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|
/*
* Copyright(c) 2015-2018 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 <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 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,
struct tid_group **grp);
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,
};
/*
* 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;
spin_lock_init(&fd->tid_lock);
spin_lock_init(&fd->invalid_lock);
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;
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);
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;
if (mapped) {
pci_unmap_single(dd->pcidev, node->dma_addr,
node->npages * PAGE_SIZE, PCI_DMA_FROMDEVICE);
pages = &node->pages[idx];
} else {
pages = &tidbuf->pages[idx];
}
hfi1_release_user_pages(fd->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;
unsigned long vaddr = tidbuf->vaddr;
struct page **pages = NULL;
struct hfi1_devdata *dd = fd->uctxt->dd;
/* Get the number of pages the user buffer spans */
npages = num_user_pages(vaddr, tidbuf->length);
if (!npages)
return -EINVAL;
if (npages > fd->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((void __user *)vaddr,
npages * PAGE_SIZE)) {
dd_dev_err(dd, "Fail vaddr %p, %u pages, !access_ok\n",
(void *)vaddr, npages);
return -EFAULT;
}
/* 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, fd->mm, fd->tid_n_pinned, npages)) {
kfree(pages);
return -ENOMEM;
}
pinned = hfi1_acquire_user_pages(fd->mm, vaddr, npages, true, pages);
if (pinned <= 0) {
kfree(pages);
return pinned;
}
tidbuf->pages = pages;
tidbuf->npages = npages;
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;
if (!PAGE_ALIGNED(tinfo->vaddr))
return -EINVAL;
tidbuf = kzalloc(sizeof(*tidbuf), GFP_KERNEL);
if (!tidbuf)
return -ENOMEM;
tidbuf->vaddr = tinfo->vaddr;
tidbuf->length = tinfo->length;
tidbuf->psets = kcalloc(uctxt->expected_count, sizeof(*tidbuf->psets),
GFP_KERNEL);
if (!tidbuf->psets) {
kfree(tidbuf);
return -ENOMEM;
}
pinned = pin_rcv_pages(fd, tidbuf);
if (pinned <= 0) {
kfree(tidbuf->psets);
kfree(tidbuf);
return pinned;
}
/* Find sets of physically contiguous pages */
tidbuf->n_psets = find_phys_blocks(tidbuf, pinned);
/*
* 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 + tidbuf->n_psets > fd->tid_limit)
pageset_count = fd->tid_limit - fd->tid_used;
else
pageset_count = tidbuf->n_psets;
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_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);
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(u64_to_user_ptr(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(fd, 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)
unpin_rcv_pages(fd, tidbuf, NULL, mapped_pages,
(pinned - mapped_pages), false);
bail:
kfree(tidbuf->psets);
kfree(tidlist);
kfree(tidbuf->pages);
kfree(tidbuf);
return ret > 0 ? 0 : 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], 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_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(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->fdata = fd;
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 (fd->use_mn) {
ret = mmu_interval_notifier_insert(
&node->notifier, fd->mm,
tbuf->vaddr + (pageidx * PAGE_SIZE), npages * PAGE_SIZE,
&tid_mn_ops);
if (ret)
goto out_unmap;
/*
* FIXME: This is in the wrong order, the notifier should be
* established before the pages are pinned by pin_rcv_pages.
*/
mmu_interval_read_begin(&node->notifier);
}
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);
pci_unmap_single(dd->pcidev, phys, npages * PAGE_SIZE,
PCI_DMA_FROMDEVICE);
kfree(node);
return -EFAULT;
}
static int unprogram_rcvarray(struct hfi1_filedata *fd, u32 tidinfo,
struct tid_group **grp)
{
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 (grp)
*grp = node->grp;
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;
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 we unpin the
* pages.
*/
hfi1_put_tid(dd, node->rcventry, PT_INVALID_FLUSH, 0, 0);
unpin_rcv_pages(fd, NULL, node, 0, node->npages, true);
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;
trace_hfi1_exp_tid_inval(uctxt->ctxt, fdata->subctxt,
node->notifier.interval_tree.start,
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_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 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);
}
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