linux/drivers/nvme/target/rdma.c
Linus Torvalds 242b233198 RDMA 5.8 merge window pull request
A few large, long discussed works this time. The RNBD block driver has
 been posted for nearly two years now, and the removal of FMR has been a
 recurring discussion theme for a long time. The usual smattering of
 features and bug fixes.
 
 - Various small driver bugs fixes in rxe, mlx5, hfi1, and efa
 
 - Continuing driver cleanups in bnxt_re, hns
 
 - Big cleanup of mlx5 QP creation flows
 
 - More consistent use of src port and flow label when LAG is used and a
   mlx5 implementation
 
 - Additional set of cleanups for IB CM
 
 - 'RNBD' network block driver and target. This is a network block RDMA
   device specific to ionos's cloud environment. It brings strong multipath
   and resiliency capabilities.
 
 - Accelerated IPoIB for HFI1
 
 - QP/WQ/SRQ ioctl migration for uverbs, and support for multiple async fds
 
 - Support for exchanging the new IBTA defiend ECE data during RDMA CM
   exchanges
 
 - Removal of the very old and insecure FMR interface from all ULPs and
   drivers. FRWR should be preferred for at least a decade now.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma updates from Jason Gunthorpe:
 "A more active cycle than most of the recent past, with a few large,
  long discussed works this time.

  The RNBD block driver has been posted for nearly two years now, and
  flowing through RDMA due to it also introducing a new ULP.

  The removal of FMR has been a recurring discussion theme for a long
  time.

  And the usual smattering of features and bug fixes.

  Summary:

   - Various small driver bugs fixes in rxe, mlx5, hfi1, and efa

   - Continuing driver cleanups in bnxt_re, hns

   - Big cleanup of mlx5 QP creation flows

   - More consistent use of src port and flow label when LAG is used and
     a mlx5 implementation

   - Additional set of cleanups for IB CM

   - 'RNBD' network block driver and target. This is a network block
     RDMA device specific to ionos's cloud environment. It brings strong
     multipath and resiliency capabilities.

   - Accelerated IPoIB for HFI1

   - QP/WQ/SRQ ioctl migration for uverbs, and support for multiple
     async fds

   - Support for exchanging the new IBTA defiend ECE data during RDMA CM
     exchanges

   - Removal of the very old and insecure FMR interface from all ULPs
     and drivers. FRWR should be preferred for at least a decade now"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (247 commits)
  RDMA/cm: Spurious WARNING triggered in cm_destroy_id()
  RDMA/mlx5: Return ECE DC support
  RDMA/mlx5: Don't rely on FW to set zeros in ECE response
  RDMA/mlx5: Return an error if copy_to_user fails
  IB/hfi1: Use free_netdev() in hfi1_netdev_free()
  RDMA/hns: Uninitialized variable in modify_qp_init_to_rtr()
  RDMA/core: Move and rename trace_cm_id_create()
  IB/hfi1: Fix hfi1_netdev_rx_init() error handling
  RDMA: Remove 'max_map_per_fmr'
  RDMA: Remove 'max_fmr'
  RDMA/core: Remove FMR device ops
  RDMA/rdmavt: Remove FMR memory registration
  RDMA/mthca: Remove FMR support for memory registration
  RDMA/mlx4: Remove FMR support for memory registration
  RDMA/i40iw: Remove FMR leftovers
  RDMA/bnxt_re: Remove FMR leftovers
  RDMA/mlx5: Remove FMR leftovers
  RDMA/core: Remove FMR pool API
  RDMA/rds: Remove FMR support for memory registration
  RDMA/srp: Remove support for FMR memory registration
  ...
2020-06-05 14:05:57 -07:00

2057 lines
50 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* NVMe over Fabrics RDMA target.
* Copyright (c) 2015-2016 HGST, a Western Digital Company.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/atomic.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/nvme.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/inet.h>
#include <asm/unaligned.h>
#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <rdma/rw.h>
#include <rdma/ib_cm.h>
#include <linux/nvme-rdma.h>
#include "nvmet.h"
/*
* We allow at least 1 page, up to 4 SGEs, and up to 16KB of inline data
*/
#define NVMET_RDMA_DEFAULT_INLINE_DATA_SIZE PAGE_SIZE
#define NVMET_RDMA_MAX_INLINE_SGE 4
#define NVMET_RDMA_MAX_INLINE_DATA_SIZE max_t(int, SZ_16K, PAGE_SIZE)
/* Assume mpsmin == device_page_size == 4KB */
#define NVMET_RDMA_MAX_MDTS 8
#define NVMET_RDMA_MAX_METADATA_MDTS 5
struct nvmet_rdma_srq;
struct nvmet_rdma_cmd {
struct ib_sge sge[NVMET_RDMA_MAX_INLINE_SGE + 1];
struct ib_cqe cqe;
struct ib_recv_wr wr;
struct scatterlist inline_sg[NVMET_RDMA_MAX_INLINE_SGE];
struct nvme_command *nvme_cmd;
struct nvmet_rdma_queue *queue;
struct nvmet_rdma_srq *nsrq;
};
enum {
NVMET_RDMA_REQ_INLINE_DATA = (1 << 0),
NVMET_RDMA_REQ_INVALIDATE_RKEY = (1 << 1),
};
struct nvmet_rdma_rsp {
struct ib_sge send_sge;
struct ib_cqe send_cqe;
struct ib_send_wr send_wr;
struct nvmet_rdma_cmd *cmd;
struct nvmet_rdma_queue *queue;
struct ib_cqe read_cqe;
struct ib_cqe write_cqe;
struct rdma_rw_ctx rw;
struct nvmet_req req;
bool allocated;
u8 n_rdma;
u32 flags;
u32 invalidate_rkey;
struct list_head wait_list;
struct list_head free_list;
};
enum nvmet_rdma_queue_state {
NVMET_RDMA_Q_CONNECTING,
NVMET_RDMA_Q_LIVE,
NVMET_RDMA_Q_DISCONNECTING,
};
struct nvmet_rdma_queue {
struct rdma_cm_id *cm_id;
struct ib_qp *qp;
struct nvmet_port *port;
struct ib_cq *cq;
atomic_t sq_wr_avail;
struct nvmet_rdma_device *dev;
struct nvmet_rdma_srq *nsrq;
spinlock_t state_lock;
enum nvmet_rdma_queue_state state;
struct nvmet_cq nvme_cq;
struct nvmet_sq nvme_sq;
struct nvmet_rdma_rsp *rsps;
struct list_head free_rsps;
spinlock_t rsps_lock;
struct nvmet_rdma_cmd *cmds;
struct work_struct release_work;
struct list_head rsp_wait_list;
struct list_head rsp_wr_wait_list;
spinlock_t rsp_wr_wait_lock;
int idx;
int host_qid;
int comp_vector;
int recv_queue_size;
int send_queue_size;
struct list_head queue_list;
};
struct nvmet_rdma_port {
struct nvmet_port *nport;
struct sockaddr_storage addr;
struct rdma_cm_id *cm_id;
struct delayed_work repair_work;
};
struct nvmet_rdma_srq {
struct ib_srq *srq;
struct nvmet_rdma_cmd *cmds;
struct nvmet_rdma_device *ndev;
};
struct nvmet_rdma_device {
struct ib_device *device;
struct ib_pd *pd;
struct nvmet_rdma_srq **srqs;
int srq_count;
size_t srq_size;
struct kref ref;
struct list_head entry;
int inline_data_size;
int inline_page_count;
};
static bool nvmet_rdma_use_srq;
module_param_named(use_srq, nvmet_rdma_use_srq, bool, 0444);
MODULE_PARM_DESC(use_srq, "Use shared receive queue.");
static int srq_size_set(const char *val, const struct kernel_param *kp);
static const struct kernel_param_ops srq_size_ops = {
.set = srq_size_set,
.get = param_get_int,
};
static int nvmet_rdma_srq_size = 1024;
module_param_cb(srq_size, &srq_size_ops, &nvmet_rdma_srq_size, 0644);
MODULE_PARM_DESC(srq_size, "set Shared Receive Queue (SRQ) size, should >= 256 (default: 1024)");
static DEFINE_IDA(nvmet_rdma_queue_ida);
static LIST_HEAD(nvmet_rdma_queue_list);
static DEFINE_MUTEX(nvmet_rdma_queue_mutex);
static LIST_HEAD(device_list);
static DEFINE_MUTEX(device_list_mutex);
static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp);
static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_write_data_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_qp_event(struct ib_event *event, void *priv);
static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue);
static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_rsp *r);
static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_rsp *r);
static const struct nvmet_fabrics_ops nvmet_rdma_ops;
static int srq_size_set(const char *val, const struct kernel_param *kp)
{
int n = 0, ret;
ret = kstrtoint(val, 10, &n);
if (ret != 0 || n < 256)
return -EINVAL;
return param_set_int(val, kp);
}
static int num_pages(int len)
{
return 1 + (((len - 1) & PAGE_MASK) >> PAGE_SHIFT);
}
static inline bool nvmet_rdma_need_data_in(struct nvmet_rdma_rsp *rsp)
{
return nvme_is_write(rsp->req.cmd) &&
rsp->req.transfer_len &&
!(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
}
static inline bool nvmet_rdma_need_data_out(struct nvmet_rdma_rsp *rsp)
{
return !nvme_is_write(rsp->req.cmd) &&
rsp->req.transfer_len &&
!rsp->req.cqe->status &&
!(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
}
static inline struct nvmet_rdma_rsp *
nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue)
{
struct nvmet_rdma_rsp *rsp;
unsigned long flags;
spin_lock_irqsave(&queue->rsps_lock, flags);
rsp = list_first_entry_or_null(&queue->free_rsps,
struct nvmet_rdma_rsp, free_list);
if (likely(rsp))
list_del(&rsp->free_list);
spin_unlock_irqrestore(&queue->rsps_lock, flags);
if (unlikely(!rsp)) {
int ret;
rsp = kzalloc(sizeof(*rsp), GFP_KERNEL);
if (unlikely(!rsp))
return NULL;
ret = nvmet_rdma_alloc_rsp(queue->dev, rsp);
if (unlikely(ret)) {
kfree(rsp);
return NULL;
}
rsp->allocated = true;
}
return rsp;
}
static inline void
nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp)
{
unsigned long flags;
if (unlikely(rsp->allocated)) {
nvmet_rdma_free_rsp(rsp->queue->dev, rsp);
kfree(rsp);
return;
}
spin_lock_irqsave(&rsp->queue->rsps_lock, flags);
list_add_tail(&rsp->free_list, &rsp->queue->free_rsps);
spin_unlock_irqrestore(&rsp->queue->rsps_lock, flags);
}
static void nvmet_rdma_free_inline_pages(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *c)
{
struct scatterlist *sg;
struct ib_sge *sge;
int i;
if (!ndev->inline_data_size)
return;
sg = c->inline_sg;
sge = &c->sge[1];
for (i = 0; i < ndev->inline_page_count; i++, sg++, sge++) {
if (sge->length)
ib_dma_unmap_page(ndev->device, sge->addr,
sge->length, DMA_FROM_DEVICE);
if (sg_page(sg))
__free_page(sg_page(sg));
}
}
static int nvmet_rdma_alloc_inline_pages(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *c)
{
struct scatterlist *sg;
struct ib_sge *sge;
struct page *pg;
int len;
int i;
if (!ndev->inline_data_size)
return 0;
sg = c->inline_sg;
sg_init_table(sg, ndev->inline_page_count);
sge = &c->sge[1];
len = ndev->inline_data_size;
for (i = 0; i < ndev->inline_page_count; i++, sg++, sge++) {
pg = alloc_page(GFP_KERNEL);
if (!pg)
goto out_err;
sg_assign_page(sg, pg);
sge->addr = ib_dma_map_page(ndev->device,
pg, 0, PAGE_SIZE, DMA_FROM_DEVICE);
if (ib_dma_mapping_error(ndev->device, sge->addr))
goto out_err;
sge->length = min_t(int, len, PAGE_SIZE);
sge->lkey = ndev->pd->local_dma_lkey;
len -= sge->length;
}
return 0;
out_err:
for (; i >= 0; i--, sg--, sge--) {
if (sge->length)
ib_dma_unmap_page(ndev->device, sge->addr,
sge->length, DMA_FROM_DEVICE);
if (sg_page(sg))
__free_page(sg_page(sg));
}
return -ENOMEM;
}
static int nvmet_rdma_alloc_cmd(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *c, bool admin)
{
/* NVMe command / RDMA RECV */
c->nvme_cmd = kmalloc(sizeof(*c->nvme_cmd), GFP_KERNEL);
if (!c->nvme_cmd)
goto out;
c->sge[0].addr = ib_dma_map_single(ndev->device, c->nvme_cmd,
sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
if (ib_dma_mapping_error(ndev->device, c->sge[0].addr))
goto out_free_cmd;
c->sge[0].length = sizeof(*c->nvme_cmd);
c->sge[0].lkey = ndev->pd->local_dma_lkey;
if (!admin && nvmet_rdma_alloc_inline_pages(ndev, c))
goto out_unmap_cmd;
c->cqe.done = nvmet_rdma_recv_done;
c->wr.wr_cqe = &c->cqe;
c->wr.sg_list = c->sge;
c->wr.num_sge = admin ? 1 : ndev->inline_page_count + 1;
return 0;
out_unmap_cmd:
ib_dma_unmap_single(ndev->device, c->sge[0].addr,
sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
out_free_cmd:
kfree(c->nvme_cmd);
out:
return -ENOMEM;
}
static void nvmet_rdma_free_cmd(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *c, bool admin)
{
if (!admin)
nvmet_rdma_free_inline_pages(ndev, c);
ib_dma_unmap_single(ndev->device, c->sge[0].addr,
sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
kfree(c->nvme_cmd);
}
static struct nvmet_rdma_cmd *
nvmet_rdma_alloc_cmds(struct nvmet_rdma_device *ndev,
int nr_cmds, bool admin)
{
struct nvmet_rdma_cmd *cmds;
int ret = -EINVAL, i;
cmds = kcalloc(nr_cmds, sizeof(struct nvmet_rdma_cmd), GFP_KERNEL);
if (!cmds)
goto out;
for (i = 0; i < nr_cmds; i++) {
ret = nvmet_rdma_alloc_cmd(ndev, cmds + i, admin);
if (ret)
goto out_free;
}
return cmds;
out_free:
while (--i >= 0)
nvmet_rdma_free_cmd(ndev, cmds + i, admin);
kfree(cmds);
out:
return ERR_PTR(ret);
}
static void nvmet_rdma_free_cmds(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *cmds, int nr_cmds, bool admin)
{
int i;
for (i = 0; i < nr_cmds; i++)
nvmet_rdma_free_cmd(ndev, cmds + i, admin);
kfree(cmds);
}
static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_rsp *r)
{
/* NVMe CQE / RDMA SEND */
r->req.cqe = kmalloc(sizeof(*r->req.cqe), GFP_KERNEL);
if (!r->req.cqe)
goto out;
r->send_sge.addr = ib_dma_map_single(ndev->device, r->req.cqe,
sizeof(*r->req.cqe), DMA_TO_DEVICE);
if (ib_dma_mapping_error(ndev->device, r->send_sge.addr))
goto out_free_rsp;
r->req.p2p_client = &ndev->device->dev;
r->send_sge.length = sizeof(*r->req.cqe);
r->send_sge.lkey = ndev->pd->local_dma_lkey;
r->send_cqe.done = nvmet_rdma_send_done;
r->send_wr.wr_cqe = &r->send_cqe;
r->send_wr.sg_list = &r->send_sge;
r->send_wr.num_sge = 1;
r->send_wr.send_flags = IB_SEND_SIGNALED;
/* Data In / RDMA READ */
r->read_cqe.done = nvmet_rdma_read_data_done;
/* Data Out / RDMA WRITE */
r->write_cqe.done = nvmet_rdma_write_data_done;
return 0;
out_free_rsp:
kfree(r->req.cqe);
out:
return -ENOMEM;
}
static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_rsp *r)
{
ib_dma_unmap_single(ndev->device, r->send_sge.addr,
sizeof(*r->req.cqe), DMA_TO_DEVICE);
kfree(r->req.cqe);
}
static int
nvmet_rdma_alloc_rsps(struct nvmet_rdma_queue *queue)
{
struct nvmet_rdma_device *ndev = queue->dev;
int nr_rsps = queue->recv_queue_size * 2;
int ret = -EINVAL, i;
queue->rsps = kcalloc(nr_rsps, sizeof(struct nvmet_rdma_rsp),
GFP_KERNEL);
if (!queue->rsps)
goto out;
for (i = 0; i < nr_rsps; i++) {
struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
ret = nvmet_rdma_alloc_rsp(ndev, rsp);
if (ret)
goto out_free;
list_add_tail(&rsp->free_list, &queue->free_rsps);
}
return 0;
out_free:
while (--i >= 0) {
struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
list_del(&rsp->free_list);
nvmet_rdma_free_rsp(ndev, rsp);
}
kfree(queue->rsps);
out:
return ret;
}
static void nvmet_rdma_free_rsps(struct nvmet_rdma_queue *queue)
{
struct nvmet_rdma_device *ndev = queue->dev;
int i, nr_rsps = queue->recv_queue_size * 2;
for (i = 0; i < nr_rsps; i++) {
struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
list_del(&rsp->free_list);
nvmet_rdma_free_rsp(ndev, rsp);
}
kfree(queue->rsps);
}
static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *cmd)
{
int ret;
ib_dma_sync_single_for_device(ndev->device,
cmd->sge[0].addr, cmd->sge[0].length,
DMA_FROM_DEVICE);
if (cmd->nsrq)
ret = ib_post_srq_recv(cmd->nsrq->srq, &cmd->wr, NULL);
else
ret = ib_post_recv(cmd->queue->qp, &cmd->wr, NULL);
if (unlikely(ret))
pr_err("post_recv cmd failed\n");
return ret;
}
static void nvmet_rdma_process_wr_wait_list(struct nvmet_rdma_queue *queue)
{
spin_lock(&queue->rsp_wr_wait_lock);
while (!list_empty(&queue->rsp_wr_wait_list)) {
struct nvmet_rdma_rsp *rsp;
bool ret;
rsp = list_entry(queue->rsp_wr_wait_list.next,
struct nvmet_rdma_rsp, wait_list);
list_del(&rsp->wait_list);
spin_unlock(&queue->rsp_wr_wait_lock);
ret = nvmet_rdma_execute_command(rsp);
spin_lock(&queue->rsp_wr_wait_lock);
if (!ret) {
list_add(&rsp->wait_list, &queue->rsp_wr_wait_list);
break;
}
}
spin_unlock(&queue->rsp_wr_wait_lock);
}
static u16 nvmet_rdma_check_pi_status(struct ib_mr *sig_mr)
{
struct ib_mr_status mr_status;
int ret;
u16 status = 0;
ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
if (ret) {
pr_err("ib_check_mr_status failed, ret %d\n", ret);
return NVME_SC_INVALID_PI;
}
if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
switch (mr_status.sig_err.err_type) {
case IB_SIG_BAD_GUARD:
status = NVME_SC_GUARD_CHECK;
break;
case IB_SIG_BAD_REFTAG:
status = NVME_SC_REFTAG_CHECK;
break;
case IB_SIG_BAD_APPTAG:
status = NVME_SC_APPTAG_CHECK;
break;
}
pr_err("PI error found type %d expected 0x%x vs actual 0x%x\n",
mr_status.sig_err.err_type,
mr_status.sig_err.expected,
mr_status.sig_err.actual);
}
return status;
}
static void nvmet_rdma_set_sig_domain(struct blk_integrity *bi,
struct nvme_command *cmd, struct ib_sig_domain *domain,
u16 control, u8 pi_type)
{
domain->sig_type = IB_SIG_TYPE_T10_DIF;
domain->sig.dif.bg_type = IB_T10DIF_CRC;
domain->sig.dif.pi_interval = 1 << bi->interval_exp;
domain->sig.dif.ref_tag = le32_to_cpu(cmd->rw.reftag);
if (control & NVME_RW_PRINFO_PRCHK_REF)
domain->sig.dif.ref_remap = true;
domain->sig.dif.app_tag = le16_to_cpu(cmd->rw.apptag);
domain->sig.dif.apptag_check_mask = le16_to_cpu(cmd->rw.appmask);
domain->sig.dif.app_escape = true;
if (pi_type == NVME_NS_DPS_PI_TYPE3)
domain->sig.dif.ref_escape = true;
}
static void nvmet_rdma_set_sig_attrs(struct nvmet_req *req,
struct ib_sig_attrs *sig_attrs)
{
struct nvme_command *cmd = req->cmd;
u16 control = le16_to_cpu(cmd->rw.control);
u8 pi_type = req->ns->pi_type;
struct blk_integrity *bi;
bi = bdev_get_integrity(req->ns->bdev);
memset(sig_attrs, 0, sizeof(*sig_attrs));
if (control & NVME_RW_PRINFO_PRACT) {
/* for WRITE_INSERT/READ_STRIP no wire domain */
sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
nvmet_rdma_set_sig_domain(bi, cmd, &sig_attrs->mem, control,
pi_type);
/* Clear the PRACT bit since HCA will generate/verify the PI */
control &= ~NVME_RW_PRINFO_PRACT;
cmd->rw.control = cpu_to_le16(control);
/* PI is added by the HW */
req->transfer_len += req->metadata_len;
} else {
/* for WRITE_PASS/READ_PASS both wire/memory domains exist */
nvmet_rdma_set_sig_domain(bi, cmd, &sig_attrs->wire, control,
pi_type);
nvmet_rdma_set_sig_domain(bi, cmd, &sig_attrs->mem, control,
pi_type);
}
if (control & NVME_RW_PRINFO_PRCHK_REF)
sig_attrs->check_mask |= IB_SIG_CHECK_REFTAG;
if (control & NVME_RW_PRINFO_PRCHK_GUARD)
sig_attrs->check_mask |= IB_SIG_CHECK_GUARD;
if (control & NVME_RW_PRINFO_PRCHK_APP)
sig_attrs->check_mask |= IB_SIG_CHECK_APPTAG;
}
static int nvmet_rdma_rw_ctx_init(struct nvmet_rdma_rsp *rsp, u64 addr, u32 key,
struct ib_sig_attrs *sig_attrs)
{
struct rdma_cm_id *cm_id = rsp->queue->cm_id;
struct nvmet_req *req = &rsp->req;
int ret;
if (req->metadata_len)
ret = rdma_rw_ctx_signature_init(&rsp->rw, cm_id->qp,
cm_id->port_num, req->sg, req->sg_cnt,
req->metadata_sg, req->metadata_sg_cnt, sig_attrs,
addr, key, nvmet_data_dir(req));
else
ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num,
req->sg, req->sg_cnt, 0, addr, key,
nvmet_data_dir(req));
return ret;
}
static void nvmet_rdma_rw_ctx_destroy(struct nvmet_rdma_rsp *rsp)
{
struct rdma_cm_id *cm_id = rsp->queue->cm_id;
struct nvmet_req *req = &rsp->req;
if (req->metadata_len)
rdma_rw_ctx_destroy_signature(&rsp->rw, cm_id->qp,
cm_id->port_num, req->sg, req->sg_cnt,
req->metadata_sg, req->metadata_sg_cnt,
nvmet_data_dir(req));
else
rdma_rw_ctx_destroy(&rsp->rw, cm_id->qp, cm_id->port_num,
req->sg, req->sg_cnt, nvmet_data_dir(req));
}
static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp)
{
struct nvmet_rdma_queue *queue = rsp->queue;
atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
if (rsp->n_rdma)
nvmet_rdma_rw_ctx_destroy(rsp);
if (rsp->req.sg != rsp->cmd->inline_sg)
nvmet_req_free_sgls(&rsp->req);
if (unlikely(!list_empty_careful(&queue->rsp_wr_wait_list)))
nvmet_rdma_process_wr_wait_list(queue);
nvmet_rdma_put_rsp(rsp);
}
static void nvmet_rdma_error_comp(struct nvmet_rdma_queue *queue)
{
if (queue->nvme_sq.ctrl) {
nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
} else {
/*
* we didn't setup the controller yet in case
* of admin connect error, just disconnect and
* cleanup the queue
*/
nvmet_rdma_queue_disconnect(queue);
}
}
static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct nvmet_rdma_rsp *rsp =
container_of(wc->wr_cqe, struct nvmet_rdma_rsp, send_cqe);
struct nvmet_rdma_queue *queue = cq->cq_context;
nvmet_rdma_release_rsp(rsp);
if (unlikely(wc->status != IB_WC_SUCCESS &&
wc->status != IB_WC_WR_FLUSH_ERR)) {
pr_err("SEND for CQE 0x%p failed with status %s (%d).\n",
wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
nvmet_rdma_error_comp(queue);
}
}
static void nvmet_rdma_queue_response(struct nvmet_req *req)
{
struct nvmet_rdma_rsp *rsp =
container_of(req, struct nvmet_rdma_rsp, req);
struct rdma_cm_id *cm_id = rsp->queue->cm_id;
struct ib_send_wr *first_wr;
if (rsp->flags & NVMET_RDMA_REQ_INVALIDATE_RKEY) {
rsp->send_wr.opcode = IB_WR_SEND_WITH_INV;
rsp->send_wr.ex.invalidate_rkey = rsp->invalidate_rkey;
} else {
rsp->send_wr.opcode = IB_WR_SEND;
}
if (nvmet_rdma_need_data_out(rsp)) {
if (rsp->req.metadata_len)
first_wr = rdma_rw_ctx_wrs(&rsp->rw, cm_id->qp,
cm_id->port_num, &rsp->write_cqe, NULL);
else
first_wr = rdma_rw_ctx_wrs(&rsp->rw, cm_id->qp,
cm_id->port_num, NULL, &rsp->send_wr);
} else {
first_wr = &rsp->send_wr;
}
nvmet_rdma_post_recv(rsp->queue->dev, rsp->cmd);
ib_dma_sync_single_for_device(rsp->queue->dev->device,
rsp->send_sge.addr, rsp->send_sge.length,
DMA_TO_DEVICE);
if (unlikely(ib_post_send(cm_id->qp, first_wr, NULL))) {
pr_err("sending cmd response failed\n");
nvmet_rdma_release_rsp(rsp);
}
}
static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct nvmet_rdma_rsp *rsp =
container_of(wc->wr_cqe, struct nvmet_rdma_rsp, read_cqe);
struct nvmet_rdma_queue *queue = cq->cq_context;
u16 status = 0;
WARN_ON(rsp->n_rdma <= 0);
atomic_add(rsp->n_rdma, &queue->sq_wr_avail);
rsp->n_rdma = 0;
if (unlikely(wc->status != IB_WC_SUCCESS)) {
nvmet_rdma_rw_ctx_destroy(rsp);
nvmet_req_uninit(&rsp->req);
nvmet_rdma_release_rsp(rsp);
if (wc->status != IB_WC_WR_FLUSH_ERR) {
pr_info("RDMA READ for CQE 0x%p failed with status %s (%d).\n",
wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
nvmet_rdma_error_comp(queue);
}
return;
}
if (rsp->req.metadata_len)
status = nvmet_rdma_check_pi_status(rsp->rw.reg->mr);
nvmet_rdma_rw_ctx_destroy(rsp);
if (unlikely(status))
nvmet_req_complete(&rsp->req, status);
else
rsp->req.execute(&rsp->req);
}
static void nvmet_rdma_write_data_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct nvmet_rdma_rsp *rsp =
container_of(wc->wr_cqe, struct nvmet_rdma_rsp, write_cqe);
struct nvmet_rdma_queue *queue = cq->cq_context;
struct rdma_cm_id *cm_id = rsp->queue->cm_id;
u16 status;
if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
return;
WARN_ON(rsp->n_rdma <= 0);
atomic_add(rsp->n_rdma, &queue->sq_wr_avail);
rsp->n_rdma = 0;
if (unlikely(wc->status != IB_WC_SUCCESS)) {
nvmet_rdma_rw_ctx_destroy(rsp);
nvmet_req_uninit(&rsp->req);
nvmet_rdma_release_rsp(rsp);
if (wc->status != IB_WC_WR_FLUSH_ERR) {
pr_info("RDMA WRITE for CQE 0x%p failed with status %s (%d).\n",
wc->wr_cqe, ib_wc_status_msg(wc->status),
wc->status);
nvmet_rdma_error_comp(queue);
}
return;
}
/*
* Upon RDMA completion check the signature status
* - if succeeded send good NVMe response
* - if failed send bad NVMe response with appropriate error
*/
status = nvmet_rdma_check_pi_status(rsp->rw.reg->mr);
if (unlikely(status))
rsp->req.cqe->status = cpu_to_le16(status << 1);
nvmet_rdma_rw_ctx_destroy(rsp);
if (unlikely(ib_post_send(cm_id->qp, &rsp->send_wr, NULL))) {
pr_err("sending cmd response failed\n");
nvmet_rdma_release_rsp(rsp);
}
}
static void nvmet_rdma_use_inline_sg(struct nvmet_rdma_rsp *rsp, u32 len,
u64 off)
{
int sg_count = num_pages(len);
struct scatterlist *sg;
int i;
sg = rsp->cmd->inline_sg;
for (i = 0; i < sg_count; i++, sg++) {
if (i < sg_count - 1)
sg_unmark_end(sg);
else
sg_mark_end(sg);
sg->offset = off;
sg->length = min_t(int, len, PAGE_SIZE - off);
len -= sg->length;
if (!i)
off = 0;
}
rsp->req.sg = rsp->cmd->inline_sg;
rsp->req.sg_cnt = sg_count;
}
static u16 nvmet_rdma_map_sgl_inline(struct nvmet_rdma_rsp *rsp)
{
struct nvme_sgl_desc *sgl = &rsp->req.cmd->common.dptr.sgl;
u64 off = le64_to_cpu(sgl->addr);
u32 len = le32_to_cpu(sgl->length);
if (!nvme_is_write(rsp->req.cmd)) {
rsp->req.error_loc =
offsetof(struct nvme_common_command, opcode);
return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
}
if (off + len > rsp->queue->dev->inline_data_size) {
pr_err("invalid inline data offset!\n");
return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR;
}
/* no data command? */
if (!len)
return 0;
nvmet_rdma_use_inline_sg(rsp, len, off);
rsp->flags |= NVMET_RDMA_REQ_INLINE_DATA;
rsp->req.transfer_len += len;
return 0;
}
static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
struct nvme_keyed_sgl_desc *sgl, bool invalidate)
{
u64 addr = le64_to_cpu(sgl->addr);
u32 key = get_unaligned_le32(sgl->key);
struct ib_sig_attrs sig_attrs;
int ret;
rsp->req.transfer_len = get_unaligned_le24(sgl->length);
/* no data command? */
if (!rsp->req.transfer_len)
return 0;
if (rsp->req.metadata_len)
nvmet_rdma_set_sig_attrs(&rsp->req, &sig_attrs);
ret = nvmet_req_alloc_sgls(&rsp->req);
if (unlikely(ret < 0))
goto error_out;
ret = nvmet_rdma_rw_ctx_init(rsp, addr, key, &sig_attrs);
if (unlikely(ret < 0))
goto error_out;
rsp->n_rdma += ret;
if (invalidate) {
rsp->invalidate_rkey = key;
rsp->flags |= NVMET_RDMA_REQ_INVALIDATE_RKEY;
}
return 0;
error_out:
rsp->req.transfer_len = 0;
return NVME_SC_INTERNAL;
}
static u16 nvmet_rdma_map_sgl(struct nvmet_rdma_rsp *rsp)
{
struct nvme_keyed_sgl_desc *sgl = &rsp->req.cmd->common.dptr.ksgl;
switch (sgl->type >> 4) {
case NVME_SGL_FMT_DATA_DESC:
switch (sgl->type & 0xf) {
case NVME_SGL_FMT_OFFSET:
return nvmet_rdma_map_sgl_inline(rsp);
default:
pr_err("invalid SGL subtype: %#x\n", sgl->type);
rsp->req.error_loc =
offsetof(struct nvme_common_command, dptr);
return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
}
case NVME_KEY_SGL_FMT_DATA_DESC:
switch (sgl->type & 0xf) {
case NVME_SGL_FMT_ADDRESS | NVME_SGL_FMT_INVALIDATE:
return nvmet_rdma_map_sgl_keyed(rsp, sgl, true);
case NVME_SGL_FMT_ADDRESS:
return nvmet_rdma_map_sgl_keyed(rsp, sgl, false);
default:
pr_err("invalid SGL subtype: %#x\n", sgl->type);
rsp->req.error_loc =
offsetof(struct nvme_common_command, dptr);
return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
}
default:
pr_err("invalid SGL type: %#x\n", sgl->type);
rsp->req.error_loc = offsetof(struct nvme_common_command, dptr);
return NVME_SC_SGL_INVALID_TYPE | NVME_SC_DNR;
}
}
static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp)
{
struct nvmet_rdma_queue *queue = rsp->queue;
if (unlikely(atomic_sub_return(1 + rsp->n_rdma,
&queue->sq_wr_avail) < 0)) {
pr_debug("IB send queue full (needed %d): queue %u cntlid %u\n",
1 + rsp->n_rdma, queue->idx,
queue->nvme_sq.ctrl->cntlid);
atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
return false;
}
if (nvmet_rdma_need_data_in(rsp)) {
if (rdma_rw_ctx_post(&rsp->rw, queue->qp,
queue->cm_id->port_num, &rsp->read_cqe, NULL))
nvmet_req_complete(&rsp->req, NVME_SC_DATA_XFER_ERROR);
} else {
rsp->req.execute(&rsp->req);
}
return true;
}
static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue,
struct nvmet_rdma_rsp *cmd)
{
u16 status;
ib_dma_sync_single_for_cpu(queue->dev->device,
cmd->cmd->sge[0].addr, cmd->cmd->sge[0].length,
DMA_FROM_DEVICE);
ib_dma_sync_single_for_cpu(queue->dev->device,
cmd->send_sge.addr, cmd->send_sge.length,
DMA_TO_DEVICE);
if (!nvmet_req_init(&cmd->req, &queue->nvme_cq,
&queue->nvme_sq, &nvmet_rdma_ops))
return;
status = nvmet_rdma_map_sgl(cmd);
if (status)
goto out_err;
if (unlikely(!nvmet_rdma_execute_command(cmd))) {
spin_lock(&queue->rsp_wr_wait_lock);
list_add_tail(&cmd->wait_list, &queue->rsp_wr_wait_list);
spin_unlock(&queue->rsp_wr_wait_lock);
}
return;
out_err:
nvmet_req_complete(&cmd->req, status);
}
static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
{
struct nvmet_rdma_cmd *cmd =
container_of(wc->wr_cqe, struct nvmet_rdma_cmd, cqe);
struct nvmet_rdma_queue *queue = cq->cq_context;
struct nvmet_rdma_rsp *rsp;
if (unlikely(wc->status != IB_WC_SUCCESS)) {
if (wc->status != IB_WC_WR_FLUSH_ERR) {
pr_err("RECV for CQE 0x%p failed with status %s (%d)\n",
wc->wr_cqe, ib_wc_status_msg(wc->status),
wc->status);
nvmet_rdma_error_comp(queue);
}
return;
}
if (unlikely(wc->byte_len < sizeof(struct nvme_command))) {
pr_err("Ctrl Fatal Error: capsule size less than 64 bytes\n");
nvmet_rdma_error_comp(queue);
return;
}
cmd->queue = queue;
rsp = nvmet_rdma_get_rsp(queue);
if (unlikely(!rsp)) {
/*
* we get here only under memory pressure,
* silently drop and have the host retry
* as we can't even fail it.
*/
nvmet_rdma_post_recv(queue->dev, cmd);
return;
}
rsp->queue = queue;
rsp->cmd = cmd;
rsp->flags = 0;
rsp->req.cmd = cmd->nvme_cmd;
rsp->req.port = queue->port;
rsp->n_rdma = 0;
if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) {
unsigned long flags;
spin_lock_irqsave(&queue->state_lock, flags);
if (queue->state == NVMET_RDMA_Q_CONNECTING)
list_add_tail(&rsp->wait_list, &queue->rsp_wait_list);
else
nvmet_rdma_put_rsp(rsp);
spin_unlock_irqrestore(&queue->state_lock, flags);
return;
}
nvmet_rdma_handle_command(queue, rsp);
}
static void nvmet_rdma_destroy_srq(struct nvmet_rdma_srq *nsrq)
{
nvmet_rdma_free_cmds(nsrq->ndev, nsrq->cmds, nsrq->ndev->srq_size,
false);
ib_destroy_srq(nsrq->srq);
kfree(nsrq);
}
static void nvmet_rdma_destroy_srqs(struct nvmet_rdma_device *ndev)
{
int i;
if (!ndev->srqs)
return;
for (i = 0; i < ndev->srq_count; i++)
nvmet_rdma_destroy_srq(ndev->srqs[i]);
kfree(ndev->srqs);
}
static struct nvmet_rdma_srq *
nvmet_rdma_init_srq(struct nvmet_rdma_device *ndev)
{
struct ib_srq_init_attr srq_attr = { NULL, };
size_t srq_size = ndev->srq_size;
struct nvmet_rdma_srq *nsrq;
struct ib_srq *srq;
int ret, i;
nsrq = kzalloc(sizeof(*nsrq), GFP_KERNEL);
if (!nsrq)
return ERR_PTR(-ENOMEM);
srq_attr.attr.max_wr = srq_size;
srq_attr.attr.max_sge = 1 + ndev->inline_page_count;
srq_attr.attr.srq_limit = 0;
srq_attr.srq_type = IB_SRQT_BASIC;
srq = ib_create_srq(ndev->pd, &srq_attr);
if (IS_ERR(srq)) {
ret = PTR_ERR(srq);
goto out_free;
}
nsrq->cmds = nvmet_rdma_alloc_cmds(ndev, srq_size, false);
if (IS_ERR(nsrq->cmds)) {
ret = PTR_ERR(nsrq->cmds);
goto out_destroy_srq;
}
nsrq->srq = srq;
nsrq->ndev = ndev;
for (i = 0; i < srq_size; i++) {
nsrq->cmds[i].nsrq = nsrq;
ret = nvmet_rdma_post_recv(ndev, &nsrq->cmds[i]);
if (ret)
goto out_free_cmds;
}
return nsrq;
out_free_cmds:
nvmet_rdma_free_cmds(ndev, nsrq->cmds, srq_size, false);
out_destroy_srq:
ib_destroy_srq(srq);
out_free:
kfree(nsrq);
return ERR_PTR(ret);
}
static int nvmet_rdma_init_srqs(struct nvmet_rdma_device *ndev)
{
int i, ret;
if (!ndev->device->attrs.max_srq_wr || !ndev->device->attrs.max_srq) {
/*
* If SRQs aren't supported we just go ahead and use normal
* non-shared receive queues.
*/
pr_info("SRQ requested but not supported.\n");
return 0;
}
ndev->srq_size = min(ndev->device->attrs.max_srq_wr,
nvmet_rdma_srq_size);
ndev->srq_count = min(ndev->device->num_comp_vectors,
ndev->device->attrs.max_srq);
ndev->srqs = kcalloc(ndev->srq_count, sizeof(*ndev->srqs), GFP_KERNEL);
if (!ndev->srqs)
return -ENOMEM;
for (i = 0; i < ndev->srq_count; i++) {
ndev->srqs[i] = nvmet_rdma_init_srq(ndev);
if (IS_ERR(ndev->srqs[i])) {
ret = PTR_ERR(ndev->srqs[i]);
goto err_srq;
}
}
return 0;
err_srq:
while (--i >= 0)
nvmet_rdma_destroy_srq(ndev->srqs[i]);
kfree(ndev->srqs);
return ret;
}
static void nvmet_rdma_free_dev(struct kref *ref)
{
struct nvmet_rdma_device *ndev =
container_of(ref, struct nvmet_rdma_device, ref);
mutex_lock(&device_list_mutex);
list_del(&ndev->entry);
mutex_unlock(&device_list_mutex);
nvmet_rdma_destroy_srqs(ndev);
ib_dealloc_pd(ndev->pd);
kfree(ndev);
}
static struct nvmet_rdma_device *
nvmet_rdma_find_get_device(struct rdma_cm_id *cm_id)
{
struct nvmet_rdma_port *port = cm_id->context;
struct nvmet_port *nport = port->nport;
struct nvmet_rdma_device *ndev;
int inline_page_count;
int inline_sge_count;
int ret;
mutex_lock(&device_list_mutex);
list_for_each_entry(ndev, &device_list, entry) {
if (ndev->device->node_guid == cm_id->device->node_guid &&
kref_get_unless_zero(&ndev->ref))
goto out_unlock;
}
ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
if (!ndev)
goto out_err;
inline_page_count = num_pages(nport->inline_data_size);
inline_sge_count = max(cm_id->device->attrs.max_sge_rd,
cm_id->device->attrs.max_recv_sge) - 1;
if (inline_page_count > inline_sge_count) {
pr_warn("inline_data_size %d cannot be supported by device %s. Reducing to %lu.\n",
nport->inline_data_size, cm_id->device->name,
inline_sge_count * PAGE_SIZE);
nport->inline_data_size = inline_sge_count * PAGE_SIZE;
inline_page_count = inline_sge_count;
}
ndev->inline_data_size = nport->inline_data_size;
ndev->inline_page_count = inline_page_count;
ndev->device = cm_id->device;
kref_init(&ndev->ref);
ndev->pd = ib_alloc_pd(ndev->device, 0);
if (IS_ERR(ndev->pd))
goto out_free_dev;
if (nvmet_rdma_use_srq) {
ret = nvmet_rdma_init_srqs(ndev);
if (ret)
goto out_free_pd;
}
list_add(&ndev->entry, &device_list);
out_unlock:
mutex_unlock(&device_list_mutex);
pr_debug("added %s.\n", ndev->device->name);
return ndev;
out_free_pd:
ib_dealloc_pd(ndev->pd);
out_free_dev:
kfree(ndev);
out_err:
mutex_unlock(&device_list_mutex);
return NULL;
}
static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
{
struct ib_qp_init_attr qp_attr;
struct nvmet_rdma_device *ndev = queue->dev;
int nr_cqe, ret, i, factor;
/*
* Reserve CQ slots for RECV + RDMA_READ/RDMA_WRITE + RDMA_SEND.
*/
nr_cqe = queue->recv_queue_size + 2 * queue->send_queue_size;
queue->cq = ib_alloc_cq(ndev->device, queue,
nr_cqe + 1, queue->comp_vector,
IB_POLL_WORKQUEUE);
if (IS_ERR(queue->cq)) {
ret = PTR_ERR(queue->cq);
pr_err("failed to create CQ cqe= %d ret= %d\n",
nr_cqe + 1, ret);
goto out;
}
memset(&qp_attr, 0, sizeof(qp_attr));
qp_attr.qp_context = queue;
qp_attr.event_handler = nvmet_rdma_qp_event;
qp_attr.send_cq = queue->cq;
qp_attr.recv_cq = queue->cq;
qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
qp_attr.qp_type = IB_QPT_RC;
/* +1 for drain */
qp_attr.cap.max_send_wr = queue->send_queue_size + 1;
factor = rdma_rw_mr_factor(ndev->device, queue->cm_id->port_num,
1 << NVMET_RDMA_MAX_MDTS);
qp_attr.cap.max_rdma_ctxs = queue->send_queue_size * factor;
qp_attr.cap.max_send_sge = max(ndev->device->attrs.max_sge_rd,
ndev->device->attrs.max_send_sge);
if (queue->nsrq) {
qp_attr.srq = queue->nsrq->srq;
} else {
/* +1 for drain */
qp_attr.cap.max_recv_wr = 1 + queue->recv_queue_size;
qp_attr.cap.max_recv_sge = 1 + ndev->inline_page_count;
}
if (queue->port->pi_enable && queue->host_qid)
qp_attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN;
ret = rdma_create_qp(queue->cm_id, ndev->pd, &qp_attr);
if (ret) {
pr_err("failed to create_qp ret= %d\n", ret);
goto err_destroy_cq;
}
queue->qp = queue->cm_id->qp;
atomic_set(&queue->sq_wr_avail, qp_attr.cap.max_send_wr);
pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
__func__, queue->cq->cqe, qp_attr.cap.max_send_sge,
qp_attr.cap.max_send_wr, queue->cm_id);
if (!queue->nsrq) {
for (i = 0; i < queue->recv_queue_size; i++) {
queue->cmds[i].queue = queue;
ret = nvmet_rdma_post_recv(ndev, &queue->cmds[i]);
if (ret)
goto err_destroy_qp;
}
}
out:
return ret;
err_destroy_qp:
rdma_destroy_qp(queue->cm_id);
err_destroy_cq:
ib_free_cq(queue->cq);
goto out;
}
static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue)
{
ib_drain_qp(queue->qp);
if (queue->cm_id)
rdma_destroy_id(queue->cm_id);
ib_destroy_qp(queue->qp);
ib_free_cq(queue->cq);
}
static void nvmet_rdma_free_queue(struct nvmet_rdma_queue *queue)
{
pr_debug("freeing queue %d\n", queue->idx);
nvmet_sq_destroy(&queue->nvme_sq);
nvmet_rdma_destroy_queue_ib(queue);
if (!queue->nsrq) {
nvmet_rdma_free_cmds(queue->dev, queue->cmds,
queue->recv_queue_size,
!queue->host_qid);
}
nvmet_rdma_free_rsps(queue);
ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
kfree(queue);
}
static void nvmet_rdma_release_queue_work(struct work_struct *w)
{
struct nvmet_rdma_queue *queue =
container_of(w, struct nvmet_rdma_queue, release_work);
struct nvmet_rdma_device *dev = queue->dev;
nvmet_rdma_free_queue(queue);
kref_put(&dev->ref, nvmet_rdma_free_dev);
}
static int
nvmet_rdma_parse_cm_connect_req(struct rdma_conn_param *conn,
struct nvmet_rdma_queue *queue)
{
struct nvme_rdma_cm_req *req;
req = (struct nvme_rdma_cm_req *)conn->private_data;
if (!req || conn->private_data_len == 0)
return NVME_RDMA_CM_INVALID_LEN;
if (le16_to_cpu(req->recfmt) != NVME_RDMA_CM_FMT_1_0)
return NVME_RDMA_CM_INVALID_RECFMT;
queue->host_qid = le16_to_cpu(req->qid);
/*
* req->hsqsize corresponds to our recv queue size plus 1
* req->hrqsize corresponds to our send queue size
*/
queue->recv_queue_size = le16_to_cpu(req->hsqsize) + 1;
queue->send_queue_size = le16_to_cpu(req->hrqsize);
if (!queue->host_qid && queue->recv_queue_size > NVME_AQ_DEPTH)
return NVME_RDMA_CM_INVALID_HSQSIZE;
/* XXX: Should we enforce some kind of max for IO queues? */
return 0;
}
static int nvmet_rdma_cm_reject(struct rdma_cm_id *cm_id,
enum nvme_rdma_cm_status status)
{
struct nvme_rdma_cm_rej rej;
pr_debug("rejecting connect request: status %d (%s)\n",
status, nvme_rdma_cm_msg(status));
rej.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
rej.sts = cpu_to_le16(status);
return rdma_reject(cm_id, (void *)&rej, sizeof(rej),
IB_CM_REJ_CONSUMER_DEFINED);
}
static struct nvmet_rdma_queue *
nvmet_rdma_alloc_queue(struct nvmet_rdma_device *ndev,
struct rdma_cm_id *cm_id,
struct rdma_cm_event *event)
{
struct nvmet_rdma_port *port = cm_id->context;
struct nvmet_rdma_queue *queue;
int ret;
queue = kzalloc(sizeof(*queue), GFP_KERNEL);
if (!queue) {
ret = NVME_RDMA_CM_NO_RSC;
goto out_reject;
}
ret = nvmet_sq_init(&queue->nvme_sq);
if (ret) {
ret = NVME_RDMA_CM_NO_RSC;
goto out_free_queue;
}
ret = nvmet_rdma_parse_cm_connect_req(&event->param.conn, queue);
if (ret)
goto out_destroy_sq;
/*
* Schedules the actual release because calling rdma_destroy_id from
* inside a CM callback would trigger a deadlock. (great API design..)
*/
INIT_WORK(&queue->release_work, nvmet_rdma_release_queue_work);
queue->dev = ndev;
queue->cm_id = cm_id;
queue->port = port->nport;
spin_lock_init(&queue->state_lock);
queue->state = NVMET_RDMA_Q_CONNECTING;
INIT_LIST_HEAD(&queue->rsp_wait_list);
INIT_LIST_HEAD(&queue->rsp_wr_wait_list);
spin_lock_init(&queue->rsp_wr_wait_lock);
INIT_LIST_HEAD(&queue->free_rsps);
spin_lock_init(&queue->rsps_lock);
INIT_LIST_HEAD(&queue->queue_list);
queue->idx = ida_simple_get(&nvmet_rdma_queue_ida, 0, 0, GFP_KERNEL);
if (queue->idx < 0) {
ret = NVME_RDMA_CM_NO_RSC;
goto out_destroy_sq;
}
/*
* Spread the io queues across completion vectors,
* but still keep all admin queues on vector 0.
*/
queue->comp_vector = !queue->host_qid ? 0 :
queue->idx % ndev->device->num_comp_vectors;
ret = nvmet_rdma_alloc_rsps(queue);
if (ret) {
ret = NVME_RDMA_CM_NO_RSC;
goto out_ida_remove;
}
if (ndev->srqs) {
queue->nsrq = ndev->srqs[queue->comp_vector % ndev->srq_count];
} else {
queue->cmds = nvmet_rdma_alloc_cmds(ndev,
queue->recv_queue_size,
!queue->host_qid);
if (IS_ERR(queue->cmds)) {
ret = NVME_RDMA_CM_NO_RSC;
goto out_free_responses;
}
}
ret = nvmet_rdma_create_queue_ib(queue);
if (ret) {
pr_err("%s: creating RDMA queue failed (%d).\n",
__func__, ret);
ret = NVME_RDMA_CM_NO_RSC;
goto out_free_cmds;
}
return queue;
out_free_cmds:
if (!queue->nsrq) {
nvmet_rdma_free_cmds(queue->dev, queue->cmds,
queue->recv_queue_size,
!queue->host_qid);
}
out_free_responses:
nvmet_rdma_free_rsps(queue);
out_ida_remove:
ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
out_destroy_sq:
nvmet_sq_destroy(&queue->nvme_sq);
out_free_queue:
kfree(queue);
out_reject:
nvmet_rdma_cm_reject(cm_id, ret);
return NULL;
}
static void nvmet_rdma_qp_event(struct ib_event *event, void *priv)
{
struct nvmet_rdma_queue *queue = priv;
switch (event->event) {
case IB_EVENT_COMM_EST:
rdma_notify(queue->cm_id, event->event);
break;
case IB_EVENT_QP_LAST_WQE_REACHED:
pr_debug("received last WQE reached event for queue=0x%p\n",
queue);
break;
default:
pr_err("received IB QP event: %s (%d)\n",
ib_event_msg(event->event), event->event);
break;
}
}
static int nvmet_rdma_cm_accept(struct rdma_cm_id *cm_id,
struct nvmet_rdma_queue *queue,
struct rdma_conn_param *p)
{
struct rdma_conn_param param = { };
struct nvme_rdma_cm_rep priv = { };
int ret = -ENOMEM;
param.rnr_retry_count = 7;
param.flow_control = 1;
param.initiator_depth = min_t(u8, p->initiator_depth,
queue->dev->device->attrs.max_qp_init_rd_atom);
param.private_data = &priv;
param.private_data_len = sizeof(priv);
priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
priv.crqsize = cpu_to_le16(queue->recv_queue_size);
ret = rdma_accept(cm_id, &param);
if (ret)
pr_err("rdma_accept failed (error code = %d)\n", ret);
return ret;
}
static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id,
struct rdma_cm_event *event)
{
struct nvmet_rdma_device *ndev;
struct nvmet_rdma_queue *queue;
int ret = -EINVAL;
ndev = nvmet_rdma_find_get_device(cm_id);
if (!ndev) {
nvmet_rdma_cm_reject(cm_id, NVME_RDMA_CM_NO_RSC);
return -ECONNREFUSED;
}
queue = nvmet_rdma_alloc_queue(ndev, cm_id, event);
if (!queue) {
ret = -ENOMEM;
goto put_device;
}
if (queue->host_qid == 0) {
/* Let inflight controller teardown complete */
flush_scheduled_work();
}
ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn);
if (ret) {
/*
* Don't destroy the cm_id in free path, as we implicitly
* destroy the cm_id here with non-zero ret code.
*/
queue->cm_id = NULL;
goto free_queue;
}
mutex_lock(&nvmet_rdma_queue_mutex);
list_add_tail(&queue->queue_list, &nvmet_rdma_queue_list);
mutex_unlock(&nvmet_rdma_queue_mutex);
return 0;
free_queue:
nvmet_rdma_free_queue(queue);
put_device:
kref_put(&ndev->ref, nvmet_rdma_free_dev);
return ret;
}
static void nvmet_rdma_queue_established(struct nvmet_rdma_queue *queue)
{
unsigned long flags;
spin_lock_irqsave(&queue->state_lock, flags);
if (queue->state != NVMET_RDMA_Q_CONNECTING) {
pr_warn("trying to establish a connected queue\n");
goto out_unlock;
}
queue->state = NVMET_RDMA_Q_LIVE;
while (!list_empty(&queue->rsp_wait_list)) {
struct nvmet_rdma_rsp *cmd;
cmd = list_first_entry(&queue->rsp_wait_list,
struct nvmet_rdma_rsp, wait_list);
list_del(&cmd->wait_list);
spin_unlock_irqrestore(&queue->state_lock, flags);
nvmet_rdma_handle_command(queue, cmd);
spin_lock_irqsave(&queue->state_lock, flags);
}
out_unlock:
spin_unlock_irqrestore(&queue->state_lock, flags);
}
static void __nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
{
bool disconnect = false;
unsigned long flags;
pr_debug("cm_id= %p queue->state= %d\n", queue->cm_id, queue->state);
spin_lock_irqsave(&queue->state_lock, flags);
switch (queue->state) {
case NVMET_RDMA_Q_CONNECTING:
case NVMET_RDMA_Q_LIVE:
queue->state = NVMET_RDMA_Q_DISCONNECTING;
disconnect = true;
break;
case NVMET_RDMA_Q_DISCONNECTING:
break;
}
spin_unlock_irqrestore(&queue->state_lock, flags);
if (disconnect) {
rdma_disconnect(queue->cm_id);
schedule_work(&queue->release_work);
}
}
static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
{
bool disconnect = false;
mutex_lock(&nvmet_rdma_queue_mutex);
if (!list_empty(&queue->queue_list)) {
list_del_init(&queue->queue_list);
disconnect = true;
}
mutex_unlock(&nvmet_rdma_queue_mutex);
if (disconnect)
__nvmet_rdma_queue_disconnect(queue);
}
static void nvmet_rdma_queue_connect_fail(struct rdma_cm_id *cm_id,
struct nvmet_rdma_queue *queue)
{
WARN_ON_ONCE(queue->state != NVMET_RDMA_Q_CONNECTING);
mutex_lock(&nvmet_rdma_queue_mutex);
if (!list_empty(&queue->queue_list))
list_del_init(&queue->queue_list);
mutex_unlock(&nvmet_rdma_queue_mutex);
pr_err("failed to connect queue %d\n", queue->idx);
schedule_work(&queue->release_work);
}
/**
* nvme_rdma_device_removal() - Handle RDMA device removal
* @cm_id: rdma_cm id, used for nvmet port
* @queue: nvmet rdma queue (cm id qp_context)
*
* DEVICE_REMOVAL event notifies us that the RDMA device is about
* to unplug. Note that this event can be generated on a normal
* queue cm_id and/or a device bound listener cm_id (where in this
* case queue will be null).
*
* We registered an ib_client to handle device removal for queues,
* so we only need to handle the listening port cm_ids. In this case
* we nullify the priv to prevent double cm_id destruction and destroying
* the cm_id implicitely by returning a non-zero rc to the callout.
*/
static int nvmet_rdma_device_removal(struct rdma_cm_id *cm_id,
struct nvmet_rdma_queue *queue)
{
struct nvmet_rdma_port *port;
if (queue) {
/*
* This is a queue cm_id. we have registered
* an ib_client to handle queues removal
* so don't interfear and just return.
*/
return 0;
}
port = cm_id->context;
/*
* This is a listener cm_id. Make sure that
* future remove_port won't invoke a double
* cm_id destroy. use atomic xchg to make sure
* we don't compete with remove_port.
*/
if (xchg(&port->cm_id, NULL) != cm_id)
return 0;
/*
* We need to return 1 so that the core will destroy
* it's own ID. What a great API design..
*/
return 1;
}
static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id,
struct rdma_cm_event *event)
{
struct nvmet_rdma_queue *queue = NULL;
int ret = 0;
if (cm_id->qp)
queue = cm_id->qp->qp_context;
pr_debug("%s (%d): status %d id %p\n",
rdma_event_msg(event->event), event->event,
event->status, cm_id);
switch (event->event) {
case RDMA_CM_EVENT_CONNECT_REQUEST:
ret = nvmet_rdma_queue_connect(cm_id, event);
break;
case RDMA_CM_EVENT_ESTABLISHED:
nvmet_rdma_queue_established(queue);
break;
case RDMA_CM_EVENT_ADDR_CHANGE:
if (!queue) {
struct nvmet_rdma_port *port = cm_id->context;
schedule_delayed_work(&port->repair_work, 0);
break;
}
/* FALLTHROUGH */
case RDMA_CM_EVENT_DISCONNECTED:
case RDMA_CM_EVENT_TIMEWAIT_EXIT:
nvmet_rdma_queue_disconnect(queue);
break;
case RDMA_CM_EVENT_DEVICE_REMOVAL:
ret = nvmet_rdma_device_removal(cm_id, queue);
break;
case RDMA_CM_EVENT_REJECTED:
pr_debug("Connection rejected: %s\n",
rdma_reject_msg(cm_id, event->status));
/* FALLTHROUGH */
case RDMA_CM_EVENT_UNREACHABLE:
case RDMA_CM_EVENT_CONNECT_ERROR:
nvmet_rdma_queue_connect_fail(cm_id, queue);
break;
default:
pr_err("received unrecognized RDMA CM event %d\n",
event->event);
break;
}
return ret;
}
static void nvmet_rdma_delete_ctrl(struct nvmet_ctrl *ctrl)
{
struct nvmet_rdma_queue *queue;
restart:
mutex_lock(&nvmet_rdma_queue_mutex);
list_for_each_entry(queue, &nvmet_rdma_queue_list, queue_list) {
if (queue->nvme_sq.ctrl == ctrl) {
list_del_init(&queue->queue_list);
mutex_unlock(&nvmet_rdma_queue_mutex);
__nvmet_rdma_queue_disconnect(queue);
goto restart;
}
}
mutex_unlock(&nvmet_rdma_queue_mutex);
}
static void nvmet_rdma_disable_port(struct nvmet_rdma_port *port)
{
struct rdma_cm_id *cm_id = xchg(&port->cm_id, NULL);
if (cm_id)
rdma_destroy_id(cm_id);
}
static int nvmet_rdma_enable_port(struct nvmet_rdma_port *port)
{
struct sockaddr *addr = (struct sockaddr *)&port->addr;
struct rdma_cm_id *cm_id;
int ret;
cm_id = rdma_create_id(&init_net, nvmet_rdma_cm_handler, port,
RDMA_PS_TCP, IB_QPT_RC);
if (IS_ERR(cm_id)) {
pr_err("CM ID creation failed\n");
return PTR_ERR(cm_id);
}
/*
* Allow both IPv4 and IPv6 sockets to bind a single port
* at the same time.
*/
ret = rdma_set_afonly(cm_id, 1);
if (ret) {
pr_err("rdma_set_afonly failed (%d)\n", ret);
goto out_destroy_id;
}
ret = rdma_bind_addr(cm_id, addr);
if (ret) {
pr_err("binding CM ID to %pISpcs failed (%d)\n", addr, ret);
goto out_destroy_id;
}
ret = rdma_listen(cm_id, 128);
if (ret) {
pr_err("listening to %pISpcs failed (%d)\n", addr, ret);
goto out_destroy_id;
}
if (port->nport->pi_enable &&
!(cm_id->device->attrs.device_cap_flags &
IB_DEVICE_INTEGRITY_HANDOVER)) {
pr_err("T10-PI is not supported for %pISpcs\n", addr);
ret = -EINVAL;
goto out_destroy_id;
}
port->cm_id = cm_id;
return 0;
out_destroy_id:
rdma_destroy_id(cm_id);
return ret;
}
static void nvmet_rdma_repair_port_work(struct work_struct *w)
{
struct nvmet_rdma_port *port = container_of(to_delayed_work(w),
struct nvmet_rdma_port, repair_work);
int ret;
nvmet_rdma_disable_port(port);
ret = nvmet_rdma_enable_port(port);
if (ret)
schedule_delayed_work(&port->repair_work, 5 * HZ);
}
static int nvmet_rdma_add_port(struct nvmet_port *nport)
{
struct nvmet_rdma_port *port;
__kernel_sa_family_t af;
int ret;
port = kzalloc(sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
nport->priv = port;
port->nport = nport;
INIT_DELAYED_WORK(&port->repair_work, nvmet_rdma_repair_port_work);
switch (nport->disc_addr.adrfam) {
case NVMF_ADDR_FAMILY_IP4:
af = AF_INET;
break;
case NVMF_ADDR_FAMILY_IP6:
af = AF_INET6;
break;
default:
pr_err("address family %d not supported\n",
nport->disc_addr.adrfam);
ret = -EINVAL;
goto out_free_port;
}
if (nport->inline_data_size < 0) {
nport->inline_data_size = NVMET_RDMA_DEFAULT_INLINE_DATA_SIZE;
} else if (nport->inline_data_size > NVMET_RDMA_MAX_INLINE_DATA_SIZE) {
pr_warn("inline_data_size %u is too large, reducing to %u\n",
nport->inline_data_size,
NVMET_RDMA_MAX_INLINE_DATA_SIZE);
nport->inline_data_size = NVMET_RDMA_MAX_INLINE_DATA_SIZE;
}
ret = inet_pton_with_scope(&init_net, af, nport->disc_addr.traddr,
nport->disc_addr.trsvcid, &port->addr);
if (ret) {
pr_err("malformed ip/port passed: %s:%s\n",
nport->disc_addr.traddr, nport->disc_addr.trsvcid);
goto out_free_port;
}
ret = nvmet_rdma_enable_port(port);
if (ret)
goto out_free_port;
pr_info("enabling port %d (%pISpcs)\n",
le16_to_cpu(nport->disc_addr.portid),
(struct sockaddr *)&port->addr);
return 0;
out_free_port:
kfree(port);
return ret;
}
static void nvmet_rdma_remove_port(struct nvmet_port *nport)
{
struct nvmet_rdma_port *port = nport->priv;
cancel_delayed_work_sync(&port->repair_work);
nvmet_rdma_disable_port(port);
kfree(port);
}
static void nvmet_rdma_disc_port_addr(struct nvmet_req *req,
struct nvmet_port *nport, char *traddr)
{
struct nvmet_rdma_port *port = nport->priv;
struct rdma_cm_id *cm_id = port->cm_id;
if (inet_addr_is_any((struct sockaddr *)&cm_id->route.addr.src_addr)) {
struct nvmet_rdma_rsp *rsp =
container_of(req, struct nvmet_rdma_rsp, req);
struct rdma_cm_id *req_cm_id = rsp->queue->cm_id;
struct sockaddr *addr = (void *)&req_cm_id->route.addr.src_addr;
sprintf(traddr, "%pISc", addr);
} else {
memcpy(traddr, nport->disc_addr.traddr, NVMF_TRADDR_SIZE);
}
}
static u8 nvmet_rdma_get_mdts(const struct nvmet_ctrl *ctrl)
{
if (ctrl->pi_support)
return NVMET_RDMA_MAX_METADATA_MDTS;
return NVMET_RDMA_MAX_MDTS;
}
static const struct nvmet_fabrics_ops nvmet_rdma_ops = {
.owner = THIS_MODULE,
.type = NVMF_TRTYPE_RDMA,
.msdbd = 1,
.has_keyed_sgls = 1,
.metadata_support = 1,
.add_port = nvmet_rdma_add_port,
.remove_port = nvmet_rdma_remove_port,
.queue_response = nvmet_rdma_queue_response,
.delete_ctrl = nvmet_rdma_delete_ctrl,
.disc_traddr = nvmet_rdma_disc_port_addr,
.get_mdts = nvmet_rdma_get_mdts,
};
static void nvmet_rdma_remove_one(struct ib_device *ib_device, void *client_data)
{
struct nvmet_rdma_queue *queue, *tmp;
struct nvmet_rdma_device *ndev;
bool found = false;
mutex_lock(&device_list_mutex);
list_for_each_entry(ndev, &device_list, entry) {
if (ndev->device == ib_device) {
found = true;
break;
}
}
mutex_unlock(&device_list_mutex);
if (!found)
return;
/*
* IB Device that is used by nvmet controllers is being removed,
* delete all queues using this device.
*/
mutex_lock(&nvmet_rdma_queue_mutex);
list_for_each_entry_safe(queue, tmp, &nvmet_rdma_queue_list,
queue_list) {
if (queue->dev->device != ib_device)
continue;
pr_info("Removing queue %d\n", queue->idx);
list_del_init(&queue->queue_list);
__nvmet_rdma_queue_disconnect(queue);
}
mutex_unlock(&nvmet_rdma_queue_mutex);
flush_scheduled_work();
}
static struct ib_client nvmet_rdma_ib_client = {
.name = "nvmet_rdma",
.remove = nvmet_rdma_remove_one
};
static int __init nvmet_rdma_init(void)
{
int ret;
ret = ib_register_client(&nvmet_rdma_ib_client);
if (ret)
return ret;
ret = nvmet_register_transport(&nvmet_rdma_ops);
if (ret)
goto err_ib_client;
return 0;
err_ib_client:
ib_unregister_client(&nvmet_rdma_ib_client);
return ret;
}
static void __exit nvmet_rdma_exit(void)
{
nvmet_unregister_transport(&nvmet_rdma_ops);
ib_unregister_client(&nvmet_rdma_ib_client);
WARN_ON_ONCE(!list_empty(&nvmet_rdma_queue_list));
ida_destroy(&nvmet_rdma_queue_ida);
}
module_init(nvmet_rdma_init);
module_exit(nvmet_rdma_exit);
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("nvmet-transport-1"); /* 1 == NVMF_TRTYPE_RDMA */