NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code
Move more pnfs-isms out of the generic commit code.
Bugfixes:
- filelayout_scan_commit_lists doesn't need to get/put the lseg.
In fact since it is run under the inode->i_lock, the lseg_put()
can deadlock.
- Ensure that we distinguish between what needs to be done for
commit-to-data server and what needs to be done for commit-to-MDS
using the new flag PG_COMMIT_TO_DS. Otherwise we may end up calling
put_lseg() on a bucket for a struct nfs_page that got written
through the MDS.
- Fix a case where we were using list_del() on an nfs_page->wb_list
instead of list_del_init().
- filelayout_initiate_commit needs to call filelayout_commit_release
on error instead of the mds_ops->rpc_release(). Otherwise it won't
clear the commit lock.
Cleanups:
- Let the files layout manage the commit lists for the pNFS case.
Don't expose stuff like pnfs_choose_commit_list, and the fact
that the commit buckets hold references to the layout segment
in common code.
- Cast out the put_lseg() calls for the struct nfs_read/write_data->lseg
into the pNFS layer from whence they came.
- Let the pNFS layer manage the NFS_INO_PNFS_COMMIT bit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 50856e9..eac30d6 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -28,6 +28,7 @@
PG_NEED_COMMIT,
PG_NEED_RESCHED,
PG_PARTIAL_READ_FAILED,
+ PG_COMMIT_TO_DS,
};
struct nfs_inode;
@@ -104,6 +105,16 @@
return !test_and_set_bit(PG_BUSY, &req->wb_flags);
}
+static inline int
+nfs_lock_request(struct nfs_page *req)
+{
+ if (test_and_set_bit(PG_BUSY, &req->wb_flags))
+ return 0;
+ kref_get(&req->wb_kref);
+ return 1;
+}
+
+
/**
* nfs_list_add_request - Insert a request into a list
* @req: request