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author | Jan Glauber <jang@linux.vnet.ibm.com> | 2011-03-23 10:16:01 +0100 |
---|---|---|
committer | Martin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com> | 2011-03-23 10:15:59 +0100 |
commit | 9a26513eb67ec4b2cb1744834076afad21b68aac (patch) | |
tree | 20062d931215ca303a6f601e32c8d21db73a80ee /drivers/s390/cio | |
parent | [S390] setup: register bss section as resource (diff) | |
download | linux-9a26513eb67ec4b2cb1744834076afad21b68aac.tar.xz linux-9a26513eb67ec4b2cb1744834076afad21b68aac.zip |
[S390] qdio: prevent handling of buffers if count is zero
Exit do_QDIO early if the buffer count is zero to prevent side effects
in the following functions.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio')
-rw-r--r-- | drivers/s390/cio/qdio_main.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c index 5640c89cd9de..479c665e9e7c 100644 --- a/drivers/s390/cio/qdio_main.c +++ b/drivers/s390/cio/qdio_main.c @@ -1508,7 +1508,8 @@ int do_QDIO(struct ccw_device *cdev, unsigned int callflags, if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE) return -EBUSY; - + if (!count) + return 0; if (callflags & QDIO_FLAG_SYNC_INPUT) return handle_inbound(irq_ptr->input_qs[q_nr], callflags, bufnr, count); |