IB/qib: Add new qib driver for QLogic PCIe InfiniBand adapters

Add a low-level IB driver for QLogic PCIe adapters.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 2317 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c
new file mode 100644
index 000000000000..a142a9eb5226
--- /dev/null
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -0,0 +1,2317 @@
+/*
+ * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
+ * All rights reserved.
+ * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/pci.h>
+#include <linux/poll.h>
+#include <linux/cdev.h>
+#include <linux/swap.h>
+#include <linux/vmalloc.h>
+#include <linux/highmem.h>
+#include <linux/io.h>
+#include <linux/uio.h>
+#include <linux/jiffies.h>
+#include <asm/pgtable.h>
+#include <linux/delay.h>
+
+#include "qib.h"
+#include "qib_common.h"
+#include "qib_user_sdma.h"
+
+static int qib_open(struct inode *, struct file *);
+static int qib_close(struct inode *, struct file *);
+static ssize_t qib_write(struct file *, const char __user *, size_t, loff_t *);
+static ssize_t qib_aio_write(struct kiocb *, const struct iovec *,
+			     unsigned long, loff_t);
+static unsigned int qib_poll(struct file *, struct poll_table_struct *);
+static int qib_mmapf(struct file *, struct vm_area_struct *);
+
+static const struct file_operations qib_file_ops = {
+	.owner = THIS_MODULE,
+	.write = qib_write,
+	.aio_write = qib_aio_write,
+	.open = qib_open,
+	.release = qib_close,
+	.poll = qib_poll,
+	.mmap = qib_mmapf
+};
+
+/*
+ * Convert kernel virtual addresses to physical addresses so they don't
+ * potentially conflict with the chip addresses used as mmap offsets.
+ * It doesn't really matter what mmap offset we use as long as we can
+ * interpret it correctly.
+ */
+static u64 cvt_kvaddr(void *p)
+{
+	struct page *page;
+	u64 paddr = 0;
+
+	page = vmalloc_to_page(p);
+	if (page)
+		paddr = page_to_pfn(page) << PAGE_SHIFT;
+
+	return paddr;
+}
+
+static int qib_get_base_info(struct file *fp, void __user *ubase,
+			     size_t ubase_size)
+{
+	struct qib_ctxtdata *rcd = ctxt_fp(fp);
+	int ret = 0;
+	struct qib_base_info *kinfo = NULL;
+	struct qib_devdata *dd = rcd->dd;
+	struct qib_pportdata *ppd = rcd->ppd;
+	unsigned subctxt_cnt;
+	int shared, master;
+	size_t sz;
+
+	subctxt_cnt = rcd->subctxt_cnt;
+	if (!subctxt_cnt) {
+		shared = 0;
+		master = 0;
+		subctxt_cnt = 1;
+	} else {
+		shared = 1;
+		master = !subctxt_fp(fp);
+	}
+
+	sz = sizeof(*kinfo);
+	/* If context sharing is not requested, allow the old size structure */
+	if (!shared)
+		sz -= 7 * sizeof(u64);
+	if (ubase_size < sz) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	kinfo = kzalloc(sizeof(*kinfo), GFP_KERNEL);
+	if (kinfo == NULL) {
+		ret = -ENOMEM;
+		goto bail;
+	}
+
+	ret = dd->f_get_base_info(rcd, kinfo);
+	if (ret < 0)
+		goto bail;
+
+	kinfo->spi_rcvhdr_cnt = dd->rcvhdrcnt;
+	kinfo->spi_rcvhdrent_size = dd->rcvhdrentsize;
+	kinfo->spi_tidegrcnt = rcd->rcvegrcnt;
+	kinfo->spi_rcv_egrbufsize = dd->rcvegrbufsize;
+	/*
+	 * have to mmap whole thing
+	 */
+	kinfo->spi_rcv_egrbuftotlen =
+		rcd->rcvegrbuf_chunks * rcd->rcvegrbuf_size;
+	kinfo->spi_rcv_egrperchunk = rcd->rcvegrbufs_perchunk;
+	kinfo->spi_rcv_egrchunksize = kinfo->spi_rcv_egrbuftotlen /
+		rcd->rcvegrbuf_chunks;
+	kinfo->spi_tidcnt = dd->rcvtidcnt / subctxt_cnt;
+	if (master)
+		kinfo->spi_tidcnt += dd->rcvtidcnt % subctxt_cnt;
+	/*
+	 * for this use, may be cfgctxts summed over all chips that
+	 * are are configured and present
+	 */
+	kinfo->spi_nctxts = dd->cfgctxts;
+	/* unit (chip/board) our context is on */
+	kinfo->spi_unit = dd->unit;
+	kinfo->spi_port = ppd->port;
+	/* for now, only a single page */
+	kinfo->spi_tid_maxsize = PAGE_SIZE;
+
+	/*
+	 * Doing this per context, and based on the skip value, etc.  This has
+	 * to be the actual buffer size, since the protocol code treats it
+	 * as an array.
+	 *
+	 * These have to be set to user addresses in the user code via mmap.
+	 * These values are used on return to user code for the mmap target
+	 * addresses only.  For 32 bit, same 44 bit address problem, so use
+	 * the physical address, not virtual.  Before 2.6.11, using the
+	 * page_address() macro worked, but in 2.6.11, even that returns the
+	 * full 64 bit address (upper bits all 1's).  So far, using the
+	 * physical addresses (or chip offsets, for chip mapping) works, but
+	 * no doubt some future kernel release will change that, and we'll be
+	 * on to yet another method of dealing with this.
+	 * Normally only one of rcvhdr_tailaddr or rhf_offset is useful
+	 * since the chips with non-zero rhf_offset don't normally
+	 * enable tail register updates to host memory, but for testing,
+	 * both can be enabled and used.
+	 */
+	kinfo->spi_rcvhdr_base = (u64) rcd->rcvhdrq_phys;
+	kinfo->spi_rcvhdr_tailaddr = (u64) rcd->rcvhdrqtailaddr_phys;
+	kinfo->spi_rhf_offset = dd->rhf_offset;
+	kinfo->spi_rcv_egrbufs = (u64) rcd->rcvegr_phys;
+	kinfo->spi_pioavailaddr = (u64) dd->pioavailregs_phys;
+	/* setup per-unit (not port) status area for user programs */
+	kinfo->spi_status = (u64) kinfo->spi_pioavailaddr +
+		(char *) ppd->statusp -
+		(char *) dd->pioavailregs_dma;
+	kinfo->spi_uregbase = (u64) dd->uregbase + dd->ureg_align * rcd->ctxt;
+	if (!shared) {
+		kinfo->spi_piocnt = rcd->piocnt;
+		kinfo->spi_piobufbase = (u64) rcd->piobufs;
+		kinfo->spi_sendbuf_status = cvt_kvaddr(rcd->user_event_mask);
+	} else if (master) {
+		kinfo->spi_piocnt = (rcd->piocnt / subctxt_cnt) +
+				    (rcd->piocnt % subctxt_cnt);
+		/* Master's PIO buffers are after all the slave's */
+		kinfo->spi_piobufbase = (u64) rcd->piobufs +
+			dd->palign *
+			(rcd->piocnt - kinfo->spi_piocnt);
+	} else {
+		unsigned slave = subctxt_fp(fp) - 1;
+
+		kinfo->spi_piocnt = rcd->piocnt / subctxt_cnt;
+		kinfo->spi_piobufbase = (u64) rcd->piobufs +
+			dd->palign * kinfo->spi_piocnt * slave;
+	}
+
+	if (shared) {
+		kinfo->spi_sendbuf_status =
+			cvt_kvaddr(&rcd->user_event_mask[subctxt_fp(fp)]);
+		/* only spi_subctxt_* fields should be set in this block! */
+		kinfo->spi_subctxt_uregbase = cvt_kvaddr(rcd->subctxt_uregbase);
+
+		kinfo->spi_subctxt_rcvegrbuf =
+			cvt_kvaddr(rcd->subctxt_rcvegrbuf);
+		kinfo->spi_subctxt_rcvhdr_base =
+			cvt_kvaddr(rcd->subctxt_rcvhdr_base);
+	}
+
+	/*
+	 * All user buffers are 2KB buffers.  If we ever support
+	 * giving 4KB buffers to user processes, this will need some
+	 * work.  Can't use piobufbase directly, because it has
+	 * both 2K and 4K buffer base values.
+	 */
+	kinfo->spi_pioindex = (kinfo->spi_piobufbase - dd->pio2k_bufbase) /
+		dd->palign;
+	kinfo->spi_pioalign = dd->palign;
+	kinfo->spi_qpair = QIB_KD_QP;
+	/*
+	 * user mode PIO buffers are always 2KB, even when 4KB can
+	 * be received, and sent via the kernel; this is ibmaxlen
+	 * for 2K MTU.
+	 */
+	kinfo->spi_piosize = dd->piosize2k - 2 * sizeof(u32);
+	kinfo->spi_mtu = ppd->ibmaxlen; /* maxlen, not ibmtu */
+	kinfo->spi_ctxt = rcd->ctxt;
+	kinfo->spi_subctxt = subctxt_fp(fp);
+	kinfo->spi_sw_version = QIB_KERN_SWVERSION;
+	kinfo->spi_sw_version |= 1U << 31; /* QLogic-built, not kernel.org */
+	kinfo->spi_hw_version = dd->revision;
+
+	if (master)
+		kinfo->spi_runtime_flags |= QIB_RUNTIME_MASTER;
+
+	sz = (ubase_size < sizeof(*kinfo)) ? ubase_size : sizeof(*kinfo);
+	if (copy_to_user(ubase, kinfo, sz))
+		ret = -EFAULT;
+bail:
+	kfree(kinfo);
+	return ret;
+}
+
+/**
+ * qib_tid_update - update a context TID
+ * @rcd: the context
+ * @fp: the qib device file
+ * @ti: the TID information
+ *
+ * The new implementation as of Oct 2004 is that the driver assigns
+ * the tid and returns it to the caller.   To reduce search time, we
+ * keep a cursor for each context, walking the shadow tid array to find
+ * one that's not in use.
+ *
+ * For now, if we can't allocate the full list, we fail, although
+ * in the long run, we'll allocate as many as we can, and the
+ * caller will deal with that by trying the remaining pages later.
+ * That means that when we fail, we have to mark the tids as not in
+ * use again, in our shadow copy.
+ *
+ * It's up to the caller to free the tids when they are done.
+ * We'll unlock the pages as they free them.
+ *
+ * Also, right now we are locking one page at a time, but since
+ * the intended use of this routine is for a single group of
+ * virtually contiguous pages, that should change to improve
+ * performance.
+ */
+static int qib_tid_update(struct qib_ctxtdata *rcd, struct file *fp,
+			  const struct qib_tid_info *ti)
+{
+	int ret = 0, ntids;
+	u32 tid, ctxttid, cnt, i, tidcnt, tidoff;
+	u16 *tidlist;
+	struct qib_devdata *dd = rcd->dd;
+	u64 physaddr;
+	unsigned long vaddr;
+	u64 __iomem *tidbase;
+	unsigned long tidmap[8];
+	struct page **pagep = NULL;
+	unsigned subctxt = subctxt_fp(fp);
+
+	if (!dd->pageshadow) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	cnt = ti->tidcnt;
+	if (!cnt) {
+		ret = -EFAULT;
+		goto done;
+	}
+	ctxttid = rcd->ctxt * dd->rcvtidcnt;
+	if (!rcd->subctxt_cnt) {
+		tidcnt = dd->rcvtidcnt;
+		tid = rcd->tidcursor;
+		tidoff = 0;
+	} else if (!subctxt) {
+		tidcnt = (dd->rcvtidcnt / rcd->subctxt_cnt) +
+			 (dd->rcvtidcnt % rcd->subctxt_cnt);
+		tidoff = dd->rcvtidcnt - tidcnt;
+		ctxttid += tidoff;
+		tid = tidcursor_fp(fp);
+	} else {
+		tidcnt = dd->rcvtidcnt / rcd->subctxt_cnt;
+		tidoff = tidcnt * (subctxt - 1);
+		ctxttid += tidoff;
+		tid = tidcursor_fp(fp);
+	}
+	if (cnt > tidcnt) {
+		/* make sure it all fits in tid_pg_list */
+		qib_devinfo(dd->pcidev, "Process tried to allocate %u "
+			 "TIDs, only trying max (%u)\n", cnt, tidcnt);
+		cnt = tidcnt;
+	}
+	pagep = (struct page **) rcd->tid_pg_list;
+	tidlist = (u16 *) &pagep[dd->rcvtidcnt];
+	pagep += tidoff;
+	tidlist += tidoff;
+
+	memset(tidmap, 0, sizeof(tidmap));
+	/* before decrement; chip actual # */
+	ntids = tidcnt;
+	tidbase = (u64 __iomem *) (((char __iomem *) dd->kregbase) +
+				   dd->rcvtidbase +
+				   ctxttid * sizeof(*tidbase));
+
+	/* virtual address of first page in transfer */
+	vaddr = ti->tidvaddr;
+	if (!access_ok(VERIFY_WRITE, (void __user *) vaddr,
+		       cnt * PAGE_SIZE)) {
+		ret = -EFAULT;
+		goto done;
+	}
+	ret = qib_get_user_pages(vaddr, cnt, pagep);
+	if (ret) {
+		/*
+		 * if (ret == -EBUSY)
+		 * We can't continue because the pagep array won't be
+		 * initialized. This should never happen,
+		 * unless perhaps the user has mpin'ed the pages
+		 * themselves.
+		 */
+		qib_devinfo(dd->pcidev,
+			 "Failed to lock addr %p, %u pages: "
+			 "errno %d\n", (void *) vaddr, cnt, -ret);
+		goto done;
+	}
+	for (i = 0; i < cnt; i++, vaddr += PAGE_SIZE) {
+		for (; ntids--; tid++) {
+			if (tid == tidcnt)
+				tid = 0;
+			if (!dd->pageshadow[ctxttid + tid])
+				break;
+		}
+		if (ntids < 0) {
+			/*
+			 * Oops, wrapped all the way through their TIDs,
+			 * and didn't have enough free; see comments at
+			 * start of routine
+			 */
+			i--;    /* last tidlist[i] not filled in */
+			ret = -ENOMEM;
+			break;
+		}
+		tidlist[i] = tid + tidoff;
+		/* we "know" system pages and TID pages are same size */
+		dd->pageshadow[ctxttid + tid] = pagep[i];
+		dd->physshadow[ctxttid + tid] =
+			qib_map_page(dd->pcidev, pagep[i], 0, PAGE_SIZE,
+				     PCI_DMA_FROMDEVICE);
+		/*
+		 * don't need atomic or it's overhead
+		 */
+		__set_bit(tid, tidmap);
+		physaddr = dd->physshadow[ctxttid + tid];
+		/* PERFORMANCE: below should almost certainly be cached */
+		dd->f_put_tid(dd, &tidbase[tid],
+				  RCVHQ_RCV_TYPE_EXPECTED, physaddr);
+		/*
+		 * don't check this tid in qib_ctxtshadow, since we
+		 * just filled it in; start with the next one.
+		 */
+		tid++;
+	}
+
+	if (ret) {
+		u32 limit;
+cleanup:
+		/* jump here if copy out of updated info failed... */
+		/* same code that's in qib_free_tid() */
+		limit = sizeof(tidmap) * BITS_PER_BYTE;
+		if (limit > tidcnt)
+			/* just in case size changes in future */
+			limit = tidcnt;
+		tid = find_first_bit((const unsigned long *)tidmap, limit);
+		for (; tid < limit; tid++) {
+			if (!test_bit(tid, tidmap))
+				continue;
+			if (dd->pageshadow[ctxttid + tid]) {
+				dma_addr_t phys;
+
+				phys = dd->physshadow[ctxttid + tid];
+				dd->physshadow[ctxttid + tid] = dd->tidinvalid;
+				/* PERFORMANCE: below should almost certainly
+				 * be cached
+				 */
+				dd->f_put_tid(dd, &tidbase[tid],
+					      RCVHQ_RCV_TYPE_EXPECTED,
+					      dd->tidinvalid);
+				pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
+					       PCI_DMA_FROMDEVICE);
+				dd->pageshadow[ctxttid + tid] = NULL;
+			}
+		}
+		qib_release_user_pages(pagep, cnt);
+	} else {
+		/*
+		 * Copy the updated array, with qib_tid's filled in, back
+		 * to user.  Since we did the copy in already, this "should
+		 * never fail" If it does, we have to clean up...
+		 */
+		if (copy_to_user((void __user *)
+				 (unsigned long) ti->tidlist,
+				 tidlist, cnt * sizeof(*tidlist))) {
+			ret = -EFAULT;
+			goto cleanup;
+		}
+		if (copy_to_user((void __user *) (unsigned long) ti->tidmap,
+				 tidmap, sizeof tidmap)) {
+			ret = -EFAULT;
+			goto cleanup;
+		}
+		if (tid == tidcnt)
+			tid = 0;
+		if (!rcd->subctxt_cnt)
+			rcd->tidcursor = tid;
+		else
+			tidcursor_fp(fp) = tid;
+	}
+
+done:
+	return ret;
+}
+
+/**
+ * qib_tid_free - free a context TID
+ * @rcd: the context
+ * @subctxt: the subcontext
+ * @ti: the TID info
+ *
+ * right now we are unlocking one page at a time, but since
+ * the intended use of this routine is for a single group of
+ * virtually contiguous pages, that should change to improve
+ * performance.  We check that the TID is in range for this context
+ * but otherwise don't check validity; if user has an error and
+ * frees the wrong tid, it's only their own data that can thereby
+ * be corrupted.  We do check that the TID was in use, for sanity
+ * We always use our idea of the saved address, not the address that
+ * they pass in to us.
+ */
+static int qib_tid_free(struct qib_ctxtdata *rcd, unsigned subctxt,
+			const struct qib_tid_info *ti)
+{
+	int ret = 0;
+	u32 tid, ctxttid, cnt, limit, tidcnt;
+	struct qib_devdata *dd = rcd->dd;
+	u64 __iomem *tidbase;
+	unsigned long tidmap[8];
+
+	if (!dd->pageshadow) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	if (copy_from_user(tidmap, (void __user *)(unsigned long)ti->tidmap,
+			   sizeof tidmap)) {
+		ret = -EFAULT;
+		goto done;
+	}
+
+	ctxttid = rcd->ctxt * dd->rcvtidcnt;
+	if (!rcd->subctxt_cnt)
+		tidcnt = dd->rcvtidcnt;
+	else if (!subctxt) {
+		tidcnt = (dd->rcvtidcnt / rcd->subctxt_cnt) +
+			 (dd->rcvtidcnt % rcd->subctxt_cnt);
+		ctxttid += dd->rcvtidcnt - tidcnt;
+	} else {
+		tidcnt = dd->rcvtidcnt / rcd->subctxt_cnt;
+		ctxttid += tidcnt * (subctxt - 1);
+	}
+	tidbase = (u64 __iomem *) ((char __iomem *)(dd->kregbase) +
+				   dd->rcvtidbase +
+				   ctxttid * sizeof(*tidbase));
+
+	limit = sizeof(tidmap) * BITS_PER_BYTE;
+	if (limit > tidcnt)
+		/* just in case size changes in future */
+		limit = tidcnt;
+	tid = find_first_bit(tidmap, limit);
+	for (cnt = 0; tid < limit; tid++) {
+		/*
+		 * small optimization; if we detect a run of 3 or so without
+		 * any set, use find_first_bit again.  That's mainly to
+		 * accelerate the case where we wrapped, so we have some at
+		 * the beginning, and some at the end, and a big gap
+		 * in the middle.
+		 */
+		if (!test_bit(tid, tidmap))
+			continue;
+		cnt++;
+		if (dd->pageshadow[ctxttid + tid]) {
+			struct page *p;
+			dma_addr_t phys;
+
+			p = dd->pageshadow[ctxttid + tid];
+			dd->pageshadow[ctxttid + tid] = NULL;
+			phys = dd->physshadow[ctxttid + tid];
+			dd->physshadow[ctxttid + tid] = dd->tidinvalid;
+			/* PERFORMANCE: below should almost certainly be
+			 * cached
+			 */
+			dd->f_put_tid(dd, &tidbase[tid],
+				      RCVHQ_RCV_TYPE_EXPECTED, dd->tidinvalid);
+			pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
+				       PCI_DMA_FROMDEVICE);
+			qib_release_user_pages(&p, 1);
+		}
+	}
+done:
+	return ret;
+}
+
+/**
+ * qib_set_part_key - set a partition key
+ * @rcd: the context
+ * @key: the key
+ *
+ * We can have up to 4 active at a time (other than the default, which is
+ * always allowed).  This is somewhat tricky, since multiple contexts may set
+ * the same key, so we reference count them, and clean up at exit.  All 4
+ * partition keys are packed into a single qlogic_ib register.  It's an
+ * error for a process to set the same pkey multiple times.  We provide no
+ * mechanism to de-allocate a pkey at this time, we may eventually need to
+ * do that.  I've used the atomic operations, and no locking, and only make
+ * a single pass through what's available.  This should be more than
+ * adequate for some time. I'll think about spinlocks or the like if and as
+ * it's necessary.
+ */
+static int qib_set_part_key(struct qib_ctxtdata *rcd, u16 key)
+{
+	struct qib_pportdata *ppd = rcd->ppd;
+	int i, any = 0, pidx = -1;
+	u16 lkey = key & 0x7FFF;
+	int ret;
+
+	if (lkey == (QIB_DEFAULT_P_KEY & 0x7FFF)) {
+		/* nothing to do; this key always valid */
+		ret = 0;
+		goto bail;
+	}
+
+	if (!lkey) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	/*
+	 * Set the full membership bit, because it has to be
+	 * set in the register or the packet, and it seems
+	 * cleaner to set in the register than to force all
+	 * callers to set it.
+	 */
+	key |= 0x8000;
+
+	for (i = 0; i < ARRAY_SIZE(rcd->pkeys); i++) {
+		if (!rcd->pkeys[i] && pidx == -1)
+			pidx = i;
+		if (rcd->pkeys[i] == key) {
+			ret = -EEXIST;
+			goto bail;
+		}
+	}
+	if (pidx == -1) {
+		ret = -EBUSY;
+		goto bail;
+	}
+	for (any = i = 0; i < ARRAY_SIZE(ppd->pkeys); i++) {
+		if (!ppd->pkeys[i]) {
+			any++;
+			continue;
+		}
+		if (ppd->pkeys[i] == key) {
+			atomic_t *pkrefs = &ppd->pkeyrefs[i];
+
+			if (atomic_inc_return(pkrefs) > 1) {
+				rcd->pkeys[pidx] = key;
+				ret = 0;
+				goto bail;
+			} else {
+				/*
+				 * lost race, decrement count, catch below
+				 */
+				atomic_dec(pkrefs);
+				any++;
+			}
+		}
+		if ((ppd->pkeys[i] & 0x7FFF) == lkey) {
+			/*
+			 * It makes no sense to have both the limited and
+			 * full membership PKEY set at the same time since
+			 * the unlimited one will disable the limited one.
+			 */
+			ret = -EEXIST;
+			goto bail;
+		}
+	}
+	if (!any) {
+		ret = -EBUSY;
+		goto bail;
+	}
+	for (any = i = 0; i < ARRAY_SIZE(ppd->pkeys); i++) {
+		if (!ppd->pkeys[i] &&
+		    atomic_inc_return(&ppd->pkeyrefs[i]) == 1) {
+			rcd->pkeys[pidx] = key;
+			ppd->pkeys[i] = key;
+			(void) ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_PKEYS, 0);
+			ret = 0;
+			goto bail;
+		}
+	}
+	ret = -EBUSY;
+
+bail:
+	return ret;
+}
+
+/**
+ * qib_manage_rcvq - manage a context's receive queue
+ * @rcd: the context
+ * @subctxt: the subcontext
+ * @start_stop: action to carry out
+ *
+ * start_stop == 0 disables receive on the context, for use in queue
+ * overflow conditions.  start_stop==1 re-enables, to be used to
+ * re-init the software copy of the head register
+ */
+static int qib_manage_rcvq(struct qib_ctxtdata *rcd, unsigned subctxt,
+			   int start_stop)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned int rcvctrl_op;
+
+	if (subctxt)
+		goto bail;
+	/* atomically clear receive enable ctxt. */
+	if (start_stop) {
+		/*
+		 * On enable, force in-memory copy of the tail register to
+		 * 0, so that protocol code doesn't have to worry about
+		 * whether or not the chip has yet updated the in-memory
+		 * copy or not on return from the system call. The chip
+		 * always resets it's tail register back to 0 on a
+		 * transition from disabled to enabled.
+		 */
+		if (rcd->rcvhdrtail_kvaddr)
+			qib_clear_rcvhdrtail(rcd);
+		rcvctrl_op = QIB_RCVCTRL_CTXT_ENB;
+	} else
+		rcvctrl_op = QIB_RCVCTRL_CTXT_DIS;
+	dd->f_rcvctrl(rcd->ppd, rcvctrl_op, rcd->ctxt);
+	/* always; new head should be equal to new tail; see above */
+bail:
+	return 0;
+}
+
+static void qib_clean_part_key(struct qib_ctxtdata *rcd,
+			       struct qib_devdata *dd)
+{
+	int i, j, pchanged = 0;
+	u64 oldpkey;
+	struct qib_pportdata *ppd = rcd->ppd;
+
+	/* for debugging only */
+	oldpkey = (u64) ppd->pkeys[0] |
+		((u64) ppd->pkeys[1] << 16) |
+		((u64) ppd->pkeys[2] << 32) |
+		((u64) ppd->pkeys[3] << 48);
+
+	for (i = 0; i < ARRAY_SIZE(rcd->pkeys); i++) {
+		if (!rcd->pkeys[i])
+			continue;
+		for (j = 0; j < ARRAY_SIZE(ppd->pkeys); j++) {
+			/* check for match independent of the global bit */
+			if ((ppd->pkeys[j] & 0x7fff) !=
+			    (rcd->pkeys[i] & 0x7fff))
+				continue;
+			if (atomic_dec_and_test(&ppd->pkeyrefs[j])) {
+				ppd->pkeys[j] = 0;
+				pchanged++;
+			}
+			break;
+		}
+		rcd->pkeys[i] = 0;
+	}
+	if (pchanged)
+		(void) ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_PKEYS, 0);
+}
+
+/* common code for the mappings on dma_alloc_coherent mem */
+static int qib_mmap_mem(struct vm_area_struct *vma, struct qib_ctxtdata *rcd,
+			unsigned len, void *kvaddr, u32 write_ok, char *what)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned long pfn;
+	int ret;
+
+	if ((vma->vm_end - vma->vm_start) > len) {
+		qib_devinfo(dd->pcidev,
+			 "FAIL on %s: len %lx > %x\n", what,
+			 vma->vm_end - vma->vm_start, len);
+		ret = -EFAULT;
+		goto bail;
+	}
+
+	/*
+	 * shared context user code requires rcvhdrq mapped r/w, others
+	 * only allowed readonly mapping.
+	 */
+	if (!write_ok) {
+		if (vma->vm_flags & VM_WRITE) {
+			qib_devinfo(dd->pcidev,
+				 "%s must be mapped readonly\n", what);
+			ret = -EPERM;
+			goto bail;
+		}
+
+		/* don't allow them to later change with mprotect */
+		vma->vm_flags &= ~VM_MAYWRITE;
+	}
+
+	pfn = virt_to_phys(kvaddr) >> PAGE_SHIFT;
+	ret = remap_pfn_range(vma, vma->vm_start, pfn,
+			      len, vma->vm_page_prot);
+	if (ret)
+		qib_devinfo(dd->pcidev, "%s ctxt%u mmap of %lx, %x "
+			 "bytes failed: %d\n", what, rcd->ctxt,
+			 pfn, len, ret);
+bail:
+	return ret;
+}
+
+static int mmap_ureg(struct vm_area_struct *vma, struct qib_devdata *dd,
+		     u64 ureg)
+{
+	unsigned long phys;
+	unsigned long sz;
+	int ret;
+
+	/*
+	 * This is real hardware, so use io_remap.  This is the mechanism
+	 * for the user process to update the head registers for their ctxt
+	 * in the chip.
+	 */
+	sz = dd->flags & QIB_HAS_HDRSUPP ? 2 * PAGE_SIZE : PAGE_SIZE;
+	if ((vma->vm_end - vma->vm_start) > sz) {
+		qib_devinfo(dd->pcidev, "FAIL mmap userreg: reqlen "
+			 "%lx > PAGE\n", vma->vm_end - vma->vm_start);
+		ret = -EFAULT;
+	} else {
+		phys = dd->physaddr + ureg;
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+		vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
+		ret = io_remap_pfn_range(vma, vma->vm_start,
+					 phys >> PAGE_SHIFT,
+					 vma->vm_end - vma->vm_start,
+					 vma->vm_page_prot);
+	}
+	return ret;
+}
+
+static int mmap_piobufs(struct vm_area_struct *vma,
+			struct qib_devdata *dd,
+			struct qib_ctxtdata *rcd,
+			unsigned piobufs, unsigned piocnt)
+{
+	unsigned long phys;
+	int ret;
+
+	/*
+	 * When we map the PIO buffers in the chip, we want to map them as
+	 * writeonly, no read possible; unfortunately, x86 doesn't allow
+	 * for this in hardware, but we still prevent users from asking
+	 * for it.
+	 */
+	if ((vma->vm_end - vma->vm_start) > (piocnt * dd->palign)) {
+		qib_devinfo(dd->pcidev, "FAIL mmap piobufs: "
+			 "reqlen %lx > PAGE\n",
+			 vma->vm_end - vma->vm_start);
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	phys = dd->physaddr + piobufs;
+
+#if defined(__powerpc__)
+	/* There isn't a generic way to specify writethrough mappings */
+	pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
+	pgprot_val(vma->vm_page_prot) |= _PAGE_WRITETHRU;
+	pgprot_val(vma->vm_page_prot) &= ~_PAGE_GUARDED;
+#endif
+
+	/*
+	 * don't allow them to later change to readable with mprotect (for when
+	 * not initially mapped readable, as is normally the case)
+	 */
+	vma->vm_flags &= ~VM_MAYREAD;
+	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
+
+	if (qib_wc_pat)
+		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+
+	ret = io_remap_pfn_range(vma, vma->vm_start, phys >> PAGE_SHIFT,
+				 vma->vm_end - vma->vm_start,
+				 vma->vm_page_prot);
+bail:
+	return ret;
+}
+
+static int mmap_rcvegrbufs(struct vm_area_struct *vma,
+			   struct qib_ctxtdata *rcd)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned long start, size;
+	size_t total_size, i;
+	unsigned long pfn;
+	int ret;
+
+	size = rcd->rcvegrbuf_size;
+	total_size = rcd->rcvegrbuf_chunks * size;
+	if ((vma->vm_end - vma->vm_start) > total_size) {
+		qib_devinfo(dd->pcidev, "FAIL on egr bufs: "
+			 "reqlen %lx > actual %lx\n",
+			 vma->vm_end - vma->vm_start,
+			 (unsigned long) total_size);
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	if (vma->vm_flags & VM_WRITE) {
+		qib_devinfo(dd->pcidev, "Can't map eager buffers as "
+			 "writable (flags=%lx)\n", vma->vm_flags);
+		ret = -EPERM;
+		goto bail;
+	}
+	/* don't allow them to later change to writeable with mprotect */
+	vma->vm_flags &= ~VM_MAYWRITE;
+
+	start = vma->vm_start;
+
+	for (i = 0; i < rcd->rcvegrbuf_chunks; i++, start += size) {
+		pfn = virt_to_phys(rcd->rcvegrbuf[i]) >> PAGE_SHIFT;
+		ret = remap_pfn_range(vma, start, pfn, size,
+				      vma->vm_page_prot);
+		if (ret < 0)
+			goto bail;
+	}
+	ret = 0;
+
+bail:
+	return ret;
+}
+
+/*
+ * qib_file_vma_fault - handle a VMA page fault.
+ */
+static int qib_file_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct page *page;
+
+	page = vmalloc_to_page((void *)(vmf->pgoff << PAGE_SHIFT));
+	if (!page)
+		return VM_FAULT_SIGBUS;
+
+	get_page(page);
+	vmf->page = page;
+
+	return 0;
+}
+
+static struct vm_operations_struct qib_file_vm_ops = {
+	.fault = qib_file_vma_fault,
+};
+
+static int mmap_kvaddr(struct vm_area_struct *vma, u64 pgaddr,
+		       struct qib_ctxtdata *rcd, unsigned subctxt)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned subctxt_cnt;
+	unsigned long len;
+	void *addr;
+	size_t size;
+	int ret = 0;
+
+	subctxt_cnt = rcd->subctxt_cnt;
+	size = rcd->rcvegrbuf_chunks * rcd->rcvegrbuf_size;
+
+	/*
+	 * Each process has all the subctxt uregbase, rcvhdrq, and
+	 * rcvegrbufs mmapped - as an array for all the processes,
+	 * and also separately for this process.
+	 */
+	if (pgaddr == cvt_kvaddr(rcd->subctxt_uregbase)) {
+		addr = rcd->subctxt_uregbase;
+		size = PAGE_SIZE * subctxt_cnt;
+	} else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvhdr_base)) {
+		addr = rcd->subctxt_rcvhdr_base;
+		size = rcd->rcvhdrq_size * subctxt_cnt;
+	} else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvegrbuf)) {
+		addr = rcd->subctxt_rcvegrbuf;
+		size *= subctxt_cnt;
+	} else if (pgaddr == cvt_kvaddr(rcd->subctxt_uregbase +
+					PAGE_SIZE * subctxt)) {
+		addr = rcd->subctxt_uregbase + PAGE_SIZE * subctxt;
+		size = PAGE_SIZE;
+	} else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvhdr_base +
+					rcd->rcvhdrq_size * subctxt)) {
+		addr = rcd->subctxt_rcvhdr_base +
+			rcd->rcvhdrq_size * subctxt;
+		size = rcd->rcvhdrq_size;
+	} else if (pgaddr == cvt_kvaddr(&rcd->user_event_mask[subctxt])) {
+		addr = rcd->user_event_mask;
+		size = PAGE_SIZE;
+	} else if (pgaddr == cvt_kvaddr(rcd->subctxt_rcvegrbuf +
+					size * subctxt)) {
+		addr = rcd->subctxt_rcvegrbuf + size * subctxt;
+		/* rcvegrbufs are read-only on the slave */
+		if (vma->vm_flags & VM_WRITE) {
+			qib_devinfo(dd->pcidev,
+				 "Can't map eager buffers as "
+				 "writable (flags=%lx)\n", vma->vm_flags);
+			ret = -EPERM;
+			goto bail;
+		}
+		/*
+		 * Don't allow permission to later change to writeable
+		 * with mprotect.
+		 */
+		vma->vm_flags &= ~VM_MAYWRITE;
+	} else
+		goto bail;
+	len = vma->vm_end - vma->vm_start;
+	if (len > size) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	vma->vm_pgoff = (unsigned long) addr >> PAGE_SHIFT;
+	vma->vm_ops = &qib_file_vm_ops;
+	vma->vm_flags |= VM_RESERVED | VM_DONTEXPAND;
+	ret = 1;
+
+bail:
+	return ret;
+}
+
+/**
+ * qib_mmapf - mmap various structures into user space
+ * @fp: the file pointer
+ * @vma: the VM area
+ *
+ * We use this to have a shared buffer between the kernel and the user code
+ * for the rcvhdr queue, egr buffers, and the per-context user regs and pio
+ * buffers in the chip.  We have the open and close entries so we can bump
+ * the ref count and keep the driver from being unloaded while still mapped.
+ */
+static int qib_mmapf(struct file *fp, struct vm_area_struct *vma)
+{
+	struct qib_ctxtdata *rcd;
+	struct qib_devdata *dd;
+	u64 pgaddr, ureg;
+	unsigned piobufs, piocnt;
+	int ret, match = 1;
+
+	rcd = ctxt_fp(fp);
+	if (!rcd || !(vma->vm_flags & VM_SHARED)) {
+		ret = -EINVAL;
+		goto bail;
+	}
+	dd = rcd->dd;
+
+	/*
+	 * This is the qib_do_user_init() code, mapping the shared buffers
+	 * and per-context user registers into the user process. The address
+	 * referred to by vm_pgoff is the file offset passed via mmap().
+	 * For shared contexts, this is the kernel vmalloc() address of the
+	 * pages to share with the master.
+	 * For non-shared or master ctxts, this is a physical address.
+	 * We only do one mmap for each space mapped.
+	 */
+	pgaddr = vma->vm_pgoff << PAGE_SHIFT;
+
+	/*
+	 * Check for 0 in case one of the allocations failed, but user
+	 * called mmap anyway.
+	 */
+	if (!pgaddr)  {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	/*
+	 * Physical addresses must fit in 40 bits for our hardware.
+	 * Check for kernel virtual addresses first, anything else must
+	 * match a HW or memory address.
+	 */
+	ret = mmap_kvaddr(vma, pgaddr, rcd, subctxt_fp(fp));
+	if (ret) {
+		if (ret > 0)
+			ret = 0;
+		goto bail;
+	}
+
+	ureg = dd->uregbase + dd->ureg_align * rcd->ctxt;
+	if (!rcd->subctxt_cnt) {
+		/* ctxt is not shared */
+		piocnt = rcd->piocnt;
+		piobufs = rcd->piobufs;
+	} else if (!subctxt_fp(fp)) {
+		/* caller is the master */
+		piocnt = (rcd->piocnt / rcd->subctxt_cnt) +
+			 (rcd->piocnt % rcd->subctxt_cnt);
+		piobufs = rcd->piobufs +
+			dd->palign * (rcd->piocnt - piocnt);
+	} else {
+		unsigned slave = subctxt_fp(fp) - 1;
+
+		/* caller is a slave */
+		piocnt = rcd->piocnt / rcd->subctxt_cnt;
+		piobufs = rcd->piobufs + dd->palign * piocnt * slave;
+	}
+
+	if (pgaddr == ureg)
+		ret = mmap_ureg(vma, dd, ureg);
+	else if (pgaddr == piobufs)
+		ret = mmap_piobufs(vma, dd, rcd, piobufs, piocnt);
+	else if (pgaddr == dd->pioavailregs_phys)
+		/* in-memory copy of pioavail registers */
+		ret = qib_mmap_mem(vma, rcd, PAGE_SIZE,
+				   (void *) dd->pioavailregs_dma, 0,
+				   "pioavail registers");
+	else if (pgaddr == rcd->rcvegr_phys)
+		ret = mmap_rcvegrbufs(vma, rcd);
+	else if (pgaddr == (u64) rcd->rcvhdrq_phys)
+		/*
+		 * The rcvhdrq itself; multiple pages, contiguous
+		 * from an i/o perspective.  Shared contexts need
+		 * to map r/w, so we allow writing.
+		 */
+		ret = qib_mmap_mem(vma, rcd, rcd->rcvhdrq_size,
+				   rcd->rcvhdrq, 1, "rcvhdrq");
+	else if (pgaddr == (u64) rcd->rcvhdrqtailaddr_phys)
+		/* in-memory copy of rcvhdrq tail register */
+		ret = qib_mmap_mem(vma, rcd, PAGE_SIZE,
+				   rcd->rcvhdrtail_kvaddr, 0,
+				   "rcvhdrq tail");
+	else
+		match = 0;
+	if (!match)
+		ret = -EINVAL;
+
+	vma->vm_private_data = NULL;
+
+	if (ret < 0)
+		qib_devinfo(dd->pcidev,
+			 "mmap Failure %d: off %llx len %lx\n",
+			 -ret, (unsigned long long)pgaddr,
+			 vma->vm_end - vma->vm_start);
+bail:
+	return ret;
+}
+
+static unsigned int qib_poll_urgent(struct qib_ctxtdata *rcd,
+				    struct file *fp,
+				    struct poll_table_struct *pt)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned pollflag;
+
+	poll_wait(fp, &rcd->wait, pt);
+
+	spin_lock_irq(&dd->uctxt_lock);
+	if (rcd->urgent != rcd->urgent_poll) {
+		pollflag = POLLIN | POLLRDNORM;
+		rcd->urgent_poll = rcd->urgent;
+	} else {
+		pollflag = 0;
+		set_bit(QIB_CTXT_WAITING_URG, &rcd->flag);
+	}
+	spin_unlock_irq(&dd->uctxt_lock);
+
+	return pollflag;
+}
+
+static unsigned int qib_poll_next(struct qib_ctxtdata *rcd,
+				  struct file *fp,
+				  struct poll_table_struct *pt)
+{
+	struct qib_devdata *dd = rcd->dd;
+	unsigned pollflag;
+
+	poll_wait(fp, &rcd->wait, pt);
+
+	spin_lock_irq(&dd->uctxt_lock);
+	if (dd->f_hdrqempty(rcd)) {
+		set_bit(QIB_CTXT_WAITING_RCV, &rcd->flag);
+		dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_INTRAVAIL_ENB, rcd->ctxt);
+		pollflag = 0;
+	} else
+		pollflag = POLLIN | POLLRDNORM;
+	spin_unlock_irq(&dd->uctxt_lock);
+
+	return pollflag;
+}
+
+static unsigned int qib_poll(struct file *fp, struct poll_table_struct *pt)
+{
+	struct qib_ctxtdata *rcd;
+	unsigned pollflag;
+
+	rcd = ctxt_fp(fp);
+	if (!rcd)
+		pollflag = POLLERR;
+	else if (rcd->poll_type == QIB_POLL_TYPE_URGENT)
+		pollflag = qib_poll_urgent(rcd, fp, pt);
+	else  if (rcd->poll_type == QIB_POLL_TYPE_ANYRCV)
+		pollflag = qib_poll_next(rcd, fp, pt);
+	else /* invalid */
+		pollflag = POLLERR;
+
+	return pollflag;
+}
+
+/*
+ * Check that userland and driver are compatible for subcontexts.
+ */
+static int qib_compatible_subctxts(int user_swmajor, int user_swminor)
+{
+	/* this code is written long-hand for clarity */
+	if (QIB_USER_SWMAJOR != user_swmajor) {
+		/* no promise of compatibility if major mismatch */
+		return 0;
+	}
+	if (QIB_USER_SWMAJOR == 1) {
+		switch (QIB_USER_SWMINOR) {
+		case 0:
+		case 1:
+		case 2:
+			/* no subctxt implementation so cannot be compatible */
+			return 0;
+		case 3:
+			/* 3 is only compatible with itself */
+			return user_swminor == 3;
+		default:
+			/* >= 4 are compatible (or are expected to be) */
+			return user_swminor >= 4;
+		}
+	}
+	/* make no promises yet for future major versions */
+	return 0;
+}
+
+static int init_subctxts(struct qib_devdata *dd,
+			 struct qib_ctxtdata *rcd,
+			 const struct qib_user_info *uinfo)
+{
+	int ret = 0;
+	unsigned num_subctxts;
+	size_t size;
+
+	/*
+	 * If the user is requesting zero subctxts,
+	 * skip the subctxt allocation.
+	 */
+	if (uinfo->spu_subctxt_cnt <= 0)
+		goto bail;
+	num_subctxts = uinfo->spu_subctxt_cnt;
+
+	/* Check for subctxt compatibility */
+	if (!qib_compatible_subctxts(uinfo->spu_userversion >> 16,
+		uinfo->spu_userversion & 0xffff)) {
+		qib_devinfo(dd->pcidev,
+			 "Mismatched user version (%d.%d) and driver "
+			 "version (%d.%d) while context sharing. Ensure "
+			 "that driver and library are from the same "
+			 "release.\n",
+			 (int) (uinfo->spu_userversion >> 16),
+			 (int) (uinfo->spu_userversion & 0xffff),
+			 QIB_USER_SWMAJOR, QIB_USER_SWMINOR);
+		goto bail;
+	}
+	if (num_subctxts > QLOGIC_IB_MAX_SUBCTXT) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	rcd->subctxt_uregbase = vmalloc_user(PAGE_SIZE * num_subctxts);
+	if (!rcd->subctxt_uregbase) {
+		ret = -ENOMEM;
+		goto bail;
+	}
+	/* Note: rcd->rcvhdrq_size isn't initialized yet. */
+	size = ALIGN(dd->rcvhdrcnt * dd->rcvhdrentsize *
+		     sizeof(u32), PAGE_SIZE) * num_subctxts;
+	rcd->subctxt_rcvhdr_base = vmalloc_user(size);
+	if (!rcd->subctxt_rcvhdr_base) {
+		ret = -ENOMEM;
+		goto bail_ureg;
+	}
+
+	rcd->subctxt_rcvegrbuf = vmalloc_user(rcd->rcvegrbuf_chunks *
+					      rcd->rcvegrbuf_size *
+					      num_subctxts);
+	if (!rcd->subctxt_rcvegrbuf) {
+		ret = -ENOMEM;
+		goto bail_rhdr;
+	}
+
+	rcd->subctxt_cnt = uinfo->spu_subctxt_cnt;
+	rcd->subctxt_id = uinfo->spu_subctxt_id;
+	rcd->active_slaves = 1;
+	rcd->redirect_seq_cnt = 1;
+	set_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag);
+	goto bail;
+
+bail_rhdr:
+	vfree(rcd->subctxt_rcvhdr_base);
+bail_ureg:
+	vfree(rcd->subctxt_uregbase);
+	rcd->subctxt_uregbase = NULL;
+bail:
+	return ret;
+}
+
+static int setup_ctxt(struct qib_pportdata *ppd, int ctxt,
+		      struct file *fp, const struct qib_user_info *uinfo)
+{
+	struct qib_devdata *dd = ppd->dd;
+	struct qib_ctxtdata *rcd;
+	void *ptmp = NULL;
+	int ret;
+
+	rcd = qib_create_ctxtdata(ppd, ctxt);
+
+	/*
+	 * Allocate memory for use in qib_tid_update() at open to
+	 * reduce cost of expected send setup per message segment
+	 */
+	if (rcd)
+		ptmp = kmalloc(dd->rcvtidcnt * sizeof(u16) +
+			       dd->rcvtidcnt * sizeof(struct page **),
+			       GFP_KERNEL);
+
+	if (!rcd || !ptmp) {
+		qib_dev_err(dd, "Unable to allocate ctxtdata "
+			    "memory, failing open\n");
+		ret = -ENOMEM;
+		goto bailerr;
+	}
+	rcd->userversion = uinfo->spu_userversion;
+	ret = init_subctxts(dd, rcd, uinfo);
+	if (ret)
+		goto bailerr;
+	rcd->tid_pg_list = ptmp;
+	rcd->pid = current->pid;
+	init_waitqueue_head(&dd->rcd[ctxt]->wait);
+	strlcpy(rcd->comm, current->comm, sizeof(rcd->comm));
+	ctxt_fp(fp) = rcd;
+	qib_stats.sps_ctxts++;
+	ret = 0;
+	goto bail;
+
+bailerr:
+	dd->rcd[ctxt] = NULL;
+	kfree(rcd);
+	kfree(ptmp);
+bail:
+	return ret;
+}
+
+static inline int usable(struct qib_pportdata *ppd, int active_only)
+{
+	struct qib_devdata *dd = ppd->dd;
+	u32 linkok = active_only ? QIBL_LINKACTIVE :
+		 (QIBL_LINKINIT | QIBL_LINKARMED | QIBL_LINKACTIVE);
+
+	return dd && (dd->flags & QIB_PRESENT) && dd->kregbase && ppd->lid &&
+		(ppd->lflags & linkok);
+}
+
+static int find_free_ctxt(int unit, struct file *fp,
+			  const struct qib_user_info *uinfo)
+{
+	struct qib_devdata *dd = qib_lookup(unit);
+	struct qib_pportdata *ppd = NULL;
+	int ret;
+	u32 ctxt;
+
+	if (!dd || (uinfo->spu_port && uinfo->spu_port > dd->num_pports)) {
+		ret = -ENODEV;
+		goto bail;
+	}
+
+	/*
+	 * If users requests specific port, only try that one port, else
+	 * select "best" port below, based on context.
+	 */
+	if (uinfo->spu_port) {
+		ppd = dd->pport + uinfo->spu_port - 1;
+		if (!usable(ppd, 0)) {
+			ret = -ENETDOWN;
+			goto bail;
+		}
+	}
+
+	for (ctxt = dd->first_user_ctxt; ctxt < dd->cfgctxts; ctxt++) {
+		if (dd->rcd[ctxt])
+			continue;
+		/*
+		 * The setting and clearing of user context rcd[x] protected
+		 * by the qib_mutex
+		 */
+		if (!ppd) {
+			/* choose port based on ctxt, if up, else 1st up */
+			ppd = dd->pport + (ctxt % dd->num_pports);
+			if (!usable(ppd, 0)) {
+				int i;
+				for (i = 0; i < dd->num_pports; i++) {
+					ppd = dd->pport + i;
+					if (usable(ppd, 0))
+						break;
+				}
+				if (i == dd->num_pports) {
+					ret = -ENETDOWN;
+					goto bail;
+				}
+			}
+		}
+		ret = setup_ctxt(ppd, ctxt, fp, uinfo);
+		goto bail;
+	}
+	ret = -EBUSY;
+
+bail:
+	return ret;
+}
+
+static int get_a_ctxt(struct file *fp, const struct qib_user_info *uinfo)
+{
+	struct qib_pportdata *ppd;
+	int ret = 0, devmax;
+	int npresent, nup;
+	int ndev;
+	u32 port = uinfo->spu_port, ctxt;
+
+	devmax = qib_count_units(&npresent, &nup);
+
+	for (ndev = 0; ndev < devmax; ndev++) {
+		struct qib_devdata *dd = qib_lookup(ndev);
+
+		/* device portion of usable() */
+		if (!(dd && (dd->flags & QIB_PRESENT) && dd->kregbase))
+			continue;
+		for (ctxt = dd->first_user_ctxt; ctxt < dd->cfgctxts; ctxt++) {
+			if (dd->rcd[ctxt])
+				continue;
+			if (port) {
+				if (port > dd->num_pports)
+					continue;
+				ppd = dd->pport + port - 1;
+				if (!usable(ppd, 0))
+					continue;
+			} else {
+				/*
+				 * choose port based on ctxt, if up, else
+				 * first port that's up for multi-port HCA
+				 */
+				ppd = dd->pport + (ctxt % dd->num_pports);
+				if (!usable(ppd, 0)) {
+					int j;
+
+					ppd = NULL;
+					for (j = 0; j < dd->num_pports &&
+						!ppd; j++)
+						if (usable(dd->pport + j, 0))
+							ppd = dd->pport + j;
+					if (!ppd)
+						continue; /* to next unit */
+				}
+			}
+			ret = setup_ctxt(ppd, ctxt, fp, uinfo);
+			goto done;
+		}
+	}
+
+	if (npresent) {
+		if (nup == 0)
+			ret = -ENETDOWN;
+		else
+			ret = -EBUSY;
+	} else
+		ret = -ENXIO;
+
+done:
+	return ret;
+}
+
+static int find_shared_ctxt(struct file *fp,
+			    const struct qib_user_info *uinfo)
+{
+	int devmax, ndev, i;
+	int ret = 0;
+
+	devmax = qib_count_units(NULL, NULL);
+
+	for (ndev = 0; ndev < devmax; ndev++) {
+		struct qib_devdata *dd = qib_lookup(ndev);
+
+		/* device portion of usable() */
+		if (!(dd && (dd->flags & QIB_PRESENT) && dd->kregbase))
+			continue;
+		for (i = dd->first_user_ctxt; i < dd->cfgctxts; i++) {
+			struct qib_ctxtdata *rcd = dd->rcd[i];
+
+			/* Skip ctxts which are not yet open */
+			if (!rcd || !rcd->cnt)
+				continue;
+			/* Skip ctxt if it doesn't match the requested one */
+			if (rcd->subctxt_id != uinfo->spu_subctxt_id)
+				continue;
+			/* Verify the sharing process matches the master */
+			if (rcd->subctxt_cnt != uinfo->spu_subctxt_cnt ||
+			    rcd->userversion != uinfo->spu_userversion ||
+			    rcd->cnt >= rcd->subctxt_cnt) {
+				ret = -EINVAL;
+				goto done;
+			}
+			ctxt_fp(fp) = rcd;
+			subctxt_fp(fp) = rcd->cnt++;
+			rcd->subpid[subctxt_fp(fp)] = current->pid;
+			tidcursor_fp(fp) = 0;
+			rcd->active_slaves |= 1 << subctxt_fp(fp);
+			ret = 1;
+			goto done;
+		}
+	}
+
+done:
+	return ret;
+}
+
+static int qib_open(struct inode *in, struct file *fp)
+{
+	/* The real work is performed later in qib_assign_ctxt() */
+	fp->private_data = kzalloc(sizeof(struct qib_filedata), GFP_KERNEL);
+	if (fp->private_data) /* no cpu affinity by default */
+		((struct qib_filedata *)fp->private_data)->rec_cpu_num = -1;
+	return fp->private_data ? 0 : -ENOMEM;
+}
+
+/*
+ * Get ctxt early, so can set affinity prior to memory allocation.
+ */
+static int qib_assign_ctxt(struct file *fp, const struct qib_user_info *uinfo)
+{
+	int ret;
+	int i_minor;
+	unsigned swmajor, swminor;
+
+	/* Check to be sure we haven't already initialized this file */
+	if (ctxt_fp(fp)) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	/* for now, if major version is different, bail */
+	swmajor = uinfo->spu_userversion >> 16;
+	if (swmajor != QIB_USER_SWMAJOR) {
+		ret = -ENODEV;
+		goto done;
+	}
+
+	swminor = uinfo->spu_userversion & 0xffff;
+
+	mutex_lock(&qib_mutex);
+
+	if (qib_compatible_subctxts(swmajor, swminor) &&
+	    uinfo->spu_subctxt_cnt) {
+		ret = find_shared_ctxt(fp, uinfo);
+		if (ret) {
+			if (ret > 0)
+				ret = 0;
+			goto done_chk_sdma;
+		}
+	}
+
+	i_minor = iminor(fp->f_dentry->d_inode) - QIB_USER_MINOR_BASE;
+	if (i_minor)
+		ret = find_free_ctxt(i_minor - 1, fp, uinfo);
+	else
+		ret = get_a_ctxt(fp, uinfo);
+
+done_chk_sdma:
+	if (!ret) {
+		struct qib_filedata *fd = fp->private_data;
+		const struct qib_ctxtdata *rcd = fd->rcd;
+		const struct qib_devdata *dd = rcd->dd;
+
+		if (dd->flags & QIB_HAS_SEND_DMA) {
+			fd->pq = qib_user_sdma_queue_create(&dd->pcidev->dev,
+							    dd->unit,
+							    rcd->ctxt,
+							    fd->subctxt);
+			if (!fd->pq)
+				ret = -ENOMEM;
+		}
+
+		/*
+		 * If process has NOT already set it's affinity, select and
+		 * reserve a processor for it, as a rendevous for all
+		 * users of the driver.  If they don't actually later
+		 * set affinity to this cpu, or set it to some other cpu,
+		 * it just means that sooner or later we don't recommend
+		 * a cpu, and let the scheduler do it's best.
+		 */
+		if (!ret && cpus_weight(current->cpus_allowed) >=
+		    qib_cpulist_count) {
+			int cpu;
+			cpu = find_first_zero_bit(qib_cpulist,
+						  qib_cpulist_count);
+			if (cpu != qib_cpulist_count) {
+				__set_bit(cpu, qib_cpulist);
+				fd->rec_cpu_num = cpu;
+			}
+		} else if (cpus_weight(current->cpus_allowed) == 1 &&
+			test_bit(first_cpu(current->cpus_allowed),
+				 qib_cpulist))
+			qib_devinfo(dd->pcidev, "%s PID %u affinity "
+				    "set to cpu %d; already allocated\n",
+				    current->comm, current->pid,
+				    first_cpu(current->cpus_allowed));
+	}
+
+	mutex_unlock(&qib_mutex);
+
+done:
+	return ret;
+}
+
+
+static int qib_do_user_init(struct file *fp,
+			    const struct qib_user_info *uinfo)
+{
+	int ret;
+	struct qib_ctxtdata *rcd = ctxt_fp(fp);
+	struct qib_devdata *dd;
+	unsigned uctxt;
+
+	/* Subctxts don't need to initialize anything since master did it. */
+	if (subctxt_fp(fp)) {
+		ret = wait_event_interruptible(rcd->wait,
+			!test_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag));
+		goto bail;
+	}
+
+	dd = rcd->dd;
+
+	/* some ctxts may get extra buffers, calculate that here */
+	uctxt = rcd->ctxt - dd->first_user_ctxt;
+	if (uctxt < dd->ctxts_extrabuf) {
+		rcd->piocnt = dd->pbufsctxt + 1;
+		rcd->pio_base = rcd->piocnt * uctxt;
+	} else {
+		rcd->piocnt = dd->pbufsctxt;
+		rcd->pio_base = rcd->piocnt * uctxt +
+			dd->ctxts_extrabuf;
+	}
+
+	/*
+	 * All user buffers are 2KB buffers.  If we ever support
+	 * giving 4KB buffers to user processes, this will need some
+	 * work.  Can't use piobufbase directly, because it has
+	 * both 2K and 4K buffer base values.  So check and handle.
+	 */
+	if ((rcd->pio_base + rcd->piocnt) > dd->piobcnt2k) {
+		if (rcd->pio_base >= dd->piobcnt2k) {
+			qib_dev_err(dd,
+				    "%u:ctxt%u: no 2KB buffers available\n",
+				    dd->unit, rcd->ctxt);
+			ret = -ENOBUFS;
+			goto bail;
+		}
+		rcd->piocnt = dd->piobcnt2k - rcd->pio_base;
+		qib_dev_err(dd, "Ctxt%u: would use 4KB bufs, using %u\n",
+			    rcd->ctxt, rcd->piocnt);
+	}
+
+	rcd->piobufs = dd->pio2k_bufbase + rcd->pio_base * dd->palign;
+	qib_chg_pioavailkernel(dd, rcd->pio_base, rcd->piocnt,
+			       TXCHK_CHG_TYPE_USER, rcd);
+	/*
+	 * try to ensure that processes start up with consistent avail update
+	 * for their own range, at least.   If system very quiet, it might
+	 * have the in-memory copy out of date at startup for this range of
+	 * buffers, when a context gets re-used.  Do after the chg_pioavail
+	 * and before the rest of setup, so it's "almost certain" the dma
+	 * will have occurred (can't 100% guarantee, but should be many
+	 * decimals of 9s, with this ordering), given how much else happens
+	 * after this.
+	 */
+	dd->f_sendctrl(dd->pport, QIB_SENDCTRL_AVAIL_BLIP);
+
+	/*
+	 * Now allocate the rcvhdr Q and eager TIDs; skip the TID
+	 * array for time being.  If rcd->ctxt > chip-supported,
+	 * we need to do extra stuff here to handle by handling overflow
+	 * through ctxt 0, someday
+	 */
+	ret = qib_create_rcvhdrq(dd, rcd);
+	if (!ret)
+		ret = qib_setup_eagerbufs(rcd);
+	if (ret)
+		goto bail_pio;
+
+	rcd->tidcursor = 0; /* start at beginning after open */
+
+	/* initialize poll variables... */
+	rcd->urgent = 0;
+	rcd->urgent_poll = 0;
+
+	/*
+	 * Now enable the ctxt for receive.
+	 * For chips that are set to DMA the tail register to memory
+	 * when they change (and when the update bit transitions from
+	 * 0 to 1.  So for those chips, we turn it off and then back on.
+	 * This will (very briefly) affect any other open ctxts, but the
+	 * duration is very short, and therefore isn't an issue.  We
+	 * explictly set the in-memory tail copy to 0 beforehand, so we
+	 * don't have to wait to be sure the DMA update has happened
+	 * (chip resets head/tail to 0 on transition to enable).
+	 */
+	if (rcd->rcvhdrtail_kvaddr)
+		qib_clear_rcvhdrtail(rcd);
+
+	dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_CTXT_ENB | QIB_RCVCTRL_TIDFLOW_ENB,
+		      rcd->ctxt);
+
+	/* Notify any waiting slaves */
+	if (rcd->subctxt_cnt) {
+		clear_bit(QIB_CTXT_MASTER_UNINIT, &rcd->flag);
+		wake_up(&rcd->wait);
+	}
+	return 0;
+
+bail_pio:
+	qib_chg_pioavailkernel(dd, rcd->pio_base, rcd->piocnt,
+			       TXCHK_CHG_TYPE_KERN, rcd);
+bail:
+	return ret;
+}
+
+/**
+ * unlock_exptid - unlock any expected TID entries context still had in use
+ * @rcd: ctxt
+ *
+ * We don't actually update the chip here, because we do a bulk update
+ * below, using f_clear_tids.
+ */
+static void unlock_expected_tids(struct qib_ctxtdata *rcd)
+{
+	struct qib_devdata *dd = rcd->dd;
+	int ctxt_tidbase = rcd->ctxt * dd->rcvtidcnt;
+	int i, cnt = 0, maxtid = ctxt_tidbase + dd->rcvtidcnt;
+
+	for (i = ctxt_tidbase; i < maxtid; i++) {
+		struct page *p = dd->pageshadow[i];
+		dma_addr_t phys;
+
+		if (!p)
+			continue;
+
+		phys = dd->physshadow[i];
+		dd->physshadow[i] = dd->tidinvalid;
+		dd->pageshadow[i] = NULL;
+		pci_unmap_page(dd->pcidev, phys, PAGE_SIZE,
+			       PCI_DMA_FROMDEVICE);
+		qib_release_user_pages(&p, 1);
+		cnt++;
+	}
+}
+
+static int qib_close(struct inode *in, struct file *fp)
+{
+	int ret = 0;
+	struct qib_filedata *fd;
+	struct qib_ctxtdata *rcd;
+	struct qib_devdata *dd;
+	unsigned long flags;
+	unsigned ctxt;
+	pid_t pid;
+
+	mutex_lock(&qib_mutex);
+
+	fd = (struct qib_filedata *) fp->private_data;
+	fp->private_data = NULL;
+	rcd = fd->rcd;
+	if (!rcd) {
+		mutex_unlock(&qib_mutex);
+		goto bail;
+	}
+
+	dd = rcd->dd;
+
+	/* ensure all pio buffer writes in progress are flushed */
+	qib_flush_wc();
+
+	/* drain user sdma queue */
+	if (fd->pq) {
+		qib_user_sdma_queue_drain(rcd->ppd, fd->pq);
+		qib_user_sdma_queue_destroy(fd->pq);
+	}
+
+	if (fd->rec_cpu_num != -1)
+		__clear_bit(fd->rec_cpu_num, qib_cpulist);
+
+	if (--rcd->cnt) {
+		/*
+		 * XXX If the master closes the context before the slave(s),
+		 * revoke the mmap for the eager receive queue so
+		 * the slave(s) don't wait for receive data forever.
+		 */
+		rcd->active_slaves &= ~(1 << fd->subctxt);
+		rcd->subpid[fd->subctxt] = 0;
+		mutex_unlock(&qib_mutex);
+		goto bail;
+	}
+
+	/* early; no interrupt users after this */
+	spin_lock_irqsave(&dd->uctxt_lock, flags);
+	ctxt = rcd->ctxt;
+	dd->rcd[ctxt] = NULL;
+	pid = rcd->pid;
+	rcd->pid = 0;
+	spin_unlock_irqrestore(&dd->uctxt_lock, flags);
+
+	if (rcd->rcvwait_to || rcd->piowait_to ||
+	    rcd->rcvnowait || rcd->pionowait) {
+		rcd->rcvwait_to = 0;
+		rcd->piowait_to = 0;
+		rcd->rcvnowait = 0;
+		rcd->pionowait = 0;
+	}
+	if (rcd->flag)
+		rcd->flag = 0;
+
+	if (dd->kregbase) {
+		/* atomically clear receive enable ctxt and intr avail. */
+		dd->f_rcvctrl(rcd->ppd, QIB_RCVCTRL_CTXT_DIS |
+				  QIB_RCVCTRL_INTRAVAIL_DIS, ctxt);
+
+		/* clean up the pkeys for this ctxt user */
+		qib_clean_part_key(rcd, dd);
+		qib_disarm_piobufs(dd, rcd->pio_base, rcd->piocnt);
+		qib_chg_pioavailkernel(dd, rcd->pio_base,
+				       rcd->piocnt, TXCHK_CHG_TYPE_KERN, NULL);
+
+		dd->f_clear_tids(dd, rcd);
+
+		if (dd->pageshadow)
+			unlock_expected_tids(rcd);
+		qib_stats.sps_ctxts--;
+	}
+
+	mutex_unlock(&qib_mutex);
+	qib_free_ctxtdata(dd, rcd); /* after releasing the mutex */
+
+bail:
+	kfree(fd);
+	return ret;
+}
+
+static int qib_ctxt_info(struct file *fp, struct qib_ctxt_info __user *uinfo)
+{
+	struct qib_ctxt_info info;
+	int ret;
+	size_t sz;
+	struct qib_ctxtdata *rcd = ctxt_fp(fp);
+	struct qib_filedata *fd;
+
+	fd = (struct qib_filedata *) fp->private_data;
+
+	info.num_active = qib_count_active_units();
+	info.unit = rcd->dd->unit;
+	info.port = rcd->ppd->port;
+	info.ctxt = rcd->ctxt;
+	info.subctxt =  subctxt_fp(fp);
+	/* Number of user ctxts available for this device. */
+	info.num_ctxts = rcd->dd->cfgctxts - rcd->dd->first_user_ctxt;
+	info.num_subctxts = rcd->subctxt_cnt;
+	info.rec_cpu = fd->rec_cpu_num;
+	sz = sizeof(info);
+
+	if (copy_to_user(uinfo, &info, sz)) {
+		ret = -EFAULT;
+		goto bail;
+	}
+	ret = 0;
+
+bail:
+	return ret;
+}
+
+static int qib_sdma_get_inflight(struct qib_user_sdma_queue *pq,
+				 u32 __user *inflightp)
+{
+	const u32 val = qib_user_sdma_inflight_counter(pq);
+
+	if (put_user(val, inflightp))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int qib_sdma_get_complete(struct qib_pportdata *ppd,
+				 struct qib_user_sdma_queue *pq,
+				 u32 __user *completep)
+{
+	u32 val;
+	int err;
+
+	if (!pq)
+		return -EINVAL;
+
+	err = qib_user_sdma_make_progress(ppd, pq);
+	if (err < 0)
+		return err;
+
+	val = qib_user_sdma_complete_counter(pq);
+	if (put_user(val, completep))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int disarm_req_delay(struct qib_ctxtdata *rcd)
+{
+	int ret = 0;
+
+	if (!usable(rcd->ppd, 1)) {
+		int i;
+		/*
+		 * if link is down, or otherwise not usable, delay
+		 * the caller up to 30 seconds, so we don't thrash
+		 * in trying to get the chip back to ACTIVE, and
+		 * set flag so they make the call again.
+		 */
+		if (rcd->user_event_mask) {
+			/*
+			 * subctxt_cnt is 0 if not shared, so do base
+			 * separately, first, then remaining subctxt, if any
+			 */
+			set_bit(_QIB_EVENT_DISARM_BUFS_BIT,
+				&rcd->user_event_mask[0]);
+			for (i = 1; i < rcd->subctxt_cnt; i++)
+				set_bit(_QIB_EVENT_DISARM_BUFS_BIT,
+					&rcd->user_event_mask[i]);
+		}
+		for (i = 0; !usable(rcd->ppd, 1) && i < 300; i++)
+			msleep(100);
+		ret = -ENETDOWN;
+	}
+	return ret;
+}
+
+/*
+ * Find all user contexts in use, and set the specified bit in their
+ * event mask.
+ * See also find_ctxt() for a similar use, that is specific to send buffers.
+ */
+int qib_set_uevent_bits(struct qib_pportdata *ppd, const int evtbit)
+{
+	struct qib_ctxtdata *rcd;
+	unsigned ctxt;
+	int ret = 0;
+
+	spin_lock(&ppd->dd->uctxt_lock);
+	for (ctxt = ppd->dd->first_user_ctxt; ctxt < ppd->dd->cfgctxts;
+	     ctxt++) {
+		rcd = ppd->dd->rcd[ctxt];
+		if (!rcd)
+			continue;
+		if (rcd->user_event_mask) {
+			int i;
+			/*
+			 * subctxt_cnt is 0 if not shared, so do base
+			 * separately, first, then remaining subctxt, if any
+			 */
+			set_bit(evtbit, &rcd->user_event_mask[0]);
+			for (i = 1; i < rcd->subctxt_cnt; i++)
+				set_bit(evtbit, &rcd->user_event_mask[i]);
+		}
+		ret = 1;
+		break;
+	}
+	spin_unlock(&ppd->dd->uctxt_lock);
+
+	return ret;
+}
+
+/*
+ * clear the event notifier events for this context.
+ * For the DISARM_BUFS case, we also take action (this obsoletes
+ * the older QIB_CMD_DISARM_BUFS, but we keep it for backwards
+ * compatibility.
+ * Other bits don't currently require actions, just atomically clear.
+ * User process then performs actions appropriate to bit having been
+ * set, if desired, and checks again in future.
+ */
+static int qib_user_event_ack(struct qib_ctxtdata *rcd, int subctxt,
+			      unsigned long events)
+{
+	int ret = 0, i;
+
+	for (i = 0; i <= _QIB_MAX_EVENT_BIT; i++) {
+		if (!test_bit(i, &events))
+			continue;
+		if (i == _QIB_EVENT_DISARM_BUFS_BIT) {
+			(void)qib_disarm_piobufs_ifneeded(rcd);
+			ret = disarm_req_delay(rcd);
+		} else
+			clear_bit(i, &rcd->user_event_mask[subctxt]);
+	}
+	return ret;
+}
+
+static ssize_t qib_write(struct file *fp, const char __user *data,
+			 size_t count, loff_t *off)
+{
+	const struct qib_cmd __user *ucmd;
+	struct qib_ctxtdata *rcd;
+	const void __user *src;
+	size_t consumed, copy = 0;
+	struct qib_cmd cmd;
+	ssize_t ret = 0;
+	void *dest;
+
+	if (count < sizeof(cmd.type)) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	ucmd = (const struct qib_cmd __user *) data;
+
+	if (copy_from_user(&cmd.type, &ucmd->type, sizeof(cmd.type))) {
+		ret = -EFAULT;
+		goto bail;
+	}
+
+	consumed = sizeof(cmd.type);
+
+	switch (cmd.type) {
+	case QIB_CMD_ASSIGN_CTXT:
+	case QIB_CMD_USER_INIT:
+		copy = sizeof(cmd.cmd.user_info);
+		dest = &cmd.cmd.user_info;
+		src = &ucmd->cmd.user_info;
+		break;
+
+	case QIB_CMD_RECV_CTRL:
+		copy = sizeof(cmd.cmd.recv_ctrl);
+		dest = &cmd.cmd.recv_ctrl;
+		src = &ucmd->cmd.recv_ctrl;
+		break;
+
+	case QIB_CMD_CTXT_INFO:
+		copy = sizeof(cmd.cmd.ctxt_info);
+		dest = &cmd.cmd.ctxt_info;
+		src = &ucmd->cmd.ctxt_info;
+		break;
+
+	case QIB_CMD_TID_UPDATE:
+	case QIB_CMD_TID_FREE:
+		copy = sizeof(cmd.cmd.tid_info);
+		dest = &cmd.cmd.tid_info;
+		src = &ucmd->cmd.tid_info;
+		break;
+
+	case QIB_CMD_SET_PART_KEY:
+		copy = sizeof(cmd.cmd.part_key);
+		dest = &cmd.cmd.part_key;
+		src = &ucmd->cmd.part_key;
+		break;
+
+	case QIB_CMD_DISARM_BUFS:
+	case QIB_CMD_PIOAVAILUPD: /* force an update of PIOAvail reg */
+		copy = 0;
+		src = NULL;
+		dest = NULL;
+		break;
+
+	case QIB_CMD_POLL_TYPE:
+		copy = sizeof(cmd.cmd.poll_type);
+		dest = &cmd.cmd.poll_type;
+		src = &ucmd->cmd.poll_type;
+		break;
+
+	case QIB_CMD_ARMLAUNCH_CTRL:
+		copy = sizeof(cmd.cmd.armlaunch_ctrl);
+		dest = &cmd.cmd.armlaunch_ctrl;
+		src = &ucmd->cmd.armlaunch_ctrl;
+		break;
+
+	case QIB_CMD_SDMA_INFLIGHT:
+		copy = sizeof(cmd.cmd.sdma_inflight);
+		dest = &cmd.cmd.sdma_inflight;
+		src = &ucmd->cmd.sdma_inflight;
+		break;
+
+	case QIB_CMD_SDMA_COMPLETE:
+		copy = sizeof(cmd.cmd.sdma_complete);
+		dest = &cmd.cmd.sdma_complete;
+		src = &ucmd->cmd.sdma_complete;
+		break;
+
+	case QIB_CMD_ACK_EVENT:
+		copy = sizeof(cmd.cmd.event_mask);
+		dest = &cmd.cmd.event_mask;
+		src = &ucmd->cmd.event_mask;
+		break;
+
+	default:
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	if (copy) {
+		if ((count - consumed) < copy) {
+			ret = -EINVAL;
+			goto bail;
+		}
+		if (copy_from_user(dest, src, copy)) {
+			ret = -EFAULT;
+			goto bail;
+		}
+		consumed += copy;
+	}
+
+	rcd = ctxt_fp(fp);
+	if (!rcd && cmd.type != QIB_CMD_ASSIGN_CTXT) {
+		ret = -EINVAL;
+		goto bail;
+	}
+
+	switch (cmd.type) {
+	case QIB_CMD_ASSIGN_CTXT:
+		ret = qib_assign_ctxt(fp, &cmd.cmd.user_info);
+		if (ret)
+			goto bail;
+		break;
+
+	case QIB_CMD_USER_INIT:
+		ret = qib_do_user_init(fp, &cmd.cmd.user_info);
+		if (ret)
+			goto bail;
+		ret = qib_get_base_info(fp, (void __user *) (unsigned long)
+					cmd.cmd.user_info.spu_base_info,
+					cmd.cmd.user_info.spu_base_info_size);
+		break;
+
+	case QIB_CMD_RECV_CTRL:
+		ret = qib_manage_rcvq(rcd, subctxt_fp(fp), cmd.cmd.recv_ctrl);
+		break;
+
+	case QIB_CMD_CTXT_INFO:
+		ret = qib_ctxt_info(fp, (struct qib_ctxt_info __user *)
+				    (unsigned long) cmd.cmd.ctxt_info);
+		break;
+
+	case QIB_CMD_TID_UPDATE:
+		ret = qib_tid_update(rcd, fp, &cmd.cmd.tid_info);
+		break;
+
+	case QIB_CMD_TID_FREE:
+		ret = qib_tid_free(rcd, subctxt_fp(fp), &cmd.cmd.tid_info);
+		break;
+
+	case QIB_CMD_SET_PART_KEY:
+		ret = qib_set_part_key(rcd, cmd.cmd.part_key);
+		break;
+
+	case QIB_CMD_DISARM_BUFS:
+		(void)qib_disarm_piobufs_ifneeded(rcd);
+		ret = disarm_req_delay(rcd);
+		break;
+
+	case QIB_CMD_PIOAVAILUPD:
+		qib_force_pio_avail_update(rcd->dd);
+		break;
+
+	case QIB_CMD_POLL_TYPE:
+		rcd->poll_type = cmd.cmd.poll_type;
+		break;
+
+	case QIB_CMD_ARMLAUNCH_CTRL:
+		rcd->dd->f_set_armlaunch(rcd->dd, cmd.cmd.armlaunch_ctrl);
+		break;
+
+	case QIB_CMD_SDMA_INFLIGHT:
+		ret = qib_sdma_get_inflight(user_sdma_queue_fp(fp),
+					    (u32 __user *) (unsigned long)
+					    cmd.cmd.sdma_inflight);
+		break;
+
+	case QIB_CMD_SDMA_COMPLETE:
+		ret = qib_sdma_get_complete(rcd->ppd,
+					    user_sdma_queue_fp(fp),
+					    (u32 __user *) (unsigned long)
+					    cmd.cmd.sdma_complete);
+		break;
+
+	case QIB_CMD_ACK_EVENT:
+		ret = qib_user_event_ack(rcd, subctxt_fp(fp),
+					 cmd.cmd.event_mask);
+		break;
+	}
+
+	if (ret >= 0)
+		ret = consumed;
+
+bail:
+	return ret;
+}
+
+static ssize_t qib_aio_write(struct kiocb *iocb, const struct iovec *iov,
+			     unsigned long dim, loff_t off)
+{
+	struct qib_filedata *fp = iocb->ki_filp->private_data;
+	struct qib_ctxtdata *rcd = ctxt_fp(iocb->ki_filp);
+	struct qib_user_sdma_queue *pq = fp->pq;
+
+	if (!dim || !pq)
+		return -EINVAL;
+
+	return qib_user_sdma_writev(rcd, pq, iov, dim);
+}
+
+static struct class *qib_class;
+static dev_t qib_dev;
+
+int qib_cdev_init(int minor, const char *name,
+		  const struct file_operations *fops,
+		  struct cdev **cdevp, struct device **devp)
+{
+	const dev_t dev = MKDEV(MAJOR(qib_dev), minor);
+	struct cdev *cdev;
+	struct device *device = NULL;
+	int ret;
+
+	cdev = cdev_alloc();
+	if (!cdev) {
+		printk(KERN_ERR QIB_DRV_NAME
+		       ": Could not allocate cdev for minor %d, %s\n",
+		       minor, name);
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	cdev->owner = THIS_MODULE;
+	cdev->ops = fops;
+	kobject_set_name(&cdev->kobj, name);
+
+	ret = cdev_add(cdev, dev, 1);
+	if (ret < 0) {
+		printk(KERN_ERR QIB_DRV_NAME
+		       ": Could not add cdev for minor %d, %s (err %d)\n",
+		       minor, name, -ret);
+		goto err_cdev;
+	}
+
+	device = device_create(qib_class, NULL, dev, NULL, name);
+	if (!IS_ERR(device))
+		goto done;
+	ret = PTR_ERR(device);
+	device = NULL;
+	printk(KERN_ERR QIB_DRV_NAME ": Could not create "
+	       "device for minor %d, %s (err %d)\n",
+	       minor, name, -ret);
+err_cdev:
+	cdev_del(cdev);
+	cdev = NULL;
+done:
+	*cdevp = cdev;
+	*devp = device;
+	return ret;
+}
+
+void qib_cdev_cleanup(struct cdev **cdevp, struct device **devp)
+{
+	struct device *device = *devp;
+
+	if (device) {
+		device_unregister(device);
+		*devp = NULL;
+	}
+
+	if (*cdevp) {
+		cdev_del(*cdevp);
+		*cdevp = NULL;
+	}
+}
+
+static struct cdev *wildcard_cdev;
+static struct device *wildcard_device;
+
+int __init qib_dev_init(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&qib_dev, 0, QIB_NMINORS, QIB_DRV_NAME);
+	if (ret < 0) {
+		printk(KERN_ERR QIB_DRV_NAME ": Could not allocate "
+		       "chrdev region (err %d)\n", -ret);
+		goto done;
+	}
+
+	qib_class = class_create(THIS_MODULE, "ipath");
+	if (IS_ERR(qib_class)) {
+		ret = PTR_ERR(qib_class);
+		printk(KERN_ERR QIB_DRV_NAME ": Could not create "
+		       "device class (err %d)\n", -ret);
+		unregister_chrdev_region(qib_dev, QIB_NMINORS);
+	}
+
+done:
+	return ret;
+}
+
+void qib_dev_cleanup(void)
+{
+	if (qib_class) {
+		class_destroy(qib_class);
+		qib_class = NULL;
+	}
+
+	unregister_chrdev_region(qib_dev, QIB_NMINORS);
+}
+
+static atomic_t user_count = ATOMIC_INIT(0);
+
+static void qib_user_remove(struct qib_devdata *dd)
+{
+	if (atomic_dec_return(&user_count) == 0)
+		qib_cdev_cleanup(&wildcard_cdev, &wildcard_device);
+
+	qib_cdev_cleanup(&dd->user_cdev, &dd->user_device);
+}
+
+static int qib_user_add(struct qib_devdata *dd)
+{
+	char name[10];
+	int ret;
+
+	if (atomic_inc_return(&user_count) == 1) {
+		ret = qib_cdev_init(0, "ipath", &qib_file_ops,
+				    &wildcard_cdev, &wildcard_device);
+		if (ret)
+			goto done;
+	}
+
+	snprintf(name, sizeof(name), "ipath%d", dd->unit);
+	ret = qib_cdev_init(dd->unit + 1, name, &qib_file_ops,
+			    &dd->user_cdev, &dd->user_device);
+	if (ret)
+		qib_user_remove(dd);
+done:
+	return ret;
+}
+
+/*
+ * Create per-unit files in /dev
+ */
+int qib_device_create(struct qib_devdata *dd)
+{
+	int r, ret;
+
+	r = qib_user_add(dd);
+	ret = qib_diag_add(dd);
+	if (r && !ret)
+		ret = r;
+	return ret;
+}
+
+/*
+ * Remove per-unit files in /dev
+ * void, core kernel returns no errors for this stuff
+ */
+void qib_device_remove(struct qib_devdata *dd)
+{
+	qib_user_remove(dd);
+	qib_diag_remove(dd);
+}