aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--drivers/staging/pohmelfs/trans.c715
1 files changed, 715 insertions, 0 deletions
diff --git a/drivers/staging/pohmelfs/trans.c b/drivers/staging/pohmelfs/trans.c
new file mode 100644
index 00000000000..92054bdc154
--- /dev/null
+++ b/drivers/staging/pohmelfs/trans.c
@@ -0,0 +1,715 @@
+/*
+ * 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/module.h>
+#include <linux/crypto.h>
+#include <linux/fs.h>
+#include <linux/jhash.h>
+#include <linux/hash.h>
+#include <linux/ktime.h>
+#include <linux/mempool.h>
+#include <linux/mm.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/parser.h>
+#include <linux/poll.h>
+#include <linux/swap.h>
+#include <linux/slab.h>
+#include <linux/statfs.h>
+#include <linux/writeback.h>
+
+#include "netfs.h"
+
+static struct kmem_cache *netfs_trans_dst;
+static mempool_t *netfs_trans_dst_pool;
+
+static void netfs_trans_init_static(struct netfs_trans *t, int num, int size)
+{
+ t->page_num = num;
+ t->total_size = size;
+ atomic_set(&t->refcnt, 1);
+
+ spin_lock_init(&t->dst_lock);
+ INIT_LIST_HEAD(&t->dst_list);
+}
+
+static int netfs_trans_send_pages(struct netfs_trans *t, struct netfs_state *st)
+{
+ int err = 0;
+ unsigned int i, attached_pages = t->attached_pages, ci;
+ struct msghdr msg;
+ struct page **pages = (t->eng)?t->eng->pages:t->pages;
+ struct page *p;
+ unsigned int size;
+
+ msg.msg_name = NULL;
+ msg.msg_namelen = 0;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_flags = MSG_WAITALL | MSG_MORE;
+
+ ci = 0;
+ for (i=0; i<t->page_num; ++i) {
+ struct page *page = pages[ci];
+ struct netfs_cmd cmd;
+ struct iovec io;
+
+ p = t->pages[i];
+
+ if (!p)
+ continue;
+
+ size = page_private(p);
+
+ io.iov_base = &cmd;
+ io.iov_len = sizeof(struct netfs_cmd);
+
+ cmd.cmd = NETFS_WRITE_PAGE;
+ cmd.ext = 0;
+ cmd.id = 0;
+ cmd.size = size;
+ cmd.start = p->index;
+ cmd.start <<= PAGE_CACHE_SHIFT;
+ cmd.csize = 0;
+ cmd.cpad = 0;
+ cmd.iv = pohmelfs_gen_iv(t);
+
+ netfs_convert_cmd(&cmd);
+
+ msg.msg_iov = &io;
+ msg.msg_iovlen = 1;
+ msg.msg_flags = MSG_WAITALL | MSG_MORE;
+
+ err = kernel_sendmsg(st->socket, &msg, (struct kvec *)msg.msg_iov, 1, sizeof(struct netfs_cmd));
+ if (err <= 0) {
+ printk("%s: %d/%d failed to send transaction header: t: %p, gen: %u, err: %d.\n",
+ __func__, i, t->page_num, t, t->gen, err);
+ if (err == 0)
+ err = -ECONNRESET;
+ goto err_out;
+ }
+
+ msg.msg_flags = MSG_WAITALL|(attached_pages == 1)?0:MSG_MORE;
+
+ err = kernel_sendpage(st->socket, page, 0, size, msg.msg_flags);
+ if (err <= 0) {
+ printk("%s: %d/%d failed to send transaction page: t: %p, gen: %u, size: %u, err: %d.\n",
+ __func__, i, t->page_num, t, t->gen, size, err);
+ if (err == 0)
+ err = -ECONNRESET;
+ goto err_out;
+ }
+
+ dprintk("%s: %d/%d sent t: %p, gen: %u, page: %p/%p, size: %u.\n",
+ __func__, i, t->page_num, t, t->gen, page, p, size);
+
+ err = 0;
+ attached_pages--;
+ if (!attached_pages)
+ break;
+ ci++;
+
+ continue;
+
+err_out:
+ printk("%s: t: %p, gen: %u, err: %d.\n", __func__, t, t->gen, err);
+ netfs_state_exit(st);
+ break;
+ }
+
+ return err;
+}
+
+int netfs_trans_send(struct netfs_trans *t, struct netfs_state *st)
+{
+ int err;
+ struct msghdr msg;
+
+ BUG_ON(!t->iovec.iov_len);
+ BUG_ON(t->iovec.iov_len > 1024*1024*1024);
+
+ netfs_state_lock_send(st);
+ if (!st->socket) {
+ err = netfs_state_init(st);
+ if (err)
+ goto err_out_unlock_return;
+ }
+
+ msg.msg_iov = &t->iovec;
+ 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;
+
+ if (t->attached_pages)
+ msg.msg_flags |= MSG_MORE;
+
+ err = kernel_sendmsg(st->socket, &msg, (struct kvec *)msg.msg_iov, 1, t->iovec.iov_len);
+ if (err <= 0) {
+ printk("%s: failed to send contig transaction: t: %p, gen: %u, size: %u, err: %d.\n",
+ __func__, t, t->gen, t->iovec.iov_len, err);
+ if (err == 0)
+ err = -ECONNRESET;
+ goto err_out_unlock_return;
+ }
+
+ dprintk("%s: sent %s transaction: t: %p, gen: %u, size: %u, page_num: %u.\n",
+ __func__, (t->page_num)?"partial":"full",
+ t, t->gen, t->iovec.iov_len, t->page_num);
+
+ err = 0;
+ if (t->attached_pages)
+ err = netfs_trans_send_pages(t, st);
+
+err_out_unlock_return:
+
+ if (st->need_reset) {
+ netfs_state_exit(st);
+ }
+ netfs_state_unlock_send(st);
+
+ dprintk("%s: t: %p, gen: %u, err: %d.\n",
+ __func__, t, t->gen, err);
+
+ t->result = err;
+ return err;
+}
+
+static inline int netfs_trans_cmp(unsigned int gen, unsigned int new)
+{
+ if (gen < new)
+ return 1;
+ if (gen > new)
+ return -1;
+ return 0;
+}
+
+struct netfs_trans_dst *netfs_trans_search(struct netfs_state *st, unsigned int gen)
+{
+ struct rb_root *root = &st->trans_root;
+ struct rb_node *n = root->rb_node;
+ struct netfs_trans_dst *tmp, *ret = NULL;
+ struct netfs_trans *t;
+ int cmp;
+
+ while (n) {
+ tmp = rb_entry(n, struct netfs_trans_dst, state_entry);
+ t = tmp->trans;
+
+ cmp = netfs_trans_cmp(t->gen, gen);
+ if (cmp < 0)
+ n = n->rb_left;
+ else if (cmp > 0)
+ n = n->rb_right;
+ else {
+ ret = tmp;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int netfs_trans_insert(struct netfs_trans_dst *ndst, struct netfs_state *st)
+{
+ struct rb_root *root = &st->trans_root;
+ struct rb_node **n = &root->rb_node, *parent = NULL;
+ struct netfs_trans_dst *ret = NULL, *tmp;
+ struct netfs_trans *t = NULL, *new = ndst->trans;
+ int cmp;
+
+ while (*n) {
+ parent = *n;
+
+ tmp = rb_entry(parent, struct netfs_trans_dst, state_entry);
+ t = tmp->trans;
+
+ cmp = netfs_trans_cmp(t->gen, new->gen);
+ if (cmp < 0)
+ n = &parent->rb_left;
+ else if (cmp > 0)
+ n = &parent->rb_right;
+ else {
+ ret = tmp;
+ break;
+ }
+ }
+
+ if (ret) {
+ printk("%s: exist: old: gen: %u, flags: %x, send_time: %lu, "
+ "new: gen: %u, flags: %x, send_time: %lu.\n",
+ __func__, t->gen, t->flags, ret->send_time,
+ new->gen, new->flags, ndst->send_time);
+ return -EEXIST;
+ }
+
+ rb_link_node(&ndst->state_entry, parent, n);
+ rb_insert_color(&ndst->state_entry, root);
+ ndst->send_time = jiffies;
+
+ return 0;
+}
+
+int netfs_trans_remove_nolock(struct netfs_trans_dst *dst, struct netfs_state *st)
+{
+ if (dst && dst->state_entry.rb_parent_color) {
+ rb_erase(&dst->state_entry, &st->trans_root);
+ dst->state_entry.rb_parent_color = 0;
+ return 1;
+ }
+ return 0;
+}
+
+static int netfs_trans_remove_state(struct netfs_trans_dst *dst)
+{
+ int ret;
+ struct netfs_state *st = dst->state;
+
+ mutex_lock(&st->trans_lock);
+ ret = netfs_trans_remove_nolock(dst, st);
+ mutex_unlock(&st->trans_lock);
+
+ return ret;
+}
+
+/*
+ * Create new destination for given transaction associated with given network state.
+ * Transaction's reference counter is bumped and will be dropped when either
+ * reply is received or when async timeout detection task will fail resending
+ * and drop transaction.
+ */
+static int netfs_trans_push_dst(struct netfs_trans *t, struct netfs_state *st)
+{
+ struct netfs_trans_dst *dst;
+ int err;
+
+ dst = mempool_alloc(netfs_trans_dst_pool, GFP_KERNEL);
+ if (!dst)
+ return -ENOMEM;
+
+ dst->retries = 0;
+ dst->send_time = 0;
+ dst->state = st;
+ dst->trans = t;
+ netfs_trans_get(t);
+
+ mutex_lock(&st->trans_lock);
+ err = netfs_trans_insert(dst, st);
+ mutex_unlock(&st->trans_lock);
+
+ if (err)
+ goto err_out_free;
+
+ spin_lock(&t->dst_lock);
+ list_add_tail(&dst->trans_entry, &t->dst_list);
+ spin_unlock(&t->dst_lock);
+
+ return 0;
+
+err_out_free:
+ t->result = err;
+ netfs_trans_put(t);
+ mempool_free(dst, netfs_trans_dst_pool);
+ return err;
+}
+
+static void netfs_trans_free_dst(struct netfs_trans_dst *dst)
+{
+ netfs_trans_put(dst->trans);
+ mempool_free(dst, netfs_trans_dst_pool);
+}
+
+static void netfs_trans_remove_dst(struct netfs_trans_dst *dst)
+{
+ if (netfs_trans_remove_state(dst))
+ netfs_trans_free_dst(dst);
+}
+
+/*
+ * Drop destination transaction entry when we know it.
+ */
+void netfs_trans_drop_dst(struct netfs_trans_dst *dst)
+{
+ struct netfs_trans *t = dst->trans;
+
+ spin_lock(&t->dst_lock);
+ list_del_init(&dst->trans_entry);
+ spin_unlock(&t->dst_lock);
+
+ netfs_trans_remove_dst(dst);
+}
+
+/*
+ * Drop destination transaction entry when we know it and when we
+ * already removed dst from state tree.
+ */
+void netfs_trans_drop_dst_nostate(struct netfs_trans_dst *dst)
+{
+ struct netfs_trans *t = dst->trans;
+
+ spin_lock(&t->dst_lock);
+ list_del_init(&dst->trans_entry);
+ spin_unlock(&t->dst_lock);
+
+ netfs_trans_free_dst(dst);
+}
+
+/*
+ * This drops destination transaction entry from appropriate network state
+ * tree and drops related reference counter. It is possible that transaction
+ * will be freed here if its reference counter hits zero.
+ * Destination transaction entry will be freed.
+ */
+void netfs_trans_drop_trans(struct netfs_trans *t, struct netfs_state *st)
+{
+ struct netfs_trans_dst *dst, *tmp, *ret = NULL;
+
+ spin_lock(&t->dst_lock);
+ list_for_each_entry_safe(dst, tmp, &t->dst_list, trans_entry) {
+ if (dst->state == st) {
+ ret = dst;
+ list_del(&dst->trans_entry);
+ break;
+ }
+ }
+ spin_unlock(&t->dst_lock);
+
+ if (ret)
+ netfs_trans_remove_dst(ret);
+}
+
+/*
+ * This drops destination transaction entry from appropriate network state
+ * tree and drops related reference counter. It is possible that transaction
+ * will be freed here if its reference counter hits zero.
+ * Destination transaction entry will be freed.
+ */
+void netfs_trans_drop_last(struct netfs_trans *t, struct netfs_state *st)
+{
+ struct netfs_trans_dst *dst, *tmp, *ret;
+
+ spin_lock(&t->dst_lock);
+ ret = list_entry(t->dst_list.prev, struct netfs_trans_dst, trans_entry);
+ if (ret->state != st) {
+ ret = NULL;
+ list_for_each_entry_safe(dst, tmp, &t->dst_list, trans_entry) {
+ if (dst->state == st) {
+ ret = dst;
+ list_del_init(&dst->trans_entry);
+ break;
+ }
+ }
+ } else {
+ list_del(&ret->trans_entry);
+ }
+ spin_unlock(&t->dst_lock);
+
+ if (ret)
+ netfs_trans_remove_dst(ret);
+}
+
+static int netfs_trans_push(struct netfs_trans *t, struct netfs_state *st)
+{
+ int err;
+
+ err = netfs_trans_push_dst(t, st);
+ if (err)
+ return err;
+
+ err = netfs_trans_send(t, st);
+ if (err)
+ goto err_out_free;
+
+ if (t->flags & NETFS_TRANS_SINGLE_DST)
+ pohmelfs_switch_active(st->psb);
+
+ return 0;
+
+err_out_free:
+ t->result = err;
+ netfs_trans_drop_last(t, st);
+
+ return err;
+}
+
+int netfs_trans_finish_send(struct netfs_trans *t, struct pohmelfs_sb *psb)
+{
+ struct pohmelfs_config *c;
+ int err = -ENODEV;
+ struct netfs_state *st;
+#if 0
+ dprintk("%s: t: %p, gen: %u, size: %u, page_num: %u, active: %p.\n",
+ __func__, t, t->gen, t->iovec.iov_len, t->page_num, psb->active_state);
+#endif
+ mutex_lock(&psb->state_lock);
+
+ if ((t->flags & NETFS_TRANS_SINGLE_DST) && psb->active_state) {
+ st = &psb->active_state->state;
+
+ err = -EPIPE;
+ if (netfs_state_poll(st) & POLLOUT) {
+ err = netfs_trans_push_dst(t, st);
+ if (!err) {
+ err = netfs_trans_send(t, st);
+ if (err) {
+ netfs_trans_drop_last(t, st);
+ } else {
+ pohmelfs_switch_active(psb);
+ goto out;
+ }
+ }
+ }
+ pohmelfs_switch_active(psb);
+ }
+
+ list_for_each_entry(c, &psb->state_list, config_entry) {
+ st = &c->state;
+
+ err = netfs_trans_push(t, st);
+ if (!err && (t->flags & NETFS_TRANS_SINGLE_DST))
+ break;
+ }
+out:
+ mutex_unlock(&psb->state_lock);
+#if 0
+ dprintk("%s: fully sent t: %p, gen: %u, size: %u, page_num: %u, err: %d.\n",
+ __func__, t, t->gen, t->iovec.iov_len, t->page_num, err);
+#endif
+ if (err)
+ t->result = err;
+ return err;
+}
+
+int netfs_trans_finish(struct netfs_trans *t, struct pohmelfs_sb *psb)
+{
+ int err;
+ struct netfs_cmd *cmd = t->iovec.iov_base;
+
+ t->gen = atomic_inc_return(&psb->trans_gen);
+
+ pohmelfs_ftrans_clean(t->gen);
+
+ cmd->size = t->iovec.iov_len - sizeof(struct netfs_cmd) +
+ t->attached_size + t->attached_pages * sizeof(struct netfs_cmd);
+ cmd->cmd = NETFS_TRANS;
+ cmd->start = t->gen;
+ cmd->id = 0;
+
+ if (psb->perform_crypto) {
+ cmd->ext = psb->crypto_attached_size;
+ cmd->csize = psb->crypto_attached_size;
+ }
+
+ dprintk("%s: t: %u, size: %u, iov_len: %u, attached_size: %u, attached_pages: %u.\n",
+ __func__, t->gen, cmd->size, t->iovec.iov_len, t->attached_size, t->attached_pages);
+ err = pohmelfs_trans_crypt(t, psb);
+ if (err) {
+ t->result = err;
+ netfs_convert_cmd(cmd);
+ dprintk("%s: trans: %llu, crypto_attached_size: %u, attached_size: %u, attached_pages: %d, trans_size: %u, err: %d.\n",
+ __func__, cmd->start, psb->crypto_attached_size, t->attached_size, t->attached_pages, cmd->size, err);
+ }
+ netfs_trans_put(t);
+ return err;
+}
+
+/*
+ * Resend transaction to remote server(s).
+ * If new servers were added into superblock, we can try to send data
+ * to them too.
+ *
+ * It is called under superblock's state_lock, so we can safely
+ * dereference psb->state_list. Also, transaction's reference counter is
+ * bumped, so it can not go away under us, thus we can safely access all
+ * its members. State is locked.
+ *
+ * This function returns 0 if transaction was successfully sent to at
+ * least one destination target.
+ */
+int netfs_trans_resend(struct netfs_trans *t, struct pohmelfs_sb *psb)
+{
+ struct netfs_trans_dst *dst;
+ struct netfs_state *st;
+ struct pohmelfs_config *c;
+ int err, exist, error = -ENODEV;
+
+ list_for_each_entry(c, &psb->state_list, config_entry) {
+ st = &c->state;
+
+ exist = 0;
+ spin_lock(&t->dst_lock);
+ list_for_each_entry(dst, &t->dst_list, trans_entry) {
+ if (st == dst->state) {
+ exist = 1;
+ break;
+ }
+ }
+ spin_unlock(&t->dst_lock);
+
+ if (exist) {
+ if (!(t->flags & NETFS_TRANS_SINGLE_DST) ||
+ (c->config_entry.next == &psb->state_list)) {
+ dprintk("%s: resending st: %p, t: %p, gen: %u.\n",
+ __func__, st, t, t->gen);
+ err = netfs_trans_send(t, st);
+ if (!err)
+ error = 0;
+ }
+ continue;
+ }
+
+ dprintk("%s: pushing/resending st: %p, t: %p, gen: %u.\n",
+ __func__, st, t, t->gen);
+ err = netfs_trans_push(t, st);
+ if (err)
+ continue;
+ error = 0;
+ if (t->flags & NETFS_TRANS_SINGLE_DST)
+ break;
+ }
+
+ t->result = error;
+ return error;
+}
+
+void *netfs_trans_add(struct netfs_trans *t, unsigned int size)
+{
+ struct iovec *io = &t->iovec;
+ void *ptr;
+
+ if (size > t->total_size) {
+ ptr = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ if (io->iov_len + size > t->total_size) {
+ dprintk("%s: too big size t: %p, gen: %u, iov_len: %u, size: %u, total: %u.\n",
+ __func__, t, t->gen, io->iov_len, size, t->total_size);
+ ptr = ERR_PTR(-E2BIG);
+ goto out;
+ }
+
+ ptr = io->iov_base + io->iov_len;
+ io->iov_len += size;
+
+out:
+ dprintk("%s: t: %p, gen: %u, size: %u, total: %u.\n",
+ __func__, t, t->gen, size, io->iov_len);
+ return ptr;
+}
+
+void netfs_trans_free(struct netfs_trans *t)
+{
+ if (t->eng)
+ pohmelfs_crypto_thread_make_ready(t->eng->thread);
+ kfree(t);
+}
+
+struct netfs_trans *netfs_trans_alloc(struct pohmelfs_sb *psb, unsigned int size,
+ unsigned int flags, unsigned int nr)
+{
+ struct netfs_trans *t;
+ unsigned int num, cont, pad, size_no_trans;
+ unsigned int crypto_added = 0;
+ struct netfs_cmd *cmd;
+
+ if (psb->perform_crypto)
+ crypto_added = psb->crypto_attached_size;
+
+ /*
+ * |sizeof(struct netfs_trans)|
+ * |sizeof(struct netfs_cmd)| - transaction header
+ * |size| - buffer with requested size
+ * |padding| - crypto padding, zero bytes
+ * |nr * sizeof(struct page *)| - array of page pointers
+ *
+ * Overall size should be less than PAGE_SIZE for guaranteed allocation.
+ */
+
+ cont = size;
+ size = ALIGN(size, psb->crypto_align_size);
+ pad = size - cont;
+
+ size_no_trans = size + sizeof(struct netfs_cmd) * 2 + crypto_added;
+
+ cont = sizeof(struct netfs_trans) + size_no_trans;
+
+ num = (PAGE_SIZE - cont)/sizeof(struct page *);
+
+ if (nr > num)
+ nr = num;
+
+ t = kzalloc(cont + nr*sizeof(struct page *), GFP_NOIO);
+ if (!t)
+ goto err_out_exit;
+
+ t->iovec.iov_base = (void *)(t + 1);
+ t->pages = (struct page **)(t->iovec.iov_base + size_no_trans);
+
+ /*
+ * Reserving space for transaction header.
+ */
+ t->iovec.iov_len = sizeof(struct netfs_cmd) + crypto_added;
+
+ netfs_trans_init_static(t, nr, size_no_trans);
+
+ t->flags = flags;
+ t->psb = psb;
+
+ cmd = (struct netfs_cmd *)t->iovec.iov_base;
+
+ cmd->size = size;
+ cmd->cpad = pad;
+ cmd->csize = crypto_added;
+
+ dprintk("%s: t: %p, gen: %u, size: %u, padding: %u, align_size: %u, flags: %x, "
+ "page_num: %u, base: %p, pages: %p.\n",
+ __func__, t, t->gen, size, pad, psb->crypto_align_size, flags, nr,
+ t->iovec.iov_base, t->pages);
+
+ return t;
+
+err_out_exit:
+ return NULL;
+}
+
+int netfs_trans_init(void)
+{
+ int err = -ENOMEM;
+
+ netfs_trans_dst = kmem_cache_create("netfs_trans_dst", sizeof(struct netfs_trans_dst),
+ 0, 0, NULL);
+ if (!netfs_trans_dst)
+ goto err_out_exit;
+
+ netfs_trans_dst_pool = mempool_create_slab_pool(256, netfs_trans_dst);
+ if (!netfs_trans_dst_pool)
+ goto err_out_free;
+
+ return 0;
+
+err_out_free:
+ kmem_cache_destroy(netfs_trans_dst);
+err_out_exit:
+ return err;
+}
+
+void netfs_trans_exit(void)
+{
+ mempool_destroy(netfs_trans_dst_pool);
+ kmem_cache_destroy(netfs_trans_dst);
+}