NFSv4.2: Fix a race in nfs42_proc_deallocate()

When punching holes in a file, we want to ensure the operation is
serialised w.r.t. other writes, meaning that we want to call
nfs_sync_inode() while holding the inode lock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2016-06-25 17:50:53 -04:00
parent 79566ef018
commit 1e564d3dbd
1 changed files with 4 additions and 2 deletions

View File

@ -113,15 +113,17 @@ int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
if (!nfs_server_capable(inode, NFS_CAP_DEALLOCATE))
return -EOPNOTSUPP;
nfs_wb_all(inode);
inode_lock(inode);
err = nfs_sync_inode(inode);
if (err)
goto out_unlock;
err = nfs42_proc_fallocate(&msg, filep, offset, len);
if (err == 0)
truncate_pagecache_range(inode, offset, (offset + len) -1);
if (err == -EOPNOTSUPP)
NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;
out_unlock:
inode_unlock(inode);
return err;
}