vfs: remove DCACHE_NEED_LOOKUP
Jeff Layton [Wed, 28 Nov 2012 16:30:53 +0000 (11:30 -0500)]
The code that relied on that flag was ripped out of btrfs quite some
time ago, and never added back. Josef indicated that he was going to
take a different approach to the problem in btrfs, and that we
could just eliminate this flag.

Cc: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/btrfs/inode.c
fs/dcache.c
fs/namei.c
include/linux/dcache.h

index 67ed24a..16d9e8e 100644 (file)
@@ -4262,16 +4262,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
        if (dentry->d_name.len > BTRFS_NAME_LEN)
                return ERR_PTR(-ENAMETOOLONG);
 
-       if (unlikely(d_need_lookup(dentry))) {
-               memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key));
-               kfree(dentry->d_fsdata);
-               dentry->d_fsdata = NULL;
-               /* This thing is hashed, drop it for now */
-               d_drop(dentry);
-       } else {
-               ret = btrfs_inode_by_name(dir, dentry, &location);
-       }
-
+       ret = btrfs_inode_by_name(dir, dentry, &location);
        if (ret < 0)
                return ERR_PTR(ret);
 
@@ -4341,11 +4332,6 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
        struct dentry *ret;
 
        ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
-       if (unlikely(d_need_lookup(dentry))) {
-               spin_lock(&dentry->d_lock);
-               dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
-               spin_unlock(&dentry->d_lock);
-       }
        return ret;
 }
 
index 3a463d0..1782be3 100644 (file)
@@ -455,24 +455,6 @@ void d_drop(struct dentry *dentry)
 EXPORT_SYMBOL(d_drop);
 
 /*
- * d_clear_need_lookup - drop a dentry from cache and clear the need lookup flag
- * @dentry: dentry to drop
- *
- * This is called when we do a lookup on a placeholder dentry that needed to be
- * looked up.  The dentry should have been hashed in order for it to be found by
- * the lookup code, but now needs to be unhashed while we do the actual lookup
- * and clear the DCACHE_NEED_LOOKUP flag.
- */
-void d_clear_need_lookup(struct dentry *dentry)
-{
-       spin_lock(&dentry->d_lock);
-       __d_drop(dentry);
-       dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
-       spin_unlock(&dentry->d_lock);
-}
-EXPORT_SYMBOL(d_clear_need_lookup);
-
-/*
  * Finish off a dentry we've decided to kill.
  * dentry->d_lock must be held, returns with it unlocked.
  * If ref is non-zero, then decrement the refcount too.
@@ -565,13 +547,7 @@ repeat:
        if (d_unhashed(dentry))
                goto kill_it;
 
-       /*
-        * If this dentry needs lookup, don't set the referenced flag so that it
-        * is more likely to be cleaned up by the dcache shrinker in case of
-        * memory pressure.
-        */
-       if (!d_need_lookup(dentry))
-               dentry->d_flags |= DCACHE_REFERENCED;
+       dentry->d_flags |= DCACHE_REFERENCED;
        dentry_lru_add(dentry);
 
        dentry->d_count--;
@@ -1737,13 +1713,6 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode,
        }
 
        /*
-        * We are going to instantiate this dentry, unhash it and clear the
-        * lookup flag so we can do that.
-        */
-       if (unlikely(d_need_lookup(found)))
-               d_clear_need_lookup(found);
-
-       /*
         * Negative dentry: instantiate it unless the inode is a directory and
         * already has a dentry.
         */
index 35195ff..25a41e0 100644 (file)
@@ -1275,9 +1275,7 @@ static struct dentry *lookup_dcache(struct qstr *name, struct dentry *dir,
        *need_lookup = false;
        dentry = d_lookup(dir, name);
        if (dentry) {
-               if (d_need_lookup(dentry)) {
-                       *need_lookup = true;
-               } else if (dentry->d_flags & DCACHE_OP_REVALIDATE) {
+               if (dentry->d_flags & DCACHE_OP_REVALIDATE) {
                        error = d_revalidate(dentry, flags);
                        if (unlikely(error <= 0)) {
                                if (error < 0) {
@@ -1383,8 +1381,6 @@ static int lookup_fast(struct nameidata *nd, struct qstr *name,
                        return -ECHILD;
                nd->seq = seq;
 
-               if (unlikely(d_need_lookup(dentry)))
-                       goto unlazy;
                if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) {
                        status = d_revalidate(dentry, nd->flags);
                        if (unlikely(status <= 0)) {
@@ -1410,11 +1406,6 @@ unlazy:
        if (unlikely(!dentry))
                goto need_lookup;
 
-       if (unlikely(d_need_lookup(dentry))) {
-               dput(dentry);
-               goto need_lookup;
-       }
-
        if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval)
                status = d_revalidate(dentry, nd->flags);
        if (unlikely(status <= 0)) {
index 5920079..c1754b5 100644 (file)
@@ -202,7 +202,6 @@ struct dentry_operations {
 #define DCACHE_MOUNTED         0x10000 /* is a mountpoint */
 #define DCACHE_NEED_AUTOMOUNT  0x20000 /* handle automount on this dir */
 #define DCACHE_MANAGE_TRANSIT  0x40000 /* manage transit from this dirent */
-#define DCACHE_NEED_LOOKUP     0x80000 /* dentry requires i_op->lookup */
 #define DCACHE_MANAGED_DENTRY \
        (DCACHE_MOUNTED|DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT)
 
@@ -408,13 +407,6 @@ static inline bool d_mountpoint(struct dentry *dentry)
        return dentry->d_flags & DCACHE_MOUNTED;
 }
 
-static inline bool d_need_lookup(struct dentry *dentry)
-{
-       return dentry->d_flags & DCACHE_NEED_LOOKUP;
-}
-
-extern void d_clear_need_lookup(struct dentry *dentry);
-
 extern int sysctl_vfs_cache_pressure;
 
 #endif /* __LINUX_DCACHE_H */