * Socket machinery.
- */
-
-#define DST_DEFAULT_TIMEO 20000
-
-int dst_state_socket_create(struct dst_state *st)
-{
- int err;
- struct socket *sock;
- struct dst_network_ctl *ctl = &st->ctl;
-
- err = sock_create(ctl->addr.sa_family, ctl->type, ctl->proto, &sock);
- if (err < 0)
- return err;
-
- sock->sk->sk_sndtimeo = sock->sk->sk_rcvtimeo =
- msecs_to_jiffies(DST_DEFAULT_TIMEO);
- sock->sk->sk_allocation = GFP_NOIO;
-
- st->socket = st->read_socket = sock;
- return 0;
-}
-
-void dst_state_socket_release(struct dst_state *st)
-{
- dprintk("%s: st: %p, socket: %p, n: %p.\n",
- __func__, st, st->socket, st->node);
- if (st->socket) {
- sock_release(st->socket);
- st->socket = NULL;
- st->read_socket = NULL;
- }
-}
-
-void dst_dump_addr(struct socket *sk, struct sockaddr *sa, char *str)
-{
- if (sk->ops->family == AF_INET) {
- struct sockaddr_in *sin = (struct sockaddr_in *)sa;
- printk(KERN_INFO "%s %u.%u.%u.%u:%d.\n", str,
- NIPQUAD(sin->sin_addr.s_addr), ntohs(sin->sin_port));
- } else if (sk->ops->family == AF_INET6) {
- struct sockaddr_in6 *sin = (struct sockaddr_in6 *)sa;
- printk(KERN_INFO "%s %pi6:%d",
- str, &sin->sin6_addr, ntohs(sin->sin6_port));
- }
-}
-
-void dst_state_exit_connected(struct dst_state *st)
-{
- if (st->socket) {
- dst_poll_exit(st);
- st->socket->ops->shutdown(st->socket, 2);
-
- dst_dump_addr(st->socket, (struct sockaddr *)&st->ctl.addr,
- "Disconnected peer");
- dst_state_socket_release(st);
- }
-}
-
-static int dst_state_init_connected(struct dst_state *st)
-{
- int err;
- struct dst_network_ctl *ctl = &st->ctl;
-
- err = dst_state_socket_create(st);
- if (err)
- goto err_out_exit;
-
- err = kernel_connect(st->socket, (struct sockaddr *)&st->ctl.addr,
- st->ctl.addr.sa_data_len, 0);
- if (err)
- goto err_out_release;
-
- err = dst_poll_init(st);
- if (err)
- goto err_out_release;
-
- dst_dump_addr(st->socket, (struct sockaddr *)&ctl->addr,
- "Connected to peer");
-
- return 0;
-
-err_out_release:
- dst_state_socket_release(st);
-err_out_exit:
- return err;
-}
-
-/*
- * State reset is used to reconnect to the remote peer.
- * May fail, but who cares, we will try again later.
- */
-static inline void dst_state_reset_nolock(struct dst_state *st)
-{
- dst_state_exit_connected(st);
- dst_state_init_connected(st);
-}
-
-static inline void dst_state_reset(struct dst_state *st)
-{
- dst_state_lock(st);
- dst_state_reset_nolock(st);
- dst_state_unlock(st);
-}
-
-/*
- * Basic network sending/receiving functions.
- * Blocked mode is used.
- */
-static int dst_data_recv_raw(struct dst_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) {
- dprintk("%s: failed to recv data: size: %llu, err: %d.\n",
- __func__, size, err);
- if (err == 0)
- err = -ECONNRESET;
-
- dst_state_exit_connected(st);
- }
-
- return err;
-}
-
-/*
- * Ping command to early detect failed nodes.
- */
-static int dst_send_ping(struct dst_state *st)
-{
- struct dst_cmd *cmd = st->data;
- int err = -ECONNRESET;
-
- dst_state_lock(st);
- if (st->socket) {
- memset(cmd, 0, sizeof(struct dst_cmd));
-
- cmd->cmd = __cpu_to_be32(DST_PING);
-
- err = dst_data_send_header(st->socket, cmd,
- sizeof(struct dst_cmd), 0);
- }
- dprintk("%s: st: %p, socket: %p, err: %d.\n", __func__,
- st, st->socket, err);
- dst_state_unlock(st);
-
- return err;
-}
-
-/*
- * Receiving function, which should either return error or read
- * whole block request. If there was no traffic for a one second,
- * send a ping, since remote node may die.
- */
-int dst_data_recv(struct dst_state *st, void *data, unsigned int size)
-{
- unsigned int revents = 0;
- unsigned int err_mask = POLLERR | POLLHUP | POLLRDHUP;
- unsigned int mask = err_mask | POLLIN;
- struct dst_node *n = st->node;
- int err = 0;
-
- while (size && !err) {
- revents = dst_state_poll(st);
-
- if (!(revents & mask)) {
- DEFINE_WAIT(wait);
-
- for (;;) {
- prepare_to_wait(&st->thread_wait, &wait,
- TASK_INTERRUPTIBLE);
- if (!n->trans_scan_timeout || st->need_exit)
- break;
-
- revents = dst_state_poll(st);
-
- if (revents & mask)
- break;
-
- if (signal_pending(current))
- break;
-
- if (!schedule_timeout(HZ)) {
- err = dst_send_ping(st);
- if (err)
- return err;
- }
-
- continue;
- }
- finish_wait(&st->thread_wait, &wait);
- }
-
- err = -ECONNRESET;
- dst_state_lock(st);
-
- if (st->socket && (st->read_socket == st->socket) &&
- (revents & POLLIN)) {
- err = dst_data_recv_raw(st, data, size);
- if (err > 0) {
- data += err;
- size -= err;
- err = 0;
- }
- }
-
- if (revents & err_mask || !st->socket) {
- dprintk("%s: revents: %x, socket: %p, size: %u, "
- "err: %d.\n", __func__, revents,
- st->socket, size, err);
- err = -ECONNRESET;
- }
-
- dst_state_unlock(st);
-
- if (!n->trans_scan_timeout)
- err = -ENODEV;
- }
-
- return err;
-}
-
-/*
- * Send block autoconf reply.
- */
-static int dst_process_cfg(struct dst_state *st)
-{
- struct dst_node *n = st->node;
- struct dst_cmd *cmd = st->data;
- int err;
-
- cmd->sector = n->size;
- cmd->rw = st->permissions;
-
- dst_convert_cmd(cmd);
-
- dst_state_lock(st);
- err = dst_data_send_header(st->socket, cmd, sizeof(struct dst_cmd), 0);
- dst_state_unlock(st);
-
- return err;
-}
-
-/*
- * Receive block IO from the network.
- */
-static int dst_recv_bio(struct dst_state *st, struct bio *bio,
- unsigned int total_size)
-{
- struct bio_vec *bv;
- int i, err;
- void *data;
- unsigned int sz;
-
- bio_for_each_segment(bv, bio, i) {
- sz = min(total_size, bv->bv_len);
-
- dprintk("%s: bio: %llu/%u, total: %u, len: %u, sz: %u, "
- "off: %u.\n", __func__, (u64)bio->bi_sector,
- bio->bi_size, total_size, bv->bv_len, sz,
- bv->bv_offset);
-
- data = kmap(bv->bv_page) + bv->bv_offset;
- err = dst_data_recv(st, data, sz);
- kunmap(bv->bv_page);
-
- bv->bv_len = sz;
-
- if (err)
- return err;
-
- total_size -= sz;
- if (total_size == 0)
- break;
- }
-
- return 0;
-}
-
-/*
- * Our block IO has just completed and arrived: get it.
- */
-static int dst_process_io_response(struct dst_state *st)
-{
- struct dst_node *n = st->node;
- struct dst_cmd *cmd = st->data;
- struct dst_trans *t;
- int err = 0;
- struct bio *bio;
-
- mutex_lock(&n->trans_lock);
- t = dst_trans_search(n, cmd->id);
- mutex_unlock(&n->trans_lock);
-
- if (!t)
- goto err_out_exit;
-
- bio = t->bio;
-
- dprintk("%s: bio: %llu/%u, cmd_size: %u, csize: %u, dir: %lu.\n",
- __func__, (u64)bio->bi_sector, bio->bi_size, cmd->size,
- cmd->csize, bio_data_dir(bio));
-
- if (bio_data_dir(bio) == READ) {
- if (bio->bi_size != cmd->size - cmd->csize)
- goto err_out_exit;
-
- if (dst_need_crypto(n)) {
- err = dst_recv_cdata(st, t->cmd.hash);
- if (err)
- goto err_out_exit;
- }
-
- err = dst_recv_bio(st, t->bio, bio->bi_size);
- if (err)
- goto err_out_exit;
-
- if (dst_need_crypto(n))
- return dst_trans_crypto(t);
- } else {
- err = -EBADMSG;
- if (cmd->size || cmd->csize)
- goto err_out_exit;
- }
-
- dst_trans_remove(t);
- dst_trans_put(t);
-
- return 0;
-
-err_out_exit:
- return err;
-}
-
-/*
- * Receive crypto data.
- */
-int dst_recv_cdata(struct dst_state *st, void *cdata)
-{
- struct dst_cmd *cmd = st->data;
- struct dst_node *n = st->node;
- struct dst_crypto_ctl *c = &n->crypto;
- int err;
-
- if (cmd->csize != c->crypto_attached_size) {
- dprintk("%s: cmd: cmd: %u, sector: %llu, size: %u, "
- "csize: %u != digest size %u.\n",
- __func__, cmd->cmd, cmd->sector, cmd->size,
- cmd->csize, c->crypto_attached_size);
- err = -EINVAL;
- goto err_out_exit;
- }
-
- err = dst_data_recv(st, cdata, cmd->csize);
- if (err)
- goto err_out_exit;
-
- cmd->size -= cmd->csize;
- return 0;
-
-err_out_exit:
- return err;
-}
-
-/*
- * Receive the command and start its processing.
- */
-static int dst_recv_processing(struct dst_state *st)
-{
- int err = -EINTR;
- struct dst_cmd *cmd = st->data;
-
- /*
- * If socket will be reset after this statement, then
- * dst_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 = dst_data_recv(st, cmd, sizeof(struct dst_cmd));
- if (err)
- goto out_exit;
-
- dst_convert_cmd(cmd);
-
- dprintk("%s: cmd: %u, size: %u, csize: %u, id: %llu, "
- "sector: %llu, flags: %llx, rw: %llx.\n",
- __func__, cmd->cmd, cmd->size,
- cmd->csize, cmd->id, cmd->sector,
- cmd->flags, cmd->rw);
-
- /*
- * This should catch protocol breakage and random garbage
- * instead of commands.
- */
- if (unlikely(cmd->csize > st->size - sizeof(struct dst_cmd))) {
- err = -EBADMSG;
- goto out_exit;
- }
-
- err = -EPROTO;
- switch (cmd->cmd) {
- case DST_IO_RESPONSE:
- err = dst_process_io_response(st);
- break;
- case DST_IO:
- err = dst_process_io(st);
- break;
- case DST_CFG:
- err = dst_process_cfg(st);
- break;
- case DST_PING:
- err = 0;
- break;
- default:
- break;
- }
-
-out_exit:
- return err;
-}
-
-/*
- * Receiving thread. For the client node we should try to reconnect,
- * for accepted client we just drop the state and expect it to reconnect.
- */
-static int dst_recv(void *init_data, void *schedule_data)
-{
- struct dst_state *st = schedule_data;
- struct dst_node *n = init_data;
- int err = 0;
-
- dprintk("%s: start st: %p, n: %p, scan: %lu, need_exit: %d.\n",
- __func__, st, n, n->trans_scan_timeout, st->need_exit);
-
- while (n->trans_scan_timeout && !st->need_exit) {
- err = dst_recv_processing(st);
- if (err < 0) {
- if (!st->ctl.type)
- break;
-
- if (!n->trans_scan_timeout || st->need_exit)
- break;
-
- dst_state_reset(st);
- msleep(1000);
- }
- }
-
- st->need_exit = 1;
- wake_up(&st->thread_wait);
-
- dprintk("%s: freeing receiving socket st: %p.\n", __func__, st);
- dst_state_lock(st);
- dst_state_exit_connected(st);
- dst_state_unlock(st);
- dst_state_put(st);
-
- dprintk("%s: freed receiving socket st: %p.\n", __func__, st);
-
- return err;
-}
-
-/*
- * Network state dies here and borns couple of lines below.
- * This object is the main network state processing engine:
- * sending, receiving, reconnections, all network related
- * tasks are handled on behalf of the state.
- */
-static void dst_state_free(struct dst_state *st)
-{
- dprintk("%s: st: %p.\n", __func__, st);
- if (st->cleanup)
- st->cleanup(st);
- kfree(st->data);
- kfree(st);
-}
-
-struct dst_state *dst_state_alloc(struct dst_node *n)
-{
- struct dst_state *st;
- int err = -ENOMEM;
-
- st = kzalloc(sizeof(struct dst_state), GFP_KERNEL);
- if (!st)
- goto err_out_exit;
-
- st->node = n;
- st->need_exit = 0;
-
- st->size = PAGE_SIZE;
- st->data = kmalloc(st->size, GFP_KERNEL);
- if (!st->data)
- goto err_out_free;
-
- spin_lock_init(&st->request_lock);
- INIT_LIST_HEAD(&st->request_list);
-
- mutex_init(&st->state_lock);
- init_waitqueue_head(&st->thread_wait);
-
- /*
- * One for processing thread, another one for node itself.
- */
- atomic_set(&st->refcnt, 2);
-
- dprintk("%s: st: %p, n: %p.\n", __func__, st, st->node);
-
- return st;
-
-err_out_free:
- kfree(st);
-err_out_exit:
- return ERR_PTR(err);
-}
-
-int dst_state_schedule_receiver(struct dst_state *st)
-{
- return thread_pool_schedule_private(st->node->pool, dst_thread_setup,
- dst_recv, st, MAX_SCHEDULE_TIMEOUT, st->node);
-}
-
-/*
- * Initialize client's connection to the remote peer: allocate state,
- * connect and perform block IO autoconfiguration.
- */
-int dst_node_init_connected(struct dst_node *n, struct dst_network_ctl *r)
-{
- struct dst_state *st;
- int err = -ENOMEM;
-
- st = dst_state_alloc(n);
- if (IS_ERR(st)) {
- err = PTR_ERR(st);
- goto err_out_exit;
- }
- memcpy(&st->ctl, r, sizeof(struct dst_network_ctl));
-
- err = dst_state_init_connected(st);
- if (err)
- goto err_out_free_data;
-
- err = dst_request_remote_config(st);
- if (err)
- goto err_out_exit_connected;
- n->state = st;
-
- err = dst_state_schedule_receiver(st);
- if (err)
- goto err_out_exit_connected;
-
- return 0;
-
-err_out_exit_connected:
- dst_state_exit_connected(st);
-err_out_free_data:
- dst_state_free(st);
-err_out_exit:
- n->state = NULL;
- return err;
-}
-
-void dst_state_put(struct dst_state *st)
-{
- dprintk("%s: st: %p, refcnt: %d.\n",
- __func__, st, atomic_read(&st->refcnt));
- if (atomic_dec_and_test(&st->refcnt))
- dst_state_free(st);
-}
-
-/*
- * Send block IO to the network one by one using zero-copy ->sendpage().
- */
-int dst_send_bio(struct dst_state *st, struct dst_cmd *cmd, struct bio *bio)
-{
- struct bio_vec *bv;
- struct dst_crypto_ctl *c = &st->node->crypto;
- int err, i = 0;
- int flags = MSG_WAITALL;
-
- err = dst_data_send_header(st->socket, cmd,
- sizeof(struct dst_cmd) + c->crypto_attached_size, bio->bi_vcnt);
- if (err)
- goto err_out_exit;
-
- bio_for_each_segment(bv, bio, i) {
- if (i < bio->bi_vcnt - 1)
- flags |= MSG_MORE;
-
- err = kernel_sendpage(st->socket, bv->bv_page, bv->bv_offset,
- bv->bv_len, flags);
- if (err <= 0)
- goto err_out_exit;
- }
-
- return 0;
-
-err_out_exit:
- dprintk("%s: %d/%d, flags: %x, err: %d.\n",
- __func__, i, bio->bi_vcnt, flags, err);
- return err;
-}
-
-/*
- * Send transaction to the remote peer.
- */
-int dst_trans_send(struct dst_trans *t)
-{
- int err;
- struct dst_state *st = t->n->state;
- struct bio *bio = t->bio;
-
- dst_convert_cmd(&t->cmd);
-
- dst_state_lock(st);
- if (!st->socket) {
- err = dst_state_init_connected(st);
- if (err)
- goto err_out_unlock;
- }
-
- if (bio_data_dir(bio) == WRITE) {
- err = dst_send_bio(st, &t->cmd, t->bio);
- } else {
- err = dst_data_send_header(st->socket, &t->cmd,
- sizeof(struct dst_cmd), 0);
- }
- if (err)
- goto err_out_reset;
-
- dst_state_unlock(st);
- return 0;
-
-err_out_reset:
- dst_state_reset_nolock(st);
-err_out_unlock:
- dst_state_unlock(st);
-
- return err;
-}