Ensure no new files will be added when we're inspecting 'all' files. Without this, files could be added in front while we're iterating and we'd miss those. Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- fs/file_table.c | 9 +++++++++ fs/super.c | 3 +++ include/linux/fs.h | 2 ++ security/selinux/selinuxfs.c | 7 ++++--- 4 files changed, 18 insertions(+), 3 deletions(-) Index: linux-2.6/fs/file_table.c =================================================================== --- linux-2.6.orig/fs/file_table.c 2007-01-27 21:07:44.000000000 +0100 +++ linux-2.6/fs/file_table.c 2007-01-27 21:11:12.000000000 +0100 @@ -354,6 +354,12 @@ EXPORT_SYMBOL_GPL(filevec_add_drain_all) void file_kill(struct file *file) { + if (file && file->f_mapping && file->f_mapping->host) { + struct super_block *sb = file->f_mapping->host->i_sb; + if (sb) + barrier_sync(&sb->s_barrier); + } + if (file_flag(file, F_SUPERBLOCK)) { void **ptr; @@ -412,6 +418,7 @@ int fs_may_remount_ro(struct super_block struct file *file; /* Check that no files are currently opened for writing. */ + barrier_lock(&sb->s_barrier); filevec_add_drain_all(); lock_list_for_each_entry(file, &sb->s_files, f_u.fu_llist) { struct inode *inode = file->f_path.dentry->d_inode; @@ -424,9 +431,11 @@ int fs_may_remount_ro(struct super_block if (S_ISREG(inode->i_mode) && (file->f_mode & FMODE_WRITE)) goto too_bad; } + barrier_unlock(&sb->s_barrier); return 1; /* Tis' cool bro. */ too_bad: lock_list_for_each_entry_stop(file, f_u.fu_llist); + barrier_unlock(&sb->s_barrier); return 0; } Index: linux-2.6/fs/super.c =================================================================== --- linux-2.6.orig/fs/super.c 2007-01-27 21:07:44.000000000 +0100 +++ linux-2.6/fs/super.c 2007-01-27 21:11:12.000000000 +0100 @@ -68,6 +68,7 @@ static struct super_block *alloc_super(s INIT_LIST_HEAD(&s->s_dirty); INIT_LIST_HEAD(&s->s_io); INIT_LOCK_LIST_HEAD(&s->s_files); + init_barrier(&s->s_barrier); INIT_LIST_HEAD(&s->s_instances); INIT_HLIST_HEAD(&s->s_anon); INIT_LIST_HEAD(&s->s_inodes); @@ -568,11 +569,13 @@ static void mark_files_ro(struct super_b { struct file *f; + barrier_lock(&sb->s_barrier); filevec_add_drain_all(); lock_list_for_each_entry(f, &sb->s_files, f_u.fu_llist) { if (S_ISREG(f->f_path.dentry->d_inode->i_mode) && file_count(f)) f->f_mode &= ~FMODE_WRITE; } + barrier_unlock(&sb->s_barrier); } /** Index: linux-2.6/include/linux/fs.h =================================================================== --- linux-2.6.orig/include/linux/fs.h 2007-01-27 21:07:44.000000000 +0100 +++ linux-2.6/include/linux/fs.h 2007-01-27 21:11:12.000000000 +0100 @@ -281,6 +281,7 @@ extern int dir_notify_enable; #include #include #include +#include #include #include @@ -950,6 +951,7 @@ struct super_block { struct list_head s_io; /* parked for writeback */ struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */ struct lock_list_head s_files; + struct barrier s_barrier; struct block_device *s_bdev; struct list_head s_instances; Index: linux-2.6/security/selinux/selinuxfs.c =================================================================== --- linux-2.6.orig/security/selinux/selinuxfs.c 2007-01-27 21:10:48.000000000 +0100 +++ linux-2.6/security/selinux/selinuxfs.c 2007-01-27 21:11:40.000000000 +0100 @@ -963,6 +963,7 @@ static void sel_remove_bools(struct dent spin_unlock(&dcache_lock); + barrier_lock(&sb->s_barrier); filevec_add_drain_all(); lock_list_for_each_entry(filp, &sb->s_files, f_u.fu_llist) { struct dentry * dentry = filp->f_path.dentry; @@ -972,6 +973,7 @@ static void sel_remove_bools(struct dent } filp->f_op = NULL; } + barrier_unlock(&sb->s_barrier); } #define BOOL_DIR_NAME "booleans" -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/