1 files changed, 187 insertions, 83 deletions

diff --git a/fs/inode.c b/fs/inode.c
index 0487ddba1397..bd48e5e6d3e8 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -108,84 +108,102 @@ static void wake_up_inode(struct inode *inode)
         wake_up_bit(&inode->i_state, __I_LOCK);
 }
 
-static struct inode *alloc_inode(struct super_block *sb)
+/**
+ * inode_init_always - perform inode structure intialisation
+ * @sb          - superblock inode belongs to.
+ * @inode       - inode to initialise
+ *
+ * These are initializations that need to be done on every inode
+ * allocation as the fields are not initialised by slab allocation.
+ */
+struct inode *inode_init_always(struct super_block *sb, struct inode *inode)
 {
         static const struct address_space_operations empty_aops;
         static struct inode_operations empty_iops;
         static const struct file_operations empty_fops;
-        struct inode *inode;
 
-        if (sb->s_op->alloc_inode)
-                inode = sb->s_op->alloc_inode(sb);
-        else
-                inode = (struct inode *) kmem_cache_alloc(inode_cachep, GFP_KERNEL);
-
-        if (inode) {
-                struct address_space * const mapping = &inode->i_data;
-
-                inode->i_sb = sb;
-                inode->i_blkbits = sb->s_blocksize_bits;
-                inode->i_flags = 0;
-                atomic_set(&inode->i_count, 1);
-                inode->i_op = &empty_iops;
-                inode->i_fop = &empty_fops;
-                inode->i_nlink = 1;
-                atomic_set(&inode->i_writecount, 0);
-                inode->i_size = 0;
-                inode->i_blocks = 0;
-                inode->i_bytes = 0;
-                inode->i_generation = 0;
+        struct address_space * const mapping = &inode->i_data;
+
+        inode->i_sb = sb;
+        inode->i_blkbits = sb->s_blocksize_bits;
+        inode->i_flags = 0;
+        atomic_set(&inode->i_count, 1);
+        inode->i_op = &empty_iops;
+        inode->i_fop = &empty_fops;
+        inode->i_nlink = 1;
+        inode->i_uid = 0;
+        inode->i_gid = 0;
+        atomic_set(&inode->i_writecount, 0);
+        inode->i_size = 0;
+        inode->i_blocks = 0;
+        inode->i_bytes = 0;
+        inode->i_generation = 0;
 #ifdef CONFIG_QUOTA
-                memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
+        memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
 #endif
-                inode->i_pipe = NULL;
-                inode->i_bdev = NULL;
-                inode->i_cdev = NULL;
-                inode->i_rdev = 0;
-                inode->dirtied_when = 0;
-                if (security_inode_alloc(inode)) {
-                        if (inode->i_sb->s_op->destroy_inode)
-                                inode->i_sb->s_op->destroy_inode(inode);
-                        else
-                                kmem_cache_free(inode_cachep, (inode));
-                        return NULL;
-                }
+        inode->i_pipe = NULL;
+        inode->i_bdev = NULL;
+        inode->i_cdev = NULL;
+        inode->i_rdev = 0;
+        inode->dirtied_when = 0;
+        if (security_inode_alloc(inode)) {
+                if (inode->i_sb->s_op->destroy_inode)
+                        inode->i_sb->s_op->destroy_inode(inode);
+                else
+                        kmem_cache_free(inode_cachep, (inode));
+                return NULL;
+        }
 
-                spin_lock_init(&inode->i_lock);
-                lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
+        spin_lock_init(&inode->i_lock);
+        lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
 
-                mutex_init(&inode->i_mutex);
-                lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
+        mutex_init(&inode->i_mutex);
+        lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
 
-                init_rwsem(&inode->i_alloc_sem);
-                lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key);
+        init_rwsem(&inode->i_alloc_sem);
+        lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key);
 
-                mapping->a_ops = &empty_aops;
-                mapping->host = inode;
-                mapping->flags = 0;
-                mapping_set_gfp_mask(mapping, GFP_HIGHUSER_PAGECACHE);
-                mapping->assoc_mapping = NULL;
-                mapping->backing_dev_info = &default_backing_dev_info;
-                mapping->writeback_index = 0;
+        mapping->a_ops = &empty_aops;
+        mapping->host = inode;
+        mapping->flags = 0;
+        mapping_set_gfp_mask(mapping, GFP_HIGHUSER_PAGECACHE);
+        mapping->assoc_mapping = NULL;
+        mapping->backing_dev_info = &default_backing_dev_info;
+        mapping->writeback_index = 0;
 
-                /*
-                 * If the block_device provides a backing_dev_info for client
-                 * inodes then use that.  Otherwise the inode share the bdev's
-                 * backing_dev_info.
-                 */
-                if (sb->s_bdev) {
-                        struct backing_dev_info *bdi;
+        /*
+         * If the block_device provides a backing_dev_info for client
+         * inodes then use that.  Otherwise the inode share the bdev's
+         * backing_dev_info.
+         */
+        if (sb->s_bdev) {
+                struct backing_dev_info *bdi;
 
-                        bdi = sb->s_bdev->bd_inode_backing_dev_info;
-                        if (!bdi)
-                                bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
-                        mapping->backing_dev_info = bdi;
-                }
-                inode->i_private = NULL;
-                inode->i_mapping = mapping;
+                bdi = sb->s_bdev->bd_inode_backing_dev_info;
+                if (!bdi)
+                        bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
+                mapping->backing_dev_info = bdi;
         }
+        inode->i_private = NULL;
+        inode->i_mapping = mapping;
+
         return inode;
 }
+EXPORT_SYMBOL(inode_init_always);
+
+static struct inode *alloc_inode(struct super_block *sb)
+{
+        struct inode *inode;
+
+        if (sb->s_op->alloc_inode)
+                inode = sb->s_op->alloc_inode(sb);
+        else
+                inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL);
+
+        if (inode)
+                return inode_init_always(sb, inode);
+        return NULL;
+}
 
 void destroy_inode(struct inode *inode) 
 {
@@ -196,6 +214,7 @@ void destroy_inode(struct inode *inode)
         else
                 kmem_cache_free(inode_cachep, (inode));
 }
+EXPORT_SYMBOL(destroy_inode);
 
 
 /*
@@ -534,6 +553,49 @@ repeat:
         return node ? inode : NULL;
 }
 
+static unsigned long hash(struct super_block *sb, unsigned long hashval)
+{
+        unsigned long tmp;
+
+        tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) /
+                        L1_CACHE_BYTES;
+        tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> I_HASHBITS);
+        return tmp & I_HASHMASK;
+}
+
+static inline void
+__inode_add_to_lists(struct super_block *sb, struct hlist_head *head,
+                        struct inode *inode)
+{
+        inodes_stat.nr_inodes++;
+        list_add(&inode->i_list, &inode_in_use);
+        list_add(&inode->i_sb_list, &sb->s_inodes);
+        if (head)
+                hlist_add_head(&inode->i_hash, head);
+}
+
+/**
+ * inode_add_to_lists - add a new inode to relevant lists
+ * @sb          - superblock inode belongs to.
+ * @inode       - inode to mark in use
+ *
+ * When an inode is allocated it needs to be accounted for, added to the in use
+ * list, the owning superblock and the inode hash. This needs to be done under
+ * the inode_lock, so export a function to do this rather than the inode lock
+ * itself. We calculate the hash list to add to here so it is all internal
+ * which requires the caller to have already set up the inode number in the
+ * inode to add.
+ */
+void inode_add_to_lists(struct super_block *sb, struct inode *inode)
+{
+        struct hlist_head *head = inode_hashtable + hash(sb, inode->i_ino);
+
+        spin_lock(&inode_lock);
+        __inode_add_to_lists(sb, head, inode);
+        spin_unlock(&inode_lock);
+}
+EXPORT_SYMBOL_GPL(inode_add_to_lists);
+
 /**
  *      new_inode       - obtain an inode
  *      @sb: superblock
@@ -561,9 +623,7 @@ struct inode *new_inode(struct super_block *sb)
         inode = alloc_inode(sb);
         if (inode) {
                 spin_lock(&inode_lock);
-                inodes_stat.nr_inodes++;
-                list_add(&inode->i_list, &inode_in_use);
-                list_add(&inode->i_sb_list, &sb->s_inodes);
+                __inode_add_to_lists(sb, NULL, inode);
                 inode->i_ino = ++last_ino;
                 inode->i_state = 0;
                 spin_unlock(&inode_lock);
@@ -622,10 +682,7 @@ static struct inode * get_new_inode(struct super_block *sb, struct hlist_head *h
                         if (set(inode, data))
                                 goto set_failed;
 
-                        inodes_stat.nr_inodes++;
-                        list_add(&inode->i_list, &inode_in_use);
-                        list_add(&inode->i_sb_list, &sb->s_inodes);
-                        hlist_add_head(&inode->i_hash, head);
+                        __inode_add_to_lists(sb, head, inode);
                         inode->i_state = I_LOCK|I_NEW;
                         spin_unlock(&inode_lock);
 
@@ -671,10 +728,7 @@ static struct inode * get_new_inode_fast(struct super_block *sb, struct hlist_he
                 old = find_inode_fast(sb, head, ino);
                 if (!old) {
                         inode->i_ino = ino;
-                        inodes_stat.nr_inodes++;
-                        list_add(&inode->i_list, &inode_in_use);
-                        list_add(&inode->i_sb_list, &sb->s_inodes);
-                        hlist_add_head(&inode->i_hash, head);
+                        __inode_add_to_lists(sb, head, inode);
                         inode->i_state = I_LOCK|I_NEW;
                         spin_unlock(&inode_lock);
 
@@ -698,16 +752,6 @@ static struct inode * get_new_inode_fast(struct super_block *sb, struct hlist_he
         return inode;
 }
 
-static unsigned long hash(struct super_block *sb, unsigned long hashval)
-{
-        unsigned long tmp;
-
-        tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) /
-                        L1_CACHE_BYTES;
-        tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> I_HASHBITS);
-        return tmp & I_HASHMASK;
-}
-
 /**
  *      iunique - get a unique inode number
  *      @sb: superblock
@@ -990,6 +1034,65 @@ struct inode *iget_locked(struct super_block *sb, unsigned long ino)
 
 EXPORT_SYMBOL(iget_locked);
 
+int insert_inode_locked(struct inode *inode)
+{
+        struct super_block *sb = inode->i_sb;
+        ino_t ino = inode->i_ino;
+        struct hlist_head *head = inode_hashtable + hash(sb, ino);
+        struct inode *old;
+
+        inode->i_state |= I_LOCK|I_NEW;
+        while (1) {
+                spin_lock(&inode_lock);
+                old = find_inode_fast(sb, head, ino);
+                if (likely(!old)) {
+                        hlist_add_head(&inode->i_hash, head);
+                        spin_unlock(&inode_lock);
+                        return 0;
+                }
+                __iget(old);
+                spin_unlock(&inode_lock);
+                wait_on_inode(old);
+                if (unlikely(!hlist_unhashed(&old->i_hash))) {
+                        iput(old);
+                        return -EBUSY;
+                }
+                iput(old);
+        }
+}
+
+EXPORT_SYMBOL(insert_inode_locked);
+
+int insert_inode_locked4(struct inode *inode, unsigned long hashval,
+                int (*test)(struct inode *, void *), void *data)
+{
+        struct super_block *sb = inode->i_sb;
+        struct hlist_head *head = inode_hashtable + hash(sb, hashval);
+        struct inode *old;
+
+        inode->i_state |= I_LOCK|I_NEW;
+
+        while (1) {
+                spin_lock(&inode_lock);
+                old = find_inode(sb, head, test, data);
+                if (likely(!old)) {
+                        hlist_add_head(&inode->i_hash, head);
+                        spin_unlock(&inode_lock);
+                        return 0;
+                }
+                __iget(old);
+                spin_unlock(&inode_lock);
+                wait_on_inode(old);
+                if (unlikely(!hlist_unhashed(&old->i_hash))) {
+                        iput(old);
+                        return -EBUSY;
+                }
+                iput(old);
+        }
+}
+
+EXPORT_SYMBOL(insert_inode_locked4);
+
 /**
  *      __insert_inode_hash - hash an inode
  *      @inode: unhashed inode
@@ -1292,6 +1395,7 @@ int inode_wait(void *word)
         schedule();
         return 0;
 }
+EXPORT_SYMBOL(inode_wait);
 
 /*
  * If we try to find an inode in the inode hash while it is being