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-rw-r--r--net/rds/message.c516
1 files changed, 516 insertions, 0 deletions
diff --git a/net/rds/message.c b/net/rds/message.c
new file mode 100644
index 000000000..4b00b1152
--- /dev/null
+++ b/net/rds/message.c
@@ -0,0 +1,516 @@
+/*
+ * 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 <linux/skbuff.h>
+#include <linux/list.h>
+#include <linux/errqueue.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),
+[RDS_EXTHDR_NPATHS] = sizeof(u16),
+[RDS_EXTHDR_GEN_NUM] = sizeof(u32),
+};
+
+void rds_message_addref(struct rds_message *rm)
+{
+ rdsdebug("addref rm %p ref %d\n", rm, refcount_read(&rm->m_refcount));
+ refcount_inc(&rm->m_refcount);
+}
+EXPORT_SYMBOL_GPL(rds_message_addref);
+
+static inline bool rds_zcookie_add(struct rds_msg_zcopy_info *info, u32 cookie)
+{
+ struct rds_zcopy_cookies *ck = &info->zcookies;
+ int ncookies = ck->num;
+
+ if (ncookies == RDS_MAX_ZCOOKIES)
+ return false;
+ ck->cookies[ncookies] = cookie;
+ ck->num = ++ncookies;
+ return true;
+}
+
+static struct rds_msg_zcopy_info *rds_info_from_znotifier(struct rds_znotifier *znotif)
+{
+ return container_of(znotif, struct rds_msg_zcopy_info, znotif);
+}
+
+void rds_notify_msg_zcopy_purge(struct rds_msg_zcopy_queue *q)
+{
+ unsigned long flags;
+ LIST_HEAD(copy);
+ struct rds_msg_zcopy_info *info, *tmp;
+
+ spin_lock_irqsave(&q->lock, flags);
+ list_splice(&q->zcookie_head, &copy);
+ INIT_LIST_HEAD(&q->zcookie_head);
+ spin_unlock_irqrestore(&q->lock, flags);
+
+ list_for_each_entry_safe(info, tmp, &copy, rs_zcookie_next) {
+ list_del(&info->rs_zcookie_next);
+ kfree(info);
+ }
+}
+
+static void rds_rm_zerocopy_callback(struct rds_sock *rs,
+ struct rds_znotifier *znotif)
+{
+ struct rds_msg_zcopy_info *info;
+ struct rds_msg_zcopy_queue *q;
+ u32 cookie = znotif->z_cookie;
+ struct rds_zcopy_cookies *ck;
+ struct list_head *head;
+ unsigned long flags;
+
+ mm_unaccount_pinned_pages(&znotif->z_mmp);
+ q = &rs->rs_zcookie_queue;
+ spin_lock_irqsave(&q->lock, flags);
+ head = &q->zcookie_head;
+ if (!list_empty(head)) {
+ info = list_entry(head, struct rds_msg_zcopy_info,
+ rs_zcookie_next);
+ if (info && rds_zcookie_add(info, cookie)) {
+ spin_unlock_irqrestore(&q->lock, flags);
+ kfree(rds_info_from_znotifier(znotif));
+ /* caller invokes rds_wake_sk_sleep() */
+ return;
+ }
+ }
+
+ info = rds_info_from_znotifier(znotif);
+ ck = &info->zcookies;
+ memset(ck, 0, sizeof(*ck));
+ WARN_ON(!rds_zcookie_add(info, cookie));
+ list_add_tail(&q->zcookie_head, &info->rs_zcookie_next);
+
+ spin_unlock_irqrestore(&q->lock, flags);
+ /* caller invokes rds_wake_sk_sleep() */
+}
+
+/*
+ * This relies on dma_map_sg() not touching sg[].page during merging.
+ */
+static void rds_message_purge(struct rds_message *rm)
+{
+ unsigned long i, flags;
+ bool zcopy = false;
+
+ if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags)))
+ return;
+
+ spin_lock_irqsave(&rm->m_rs_lock, flags);
+ if (rm->m_rs) {
+ struct rds_sock *rs = rm->m_rs;
+
+ if (rm->data.op_mmp_znotifier) {
+ zcopy = true;
+ rds_rm_zerocopy_callback(rs, rm->data.op_mmp_znotifier);
+ rds_wake_sk_sleep(rs);
+ rm->data.op_mmp_znotifier = NULL;
+ }
+ sock_put(rds_rs_to_sk(rs));
+ rm->m_rs = NULL;
+ }
+ spin_unlock_irqrestore(&rm->m_rs_lock, flags);
+
+ for (i = 0; i < rm->data.op_nents; i++) {
+ /* XXX will have to put_page for page refs */
+ if (!zcopy)
+ __free_page(sg_page(&rm->data.op_sg[i]));
+ else
+ put_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, refcount_read(&rm->m_refcount));
+ WARN(!refcount_read(&rm->m_refcount), "danger refcount zero on %p\n", rm);
+ if (refcount_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);
+
+ refcount_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;
+}
+
+static int rds_message_zcopy_from_user(struct rds_message *rm, struct iov_iter *from)
+{
+ struct scatterlist *sg;
+ int ret = 0;
+ int length = iov_iter_count(from);
+ int total_copied = 0;
+ struct rds_msg_zcopy_info *info;
+
+ rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
+
+ /*
+ * now allocate and copy in the data payload.
+ */
+ sg = rm->data.op_sg;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+ INIT_LIST_HEAD(&info->rs_zcookie_next);
+ rm->data.op_mmp_znotifier = &info->znotif;
+ if (mm_account_pinned_pages(&rm->data.op_mmp_znotifier->z_mmp,
+ length)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ while (iov_iter_count(from)) {
+ struct page *pages;
+ size_t start;
+ ssize_t copied;
+
+ copied = iov_iter_get_pages(from, &pages, PAGE_SIZE,
+ 1, &start);
+ if (copied < 0) {
+ struct mmpin *mmp;
+ int i;
+
+ for (i = 0; i < rm->data.op_nents; i++)
+ put_page(sg_page(&rm->data.op_sg[i]));
+ mmp = &rm->data.op_mmp_znotifier->z_mmp;
+ mm_unaccount_pinned_pages(mmp);
+ ret = -EFAULT;
+ goto err;
+ }
+ total_copied += copied;
+ iov_iter_advance(from, copied);
+ length -= copied;
+ sg_set_page(sg, pages, copied, start);
+ rm->data.op_nents++;
+ sg++;
+ }
+ WARN_ON_ONCE(length != 0);
+ return ret;
+err:
+ kfree(info);
+ rm->data.op_mmp_znotifier = NULL;
+ return ret;
+}
+
+int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from,
+ bool zcopy)
+{
+ unsigned long to_copy, nbytes;
+ unsigned long sg_off;
+ struct scatterlist *sg;
+ int ret = 0;
+
+ rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
+
+ /* now allocate and copy in the data payload. */
+ sg = rm->data.op_sg;
+ sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
+
+ if (zcopy)
+ return rds_message_zcopy_from_user(rm, from);
+
+ while (iov_iter_count(from)) {
+ if (!sg_page(sg)) {
+ ret = rds_page_remainder_alloc(sg, iov_iter_count(from),
+ GFP_HIGHUSER);
+ if (ret)
+ return ret;
+ rm->data.op_nents++;
+ sg_off = 0;
+ }
+
+ to_copy = min_t(unsigned long, iov_iter_count(from),
+ sg->length - sg_off);
+
+ rds_stats_add(s_copy_from_user, to_copy);
+ nbytes = copy_page_from_iter(sg_page(sg), sg->offset + sg_off,
+ to_copy, from);
+ if (nbytes != to_copy)
+ return -EFAULT;
+
+ sg_off += to_copy;
+
+ if (sg_off == sg->length)
+ sg++;
+ }
+
+ return ret;
+}
+
+int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to)
+{
+ struct rds_message *rm;
+ struct scatterlist *sg;
+ unsigned long to_copy;
+ 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);
+
+ sg = rm->data.op_sg;
+ vec_off = 0;
+ copied = 0;
+
+ while (iov_iter_count(to) && copied < len) {
+ to_copy = min_t(unsigned long, iov_iter_count(to),
+ sg->length - vec_off);
+ to_copy = min_t(unsigned long, to_copy, len - copied);
+
+ rds_stats_add(s_copy_to_user, to_copy);
+ ret = copy_page_to_iter(sg_page(sg), sg->offset + vec_off,
+ to_copy, to);
+ if (ret != to_copy)
+ return -EFAULT;
+
+ 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);
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