[PATCH 3.16 044/366] ext4: factor out helper ext4_sample_last_mounted()

From: Ben Hutchings
Date: Sun Nov 11 2018 - 15:07:42 EST


3.16.61-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Amir Goldstein <amir73il@xxxxxxxxx>

commit 833a950882d33a7dfc319d5e152fdf35028936eb upstream.

Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
[bwh: Backported to 3.16:
- Move up declaration of ret in ext4_file_open()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
fs/ext4/file.c | 82 ++++++++++++++++++++++++++++----------------------
1 file changed, 46 insertions(+), 36 deletions(-)

--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -208,52 +208,64 @@ static int ext4_file_mmap(struct file *f
return 0;
}

-static int ext4_file_open(struct inode * inode, struct file * filp)
+static int ext4_sample_last_mounted(struct super_block *sb,
+ struct vfsmount *mnt)
{
- struct super_block *sb = inode->i_sb;
- struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
- struct vfsmount *mnt = filp->f_path.mnt;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
struct path path;
char buf[64], *cp;
+ handle_t *handle;
+ int err;
+
+ if (likely(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED))
+ return 0;
+
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+
+ sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
+ /*
+ * Sample where the filesystem has been mounted and
+ * store it in the superblock for sysadmin convenience
+ * when trying to sort through large numbers of block
+ * devices or filesystem images.
+ */
+ memset(buf, 0, sizeof(buf));
+ path.mnt = mnt;
+ path.dentry = mnt->mnt_root;
+ cp = d_path(&path, buf, sizeof(buf));
+ if (IS_ERR(cp))
+ return 0;
+
+ handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ BUFFER_TRACE(sbi->s_sbh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sbi->s_sbh);
+ if (err)
+ goto out;
+ strlcpy(sbi->s_es->s_last_mounted, cp,
+ sizeof(sbi->s_es->s_last_mounted));
+ ext4_handle_dirty_super(handle, sb);
+out:
+ ext4_journal_stop(handle);
+ return err;
+}
+
+static int ext4_file_open(struct inode * inode, struct file * filp)
+{
+ int ret;
+
+ ret = ext4_sample_last_mounted(inode->i_sb, filp->f_path.mnt);
+ if (ret)
+ return ret;

- if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) &&
- !(sb->s_flags & MS_RDONLY))) {
- sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
- /*
- * Sample where the filesystem has been mounted and
- * store it in the superblock for sysadmin convenience
- * when trying to sort through large numbers of block
- * devices or filesystem images.
- */
- memset(buf, 0, sizeof(buf));
- path.mnt = mnt;
- path.dentry = mnt->mnt_root;
- cp = d_path(&path, buf, sizeof(buf));
- if (!IS_ERR(cp)) {
- handle_t *handle;
- int err;
-
- handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
- if (IS_ERR(handle))
- return PTR_ERR(handle);
- BUFFER_TRACE(sbi->s_sbh, "get_write_access");
- err = ext4_journal_get_write_access(handle, sbi->s_sbh);
- if (err) {
- ext4_journal_stop(handle);
- return err;
- }
- strlcpy(sbi->s_es->s_last_mounted, cp,
- sizeof(sbi->s_es->s_last_mounted));
- ext4_handle_dirty_super(handle, sb);
- ext4_journal_stop(handle);
- }
- }
/*
* Set up the jbd2_inode if we are opening the inode for
* writing and the journal is present
*/
if (filp->f_mode & FMODE_WRITE) {
- int ret = ext4_inode_attach_jinode(inode);
+ ret = ext4_inode_attach_jinode(inode);
if (ret < 0)
return ret;
}