diff options
| -rw-r--r-- | net/rds/message.c | 402 | ||||
| -rw-r--r-- | net/rds/page.c | 221 |
2 files changed, 623 insertions, 0 deletions
diff --git a/net/rds/message.c b/net/rds/message.c new file mode 100644 index 0000000..5a15dc8 --- /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 <linux/kernel.h> + +#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); +} + diff --git a/net/rds/page.c b/net/rds/page.c new file mode 100644 index 0000000..c460743 --- /dev/null +++ b/net/rds/page.c @@ -0,0 +1,221 @@ +/* + * 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 <linux/highmem.h> + +#include "rds.h" + +struct rds_page_remainder { + struct page *r_page; + unsigned long r_offset; +}; + +DEFINE_PER_CPU(struct rds_page_remainder, rds_page_remainders) ____cacheline_aligned; + +/* + * returns 0 on success or -errno on failure. + * + * We don't have to worry about flush_dcache_page() as this only works + * with private pages. If, say, we were to do directed receive to pinned + * user pages we'd have to worry more about cache coherence. (Though + * the flush_dcache_page() in get_user_pages() would probably be enough). + */ +int rds_page_copy_user(struct page *page, unsigned long offset, + void __user *ptr, unsigned long bytes, + int to_user) +{ + unsigned long ret; + void *addr; + + if (to_user) + rds_stats_add(s_copy_to_user, bytes); + else + rds_stats_add(s_copy_from_user, bytes); + + addr = kmap_atomic(page, KM_USER0); + if (to_user) + ret = __copy_to_user_inatomic(ptr, addr + offset, bytes); + else + ret = __copy_from_user_inatomic(addr + offset, ptr, bytes); + kunmap_atomic(addr, KM_USER0); + + if (ret) { + addr = kmap(page); + if (to_user) + ret = copy_to_user(ptr, addr + offset, bytes); + else + ret = copy_from_user(addr + offset, ptr, bytes); + kunmap(page); + if (ret) + return -EFAULT; + } + + return 0; +} + +/* + * Message allocation uses this to build up regions of a message. + * + * @bytes - the number of bytes needed. + * @gfp - the waiting behaviour of the allocation + * + * @gfp is always ored with __GFP_HIGHMEM. Callers must be prepared to + * kmap the pages, etc. + * + * If @bytes is at least a full page then this just returns a page from + * alloc_page(). + * + * If @bytes is a partial page then this stores the unused region of the + * page in a per-cpu structure. Future partial-page allocations may be + * satisfied from that cached region. This lets us waste less memory on + * small allocations with minimal complexity. It works because the transmit + * path passes read-only page regions down to devices. They hold a page + * reference until they are done with the region. + */ +int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes, + gfp_t gfp) +{ + struct rds_page_remainder *rem; + unsigned long flags; + struct page *page; + int ret; + + gfp |= __GFP_HIGHMEM; + + /* jump straight to allocation if we're trying for a huge page */ + if (bytes >= PAGE_SIZE) { + page = alloc_page(gfp); + if (page == NULL) { + ret = -ENOMEM; + } else { + sg_set_page(scat, page, PAGE_SIZE, 0); + ret = 0; + } + goto out; + } + + rem = &per_cpu(rds_page_remainders, get_cpu()); + local_irq_save(flags); + + while (1) { + /* avoid a tiny region getting stuck by tossing it */ + if (rem->r_page && bytes > (PAGE_SIZE - rem->r_offset)) { + rds_stats_inc(s_page_remainder_miss); + __free_page(rem->r_page); + rem->r_page = NULL; + } + + /* hand out a fragment from the cached page */ + if (rem->r_page && bytes <= (PAGE_SIZE - rem->r_offset)) { + sg_set_page(scat, rem->r_page, bytes, rem->r_offset); + get_page(sg_page(scat)); + + if (rem->r_offset != 0) + rds_stats_inc(s_page_remainder_hit); + + rem->r_offset += bytes; + if (rem->r_offset == PAGE_SIZE) { + __free_page(rem->r_page); + rem->r_page = NULL; + } + ret = 0; + break; + } + + /* alloc if there is nothing for us to use */ + local_irq_restore(flags); + put_cpu(); + + page = alloc_page(gfp); + + rem = &per_cpu(rds_page_remainders, get_cpu()); + local_irq_save(flags); + + if (page == NULL) { + ret = -ENOMEM; + break; + } + + /* did someone race to fill the remainder before us? */ + if (rem->r_page) { + __free_page(page); + continue; + } + + /* otherwise install our page and loop around to alloc */ + rem->r_page = page; + rem->r_offset = 0; + } + + local_irq_restore(flags); + put_cpu(); +out: + rdsdebug("bytes %lu ret %d %p %u %u\n", bytes, ret, + ret ? NULL : sg_page(scat), ret ? 0 : scat->offset, + ret ? 0 : scat->length); + return ret; +} + +static int rds_page_remainder_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + struct rds_page_remainder *rem; + long cpu = (long)hcpu; + + rem = &per_cpu(rds_page_remainders, cpu); + + rdsdebug("cpu %ld action 0x%lx\n", cpu, action); + + switch (action) { + case CPU_DEAD: + if (rem->r_page) + __free_page(rem->r_page); + rem->r_page = NULL; + break; + } + + return 0; +} + +static struct notifier_block rds_page_remainder_nb = { + .notifier_call = rds_page_remainder_cpu_notify, +}; + +void rds_page_exit(void) +{ + int i; + + for_each_possible_cpu(i) + rds_page_remainder_cpu_notify(&rds_page_remainder_nb, + (unsigned long)CPU_DEAD, + (void *)(long)i); +} |
