bdev: get rid of ->bd_inodes

Since 2006 we have ->i_bdev pinning bdev in question, so there's no
way to get to bdev ->evict_inode() while there's an aliasing inode
anywhere.  In other words, the only place walking the list of aliases
is guaranteed to do it only when the list is empty...

Remove the detritus; it should've been done in "[PATCH] Fix a race
condition between ->i_mapping and iput()", but nobody had noticed it
back then.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 71ccab1..73130da 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -614,7 +614,6 @@ static void init_once(void *foo)
 
        memset(bdev, 0, sizeof(*bdev));
        mutex_init(&bdev->bd_mutex);
-       INIT_LIST_HEAD(&bdev->bd_inodes);
        INIT_LIST_HEAD(&bdev->bd_list);
 #ifdef CONFIG_SYSFS
        INIT_LIST_HEAD(&bdev->bd_holder_disks);
@@ -624,24 +623,13 @@ static void init_once(void *foo)
        mutex_init(&bdev->bd_fsfreeze_mutex);
 }
 
-static inline void __bd_forget(struct inode *inode)
-{
-       list_del_init(&inode->i_devices);
-       inode->i_bdev = NULL;
-       inode->i_mapping = &inode->i_data;
-}
-
 static void bdev_evict_inode(struct inode *inode)
 {
        struct block_device *bdev = &BDEV_I(inode)->bdev;
-       struct list_head *p;
        truncate_inode_pages_final(&inode->i_data);
        invalidate_inode_buffers(inode); /* is it needed here? */
        clear_inode(inode);
        spin_lock(&bdev_lock);
-       while ( (p = bdev->bd_inodes.next) != &bdev->bd_inodes ) {
-               __bd_forget(list_entry(p, struct inode, i_devices));
-       }
        list_del_init(&bdev->bd_list);
        spin_unlock(&bdev_lock);
 }
@@ -805,7 +793,6 @@ static struct block_device *bd_acquire(struct inode *inode)
                        bdgrab(bdev);
                        inode->i_bdev = bdev;
                        inode->i_mapping = bdev->bd_inode->i_mapping;
-                       list_add(&inode->i_devices, &bdev->bd_inodes);
                }
                spin_unlock(&bdev_lock);
        }
@@ -821,7 +808,8 @@ void bd_forget(struct inode *inode)
        spin_lock(&bdev_lock);
        if (!sb_is_blkdev_sb(inode->i_sb))
                bdev = inode->i_bdev;
-       __bd_forget(inode);
+       inode->i_bdev = NULL;
+       inode->i_mapping = &inode->i_data;
        spin_unlock(&bdev_lock);
 
        if (bdev)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index bacc073..1878c84 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -459,7 +459,6 @@ struct block_device {
        struct inode *          bd_inode;       /* will die */
        struct super_block *    bd_super;
        struct mutex            bd_mutex;       /* open/close mutex */
-       struct list_head        bd_inodes;
        void *                  bd_claiming;
        void *                  bd_holder;
        int                     bd_holders;