target/user: Fix inconsistent kmap_atomic/kunmap_atomic

Pointers that are mapped by kmap_atomic() + offset must
be unmapped without the offset. That would cause problems
if the SG element length exceeds the PAGE_SIZE limit.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Sagi Grimberg 2015-06-11 19:58:34 +03:00 committed by Nicholas Bellinger
parent 7c0d0d51d2
commit e2e21bd8f9

View File

@ -260,7 +260,8 @@ static void alloc_and_scatter_data_area(struct tcmu_dev *udev,
/* Uh oh, we wrapped the buffer. Must split sg across 2 iovs. */ /* Uh oh, we wrapped the buffer. Must split sg across 2 iovs. */
if (sg->length != copy_bytes) { if (sg->length != copy_bytes) {
from += copy_bytes; void *from_skip = from + copy_bytes;
copy_bytes = sg->length - copy_bytes; copy_bytes = sg->length - copy_bytes;
(*iov)->iov_len = copy_bytes; (*iov)->iov_len = copy_bytes;
@ -270,7 +271,7 @@ static void alloc_and_scatter_data_area(struct tcmu_dev *udev,
if (copy_data) { if (copy_data) {
to = (void *) udev->mb_addr + to = (void *) udev->mb_addr +
udev->data_off + udev->data_head; udev->data_off + udev->data_head;
memcpy(to, from, copy_bytes); memcpy(to, from_skip, copy_bytes);
tcmu_flush_dcache_range(to, copy_bytes); tcmu_flush_dcache_range(to, copy_bytes);
} }
@ -281,7 +282,7 @@ static void alloc_and_scatter_data_area(struct tcmu_dev *udev,
copy_bytes, udev->data_size); copy_bytes, udev->data_size);
} }
kunmap_atomic(from); kunmap_atomic(from - sg->offset);
} }
} }
@ -309,18 +310,19 @@ static void gather_and_free_data_area(struct tcmu_dev *udev,
/* Uh oh, wrapped the data buffer for this sg's data */ /* Uh oh, wrapped the data buffer for this sg's data */
if (sg->length != copy_bytes) { if (sg->length != copy_bytes) {
void *to_skip = to + copy_bytes;
from = (void *) udev->mb_addr + from = (void *) udev->mb_addr +
udev->data_off + udev->data_tail; udev->data_off + udev->data_tail;
WARN_ON(udev->data_tail); WARN_ON(udev->data_tail);
to += copy_bytes;
copy_bytes = sg->length - copy_bytes; copy_bytes = sg->length - copy_bytes;
tcmu_flush_dcache_range(from, copy_bytes); tcmu_flush_dcache_range(from, copy_bytes);
memcpy(to, from, copy_bytes); memcpy(to_skip, from, copy_bytes);
UPDATE_HEAD(udev->data_tail, UPDATE_HEAD(udev->data_tail,
copy_bytes, udev->data_size); copy_bytes, udev->data_size);
} }
kunmap_atomic(to); kunmap_atomic(to - sg->offset);
} }
} }