[PATCH 0/4] xfstests: add deadlock between the AGI and AGF with RENAME_WHITEOUT test

[PATCH 0/4] xfstests: add deadlock between the AGI and AGF with RENAME_WHITEOUT test

[kaixuxia]

Hi all,

There is ABBA deadlock bug between the AGI and AGF when performing
rename() with RENAME_WHITEOUT flag, so add test to check that whether
the rename() call works well. We add the renameat2 syscall support to
fsstress, and then reproduce the deadlock problem by using fsstress.

kaixuxia (4):
  fsstress: show the real file id and parid in rename_f()
  fsstress: add NOREPLACE and WHITEOUT renameat2 support
  fsstress: add EXCHANGE renameat2 support
  xfs: test the deadlock between the AGI and AGF with RENAME_WHITEOUT

 ltp/fsstress.c        | 197 ++++++++++++++++++++++++++++++++++++++++----------
 tests/generic/579     |  56 ++++++++++++++
 tests/generic/579.out |   2 +
 tests/generic/group   |   1 +
 4 files changed, 217 insertions(+), 39 deletions(-)
 create mode 100755 tests/generic/579
 create mode 100644 tests/generic/579.out

-- 
1.8.3.1

[PATCH 1/4] fsstress: show the real file id and parid in rename_f()

[kaixuxia]

The source file id and parentid are overwritten by del_from_flist()
call, and should show the actually values.

Signed-off-by: kaixuxia <kaixuxia@tencent.com>
---
 ltp/fsstress.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/ltp/fsstress.c b/ltp/fsstress.c
index 51976f5..95285f1 100644
--- a/ltp/fsstress.c
+++ b/ltp/fsstress.c
@@ -4227,6 +4227,7 @@ rename_f(int opno, long r)
 	pathname_t	newf;
 	int		oldid;
 	int		parid;
+	int		oldparid;
 	int		v;
 	int		v1;
 
@@ -4265,10 +4266,12 @@ rename_f(int opno, long r)
 	if (e == 0) {
 		int xattr_counter = fep->xattr_counter;
 
-		if (flp - flist == FT_DIR) {
-			oldid = fep->id;
+		oldid = fep->id;
+		oldparid = fep->parent;
+
+		if (flp - flist == FT_DIR)
 			fix_parent(oldid, id);
-		}
+
 		del_from_flist(flp - flist, fep - flp->fents);
 		add_to_flist(flp - flist, id, parid, xattr_counter);
 	}
@@ -4277,7 +4280,7 @@ rename_f(int opno, long r)
 			newf.path, e);
 		if (e == 0) {
 			printf("%d/%d: rename del entry: id=%d,parent=%d\n",
-				procid, opno, fep->id, fep->parent);
+				procid, opno, oldid, oldparid);
 			printf("%d/%d: rename add entry: id=%d,parent=%d\n",
 				procid, opno, id, parid);
 		}
-- 
1.8.3.1

[PATCH 2/4] fsstress: add NOREPLACE and WHITEOUT renameat2 support

[kaixuxia]

Support the renameat2(NOREPLACE and WHITEOUT) syscall in fsstress.

Signed-off-by: kaixuxia <kaixuxia@tencent.com>
---
 ltp/fsstress.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 89 insertions(+), 15 deletions(-)

diff --git a/ltp/fsstress.c b/ltp/fsstress.c
index 95285f1..5059639 100644
--- a/ltp/fsstress.c
+++ b/ltp/fsstress.c
@@ -44,6 +44,35 @@ io_context_t	io_ctx;
 #define IOV_MAX 1024
 #endif
 
+#ifndef HAVE_RENAMEAT2
+#if !defined(SYS_renameat2) && defined(__x86_64__)
+#define SYS_renameat2 316
+#endif
+
+#if !defined(SYS_renameat2) && defined(__i386__)
+#define SYS_renameat2 353
+#endif
+
+static int renameat2(int dfd1, const char *path1,
+		     int dfd2, const char *path2,
+		     unsigned int flags)
+{
+#ifdef SYS_renameat2
+	return syscall(SYS_renameat2, dfd1, path1, dfd2, path2, flags);
+#else
+	errno = ENOSYS;
+	return -1;
+#endif
+}
+#endif
+
+#ifndef RENAME_NOREPLACE
+#define RENAME_NOREPLACE	(1 << 0)	/* Don't overwrite target */
+#endif
+#ifndef RENAME_WHITEOUT
+#define RENAME_WHITEOUT		(1 << 2)	/* Whiteout source */
+#endif
+
 #define FILELEN_MAX		(32*4096)
 
 typedef enum {
@@ -85,6 +114,8 @@ typedef enum {
 	OP_READV,
 	OP_REMOVEFATTR,
 	OP_RENAME,
+	OP_RNOREPLACE,
+	OP_RWHITEOUT,
 	OP_RESVSP,
 	OP_RMDIR,
 	OP_SETATTR,
@@ -203,6 +234,8 @@ void	readlink_f(int, long);
 void	readv_f(int, long);
 void	removefattr_f(int, long);
 void	rename_f(int, long);
+void	rnoreplace_f(int, long);
+void	rwhiteout_f(int, long);
 void	resvsp_f(int, long);
 void	rmdir_f(int, long);
 void	setattr_f(int, long);
@@ -262,6 +295,8 @@ opdesc_t	ops[] = {
 	/* remove (delete) extended attribute */
 	{ OP_REMOVEFATTR, "removefattr", removefattr_f, 1, 1 },
 	{ OP_RENAME, "rename", rename_f, 2, 1 },
+	{ OP_RNOREPLACE, "rnoreplace", rnoreplace_f, 2, 1 },
+	{ OP_RWHITEOUT, "rwhiteout", rwhiteout_f, 2, 1 },
 	{ OP_RESVSP, "resvsp", resvsp_f, 1, 1 },
 	{ OP_RMDIR, "rmdir", rmdir_f, 1, 1 },
 	/* set attribute flag (FS_IOC_SETFLAGS ioctl) */
@@ -354,7 +389,7 @@ int	open_path(pathname_t *, int);
 DIR	*opendir_path(pathname_t *);
 void	process_freq(char *);
 int	readlink_path(pathname_t *, char *, size_t);
-int	rename_path(pathname_t *, pathname_t *);
+int	rename_path(pathname_t *, pathname_t *, int);
 int	rmdir_path(pathname_t *);
 void	separate_pathname(pathname_t *, char *, pathname_t *);
 void	show_ops(int, char *);
@@ -1519,7 +1554,7 @@ readlink_path(pathname_t *name, char *lbuf, size_t lbufsiz)
 }
 
 int
-rename_path(pathname_t *name1, pathname_t *name2)
+rename_path(pathname_t *name1, pathname_t *name2, int mode)
 {
 	char		buf1[NAME_MAX + 1];
 	char		buf2[NAME_MAX + 1];
@@ -1528,14 +1563,18 @@ rename_path(pathname_t *name1, pathname_t *name2)
 	pathname_t	newname2;
 	int		rval;
 
-	rval = rename(name1->path, name2->path);
+	if (mode == 0)
+		rval = rename(name1->path, name2->path);
+	else
+		rval = renameat2(AT_FDCWD, name1->path,
+				 AT_FDCWD, name2->path, mode);
 	if (rval >= 0 || errno != ENAMETOOLONG)
 		return rval;
 	separate_pathname(name1, buf1, &newname1);
 	separate_pathname(name2, buf2, &newname2);
 	if (strcmp(buf1, buf2) == 0) {
 		if (chdir(buf1) == 0) {
-			rval = rename_path(&newname1, &newname2);
+			rval = rename_path(&newname1, &newname2, mode);
 			assert(chdir("..") == 0);
 		}
 	} else {
@@ -1555,7 +1594,7 @@ rename_path(pathname_t *name1, pathname_t *name2)
 			append_pathname(&newname2, "../");
 			append_pathname(&newname2, name2->path);
 			if (chdir(buf1) == 0) {
-				rval = rename_path(&newname1, &newname2);
+				rval = rename_path(&newname1, &newname2, mode);
 				assert(chdir("..") == 0);
 			}
 		} else {
@@ -1563,7 +1602,7 @@ rename_path(pathname_t *name1, pathname_t *name2)
 			append_pathname(&newname1, "../");
 			append_pathname(&newname1, name1->path);
 			if (chdir(buf2) == 0) {
-				rval = rename_path(&newname1, &newname2);
+				rval = rename_path(&newname1, &newname2, mode);
 				assert(chdir("..") == 0);
 			}
 		}
@@ -4215,8 +4254,17 @@ out:
 	free_pathname(&f);
 }
 
+struct print_flags renameat2_flags [] = {
+	{ RENAME_NOREPLACE, "NOREPLACE"},
+	{ RENAME_WHITEOUT, "WHITEOUT"},
+	{ -1, NULL}
+};
+
+#define translate_renameat2_flags(mode)        \
+	({translate_flags(mode, "|", renameat2_flags);})
+
 void
-rename_f(int opno, long r)
+do_renameat2(int opno, long r, int mode)
 {
 	fent_t		*dfep;
 	int		e;
@@ -4228,14 +4276,17 @@ rename_f(int opno, long r)
 	int		oldid;
 	int		parid;
 	int		oldparid;
+	int		which;
 	int		v;
 	int		v1;
 
 	/* get an existing path for the source of the rename */
 	init_pathname(&f);
-	if (!get_fname(FT_ANYm, r, &f, &flp, &fep, &v1)) {
+	which = (mode == RENAME_WHITEOUT) ? FT_DEVm : FT_ANYm;
+	if (!get_fname(which, r, &f, &flp, &fep, &v1)) {
 		if (v1)
-			printf("%d/%d: rename - no filename\n", procid, opno);
+			printf("%d/%d: rename - no source filename\n",
+				procid, opno);
 		free_pathname(&f);
 		return;
 	}
@@ -4261,7 +4312,7 @@ rename_f(int opno, long r)
 		free_pathname(&f);
 		return;
 	}
-	e = rename_path(&f, &newf) < 0 ? errno : 0;
+	e = rename_path(&f, &newf, mode) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0) {
 		int xattr_counter = fep->xattr_counter;
@@ -4272,16 +4323,21 @@ rename_f(int opno, long r)
 		if (flp - flist == FT_DIR)
 			fix_parent(oldid, id);
 
-		del_from_flist(flp - flist, fep - flp->fents);
-		add_to_flist(flp - flist, id, parid, xattr_counter);
+		if (mode == RENAME_WHITEOUT)
+			add_to_flist(flp - flist, id, parid, xattr_counter);
+		else {
+			del_from_flist(flp - flist, fep - flp->fents);
+			add_to_flist(flp - flist, id, parid, xattr_counter);
+		}
 	}
 	if (v) {
-		printf("%d/%d: rename %s to %s %d\n", procid, opno, f.path,
+		printf("%d/%d: rename(%s) %s to %s %d\n", procid,
+			opno, translate_renameat2_flags(mode), f.path,
 			newf.path, e);
 		if (e == 0) {
-			printf("%d/%d: rename del entry: id=%d,parent=%d\n",
+			printf("%d/%d: rename source entry: id=%d,parent=%d\n",
 				procid, opno, oldid, oldparid);
-			printf("%d/%d: rename add entry: id=%d,parent=%d\n",
+			printf("%d/%d: rename target entry: id=%d,parent=%d\n",
 				procid, opno, id, parid);
 		}
 	}
@@ -4290,6 +4346,24 @@ rename_f(int opno, long r)
 }
 
 void
+rename_f(int opno, long r)
+{
+	do_renameat2(opno, r, 0);
+}
+
+void
+rnoreplace_f(int opno, long r)
+{
+	do_renameat2(opno, r, RENAME_NOREPLACE);
+}
+
+void
+rwhiteout_f(int opno, long r)
+{
+	do_renameat2(opno, r, RENAME_WHITEOUT);
+}
+
+void
 resvsp_f(int opno, long r)
 {
 	int		e;
-- 
1.8.3.1

[PATCH 3/4] fsstress: add EXCHANGE renameat2 support

[kaixuxia]

Support the EXCHANGE renameat2 syscall in fsstress.

Signed-off-by: kaixuxia <kaixuxia@tencent.com>
---
 ltp/fsstress.c | 86 +++++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 64 insertions(+), 22 deletions(-)

diff --git a/ltp/fsstress.c b/ltp/fsstress.c
index 5059639..958adf9 100644
--- a/ltp/fsstress.c
+++ b/ltp/fsstress.c
@@ -69,6 +69,9 @@ static int renameat2(int dfd1, const char *path1,
 #ifndef RENAME_NOREPLACE
 #define RENAME_NOREPLACE	(1 << 0)	/* Don't overwrite target */
 #endif
+#ifndef RENAME_EXCHANGE
+#define RENAME_EXCHANGE		(1 << 1)	/* Exchange source and dest */
+#endif
 #ifndef RENAME_WHITEOUT
 #define RENAME_WHITEOUT		(1 << 2)	/* Whiteout source */
 #endif
@@ -115,6 +118,7 @@ typedef enum {
 	OP_REMOVEFATTR,
 	OP_RENAME,
 	OP_RNOREPLACE,
+	OP_REXCHANGE,
 	OP_RWHITEOUT,
 	OP_RESVSP,
 	OP_RMDIR,
@@ -235,6 +239,7 @@ void	readv_f(int, long);
 void	removefattr_f(int, long);
 void	rename_f(int, long);
 void	rnoreplace_f(int, long);
+void	rexchange_f(int, long);
 void	rwhiteout_f(int, long);
 void	resvsp_f(int, long);
 void	rmdir_f(int, long);
@@ -296,6 +301,7 @@ opdesc_t	ops[] = {
 	{ OP_REMOVEFATTR, "removefattr", removefattr_f, 1, 1 },
 	{ OP_RENAME, "rename", rename_f, 2, 1 },
 	{ OP_RNOREPLACE, "rnoreplace", rnoreplace_f, 2, 1 },
+	{ OP_REXCHANGE, "rexchange", rexchange_f, 2, 1 },
 	{ OP_RWHITEOUT, "rwhiteout", rwhiteout_f, 2, 1 },
 	{ OP_RESVSP, "resvsp", resvsp_f, 1, 1 },
 	{ OP_RMDIR, "rmdir", rmdir_f, 1, 1 },
@@ -371,7 +377,7 @@ void	del_from_flist(int, int);
 int	dirid_to_name(char *, int);
 void	doproc(void);
 int	fent_to_name(pathname_t *, flist_t *, fent_t *);
-void	fix_parent(int, int);
+void	fix_parent(int, int, int);
 void	free_pathname(pathname_t *);
 int	generate_fname(fent_t *, int, pathname_t *, int *, int *);
 int	generate_xattr_name(int, char *, int);
@@ -1118,7 +1124,7 @@ fent_to_name(pathname_t *name, flist_t *flp, fent_t *fep)
 }
 
 void
-fix_parent(int oldid, int newid)
+fix_parent(int oldid, int newid, int swap)
 {
 	fent_t	*fep;
 	flist_t	*flp;
@@ -1129,6 +1135,8 @@ fix_parent(int oldid, int newid)
 		for (j = 0, fep = flp->fents; j < flp->nfiles; j++, fep++) {
 			if (fep->parent == oldid)
 				fep->parent = newid;
+			if (swap && fep->parent == newid)
+				fep->parent = oldid;
 		}
 	}
 }
@@ -4256,6 +4264,7 @@ out:
 
 struct print_flags renameat2_flags [] = {
 	{ RENAME_NOREPLACE, "NOREPLACE"},
+	{ RENAME_EXCHANGE, "EXCHANGE"},
 	{ RENAME_WHITEOUT, "WHITEOUT"},
 	{ -1, NULL}
 };
@@ -4291,41 +4300,68 @@ do_renameat2(int opno, long r, int mode)
 		return;
 	}
 
-	/* get an existing directory for the destination parent directory name */
-	if (!get_fname(FT_DIRm, random(), NULL, NULL, &dfep, &v))
-		parid = -1;
-	else
-		parid = dfep->id;
-	v |= v1;
+	/* Both pathnames must exist for the RENAME_EXCHANGE */
+	if (mode == RENAME_EXCHANGE) {
+		which = 1 << (flp - flist);
+		init_pathname(&newf);
+		if (!get_fname(which, random(), &newf, NULL, &dfep, &v)) {
+			if (v)
+				printf("%d/%d: rename - no target filename\n",
+					procid, opno);
+			free_pathname(&newf);
+			free_pathname(&f);
+			return;
+		}
+		v |= v1;
+		id = dfep->id;
+		parid = dfep->parent;
+	} else {
+		/*
+		 * get an existing directory for the destination parent
+		 * directory name.
+		 */
+		if (!get_fname(FT_DIRm, random(), NULL, NULL, &dfep, &v))
+			parid = -1;
+		else
+			parid = dfep->id;
+		v |= v1;
 
-	/* generate a new path using an existing parent directory in name */
-	init_pathname(&newf);
-	e = generate_fname(dfep, flp - flist, &newf, &id, &v1);
-	v |= v1;
-	if (!e) {
-		if (v) {
-			(void)fent_to_name(&f, &flist[FT_DIR], dfep);
-			printf("%d/%d: rename - no filename from %s\n",
-				procid, opno, f.path);
+		/*
+		 * generate a new path using an existing parent directory
+		 * in name.
+		 */
+		init_pathname(&newf);
+		e = generate_fname(dfep, flp - flist, &newf, &id, &v1);
+		v |= v1;
+		if (!e) {
+			if (v) {
+				(void)fent_to_name(&f, &flist[FT_DIR], dfep);
+				printf("%d/%d: rename - no filename from %s\n",
+					procid, opno, f.path);
+			}
+			free_pathname(&newf);
+			free_pathname(&f);
+			return;
 		}
-		free_pathname(&newf);
-		free_pathname(&f);
-		return;
 	}
 	e = rename_path(&f, &newf, mode) < 0 ? errno : 0;
 	check_cwd();
 	if (e == 0) {
 		int xattr_counter = fep->xattr_counter;
+		int swap = (mode == RENAME_EXCHANGE) ? 1 : 0;
 
 		oldid = fep->id;
 		oldparid = fep->parent;
 
 		if (flp - flist == FT_DIR)
-			fix_parent(oldid, id);
+			fix_parent(oldid, id, swap);
 
 		if (mode == RENAME_WHITEOUT)
 			add_to_flist(flp - flist, id, parid, xattr_counter);
-		else {
+		else if (mode == RENAME_EXCHANGE) {
+			fep->xattr_counter = dfep->xattr_counter;
+			dfep->xattr_counter = xattr_counter;
+		} else {
 			del_from_flist(flp - flist, fep - flp->fents);
 			add_to_flist(flp - flist, id, parid, xattr_counter);
 		}
@@ -4358,6 +4394,12 @@ rnoreplace_f(int opno, long r)
 }
 
 void
+rexchange_f(int opno, long r)
+{
+	do_renameat2(opno, r, RENAME_EXCHANGE);
+}
+
+void
 rwhiteout_f(int opno, long r)
 {
 	do_renameat2(opno, r, RENAME_WHITEOUT);
-- 
1.8.3.1

[PATCH 4/4] xfs: test the deadlock between the AGI and AGF with RENAME_WHITEOUT

[kaixuxia]

There is ABBA deadlock bug between the AGI and AGF when performing
rename() with RENAME_WHITEOUT flag, and add this testcase to make
sure the rename() call works well.

Signed-off-by: kaixuxia <kaixuxia@tencent.com>
---
 tests/generic/579     | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/579.out |  2 ++
 tests/generic/group   |  1 +
 3 files changed, 59 insertions(+)
 create mode 100755 tests/generic/579
 create mode 100644 tests/generic/579.out

diff --git a/tests/generic/579 b/tests/generic/579
new file mode 100755
index 0000000..95727f3
--- /dev/null
+++ b/tests/generic/579
@@ -0,0 +1,56 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2019 Tencent.  All Rights Reserved.
+#
+# FS QA Test No. 579
+#
+# Regression test for:
+#    bc56ad8c74b8: ("xfs: Fix deadlock between AGI and AGF with RENAME_WHITEOUT")
+#
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1        # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+        cd /
+        rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/renameat2
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_os Linux
+_supported_fs generic
+_require_scratch
+_require_renameat2 whiteout
+
+_scratch_mkfs > $seqres.full 2>&1 || _fail "mkfs failed"
+_scratch_mount >> $seqres.full 2>&1
+
+# start a create and rename(rename_whiteout) workload. These processes
+# occur simultaneously may cause the deadlock between AGI and AGF with
+# RENAME_WHITEOUT.
+$FSSTRESS_PROG -z -n 150 -p 100 \
+		-f mknod=5 \
+		-f rwhiteout=5 \
+		-d $SCRATCH_MNT/fsstress >> $seqres.full 2>&1
+
+echo Silence is golden
+
+# Failure comes in the form of a deadlock.
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/579.out b/tests/generic/579.out
new file mode 100644
index 0000000..06f4633
--- /dev/null
+++ b/tests/generic/579.out
@@ -0,0 +1,2 @@
+QA output created by 579
+Silence is golden
diff --git a/tests/generic/group b/tests/generic/group
index 6f9c4e1..21870d2 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -581,3 +581,4 @@
 576 auto quick verity encrypt
 577 auto quick verity
 578 auto quick rw clone
+579 auto rename
-- 
1.8.3.1

Re: [PATCH 1/4] fsstress: show the real file id and parid in rename_f()

[Brian Foster]

On Thu, Oct 24, 2019 at 10:20:48PM +0800, kaixuxia wrote:
> The source file id and parentid are overwritten by del_from_flist()
> call, and should show the actually values.
> 
> Signed-off-by: kaixuxia <kaixuxia@tencent.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

>  ltp/fsstress.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
> index 51976f5..95285f1 100644
> --- a/ltp/fsstress.c
> +++ b/ltp/fsstress.c
> @@ -4227,6 +4227,7 @@ rename_f(int opno, long r)
>  	pathname_t	newf;
>  	int		oldid;
>  	int		parid;
> +	int		oldparid;
>  	int		v;
>  	int		v1;
>  
> @@ -4265,10 +4266,12 @@ rename_f(int opno, long r)
>  	if (e == 0) {
>  		int xattr_counter = fep->xattr_counter;
>  
> -		if (flp - flist == FT_DIR) {
> -			oldid = fep->id;
> +		oldid = fep->id;
> +		oldparid = fep->parent;
> +
> +		if (flp - flist == FT_DIR)
>  			fix_parent(oldid, id);
> -		}
> +
>  		del_from_flist(flp - flist, fep - flp->fents);
>  		add_to_flist(flp - flist, id, parid, xattr_counter);
>  	}
> @@ -4277,7 +4280,7 @@ rename_f(int opno, long r)
>  			newf.path, e);
>  		if (e == 0) {
>  			printf("%d/%d: rename del entry: id=%d,parent=%d\n",
> -				procid, opno, fep->id, fep->parent);
> +				procid, opno, oldid, oldparid);
>  			printf("%d/%d: rename add entry: id=%d,parent=%d\n",
>  				procid, opno, id, parid);
>  		}
> -- 
> 1.8.3.1
> 

Re: [PATCH 2/4] fsstress: add NOREPLACE and WHITEOUT renameat2 support

[Brian Foster]

On Thu, Oct 24, 2019 at 10:20:49PM +0800, kaixuxia wrote:
> Support the renameat2(NOREPLACE and WHITEOUT) syscall in fsstress.
> 
> Signed-off-by: kaixuxia <kaixuxia@tencent.com>
> ---
>  ltp/fsstress.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++---------
>  1 file changed, 89 insertions(+), 15 deletions(-)
> 
> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
> index 95285f1..5059639 100644
> --- a/ltp/fsstress.c
> +++ b/ltp/fsstress.c
...
> @@ -4272,16 +4323,21 @@ rename_f(int opno, long r)
>  		if (flp - flist == FT_DIR)
>  			fix_parent(oldid, id);
>  
> -		del_from_flist(flp - flist, fep - flp->fents);
> -		add_to_flist(flp - flist, id, parid, xattr_counter);
> +		if (mode == RENAME_WHITEOUT)
> +			add_to_flist(flp - flist, id, parid, xattr_counter);

Hmm, so we've added a new devnode for the target and a whiteout was
added in its place. What about the xattr_count of the original devnode?
I wonder if we should reset that to zero. Other than that the rest looks
fine to me.

Brian

> +		else {
> +			del_from_flist(flp - flist, fep - flp->fents);
> +			add_to_flist(flp - flist, id, parid, xattr_counter);
> +		}
>  	}
>  	if (v) {
> -		printf("%d/%d: rename %s to %s %d\n", procid, opno, f.path,
> +		printf("%d/%d: rename(%s) %s to %s %d\n", procid,
> +			opno, translate_renameat2_flags(mode), f.path,
>  			newf.path, e);
>  		if (e == 0) {
> -			printf("%d/%d: rename del entry: id=%d,parent=%d\n",
> +			printf("%d/%d: rename source entry: id=%d,parent=%d\n",
>  				procid, opno, oldid, oldparid);
> -			printf("%d/%d: rename add entry: id=%d,parent=%d\n",
> +			printf("%d/%d: rename target entry: id=%d,parent=%d\n",
>  				procid, opno, id, parid);
>  		}
>  	}
> @@ -4290,6 +4346,24 @@ rename_f(int opno, long r)
>  }
>  
>  void
> +rename_f(int opno, long r)
> +{
> +	do_renameat2(opno, r, 0);
> +}
> +
> +void
> +rnoreplace_f(int opno, long r)
> +{
> +	do_renameat2(opno, r, RENAME_NOREPLACE);
> +}
> +
> +void
> +rwhiteout_f(int opno, long r)
> +{
> +	do_renameat2(opno, r, RENAME_WHITEOUT);
> +}
> +
> +void
>  resvsp_f(int opno, long r)
>  {
>  	int		e;
> -- 
> 1.8.3.1
> 

Re: [PATCH 3/4] fsstress: add EXCHANGE renameat2 support

[Brian Foster]

On Thu, Oct 24, 2019 at 10:20:50PM +0800, kaixuxia wrote:
> Support the EXCHANGE renameat2 syscall in fsstress.
> 
> Signed-off-by: kaixuxia <kaixuxia@tencent.com>
> ---
>  ltp/fsstress.c | 86 +++++++++++++++++++++++++++++++++++++++++++---------------
>  1 file changed, 64 insertions(+), 22 deletions(-)
> 
> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
> index 5059639..958adf9 100644
> --- a/ltp/fsstress.c
> +++ b/ltp/fsstress.c
...
> @@ -1118,7 +1124,7 @@ fent_to_name(pathname_t *name, flist_t *flp, fent_t *fep)
>  }
>  
>  void
> -fix_parent(int oldid, int newid)
> +fix_parent(int oldid, int newid, int swap)
>  {
>  	fent_t	*fep;
>  	flist_t	*flp;
> @@ -1129,6 +1135,8 @@ fix_parent(int oldid, int newid)
>  		for (j = 0, fep = flp->fents; j < flp->nfiles; j++, fep++) {
>  			if (fep->parent == oldid)
>  				fep->parent = newid;
> +			if (swap && fep->parent == newid)
> +				fep->parent = oldid;

We might as well use a bool for swap.

>  		}
>  	}
>  }
> @@ -4256,6 +4264,7 @@ out:
>  
>  struct print_flags renameat2_flags [] = {
>  	{ RENAME_NOREPLACE, "NOREPLACE"},
> +	{ RENAME_EXCHANGE, "EXCHANGE"},
>  	{ RENAME_WHITEOUT, "WHITEOUT"},
>  	{ -1, NULL}
>  };
> @@ -4291,41 +4300,68 @@ do_renameat2(int opno, long r, int mode)
>  		return;
>  	}
>  
> -	/* get an existing directory for the destination parent directory name */
> -	if (!get_fname(FT_DIRm, random(), NULL, NULL, &dfep, &v))
> -		parid = -1;
> -	else
> -		parid = dfep->id;
> -	v |= v1;
> +	/* Both pathnames must exist for the RENAME_EXCHANGE */

This comment should also say that the types must be the same.

> +	if (mode == RENAME_EXCHANGE) {
> +		which = 1 << (flp - flist);
> +		init_pathname(&newf);
> +		if (!get_fname(which, random(), &newf, NULL, &dfep, &v)) {
> +			if (v)
> +				printf("%d/%d: rename - no target filename\n",
> +					procid, opno);
> +			free_pathname(&newf);
> +			free_pathname(&f);
> +			return;
> +		}
> +		v |= v1;
> +		id = dfep->id;
> +		parid = dfep->parent;
> +	} else {
> +		/*
> +		 * get an existing directory for the destination parent
> +		 * directory name.
> +		 */
> +		if (!get_fname(FT_DIRm, random(), NULL, NULL, &dfep, &v))
> +			parid = -1;
> +		else
> +			parid = dfep->id;
> +		v |= v1;
>  
> -	/* generate a new path using an existing parent directory in name */
> -	init_pathname(&newf);
> -	e = generate_fname(dfep, flp - flist, &newf, &id, &v1);
> -	v |= v1;
> -	if (!e) {
> -		if (v) {
> -			(void)fent_to_name(&f, &flist[FT_DIR], dfep);
> -			printf("%d/%d: rename - no filename from %s\n",
> -				procid, opno, f.path);
> +		/*
> +		 * generate a new path using an existing parent directory
> +		 * in name.
> +		 */
> +		init_pathname(&newf);
> +		e = generate_fname(dfep, flp - flist, &newf, &id, &v1);
> +		v |= v1;
> +		if (!e) {
> +			if (v) {
> +				(void)fent_to_name(&f, &flist[FT_DIR], dfep);
> +				printf("%d/%d: rename - no filename from %s\n",
> +					procid, opno, f.path);
> +			}
> +			free_pathname(&newf);
> +			free_pathname(&f);
> +			return;
>  		}
> -		free_pathname(&newf);
> -		free_pathname(&f);
> -		return;
>  	}
>  	e = rename_path(&f, &newf, mode) < 0 ? errno : 0;
>  	check_cwd();
>  	if (e == 0) {
>  		int xattr_counter = fep->xattr_counter;
> +		int swap = (mode == RENAME_EXCHANGE) ? 1 : 0;
>  
>  		oldid = fep->id;
>  		oldparid = fep->parent;
>  
>  		if (flp - flist == FT_DIR)
> -			fix_parent(oldid, id);
> +			fix_parent(oldid, id, swap);

What about the other directory if we exchanged two dirs (also see my
comment on the previous version around the safety of doing two separate
swaps)? BTW however this turns out, it would also be useful to see some
comments in this area of code to explain it along with some content in
the commit log descriptions of both patches to document the limitations
of the various renameat2 modes.

Brian

>  
>  		if (mode == RENAME_WHITEOUT)
>  			add_to_flist(flp - flist, id, parid, xattr_counter);
> -		else {
> +		else if (mode == RENAME_EXCHANGE) {
> +			fep->xattr_counter = dfep->xattr_counter;
> +			dfep->xattr_counter = xattr_counter;
> +		} else {
>  			del_from_flist(flp - flist, fep - flp->fents);
>  			add_to_flist(flp - flist, id, parid, xattr_counter);
>  		}
> @@ -4358,6 +4394,12 @@ rnoreplace_f(int opno, long r)
>  }
>  
>  void
> +rexchange_f(int opno, long r)
> +{
> +	do_renameat2(opno, r, RENAME_EXCHANGE);
> +}
> +
> +void
>  rwhiteout_f(int opno, long r)
>  {
>  	do_renameat2(opno, r, RENAME_WHITEOUT);
> -- 
> 1.8.3.1
> 

Re: [PATCH 4/4] xfs: test the deadlock between the AGI and AGF with RENAME_WHITEOUT

[Brian Foster]

On Thu, Oct 24, 2019 at 10:20:51PM +0800, kaixuxia wrote:
> There is ABBA deadlock bug between the AGI and AGF when performing
> rename() with RENAME_WHITEOUT flag, and add this testcase to make
> sure the rename() call works well.
> 
> Signed-off-by: kaixuxia <kaixuxia@tencent.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

>  tests/generic/579     | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/579.out |  2 ++
>  tests/generic/group   |  1 +
>  3 files changed, 59 insertions(+)
>  create mode 100755 tests/generic/579
>  create mode 100644 tests/generic/579.out
> 
> diff --git a/tests/generic/579 b/tests/generic/579
> new file mode 100755
> index 0000000..95727f3
> --- /dev/null
> +++ b/tests/generic/579
> @@ -0,0 +1,56 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2019 Tencent.  All Rights Reserved.
> +#
> +# FS QA Test No. 579
> +#
> +# Regression test for:
> +#    bc56ad8c74b8: ("xfs: Fix deadlock between AGI and AGF with RENAME_WHITEOUT")
> +#
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +tmp=/tmp/$$
> +status=1        # failure is the default!
> +trap "_cleanup; exit \$status" 0 1 2 3 15
> +
> +_cleanup()
> +{
> +        cd /
> +        rm -f $tmp.*
> +}
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +. ./common/renameat2
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +_supported_os Linux
> +_supported_fs generic
> +_require_scratch
> +_require_renameat2 whiteout
> +
> +_scratch_mkfs > $seqres.full 2>&1 || _fail "mkfs failed"
> +_scratch_mount >> $seqres.full 2>&1
> +
> +# start a create and rename(rename_whiteout) workload. These processes
> +# occur simultaneously may cause the deadlock between AGI and AGF with
> +# RENAME_WHITEOUT.
> +$FSSTRESS_PROG -z -n 150 -p 100 \
> +		-f mknod=5 \
> +		-f rwhiteout=5 \
> +		-d $SCRATCH_MNT/fsstress >> $seqres.full 2>&1
> +
> +echo Silence is golden
> +
> +# Failure comes in the form of a deadlock.
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/generic/579.out b/tests/generic/579.out
> new file mode 100644
> index 0000000..06f4633
> --- /dev/null
> +++ b/tests/generic/579.out
> @@ -0,0 +1,2 @@
> +QA output created by 579
> +Silence is golden
> diff --git a/tests/generic/group b/tests/generic/group
> index 6f9c4e1..21870d2 100644
> --- a/tests/generic/group
> +++ b/tests/generic/group
> @@ -581,3 +581,4 @@
>  576 auto quick verity encrypt
>  577 auto quick verity
>  578 auto quick rw clone
> +579 auto rename
> -- 
> 1.8.3.1
>