The function "fuse_fsnotify_send_request" is responsible for sending an fsnotify FUSE request to the FUSE server (virtiofsd).
The request contains all the information that is stored within the "fuse_notify_fsnotify_in" struct, i.e., the event mask for the inotify watch, the action to be performed on the watch (create, modify or delete) and the group identifier which is essentially the 64bit (fsnotify_group) pointer that corresponds to one inotify instance created by a user space process. Since each group identifier is unique, the FUSE server can create an equal number of inotify instances to the ones created by the user space processes. Signed-off-by: Ioannis Angelakopoulos <[email protected]> --- fs/fuse/dev.c | 37 +++++++++++++++++++++++++++++++++++++ fs/fuse/fuse_i.h | 3 +++ 2 files changed, 40 insertions(+) diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index dde341a6388a..89eea8abac4b 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1795,6 +1795,43 @@ static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code, } } +/* Send a request for a watch placement to the FUSE server */ +int fuse_fsnotify_send_request(struct inode *inode, uint32_t mask, + uint32_t action, uint64_t group) +{ + struct fuse_mount *fm = get_fuse_mount(inode); + struct fuse_notify_fsnotify_in inarg; + int err; + FUSE_ARGS(args); + + /* The server does not support remote fsnotify events */ + if (fm->fc->no_fsnotify) + return 0; + + /* + * Send the mask the action (remove, add, modify) and the + * unique identifier that is the fsnotify group that is + * interested in the watch to the FUSE server + */ + memset(&inarg, 0, sizeof(struct fuse_notify_fsnotify_in)); + inarg.mask = mask; + inarg.action = action; + inarg.group = (uint64_t)group; + + args.opcode = FUSE_FSNOTIFY; + args.nodeid = get_node_id(inode); + args.in_numargs = 1; + args.in_args[0].size = sizeof(struct fuse_notify_fsnotify_in); + args.in_args[0].value = &inarg; + args.out_numargs = 0; + args.force = true; + + err = fuse_simple_request(fm, &args); + + return err; +} +EXPORT_SYMBOL(fuse_fsnotify_send_request); + /* Look up request on processing list by unique ID */ static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique) { diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index c3cebfb936d2..5c83c4535608 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -1243,6 +1243,9 @@ struct posix_acl *fuse_get_acl(struct inode *inode, int type, bool rcu); int fuse_set_acl(struct user_namespace *mnt_userns, struct inode *inode, struct posix_acl *acl, int type); +int fuse_fsnotify_send_request(struct inode *inode, uint32_t mask, + uint32_t action, uint64_t group); + /* readdir.c */ int fuse_readdir(struct file *file, struct dir_context *ctx); -- 2.33.0 _______________________________________________ Virtio-fs mailing list [email protected] https://listman.redhat.com/mailman/listinfo/virtio-fs
