| Message ID | 20210426184201.4177978-10-krisman@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | File system wide monitoring | expand |
On Mon, Apr 26, 2021 at 9:42 PM Gabriel Krisman Bertazi <krisman@collabora.com> wrote: > > This record describes a fs error in a fs agnostic way. It will be send > back to userspace in response to a FSNOTIFY_EVENT_ERROR for groups with > the FAN_ERROR mark. It's not a mark, it's an event, so: "...for groups with the FAN_ERROR event in their mark mask" > > Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> > --- > fs/notify/fanotify/fanotify.h | 16 ++++++++++++++++ > fs/notify/fanotify/fanotify_user.c | 28 ++++++++++++++++++++++++++++ > include/uapi/linux/fanotify.h | 10 ++++++++++ > 3 files changed, 54 insertions(+) > > diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h > index 47299e3d6efd..4cb9dd31f084 100644 > --- a/fs/notify/fanotify/fanotify.h > +++ b/fs/notify/fanotify/fanotify.h > @@ -179,6 +179,22 @@ FANOTIFY_NE(struct fanotify_event *event) > return container_of(event, struct fanotify_name_event, fae); > } > > +struct fanotify_error_event { > + struct fanotify_event fae; > + int error; > + __kernel_fsid_t fsid; > + > + int fs_data_size; > + /* Must be the last item in the structure */ > + char fs_data[0]; > +}; > + > +static inline struct fanotify_error_event * > +FANOTIFY_EE(struct fanotify_event *event) > +{ > + return container_of(event, struct fanotify_error_event, fae); > +} > + > static inline __kernel_fsid_t *fanotify_event_fsid(struct fanotify_event *event) > { > if (event->type == FANOTIFY_EVENT_TYPE_FID) > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c > index 5031198bf7db..21162d347bd1 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -64,6 +64,11 @@ static int fanotify_fid_info_len(int fh_len, int name_len) > return roundup(FANOTIFY_INFO_HDR_LEN + info_len, FANOTIFY_EVENT_ALIGN); > } > > +static size_t fanotify_error_info_len(struct fanotify_error_event *fee) > +{ > + return sizeof(struct fanotify_event_info_error); > +} > + > static size_t fanotify_event_len(struct fanotify_event *event, > unsigned int fid_mode) > { > @@ -232,6 +237,29 @@ static int process_access_response(struct fsnotify_group *group, > return -ENOENT; > } > > +static size_t copy_error_info_to_user(struct fanotify_error_event *fee, > + char __user *buf, int count) > +{ > + struct fanotify_event_info_error info; > + > + info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR; > + info.hdr.pad = 0; > + info.hdr.len = fanotify_error_info_len(fee); > + > + if (WARN_ON(count < info.hdr.len)) > + return -EFAULT; > + > + info.version = FANOTIFY_EVENT_INFO_ERROR_VERS_1; > + info.error = fee->error; > + info.fsid = fee->fsid; > + > + if (copy_to_user(buf, &info, sizeof(info))) > + return -EFAULT; > + > + return info.hdr.len; > + > +} > + > static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, > int info_type, const char *name, size_t name_len, > char __user *buf, size_t count) > diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h > index b283531549f1..cc9a1fa80e30 100644 > --- a/include/uapi/linux/fanotify.h > +++ b/include/uapi/linux/fanotify.h > @@ -124,6 +124,7 @@ struct fanotify_event_metadata { > #define FAN_EVENT_INFO_TYPE_FID 1 > #define FAN_EVENT_INFO_TYPE_DFID_NAME 2 > #define FAN_EVENT_INFO_TYPE_DFID 3 > +#define FAN_EVENT_INFO_TYPE_ERROR 4 > > /* Variable length info record following event metadata */ > struct fanotify_event_info_header { > @@ -149,6 +150,15 @@ struct fanotify_event_info_fid { > unsigned char handle[0]; > }; > > +#define FANOTIFY_EVENT_INFO_ERROR_VERS_1 1 Honestly, this struct is too simple to have a 'version'. The format of this simple struct is already defined by FAN_EVENT_INFO_TYPE_ERROR and if we want to change the reported info in the future, we can use FAN_EVENT_INFO_TYPE_ERROR_V2. In fact, I suggest to name the type FAN_EVENT_INFO_TYPE_FS_ERROR to differentiate from a future FAN_EVENT_INFO_TYPE_WB_ERROR > + > +struct fanotify_event_info_error { > + struct fanotify_event_info_header hdr; > + int version; > + int error; > + __kernel_fsid_t fsid; > +}; I suggest to put an error seq counter in this struct. The per-sb seq counter can be provided by the filesystem or by fsnotify. Thanks, Amir.
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 47299e3d6efd..4cb9dd31f084 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -179,6 +179,22 @@ FANOTIFY_NE(struct fanotify_event *event) return container_of(event, struct fanotify_name_event, fae); } +struct fanotify_error_event { + struct fanotify_event fae; + int error; + __kernel_fsid_t fsid; + + int fs_data_size; + /* Must be the last item in the structure */ + char fs_data[0]; +}; + +static inline struct fanotify_error_event * +FANOTIFY_EE(struct fanotify_event *event) +{ + return container_of(event, struct fanotify_error_event, fae); +} + static inline __kernel_fsid_t *fanotify_event_fsid(struct fanotify_event *event) { if (event->type == FANOTIFY_EVENT_TYPE_FID) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 5031198bf7db..21162d347bd1 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -64,6 +64,11 @@ static int fanotify_fid_info_len(int fh_len, int name_len) return roundup(FANOTIFY_INFO_HDR_LEN + info_len, FANOTIFY_EVENT_ALIGN); } +static size_t fanotify_error_info_len(struct fanotify_error_event *fee) +{ + return sizeof(struct fanotify_event_info_error); +} + static size_t fanotify_event_len(struct fanotify_event *event, unsigned int fid_mode) { @@ -232,6 +237,29 @@ static int process_access_response(struct fsnotify_group *group, return -ENOENT; } +static size_t copy_error_info_to_user(struct fanotify_error_event *fee, + char __user *buf, int count) +{ + struct fanotify_event_info_error info; + + info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR; + info.hdr.pad = 0; + info.hdr.len = fanotify_error_info_len(fee); + + if (WARN_ON(count < info.hdr.len)) + return -EFAULT; + + info.version = FANOTIFY_EVENT_INFO_ERROR_VERS_1; + info.error = fee->error; + info.fsid = fee->fsid; + + if (copy_to_user(buf, &info, sizeof(info))) + return -EFAULT; + + return info.hdr.len; + +} + static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, int info_type, const char *name, size_t name_len, char __user *buf, size_t count) diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index b283531549f1..cc9a1fa80e30 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -124,6 +124,7 @@ struct fanotify_event_metadata { #define FAN_EVENT_INFO_TYPE_FID 1 #define FAN_EVENT_INFO_TYPE_DFID_NAME 2 #define FAN_EVENT_INFO_TYPE_DFID 3 +#define FAN_EVENT_INFO_TYPE_ERROR 4 /* Variable length info record following event metadata */ struct fanotify_event_info_header { @@ -149,6 +150,15 @@ struct fanotify_event_info_fid { unsigned char handle[0]; }; +#define FANOTIFY_EVENT_INFO_ERROR_VERS_1 1 + +struct fanotify_event_info_error { + struct fanotify_event_info_header hdr; + int version; + int error; + __kernel_fsid_t fsid; +}; + struct fanotify_response { __s32 fd; __u32 response;
This record describes a fs error in a fs agnostic way. It will be send back to userspace in response to a FSNOTIFY_EVENT_ERROR for groups with the FAN_ERROR mark. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> --- fs/notify/fanotify/fanotify.h | 16 ++++++++++++++++ fs/notify/fanotify/fanotify_user.c | 28 ++++++++++++++++++++++++++++ include/uapi/linux/fanotify.h | 10 ++++++++++ 3 files changed, 54 insertions(+)