RE: [PATCH] f2fs: introduce F2FS_MAX_BLOCKS

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx]
> Sent: Wednesday, December 30, 2015 9:14 AM
> To: Chao Yu
> Cc: linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] f2fs: introduce F2FS_MAX_BLOCKS
> 
> Hi Chao,
> 
> On Tue, Dec 29, 2015 at 05:48:04PM +0800, Chao Yu wrote:
> > Introduce a macro named F2FS_MAX_BLOCKS to indicate maximum block index
> > in f2fs, it could be used to avoid unneeded calculation in runtime.
> 
> It's not so different from previous one.

Yes, just save some time of calculation in max_file_size if it is
used in bmap frequently.

> 
> How about adding something like:
> 
> static loff_t max_file_size(unsigned bits)

@bits will no longer be used, how about remove this parameter?

> {
> }
> 
> ...
> 
> sbi->max_file_blocks = max_file_size(0);

If max_file_size return max block index of file, how about rename it to
max_file_blocks() for readability?

Thanks,

> sb->max_file_size =
> 	sbi->max_file_blocks << le32_to_cpu(raw_super->log_blocksize);
> 
> ...
> 
> Thanks,
> 
> >
> > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx>
> > ---
> >  fs/f2fs/data.c          |  2 +-
> >  fs/f2fs/f2fs.h          |  1 -
> >  fs/f2fs/super.c         | 19 ++-----------------
> >  include/linux/f2fs_fs.h |  5 +++++
> >  4 files changed, 8 insertions(+), 19 deletions(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index 7175d33..a366a4c 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -762,7 +762,7 @@ static int get_data_block_bmap(struct inode *inode, sector_t iblock,
> >  			struct buffer_head *bh_result, int create)
> >  {
> >  	/* Block number less than F2FS MAX BLOCKS */
> > -	if (unlikely(iblock > max_file_size(0)))
> > +	if (unlikely(iblock > F2FS_MAX_BLOCKS))
> >  		return -EFBIG;
> >
> >  	return __get_data_block(inode, iblock, bh_result, create,
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 9ba6a09..95c6f38 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -1731,7 +1731,6 @@ static inline int f2fs_add_link(struct dentry *dentry, struct inode
> *inode)
> >   * super.c
> >   */
> >  int f2fs_commit_super(struct f2fs_sb_info *, bool);
> > -loff_t max_file_size(unsigned bits);
> >  int f2fs_sync_fs(struct super_block *, int);
> >  extern __printf(3, 4)
> >  void f2fs_msg(struct super_block *, const char *, const char *, ...);
> > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > index f474355..5f7e632 100644
> > --- a/fs/f2fs/super.c
> > +++ b/fs/f2fs/super.c
> > @@ -909,24 +909,9 @@ static const struct export_operations f2fs_export_ops = {
> >  	.get_parent = f2fs_get_parent,
> >  };
> >
> > -loff_t max_file_size(unsigned bits)
> > +static loff_t max_file_size(unsigned bits)
> >  {
> > -	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
> > -	loff_t leaf_count = ADDRS_PER_BLOCK;
> > -
> > -	/* two direct node blocks */
> > -	result += (leaf_count * 2);
> > -
> > -	/* two indirect node blocks */
> > -	leaf_count *= NIDS_PER_BLOCK;
> > -	result += (leaf_count * 2);
> > -
> > -	/* one double indirect node block */
> > -	leaf_count *= NIDS_PER_BLOCK;
> > -	result += leaf_count;
> > -
> > -	result <<= bits;
> > -	return result;
> > +	return ((loff_t)F2FS_MAX_BLOCKS << bits);
> >  }
> >
> >  static inline bool sanity_check_area_boundary(struct super_block *sb,
> > diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
> > index e59c3be..814c471 100644
> > --- a/include/linux/f2fs_fs.h
> > +++ b/include/linux/f2fs_fs.h
> > @@ -189,6 +189,11 @@ struct f2fs_extent {
> >  #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
> >  #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
> >
> > +#define F2FS_MAX_BLOCKS		((DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS) + \
> > +				ADDRS_PER_BLOCK * 2 + ADDRS_PER_BLOCK * \
> > +				NIDS_PER_BLOCK * 2 + ADDRS_PER_BLOCK * \
> > +				NIDS_PER_BLOCK * NIDS_PER_BLOCK)
> > +
> >  #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
> >  						F2FS_INLINE_XATTR_ADDRS - 1))
> >
> > --
> > 2.6.3
> >

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/