sockets: Remove statfs and 2nd stat from dump process

The statfs is not required, we now check for fd being a socket with S_IFSOCK.
The 2nd stat is just not needed, the caller provides stat info.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-dump.c

@@ -33,6 +33,7 @@
 #include "proc_parse.h"
 #include "parasite.h"
 #include "parasite-syscall.h"
+#include "files.h"
 
 #ifndef CONFIG_X86_64
 # error No x86-32 support yet
@@ -125,16 +126,6 @@ static int collect_fds(pid_t pid, int *fd, int *nr_fd)
 	return 0;
 }
 
-struct fd_parms {
-	unsigned long	fd_name;
-	unsigned long	pos;
-	unsigned int	flags;
-	unsigned int	type;
-	struct stat	stat;
-	u32		id;
-	pid_t		pid;
-};
-
 static int dump_one_reg_file(int lfd, u32 id, const struct fd_parms *p)
 {
 	char fd_str[128];
@@ -360,7 +351,7 @@ static int dump_one_fd(pid_t pid, int fd, int lfd,
 	}
 
 	if (S_ISSOCK(p.stat.st_mode))
-		return dump_socket(pid, fd, cr_fdset, sk_queue);
+		return dump_socket(&p, lfd, cr_fdset, sk_queue);
 
 	if (S_ISCHR(p.stat.st_mode) &&
 	    (major(p.stat.st_rdev) == TTY_MAJOR ||

include/files.h

@@ -7,6 +7,16 @@
 #include "list.h"
 #include "image.h"
 
+struct fd_parms {
+	unsigned long	fd_name;
+	unsigned long	pos;
+	unsigned int	flags;
+	unsigned int	type;
+	struct stat	stat;
+	u32		id;
+	pid_t		pid;
+};
+
 enum fdinfo_states {
 	FD_STATE_PREP,		/* Create unix sockets */
 	FD_STATE_CREATE,	/* Create and send fd */

include/sockets.h

@@ -22,8 +22,9 @@ struct sk_queue {
 };
 
 struct cr_fdset;
-extern int dump_socket(pid_t pid, int fd, const struct cr_fdset *cr_fdset,
-			   struct sk_queue *queue);
+struct fd_parms;
+extern int dump_socket(struct fd_parms *p, int lfd,
+		const struct cr_fdset *cr_fdset, struct sk_queue *queue);
 
 extern int collect_sockets(void);
 extern int prepare_sockets(int pid);

sockets.c

@@ -22,6 +22,7 @@
 #include "crtools.h"
 #include "util.h"
 #include "inet_diag.h"
+#include "files.h"
 
 static char buf[4096];
 
@@ -381,7 +382,7 @@ err:
 	return -1;
 }
 
-int dump_socket(pid_t pid, int fd, const struct cr_fdset *cr_fdset,
+int dump_socket(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset,
 		    struct sk_queue *queue)
 {
 	struct socket_desc *sk;
@@ -389,25 +390,7 @@ int dump_socket(pid_t pid, int fd, const struct cr_fdset *cr_fdset,
 	struct stat st;
 	char path[64];
 
-	/*
-	 * Sockets are tricky, we can't open it but can
-	 * do stats over and check for sokets magic.
-	 */
-	snprintf(buf, sizeof(buf), "/proc/%d/fd/%d", pid, fd);
-	if (statfs(buf, &fst)) {
-		pr_perror("Can't statfs %s", buf);
-		return -1;
-	}
-
-	if (stat(buf, &st)) {
-		pr_perror("Can't stat %s", buf);
-		return -1;
-	}
-
-	if (fst.f_type != SOCKFS_MAGIC)
-		return 1; /* not a socket, proceed with caller error */
-
-	sk = lookup_socket(st.st_ino);
+	sk = lookup_socket(p->stat.st_ino);
 	if (!sk) {
 		pr_err("Uncollected socket %ld\n", st.st_ino);
 		return -1;
@@ -415,9 +398,9 @@ int dump_socket(pid_t pid, int fd, const struct cr_fdset *cr_fdset,
 
 	switch (sk->family) {
 	case AF_UNIX:
-		return dump_one_unix(sk, fd, cr_fdset, queue);
+		return dump_one_unix(sk, p->fd_name, cr_fdset, queue);
 	case AF_INET:
-		return dump_one_inet(sk, fd, cr_fdset, queue);
+		return dump_one_inet(sk, p->fd_name, cr_fdset, queue);
 	default:
 		pr_err("BUG! Unknown socket collected\n");
 		break;