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

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

[Darrick J. Wong]

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>
---
 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);
 }

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

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

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

[Jan Kara]

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:

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

								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

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

[Darrick J. Wong]

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
> 

[PATCHSET v5] fs: generic file IO error reporting

[Darrick J. Wong]

Hi all,

This patchset adds some generic helpers so that filesystems can report
errors to fsnotify in a standard way.  Then it adapts iomap to use the
generic helpers so that any iomap-enabled filesystem can report I/O
errors through this mechanism as well.  Finally, it makes XFS report
metadata errors through this mechanism in much the same way that ext4
does now.

These are a prerequisite for the XFS self-healing series which will
come at a later time.

v5: tidy comments, un-inline the unmount function
v4: drag out of RFC status, finalize the sign of errnos that we accept

If you're going to start using this code, I strongly recommend pulling
from my git trees, which are linked below.

This has been running on the djcloud for months with no problems.  Enjoy!
Comments and questions are, as always, welcome.

--D

kernel git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=filesystem-error-reporting

fstests git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfstests-dev.git/log/?h=filesystem-error-reporting
---
Commits in this patchset:
 * uapi: promote EFSCORRUPTED and EUCLEAN to errno.h
 * fs: report filesystem and file I/O errors to fsnotify
 * iomap: report file I/O errors to the VFS
 * xfs: report fs metadata errors via fsnotify
 * xfs: translate fsdax media errors into file "data lost" errors when convenient
 * ext4: convert to new fserror helpers
---
 arch/alpha/include/uapi/asm/errno.h        |    2 
 arch/mips/include/uapi/asm/errno.h         |    2 
 arch/parisc/include/uapi/asm/errno.h       |    2 
 arch/sparc/include/uapi/asm/errno.h        |    2 
 fs/erofs/internal.h                        |    2 
 fs/ext2/ext2.h                             |    1 
 fs/ext4/ext4.h                             |    3 
 fs/f2fs/f2fs.h                             |    3 
 fs/minix/minix.h                           |    2 
 fs/udf/udf_sb.h                            |    2 
 fs/xfs/xfs_linux.h                         |    2 
 include/linux/fs/super_types.h             |    7 +
 include/linux/fserror.h                    |   75 +++++++++++
 include/linux/jbd2.h                       |    3 
 include/uapi/asm-generic/errno.h           |    2 
 tools/arch/alpha/include/uapi/asm/errno.h  |    2 
 tools/arch/mips/include/uapi/asm/errno.h   |    2 
 tools/arch/parisc/include/uapi/asm/errno.h |    2 
 tools/arch/sparc/include/uapi/asm/errno.h  |    2 
 tools/include/uapi/asm-generic/errno.h     |    2 
 fs/Makefile                                |    2 
 fs/ext4/ioctl.c                            |    2 
 fs/ext4/super.c                            |   13 +-
 fs/fserror.c                               |  194 ++++++++++++++++++++++++++++
 fs/iomap/buffered-io.c                     |   23 +++
 fs/iomap/direct-io.c                       |   12 ++
 fs/iomap/ioend.c                           |    6 +
 fs/super.c                                 |    3 
 fs/xfs/xfs_fsops.c                         |    4 +
 fs/xfs/xfs_health.c                        |   14 ++
 fs/xfs/xfs_notify_failure.c                |    4 +
 31 files changed, 373 insertions(+), 24 deletions(-)
 create mode 100644 include/linux/fserror.h
 create mode 100644 fs/fserror.c

[PATCH 1/6] uapi: promote EFSCORRUPTED and EUCLEAN to errno.h

[Darrick J. Wong]

From: Darrick J. Wong <djwong@kernel.org>

Stop definining these privately and instead move them to the uapi
errno.h so that they become canonical instead of copy pasta.

Cc: linux-api@vger.kernel.org
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 arch/alpha/include/uapi/asm/errno.h        |    2 ++
 arch/mips/include/uapi/asm/errno.h         |    2 ++
 arch/parisc/include/uapi/asm/errno.h       |    2 ++
 arch/sparc/include/uapi/asm/errno.h        |    2 ++
 fs/erofs/internal.h                        |    2 --
 fs/ext2/ext2.h                             |    1 -
 fs/ext4/ext4.h                             |    3 ---
 fs/f2fs/f2fs.h                             |    3 ---
 fs/minix/minix.h                           |    2 --
 fs/udf/udf_sb.h                            |    2 --
 fs/xfs/xfs_linux.h                         |    2 --
 include/linux/jbd2.h                       |    3 ---
 include/uapi/asm-generic/errno.h           |    2 ++
 tools/arch/alpha/include/uapi/asm/errno.h  |    2 ++
 tools/arch/mips/include/uapi/asm/errno.h   |    2 ++
 tools/arch/parisc/include/uapi/asm/errno.h |    2 ++
 tools/arch/sparc/include/uapi/asm/errno.h  |    2 ++
 tools/include/uapi/asm-generic/errno.h     |    2 ++
 18 files changed, 20 insertions(+), 18 deletions(-)


diff --git a/arch/alpha/include/uapi/asm/errno.h b/arch/alpha/include/uapi/asm/errno.h
index 3d265f6babaf0a..6791f6508632ee 100644
--- a/arch/alpha/include/uapi/asm/errno.h
+++ b/arch/alpha/include/uapi/asm/errno.h
@@ -55,6 +55,7 @@
 #define	ENOSR		82	/* Out of streams resources */
 #define	ETIME		83	/* Timer expired */
 #define	EBADMSG		84	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EPROTO		85	/* Protocol error */
 #define	ENODATA		86	/* No data available */
 #define	ENOSTR		87	/* Device not a stream */
@@ -96,6 +97,7 @@
 #define	EREMCHG		115	/* Remote address changed */
 
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */
diff --git a/arch/mips/include/uapi/asm/errno.h b/arch/mips/include/uapi/asm/errno.h
index 2fb714e2d6d8fc..c01ed91b1ef44b 100644
--- a/arch/mips/include/uapi/asm/errno.h
+++ b/arch/mips/include/uapi/asm/errno.h
@@ -50,6 +50,7 @@
 #define EDOTDOT		73	/* RFS specific error */
 #define EMULTIHOP	74	/* Multihop attempted */
 #define EBADMSG		77	/* Not a data message */
+#define EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define ENAMETOOLONG	78	/* File name too long */
 #define EOVERFLOW	79	/* Value too large for defined data type */
 #define ENOTUNIQ	80	/* Name not unique on network */
@@ -88,6 +89,7 @@
 #define EISCONN		133	/* Transport endpoint is already connected */
 #define ENOTCONN	134	/* Transport endpoint is not connected */
 #define EUCLEAN		135	/* Structure needs cleaning */
+#define EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define ENOTNAM		137	/* Not a XENIX named type file */
 #define ENAVAIL		138	/* No XENIX semaphores available */
 #define EISNAM		139	/* Is a named type file */
diff --git a/arch/parisc/include/uapi/asm/errno.h b/arch/parisc/include/uapi/asm/errno.h
index 8d94739d75c67c..8cbc07c1903e4c 100644
--- a/arch/parisc/include/uapi/asm/errno.h
+++ b/arch/parisc/include/uapi/asm/errno.h
@@ -36,6 +36,7 @@
 
 #define	EDOTDOT		66	/* RFS specific error */
 #define	EBADMSG		67	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EUSERS		68	/* Too many users */
 #define	EDQUOT		69	/* Quota exceeded */
 #define	ESTALE		70	/* Stale file handle */
@@ -62,6 +63,7 @@
 #define	ERESTART	175	/* Interrupted system call should be restarted */
 #define	ESTRPIPE	176	/* Streams pipe error */
 #define	EUCLEAN		177	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		178	/* Not a XENIX named type file */
 #define	ENAVAIL		179	/* No XENIX semaphores available */
 #define	EISNAM		180	/* Is a named type file */
diff --git a/arch/sparc/include/uapi/asm/errno.h b/arch/sparc/include/uapi/asm/errno.h
index 81a732b902ee38..4a41e7835fd5b8 100644
--- a/arch/sparc/include/uapi/asm/errno.h
+++ b/arch/sparc/include/uapi/asm/errno.h
@@ -48,6 +48,7 @@
 #define	ENOSR		74	/* Out of streams resources */
 #define	ENOMSG		75	/* No message of desired type */
 #define	EBADMSG		76	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EIDRM		77	/* Identifier removed */
 #define	EDEADLK		78	/* Resource deadlock would occur */
 #define	ENOLCK		79	/* No record locks available */
@@ -91,6 +92,7 @@
 #define	ENOTUNIQ	115	/* Name not unique on network */
 #define	ERESTART	116	/* Interrupted syscall should be restarted */
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index f7f622836198da..d06e99baf5d5ae 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -541,6 +541,4 @@ long erofs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
 long erofs_compat_ioctl(struct file *filp, unsigned int cmd,
 			unsigned long arg);
 
-#define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
-
 #endif	/* __EROFS_INTERNAL_H */
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index cf97b76e9fd3e9..5e0c6c5fcb6cd6 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -357,7 +357,6 @@ struct ext2_inode {
  */
 #define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */
 #define	EXT2_ERROR_FS			0x0002	/* Errors detected */
-#define	EFSCORRUPTED			EUCLEAN	/* Filesystem is corrupted */
 
 /*
  * Mount flags
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 56112f201cace7..62c091b52bacdf 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3938,7 +3938,4 @@ extern int ext4_block_write_begin(handle_t *handle, struct folio *folio,
 				  get_block_t *get_block);
 #endif	/* __KERNEL__ */
 
-#define EFSBADCRC	EBADMSG		/* Bad CRC detected */
-#define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
-
 #endif	/* _EXT4_H */
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 20edbb99b814a7..9f3aa3c7f12613 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -5004,7 +5004,4 @@ static inline void f2fs_invalidate_internal_cache(struct f2fs_sb_info *sbi,
 	f2fs_invalidate_compress_pages_range(sbi, blkaddr, len);
 }
 
-#define EFSBADCRC	EBADMSG		/* Bad CRC detected */
-#define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
-
 #endif /* _LINUX_F2FS_H */
diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index 2bfaf377f2086c..7e1f652f16d311 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -175,6 +175,4 @@ static inline int minix_test_bit(int nr, const void *vaddr)
 	__minix_error_inode((inode), __func__, __LINE__,	\
 			    (fmt), ##__VA_ARGS__)
 
-#define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
-
 #endif /* FS_MINIX_H */
diff --git a/fs/udf/udf_sb.h b/fs/udf/udf_sb.h
index 08ec8756b9487b..8399accc788dea 100644
--- a/fs/udf/udf_sb.h
+++ b/fs/udf/udf_sb.h
@@ -55,8 +55,6 @@
 #define MF_DUPLICATE_MD		0x01
 #define MF_MIRROR_FE_LOADED	0x02
 
-#define EFSCORRUPTED EUCLEAN
-
 struct udf_meta_data {
 	__u32	s_meta_file_loc;
 	__u32	s_mirror_file_loc;
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index 4dd747bdbccab2..55064228c4d574 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -121,8 +121,6 @@ typedef __u32			xfs_nlink_t;
 
 #define ENOATTR		ENODATA		/* Attribute not found */
 #define EWRONGFS	EINVAL		/* Mount with wrong filesystem type */
-#define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
-#define EFSBADCRC	EBADMSG		/* Bad CRC detected */
 
 #define __return_address __builtin_return_address(0)
 
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index f5eaf76198f377..a53a00d36228ce 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1815,7 +1815,4 @@ static inline int jbd2_handle_buffer_credits(handle_t *handle)
 
 #endif	/* __KERNEL__ */
 
-#define EFSBADCRC	EBADMSG		/* Bad CRC detected */
-#define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
-
 #endif	/* _LINUX_JBD2_H */
diff --git a/include/uapi/asm-generic/errno.h b/include/uapi/asm-generic/errno.h
index cf9c51ac49f97e..92e7ae493ee315 100644
--- a/include/uapi/asm-generic/errno.h
+++ b/include/uapi/asm-generic/errno.h
@@ -55,6 +55,7 @@
 #define	EMULTIHOP	72	/* Multihop attempted */
 #define	EDOTDOT		73	/* RFS specific error */
 #define	EBADMSG		74	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EOVERFLOW	75	/* Value too large for defined data type */
 #define	ENOTUNIQ	76	/* Name not unique on network */
 #define	EBADFD		77	/* File descriptor in bad state */
@@ -98,6 +99,7 @@
 #define	EINPROGRESS	115	/* Operation now in progress */
 #define	ESTALE		116	/* Stale file handle */
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */
diff --git a/tools/arch/alpha/include/uapi/asm/errno.h b/tools/arch/alpha/include/uapi/asm/errno.h
index 3d265f6babaf0a..6791f6508632ee 100644
--- a/tools/arch/alpha/include/uapi/asm/errno.h
+++ b/tools/arch/alpha/include/uapi/asm/errno.h
@@ -55,6 +55,7 @@
 #define	ENOSR		82	/* Out of streams resources */
 #define	ETIME		83	/* Timer expired */
 #define	EBADMSG		84	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EPROTO		85	/* Protocol error */
 #define	ENODATA		86	/* No data available */
 #define	ENOSTR		87	/* Device not a stream */
@@ -96,6 +97,7 @@
 #define	EREMCHG		115	/* Remote address changed */
 
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */
diff --git a/tools/arch/mips/include/uapi/asm/errno.h b/tools/arch/mips/include/uapi/asm/errno.h
index 2fb714e2d6d8fc..c01ed91b1ef44b 100644
--- a/tools/arch/mips/include/uapi/asm/errno.h
+++ b/tools/arch/mips/include/uapi/asm/errno.h
@@ -50,6 +50,7 @@
 #define EDOTDOT		73	/* RFS specific error */
 #define EMULTIHOP	74	/* Multihop attempted */
 #define EBADMSG		77	/* Not a data message */
+#define EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define ENAMETOOLONG	78	/* File name too long */
 #define EOVERFLOW	79	/* Value too large for defined data type */
 #define ENOTUNIQ	80	/* Name not unique on network */
@@ -88,6 +89,7 @@
 #define EISCONN		133	/* Transport endpoint is already connected */
 #define ENOTCONN	134	/* Transport endpoint is not connected */
 #define EUCLEAN		135	/* Structure needs cleaning */
+#define EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define ENOTNAM		137	/* Not a XENIX named type file */
 #define ENAVAIL		138	/* No XENIX semaphores available */
 #define EISNAM		139	/* Is a named type file */
diff --git a/tools/arch/parisc/include/uapi/asm/errno.h b/tools/arch/parisc/include/uapi/asm/errno.h
index 8d94739d75c67c..8cbc07c1903e4c 100644
--- a/tools/arch/parisc/include/uapi/asm/errno.h
+++ b/tools/arch/parisc/include/uapi/asm/errno.h
@@ -36,6 +36,7 @@
 
 #define	EDOTDOT		66	/* RFS specific error */
 #define	EBADMSG		67	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EUSERS		68	/* Too many users */
 #define	EDQUOT		69	/* Quota exceeded */
 #define	ESTALE		70	/* Stale file handle */
@@ -62,6 +63,7 @@
 #define	ERESTART	175	/* Interrupted system call should be restarted */
 #define	ESTRPIPE	176	/* Streams pipe error */
 #define	EUCLEAN		177	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		178	/* Not a XENIX named type file */
 #define	ENAVAIL		179	/* No XENIX semaphores available */
 #define	EISNAM		180	/* Is a named type file */
diff --git a/tools/arch/sparc/include/uapi/asm/errno.h b/tools/arch/sparc/include/uapi/asm/errno.h
index 81a732b902ee38..4a41e7835fd5b8 100644
--- a/tools/arch/sparc/include/uapi/asm/errno.h
+++ b/tools/arch/sparc/include/uapi/asm/errno.h
@@ -48,6 +48,7 @@
 #define	ENOSR		74	/* Out of streams resources */
 #define	ENOMSG		75	/* No message of desired type */
 #define	EBADMSG		76	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EIDRM		77	/* Identifier removed */
 #define	EDEADLK		78	/* Resource deadlock would occur */
 #define	ENOLCK		79	/* No record locks available */
@@ -91,6 +92,7 @@
 #define	ENOTUNIQ	115	/* Name not unique on network */
 #define	ERESTART	116	/* Interrupted syscall should be restarted */
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */
diff --git a/tools/include/uapi/asm-generic/errno.h b/tools/include/uapi/asm-generic/errno.h
index cf9c51ac49f97e..92e7ae493ee315 100644
--- a/tools/include/uapi/asm-generic/errno.h
+++ b/tools/include/uapi/asm-generic/errno.h
@@ -55,6 +55,7 @@
 #define	EMULTIHOP	72	/* Multihop attempted */
 #define	EDOTDOT		73	/* RFS specific error */
 #define	EBADMSG		74	/* Not a data message */
+#define	EFSBADCRC	EBADMSG	/* Bad CRC detected */
 #define	EOVERFLOW	75	/* Value too large for defined data type */
 #define	ENOTUNIQ	76	/* Name not unique on network */
 #define	EBADFD		77	/* File descriptor in bad state */
@@ -98,6 +99,7 @@
 #define	EINPROGRESS	115	/* Operation now in progress */
 #define	ESTALE		116	/* Stale file handle */
 #define	EUCLEAN		117	/* Structure needs cleaning */
+#define	EFSCORRUPTED	EUCLEAN	/* Filesystem is corrupted */
 #define	ENOTNAM		118	/* Not a XENIX named type file */
 #define	ENAVAIL		119	/* No XENIX semaphores available */
 #define	EISNAM		120	/* Is a named type file */

[PATCH 2/6] fs: report filesystem and file I/O errors to fsnotify

[Darrick J. Wong]

From: Darrick J. Wong <djwong@kernel.org>

Create some wrapper code around struct super_block so that filesystems
have a standard way to queue filesystem metadata and file I/O error
reports to have them sent to fsnotify.

If a filesystem wants to provide an error number, it must supply only
negative error numbers.  These are stored internally as negative
numbers, but they are converted to positive error numbers before being
passed to fanotify, per the fanotify(7) manpage.  Implementations of
super_operations::report_error are passed the raw internal event data.

Note that we have to play some shenanigans with mempools and queue_work
so that the error handling doesn't happen outside of process context,
and the event handler functions (both ->report_error and fsnotify) can
handle file I/O error messages without having to worry about whatever
locks might be held.  This asynchronicity requires that unmount wait for
pending events to clear.

Add a new callback to the superblock operations structure so that
filesystem drivers can themselves respond to file I/O errors if they so
desire.  This will be used for an upcoming self-healing patchset for
XFS.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 include/linux/fs/super_types.h |    7 +
 include/linux/fserror.h        |   75 +++++++++++++++
 fs/Makefile                    |    2 
 fs/fserror.c                   |  194 ++++++++++++++++++++++++++++++++++++++++
 fs/super.c                     |    3 +
 5 files changed, 280 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/fserror.h
 create mode 100644 fs/fserror.c


diff --git a/include/linux/fs/super_types.h b/include/linux/fs/super_types.h
index 6bd3009e09b3b8..97a8552d8f2bc9 100644
--- a/include/linux/fs/super_types.h
+++ b/include/linux/fs/super_types.h
@@ -35,6 +35,7 @@ struct user_namespace;
 struct workqueue_struct;
 struct writeback_control;
 struct xattr_handler;
+struct fserror_event;
 
 extern struct super_block *blockdev_superblock;
 
@@ -124,6 +125,9 @@ struct super_operations {
 	 */
 	int (*remove_bdev)(struct super_block *sb, struct block_device *bdev);
 	void (*shutdown)(struct super_block *sb);
+
+	/* Report a filesystem error */
+	void (*report_error)(const struct fserror_event *event);
 };
 
 struct super_block {
@@ -268,6 +272,9 @@ struct super_block {
 	spinlock_t				s_inode_wblist_lock;
 	struct list_head			s_inodes_wb;	/* writeback inodes */
 	long					s_min_writeback_pages;
+
+	/* number of fserrors that are being sent to fsnotify/filesystems */
+	refcount_t				s_pending_errors;
 } __randomize_layout;
 
 /*
diff --git a/include/linux/fserror.h b/include/linux/fserror.h
new file mode 100644
index 00000000000000..5e1ad78c346e27
--- /dev/null
+++ b/include/linux/fserror.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2025 Oracle.  All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef _LINUX_FSERROR_H__
+#define _LINUX_FSERROR_H__
+
+void fserror_mount(struct super_block *sb);
+void fserror_unmount(struct super_block *sb);
+
+enum fserror_type {
+	/* pagecache I/O failed */
+	FSERR_BUFFERED_READ,
+	FSERR_BUFFERED_WRITE,
+
+	/* direct I/O failed */
+	FSERR_DIRECTIO_READ,
+	FSERR_DIRECTIO_WRITE,
+
+	/* out of band media error reported */
+	FSERR_DATA_LOST,
+
+	/* filesystem metadata */
+	FSERR_METADATA,
+};
+
+struct fserror_event {
+	struct work_struct work;
+	struct super_block *sb;
+	struct inode *inode;
+	loff_t pos;
+	u64 len;
+	enum fserror_type type;
+
+	/* negative error number */
+	int error;
+};
+
+void fserror_report(struct super_block *sb, struct inode *inode,
+		    enum fserror_type type, loff_t pos, u64 len, int error,
+		    gfp_t gfp);
+
+static inline void fserror_report_io(struct inode *inode,
+				     enum fserror_type type, loff_t pos,
+				     u64 len, int error, gfp_t gfp)
+{
+	fserror_report(inode->i_sb, inode, type, pos, len, error, gfp);
+}
+
+static inline void fserror_report_data_lost(struct inode *inode, loff_t pos,
+					    u64 len, gfp_t gfp)
+{
+	fserror_report(inode->i_sb, inode, FSERR_DATA_LOST, pos, len, -EIO,
+		       gfp);
+}
+
+static inline void fserror_report_file_metadata(struct inode *inode, int error,
+						gfp_t gfp)
+{
+	fserror_report(inode->i_sb, inode, FSERR_METADATA, 0, 0, error, gfp);
+}
+
+static inline void fserror_report_metadata(struct super_block *sb, int error,
+					   gfp_t gfp)
+{
+	fserror_report(sb, NULL, FSERR_METADATA, 0, 0, error, gfp);
+}
+
+static inline void fserror_report_shutdown(struct super_block *sb, gfp_t gfp)
+{
+	fserror_report(sb, NULL, FSERR_METADATA, 0, 0, -ESHUTDOWN, gfp);
+}
+
+#endif /* _LINUX_FSERROR_H__ */
diff --git a/fs/Makefile b/fs/Makefile
index a04274a3c85420..f238cc5ea2e9d7 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -16,7 +16,7 @@ obj-y :=	open.o read_write.o file_table.o super.o \
 		stack.o fs_struct.o statfs.o fs_pin.o nsfs.o \
 		fs_dirent.o fs_context.o fs_parser.o fsopen.o init.o \
 		kernel_read_file.o mnt_idmapping.o remap_range.o pidfs.o \
-		file_attr.o
+		file_attr.o fserror.o
 
 obj-$(CONFIG_BUFFER_HEAD)	+= buffer.o mpage.o
 obj-$(CONFIG_PROC_FS)		+= proc_namespace.o
diff --git a/fs/fserror.c b/fs/fserror.c
new file mode 100644
index 00000000000000..06ca86adab9b76
--- /dev/null
+++ b/fs/fserror.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2025 Oracle.  All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#include <linux/fs.h>
+#include <linux/fsnotify.h>
+#include <linux/mempool.h>
+#include <linux/fserror.h>
+
+#define FSERROR_DEFAULT_EVENT_POOL_SIZE		(32)
+
+static struct mempool fserror_events_pool;
+
+void fserror_mount(struct super_block *sb)
+{
+	/*
+	 * The pending error counter is biased by 1 so that we don't wake_var
+	 * until we're actually trying to unmount.
+	 */
+	refcount_set(&sb->s_pending_errors, 1);
+}
+
+void fserror_unmount(struct super_block *sb)
+{
+	/*
+	 * If we don't drop the pending error count to zero, then wait for it
+	 * to drop below 1, which means that the pending errors cleared and
+	 * hopefully we didn't saturate with 1 billion+ concurrent events.
+	 */
+	if (!refcount_dec_and_test(&sb->s_pending_errors))
+		wait_var_event(&sb->s_pending_errors,
+			       refcount_read(&sb->s_pending_errors) < 1);
+}
+
+static inline void fserror_pending_dec(struct super_block *sb)
+{
+	if (refcount_dec_and_test(&sb->s_pending_errors))
+		wake_up_var(&sb->s_pending_errors);
+}
+
+static inline void fserror_free_event(struct fserror_event *event)
+{
+	fserror_pending_dec(event->sb);
+	mempool_free(event, &fserror_events_pool);
+}
+
+static void fserror_worker(struct work_struct *work)
+{
+	struct fserror_event *event =
+			container_of(work, struct fserror_event, work);
+	struct super_block *sb = event->sb;
+
+	if (sb->s_flags & SB_ACTIVE) {
+		struct fs_error_report report = {
+			/* send positive error number to userspace */
+			.error = -event->error,
+			.inode = event->inode,
+			.sb = event->sb,
+		};
+
+		if (sb->s_op->report_error)
+			sb->s_op->report_error(event);
+
+		fsnotify(FS_ERROR, &report, FSNOTIFY_EVENT_ERROR, NULL, NULL,
+			 NULL, 0);
+	}
+
+	iput(event->inode);
+	fserror_free_event(event);
+}
+
+static inline struct fserror_event *fserror_alloc_event(struct super_block *sb,
+							gfp_t gfp_flags)
+{
+	struct fserror_event *event = NULL;
+
+	/*
+	 * If pending_errors already reached zero or is no longer active,
+	 * the superblock is being deactivated so there's no point in
+	 * continuing.
+	 *
+	 * The order of the check of s_pending_errors and SB_ACTIVE are
+	 * mandated by order of accesses in generic_shutdown_super and
+	 * fserror_unmount.  Barriers are implicitly provided by the refcount
+	 * manipulations in this function and fserror_unmount.
+	 */
+	if (!refcount_inc_not_zero(&sb->s_pending_errors))
+		return NULL;
+	if (!(sb->s_flags & SB_ACTIVE))
+		goto out_pending;
+
+	event = mempool_alloc(&fserror_events_pool, gfp_flags);
+	if (!event)
+		goto out_pending;
+
+	/* mempool_alloc doesn't support GFP_ZERO */
+	memset(event, 0, sizeof(*event));
+	event->sb = sb;
+	INIT_WORK(&event->work, fserror_worker);
+
+	return event;
+
+out_pending:
+	fserror_pending_dec(sb);
+	return NULL;
+}
+
+/**
+ * fserror_report - report a filesystem error of some kind
+ *
+ * @sb:		superblock of the filesystem
+ * @inode:	inode within that filesystem, if applicable
+ * @type:	type of error encountered
+ * @pos:	start of inode range affected, if applicable
+ * @len:	length of inode range affected, if applicable
+ * @error:	error number encountered, must be negative
+ * @gfp:	memory allocation flags for conveying the event to a worker,
+ *		since this function can be called from atomic contexts
+ *
+ * Report details of a filesystem error to the super_operations::report_error
+ * callback if present; and to fsnotify for distribution to userspace.  @sb,
+ * @gfp, @type, and @error must all be specified.  For file I/O errors, the
+ * @inode, @pos, and @len fields must also be specified.  For file metadata
+ * errors, @inode must be specified.  If @inode is not NULL, then @inode->i_sb
+ * must point to @sb.
+ *
+ * Reporting work is deferred to a workqueue to ensure that ->report_error is
+ * called from process context without any locks held.  An active reference to
+ * the inode is maintained until event handling is complete, and unmount will
+ * wait for queued events to drain.
+ */
+void fserror_report(struct super_block *sb, struct inode *inode,
+		    enum fserror_type type, loff_t pos, u64 len, int error,
+		    gfp_t gfp)
+{
+	struct fserror_event *event;
+
+	/* sb and inode must be from the same filesystem */
+	WARN_ON_ONCE(inode && inode->i_sb != sb);
+
+	/* error number must be negative */
+	WARN_ON_ONCE(error >= 0);
+
+	event = fserror_alloc_event(sb, gfp);
+	if (!event)
+		goto lost;
+
+	event->type = type;
+	event->pos = pos;
+	event->len = len;
+	event->error = error;
+
+	/*
+	 * Can't iput from non-sleeping context, so grabbing another reference
+	 * to the inode must be the last thing before submitting the event.
+	 */
+	if (inode) {
+		event->inode = igrab(inode);
+		if (!event->inode)
+			goto lost_event;
+	}
+
+	/*
+	 * Use schedule_work here even if we're already in process context so
+	 * that fsnotify and super_operations::report_error implementations are
+	 * guaranteed to run in process context without any locks held.  Since
+	 * errors are supposed to be rare, the overhead shouldn't kill us any
+	 * more than the failing device will.
+	 */
+	schedule_work(&event->work);
+	return;
+
+lost_event:
+	fserror_free_event(event);
+lost:
+	if (inode)
+		pr_err_ratelimited(
+ "%s: lost file I/O error report for ino %lu type %u pos 0x%llx len 0x%llx error %d",
+		       sb->s_id, inode->i_ino, type, pos, len, error);
+	else
+		pr_err_ratelimited(
+ "%s: lost filesystem error report for type %u error %d",
+		       sb->s_id, type, error);
+}
+EXPORT_SYMBOL_GPL(fserror_report);
+
+static int __init fserror_init(void)
+{
+	return mempool_init_kmalloc_pool(&fserror_events_pool,
+					 FSERROR_DEFAULT_EVENT_POOL_SIZE,
+					 sizeof(struct fserror_event));
+}
+fs_initcall(fserror_init);
diff --git a/fs/super.c b/fs/super.c
index 3d85265d14001d..b13c1fd6a6f422 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -36,6 +36,7 @@
 #include <linux/lockdep.h>
 #include <linux/user_namespace.h>
 #include <linux/fs_context.h>
+#include <linux/fserror.h>
 #include <uapi/linux/mount.h>
 #include "internal.h"
 
@@ -363,6 +364,7 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags,
 	spin_lock_init(&s->s_inode_list_lock);
 	INIT_LIST_HEAD(&s->s_inodes_wb);
 	spin_lock_init(&s->s_inode_wblist_lock);
+	fserror_mount(s);
 
 	s->s_count = 1;
 	atomic_set(&s->s_active, 1);
@@ -622,6 +624,7 @@ void generic_shutdown_super(struct super_block *sb)
 		sync_filesystem(sb);
 		sb->s_flags &= ~SB_ACTIVE;
 
+		fserror_unmount(sb);
 		cgroup_writeback_umount(sb);
 
 		/* Evict all inodes with zero refcount. */

[PATCH 3/6] iomap: report file I/O errors to the VFS

[Darrick J. Wong]

From: Darrick J. Wong <djwong@kernel.org>

Wire up iomap so that it reports all file read and write errors to the
VFS (and hence fsnotify) via the new fserror mechanism.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/iomap/buffered-io.c |   23 ++++++++++++++++++++++-
 fs/iomap/direct-io.c   |   12 ++++++++++++
 fs/iomap/ioend.c       |    6 ++++++
 3 files changed, 40 insertions(+), 1 deletion(-)


diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index fd9a2cf9562024..4a5f96a7c39042 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -8,6 +8,7 @@
 #include <linux/writeback.h>
 #include <linux/swap.h>
 #include <linux/migrate.h>
+#include <linux/fserror.h>
 #include "internal.h"
 #include "trace.h"
 
@@ -371,8 +372,11 @@ static int iomap_read_inline_data(const struct iomap_iter *iter,
 	if (folio_test_uptodate(folio))
 		return 0;
 
-	if (WARN_ON_ONCE(size > iomap->length))
+	if (WARN_ON_ONCE(size > iomap->length)) {
+		fserror_report_io(iter->inode, FSERR_BUFFERED_READ,
+				  iomap->offset, size, -EIO, GFP_NOFS);
 		return -EIO;
+	}
 	if (offset > 0)
 		ifs_alloc(iter->inode, folio, iter->flags);
 
@@ -399,6 +403,11 @@ void iomap_finish_folio_read(struct folio *folio, size_t off, size_t len,
 		spin_unlock_irqrestore(&ifs->state_lock, flags);
 	}
 
+	if (error)
+		fserror_report_io(folio->mapping->host, FSERR_BUFFERED_READ,
+				  folio_pos(folio) + off, len, error,
+				  GFP_ATOMIC);
+
 	if (finished)
 		folio_end_read(folio, uptodate);
 }
@@ -540,6 +549,10 @@ static int iomap_read_folio_iter(struct iomap_iter *iter,
 			if (!*bytes_submitted)
 				iomap_read_init(folio);
 			ret = ctx->ops->read_folio_range(iter, ctx, plen);
+			if (ret < 0)
+				fserror_report_io(iter->inode,
+						  FSERR_BUFFERED_READ, pos,
+						  plen, ret, GFP_NOFS);
 			if (ret)
 				return ret;
 			*bytes_submitted += plen;
@@ -815,6 +828,10 @@ static int __iomap_write_begin(const struct iomap_iter *iter,
 			else
 				status = iomap_bio_read_folio_range_sync(iter,
 						folio, block_start, plen);
+			if (status < 0)
+				fserror_report_io(iter->inode,
+						  FSERR_BUFFERED_READ, pos,
+						  len, status, GFP_NOFS);
 			if (status)
 				return status;
 		}
@@ -1825,6 +1842,7 @@ int iomap_writeback_folio(struct iomap_writepage_ctx *wpc, struct folio *folio)
 	u64 pos = folio_pos(folio);
 	u64 end_pos = pos + folio_size(folio);
 	u64 end_aligned = 0;
+	loff_t orig_pos = pos;
 	size_t bytes_submitted = 0;
 	int error = 0;
 	u32 rlen;
@@ -1868,6 +1886,9 @@ int iomap_writeback_folio(struct iomap_writepage_ctx *wpc, struct folio *folio)
 
 	if (bytes_submitted)
 		wpc->nr_folios++;
+	if (error && pos > orig_pos)
+		fserror_report_io(inode, FSERR_BUFFERED_WRITE, orig_pos, 0,
+				  error, GFP_NOFS);
 
 	/*
 	 * We can have dirty bits set past end of file in page_mkwrite path
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 8e273408453a9c..a06c73eaa8901b 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -7,6 +7,7 @@
 #include <linux/pagemap.h>
 #include <linux/iomap.h>
 #include <linux/task_io_accounting_ops.h>
+#include <linux/fserror.h>
 #include "internal.h"
 #include "trace.h"
 
@@ -78,6 +79,13 @@ static void iomap_dio_submit_bio(const struct iomap_iter *iter,
 	}
 }
 
+static inline enum fserror_type iomap_dio_err_type(const struct iomap_dio *dio)
+{
+	if (dio->flags & IOMAP_DIO_WRITE)
+		return FSERR_DIRECTIO_WRITE;
+	return FSERR_DIRECTIO_READ;
+}
+
 ssize_t iomap_dio_complete(struct iomap_dio *dio)
 {
 	const struct iomap_dio_ops *dops = dio->dops;
@@ -87,6 +95,10 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio)
 
 	if (dops && dops->end_io)
 		ret = dops->end_io(iocb, dio->size, ret, dio->flags);
+	if (dio->error)
+		fserror_report_io(file_inode(iocb->ki_filp),
+				  iomap_dio_err_type(dio), offset, dio->size,
+				  dio->error, GFP_NOFS);
 
 	if (likely(!ret)) {
 		ret = dio->size;
diff --git a/fs/iomap/ioend.c b/fs/iomap/ioend.c
index 86f44922ed3b6a..5b27ee98896707 100644
--- a/fs/iomap/ioend.c
+++ b/fs/iomap/ioend.c
@@ -6,6 +6,7 @@
 #include <linux/list_sort.h>
 #include <linux/pagemap.h>
 #include <linux/writeback.h>
+#include <linux/fserror.h>
 #include "internal.h"
 #include "trace.h"
 
@@ -55,6 +56,11 @@ static u32 iomap_finish_ioend_buffered(struct iomap_ioend *ioend)
 
 	/* walk all folios in bio, ending page IO on them */
 	bio_for_each_folio_all(fi, bio) {
+		if (ioend->io_error)
+			fserror_report_io(inode, FSERR_BUFFERED_WRITE,
+					  folio_pos(fi.folio) + fi.offset,
+					  fi.length, ioend->io_error,
+					  GFP_ATOMIC);
 		iomap_finish_folio_write(inode, fi.folio, fi.length);
 		folio_count++;
 	}

[PATCH 4/6] xfs: report fs metadata errors via fsnotify

[Darrick J. Wong]

From: Darrick J. Wong <djwong@kernel.org>

Report filesystem corruption problems to the fserror helpers so that
fsnotify can also convey metadata problems to userspace.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_fsops.c  |    4 ++++
 fs/xfs/xfs_health.c |   14 ++++++++++++++
 2 files changed, 18 insertions(+)


diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 0ada735693945c..b7c21f68edc78d 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -26,6 +26,8 @@
 #include "xfs_rtrefcount_btree.h"
 #include "xfs_metafile.h"
 
+#include <linux/fserror.h>
+
 /*
  * Write new AG headers to disk. Non-transactional, but need to be
  * written and completed prior to the growfs transaction being logged.
@@ -540,6 +542,8 @@ xfs_do_force_shutdown(
 		"Please unmount the filesystem and rectify the problem(s)");
 	if (xfs_error_level >= XFS_ERRLEVEL_HIGH)
 		xfs_stack_trace();
+
+	fserror_report_shutdown(mp->m_super, GFP_KERNEL);
 }
 
 /*
diff --git a/fs/xfs/xfs_health.c b/fs/xfs/xfs_health.c
index 3c1557fb1cf083..fbb8886c72fe5e 100644
--- a/fs/xfs/xfs_health.c
+++ b/fs/xfs/xfs_health.c
@@ -20,6 +20,8 @@
 #include "xfs_quota_defs.h"
 #include "xfs_rtgroup.h"
 
+#include <linux/fserror.h>
+
 static void
 xfs_health_unmount_group(
 	struct xfs_group	*xg,
@@ -111,6 +113,8 @@ xfs_fs_mark_sick(
 	spin_lock(&mp->m_sb_lock);
 	mp->m_fs_sick |= mask;
 	spin_unlock(&mp->m_sb_lock);
+
+	fserror_report_metadata(mp->m_super, -EFSCORRUPTED, GFP_NOFS);
 }
 
 /* Mark per-fs metadata as having been checked and found unhealthy by fsck. */
@@ -126,6 +130,8 @@ xfs_fs_mark_corrupt(
 	mp->m_fs_sick |= mask;
 	mp->m_fs_checked |= mask;
 	spin_unlock(&mp->m_sb_lock);
+
+	fserror_report_metadata(mp->m_super, -EFSCORRUPTED, GFP_NOFS);
 }
 
 /* Mark a per-fs metadata healed. */
@@ -198,6 +204,8 @@ xfs_group_mark_sick(
 	spin_lock(&xg->xg_state_lock);
 	xg->xg_sick |= mask;
 	spin_unlock(&xg->xg_state_lock);
+
+	fserror_report_metadata(xg->xg_mount->m_super, -EFSCORRUPTED, GFP_NOFS);
 }
 
 /*
@@ -215,6 +223,8 @@ xfs_group_mark_corrupt(
 	xg->xg_sick |= mask;
 	xg->xg_checked |= mask;
 	spin_unlock(&xg->xg_state_lock);
+
+	fserror_report_metadata(xg->xg_mount->m_super, -EFSCORRUPTED, GFP_NOFS);
 }
 
 /*
@@ -287,6 +297,8 @@ xfs_inode_mark_sick(
 	spin_lock(&VFS_I(ip)->i_lock);
 	inode_state_clear(VFS_I(ip), I_DONTCACHE);
 	spin_unlock(&VFS_I(ip)->i_lock);
+
+	fserror_report_file_metadata(VFS_I(ip), -EFSCORRUPTED, GFP_NOFS);
 }
 
 /* Mark inode metadata as having been checked and found unhealthy by fsck. */
@@ -311,6 +323,8 @@ xfs_inode_mark_corrupt(
 	spin_lock(&VFS_I(ip)->i_lock);
 	inode_state_clear(VFS_I(ip), I_DONTCACHE);
 	spin_unlock(&VFS_I(ip)->i_lock);
+
+	fserror_report_file_metadata(VFS_I(ip), -EFSCORRUPTED, GFP_NOFS);
 }
 
 /* Mark parts of an inode healed. */

[PATCH 5/6] xfs: translate fsdax media errors into file "data lost" errors when convenient

[Darrick J. Wong]

From: Darrick J. Wong <djwong@kernel.org>

Translate fsdax persistent failure notifications into file data loss
events when it's convenient, aka when the inode is already incore.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_notify_failure.c |    4 ++++
 1 file changed, 4 insertions(+)


diff --git a/fs/xfs/xfs_notify_failure.c b/fs/xfs/xfs_notify_failure.c
index b1767288994206..6d5002413c2cb4 100644
--- a/fs/xfs/xfs_notify_failure.c
+++ b/fs/xfs/xfs_notify_failure.c
@@ -26,6 +26,7 @@
 #include <linux/mm.h>
 #include <linux/dax.h>
 #include <linux/fs.h>
+#include <linux/fserror.h>
 
 struct xfs_failure_info {
 	xfs_agblock_t		startblock;
@@ -116,6 +117,9 @@ xfs_dax_failure_fn(
 		invalidate_inode_pages2_range(mapping, pgoff,
 					      pgoff + pgcnt - 1);
 
+	fserror_report_data_lost(VFS_I(ip), (u64)pgoff << PAGE_SHIFT,
+			(u64)pgcnt << PAGE_SHIFT, GFP_NOFS);
+
 	xfs_irele(ip);
 	return error;
 }

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

[Darrick J. Wong]

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>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 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);
 }

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

[Gabriel Krisman Bertazi]

"Darrick J. Wong" <djwong@kernel.org> writes:

> 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>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jan Kara <jack@suse.cz>
> ---
>  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);
>  }
>

Perhaps also delete fsnotify_sb_error after this patch since it is now
implemented by fserror_worker and, if I follow correctly, we don't want
it to be called without the shutdown protection mechanism.

-- 
Gabriel Krisman Bertazi

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

[Darrick J. Wong]

On Mon, Jan 12, 2026 at 07:56:09PM -0500, Gabriel Krisman Bertazi wrote:
> "Darrick J. Wong" <djwong@kernel.org> writes:
> 
> > 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>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > Reviewed-by: Jan Kara <jack@suse.cz>
> > ---
> >  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);
> >  }
> >
> 
> Perhaps also delete fsnotify_sb_error after this patch since it is now
> implemented by fserror_worker and, if I follow correctly, we don't want
> it to be called without the shutdown protection mechanism.

<nod> I was planning to ask Linus if I could do that as a treewide
cleanup at the end of the whichever merge window integrates this, just
in case someone else adds a fsnotify_sb_error call to their filesystem
during that same merge window.

--D

> -- 
> Gabriel Krisman Bertazi
> 

Re: [PATCH 2/6] fs: report filesystem and file I/O errors to fsnotify

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCHSET v5] fs: generic file IO error reporting

[Christian Brauner]

On Mon, 12 Jan 2026 16:31:03 -0800, Darrick J. Wong wrote:
> This patchset adds some generic helpers so that filesystems can report
> errors to fsnotify in a standard way.  Then it adapts iomap to use the
> generic helpers so that any iomap-enabled filesystem can report I/O
> errors through this mechanism as well.  Finally, it makes XFS report
> metadata errors through this mechanism in much the same way that ext4
> does now.
> 
> [...]

Applied to the vfs-7.0.fserror branch of the vfs/vfs.git tree.
Patches in the vfs-7.0.fserror branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-7.0.fserror

[1/6] uapi: promote EFSCORRUPTED and EUCLEAN to errno.h
      https://git.kernel.org/vfs/vfs/c/602544773763
[2/6] fs: report filesystem and file I/O errors to fsnotify
      https://git.kernel.org/vfs/vfs/c/21945e6cb516
[3/6] iomap: report file I/O errors to the VFS
      https://git.kernel.org/vfs/vfs/c/a9d573ee88af
[4/6] xfs: report fs metadata errors via fsnotify
      https://git.kernel.org/vfs/vfs/c/efd87a100729
[5/6] xfs: translate fsdax media errors into file "data lost" errors when convenient
      https://git.kernel.org/vfs/vfs/c/94503211d2fd
[6/6] ext4: convert to new fserror helpers
      https://git.kernel.org/vfs/vfs/c/81d2e13a57c9

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

[Theodore Tso]

On Mon, Jan 12, 2026 at 04:32:27PM -0800, 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>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jan Kara <jack@suse.cz>

Acked-by: Theodore Ts'o <tytso@mit.edu>