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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.c972
1 files changed, 972 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 000000000..350884d5f
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/user_exp_rcv.c
@@ -0,0 +1,972 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+/*
+ * Copyright(c) 2020 Cornelis Networks, Inc.
+ * Copyright(c) 2015-2018 Intel Corporation.
+ */
+#include <asm/page.h>
+#include <linux/string.h>
+
+#include "mmu_rb.h"
+#include "user_exp_rcv.h"
+#include "trace.h"
+
+static void unlock_exp_tids(struct hfi1_ctxtdata *uctxt,
+ struct exp_tid_set *set,
+ struct hfi1_filedata *fd);
+static u32 find_phys_blocks(struct tid_user_buf *tidbuf, unsigned int npages);
+static int set_rcvarray_entry(struct hfi1_filedata *fd,
+ struct tid_user_buf *tbuf,
+ u32 rcventry, struct tid_group *grp,
+ u16 pageidx, unsigned int npages);
+static void cacheless_tid_rb_remove(struct hfi1_filedata *fdata,
+ struct tid_rb_node *tnode);
+static bool tid_rb_invalidate(struct mmu_interval_notifier *mni,
+ const struct mmu_notifier_range *range,
+ unsigned long cur_seq);
+static bool tid_cover_invalidate(struct mmu_interval_notifier *mni,
+ const struct mmu_notifier_range *range,
+ unsigned long cur_seq);
+static int program_rcvarray(struct hfi1_filedata *fd, struct tid_user_buf *,
+ struct tid_group *grp,
+ unsigned int start, u16 count,
+ u32 *tidlist, unsigned int *tididx,
+ unsigned int *pmapped);
+static int unprogram_rcvarray(struct hfi1_filedata *fd, u32 tidinfo);
+static void __clear_tid_node(struct hfi1_filedata *fd,
+ struct tid_rb_node *node);
+static void clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node);
+
+static const struct mmu_interval_notifier_ops tid_mn_ops = {
+ .invalidate = tid_rb_invalidate,
+};
+static const struct mmu_interval_notifier_ops tid_cover_ops = {
+ .invalidate = tid_cover_invalidate,
+};
+
+/*
+ * 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 hfi1_filedata *fd,
+ struct hfi1_ctxtdata *uctxt)
+{
+ int ret = 0;
+
+ fd->entry_to_rb = kcalloc(uctxt->expected_count,
+ sizeof(struct rb_node *),
+ GFP_KERNEL);
+ if (!fd->entry_to_rb)
+ return -ENOMEM;
+
+ if (!HFI1_CAP_UGET_MASK(uctxt->flags, TID_UNMAP)) {
+ fd->invalid_tid_idx = 0;
+ fd->invalid_tids = kcalloc(uctxt->expected_count,
+ sizeof(*fd->invalid_tids),
+ GFP_KERNEL);
+ if (!fd->invalid_tids) {
+ kfree(fd->entry_to_rb);
+ fd->entry_to_rb = NULL;
+ return -ENOMEM;
+ }
+ fd->use_mn = true;
+ }
+
+ /*
+ * 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 && fd->use_mn) {
+ 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);
+
+ return ret;
+}
+
+void hfi1_user_exp_rcv_free(struct hfi1_filedata *fd)
+{
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+
+ mutex_lock(&uctxt->exp_mutex);
+ if (!EXP_TID_SET_EMPTY(uctxt->tid_full_list))
+ unlock_exp_tids(uctxt, &uctxt->tid_full_list, fd);
+ if (!EXP_TID_SET_EMPTY(uctxt->tid_used_list))
+ unlock_exp_tids(uctxt, &uctxt->tid_used_list, fd);
+ mutex_unlock(&uctxt->exp_mutex);
+
+ kfree(fd->invalid_tids);
+ fd->invalid_tids = NULL;
+
+ kfree(fd->entry_to_rb);
+ fd->entry_to_rb = NULL;
+}
+
+/*
+ * Release pinned receive buffer pages.
+ *
+ * @mapped: true if the pages have been DMA mapped. false otherwise.
+ * @idx: Index of the first page to unpin.
+ * @npages: No of pages to unpin.
+ *
+ * If the pages have been DMA mapped (indicated by mapped parameter), their
+ * info will be passed via a struct tid_rb_node. If they haven't been mapped,
+ * their info will be passed via a struct tid_user_buf.
+ */
+static void unpin_rcv_pages(struct hfi1_filedata *fd,
+ struct tid_user_buf *tidbuf,
+ struct tid_rb_node *node,
+ unsigned int idx,
+ unsigned int npages,
+ bool mapped)
+{
+ struct page **pages;
+ struct hfi1_devdata *dd = fd->uctxt->dd;
+ struct mm_struct *mm;
+
+ if (mapped) {
+ dma_unmap_single(&dd->pcidev->dev, node->dma_addr,
+ node->npages * PAGE_SIZE, DMA_FROM_DEVICE);
+ pages = &node->pages[idx];
+ mm = mm_from_tid_node(node);
+ } else {
+ pages = &tidbuf->pages[idx];
+ mm = current->mm;
+ }
+ hfi1_release_user_pages(mm, pages, npages, mapped);
+ fd->tid_n_pinned -= npages;
+}
+
+/*
+ * Pin receive buffer pages.
+ */
+static int pin_rcv_pages(struct hfi1_filedata *fd, struct tid_user_buf *tidbuf)
+{
+ int pinned;
+ unsigned int npages = tidbuf->npages;
+ unsigned long vaddr = tidbuf->vaddr;
+ struct page **pages = NULL;
+ struct hfi1_devdata *dd = fd->uctxt->dd;
+
+ if (npages > fd->uctxt->expected_count) {
+ dd_dev_err(dd, "Expected buffer too big\n");
+ return -EINVAL;
+ }
+
+ /* Allocate the array of struct page pointers needed for pinning */
+ pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ /*
+ * 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, current->mm, fd->tid_n_pinned, npages)) {
+ kfree(pages);
+ return -ENOMEM;
+ }
+
+ pinned = hfi1_acquire_user_pages(current->mm, vaddr, npages, true, pages);
+ if (pinned <= 0) {
+ kfree(pages);
+ return pinned;
+ }
+ tidbuf->pages = pages;
+ fd->tid_n_pinned += pinned;
+ return pinned;
+}
+
+/*
+ * 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 hfi1_filedata *fd,
+ struct hfi1_tid_info *tinfo)
+{
+ int ret = 0, need_group = 0, pinned;
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+ struct hfi1_devdata *dd = uctxt->dd;
+ unsigned int ngroups, pageidx = 0, pageset_count,
+ tididx = 0, mapped, mapped_pages = 0;
+ u32 *tidlist = NULL;
+ struct tid_user_buf *tidbuf;
+ unsigned long mmu_seq = 0;
+
+ if (!PAGE_ALIGNED(tinfo->vaddr))
+ return -EINVAL;
+ if (tinfo->length == 0)
+ return -EINVAL;
+
+ tidbuf = kzalloc(sizeof(*tidbuf), GFP_KERNEL);
+ if (!tidbuf)
+ return -ENOMEM;
+
+ mutex_init(&tidbuf->cover_mutex);
+ tidbuf->vaddr = tinfo->vaddr;
+ tidbuf->length = tinfo->length;
+ tidbuf->npages = num_user_pages(tidbuf->vaddr, tidbuf->length);
+ tidbuf->psets = kcalloc(uctxt->expected_count, sizeof(*tidbuf->psets),
+ GFP_KERNEL);
+ if (!tidbuf->psets) {
+ ret = -ENOMEM;
+ goto fail_release_mem;
+ }
+
+ if (fd->use_mn) {
+ ret = mmu_interval_notifier_insert(
+ &tidbuf->notifier, current->mm,
+ tidbuf->vaddr, tidbuf->npages * PAGE_SIZE,
+ &tid_cover_ops);
+ if (ret)
+ goto fail_release_mem;
+ mmu_seq = mmu_interval_read_begin(&tidbuf->notifier);
+ }
+
+ pinned = pin_rcv_pages(fd, tidbuf);
+ if (pinned <= 0) {
+ ret = (pinned < 0) ? pinned : -ENOSPC;
+ goto fail_unpin;
+ }
+
+ /* Find sets of physically contiguous pages */
+ tidbuf->n_psets = find_phys_blocks(tidbuf, pinned);
+
+ /* Reserve the number of expected tids to be used. */
+ spin_lock(&fd->tid_lock);
+ if (fd->tid_used + tidbuf->n_psets > fd->tid_limit)
+ pageset_count = fd->tid_limit - fd->tid_used;
+ else
+ pageset_count = tidbuf->n_psets;
+ fd->tid_used += pageset_count;
+ spin_unlock(&fd->tid_lock);
+
+ if (!pageset_count) {
+ ret = -ENOSPC;
+ goto fail_unreserve;
+ }
+
+ ngroups = pageset_count / dd->rcv_entries.group_size;
+ tidlist = kcalloc(pageset_count, sizeof(*tidlist), GFP_KERNEL);
+ if (!tidlist) {
+ ret = -ENOMEM;
+ goto fail_unreserve;
+ }
+
+ 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_mutex);
+ /*
+ * 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(fd, tidbuf, grp,
+ pageidx, dd->rcv_entries.group_size,
+ 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(fd, tidbuf, grp,
+ pageidx, use, tidlist,
+ &tididx, &mapped);
+ if (ret < 0) {
+ hfi1_cdbg(TID,
+ "Failed to program RcvArray entries %d",
+ ret);
+ 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_mutex);
+ hfi1_cdbg(TID, "total mapped: tidpairs:%u pages:%u (%d)", tididx,
+ mapped_pages, ret);
+
+ /* fail if nothing was programmed, set error if none provided */
+ if (tididx == 0) {
+ if (ret >= 0)
+ ret = -ENOSPC;
+ goto fail_unreserve;
+ }
+
+ /* adjust reserved tid_used to actual count */
+ spin_lock(&fd->tid_lock);
+ fd->tid_used -= pageset_count - tididx;
+ spin_unlock(&fd->tid_lock);
+
+ /* unpin all pages not covered by a TID */
+ unpin_rcv_pages(fd, tidbuf, NULL, mapped_pages, pinned - mapped_pages,
+ false);
+
+ if (fd->use_mn) {
+ /* check for an invalidate during setup */
+ bool fail = false;
+
+ mutex_lock(&tidbuf->cover_mutex);
+ fail = mmu_interval_read_retry(&tidbuf->notifier, mmu_seq);
+ mutex_unlock(&tidbuf->cover_mutex);
+
+ if (fail) {
+ ret = -EBUSY;
+ goto fail_unprogram;
+ }
+ }
+
+ tinfo->tidcnt = tididx;
+ tinfo->length = mapped_pages * PAGE_SIZE;
+
+ if (copy_to_user(u64_to_user_ptr(tinfo->tidlist),
+ tidlist, sizeof(tidlist[0]) * tididx)) {
+ ret = -EFAULT;
+ goto fail_unprogram;
+ }
+
+ if (fd->use_mn)
+ mmu_interval_notifier_remove(&tidbuf->notifier);
+ kfree(tidbuf->pages);
+ kfree(tidbuf->psets);
+ kfree(tidbuf);
+ kfree(tidlist);
+ return 0;
+
+fail_unprogram:
+ /* unprogram, unmap, and unpin all allocated TIDs */
+ tinfo->tidlist = (unsigned long)tidlist;
+ hfi1_user_exp_rcv_clear(fd, tinfo);
+ tinfo->tidlist = 0;
+ pinned = 0; /* nothing left to unpin */
+ pageset_count = 0; /* nothing left reserved */
+fail_unreserve:
+ spin_lock(&fd->tid_lock);
+ fd->tid_used -= pageset_count;
+ spin_unlock(&fd->tid_lock);
+fail_unpin:
+ if (fd->use_mn)
+ mmu_interval_notifier_remove(&tidbuf->notifier);
+ if (pinned > 0)
+ unpin_rcv_pages(fd, tidbuf, NULL, 0, pinned, false);
+fail_release_mem:
+ kfree(tidbuf->pages);
+ kfree(tidbuf->psets);
+ kfree(tidbuf);
+ kfree(tidlist);
+ return ret;
+}
+
+int hfi1_user_exp_rcv_clear(struct hfi1_filedata *fd,
+ struct hfi1_tid_info *tinfo)
+{
+ int ret = 0;
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+ u32 *tidinfo;
+ unsigned tididx;
+
+ if (unlikely(tinfo->tidcnt > fd->tid_used))
+ return -EINVAL;
+
+ tidinfo = memdup_user(u64_to_user_ptr(tinfo->tidlist),
+ sizeof(tidinfo[0]) * tinfo->tidcnt);
+ if (IS_ERR(tidinfo))
+ return PTR_ERR(tidinfo);
+
+ mutex_lock(&uctxt->exp_mutex);
+ for (tididx = 0; tididx < tinfo->tidcnt; tididx++) {
+ ret = unprogram_rcvarray(fd, tidinfo[tididx]);
+ 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_mutex);
+
+ kfree(tidinfo);
+ return ret;
+}
+
+int hfi1_user_exp_rcv_invalid(struct hfi1_filedata *fd,
+ struct hfi1_tid_info *tinfo)
+{
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+ unsigned long *ev = uctxt->dd->events +
+ (uctxt_offset(uctxt) + fd->subctxt);
+ u32 *array;
+ int ret = 0;
+
+ /*
+ * 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 tid_user_buf *tidbuf, unsigned int npages)
+{
+ unsigned pagecount, pageidx, setcount = 0, i;
+ unsigned long pfn, this_pfn;
+ struct page **pages = tidbuf->pages;
+ struct tid_pageset *list = tidbuf->psets;
+
+ 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
+ * @fd: filedata pointer
+ * @tbuf: pointer to struct tid_user_buf that has the user buffer starting
+ * virtual address, buffer length, page pointers, pagesets (array of
+ * struct tid_pageset holding information on physically contiguous
+ * chunks from the user buffer), and other fields.
+ * @grp: RcvArray group
+ * @start: starting index into sets array
+ * @count: number of struct tid_pageset's to program
+ * @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 hfi1_filedata *fd, struct tid_user_buf *tbuf,
+ struct tid_group *grp,
+ unsigned int start, u16 count,
+ u32 *tidlist, unsigned int *tididx,
+ unsigned int *pmapped)
+{
+ 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 = tbuf->psets[setidx].count;
+ pageidx = tbuf->psets[setidx].idx;
+
+ ret = set_rcvarray_entry(fd, tbuf,
+ rcventry, grp, 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 hfi1_filedata *fd,
+ struct tid_user_buf *tbuf,
+ u32 rcventry, struct tid_group *grp,
+ u16 pageidx, unsigned int npages)
+{
+ int ret;
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+ struct tid_rb_node *node;
+ struct hfi1_devdata *dd = uctxt->dd;
+ dma_addr_t phys;
+ struct page **pages = tbuf->pages + pageidx;
+
+ /*
+ * Allocate the node first so we can handle a potential
+ * failure before we've programmed anything.
+ */
+ node = kzalloc(struct_size(node, pages, npages), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ phys = dma_map_single(&dd->pcidev->dev, __va(page_to_phys(pages[0])),
+ npages * PAGE_SIZE, DMA_FROM_DEVICE);
+ 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->fdata = fd;
+ mutex_init(&node->invalidate_mutex);
+ 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, flex_array_size(node, pages, npages));
+
+ if (fd->use_mn) {
+ ret = mmu_interval_notifier_insert(
+ &node->notifier, current->mm,
+ tbuf->vaddr + (pageidx * PAGE_SIZE), npages * PAGE_SIZE,
+ &tid_mn_ops);
+ if (ret)
+ goto out_unmap;
+ }
+ fd->entry_to_rb[node->rcventry - uctxt->expected_base] = node;
+
+ hfi1_put_tid(dd, rcventry, PT_EXPECTED, phys, ilog2(npages) + 1);
+ trace_hfi1_exp_tid_reg(uctxt->ctxt, fd->subctxt, rcventry, npages,
+ node->notifier.interval_tree.start, node->phys,
+ phys);
+ return 0;
+
+out_unmap:
+ hfi1_cdbg(TID, "Failed to insert RB node %u 0x%lx, 0x%lx %d",
+ node->rcventry, node->notifier.interval_tree.start,
+ node->phys, ret);
+ dma_unmap_single(&dd->pcidev->dev, phys, npages * PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ kfree(node);
+ return -EFAULT;
+}
+
+static int unprogram_rcvarray(struct hfi1_filedata *fd, u32 tidinfo)
+{
+ 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 (fd->use_mn)
+ mmu_interval_notifier_remove(&node->notifier);
+ cacheless_tid_rb_remove(fd, node);
+
+ return 0;
+}
+
+static void __clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node)
+{
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+ struct hfi1_devdata *dd = uctxt->dd;
+
+ mutex_lock(&node->invalidate_mutex);
+ if (node->freed)
+ goto done;
+ node->freed = true;
+
+ trace_hfi1_exp_tid_unreg(uctxt->ctxt, fd->subctxt, node->rcventry,
+ node->npages,
+ node->notifier.interval_tree.start, node->phys,
+ node->dma_addr);
+
+ /* Make sure device has seen the write before pages are unpinned */
+ hfi1_put_tid(dd, node->rcventry, PT_INVALID_FLUSH, 0, 0);
+
+ unpin_rcv_pages(fd, NULL, node, 0, node->npages, true);
+done:
+ mutex_unlock(&node->invalidate_mutex);
+}
+
+static void clear_tid_node(struct hfi1_filedata *fd, struct tid_rb_node *node)
+{
+ struct hfi1_ctxtdata *uctxt = fd->uctxt;
+
+ __clear_tid_node(fd, node);
+
+ 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);
+}
+
+/*
+ * As a simple helper for hfi1_user_exp_rcv_free, this function deals with
+ * clearing nodes in the non-cached case.
+ */
+static void unlock_exp_tids(struct hfi1_ctxtdata *uctxt,
+ struct exp_tid_set *set,
+ struct hfi1_filedata *fd)
+{
+ struct tid_group *grp, *ptr;
+ 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 (fd->use_mn)
+ mmu_interval_notifier_remove(
+ &node->notifier);
+ cacheless_tid_rb_remove(fd, node);
+ }
+ }
+ }
+}
+
+static bool tid_rb_invalidate(struct mmu_interval_notifier *mni,
+ const struct mmu_notifier_range *range,
+ unsigned long cur_seq)
+{
+ struct tid_rb_node *node =
+ container_of(mni, struct tid_rb_node, notifier);
+ struct hfi1_filedata *fdata = node->fdata;
+ struct hfi1_ctxtdata *uctxt = fdata->uctxt;
+
+ if (node->freed)
+ return true;
+
+ /* take action only if unmapping */
+ if (range->event != MMU_NOTIFY_UNMAP)
+ return true;
+
+ trace_hfi1_exp_tid_inval(uctxt->ctxt, fdata->subctxt,
+ node->notifier.interval_tree.start,
+ node->rcventry, node->npages, node->dma_addr);
+
+ /* clear the hardware rcvarray entry */
+ __clear_tid_node(fdata, node);
+
+ 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_offset(uctxt) + fdata->subctxt);
+ set_bit(_HFI1_EVENT_TID_MMU_NOTIFY_BIT, ev);
+ }
+ fdata->invalid_tid_idx++;
+ }
+ spin_unlock(&fdata->invalid_lock);
+ return true;
+}
+
+static bool tid_cover_invalidate(struct mmu_interval_notifier *mni,
+ const struct mmu_notifier_range *range,
+ unsigned long cur_seq)
+{
+ struct tid_user_buf *tidbuf =
+ container_of(mni, struct tid_user_buf, notifier);
+
+ /* take action only if unmapping */
+ if (range->event == MMU_NOTIFY_UNMAP) {
+ mutex_lock(&tidbuf->cover_mutex);
+ mmu_interval_set_seq(mni, cur_seq);
+ mutex_unlock(&tidbuf->cover_mutex);
+ }
+
+ return true;
+}
+
+static void cacheless_tid_rb_remove(struct hfi1_filedata *fdata,
+ struct tid_rb_node *tnode)
+{
+ u32 base = fdata->uctxt->expected_base;
+
+ fdata->entry_to_rb[tnode->rcventry - base] = NULL;
+ clear_tid_node(fdata, tnode);
+}