linux-zen-server/drivers/infiniband/hw/hfi1/user_sdma.c

1681 lines
46 KiB
C

// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
/*
* Copyright(c) 2020 - Cornelis Networks, Inc.
* Copyright(c) 2015 - 2018 Intel Corporation.
*/
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/dmapool.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/highmem.h>
#include <linux/io.h>
#include <linux/uio.h>
#include <linux/rbtree.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/kthread.h>
#include <linux/mmu_context.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include "hfi.h"
#include "sdma.h"
#include "user_sdma.h"
#include "verbs.h" /* for the headers */
#include "common.h" /* for struct hfi1_tid_info */
#include "trace.h"
static uint hfi1_sdma_comp_ring_size = 128;
module_param_named(sdma_comp_size, hfi1_sdma_comp_ring_size, uint, S_IRUGO);
MODULE_PARM_DESC(sdma_comp_size, "Size of User SDMA completion ring. Default: 128");
static unsigned initial_pkt_count = 8;
static int user_sdma_send_pkts(struct user_sdma_request *req, u16 maxpkts);
static void user_sdma_txreq_cb(struct sdma_txreq *txreq, int status);
static inline void pq_update(struct hfi1_user_sdma_pkt_q *pq);
static void user_sdma_free_request(struct user_sdma_request *req);
static int check_header_template(struct user_sdma_request *req,
struct hfi1_pkt_header *hdr, u32 lrhlen,
u32 datalen);
static int set_txreq_header(struct user_sdma_request *req,
struct user_sdma_txreq *tx, u32 datalen);
static int set_txreq_header_ahg(struct user_sdma_request *req,
struct user_sdma_txreq *tx, u32 len);
static inline void set_comp_state(struct hfi1_user_sdma_pkt_q *pq,
struct hfi1_user_sdma_comp_q *cq,
u16 idx, enum hfi1_sdma_comp_state state,
int ret);
static inline u32 set_pkt_bth_psn(__be32 bthpsn, u8 expct, u32 frags);
static inline u32 get_lrh_len(struct hfi1_pkt_header, u32 len);
static int defer_packet_queue(
struct sdma_engine *sde,
struct iowait_work *wait,
struct sdma_txreq *txreq,
uint seq,
bool pkts_sent);
static void activate_packet_queue(struct iowait *wait, int reason);
static bool sdma_rb_filter(struct mmu_rb_node *node, unsigned long addr,
unsigned long len);
static int sdma_rb_insert(void *arg, struct mmu_rb_node *mnode);
static int sdma_rb_evict(void *arg, struct mmu_rb_node *mnode,
void *arg2, bool *stop);
static void sdma_rb_remove(void *arg, struct mmu_rb_node *mnode);
static int sdma_rb_invalidate(void *arg, struct mmu_rb_node *mnode);
static struct mmu_rb_ops sdma_rb_ops = {
.filter = sdma_rb_filter,
.insert = sdma_rb_insert,
.evict = sdma_rb_evict,
.remove = sdma_rb_remove,
.invalidate = sdma_rb_invalidate
};
static int add_system_pages_to_sdma_packet(struct user_sdma_request *req,
struct user_sdma_txreq *tx,
struct user_sdma_iovec *iovec,
u32 *pkt_remaining);
static int defer_packet_queue(
struct sdma_engine *sde,
struct iowait_work *wait,
struct sdma_txreq *txreq,
uint seq,
bool pkts_sent)
{
struct hfi1_user_sdma_pkt_q *pq =
container_of(wait->iow, struct hfi1_user_sdma_pkt_q, busy);
write_seqlock(&sde->waitlock);
trace_hfi1_usdma_defer(pq, sde, &pq->busy);
if (sdma_progress(sde, seq, txreq))
goto eagain;
/*
* We are assuming that if the list is enqueued somewhere, it
* is to the dmawait list since that is the only place where
* it is supposed to be enqueued.
*/
xchg(&pq->state, SDMA_PKT_Q_DEFERRED);
if (list_empty(&pq->busy.list)) {
pq->busy.lock = &sde->waitlock;
iowait_get_priority(&pq->busy);
iowait_queue(pkts_sent, &pq->busy, &sde->dmawait);
}
write_sequnlock(&sde->waitlock);
return -EBUSY;
eagain:
write_sequnlock(&sde->waitlock);
return -EAGAIN;
}
static void activate_packet_queue(struct iowait *wait, int reason)
{
struct hfi1_user_sdma_pkt_q *pq =
container_of(wait, struct hfi1_user_sdma_pkt_q, busy);
trace_hfi1_usdma_activate(pq, wait, reason);
xchg(&pq->state, SDMA_PKT_Q_ACTIVE);
wake_up(&wait->wait_dma);
};
int hfi1_user_sdma_alloc_queues(struct hfi1_ctxtdata *uctxt,
struct hfi1_filedata *fd)
{
int ret = -ENOMEM;
char buf[64];
struct hfi1_devdata *dd;
struct hfi1_user_sdma_comp_q *cq;
struct hfi1_user_sdma_pkt_q *pq;
if (!uctxt || !fd)
return -EBADF;
if (!hfi1_sdma_comp_ring_size)
return -EINVAL;
dd = uctxt->dd;
pq = kzalloc(sizeof(*pq), GFP_KERNEL);
if (!pq)
return -ENOMEM;
pq->dd = dd;
pq->ctxt = uctxt->ctxt;
pq->subctxt = fd->subctxt;
pq->n_max_reqs = hfi1_sdma_comp_ring_size;
atomic_set(&pq->n_reqs, 0);
init_waitqueue_head(&pq->wait);
atomic_set(&pq->n_locked, 0);
iowait_init(&pq->busy, 0, NULL, NULL, defer_packet_queue,
activate_packet_queue, NULL, NULL);
pq->reqidx = 0;
pq->reqs = kcalloc(hfi1_sdma_comp_ring_size,
sizeof(*pq->reqs),
GFP_KERNEL);
if (!pq->reqs)
goto pq_reqs_nomem;
pq->req_in_use = bitmap_zalloc(hfi1_sdma_comp_ring_size, GFP_KERNEL);
if (!pq->req_in_use)
goto pq_reqs_no_in_use;
snprintf(buf, 64, "txreq-kmem-cache-%u-%u-%u", dd->unit, uctxt->ctxt,
fd->subctxt);
pq->txreq_cache = kmem_cache_create(buf,
sizeof(struct user_sdma_txreq),
L1_CACHE_BYTES,
SLAB_HWCACHE_ALIGN,
NULL);
if (!pq->txreq_cache) {
dd_dev_err(dd, "[%u] Failed to allocate TxReq cache\n",
uctxt->ctxt);
goto pq_txreq_nomem;
}
cq = kzalloc(sizeof(*cq), GFP_KERNEL);
if (!cq)
goto cq_nomem;
cq->comps = vmalloc_user(PAGE_ALIGN(sizeof(*cq->comps)
* hfi1_sdma_comp_ring_size));
if (!cq->comps)
goto cq_comps_nomem;
cq->nentries = hfi1_sdma_comp_ring_size;
ret = hfi1_mmu_rb_register(pq, &sdma_rb_ops, dd->pport->hfi1_wq,
&pq->handler);
if (ret) {
dd_dev_err(dd, "Failed to register with MMU %d", ret);
goto pq_mmu_fail;
}
rcu_assign_pointer(fd->pq, pq);
fd->cq = cq;
return 0;
pq_mmu_fail:
vfree(cq->comps);
cq_comps_nomem:
kfree(cq);
cq_nomem:
kmem_cache_destroy(pq->txreq_cache);
pq_txreq_nomem:
bitmap_free(pq->req_in_use);
pq_reqs_no_in_use:
kfree(pq->reqs);
pq_reqs_nomem:
kfree(pq);
return ret;
}
static void flush_pq_iowait(struct hfi1_user_sdma_pkt_q *pq)
{
unsigned long flags;
seqlock_t *lock = pq->busy.lock;
if (!lock)
return;
write_seqlock_irqsave(lock, flags);
if (!list_empty(&pq->busy.list)) {
list_del_init(&pq->busy.list);
pq->busy.lock = NULL;
}
write_sequnlock_irqrestore(lock, flags);
}
int hfi1_user_sdma_free_queues(struct hfi1_filedata *fd,
struct hfi1_ctxtdata *uctxt)
{
struct hfi1_user_sdma_pkt_q *pq;
trace_hfi1_sdma_user_free_queues(uctxt->dd, uctxt->ctxt, fd->subctxt);
spin_lock(&fd->pq_rcu_lock);
pq = srcu_dereference_check(fd->pq, &fd->pq_srcu,
lockdep_is_held(&fd->pq_rcu_lock));
if (pq) {
rcu_assign_pointer(fd->pq, NULL);
spin_unlock(&fd->pq_rcu_lock);
synchronize_srcu(&fd->pq_srcu);
/* at this point there can be no more new requests */
if (pq->handler)
hfi1_mmu_rb_unregister(pq->handler);
iowait_sdma_drain(&pq->busy);
/* Wait until all requests have been freed. */
wait_event_interruptible(
pq->wait,
!atomic_read(&pq->n_reqs));
kfree(pq->reqs);
bitmap_free(pq->req_in_use);
kmem_cache_destroy(pq->txreq_cache);
flush_pq_iowait(pq);
kfree(pq);
} else {
spin_unlock(&fd->pq_rcu_lock);
}
if (fd->cq) {
vfree(fd->cq->comps);
kfree(fd->cq);
fd->cq = NULL;
}
return 0;
}
static u8 dlid_to_selector(u16 dlid)
{
static u8 mapping[256];
static int initialized;
static u8 next;
int hash;
if (!initialized) {
memset(mapping, 0xFF, 256);
initialized = 1;
}
hash = ((dlid >> 8) ^ dlid) & 0xFF;
if (mapping[hash] == 0xFF) {
mapping[hash] = next;
next = (next + 1) & 0x7F;
}
return mapping[hash];
}
/**
* hfi1_user_sdma_process_request() - Process and start a user sdma request
* @fd: valid file descriptor
* @iovec: array of io vectors to process
* @dim: overall iovec array size
* @count: number of io vector array entries processed
*/
int hfi1_user_sdma_process_request(struct hfi1_filedata *fd,
struct iovec *iovec, unsigned long dim,
unsigned long *count)
{
int ret = 0, i;
struct hfi1_ctxtdata *uctxt = fd->uctxt;
struct hfi1_user_sdma_pkt_q *pq =
srcu_dereference(fd->pq, &fd->pq_srcu);
struct hfi1_user_sdma_comp_q *cq = fd->cq;
struct hfi1_devdata *dd = pq->dd;
unsigned long idx = 0;
u8 pcount = initial_pkt_count;
struct sdma_req_info info;
struct user_sdma_request *req;
u8 opcode, sc, vl;
u16 pkey;
u32 slid;
u16 dlid;
u32 selector;
if (iovec[idx].iov_len < sizeof(info) + sizeof(req->hdr)) {
hfi1_cdbg(
SDMA,
"[%u:%u:%u] First vector not big enough for header %lu/%lu",
dd->unit, uctxt->ctxt, fd->subctxt,
iovec[idx].iov_len, sizeof(info) + sizeof(req->hdr));
return -EINVAL;
}
ret = copy_from_user(&info, iovec[idx].iov_base, sizeof(info));
if (ret) {
hfi1_cdbg(SDMA, "[%u:%u:%u] Failed to copy info QW (%d)",
dd->unit, uctxt->ctxt, fd->subctxt, ret);
return -EFAULT;
}
trace_hfi1_sdma_user_reqinfo(dd, uctxt->ctxt, fd->subctxt,
(u16 *)&info);
if (info.comp_idx >= hfi1_sdma_comp_ring_size) {
hfi1_cdbg(SDMA,
"[%u:%u:%u:%u] Invalid comp index",
dd->unit, uctxt->ctxt, fd->subctxt, info.comp_idx);
return -EINVAL;
}
/*
* Sanity check the header io vector count. Need at least 1 vector
* (header) and cannot be larger than the actual io vector count.
*/
if (req_iovcnt(info.ctrl) < 1 || req_iovcnt(info.ctrl) > dim) {
hfi1_cdbg(SDMA,
"[%u:%u:%u:%u] Invalid iov count %d, dim %ld",
dd->unit, uctxt->ctxt, fd->subctxt, info.comp_idx,
req_iovcnt(info.ctrl), dim);
return -EINVAL;
}
if (!info.fragsize) {
hfi1_cdbg(SDMA,
"[%u:%u:%u:%u] Request does not specify fragsize",
dd->unit, uctxt->ctxt, fd->subctxt, info.comp_idx);
return -EINVAL;
}
/* Try to claim the request. */
if (test_and_set_bit(info.comp_idx, pq->req_in_use)) {
hfi1_cdbg(SDMA, "[%u:%u:%u] Entry %u is in use",
dd->unit, uctxt->ctxt, fd->subctxt,
info.comp_idx);
return -EBADSLT;
}
/*
* All safety checks have been done and this request has been claimed.
*/
trace_hfi1_sdma_user_process_request(dd, uctxt->ctxt, fd->subctxt,
info.comp_idx);
req = pq->reqs + info.comp_idx;
req->data_iovs = req_iovcnt(info.ctrl) - 1; /* subtract header vector */
req->data_len = 0;
req->pq = pq;
req->cq = cq;
req->ahg_idx = -1;
req->iov_idx = 0;
req->sent = 0;
req->seqnum = 0;
req->seqcomp = 0;
req->seqsubmitted = 0;
req->tids = NULL;
req->has_error = 0;
INIT_LIST_HEAD(&req->txps);
memcpy(&req->info, &info, sizeof(info));
/* The request is initialized, count it */
atomic_inc(&pq->n_reqs);
if (req_opcode(info.ctrl) == EXPECTED) {
/* expected must have a TID info and at least one data vector */
if (req->data_iovs < 2) {
SDMA_DBG(req,
"Not enough vectors for expected request");
ret = -EINVAL;
goto free_req;
}
req->data_iovs--;
}
if (!info.npkts || req->data_iovs > MAX_VECTORS_PER_REQ) {
SDMA_DBG(req, "Too many vectors (%u/%u)", req->data_iovs,
MAX_VECTORS_PER_REQ);
ret = -EINVAL;
goto free_req;
}
/* Copy the header from the user buffer */
ret = copy_from_user(&req->hdr, iovec[idx].iov_base + sizeof(info),
sizeof(req->hdr));
if (ret) {
SDMA_DBG(req, "Failed to copy header template (%d)", ret);
ret = -EFAULT;
goto free_req;
}
/* If Static rate control is not enabled, sanitize the header. */
if (!HFI1_CAP_IS_USET(STATIC_RATE_CTRL))
req->hdr.pbc[2] = 0;
/* Validate the opcode. Do not trust packets from user space blindly. */
opcode = (be32_to_cpu(req->hdr.bth[0]) >> 24) & 0xff;
if ((opcode & USER_OPCODE_CHECK_MASK) !=
USER_OPCODE_CHECK_VAL) {
SDMA_DBG(req, "Invalid opcode (%d)", opcode);
ret = -EINVAL;
goto free_req;
}
/*
* Validate the vl. Do not trust packets from user space blindly.
* VL comes from PBC, SC comes from LRH, and the VL needs to
* match the SC look up.
*/
vl = (le16_to_cpu(req->hdr.pbc[0]) >> 12) & 0xF;
sc = (((be16_to_cpu(req->hdr.lrh[0]) >> 12) & 0xF) |
(((le16_to_cpu(req->hdr.pbc[1]) >> 14) & 0x1) << 4));
if (vl >= dd->pport->vls_operational ||
vl != sc_to_vlt(dd, sc)) {
SDMA_DBG(req, "Invalid SC(%u)/VL(%u)", sc, vl);
ret = -EINVAL;
goto free_req;
}
/* Checking P_KEY for requests from user-space */
pkey = (u16)be32_to_cpu(req->hdr.bth[0]);
slid = be16_to_cpu(req->hdr.lrh[3]);
if (egress_pkey_check(dd->pport, slid, pkey, sc, PKEY_CHECK_INVALID)) {
ret = -EINVAL;
goto free_req;
}
/*
* Also should check the BTH.lnh. If it says the next header is GRH then
* the RXE parsing will be off and will land in the middle of the KDETH
* or miss it entirely.
*/
if ((be16_to_cpu(req->hdr.lrh[0]) & 0x3) == HFI1_LRH_GRH) {
SDMA_DBG(req, "User tried to pass in a GRH");
ret = -EINVAL;
goto free_req;
}
req->koffset = le32_to_cpu(req->hdr.kdeth.swdata[6]);
/*
* Calculate the initial TID offset based on the values of
* KDETH.OFFSET and KDETH.OM that are passed in.
*/
req->tidoffset = KDETH_GET(req->hdr.kdeth.ver_tid_offset, OFFSET) *
(KDETH_GET(req->hdr.kdeth.ver_tid_offset, OM) ?
KDETH_OM_LARGE : KDETH_OM_SMALL);
trace_hfi1_sdma_user_initial_tidoffset(dd, uctxt->ctxt, fd->subctxt,
info.comp_idx, req->tidoffset);
idx++;
/* Save all the IO vector structures */
for (i = 0; i < req->data_iovs; i++) {
req->iovs[i].offset = 0;
INIT_LIST_HEAD(&req->iovs[i].list);
memcpy(&req->iovs[i].iov,
iovec + idx++,
sizeof(req->iovs[i].iov));
if (req->iovs[i].iov.iov_len == 0) {
ret = -EINVAL;
goto free_req;
}
req->data_len += req->iovs[i].iov.iov_len;
}
trace_hfi1_sdma_user_data_length(dd, uctxt->ctxt, fd->subctxt,
info.comp_idx, req->data_len);
if (pcount > req->info.npkts)
pcount = req->info.npkts;
/*
* Copy any TID info
* User space will provide the TID info only when the
* request type is EXPECTED. This is true even if there is
* only one packet in the request and the header is already
* setup. The reason for the singular TID case is that the
* driver needs to perform safety checks.
*/
if (req_opcode(req->info.ctrl) == EXPECTED) {
u16 ntids = iovec[idx].iov_len / sizeof(*req->tids);
u32 *tmp;
if (!ntids || ntids > MAX_TID_PAIR_ENTRIES) {
ret = -EINVAL;
goto free_req;
}
/*
* We have to copy all of the tids because they may vary
* in size and, therefore, the TID count might not be
* equal to the pkt count. However, there is no way to
* tell at this point.
*/
tmp = memdup_user(iovec[idx].iov_base,
ntids * sizeof(*req->tids));
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
SDMA_DBG(req, "Failed to copy %d TIDs (%d)",
ntids, ret);
goto free_req;
}
req->tids = tmp;
req->n_tids = ntids;
req->tididx = 0;
idx++;
}
dlid = be16_to_cpu(req->hdr.lrh[1]);
selector = dlid_to_selector(dlid);
selector += uctxt->ctxt + fd->subctxt;
req->sde = sdma_select_user_engine(dd, selector, vl);
if (!req->sde || !sdma_running(req->sde)) {
ret = -ECOMM;
goto free_req;
}
/* We don't need an AHG entry if the request contains only one packet */
if (req->info.npkts > 1 && HFI1_CAP_IS_USET(SDMA_AHG))
req->ahg_idx = sdma_ahg_alloc(req->sde);
set_comp_state(pq, cq, info.comp_idx, QUEUED, 0);
pq->state = SDMA_PKT_Q_ACTIVE;
/*
* This is a somewhat blocking send implementation.
* The driver will block the caller until all packets of the
* request have been submitted to the SDMA engine. However, it
* will not wait for send completions.
*/
while (req->seqsubmitted != req->info.npkts) {
ret = user_sdma_send_pkts(req, pcount);
if (ret < 0) {
int we_ret;
if (ret != -EBUSY)
goto free_req;
we_ret = wait_event_interruptible_timeout(
pq->busy.wait_dma,
pq->state == SDMA_PKT_Q_ACTIVE,
msecs_to_jiffies(
SDMA_IOWAIT_TIMEOUT));
trace_hfi1_usdma_we(pq, we_ret);
if (we_ret <= 0)
flush_pq_iowait(pq);
}
}
*count += idx;
return 0;
free_req:
/*
* If the submitted seqsubmitted == npkts, the completion routine
* controls the final state. If sequbmitted < npkts, wait for any
* outstanding packets to finish before cleaning up.
*/
if (req->seqsubmitted < req->info.npkts) {
if (req->seqsubmitted)
wait_event(pq->busy.wait_dma,
(req->seqcomp == req->seqsubmitted - 1));
user_sdma_free_request(req);
pq_update(pq);
set_comp_state(pq, cq, info.comp_idx, ERROR, ret);
}
return ret;
}
static inline u32 compute_data_length(struct user_sdma_request *req,
struct user_sdma_txreq *tx)
{
/*
* Determine the proper size of the packet data.
* The size of the data of the first packet is in the header
* template. However, it includes the header and ICRC, which need
* to be subtracted.
* The minimum representable packet data length in a header is 4 bytes,
* therefore, when the data length request is less than 4 bytes, there's
* only one packet, and the packet data length is equal to that of the
* request data length.
* The size of the remaining packets is the minimum of the frag
* size (MTU) or remaining data in the request.
*/
u32 len;
if (!req->seqnum) {
if (req->data_len < sizeof(u32))
len = req->data_len;
else
len = ((be16_to_cpu(req->hdr.lrh[2]) << 2) -
(sizeof(tx->hdr) - 4));
} else if (req_opcode(req->info.ctrl) == EXPECTED) {
u32 tidlen = EXP_TID_GET(req->tids[req->tididx], LEN) *
PAGE_SIZE;
/*
* Get the data length based on the remaining space in the
* TID pair.
*/
len = min(tidlen - req->tidoffset, (u32)req->info.fragsize);
/* If we've filled up the TID pair, move to the next one. */
if (unlikely(!len) && ++req->tididx < req->n_tids &&
req->tids[req->tididx]) {
tidlen = EXP_TID_GET(req->tids[req->tididx],
LEN) * PAGE_SIZE;
req->tidoffset = 0;
len = min_t(u32, tidlen, req->info.fragsize);
}
/*
* Since the TID pairs map entire pages, make sure that we
* are not going to try to send more data that we have
* remaining.
*/
len = min(len, req->data_len - req->sent);
} else {
len = min(req->data_len - req->sent, (u32)req->info.fragsize);
}
trace_hfi1_sdma_user_compute_length(req->pq->dd,
req->pq->ctxt,
req->pq->subctxt,
req->info.comp_idx,
len);
return len;
}
static inline u32 pad_len(u32 len)
{
if (len & (sizeof(u32) - 1))
len += sizeof(u32) - (len & (sizeof(u32) - 1));
return len;
}
static inline u32 get_lrh_len(struct hfi1_pkt_header hdr, u32 len)
{
/* (Size of complete header - size of PBC) + 4B ICRC + data length */
return ((sizeof(hdr) - sizeof(hdr.pbc)) + 4 + len);
}
static int user_sdma_txadd_ahg(struct user_sdma_request *req,
struct user_sdma_txreq *tx,
u32 datalen)
{
int ret;
u16 pbclen = le16_to_cpu(req->hdr.pbc[0]);
u32 lrhlen = get_lrh_len(req->hdr, pad_len(datalen));
struct hfi1_user_sdma_pkt_q *pq = req->pq;
/*
* Copy the request header into the tx header
* because the HW needs a cacheline-aligned
* address.
* This copy can be optimized out if the hdr
* member of user_sdma_request were also
* cacheline aligned.
*/
memcpy(&tx->hdr, &req->hdr, sizeof(tx->hdr));
if (PBC2LRH(pbclen) != lrhlen) {
pbclen = (pbclen & 0xf000) | LRH2PBC(lrhlen);
tx->hdr.pbc[0] = cpu_to_le16(pbclen);
}
ret = check_header_template(req, &tx->hdr, lrhlen, datalen);
if (ret)
return ret;
ret = sdma_txinit_ahg(&tx->txreq, SDMA_TXREQ_F_AHG_COPY,
sizeof(tx->hdr) + datalen, req->ahg_idx,
0, NULL, 0, user_sdma_txreq_cb);
if (ret)
return ret;
ret = sdma_txadd_kvaddr(pq->dd, &tx->txreq, &tx->hdr, sizeof(tx->hdr));
if (ret)
sdma_txclean(pq->dd, &tx->txreq);
return ret;
}
static int user_sdma_send_pkts(struct user_sdma_request *req, u16 maxpkts)
{
int ret = 0;
u16 count;
unsigned npkts = 0;
struct user_sdma_txreq *tx = NULL;
struct hfi1_user_sdma_pkt_q *pq = NULL;
struct user_sdma_iovec *iovec = NULL;
if (!req->pq)
return -EINVAL;
pq = req->pq;
/* If tx completion has reported an error, we are done. */
if (READ_ONCE(req->has_error))
return -EFAULT;
/*
* Check if we might have sent the entire request already
*/
if (unlikely(req->seqnum == req->info.npkts)) {
if (!list_empty(&req->txps))
goto dosend;
return ret;
}
if (!maxpkts || maxpkts > req->info.npkts - req->seqnum)
maxpkts = req->info.npkts - req->seqnum;
while (npkts < maxpkts) {
u32 datalen = 0;
/*
* Check whether any of the completions have come back
* with errors. If so, we are not going to process any
* more packets from this request.
*/
if (READ_ONCE(req->has_error))
return -EFAULT;
tx = kmem_cache_alloc(pq->txreq_cache, GFP_KERNEL);
if (!tx)
return -ENOMEM;
tx->flags = 0;
tx->req = req;
INIT_LIST_HEAD(&tx->list);
/*
* For the last packet set the ACK request
* and disable header suppression.
*/
if (req->seqnum == req->info.npkts - 1)
tx->flags |= (TXREQ_FLAGS_REQ_ACK |
TXREQ_FLAGS_REQ_DISABLE_SH);
/*
* Calculate the payload size - this is min of the fragment
* (MTU) size or the remaining bytes in the request but only
* if we have payload data.
*/
if (req->data_len) {
iovec = &req->iovs[req->iov_idx];
if (READ_ONCE(iovec->offset) == iovec->iov.iov_len) {
if (++req->iov_idx == req->data_iovs) {
ret = -EFAULT;
goto free_tx;
}
iovec = &req->iovs[req->iov_idx];
WARN_ON(iovec->offset);
}
datalen = compute_data_length(req, tx);
/*
* Disable header suppression for the payload <= 8DWS.
* If there is an uncorrectable error in the receive
* data FIFO when the received payload size is less than
* or equal to 8DWS then the RxDmaDataFifoRdUncErr is
* not reported.There is set RHF.EccErr if the header
* is not suppressed.
*/
if (!datalen) {
SDMA_DBG(req,
"Request has data but pkt len is 0");
ret = -EFAULT;
goto free_tx;
} else if (datalen <= 32) {
tx->flags |= TXREQ_FLAGS_REQ_DISABLE_SH;
}
}
if (req->ahg_idx >= 0) {
if (!req->seqnum) {
ret = user_sdma_txadd_ahg(req, tx, datalen);
if (ret)
goto free_tx;
} else {
int changes;
changes = set_txreq_header_ahg(req, tx,
datalen);
if (changes < 0) {
ret = changes;
goto free_tx;
}
}
} else {
ret = sdma_txinit(&tx->txreq, 0, sizeof(req->hdr) +
datalen, user_sdma_txreq_cb);
if (ret)
goto free_tx;
/*
* Modify the header for this packet. This only needs
* to be done if we are not going to use AHG. Otherwise,
* the HW will do it based on the changes we gave it
* during sdma_txinit_ahg().
*/
ret = set_txreq_header(req, tx, datalen);
if (ret)
goto free_txreq;
}
req->koffset += datalen;
if (req_opcode(req->info.ctrl) == EXPECTED)
req->tidoffset += datalen;
req->sent += datalen;
while (datalen) {
ret = add_system_pages_to_sdma_packet(req, tx, iovec,
&datalen);
if (ret)
goto free_txreq;
iovec = &req->iovs[req->iov_idx];
}
list_add_tail(&tx->txreq.list, &req->txps);
/*
* It is important to increment this here as it is used to
* generate the BTH.PSN and, therefore, can't be bulk-updated
* outside of the loop.
*/
tx->seqnum = req->seqnum++;
npkts++;
}
dosend:
ret = sdma_send_txlist(req->sde,
iowait_get_ib_work(&pq->busy),
&req->txps, &count);
req->seqsubmitted += count;
if (req->seqsubmitted == req->info.npkts) {
/*
* The txreq has already been submitted to the HW queue
* so we can free the AHG entry now. Corruption will not
* happen due to the sequential manner in which
* descriptors are processed.
*/
if (req->ahg_idx >= 0)
sdma_ahg_free(req->sde, req->ahg_idx);
}
return ret;
free_txreq:
sdma_txclean(pq->dd, &tx->txreq);
free_tx:
kmem_cache_free(pq->txreq_cache, tx);
return ret;
}
static u32 sdma_cache_evict(struct hfi1_user_sdma_pkt_q *pq, u32 npages)
{
struct evict_data evict_data;
struct mmu_rb_handler *handler = pq->handler;
evict_data.cleared = 0;
evict_data.target = npages;
hfi1_mmu_rb_evict(handler, &evict_data);
return evict_data.cleared;
}
static int check_header_template(struct user_sdma_request *req,
struct hfi1_pkt_header *hdr, u32 lrhlen,
u32 datalen)
{
/*
* Perform safety checks for any type of packet:
* - transfer size is multiple of 64bytes
* - packet length is multiple of 4 bytes
* - packet length is not larger than MTU size
*
* These checks are only done for the first packet of the
* transfer since the header is "given" to us by user space.
* For the remainder of the packets we compute the values.
*/
if (req->info.fragsize % PIO_BLOCK_SIZE || lrhlen & 0x3 ||
lrhlen > get_lrh_len(*hdr, req->info.fragsize))
return -EINVAL;
if (req_opcode(req->info.ctrl) == EXPECTED) {
/*
* The header is checked only on the first packet. Furthermore,
* we ensure that at least one TID entry is copied when the
* request is submitted. Therefore, we don't have to verify that
* tididx points to something sane.
*/
u32 tidval = req->tids[req->tididx],
tidlen = EXP_TID_GET(tidval, LEN) * PAGE_SIZE,
tididx = EXP_TID_GET(tidval, IDX),
tidctrl = EXP_TID_GET(tidval, CTRL),
tidoff;
__le32 kval = hdr->kdeth.ver_tid_offset;
tidoff = KDETH_GET(kval, OFFSET) *
(KDETH_GET(req->hdr.kdeth.ver_tid_offset, OM) ?
KDETH_OM_LARGE : KDETH_OM_SMALL);
/*
* Expected receive packets have the following
* additional checks:
* - offset is not larger than the TID size
* - TIDCtrl values match between header and TID array
* - TID indexes match between header and TID array
*/
if ((tidoff + datalen > tidlen) ||
KDETH_GET(kval, TIDCTRL) != tidctrl ||
KDETH_GET(kval, TID) != tididx)
return -EINVAL;
}
return 0;
}
/*
* Correctly set the BTH.PSN field based on type of
* transfer - eager packets can just increment the PSN but
* expected packets encode generation and sequence in the
* BTH.PSN field so just incrementing will result in errors.
*/
static inline u32 set_pkt_bth_psn(__be32 bthpsn, u8 expct, u32 frags)
{
u32 val = be32_to_cpu(bthpsn),
mask = (HFI1_CAP_IS_KSET(EXTENDED_PSN) ? 0x7fffffffull :
0xffffffull),
psn = val & mask;
if (expct)
psn = (psn & ~HFI1_KDETH_BTH_SEQ_MASK) |
((psn + frags) & HFI1_KDETH_BTH_SEQ_MASK);
else
psn = psn + frags;
return psn & mask;
}
static int set_txreq_header(struct user_sdma_request *req,
struct user_sdma_txreq *tx, u32 datalen)
{
struct hfi1_user_sdma_pkt_q *pq = req->pq;
struct hfi1_pkt_header *hdr = &tx->hdr;
u8 omfactor; /* KDETH.OM */
u16 pbclen;
int ret;
u32 tidval = 0, lrhlen = get_lrh_len(*hdr, pad_len(datalen));
/* Copy the header template to the request before modification */
memcpy(hdr, &req->hdr, sizeof(*hdr));
/*
* Check if the PBC and LRH length are mismatched. If so
* adjust both in the header.
*/
pbclen = le16_to_cpu(hdr->pbc[0]);
if (PBC2LRH(pbclen) != lrhlen) {
pbclen = (pbclen & 0xf000) | LRH2PBC(lrhlen);
hdr->pbc[0] = cpu_to_le16(pbclen);
hdr->lrh[2] = cpu_to_be16(lrhlen >> 2);
/*
* Third packet
* This is the first packet in the sequence that has
* a "static" size that can be used for the rest of
* the packets (besides the last one).
*/
if (unlikely(req->seqnum == 2)) {
/*
* From this point on the lengths in both the
* PBC and LRH are the same until the last
* packet.
* Adjust the template so we don't have to update
* every packet
*/
req->hdr.pbc[0] = hdr->pbc[0];
req->hdr.lrh[2] = hdr->lrh[2];
}
}
/*
* We only have to modify the header if this is not the
* first packet in the request. Otherwise, we use the
* header given to us.
*/
if (unlikely(!req->seqnum)) {
ret = check_header_template(req, hdr, lrhlen, datalen);
if (ret)
return ret;
goto done;
}
hdr->bth[2] = cpu_to_be32(
set_pkt_bth_psn(hdr->bth[2],
(req_opcode(req->info.ctrl) == EXPECTED),
req->seqnum));
/* Set ACK request on last packet */
if (unlikely(tx->flags & TXREQ_FLAGS_REQ_ACK))
hdr->bth[2] |= cpu_to_be32(1UL << 31);
/* Set the new offset */
hdr->kdeth.swdata[6] = cpu_to_le32(req->koffset);
/* Expected packets have to fill in the new TID information */
if (req_opcode(req->info.ctrl) == EXPECTED) {
tidval = req->tids[req->tididx];
/*
* If the offset puts us at the end of the current TID,
* advance everything.
*/
if ((req->tidoffset) == (EXP_TID_GET(tidval, LEN) *
PAGE_SIZE)) {
req->tidoffset = 0;
/*
* Since we don't copy all the TIDs, all at once,
* we have to check again.
*/
if (++req->tididx > req->n_tids - 1 ||
!req->tids[req->tididx]) {
return -EINVAL;
}
tidval = req->tids[req->tididx];
}
omfactor = EXP_TID_GET(tidval, LEN) * PAGE_SIZE >=
KDETH_OM_MAX_SIZE ? KDETH_OM_LARGE_SHIFT :
KDETH_OM_SMALL_SHIFT;
/* Set KDETH.TIDCtrl based on value for this TID. */
KDETH_SET(hdr->kdeth.ver_tid_offset, TIDCTRL,
EXP_TID_GET(tidval, CTRL));
/* Set KDETH.TID based on value for this TID */
KDETH_SET(hdr->kdeth.ver_tid_offset, TID,
EXP_TID_GET(tidval, IDX));
/* Clear KDETH.SH when DISABLE_SH flag is set */
if (unlikely(tx->flags & TXREQ_FLAGS_REQ_DISABLE_SH))
KDETH_SET(hdr->kdeth.ver_tid_offset, SH, 0);
/*
* Set the KDETH.OFFSET and KDETH.OM based on size of
* transfer.
*/
trace_hfi1_sdma_user_tid_info(
pq->dd, pq->ctxt, pq->subctxt, req->info.comp_idx,
req->tidoffset, req->tidoffset >> omfactor,
omfactor != KDETH_OM_SMALL_SHIFT);
KDETH_SET(hdr->kdeth.ver_tid_offset, OFFSET,
req->tidoffset >> omfactor);
KDETH_SET(hdr->kdeth.ver_tid_offset, OM,
omfactor != KDETH_OM_SMALL_SHIFT);
}
done:
trace_hfi1_sdma_user_header(pq->dd, pq->ctxt, pq->subctxt,
req->info.comp_idx, hdr, tidval);
return sdma_txadd_kvaddr(pq->dd, &tx->txreq, hdr, sizeof(*hdr));
}
static int set_txreq_header_ahg(struct user_sdma_request *req,
struct user_sdma_txreq *tx, u32 datalen)
{
u32 ahg[AHG_KDETH_ARRAY_SIZE];
int idx = 0;
u8 omfactor; /* KDETH.OM */
struct hfi1_user_sdma_pkt_q *pq = req->pq;
struct hfi1_pkt_header *hdr = &req->hdr;
u16 pbclen = le16_to_cpu(hdr->pbc[0]);
u32 val32, tidval = 0, lrhlen = get_lrh_len(*hdr, pad_len(datalen));
size_t array_size = ARRAY_SIZE(ahg);
if (PBC2LRH(pbclen) != lrhlen) {
/* PBC.PbcLengthDWs */
idx = ahg_header_set(ahg, idx, array_size, 0, 0, 12,
(__force u16)cpu_to_le16(LRH2PBC(lrhlen)));
if (idx < 0)
return idx;
/* LRH.PktLen (we need the full 16 bits due to byte swap) */
idx = ahg_header_set(ahg, idx, array_size, 3, 0, 16,
(__force u16)cpu_to_be16(lrhlen >> 2));
if (idx < 0)
return idx;
}
/*
* Do the common updates
*/
/* BTH.PSN and BTH.A */
val32 = (be32_to_cpu(hdr->bth[2]) + req->seqnum) &
(HFI1_CAP_IS_KSET(EXTENDED_PSN) ? 0x7fffffff : 0xffffff);
if (unlikely(tx->flags & TXREQ_FLAGS_REQ_ACK))
val32 |= 1UL << 31;
idx = ahg_header_set(ahg, idx, array_size, 6, 0, 16,
(__force u16)cpu_to_be16(val32 >> 16));
if (idx < 0)
return idx;
idx = ahg_header_set(ahg, idx, array_size, 6, 16, 16,
(__force u16)cpu_to_be16(val32 & 0xffff));
if (idx < 0)
return idx;
/* KDETH.Offset */
idx = ahg_header_set(ahg, idx, array_size, 15, 0, 16,
(__force u16)cpu_to_le16(req->koffset & 0xffff));
if (idx < 0)
return idx;
idx = ahg_header_set(ahg, idx, array_size, 15, 16, 16,
(__force u16)cpu_to_le16(req->koffset >> 16));
if (idx < 0)
return idx;
if (req_opcode(req->info.ctrl) == EXPECTED) {
__le16 val;
tidval = req->tids[req->tididx];
/*
* If the offset puts us at the end of the current TID,
* advance everything.
*/
if ((req->tidoffset) == (EXP_TID_GET(tidval, LEN) *
PAGE_SIZE)) {
req->tidoffset = 0;
/*
* Since we don't copy all the TIDs, all at once,
* we have to check again.
*/
if (++req->tididx > req->n_tids - 1 ||
!req->tids[req->tididx])
return -EINVAL;
tidval = req->tids[req->tididx];
}
omfactor = ((EXP_TID_GET(tidval, LEN) *
PAGE_SIZE) >=
KDETH_OM_MAX_SIZE) ? KDETH_OM_LARGE_SHIFT :
KDETH_OM_SMALL_SHIFT;
/* KDETH.OM and KDETH.OFFSET (TID) */
idx = ahg_header_set(
ahg, idx, array_size, 7, 0, 16,
((!!(omfactor - KDETH_OM_SMALL_SHIFT)) << 15 |
((req->tidoffset >> omfactor)
& 0x7fff)));
if (idx < 0)
return idx;
/* KDETH.TIDCtrl, KDETH.TID, KDETH.Intr, KDETH.SH */
val = cpu_to_le16(((EXP_TID_GET(tidval, CTRL) & 0x3) << 10) |
(EXP_TID_GET(tidval, IDX) & 0x3ff));
if (unlikely(tx->flags & TXREQ_FLAGS_REQ_DISABLE_SH)) {
val |= cpu_to_le16((KDETH_GET(hdr->kdeth.ver_tid_offset,
INTR) <<
AHG_KDETH_INTR_SHIFT));
} else {
val |= KDETH_GET(hdr->kdeth.ver_tid_offset, SH) ?
cpu_to_le16(0x1 << AHG_KDETH_SH_SHIFT) :
cpu_to_le16((KDETH_GET(hdr->kdeth.ver_tid_offset,
INTR) <<
AHG_KDETH_INTR_SHIFT));
}
idx = ahg_header_set(ahg, idx, array_size,
7, 16, 14, (__force u16)val);
if (idx < 0)
return idx;
}
trace_hfi1_sdma_user_header_ahg(pq->dd, pq->ctxt, pq->subctxt,
req->info.comp_idx, req->sde->this_idx,
req->ahg_idx, ahg, idx, tidval);
sdma_txinit_ahg(&tx->txreq,
SDMA_TXREQ_F_USE_AHG,
datalen, req->ahg_idx, idx,
ahg, sizeof(req->hdr),
user_sdma_txreq_cb);
return idx;
}
/**
* user_sdma_txreq_cb() - SDMA tx request completion callback.
* @txreq: valid sdma tx request
* @status: success/failure of request
*
* Called when the SDMA progress state machine gets notification that
* the SDMA descriptors for this tx request have been processed by the
* DMA engine. Called in interrupt context.
* Only do work on completed sequences.
*/
static void user_sdma_txreq_cb(struct sdma_txreq *txreq, int status)
{
struct user_sdma_txreq *tx =
container_of(txreq, struct user_sdma_txreq, txreq);
struct user_sdma_request *req;
struct hfi1_user_sdma_pkt_q *pq;
struct hfi1_user_sdma_comp_q *cq;
enum hfi1_sdma_comp_state state = COMPLETE;
if (!tx->req)
return;
req = tx->req;
pq = req->pq;
cq = req->cq;
if (status != SDMA_TXREQ_S_OK) {
SDMA_DBG(req, "SDMA completion with error %d",
status);
WRITE_ONCE(req->has_error, 1);
state = ERROR;
}
req->seqcomp = tx->seqnum;
kmem_cache_free(pq->txreq_cache, tx);
/* sequence isn't complete? We are done */
if (req->seqcomp != req->info.npkts - 1)
return;
user_sdma_free_request(req);
set_comp_state(pq, cq, req->info.comp_idx, state, status);
pq_update(pq);
}
static inline void pq_update(struct hfi1_user_sdma_pkt_q *pq)
{
if (atomic_dec_and_test(&pq->n_reqs))
wake_up(&pq->wait);
}
static void user_sdma_free_request(struct user_sdma_request *req)
{
if (!list_empty(&req->txps)) {
struct sdma_txreq *t, *p;
list_for_each_entry_safe(t, p, &req->txps, list) {
struct user_sdma_txreq *tx =
container_of(t, struct user_sdma_txreq, txreq);
list_del_init(&t->list);
sdma_txclean(req->pq->dd, t);
kmem_cache_free(req->pq->txreq_cache, tx);
}
}
kfree(req->tids);
clear_bit(req->info.comp_idx, req->pq->req_in_use);
}
static inline void set_comp_state(struct hfi1_user_sdma_pkt_q *pq,
struct hfi1_user_sdma_comp_q *cq,
u16 idx, enum hfi1_sdma_comp_state state,
int ret)
{
if (state == ERROR)
cq->comps[idx].errcode = -ret;
smp_wmb(); /* make sure errcode is visible first */
cq->comps[idx].status = state;
trace_hfi1_sdma_user_completion(pq->dd, pq->ctxt, pq->subctxt,
idx, state, ret);
}
static void unpin_vector_pages(struct mm_struct *mm, struct page **pages,
unsigned int start, unsigned int npages)
{
hfi1_release_user_pages(mm, pages + start, npages, false);
kfree(pages);
}
static void free_system_node(struct sdma_mmu_node *node)
{
if (node->npages) {
unpin_vector_pages(mm_from_sdma_node(node), node->pages, 0,
node->npages);
atomic_sub(node->npages, &node->pq->n_locked);
}
kfree(node);
}
static inline void acquire_node(struct sdma_mmu_node *node)
{
atomic_inc(&node->refcount);
WARN_ON(atomic_read(&node->refcount) < 0);
}
static inline void release_node(struct mmu_rb_handler *handler,
struct sdma_mmu_node *node)
{
atomic_dec(&node->refcount);
WARN_ON(atomic_read(&node->refcount) < 0);
}
static struct sdma_mmu_node *find_system_node(struct mmu_rb_handler *handler,
unsigned long start,
unsigned long end)
{
struct mmu_rb_node *rb_node;
struct sdma_mmu_node *node;
unsigned long flags;
spin_lock_irqsave(&handler->lock, flags);
rb_node = hfi1_mmu_rb_get_first(handler, start, (end - start));
if (!rb_node) {
spin_unlock_irqrestore(&handler->lock, flags);
return NULL;
}
node = container_of(rb_node, struct sdma_mmu_node, rb);
acquire_node(node);
spin_unlock_irqrestore(&handler->lock, flags);
return node;
}
static int pin_system_pages(struct user_sdma_request *req,
uintptr_t start_address, size_t length,
struct sdma_mmu_node *node, int npages)
{
struct hfi1_user_sdma_pkt_q *pq = req->pq;
int pinned, cleared;
struct page **pages;
pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
if (!pages)
return -ENOMEM;
retry:
if (!hfi1_can_pin_pages(pq->dd, current->mm, atomic_read(&pq->n_locked),
npages)) {
SDMA_DBG(req, "Evicting: nlocked %u npages %u",
atomic_read(&pq->n_locked), npages);
cleared = sdma_cache_evict(pq, npages);
if (cleared >= npages)
goto retry;
}
SDMA_DBG(req, "Acquire user pages start_address %lx node->npages %u npages %u",
start_address, node->npages, npages);
pinned = hfi1_acquire_user_pages(current->mm, start_address, npages, 0,
pages);
if (pinned < 0) {
kfree(pages);
SDMA_DBG(req, "pinned %d", pinned);
return pinned;
}
if (pinned != npages) {
unpin_vector_pages(current->mm, pages, node->npages, pinned);
SDMA_DBG(req, "npages %u pinned %d", npages, pinned);
return -EFAULT;
}
node->rb.addr = start_address;
node->rb.len = length;
node->pages = pages;
node->npages = npages;
atomic_add(pinned, &pq->n_locked);
SDMA_DBG(req, "done. pinned %d", pinned);
return 0;
}
static int add_system_pinning(struct user_sdma_request *req,
struct sdma_mmu_node **node_p,
unsigned long start, unsigned long len)
{
struct hfi1_user_sdma_pkt_q *pq = req->pq;
struct sdma_mmu_node *node;
int ret;
node = kzalloc(sizeof(*node), GFP_KERNEL);
if (!node)
return -ENOMEM;
node->pq = pq;
ret = pin_system_pages(req, start, len, node, PFN_DOWN(len));
if (ret == 0) {
ret = hfi1_mmu_rb_insert(pq->handler, &node->rb);
if (ret)
free_system_node(node);
else
*node_p = node;
return ret;
}
kfree(node);
return ret;
}
static int get_system_cache_entry(struct user_sdma_request *req,
struct sdma_mmu_node **node_p,
size_t req_start, size_t req_len)
{
struct hfi1_user_sdma_pkt_q *pq = req->pq;
u64 start = ALIGN_DOWN(req_start, PAGE_SIZE);
u64 end = PFN_ALIGN(req_start + req_len);
struct mmu_rb_handler *handler = pq->handler;
int ret;
if ((end - start) == 0) {
SDMA_DBG(req,
"Request for empty cache entry req_start %lx req_len %lx start %llx end %llx",
req_start, req_len, start, end);
return -EINVAL;
}
SDMA_DBG(req, "req_start %lx req_len %lu", req_start, req_len);
while (1) {
struct sdma_mmu_node *node =
find_system_node(handler, start, end);
u64 prepend_len = 0;
SDMA_DBG(req, "node %p start %llx end %llu", node, start, end);
if (!node) {
ret = add_system_pinning(req, node_p, start,
end - start);
if (ret == -EEXIST) {
/*
* Another execution context has inserted a
* conficting entry first.
*/
continue;
}
return ret;
}
if (node->rb.addr <= start) {
/*
* This entry covers at least part of the region. If it doesn't extend
* to the end, then this will be called again for the next segment.
*/
*node_p = node;
return 0;
}
SDMA_DBG(req, "prepend: node->rb.addr %lx, node->refcount %d",
node->rb.addr, atomic_read(&node->refcount));
prepend_len = node->rb.addr - start;
/*
* This node will not be returned, instead a new node
* will be. So release the reference.
*/
release_node(handler, node);
/* Prepend a node to cover the beginning of the allocation */
ret = add_system_pinning(req, node_p, start, prepend_len);
if (ret == -EEXIST) {
/* Another execution context has inserted a conficting entry first. */
continue;
}
return ret;
}
}
static int add_mapping_to_sdma_packet(struct user_sdma_request *req,
struct user_sdma_txreq *tx,
struct sdma_mmu_node *cache_entry,
size_t start,
size_t from_this_cache_entry)
{
struct hfi1_user_sdma_pkt_q *pq = req->pq;
unsigned int page_offset;
unsigned int from_this_page;
size_t page_index;
void *ctx;
int ret;
/*
* Because the cache may be more fragmented than the memory that is being accessed,
* it's not strictly necessary to have a descriptor per cache entry.
*/
while (from_this_cache_entry) {
page_index = PFN_DOWN(start - cache_entry->rb.addr);
if (page_index >= cache_entry->npages) {
SDMA_DBG(req,
"Request for page_index %zu >= cache_entry->npages %u",
page_index, cache_entry->npages);
return -EINVAL;
}
page_offset = start - ALIGN_DOWN(start, PAGE_SIZE);
from_this_page = PAGE_SIZE - page_offset;
if (from_this_page < from_this_cache_entry) {
ctx = NULL;
} else {
/*
* In the case they are equal the next line has no practical effect,
* but it's better to do a register to register copy than a conditional
* branch.
*/
from_this_page = from_this_cache_entry;
ctx = cache_entry;
}
ret = sdma_txadd_page(pq->dd, ctx, &tx->txreq,
cache_entry->pages[page_index],
page_offset, from_this_page);
if (ret) {
/*
* When there's a failure, the entire request is freed by
* user_sdma_send_pkts().
*/
SDMA_DBG(req,
"sdma_txadd_page failed %d page_index %lu page_offset %u from_this_page %u",
ret, page_index, page_offset, from_this_page);
return ret;
}
start += from_this_page;
from_this_cache_entry -= from_this_page;
}
return 0;
}
static int add_system_iovec_to_sdma_packet(struct user_sdma_request *req,
struct user_sdma_txreq *tx,
struct user_sdma_iovec *iovec,
size_t from_this_iovec)
{
struct mmu_rb_handler *handler = req->pq->handler;
while (from_this_iovec > 0) {
struct sdma_mmu_node *cache_entry;
size_t from_this_cache_entry;
size_t start;
int ret;
start = (uintptr_t)iovec->iov.iov_base + iovec->offset;
ret = get_system_cache_entry(req, &cache_entry, start,
from_this_iovec);
if (ret) {
SDMA_DBG(req, "pin system segment failed %d", ret);
return ret;
}
from_this_cache_entry = cache_entry->rb.len - (start - cache_entry->rb.addr);
if (from_this_cache_entry > from_this_iovec)
from_this_cache_entry = from_this_iovec;
ret = add_mapping_to_sdma_packet(req, tx, cache_entry, start,
from_this_cache_entry);
if (ret) {
/*
* We're guaranteed that there will be no descriptor
* completion callback that releases this node
* because only the last descriptor referencing it
* has a context attached, and a failure means the
* last descriptor was never added.
*/
release_node(handler, cache_entry);
SDMA_DBG(req, "add system segment failed %d", ret);
return ret;
}
iovec->offset += from_this_cache_entry;
from_this_iovec -= from_this_cache_entry;
}
return 0;
}
static int add_system_pages_to_sdma_packet(struct user_sdma_request *req,
struct user_sdma_txreq *tx,
struct user_sdma_iovec *iovec,
u32 *pkt_data_remaining)
{
size_t remaining_to_add = *pkt_data_remaining;
/*
* Walk through iovec entries, ensure the associated pages
* are pinned and mapped, add data to the packet until no more
* data remains to be added.
*/
while (remaining_to_add > 0) {
struct user_sdma_iovec *cur_iovec;
size_t from_this_iovec;
int ret;
cur_iovec = iovec;
from_this_iovec = iovec->iov.iov_len - iovec->offset;
if (from_this_iovec > remaining_to_add) {
from_this_iovec = remaining_to_add;
} else {
/* The current iovec entry will be consumed by this pass. */
req->iov_idx++;
iovec++;
}
ret = add_system_iovec_to_sdma_packet(req, tx, cur_iovec,
from_this_iovec);
if (ret)
return ret;
remaining_to_add -= from_this_iovec;
}
*pkt_data_remaining = remaining_to_add;
return 0;
}
void system_descriptor_complete(struct hfi1_devdata *dd,
struct sdma_desc *descp)
{
switch (sdma_mapping_type(descp)) {
case SDMA_MAP_SINGLE:
dma_unmap_single(&dd->pcidev->dev, sdma_mapping_addr(descp),
sdma_mapping_len(descp), DMA_TO_DEVICE);
break;
case SDMA_MAP_PAGE:
dma_unmap_page(&dd->pcidev->dev, sdma_mapping_addr(descp),
sdma_mapping_len(descp), DMA_TO_DEVICE);
break;
}
if (descp->pinning_ctx) {
struct sdma_mmu_node *node = descp->pinning_ctx;
release_node(node->rb.handler, node);
}
}
static bool sdma_rb_filter(struct mmu_rb_node *node, unsigned long addr,
unsigned long len)
{
return (bool)(node->addr == addr);
}
static int sdma_rb_insert(void *arg, struct mmu_rb_node *mnode)
{
struct sdma_mmu_node *node =
container_of(mnode, struct sdma_mmu_node, rb);
atomic_inc(&node->refcount);
return 0;
}
/*
* Return 1 to remove the node from the rb tree and call the remove op.
*
* Called with the rb tree lock held.
*/
static int sdma_rb_evict(void *arg, struct mmu_rb_node *mnode,
void *evict_arg, bool *stop)
{
struct sdma_mmu_node *node =
container_of(mnode, struct sdma_mmu_node, rb);
struct evict_data *evict_data = evict_arg;
/* is this node still being used? */
if (atomic_read(&node->refcount))
return 0; /* keep this node */
/* this node will be evicted, add its pages to our count */
evict_data->cleared += node->npages;
/* have enough pages been cleared? */
if (evict_data->cleared >= evict_data->target)
*stop = true;
return 1; /* remove this node */
}
static void sdma_rb_remove(void *arg, struct mmu_rb_node *mnode)
{
struct sdma_mmu_node *node =
container_of(mnode, struct sdma_mmu_node, rb);
free_system_node(node);
}
static int sdma_rb_invalidate(void *arg, struct mmu_rb_node *mnode)
{
struct sdma_mmu_node *node =
container_of(mnode, struct sdma_mmu_node, rb);
if (!atomic_read(&node->refcount))
return 1;
return 0;
}