From 3934e36f6099e6277db33f433fe135c6644e8ac2 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Sat, 14 Dec 2019 13:26:33 -0700
Subject: [PATCH] fs: make two stat prep helpers available
To implement an async stat, we need to provide the flags mapping and
the statx user copy. Make them available internally, through
fs/internal.h.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
fs/internal.h | 6 ++++++
fs/stat.c | 34 ++++++++++++++++++++++------------
2 files changed, 28 insertions(+), 12 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index c4baf42f8d8a..54e2835c0eba 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -190,3 +190,9 @@ extern int do_vfs_ioctl(struct file *file, unsigned int fd, unsigned int cmd,
/* direct-io.c: */
int sb_init_dio_done_wq(struct super_block *sb);
+
+/*
+ * fs/stat.c:
+ */
+unsigned vfs_stat_set_lookup_flags(unsigned *lookup_flags, int flags);
+int cp_statx(const struct kstat *stat, struct statx __user *buffer);
diff --git a/fs/stat.c b/fs/stat.c
index c38e4c2e1221..030008796479 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -21,6 +21,8 @@
#include <linux/uaccess.h>
#include <asm/unistd.h>
+#include "internal.h"
+
/**
* generic_fillattr - Fill in the basic attributes from the inode struct
* @inode: Inode to use as the source
@@ -150,6 +152,23 @@ int vfs_statx_fd(unsigned int fd, struct kstat *stat,
}
EXPORT_SYMBOL(vfs_statx_fd);
+inline unsigned vfs_stat_set_lookup_flags(unsigned *lookup_flags, int flags)
+{
+ if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
+ AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
+ return -EINVAL;
+
+ *lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
+ if (flags & AT_SYMLINK_NOFOLLOW)
+ *lookup_flags &= ~LOOKUP_FOLLOW;
+ if (flags & AT_NO_AUTOMOUNT)
+ *lookup_flags &= ~LOOKUP_AUTOMOUNT;
+ if (flags & AT_EMPTY_PATH)
+ *lookup_flags |= LOOKUP_EMPTY;
+
+ return 0;
+}
+
/**
* vfs_statx - Get basic and extra attributes by filename
* @dfd: A file descriptor representing the base dir for a relative filename
@@ -170,19 +189,10 @@ int vfs_statx(int dfd, const char __user *filename, int flags,
{
struct path path;
int error = -EINVAL;
- unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
+ unsigned lookup_flags;
- if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
- AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
+ if (vfs_stat_set_lookup_flags(&lookup_flags, flags))
return -EINVAL;
-
- if (flags & AT_SYMLINK_NOFOLLOW)
- lookup_flags &= ~LOOKUP_FOLLOW;
- if (flags & AT_NO_AUTOMOUNT)
- lookup_flags &= ~LOOKUP_AUTOMOUNT;
- if (flags & AT_EMPTY_PATH)
- lookup_flags |= LOOKUP_EMPTY;
-
retry:
error = user_path_at(dfd, filename, lookup_flags, &path);
if (error)
@@ -523,7 +533,7 @@ SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
}
#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
-static noinline_for_stack int
+noinline_for_stack int
cp_statx(const struct kstat *stat, struct statx __user *buffer)
{
struct statx tmp;