[PATCH for-next 9/9] IB/hfi1: Refactor reset_ctxt() IOCTL

Dennis Dalessandro
2017-09-26T14:04:42Z

The IOCTL is a bit unwieldy. Refactor reset_ctxt() to be a bit more
manageable.

Reviewed-by: Ira Weiny <ira.weiny-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/hw/hfi1/file_ops.c | 122 ++++++++++++++++++---------------
1 files changed, 66 insertions(+), 56 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/file_ops.c b/drivers/infiniband/hw/hfi1/file_ops.c
index 6497b65..22feca5 100644
--- a/drivers/infiniband/hw/hfi1/file_ops.c
+++ b/drivers/infiniband/hw/hfi1/file_ops.c
@@ -107,6 +107,7 @@ static int allocate_ctxt(struct hfi1_filedata *fd, struct hfi1_devdata *dd,
static int user_event_ack(struct hfi1_ctxtdata *uctxt, u16 subctxt,
unsigned long arg);
static int set_ctxt_pkey(struct hfi1_ctxtdata *uctxt, unsigned long arg);
+static int ctxt_reset(struct hfi1_ctxtdata *uctxt);
static int manage_rcvq(struct hfi1_ctxtdata *uctxt, u16 subctxt,
unsigned long arg);
static int vma_fault(struct vm_fault *vmf);
@@ -282,63 +283,9 @@ static long hfi1_file_ioctl(struct file *fp, unsigned int cmd,
ret = set_ctxt_pkey(uctxt, arg);
break;

- case HFI1_IOCTL_CTXT_RESET: {
- struct send_context *sc;
- struct hfi1_devdata *dd;
-
- if (!uctxt || !uctxt->dd || !uctxt->sc)
- return -EINVAL;
-
- /*
- * There is no protection here. User level has to
- * guarantee that no one will be writing to the send
- * context while it is being re-initialized.
- * If user level breaks that guarantee, it will break
- * it's own context and no one else's.
- */
- dd = uctxt->dd;
- sc = uctxt->sc;
- /*
- * Wait until the interrupt handler has marked the
- * context as halted or frozen. Report error if we time
- * out.
- */
- wait_event_interruptible_timeout(
- sc->halt_wait, (sc->flags & SCF_HALTED),
- msecs_to_jiffies(SEND_CTXT_HALT_TIMEOUT));
- if (!(sc->flags & SCF_HALTED))
- return -ENOLCK;
-
- /*
- * If the send context was halted due to a Freeze,
- * wait until the device has been "unfrozen" before
- * resetting the context.
- */
- if (sc->flags & SCF_FROZEN) {
- wait_event_interruptible_timeout(
- dd->event_queue,
- !(ACCESS_ONCE(dd->flags) & HFI1_FROZEN),
- msecs_to_jiffies(SEND_CTXT_HALT_TIMEOUT));
- if (dd->flags & HFI1_FROZEN)
- return -ENOLCK;
-
- if (dd->flags & HFI1_FORCED_FREEZE)
- /*
- * Don't allow context reset if we are into
- * forced freeze
- */
- return -ENODEV;
-
- sc_disable(sc);
- ret = sc_enable(sc);
- hfi1_rcvctrl(dd, HFI1_RCVCTRL_CTXT_ENB, uctxt);
- } else {
- ret = sc_restart(sc);
- }
- if (!ret)
- sc_return_credits(sc);
+ case HFI1_IOCTL_CTXT_RESET:
+ ret = ctxt_reset(uctxt);
break;
- }

case HFI1_IOCTL_GET_VERS:
uval = HFI1_USER_SWVERSION;
@@ -1658,6 +1605,69 @@ static int set_ctxt_pkey(struct hfi1_ctxtdata *uctxt, unsigned long arg)
return -ENOENT;
}

+/**
+ * ctxt_reset - Reset the user context
+ * @uctxt: valid user context
+ */
+static int ctxt_reset(struct hfi1_ctxtdata *uctxt)
+{
+ struct send_context *sc;
+ struct hfi1_devdata *dd;
+ int ret = 0;
+
+ if (!uctxt || !uctxt->dd || !uctxt->sc)
+ return -EINVAL;
+
+ /*
+ * There is no protection here. User level has to guarantee that
+ * no one will be writing to the send context while it is being
+ * re-initialized. If user level breaks that guarantee, it will
+ * break it's own context and no one else's.
+ */
+ dd = uctxt->dd;
+ sc = uctxt->sc;
+
+ /*
+ * Wait until the interrupt handler has marked the context as
+ * halted or frozen. Report error if we time out.
+ */
+ wait_event_interruptible_timeout(
+ sc->halt_wait, (sc->flags & SCF_HALTED),
+ msecs_to_jiffies(SEND_CTXT_HALT_TIMEOUT));
+ if (!(sc->flags & SCF_HALTED))
+ return -ENOLCK;
+
+ /*
+ * If the send context was halted due to a Freeze, wait until the
+ * device has been "unfrozen" before resetting the context.
+ */
+ if (sc->flags & SCF_FROZEN) {
+ wait_event_interruptible_timeout(
+ dd->event_queue,
+ !(READ_ONCE(dd->flags) & HFI1_FROZEN),
+ msecs_to_jiffies(SEND_CTXT_HALT_TIMEOUT));
+ if (dd->flags & HFI1_FROZEN)
+ return -ENOLCK;
+
+ if (dd->flags & HFI1_FORCED_FREEZE)
+ /*
+ * Don't allow context reset if we are into
+ * forced freeze
+ */
+ return -ENODEV;
+
+ sc_disable(sc);
+ ret = sc_enable(sc);
+ hfi1_rcvctrl(dd, HFI1_RCVCTRL_CTXT_ENB, uctxt);
+ } else {
+ ret = sc_restart(sc);
+ }
+ if (!ret)
+ sc_return_credits(sc);
+
+ return ret;
+}
+
static void user_remove(struct hfi1_devdata *dd)