linux-kernel - Re: [PATCH 12/19] pramfs: symlink operations

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Date:	Sat, 07 Sep 2013 18:09:27 +0200
From:	Marco Stornelli <marco.stornelli@...il.com>
To:	Al Viro <viro@...IV.linux.org.uk>
CC:	Vladimir Davydov <vdavydov@...allels.com>,
	linux-kernel@...r.kernel.org,
	Linux FS Devel <linux-fsdevel@...r.kernel.org>
Subject: Re: [PATCH 12/19] pramfs: symlink operations

Il 07/09/2013 16:41, Al Viro ha scritto:
> On Sat, Sep 07, 2013 at 10:29:15AM +0200, Marco Stornelli wrote:
>> +static int pram_readlink(struct dentry *dentry, char __user *buffer, int buflen)
>> +{
>> +	struct inode *inode = dentry->d_inode;
>> +	struct super_block *sb = inode->i_sb;
>> +	u64 block;
>> +	char *blockp;
>> +
>> +	block = pram_find_data_block(inode, 0);
>> +	blockp = pram_get_block(sb, block);
>> +	return vfs_readlink(dentry, buffer, buflen, blockp);
>> +}
>
>> +static void *pram_follow_link(struct dentry *dentry, struct nameidata *nd)
>> +{
>> +	struct inode *inode = dentry->d_inode;
>> +	struct super_block *sb = inode->i_sb;
>> +	off_t block;
>> +	int status;
>> +	char *blockp;
>> +
>> +	block = pram_find_data_block(inode, 0);
>> +	blockp = pram_get_block(sb, block);
>> +	status = vfs_follow_link(nd, blockp);
>> +	return ERR_PTR(status);
>> +}
>
> Just nd_set_link(nd, blockp) instead of that vfs_follow_link() and be
> done with that; that way you can use generic_readlink() instead of
> pram_readlink() *and* get lower stack footprint on traversing them.
>
>

Yep, you're right (as usual :))

Marco

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