Re: [PATCH] ext4: Add support for SFITRIM, an ioctl for secure FITRIM.
From: Eric Sandeen <hidden>
Date: 2014-06-13 19:57:19
Also in:
linux-fsdevel
On 6/13/14, 2:44 PM, JP Abgrall wrote:
On Fri, Jun 13, 2014 at 7:31 AM, Theodore Ts'o [off-list ref] wrote:
<snip>
quoted
If so, you might be better off either doing per-file encryption, or per-file secure discard.The per-file secure discard seems to be the way to go, as there are only a few places in Android where this needs to be turned on. The current idletime-fstrim would switch from FITRIM to SFITRIM to reduce the leftovers.
Apologies if this is a dumb thing to point out, but... mmc is the only in-kernel driver (aside from xen) which can even set the flags necessary to enable secure discard; and then only if mmc_can_secure_erase_trim() is true, so it depends on the card, I guess. I don't know what device you're running on, but figured it might be worth pointing out that not all hardware even supports this capability. -Eric