autofs4 - remove autofs4_lock

The autofs4_lock introduced by the rcu-walk changes has unnecessarily
broad scope. The locking is better handled by the per-autofs super
block lookup_lock.

Signed-off-by: Ian Kent <raven@themaw.net>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 54f9237..475f9c5 100644 (file)
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -61,8 +61,6 @@ do {                                                  \
                current->pid, __func__, ##args);        \
 } while (0)
 
-extern spinlock_t autofs4_lock;
-
 /* Unified info structure.  This is pointed to by both the dentry and
    inode structures.  Each file in the filesystem has an instance of this
    structure.  It holds a reference to the dentry, so dentries are never

diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index bc482e0..450f529 100644 (file)
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -92,10 +92,11 @@ done:
 static struct dentry *get_next_positive_subdir(struct dentry *prev,
                                                struct dentry *root)
 {
+       struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
        struct list_head *next;
        struct dentry *p, *q;
 
-       spin_lock(&autofs4_lock);
+       spin_lock(&sbi->lookup_lock);
 
        if (prev == NULL) {
                spin_lock(&root->d_lock);
@@ -112,7 +113,7 @@ again:
 start:
        if (next == &root->d_subdirs) {
                spin_unlock(&p->d_lock);
-               spin_unlock(&autofs4_lock);
+               spin_unlock(&sbi->lookup_lock);
                dput(prev);
                return NULL;
        }
@@ -129,7 +130,7 @@ start:
        dget_dlock(q);
        spin_unlock(&q->d_lock);
        spin_unlock(&p->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
 
        dput(prev);
 
@@ -142,13 +143,14 @@ start:
 static struct dentry *get_next_positive_dentry(struct dentry *prev,
                                                struct dentry *root)
 {
+       struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
        struct list_head *next;
        struct dentry *p, *ret;
 
        if (prev == NULL)
                return dget(root);
 
-       spin_lock(&autofs4_lock);
+       spin_lock(&sbi->lookup_lock);
 relock:
        p = prev;
        spin_lock(&p->d_lock);
@@ -160,7 +162,7 @@ again:
 
                        if (p == root) {
                                spin_unlock(&p->d_lock);
-                               spin_unlock(&autofs4_lock);
+                               spin_unlock(&sbi->lookup_lock);
                                dput(prev);
                                return NULL;
                        }
@@ -190,7 +192,7 @@ again:
        dget_dlock(ret);
        spin_unlock(&ret->d_lock);
        spin_unlock(&p->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
 
        dput(prev);
 
@@ -459,13 +461,13 @@ found:
        ino->flags |= AUTOFS_INF_EXPIRING;
        init_completion(&ino->expire_complete);
        spin_unlock(&sbi->fs_lock);
-       spin_lock(&autofs4_lock);
+       spin_lock(&sbi->lookup_lock);
        spin_lock(&expired->d_parent->d_lock);
        spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED);
        list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
        spin_unlock(&expired->d_lock);
        spin_unlock(&expired->d_parent->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
        return expired;
 }
 

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index ebbfa0c..96804a1 100644 (file)
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -23,8 +23,6 @@
 
 #include "autofs_i.h"
 
-DEFINE_SPINLOCK(autofs4_lock);
-
 static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
 static int autofs4_dir_unlink(struct inode *,struct dentry *);
 static int autofs4_dir_rmdir(struct inode *,struct dentry *);
@@ -125,15 +123,15 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
         * autofs file system so just let the libfs routines handle
         * it.
         */
-       spin_lock(&autofs4_lock);
+       spin_lock(&sbi->lookup_lock);
        spin_lock(&dentry->d_lock);
        if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
                spin_unlock(&dentry->d_lock);
-               spin_unlock(&autofs4_lock);
+               spin_unlock(&sbi->lookup_lock);
                return -ENOENT;
        }
        spin_unlock(&dentry->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
 
 out:
        return dcache_dir_open(inode, file);
@@ -171,7 +169,6 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
        const unsigned char *str = name->name;
        struct list_head *p, *head;
 
-       spin_lock(&autofs4_lock);
        spin_lock(&sbi->lookup_lock);
        head = &sbi->active_list;
        list_for_each(p, head) {
@@ -204,14 +201,12 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
                        dget_dlock(active);
                        spin_unlock(&active->d_lock);
                        spin_unlock(&sbi->lookup_lock);
-                       spin_unlock(&autofs4_lock);
                        return active;
                }
 next:
                spin_unlock(&active->d_lock);
        }
        spin_unlock(&sbi->lookup_lock);
-       spin_unlock(&autofs4_lock);
 
        return NULL;
 }
@@ -226,7 +221,6 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
        const unsigned char *str = name->name;
        struct list_head *p, *head;
 
-       spin_lock(&autofs4_lock);
        spin_lock(&sbi->lookup_lock);
        head = &sbi->expiring_list;
        list_for_each(p, head) {
@@ -259,14 +253,12 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
                        dget_dlock(expiring);
                        spin_unlock(&expiring->d_lock);
                        spin_unlock(&sbi->lookup_lock);
-                       spin_unlock(&autofs4_lock);
                        return expiring;
                }
 next:
                spin_unlock(&expiring->d_lock);
        }
        spin_unlock(&sbi->lookup_lock);
-       spin_unlock(&autofs4_lock);
 
        return NULL;
 }
@@ -603,12 +595,12 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 
        dir->i_mtime = CURRENT_TIME;
 
-       spin_lock(&autofs4_lock);
-       autofs4_add_expiring(dentry);
+       spin_lock(&sbi->lookup_lock);
+       __autofs4_add_expiring(dentry);
        spin_lock(&dentry->d_lock);
        __d_drop(dentry);
        spin_unlock(&dentry->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
 
        return 0;
 }
@@ -677,20 +669,17 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
        if (!autofs4_oz_mode(sbi))
                return -EACCES;
 
-       spin_lock(&autofs4_lock);
        spin_lock(&sbi->lookup_lock);
        spin_lock(&dentry->d_lock);
        if (!list_empty(&dentry->d_subdirs)) {
                spin_unlock(&dentry->d_lock);
                spin_unlock(&sbi->lookup_lock);
-               spin_unlock(&autofs4_lock);
                return -ENOTEMPTY;
        }
        __autofs4_add_expiring(dentry);
-       spin_unlock(&sbi->lookup_lock);
        __d_drop(dentry);
        spin_unlock(&dentry->d_lock);
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->lookup_lock);
 
        if (sbi->version < 5)
                autofs_clear_leaf_automount_flags(dentry);

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 5601005..2543598 100644 (file)
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -197,12 +197,12 @@ rename_retry:
 
        seq = read_seqbegin(&rename_lock);
        rcu_read_lock();
-       spin_lock(&autofs4_lock);
+       spin_lock(&sbi->fs_lock);
        for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent)
                len += tmp->d_name.len + 1;
 
        if (!len || --len > NAME_MAX) {
-               spin_unlock(&autofs4_lock);
+               spin_unlock(&sbi->fs_lock);
                rcu_read_unlock();
                if (read_seqretry(&rename_lock, seq))
                        goto rename_retry;
@@ -218,7 +218,7 @@ rename_retry:
                p -= tmp->d_name.len;
                strncpy(p, tmp->d_name.name, tmp->d_name.len);
        }
-       spin_unlock(&autofs4_lock);
+       spin_unlock(&sbi->fs_lock);
        rcu_read_unlock();
        if (read_seqretry(&rename_lock, seq))
                goto rename_retry;