tcp: Switch to use rst memory allocator on repair off

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-restore.c

@@ -2002,6 +2002,9 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 	int siginfo_nr = 0;
 	int *siginfo_priv_nr;
 
+	void *tcp_socks_mem;
+	unsigned long tcp_socks;
+
 
 	unsigned long vdso_rt_vma_size = 0;
 	unsigned long vdso_rt_size = 0;
@@ -2068,12 +2071,18 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 		ret = 0;
 	}
 
+	tcp_socks = rst_mem_cpos();
+	tcp_socks_mem = rst_mem_alloc(rst_tcp_socks_len());
+	if (!tcp_socks_mem)
+		goto err;
+
+	memcpy(tcp_socks_mem, rst_tcp_socks, rst_tcp_socks_len());
+
 	restore_bootstrap_len = restorer_len +
 				restore_task_vma_len +
 				restore_thread_vma_len +
 				SHMEMS_SIZE + TASK_ENTRIES_SIZE +
 				self_vmas_len + vmas_len +
-				rst_tcp_socks_size +
 				rst_mem_len;
 
 	/*
@@ -2172,10 +2181,8 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 		goto err;
 
 	mem += vmas_len;
-	if (rst_tcp_socks_remap(mem))
+	if (rst_mem_remap(mem))
 		goto err;
-	task_args->rst_tcp_socks = mem;
-	task_args->rst_tcp_socks_size = rst_tcp_socks_size;
 
 	task_args->timer_n = posix_timers_nr;
 	task_args->posix_timers = rst_mem_raddr(posix_timers_info_chunk);
@@ -2183,9 +2190,8 @@ static int sigreturn_restore(pid_t pid, CoreEntry *core)
 	task_args->siginfo_nr = siginfo_nr;
 	task_args->siginfo = rst_mem_raddr(siginfo_chunk);
 
-	mem += rst_tcp_socks_size;
-	if (rst_mem_remap(mem))
-		goto err;
+	task_args->tcp_socks_nr = rst_tcp_socks_nr;
+	task_args->tcp_socks = rst_mem_raddr(tcp_socks);
 
 	/*
 	 * Arguments for task restoration.

include/restorer.h

@@ -146,8 +146,8 @@ struct task_restore_core_args {
 	int				nr_rlim;
 	struct rlimit			rlims[RLIM_NLIMITS];
 
-	struct rst_tcp_sock		*rst_tcp_socks;
-	int				rst_tcp_socks_size;
+	struct rst_tcp_sock		*tcp_socks;
+	int				tcp_socks_nr;
 
 	struct vdso_symtable		vdso_sym_rt;		/* runtime vdso symbols */
 	unsigned long			vdso_rt_parked_at;	/* safe place to keep vdso */

include/sk-inet.h

@@ -49,6 +49,14 @@ struct rst_tcp_sock {
 	bool	reuseaddr;
 };
 
+extern struct rst_tcp_sock *rst_tcp_socks;
+extern int rst_tcp_socks_nr;
+
+static inline unsigned long rst_tcp_socks_len(void)
+{
+	return rst_tcp_socks_nr * sizeof(struct rst_tcp_sock);
+}
+
 static inline void tcp_repair_off(int fd)
 {
 	int aux = 0, ret;
@@ -70,9 +78,6 @@ int restore_one_tcp(int sk, struct inet_sk_info *si);
 void show_tcp_stream(int fd);
 
 int check_tcp(void);
-
-extern int rst_tcp_socks_size;
-extern int rst_tcp_socks_remap(void *addr);
 extern int rst_tcp_socks_add(int fd, bool reuseaddr);
 
 #endif /* __CR_SK_INET_H__ */

pie/restorer.c

@@ -384,17 +384,12 @@ static void rst_tcp_repair_off(struct rst_tcp_sock *rts)
 		pr_perror("Failed to restore of SO_REUSEADDR on socket (%d)", ret);
 }
 
-static void rst_tcp_socks_all(struct rst_tcp_sock *arr, int size)
+static void rst_tcp_socks_all(struct task_restore_core_args *ta)
 {
 	int i;
 
-	if (size == 0)
-		return;
-
-	for (i =0; arr[i].sk >= 0; i++)
-		rst_tcp_repair_off(arr + i);
-
-	sys_munmap(arr, size);
+	for (i = 0; i < ta->tcp_socks_nr; i++)
+		rst_tcp_repair_off(&ta->tcp_socks[i]);
 }
 
 static int vma_remap(unsigned long src, unsigned long dst, unsigned long len)
@@ -885,7 +880,7 @@ long __export_restore_task(struct task_restore_core_args *args)
 		goto core_restore_end;
 	}
 
-	rst_tcp_socks_all(args->rst_tcp_socks, args->rst_tcp_socks_size);
+	rst_tcp_socks_all(args);
 
 	/* 
 	 * Writing to last-pid is CAP_SYS_ADMIN protected,

sk-tcp.c

@@ -18,6 +18,7 @@
 #include "netfilter.h"
 #include "image.h"
 #include "namespaces.h"
+#include "xmalloc.h"
 #include "config.h"
 
 #include "protobuf.h"
@@ -555,47 +556,23 @@ err:
  * rst_tcp_socks contains sockets in repair mode,
  * which will be off in restorer before resuming.
  */
-static struct rst_tcp_sock *rst_tcp_socks = NULL;
-static int rst_tcp_socks_num = 0;
-int rst_tcp_socks_size = 0;
+struct rst_tcp_sock *rst_tcp_socks = NULL;
+int rst_tcp_socks_nr = 0;
 
-int rst_tcp_socks_remap(void *addr)
+int rst_tcp_socks_add(int fd, bool reuseaddr)
 {
-	void *ret;
-	if (!rst_tcp_socks) {
-		BUG_ON(rst_tcp_socks_size);
-		return 0;
-	}
-
-	rst_tcp_socks[rst_tcp_socks_num].sk = -1;
+	struct rst_tcp_sock *cur;
 
-	ret = mmap(addr, rst_tcp_socks_size, PROT_READ | PROT_WRITE,
-			MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
-
-	if (ret != addr) {
-		pr_perror("mmap() failed");
+	rst_tcp_socks_nr++;
+	rst_tcp_socks = xrealloc(rst_tcp_socks, rst_tcp_socks_len());
+	if (!rst_tcp_socks)
 		return -1;
-	}
-
-	memcpy(addr, rst_tcp_socks, rst_tcp_socks_size);
-
-	return 0;
-}
-
-int rst_tcp_socks_add(int fd, bool reuseaddr)
-{
-	/* + 2 = ( new one + guard (-1) ) */
-	if ((rst_tcp_socks_num + 2) * sizeof(struct rst_tcp_sock) > rst_tcp_socks_size) {
-		rst_tcp_socks_size += PAGE_SIZE;
-		rst_tcp_socks = xrealloc(rst_tcp_socks, rst_tcp_socks_size);
-		if (rst_tcp_socks == NULL)
-			return -1;
-	}
 
 	pr_debug("Schedule %d socket for repair off\n", fd);
-	rst_tcp_socks[rst_tcp_socks_num].sk = fd;
-	rst_tcp_socks[rst_tcp_socks_num].reuseaddr = reuseaddr;
-	rst_tcp_socks_num++;
+	cur = &rst_tcp_socks[rst_tcp_socks_nr - 1];
+	cur->sk = fd;
+	cur->reuseaddr = reuseaddr;
+
 	return 0;
 }