Make FAT users happier by not deadlocking

The FAT BKL removal patch can cause deadlocks.  It turns out that the new
lock_super() calls are unneeded, remove them (as directed by Linus).

Reported-by: "Tony Luck" <tony.luck@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/fs/fat/file.c b/fs/fat/file.c
index 7059928fb351aededd9198350ec1b54be60c785c..bdf91e97397df7e4b26ba4bb8e03637854cb8228 100644 (file)
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -11,7 +11,6 @@
 #include <linux/mount.h>
 #include <linux/time.h>
 #include <linux/msdos_fs.h>
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
@@ -229,8 +228,7 @@ static int fat_free(struct inode *inode, int skip)
 
 void fat_truncate(struct inode *inode)
 {
-       struct super_block *sb = inode->i_sb;
-       struct msdos_sb_info *sbi = MSDOS_SB(sb);
+       struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
        const unsigned int cluster_size = sbi->cluster_size;
        int nr_clusters;
 
@@ -243,9 +241,7 @@ void fat_truncate(struct inode *inode)
 
        nr_clusters = (inode->i_size + (cluster_size - 1)) >> sbi->cluster_bits;
 
-       lock_super(sb);
        fat_free(inode, nr_clusters);
-       unlock_super(sb);
        fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
@@ -298,14 +294,11 @@ static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
 
 int fat_setattr(struct dentry *dentry, struct iattr *attr)
 {
-       struct super_block *sb = dentry->d_sb;
        struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
        struct inode *inode = dentry->d_inode;
        int mask, error = 0;
        unsigned int ia_valid;
 
-       lock_super(sb);
-
        /*
         * Expand the file. Since inode_setattr() updates ->i_size
         * before calling the ->truncate(), but FAT needs to fill the
@@ -358,7 +351,6 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
                mask = sbi->options.fs_fmask;
        inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask);
 out:
-       unlock_super(sb);
        return error;
 }
 EXPORT_SYMBOL_GPL(fat_setattr);