OpenCloudOS-Kernel/net/sunrpc/xprtrdma/frwr_ops.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2015, 2017 Oracle. All rights reserved.
* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
*/
/* Lightweight memory registration using Fast Registration Work
* Requests (FRWR).
*
* FRWR features ordered asynchronous registration and invalidation
* of arbitrarily-sized memory regions. This is the fastest and safest
* but most complex memory registration mode.
*/
/* Normal operation
*
* A Memory Region is prepared for RDMA Read or Write using a FAST_REG
* Work Request (frwr_map). When the RDMA operation is finished, this
* Memory Region is invalidated using a LOCAL_INV Work Request
* (frwr_unmap_async and frwr_unmap_sync).
*
* Typically FAST_REG Work Requests are not signaled, and neither are
* RDMA Send Work Requests (with the exception of signaling occasionally
* to prevent provider work queue overflows). This greatly reduces HCA
* interrupt workload.
*/
/* Transport recovery
*
* frwr_map and frwr_unmap_* cannot run at the same time the transport
* connect worker is running. The connect worker holds the transport
* send lock, just as ->send_request does. This prevents frwr_map and
* the connect worker from running concurrently. When a connection is
* closed, the Receive completion queue is drained before the allowing
* the connect worker to get control. This prevents frwr_unmap and the
* connect worker from running concurrently.
*
* When the underlying transport disconnects, MRs that are in flight
* are flushed and are likely unusable. Thus all flushed MRs are
* destroyed. New MRs are created on demand.
*/
#include <linux/sunrpc/rpc_rdma.h>
#include <linux/sunrpc/svc_rdma.h>
#include "xprt_rdma.h"
#include <trace/events/rpcrdma.h>
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_TRANS
#endif
/**
* frwr_is_supported - Check if device supports FRWR
* @device: interface adapter to check
*
* Returns true if device supports FRWR, otherwise false
*/
bool frwr_is_supported(struct ib_device *device)
{
struct ib_device_attr *attrs = &device->attrs;
if (!(attrs->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
goto out_not_supported;
if (attrs->max_fast_reg_page_list_len == 0)
goto out_not_supported;
return true;
out_not_supported:
pr_info("rpcrdma: 'frwr' mode is not supported by device %s\n",
device->name);
return false;
}
/**
* frwr_release_mr - Destroy one MR
* @mr: MR allocated by frwr_init_mr
*
*/
void frwr_release_mr(struct rpcrdma_mr *mr)
{
int rc;
rc = ib_dereg_mr(mr->frwr.fr_mr);
if (rc)
trace_xprtrdma_frwr_dereg(mr, rc);
kfree(mr->mr_sg);
kfree(mr);
}
static void frwr_mr_recycle(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr *mr)
{
trace_xprtrdma_mr_recycle(mr);
if (mr->mr_dir != DMA_NONE) {
trace_xprtrdma_mr_unmap(mr);
ib_dma_unmap_sg(r_xprt->rx_ia.ri_id->device,
mr->mr_sg, mr->mr_nents, mr->mr_dir);
mr->mr_dir = DMA_NONE;
}
spin_lock(&r_xprt->rx_buf.rb_lock);
list_del(&mr->mr_all);
r_xprt->rx_stats.mrs_recycled++;
spin_unlock(&r_xprt->rx_buf.rb_lock);
frwr_release_mr(mr);
}
/* MRs are dynamically allocated, so simply clean up and release the MR.
* A replacement MR will subsequently be allocated on demand.
*/
static void
frwr_mr_recycle_worker(struct work_struct *work)
{
struct rpcrdma_mr *mr = container_of(work, struct rpcrdma_mr,
mr_recycle);
frwr_mr_recycle(mr->mr_xprt, mr);
}
/* frwr_recycle - Discard MRs
* @req: request to reset
*
* Used after a reconnect. These MRs could be in flight, we can't
* tell. Safe thing to do is release them.
*/
void frwr_recycle(struct rpcrdma_req *req)
{
struct rpcrdma_mr *mr;
while ((mr = rpcrdma_mr_pop(&req->rl_registered)))
frwr_mr_recycle(mr->mr_xprt, mr);
}
/* frwr_reset - Place MRs back on the free list
* @req: request to reset
*
* Used after a failed marshal. For FRWR, this means the MRs
* don't have to be fully released and recreated.
*
* NB: This is safe only as long as none of @req's MRs are
* involved with an ongoing asynchronous FAST_REG or LOCAL_INV
* Work Request.
*/
void frwr_reset(struct rpcrdma_req *req)
{
struct rpcrdma_mr *mr;
while ((mr = rpcrdma_mr_pop(&req->rl_registered)))
rpcrdma_mr_put(mr);
}
/**
* frwr_init_mr - Initialize one MR
* @ia: interface adapter
* @mr: generic MR to prepare for FRWR
*
* Returns zero if successful. Otherwise a negative errno
* is returned.
*/
int frwr_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr)
{
unsigned int depth = ia->ri_max_frwr_depth;
struct scatterlist *sg;
struct ib_mr *frmr;
int rc;
/* NB: ib_alloc_mr and device drivers typically allocate
* memory with GFP_KERNEL.
*/
frmr = ib_alloc_mr(ia->ri_pd, ia->ri_mrtype, depth);
if (IS_ERR(frmr))
goto out_mr_err;
sg = kcalloc(depth, sizeof(*sg), GFP_NOFS);
if (!sg)
goto out_list_err;
mr->frwr.fr_mr = frmr;
mr->mr_dir = DMA_NONE;
INIT_LIST_HEAD(&mr->mr_list);
INIT_WORK(&mr->mr_recycle, frwr_mr_recycle_worker);
init_completion(&mr->frwr.fr_linv_done);
sg_init_table(sg, depth);
mr->mr_sg = sg;
return 0;
out_mr_err:
rc = PTR_ERR(frmr);
trace_xprtrdma_frwr_alloc(mr, rc);
return rc;
out_list_err:
ib_dereg_mr(frmr);
return -ENOMEM;
}
/**
* frwr_open - Prepare an endpoint for use with FRWR
* @ia: interface adapter this endpoint will use
* @ep: endpoint to prepare
*
* On success, sets:
* ep->rep_attr.cap.max_send_wr
* ep->rep_attr.cap.max_recv_wr
* ep->rep_max_requests
* ia->ri_max_segs
*
* And these FRWR-related fields:
* ia->ri_max_frwr_depth
* ia->ri_mrtype
*
* On failure, a negative errno is returned.
*/
int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep)
{
struct ib_device_attr *attrs = &ia->ri_id->device->attrs;
int max_qp_wr, depth, delta;
ia->ri_mrtype = IB_MR_TYPE_MEM_REG;
if (attrs->device_cap_flags & IB_DEVICE_SG_GAPS_REG)
ia->ri_mrtype = IB_MR_TYPE_SG_GAPS;
/* Quirk: Some devices advertise a large max_fast_reg_page_list_len
* capability, but perform optimally when the MRs are not larger
* than a page.
*/
if (attrs->max_sge_rd > 1)
ia->ri_max_frwr_depth = attrs->max_sge_rd;
else
ia->ri_max_frwr_depth = attrs->max_fast_reg_page_list_len;
if (ia->ri_max_frwr_depth > RPCRDMA_MAX_DATA_SEGS)
ia->ri_max_frwr_depth = RPCRDMA_MAX_DATA_SEGS;
dprintk("RPC: %s: max FR page list depth = %u\n",
__func__, ia->ri_max_frwr_depth);
/* Add room for frwr register and invalidate WRs.
* 1. FRWR reg WR for head
* 2. FRWR invalidate WR for head
* 3. N FRWR reg WRs for pagelist
* 4. N FRWR invalidate WRs for pagelist
* 5. FRWR reg WR for tail
* 6. FRWR invalidate WR for tail
* 7. The RDMA_SEND WR
*/
depth = 7;
/* Calculate N if the device max FRWR depth is smaller than
* RPCRDMA_MAX_DATA_SEGS.
*/
if (ia->ri_max_frwr_depth < RPCRDMA_MAX_DATA_SEGS) {
delta = RPCRDMA_MAX_DATA_SEGS - ia->ri_max_frwr_depth;
do {
depth += 2; /* FRWR reg + invalidate */
delta -= ia->ri_max_frwr_depth;
} while (delta > 0);
}
max_qp_wr = ia->ri_id->device->attrs.max_qp_wr;
max_qp_wr -= RPCRDMA_BACKWARD_WRS;
max_qp_wr -= 1;
if (max_qp_wr < RPCRDMA_MIN_SLOT_TABLE)
return -ENOMEM;
if (ep->rep_max_requests > max_qp_wr)
ep->rep_max_requests = max_qp_wr;
ep->rep_attr.cap.max_send_wr = ep->rep_max_requests * depth;
if (ep->rep_attr.cap.max_send_wr > max_qp_wr) {
ep->rep_max_requests = max_qp_wr / depth;
if (!ep->rep_max_requests)
return -EINVAL;
ep->rep_attr.cap.max_send_wr = ep->rep_max_requests * depth;
}
ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS;
ep->rep_attr.cap.max_send_wr += 1; /* for ib_drain_sq */
ep->rep_attr.cap.max_recv_wr = ep->rep_max_requests;
ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;
ep->rep_attr.cap.max_recv_wr += 1; /* for ib_drain_rq */
ia->ri_max_segs =
DIV_ROUND_UP(RPCRDMA_MAX_DATA_SEGS, ia->ri_max_frwr_depth);
/* Reply chunks require segments for head and tail buffers */
ia->ri_max_segs += 2;
if (ia->ri_max_segs > RPCRDMA_MAX_HDR_SEGS)
ia->ri_max_segs = RPCRDMA_MAX_HDR_SEGS;
return 0;
}
/**
* frwr_maxpages - Compute size of largest payload
* @r_xprt: transport
*
* Returns maximum size of an RPC message, in pages.
*
* FRWR mode conveys a list of pages per chunk segment. The
* maximum length of that list is the FRWR page list depth.
*/
size_t frwr_maxpages(struct rpcrdma_xprt *r_xprt)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
(ia->ri_max_segs - 2) * ia->ri_max_frwr_depth);
}
/**
* frwr_map - Register a memory region
* @r_xprt: controlling transport
* @seg: memory region co-ordinates
* @nsegs: number of segments remaining
* @writing: true when RDMA Write will be used
* @xid: XID of RPC using the registered memory
* @mr: MR to fill in
*
* Prepare a REG_MR Work Request to register a memory region
* for remote access via RDMA READ or RDMA WRITE.
*
* Returns the next segment or a negative errno pointer.
* On success, @mr is filled in.
*/
struct rpcrdma_mr_seg *frwr_map(struct rpcrdma_xprt *r_xprt,
struct rpcrdma_mr_seg *seg,
int nsegs, bool writing, __be32 xid,
struct rpcrdma_mr *mr)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
struct ib_reg_wr *reg_wr;
struct ib_mr *ibmr;
int i, n;
u8 key;
if (nsegs > ia->ri_max_frwr_depth)
nsegs = ia->ri_max_frwr_depth;
for (i = 0; i < nsegs;) {
if (seg->mr_page)
sg_set_page(&mr->mr_sg[i],
seg->mr_page,
seg->mr_len,
offset_in_page(seg->mr_offset));
else
sg_set_buf(&mr->mr_sg[i], seg->mr_offset,
seg->mr_len);
++seg;
++i;
if (ia->ri_mrtype == IB_MR_TYPE_SG_GAPS)
continue;
if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
break;
}
mr->mr_dir = rpcrdma_data_dir(writing);
mr->mr_nents =
ib_dma_map_sg(ia->ri_id->device, mr->mr_sg, i, mr->mr_dir);
if (!mr->mr_nents)
goto out_dmamap_err;
ibmr = mr->frwr.fr_mr;
n = ib_map_mr_sg(ibmr, mr->mr_sg, mr->mr_nents, NULL, PAGE_SIZE);
if (unlikely(n != mr->mr_nents))
goto out_mapmr_err;
ibmr->iova &= 0x00000000ffffffff;
ibmr->iova |= ((u64)be32_to_cpu(xid)) << 32;
key = (u8)(ibmr->rkey & 0x000000FF);
ib_update_fast_reg_key(ibmr, ++key);
reg_wr = &mr->frwr.fr_regwr;
reg_wr->mr = ibmr;
reg_wr->key = ibmr->rkey;
reg_wr->access = writing ?
IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
IB_ACCESS_REMOTE_READ;
mr->mr_handle = ibmr->rkey;
mr->mr_length = ibmr->length;
mr->mr_offset = ibmr->iova;
trace_xprtrdma_mr_map(mr);
return seg;
out_dmamap_err:
mr->mr_dir = DMA_NONE;
trace_xprtrdma_frwr_sgerr(mr, i);
return ERR_PTR(-EIO);
out_mapmr_err:
trace_xprtrdma_frwr_maperr(mr, n);
return ERR_PTR(-EIO);
}
/**
* frwr_wc_fastreg - Invoked by RDMA provider for a flushed FastReg WC
* @cq: completion queue (ignored)
* @wc: completed WR
*
*/
static void frwr_wc_fastreg(struct ib_cq *cq, struct ib_wc *wc)
{
struct ib_cqe *cqe = wc->wr_cqe;
struct rpcrdma_frwr *frwr =
container_of(cqe, struct rpcrdma_frwr, fr_cqe);
/* WARNING: Only wr_cqe and status are reliable at this point */
trace_xprtrdma_wc_fastreg(wc, frwr);
/* The MR will get recycled when the associated req is retransmitted */
}
/**
* frwr_send - post Send WR containing the RPC Call message
* @ia: interface adapter
* @req: Prepared RPC Call
*
* For FRWR, chain any FastReg WRs to the Send WR. Only a
* single ib_post_send call is needed to register memory
* and then post the Send WR.
*
* Returns the result of ib_post_send.
*/
int frwr_send(struct rpcrdma_ia *ia, struct rpcrdma_req *req)
{
struct ib_send_wr *post_wr;
struct rpcrdma_mr *mr;
post_wr = &req->rl_sendctx->sc_wr;
list_for_each_entry(mr, &req->rl_registered, mr_list) {
struct rpcrdma_frwr *frwr;
frwr = &mr->frwr;
frwr->fr_cqe.done = frwr_wc_fastreg;
frwr->fr_regwr.wr.next = post_wr;
frwr->fr_regwr.wr.wr_cqe = &frwr->fr_cqe;
frwr->fr_regwr.wr.num_sge = 0;
frwr->fr_regwr.wr.opcode = IB_WR_REG_MR;
frwr->fr_regwr.wr.send_flags = 0;
post_wr = &frwr->fr_regwr.wr;
}
/* If ib_post_send fails, the next ->send_request for
* @req will queue these MRs for recovery.
*/
return ib_post_send(ia->ri_id->qp, post_wr, NULL);
}
/**
* frwr_reminv - handle a remotely invalidated mr on the @mrs list
* @rep: Received reply
* @mrs: list of MRs to check
*
*/
void frwr_reminv(struct rpcrdma_rep *rep, struct list_head *mrs)
{
struct rpcrdma_mr *mr;
list_for_each_entry(mr, mrs, mr_list)
if (mr->mr_handle == rep->rr_inv_rkey) {
list_del_init(&mr->mr_list);
trace_xprtrdma_mr_remoteinv(mr);
rpcrdma_mr_put(mr);
break; /* only one invalidated MR per RPC */
}
}
static void __frwr_release_mr(struct ib_wc *wc, struct rpcrdma_mr *mr)
{
if (wc->status != IB_WC_SUCCESS)
rpcrdma_mr_recycle(mr);
else
rpcrdma_mr_put(mr);
}
/**
* frwr_wc_localinv - Invoked by RDMA provider for a LOCAL_INV WC
* @cq: completion queue (ignored)
* @wc: completed WR
*
*/
static void frwr_wc_localinv(struct ib_cq *cq, struct ib_wc *wc)
{
struct ib_cqe *cqe = wc->wr_cqe;
struct rpcrdma_frwr *frwr =
container_of(cqe, struct rpcrdma_frwr, fr_cqe);
struct rpcrdma_mr *mr = container_of(frwr, struct rpcrdma_mr, frwr);
/* WARNING: Only wr_cqe and status are reliable at this point */
trace_xprtrdma_wc_li(wc, frwr);
__frwr_release_mr(wc, mr);
}
/**
* frwr_wc_localinv_wake - Invoked by RDMA provider for a LOCAL_INV WC
* @cq: completion queue (ignored)
* @wc: completed WR
*
* Awaken anyone waiting for an MR to finish being fenced.
*/
static void frwr_wc_localinv_wake(struct ib_cq *cq, struct ib_wc *wc)
{
struct ib_cqe *cqe = wc->wr_cqe;
struct rpcrdma_frwr *frwr =
container_of(cqe, struct rpcrdma_frwr, fr_cqe);
struct rpcrdma_mr *mr = container_of(frwr, struct rpcrdma_mr, frwr);
/* WARNING: Only wr_cqe and status are reliable at this point */
trace_xprtrdma_wc_li_wake(wc, frwr);
__frwr_release_mr(wc, mr);
complete(&frwr->fr_linv_done);
}
/**
* frwr_unmap_sync - invalidate memory regions that were registered for @req
* @r_xprt: controlling transport instance
* @req: rpcrdma_req with a non-empty list of MRs to process
*
* Sleeps until it is safe for the host CPU to access the previously mapped
* memory regions. This guarantees that registered MRs are properly fenced
* from the server before the RPC consumer accesses the data in them. It
* also ensures proper Send flow control: waking the next RPC waits until
* this RPC has relinquished all its Send Queue entries.
*/
void frwr_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
{
struct ib_send_wr *first, **prev, *last;
const struct ib_send_wr *bad_wr;
struct rpcrdma_frwr *frwr;
struct rpcrdma_mr *mr;
int rc;
/* ORDER: Invalidate all of the MRs first
*
* Chain the LOCAL_INV Work Requests and post them with
* a single ib_post_send() call.
*/
frwr = NULL;
prev = &first;
while ((mr = rpcrdma_mr_pop(&req->rl_registered))) {
trace_xprtrdma_mr_localinv(mr);
r_xprt->rx_stats.local_inv_needed++;
frwr = &mr->frwr;
frwr->fr_cqe.done = frwr_wc_localinv;
last = &frwr->fr_invwr;
last->next = NULL;
last->wr_cqe = &frwr->fr_cqe;
last->sg_list = NULL;
last->num_sge = 0;
last->opcode = IB_WR_LOCAL_INV;
last->send_flags = IB_SEND_SIGNALED;
last->ex.invalidate_rkey = mr->mr_handle;
*prev = last;
prev = &last->next;
}
/* Strong send queue ordering guarantees that when the
* last WR in the chain completes, all WRs in the chain
* are complete.
*/
frwr->fr_cqe.done = frwr_wc_localinv_wake;
reinit_completion(&frwr->fr_linv_done);
/* Transport disconnect drains the receive CQ before it
* replaces the QP. The RPC reply handler won't call us
* unless ri_id->qp is a valid pointer.
*/
bad_wr = NULL;
rc = ib_post_send(r_xprt->rx_ia.ri_id->qp, first, &bad_wr);
trace_xprtrdma_post_send(req, rc);
/* The final LOCAL_INV WR in the chain is supposed to
* do the wake. If it was never posted, the wake will
* not happen, so don't wait in that case.
*/
if (bad_wr != first)
wait_for_completion(&frwr->fr_linv_done);
if (!rc)
return;
/* Recycle MRs in the LOCAL_INV chain that did not get posted.
*/
while (bad_wr) {
frwr = container_of(bad_wr, struct rpcrdma_frwr,
fr_invwr);
mr = container_of(frwr, struct rpcrdma_mr, frwr);
bad_wr = bad_wr->next;
list_del_init(&mr->mr_list);
rpcrdma_mr_recycle(mr);
}
}
/**
* frwr_wc_localinv_done - Invoked by RDMA provider for a signaled LOCAL_INV WC
* @cq: completion queue (ignored)
* @wc: completed WR
*
*/
static void frwr_wc_localinv_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct ib_cqe *cqe = wc->wr_cqe;
struct rpcrdma_frwr *frwr =
container_of(cqe, struct rpcrdma_frwr, fr_cqe);
struct rpcrdma_mr *mr = container_of(frwr, struct rpcrdma_mr, frwr);
struct rpcrdma_rep *rep = mr->mr_req->rl_reply;
/* WARNING: Only wr_cqe and status are reliable at this point */
trace_xprtrdma_wc_li_done(wc, frwr);
__frwr_release_mr(wc, mr);
/* Ensure @rep is generated before __frwr_release_mr */
smp_rmb();
rpcrdma_complete_rqst(rep);
}
/**
* frwr_unmap_async - invalidate memory regions that were registered for @req
* @r_xprt: controlling transport instance
* @req: rpcrdma_req with a non-empty list of MRs to process
*
* This guarantees that registered MRs are properly fenced from the
* server before the RPC consumer accesses the data in them. It also
* ensures proper Send flow control: waking the next RPC waits until
* this RPC has relinquished all its Send Queue entries.
*/
void frwr_unmap_async(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
{
struct ib_send_wr *first, *last, **prev;
const struct ib_send_wr *bad_wr;
struct rpcrdma_frwr *frwr;
struct rpcrdma_mr *mr;
int rc;
/* Chain the LOCAL_INV Work Requests and post them with
* a single ib_post_send() call.
*/
frwr = NULL;
prev = &first;
while ((mr = rpcrdma_mr_pop(&req->rl_registered))) {
trace_xprtrdma_mr_localinv(mr);
r_xprt->rx_stats.local_inv_needed++;
frwr = &mr->frwr;
frwr->fr_cqe.done = frwr_wc_localinv;
last = &frwr->fr_invwr;
last->next = NULL;
last->wr_cqe = &frwr->fr_cqe;
last->sg_list = NULL;
last->num_sge = 0;
last->opcode = IB_WR_LOCAL_INV;
last->send_flags = IB_SEND_SIGNALED;
last->ex.invalidate_rkey = mr->mr_handle;
*prev = last;
prev = &last->next;
}
/* Strong send queue ordering guarantees that when the
* last WR in the chain completes, all WRs in the chain
* are complete. The last completion will wake up the
* RPC waiter.
*/
frwr->fr_cqe.done = frwr_wc_localinv_done;
/* Transport disconnect drains the receive CQ before it
* replaces the QP. The RPC reply handler won't call us
* unless ri_id->qp is a valid pointer.
*/
bad_wr = NULL;
rc = ib_post_send(r_xprt->rx_ia.ri_id->qp, first, &bad_wr);
trace_xprtrdma_post_send(req, rc);
if (!rc)
return;
/* Recycle MRs in the LOCAL_INV chain that did not get posted.
*/
while (bad_wr) {
frwr = container_of(bad_wr, struct rpcrdma_frwr, fr_invwr);
mr = container_of(frwr, struct rpcrdma_mr, frwr);
bad_wr = bad_wr->next;
rpcrdma_mr_recycle(mr);
}
/* The final LOCAL_INV WR in the chain is supposed to
* do the wake. If it was never posted, the wake will
* not happen, so wake here in that case.
*/
rpcrdma_complete_rqst(req->rl_reply);
}