Re: [PATCH 6/6] ext4: convert to new fserror helpers

["Darrick J. Wong" <djwong@kernel.org>]

On Mon, Dec 22, 2025 at 04:34:48PM +0100, Jan Kara wrote:
> On Wed 17-12-25 18:04:14, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > Use the new fserror functions to report metadata errors to fsnotify.
> > Note that ext4 inconsistently passes around negative and positive error
> > numbers all over the codebase, so we force them all to negative for
> > consistency in what we report to fserror, and fserror ensures that only
> > positive error numbers are passed to fanotify, per the fanotify(7)
> > manpage.
> > 
> > Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
> 
> We need to cleanup those error numbers passing - we should have mostly
> negative ones AFAIK - where do we end up passing positive ones? But it's
> unrelated to this patch so feel free to add:

Here and there:

$ git grep 'ext4_error.*[[:space:]]E[A-Z]' fs/ext4/
fs/ext4/balloc.c:582:           ext4_error_err(sb, EIO, "Cannot read block bitmap - "
fs/ext4/ialloc.c:201:           ext4_error_err(sb, EIO, "Cannot read inode bitmap - "
fs/ext4/inode.c:4952:           ext4_error_inode_block(inode, err_blk, EIO,
fs/ext4/inode.c:4967:           ext4_error_inode_block(inode, err_blk, EIO,
fs/ext4/inode.c:5188:           __ext4_error(sb, function, line, false, EFSCORRUPTED, 0,
fs/ext4/inode.c:5728:                   ext4_error_inode_block(inode, iloc.bh->b_blocknr, EIO,
fs/ext4/mmp.c:218:                              ext4_error_err(sb, EBUSY, "abort");

> Reviewed-by: Jan Kara <jack@suse.cz>

Thanks!

--D

> 
> 								Honza
> 
> > ---
> >  fs/ext4/ioctl.c |    2 ++
> >  fs/ext4/super.c |   13 +++++++++----
> >  2 files changed, 11 insertions(+), 4 deletions(-)
> > 
> > 
> > diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
> > index 7ce0fc40aec2fb..ea26cd03d3ce28 100644
> > --- a/fs/ext4/ioctl.c
> > +++ b/fs/ext4/ioctl.c
> > @@ -26,6 +26,7 @@
> >  #include <linux/fsmap.h>
> >  #include "fsmap.h"
> >  #include <trace/events/ext4.h>
> > +#include <linux/fserror.h>
> >  
> >  typedef void ext4_update_sb_callback(struct ext4_sb_info *sbi,
> >  				     struct ext4_super_block *es,
> > @@ -844,6 +845,7 @@ int ext4_force_shutdown(struct super_block *sb, u32 flags)
> >  		return -EINVAL;
> >  	}
> >  	clear_opt(sb, DISCARD);
> > +	fserror_report_shutdown(sb, GFP_KERNEL);
> >  	return 0;
> >  }
> >  
> > diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> > index 87205660c5d026..a6241ffb8639c3 100644
> > --- a/fs/ext4/super.c
> > +++ b/fs/ext4/super.c
> > @@ -48,6 +48,7 @@
> >  #include <linux/fsnotify.h>
> >  #include <linux/fs_context.h>
> >  #include <linux/fs_parser.h>
> > +#include <linux/fserror.h>
> >  
> >  #include "ext4.h"
> >  #include "ext4_extents.h"	/* Needed for trace points definition */
> > @@ -824,7 +825,8 @@ void __ext4_error(struct super_block *sb, const char *function,
> >  		       sb->s_id, function, line, current->comm, &vaf);
> >  		va_end(args);
> >  	}
> > -	fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
> > +	fserror_report_metadata(sb, error ? -abs(error) : -EFSCORRUPTED,
> > +				GFP_ATOMIC);
> >  
> >  	ext4_handle_error(sb, force_ro, error, 0, block, function, line);
> >  }
> > @@ -856,7 +858,9 @@ void __ext4_error_inode(struct inode *inode, const char *function,
> >  			       current->comm, &vaf);
> >  		va_end(args);
> >  	}
> > -	fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
> > +	fserror_report_file_metadata(inode,
> > +				     error ? -abs(error) : -EFSCORRUPTED,
> > +				     GFP_ATOMIC);
> >  
> >  	ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
> >  			  function, line);
> > @@ -896,7 +900,7 @@ void __ext4_error_file(struct file *file, const char *function,
> >  			       current->comm, path, &vaf);
> >  		va_end(args);
> >  	}
> > -	fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
> > +	fserror_report_file_metadata(inode, -EFSCORRUPTED, GFP_ATOMIC);
> >  
> >  	ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
> >  			  function, line);
> > @@ -965,7 +969,8 @@ void __ext4_std_error(struct super_block *sb, const char *function,
> >  		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
> >  		       sb->s_id, function, line, errstr);
> >  	}
> > -	fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
> > +	fserror_report_metadata(sb, errno ? -abs(errno) : -EFSCORRUPTED,
> > +				GFP_ATOMIC);
> >  
> >  	ext4_handle_error(sb, false, -errno, 0, 0, function, line);
> >  }
> > 
> -- 
> Jan Kara <jack@suse.com>
> SUSE Labs, CR
>