Linux-Fsdevel Archive on lore.kernel.org
 help / color / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: Alexander Viro <viro@zeniv.linux.org.uk>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org, y2038@lists.linaro.org,
	Arnd Bergmann <arnd@arndb.de>,
	linux-kernel@vger.kernel.org
Subject: [PATCH] initramfs: use vfs_stat/lstat directly
Date: Tue, 14 Mar 2017 22:49:05 +0100
Message-ID: <20170314214932.4052842-1-arnd@arndb.de> (raw)

sys_newlstat is a system call implementation that is meant for user
space, and that copies kernel-internal data structure to the user
format, which is not needed for in-kernel users.

Further, as we rearrange the system call implementation so we can
extend it with 64-bit time_t, the prototype for sys_newlstat changes.

This changes the initramfs code to use vfs_lstat directly, to get
it out of the way of the time_t changes, and make it slightly more
efficient in the process. Along the same lines we also replace
sys_stat and sys_stat64 with vfs_stat.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
Submitted before in June 2016, but no reply.

Andrew or Al, could one of you pick this up for v4.12?
---
 init/do_mounts.h | 22 ++++------------------
 init/initramfs.c | 12 ++++++------
 2 files changed, 10 insertions(+), 24 deletions(-)

diff --git a/init/do_mounts.h b/init/do_mounts.h
index 067af1d9e8b6..282d65bfd674 100644
--- a/init/do_mounts.h
+++ b/init/do_mounts.h
@@ -19,29 +19,15 @@ static inline int create_dev(char *name, dev_t dev)
 	return sys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));
 }
 
-#if BITS_PER_LONG == 32
 static inline u32 bstat(char *name)
 {
-	struct stat64 stat;
-	if (sys_stat64(name, &stat) != 0)
+	struct kstat stat;
+	if (vfs_stat(name, &stat) != 0)
 		return 0;
-	if (!S_ISBLK(stat.st_mode))
+	if (!S_ISBLK(stat.mode))
 		return 0;
-	if (stat.st_rdev != (u32)stat.st_rdev)
-		return 0;
-	return stat.st_rdev;
-}
-#else
-static inline u32 bstat(char *name)
-{
-	struct stat stat;
-	if (sys_newstat(name, &stat) != 0)
-		return 0;
-	if (!S_ISBLK(stat.st_mode))
-		return 0;
-	return stat.st_rdev;
+	return stat.rdev;
 }
-#endif
 
 #ifdef CONFIG_BLK_DEV_RAM
 
diff --git a/init/initramfs.c b/init/initramfs.c
index 7eb7cb7cb9b9..83d514d0e69d 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -312,10 +312,10 @@ static int __init maybe_link(void)
 
 static void __init clean_path(char *path, umode_t fmode)
 {
-	struct stat st;
+	struct kstat st;
 
-	if (!sys_newlstat(path, &st) && (st.st_mode ^ fmode) & S_IFMT) {
-		if (S_ISDIR(st.st_mode))
+	if (!vfs_lstat(path, &st) && (st.mode ^ fmode) & S_IFMT) {
+		if (S_ISDIR(st.mode))
 			sys_rmdir(path);
 		else
 			sys_unlink(path);
@@ -581,13 +581,13 @@ static void __init clean_rootfs(void)
 	num = sys_getdents64(fd, dirp, BUF_SIZE);
 	while (num > 0) {
 		while (num > 0) {
-			struct stat st;
+			struct kstat st;
 			int ret;
 
-			ret = sys_newlstat(dirp->d_name, &st);
+			ret = vfs_lstat(dirp->d_name, &st);
 			WARN_ON_ONCE(ret);
 			if (!ret) {
-				if (S_ISDIR(st.st_mode))
+				if (S_ISDIR(st.mode))
 					sys_rmdir(dirp->d_name);
 				else
 					sys_unlink(dirp->d_name);
-- 
2.9.0

             reply index

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-14 21:49 Arnd Bergmann [this message]
  -- strict thread matches above, loose matches on Subject: below --
2016-06-17 20:10 Arnd Bergmann

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170314214932.4052842-1-arnd@arndb.de \
    --to=arnd@arndb.de \
    --cc=akpm@linux-foundation.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=viro@zeniv.linux.org.uk \
    --cc=y2038@lists.linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Fsdevel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-fsdevel/0 linux-fsdevel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-fsdevel linux-fsdevel/ https://lore.kernel.org/linux-fsdevel \
		linux-fsdevel@vger.kernel.org linux-fsdevel@archiver.kernel.org
	public-inbox-index linux-fsdevel


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-fsdevel


AGPL code for this site: git clone https://public-inbox.org/ public-inbox