Re: [PATCH] ext4: defer updating i_disksize until endio

[kernel test robot <lkp@intel.com>]

Hi Chung-Chiang,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on v6.3-rc3]
[also build test WARNING on linus/master]
[cannot apply to tytso-ext4/dev next-20230324]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Chung-Chiang-Cheng/ext4-defer-updating-i_disksize-until-endio/20230324-173716
patch link:    https://lore.kernel.org/r/20230324092907.1341457-1-cccheng%40synology.com
patch subject: [PATCH] ext4: defer updating i_disksize until endio
config: ia64-allyesconfig (https://download.01.org/0day-ci/archive/20230324/202303242033.wiXS9jKn-lkp@intel.com/config)
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/9a02b364d2cffe71a45866edf750b0280c8cb990
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Chung-Chiang-Cheng/ext4-defer-updating-i_disksize-until-endio/20230324-173716
        git checkout 9a02b364d2cffe71a45866edf750b0280c8cb990
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash fs/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303242033.wiXS9jKn-lkp@intel.com/

All warnings (new ones prefixed by >>):

   fs/ext4/inode.c: In function 'ext4_da_write_end':
>> fs/ext4/inode.c:3115:30: warning: variable 'end' set but not used [-Wunused-but-set-variable]
    3115 |         unsigned long start, end;
         |                              ^~~


vim +/end +3115 fs/ext4/inode.c

64769240bd07f4 Alex Tomas         2008-07-11  3108  
64769240bd07f4 Alex Tomas         2008-07-11  3109  static int ext4_da_write_end(struct file *file,
64769240bd07f4 Alex Tomas         2008-07-11  3110  			     struct address_space *mapping,
64769240bd07f4 Alex Tomas         2008-07-11  3111  			     loff_t pos, unsigned len, unsigned copied,
64769240bd07f4 Alex Tomas         2008-07-11  3112  			     struct page *page, void *fsdata)
64769240bd07f4 Alex Tomas         2008-07-11  3113  {
64769240bd07f4 Alex Tomas         2008-07-11  3114  	struct inode *inode = mapping->host;
632eaeab1feb5d Mingming Cao       2008-07-11 @3115  	unsigned long start, end;
79f0be8d2e6ebd Aneesh Kumar K.V   2008-10-08  3116  	int write_mode = (int)(unsigned long)fsdata;
79f0be8d2e6ebd Aneesh Kumar K.V   2008-10-08  3117  
74d553aad7926e Theodore Ts'o      2013-04-03  3118  	if (write_mode == FALL_BACK_TO_NONDELALLOC)
74d553aad7926e Theodore Ts'o      2013-04-03  3119  		return ext4_write_end(file, mapping, pos,
79f0be8d2e6ebd Aneesh Kumar K.V   2008-10-08  3120  				      len, copied, page, fsdata);
632eaeab1feb5d Mingming Cao       2008-07-11  3121  
9bffad1ed2a003 Theodore Ts'o      2009-06-17  3122  	trace_ext4_da_write_end(inode, pos, len, copied);
6984aef59814fb Zhang Yi           2021-07-16  3123  
6984aef59814fb Zhang Yi           2021-07-16  3124  	if (write_mode != CONVERT_INLINE_DATA &&
6984aef59814fb Zhang Yi           2021-07-16  3125  	    ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) &&
6984aef59814fb Zhang Yi           2021-07-16  3126  	    ext4_has_inline_data(inode))
6984aef59814fb Zhang Yi           2021-07-16  3127  		return ext4_write_inline_data_end(inode, pos, len, copied, page);
6984aef59814fb Zhang Yi           2021-07-16  3128  
09cbfeaf1a5a67 Kirill A. Shutemov 2016-04-01  3129  	start = pos & (PAGE_SIZE - 1);
632eaeab1feb5d Mingming Cao       2008-07-11  3130  	end = start + copied - 1;
64769240bd07f4 Alex Tomas         2008-07-11  3131  
64769240bd07f4 Alex Tomas         2008-07-11  3132  	/*
4df031ff5876d9 Zhang Yi           2021-07-16  3133  	 * Since we are holding inode lock, we are sure i_disksize <=
4df031ff5876d9 Zhang Yi           2021-07-16  3134  	 * i_size. We also know that if i_disksize < i_size, there are
9a02b364d2cffe Chung-Chiang Cheng 2023-03-24  3135  	 * delalloc writes pending in the range upto i_size. There's no
9a02b364d2cffe Chung-Chiang Cheng 2023-03-24  3136  	 * need to touch i_disksize since the endio of writeback will
9a02b364d2cffe Chung-Chiang Cheng 2023-03-24  3137  	 * push i_disksize upto i_size eventually.
4df031ff5876d9 Zhang Yi           2021-07-16  3138  	 *
4df031ff5876d9 Zhang Yi           2021-07-16  3139  	 * Note that we defer inode dirtying to generic_write_end() /
4df031ff5876d9 Zhang Yi           2021-07-16  3140  	 * ext4_da_write_inline_data_end().
64769240bd07f4 Alex Tomas         2008-07-11  3141  	 */
9c3569b50f12e4 Tao Ma             2012-12-10  3142  
cc883236b79297 Zhang Yi           2021-07-16  3143  	return generic_write_end(file, mapping, pos, len, copied, page, fsdata);
64769240bd07f4 Alex Tomas         2008-07-11  3144  }
64769240bd07f4 Alex Tomas         2008-07-11  3145  

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