On Sat, 2015-04-11 at 13:17 +0900, Akinobu Mita wrote: > The scatterlist for protection information which is passed to > sbc_dif_verify_read() or sbc_dif_verify_write() requires that > neighboring scatterlist entries are contiguous or chained so that they > can be iterated by sg_next(). > > However, the protection information for RD-MCP backends could be located > in the multiple scatterlist arrays when the ramdisk space is too large. > So if the read/write request straddles this boundary, sbc_dif_verify_read() > or sbc_dif_verify_write() can't iterate all scatterlist entries. > > This problem can be fixed by chaining protection information scatterlist > at creation time. For the architectures which don't support sg chaining > (i.e. !CONFIG_ARCH_HAS_SG_CHAIN), fix it by allocating temporary > scatterlist if needed. > > Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> > Cc: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> > Cc: Sagi Grimberg <sagig@xxxxxxxxxxxxxxxxxx> > Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: "James E.J. Bottomley" <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> > Cc: target-devel@xxxxxxxxxxxxxxx > Cc: linux-scsi@xxxxxxxxxxxxxxx > --- > * v3 > - Fix it by chaining protection information scatterlist at creation time > if CONFIG_ARCH_HAS_SG_CHAIN is defined. > > drivers/target/target_core_rd.c | 67 +++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 64 insertions(+), 3 deletions(-) Applied to target-pending/for-next. Thanks for updating to use CONFIG_ARCH_HAS_SG_CHAIN for the common case. :) --nab -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
