From ec19461cecdac81c48bbbe4783624167754349a2 Mon Sep 17 00:00:00 2001
From: Mike Frysinger <vapier@gentoo.org>
Date: Thu, 8 Mar 2012 17:40:52 -0500
Subject: [PATCH] getdents: rewrite syscall handling completely

The inline asm has many problems, but rather than attempt to fix
them, just use syscall() for everyone.  This allows us to drop the
i386-specific checks and have the tests run on all arches.

Further, add a layer between the kernel and the dirent struct that
the tests uses.  The kernel packs the results, so we need to expand
the raw buffer returned by the kernel into the userland structs we
pass around.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
 testcases/kernel/syscalls/getdents/getdents.h   |   73 +++++++++++++++++------
 testcases/kernel/syscalls/getdents/getdents01.c |   20 +-----
 testcases/kernel/syscalls/getdents/getdents02.c |   27 +--------
 testcases/kernel/syscalls/getdents/getdents03.c |   27 +--------
 testcases/kernel/syscalls/getdents/getdents04.c |   26 +-------
 5 files changed, 67 insertions(+), 106 deletions(-)

diff --git a/testcases/kernel/syscalls/getdents/getdents.h b/testcases/kernel/syscalls/getdents/getdents.h
index 3ab3fd2..a5ddfea 100644
--- a/testcases/kernel/syscalls/getdents/getdents.h
+++ b/testcases/kernel/syscalls/getdents/getdents.h
@@ -23,25 +23,62 @@
 
 #ifndef __GETDENTS_H
 #define __GETDENTS_H	1
+
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
 #include <sys/syscall.h>
 
-#ifdef __i386__
-	#define GETDENTS_ASM() ({ int __rval;				\
-				__asm__ __volatile__("			\
-					movl	%4, %%edx \n		\
-					movl	%3, %%ecx \n		\
-					movl	%2, %%ebx \n		\
-					movl	%1, %%eax \n		\
-					int	$0x80 \n		\
-					movl	%%eax, %0"		\
-				: "=a" (__rval)				\
-				: "a" (cnum), "b" (fd), "c" (dirp), "d" (count)\
-				: "memory"				\
-				);					\
-				__rval;					\
-		    	})
-#else
-	#define GETDENTS_ASM() 0
-#endif /* __i386__ */
+/*
+ * The dirent struct that the C library exports is not the same
+ * as the kernel ABI, so we can't include dirent.h and use the
+ * dirent struct from there.  Further, since the Linux headers
+ * don't export their vision of the struct either, we have to
+ * declare our own here.  Wheeeeee.
+ */
+
+struct linux_dirent {
+	unsigned long   d_ino;
+	unsigned long   d_off;
+	unsigned short  d_reclen;
+	char            d_name[];
+};
+
+static inline int
+getdents(unsigned int fd, struct dirent *dirp, unsigned int count)
+{
+	union {
+		struct linux_dirent *dirp;
+		char *buf;
+	} ptrs;
+	char buf[count];
+	long ret;
+	unsigned int i;
+
+	ptrs.buf = buf;
+	ret = syscall(SYS_getdents, fd, buf, count);
+	if (ret < 0)
+		return ret;
+
+#define kdircpy(field) memcpy(&dirp[i].field, &ptrs.dirp->field, sizeof(dirp[i].field))
+
+	i = 0;
+	while (i < count && i < ret) {
+		unsigned long reclen;
+
+		kdircpy(d_ino);
+		kdircpy(d_reclen);
+		reclen = dirp[i].d_reclen;
+		kdircpy(d_off);
+		strcpy(dirp[i].d_name, ptrs.dirp->d_name);
+
+		ptrs.buf += reclen;
+
+		i += reclen;
+	}
+
+	return ret;
+}
 
 #endif /* getdents.h */
diff --git a/testcases/kernel/syscalls/getdents/getdents01.c b/testcases/kernel/syscalls/getdents/getdents01.c
index 266a9c0..8afb08a 100644
--- a/testcases/kernel/syscalls/getdents/getdents01.c
+++ b/testcases/kernel/syscalls/getdents/getdents01.c
@@ -81,17 +81,6 @@ int main(int ac, char **av)
 	char *dir_name = NULL;
 	struct dirent *dirp;
 
-	/*
-	 * Here's a case where invoking the system call directly
-	 * doesn't seem to work.  getdents.h has an assembly
-	 * macro to do the job.
-	 *
-	 * equivalent to  - getdents(fd, dirp, count);
-	 * if we could call getdents that way.
-	 */
-
-#define getdents(arg1, arg2, arg3) syscall(__NR_getdents, arg1, arg2, arg3)
-
 	if ((msg = parse_opts(ac, av, NULL, NULL)) != NULL)
 		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);
 
@@ -120,17 +109,14 @@ int main(int ac, char **av)
 		rval = getdents(fd, dirp, count);
 		if (rval < 0) {
 
-			rval *= -1;
-			TEST_ERROR_LOG(rval);
+			TEST_ERROR_LOG(errno);
 
-			tst_resm(TFAIL, "%s call failed - errno = %d "
-				 ": %s", TCID, rval, strerror(rval));
+			tst_resm(TFAIL|TERRNO, "getdents failed unexpectedly");
 			continue;
 		}
 
 		if (rval == 0) {
-			tst_resm(TFAIL, "%s call failed - returned "
-				 "end of directory", TCID);
+			tst_resm(TFAIL, "getdents failed - returned end of directory");
 			continue;
 		}
 
diff --git a/testcases/kernel/syscalls/getdents/getdents02.c b/testcases/kernel/syscalls/getdents/getdents02.c
index 46d1133..af826d1 100644
--- a/testcases/kernel/syscalls/getdents/getdents02.c
+++ b/testcases/kernel/syscalls/getdents/getdents02.c
@@ -69,21 +69,12 @@ int TST_TOTAL = 1;
 
 int exp_enos[] = { EBADF, 0 };	/* 0 terminated list of expected errnos */
 
-#ifndef __i386__
-int main(void)
-{
-	tst_brkm(TCONF, NULL, "this test will only run on i386");
-	tst_exit();
-}
-#else
-
 int main(int ac, char **av)
 {
 	int lc;
 	char *msg;
 	int rval, fd;
 	int count;
-	const int cnum = __NR_getdents;
 	size_t size = 0;
 	char *dir_name = NULL;
 	struct dirent *dirp;
@@ -109,25 +100,15 @@ int main(int ac, char **av)
 
 		fd = -5;
 
-		/*
-		 * here's a case where invoking the system call directly
-		 * doesn't seem to work.  getdents.h has an assembly
-		 * macro to do the job.
-		 *
-		 * equivalent to  - getdents(fd, dirp, count);
-		 * if we could call getdents that way.
-		 */
-
-		rval = GETDENTS_ASM();
+		rval = getdents(fd, dirp, count);
 
 		/*
 		 * Hopefully we get an error due to the bad file descriptor.
 		 */
 		if (rval < 0) {
-			rval *= -1;
-			TEST_ERROR_LOG(rval);
+			TEST_ERROR_LOG(errno);
 
-			switch (rval) {
+			switch (errno) {
 			case EBADF:
 				tst_resm(TPASS,
 				    "failed as expected with EBADF");
@@ -170,5 +151,3 @@ void cleanup(void)
 
 	tst_rmdir();
 }
-
-#endif /* __i386__ */
diff --git a/testcases/kernel/syscalls/getdents/getdents03.c b/testcases/kernel/syscalls/getdents/getdents03.c
index 8582346..ffd137f 100644
--- a/testcases/kernel/syscalls/getdents/getdents03.c
+++ b/testcases/kernel/syscalls/getdents/getdents03.c
@@ -72,21 +72,12 @@ int TST_TOTAL = 1;
 
 int exp_enos[] = { EINVAL, 0 };	/* 0 terminated list of expected errnos */
 
-#ifndef __i386__
-int main(void)
-{
-	tst_brkm(TCONF, NULL, "this test will only run on i386");
-	tst_exit();
-}
-#else
-
 int main(int ac, char **av)
 {
 	int lc;
 	char *msg;
 	int rval, fd;
 	int count;
-	const int cnum = __NR_getdents;
 	size_t size = 0;
 	char *dir_name = NULL;
 	struct dirent *dirp;
@@ -114,26 +105,16 @@ int main(int ac, char **av)
 		if ((fd = open(dir_name, O_RDONLY)) == -1)
 			tst_brkm(TBROK, cleanup, "open of directory failed");
 
-		/*
-		 * here's a case where invoking the system call directly
-		 * doesn't seem to work.  getdents.h has an assembly
-		 * macro to do the job.
-		 *
-		 * equivalent to  - getdents(fd, dirp, count)
-		 * if we could call getdents that way.
-		 */
-
-		rval = GETDENTS_ASM();
+		rval = getdents(fd, dirp, count);
 
 		/*
 		 * Hopefully we get an error due to the small buffer.
 		 */
 
 		if (rval < 0) {
-			rval *= -1;
-			TEST_ERROR_LOG(rval);
+			TEST_ERROR_LOG(errno);
 
-			switch (rval) {
+			switch (errno) {
 			case EINVAL:
 				tst_resm(TPASS,
 				    "getdents failed with EINVAL as expected");
@@ -181,5 +162,3 @@ void cleanup(void)
 
 	tst_rmdir();
 }
-
-#endif /* __i386__ */
diff --git a/testcases/kernel/syscalls/getdents/getdents04.c b/testcases/kernel/syscalls/getdents/getdents04.c
index 5dd1634..141d3da 100644
--- a/testcases/kernel/syscalls/getdents/getdents04.c
+++ b/testcases/kernel/syscalls/getdents/getdents04.c
@@ -73,20 +73,11 @@ int TST_TOTAL = 1;
 
 int exp_enos[] = { ENOTDIR, 0 };	/* 0 terminated list of expected errnos */
 
-#ifndef __i386__
-int main(void)
-{
-	tst_brkm(TCONF, NULL, "this test will only run on i386");
-	tst_exit();
-}
-#else
-
 int main(int ac, char **av)
 {
 	int lc;
 	char *msg;
 	int count, rval, fd;
-	const int cnum = 141;
 	size_t size = 0;
 	char *dir_name = NULL;
 	struct dirent *dirp;
@@ -131,15 +122,7 @@ int main(int ac, char **av)
 		if (S_ISDIR(sbuf->st_mode))
 			tst_brkm(TBROK, cleanup, "fd is a directory");
 
-		/*
-		 * here's a case where invoking the system call directly
-		 * doesn't seem to work.  getdents.h has an assembly
-		 * macro to do the job.
-		 *
-		 * equivalent to getdents(fd, dirp, count);
-		 */
-
-		rval = GETDENTS_ASM();
+		rval = getdents(fd, dirp, count);
 
 		/*
 		 * Calling with a non directory file descriptor should give
@@ -147,10 +130,9 @@ int main(int ac, char **av)
 		 */
 
 		if (rval < 0) {
-			rval *= -1;
-			TEST_ERROR_LOG(rval);
+			TEST_ERROR_LOG(errno);
 
-			switch (rval) {
+			switch (errno) {
 			case ENOTDIR:
 				tst_resm(TPASS,
 				    "getdents failed as expected with ENOTDIR");
@@ -198,5 +180,3 @@ void cleanup(void)
 
 	tst_rmdir();
 }
-
-#endif /* __i386__ */
-- 
1.7.8.4