Re: Subject: [PATCH 01/16] Squashfs: inode operations

From: JÃrn Engel
Date: Fri Oct 17 2008 - 12:53:31 EST


None of the comments below are a reason against mainline inclusion, imo.
They should get handled, but whether that happens before or after a
merge doesn't really matter.

On Fri, 17 October 2008 16:42:50 +0100, Phillip Lougher wrote:
>
> +#include <linux/squashfs_fs.h>
> +#include <linux/squashfs_fs_sb.h>
> +#include <linux/squashfs_fs_i.h>

Current verdict seems to be that these files should live in fs/squashfs/,
not include/linux/. No kernel code beside squashfs needs the headers
and userspace tools should have a private copy.

> +static int squashfs_new_inode(struct super_block *s, struct inode *i,
> + struct squashfs_base_inode *inodeb)
> +{
> + if (squashfs_get_id(s, le16_to_cpu(inodeb->uid), &i->i_uid) == 0)
> + goto out;
> + if (squashfs_get_id(s, le16_to_cpu(inodeb->guid), &i->i_gid) == 0)
> + goto out;
> +
> + i->i_ino = le32_to_cpu(inodeb->inode_number);
> + i->i_mtime.tv_sec = le32_to_cpu(inodeb->mtime);
> + i->i_atime.tv_sec = i->i_mtime.tv_sec;
> + i->i_ctime.tv_sec = i->i_mtime.tv_sec;
> + i->i_mode = le16_to_cpu(inodeb->mode);
> + i->i_size = 0;
> +
> + return 1;
> +
> +out:
> + return 0;
> +}

Most code uses "sb" and "inode", which I consider easier to read - if
only for consistency.

> +int squashfs_read_inode(struct inode *i, long long inode)

Is your "long long inode" what most filesystems call "inode->i_ino"? It
seems to be.

> + if (squashfs_new_inode(s, i, inodeb) == 0)
> + goto failed_read;

Most linux functions return 0 on success and -ESOMETHING on error. You
return 0 on error and 1 on success. That makes it likely for someone
else to do something like

err = squashfs_foo(bar);
if (err)
goto fail;

Oops.

JÃrn

--
Measure. Don't tune for speed until you've measured, and even then
don't unless one part of the code overwhelms the rest.
-- Rob Pike
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