Clarify the conditions for getting the -EXDEV and -ENODEV errors. Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- Changes since v1: - Fix review comments [1] [1] https://lore.kernel.org/linux-fsdevel/20241101130732.xzpottv5ru63w4wd@devuan/ man/man2/fanotify_mark.2 | 27 +++++++++++++++++++++------ man/man7/fanotify.7 | 11 +++++++++++ 2 files changed, 32 insertions(+), 6 deletions(-) diff --git a/man/man2/fanotify_mark.2 b/man/man2/fanotify_mark.2 index fc9b83459..47cafb21c 100644 --- a/man/man2/fanotify_mark.2 +++ b/man/man2/fanotify_mark.2 @@ -659,17 +659,16 @@ The filesystem object indicated by .I dirfd and .I pathname -is not associated with a filesystem that supports +is associated with a filesystem that reports zero .I fsid (e.g., .BR fuse (4)). -.BR tmpfs (5) -did not support -.I fsid -prior to Linux 5.13. -.\" commit 59cda49ecf6c9a32fae4942420701b6e087204f6 This error can be returned only with an fanotify group that identifies filesystem objects by file handles. +Since Linux 6.8, +.\" commit 30ad1938326bf9303ca38090339d948975a626f5 +this error can be returned +when trying to add a mount or filesystem mark. .TP .B ENOENT The filesystem object indicated by @@ -768,6 +767,22 @@ which uses a different than its root superblock. This error can be returned only with an fanotify group that identifies filesystem objects by file handles. +Since Linux 6.8, +.\" commit 30ad1938326bf9303ca38090339d948975a626f5 +this error will be returned +when trying to add a mount or filesystem mark on a subvolume, +when trying to add inode marks in different subvolumes, +or when trying to add inode marks in a +.BR btrfs (5) +subvolume and in another filesystem. +Since Linux 6.8, +.\" commit 30ad1938326bf9303ca38090339d948975a626f5 +this error will also be returned +when trying to add marks in different filesystems, +where one of the filesystems reports zero +.I fsid +(e.g., +.BR fuse (4)). .SH STANDARDS Linux. .SH HISTORY diff --git a/man/man7/fanotify.7 b/man/man7/fanotify.7 index 449af949c..b270f3c99 100644 --- a/man/man7/fanotify.7 +++ b/man/man7/fanotify.7 @@ -575,6 +575,17 @@ and contains the same value as .I f_fsid when calling .BR statfs (2). +Note that some filesystems (e.g., +.BR fuse (4)) +report zero +.IR fsid . +In these cases, +it is not possible to use +.I fsid +to associate the event with a specific filesystem instance, +so monitoring different filesystem instances that report zero +.I fsid +with the same fanotify group is not supported. .TP .I handle This field contains a variable-length structure of type -- 2.34.1
