The maximum number of blocks that can be transferred at once via a READ6
command is 256 instead of 265.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
The code that verifies the pr_type response must compare only the
lower four bits of byte 21 of the response ("TYPE") and must ignore
the upper four bits ("SCOPE").
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
If no reservation is held a SCSI target sends a response that is eight
bytes long while scsi-lowlevel.c fills in the first twelve bytes of a
data structure for which only eight bytes are allocated. Fix this buffer
overflow by always allocating a full
scsi_persistent_reserve_in_read_reservation structure.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Add a simple test that it works or is not implemented.
Add a RCTD test to verify that with this flag clear we get command descriptors without CTDP set and with it set we get command descriptors with CTDP set and a timeout descriptor
This patch adds support for read/writev to directly read and write
from/to iovectors. Before this patch on read and write from/to socket
the operation was limited by the iovec boundaries. If there is enough
data in the buffer or enough buffer space available its now possible
to transfer the whole data in one atomic operaion.
Signed-off-by: Peter Lieven <pl@kamp.de>
Remove the size field as it is not used. If we would keep it
we would have to calculate it in scsi_task_set_iov_in/out which
would add unneccassry wals to the iovec array.
Signed-off-by: Peter Lieven <pl@kamp.de>
This has the nice side effect to remove the compiler warning
"dereferencing type-punned pointer will break strict-aliasing rules"
which occur since gcc-4.7.
There are 79 locations where the warning occurs. All of them are in
statements where the htonl/htons/ntohl/ntohs functions are used, e.g.:
in lib/pdu.c itt = ntohl(*(uint32_t *)&in->hdr[16]);
in lib/scsi-lowlevel.c *(uint32_t *)&task->cdb[2] = htonl(lba);
The warning is not related to the htonl/htons/ntohl/ntohs functions but
to the casting/dereferencing operation. If the dereferenced variable is
already a pointer, the warning does not not occur, e.g. this one:
in lib/pdu.c itt = ntohl(*(uint32_t *)&in->data[16]);
The warning is caused by the -fstrict-aliasing option. The
-fstrict-aliasing option is enabled at optimization levels -O2, -O3, -Os.
Signed-off-by: Bernhard Kohl <bernhard.kohl@gmx.net>
This patch defines an scsi_iovec struct which is guaranteed
to be POSIX compatible. It furthermore adds support for
in+out iovectors for bi-directional operations
Signed-off-by: Peter Lieven <pl@kamp.de>
If an application passes buffers to libiscsi for reading they are
currently added to a linked list one by one. This leads to a malloc
for each buffer object plus O(n) walks trough the list to add
the buffer to then end of the list. Additionally the buffer read
routine takes up to O(n) iterations to find the right buffer
for a request.
This patch introduces an scsi_iovector struct to pass buffers to
an scsi task. Adding a new buffer is in O(1) and finding the
right buffer to also. Malloc requirements are in O(log(n)).
Additionally the scsi_iovector struct is itended to be binary
compatible to an QEMUIOVector allowing to pass this structure
directly to the library.
Initial tests have been made booting an Ubuntu LTS 12.04.1
Desktop server up to the login prompt. The following observations
have been made with regards to scsi_malloc calls:
original implementation: ~11.500 mallocs
using iovector instead of list: ~ 7.500 mallocs
passing the iovector directly: 0 mallocs
To enable this feature in qemu for testing the following patch might
be used:
diff --git a/block/iscsi.c b/block/iscsi.c
index a6a819d..2809c15 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -390,11 +390,16 @@ iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
return NULL;
}
+#if defined(LIBISCSI_FEATURE_IOVECTOR)
+ assert(sizeof(struct QEMUIOVector) == sizeof(struct scsi_iovector));
+ scsi_iovector_assign(acb->task, (struct scsi_iovector*) acb->qiov);
+#else
for (i = 0; i < acb->qiov->niov; i++) {
scsi_task_add_data_in_buffer(acb->task,
acb->qiov->iov[i].iov_len,
acb->qiov->iov[i].iov_base);
}
+#endif
iscsi_set_events(iscsilun);
---
Signed-off-by: Peter Lieven <pl@kamp.de>
Split the INQUIRY data-in unmarshalling into smaller chunks, fixing some
potential memory leaks along the way.
Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
