mmc: core: check for zero length ioctl data
authorJohan Rudholm <johan.rudholm@stericsson.com>
Wed, 23 Nov 2011 08:05:58 +0000 (09:05 +0100)
committerChris Ball <cjb@laptop.org>
Thu, 12 Jan 2012 04:58:42 +0000 (23:58 -0500)
commit4d6144de8ba263eb3691a737c547e5b2fdc45287
tree18ff9af5efcf42fdafae2e76a0df75cf498923e8
parent4ee5ebaf74ba1b3e2e3f9aad442bf38db96c20d2
mmc: core: check for zero length ioctl data

If the read or write buffer size associated with the command sent
through the mmc_blk_ioctl is zero, do not prepare data buffer.

This enables a ioctl(2) call to for instance send a MMC_SWITCH to set
a byte in the ext_csd.

Signed-off-by: Johan Rudholm <johan.rudholm@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
drivers/mmc/card/block.c