Re: [PATCH 09/11] ext4: Send notifications on error

From: Amir Goldstein <amir73il@gmail.com>
To: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: kernel@collabora.com, "Darrick J . Wong" <djwong@kernel.org>,
	"Theodore Ts'o" <tytso@mit.edu>,
	Dave Chinner <david@fromorbit.com>, Jan Kara <jack@suse.com>,
	David Howells <dhowells@redhat.com>,
	Khazhismel Kumykov <khazhy@google.com>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Ext4 <linux-ext4@vger.kernel.org>
Subject: Re: [PATCH 09/11] ext4: Send notifications on error
Date: Fri, 21 May 2021 12:44:29 +0300	[thread overview]
Message-ID: <CAOQ4uxj+J7bA-7MKvv30jPAOGqjX7fpcKxC3RudXmTG2y+vxXw@mail.gmail.com> (raw)
In-Reply-To: <20210521024134.1032503-10-krisman@collabora.com>

On Fri, May 21, 2021 at 5:42 AM Gabriel Krisman Bertazi
<krisman@collabora.com> wrote:
>
> Send a FS_ERROR message via fsnotify to a userspace monitoring tool
> whenever a ext4 error condition is triggered.  This follows the existing
> error conditions in ext4, so it is hooked to the ext4_error* functions.
>
> It also follows the current dmesg reporting in the format.  The
> filesystem message is composed mostly by the string that would be
> otherwise printed in dmesg.
>
> A new ext4 specific record format is exposed in the uapi, such that a
> monitoring tool knows what to expect when listening errors of an ext4
> filesystem.
>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>

Looks fine.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>

> ---
>  fs/ext4/super.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 7dc94f3e18e6..a8c0ac2c3e4c 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -46,6 +46,7 @@
>  #include <linux/part_stat.h>
>  #include <linux/kthread.h>
>  #include <linux/freezer.h>
> +#include <linux/fsnotify.h>
>
>  #include "ext4.h"
>  #include "ext4_extents.h"      /* Needed for trace points definition */
> @@ -752,6 +753,8 @@ void __ext4_error(struct super_block *sb, const char *function,
>                        sb->s_id, function, line, current->comm, &vaf);
>                 va_end(args);
>         }
> +       fsnotify_error_event(sb, NULL, error);
> +
>         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
>  }
>
> @@ -782,6 +785,8 @@ void __ext4_error_inode(struct inode *inode, const char *function,
>                                current->comm, &vaf);
>                 va_end(args);
>         }
> +       fsnotify_error_event(inode->i_sb, inode, error);
> +
>         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
>                           function, line);
>  }
> @@ -820,6 +825,8 @@ void __ext4_error_file(struct file *file, const char *function,
>                                current->comm, path, &vaf);
>                 va_end(args);
>         }
> +       fsnotify_error_event(inode->i_sb, inode, EFSCORRUPTED);
> +
>         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
>                           function, line);
>  }
> @@ -887,6 +894,7 @@ 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_error_event(sb, sb->s_root->d_inode, errno);
>
>         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
>  }
> --
> 2.31.0
>