From 7875e18e09961d29f30424c5e2e48e704dc3789b Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Tue, 24 Feb 2009 15:30:26 +0000 Subject: RDS: Message parsing Parsing of newly-received RDS message headers (including ext. headers) and copy-to/from-user routines. page.c implements a per-cpu page remainder cache, to reduce the number of allocations needed for small datagrams. Signed-off-by: Andy Grover Signed-off-by: David S. Miller --- net/rds/message.c | 402 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 402 insertions(+) create mode 100644 net/rds/message.c (limited to 'net/rds/message.c') diff --git a/net/rds/message.c b/net/rds/message.c new file mode 100644 index 000000000000..5a15dc8d0cd7 --- /dev/null +++ b/net/rds/message.c @@ -0,0 +1,402 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include + +#include "rds.h" +#include "rdma.h" + +static DECLARE_WAIT_QUEUE_HEAD(rds_message_flush_waitq); + +static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = { +[RDS_EXTHDR_NONE] = 0, +[RDS_EXTHDR_VERSION] = sizeof(struct rds_ext_header_version), +[RDS_EXTHDR_RDMA] = sizeof(struct rds_ext_header_rdma), +[RDS_EXTHDR_RDMA_DEST] = sizeof(struct rds_ext_header_rdma_dest), +}; + + +void rds_message_addref(struct rds_message *rm) +{ + rdsdebug("addref rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); + atomic_inc(&rm->m_refcount); +} + +/* + * This relies on dma_map_sg() not touching sg[].page during merging. + */ +static void rds_message_purge(struct rds_message *rm) +{ + unsigned long i; + + if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags))) + return; + + for (i = 0; i < rm->m_nents; i++) { + rdsdebug("putting data page %p\n", (void *)sg_page(&rm->m_sg[i])); + /* XXX will have to put_page for page refs */ + __free_page(sg_page(&rm->m_sg[i])); + } + rm->m_nents = 0; + + if (rm->m_rdma_op) + rds_rdma_free_op(rm->m_rdma_op); + if (rm->m_rdma_mr) + rds_mr_put(rm->m_rdma_mr); +} + +void rds_message_inc_purge(struct rds_incoming *inc) +{ + struct rds_message *rm = container_of(inc, struct rds_message, m_inc); + rds_message_purge(rm); +} + +void rds_message_put(struct rds_message *rm) +{ + rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); + + if (atomic_dec_and_test(&rm->m_refcount)) { + BUG_ON(!list_empty(&rm->m_sock_item)); + BUG_ON(!list_empty(&rm->m_conn_item)); + rds_message_purge(rm); + + kfree(rm); + } +} + +void rds_message_inc_free(struct rds_incoming *inc) +{ + struct rds_message *rm = container_of(inc, struct rds_message, m_inc); + rds_message_put(rm); +} + +void rds_message_populate_header(struct rds_header *hdr, __be16 sport, + __be16 dport, u64 seq) +{ + hdr->h_flags = 0; + hdr->h_sport = sport; + hdr->h_dport = dport; + hdr->h_sequence = cpu_to_be64(seq); + hdr->h_exthdr[0] = RDS_EXTHDR_NONE; +} + +int rds_message_add_extension(struct rds_header *hdr, + unsigned int type, const void *data, unsigned int len) +{ + unsigned int ext_len = sizeof(u8) + len; + unsigned char *dst; + + /* For now, refuse to add more than one extension header */ + if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE) + return 0; + + if (type >= __RDS_EXTHDR_MAX + || len != rds_exthdr_size[type]) + return 0; + + if (ext_len >= RDS_HEADER_EXT_SPACE) + return 0; + dst = hdr->h_exthdr; + + *dst++ = type; + memcpy(dst, data, len); + + dst[len] = RDS_EXTHDR_NONE; + return 1; +} + +/* + * If a message has extension headers, retrieve them here. + * Call like this: + * + * unsigned int pos = 0; + * + * while (1) { + * buflen = sizeof(buffer); + * type = rds_message_next_extension(hdr, &pos, buffer, &buflen); + * if (type == RDS_EXTHDR_NONE) + * break; + * ... + * } + */ +int rds_message_next_extension(struct rds_header *hdr, + unsigned int *pos, void *buf, unsigned int *buflen) +{ + unsigned int offset, ext_type, ext_len; + u8 *src = hdr->h_exthdr; + + offset = *pos; + if (offset >= RDS_HEADER_EXT_SPACE) + goto none; + + /* Get the extension type and length. For now, the + * length is implied by the extension type. */ + ext_type = src[offset++]; + + if (ext_type == RDS_EXTHDR_NONE || ext_type >= __RDS_EXTHDR_MAX) + goto none; + ext_len = rds_exthdr_size[ext_type]; + if (offset + ext_len > RDS_HEADER_EXT_SPACE) + goto none; + + *pos = offset + ext_len; + if (ext_len < *buflen) + *buflen = ext_len; + memcpy(buf, src + offset, *buflen); + return ext_type; + +none: + *pos = RDS_HEADER_EXT_SPACE; + *buflen = 0; + return RDS_EXTHDR_NONE; +} + +int rds_message_add_version_extension(struct rds_header *hdr, unsigned int version) +{ + struct rds_ext_header_version ext_hdr; + + ext_hdr.h_version = cpu_to_be32(version); + return rds_message_add_extension(hdr, RDS_EXTHDR_VERSION, &ext_hdr, sizeof(ext_hdr)); +} + +int rds_message_get_version_extension(struct rds_header *hdr, unsigned int *version) +{ + struct rds_ext_header_version ext_hdr; + unsigned int pos = 0, len = sizeof(ext_hdr); + + /* We assume the version extension is the only one present */ + if (rds_message_next_extension(hdr, &pos, &ext_hdr, &len) != RDS_EXTHDR_VERSION) + return 0; + *version = be32_to_cpu(ext_hdr.h_version); + return 1; +} + +int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset) +{ + struct rds_ext_header_rdma_dest ext_hdr; + + ext_hdr.h_rdma_rkey = cpu_to_be32(r_key); + ext_hdr.h_rdma_offset = cpu_to_be32(offset); + return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr)); +} + +struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp) +{ + struct rds_message *rm; + + rm = kzalloc(sizeof(struct rds_message) + + (nents * sizeof(struct scatterlist)), gfp); + if (!rm) + goto out; + + if (nents) + sg_init_table(rm->m_sg, nents); + atomic_set(&rm->m_refcount, 1); + INIT_LIST_HEAD(&rm->m_sock_item); + INIT_LIST_HEAD(&rm->m_conn_item); + spin_lock_init(&rm->m_rs_lock); + +out: + return rm; +} + +struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len) +{ + struct rds_message *rm; + unsigned int i; + + rm = rds_message_alloc(ceil(total_len, PAGE_SIZE), GFP_KERNEL); + if (rm == NULL) + return ERR_PTR(-ENOMEM); + + set_bit(RDS_MSG_PAGEVEC, &rm->m_flags); + rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); + rm->m_nents = ceil(total_len, PAGE_SIZE); + + for (i = 0; i < rm->m_nents; ++i) { + sg_set_page(&rm->m_sg[i], + virt_to_page(page_addrs[i]), + PAGE_SIZE, 0); + } + + return rm; +} + +struct rds_message *rds_message_copy_from_user(struct iovec *first_iov, + size_t total_len) +{ + unsigned long to_copy; + unsigned long iov_off; + unsigned long sg_off; + struct rds_message *rm; + struct iovec *iov; + struct scatterlist *sg; + int ret; + + rm = rds_message_alloc(ceil(total_len, PAGE_SIZE), GFP_KERNEL); + if (rm == NULL) { + ret = -ENOMEM; + goto out; + } + + rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); + + /* + * now allocate and copy in the data payload. + */ + sg = rm->m_sg; + iov = first_iov; + iov_off = 0; + sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */ + + while (total_len) { + if (sg_page(sg) == NULL) { + ret = rds_page_remainder_alloc(sg, total_len, + GFP_HIGHUSER); + if (ret) + goto out; + rm->m_nents++; + sg_off = 0; + } + + while (iov_off == iov->iov_len) { + iov_off = 0; + iov++; + } + + to_copy = min(iov->iov_len - iov_off, sg->length - sg_off); + to_copy = min_t(size_t, to_copy, total_len); + + rdsdebug("copying %lu bytes from user iov [%p, %zu] + %lu to " + "sg [%p, %u, %u] + %lu\n", + to_copy, iov->iov_base, iov->iov_len, iov_off, + (void *)sg_page(sg), sg->offset, sg->length, sg_off); + + ret = rds_page_copy_from_user(sg_page(sg), sg->offset + sg_off, + iov->iov_base + iov_off, + to_copy); + if (ret) + goto out; + + iov_off += to_copy; + total_len -= to_copy; + sg_off += to_copy; + + if (sg_off == sg->length) + sg++; + } + + ret = 0; +out: + if (ret) { + if (rm) + rds_message_put(rm); + rm = ERR_PTR(ret); + } + return rm; +} + +int rds_message_inc_copy_to_user(struct rds_incoming *inc, + struct iovec *first_iov, size_t size) +{ + struct rds_message *rm; + struct iovec *iov; + struct scatterlist *sg; + unsigned long to_copy; + unsigned long iov_off; + unsigned long vec_off; + int copied; + int ret; + u32 len; + + rm = container_of(inc, struct rds_message, m_inc); + len = be32_to_cpu(rm->m_inc.i_hdr.h_len); + + iov = first_iov; + iov_off = 0; + sg = rm->m_sg; + vec_off = 0; + copied = 0; + + while (copied < size && copied < len) { + while (iov_off == iov->iov_len) { + iov_off = 0; + iov++; + } + + to_copy = min(iov->iov_len - iov_off, sg->length - vec_off); + to_copy = min_t(size_t, to_copy, size - copied); + to_copy = min_t(unsigned long, to_copy, len - copied); + + rdsdebug("copying %lu bytes to user iov [%p, %zu] + %lu to " + "sg [%p, %u, %u] + %lu\n", + to_copy, iov->iov_base, iov->iov_len, iov_off, + sg_page(sg), sg->offset, sg->length, vec_off); + + ret = rds_page_copy_to_user(sg_page(sg), sg->offset + vec_off, + iov->iov_base + iov_off, + to_copy); + if (ret) { + copied = ret; + break; + } + + iov_off += to_copy; + vec_off += to_copy; + copied += to_copy; + + if (vec_off == sg->length) { + vec_off = 0; + sg++; + } + } + + return copied; +} + +/* + * If the message is still on the send queue, wait until the transport + * is done with it. This is particularly important for RDMA operations. + */ +void rds_message_wait(struct rds_message *rm) +{ + wait_event(rds_message_flush_waitq, + !test_bit(RDS_MSG_MAPPED, &rm->m_flags)); +} + +void rds_message_unmapped(struct rds_message *rm) +{ + clear_bit(RDS_MSG_MAPPED, &rm->m_flags); + if (waitqueue_active(&rds_message_flush_waitq)) + wake_up(&rds_message_flush_waitq); +} + -- cgit v1.2.3