RE: [PATCH v9 01/13] exfat: add in-memory and on-disk structures and headers

["Namjae Jeon" <namjae.jeon@samsung.com>]

> On Thu, Jan 02, 2020 at 04:20:24PM +0800, Namjae Jeon wrote:
> > This adds in-memory and on-disk structures and headers.
> >
> > Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
> > Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
> 
> This looks good modulo a few cosmetic nitpicks below.
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
Thanks!

> 
> > --- /dev/null
> > +++ b/fs/exfat/exfat_fs.h
> > @@ -0,0 +1,569 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/*
> > + * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
> > + */
> > +
> > +#ifndef _EXFAT_H
> > +#define _EXFAT_H
> 
> This should probably be _EXFAT_FS_H to match the actual file name.
Right, Will fix it on v10.
> 
> > +
> > +#include <linux/fs.h>
> > +#include <linux/ratelimit.h>
> > +
> > +#define EXFAT_SUPER_MAGIC       (0x2011BAB0UL)
> 
> No need for the braces.
Yes.

> 
> > +/*
> > + * exfat common MACRO
> > + */
> 
> Not sure this comment is all that helpful.
Will remove it.

> 
> > +#define CLUSTER_32(x)			((unsigned int)((x) &
0xFFFFFFFFU))
> 
> This could just use lower_32_bits().
Okay.
> 
> > +#define EXFAT_BAD_CLUSTER		(0xFFFFFFF7U)
> > +#define EXFAT_FREE_CLUSTER		(0)
> > +/* Cluster 0, 1 are reserved, the first cluster is 2 in the cluster
> heap. */
> > +#define EXFAT_RESERVED_CLUSTERS		(2)
> > +#define EXFAT_FIRST_CLUSTER		(2)
> 
> No need for the braces.
Okay.
> 
> > +/* type values */
> > +#define TYPE_UNUSED		0x0000
> > +#define TYPE_DELETED		0x0001
> > +#define TYPE_INVALID		0x0002
> > +#define TYPE_CRITICAL_PRI	0x0100
> > +#define TYPE_BITMAP		0x0101
> > +#define TYPE_UPCASE		0x0102
> > +#define TYPE_VOLUME		0x0103
> > +#define TYPE_DIR		0x0104
> > +#define TYPE_FILE		0x011F
> > +#define TYPE_CRITICAL_SEC	0x0200
> > +#define TYPE_STREAM		0x0201
> > +#define TYPE_EXTEND		0x0202
> > +#define TYPE_ACL		0x0203
> > +#define TYPE_BENIGN_PRI		0x0400
> > +#define TYPE_GUID		0x0401
> > +#define TYPE_PADDING		0x0402
> > +#define TYPE_ACLTAB		0x0403
> > +#define TYPE_BENIGN_SEC		0x0800
> > +#define TYPE_ALL		0x0FFF
> 
> Shouldn't this go into exfat_raw.h?
Yes, These are not.

> Maybe check if a few other values should as well if they define an on-disk
format.
Right, I found a few values which should be move to exfat_raw.h.
Will fix.

> 
> > +static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info
> *sbi,
> > +		unsigned int clus)
> > +{
> > +	return ((clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits)
> > +		+ sbi->data_start_sector;
> 
> Nitpick: normally we put the operators at the of the previous line in
> Linux code.
Okay.
> 
> > +#define EXFAT_DELETE		~(0x80)
> 
> The braces would more useful outside the ~.
Okay.
> 
> > +#define file_num_ext			dentry.file.num_ext
> > +#define file_checksum			dentry.file.checksum
> > +#define file_attr			dentry.file.attr
> > +#define file_create_time		dentry.file.create_time
> > +#define file_create_date		dentry.file.create_date
> > +#define file_modify_time		dentry.file.modify_time
> > +#define file_modify_date		dentry.file.modify_date
> > +#define file_access_time		dentry.file.access_time
> > +#define file_access_date		dentry.file.access_date
> > +#define file_create_time_ms		dentry.file.create_time_ms
> > +#define file_modify_time_ms		dentry.file.modify_time_ms
> > +#define file_create_tz			dentry.file.create_tz
> > +#define file_modify_tz			dentry.file.modify_tz
> > +#define file_access_tz			dentry.file.access_tz
> > +#define stream_flags			dentry.stream.flags
> > +#define stream_name_len			dentry.stream.name_len
> > +#define stream_name_hash		dentry.stream.name_hash
> > +#define stream_start_clu		dentry.stream.start_clu
> > +#define stream_valid_size		dentry.stream.valid_size
> > +#define stream_size			dentry.stream.size
> > +#define name_flags			dentry.name.flags
> > +#define name_unicode			dentry.name.unicode_0_14
> > +#define bitmap_flags			dentry.bitmap.flags
> > +#define bitmap_start_clu		dentry.bitmap.start_clu
> > +#define bitmap_size			dentry.bitmap.size
> > +#define upcase_start_clu		dentry.upcase.start_clu
> > +#define upcase_size			dentry.upcase.size
> > +#define upcase_checksum			dentry.upcase.checksum
> 
> Personally I don't find these defines very helpful - directly seeing the
> field name makes the code much easier to read.
Okay, Will remove them.

Thanks for your review!