[mirror_ubuntu-bionic-kernel.git] / net / rds / message.c

/*
 * 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),
[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);

/*
 * 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, 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;
}

int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from)
{
	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. */

	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);
Commit	Line	Data
7875e18e AG	1	/*
	2	* Copyright (c) 2006 Oracle. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*
	32	*/
	33	#include <linux/kernel.h>
5a0e3ad6	34	#include <linux/slab.h>
bc3b2d7f	35	#include <linux/export.h>
7875e18e AG	36
7875e18e AG	37	#include "rds.h"
7875e18e	38
7875e18e AG	39	static unsigned int rds_exthdr_size[__RDS_EXTHDR_MAX] = {
	40	[RDS_EXTHDR_NONE] = 0,
	41	[RDS_EXTHDR_VERSION] = sizeof(struct rds_ext_header_version),
	42	[RDS_EXTHDR_RDMA] = sizeof(struct rds_ext_header_rdma),
	43	[RDS_EXTHDR_RDMA_DEST] = sizeof(struct rds_ext_header_rdma_dest),
5916e2c1	44	[RDS_EXTHDR_NPATHS] = sizeof(u16),
905dd418	45	[RDS_EXTHDR_GEN_NUM] = sizeof(u32),
7875e18e AG	46	};
	47
	48
	49	void rds_message_addref(struct rds_message *rm)
	50	{
6c5a1c4a RE	51	rdsdebug("addref rm %p ref %d\n", rm, refcount_read(&rm->m_refcount));
6c5a1c4a RE	52	refcount_inc(&rm->m_refcount);
7875e18e	53	}
616b757a	54	EXPORT_SYMBOL_GPL(rds_message_addref);
7875e18e AG	55
	56	/*
	57	* This relies on dma_map_sg() not touching sg[].page during merging.
	58	*/
	59	static void rds_message_purge(struct rds_message *rm)
	60	{
	61	unsigned long i;
	62
	63	if (unlikely(test_bit(RDS_MSG_PAGEVEC, &rm->m_flags)))
	64	return;
	65
6c7cc6e4 AG	66	for (i = 0; i < rm->data.op_nents; i++) {
6c7cc6e4 AG	67	rdsdebug("putting data page %p\n", (void *)sg_page(&rm->data.op_sg[i]));
7875e18e	68	/* XXX will have to put_page for page refs */
6c7cc6e4	69	__free_page(sg_page(&rm->data.op_sg[i]));
7875e18e	70	}
6c7cc6e4	71	rm->data.op_nents = 0;
7875e18e	72
f8b3aaf2 AG	73	if (rm->rdma.op_active)
	74	rds_rdma_free_op(&rm->rdma);
	75	if (rm->rdma.op_rdma_mr)
	76	rds_mr_put(rm->rdma.op_rdma_mr);
d0ab25a8 AG	77
	78	if (rm->atomic.op_active)
	79	rds_atomic_free_op(&rm->atomic);
	80	if (rm->atomic.op_rdma_mr)
	81	rds_mr_put(rm->atomic.op_rdma_mr);
7875e18e	82	}
7875e18e AG	83
	84	void rds_message_put(struct rds_message *rm)
	85	{
6c5a1c4a RE	86	rdsdebug("put rm %p ref %d\n", rm, refcount_read(&rm->m_refcount));
	87	WARN(!refcount_read(&rm->m_refcount), "danger refcount zero on %p\n", rm);
	88	if (refcount_dec_and_test(&rm->m_refcount)) {
7875e18e AG	89	BUG_ON(!list_empty(&rm->m_sock_item));
	90	BUG_ON(!list_empty(&rm->m_conn_item));
	91	rds_message_purge(rm);
	92
	93	kfree(rm);
	94	}
	95	}
616b757a	96	EXPORT_SYMBOL_GPL(rds_message_put);
7875e18e	97
7875e18e AG	98	void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
	99	__be16 dport, u64 seq)
	100	{
	101	hdr->h_flags = 0;
	102	hdr->h_sport = sport;
	103	hdr->h_dport = dport;
	104	hdr->h_sequence = cpu_to_be64(seq);
	105	hdr->h_exthdr[0] = RDS_EXTHDR_NONE;
	106	}
616b757a	107	EXPORT_SYMBOL_GPL(rds_message_populate_header);
7875e18e	108
ff51bf84	109	int rds_message_add_extension(struct rds_header *hdr, unsigned int type,
ff51bf84	110	const void *data, unsigned int len)
7875e18e AG	111	{
	112	unsigned int ext_len = sizeof(u8) + len;
	113	unsigned char *dst;
	114
	115	/* For now, refuse to add more than one extension header */
	116	if (hdr->h_exthdr[0] != RDS_EXTHDR_NONE)
	117	return 0;
	118
f64f9e71	119	if (type >= __RDS_EXTHDR_MAX \|\| len != rds_exthdr_size[type])
7875e18e AG	120	return 0;
	121
	122	if (ext_len >= RDS_HEADER_EXT_SPACE)
	123	return 0;
	124	dst = hdr->h_exthdr;
	125
	126	*dst++ = type;
	127	memcpy(dst, data, len);
	128
	129	dst[len] = RDS_EXTHDR_NONE;
	130	return 1;
	131	}
616b757a	132	EXPORT_SYMBOL_GPL(rds_message_add_extension);
7875e18e AG	133
	134	/*
	135	* If a message has extension headers, retrieve them here.
	136	* Call like this:
	137	*
	138	* unsigned int pos = 0;
	139	*
	140	* while (1) {
	141	* buflen = sizeof(buffer);
	142	* type = rds_message_next_extension(hdr, &pos, buffer, &buflen);
	143	* if (type == RDS_EXTHDR_NONE)
	144	* break;
	145	* ...
	146	* }
	147	*/
	148	int rds_message_next_extension(struct rds_header *hdr,
	149	unsigned int pos, void buf, unsigned int *buflen)
	150	{
	151	unsigned int offset, ext_type, ext_len;
	152	u8 *src = hdr->h_exthdr;
	153
	154	offset = *pos;
	155	if (offset >= RDS_HEADER_EXT_SPACE)
	156	goto none;
	157
	158	/* Get the extension type and length. For now, the
	159	* length is implied by the extension type. */
	160	ext_type = src[offset++];
	161
	162	if (ext_type == RDS_EXTHDR_NONE \|\| ext_type >= __RDS_EXTHDR_MAX)
	163	goto none;
	164	ext_len = rds_exthdr_size[ext_type];
	165	if (offset + ext_len > RDS_HEADER_EXT_SPACE)
	166	goto none;
	167
	168	*pos = offset + ext_len;
	169	if (ext_len < *buflen)
	170	*buflen = ext_len;
	171	memcpy(buf, src + offset, *buflen);
	172	return ext_type;
	173
	174	none:
	175	*pos = RDS_HEADER_EXT_SPACE;
	176	*buflen = 0;
	177	return RDS_EXTHDR_NONE;
	178	}
	179
7875e18e AG	180	int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset)
	181	{
	182	struct rds_ext_header_rdma_dest ext_hdr;
	183
	184	ext_hdr.h_rdma_rkey = cpu_to_be32(r_key);
	185	ext_hdr.h_rdma_offset = cpu_to_be32(offset);
	186	return rds_message_add_extension(hdr, RDS_EXTHDR_RDMA_DEST, &ext_hdr, sizeof(ext_hdr));
	187	}
616b757a	188	EXPORT_SYMBOL_GPL(rds_message_add_rdma_dest_extension);
7875e18e	189
fc445084 AG	190	/*
	191	* Each rds_message is allocated with extra space for the scatterlist entries
	192	* rds ops will need. This is to minimize memory allocation count. Then, each rds op
	193	* can grab SGs when initializing its part of the rds_message.
	194	*/
	195	struct rds_message *rds_message_alloc(unsigned int extra_len, gfp_t gfp)
7875e18e AG	196	{
	197	struct rds_message *rm;
	198
ece6b0a2 CW	199	if (extra_len > KMALLOC_MAX_SIZE - sizeof(struct rds_message))
	200	return NULL;
	201
fc445084	202	rm = kzalloc(sizeof(struct rds_message) + extra_len, gfp);
7875e18e AG	203	if (!rm)
	204	goto out;
	205
fc445084 AG	206	rm->m_used_sgs = 0;
	207	rm->m_total_sgs = extra_len / sizeof(struct scatterlist);
	208
6c5a1c4a	209	refcount_set(&rm->m_refcount, 1);
7875e18e AG	210	INIT_LIST_HEAD(&rm->m_sock_item);
	211	INIT_LIST_HEAD(&rm->m_conn_item);
	212	spin_lock_init(&rm->m_rs_lock);
c83188dc	213	init_waitqueue_head(&rm->m_flush_wait);
7875e18e AG	214
	215	out:
	216	return rm;
	217	}
	218
fc445084 AG	219	/*
	220	* RDS ops use this to grab SG entries from the rm's sg pool.
	221	*/
	222	struct scatterlist rds_message_alloc_sgs(struct rds_message rm, int nents)
	223	{
	224	struct scatterlist sg_first = (struct scatterlist ) &rm[1];
	225	struct scatterlist *sg_ret;
	226
	227	WARN_ON(rm->m_used_sgs + nents > rm->m_total_sgs);
ee4c7b47	228	WARN_ON(!nents);
fc445084	229
d139ff09 AG	230	if (rm->m_used_sgs + nents > rm->m_total_sgs)
	231	return NULL;
	232
fc445084	233	sg_ret = &sg_first[rm->m_used_sgs];
f4dd96f7	234	sg_init_table(sg_ret, nents);
fc445084 AG	235	rm->m_used_sgs += nents;
	236
	237	return sg_ret;
	238	}
	239
7875e18e AG	240	struct rds_message rds_message_map_pages(unsigned long page_addrs, unsigned int total_len)
	241	{
	242	struct rds_message *rm;
	243	unsigned int i;
ff87e97a AG	244	int num_sgs = ceil(total_len, PAGE_SIZE);
ff87e97a AG	245	int extra_bytes = num_sgs * sizeof(struct scatterlist);
7875e18e	246
f2ec76f2	247	rm = rds_message_alloc(extra_bytes, GFP_NOWAIT);
8690bfa1	248	if (!rm)
7875e18e AG	249	return ERR_PTR(-ENOMEM);
	250
	251	set_bit(RDS_MSG_PAGEVEC, &rm->m_flags);
	252	rm->m_inc.i_hdr.h_len = cpu_to_be32(total_len);
6c7cc6e4 AG	253	rm->data.op_nents = ceil(total_len, PAGE_SIZE);
6c7cc6e4 AG	254	rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs);
aa58163a PE	255	if (!rm->data.op_sg) {
aa58163a PE	256	rds_message_put(rm);
d139ff09	257	return ERR_PTR(-ENOMEM);
aa58163a	258	}
7875e18e	259
6c7cc6e4 AG	260	for (i = 0; i < rm->data.op_nents; ++i) {
6c7cc6e4 AG	261	sg_set_page(&rm->data.op_sg[i],
7875e18e AG	262	virt_to_page(page_addrs[i]),
	263	PAGE_SIZE, 0);
	264	}
	265
	266	return rm;
	267	}
	268
083735f4	269	int rds_message_copy_from_user(struct rds_message rm, struct iov_iter from)
7875e18e	270	{
d0a47d32	271	unsigned long to_copy, nbytes;
7875e18e	272	unsigned long sg_off;
7875e18e	273	struct scatterlist *sg;
fc445084	274	int ret = 0;
7875e18e	275
083735f4	276	rm->m_inc.i_hdr.h_len = cpu_to_be32(iov_iter_count(from));
7875e18e AG	277
	278	/*
	279	* now allocate and copy in the data payload.
	280	*/
6c7cc6e4	281	sg = rm->data.op_sg;
7875e18e AG	282	sg_off = 0; /* Dear gcc, sg->page will be null from kzalloc. */
7875e18e AG	283
083735f4	284	while (iov_iter_count(from)) {
8690bfa1	285	if (!sg_page(sg)) {
083735f4	286	ret = rds_page_remainder_alloc(sg, iov_iter_count(from),
7875e18e AG	287	GFP_HIGHUSER);
7875e18e AG	288	if (ret)
083735f4	289	return ret;
6c7cc6e4	290	rm->data.op_nents++;
7875e18e AG	291	sg_off = 0;
	292	}
	293
083735f4 AV	294	to_copy = min_t(unsigned long, iov_iter_count(from),
083735f4 AV	295	sg->length - sg_off);
7875e18e	296
083735f4	297	rds_stats_add(s_copy_from_user, to_copy);
d0a47d32 SV	298	nbytes = copy_page_from_iter(sg_page(sg), sg->offset + sg_off,
	299	to_copy, from);
	300	if (nbytes != to_copy)
083735f4	301	return -EFAULT;
7875e18e	302
7875e18e AG	303	sg_off += to_copy;
	304
	305	if (sg_off == sg->length)
	306	sg++;
	307	}
	308
fc445084	309	return ret;
7875e18e AG	310	}
7875e18e AG	311
c310e72c	312	int rds_message_inc_copy_to_user(struct rds_incoming inc, struct iov_iter to)
7875e18e AG	313	{
7875e18e AG	314	struct rds_message *rm;
7875e18e AG	315	struct scatterlist *sg;
7875e18e AG	316	unsigned long to_copy;
7875e18e AG	317	unsigned long vec_off;
	318	int copied;
	319	int ret;
	320	u32 len;
	321
	322	rm = container_of(inc, struct rds_message, m_inc);
	323	len = be32_to_cpu(rm->m_inc.i_hdr.h_len);
	324
6c7cc6e4	325	sg = rm->data.op_sg;
7875e18e AG	326	vec_off = 0;
	327	copied = 0;
	328
c310e72c	329	while (iov_iter_count(to) && copied < len) {
6ff4a8ad GU	330	to_copy = min_t(unsigned long, iov_iter_count(to),
6ff4a8ad GU	331	sg->length - vec_off);
7875e18e AG	332	to_copy = min_t(unsigned long, to_copy, len - copied);
7875e18e AG	333
c310e72c AV	334	rds_stats_add(s_copy_to_user, to_copy);
	335	ret = copy_page_to_iter(sg_page(sg), sg->offset + vec_off,
	336	to_copy, to);
	337	if (ret != to_copy)
	338	return -EFAULT;
7875e18e	339
7875e18e AG	340	vec_off += to_copy;
	341	copied += to_copy;
	342
	343	if (vec_off == sg->length) {
	344	vec_off = 0;
	345	sg++;
	346	}
	347	}
	348
	349	return copied;
	350	}
	351
	352	/*
	353	* If the message is still on the send queue, wait until the transport
	354	* is done with it. This is particularly important for RDMA operations.
	355	*/
	356	void rds_message_wait(struct rds_message *rm)
	357	{
c83188dc	358	wait_event_interruptible(rm->m_flush_wait,
7875e18e AG	359	!test_bit(RDS_MSG_MAPPED, &rm->m_flags));
	360	}
	361
	362	void rds_message_unmapped(struct rds_message *rm)
	363	{
	364	clear_bit(RDS_MSG_MAPPED, &rm->m_flags);
c83188dc	365	wake_up_interruptible(&rm->m_flush_wait);
7875e18e	366	}
616b757a	367	EXPORT_SYMBOL_GPL(rds_message_unmapped);
7875e18e	368