If the login phase takes multiple login requests we should keep the ITT the same for all login requets and not increment it.
A multi-phase login is only a single task eventhough it may be spread across multiple login requetst.
While most targets are forgiving and still work if we increment the ITT for each login command, some targets such as SOLARIS/COMSTAR is NOT forgiving if we break the protocol in this situation.
Fix the ITT handling so that we dont make SOLARIS/COMSTAR upset.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Set only the (socket) options which are defined on a given platform.
The function becomes a no-op if no option is known at complie time.
Remove autoconf test for HAVE_TCP_KEEPALIVE too.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
no data to read from the socket and there is no error.
For this case, if FIONREAD tells us that there are 0 bytes to read, check if
there is a socket error and return ok/error based on that.
Some eventsystems may cause this to burn some cpu if the socket is ok
but there are no bytes available to read by invoking POLLIN over and over, but it is better than failing the application.
for a read10 call, the application might have specified too few buffers
for the full I/O.
For example if the application tries to read just 512 bytes off a MMC device.
In this case we wopuld run out of buffers and fail with a SEGV.
Instead of failing like this, return NULL from the function to locate a suitable buffer and read the remaining data from the command into the callback buffer instead, just like when no read-buffer at all has been specified.
It is not real zero-copy since the data is still copied in the kernel,
but it avoids copying the data inside libiscsi as well as in the callback.
For SCSI tasks that will return data from the target, the application can now
specify application buffers for libiscsi to read the data directly into.
This is done by calling scsi_task_add_data_in_buffer(task, ...
These buffers need not be linear, you can specify different areas to read into
by calling this function several times.
See examples/iscsiclient.c for an example.
