[PATCH] BUGFIX: Ext2/3 noatime and dirsync sometimes ignored

From: Theodore Ts'o (tytso@mit.edu)
Date: Thu Mar 13 2003 - 03:48:31 EST


I recently noticed a bug in ext2/3; newly created inodes which inherit
the noatime flag from their containing directory do not respect noatime
until the inode is flushed from the inode cache and then re-read later.
This is because the code which checks the ext2 no-atime attribute and
then sets the S_NOATIME in inode->i_flags is present in
ext2_read_inode(), but not in ext2_new_inode().

I fixed this in 2.4, and then found an even worse bug in the 2.5 code;
the DIRSYNC flag is completely ignored *except* in the case where a
directory is newly created using mkdir and its parent directory has the
DIRSYNC flag. S_DIRSYNC doesn't get set in the ext2_new_inode() or the
ext2_ioctl() paths (which is used by chattr).

This patch centralizes the code which translates the ext2 flags in the
raw ext2 inode to the appropriate flag values in inode->i_flags in a
single location. This fixes the bug, makes things cleaner, and also
removes 30 lines of code and 128 bytes of compiled x86 text in the
bargain.

                                                - Ted

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
#
# This patch includes the following deltas:
# fs/ext2/ext2.h | 1 +
# fs/ext2/ialloc.c | 5 +----
# fs/ext2/inode.c | 26 ++++++++++++++++++--------
# fs/ext2/ioctl.c | 17 +----------------
# fs/ext3/ialloc.c | 5 +----
# fs/ext3/inode.c | 27 +++++++++++++++++++--------
# fs/ext3/ioctl.c | 17 +----------------
# include/linux/ext3_fs.h | 1 +
# 8 files changed, 43 insertions(+), 56 deletions(-)
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 tytso@think.thunk.org 1.1101
# Centralize setting inode flags from the raw ext2/3 inode
#
# This fixes a bug where the noatime flag not being honored in inodes
# which inherited noatime from their directory flag (at least not until
# inode was flushed out of the inode cache and then re-read into the inode
# cache later on), and also saves code because the common code has all been
# factored out.
#
# This also fixes an even worse bug with DIRSYNC; it was only being
# honored for newly created directories which inherited the DIRSYNC
# attribute. Pre-existing directories which were read using
# ext2_read_inode or which had the DIRSYNC attribute set via chattr
# did not have S_DIRSYNC set in inode->i_flags so the DIRSYNC attribute
# was getting ignored!
# --------------------------------------------
#
diff -Nru a/fs/ext2/ext2.h b/fs/ext2/ext2.h
--- a/fs/ext2/ext2.h Thu Mar 13 03:39:59 2003
+++ b/fs/ext2/ext2.h Thu Mar 13 03:39:59 2003
@@ -112,6 +112,7 @@
 extern void ext2_discard_prealloc (struct inode *);
 extern void ext2_truncate (struct inode *);
 extern int ext2_setattr (struct dentry *, struct iattr *);
+extern void ext2_set_inode_flags(struct inode *inode);
 
 /* ioctl.c */
 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
diff -Nru a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
--- a/fs/ext2/ialloc.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext2/ialloc.c Thu Mar 13 03:39:59 2003
@@ -545,10 +545,7 @@
         ei->i_prealloc_count = 0;
         ei->i_dir_start_lookup = 0;
         ei->i_state = EXT2_STATE_NEW;
- if (ei->i_flags & EXT2_SYNC_FL)
- inode->i_flags |= S_SYNC;
- if (ei->i_flags & EXT2_DIRSYNC_FL)
- inode->i_flags |= S_DIRSYNC;
+ ext2_set_inode_flags(inode);
         inode->i_generation = EXT2_SB(sb)->s_next_generation++;
         insert_inode_hash(inode);
 
diff -Nru a/fs/ext2/inode.c b/fs/ext2/inode.c
--- a/fs/ext2/inode.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext2/inode.c Thu Mar 13 03:39:59 2003
@@ -1011,6 +1011,23 @@
         return ERR_PTR(-EIO);
 }
 
+void ext2_set_inode_flags(struct inode *inode)
+{
+ unsigned int flags = EXT2_I(inode)->i_flags;
+
+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+ if (flags & EXT2_SYNC_FL)
+ inode->i_flags |= S_SYNC;
+ if (flags & EXT2_APPEND_FL)
+ inode->i_flags |= S_APPEND;
+ if (flags & EXT2_IMMUTABLE_FL)
+ inode->i_flags |= S_IMMUTABLE;
+ if (flags & EXT2_NOATIME_FL)
+ inode->i_flags |= S_NOATIME;
+ if (flags & EXT2_DIRSYNC_FL)
+ inode->i_flags |= S_DIRSYNC;
+}
+
 void ext2_read_inode (struct inode * inode)
 {
         struct ext2_inode_info *ei = EXT2_I(inode);
@@ -1108,14 +1125,7 @@
                                    le32_to_cpu(raw_inode->i_block[0]));
         }
         brelse (bh);
- if (ei->i_flags & EXT2_SYNC_FL)
- inode->i_flags |= S_SYNC;
- if (ei->i_flags & EXT2_APPEND_FL)
- inode->i_flags |= S_APPEND;
- if (ei->i_flags & EXT2_IMMUTABLE_FL)
- inode->i_flags |= S_IMMUTABLE;
- if (ei->i_flags & EXT2_NOATIME_FL)
- inode->i_flags |= S_NOATIME;
+ ext2_set_inode_flags(inode);
         return;
         
 bad_inode:
diff -Nru a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
--- a/fs/ext2/ioctl.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext2/ioctl.c Thu Mar 13 03:39:59 2003
@@ -58,22 +58,7 @@
                 flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
                 ei->i_flags = flags;
 
- if (flags & EXT2_SYNC_FL)
- inode->i_flags |= S_SYNC;
- else
- inode->i_flags &= ~S_SYNC;
- if (flags & EXT2_APPEND_FL)
- inode->i_flags |= S_APPEND;
- else
- inode->i_flags &= ~S_APPEND;
- if (flags & EXT2_IMMUTABLE_FL)
- inode->i_flags |= S_IMMUTABLE;
- else
- inode->i_flags &= ~S_IMMUTABLE;
- if (flags & EXT2_NOATIME_FL)
- inode->i_flags |= S_NOATIME;
- else
- inode->i_flags &= ~S_NOATIME;
+ ext2_set_inode_flags(inode);
                 inode->i_ctime = CURRENT_TIME;
                 mark_inode_dirty(inode);
                 return 0;
diff -Nru a/fs/ext3/ialloc.c b/fs/ext3/ialloc.c
--- a/fs/ext3/ialloc.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext3/ialloc.c Thu Mar 13 03:39:59 2003
@@ -568,10 +568,7 @@
 #endif
         ei->i_block_group = group;
         
- if (ei->i_flags & EXT3_SYNC_FL)
- inode->i_flags |= S_SYNC;
- if (ei->i_flags & EXT3_DIRSYNC_FL)
- inode->i_flags |= S_DIRSYNC;
+ ext3_set_inode_flags(inode);
         if (IS_DIRSYNC(inode))
                 handle->h_sync = 1;
         insert_inode_hash(inode);
diff -Nru a/fs/ext3/inode.c b/fs/ext3/inode.c
--- a/fs/ext3/inode.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext3/inode.c Thu Mar 13 03:39:59 2003
@@ -2209,6 +2209,24 @@
         return -EIO;
 }
 
+void ext3_set_inode_flags(struct inode *inode)
+{
+ unsigned int flags = EXT3_I(inode)->i_flags;
+
+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+ if (flags & EXT3_SYNC_FL)
+ inode->i_flags |= S_SYNC;
+ if (flags & EXT3_APPEND_FL)
+ inode->i_flags |= S_APPEND;
+ if (flags & EXT3_IMMUTABLE_FL)
+ inode->i_flags |= S_IMMUTABLE;
+ if (flags & EXT3_NOATIME_FL)
+ inode->i_flags |= S_NOATIME;
+ if (flags & EXT3_DIRSYNC_FL)
+ inode->i_flags |= S_DIRSYNC;
+}
+
+
 void ext3_read_inode(struct inode * inode)
 {
         struct ext3_iloc iloc;
@@ -2320,14 +2338,7 @@
                 init_special_inode(inode, inode->i_mode,
                                    le32_to_cpu(iloc.raw_inode->i_block[0]));
         }
- if (ei->i_flags & EXT3_SYNC_FL)
- inode->i_flags |= S_SYNC;
- if (ei->i_flags & EXT3_APPEND_FL)
- inode->i_flags |= S_APPEND;
- if (ei->i_flags & EXT3_IMMUTABLE_FL)
- inode->i_flags |= S_IMMUTABLE;
- if (ei->i_flags & EXT3_NOATIME_FL)
- inode->i_flags |= S_NOATIME;
+ ext3_set_inode_flags(inode);
         return;
         
 bad_inode:
diff -Nru a/fs/ext3/ioctl.c b/fs/ext3/ioctl.c
--- a/fs/ext3/ioctl.c Thu Mar 13 03:39:59 2003
+++ b/fs/ext3/ioctl.c Thu Mar 13 03:39:59 2003
@@ -85,22 +85,7 @@
                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
                 ei->i_flags = flags;
 
- if (flags & EXT3_SYNC_FL)
- inode->i_flags |= S_SYNC;
- else
- inode->i_flags &= ~S_SYNC;
- if (flags & EXT3_APPEND_FL)
- inode->i_flags |= S_APPEND;
- else
- inode->i_flags &= ~S_APPEND;
- if (flags & EXT3_IMMUTABLE_FL)
- inode->i_flags |= S_IMMUTABLE;
- else
- inode->i_flags &= ~S_IMMUTABLE;
- if (flags & EXT3_NOATIME_FL)
- inode->i_flags |= S_NOATIME;
- else
- inode->i_flags &= ~S_NOATIME;
+ ext3_set_inode_flags(inode);
                 inode->i_ctime = CURRENT_TIME;
 
                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
diff -Nru a/include/linux/ext3_fs.h b/include/linux/ext3_fs.h
--- a/include/linux/ext3_fs.h Thu Mar 13 03:39:59 2003
+++ b/include/linux/ext3_fs.h Thu Mar 13 03:39:59 2003
@@ -730,6 +730,7 @@
 extern void ext3_dirty_inode(struct inode *);
 extern int ext3_change_inode_journal_flag(struct inode *, int);
 extern void ext3_truncate (struct inode *);
+extern void ext3_set_inode_flags(struct inode *);
 
 /* ioctl.c */
 extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
-
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This archive was generated by hypermail 2b29 : Sat Mar 15 2003 - 22:00:34 EST