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Diffstat (limited to 'drivers/infiniband/hw/hfi1/user_exp_rcv.c')
-rw-r--r--drivers/infiniband/hw/hfi1/user_exp_rcv.c1050
1 files changed, 1050 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/user_exp_rcv.c b/drivers/infiniband/hw/hfi1/user_exp_rcv.c
new file mode 100644
index 000000000000..1b640a35b3fe
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/user_exp_rcv.c
@@ -0,0 +1,1050 @@
+/*
+ * Copyright(c) 2015, 2016 Intel Corporation.
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  - Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  - Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  - Neither the name of Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+#include <asm/page.h>
+
+#include "user_exp_rcv.h"
+#include "trace.h"
+#include "mmu_rb.h"
+
+struct tid_group {
+	struct list_head list;
+	unsigned base;
+	u8 size;
+	u8 used;
+	u8 map;
+};
+
+struct tid_rb_node {
+	struct mmu_rb_node mmu;
+	unsigned long phys;
+	struct tid_group *grp;
+	u32 rcventry;
+	dma_addr_t dma_addr;
+	bool freed;
+	unsigned npages;
+	struct page *pages[0];
+};
+
+struct tid_pageset {
+	u16 idx;
+	u16 count;
+};
+
+#define EXP_TID_SET_EMPTY(set) (set.count == 0 && list_empty(&set.list))
+
+#define num_user_pages(vaddr, len)				       \
+	(1 + (((((unsigned long)(vaddr) +			       \
+		 (unsigned long)(len) - 1) & PAGE_MASK) -	       \
+	       ((unsigned long)vaddr & PAGE_MASK)) >> PAGE_SHIFT))
+
+static void unlock_exp_tids(struct hfi1_ctxtdata *, struct exp_tid_set *,
+			    struct rb_root *);
+static u32 find_phys_blocks(struct page **, unsigned, struct tid_pageset *);
+static int set_rcvarray_entry(struct file *, unsigned long, u32,
+			      struct tid_group *, struct page **, unsigned);
+static int mmu_rb_insert(struct rb_root *, struct mmu_rb_node *);
+static void mmu_rb_remove(struct rb_root *, struct mmu_rb_node *,
+			  struct mm_struct *);
+static int mmu_rb_invalidate(struct rb_root *, struct mmu_rb_node *);
+static int program_rcvarray(struct file *, unsigned long, struct tid_group *,
+			    struct tid_pageset *, unsigned, u16, struct page **,
+			    u32 *, unsigned *, unsigned *);
+static int unprogram_rcvarray(struct file *, u32, struct tid_group **);
+static void clear_tid_node(struct hfi1_filedata *, u16, struct tid_rb_node *);
+
+static struct mmu_rb_ops tid_rb_ops = {
+	.insert = mmu_rb_insert,
+	.remove = mmu_rb_remove,
+	.invalidate = mmu_rb_invalidate
+};
+
+static inline u32 rcventry2tidinfo(u32 rcventry)
+{
+	u32 pair = rcventry & ~0x1;
+
+	return EXP_TID_SET(IDX, pair >> 1) |
+		EXP_TID_SET(CTRL, 1 << (rcventry - pair));
+}
+
+static inline void exp_tid_group_init(struct exp_tid_set *set)
+{
+	INIT_LIST_HEAD(&set->list);
+	set->count = 0;
+}
+
+static inline void tid_group_remove(struct tid_group *grp,
+				    struct exp_tid_set *set)
+{
+	list_del_init(&grp->list);
+	set->count--;
+}
+
+static inline void tid_group_add_tail(struct tid_group *grp,
+				      struct exp_tid_set *set)
+{
+	list_add_tail(&grp->list, &set->list);
+	set->count++;
+}
+
+static inline struct tid_group *tid_group_pop(struct exp_tid_set *set)
+{
+	struct tid_group *grp =
+		list_first_entry(&set->list, struct tid_group, list);
+	list_del_init(&grp->list);
+	set->count--;
+	return grp;
+}
+
+static inline void tid_group_move(struct tid_group *group,
+				  struct exp_tid_set *s1,
+				  struct exp_tid_set *s2)
+{
+	tid_group_remove(group, s1);
+	tid_group_add_tail(group, s2);
+}
+
+/*
+ * Initialize context and file private data needed for Expected
+ * receive caching. This needs to be done after the context has
+ * been configured with the eager/expected RcvEntry counts.
+ */
+int hfi1_user_exp_rcv_init(struct file *fp)
+{
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct hfi1_devdata *dd = uctxt->dd;
+	unsigned tidbase;
+	int i, ret = 0;
+
+	spin_lock_init(&fd->tid_lock);
+	spin_lock_init(&fd->invalid_lock);
+	fd->tid_rb_root = RB_ROOT;
+
+	if (!uctxt->subctxt_cnt || !fd->subctxt) {
+		exp_tid_group_init(&uctxt->tid_group_list);
+		exp_tid_group_init(&uctxt->tid_used_list);
+		exp_tid_group_init(&uctxt->tid_full_list);
+
+		tidbase = uctxt->expected_base;
+		for (i = 0; i < uctxt->expected_count /
+			     dd->rcv_entries.group_size; i++) {
+			struct tid_group *grp;
+
+			grp = kzalloc(sizeof(*grp), GFP_KERNEL);
+			if (!grp) {
+				/*
+				 * If we fail here, the groups already
+				 * allocated will be freed by the close
+				 * call.
+				 */
+				ret = -ENOMEM;
+				goto done;
+			}
+			grp->size = dd->rcv_entries.group_size;
+			grp->base = tidbase;
+			tid_group_add_tail(grp, &uctxt->tid_group_list);
+			tidbase += dd->rcv_entries.group_size;
+		}
+	}
+
+	fd->entry_to_rb = kcalloc(uctxt->expected_count,
+				     sizeof(struct rb_node *),
+				     GFP_KERNEL);
+	if (!fd->entry_to_rb)
+		return -ENOMEM;
+
+	if (!HFI1_CAP_IS_USET(TID_UNMAP)) {
+		fd->invalid_tid_idx = 0;
+		fd->invalid_tids = kzalloc(uctxt->expected_count *
+					   sizeof(u32), GFP_KERNEL);
+		if (!fd->invalid_tids) {
+			ret = -ENOMEM;
+			goto done;
+		}
+
+		/*
+		 * Register MMU notifier callbacks. If the registration
+		 * fails, continue but turn off the TID caching for
+		 * all user contexts.
+		 */
+		ret = hfi1_mmu_rb_register(&fd->tid_rb_root, &tid_rb_ops);
+		if (ret) {
+			dd_dev_info(dd,
+				    "Failed MMU notifier registration %d\n",
+				    ret);
+			HFI1_CAP_USET(TID_UNMAP);
+			ret = 0;
+		}
+	}
+
+	/*
+	 * PSM does not have a good way to separate, count, and
+	 * effectively enforce a limit on RcvArray entries used by
+	 * subctxts (when context sharing is used) when TID caching
+	 * is enabled. To help with that, we calculate a per-process
+	 * RcvArray entry share and enforce that.
+	 * If TID caching is not in use, PSM deals with usage on its
+	 * own. In that case, we allow any subctxt to take all of the
+	 * entries.
+	 *
+	 * Make sure that we set the tid counts only after successful
+	 * init.
+	 */
+	spin_lock(&fd->tid_lock);
+	if (uctxt->subctxt_cnt && !HFI1_CAP_IS_USET(TID_UNMAP)) {
+		u16 remainder;
+
+		fd->tid_limit = uctxt->expected_count / uctxt->subctxt_cnt;
+		remainder = uctxt->expected_count % uctxt->subctxt_cnt;
+		if (remainder && fd->subctxt < remainder)
+			fd->tid_limit++;
+	} else {
+		fd->tid_limit = uctxt->expected_count;
+	}
+	spin_unlock(&fd->tid_lock);
+done:
+	return ret;
+}
+
+int hfi1_user_exp_rcv_free(struct hfi1_filedata *fd)
+{
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct tid_group *grp, *gptr;
+
+	if (!test_bit(HFI1_CTXT_SETUP_DONE, &uctxt->event_flags))
+		return 0;
+	/*
+	 * The notifier would have been removed when the process'es mm
+	 * was freed.
+	 */
+	if (!HFI1_CAP_IS_USET(TID_UNMAP))
+		hfi1_mmu_rb_unregister(&fd->tid_rb_root);
+
+	kfree(fd->invalid_tids);
+
+	if (!uctxt->cnt) {
+		if (!EXP_TID_SET_EMPTY(uctxt->tid_full_list))
+			unlock_exp_tids(uctxt, &uctxt->tid_full_list,
+					&fd->tid_rb_root);
+		if (!EXP_TID_SET_EMPTY(uctxt->tid_used_list))
+			unlock_exp_tids(uctxt, &uctxt->tid_used_list,
+					&fd->tid_rb_root);
+		list_for_each_entry_safe(grp, gptr, &uctxt->tid_group_list.list,
+					 list) {
+			list_del_init(&grp->list);
+			kfree(grp);
+		}
+		hfi1_clear_tids(uctxt);
+	}
+
+	kfree(fd->entry_to_rb);
+	return 0;
+}
+
+/*
+ * Write an "empty" RcvArray entry.
+ * This function exists so the TID registaration code can use it
+ * to write to unused/unneeded entries and still take advantage
+ * of the WC performance improvements. The HFI will ignore this
+ * write to the RcvArray entry.
+ */
+static inline void rcv_array_wc_fill(struct hfi1_devdata *dd, u32 index)
+{
+	/*
+	 * Doing the WC fill writes only makes sense if the device is
+	 * present and the RcvArray has been mapped as WC memory.
+	 */
+	if ((dd->flags & HFI1_PRESENT) && dd->rcvarray_wc)
+		writeq(0, dd->rcvarray_wc + (index * 8));
+}
+
+/*
+ * RcvArray entry allocation for Expected Receives is done by the
+ * following algorithm:
+ *
+ * The context keeps 3 lists of groups of RcvArray entries:
+ *   1. List of empty groups - tid_group_list
+ *      This list is created during user context creation and
+ *      contains elements which describe sets (of 8) of empty
+ *      RcvArray entries.
+ *   2. List of partially used groups - tid_used_list
+ *      This list contains sets of RcvArray entries which are
+ *      not completely used up. Another mapping request could
+ *      use some of all of the remaining entries.
+ *   3. List of full groups - tid_full_list
+ *      This is the list where sets that are completely used
+ *      up go.
+ *
+ * An attempt to optimize the usage of RcvArray entries is
+ * made by finding all sets of physically contiguous pages in a
+ * user's buffer.
+ * These physically contiguous sets are further split into
+ * sizes supported by the receive engine of the HFI. The
+ * resulting sets of pages are stored in struct tid_pageset,
+ * which describes the sets as:
+ *    * .count - number of pages in this set
+ *    * .idx - starting index into struct page ** array
+ *                    of this set
+ *
+ * From this point on, the algorithm deals with the page sets
+ * described above. The number of pagesets is divided by the
+ * RcvArray group size to produce the number of full groups
+ * needed.
+ *
+ * Groups from the 3 lists are manipulated using the following
+ * rules:
+ *   1. For each set of 8 pagesets, a complete group from
+ *      tid_group_list is taken, programmed, and moved to
+ *      the tid_full_list list.
+ *   2. For all remaining pagesets:
+ *      2.1 If the tid_used_list is empty and the tid_group_list
+ *          is empty, stop processing pageset and return only
+ *          what has been programmed up to this point.
+ *      2.2 If the tid_used_list is empty and the tid_group_list
+ *          is not empty, move a group from tid_group_list to
+ *          tid_used_list.
+ *      2.3 For each group is tid_used_group, program as much as
+ *          can fit into the group. If the group becomes fully
+ *          used, move it to tid_full_list.
+ */
+int hfi1_user_exp_rcv_setup(struct file *fp, struct hfi1_tid_info *tinfo)
+{
+	int ret = 0, need_group = 0, pinned;
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct hfi1_devdata *dd = uctxt->dd;
+	unsigned npages, ngroups, pageidx = 0, pageset_count, npagesets,
+		tididx = 0, mapped, mapped_pages = 0;
+	unsigned long vaddr = tinfo->vaddr;
+	struct page **pages = NULL;
+	u32 *tidlist = NULL;
+	struct tid_pageset *pagesets = NULL;
+
+	/* Get the number of pages the user buffer spans */
+	npages = num_user_pages(vaddr, tinfo->length);
+	if (!npages)
+		return -EINVAL;
+
+	if (npages > uctxt->expected_count) {
+		dd_dev_err(dd, "Expected buffer too big\n");
+		return -EINVAL;
+	}
+
+	/* Verify that access is OK for the user buffer */
+	if (!access_ok(VERIFY_WRITE, (void __user *)vaddr,
+		       npages * PAGE_SIZE)) {
+		dd_dev_err(dd, "Fail vaddr %p, %u pages, !access_ok\n",
+			   (void *)vaddr, npages);
+		return -EFAULT;
+	}
+
+	pagesets = kcalloc(uctxt->expected_count, sizeof(*pagesets),
+			   GFP_KERNEL);
+	if (!pagesets)
+		return -ENOMEM;
+
+	/* Allocate the array of struct page pointers needed for pinning */
+	pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
+	if (!pages) {
+		ret = -ENOMEM;
+		goto bail;
+	}
+
+	/*
+	 * Pin all the pages of the user buffer. If we can't pin all the
+	 * pages, accept the amount pinned so far and program only that.
+	 * User space knows how to deal with partially programmed buffers.
+	 */
+	if (!hfi1_can_pin_pages(dd, fd->tid_n_pinned, npages)) {
+		ret = -ENOMEM;
+		goto bail;
+	}
+
+	pinned = hfi1_acquire_user_pages(vaddr, npages, true, pages);
+	if (pinned <= 0) {
+		ret = pinned;
+		goto bail;
+	}
+	fd->tid_n_pinned += npages;
+
+	/* Find sets of physically contiguous pages */
+	npagesets = find_phys_blocks(pages, pinned, pagesets);
+
+	/*
+	 * We don't need to access this under a lock since tid_used is per
+	 * process and the same process cannot be in hfi1_user_exp_rcv_clear()
+	 * and hfi1_user_exp_rcv_setup() at the same time.
+	 */
+	spin_lock(&fd->tid_lock);
+	if (fd->tid_used + npagesets > fd->tid_limit)
+		pageset_count = fd->tid_limit - fd->tid_used;
+	else
+		pageset_count = npagesets;
+	spin_unlock(&fd->tid_lock);
+
+	if (!pageset_count)
+		goto bail;
+
+	ngroups = pageset_count / dd->rcv_entries.group_size;
+	tidlist = kcalloc(pageset_count, sizeof(*tidlist), GFP_KERNEL);
+	if (!tidlist) {
+		ret = -ENOMEM;
+		goto nomem;
+	}
+
+	tididx = 0;
+
+	/*
+	 * From this point on, we are going to be using shared (between master
+	 * and subcontexts) context resources. We need to take the lock.
+	 */
+	mutex_lock(&uctxt->exp_lock);
+	/*
+	 * The first step is to program the RcvArray entries which are complete
+	 * groups.
+	 */
+	while (ngroups && uctxt->tid_group_list.count) {
+		struct tid_group *grp =
+			tid_group_pop(&uctxt->tid_group_list);
+
+		ret = program_rcvarray(fp, vaddr, grp, pagesets,
+				       pageidx, dd->rcv_entries.group_size,
+				       pages, tidlist, &tididx, &mapped);
+		/*
+		 * If there was a failure to program the RcvArray
+		 * entries for the entire group, reset the grp fields
+		 * and add the grp back to the free group list.
+		 */
+		if (ret <= 0) {
+			tid_group_add_tail(grp, &uctxt->tid_group_list);
+			hfi1_cdbg(TID,
+				  "Failed to program RcvArray group %d", ret);
+			goto unlock;
+		}
+
+		tid_group_add_tail(grp, &uctxt->tid_full_list);
+		ngroups--;
+		pageidx += ret;
+		mapped_pages += mapped;
+	}
+
+	while (pageidx < pageset_count) {
+		struct tid_group *grp, *ptr;
+		/*
+		 * If we don't have any partially used tid groups, check
+		 * if we have empty groups. If so, take one from there and
+		 * put in the partially used list.
+		 */
+		if (!uctxt->tid_used_list.count || need_group) {
+			if (!uctxt->tid_group_list.count)
+				goto unlock;
+
+			grp = tid_group_pop(&uctxt->tid_group_list);
+			tid_group_add_tail(grp, &uctxt->tid_used_list);
+			need_group = 0;
+		}
+		/*
+		 * There is an optimization opportunity here - instead of
+		 * fitting as many page sets as we can, check for a group
+		 * later on in the list that could fit all of them.
+		 */
+		list_for_each_entry_safe(grp, ptr, &uctxt->tid_used_list.list,
+					 list) {
+			unsigned use = min_t(unsigned, pageset_count - pageidx,
+					     grp->size - grp->used);
+
+			ret = program_rcvarray(fp, vaddr, grp, pagesets,
+					       pageidx, use, pages, tidlist,
+					       &tididx, &mapped);
+			if (ret < 0) {
+				hfi1_cdbg(TID,
+					  "Failed to program RcvArray entries %d",
+					  ret);
+				ret = -EFAULT;
+				goto unlock;
+			} else if (ret > 0) {
+				if (grp->used == grp->size)
+					tid_group_move(grp,
+						       &uctxt->tid_used_list,
+						       &uctxt->tid_full_list);
+				pageidx += ret;
+				mapped_pages += mapped;
+				need_group = 0;
+				/* Check if we are done so we break out early */
+				if (pageidx >= pageset_count)
+					break;
+			} else if (WARN_ON(ret == 0)) {
+				/*
+				 * If ret is 0, we did not program any entries
+				 * into this group, which can only happen if
+				 * we've screwed up the accounting somewhere.
+				 * Warn and try to continue.
+				 */
+				need_group = 1;
+			}
+		}
+	}
+unlock:
+	mutex_unlock(&uctxt->exp_lock);
+nomem:
+	hfi1_cdbg(TID, "total mapped: tidpairs:%u pages:%u (%d)", tididx,
+		  mapped_pages, ret);
+	if (tididx) {
+		spin_lock(&fd->tid_lock);
+		fd->tid_used += tididx;
+		spin_unlock(&fd->tid_lock);
+		tinfo->tidcnt = tididx;
+		tinfo->length = mapped_pages * PAGE_SIZE;
+
+		if (copy_to_user((void __user *)(unsigned long)tinfo->tidlist,
+				 tidlist, sizeof(tidlist[0]) * tididx)) {
+			/*
+			 * On failure to copy to the user level, we need to undo
+			 * everything done so far so we don't leak resources.
+			 */
+			tinfo->tidlist = (unsigned long)&tidlist;
+			hfi1_user_exp_rcv_clear(fp, tinfo);
+			tinfo->tidlist = 0;
+			ret = -EFAULT;
+			goto bail;
+		}
+	}
+
+	/*
+	 * If not everything was mapped (due to insufficient RcvArray entries,
+	 * for example), unpin all unmapped pages so we can pin them nex time.
+	 */
+	if (mapped_pages != pinned) {
+		hfi1_release_user_pages(current->mm, &pages[mapped_pages],
+					pinned - mapped_pages,
+					false);
+		fd->tid_n_pinned -= pinned - mapped_pages;
+	}
+bail:
+	kfree(pagesets);
+	kfree(pages);
+	kfree(tidlist);
+	return ret > 0 ? 0 : ret;
+}
+
+int hfi1_user_exp_rcv_clear(struct file *fp, struct hfi1_tid_info *tinfo)
+{
+	int ret = 0;
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	u32 *tidinfo;
+	unsigned tididx;
+
+	tidinfo = kcalloc(tinfo->tidcnt, sizeof(*tidinfo), GFP_KERNEL);
+	if (!tidinfo)
+		return -ENOMEM;
+
+	if (copy_from_user(tidinfo, (void __user *)(unsigned long)
+			   tinfo->tidlist, sizeof(tidinfo[0]) *
+			   tinfo->tidcnt)) {
+		ret = -EFAULT;
+		goto done;
+	}
+
+	mutex_lock(&uctxt->exp_lock);
+	for (tididx = 0; tididx < tinfo->tidcnt; tididx++) {
+		ret = unprogram_rcvarray(fp, tidinfo[tididx], NULL);
+		if (ret) {
+			hfi1_cdbg(TID, "Failed to unprogram rcv array %d",
+				  ret);
+			break;
+		}
+	}
+	spin_lock(&fd->tid_lock);
+	fd->tid_used -= tididx;
+	spin_unlock(&fd->tid_lock);
+	tinfo->tidcnt = tididx;
+	mutex_unlock(&uctxt->exp_lock);
+done:
+	kfree(tidinfo);
+	return ret;
+}
+
+int hfi1_user_exp_rcv_invalid(struct file *fp, struct hfi1_tid_info *tinfo)
+{
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	unsigned long *ev = uctxt->dd->events +
+		(((uctxt->ctxt - uctxt->dd->first_user_ctxt) *
+		  HFI1_MAX_SHARED_CTXTS) + fd->subctxt);
+	u32 *array;
+	int ret = 0;
+
+	if (!fd->invalid_tids)
+		return -EINVAL;
+
+	/*
+	 * copy_to_user() can sleep, which will leave the invalid_lock
+	 * locked and cause the MMU notifier to be blocked on the lock
+	 * for a long time.
+	 * Copy the data to a local buffer so we can release the lock.
+	 */
+	array = kcalloc(uctxt->expected_count, sizeof(*array), GFP_KERNEL);
+	if (!array)
+		return -EFAULT;
+
+	spin_lock(&fd->invalid_lock);
+	if (fd->invalid_tid_idx) {
+		memcpy(array, fd->invalid_tids, sizeof(*array) *
+		       fd->invalid_tid_idx);
+		memset(fd->invalid_tids, 0, sizeof(*fd->invalid_tids) *
+		       fd->invalid_tid_idx);
+		tinfo->tidcnt = fd->invalid_tid_idx;
+		fd->invalid_tid_idx = 0;
+		/*
+		 * Reset the user flag while still holding the lock.
+		 * Otherwise, PSM can miss events.
+		 */
+		clear_bit(_HFI1_EVENT_TID_MMU_NOTIFY_BIT, ev);
+	} else {
+		tinfo->tidcnt = 0;
+	}
+	spin_unlock(&fd->invalid_lock);
+
+	if (tinfo->tidcnt) {
+		if (copy_to_user((void __user *)tinfo->tidlist,
+				 array, sizeof(*array) * tinfo->tidcnt))
+			ret = -EFAULT;
+	}
+	kfree(array);
+
+	return ret;
+}
+
+static u32 find_phys_blocks(struct page **pages, unsigned npages,
+			    struct tid_pageset *list)
+{
+	unsigned pagecount, pageidx, setcount = 0, i;
+	unsigned long pfn, this_pfn;
+
+	if (!npages)
+		return 0;
+
+	/*
+	 * Look for sets of physically contiguous pages in the user buffer.
+	 * This will allow us to optimize Expected RcvArray entry usage by
+	 * using the bigger supported sizes.
+	 */
+	pfn = page_to_pfn(pages[0]);
+	for (pageidx = 0, pagecount = 1, i = 1; i <= npages; i++) {
+		this_pfn = i < npages ? page_to_pfn(pages[i]) : 0;
+
+		/*
+		 * If the pfn's are not sequential, pages are not physically
+		 * contiguous.
+		 */
+		if (this_pfn != ++pfn) {
+			/*
+			 * At this point we have to loop over the set of
+			 * physically contiguous pages and break them down it
+			 * sizes supported by the HW.
+			 * There are two main constraints:
+			 *     1. The max buffer size is MAX_EXPECTED_BUFFER.
+			 *        If the total set size is bigger than that
+			 *        program only a MAX_EXPECTED_BUFFER chunk.
+			 *     2. The buffer size has to be a power of two. If
+			 *        it is not, round down to the closes power of
+			 *        2 and program that size.
+			 */
+			while (pagecount) {
+				int maxpages = pagecount;
+				u32 bufsize = pagecount * PAGE_SIZE;
+
+				if (bufsize > MAX_EXPECTED_BUFFER)
+					maxpages =
+						MAX_EXPECTED_BUFFER >>
+						PAGE_SHIFT;
+				else if (!is_power_of_2(bufsize))
+					maxpages =
+						rounddown_pow_of_two(bufsize) >>
+						PAGE_SHIFT;
+
+				list[setcount].idx = pageidx;
+				list[setcount].count = maxpages;
+				pagecount -= maxpages;
+				pageidx += maxpages;
+				setcount++;
+			}
+			pageidx = i;
+			pagecount = 1;
+			pfn = this_pfn;
+		} else {
+			pagecount++;
+		}
+	}
+	return setcount;
+}
+
+/**
+ * program_rcvarray() - program an RcvArray group with receive buffers
+ * @fp: file pointer
+ * @vaddr: starting user virtual address
+ * @grp: RcvArray group
+ * @sets: array of struct tid_pageset holding information on physically
+ *        contiguous chunks from the user buffer
+ * @start: starting index into sets array
+ * @count: number of struct tid_pageset's to program
+ * @pages: an array of struct page * for the user buffer
+ * @tidlist: the array of u32 elements when the information about the
+ *           programmed RcvArray entries is to be encoded.
+ * @tididx: starting offset into tidlist
+ * @pmapped: (output parameter) number of pages programmed into the RcvArray
+ *           entries.
+ *
+ * This function will program up to 'count' number of RcvArray entries from the
+ * group 'grp'. To make best use of write-combining writes, the function will
+ * perform writes to the unused RcvArray entries which will be ignored by the
+ * HW. Each RcvArray entry will be programmed with a physically contiguous
+ * buffer chunk from the user's virtual buffer.
+ *
+ * Return:
+ * -EINVAL if the requested count is larger than the size of the group,
+ * -ENOMEM or -EFAULT on error from set_rcvarray_entry(), or
+ * number of RcvArray entries programmed.
+ */
+static int program_rcvarray(struct file *fp, unsigned long vaddr,
+			    struct tid_group *grp,
+			    struct tid_pageset *sets,
+			    unsigned start, u16 count, struct page **pages,
+			    u32 *tidlist, unsigned *tididx, unsigned *pmapped)
+{
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct hfi1_devdata *dd = uctxt->dd;
+	u16 idx;
+	u32 tidinfo = 0, rcventry, useidx = 0;
+	int mapped = 0;
+
+	/* Count should never be larger than the group size */
+	if (count > grp->size)
+		return -EINVAL;
+
+	/* Find the first unused entry in the group */
+	for (idx = 0; idx < grp->size; idx++) {
+		if (!(grp->map & (1 << idx))) {
+			useidx = idx;
+			break;
+		}
+		rcv_array_wc_fill(dd, grp->base + idx);
+	}
+
+	idx = 0;
+	while (idx < count) {
+		u16 npages, pageidx, setidx = start + idx;
+		int ret = 0;
+
+		/*
+		 * If this entry in the group is used, move to the next one.
+		 * If we go past the end of the group, exit the loop.
+		 */
+		if (useidx >= grp->size) {
+			break;
+		} else if (grp->map & (1 << useidx)) {
+			rcv_array_wc_fill(dd, grp->base + useidx);
+			useidx++;
+			continue;
+		}
+
+		rcventry = grp->base + useidx;
+		npages = sets[setidx].count;
+		pageidx = sets[setidx].idx;
+
+		ret = set_rcvarray_entry(fp, vaddr + (pageidx * PAGE_SIZE),
+					 rcventry, grp, pages + pageidx,
+					 npages);
+		if (ret)
+			return ret;
+		mapped += npages;
+
+		tidinfo = rcventry2tidinfo(rcventry - uctxt->expected_base) |
+			EXP_TID_SET(LEN, npages);
+		tidlist[(*tididx)++] = tidinfo;
+		grp->used++;
+		grp->map |= 1 << useidx++;
+		idx++;
+	}
+
+	/* Fill the rest of the group with "blank" writes */
+	for (; useidx < grp->size; useidx++)
+		rcv_array_wc_fill(dd, grp->base + useidx);
+	*pmapped = mapped;
+	return idx;
+}
+
+static int set_rcvarray_entry(struct file *fp, unsigned long vaddr,
+			      u32 rcventry, struct tid_group *grp,
+			      struct page **pages, unsigned npages)
+{
+	int ret;
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct tid_rb_node *node;
+	struct hfi1_devdata *dd = uctxt->dd;
+	struct rb_root *root = &fd->tid_rb_root;
+	dma_addr_t phys;
+
+	/*
+	 * Allocate the node first so we can handle a potential
+	 * failure before we've programmed anything.
+	 */
+	node = kzalloc(sizeof(*node) + (sizeof(struct page *) * npages),
+		       GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+
+	phys = pci_map_single(dd->pcidev,
+			      __va(page_to_phys(pages[0])),
+			      npages * PAGE_SIZE, PCI_DMA_FROMDEVICE);
+	if (dma_mapping_error(&dd->pcidev->dev, phys)) {
+		dd_dev_err(dd, "Failed to DMA map Exp Rcv pages 0x%llx\n",
+			   phys);
+		kfree(node);
+		return -EFAULT;
+	}
+
+	node->mmu.addr = vaddr;
+	node->mmu.len = npages * PAGE_SIZE;
+	node->phys = page_to_phys(pages[0]);
+	node->npages = npages;
+	node->rcventry = rcventry;
+	node->dma_addr = phys;
+	node->grp = grp;
+	node->freed = false;
+	memcpy(node->pages, pages, sizeof(struct page *) * npages);
+
+	if (HFI1_CAP_IS_USET(TID_UNMAP))
+		ret = mmu_rb_insert(root, &node->mmu);
+	else
+		ret = hfi1_mmu_rb_insert(root, &node->mmu);
+
+	if (ret) {
+		hfi1_cdbg(TID, "Failed to insert RB node %u 0x%lx, 0x%lx %d",
+			  node->rcventry, node->mmu.addr, node->phys, ret);
+		pci_unmap_single(dd->pcidev, phys, npages * PAGE_SIZE,
+				 PCI_DMA_FROMDEVICE);
+		kfree(node);
+		return -EFAULT;
+	}
+	hfi1_put_tid(dd, rcventry, PT_EXPECTED, phys, ilog2(npages) + 1);
+	trace_hfi1_exp_tid_reg(uctxt->ctxt, fd->subctxt, rcventry, npages,
+			       node->mmu.addr, node->phys, phys);
+	return 0;
+}
+
+static int unprogram_rcvarray(struct file *fp, u32 tidinfo,
+			      struct tid_group **grp)
+{
+	struct hfi1_filedata *fd = fp->private_data;
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct hfi1_devdata *dd = uctxt->dd;
+	struct tid_rb_node *node;
+	u8 tidctrl = EXP_TID_GET(tidinfo, CTRL);
+	u32 tididx = EXP_TID_GET(tidinfo, IDX) << 1, rcventry;
+
+	if (tididx >= uctxt->expected_count) {
+		dd_dev_err(dd, "Invalid RcvArray entry (%u) index for ctxt %u\n",
+			   tididx, uctxt->ctxt);
+		return -EINVAL;
+	}
+
+	if (tidctrl == 0x3)
+		return -EINVAL;
+
+	rcventry = tididx + (tidctrl - 1);
+
+	node = fd->entry_to_rb[rcventry];
+	if (!node || node->rcventry != (uctxt->expected_base + rcventry))
+		return -EBADF;
+	if (HFI1_CAP_IS_USET(TID_UNMAP))
+		mmu_rb_remove(&fd->tid_rb_root, &node->mmu, NULL);
+	else
+		hfi1_mmu_rb_remove(&fd->tid_rb_root, &node->mmu);
+
+	if (grp)
+		*grp = node->grp;
+	clear_tid_node(fd, fd->subctxt, node);
+	return 0;
+}
+
+static void clear_tid_node(struct hfi1_filedata *fd, u16 subctxt,
+			   struct tid_rb_node *node)
+{
+	struct hfi1_ctxtdata *uctxt = fd->uctxt;
+	struct hfi1_devdata *dd = uctxt->dd;
+
+	trace_hfi1_exp_tid_unreg(uctxt->ctxt, fd->subctxt, node->rcventry,
+				 node->npages, node->mmu.addr, node->phys,
+				 node->dma_addr);
+
+	hfi1_put_tid(dd, node->rcventry, PT_INVALID, 0, 0);
+	/*
+	 * Make sure device has seen the write before we unpin the
+	 * pages.
+	 */
+	flush_wc();
+
+	pci_unmap_single(dd->pcidev, node->dma_addr, node->mmu.len,
+			 PCI_DMA_FROMDEVICE);
+	hfi1_release_user_pages(current->mm, node->pages, node->npages, true);
+	fd->tid_n_pinned -= node->npages;
+
+	node->grp->used--;
+	node->grp->map &= ~(1 << (node->rcventry - node->grp->base));
+
+	if (node->grp->used == node->grp->size - 1)
+		tid_group_move(node->grp, &uctxt->tid_full_list,
+			       &uctxt->tid_used_list);
+	else if (!node->grp->used)
+		tid_group_move(node->grp, &uctxt->tid_used_list,
+			       &uctxt->tid_group_list);
+	kfree(node);
+}
+
+static void unlock_exp_tids(struct hfi1_ctxtdata *uctxt,
+			    struct exp_tid_set *set, struct rb_root *root)
+{
+	struct tid_group *grp, *ptr;
+	struct hfi1_filedata *fd = container_of(root, struct hfi1_filedata,
+						tid_rb_root);
+	int i;
+
+	list_for_each_entry_safe(grp, ptr, &set->list, list) {
+		list_del_init(&grp->list);
+
+		for (i = 0; i < grp->size; i++) {
+			if (grp->map & (1 << i)) {
+				u16 rcventry = grp->base + i;
+				struct tid_rb_node *node;
+
+				node = fd->entry_to_rb[rcventry -
+							  uctxt->expected_base];
+				if (!node || node->rcventry != rcventry)
+					continue;
+				if (HFI1_CAP_IS_USET(TID_UNMAP))
+					mmu_rb_remove(&fd->tid_rb_root,
+						      &node->mmu, NULL);
+				else
+					hfi1_mmu_rb_remove(&fd->tid_rb_root,
+							   &node->mmu);
+				clear_tid_node(fd, -1, node);
+			}
+		}
+	}
+}
+
+static int mmu_rb_invalidate(struct rb_root *root, struct mmu_rb_node *mnode)
+{
+	struct hfi1_filedata *fdata =
+		container_of(root, struct hfi1_filedata, tid_rb_root);
+	struct hfi1_ctxtdata *uctxt = fdata->uctxt;
+	struct tid_rb_node *node =
+		container_of(mnode, struct tid_rb_node, mmu);
+
+	if (node->freed)
+		return 0;
+
+	trace_hfi1_exp_tid_inval(uctxt->ctxt, fdata->subctxt, node->mmu.addr,
+				 node->rcventry, node->npages, node->dma_addr);
+	node->freed = true;
+
+	spin_lock(&fdata->invalid_lock);
+	if (fdata->invalid_tid_idx < uctxt->expected_count) {
+		fdata->invalid_tids[fdata->invalid_tid_idx] =
+			rcventry2tidinfo(node->rcventry - uctxt->expected_base);
+		fdata->invalid_tids[fdata->invalid_tid_idx] |=
+			EXP_TID_SET(LEN, node->npages);
+		if (!fdata->invalid_tid_idx) {
+			unsigned long *ev;
+
+			/*
+			 * hfi1_set_uevent_bits() sets a user event flag
+			 * for all processes. Because calling into the
+			 * driver to process TID cache invalidations is
+			 * expensive and TID cache invalidations are
+			 * handled on a per-process basis, we can
+			 * optimize this to set the flag only for the
+			 * process in question.
+			 */
+			ev = uctxt->dd->events +
+				(((uctxt->ctxt - uctxt->dd->first_user_ctxt) *
+				  HFI1_MAX_SHARED_CTXTS) + fdata->subctxt);
+			set_bit(_HFI1_EVENT_TID_MMU_NOTIFY_BIT, ev);
+		}
+		fdata->invalid_tid_idx++;
+	}
+	spin_unlock(&fdata->invalid_lock);
+	return 0;
+}
+
+static int mmu_rb_insert(struct rb_root *root, struct mmu_rb_node *node)
+{
+	struct hfi1_filedata *fdata =
+		container_of(root, struct hfi1_filedata, tid_rb_root);
+	struct tid_rb_node *tnode =
+		container_of(node, struct tid_rb_node, mmu);
+	u32 base = fdata->uctxt->expected_base;
+
+	fdata->entry_to_rb[tnode->rcventry - base] = tnode;
+	return 0;
+}
+
+static void mmu_rb_remove(struct rb_root *root, struct mmu_rb_node *node,
+			  struct mm_struct *mm)
+{
+	struct hfi1_filedata *fdata =
+		container_of(root, struct hfi1_filedata, tid_rb_root);
+	struct tid_rb_node *tnode =
+		container_of(node, struct tid_rb_node, mmu);
+	u32 base = fdata->uctxt->expected_base;
+
+	fdata->entry_to_rb[tnode->rcventry - base] = NULL;
+}