The VFS handles attributes on truncate in a strange way, fix NFS to handle
it properly by copying a small code sniplet from XFS.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/nfs/inode.c | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 577a36f..5bbd991 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -505,8 +505,28 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
attr->ia_valid &= ~ATTR_MODE;
if (attr->ia_valid & ATTR_SIZE) {
- if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
+ if (!S_ISREG(inode->i_mode) ||
+ attr->ia_size == i_size_read(inode))
attr->ia_valid &= ~ATTR_SIZE;
+
+ /*
+ * Only change the c/mtime if we are changing the size or we
+ * are explicitly asked to change it. This handles the
+ * semantic difference between truncate() and ftruncate() as
+ * implemented in the VFS.
+ *
+ * The regular truncate() case without ATTR_CTIME and
+ * ATTR_MTIME is a special case where we need to update the
+ * times despite not having these flags set. For all other
+ * operations the VFS set these flags explicitly if it wants
+ * a timestamp update.
+ */
+ if (attr->ia_size != i_size_read(inode) &&
+ !(attr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {
+ attr->ia_ctime = attr->ia_mtime =
+ current_fs_time(inode->i_sb);
+ attr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
+ }
}
/* Optimization: if the end result is no change, don't RPC */
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
