Add a test to verify the pdu timeout handling.
Fix numerous bugs in the timeout handling. It was really broken.
Add test for non-SCSI task PDUs too and verify they works.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Just ignore any iSCSI AsyncMsg / SCSI Async Events we receive instead of
reconnecting. We can't pass the data back to the application anyway
with the current API.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
RFC3720 10.19. NOP-In
NOP-In is either sent by a target as a response to a NOP-Out, as a
"ping" to an initiator, or as a means to carry a changed ExpCmdSN
and/or MaxCmdSN if another PDU will not be available for a long time
(as determined by the target).
...
Signed-off-by: Peter Lieven <pl@kamp.de>
We no longer need to modify pdu->flags directly any more from
iscsi_logout_async_internal. We can just pass these as extra flags to
iscsi_allocate_pdu().
We also always set ISCSI_PDU_DROP_ON_RECONNECT unconditionally so there is
no need to pass this flag in from the callers in pdu.c .
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Remove iscsi_allocate_pdu() which is just a wrapper.
Rename iscsi_allocate_pdu_with_itt_flags() to iscsi_allocate_pdu()
and update all callers.
This only removes a wrapper function and contains no logic changes.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
If we have writes that do not have the Final bit set during reconnect
we must send out any missing data-out PDU.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Dell Equallogic storages may redirect connections from one member of a multi member storage
group to another. When the member that has the volume lead changes the storage issues
an async disconnect request message. The correct behaviour would be to either fail all I/O requests
with a check condition (waiting for logout) or fullfil requests until the time specified
in the disconnect request message has elapsed and then drop the connection. In firwamre 7.x
however the storage sometimes cancels requests with SENSE KEY:ILLEGAL_REQUEST(5)
ASCQ:LOGICAL_UNIT_NOT_SUPPORTED(0x2500). This leads to I/O errors propagated to the application.
This patch was reported in May 2014 to Dell and the initial bug 71409 has been fixed in 7.0.7.
However, the first fix did not entirely solve the problem and bug 73732 has been raised.
This patch adds an environment variable LIBISCSI_DROP_CONN_ON_ASYNC_EVENT1 which if set leads
to an immediate drop of the connection when such an async event is received. This is ugly, but
works around the I/O errors.
Signed-off-by: Peter Lieven <pl@kamp.de>
The outqueue_current PDU might also be in waitpdu if it does not have
ISCSI_PDU_DELETE_WHEN_SENT. outqueue_current is freed after the
waitpdu list (for reconnect or defer_reconnect), or sometimes not
considered at all (for cancel), and this can cause a dangling pointer.
Keep outqueue_current up to date when a PDU is freed. A bit hacky,
but it avoids touching code all over the place.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
if the rejected packet is a NOP-Out it is legal
that it has no callback. In this case we end
up in a segfault.
Signed-off-by: Peter Lieven <pl@kamp.de>
after a target has send the async target requests logout event it may
reject each request with a waiting for logout reason. Catch these
rejects if an outstanding request and the logout event overlap.
Signed-off-by: Peter Lieven <pl@kamp.de>
Rename the macros for managing the linked lists from SLIST_* to ISCSI_LIST_*
to avoid a clash on *BSD which already have other macros SLIST_*
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
The iSCSI protocol adds padding to a data packet if the data size is not
a multiple of four. The iovector provided by QEMU does not include such
padding, and libiscsi then complains that there was a protocol error.
This patch fixes this by reading the padding in a separate "recv"
system call. These packets anyway do not happen in the data path,
where the packet size is a multiple of 512.
This fixes QEMU's scsi-generic backend, which triggered the problem when
the target sent a 66-byte INQUIRY response.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch finally introduces a small allocation pool
which recycles all the small portions of memory that
are used for headers and pdu structures. This was
the initial idea behind wrapping all memory functions
in libiscsi.
The results of booting are test system up to the login
prompt are quite impressive:
BEFORE:
libiscsi:5 memory is clean at iscsi_destroy_context() after 10712 mallocs, 18 realloc(s) and 10712 free(s)
AFTER:
libiscsi:5 memory is clean at iscsi_destroy_context() after 41 mallocs, 18 realloc(s), 41 free(s) and 10584 reused small allocations
Signed-off-by: Peter Lieven <pl@kamp.de>
A storage might sent an R2T response for a WRITE command while
we still sending out the WRITE command PDU. This is especially
the case when the command PDU carries immediata data.
Without this patch the R2T response will get lost as
the cmdpdu for the R2T cannot be found in iscsi_process_pdu()
leading to a deadlock.
Signed-off-by: Peter Lieven <pl@kamp.de>
This patch avoid incrementing itt to 0xffffffff which is
a reserved value for immediate pdus. Avoid incrementing
it to 0xfffffff to avoid unexpected behaviour.
Signed-off-by: Peter Lieven <pl@kamp.de>
RFC3720 says that cmdsn comparison must be done using
serial32 arithmetic. This will definetly avoid a deadlock
if cmdsn wraps from 2^32-1 to 0.
Signed-off-by: Peter Lieven <pl@kamp.de>
We can simply next the iscsi_scsi_cbdata in the iscsi_pdu struct
since it is only used inside the iscsi_pdu.
This saves one malloc for each pdu.
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>
added a few tweaks to further remove the need to memory
allocation resizing by preallocating the right buffer size.
Signed-off-by: Peter Lieven <pl@kamp.de>
This patch adds logarithmic malloc behaviour to iscsi_add_data().
Currently for each new call there is a new buffer allocated
and all old data is copied to the new buffer. Change this by
allocating at least PAGE_SIZE bytes and increase the allocation
by powers of 2 each time it does no longer fit.
