kvj
/
linux-zen-server
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
linux-zen-server/fs/cifs/smbdirect.c

2612 lines
73 KiB
C
Raw Permalink Normal View History

Initial commit
2023-08-30 17:53:23 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017, Microsoft Corporation.
*
* Author(s): Long Li <longli@microsoft.com>
*/
#include <linux/module.h>
#include <linux/highmem.h>
#include "smbdirect.h"
#include "cifs_debug.h"
#include "cifsproto.h"
#include "smb2proto.h"
static struct smbd_response *get_empty_queue_buffer(
struct smbd_connection *info);
static struct smbd_response *get_receive_buffer(
struct smbd_connection *info);
static void put_receive_buffer(
struct smbd_connection *info,
struct smbd_response *response);
static int allocate_receive_buffers(struct smbd_connection *info, int num_buf);
static void destroy_receive_buffers(struct smbd_connection *info);
static void put_empty_packet(
struct smbd_connection *info, struct smbd_response *response);
static void enqueue_reassembly(
struct smbd_connection *info,
struct smbd_response *response, int data_length);
static struct smbd_response *_get_first_reassembly(
struct smbd_connection *info);
static int smbd_post_recv(
struct smbd_connection *info,
struct smbd_response *response);
static int smbd_post_send_empty(struct smbd_connection *info);
static void destroy_mr_list(struct smbd_connection *info);
static int allocate_mr_list(struct smbd_connection *info);
struct smb_extract_to_rdma {
struct ib_sge *sge;
unsigned int nr_sge;
unsigned int max_sge;
struct ib_device *device;
u32 local_dma_lkey;
enum dma_data_direction direction;
};
static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len,
struct smb_extract_to_rdma *rdma);
/* SMBD version number */
#define SMBD_V1 0x0100
/* Port numbers for SMBD transport */
#define SMB_PORT 445
#define SMBD_PORT 5445
/* Address lookup and resolve timeout in ms */
#define RDMA_RESOLVE_TIMEOUT 5000
/* SMBD negotiation timeout in seconds */
#define SMBD_NEGOTIATE_TIMEOUT 120
/* SMBD minimum receive size and fragmented sized defined in [MS-SMBD] */
#define SMBD_MIN_RECEIVE_SIZE 128
#define SMBD_MIN_FRAGMENTED_SIZE 131072
/*
* Default maximum number of RDMA read/write outstanding on this connection
* This value is possibly decreased during QP creation on hardware limit
*/
#define SMBD_CM_RESPONDER_RESOURCES 32
/* Maximum number of retries on data transfer operations */
#define SMBD_CM_RETRY 6
/* No need to retry on Receiver Not Ready since SMBD manages credits */
#define SMBD_CM_RNR_RETRY 0
/*
* User configurable initial values per SMBD transport connection
* as defined in [MS-SMBD] 3.1.1.1
* Those may change after a SMBD negotiation
*/
/* The local peer's maximum number of credits to grant to the peer */
int smbd_receive_credit_max = 255;
/* The remote peer's credit request of local peer */
int smbd_send_credit_target = 255;
/* The maximum single message size can be sent to remote peer */
int smbd_max_send_size = 1364;
/* The maximum fragmented upper-layer payload receive size supported */
int smbd_max_fragmented_recv_size = 1024 * 1024;
/* The maximum single-message size which can be received */
int smbd_max_receive_size = 1364;
/* The timeout to initiate send of a keepalive message on idle */
int smbd_keep_alive_interval = 120;
/*
* User configurable initial values for RDMA transport
* The actual values used may be lower and are limited to hardware capabilities
*/
/* Default maximum number of pages in a single RDMA write/read */
int smbd_max_frmr_depth = 2048;
/* If payload is less than this byte, use RDMA send/recv not read/write */
int rdma_readwrite_threshold = 4096;
/* Transport logging functions
* Logging are defined as classes. They can be OR'ed to define the actual
* logging level via module parameter smbd_logging_class
* e.g. cifs.smbd_logging_class=0xa0 will log all log_rdma_recv() and
* log_rdma_event()
*/
#define LOG_OUTGOING 0x1
#define LOG_INCOMING 0x2
#define LOG_READ 0x4
#define LOG_WRITE 0x8
#define LOG_RDMA_SEND 0x10
#define LOG_RDMA_RECV 0x20
#define LOG_KEEP_ALIVE 0x40
#define LOG_RDMA_EVENT 0x80
#define LOG_RDMA_MR 0x100
static unsigned int smbd_logging_class;
module_param(smbd_logging_class, uint, 0644);
MODULE_PARM_DESC(smbd_logging_class,
"Logging class for SMBD transport 0x0 to 0x100");
#define ERR 0x0
#define INFO 0x1
static unsigned int smbd_logging_level = ERR;
module_param(smbd_logging_level, uint, 0644);
MODULE_PARM_DESC(smbd_logging_level,
"Logging level for SMBD transport, 0 (default): error, 1: info");
#define log_rdma(level, class, fmt, args...) \
do { \
if (level <= smbd_logging_level || class & smbd_logging_class) \
cifs_dbg(VFS, "%s:%d " fmt, __func__, __LINE__, ##args);\
} while (0)
#define log_outgoing(level, fmt, args...) \
log_rdma(level, LOG_OUTGOING, fmt, ##args)
#define log_incoming(level, fmt, args...) \
log_rdma(level, LOG_INCOMING, fmt, ##args)
#define log_read(level, fmt, args...) log_rdma(level, LOG_READ, fmt, ##args)
#define log_write(level, fmt, args...) log_rdma(level, LOG_WRITE, fmt, ##args)
#define log_rdma_send(level, fmt, args...) \
log_rdma(level, LOG_RDMA_SEND, fmt, ##args)
#define log_rdma_recv(level, fmt, args...) \
log_rdma(level, LOG_RDMA_RECV, fmt, ##args)
#define log_keep_alive(level, fmt, args...) \
log_rdma(level, LOG_KEEP_ALIVE, fmt, ##args)
#define log_rdma_event(level, fmt, args...) \
log_rdma(level, LOG_RDMA_EVENT, fmt, ##args)
#define log_rdma_mr(level, fmt, args...) \
log_rdma(level, LOG_RDMA_MR, fmt, ##args)
static void smbd_disconnect_rdma_work(struct work_struct *work)
{
struct smbd_connection *info =
container_of(work, struct smbd_connection, disconnect_work);
if (info->transport_status == SMBD_CONNECTED) {
info->transport_status = SMBD_DISCONNECTING;
rdma_disconnect(info->id);
}
}
static void smbd_disconnect_rdma_connection(struct smbd_connection *info)
{
queue_work(info->workqueue, &info->disconnect_work);
}
/* Upcall from RDMA CM */
static int smbd_conn_upcall(
struct rdma_cm_id *id, struct rdma_cm_event *event)
{
struct smbd_connection *info = id->context;
log_rdma_event(INFO, "event=%d status=%d\n",
event->event, event->status);
switch (event->event) {
case RDMA_CM_EVENT_ADDR_RESOLVED:
case RDMA_CM_EVENT_ROUTE_RESOLVED:
info->ri_rc = 0;
complete(&info->ri_done);
break;
case RDMA_CM_EVENT_ADDR_ERROR:
info->ri_rc = -EHOSTUNREACH;
complete(&info->ri_done);
break;
case RDMA_CM_EVENT_ROUTE_ERROR:
info->ri_rc = -ENETUNREACH;
complete(&info->ri_done);
break;
case RDMA_CM_EVENT_ESTABLISHED:
log_rdma_event(INFO, "connected event=%d\n", event->event);
info->transport_status = SMBD_CONNECTED;
wake_up_interruptible(&info->conn_wait);
break;
case RDMA_CM_EVENT_CONNECT_ERROR:
case RDMA_CM_EVENT_UNREACHABLE:
case RDMA_CM_EVENT_REJECTED:
log_rdma_event(INFO, "connecting failed event=%d\n", event->event);
info->transport_status = SMBD_DISCONNECTED;
wake_up_interruptible(&info->conn_wait);
break;
case RDMA_CM_EVENT_DEVICE_REMOVAL:
case RDMA_CM_EVENT_DISCONNECTED:
/* This happenes when we fail the negotiation */
if (info->transport_status == SMBD_NEGOTIATE_FAILED) {
info->transport_status = SMBD_DISCONNECTED;
wake_up(&info->conn_wait);
break;
}
info->transport_status = SMBD_DISCONNECTED;
wake_up_interruptible(&info->disconn_wait);
wake_up_interruptible(&info->wait_reassembly_queue);
wake_up_interruptible_all(&info->wait_send_queue);
break;
default:
break;
}
return 0;
}
/* Upcall from RDMA QP */
static void
smbd_qp_async_error_upcall(struct ib_event *event, void *context)
{
struct smbd_connection *info = context;
log_rdma_event(ERR, "%s on device %s info %p\n",
ib_event_msg(event->event), event->device->name, info);
switch (event->event) {
case IB_EVENT_CQ_ERR:
case IB_EVENT_QP_FATAL:
smbd_disconnect_rdma_connection(info);
break;
default:
break;
}
}
static inline void *smbd_request_payload(struct smbd_request *request)
{
return (void *)request->packet;
}
static inline void *smbd_response_payload(struct smbd_response *response)
{
return (void *)response->packet;
}
/* Called when a RDMA send is done */
static void send_done(struct ib_cq *cq, struct ib_wc *wc)
{
int i;
struct smbd_request *request =
container_of(wc->wr_cqe, struct smbd_request, cqe);
log_rdma_send(INFO, "smbd_request 0x%p completed wc->status=%d\n",
request, wc->status);
if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_SEND) {
log_rdma_send(ERR, "wc->status=%d wc->opcode=%d\n",
wc->status, wc->opcode);
smbd_disconnect_rdma_connection(request->info);
}
for (i = 0; i < request->num_sge; i++)
ib_dma_unmap_single(request->info->id->device,
request->sge[i].addr,
request->sge[i].length,
DMA_TO_DEVICE);
if (atomic_dec_and_test(&request->info->send_pending))
wake_up(&request->info->wait_send_pending);
wake_up(&request->info->wait_post_send);
mempool_free(request, request->info->request_mempool);
}
static void dump_smbd_negotiate_resp(struct smbd_negotiate_resp *resp)
{
log_rdma_event(INFO, "resp message min_version %u max_version %u negotiated_version %u credits_requested %u credits_granted %u status %u max_readwrite_size %u preferred_send_size %u max_receive_size %u max_fragmented_size %u\n",
resp->min_version, resp->max_version,
resp->negotiated_version, resp->credits_requested,
resp->credits_granted, resp->status,
resp->max_readwrite_size, resp->preferred_send_size,
resp->max_receive_size, resp->max_fragmented_size);
}
/*
* Process a negotiation response message, according to [MS-SMBD]3.1.5.7
* response, packet_length: the negotiation response message
* return value: true if negotiation is a success, false if failed
*/
static bool process_negotiation_response(
struct smbd_response *response, int packet_length)
{
struct smbd_connection *info = response->info;
struct smbd_negotiate_resp *packet = smbd_response_payload(response);
if (packet_length < sizeof(struct smbd_negotiate_resp)) {
log_rdma_event(ERR,
"error: packet_length=%d\n", packet_length);
return false;
}
if (le16_to_cpu(packet->negotiated_version) != SMBD_V1) {
log_rdma_event(ERR, "error: negotiated_version=%x\n",
le16_to_cpu(packet->negotiated_version));
return false;
}
info->protocol = le16_to_cpu(packet->negotiated_version);
if (packet->credits_requested == 0) {
log_rdma_event(ERR, "error: credits_requested==0\n");
return false;
}
info->receive_credit_target = le16_to_cpu(packet->credits_requested);
if (packet->credits_granted == 0) {
log_rdma_event(ERR, "error: credits_granted==0\n");
return false;
}
atomic_set(&info->send_credits, le16_to_cpu(packet->credits_granted));
atomic_set(&info->receive_credits, 0);
if (le32_to_cpu(packet->preferred_send_size) > info->max_receive_size) {
log_rdma_event(ERR, "error: preferred_send_size=%d\n",
le32_to_cpu(packet->preferred_send_size));
return false;
}
info->max_receive_size = le32_to_cpu(packet->preferred_send_size);
if (le32_to_cpu(packet->max_receive_size) < SMBD_MIN_RECEIVE_SIZE) {
log_rdma_event(ERR, "error: max_receive_size=%d\n",
le32_to_cpu(packet->max_receive_size));
return false;
}
info->max_send_size = min_t(int, info->max_send_size,
le32_to_cpu(packet->max_receive_size));
if (le32_to_cpu(packet->max_fragmented_size) <
SMBD_MIN_FRAGMENTED_SIZE) {
log_rdma_event(ERR, "error: max_fragmented_size=%d\n",
le32_to_cpu(packet->max_fragmented_size));
return false;
}
info->max_fragmented_send_size =
le32_to_cpu(packet->max_fragmented_size);
info->rdma_readwrite_threshold =
rdma_readwrite_threshold > info->max_fragmented_send_size ?
info->max_fragmented_send_size :
rdma_readwrite_threshold;
info->max_readwrite_size = min_t(u32,
le32_to_cpu(packet->max_readwrite_size),
info->max_frmr_depth * PAGE_SIZE);
info->max_frmr_depth = info->max_readwrite_size / PAGE_SIZE;
return true;
}
static void smbd_post_send_credits(struct work_struct *work)
{
int ret = 0;
int use_receive_queue = 1;
int rc;
struct smbd_response *response;
struct smbd_connection *info =
container_of(work, struct smbd_connection,
post_send_credits_work);
if (info->transport_status != SMBD_CONNECTED) {
wake_up(&info->wait_receive_queues);
return;
}
if (info->receive_credit_target >
atomic_read(&info->receive_credits)) {
while (true) {
if (use_receive_queue)
response = get_receive_buffer(info);
else
response = get_empty_queue_buffer(info);
if (!response) {
/* now switch to emtpy packet queue */
if (use_receive_queue) {
use_receive_queue = 0;
continue;
} else
break;
}
response->type = SMBD_TRANSFER_DATA;
response->first_segment = false;
rc = smbd_post_recv(info, response);
if (rc) {
log_rdma_recv(ERR,
"post_recv failed rc=%d\n", rc);
put_receive_buffer(info, response);
break;
}
ret++;
}
}
spin_lock(&info->lock_new_credits_offered);
info->new_credits_offered += ret;
spin_unlock(&info->lock_new_credits_offered);
/* Promptly send an immediate packet as defined in [MS-SMBD] 3.1.1.1 */
info->send_immediate = true;
if (atomic_read(&info->receive_credits) <
info->receive_credit_target - 1) {
if (info->keep_alive_requested == KEEP_ALIVE_PENDING ||
info->send_immediate) {
log_keep_alive(INFO, "send an empty message\n");
smbd_post_send_empty(info);
}
}
}
/* Called from softirq, when recv is done */
static void recv_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct smbd_data_transfer *data_transfer;
struct smbd_response *response =
container_of(wc->wr_cqe, struct smbd_response, cqe);
struct smbd_connection *info = response->info;
int data_length = 0;
log_rdma_recv(INFO, "response=0x%p type=%d wc status=%d wc opcode %d byte_len=%d pkey_index=%u\n",
response, response->type, wc->status, wc->opcode,
wc->byte_len, wc->pkey_index);
if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_RECV) {
log_rdma_recv(INFO, "wc->status=%d opcode=%d\n",
wc->status, wc->opcode);
smbd_disconnect_rdma_connection(info);
goto error;
}
ib_dma_sync_single_for_cpu(
wc->qp->device,
response->sge.addr,
response->sge.length,
DMA_FROM_DEVICE);
switch (response->type) {
/* SMBD negotiation response */
case SMBD_NEGOTIATE_RESP:
dump_smbd_negotiate_resp(smbd_response_payload(response));
info->full_packet_received = true;
info->negotiate_done =
process_negotiation_response(response, wc->byte_len);
complete(&info->negotiate_completion);
break;
/* SMBD data transfer packet */
case SMBD_TRANSFER_DATA:
data_transfer = smbd_response_payload(response);
data_length = le32_to_cpu(data_transfer->data_length);
/*
* If this is a packet with data playload place the data in
* reassembly queue and wake up the reading thread
*/
if (data_length) {
if (info->full_packet_received)
response->first_segment = true;
if (le32_to_cpu(data_transfer->remaining_data_length))
info->full_packet_received = false;
else
info->full_packet_received = true;
enqueue_reassembly(
info,
response,
data_length);
} else
put_empty_packet(info, response);
if (data_length)
wake_up_interruptible(&info->wait_reassembly_queue);
atomic_dec(&info->receive_credits);
info->receive_credit_target =
le16_to_cpu(data_transfer->credits_requested);
if (le16_to_cpu(data_transfer->credits_granted)) {
atomic_add(le16_to_cpu(data_transfer->credits_granted),
&info->send_credits);
/*
* We have new send credits granted from remote peer
* If any sender is waiting for credits, unblock it
*/
wake_up_interruptible(&info->wait_send_queue);
}
log_incoming(INFO, "data flags %d data_offset %d data_length %d remaining_data_length %d\n",
le16_to_cpu(data_transfer->flags),
le32_to_cpu(data_transfer->data_offset),
le32_to_cpu(data_transfer->data_length),
le32_to_cpu(data_transfer->remaining_data_length));
/* Send a KEEP_ALIVE response right away if requested */
info->keep_alive_requested = KEEP_ALIVE_NONE;
if (le16_to_cpu(data_transfer->flags) &
SMB_DIRECT_RESPONSE_REQUESTED) {
info->keep_alive_requested = KEEP_ALIVE_PENDING;
}
return;
default:
log_rdma_recv(ERR,
"unexpected response type=%d\n", response->type);
}
error:
put_receive_buffer(info, response);
}
static struct rdma_cm_id *smbd_create_id(
struct smbd_connection *info,
struct sockaddr *dstaddr, int port)
{
struct rdma_cm_id *id;
int rc;
__be16 *sport;
id = rdma_create_id(&init_net, smbd_conn_upcall, info,
RDMA_PS_TCP, IB_QPT_RC);
if (IS_ERR(id)) {
rc = PTR_ERR(id);
log_rdma_event(ERR, "rdma_create_id() failed %i\n", rc);
return id;
}
if (dstaddr->sa_family == AF_INET6)
sport = &((struct sockaddr_in6 *)dstaddr)->sin6_port;
else
sport = &((struct sockaddr_in *)dstaddr)->sin_port;
*sport = htons(port);
init_completion(&info->ri_done);
info->ri_rc = -ETIMEDOUT;
rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)dstaddr,
RDMA_RESOLVE_TIMEOUT);
if (rc) {
log_rdma_event(ERR, "rdma_resolve_addr() failed %i\n", rc);
goto out;
}
rc = wait_for_completion_interruptible_timeout(
&info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
/* e.g. if interrupted returns -ERESTARTSYS */
if (rc < 0) {
log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
goto out;
}
rc = info->ri_rc;
if (rc) {
log_rdma_event(ERR, "rdma_resolve_addr() completed %i\n", rc);
goto out;
}
info->ri_rc = -ETIMEDOUT;
rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
if (rc) {
log_rdma_event(ERR, "rdma_resolve_route() failed %i\n", rc);
goto out;
}
rc = wait_for_completion_interruptible_timeout(
&info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
/* e.g. if interrupted returns -ERESTARTSYS */
if (rc < 0) {
log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
goto out;
}
rc = info->ri_rc;
if (rc) {
log_rdma_event(ERR, "rdma_resolve_route() completed %i\n", rc);
goto out;
}
return id;
out:
rdma_destroy_id(id);
return ERR_PTR(rc);
}
/*
* Test if FRWR (Fast Registration Work Requests) is supported on the device
* This implementation requries FRWR on RDMA read/write
* return value: true if it is supported
*/
static bool frwr_is_supported(struct ib_device_attr *attrs)
{
if (!(attrs->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
return false;
if (attrs->max_fast_reg_page_list_len == 0)
return false;
return true;
}
static int smbd_ia_open(
struct smbd_connection *info,
struct sockaddr *dstaddr, int port)
{
int rc;
info->id = smbd_create_id(info, dstaddr, port);
if (IS_ERR(info->id)) {
rc = PTR_ERR(info->id);
goto out1;
}
if (!frwr_is_supported(&info->id->device->attrs)) {
log_rdma_event(ERR, "Fast Registration Work Requests (FRWR) is not supported\n");
log_rdma_event(ERR, "Device capability flags = %llx max_fast_reg_page_list_len = %u\n",
info->id->device->attrs.device_cap_flags,
info->id->device->attrs.max_fast_reg_page_list_len);
rc = -EPROTONOSUPPORT;
goto out2;
}
info->max_frmr_depth = min_t(int,
smbd_max_frmr_depth,
info->id->device->attrs.max_fast_reg_page_list_len);
info->mr_type = IB_MR_TYPE_MEM_REG;
if (info->id->device->attrs.kernel_cap_flags & IBK_SG_GAPS_REG)
info->mr_type = IB_MR_TYPE_SG_GAPS;
info->pd = ib_alloc_pd(info->id->device, 0);
if (IS_ERR(info->pd)) {
rc = PTR_ERR(info->pd);
log_rdma_event(ERR, "ib_alloc_pd() returned %d\n", rc);
goto out2;
}
return 0;
out2:
rdma_destroy_id(info->id);
info->id = NULL;
out1:
return rc;
}
/*
* Send a negotiation request message to the peer
* The negotiation procedure is in [MS-SMBD] 3.1.5.2 and 3.1.5.3
* After negotiation, the transport is connected and ready for
* carrying upper layer SMB payload
*/
static int smbd_post_send_negotiate_req(struct smbd_connection *info)
{
struct ib_send_wr send_wr;
int rc = -ENOMEM;
struct smbd_request *request;
struct smbd_negotiate_req *packet;
request = mempool_alloc(info->request_mempool, GFP_KERNEL);
if (!request)
return rc;
request->info = info;
packet = smbd_request_payload(request);
packet->min_version = cpu_to_le16(SMBD_V1);
packet->max_version = cpu_to_le16(SMBD_V1);
packet->reserved = 0;
packet->credits_requested = cpu_to_le16(info->send_credit_target);
packet->preferred_send_size = cpu_to_le32(info->max_send_size);
packet->max_receive_size = cpu_to_le32(info->max_receive_size);
packet->max_fragmented_size =
cpu_to_le32(info->max_fragmented_recv_size);
request->num_sge = 1;
request->sge[0].addr = ib_dma_map_single(
info->id->device, (void *)packet,
sizeof(*packet), DMA_TO_DEVICE);
if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
rc = -EIO;
goto dma_mapping_failed;
}
request->sge[0].length = sizeof(*packet);
request->sge[0].lkey = info->pd->local_dma_lkey;
ib_dma_sync_single_for_device(
info->id->device, request->sge[0].addr,
request->sge[0].length, DMA_TO_DEVICE);
request->cqe.done = send_done;
send_wr.next = NULL;
send_wr.wr_cqe = &request->cqe;
send_wr.sg_list = request->sge;
send_wr.num_sge = request->num_sge;
send_wr.opcode = IB_WR_SEND;
send_wr.send_flags = IB_SEND_SIGNALED;
log_rdma_send(INFO, "sge addr=0x%llx length=%u lkey=0x%x\n",
request->sge[0].addr,
request->sge[0].length, request->sge[0].lkey);
atomic_inc(&info->send_pending);
rc = ib_post_send(info->id->qp, &send_wr, NULL);
if (!rc)
return 0;
/* if we reach here, post send failed */
log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
atomic_dec(&info->send_pending);
ib_dma_unmap_single(info->id->device, request->sge[0].addr,
request->sge[0].length, DMA_TO_DEVICE);
smbd_disconnect_rdma_connection(info);
dma_mapping_failed:
mempool_free(request, info->request_mempool);
return rc;
}
/*
* Extend the credits to remote peer
* This implements [MS-SMBD] 3.1.5.9
* The idea is that we should extend credits to remote peer as quickly as
* it's allowed, to maintain data flow. We allocate as much receive
* buffer as possible, and extend the receive credits to remote peer
* return value: the new credtis being granted.
*/
static int manage_credits_prior_sending(struct smbd_connection *info)
{
int new_credits;
spin_lock(&info->lock_new_credits_offered);
new_credits = info->new_credits_offered;
info->new_credits_offered = 0;
spin_unlock(&info->lock_new_credits_offered);
return new_credits;
}
/*
* Check if we need to send a KEEP_ALIVE message
* The idle connection timer triggers a KEEP_ALIVE message when expires
* SMB_DIRECT_RESPONSE_REQUESTED is set in the message flag to have peer send
* back a response.
* return value:
* 1 if SMB_DIRECT_RESPONSE_REQUESTED needs to be set
* 0: otherwise
*/
static int manage_keep_alive_before_sending(struct smbd_connection *info)
{
if (info->keep_alive_requested == KEEP_ALIVE_PENDING) {
info->keep_alive_requested = KEEP_ALIVE_SENT;
return 1;
}
return 0;
}
/* Post the send request */
static int smbd_post_send(struct smbd_connection *info,
struct smbd_request *request)
{
struct ib_send_wr send_wr;
int rc, i;
for (i = 0; i < request->num_sge; i++) {
log_rdma_send(INFO,
"rdma_request sge[%d] addr=0x%llx length=%u\n",
i, request->sge[i].addr, request->sge[i].length);
ib_dma_sync_single_for_device(
info->id->device,
request->sge[i].addr,
request->sge[i].length,
DMA_TO_DEVICE);
}
request->cqe.done = send_done;
send_wr.next = NULL;
send_wr.wr_cqe = &request->cqe;
send_wr.sg_list = request->sge;
send_wr.num_sge = request->num_sge;
send_wr.opcode = IB_WR_SEND;
send_wr.send_flags = IB_SEND_SIGNALED;
rc = ib_post_send(info->id->qp, &send_wr, NULL);
if (rc) {
log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
smbd_disconnect_rdma_connection(info);
rc = -EAGAIN;
} else
/* Reset timer for idle connection after packet is sent */
mod_delayed_work(info->workqueue, &info->idle_timer_work,
info->keep_alive_interval*HZ);
return rc;
}
static int smbd_post_send_iter(struct smbd_connection *info,
struct iov_iter *iter,
int *_remaining_data_length)
{
int i, rc;
int header_length;
int data_length;
struct smbd_request *request;
struct smbd_data_transfer *packet;
int new_credits = 0;
wait_credit:
/* Wait for send credits. A SMBD packet needs one credit */
rc = wait_event_interruptible(info->wait_send_queue,
atomic_read(&info->send_credits) > 0 ||
info->transport_status != SMBD_CONNECTED);
if (rc)
goto err_wait_credit;
if (info->transport_status != SMBD_CONNECTED) {
log_outgoing(ERR, "disconnected not sending on wait_credit\n");
rc = -EAGAIN;
goto err_wait_credit;
}
if (unlikely(atomic_dec_return(&info->send_credits) < 0)) {
atomic_inc(&info->send_credits);
goto wait_credit;
}
wait_send_queue:
wait_event(info->wait_post_send,
atomic_read(&info->send_pending) < info->send_credit_target ||
info->transport_status != SMBD_CONNECTED);
if (info->transport_status != SMBD_CONNECTED) {
log_outgoing(ERR, "disconnected not sending on wait_send_queue\n");
rc = -EAGAIN;
goto err_wait_send_queue;
}
if (unlikely(atomic_inc_return(&info->send_pending) >
info->send_credit_target)) {
atomic_dec(&info->send_pending);
goto wait_send_queue;
}
request = mempool_alloc(info->request_mempool, GFP_KERNEL);
if (!request) {
rc = -ENOMEM;
goto err_alloc;
}
request->info = info;
memset(request->sge, 0, sizeof(request->sge));
/* Fill in the data payload to find out how much data we can add */
if (iter) {
struct smb_extract_to_rdma extract = {
.nr_sge = 1,
.max_sge = SMBDIRECT_MAX_SEND_SGE,
.sge = request->sge,
.device = info->id->device,
.local_dma_lkey = info->pd->local_dma_lkey,
.direction = DMA_TO_DEVICE,
};
rc = smb_extract_iter_to_rdma(iter, *_remaining_data_length,
&extract);
if (rc < 0)
goto err_dma;
data_length = rc;
request->num_sge = extract.nr_sge;
*_remaining_data_length -= data_length;
} else {
data_length = 0;
request->num_sge = 1;
}
/* Fill in the packet header */
packet = smbd_request_payload(request);
packet->credits_requested = cpu_to_le16(info->send_credit_target);
new_credits = manage_credits_prior_sending(info);
atomic_add(new_credits, &info->receive_credits);
packet->credits_granted = cpu_to_le16(new_credits);
info->send_immediate = false;
packet->flags = 0;
if (manage_keep_alive_before_sending(info))
packet->flags |= cpu_to_le16(SMB_DIRECT_RESPONSE_REQUESTED);
packet->reserved = 0;
if (!data_length)
packet->data_offset = 0;
else
packet->data_offset = cpu_to_le32(24);
packet->data_length = cpu_to_le32(data_length);
packet->remaining_data_length = cpu_to_le32(*_remaining_data_length);
packet->padding = 0;
log_outgoing(INFO, "credits_requested=%d credits_granted=%d data_offset=%d data_length=%d remaining_data_length=%d\n",
le16_to_cpu(packet->credits_requested),
le16_to_cpu(packet->credits_granted),
le32_to_cpu(packet->data_offset),
le32_to_cpu(packet->data_length),
le32_to_cpu(packet->remaining_data_length));
/* Map the packet to DMA */
header_length = sizeof(struct smbd_data_transfer);
/* If this is a packet without payload, don't send padding */
if (!data_length)
header_length = offsetof(struct smbd_data_transfer, padding);
request->sge[0].addr = ib_dma_map_single(info->id->device,
(void *)packet,
header_length,
DMA_TO_DEVICE);
if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
rc = -EIO;
request->sge[0].addr = 0;
goto err_dma;
}
request->sge[0].length = header_length;
request->sge[0].lkey = info->pd->local_dma_lkey;
rc = smbd_post_send(info, request);
if (!rc)
return 0;
err_dma:
for (i = 0; i < request->num_sge; i++)
if (request->sge[i].addr)
ib_dma_unmap_single(info->id->device,
request->sge[i].addr,
request->sge[i].length,
DMA_TO_DEVICE);
mempool_free(request, info->request_mempool);
/* roll back receive credits and credits to be offered */
spin_lock(&info->lock_new_credits_offered);
info->new_credits_offered += new_credits;
spin_unlock(&info->lock_new_credits_offered);
atomic_sub(new_credits, &info->receive_credits);
err_alloc:
if (atomic_dec_and_test(&info->send_pending))
wake_up(&info->wait_send_pending);
err_wait_send_queue:
/* roll back send credits and pending */
atomic_inc(&info->send_credits);
err_wait_credit:
return rc;
}
/*
* Send an empty message
* Empty message is used to extend credits to peer to for keep live
* while there is no upper layer payload to send at the time
*/
static int smbd_post_send_empty(struct smbd_connection *info)
{
int remaining_data_length = 0;
info->count_send_empty++;
return smbd_post_send_iter(info, NULL, &remaining_data_length);
}
/*
* Post a receive request to the transport
* The remote peer can only send data when a receive request is posted
* The interaction is controlled by send/receive credit system
*/
static int smbd_post_recv(
struct smbd_connection *info, struct smbd_response *response)
{
struct ib_recv_wr recv_wr;
int rc = -EIO;
response->sge.addr = ib_dma_map_single(
info->id->device, response->packet,
info->max_receive_size, DMA_FROM_DEVICE);
if (ib_dma_mapping_error(info->id->device, response->sge.addr))
return rc;
response->sge.length = info->max_receive_size;
response->sge.lkey = info->pd->local_dma_lkey;
response->cqe.done = recv_done;
recv_wr.wr_cqe = &response->cqe;
recv_wr.next = NULL;
recv_wr.sg_list = &response->sge;
recv_wr.num_sge = 1;
rc = ib_post_recv(info->id->qp, &recv_wr, NULL);
if (rc) {
ib_dma_unmap_single(info->id->device, response->sge.addr,
response->sge.length, DMA_FROM_DEVICE);
smbd_disconnect_rdma_connection(info);
log_rdma_recv(ERR, "ib_post_recv failed rc=%d\n", rc);
}
return rc;
}
/* Perform SMBD negotiate according to [MS-SMBD] 3.1.5.2 */
static int smbd_negotiate(struct smbd_connection *info)
{
int rc;
struct smbd_response *response = get_receive_buffer(info);
response->type = SMBD_NEGOTIATE_RESP;
rc = smbd_post_recv(info, response);
log_rdma_event(INFO, "smbd_post_recv rc=%d iov.addr=0x%llx iov.length=%u iov.lkey=0x%x\n",
rc, response->sge.addr,
response->sge.length, response->sge.lkey);
if (rc)
return rc;
init_completion(&info->negotiate_completion);
info->negotiate_done = false;
rc = smbd_post_send_negotiate_req(info);
if (rc)
return rc;
rc = wait_for_completion_interruptible_timeout(
&info->negotiate_completion, SMBD_NEGOTIATE_TIMEOUT * HZ);
log_rdma_event(INFO, "wait_for_completion_timeout rc=%d\n", rc);
if (info->negotiate_done)
return 0;
if (rc == 0)
rc = -ETIMEDOUT;
else if (rc == -ERESTARTSYS)
rc = -EINTR;
else
rc = -ENOTCONN;
return rc;
}
static void put_empty_packet(
struct smbd_connection *info, struct smbd_response *response)
{
spin_lock(&info->empty_packet_queue_lock);
list_add_tail(&response->list, &info->empty_packet_queue);
info->count_empty_packet_queue++;
spin_unlock(&info->empty_packet_queue_lock);
queue_work(info->workqueue, &info->post_send_credits_work);
}
/*
* Implement Connection.FragmentReassemblyBuffer defined in [MS-SMBD] 3.1.1.1
* This is a queue for reassembling upper layer payload and present to upper
* layer. All the inncoming payload go to the reassembly queue, regardless of
* if reassembly is required. The uuper layer code reads from the queue for all
* incoming payloads.
* Put a received packet to the reassembly queue
* response: the packet received
* data_length: the size of payload in this packet
*/
static void enqueue_reassembly(
struct smbd_connection *info,
struct smbd_response *response,
int data_length)
{
spin_lock(&info->reassembly_queue_lock);
list_add_tail(&response->list, &info->reassembly_queue);
info->reassembly_queue_length++;
/*
* Make sure reassembly_data_length is updated after list and
* reassembly_queue_length are updated. On the dequeue side
* reassembly_data_length is checked without a lock to determine
* if reassembly_queue_length and list is up to date
*/
virt_wmb();
info->reassembly_data_length += data_length;
spin_unlock(&info->reassembly_queue_lock);
info->count_reassembly_queue++;
info->count_enqueue_reassembly_queue++;
}
/*
* Get the first entry at the front of reassembly queue
* Caller is responsible for locking
* return value: the first entry if any, NULL if queue is empty
*/
static struct smbd_response *_get_first_reassembly(struct smbd_connection *info)
{
struct smbd_response *ret = NULL;
if (!list_empty(&info->reassembly_queue)) {
ret = list_first_entry(
&info->reassembly_queue,
struct smbd_response, list);
}
return ret;
}
static struct smbd_response *get_empty_queue_buffer(
struct smbd_connection *info)
{
struct smbd_response *ret = NULL;
unsigned long flags;
spin_lock_irqsave(&info->empty_packet_queue_lock, flags);
if (!list_empty(&info->empty_packet_queue)) {
ret = list_first_entry(
&info->empty_packet_queue,
struct smbd_response, list);
list_del(&ret->list);
info->count_empty_packet_queue--;
}
spin_unlock_irqrestore(&info->empty_packet_queue_lock, flags);
return ret;
}
/*
* Get a receive buffer
* For each remote send, we need to post a receive. The receive buffers are
* pre-allocated in advance.
* return value: the receive buffer, NULL if none is available
*/
static struct smbd_response *get_receive_buffer(struct smbd_connection *info)
{
struct smbd_response *ret = NULL;
unsigned long flags;
spin_lock_irqsave(&info->receive_queue_lock, flags);
if (!list_empty(&info->receive_queue)) {
ret = list_first_entry(
&info->receive_queue,
struct smbd_response, list);
list_del(&ret->list);
info->count_receive_queue--;
info->count_get_receive_buffer++;
}
spin_unlock_irqrestore(&info->receive_queue_lock, flags);
return ret;
}
/*
* Return a receive buffer
* Upon returning of a receive buffer, we can post new receive and extend
* more receive credits to remote peer. This is done immediately after a
* receive buffer is returned.
*/
static void put_receive_buffer(
struct smbd_connection *info, struct smbd_response *response)
{
unsigned long flags;
ib_dma_unmap_single(info->id->device, response->sge.addr,
response->sge.length, DMA_FROM_DEVICE);
spin_lock_irqsave(&info->receive_queue_lock, flags);
list_add_tail(&response->list, &info->receive_queue);
info->count_receive_queue++;
info->count_put_receive_buffer++;
spin_unlock_irqrestore(&info->receive_queue_lock, flags);
queue_work(info->workqueue, &info->post_send_credits_work);
}
/* Preallocate all receive buffer on transport establishment */
static int allocate_receive_buffers(struct smbd_connection *info, int num_buf)
{
int i;
struct smbd_response *response;
INIT_LIST_HEAD(&info->reassembly_queue);
spin_lock_init(&info->reassembly_queue_lock);
info->reassembly_data_length = 0;
info->reassembly_queue_length = 0;
INIT_LIST_HEAD(&info->receive_queue);
spin_lock_init(&info->receive_queue_lock);
info->count_receive_queue = 0;
INIT_LIST_HEAD(&info->empty_packet_queue);
spin_lock_init(&info->empty_packet_queue_lock);
info->count_empty_packet_queue = 0;
init_waitqueue_head(&info->wait_receive_queues);
for (i = 0; i < num_buf; i++) {
response = mempool_alloc(info->response_mempool, GFP_KERNEL);
if (!response)
goto allocate_failed;
response->info = info;
list_add_tail(&response->list, &info->receive_queue);
info->count_receive_queue++;
}
return 0;
allocate_failed:
while (!list_empty(&info->receive_queue)) {
response = list_first_entry(
&info->receive_queue,
struct smbd_response, list);
list_del(&response->list);
info->count_receive_queue--;
mempool_free(response, info->response_mempool);
}
return -ENOMEM;
}
static void destroy_receive_buffers(struct smbd_connection *info)
{
struct smbd_response *response;
while ((response = get_receive_buffer(info)))
mempool_free(response, info->response_mempool);
while ((response = get_empty_queue_buffer(info)))
mempool_free(response, info->response_mempool);
}
/* Implement idle connection timer [MS-SMBD] 3.1.6.2 */
static void idle_connection_timer(struct work_struct *work)
{
struct smbd_connection *info = container_of(
work, struct smbd_connection,
idle_timer_work.work);
if (info->keep_alive_requested != KEEP_ALIVE_NONE) {
log_keep_alive(ERR,
"error status info->keep_alive_requested=%d\n",
info->keep_alive_requested);
smbd_disconnect_rdma_connection(info);
return;
}
log_keep_alive(INFO, "about to send an empty idle message\n");
smbd_post_send_empty(info);
/* Setup the next idle timeout work */
queue_delayed_work(info->workqueue, &info->idle_timer_work,
info->keep_alive_interval*HZ);
}
/*
* Destroy the transport and related RDMA and memory resources
* Need to go through all the pending counters and make sure on one is using
* the transport while it is destroyed
*/
void smbd_destroy(struct TCP_Server_Info *server)
{
struct smbd_connection *info = server->smbd_conn;
struct smbd_response *response;
unsigned long flags;
if (!info) {
log_rdma_event(INFO, "rdma session already destroyed\n");
return;
}
log_rdma_event(INFO, "destroying rdma session\n");
if (info->transport_status != SMBD_DISCONNECTED) {
rdma_disconnect(server->smbd_conn->id);
log_rdma_event(INFO, "wait for transport being disconnected\n");
wait_event_interruptible(
info->disconn_wait,
info->transport_status == SMBD_DISCONNECTED);
}
log_rdma_event(INFO, "destroying qp\n");
ib_drain_qp(info->id->qp);
rdma_destroy_qp(info->id);
log_rdma_event(INFO, "cancelling idle timer\n");
cancel_delayed_work_sync(&info->idle_timer_work);
log_rdma_event(INFO, "wait for all send posted to IB to finish\n");
wait_event(info->wait_send_pending,
atomic_read(&info->send_pending) == 0);
/* It's not possible for upper layer to get to reassembly */
log_rdma_event(INFO, "drain the reassembly queue\n");
do {
spin_lock_irqsave(&info->reassembly_queue_lock, flags);
response = _get_first_reassembly(info);
if (response) {
list_del(&response->list);
spin_unlock_irqrestore(
&info->reassembly_queue_lock, flags);
put_receive_buffer(info, response);
} else
spin_unlock_irqrestore(
&info->reassembly_queue_lock, flags);
} while (response);
info->reassembly_data_length = 0;
log_rdma_event(INFO, "free receive buffers\n");
wait_event(info->wait_receive_queues,
info->count_receive_queue + info->count_empty_packet_queue
== info->receive_credit_max);
destroy_receive_buffers(info);
/*
* For performance reasons, memory registration and deregistration
* are not locked by srv_mutex. It is possible some processes are
* blocked on transport srv_mutex while holding memory registration.
* Release the transport srv_mutex to allow them to hit the failure
* path when sending data, and then release memory registartions.
*/
log_rdma_event(INFO, "freeing mr list\n");
wake_up_interruptible_all(&info->wait_mr);
while (atomic_read(&info->mr_used_count)) {
cifs_server_unlock(server);
msleep(1000);
cifs_server_lock(server);
}
destroy_mr_list(info);
ib_free_cq(info->send_cq);
ib_free_cq(info->recv_cq);
ib_dealloc_pd(info->pd);
rdma_destroy_id(info->id);
/* free mempools */
mempool_destroy(info->request_mempool);
kmem_cache_destroy(info->request_cache);
mempool_destroy(info->response_mempool);
kmem_cache_destroy(info->response_cache);
info->transport_status = SMBD_DESTROYED;
destroy_workqueue(info->workqueue);
log_rdma_event(INFO, "rdma session destroyed\n");
kfree(info);
server->smbd_conn = NULL;
}
/*
* Reconnect this SMBD connection, called from upper layer
* return value: 0 on success, or actual error code
*/
int smbd_reconnect(struct TCP_Server_Info *server)
{
log_rdma_event(INFO, "reconnecting rdma session\n");
if (!server->smbd_conn) {
log_rdma_event(INFO, "rdma session already destroyed\n");
goto create_conn;
}
/*
* This is possible if transport is disconnected and we haven't received
* notification from RDMA, but upper layer has detected timeout
*/
if (server->smbd_conn->transport_status == SMBD_CONNECTED) {
log_rdma_event(INFO, "disconnecting transport\n");
smbd_destroy(server);
}
create_conn:
log_rdma_event(INFO, "creating rdma session\n");
server->smbd_conn = smbd_get_connection(
server, (struct sockaddr *) &server->dstaddr);
if (server->smbd_conn)
cifs_dbg(VFS, "RDMA transport re-established\n");
return server->smbd_conn ? 0 : -ENOENT;
}
static void destroy_caches_and_workqueue(struct smbd_connection *info)
{
destroy_receive_buffers(info);
destroy_workqueue(info->workqueue);
mempool_destroy(info->response_mempool);
kmem_cache_destroy(info->response_cache);
mempool_destroy(info->request_mempool);
kmem_cache_destroy(info->request_cache);
}
#define MAX_NAME_LEN 80
static int allocate_caches_and_workqueue(struct smbd_connection *info)
{
char name[MAX_NAME_LEN];
int rc;
scnprintf(name, MAX_NAME_LEN, "smbd_request_%p", info);
info->request_cache =
kmem_cache_create(
name,
sizeof(struct smbd_request) +
sizeof(struct smbd_data_transfer),
0, SLAB_HWCACHE_ALIGN, NULL);
if (!info->request_cache)
return -ENOMEM;
info->request_mempool =
mempool_create(info->send_credit_target, mempool_alloc_slab,
mempool_free_slab, info->request_cache);
if (!info->request_mempool)
goto out1;
scnprintf(name, MAX_NAME_LEN, "smbd_response_%p", info);
info->response_cache =
kmem_cache_create(
name,
sizeof(struct smbd_response) +
info->max_receive_size,
0, SLAB_HWCACHE_ALIGN, NULL);
if (!info->response_cache)
goto out2;
info->response_mempool =
mempool_create(info->receive_credit_max, mempool_alloc_slab,
mempool_free_slab, info->response_cache);
if (!info->response_mempool)
goto out3;
scnprintf(name, MAX_NAME_LEN, "smbd_%p", info);
info->workqueue = create_workqueue(name);
if (!info->workqueue)
goto out4;
rc = allocate_receive_buffers(info, info->receive_credit_max);
if (rc) {
log_rdma_event(ERR, "failed to allocate receive buffers\n");
goto out5;
}
return 0;
out5:
destroy_workqueue(info->workqueue);
out4:
mempool_destroy(info->response_mempool);
out3:
kmem_cache_destroy(info->response_cache);
out2:
mempool_destroy(info->request_mempool);
out1:
kmem_cache_destroy(info->request_cache);
return -ENOMEM;
}
/* Create a SMBD connection, called by upper layer */
static struct smbd_connection *_smbd_get_connection(
struct TCP_Server_Info *server, struct sockaddr *dstaddr, int port)
{
int rc;
struct smbd_connection *info;
struct rdma_conn_param conn_param;
struct ib_qp_init_attr qp_attr;
struct sockaddr_in *addr_in = (struct sockaddr_in *) dstaddr;
struct ib_port_immutable port_immutable;
u32 ird_ord_hdr[2];
info = kzalloc(sizeof(struct smbd_connection), GFP_KERNEL);
if (!info)
return NULL;
info->transport_status = SMBD_CONNECTING;
rc = smbd_ia_open(info, dstaddr, port);
if (rc) {
log_rdma_event(INFO, "smbd_ia_open rc=%d\n", rc);
goto create_id_failed;
}
if (smbd_send_credit_target > info->id->device->attrs.max_cqe ||
smbd_send_credit_target > info->id->device->attrs.max_qp_wr) {
log_rdma_event(ERR, "consider lowering send_credit_target = %d. Possible CQE overrun, device reporting max_cqe %d max_qp_wr %d\n",
smbd_send_credit_target,
info->id->device->attrs.max_cqe,
info->id->device->attrs.max_qp_wr);
goto config_failed;
}
if (smbd_receive_credit_max > info->id->device->attrs.max_cqe ||
smbd_receive_credit_max > info->id->device->attrs.max_qp_wr) {
log_rdma_event(ERR, "consider lowering receive_credit_max = %d. Possible CQE overrun, device reporting max_cqe %d max_qp_wr %d\n",
smbd_receive_credit_max,
info->id->device->attrs.max_cqe,
info->id->device->attrs.max_qp_wr);
goto config_failed;
}
info->receive_credit_max = smbd_receive_credit_max;
info->send_credit_target = smbd_send_credit_target;
info->max_send_size = smbd_max_send_size;
info->max_fragmented_recv_size = smbd_max_fragmented_recv_size;
info->max_receive_size = smbd_max_receive_size;
info->keep_alive_interval = smbd_keep_alive_interval;
if (info->id->device->attrs.max_send_sge < SMBDIRECT_MAX_SEND_SGE ||
info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_RECV_SGE) {
log_rdma_event(ERR,
"device %.*s max_send_sge/max_recv_sge = %d/%d too small\n",
IB_DEVICE_NAME_MAX,
info->id->device->name,
info->id->device->attrs.max_send_sge,
info->id->device->attrs.max_recv_sge);
goto config_failed;
}
info->send_cq = NULL;
info->recv_cq = NULL;
info->send_cq =
ib_alloc_cq_any(info->id->device, info,
info->send_credit_target, IB_POLL_SOFTIRQ);
if (IS_ERR(info->send_cq)) {
info->send_cq = NULL;
goto alloc_cq_failed;
}
info->recv_cq =
ib_alloc_cq_any(info->id->device, info,
info->receive_credit_max, IB_POLL_SOFTIRQ);
if (IS_ERR(info->recv_cq)) {
info->recv_cq = NULL;
goto alloc_cq_failed;
}
memset(&qp_attr, 0, sizeof(qp_attr));
qp_attr.event_handler = smbd_qp_async_error_upcall;
qp_attr.qp_context = info;
qp_attr.cap.max_send_wr = info->send_credit_target;
qp_attr.cap.max_recv_wr = info->receive_credit_max;
qp_attr.cap.max_send_sge = SMBDIRECT_MAX_SEND_SGE;
qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_RECV_SGE;
qp_attr.cap.max_inline_data = 0;
qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
qp_attr.qp_type = IB_QPT_RC;
qp_attr.send_cq = info->send_cq;
qp_attr.recv_cq = info->recv_cq;
qp_attr.port_num = ~0;
rc = rdma_create_qp(info->id, info->pd, &qp_attr);
if (rc) {
log_rdma_event(ERR, "rdma_create_qp failed %i\n", rc);
goto create_qp_failed;
}
memset(&conn_param, 0, sizeof(conn_param));
conn_param.initiator_depth = 0;
conn_param.responder_resources =
info->id->device->attrs.max_qp_rd_atom
< SMBD_CM_RESPONDER_RESOURCES ?
info->id->device->attrs.max_qp_rd_atom :
SMBD_CM_RESPONDER_RESOURCES;
info->responder_resources = conn_param.responder_resources;
log_rdma_mr(INFO, "responder_resources=%d\n",
info->responder_resources);
/* Need to send IRD/ORD in private data for iWARP */
info->id->device->ops.get_port_immutable(
info->id->device, info->id->port_num, &port_immutable);
if (port_immutable.core_cap_flags & RDMA_CORE_PORT_IWARP) {
ird_ord_hdr[0] = info->responder_resources;
ird_ord_hdr[1] = 1;
conn_param.private_data = ird_ord_hdr;
conn_param.private_data_len = sizeof(ird_ord_hdr);
} else {
conn_param.private_data = NULL;
conn_param.private_data_len = 0;
}
conn_param.retry_count = SMBD_CM_RETRY;
conn_param.rnr_retry_count = SMBD_CM_RNR_RETRY;
conn_param.flow_control = 0;
log_rdma_event(INFO, "connecting to IP %pI4 port %d\n",
&addr_in->sin_addr, port);
init_waitqueue_head(&info->conn_wait);
init_waitqueue_head(&info->disconn_wait);
init_waitqueue_head(&info->wait_reassembly_queue);
rc = rdma_connect(info->id, &conn_param);
if (rc) {
log_rdma_event(ERR, "rdma_connect() failed with %i\n", rc);
goto rdma_connect_failed;
}
wait_event_interruptible(
info->conn_wait, info->transport_status != SMBD_CONNECTING);
if (info->transport_status != SMBD_CONNECTED) {
log_rdma_event(ERR, "rdma_connect failed port=%d\n", port);
goto rdma_connect_failed;
}
log_rdma_event(INFO, "rdma_connect connected\n");
rc = allocate_caches_and_workqueue(info);
if (rc) {
log_rdma_event(ERR, "cache allocation failed\n");
goto allocate_cache_failed;
}
init_waitqueue_head(&info->wait_send_queue);
INIT_DELAYED_WORK(&info->idle_timer_work, idle_connection_timer);
queue_delayed_work(info->workqueue, &info->idle_timer_work,
info->keep_alive_interval*HZ);
init_waitqueue_head(&info->wait_send_pending);
atomic_set(&info->send_pending, 0);
init_waitqueue_head(&info->wait_post_send);
INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work);
INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits);
info->new_credits_offered = 0;
spin_lock_init(&info->lock_new_credits_offered);
rc = smbd_negotiate(info);
if (rc) {
log_rdma_event(ERR, "smbd_negotiate rc=%d\n", rc);
goto negotiation_failed;
}
rc = allocate_mr_list(info);
if (rc) {
log_rdma_mr(ERR, "memory registration allocation failed\n");
goto allocate_mr_failed;
}
return info;
allocate_mr_failed:
/* At this point, need to a full transport shutdown */
server->smbd_conn = info;
smbd_destroy(server);
return NULL;
negotiation_failed:
cancel_delayed_work_sync(&info->idle_timer_work);
destroy_caches_and_workqueue(info);
info->transport_status = SMBD_NEGOTIATE_FAILED;
init_waitqueue_head(&info->conn_wait);
rdma_disconnect(info->id);
wait_event(info->conn_wait,
info->transport_status == SMBD_DISCONNECTED);
allocate_cache_failed:
rdma_connect_failed:
rdma_destroy_qp(info->id);
create_qp_failed:
alloc_cq_failed:
if (info->send_cq)
ib_free_cq(info->send_cq);
if (info->recv_cq)
ib_free_cq(info->recv_cq);
config_failed:
ib_dealloc_pd(info->pd);
rdma_destroy_id(info->id);
create_id_failed:
kfree(info);
return NULL;
}
struct smbd_connection *smbd_get_connection(
struct TCP_Server_Info *server, struct sockaddr *dstaddr)
{
struct smbd_connection *ret;
int port = SMBD_PORT;
try_again:
ret = _smbd_get_connection(server, dstaddr, port);
/* Try SMB_PORT if SMBD_PORT doesn't work */
if (!ret && port == SMBD_PORT) {
port = SMB_PORT;
goto try_again;
}
return ret;
}
/*
* Receive data from receive reassembly queue
* All the incoming data packets are placed in reassembly queue
* buf: the buffer to read data into
* size: the length of data to read
* return value: actual data read
* Note: this implementation copies the data from reassebmly queue to receive
* buffers used by upper layer. This is not the optimal code path. A better way
* to do it is to not have upper layer allocate its receive buffers but rather
* borrow the buffer from reassembly queue, and return it after data is
* consumed. But this will require more changes to upper layer code, and also
* need to consider packet boundaries while they still being reassembled.
*/
static int smbd_recv_buf(struct smbd_connection *info, char *buf,
unsigned int size)
{
struct smbd_response *response;
struct smbd_data_transfer *data_transfer;
int to_copy, to_read, data_read, offset;
u32 data_length, remaining_data_length, data_offset;
int rc;
again:
/*
* No need to hold the reassembly queue lock all the time as we are
* the only one reading from the front of the queue. The transport
* may add more entries to the back of the queue at the same time
*/
log_read(INFO, "size=%d info->reassembly_data_length=%d\n", size,
info->reassembly_data_length);
if (info->reassembly_data_length >= size) {
int queue_length;
int queue_removed = 0;
/*
* Need to make sure reassembly_data_length is read before
* reading reassembly_queue_length and calling
* _get_first_reassembly. This call is lock free
* as we never read at the end of the queue which are being
* updated in SOFTIRQ as more data is received
*/
virt_rmb();
queue_length = info->reassembly_queue_length;
data_read = 0;
to_read = size;
offset = info->first_entry_offset;
while (data_read < size) {
response = _get_first_reassembly(info);
data_transfer = smbd_response_payload(response);
data_length = le32_to_cpu(data_transfer->data_length);
remaining_data_length =
le32_to_cpu(
data_transfer->remaining_data_length);
data_offset = le32_to_cpu(data_transfer->data_offset);
/*
* The upper layer expects RFC1002 length at the
* beginning of the payload. Return it to indicate
* the total length of the packet. This minimize the
* change to upper layer packet processing logic. This
* will be eventually remove when an intermediate
* transport layer is added
*/
if (response->first_segment && size == 4) {
unsigned int rfc1002_len =
data_length + remaining_data_length;
*((__be32 *)buf) = cpu_to_be32(rfc1002_len);
data_read = 4;
response->first_segment = false;
log_read(INFO, "returning rfc1002 length %d\n",
rfc1002_len);
goto read_rfc1002_done;
}
to_copy = min_t(int, data_length - offset, to_read);
memcpy(
buf + data_read,
(char *)data_transfer + data_offset + offset,
to_copy);
/* move on to the next buffer? */
if (to_copy == data_length - offset) {
queue_length--;
/*
* No need to lock if we are not at the
* end of the queue
*/
if (queue_length)
list_del(&response->list);
else {
spin_lock_irq(
&info->reassembly_queue_lock);
list_del(&response->list);
spin_unlock_irq(
&info->reassembly_queue_lock);
}
queue_removed++;
info->count_reassembly_queue--;
info->count_dequeue_reassembly_queue++;
put_receive_buffer(info, response);
offset = 0;
log_read(INFO, "put_receive_buffer offset=0\n");
} else
offset += to_copy;
to_read -= to_copy;
data_read += to_copy;
log_read(INFO, "_get_first_reassembly memcpy %d bytes data_transfer_length-offset=%d after that to_read=%d data_read=%d offset=%d\n",
to_copy, data_length - offset,
to_read, data_read, offset);
}
spin_lock_irq(&info->reassembly_queue_lock);
info->reassembly_data_length -= data_read;
info->reassembly_queue_length -= queue_removed;
spin_unlock_irq(&info->reassembly_queue_lock);
info->first_entry_offset = offset;
log_read(INFO, "returning to thread data_read=%d reassembly_data_length=%d first_entry_offset=%d\n",
data_read, info->reassembly_data_length,
info->first_entry_offset);
read_rfc1002_done:
return data_read;
}
log_read(INFO, "wait_event on more data\n");
rc = wait_event_interruptible(
info->wait_reassembly_queue,
info->reassembly_data_length >= size ||
info->transport_status != SMBD_CONNECTED);
/* Don't return any data if interrupted */
if (rc)
return rc;
if (info->transport_status != SMBD_CONNECTED) {
log_read(ERR, "disconnected\n");
return -ECONNABORTED;
}
goto again;
}
/*
* Receive a page from receive reassembly queue
* page: the page to read data into
* to_read: the length of data to read
* return value: actual data read
*/
static int smbd_recv_page(struct smbd_connection *info,
struct page *page, unsigned int page_offset,
unsigned int to_read)
{
int ret;
char *to_address;
void *page_address;
/* make sure we have the page ready for read */
ret = wait_event_interruptible(
info->wait_reassembly_queue,
info->reassembly_data_length >= to_read ||
info->transport_status != SMBD_CONNECTED);
if (ret)
return ret;
/* now we can read from reassembly queue and not sleep */
page_address = kmap_atomic(page);
to_address = (char *) page_address + page_offset;
log_read(INFO, "reading from page=%p address=%p to_read=%d\n",
page, to_address, to_read);
ret = smbd_recv_buf(info, to_address, to_read);
kunmap_atomic(page_address);
return ret;
}
/*
* Receive data from transport
* msg: a msghdr point to the buffer, can be ITER_KVEC or ITER_BVEC
* return: total bytes read, or 0. SMB Direct will not do partial read.
*/
int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
{
char *buf;
struct page *page;
unsigned int to_read, page_offset;
int rc;
if (iov_iter_rw(&msg->msg_iter) == WRITE) {
/* It's a bug in upper layer to get there */
cifs_dbg(VFS, "Invalid msg iter dir %u\n",
iov_iter_rw(&msg->msg_iter));
rc = -EINVAL;
goto out;
}
switch (iov_iter_type(&msg->msg_iter)) {
case ITER_KVEC:
buf = msg->msg_iter.kvec->iov_base;
to_read = msg->msg_iter.kvec->iov_len;
rc = smbd_recv_buf(info, buf, to_read);
break;
case ITER_BVEC:
page = msg->msg_iter.bvec->bv_page;
page_offset = msg->msg_iter.bvec->bv_offset;
to_read = msg->msg_iter.bvec->bv_len;
rc = smbd_recv_page(info, page, page_offset, to_read);
break;
default:
/* It's a bug in upper layer to get there */
cifs_dbg(VFS, "Invalid msg type %d\n",
iov_iter_type(&msg->msg_iter));
rc = -EINVAL;
}
out:
/* SMBDirect will read it all or nothing */
if (rc > 0)
msg->msg_iter.count = 0;
return rc;
}
/*
* Send data to transport
* Each rqst is transported as a SMBDirect payload
* rqst: the data to write
* return value: 0 if successfully write, otherwise error code
*/
int smbd_send(struct TCP_Server_Info *server,
int num_rqst, struct smb_rqst *rqst_array)
{
struct smbd_connection *info = server->smbd_conn;
struct smb_rqst *rqst;
struct iov_iter iter;
unsigned int remaining_data_length, klen;
int rc, i, rqst_idx;
if (info->transport_status != SMBD_CONNECTED)
return -EAGAIN;
/*
* Add in the page array if there is one. The caller needs to set
* rq_tailsz to PAGE_SIZE when the buffer has multiple pages and
* ends at page boundary
*/
remaining_data_length = 0;
for (i = 0; i < num_rqst; i++)
remaining_data_length += smb_rqst_len(server, &rqst_array[i]);
if (unlikely(remaining_data_length > info->max_fragmented_send_size)) {
/* assertion: payload never exceeds negotiated maximum */
log_write(ERR, "payload size %d > max size %d\n",
remaining_data_length, info->max_fragmented_send_size);
return -EINVAL;
}
log_write(INFO, "num_rqst=%d total length=%u\n",
num_rqst, remaining_data_length);
rqst_idx = 0;
do {
rqst = &rqst_array[rqst_idx];
cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n",
rqst_idx, smb_rqst_len(server, rqst));
for (i = 0; i < rqst->rq_nvec; i++)
dump_smb(rqst->rq_iov[i].iov_base, rqst->rq_iov[i].iov_len);
log_write(INFO, "RDMA-WR[%u] nvec=%d len=%u iter=%zu rqlen=%lu\n",
rqst_idx, rqst->rq_nvec, remaining_data_length,
iov_iter_count(&rqst->rq_iter), smb_rqst_len(server, rqst));
/* Send the metadata pages. */
klen = 0;
for (i = 0; i < rqst->rq_nvec; i++)
klen += rqst->rq_iov[i].iov_len;
iov_iter_kvec(&iter, ITER_SOURCE, rqst->rq_iov, rqst->rq_nvec, klen);
rc = smbd_post_send_iter(info, &iter, &remaining_data_length);
if (rc < 0)
break;
if (iov_iter_count(&rqst->rq_iter) > 0) {
/* And then the data pages if there are any */
rc = smbd_post_send_iter(info, &rqst->rq_iter,
&remaining_data_length);
if (rc < 0)
break;
}
} while (++rqst_idx < num_rqst);
/*
* As an optimization, we don't wait for individual I/O to finish
* before sending the next one.
* Send them all and wait for pending send count to get to 0
* that means all the I/Os have been out and we are good to return
*/
wait_event(info->wait_send_pending,
atomic_read(&info->send_pending) == 0);
return rc;
}
static void register_mr_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct smbd_mr *mr;
struct ib_cqe *cqe;
if (wc->status) {
log_rdma_mr(ERR, "status=%d\n", wc->status);
cqe = wc->wr_cqe;
mr = container_of(cqe, struct smbd_mr, cqe);
smbd_disconnect_rdma_connection(mr->conn);
}
}
/*
* The work queue function that recovers MRs
* We need to call ib_dereg_mr() and ib_alloc_mr() before this MR can be used
* again. Both calls are slow, so finish them in a workqueue. This will not
* block I/O path.
* There is one workqueue that recovers MRs, there is no need to lock as the
* I/O requests calling smbd_register_mr will never update the links in the
* mr_list.
*/
static void smbd_mr_recovery_work(struct work_struct *work)
{
struct smbd_connection *info =
container_of(work, struct smbd_connection, mr_recovery_work);
struct smbd_mr *smbdirect_mr;
int rc;
list_for_each_entry(smbdirect_mr, &info->mr_list, list) {
if (smbdirect_mr->state == MR_ERROR) {
/* recover this MR entry */
rc = ib_dereg_mr(smbdirect_mr->mr);
if (rc) {
log_rdma_mr(ERR,
"ib_dereg_mr failed rc=%x\n",
rc);
smbd_disconnect_rdma_connection(info);
continue;
}
smbdirect_mr->mr = ib_alloc_mr(
info->pd, info->mr_type,
info->max_frmr_depth);
if (IS_ERR(smbdirect_mr->mr)) {
log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x max_frmr_depth=%x\n",
info->mr_type,
info->max_frmr_depth);
smbd_disconnect_rdma_connection(info);
continue;
}
} else
/* This MR is being used, don't recover it */
continue;
smbdirect_mr->state = MR_READY;
/* smbdirect_mr->state is updated by this function
* and is read and updated by I/O issuing CPUs trying
* to get a MR, the call to atomic_inc_return
* implicates a memory barrier and guarantees this
* value is updated before waking up any calls to
* get_mr() from the I/O issuing CPUs
*/
if (atomic_inc_return(&info->mr_ready_count) == 1)
wake_up_interruptible(&info->wait_mr);
}
}
static void destroy_mr_list(struct smbd_connection *info)
{
struct smbd_mr *mr, *tmp;
cancel_work_sync(&info->mr_recovery_work);
list_for_each_entry_safe(mr, tmp, &info->mr_list, list) {
if (mr->state == MR_INVALIDATED)
ib_dma_unmap_sg(info->id->device, mr->sgt.sgl,
mr->sgt.nents, mr->dir);
ib_dereg_mr(mr->mr);
kfree(mr->sgt.sgl);
kfree(mr);
}
}
/*
* Allocate MRs used for RDMA read/write
* The number of MRs will not exceed hardware capability in responder_resources
* All MRs are kept in mr_list. The MR can be recovered after it's used
* Recovery is done in smbd_mr_recovery_work. The content of list entry changes
* as MRs are used and recovered for I/O, but the list links will not change
*/
static int allocate_mr_list(struct smbd_connection *info)
{
int i;
struct smbd_mr *smbdirect_mr, *tmp;
INIT_LIST_HEAD(&info->mr_list);
init_waitqueue_head(&info->wait_mr);
spin_lock_init(&info->mr_list_lock);
atomic_set(&info->mr_ready_count, 0);
atomic_set(&info->mr_used_count, 0);
init_waitqueue_head(&info->wait_for_mr_cleanup);
INIT_WORK(&info->mr_recovery_work, smbd_mr_recovery_work);
/* Allocate more MRs (2x) than hardware responder_resources */
for (i = 0; i < info->responder_resources * 2; i++) {
smbdirect_mr = kzalloc(sizeof(*smbdirect_mr), GFP_KERNEL);
if (!smbdirect_mr)
goto out;
smbdirect_mr->mr = ib_alloc_mr(info->pd, info->mr_type,
info->max_frmr_depth);
if (IS_ERR(smbdirect_mr->mr)) {
log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x max_frmr_depth=%x\n",
info->mr_type, info->max_frmr_depth);
goto out;
}
smbdirect_mr->sgt.sgl = kcalloc(info->max_frmr_depth,
sizeof(struct scatterlist),
GFP_KERNEL);
if (!smbdirect_mr->sgt.sgl) {
log_rdma_mr(ERR, "failed to allocate sgl\n");
ib_dereg_mr(smbdirect_mr->mr);
goto out;
}
smbdirect_mr->state = MR_READY;
smbdirect_mr->conn = info;
list_add_tail(&smbdirect_mr->list, &info->mr_list);
atomic_inc(&info->mr_ready_count);
}
return 0;
out:
kfree(smbdirect_mr);
list_for_each_entry_safe(smbdirect_mr, tmp, &info->mr_list, list) {
list_del(&smbdirect_mr->list);
ib_dereg_mr(smbdirect_mr->mr);
kfree(smbdirect_mr->sgt.sgl);
kfree(smbdirect_mr);
}
return -ENOMEM;
}
/*
* Get a MR from mr_list. This function waits until there is at least one
* MR available in the list. It may access the list while the
* smbd_mr_recovery_work is recovering the MR list. This doesn't need a lock
* as they never modify the same places. However, there may be several CPUs
* issueing I/O trying to get MR at the same time, mr_list_lock is used to
* protect this situation.
*/
static struct smbd_mr *get_mr(struct smbd_connection *info)
{
struct smbd_mr *ret;
int rc;
again:
rc = wait_event_interruptible(info->wait_mr,
atomic_read(&info->mr_ready_count) ||
info->transport_status != SMBD_CONNECTED);
if (rc) {
log_rdma_mr(ERR, "wait_event_interruptible rc=%x\n", rc);
return NULL;
}
if (info->transport_status != SMBD_CONNECTED) {
log_rdma_mr(ERR, "info->transport_status=%x\n",
info->transport_status);
return NULL;
}
spin_lock(&info->mr_list_lock);
list_for_each_entry(ret, &info->mr_list, list) {
if (ret->state == MR_READY) {
ret->state = MR_REGISTERED;
spin_unlock(&info->mr_list_lock);
atomic_dec(&info->mr_ready_count);
atomic_inc(&info->mr_used_count);
return ret;
}
}
spin_unlock(&info->mr_list_lock);
/*
* It is possible that we could fail to get MR because other processes may
* try to acquire a MR at the same time. If this is the case, retry it.
*/
goto again;
}
/*
* Transcribe the pages from an iterator into an MR scatterlist.
*/
static int smbd_iter_to_mr(struct smbd_connection *info,
struct iov_iter *iter,
struct sg_table *sgt,
unsigned int max_sg)
{
int ret;
memset(sgt->sgl, 0, max_sg * sizeof(struct scatterlist));
ret = netfs_extract_iter_to_sg(iter, iov_iter_count(iter), sgt, max_sg, 0);
WARN_ON(ret < 0);
if (sgt->nents > 0)
sg_mark_end(&sgt->sgl[sgt->nents - 1]);
return ret;
}
/*
* Register memory for RDMA read/write
* iter: the buffer to register memory with
* writing: true if this is a RDMA write (SMB read), false for RDMA read
* need_invalidate: true if this MR needs to be locally invalidated after I/O
* return value: the MR registered, NULL if failed.
*/
struct smbd_mr *smbd_register_mr(struct smbd_connection *info,
struct iov_iter *iter,
bool writing, bool need_invalidate)
{
struct smbd_mr *smbdirect_mr;
int rc, num_pages;
enum dma_data_direction dir;
struct ib_reg_wr *reg_wr;
num_pages = iov_iter_npages(iter, info->max_frmr_depth + 1);
if (num_pages > info->max_frmr_depth) {
log_rdma_mr(ERR, "num_pages=%d max_frmr_depth=%d\n",
num_pages, info->max_frmr_depth);
WARN_ON_ONCE(1);
return NULL;
}
smbdirect_mr = get_mr(info);
if (!smbdirect_mr) {
log_rdma_mr(ERR, "get_mr returning NULL\n");
return NULL;
}
dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
smbdirect_mr->dir = dir;
smbdirect_mr->need_invalidate = need_invalidate;
smbdirect_mr->sgt.nents = 0;
smbdirect_mr->sgt.orig_nents = 0;
log_rdma_mr(INFO, "num_pages=0x%x count=0x%zx depth=%u\n",
num_pages, iov_iter_count(iter), info->max_frmr_depth);
smbd_iter_to_mr(info, iter, &smbdirect_mr->sgt, info->max_frmr_depth);
rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgt.sgl,
smbdirect_mr->sgt.nents, dir);
if (!rc) {
log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
num_pages, dir, rc);
goto dma_map_error;
}
rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgt.sgl,
smbdirect_mr->sgt.nents, NULL, PAGE_SIZE);
if (rc != smbdirect_mr->sgt.nents) {
log_rdma_mr(ERR,
"ib_map_mr_sg failed rc = %d nents = %x\n",
rc, smbdirect_mr->sgt.nents);
goto map_mr_error;
}
ib_update_fast_reg_key(smbdirect_mr->mr,
ib_inc_rkey(smbdirect_mr->mr->rkey));
reg_wr = &smbdirect_mr->wr;
reg_wr->wr.opcode = IB_WR_REG_MR;
smbdirect_mr->cqe.done = register_mr_done;
reg_wr->wr.wr_cqe = &smbdirect_mr->cqe;
reg_wr->wr.num_sge = 0;
reg_wr->wr.send_flags = IB_SEND_SIGNALED;
reg_wr->mr = smbdirect_mr->mr;
reg_wr->key = smbdirect_mr->mr->rkey;
reg_wr->access = writing ?
IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
IB_ACCESS_REMOTE_READ;
/*
* There is no need for waiting for complemtion on ib_post_send
* on IB_WR_REG_MR. Hardware enforces a barrier and order of execution
* on the next ib_post_send when we actaully send I/O to remote peer
*/
rc = ib_post_send(info->id->qp, &reg_wr->wr, NULL);
if (!rc)
return smbdirect_mr;
log_rdma_mr(ERR, "ib_post_send failed rc=%x reg_wr->key=%x\n",
rc, reg_wr->key);
/* If all failed, attempt to recover this MR by setting it MR_ERROR*/
map_mr_error:
ib_dma_unmap_sg(info->id->device, smbdirect_mr->sgt.sgl,
smbdirect_mr->sgt.nents, smbdirect_mr->dir);
dma_map_error:
smbdirect_mr->state = MR_ERROR;
if (atomic_dec_and_test(&info->mr_used_count))
wake_up(&info->wait_for_mr_cleanup);
smbd_disconnect_rdma_connection(info);
return NULL;
}
static void local_inv_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct smbd_mr *smbdirect_mr;
struct ib_cqe *cqe;
cqe = wc->wr_cqe;
smbdirect_mr = container_of(cqe, struct smbd_mr, cqe);
smbdirect_mr->state = MR_INVALIDATED;
if (wc->status != IB_WC_SUCCESS) {
log_rdma_mr(ERR, "invalidate failed status=%x\n", wc->status);
smbdirect_mr->state = MR_ERROR;
}
complete(&smbdirect_mr->invalidate_done);
}
/*
* Deregister a MR after I/O is done
* This function may wait if remote invalidation is not used
* and we have to locally invalidate the buffer to prevent data is being
* modified by remote peer after upper layer consumes it
*/
int smbd_deregister_mr(struct smbd_mr *smbdirect_mr)
{
struct ib_send_wr *wr;
struct smbd_connection *info = smbdirect_mr->conn;
int rc = 0;
if (smbdirect_mr->need_invalidate) {
/* Need to finish local invalidation before returning */
wr = &smbdirect_mr->inv_wr;
wr->opcode = IB_WR_LOCAL_INV;
smbdirect_mr->cqe.done = local_inv_done;
wr->wr_cqe = &smbdirect_mr->cqe;
wr->num_sge = 0;
wr->ex.invalidate_rkey = smbdirect_mr->mr->rkey;
wr->send_flags = IB_SEND_SIGNALED;
init_completion(&smbdirect_mr->invalidate_done);
rc = ib_post_send(info->id->qp, wr, NULL);
if (rc) {
log_rdma_mr(ERR, "ib_post_send failed rc=%x\n", rc);
smbd_disconnect_rdma_connection(info);
goto done;
}
wait_for_completion(&smbdirect_mr->invalidate_done);
smbdirect_mr->need_invalidate = false;
} else
/*
* For remote invalidation, just set it to MR_INVALIDATED
* and defer to mr_recovery_work to recover the MR for next use
*/
smbdirect_mr->state = MR_INVALIDATED;
if (smbdirect_mr->state == MR_INVALIDATED) {
ib_dma_unmap_sg(
info->id->device, smbdirect_mr->sgt.sgl,
smbdirect_mr->sgt.nents,
smbdirect_mr->dir);
smbdirect_mr->state = MR_READY;
if (atomic_inc_return(&info->mr_ready_count) == 1)
wake_up_interruptible(&info->wait_mr);
} else
/*
* Schedule the work to do MR recovery for future I/Os MR
* recovery is slow and don't want it to block current I/O
*/
queue_work(info->workqueue, &info->mr_recovery_work);
done:
if (atomic_dec_and_test(&info->mr_used_count))
wake_up(&info->wait_for_mr_cleanup);
return rc;
}
static bool smb_set_sge(struct smb_extract_to_rdma *rdma,
struct page *lowest_page, size_t off, size_t len)
{
struct ib_sge *sge = &rdma->sge[rdma->nr_sge];
u64 addr;
addr = ib_dma_map_page(rdma->device, lowest_page,
off, len, rdma->direction);
if (ib_dma_mapping_error(rdma->device, addr))
return false;
sge->addr = addr;
sge->length = len;
sge->lkey = rdma->local_dma_lkey;
rdma->nr_sge++;
return true;
}
/*
* Extract page fragments from a BVEC-class iterator and add them to an RDMA
* element list. The pages are not pinned.
*/
static ssize_t smb_extract_bvec_to_rdma(struct iov_iter *iter,
struct smb_extract_to_rdma *rdma,
ssize_t maxsize)
{
const struct bio_vec *bv = iter->bvec;
unsigned long start = iter->iov_offset;
unsigned int i;
ssize_t ret = 0;
for (i = 0; i < iter->nr_segs; i++) {
size_t off, len;
len = bv[i].bv_len;
if (start >= len) {
start -= len;
continue;
}
len = min_t(size_t, maxsize, len - start);
off = bv[i].bv_offset + start;
if (!smb_set_sge(rdma, bv[i].bv_page, off, len))
return -EIO;
ret += len;
maxsize -= len;
if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0)
break;
start = 0;
}
return ret;
}
/*
* Extract fragments from a KVEC-class iterator and add them to an RDMA list.
* This can deal with vmalloc'd buffers as well as kmalloc'd or static buffers.
* The pages are not pinned.
*/
static ssize_t smb_extract_kvec_to_rdma(struct iov_iter *iter,
struct smb_extract_to_rdma *rdma,
ssize_t maxsize)
{
const struct kvec *kv = iter->kvec;
unsigned long start = iter->iov_offset;
unsigned int i;
ssize_t ret = 0;
for (i = 0; i < iter->nr_segs; i++) {
struct page *page;
unsigned long kaddr;
size_t off, len, seg;
len = kv[i].iov_len;
if (start >= len) {
start -= len;
continue;
}
kaddr = (unsigned long)kv[i].iov_base + start;
off = kaddr & ~PAGE_MASK;
len = min_t(size_t, maxsize, len - start);
kaddr &= PAGE_MASK;
maxsize -= len;
do {
seg = min_t(size_t, len, PAGE_SIZE - off);
if (is_vmalloc_or_module_addr((void *)kaddr))
page = vmalloc_to_page((void *)kaddr);
else
page = virt_to_page(kaddr);
if (!smb_set_sge(rdma, page, off, seg))
return -EIO;
ret += seg;
len -= seg;
kaddr += PAGE_SIZE;
off = 0;
} while (len > 0 && rdma->nr_sge < rdma->max_sge);
if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0)
break;
start = 0;
}
return ret;
}
/*
* Extract folio fragments from an XARRAY-class iterator and add them to an
* RDMA list. The folios are not pinned.
*/
static ssize_t smb_extract_xarray_to_rdma(struct iov_iter *iter,
struct smb_extract_to_rdma *rdma,
ssize_t maxsize)
{
struct xarray *xa = iter->xarray;
struct folio *folio;
loff_t start = iter->xarray_start + iter->iov_offset;
pgoff_t index = start / PAGE_SIZE;
ssize_t ret = 0;
size_t off, len;
XA_STATE(xas, xa, index);
rcu_read_lock();
xas_for_each(&xas, folio, ULONG_MAX) {
if (xas_retry(&xas, folio))
continue;
if (WARN_ON(xa_is_value(folio)))
break;
if (WARN_ON(folio_test_hugetlb(folio)))
break;
off = offset_in_folio(folio, start);
len = min_t(size_t, maxsize, folio_size(folio) - off);
if (!smb_set_sge(rdma, folio_page(folio, 0), off, len)) {
rcu_read_unlock();
return -EIO;
}
maxsize -= len;
ret += len;
if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0)
break;
}
rcu_read_unlock();
return ret;
}
/*
* Extract page fragments from up to the given amount of the source iterator
* and build up an RDMA list that refers to all of those bits. The RDMA list
* is appended to, up to the maximum number of elements set in the parameter
* block.
*
* The extracted page fragments are not pinned or ref'd in any way; if an
* IOVEC/UBUF-type iterator is to be used, it should be converted to a
* BVEC-type iterator and the pages pinned, ref'd or otherwise held in some
* way.
*/
static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len,
struct smb_extract_to_rdma *rdma)
{
ssize_t ret;
int before = rdma->nr_sge;
switch (iov_iter_type(iter)) {
case ITER_BVEC:
ret = smb_extract_bvec_to_rdma(iter, rdma, len);
break;
case ITER_KVEC:
ret = smb_extract_kvec_to_rdma(iter, rdma, len);
break;
case ITER_XARRAY:
ret = smb_extract_xarray_to_rdma(iter, rdma, len);
break;
default:
WARN_ON_ONCE(1);
return -EIO;
}
if (ret > 0) {
iov_iter_advance(iter, ret);
} else if (ret < 0) {
while (rdma->nr_sge > before) {
struct ib_sge *sge = &rdma->sge[rdma->nr_sge--];
ib_dma_unmap_single(rdma->device, sge->addr, sge->length,
rdma->direction);
sge->addr = 0;
}
}
return ret;
}