Is it correct to say: "is just this what/all I'll leave behind me?"

I’d need help from English native speakers to check the following phrase:
"A fleeting smile captured on a torn, yellowed snapshot, is just this what/all I’ll leave behind me?" The words "what" or "all" are both ok to me so can be interchangeable.
It should be part of a lyrics so it doesn’t need to be polite or formal, just correct.
Thanks in advance

EDIT:
thanks to Greybeard and Ammu.

Ok, so it seems that the problem is the word "just". My concern, other that without the "just" word, I have a missing syllable regard the original melody, is that I used the word "just" to emphasize the meaning of the phrase. Is "just" a photo what will survive me once I’ll be gone? Does the phrase mantain this meaning without that word and/or is there a way to reprase the whole line in order to keep the meaning and hopefully the number of syllabes? Thanks