<div dir="auto"><div><br><div class="gmail_extra"><br><div class="gmail_quote">On 16-Jun-2017 11:44 AM, "Shrikant Giridhar" <<a href="mailto:shrikantgiridhar@gmail.com">shrikantgiridhar@gmail.com</a>> wrote:<br type="attribution"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="quoted-text">> I just had a quick look at mount_bdev() code for Linux v3.15, mount_bdev()<br>
> can return only root dentry or error.<br>
<br>
</div>I'm sorry I should have been clearer. I was referring to the documentation<br>
mount() where it says that the call can return something other than the root<br>
dentry.<br></blockquote></div></div></div><div dir="auto">I have not looked at the doc.</div><div dir="auto"><div class="gmail_extra"><div class="gmail_quote"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
More specifically, I don't understand how the what's the purpose of the if<br>
condition checking for s_root in mount_bdev(). Apologies if this is a trivial<br>
question.</blockquote></div></div></div><div dir="auto">If s_root is set it means the superblock is already filled up so call fill_super() only if s_root is NULL meaning superblock is not filled yet.</div><div dir="auto"><div class="gmail_extra"><div class="gmail_quote"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Tracking the calls all the way down didn't seem to make it clearer<br>
and I couldn't find specific documentation about the interface.<br>
<div class="quoted-text"><br>
> Also please include the kernel version to which you are referring.<br>
<br>
</div>I have the 4.12-rc5 kernel.<br>
<br>
---<br>
Shrikant<br>
</blockquote></div><br></div><div class="gmail_extra" dir="auto">- Rohan</div></div></div>