sockets: Move packet queue handling into sk-queue.h

Easier to read.

[ xemul: There's a silent change in how sk buffer is read in -- before
  the patch there was a static buffer for data, now this thing is
  xrealloc-ed ]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile

@@ -39,6 +39,7 @@ OBJS		+= rbtree.o
 OBJS		+= log.o
 OBJS		+= libnetlink.o
 OBJS		+= sockets.o
+OBJS		+= sk-queue.o
 OBJS		+= files.o
 OBJS		+= pipes.o
 OBJS		+= file-ids.o

include/sk-queue.h

+#ifndef SK_QUEUE_H__
+#define SK_QUEUE_H__
+
+#include "types.h"
+#include "list.h"
+#include "crtools.h"
+#include "image.h"
+
+struct sk_packet {
+	struct list_head	list;
+	struct sk_packet_entry	entry;
+	off_t			img_off;
+};
+
+extern int read_sk_queues(void);
+extern int dump_sk_queue(int sock_fd, int sock_id);
+extern void show_sk_queues(int fd, struct cr_options *o);
+extern int restore_sk_queue(int fd, unsigned int peer_id);
+
+#endif /* SK_QUEUE_H__ */

sk-queue.c

+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <limits.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/sendfile.h>
+
+#include "types.h"
+#include "list.h"
+#include "image.h"
+#include "crtools.h"
+#include "util.h"
+#include "util-net.h"
+
+#include "sk-queue.h"
+
+static LIST_HEAD(packets_list);
+
+int read_sk_queues(void)
+{
+	struct sk_packet *pkt;
+	int ret, fd;
+
+	pr_info("Trying to read socket queues image\n");
+
+	fd = open_image_ro(CR_FD_SK_QUEUES);
+	if (fd < 0)
+		return -1;
+
+	while (1) {
+		struct sk_packet_entry tmp;
+
+		pkt = xmalloc(sizeof(*pkt));
+		if (!pkt) {
+			pr_err("Failed to allocate packet header\n");
+			return -ENOMEM;
+		}
+		ret = read_img_eof(fd, &pkt->entry);
+		if (ret <= 0)
+			break;
+
+		pkt->img_off = lseek(fd, 0, SEEK_CUR);
+		/*
+		 * NOTE: packet must be added to the tail. Otherwise sequence
+		 * will be broken.
+		 */
+		list_add_tail(&pkt->list, &packets_list);
+		lseek(fd, pkt->entry.length, SEEK_CUR);
+	}
+	close(fd);
+	xfree(pkt);
+
+	return ret;
+}
+
+int dump_sk_queue(int sock_fd, int sock_id)
+{
+	struct sk_packet_entry *pe;
+	unsigned long size;
+	socklen_t tmp;
+	int ret, orig_peek_off;
+
+	/*
+	 * Save original peek offset.
+	 */
+	tmp = sizeof(orig_peek_off);
+	ret = getsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &orig_peek_off, &tmp);
+	if (ret < 0) {
+		pr_perror("getsockopt failed\n");
+		return ret;
+	}
+	/*
+	 * Discover max DGRAM size
+	 */
+	tmp = sizeof(size);
+	ret = getsockopt(sock_fd, SOL_SOCKET, SO_SNDBUF, &size, &tmp);
+	if (ret < 0) {
+		pr_perror("getsockopt failed\n");
+		return ret;
+	}
+
+	/* Note: 32 bytes will be used by kernel for protocol header. */
+	size -= 32;
+	/*
+	 * Try to alloc buffer for max supported DGRAM + our header.
+	 * Note: STREAM queue will be written by chunks of this size.
+	 */
+	pe = xmalloc(size + sizeof(struct sk_packet_entry));
+	if (!pe)
+		return -ENOMEM;
+
+	/*
+	 * Enable peek offset incrementation.
+	 */
+	ret = setsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &ret, sizeof(int));
+	if (ret < 0) {
+		pr_perror("setsockopt fail\n");
+		goto err_brk;
+	}
+
+	pe->id_for = sock_id;
+
+	while (1) {
+		struct iovec iov = {
+			.iov_base	= pe->data,
+			.iov_len	= size,
+		};
+		struct msghdr msg = {
+			.msg_iov	= &iov,
+			.msg_iovlen	= 1,
+		};
+
+		ret = pe->length = recvmsg(sock_fd, &msg, MSG_DONTWAIT | MSG_PEEK);
+		if (ret < 0) {
+			if (ret == -EAGAIN)
+				break; /* we're done */
+			pr_perror("sys_recvmsg fail: error\n");
+			goto err_set_sock;
+		}
+		if (msg.msg_flags & MSG_TRUNC) {
+			/*
+			 * DGRAM thuncated. This should not happen. But we have
+			 * to check...
+			 */
+			pr_err("sys_recvmsg failed: truncated\n");
+			ret = -E2BIG;
+			goto err_set_sock;
+		}
+		ret = write_img_buf(fdset_fd(glob_fdset, CR_FD_SK_QUEUES),
+				pe, sizeof(pe) + pe->length);
+		if (ret < 0) {
+			ret = -EIO;
+			goto err_set_sock;
+		}
+	}
+	ret = 0;
+
+err_set_sock:
+	/*
+	 * Restore original peek offset.
+	 */
+	ret = setsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &orig_peek_off, sizeof(int));
+	if (ret < 0)
+		pr_perror("setsockopt failed on restore\n");
+err_brk:
+	xfree(pe);
+	return ret;
+}
+
+void show_sk_queues(int fd, struct cr_options *o)
+{
+	struct sk_packet_entry pe;
+	char *buf = NULL, *p;
+	int ret;
+
+	pr_img_head(CR_FD_SK_QUEUES);
+	while (1) {
+		ret = read_img_eof(fd, &pe);
+		if (ret <= 0)
+			break;
+		p = xrealloc(buf, pe.length);
+		if (!p)
+			break;
+		buf = p;
+		pr_info("pkt for %u length %u bytes\n",
+				pe.id_for, pe.length);
+
+		ret = read_img_buf(fd, (unsigned char *)buf, pe.length);
+		if (ret < 0)
+			break;
+
+		print_data(0, (unsigned char *)buf, pe.length);
+	}
+	xfree(buf);
+	pr_img_tail(CR_FD_SK_QUEUES);
+}
+
+int restore_sk_queue(int fd, unsigned int peer_id)
+{
+	struct sk_packet *pkt, *tmp;
+	int ret, img_fd;
+
+	pr_info("Trying to restore recv queue for %u\n", peer_id);
+
+	img_fd = open_image_ro(CR_FD_SK_QUEUES);
+	if (img_fd < 0)
+		return -1;
+
+	list_for_each_entry_safe(pkt, tmp, &packets_list, list) {
+		struct sk_packet_entry *entry = &pkt->entry;
+
+		if (entry->id_for != peer_id)
+			continue;
+
+		pr_info("\tRestoring %d-bytes skb for %u\n",
+				entry->length, peer_id);
+
+		ret = sendfile(fd, img_fd, &pkt->img_off, entry->length);
+		if (ret < 0) {
+			pr_perror("Failed to sendfile packet");
+			return -1;
+		}
+		if (ret != entry->length) {
+			pr_err("Restored skb trimmed to %d/%d\n",
+					ret, entry->length);
+			return -1;
+		}
+		list_del(&pkt->list);
+		xfree(pkt);
+	}
+
+	close(img_fd);
+	return 0;
+}

sockets.c

@@ -16,6 +16,7 @@
 #include "types.h"
 #include "libnetlink.h"
 #include "sockets.h"
+#include "sk-queue.h"
 #include "unix_diag.h"
 #include "image.h"
 #include "crtools.h"
@@ -80,100 +81,6 @@ struct inet_sk_desc {
 	unsigned int		dst_addr[4];
 };
 
-static int dump_socket_queue(int sock_fd, int sock_id)
-{
-	struct sk_packet_entry *pe;
-	unsigned long size;
-	socklen_t tmp;
-	int ret, orig_peek_off;
-
-	/*
-	 * Save original peek offset. 
-	 */
-	tmp = sizeof(orig_peek_off);
-	ret = getsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &orig_peek_off, &tmp);
-	if (ret < 0) {
-		pr_perror("getsockopt failed\n");
-		return ret;
-	}
-	/*
-	 * Discover max DGRAM size
-	 */
-	tmp = sizeof(size);
-	ret = getsockopt(sock_fd, SOL_SOCKET, SO_SNDBUF, &size, &tmp);
-	if (ret < 0) {
-		pr_perror("getsockopt failed\n");
-		return ret;
-	}
-
-	/* Note: 32 bytes will be used by kernel for protocol header. */
-	size -= 32;
-	/*
-	 * Try to alloc buffer for max supported DGRAM + our header.
-	 * Note: STREAM queue will be written by chunks of this size.
-	 */
-	pe = xmalloc(size + sizeof(struct sk_packet_entry));
-	if (!pe)
-		return -ENOMEM;
-
-	/*
-	 * Enable peek offset incrementation.
-	 */
-	ret = setsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &ret, sizeof(int));
-	if (ret < 0) {
-		pr_perror("setsockopt fail\n");
-		goto err_brk;
-	}
-
-	pe->id_for = sock_id;
-
-	while (1) {
-		struct iovec iov = {
-			.iov_base	= pe->data,
-			.iov_len	= size,
-		};
-		struct msghdr msg = {
-			.msg_iov	= &iov,
-			.msg_iovlen	= 1,
-		};
-
-		ret = pe->length = recvmsg(sock_fd, &msg, MSG_DONTWAIT | MSG_PEEK);
-		if (ret < 0) {
-			if (ret == -EAGAIN)
-				break; /* we're done */
-			pr_perror("sys_recvmsg fail: error\n");
-			goto err_set_sock;
-		}
-		if (msg.msg_flags & MSG_TRUNC) {
-			/*
-			 * DGRAM thuncated. This should not happen. But we have
-			 * to check...
-			 */
-			pr_err("sys_recvmsg failed: truncated\n");
-			ret = -E2BIG;
-			goto err_set_sock;
-		}
-		ret = write_img_buf(fdset_fd(glob_fdset, CR_FD_SK_QUEUES),
-				pe, sizeof(pe) + pe->length);
-		if (ret < 0) {
-			ret = -EIO;
-			goto err_set_sock;
-		}
-	}
-	ret = 0;
-
-err_set_sock:
-	/*
-	 * Restore original peek offset. 
-	 */
-	ret = setsockopt(sock_fd, SOL_SOCKET, SO_PEEK_OFF, &orig_peek_off, sizeof(int));
-	if (ret < 0)
-		pr_perror("setsockopt failed on restore\n");
-err_brk:
-	xfree(pe);
-	return ret;
-}
-
 #define SK_HASH_SIZE		32
 #define SK_HASH_LINK(head, key, elem)					\
 	do {								\
@@ -465,7 +372,7 @@ static int dump_one_unix(const struct socket_desc *_sk, struct fd_parms *p,
 
 	if (sk->rqlen != 0 && !(sk->type == SOCK_STREAM &&
 				sk->state == TCP_LISTEN))
-		if (dump_socket_queue(lfd, ue.id))
+		if (dump_sk_queue(lfd, ue.id))
 			goto err;
 
 	pr_info("Dumping unix socket at %d\n", p->fd);
@@ -938,89 +845,6 @@ static struct unix_sk_info *find_unix_sk(int id)
 	return NULL;
 }
 
-struct sk_packet {
-	struct list_head list;
-	struct sk_packet_entry entry;
-	off_t img_off;
-};
-
-static LIST_HEAD(packets_list);
-
-static int read_sockets_queues(void)
-{
-	struct sk_packet *pkt;
-	int ret, fd;
-
-	pr_info("Trying to read socket queues image\n");
-
-	fd = open_image_ro(CR_FD_SK_QUEUES);
-	if (fd < 0)
-		return -1;
-
-	while (1) {
-		struct sk_packet_entry tmp;
-
-		pkt = xmalloc(sizeof(*pkt));
-		if (!pkt) {
-			pr_err("Failed to allocate packet header\n");
-			return -ENOMEM;
-		}
-		ret = read_img_eof(fd, &pkt->entry);
-		if (ret <= 0)
-			break;
-
-		pkt->img_off = lseek(fd, 0, SEEK_CUR);
-		/*
-		 * NOTE: packet must be added to the tail. Otherwise sequence
-		 * will be broken.
-		 */
-		list_add_tail(&pkt->list, &packets_list);
-		lseek(fd, pkt->entry.length, SEEK_CUR);
-	}
-	close(fd);
-	xfree(pkt);
-
-	return ret;
-}
-
-static int restore_socket_queue(int fd, unsigned int peer_id)
-{
-	struct sk_packet *pkt, *tmp;
-	int ret, img_fd;
-
-	pr_info("Trying to restore recv queue for %u\n", peer_id);
-
-	img_fd = open_image_ro(CR_FD_SK_QUEUES);
-	if (img_fd < 0)
-		return -1;
-
-	list_for_each_entry_safe(pkt, tmp, &packets_list, list) {
-		struct sk_packet_entry *entry = &pkt->entry;
-
-		if (entry->id_for != peer_id)
-			continue;
-
-		pr_info("\tRestoring %d-bytes skb for %u\n",
-				entry->length, peer_id);
-
-		ret = sendfile(fd, img_fd, &pkt->img_off, entry->length);
-		if (ret < 0) {
-			pr_perror("Failed to sendfile packet");
-			return -1;
-		}
-		if (ret != entry->length) {
-			pr_err("Restored skb trimmed to %d/%d\n",
-					ret, entry->length);
-			return -1;
-		}
-		list_del(&pkt->list);
-		xfree(pkt);
-	}
-
-	close(img_fd);
-	return 0;
-}
-
 struct inet_sk_info {
 	struct inet_sk_entry ie;
 	struct file_desc d;
@@ -1289,29 +1113,6 @@ out:
 	pr_img_tail(CR_FD_UNIXSK);
 }
 
-void show_sk_queues(int fd, struct cr_options *o)
-{
-	struct sk_packet_entry pe;
-	int ret;
-
-	pr_img_head(CR_FD_SK_QUEUES);
-	while (1) {
-		ret = read_img_eof(fd, &pe);
-		if (ret <= 0)
-			break;
-
-		pr_info("pkt for %u length %u bytes\n",
-				pe.id_for, pe.length);
-
-		ret = read_img_buf(fd, (unsigned char *)buf, pe.length);
-		if (ret < 0)
-			break;
-
-		print_data(0, (unsigned char *)buf, pe.length);
-	}
-	pr_img_tail(CR_FD_SK_QUEUES);
-}
-
 struct unix_conn_job {
 	struct unix_sk_info	*sk;
 	struct unix_conn_job	*next;
@@ -1369,7 +1170,7 @@ try_again:
 			return -1;
 		}
 
-		if (restore_socket_queue(fle->fe.fd, peer->ue.id))
+		if (restore_sk_queue(fle->fe.fd, peer->ue.id))
 			return -1;
 
 		if (set_fd_flags(fle->fe.fd, ui->ue.flags))
@@ -1431,9 +1232,9 @@ static int open_unixsk_pair_master(struct unix_sk_info *ui)
 		return -1;
 	}
 
-	if (restore_socket_queue(sk[0], peer->ue.id))
+	if (restore_sk_queue(sk[0], peer->ue.id))
 		return -1;
-	if (restore_socket_queue(sk[1], ui->ue.id))
+	if (restore_sk_queue(sk[1], ui->ue.id))
 		return -1;
 
 	if (set_fd_flags(sk[0], ui->ue.flags))
@@ -1606,7 +1407,7 @@ int collect_unix_sockets(void)
 
 	close(fd);
 
-	return read_sockets_queues();
+	return read_sk_queues();
 }
 
 int resolve_unix_peers(void)