/* * 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 <linux/slab.h> #include <linux/export.h> #include "rds.h" 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); } EXPORT_SYMBOL_GPL(rds_message_addref); /* * 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->data.op_nents; i++) { rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i])); /* XXX will have to put_page for page refs */ __free_page(sg_page(&rm->data.op_sg[i])); } rm->data.op_nents = 0; if (rm->rdma.op_active) rds_rdma_free_op(&rm->rdma); if (rm->rdma.op_rdma_mr) rds_mr_put(rm->rdma.op_rdma_mr); if (rm->atomic.op_active) rds_atomic_free_op(&rm->atomic); if (rm->atomic.op_rdma_mr) rds_mr_put(rm->atomic.op_rdma_mr); } void rds_message_put(struct rds_message *rm) { rdsdebug("put rm %p ref %d\n", rm, atomic_read(&rm->m_refcount)); WARN(!atomic_read(&rm->m_refcount), "danger refcount zero on %p\n", rm); 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); } } EXPORT_SYMBOL_GPL(rds_message_put); 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; } EXPORT_SYMBOL_GPL(rds_message_populate_header); 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; } EXPORT_SYMBOL_GPL(rds_message_add_extension); /* * 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_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)); } EXPORT_SYMBOL_GPL(rds_message_add_rdma_dest_extension); /* * Each rds_message is allocated with extra space for the scatterlist entries * rds ops will need. This is to minimize memory allocation count. Then, each rds op * can grab SGs when initializing its part of the rds_message. */ struct rds_message *rds_message_alloc(unsigned int extra_len, gfp_t gfp) { struct rds_message *rm; if (extra_len > KMALLOC_MAX_SIZE - sizeof(struct rds_message)) return NULL; rm = kzalloc(sizeof(struct rds_message) + extra_len, gfp); if (!rm) goto out; rm->m_used_sgs = 0; rm->m_total_sgs = extra_len / sizeof(struct scatterlist); 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); init_waitqueue_head(&rm->m_flush_wait); out: return rm; } /* * RDS ops use this to grab SG entries from the rm's sg pool. */ struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents) { struct scatterlist *sg_first = (struct scatterlist *) &rm[1]; struct scatterlist *sg_ret; WARN_ON(rm->m_used_sgs + nents > rm->m_total_sgs); WARN_ON(!nents); if (rm->m_used_sgs + nents > rm->m_total_sgs) return NULL; sg_ret = &sg_first[rm->m_used_sgs]; sg_init_table(sg_ret, nents); rm->m_used_sgs += nents; return sg_ret; } struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len) { struct rds_message *rm; unsigned int i; int num_sgs = ceil(total_len, PAGE_SIZE); int extra_bytes = num_sgs * sizeof(struct scatterlist); rm = rds_message_alloc(extra_bytes, GFP_NOWAIT); if (!rm) 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->data.op_nents = ceil(total_len, PAGE_SIZE); rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs); if (!rm->data.op_sg) { rds_message_put(rm); return ERR_PTR(-ENOMEM); } for (i = 0; i < rm->data.op_nents; ++i) { sg_set_page(&rm->data.op_sg[i], virt_to_page(page_addrs[i]), PAGE_SIZE, 0); } return rm; } int rds_message_copy_from_user(struct rds_message *rm, struct iovec *first_iov, size_t total_len) { unsigned long to_copy; unsigned long iov_off; unsigned long sg_off; struct iovec *iov; struct scatterlist *sg; int ret = 0; rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len); /* * now allocate and copy in the data payload. */ sg = rm->data.op_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)) { ret = rds_page_remainder_alloc(sg, total_len, GFP_HIGHUSER); if (ret) goto out; rm->data.op_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++; } out: return ret; } 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->data.op_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_interruptible(rm->m_flush_wait, !test_bit(RDS_MSG_MAPPED, &rm->m_flags)); } void rds_message_unmapped(struct rds_message *rm) { clear_bit(RDS_MSG_MAPPED, &rm->m_flags); wake_up_interruptible(&rm->m_flush_wait); } EXPORT_SYMBOL_GPL(rds_message_unmapped);