We dotn need two interfaces that only diuffer in whether they return a pointer or NULL vs an semiidentical interface that returns 0 or <0
All uses of _async() for scsi tasks should be replaced with the equivalent _task() function instead
These functions are also async functions for SCSI commands but they return
a task structure or NULL.
This task structure can be used in task management functions to abort the task or a whole task set.
The following used to fail:
./configure --prefix=/tmp/libiscsi
make install
This was because DESTDIR was unconditionally used in Makefile.in.
Instead, use the prefix from ./configure unless overriden by DESTDIR
and/or LIBDIR.
Note that this commit drops ldconfig from the Makefile but I'm not sure
this is wanted outside of packaging anyway.
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
between them makes compilers complain about aliasing.
Merge the two and use one single structure bot both iscsi and scsi sync
commands so that gcc stops crying about strict-aliasing
ld_iscsi.so is a small LD_PRELOAD hack that can be used to make normal
unix utilities such as 'stat' and 'cat' become iSCSI 'aware' and fake
handling an iSCSI URL as a normal read-only file.
See README for examples.
are in flight at the moment.
Aside from commands, we also consider the "has not yet connected completely" as being an i/o.
When this command returns 0 it means we are connected ant the iscsi connection is idle, with no commands in flight.
KVM needs a function to detect idleness like this for its block layer io_flush
function.
"random" ISID randomly.
Dont assume that users will never create multiple contexts
concurrently, in which case the previous getpid()^time(NULL)
would create duplicates.
iscsi-dd can be used to copy the content of one iscsi lun onto a different
iscsi lun of the exact same sixe.
This example illustrates how to "steal" a task structure from a callback
so we can use store it and have it remains valid after the read10 callback
has completed.
It also illustrates the async api of libiscsi for read10/write10.
Initially a number of read10 calls are made asynchronously until the
queue is full.
As each read10 completes and returns data, we issue a write10 to write
that data to the other lun.
As soon as a write10 completes, we "release" the initial read10 task corresponding to what we wrote and issue a new read10 to continue copying the next set of un-read data.
Using the async api, it should be easy to get very high performance and
throughput even from one single thread.
LBA is uint32_t for read/write10
Also store the lba/numblocks arguments in the task structure for read10/write10
This makes it much easier to implement a fully async "read lots/write lots"
applications.
