diff options
Diffstat (limited to 'net/sunrpc/xprtrdma/rpc_rdma.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/rpc_rdma.c | 889 |
1 files changed, 889 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c new file mode 100644 index 000000000..2c53ea9e1 --- /dev/null +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -0,0 +1,889 @@ +/* + * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the BSD-type + * license below: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * Neither the name of the Network Appliance, Inc. 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. + */ + +/* + * rpc_rdma.c + * + * This file contains the guts of the RPC RDMA protocol, and + * does marshaling/unmarshaling, etc. It is also where interfacing + * to the Linux RPC framework lives. + */ + +#include "xprt_rdma.h" + +#include <linux/highmem.h> + +#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) +# define RPCDBG_FACILITY RPCDBG_TRANS +#endif + +enum rpcrdma_chunktype { + rpcrdma_noch = 0, + rpcrdma_readch, + rpcrdma_areadch, + rpcrdma_writech, + rpcrdma_replych +}; + +#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) +static const char transfertypes[][12] = { + "pure inline", /* no chunks */ + " read chunk", /* some argument via rdma read */ + "*read chunk", /* entire request via rdma read */ + "write chunk", /* some result via rdma write */ + "reply chunk" /* entire reply via rdma write */ +}; +#endif + +/* + * Chunk assembly from upper layer xdr_buf. + * + * Prepare the passed-in xdr_buf into representation as RPC/RDMA chunk + * elements. Segments are then coalesced when registered, if possible + * within the selected memreg mode. + * + * Returns positive number of segments converted, or a negative errno. + */ + +static int +rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos, + enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg, int nsegs) +{ + int len, n = 0, p; + int page_base; + struct page **ppages; + + if (pos == 0 && xdrbuf->head[0].iov_len) { + seg[n].mr_page = NULL; + seg[n].mr_offset = xdrbuf->head[0].iov_base; + seg[n].mr_len = xdrbuf->head[0].iov_len; + ++n; + } + + len = xdrbuf->page_len; + ppages = xdrbuf->pages + (xdrbuf->page_base >> PAGE_SHIFT); + page_base = xdrbuf->page_base & ~PAGE_MASK; + p = 0; + while (len && n < nsegs) { + if (!ppages[p]) { + /* alloc the pagelist for receiving buffer */ + ppages[p] = alloc_page(GFP_ATOMIC); + if (!ppages[p]) + return -ENOMEM; + } + seg[n].mr_page = ppages[p]; + seg[n].mr_offset = (void *)(unsigned long) page_base; + seg[n].mr_len = min_t(u32, PAGE_SIZE - page_base, len); + if (seg[n].mr_len > PAGE_SIZE) + return -EIO; + len -= seg[n].mr_len; + ++n; + ++p; + page_base = 0; /* page offset only applies to first page */ + } + + /* Message overflows the seg array */ + if (len && n == nsegs) + return -EIO; + + if (xdrbuf->tail[0].iov_len) { + /* the rpcrdma protocol allows us to omit any trailing + * xdr pad bytes, saving the server an RDMA operation. */ + if (xdrbuf->tail[0].iov_len < 4 && xprt_rdma_pad_optimize) + return n; + if (n == nsegs) + /* Tail remains, but we're out of segments */ + return -EIO; + seg[n].mr_page = NULL; + seg[n].mr_offset = xdrbuf->tail[0].iov_base; + seg[n].mr_len = xdrbuf->tail[0].iov_len; + ++n; + } + + return n; +} + +/* + * Create read/write chunk lists, and reply chunks, for RDMA + * + * Assume check against THRESHOLD has been done, and chunks are required. + * Assume only encoding one list entry for read|write chunks. The NFSv3 + * protocol is simple enough to allow this as it only has a single "bulk + * result" in each procedure - complicated NFSv4 COMPOUNDs are not. (The + * RDMA/Sessions NFSv4 proposal addresses this for future v4 revs.) + * + * When used for a single reply chunk (which is a special write + * chunk used for the entire reply, rather than just the data), it + * is used primarily for READDIR and READLINK which would otherwise + * be severely size-limited by a small rdma inline read max. The server + * response will come back as an RDMA Write, followed by a message + * of type RDMA_NOMSG carrying the xid and length. As a result, reply + * chunks do not provide data alignment, however they do not require + * "fixup" (moving the response to the upper layer buffer) either. + * + * Encoding key for single-list chunks (HLOO = Handle32 Length32 Offset64): + * + * Read chunklist (a linked list): + * N elements, position P (same P for all chunks of same arg!): + * 1 - PHLOO - 1 - PHLOO - ... - 1 - PHLOO - 0 + * + * Write chunklist (a list of (one) counted array): + * N elements: + * 1 - N - HLOO - HLOO - ... - HLOO - 0 + * + * Reply chunk (a counted array): + * N elements: + * 1 - N - HLOO - HLOO - ... - HLOO + * + * Returns positive RPC/RDMA header size, or negative errno. + */ + +static ssize_t +rpcrdma_create_chunks(struct rpc_rqst *rqst, struct xdr_buf *target, + struct rpcrdma_msg *headerp, enum rpcrdma_chunktype type) +{ + struct rpcrdma_req *req = rpcr_to_rdmar(rqst); + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); + int n, nsegs, nchunks = 0; + unsigned int pos; + struct rpcrdma_mr_seg *seg = req->rl_segments; + struct rpcrdma_read_chunk *cur_rchunk = NULL; + struct rpcrdma_write_array *warray = NULL; + struct rpcrdma_write_chunk *cur_wchunk = NULL; + __be32 *iptr = headerp->rm_body.rm_chunks; + int (*map)(struct rpcrdma_xprt *, struct rpcrdma_mr_seg *, int, bool); + + if (type == rpcrdma_readch || type == rpcrdma_areadch) { + /* a read chunk - server will RDMA Read our memory */ + cur_rchunk = (struct rpcrdma_read_chunk *) iptr; + } else { + /* a write or reply chunk - server will RDMA Write our memory */ + *iptr++ = xdr_zero; /* encode a NULL read chunk list */ + if (type == rpcrdma_replych) + *iptr++ = xdr_zero; /* a NULL write chunk list */ + warray = (struct rpcrdma_write_array *) iptr; + cur_wchunk = (struct rpcrdma_write_chunk *) (warray + 1); + } + + if (type == rpcrdma_replych || type == rpcrdma_areadch) + pos = 0; + else + pos = target->head[0].iov_len; + + nsegs = rpcrdma_convert_iovs(target, pos, type, seg, RPCRDMA_MAX_SEGS); + if (nsegs < 0) + return nsegs; + + map = r_xprt->rx_ia.ri_ops->ro_map; + do { + n = map(r_xprt, seg, nsegs, cur_wchunk != NULL); + if (n <= 0) + goto out; + if (cur_rchunk) { /* read */ + cur_rchunk->rc_discrim = xdr_one; + /* all read chunks have the same "position" */ + cur_rchunk->rc_position = cpu_to_be32(pos); + cur_rchunk->rc_target.rs_handle = + cpu_to_be32(seg->mr_rkey); + cur_rchunk->rc_target.rs_length = + cpu_to_be32(seg->mr_len); + xdr_encode_hyper( + (__be32 *)&cur_rchunk->rc_target.rs_offset, + seg->mr_base); + dprintk("RPC: %s: read chunk " + "elem %d@0x%llx:0x%x pos %u (%s)\n", __func__, + seg->mr_len, (unsigned long long)seg->mr_base, + seg->mr_rkey, pos, n < nsegs ? "more" : "last"); + cur_rchunk++; + r_xprt->rx_stats.read_chunk_count++; + } else { /* write/reply */ + cur_wchunk->wc_target.rs_handle = + cpu_to_be32(seg->mr_rkey); + cur_wchunk->wc_target.rs_length = + cpu_to_be32(seg->mr_len); + xdr_encode_hyper( + (__be32 *)&cur_wchunk->wc_target.rs_offset, + seg->mr_base); + dprintk("RPC: %s: %s chunk " + "elem %d@0x%llx:0x%x (%s)\n", __func__, + (type == rpcrdma_replych) ? "reply" : "write", + seg->mr_len, (unsigned long long)seg->mr_base, + seg->mr_rkey, n < nsegs ? "more" : "last"); + cur_wchunk++; + if (type == rpcrdma_replych) + r_xprt->rx_stats.reply_chunk_count++; + else + r_xprt->rx_stats.write_chunk_count++; + r_xprt->rx_stats.total_rdma_request += seg->mr_len; + } + nchunks++; + seg += n; + nsegs -= n; + } while (nsegs); + + /* success. all failures return above */ + req->rl_nchunks = nchunks; + + /* + * finish off header. If write, marshal discrim and nchunks. + */ + if (cur_rchunk) { + iptr = (__be32 *) cur_rchunk; + *iptr++ = xdr_zero; /* finish the read chunk list */ + *iptr++ = xdr_zero; /* encode a NULL write chunk list */ + *iptr++ = xdr_zero; /* encode a NULL reply chunk */ + } else { + warray->wc_discrim = xdr_one; + warray->wc_nchunks = cpu_to_be32(nchunks); + iptr = (__be32 *) cur_wchunk; + if (type == rpcrdma_writech) { + *iptr++ = xdr_zero; /* finish the write chunk list */ + *iptr++ = xdr_zero; /* encode a NULL reply chunk */ + } + } + + /* + * Return header size. + */ + return (unsigned char *)iptr - (unsigned char *)headerp; + +out: + if (r_xprt->rx_ia.ri_memreg_strategy == RPCRDMA_FRMR) + return n; + + for (pos = 0; nchunks--;) + pos += r_xprt->rx_ia.ri_ops->ro_unmap(r_xprt, + &req->rl_segments[pos]); + return n; +} + +/* + * Copy write data inline. + * This function is used for "small" requests. Data which is passed + * to RPC via iovecs (or page list) is copied directly into the + * pre-registered memory buffer for this request. For small amounts + * of data, this is efficient. The cutoff value is tunable. + */ +static int +rpcrdma_inline_pullup(struct rpc_rqst *rqst, int pad) +{ + int i, npages, curlen; + int copy_len; + unsigned char *srcp, *destp; + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); + int page_base; + struct page **ppages; + + destp = rqst->rq_svec[0].iov_base; + curlen = rqst->rq_svec[0].iov_len; + destp += curlen; + /* + * Do optional padding where it makes sense. Alignment of write + * payload can help the server, if our setting is accurate. + */ + pad -= (curlen + 36/*sizeof(struct rpcrdma_msg_padded)*/); + if (pad < 0 || rqst->rq_slen - curlen < RPCRDMA_INLINE_PAD_THRESH) + pad = 0; /* don't pad this request */ + + dprintk("RPC: %s: pad %d destp 0x%p len %d hdrlen %d\n", + __func__, pad, destp, rqst->rq_slen, curlen); + + copy_len = rqst->rq_snd_buf.page_len; + + if (rqst->rq_snd_buf.tail[0].iov_len) { + curlen = rqst->rq_snd_buf.tail[0].iov_len; + if (destp + copy_len != rqst->rq_snd_buf.tail[0].iov_base) { + memmove(destp + copy_len, + rqst->rq_snd_buf.tail[0].iov_base, curlen); + r_xprt->rx_stats.pullup_copy_count += curlen; + } + dprintk("RPC: %s: tail destp 0x%p len %d\n", + __func__, destp + copy_len, curlen); + rqst->rq_svec[0].iov_len += curlen; + } + r_xprt->rx_stats.pullup_copy_count += copy_len; + + page_base = rqst->rq_snd_buf.page_base; + ppages = rqst->rq_snd_buf.pages + (page_base >> PAGE_SHIFT); + page_base &= ~PAGE_MASK; + npages = PAGE_ALIGN(page_base+copy_len) >> PAGE_SHIFT; + for (i = 0; copy_len && i < npages; i++) { + curlen = PAGE_SIZE - page_base; + if (curlen > copy_len) + curlen = copy_len; + dprintk("RPC: %s: page %d destp 0x%p len %d curlen %d\n", + __func__, i, destp, copy_len, curlen); + srcp = kmap_atomic(ppages[i]); + memcpy(destp, srcp+page_base, curlen); + kunmap_atomic(srcp); + rqst->rq_svec[0].iov_len += curlen; + destp += curlen; + copy_len -= curlen; + page_base = 0; + } + /* header now contains entire send message */ + return pad; +} + +/* + * Marshal a request: the primary job of this routine is to choose + * the transfer modes. See comments below. + * + * Uses multiple RDMA IOVs for a request: + * [0] -- RPC RDMA header, which uses memory from the *start* of the + * preregistered buffer that already holds the RPC data in + * its middle. + * [1] -- the RPC header/data, marshaled by RPC and the NFS protocol. + * [2] -- optional padding. + * [3] -- if padded, header only in [1] and data here. + * + * Returns zero on success, otherwise a negative errno. + */ + +int +rpcrdma_marshal_req(struct rpc_rqst *rqst) +{ + struct rpc_xprt *xprt = rqst->rq_xprt; + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); + struct rpcrdma_req *req = rpcr_to_rdmar(rqst); + char *base; + size_t rpclen, padlen; + ssize_t hdrlen; + enum rpcrdma_chunktype rtype, wtype; + struct rpcrdma_msg *headerp; + + /* + * rpclen gets amount of data in first buffer, which is the + * pre-registered buffer. + */ + base = rqst->rq_svec[0].iov_base; + rpclen = rqst->rq_svec[0].iov_len; + + headerp = rdmab_to_msg(req->rl_rdmabuf); + /* don't byte-swap XID, it's already done in request */ + headerp->rm_xid = rqst->rq_xid; + headerp->rm_vers = rpcrdma_version; + headerp->rm_credit = cpu_to_be32(r_xprt->rx_buf.rb_max_requests); + headerp->rm_type = rdma_msg; + + /* + * Chunks needed for results? + * + * o If the expected result is under the inline threshold, all ops + * return as inline (but see later). + * o Large non-read ops return as a single reply chunk. + * o Large read ops return data as write chunk(s), header as inline. + * + * Note: the NFS code sending down multiple result segments implies + * the op is one of read, readdir[plus], readlink or NFSv4 getacl. + */ + + /* + * This code can handle read chunks, write chunks OR reply + * chunks -- only one type. If the request is too big to fit + * inline, then we will choose read chunks. If the request is + * a READ, then use write chunks to separate the file data + * into pages; otherwise use reply chunks. + */ + if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst)) + wtype = rpcrdma_noch; + else if (rqst->rq_rcv_buf.page_len == 0) + wtype = rpcrdma_replych; + else if (rqst->rq_rcv_buf.flags & XDRBUF_READ) + wtype = rpcrdma_writech; + else + wtype = rpcrdma_replych; + + /* + * Chunks needed for arguments? + * + * o If the total request is under the inline threshold, all ops + * are sent as inline. + * o Large non-write ops are sent with the entire message as a + * single read chunk (protocol 0-position special case). + * o Large write ops transmit data as read chunk(s), header as + * inline. + * + * Note: the NFS code sending down multiple argument segments + * implies the op is a write. + * TBD check NFSv4 setacl + */ + if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst)) + rtype = rpcrdma_noch; + else if (rqst->rq_snd_buf.page_len == 0) + rtype = rpcrdma_areadch; + else + rtype = rpcrdma_readch; + + /* The following simplification is not true forever */ + if (rtype != rpcrdma_noch && wtype == rpcrdma_replych) + wtype = rpcrdma_noch; + if (rtype != rpcrdma_noch && wtype != rpcrdma_noch) { + dprintk("RPC: %s: cannot marshal multiple chunk lists\n", + __func__); + return -EIO; + } + + hdrlen = RPCRDMA_HDRLEN_MIN; + padlen = 0; + + /* + * Pull up any extra send data into the preregistered buffer. + * When padding is in use and applies to the transfer, insert + * it and change the message type. + */ + if (rtype == rpcrdma_noch) { + + padlen = rpcrdma_inline_pullup(rqst, + RPCRDMA_INLINE_PAD_VALUE(rqst)); + + if (padlen) { + headerp->rm_type = rdma_msgp; + headerp->rm_body.rm_padded.rm_align = + cpu_to_be32(RPCRDMA_INLINE_PAD_VALUE(rqst)); + headerp->rm_body.rm_padded.rm_thresh = + cpu_to_be32(RPCRDMA_INLINE_PAD_THRESH); + headerp->rm_body.rm_padded.rm_pempty[0] = xdr_zero; + headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero; + headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero; + hdrlen += 2 * sizeof(u32); /* extra words in padhdr */ + if (wtype != rpcrdma_noch) { + dprintk("RPC: %s: invalid chunk list\n", + __func__); + return -EIO; + } + } else { + headerp->rm_body.rm_nochunks.rm_empty[0] = xdr_zero; + headerp->rm_body.rm_nochunks.rm_empty[1] = xdr_zero; + headerp->rm_body.rm_nochunks.rm_empty[2] = xdr_zero; + /* new length after pullup */ + rpclen = rqst->rq_svec[0].iov_len; + /* + * Currently we try to not actually use read inline. + * Reply chunks have the desirable property that + * they land, packed, directly in the target buffers + * without headers, so they require no fixup. The + * additional RDMA Write op sends the same amount + * of data, streams on-the-wire and adds no overhead + * on receive. Therefore, we request a reply chunk + * for non-writes wherever feasible and efficient. + */ + if (wtype == rpcrdma_noch) + wtype = rpcrdma_replych; + } + } + + if (rtype != rpcrdma_noch) { + hdrlen = rpcrdma_create_chunks(rqst, &rqst->rq_snd_buf, + headerp, rtype); + wtype = rtype; /* simplify dprintk */ + + } else if (wtype != rpcrdma_noch) { + hdrlen = rpcrdma_create_chunks(rqst, &rqst->rq_rcv_buf, + headerp, wtype); + } + if (hdrlen < 0) + return hdrlen; + + dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd" + " headerp 0x%p base 0x%p lkey 0x%x\n", + __func__, transfertypes[wtype], hdrlen, rpclen, padlen, + headerp, base, rdmab_lkey(req->rl_rdmabuf)); + + /* + * initialize send_iov's - normally only two: rdma chunk header and + * single preregistered RPC header buffer, but if padding is present, + * then use a preregistered (and zeroed) pad buffer between the RPC + * header and any write data. In all non-rdma cases, any following + * data has been copied into the RPC header buffer. + */ + req->rl_send_iov[0].addr = rdmab_addr(req->rl_rdmabuf); + req->rl_send_iov[0].length = hdrlen; + req->rl_send_iov[0].lkey = rdmab_lkey(req->rl_rdmabuf); + + req->rl_send_iov[1].addr = rdmab_addr(req->rl_sendbuf); + req->rl_send_iov[1].length = rpclen; + req->rl_send_iov[1].lkey = rdmab_lkey(req->rl_sendbuf); + + req->rl_niovs = 2; + + if (padlen) { + struct rpcrdma_ep *ep = &r_xprt->rx_ep; + + req->rl_send_iov[2].addr = rdmab_addr(ep->rep_padbuf); + req->rl_send_iov[2].length = padlen; + req->rl_send_iov[2].lkey = rdmab_lkey(ep->rep_padbuf); + + req->rl_send_iov[3].addr = req->rl_send_iov[1].addr + rpclen; + req->rl_send_iov[3].length = rqst->rq_slen - rpclen; + req->rl_send_iov[3].lkey = rdmab_lkey(req->rl_sendbuf); + + req->rl_niovs = 4; + } + + return 0; +} + +/* + * Chase down a received write or reply chunklist to get length + * RDMA'd by server. See map at rpcrdma_create_chunks()! :-) + */ +static int +rpcrdma_count_chunks(struct rpcrdma_rep *rep, unsigned int max, int wrchunk, __be32 **iptrp) +{ + unsigned int i, total_len; + struct rpcrdma_write_chunk *cur_wchunk; + char *base = (char *)rdmab_to_msg(rep->rr_rdmabuf); + + i = be32_to_cpu(**iptrp); + if (i > max) + return -1; + cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1); + total_len = 0; + while (i--) { + struct rpcrdma_segment *seg = &cur_wchunk->wc_target; + ifdebug(FACILITY) { + u64 off; + xdr_decode_hyper((__be32 *)&seg->rs_offset, &off); + dprintk("RPC: %s: chunk %d@0x%llx:0x%x\n", + __func__, + be32_to_cpu(seg->rs_length), + (unsigned long long)off, + be32_to_cpu(seg->rs_handle)); + } + total_len += be32_to_cpu(seg->rs_length); + ++cur_wchunk; + } + /* check and adjust for properly terminated write chunk */ + if (wrchunk) { + __be32 *w = (__be32 *) cur_wchunk; + if (*w++ != xdr_zero) + return -1; + cur_wchunk = (struct rpcrdma_write_chunk *) w; + } + if ((char *)cur_wchunk > base + rep->rr_len) + return -1; + + *iptrp = (__be32 *) cur_wchunk; + return total_len; +} + +/* + * Scatter inline received data back into provided iov's. + */ +static void +rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) +{ + int i, npages, curlen, olen; + char *destp; + struct page **ppages; + int page_base; + + curlen = rqst->rq_rcv_buf.head[0].iov_len; + if (curlen > copy_len) { /* write chunk header fixup */ + curlen = copy_len; + rqst->rq_rcv_buf.head[0].iov_len = curlen; + } + + dprintk("RPC: %s: srcp 0x%p len %d hdrlen %d\n", + __func__, srcp, copy_len, curlen); + + /* Shift pointer for first receive segment only */ + rqst->rq_rcv_buf.head[0].iov_base = srcp; + srcp += curlen; + copy_len -= curlen; + + olen = copy_len; + i = 0; + rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen; + page_base = rqst->rq_rcv_buf.page_base; + ppages = rqst->rq_rcv_buf.pages + (page_base >> PAGE_SHIFT); + page_base &= ~PAGE_MASK; + + if (copy_len && rqst->rq_rcv_buf.page_len) { + npages = PAGE_ALIGN(page_base + + rqst->rq_rcv_buf.page_len) >> PAGE_SHIFT; + for (; i < npages; i++) { + curlen = PAGE_SIZE - page_base; + if (curlen > copy_len) + curlen = copy_len; + dprintk("RPC: %s: page %d" + " srcp 0x%p len %d curlen %d\n", + __func__, i, srcp, copy_len, curlen); + destp = kmap_atomic(ppages[i]); + memcpy(destp + page_base, srcp, curlen); + flush_dcache_page(ppages[i]); + kunmap_atomic(destp); + srcp += curlen; + copy_len -= curlen; + if (copy_len == 0) + break; + page_base = 0; + } + } + + if (copy_len && rqst->rq_rcv_buf.tail[0].iov_len) { + curlen = copy_len; + if (curlen > rqst->rq_rcv_buf.tail[0].iov_len) + curlen = rqst->rq_rcv_buf.tail[0].iov_len; + if (rqst->rq_rcv_buf.tail[0].iov_base != srcp) + memmove(rqst->rq_rcv_buf.tail[0].iov_base, srcp, curlen); + dprintk("RPC: %s: tail srcp 0x%p len %d curlen %d\n", + __func__, srcp, copy_len, curlen); + rqst->rq_rcv_buf.tail[0].iov_len = curlen; + copy_len -= curlen; ++i; + } else + rqst->rq_rcv_buf.tail[0].iov_len = 0; + + if (pad) { + /* implicit padding on terminal chunk */ + unsigned char *p = rqst->rq_rcv_buf.tail[0].iov_base; + while (pad--) + p[rqst->rq_rcv_buf.tail[0].iov_len++] = 0; + } + + if (copy_len) + dprintk("RPC: %s: %d bytes in" + " %d extra segments (%d lost)\n", + __func__, olen, i, copy_len); + + /* TBD avoid a warning from call_decode() */ + rqst->rq_private_buf = rqst->rq_rcv_buf; +} + +void +rpcrdma_connect_worker(struct work_struct *work) +{ + struct rpcrdma_ep *ep = + container_of(work, struct rpcrdma_ep, rep_connect_worker.work); + struct rpcrdma_xprt *r_xprt = + container_of(ep, struct rpcrdma_xprt, rx_ep); + struct rpc_xprt *xprt = &r_xprt->rx_xprt; + + spin_lock_bh(&xprt->transport_lock); + if (++xprt->connect_cookie == 0) /* maintain a reserved value */ + ++xprt->connect_cookie; + if (ep->rep_connected > 0) { + if (!xprt_test_and_set_connected(xprt)) + xprt_wake_pending_tasks(xprt, 0); + } else { + if (xprt_test_and_clear_connected(xprt)) + xprt_wake_pending_tasks(xprt, -ENOTCONN); + } + spin_unlock_bh(&xprt->transport_lock); +} + +/* + * This function is called when an async event is posted to + * the connection which changes the connection state. All it + * does at this point is mark the connection up/down, the rpc + * timers do the rest. + */ +void +rpcrdma_conn_func(struct rpcrdma_ep *ep) +{ + schedule_delayed_work(&ep->rep_connect_worker, 0); +} + +/* + * Called as a tasklet to do req/reply match and complete a request + * Errors must result in the RPC task either being awakened, or + * allowed to timeout, to discover the errors at that time. + */ +void +rpcrdma_reply_handler(struct rpcrdma_rep *rep) +{ + struct rpcrdma_msg *headerp; + struct rpcrdma_req *req; + struct rpc_rqst *rqst; + struct rpc_xprt *xprt = rep->rr_xprt; + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); + __be32 *iptr; + int rdmalen, status; + unsigned long cwnd; + u32 credits; + + /* Check status. If bad, signal disconnect and return rep to pool */ + if (rep->rr_len == ~0U) { + rpcrdma_recv_buffer_put(rep); + if (r_xprt->rx_ep.rep_connected == 1) { + r_xprt->rx_ep.rep_connected = -EIO; + rpcrdma_conn_func(&r_xprt->rx_ep); + } + return; + } + if (rep->rr_len < RPCRDMA_HDRLEN_MIN) { + dprintk("RPC: %s: short/invalid reply\n", __func__); + goto repost; + } + headerp = rdmab_to_msg(rep->rr_rdmabuf); + if (headerp->rm_vers != rpcrdma_version) { + dprintk("RPC: %s: invalid version %d\n", + __func__, be32_to_cpu(headerp->rm_vers)); + goto repost; + } + + /* Get XID and try for a match. */ + spin_lock(&xprt->transport_lock); + rqst = xprt_lookup_rqst(xprt, headerp->rm_xid); + if (rqst == NULL) { + spin_unlock(&xprt->transport_lock); + dprintk("RPC: %s: reply 0x%p failed " + "to match any request xid 0x%08x len %d\n", + __func__, rep, be32_to_cpu(headerp->rm_xid), + rep->rr_len); +repost: + r_xprt->rx_stats.bad_reply_count++; + rep->rr_func = rpcrdma_reply_handler; + if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, &r_xprt->rx_ep, rep)) + rpcrdma_recv_buffer_put(rep); + + return; + } + + /* get request object */ + req = rpcr_to_rdmar(rqst); + if (req->rl_reply) { + spin_unlock(&xprt->transport_lock); + dprintk("RPC: %s: duplicate reply 0x%p to RPC " + "request 0x%p: xid 0x%08x\n", __func__, rep, req, + be32_to_cpu(headerp->rm_xid)); + goto repost; + } + + dprintk("RPC: %s: reply 0x%p completes request 0x%p\n" + " RPC request 0x%p xid 0x%08x\n", + __func__, rep, req, rqst, + be32_to_cpu(headerp->rm_xid)); + + /* from here on, the reply is no longer an orphan */ + req->rl_reply = rep; + xprt->reestablish_timeout = 0; + + /* check for expected message types */ + /* The order of some of these tests is important. */ + switch (headerp->rm_type) { + case rdma_msg: + /* never expect read chunks */ + /* never expect reply chunks (two ways to check) */ + /* never expect write chunks without having offered RDMA */ + if (headerp->rm_body.rm_chunks[0] != xdr_zero || + (headerp->rm_body.rm_chunks[1] == xdr_zero && + headerp->rm_body.rm_chunks[2] != xdr_zero) || + (headerp->rm_body.rm_chunks[1] != xdr_zero && + req->rl_nchunks == 0)) + goto badheader; + if (headerp->rm_body.rm_chunks[1] != xdr_zero) { + /* count any expected write chunks in read reply */ + /* start at write chunk array count */ + iptr = &headerp->rm_body.rm_chunks[2]; + rdmalen = rpcrdma_count_chunks(rep, + req->rl_nchunks, 1, &iptr); + /* check for validity, and no reply chunk after */ + if (rdmalen < 0 || *iptr++ != xdr_zero) + goto badheader; + rep->rr_len -= + ((unsigned char *)iptr - (unsigned char *)headerp); + status = rep->rr_len + rdmalen; + r_xprt->rx_stats.total_rdma_reply += rdmalen; + /* special case - last chunk may omit padding */ + if (rdmalen &= 3) { + rdmalen = 4 - rdmalen; + status += rdmalen; + } + } else { + /* else ordinary inline */ + rdmalen = 0; + iptr = (__be32 *)((unsigned char *)headerp + + RPCRDMA_HDRLEN_MIN); + rep->rr_len -= RPCRDMA_HDRLEN_MIN; + status = rep->rr_len; + } + /* Fix up the rpc results for upper layer */ + rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len, rdmalen); + break; + + case rdma_nomsg: + /* never expect read or write chunks, always reply chunks */ + if (headerp->rm_body.rm_chunks[0] != xdr_zero || + headerp->rm_body.rm_chunks[1] != xdr_zero || + headerp->rm_body.rm_chunks[2] != xdr_one || + req->rl_nchunks == 0) + goto badheader; + iptr = (__be32 *)((unsigned char *)headerp + + RPCRDMA_HDRLEN_MIN); + rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr); + if (rdmalen < 0) + goto badheader; + r_xprt->rx_stats.total_rdma_reply += rdmalen; + /* Reply chunk buffer already is the reply vector - no fixup. */ + status = rdmalen; + break; + +badheader: + default: + dprintk("%s: invalid rpcrdma reply header (type %d):" + " chunks[012] == %d %d %d" + " expected chunks <= %d\n", + __func__, be32_to_cpu(headerp->rm_type), + headerp->rm_body.rm_chunks[0], + headerp->rm_body.rm_chunks[1], + headerp->rm_body.rm_chunks[2], + req->rl_nchunks); + status = -EIO; + r_xprt->rx_stats.bad_reply_count++; + break; + } + + credits = be32_to_cpu(headerp->rm_credit); + if (credits == 0) + credits = 1; /* don't deadlock */ + else if (credits > r_xprt->rx_buf.rb_max_requests) + credits = r_xprt->rx_buf.rb_max_requests; + + cwnd = xprt->cwnd; + xprt->cwnd = credits << RPC_CWNDSHIFT; + if (xprt->cwnd > cwnd) + xprt_release_rqst_cong(rqst->rq_task); + + dprintk("RPC: %s: xprt_complete_rqst(0x%p, 0x%p, %d)\n", + __func__, xprt, rqst, status); + xprt_complete_rqst(rqst->rq_task, status); + spin_unlock(&xprt->transport_lock); +} |