[tytso-ext4:dev 40/41] fs/ext4/inode.c:4518 ext4_iomap_writepages() warn: missing error code? 'ret'

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

Unfiltered warning: this smatch report is sent as-is and has not been
reviewed for false positives, so please treat it with due skepticism.

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-ext4@vger.kernel.org
TO: Zhang Yi <yi.zhang@huawei.com>
CC: "Theodore Ts'o" <tytso@mit.edu>

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git dev
head:   8c4f6e3376348fc3162eed86a05b933921c8f9ed
commit: bdcbb0f19e921c7ea3241f55922032dff23d1d26 [40/41] ext4: partially enable iomap for the buffered I/O path of regular files
:::::: branch date: 11 hours ago
:::::: commit date: 11 hours ago
config: x86_64-randconfig-2200-20261016 (https://download.01.org/0day-ci/archive/20261016/202610160314.PLMEXaOJ-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
smatch: v0.5.0-9187-g5189e3fb

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202610160314.PLMEXaOJ-lkp@intel.com/

New smatch warnings:
fs/ext4/inode.c:4518 ext4_iomap_writepages() warn: missing error code? 'ret'

Old smatch warnings:
fs/ext4/inode.c:2785 mpage_prepare_extent_to_map() warn: missing error code 'err'
fs/ext4/inode.c:6085 check_igot_inode() warn: missing unwind goto?

vim +/ret +4518 fs/ext4/inode.c

53fe71a6bcad0f Zhang Yi 2026-10-09  4487  
a304299a40d92c Zhang Yi 2026-10-09  4488  static int ext4_iomap_writepages(struct address_space *mapping,
a304299a40d92c Zhang Yi 2026-10-09  4489  				 struct writeback_control *wbc)
a304299a40d92c Zhang Yi 2026-10-09  4490  {
a2e096bf59634f Zhang Yi 2026-10-09  4491  	struct inode *inode = mapping->host;
a2e096bf59634f Zhang Yi 2026-10-09  4492  	struct super_block *sb = inode->i_sb;
a2e096bf59634f Zhang Yi 2026-10-09  4493  	long nr = wbc->nr_to_write;
a2e096bf59634f Zhang Yi 2026-10-09  4494  	int alloc_ctx, ret;
a2e096bf59634f Zhang Yi 2026-10-09  4495  	struct iomap_writepage_ctx wpc = {
a2e096bf59634f Zhang Yi 2026-10-09  4496  		.inode = inode,
a2e096bf59634f Zhang Yi 2026-10-09  4497  		.wbc = wbc,
a2e096bf59634f Zhang Yi 2026-10-09  4498  		.ops = &ext4_writeback_ops,
a2e096bf59634f Zhang Yi 2026-10-09  4499  	};
a2e096bf59634f Zhang Yi 2026-10-09  4500  
a2e096bf59634f Zhang Yi 2026-10-09  4501  	ret = ext4_emergency_state(sb);
a2e096bf59634f Zhang Yi 2026-10-09  4502  	if (unlikely(ret))
a2e096bf59634f Zhang Yi 2026-10-09  4503  		return ret;
a2e096bf59634f Zhang Yi 2026-10-09  4504  
53fe71a6bcad0f Zhang Yi 2026-10-09  4505  	/*
53fe71a6bcad0f Zhang Yi 2026-10-09  4506  	 * Submit the pending zeroed EOF block range if the entire
53fe71a6bcad0f Zhang Yi 2026-10-09  4507  	 * writeback range lies beyond it.
53fe71a6bcad0f Zhang Yi 2026-10-09  4508  	 */
53fe71a6bcad0f Zhang Yi 2026-10-09  4509  	ext4_iomap_wb_submit_zeroed_eof(inode, wbc);
53fe71a6bcad0f Zhang Yi 2026-10-09  4510  
a2e096bf59634f Zhang Yi 2026-10-09  4511  	alloc_ctx = ext4_writepages_down_read(sb);
bdcbb0f19e921c Zhang Yi 2026-10-09  4512  	/*
bdcbb0f19e921c Zhang Yi 2026-10-09  4513  	 * Does ext4_change_inode_journal_flag() change the inode's
bdcbb0f19e921c Zhang Yi 2026-10-09  4514  	 * buffered I/O path?
bdcbb0f19e921c Zhang Yi 2026-10-09  4515  	 */
bdcbb0f19e921c Zhang Yi 2026-10-09  4516  	if (!ext4_inode_buffered_iomap(inode)) {
bdcbb0f19e921c Zhang Yi 2026-10-09  4517  		ext4_writepages_up_read(sb, alloc_ctx);
bdcbb0f19e921c Zhang Yi 2026-10-09 @4518  		return ret;
bdcbb0f19e921c Zhang Yi 2026-10-09  4519  	}
bdcbb0f19e921c Zhang Yi 2026-10-09  4520  
a2e096bf59634f Zhang Yi 2026-10-09  4521  	trace_ext4_writepages(inode, wbc);
a2e096bf59634f Zhang Yi 2026-10-09  4522  	ret = iomap_writepages(&wpc);
a2e096bf59634f Zhang Yi 2026-10-09  4523  	trace_ext4_writepages_result(inode, wbc, ret, nr - wbc->nr_to_write);
a2e096bf59634f Zhang Yi 2026-10-09  4524  	ext4_writepages_up_read(sb, alloc_ctx);
a2e096bf59634f Zhang Yi 2026-10-09  4525  
a2e096bf59634f Zhang Yi 2026-10-09  4526  	return ret;
a304299a40d92c Zhang Yi 2026-10-09  4527  }
a304299a40d92c Zhang Yi 2026-10-09  4528  

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