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authorLinus Torvalds <torvalds@linux-foundation.org>2020-10-13 08:59:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-10-13 08:59:39 -0700
commitc024a81125ca2999d563d40cf4cedba771c2dc77 (patch)
treed8bdafdf478332049a62ad5b7a6d2666c95df6f6 /fs
parent6f5032a852f9bf3c449db58a9209ba267f11869a (diff)
parent4f2b30fd9b4bd6e3620fe55786df7fc5f89ad526 (diff)
downloadlinux-stericsson-c024a81125ca2999d563d40cf4cedba771c2dc77.tar.gz
Merge tag 'dlm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm
Pull dlm updates from David Teigland: "This set continues the ongoing rework of the low level communication layer in the dlm. The focus here is on improvements to connection handling, and reworking the receiving of messages" * tag 'dlm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm: fs: dlm: fix race in nodeid2con fs: dlm: rework receive handling fs: dlm: disallow buffer size below default fs: dlm: handle range check as callback fs: dlm: fix mark per nodeid setting fs: dlm: remove lock dependency warning fs: dlm: use free_con to free connection fs: dlm: handle possible othercon writequeues fs: dlm: move free writequeue into con free fs: dlm: fix configfs memory leak fs: dlm: fix dlm_local_addr memory leak fs: dlm: make connection hash lockless fs: dlm: synchronize dlm before shutdown
Diffstat (limited to 'fs')
-rw-r--r--fs/dlm/Kconfig1
-rw-r--r--fs/dlm/config.c66
-rw-r--r--fs/dlm/config.h4
-rw-r--r--fs/dlm/lowcomms.c329
-rw-r--r--fs/dlm/midcomms.c136
-rw-r--r--fs/dlm/midcomms.h3
6 files changed, 260 insertions, 279 deletions
diff --git a/fs/dlm/Kconfig b/fs/dlm/Kconfig
index f82a4952769d..ee92634196a8 100644
--- a/fs/dlm/Kconfig
+++ b/fs/dlm/Kconfig
@@ -4,6 +4,7 @@ menuconfig DLM
depends on INET
depends on SYSFS && CONFIGFS_FS && (IPV6 || IPV6=n)
select IP_SCTP
+ select SRCU
help
A general purpose distributed lock manager for kernel or userspace
applications.
diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index 47f0b98b707f..49c5f9407098 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -125,7 +125,7 @@ static ssize_t cluster_cluster_name_store(struct config_item *item,
CONFIGFS_ATTR(cluster_, cluster_name);
static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
- int *info_field, int check_zero,
+ int *info_field, bool (*check_cb)(unsigned int x),
const char *buf, size_t len)
{
unsigned int x;
@@ -137,7 +137,7 @@ static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
if (rc)
return rc;
- if (check_zero && !x)
+ if (check_cb && check_cb(x))
return -EINVAL;
*cl_field = x;
@@ -146,13 +146,13 @@ static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
return len;
}
-#define CLUSTER_ATTR(name, check_zero) \
+#define CLUSTER_ATTR(name, check_cb) \
static ssize_t cluster_##name##_store(struct config_item *item, \
const char *buf, size_t len) \
{ \
struct dlm_cluster *cl = config_item_to_cluster(item); \
return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name, \
- check_zero, buf, len); \
+ check_cb, buf, len); \
} \
static ssize_t cluster_##name##_show(struct config_item *item, char *buf) \
{ \
@@ -161,20 +161,30 @@ static ssize_t cluster_##name##_show(struct config_item *item, char *buf) \
} \
CONFIGFS_ATTR(cluster_, name);
-CLUSTER_ATTR(tcp_port, 1);
-CLUSTER_ATTR(buffer_size, 1);
-CLUSTER_ATTR(rsbtbl_size, 1);
-CLUSTER_ATTR(recover_timer, 1);
-CLUSTER_ATTR(toss_secs, 1);
-CLUSTER_ATTR(scan_secs, 1);
-CLUSTER_ATTR(log_debug, 0);
-CLUSTER_ATTR(log_info, 0);
-CLUSTER_ATTR(protocol, 0);
-CLUSTER_ATTR(mark, 0);
-CLUSTER_ATTR(timewarn_cs, 1);
-CLUSTER_ATTR(waitwarn_us, 0);
-CLUSTER_ATTR(new_rsb_count, 0);
-CLUSTER_ATTR(recover_callbacks, 0);
+static bool dlm_check_zero(unsigned int x)
+{
+ return !x;
+}
+
+static bool dlm_check_buffer_size(unsigned int x)
+{
+ return (x < DEFAULT_BUFFER_SIZE);
+}
+
+CLUSTER_ATTR(tcp_port, dlm_check_zero);
+CLUSTER_ATTR(buffer_size, dlm_check_buffer_size);
+CLUSTER_ATTR(rsbtbl_size, dlm_check_zero);
+CLUSTER_ATTR(recover_timer, dlm_check_zero);
+CLUSTER_ATTR(toss_secs, dlm_check_zero);
+CLUSTER_ATTR(scan_secs, dlm_check_zero);
+CLUSTER_ATTR(log_debug, NULL);
+CLUSTER_ATTR(log_info, NULL);
+CLUSTER_ATTR(protocol, NULL);
+CLUSTER_ATTR(mark, NULL);
+CLUSTER_ATTR(timewarn_cs, dlm_check_zero);
+CLUSTER_ATTR(waitwarn_us, NULL);
+CLUSTER_ATTR(new_rsb_count, NULL);
+CLUSTER_ATTR(recover_callbacks, NULL);
static struct configfs_attribute *cluster_attrs[] = {
[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port,
@@ -221,6 +231,7 @@ struct dlm_space {
struct list_head members;
struct mutex members_lock;
int members_count;
+ struct dlm_nodes *nds;
};
struct dlm_comms {
@@ -430,6 +441,7 @@ static struct config_group *make_space(struct config_group *g, const char *name)
INIT_LIST_HEAD(&sp->members);
mutex_init(&sp->members_lock);
sp->members_count = 0;
+ sp->nds = nds;
return &sp->group;
fail:
@@ -451,6 +463,7 @@ static void drop_space(struct config_group *g, struct config_item *i)
static void release_space(struct config_item *i)
{
struct dlm_space *sp = config_item_to_space(i);
+ kfree(sp->nds);
kfree(sp);
}
@@ -857,18 +870,22 @@ int dlm_comm_seq(int nodeid, uint32_t *seq)
return 0;
}
-int dlm_comm_mark(int nodeid, unsigned int *mark)
+void dlm_comm_mark(int nodeid, unsigned int *mark)
{
struct dlm_comm *cm;
cm = get_comm(nodeid);
- if (!cm)
- return -ENOENT;
+ if (!cm) {
+ *mark = dlm_config.ci_mark;
+ return;
+ }
- *mark = cm->mark;
- put_comm(cm);
+ if (cm->mark)
+ *mark = cm->mark;
+ else
+ *mark = dlm_config.ci_mark;
- return 0;
+ put_comm(cm);
}
int dlm_our_nodeid(void)
@@ -889,7 +906,6 @@ int dlm_our_addr(struct sockaddr_storage *addr, int num)
/* Config file defaults */
#define DEFAULT_TCP_PORT 21064
-#define DEFAULT_BUFFER_SIZE 4096
#define DEFAULT_RSBTBL_SIZE 1024
#define DEFAULT_RECOVER_TIMER 5
#define DEFAULT_TOSS_SECS 10
diff --git a/fs/dlm/config.h b/fs/dlm/config.h
index f62996cad561..c210250a2581 100644
--- a/fs/dlm/config.h
+++ b/fs/dlm/config.h
@@ -12,6 +12,8 @@
#ifndef __CONFIG_DOT_H__
#define __CONFIG_DOT_H__
+#define DEFAULT_BUFFER_SIZE 4096
+
struct dlm_config_node {
int nodeid;
int weight;
@@ -46,7 +48,7 @@ void dlm_config_exit(void);
int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
int *count_out);
int dlm_comm_seq(int nodeid, uint32_t *seq);
-int dlm_comm_mark(int nodeid, unsigned int *mark);
+void dlm_comm_mark(int nodeid, unsigned int *mark);
int dlm_our_nodeid(void);
int dlm_our_addr(struct sockaddr_storage *addr, int num);
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 5050fe05769b..79f56f16bc2c 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -65,40 +65,6 @@
#define MAX_SEND_MSG_COUNT 25
#define DLM_SHUTDOWN_WAIT_TIMEOUT msecs_to_jiffies(10000)
-struct cbuf {
- unsigned int base;
- unsigned int len;
- unsigned int mask;
-};
-
-static void cbuf_add(struct cbuf *cb, int n)
-{
- cb->len += n;
-}
-
-static int cbuf_data(struct cbuf *cb)
-{
- return ((cb->base + cb->len) & cb->mask);
-}
-
-static void cbuf_init(struct cbuf *cb, int size)
-{
- cb->base = cb->len = 0;
- cb->mask = size-1;
-}
-
-static void cbuf_eat(struct cbuf *cb, int n)
-{
- cb->len -= n;
- cb->base += n;
- cb->base &= cb->mask;
-}
-
-static bool cbuf_empty(struct cbuf *cb)
-{
- return cb->len == 0;
-}
-
struct connection {
struct socket *sock; /* NULL if not connected */
uint32_t nodeid; /* So we know who we are in the list */
@@ -117,8 +83,6 @@ struct connection {
int (*rx_action) (struct connection *); /* What to do when active */
void (*connect_action) (struct connection *); /* What to do to connect */
void (*shutdown_action)(struct connection *con); /* What to do to shutdown */
- struct page *rx_page;
- struct cbuf cb;
int retries;
#define MAX_CONNECT_RETRIES 3
struct hlist_node list;
@@ -126,6 +90,10 @@ struct connection {
struct work_struct rwork; /* Receive workqueue */
struct work_struct swork; /* Send workqueue */
wait_queue_head_t shutdown_wait; /* wait for graceful shutdown */
+ unsigned char *rx_buf;
+ int rx_buflen;
+ int rx_leftover;
+ struct rcu_head rcu;
};
#define sock2con(x) ((struct connection *)(x)->sk_user_data)
@@ -167,8 +135,8 @@ static struct workqueue_struct *recv_workqueue;
static struct workqueue_struct *send_workqueue;
static struct hlist_head connection_hash[CONN_HASH_SIZE];
-static DEFINE_MUTEX(connections_lock);
-static struct kmem_cache *con_cache;
+static DEFINE_SPINLOCK(connections_lock);
+DEFINE_STATIC_SRCU(connections_srcu);
static void process_recv_sockets(struct work_struct *work);
static void process_send_sockets(struct work_struct *work);
@@ -184,15 +152,20 @@ static inline int nodeid_hash(int nodeid)
static struct connection *__find_con(int nodeid)
{
- int r;
+ int r, idx;
struct connection *con;
r = nodeid_hash(nodeid);
- hlist_for_each_entry(con, &connection_hash[r], list) {
- if (con->nodeid == nodeid)
+ idx = srcu_read_lock(&connections_srcu);
+ hlist_for_each_entry_rcu(con, &connection_hash[r], list) {
+ if (con->nodeid == nodeid) {
+ srcu_read_unlock(&connections_srcu, idx);
return con;
+ }
}
+ srcu_read_unlock(&connections_srcu, idx);
+
return NULL;
}
@@ -200,21 +173,25 @@ static struct connection *__find_con(int nodeid)
* If 'allocation' is zero then we don't attempt to create a new
* connection structure for this node.
*/
-static struct connection *__nodeid2con(int nodeid, gfp_t alloc)
+static struct connection *nodeid2con(int nodeid, gfp_t alloc)
{
- struct connection *con = NULL;
+ struct connection *con, *tmp;
int r;
con = __find_con(nodeid);
if (con || !alloc)
return con;
- con = kmem_cache_zalloc(con_cache, alloc);
+ con = kzalloc(sizeof(*con), alloc);
if (!con)
return NULL;
- r = nodeid_hash(nodeid);
- hlist_add_head(&con->list, &connection_hash[r]);
+ con->rx_buflen = dlm_config.ci_buffer_size;
+ con->rx_buf = kmalloc(con->rx_buflen, GFP_NOFS);
+ if (!con->rx_buf) {
+ kfree(con);
+ return NULL;
+ }
con->nodeid = nodeid;
mutex_init(&con->sock_mutex);
@@ -233,31 +210,41 @@ static struct connection *__nodeid2con(int nodeid, gfp_t alloc)
con->rx_action = zerocon->rx_action;
}
+ r = nodeid_hash(nodeid);
+
+ spin_lock(&connections_lock);
+ /* Because multiple workqueues/threads calls this function it can
+ * race on multiple cpu's. Instead of locking hot path __find_con()
+ * we just check in rare cases of recently added nodes again
+ * under protection of connections_lock. If this is the case we
+ * abort our connection creation and return the existing connection.
+ */
+ tmp = __find_con(nodeid);
+ if (tmp) {
+ spin_unlock(&connections_lock);
+ kfree(con->rx_buf);
+ kfree(con);
+ return tmp;
+ }
+
+ hlist_add_head_rcu(&con->list, &connection_hash[r]);
+ spin_unlock(&connections_lock);
+
return con;
}
/* Loop round all connections */
static void foreach_conn(void (*conn_func)(struct connection *c))
{
- int i;
- struct hlist_node *n;
+ int i, idx;
struct connection *con;
+ idx = srcu_read_lock(&connections_srcu);
for (i = 0; i < CONN_HASH_SIZE; i++) {
- hlist_for_each_entry_safe(con, n, &connection_hash[i], list)
+ hlist_for_each_entry_rcu(con, &connection_hash[i], list)
conn_func(con);
}
-}
-
-static struct connection *nodeid2con(int nodeid, gfp_t allocation)
-{
- struct connection *con;
-
- mutex_lock(&connections_lock);
- con = __nodeid2con(nodeid, allocation);
- mutex_unlock(&connections_lock);
-
- return con;
+ srcu_read_unlock(&connections_srcu, idx);
}
static struct dlm_node_addr *find_node_addr(int nodeid)
@@ -614,11 +601,8 @@ static void close_connection(struct connection *con, bool and_other,
/* Will only re-enter once. */
close_connection(con->othercon, false, true, true);
}
- if (con->rx_page) {
- __free_page(con->rx_page);
- con->rx_page = NULL;
- }
+ con->rx_leftover = 0;
con->retries = 0;
mutex_unlock(&con->sock_mutex);
clear_bit(CF_CLOSING, &con->flags);
@@ -672,16 +656,33 @@ static void dlm_tcp_shutdown(struct connection *con)
shutdown_connection(con);
}
+static int con_realloc_receive_buf(struct connection *con, int newlen)
+{
+ unsigned char *newbuf;
+
+ newbuf = kmalloc(newlen, GFP_NOFS);
+ if (!newbuf)
+ return -ENOMEM;
+
+ /* copy any leftover from last receive */
+ if (con->rx_leftover)
+ memmove(newbuf, con->rx_buf, con->rx_leftover);
+
+ /* swap to new buffer space */
+ kfree(con->rx_buf);
+ con->rx_buflen = newlen;
+ con->rx_buf = newbuf;
+
+ return 0;
+}
+
/* Data received from remote end */
static int receive_from_sock(struct connection *con)
{
- int ret = 0;
- struct msghdr msg = {};
- struct kvec iov[2];
- unsigned len;
- int r;
int call_again_soon = 0;
- int nvec;
+ struct msghdr msg;
+ struct kvec iov;
+ int ret, buflen;
mutex_lock(&con->sock_mutex);
@@ -689,71 +690,55 @@ static int receive_from_sock(struct connection *con)
ret = -EAGAIN;
goto out_close;
}
+
if (con->nodeid == 0) {
ret = -EINVAL;
goto out_close;
}
- if (con->rx_page == NULL) {
- /*
- * This doesn't need to be atomic, but I think it should
- * improve performance if it is.
- */
- con->rx_page = alloc_page(GFP_ATOMIC);
- if (con->rx_page == NULL)
+ /* realloc if we get new buffer size to read out */
+ buflen = dlm_config.ci_buffer_size;
+ if (con->rx_buflen != buflen && con->rx_leftover <= buflen) {
+ ret = con_realloc_receive_buf(con, buflen);
+ if (ret < 0)
goto out_resched;
- cbuf_init(&con->cb, PAGE_SIZE);
}
- /*
- * iov[0] is the bit of the circular buffer between the current end
- * point (cb.base + cb.len) and the end of the buffer.
- */
- iov[0].iov_len = con->cb.base - cbuf_data(&con->cb);
- iov[0].iov_base = page_address(con->rx_page) + cbuf_data(&con->cb);
- iov[1].iov_len = 0;
- nvec = 1;
-
- /*
- * iov[1] is the bit of the circular buffer between the start of the
- * buffer and the start of the currently used section (cb.base)
+ /* calculate new buffer parameter regarding last receive and
+ * possible leftover bytes
*/
- if (cbuf_data(&con->cb) >= con->cb.base) {
- iov[0].iov_len = PAGE_SIZE - cbuf_data(&con->cb);
- iov[1].iov_len = con->cb.base;
- iov[1].iov_base = page_address(con->rx_page);
- nvec = 2;
- }
- len = iov[0].iov_len + iov[1].iov_len;
- iov_iter_kvec(&msg.msg_iter, READ, iov, nvec, len);
+ iov.iov_base = con->rx_buf + con->rx_leftover;
+ iov.iov_len = con->rx_buflen - con->rx_leftover;
- r = ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT | MSG_NOSIGNAL);
+ memset(&msg, 0, sizeof(msg));
+ msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL;
+ ret = kernel_recvmsg(con->sock, &msg, &iov, 1, iov.iov_len,
+ msg.msg_flags);
if (ret <= 0)
goto out_close;
- else if (ret == len)
+ else if (ret == iov.iov_len)
call_again_soon = 1;
- cbuf_add(&con->cb, ret);
- ret = dlm_process_incoming_buffer(con->nodeid,
- page_address(con->rx_page),
- con->cb.base, con->cb.len,
- PAGE_SIZE);
- if (ret < 0) {
- log_print("lowcomms err %d: addr=%p, base=%u, len=%u, read=%d",
- ret, page_address(con->rx_page), con->cb.base,
- con->cb.len, r);
- cbuf_eat(&con->cb, r);
- } else {
- cbuf_eat(&con->cb, ret);
- }
+ /* new buflen according readed bytes and leftover from last receive */
+ buflen = ret + con->rx_leftover;
+ ret = dlm_process_incoming_buffer(con->nodeid, con->rx_buf, buflen);
+ if (ret < 0)
+ goto out_close;
- if (cbuf_empty(&con->cb) && !call_again_soon) {
- __free_page(con->rx_page);
- con->rx_page = NULL;
+ /* calculate leftover bytes from process and put it into begin of
+ * the receive buffer, so next receive we have the full message
+ * at the start address of the receive buffer.
+ */
+ con->rx_leftover = buflen - ret;
+ if (con->rx_leftover) {
+ memmove(con->rx_buf, con->rx_buf + ret,
+ con->rx_leftover);
+ call_again_soon = true;
}
if (call_again_soon)
goto out_resched;
+
mutex_unlock(&con->sock_mutex);
return 0;
@@ -791,13 +776,11 @@ static int accept_from_sock(struct connection *con)
int nodeid;
struct connection *newcon;
struct connection *addcon;
+ unsigned int mark;
- mutex_lock(&connections_lock);
if (!dlm_allow_conn) {
- mutex_unlock(&connections_lock);
return -1;
}
- mutex_unlock(&connections_lock);
mutex_lock_nested(&con->sock_mutex, 0);
@@ -830,6 +813,9 @@ static int accept_from_sock(struct connection *con)
return -1;
}
+ dlm_comm_mark(nodeid, &mark);
+ sock_set_mark(newsock->sk, mark);
+
log_print("got connection from %d", nodeid);
/* Check to see if we already have a connection to this node. This
@@ -847,13 +833,24 @@ static int accept_from_sock(struct connection *con)
struct connection *othercon = newcon->othercon;
if (!othercon) {
- othercon = kmem_cache_zalloc(con_cache, GFP_NOFS);
+ othercon = kzalloc(sizeof(*othercon), GFP_NOFS);
if (!othercon) {
log_print("failed to allocate incoming socket");
mutex_unlock(&newcon->sock_mutex);
result = -ENOMEM;
goto accept_err;
}
+
+ othercon->rx_buflen = dlm_config.ci_buffer_size;
+ othercon->rx_buf = kmalloc(othercon->rx_buflen, GFP_NOFS);
+ if (!othercon->rx_buf) {
+ mutex_unlock(&newcon->sock_mutex);
+ kfree(othercon);
+ log_print("failed to allocate incoming socket receive buffer");
+ result = -ENOMEM;
+ goto accept_err;
+ }
+
othercon->nodeid = nodeid;
othercon->rx_action = receive_from_sock;
mutex_init(&othercon->sock_mutex);
@@ -975,6 +972,8 @@ static void sctp_connect_to_sock(struct connection *con)
return;
}
+ dlm_comm_mark(con->nodeid, &mark);
+
mutex_lock(&con->sock_mutex);
/* Some odd races can cause double-connects, ignore them */
@@ -999,11 +998,6 @@ static void sctp_connect_to_sock(struct connection *con)
if (result < 0)
goto socket_err;
- /* set skb mark */
- result = dlm_comm_mark(con->nodeid, &mark);
- if (result < 0)
- goto bind_err;
-
sock_set_mark(sock->sk, mark);
con->rx_action = receive_from_sock;
@@ -1076,6 +1070,8 @@ static void tcp_connect_to_sock(struct connection *con)
return;
}
+ dlm_comm_mark(con->nodeid, &mark);
+
mutex_lock(&con->sock_mutex);
if (con->retries++ > MAX_CONNECT_RETRIES)
goto out;
@@ -1090,11 +1086,6 @@ static void tcp_connect_to_sock(struct connection *con)
if (result < 0)
goto out_err;
- /* set skb mark */
- result = dlm_comm_mark(con->nodeid, &mark);
- if (result < 0)
- goto out_err;
-
sock_set_mark(sock->sk, mark);
memset(&saddr, 0, sizeof(saddr));
@@ -1238,6 +1229,14 @@ static void init_local(void)
}
}
+static void deinit_local(void)
+{
+ int i;
+
+ for (i = 0; i < dlm_local_count; i++)
+ kfree(dlm_local_addr[i]);
+}
+
/* Initialise SCTP socket and bind to all interfaces */
static int sctp_listen_for_all(void)
{
@@ -1546,13 +1545,6 @@ static void process_send_sockets(struct work_struct *work)
send_to_sock(con);
}
-
-/* Discard all entries on the write queues */
-static void clean_writequeues(void)
-{
- foreach_conn(clean_one_writequeue);
-}
-
static void work_stop(void)
{
if (recv_workqueue)
@@ -1608,26 +1600,34 @@ static void shutdown_conn(struct connection *con)
con->shutdown_action(con);
}
+static void connection_release(struct rcu_head *rcu)
+{
+ struct connection *con = container_of(rcu, struct connection, rcu);
+
+ kfree(con->rx_buf);
+ kfree(con);
+}
+
static void free_conn(struct connection *con)
{
close_connection(con, true, true, true);
- if (con->othercon)
- kmem_cache_free(con_cache, con->othercon);
- hlist_del(&con->list);
- kmem_cache_free(con_cache, con);
+ spin_lock(&connections_lock);
+ hlist_del_rcu(&con->list);
+ spin_unlock(&connections_lock);
+ if (con->othercon) {
+ clean_one_writequeue(con->othercon);
+ call_rcu(&con->othercon->rcu, connection_release);
+ }
+ clean_one_writequeue(con);
+ call_rcu(&con->rcu, connection_release);
}
static void work_flush(void)
{
- int ok;
+ int ok, idx;
int i;
- struct hlist_node *n;
struct connection *con;
- if (recv_workqueue)
- flush_workqueue(recv_workqueue);
- if (send_workqueue)
- flush_workqueue(send_workqueue);
do {
ok = 1;
foreach_conn(stop_conn);
@@ -1635,9 +1635,10 @@ static void work_flush(void)
flush_workqueue(recv_workqueue);
if (send_workqueue)
flush_workqueue(send_workqueue);
+ idx = srcu_read_lock(&connections_srcu);
for (i = 0; i < CONN_HASH_SIZE && ok; i++) {
- hlist_for_each_entry_safe(con, n,
- &connection_hash[i], list) {
+ hlist_for_each_entry_rcu(con, &connection_hash[i],
+ list) {
ok &= test_bit(CF_READ_PENDING, &con->flags);
ok &= test_bit(CF_WRITE_PENDING, &con->flags);
if (con->othercon) {
@@ -1648,6 +1649,7 @@ static void work_flush(void)
}
}
}
+ srcu_read_unlock(&connections_srcu, idx);
} while (!ok);
}
@@ -1656,16 +1658,18 @@ void dlm_lowcomms_stop(void)
/* Set all the flags to prevent any
socket activity.
*/
- mutex_lock(&connections_lock);
dlm_allow_conn = 0;
- mutex_unlock(&connections_lock);
+
+ if (recv_workqueue)
+ flush_workqueue(recv_workqueue);
+ if (send_workqueue)
+ flush_workqueue(send_workqueue);
+
foreach_conn(shutdown_conn);
work_flush();
- clean_writequeues();
foreach_conn(free_conn);
work_stop();
-
- kmem_cache_destroy(con_cache);
+ deinit_local();
}
int dlm_lowcomms_start(void)
@@ -1684,16 +1688,9 @@ int dlm_lowcomms_start(void)
goto fail;
}
- error = -ENOMEM;
- con_cache = kmem_cache_create("dlm_conn", sizeof(struct connection),
- __alignof__(struct connection), 0,
- NULL);
- if (!con_cache)
- goto fail;
-
error = work_start();
if (error)
- goto fail_destroy;
+ goto fail;
dlm_allow_conn = 1;
@@ -1710,12 +1707,8 @@ int dlm_lowcomms_start(void)
fail_unlisten:
dlm_allow_conn = 0;
con = nodeid2con(0,0);
- if (con) {
- close_connection(con, false, true, true);
- kmem_cache_free(con_cache, con);
- }
-fail_destroy:
- kmem_cache_destroy(con_cache);
+ if (con)
+ free_conn(con);
fail:
return error;
}
diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c
index 921322d133e3..fde3a6afe4be 100644
--- a/fs/dlm/midcomms.c
+++ b/fs/dlm/midcomms.c
@@ -22,114 +22,84 @@
* into packets and sends them to the comms layer.
*/
+#include <asm/unaligned.h>
+
#include "dlm_internal.h"
#include "lowcomms.h"
#include "config.h"
#include "lock.h"
#include "midcomms.h"
-
-static void copy_from_cb(void *dst, const void *base, unsigned offset,
- unsigned len, unsigned limit)
-{
- unsigned copy = len;
-
- if ((copy + offset) > limit)
- copy = limit - offset;
- memcpy(dst, base + offset, copy);
- len -= copy;
- if (len)
- memcpy(dst + copy, base, len);
-}
-
/*
* Called from the low-level comms layer to process a buffer of
* commands.
- *
- * Only complete messages are processed here, any "spare" bytes from
- * the end of a buffer are saved and tacked onto the front of the next
- * message that comes in. I doubt this will happen very often but we
- * need to be able to cope with it and I don't want the task to be waiting
- * for packets to come in when there is useful work to be done.
*/
-int dlm_process_incoming_buffer(int nodeid, const void *base,
- unsigned offset, unsigned len, unsigned limit)
+int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int len)
{
- union {
- unsigned char __buf[DLM_INBUF_LEN];
- /* this is to force proper alignment on some arches */
- union dlm_packet p;
- } __tmp;
- union dlm_packet *p = &__tmp.p;
- int ret = 0;
- int err = 0;
+ const unsigned char *ptr = buf;
+ const struct dlm_header *hd;
uint16_t msglen;
- uint32_t lockspace;
-
- while (len > sizeof(struct dlm_header)) {
-
- /* Copy just the header to check the total length. The
- message may wrap around the end of the buffer back to the
- start, so we need to use a temp buffer and copy_from_cb. */
-
- copy_from_cb(p, base, offset, sizeof(struct dlm_header),
- limit);
-
- msglen = le16_to_cpu(p->header.h_length);
- lockspace = p->header.h_lockspace;
+ int ret = 0;
- err = -EINVAL;
- if (msglen < sizeof(struct dlm_header))
- break;
- if (p->header.h_cmd == DLM_MSG) {
- if (msglen < sizeof(struct dlm_message))
- break;
- } else {
- if (msglen < sizeof(struct dlm_rcom))
- break;
- }
- err = -E2BIG;
- if (msglen > dlm_config.ci_buffer_size) {
- log_print("message size %d from %d too big, buf len %d",
- msglen, nodeid, len);
- break;
+ while (len >= sizeof(struct dlm_header)) {
+ hd = (struct dlm_header *)ptr;
+
+ /* no message should be more than this otherwise we
+ * cannot deliver this message to upper layers
+ */
+ msglen = get_unaligned_le16(&hd->h_length);
+ if (msglen > DEFAULT_BUFFER_SIZE) {
+ log_print("received invalid length header: %u, will abort message parsing",
+ msglen);
+ return -EBADMSG;
}
- err = 0;
-
- /* If only part of the full message is contained in this
- buffer, then do nothing and wait for lowcomms to call
- us again later with more data. We return 0 meaning
- we've consumed none of the input buffer. */
+ /* caller will take care that leftover
+ * will be parsed next call with more data
+ */
if (msglen > len)
break;
- /* Allocate a larger temp buffer if the full message won't fit
- in the buffer on the stack (which should work for most
- ordinary messages). */
-
- if (msglen > sizeof(__tmp) && p == &__tmp.p) {
- p = kmalloc(dlm_config.ci_buffer_size, GFP_NOFS);
- if (p == NULL)
- return ret;
- }
+ switch (hd->h_cmd) {
+ case DLM_MSG:
+ if (msglen < sizeof(struct dlm_message)) {
+ log_print("dlm msg too small: %u, will skip this message",
+ msglen);
+ goto skip;
+ }
- copy_from_cb(p, base, offset, msglen, limit);
+ break;
+ case DLM_RCOM:
+ if (msglen < sizeof(struct dlm_rcom)) {
+ log_print("dlm rcom msg too small: %u, will skip this message",
+ msglen);
+ goto skip;
+ }
- BUG_ON(lockspace != p->header.h_lockspace);
+ break;
+ default:
+ log_print("unsupported h_cmd received: %u, will skip this message",
+ hd->h_cmd);
+ goto skip;
+ }
+ /* for aligned memory access, we just copy current message
+ * to begin of the buffer which contains already parsed buffer
+ * data and should provide align access for upper layers
+ * because the start address of the buffer has a aligned
+ * address. This memmove can be removed when the upperlayer
+ * is capable of unaligned memory access.
+ */
+ memmove(buf, ptr, msglen);
+ dlm_receive_buffer((union dlm_packet *)buf, nodeid);
+
+skip:
ret += msglen;
- offset += msglen;
- offset &= (limit - 1);
len -= msglen;
-
- dlm_receive_buffer(p, nodeid);
+ ptr += msglen;
}
- if (p != &__tmp.p)
- kfree(p);
-
- return err ? err : ret;
+ return ret;
}
diff --git a/fs/dlm/midcomms.h b/fs/dlm/midcomms.h
index 2e122e81c8d0..61e90a921849 100644
--- a/fs/dlm/midcomms.h
+++ b/fs/dlm/midcomms.h
@@ -12,8 +12,7 @@
#ifndef __MIDCOMMS_DOT_H__
#define __MIDCOMMS_DOT_H__
-int dlm_process_incoming_buffer(int nodeid, const void *base, unsigned offset,
- unsigned len, unsigned limit);
+int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int buflen);
#endif /* __MIDCOMMS_DOT_H__ */