KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 165 insertions, 0 deletions

diff --git a/include/trace/misc/fs.h b/include/trace/misc/fs.h
new file mode 100644
index 000000000..7ead1c61f
--- /dev/null
+++ b/include/trace/misc/fs.h
@@ -0,0 +1,165 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Display helpers for generic filesystem items
+ *
+ * Author: Chuck Lever <chuck.lever@oracle.com>
+ *
+ * Copyright (c) 2020, Oracle and/or its affiliates.
+ */
+
+#include <linux/fs.h>
+
+#define show_fs_dirent_type(x) \
+	__print_symbolic(x, \
+		{ DT_UNKNOWN,		"UNKNOWN" }, \
+		{ DT_FIFO,		"FIFO" }, \
+		{ DT_CHR,		"CHR" }, \
+		{ DT_DIR,		"DIR" }, \
+		{ DT_BLK,		"BLK" }, \
+		{ DT_REG,		"REG" }, \
+		{ DT_LNK,		"LNK" }, \
+		{ DT_SOCK,		"SOCK" }, \
+		{ DT_WHT,		"WHT" })
+
+#define show_fs_fcntl_open_flags(x) \
+	__print_flags(x, "|", \
+		{ O_WRONLY,		"O_WRONLY" }, \
+		{ O_RDWR,		"O_RDWR" }, \
+		{ O_CREAT,		"O_CREAT" }, \
+		{ O_EXCL,		"O_EXCL" }, \
+		{ O_NOCTTY,		"O_NOCTTY" }, \
+		{ O_TRUNC,		"O_TRUNC" }, \
+		{ O_APPEND,		"O_APPEND" }, \
+		{ O_NONBLOCK,		"O_NONBLOCK" }, \
+		{ O_DSYNC,		"O_DSYNC" }, \
+		{ O_DIRECT,		"O_DIRECT" }, \
+		{ O_LARGEFILE,		"O_LARGEFILE" }, \
+		{ O_DIRECTORY,		"O_DIRECTORY" }, \
+		{ O_NOFOLLOW,		"O_NOFOLLOW" }, \
+		{ O_NOATIME,		"O_NOATIME" }, \
+		{ O_CLOEXEC,		"O_CLOEXEC" })
+
+#define __fmode_flag(x)	{ (__force unsigned long)FMODE_##x, #x }
+#define show_fs_fmode_flags(x) \
+	__print_flags(x, "|", \
+		__fmode_flag(READ), \
+		__fmode_flag(WRITE), \
+		__fmode_flag(EXEC))
+
+#ifdef CONFIG_64BIT
+#define show_fs_fcntl_cmd(x) \
+	__print_symbolic(x, \
+		{ F_DUPFD,		"DUPFD" }, \
+		{ F_GETFD,		"GETFD" }, \
+		{ F_SETFD,		"SETFD" }, \
+		{ F_GETFL,		"GETFL" }, \
+		{ F_SETFL,		"SETFL" }, \
+		{ F_GETLK,		"GETLK" }, \
+		{ F_SETLK,		"SETLK" }, \
+		{ F_SETLKW,		"SETLKW" }, \
+		{ F_SETOWN,		"SETOWN" }, \
+		{ F_GETOWN,		"GETOWN" }, \
+		{ F_SETSIG,		"SETSIG" }, \
+		{ F_GETSIG,		"GETSIG" }, \
+		{ F_SETOWN_EX,		"SETOWN_EX" }, \
+		{ F_GETOWN_EX,		"GETOWN_EX" }, \
+		{ F_GETOWNER_UIDS,	"GETOWNER_UIDS" }, \
+		{ F_OFD_GETLK,		"OFD_GETLK" }, \
+		{ F_OFD_SETLK,		"OFD_SETLK" }, \
+		{ F_OFD_SETLKW,		"OFD_SETLKW" })
+#else /* CONFIG_64BIT */
+#define show_fs_fcntl_cmd(x) \
+	__print_symbolic(x, \
+		{ F_DUPFD,		"DUPFD" }, \
+		{ F_GETFD,		"GETFD" }, \
+		{ F_SETFD,		"SETFD" }, \
+		{ F_GETFL,		"GETFL" }, \
+		{ F_SETFL,		"SETFL" }, \
+		{ F_GETLK,		"GETLK" }, \
+		{ F_SETLK,		"SETLK" }, \
+		{ F_SETLKW,		"SETLKW" }, \
+		{ F_SETOWN,		"SETOWN" }, \
+		{ F_GETOWN,		"GETOWN" }, \
+		{ F_SETSIG,		"SETSIG" }, \
+		{ F_GETSIG,		"GETSIG" }, \
+		{ F_GETLK64,		"GETLK64" }, \
+		{ F_SETLK64,		"SETLK64" }, \
+		{ F_SETLKW64,		"SETLKW64" }, \
+		{ F_SETOWN_EX,		"SETOWN_EX" }, \
+		{ F_GETOWN_EX,		"GETOWN_EX" }, \
+		{ F_GETOWNER_UIDS,	"GETOWNER_UIDS" }, \
+		{ F_OFD_GETLK,		"OFD_GETLK" }, \
+		{ F_OFD_SETLK,		"OFD_SETLK" }, \
+		{ F_OFD_SETLKW,		"OFD_SETLKW" })
+#endif /* CONFIG_64BIT */
+
+#define show_fs_fcntl_lock_type(x) \
+	__print_symbolic(x, \
+		{ F_RDLCK,		"RDLCK" }, \
+		{ F_WRLCK,		"WRLCK" }, \
+		{ F_UNLCK,		"UNLCK" })
+
+#define show_fs_lookup_flags(flags) \
+	__print_flags(flags, "|", \
+		{ LOOKUP_FOLLOW,	"FOLLOW" }, \
+		{ LOOKUP_DIRECTORY,	"DIRECTORY" }, \
+		{ LOOKUP_AUTOMOUNT,	"AUTOMOUNT" }, \
+		{ LOOKUP_EMPTY,		"EMPTY" }, \
+		{ LOOKUP_DOWN,		"DOWN" }, \
+		{ LOOKUP_MOUNTPOINT,	"MOUNTPOINT" }, \
+		{ LOOKUP_REVAL,		"REVAL" }, \
+		{ LOOKUP_RCU,		"RCU" }, \
+		{ LOOKUP_OPEN,		"OPEN" }, \
+		{ LOOKUP_CREATE,	"CREATE" }, \
+		{ LOOKUP_EXCL,		"EXCL" }, \
+		{ LOOKUP_RENAME_TARGET,	"RENAME_TARGET" }, \
+		{ LOOKUP_PARENT,	"PARENT" }, \
+		{ LOOKUP_NO_SYMLINKS,	"NO_SYMLINKS" }, \
+		{ LOOKUP_NO_MAGICLINKS,	"NO_MAGICLINKS" }, \
+		{ LOOKUP_NO_XDEV,	"NO_XDEV" }, \
+		{ LOOKUP_BENEATH,	"BENEATH" }, \
+		{ LOOKUP_IN_ROOT,	"IN_ROOT" }, \
+		{ LOOKUP_CACHED,	"CACHED" })
+
+#define show_ia_valid_flags(flags)			\
+	__print_flags(flags, "|",			\
+		{ ATTR_MODE,		"MODE" },	\
+		{ ATTR_UID,		"UID" },	\
+		{ ATTR_GID,		"GID" },	\
+		{ ATTR_SIZE,		"SIZE" },	\
+		{ ATTR_ATIME,		"ATIME" },	\
+		{ ATTR_MTIME,		"MTIME" },	\
+		{ ATTR_CTIME,		"CTIME" },	\
+		{ ATTR_ATIME_SET,	"ATIME_SET" },	\
+		{ ATTR_MTIME_SET,	"MTIME_SET" },	\
+		{ ATTR_FORCE,		"FORCE" },	\
+		{ ATTR_KILL_SUID,	"KILL_SUID" },	\
+		{ ATTR_KILL_SGID,	"KILL_SGID" },	\
+		{ ATTR_FILE,		"FILE" },	\
+		{ ATTR_KILL_PRIV,	"KILL_PRIV" },	\
+		{ ATTR_OPEN,		"OPEN" },	\
+		{ ATTR_TIMES_SET,	"TIMES_SET" },	\
+		{ ATTR_TOUCH,		"TOUCH"},	\
+		{ ATTR_DELEG,		"DELEG"})
+
+#define show_statx_mask(flags)					\
+	__print_flags(flags, "|",				\
+		{ STATX_TYPE,		"TYPE" },		\
+		{ STATX_MODE,		"MODE" },		\
+		{ STATX_NLINK,		"NLINK" },		\
+		{ STATX_UID,		"UID" },		\
+		{ STATX_GID,		"GID" },		\
+		{ STATX_ATIME,		"ATIME" },		\
+		{ STATX_MTIME,		"MTIME" },		\
+		{ STATX_CTIME,		"CTIME" },		\
+		{ STATX_INO,		"INO" },		\
+		{ STATX_SIZE,		"SIZE" },		\
+		{ STATX_BLOCKS,		"BLOCKS" },		\
+		{ STATX_BASIC_STATS,	"BASIC_STATS" },	\
+		{ STATX_BTIME,		"BTIME" },		\
+		{ STATX_MNT_ID,		"MNT_ID" },		\
+		{ STATX_DIOALIGN,	"DIOALIGN" },		\
+		{ STATX_MNT_ID_UNIQUE,	"MNT_ID_UNIQUE" },	\
+		{ STATX_SUBVOL,		"SUBVOL" },		\
+		{ STATX_WRITE_ATOMIC,	"WRITE_ATOMIC" },	\
+		{ STATX_DIO_READ_ALIGN,	"DIO_READ_ALIGN" })