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Date:   Mon, 21 Mar 2022 17:14:38 -0700
From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH] f2fs: introduce data read/write showing path
 info
Message-ID: <YjkU7tP+Rjs90X38@google.com>
References: <20220321223315.3228326-1-jaegeuk@kernel.org>
 <Yjj/L5/kwc5Oo74E@gmail.com>
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On 03/21, Eric Biggers wrote:
> On Mon, Mar 21, 2022 at 03:33:15PM -0700, Jaegeuk Kim wrote:
> > This was used in Android for a long time. Let's upstream it.
> > 
> 
> You still need to explain why this is useful.
> 
> > +static inline char *f2fs_get_pathname(char *buf, int len, struct inode *inode)
> > +{
> > +	char *path;
> > +	struct dentry *d;
> > +
> > +	/*
> > +	 * d_obtain_alias() will either iput() if it locates an existing
> > +	 * dentry or transfer the reference to the new dentry created.
> > +	 * So get an extra reference here.
> > +	 */
> > +	ihold(inode);
> > +	d = d_obtain_alias(inode);
> 
> Why does this use d_obtain_alias() to get a dentry instead of just using the
> dentry of the open file?

:( I shouldn't copy the code from aosp simply.

> 
> - Eric