Merge branch 'for-3.20/bdi' of git://git.kernel.dk/linux-block

Pull backing device changes from Jens Axboe:
 "This contains a cleanup of how the backing device is handled, in
  preparation for a rework of the life time rules.  In this part, the
  most important change is to split the unrelated nommu mmap flags from
  it, but also removing a backing_dev_info pointer from the
  address_space (and inode), and a cleanup of other various minor bits.

  Christoph did all the work here, I just fixed an oops with pages that
  have a swap backing.  Arnd fixed a missing export, and Oleg killed the
  lustre backing_dev_info from staging.  Last patch was from Al,
  unexporting parts that are now no longer needed outside"

* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
  Make super_blocks and sb_lock static
  mtd: export new mtd_mmap_capabilities
  fs: make inode_to_bdi() handle NULL inode
  staging/lustre/llite: get rid of backing_dev_info
  fs: remove default_backing_dev_info
  fs: don't reassign dirty inodes to default_backing_dev_info
  nfs: don't call bdi_unregister
  ceph: remove call to bdi_unregister
  fs: remove mapping->backing_dev_info
  fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
  nilfs2: set up s_bdi like the generic mount_bdev code
  block_dev: get bdev inode bdi directly from the block device
  block_dev: only write bdev inode on close
  fs: introduce f_op->mmap_capabilities for nommu mmap support
  fs: kill BDI_CAP_SWAP_BACKED
  fs: deduplicate noop_backing_dev_info

1 files changed, 5 insertions, 7 deletions

diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index cee02d65ab3f..0e9310905413 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -47,7 +47,7 @@ TRACE_EVENT(writeback_dirty_page,
 
         TP_fast_assign(
                 strncpy(__entry->name,
-                        mapping ? dev_name(mapping->backing_dev_info->dev) : "(unknown)", 32);
+                        mapping ? dev_name(inode_to_bdi(mapping->host)->dev) : "(unknown)", 32);
                 __entry->ino = mapping ? mapping->host->i_ino : 0;
                 __entry->index = page->index;
         ),
@@ -72,7 +72,7 @@ DECLARE_EVENT_CLASS(writeback_dirty_inode_template,
         ),
 
         TP_fast_assign(
-                struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
+                struct backing_dev_info *bdi = inode_to_bdi(inode);
 
                 /* may be called for files on pseudo FSes w/ unregistered bdi */
                 strncpy(__entry->name,
@@ -116,7 +116,7 @@ DECLARE_EVENT_CLASS(writeback_write_inode_template,
 
         TP_fast_assign(
                 strncpy(__entry->name,
-                        dev_name(inode->i_mapping->backing_dev_info->dev), 32);
+                        dev_name(inode_to_bdi(inode)->dev), 32);
                 __entry->ino            = inode->i_ino;
                 __entry->sync_mode      = wbc->sync_mode;
         ),
@@ -156,10 +156,8 @@ DECLARE_EVENT_CLASS(writeback_work_class,
                 __field(int, reason)
         ),
         TP_fast_assign(
-                struct device *dev = bdi->dev;
-                if (!dev)
-                        dev = default_backing_dev_info.dev;
-                strncpy(__entry->name, dev_name(dev), 32);
+                strncpy(__entry->name,
+                        bdi->dev ? dev_name(bdi->dev) : "(unknown)", 32);
                 __entry->nr_pages = work->nr_pages;
                 __entry->sb_dev = work->sb ? work->sb->s_dev : 0;
                 __entry->sync_mode = work->sync_mode;