Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 222 insertions, 0 deletions

diff --git a/drivers/dma/idxd/submit.c b/drivers/dma/idxd/submit.c
new file mode 100644
index 000000000..03217041b
--- /dev/null
+++ b/drivers/dma/idxd/submit.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2019 Intel Corporation. All rights rsvd. */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <uapi/linux/idxd.h>
+#include "idxd.h"
+#include "registers.h"
+
+static struct idxd_desc *__get_desc(struct idxd_wq *wq, int idx, int cpu)
+{
+	struct idxd_desc *desc;
+	struct idxd_device *idxd = wq->idxd;
+
+	desc = wq->descs[idx];
+	memset(desc->hw, 0, sizeof(struct dsa_hw_desc));
+	memset(desc->completion, 0, idxd->data->compl_size);
+	desc->cpu = cpu;
+
+	if (device_pasid_enabled(idxd))
+		desc->hw->pasid = idxd->pasid;
+
+	return desc;
+}
+
+struct idxd_desc *idxd_alloc_desc(struct idxd_wq *wq, enum idxd_op_type optype)
+{
+	int cpu, idx;
+	struct idxd_device *idxd = wq->idxd;
+	DEFINE_SBQ_WAIT(wait);
+	struct sbq_wait_state *ws;
+	struct sbitmap_queue *sbq;
+
+	if (idxd->state != IDXD_DEV_ENABLED)
+		return ERR_PTR(-EIO);
+
+	sbq = &wq->sbq;
+	idx = sbitmap_queue_get(sbq, &cpu);
+	if (idx < 0) {
+		if (optype == IDXD_OP_NONBLOCK)
+			return ERR_PTR(-EAGAIN);
+	} else {
+		return __get_desc(wq, idx, cpu);
+	}
+
+	ws = &sbq->ws[0];
+	for (;;) {
+		sbitmap_prepare_to_wait(sbq, ws, &wait, TASK_INTERRUPTIBLE);
+		if (signal_pending_state(TASK_INTERRUPTIBLE, current))
+			break;
+		idx = sbitmap_queue_get(sbq, &cpu);
+		if (idx >= 0)
+			break;
+		schedule();
+	}
+
+	sbitmap_finish_wait(sbq, ws, &wait);
+	if (idx < 0)
+		return ERR_PTR(-EAGAIN);
+
+	return __get_desc(wq, idx, cpu);
+}
+EXPORT_SYMBOL_NS_GPL(idxd_alloc_desc, "IDXD");
+
+void idxd_free_desc(struct idxd_wq *wq, struct idxd_desc *desc)
+{
+	int cpu = desc->cpu;
+
+	desc->cpu = -1;
+	sbitmap_queue_clear(&wq->sbq, desc->id, cpu);
+}
+EXPORT_SYMBOL_NS_GPL(idxd_free_desc, "IDXD");
+
+static struct idxd_desc *list_abort_desc(struct idxd_wq *wq, struct idxd_irq_entry *ie,
+					 struct idxd_desc *desc)
+{
+	struct idxd_desc *d, *n;
+
+	lockdep_assert_held(&ie->list_lock);
+	list_for_each_entry_safe(d, n, &ie->work_list, list) {
+		if (d == desc) {
+			list_del(&d->list);
+			return d;
+		}
+	}
+
+	/*
+	 * At this point, the desc needs to be aborted is held by the completion
+	 * handler where it has taken it off the pending list but has not added to the
+	 * work list. It will be cleaned up by the interrupt handler when it sees the
+	 * IDXD_COMP_DESC_ABORT for completion status.
+	 */
+	return NULL;
+}
+
+static void llist_abort_desc(struct idxd_wq *wq, struct idxd_irq_entry *ie,
+			     struct idxd_desc *desc)
+{
+	struct idxd_desc *d, *t, *found = NULL;
+	struct llist_node *head;
+	LIST_HEAD(flist);
+
+	desc->completion->status = IDXD_COMP_DESC_ABORT;
+	/*
+	 * Grab the list lock so it will block the irq thread handler. This allows the
+	 * abort code to locate the descriptor need to be aborted.
+	 */
+	spin_lock(&ie->list_lock);
+	head = llist_del_all(&ie->pending_llist);
+	if (head) {
+		llist_for_each_entry_safe(d, t, head, llnode) {
+			if (d == desc) {
+				found = desc;
+				continue;
+			}
+
+			if (d->completion->status)
+				list_add_tail(&d->list, &flist);
+			else
+				list_add_tail(&d->list, &ie->work_list);
+		}
+	}
+
+	if (!found)
+		found = list_abort_desc(wq, ie, desc);
+	spin_unlock(&ie->list_lock);
+
+	if (found)
+		idxd_dma_complete_txd(found, IDXD_COMPLETE_ABORT, false,
+				      NULL, NULL);
+
+	/*
+	 * completing the descriptor will return desc to allocator and
+	 * the desc can be acquired by a different process and the
+	 * desc->list can be modified.  Delete desc from list so the
+	 * list traversing does not get corrupted by the other process.
+	 */
+	list_for_each_entry_safe(d, t, &flist, list) {
+		list_del_init(&d->list);
+		idxd_dma_complete_txd(d, IDXD_COMPLETE_ABORT, true,
+				      NULL, NULL);
+	}
+}
+
+/*
+ * ENQCMDS typically fail when the WQ is inactive or busy. On host submission, the driver
+ * has better control of number of descriptors being submitted to a shared wq by limiting
+ * the number of driver allocated descriptors to the wq size. However, when the swq is
+ * exported to a guest kernel, it may be shared with multiple guest kernels. This means
+ * the likelihood of getting busy returned on the swq when submitting goes significantly up.
+ * Having a tunable retry mechanism allows the driver to keep trying for a bit before giving
+ * up. The sysfs knob can be tuned by the system administrator.
+ */
+int idxd_enqcmds(struct idxd_wq *wq, void __iomem *portal, const void *desc)
+{
+	unsigned int retries = wq->enqcmds_retries;
+	int rc;
+
+	do {
+		rc = enqcmds(portal, desc);
+		if (rc == 0)
+			break;
+		cpu_relax();
+	} while (retries--);
+
+	return rc;
+}
+
+int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
+{
+	struct idxd_device *idxd = wq->idxd;
+	struct idxd_irq_entry *ie = NULL;
+	u32 desc_flags = desc->hw->flags;
+	void __iomem *portal;
+	int rc;
+
+	if (idxd->state != IDXD_DEV_ENABLED)
+		return -EIO;
+
+	if (!percpu_ref_tryget_live(&wq->wq_active)) {
+		wait_for_completion(&wq->wq_resurrect);
+		if (!percpu_ref_tryget_live(&wq->wq_active))
+			return -ENXIO;
+	}
+
+	portal = idxd_wq_portal_addr(wq);
+
+	/*
+	 * Pending the descriptor to the lockless list for the irq_entry
+	 * that we designated the descriptor to.
+	 */
+	if (desc_flags & IDXD_OP_FLAG_RCI) {
+		ie = &wq->ie;
+		desc->hw->int_handle = ie->int_handle;
+		llist_add(&desc->llnode, &ie->pending_llist);
+	}
+
+	/*
+	 * The wmb() flushes writes to coherent DMA data before
+	 * possibly triggering a DMA read. The wmb() is necessary
+	 * even on UP because the recipient is a device.
+	 */
+	wmb();
+
+	if (wq_dedicated(wq)) {
+		iosubmit_cmds512(portal, desc->hw, 1);
+	} else {
+		rc = idxd_enqcmds(wq, portal, desc->hw);
+		if (rc < 0) {
+			percpu_ref_put(&wq->wq_active);
+			/* abort operation frees the descriptor */
+			if (ie)
+				llist_abort_desc(wq, ie, desc);
+			return rc;
+		}
+	}
+
+	percpu_ref_put(&wq->wq_active);
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(idxd_submit_desc, "IDXD");