diff options
| -rw-r--r-- | drivers/nvme/target/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/nvme/target/Makefile | 2 | ||||
| -rw-r--r-- | drivers/nvme/target/tcp.c | 1737 |
3 files changed, 1749 insertions, 0 deletions
diff --git a/drivers/nvme/target/Kconfig b/drivers/nvme/target/Kconfig index 3c7b61ddb0d1..d94f25cde019 100644 --- a/drivers/nvme/target/Kconfig +++ b/drivers/nvme/target/Kconfig @@ -60,3 +60,13 @@ config NVME_TARGET_FCLOOP to test NVMe-FC transport interfaces. If unsure, say N. + +config NVME_TARGET_TCP + tristate "NVMe over Fabrics TCP target support" + depends on INET + depends on NVME_TARGET + help + This enables the NVMe TCP target support, which allows exporting NVMe + devices over TCP. + + If unsure, say N. diff --git a/drivers/nvme/target/Makefile b/drivers/nvme/target/Makefile index 8118c93391c6..8c3ad0fb6860 100644 --- a/drivers/nvme/target/Makefile +++ b/drivers/nvme/target/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_NVME_TARGET_LOOP) += nvme-loop.o obj-$(CONFIG_NVME_TARGET_RDMA) += nvmet-rdma.o obj-$(CONFIG_NVME_TARGET_FC) += nvmet-fc.o obj-$(CONFIG_NVME_TARGET_FCLOOP) += nvme-fcloop.o +obj-$(CONFIG_NVME_TARGET_TCP) += nvmet-tcp.o nvmet-y += core.o configfs.o admin-cmd.o fabrics-cmd.o \ discovery.o io-cmd-file.o io-cmd-bdev.o @@ -12,3 +13,4 @@ nvme-loop-y += loop.o nvmet-rdma-y += rdma.o nvmet-fc-y += fc.o nvme-fcloop-y += fcloop.o +nvmet-tcp-y += tcp.o diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c new file mode 100644 index 000000000000..d31bec260160 --- /dev/null +++ b/drivers/nvme/target/tcp.c @@ -0,0 +1,1737 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVMe over Fabrics TCP target. + * Copyright (c) 2018 Lightbits Labs. All rights reserved. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/nvme-tcp.h> +#include <net/sock.h> +#include <net/tcp.h> +#include <linux/inet.h> +#include <linux/llist.h> +#include <crypto/hash.h> + +#include "nvmet.h" + +#define NVMET_TCP_DEF_INLINE_DATA_SIZE (4 * PAGE_SIZE) + +#define NVMET_TCP_RECV_BUDGET 8 +#define NVMET_TCP_SEND_BUDGET 8 +#define NVMET_TCP_IO_WORK_BUDGET 64 + +enum nvmet_tcp_send_state { + NVMET_TCP_SEND_DATA_PDU, + NVMET_TCP_SEND_DATA, + NVMET_TCP_SEND_R2T, + NVMET_TCP_SEND_DDGST, + NVMET_TCP_SEND_RESPONSE +}; + +enum nvmet_tcp_recv_state { + NVMET_TCP_RECV_PDU, + NVMET_TCP_RECV_DATA, + NVMET_TCP_RECV_DDGST, + NVMET_TCP_RECV_ERR, +}; + +enum { + NVMET_TCP_F_INIT_FAILED = (1 << 0), +}; + +struct nvmet_tcp_cmd { + struct nvmet_tcp_queue *queue; + struct nvmet_req req; + + struct nvme_tcp_cmd_pdu *cmd_pdu; + struct nvme_tcp_rsp_pdu *rsp_pdu; + struct nvme_tcp_data_pdu *data_pdu; + struct nvme_tcp_r2t_pdu *r2t_pdu; + + u32 rbytes_done; + u32 wbytes_done; + + u32 pdu_len; + u32 pdu_recv; + int sg_idx; + int nr_mapped; + struct msghdr recv_msg; + struct kvec *iov; + u32 flags; + + struct list_head entry; + struct llist_node lentry; + + /* send state */ + u32 offset; + struct scatterlist *cur_sg; + enum nvmet_tcp_send_state state; + + __le32 exp_ddgst; + __le32 recv_ddgst; +}; + +enum nvmet_tcp_queue_state { + NVMET_TCP_Q_CONNECTING, + NVMET_TCP_Q_LIVE, + NVMET_TCP_Q_DISCONNECTING, +}; + +struct nvmet_tcp_queue { + struct socket *sock; + struct nvmet_tcp_port *port; + struct work_struct io_work; + int cpu; + struct nvmet_cq nvme_cq; + struct nvmet_sq nvme_sq; + + /* send state */ + struct nvmet_tcp_cmd *cmds; + unsigned int nr_cmds; + struct list_head free_list; + struct llist_head resp_list; + struct list_head resp_send_list; + int send_list_len; + struct nvmet_tcp_cmd *snd_cmd; + + /* recv state */ + int offset; + int left; + enum nvmet_tcp_recv_state rcv_state; + struct nvmet_tcp_cmd *cmd; + union nvme_tcp_pdu pdu; + + /* digest state */ + bool hdr_digest; + bool data_digest; + struct ahash_request *snd_hash; + struct ahash_request *rcv_hash; + + spinlock_t state_lock; + enum nvmet_tcp_queue_state state; + + struct sockaddr_storage sockaddr; + struct sockaddr_storage sockaddr_peer; + struct work_struct release_work; + + int idx; + struct list_head queue_list; + + struct nvmet_tcp_cmd connect; + + struct page_frag_cache pf_cache; + + void (*data_ready)(struct sock *); + void (*state_change)(struct sock *); + void (*write_space)(struct sock *); +}; + +struct nvmet_tcp_port { + struct socket *sock; + struct work_struct accept_work; + struct nvmet_port *nport; + struct sockaddr_storage addr; + int last_cpu; + void (*data_ready)(struct sock *); +}; + +static DEFINE_IDA(nvmet_tcp_queue_ida); +static LIST_HEAD(nvmet_tcp_queue_list); +static DEFINE_MUTEX(nvmet_tcp_queue_mutex); + +static struct workqueue_struct *nvmet_tcp_wq; +static struct nvmet_fabrics_ops nvmet_tcp_ops; +static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c); +static void nvmet_tcp_finish_cmd(struct nvmet_tcp_cmd *cmd); + +static inline u16 nvmet_tcp_cmd_tag(struct nvmet_tcp_queue *queue, + struct nvmet_tcp_cmd *cmd) +{ + return cmd - queue->cmds; +} + +static inline bool nvmet_tcp_has_data_in(struct nvmet_tcp_cmd *cmd) +{ + return nvme_is_write(cmd->req.cmd) && + cmd->rbytes_done < cmd->req.transfer_len; +} + +static inline bool nvmet_tcp_need_data_in(struct nvmet_tcp_cmd *cmd) +{ + return nvmet_tcp_has_data_in(cmd) && !cmd->req.rsp->status; +} + +static inline bool nvmet_tcp_need_data_out(struct nvmet_tcp_cmd *cmd) +{ + return !nvme_is_write(cmd->req.cmd) && + cmd->req.transfer_len > 0 && + !cmd->req.rsp->status; +} + +static inline bool nvmet_tcp_has_inline_data(struct nvmet_tcp_cmd *cmd) +{ + return nvme_is_write(cmd->req.cmd) && cmd->pdu_len && + !cmd->rbytes_done; +} + +static inline struct nvmet_tcp_cmd * +nvmet_tcp_get_cmd(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmd; + + cmd = list_first_entry_or_null(&queue->free_list, + struct nvmet_tcp_cmd, entry); + if (!cmd) + return NULL; + list_del_init(&cmd->entry); + + cmd->rbytes_done = cmd->wbytes_done = 0; + cmd->pdu_len = 0; + cmd->pdu_recv = 0; + cmd->iov = NULL; + cmd->flags = 0; + return cmd; +} + +static inline void nvmet_tcp_put_cmd(struct nvmet_tcp_cmd *cmd) +{ + if (unlikely(cmd == &cmd->queue->connect)) + return; + + list_add_tail(&cmd->entry, &cmd->queue->free_list); +} + +static inline u8 nvmet_tcp_hdgst_len(struct nvmet_tcp_queue *queue) +{ + return queue->hdr_digest ? NVME_TCP_DIGEST_LENGTH : 0; +} + +static inline u8 nvmet_tcp_ddgst_len(struct nvmet_tcp_queue *queue) +{ + return queue->data_digest ? NVME_TCP_DIGEST_LENGTH : 0; +} + +static inline void nvmet_tcp_hdgst(struct ahash_request *hash, + void *pdu, size_t len) +{ + struct scatterlist sg; + + sg_init_one(&sg, pdu, len); + ahash_request_set_crypt(hash, &sg, pdu + len, len); + crypto_ahash_digest(hash); +} + +static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue, + void *pdu, size_t len) +{ + struct nvme_tcp_hdr *hdr = pdu; + __le32 recv_digest; + __le32 exp_digest; + + if (unlikely(!(hdr->flags & NVME_TCP_F_HDGST))) { + pr_err("queue %d: header digest enabled but no header digest\n", + queue->idx); + return -EPROTO; + } + + recv_digest = *(__le32 *)(pdu + hdr->hlen); + nvmet_tcp_hdgst(queue->rcv_hash, pdu, len); + exp_digest = *(__le32 *)(pdu + hdr->hlen); + if (recv_digest != exp_digest) { + pr_err("queue %d: header digest error: recv %#x expected %#x\n", + queue->idx, le32_to_cpu(recv_digest), + le32_to_cpu(exp_digest)); + return -EPROTO; + } + + return 0; +} + +static int nvmet_tcp_check_ddgst(struct nvmet_tcp_queue *queue, void *pdu) +{ + struct nvme_tcp_hdr *hdr = pdu; + u8 digest_len = nvmet_tcp_hdgst_len(queue); + u32 len; + + len = le32_to_cpu(hdr->plen) - hdr->hlen - + (hdr->flags & NVME_TCP_F_HDGST ? digest_len : 0); + + if (unlikely(len && !(hdr->flags & NVME_TCP_F_DDGST))) { + pr_err("queue %d: data digest flag is cleared\n", queue->idx); + return -EPROTO; + } + + return 0; +} + +static void nvmet_tcp_unmap_pdu_iovec(struct nvmet_tcp_cmd *cmd) +{ + struct scatterlist *sg; + int i; + + sg = &cmd->req.sg[cmd->sg_idx]; + + for (i = 0; i < cmd->nr_mapped; i++) + kunmap(sg_page(&sg[i])); +} + +static void nvmet_tcp_map_pdu_iovec(struct nvmet_tcp_cmd *cmd) +{ + struct kvec *iov = cmd->iov; + struct scatterlist *sg; + u32 length, offset, sg_offset; + + length = cmd->pdu_len; + cmd->nr_mapped = DIV_ROUND_UP(length, PAGE_SIZE); + offset = cmd->rbytes_done; + cmd->sg_idx = DIV_ROUND_UP(offset, PAGE_SIZE); + sg_offset = offset % PAGE_SIZE; + sg = &cmd->req.sg[cmd->sg_idx]; + + while (length) { + u32 iov_len = min_t(u32, length, sg->length - sg_offset); + + iov->iov_base = kmap(sg_page(sg)) + sg->offset + sg_offset; + iov->iov_len = iov_len; + + length -= iov_len; + sg = sg_next(sg); + iov++; + } + + iov_iter_kvec(&cmd->recv_msg.msg_iter, READ, cmd->iov, + cmd->nr_mapped, cmd->pdu_len); +} + +static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue) +{ + queue->rcv_state = NVMET_TCP_RECV_ERR; + if (queue->nvme_sq.ctrl) + nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl); + else + kernel_sock_shutdown(queue->sock, SHUT_RDWR); +} + +static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd) +{ + struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl; + u32 len = le32_to_cpu(sgl->length); + + if (!cmd->req.data_len) + return 0; + + if (sgl->type == ((NVME_SGL_FMT_DATA_DESC << 4) | + NVME_SGL_FMT_OFFSET)) { + if (!nvme_is_write(cmd->req.cmd)) + return NVME_SC_INVALID_FIELD | NVME_SC_DNR; + + if (len > cmd->req.port->inline_data_size) + return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR; + cmd->pdu_len = len; + } + cmd->req.transfer_len += len; + + cmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt); + if (!cmd->req.sg) + return NVME_SC_INTERNAL; + cmd->cur_sg = cmd->req.sg; + + if (nvmet_tcp_has_data_in(cmd)) { + cmd->iov = kmalloc_array(cmd->req.sg_cnt, + sizeof(*cmd->iov), GFP_KERNEL); + if (!cmd->iov) + goto err; + } + + return 0; +err: + sgl_free(cmd->req.sg); + return NVME_SC_INTERNAL; +} + +static void nvmet_tcp_ddgst(struct ahash_request *hash, + struct nvmet_tcp_cmd *cmd) +{ + ahash_request_set_crypt(hash, cmd->req.sg, + (void *)&cmd->exp_ddgst, cmd->req.transfer_len); + crypto_ahash_digest(hash); +} + +static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd) +{ + struct nvme_tcp_data_pdu *pdu = cmd->data_pdu; + struct nvmet_tcp_queue *queue = cmd->queue; + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + u8 ddgst = nvmet_tcp_ddgst_len(cmd->queue); + + cmd->offset = 0; + cmd->state = NVMET_TCP_SEND_DATA_PDU; + + pdu->hdr.type = nvme_tcp_c2h_data; + pdu->hdr.flags = NVME_TCP_F_DATA_LAST; + pdu->hdr.hlen = sizeof(*pdu); + pdu->hdr.pdo = pdu->hdr.hlen + hdgst; + pdu->hdr.plen = + cpu_to_le32(pdu->hdr.hlen + hdgst + + cmd->req.transfer_len + ddgst); + pdu->command_id = cmd->req.rsp->command_id; + pdu->data_length = cpu_to_le32(cmd->req.transfer_len); + pdu->data_offset = cpu_to_le32(cmd->wbytes_done); + + if (queue->data_digest) { + pdu->hdr.flags |= NVME_TCP_F_DDGST; + nvmet_tcp_ddgst(queue->snd_hash, cmd); + } + + if (cmd->queue->hdr_digest) { + pdu->hdr.flags |= NVME_TCP_F_HDGST; + nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + } +} + +static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd) +{ + struct nvme_tcp_r2t_pdu *pdu = cmd->r2t_pdu; + struct nvmet_tcp_queue *queue = cmd->queue; + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + + cmd->offset = 0; + cmd->state = NVMET_TCP_SEND_R2T; + + pdu->hdr.type = nvme_tcp_r2t; + pdu->hdr.flags = 0; + pdu->hdr.hlen = sizeof(*pdu); + pdu->hdr.pdo = 0; + pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst); + + pdu->command_id = cmd->req.cmd->common.command_id; + pdu->ttag = nvmet_tcp_cmd_tag(cmd->queue, cmd); + pdu->r2t_length = cpu_to_le32(cmd->req.transfer_len - cmd->rbytes_done); + pdu->r2t_offset = cpu_to_le32(cmd->rbytes_done); + if (cmd->queue->hdr_digest) { + pdu->hdr.flags |= NVME_TCP_F_HDGST; + nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + } +} + +static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd) +{ + struct nvme_tcp_rsp_pdu *pdu = cmd->rsp_pdu; + struct nvmet_tcp_queue *queue = cmd->queue; + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + + cmd->offset = 0; + cmd->state = NVMET_TCP_SEND_RESPONSE; + + pdu->hdr.type = nvme_tcp_rsp; + pdu->hdr.flags = 0; + pdu->hdr.hlen = sizeof(*pdu); + pdu->hdr.pdo = 0; + pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst); + if (cmd->queue->hdr_digest) { + pdu->hdr.flags |= NVME_TCP_F_HDGST; + nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); + } +} + +static void nvmet_tcp_process_resp_list(struct nvmet_tcp_queue *queue) +{ + struct llist_node *node; + + node = llist_del_all(&queue->resp_list); + if (!node) + return; + + while (node) { + struct nvmet_tcp_cmd *cmd = llist_entry(node, + struct nvmet_tcp_cmd, lentry); + + list_add(&cmd->entry, &queue->resp_send_list); + node = node->next; + queue->send_list_len++; + } +} + +static struct nvmet_tcp_cmd *nvmet_tcp_fetch_cmd(struct nvmet_tcp_queue *queue) +{ + queue->snd_cmd = list_first_entry_or_null(&queue->resp_send_list, + struct nvmet_tcp_cmd, entry); + if (!queue->snd_cmd) { + nvmet_tcp_process_resp_list(queue); + queue->snd_cmd = + list_first_entry_or_null(&queue->resp_send_list, + struct nvmet_tcp_cmd, entry); + if (unlikely(!queue->snd_cmd)) + return NULL; + } + + list_del_init(&queue->snd_cmd->entry); + queue->send_list_len--; + + if (nvmet_tcp_need_data_out(queue->snd_cmd)) + nvmet_setup_c2h_data_pdu(queue->snd_cmd); + else if (nvmet_tcp_need_data_in(queue->snd_cmd)) + nvmet_setup_r2t_pdu(queue->snd_cmd); + else + nvmet_setup_response_pdu(queue->snd_cmd); + + return queue->snd_cmd; +} + +static void nvmet_tcp_queue_response(struct nvmet_req *req) +{ + struct nvmet_tcp_cmd *cmd = + container_of(req, struct nvmet_tcp_cmd, req); + struct nvmet_tcp_queue *queue = cmd->queue; + + llist_add(&cmd->lentry, &queue->resp_list); + queue_work_on(cmd->queue->cpu, nvmet_tcp_wq, &cmd->queue->io_work); +} + +static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd) +{ + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + int left = sizeof(*cmd->data_pdu) - cmd->offset + hdgst; + int ret; + + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu), + offset_in_page(cmd->data_pdu) + cmd->offset, + left, MSG_DONTWAIT | MSG_MORE); + if (ret <= 0) + return ret; + + cmd->offset += ret; + left -= ret; + + if (left) + return -EAGAIN; + + cmd->state = NVMET_TCP_SEND_DATA; + cmd->offset = 0; + return 1; +} + +static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd) +{ + struct nvmet_tcp_queue *queue = cmd->queue; + int ret; + + while (cmd->cur_sg) { + struct page *page = sg_page(cmd->cur_sg); + u32 left = cmd->cur_sg->length - cmd->offset; + + ret = kernel_sendpage(cmd->queue->sock, page, cmd->offset, + left, MSG_DONTWAIT | MSG_MORE); + if (ret <= 0) + return ret; + + cmd->offset += ret; + cmd->wbytes_done += ret; + + /* Done with sg?*/ + if (cmd->offset == cmd->cur_sg->length) { + cmd->cur_sg = sg_next(cmd->cur_sg); + cmd->offset = 0; + } + } + + if (queue->data_digest) { + cmd->state = NVMET_TCP_SEND_DDGST; + cmd->offset = 0; + } else { + nvmet_setup_response_pdu(cmd); + } + return 1; + +} + +static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd, + bool last_in_batch) +{ + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + int left = sizeof(*cmd->rsp_pdu) - cmd->offset + hdgst; + int flags = MSG_DONTWAIT; + int ret; + + if (!last_in_batch && cmd->queue->send_list_len) + flags |= MSG_MORE; + else + flags |= MSG_EOR; + + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu), + offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags); + if (ret <= 0) + return ret; + cmd->offset += ret; + left -= ret; + + if (left) + return -EAGAIN; + + kfree(cmd->iov); + sgl_free(cmd->req.sg); + cmd->queue->snd_cmd = NULL; + nvmet_tcp_put_cmd(cmd); + return 1; +} + +static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batch) +{ + u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); + int left = sizeof(*cmd->r2t_pdu) - cmd->offset + hdgst; + int flags = MSG_DONTWAIT; + int ret; + + if (!last_in_batch && cmd->queue->send_list_len) + flags |= MSG_MORE; + else + flags |= MSG_EOR; + + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu), + offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags); + if (ret <= 0) + return ret; + cmd->offset += ret; + left -= ret; + + if (left) + return -EAGAIN; + + cmd->queue->snd_cmd = NULL; + return 1; +} + +static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd) +{ + struct nvmet_tcp_queue *queue = cmd->queue; + struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; + struct kvec iov = { + .iov_base = &cmd->exp_ddgst + cmd->offset, + .iov_len = NVME_TCP_DIGEST_LENGTH - cmd->offset + }; + int ret; + + ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len); + if (unlikely(ret <= 0)) + return ret; + + cmd->offset += ret; + nvmet_setup_response_pdu(cmd); + return 1; +} + +static int nvmet_tcp_try_send_one(struct nvmet_tcp_queue *queue, + bool last_in_batch) +{ + struct nvmet_tcp_cmd *cmd = queue->snd_cmd; + int ret = 0; + + if (!cmd || queue->state == NVMET_TCP_Q_DISCONNECTING) { + cmd = nvmet_tcp_fetch_cmd(queue); + if (unlikely(!cmd)) + return 0; + } + + if (cmd->state == NVMET_TCP_SEND_DATA_PDU) { + ret = nvmet_try_send_data_pdu(cmd); + if (ret <= 0) + goto done_send; + } + + if (cmd->state == NVMET_TCP_SEND_DATA) { + ret = nvmet_try_send_data(cmd); + if (ret <= 0) + goto done_send; + } + + if (cmd->state == NVMET_TCP_SEND_DDGST) { + ret = nvmet_try_send_ddgst(cmd); + if (ret <= 0) + goto done_send; + } + + if (cmd->state == NVMET_TCP_SEND_R2T) { + ret = nvmet_try_send_r2t(cmd, last_in_batch); + if (ret <= 0) + goto done_send; + } + + if (cmd->state == NVMET_TCP_SEND_RESPONSE) + ret = nvmet_try_send_response(cmd, last_in_batch); + +done_send: + if (ret < 0) { + if (ret == -EAGAIN) + return 0; + return ret; + } + + return 1; +} + +static int nvmet_tcp_try_send(struct nvmet_tcp_queue *queue, + int budget, int *sends) +{ + int i, ret = 0; + + for (i = 0; i < budget; i++) { + ret = nvmet_tcp_try_send_one(queue, i == budget - 1); + if (ret <= 0) + break; + (*sends)++; + } + + return ret; +} + +static void nvmet_prepare_receive_pdu(struct nvmet_tcp_queue *queue) +{ + queue->offset = 0; + queue->left = sizeof(struct nvme_tcp_hdr); + queue->cmd = NULL; + queue->rcv_state = NVMET_TCP_RECV_PDU; +} + +static void nvmet_tcp_free_crypto(struct nvmet_tcp_queue *queue) +{ + struct crypto_ahash *tfm = crypto_ahash_reqtfm(queue->rcv_hash); + + ahash_request_free(queue->rcv_hash); + ahash_request_free(queue->snd_hash); + crypto_free_ahash(tfm); +} + +static int nvmet_tcp_alloc_crypto(struct nvmet_tcp_queue *queue) +{ + struct crypto_ahash *tfm; + + tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + queue->snd_hash = ahash_request_alloc(tfm, GFP_KERNEL); + if (!queue->snd_hash) + goto free_tfm; + ahash_request_set_callback(queue->snd_hash, 0, NULL, NULL); + + queue->rcv_hash = ahash_request_alloc(tfm, GFP_KERNEL); + if (!queue->rcv_hash) + goto free_snd_hash; + ahash_request_set_callback(queue->rcv_hash, 0, NULL, NULL); + + return 0; +free_snd_hash: + ahash_request_free(queue->snd_hash); +free_tfm: + crypto_free_ahash(tfm); + return -ENOMEM; +} + + +static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) +{ + struct nvme_tcp_icreq_pdu *icreq = &queue->pdu.icreq; + struct nvme_tcp_icresp_pdu *icresp = &queue->pdu.icresp; + struct msghdr msg = {}; + struct kvec iov; + int ret; + + if (le32_to_cpu(icreq->hdr.plen) != sizeof(struct nvme_tcp_icreq_pdu)) { + pr_err("bad nvme-tcp pdu length (%d)\n", + le32_to_cpu(icreq->hdr.plen)); + nvmet_tcp_fatal_error(queue); + } + + if (icreq->pfv != NVME_TCP_PFV_1_0) { + pr_err("queue %d: bad pfv %d\n", queue->idx, icreq->pfv); + return -EPROTO; + } + + if (icreq->hpda != 0) { + pr_err("queue %d: unsupported hpda %d\n", queue->idx, + icreq->hpda); + return -EPROTO; + } + + if (icreq->maxr2t != 0) { + pr_err("queue %d: unsupported maxr2t %d\n", queue->idx, + le16_to_cpu(icreq->maxr2t) + 1); + return -EPROTO; + } + + queue->hdr_digest = !!(icreq->digest & NVME_TCP_HDR_DIGEST_ENABLE); + queue->data_digest = !!(icreq->digest & NVME_TCP_DATA_DIGEST_ENABLE); + if (queue->hdr_digest || queue->data_digest) { + ret = nvmet_tcp_alloc_crypto(queue); + if (ret) + return ret; + } + + memset(icresp, 0, sizeof(*icresp)); + icresp->hdr.type = nvme_tcp_icresp; + icresp->hdr.hlen = sizeof(*icresp); + icresp->hdr.pdo = 0; + icresp->hdr.plen = cpu_to_le32(icresp->hdr.hlen); + icresp->pfv = cpu_to_le16(NVME_TCP_PFV_1_0); + icresp->maxdata = 0xffff; /* FIXME: support r2t */ + icresp->cpda = 0; + if (queue->hdr_digest) + icresp->digest |= NVME_TCP_HDR_DIGEST_ENABLE; + if (queue->data_digest) + icresp->digest |= NVME_TCP_DATA_DIGEST_ENABLE; + + iov.iov_base = icresp; + iov.iov_len = sizeof(*icresp); + ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len); + if (ret < 0) + goto free_crypto; + + queue->state = NVMET_TCP_Q_LIVE; + nvmet_prepare_receive_pdu(queue); + return 0; +free_crypto: + if (queue->hdr_digest || queue->data_digest) + nvmet_tcp_free_crypto(queue); + return ret; +} + +static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, + struct nvmet_tcp_cmd *cmd, struct nvmet_req *req) +{ + int ret; + + /* recover the expected data transfer length */ + req->data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length); + + if (!nvme_is_write(cmd->req.cmd) || + req->data_len > cmd->req.port->inline_data_size) { + nvmet_prepare_receive_pdu(queue); + return; + } + + ret = nvmet_tcp_map_data(cmd); + if (unlikely(ret)) { + pr_err("queue %d: failed to map data\n", queue->idx); + nvmet_tcp_fatal_error(queue); + return; + } + + queue->rcv_state = NVMET_TCP_RECV_DATA; + nvmet_tcp_map_pdu_iovec(cmd); + cmd->flags |= NVMET_TCP_F_INIT_FAILED; +} + +static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) +{ + struct nvme_tcp_data_pdu *data = &queue->pdu.data; + struct nvmet_tcp_cmd *cmd; + + cmd = &queue->cmds[data->ttag]; + + if (le32_to_cpu(data->data_offset) != cmd->rbytes_done) { + pr_err("ttag %u unexpected data offset %u (expected %u)\n", + data->ttag, le32_to_cpu(data->data_offset), + cmd->rbytes_done); + /* FIXME: use path and transport errors */ + nvmet_req_complete(&cmd->req, + NVME_SC_INVALID_FIELD | NVME_SC_DNR); + return -EPROTO; + } + + cmd->pdu_len = le32_to_cpu(data->data_length); + cmd->pdu_recv = 0; + nvmet_tcp_map_pdu_iovec(cmd); + queue->cmd = cmd; + queue->rcv_state = NVMET_TCP_RECV_DATA; + + return 0; +} + +static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) +{ + struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr; + struct nvme_command *nvme_cmd = &queue->pdu.cmd.cmd; + struct nvmet_req *req; + int ret; + + if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) { + if (hdr->type != nvme_tcp_icreq) { + pr_err("unexpected pdu type (%d) before icreq\n", + hdr->type); + nvmet_tcp_fatal_error(queue); + return -EPROTO; + } + return nvmet_tcp_handle_icreq(queue); + } + + if (hdr->type == nvme_tcp_h2c_data) { + ret = nvmet_tcp_handle_h2c_data_pdu(queue); + if (unlikely(ret)) + return ret; + return 0; + } + + queue->cmd = nvmet_tcp_get_cmd(queue); + if (unlikely(!queue->cmd)) { + /* This should never happen */ + pr_err("queue %d: out of commands (%d) send_list_len: %d, opcode: %d", + queue->idx, queue->nr_cmds, queue->send_list_len, + nvme_cmd->common.opcode); + nvmet_tcp_fatal_error(queue); + return -ENOMEM; + } + + req = &queue->cmd->req; + memcpy(req->cmd, nvme_cmd, sizeof(*nvme_cmd)); + + if (unlikely(!nvmet_req_init(req, &queue->nvme_cq, + &queue->nvme_sq, &nvmet_tcp_ops))) { + pr_err("failed cmd %p id %d opcode %d, data_len: %d\n", + req->cmd, req->cmd->common.command_id, + req->cmd->common.opcode, + le32_to_cpu(req->cmd->common.dptr.sgl.length)); + + nvmet_tcp_handle_req_failure(queue, queue->cmd, req); + return -EAGAIN; + } + + ret = nvmet_tcp_map_data(queue->cmd); + if (unlikely(ret)) { + pr_err("queue %d: failed to map data\n", queue->idx); + if (nvmet_tcp_has_inline_data(queue->cmd)) + nvmet_tcp_fatal_error(queue); + else + nvmet_req_complete(req, ret); + ret = -EAGAIN; + goto out; + } + + if (nvmet_tcp_need_data_in(queue->cmd)) { + if (nvmet_tcp_has_inline_data(queue->cmd)) { + queue->rcv_state = NVMET_TCP_RECV_DATA; + nvmet_tcp_map_pdu_iovec(queue->cmd); + return 0; + } + /* send back R2T */ + nvmet_tcp_queue_response(&queue->cmd->req); + goto out; + } + + nvmet_req_execute(&queue->cmd->req); +out: + nvmet_prepare_receive_pdu(queue); + return ret; +} + +static const u8 nvme_tcp_pdu_sizes[] = { + [nvme_tcp_icreq] = sizeof(struct nvme_tcp_icreq_pdu), + [nvme_tcp_cmd] = sizeof(struct nvme_tcp_cmd_pdu), + [nvme_tcp_h2c_data] = sizeof(struct nvme_tcp_data_pdu), +}; + +static inline u8 nvmet_tcp_pdu_size(u8 type) +{ + size_t idx = type; + + return (idx < ARRAY_SIZE(nvme_tcp_pdu_sizes) && + nvme_tcp_pdu_sizes[idx]) ? + nvme_tcp_pdu_sizes[idx] : 0; +} + +static inline bool nvmet_tcp_pdu_valid(u8 type) +{ + switch (type) { + case nvme_tcp_icreq: + case nvme_tcp_cmd: + case nvme_tcp_h2c_data: + /* fallthru */ + return true; + } + + return false; +} + +static int nvmet_tcp_try_recv_pdu(struct nvmet_tcp_queue *queue) +{ + struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr; + int len; + struct kvec iov; + struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; + +recv: + iov.iov_base = (void *)&queue->pdu + queue->offset; + iov.iov_len = queue->left; + len = kernel_recvmsg(queue->sock, &msg, &iov, 1, + iov.iov_len, msg.msg_flags); + if (unlikely(len < 0)) + return len; + + queue->offset += len; + queue->left -= len; + if (queue->left) + return -EAGAIN; + + if (queue->offset == sizeof(struct nvme_tcp_hdr)) { + u8 hdgst = nvmet_tcp_hdgst_len(queue); + + if (unlikely(!nvmet_tcp_pdu_valid(hdr->type))) { + pr_err("unexpected pdu type %d\n", hdr->type); + nvmet_tcp_fatal_error(queue); + return -EIO; + } + + if (unlikely(hdr->hlen != nvmet_tcp_pdu_size(hdr->type))) { + pr_err("pdu %d bad hlen %d\n", hdr->type, hdr->hlen); + return -EIO; + } + + queue->left = hdr->hlen - queue->offset + hdgst; + goto recv; + } + + if (queue->hdr_digest && + nvmet_tcp_verify_hdgst(queue, &queue->pdu, queue->offset)) { + nvmet_tcp_fatal_error(queue); /* fatal */ + return -EPROTO; + } + + if (queue->data_digest && + nvmet_tcp_check_ddgst(queue, &queue->pdu)) { + nvmet_tcp_fatal_error(queue); /* fatal */ + return -EPROTO; + } + + return nvmet_tcp_done_recv_pdu(queue); +} + +static void nvmet_tcp_prep_recv_ddgst(struct nvmet_tcp_cmd *cmd) +{ + struct nvmet_tcp_queue *queue = cmd->queue; + + nvmet_tcp_ddgst(queue->rcv_hash, cmd); + queue->offset = 0; + queue->left = NVME_TCP_DIGEST_LENGTH; + queue->rcv_state = NVMET_TCP_RECV_DDGST; +} + +static int nvmet_tcp_try_recv_data(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmd = queue->cmd; + int ret; + + while (msg_data_left(&cmd->recv_msg)) { + ret = sock_recvmsg(cmd->queue->sock, &cmd->recv_msg, + cmd->recv_msg.msg_flags); + if (ret <= 0) + return ret; + + cmd->pdu_recv += ret; + cmd->rbytes_done += ret; + } + + nvmet_tcp_unmap_pdu_iovec(cmd); + + if (!(cmd->flags & NVMET_TCP_F_INIT_FAILED) && + cmd->rbytes_done == cmd->req.transfer_len) { + if (queue->data_digest) { + nvmet_tcp_prep_recv_ddgst(cmd); + return 0; + } + nvmet_req_execute(&cmd->req); + } + + nvmet_prepare_receive_pdu(queue); + return 0; +} + +static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmd = queue->cmd; + int ret; + struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; + struct kvec iov = { + .iov_base = (void *)&cmd->recv_ddgst + queue->offset, + .iov_len = queue->left + }; + + ret = kernel_recvmsg(queue->sock, &msg, &iov, 1, + iov.iov_len, msg.msg_flags); + if (unlikely(ret < 0)) + return ret; + + queue->offset += ret; + queue->left -= ret; + if (queue->left) + return -EAGAIN; + + if (queue->data_digest && cmd->exp_ddgst != cmd->recv_ddgst) { + pr_err("queue %d: cmd %d pdu (%d) data digest error: recv %#x expected %#x\n", + queue->idx, cmd->req.cmd->common.command_id, + queue->pdu.cmd.hdr.type, le32_to_cpu(cmd->recv_ddgst), + le32_to_cpu(cmd->exp_ddgst)); + nvmet_tcp_finish_cmd(cmd); + nvmet_tcp_fatal_error(queue); + ret = -EPROTO; + goto out; + } + + if (!(cmd->flags & NVMET_TCP_F_INIT_FAILED) && + cmd->rbytes_done == cmd->req.transfer_len) + nvmet_req_execute(&cmd->req); + ret = 0; +out: + nvmet_prepare_receive_pdu(queue); + return ret; +} + +static int nvmet_tcp_try_recv_one(struct nvmet_tcp_queue *queue) +{ + int result; + + if (unlikely(queue->rcv_state == NVMET_TCP_RECV_ERR)) + return 0; + + if (queue->rcv_state == NVMET_TCP_RECV_PDU) { + result = nvmet_tcp_try_recv_pdu(queue); + if (result != 0) + goto done_recv; + } + + if (queue->rcv_state == NVMET_TCP_RECV_DATA) { + result = nvmet_tcp_try_recv_data(queue); + if (result != 0) + goto done_recv; + } + + if (queue->rcv_state == NVMET_TCP_RECV_DDGST) { + result = nvmet_tcp_try_recv_ddgst(queue); + if (result != 0) + goto done_recv; + } + +done_recv: + if (result < 0) { + if (result == -EAGAIN) + return 0; + return result; + } + return 1; +} + +static int nvmet_tcp_try_recv(struct nvmet_tcp_queue *queue, + int budget, int *recvs) +{ + int i, ret = 0; + + for (i = 0; i < budget; i++) { + ret = nvmet_tcp_try_recv_one(queue); + if (ret <= 0) + break; + (*recvs)++; + } + + return ret; +} + +static void nvmet_tcp_schedule_release_queue(struct nvmet_tcp_queue *queue) +{ + spin_lock(&queue->state_lock); + if (queue->state != NVMET_TCP_Q_DISCONNECTING) { + queue->state = NVMET_TCP_Q_DISCONNECTING; + schedule_work(&queue->release_work); + } + spin_unlock(&queue->state_lock); +} + +static void nvmet_tcp_io_work(struct work_struct *w) +{ + struct nvmet_tcp_queue *queue = + container_of(w, struct nvmet_tcp_queue, io_work); + bool pending; + int ret, ops = 0; + + do { + pending = false; + + ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops); + if (ret > 0) { + pending = true; + } else if (ret < 0) { + if (ret == -EPIPE || ret == -ECONNRESET) + kernel_sock_shutdown(queue->sock, SHUT_RDWR); + else + nvmet_tcp_fatal_error(queue); + return; + } + + ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops); + if (ret > 0) { + /* transmitted message/data */ + pending = true; + } else if (ret < 0) { + if (ret == -EPIPE || ret == -ECONNRESET) + kernel_sock_shutdown(queue->sock, SHUT_RDWR); + else + nvmet_tcp_fatal_error(queue); + return; + } + + } while (pending && ops < NVMET_TCP_IO_WORK_BUDGET); + + /* + * We exahusted our budget, requeue our selves + */ + if (pending) + queue_work_on(queue->cpu, nvmet_tcp_wq, &queue->io_work); +} + +static int nvmet_tcp_alloc_cmd(struct nvmet_tcp_queue *queue, + struct nvmet_tcp_cmd *c) +{ + u8 hdgst = nvmet_tcp_hdgst_len(queue); + + c->queue = queue; + c->req.port = queue->port->nport; + + c->cmd_pdu = page_frag_alloc(&queue->pf_cache, + sizeof(*c->cmd_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); + if (!c->cmd_pdu) + return -ENOMEM; + c->req.cmd = &c->cmd_pdu->cmd; + + c->rsp_pdu = page_frag_alloc(&queue->pf_cache, + sizeof(*c->rsp_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); + if (!c->rsp_pdu) + goto out_free_cmd; + c->req.rsp = &c->rsp_pdu->cqe; + + c->data_pdu = page_frag_alloc(&queue->pf_cache, + sizeof(*c->data_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); + if (!c->data_pdu) + goto out_free_rsp; + + c->r2t_pdu = page_frag_alloc(&queue->pf_cache, + sizeof(*c->r2t_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); + if (!c->r2t_pdu) + goto out_free_data; + + c->recv_msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; + + list_add_tail(&c->entry, &queue->free_list); + + return 0; +out_free_data: + page_frag_free(c->data_pdu); +out_free_rsp: + page_frag_free(c->rsp_pdu); +out_free_cmd: + page_frag_free(c->cmd_pdu); + return -ENOMEM; +} + +static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c) +{ + page_frag_free(c->r2t_pdu); + page_frag_free(c->data_pdu); + page_frag_free(c->rsp_pdu); + page_frag_free(c->cmd_pdu); +} + +static int nvmet_tcp_alloc_cmds(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmds; + int i, ret = -EINVAL, nr_cmds = queue->nr_cmds; + + cmds = kcalloc(nr_cmds, sizeof(struct nvmet_tcp_cmd), GFP_KERNEL); + if (!cmds) + goto out; + + for (i = 0; i < nr_cmds; i++) { + ret = nvmet_tcp_alloc_cmd(queue, cmds + i); + if (ret) + goto out_free; + } + + queue->cmds = cmds; + + return 0; +out_free: + while (--i >= 0) + nvmet_tcp_free_cmd(cmds + i); + kfree(cmds); +out: + return ret; +} + +static void nvmet_tcp_free_cmds(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmds = queue->cmds; + int i; + + for (i = 0; i < queue->nr_cmds; i++) + nvmet_tcp_free_cmd(cmds + i); + + nvmet_tcp_free_cmd(&queue->connect); + kfree(cmds); +} + +static void nvmet_tcp_restore_socket_callbacks(struct nvmet_tcp_queue *queue) +{ + struct socket *sock = queue->sock; + + write_lock_bh(&sock->sk->sk_callback_lock); + sock->sk->sk_data_ready = queue->data_ready; + sock->sk->sk_state_change = queue->state_change; + sock->sk->sk_write_space = queue->write_space; + sock->sk->sk_user_data = NULL; + write_unlock_bh(&sock->sk->sk_callback_lock); +} + +static void nvmet_tcp_finish_cmd(struct nvmet_tcp_cmd *cmd) +{ + nvmet_req_uninit(&cmd->req); + nvmet_tcp_unmap_pdu_iovec(cmd); + sgl_free(cmd->req.sg); +} + +static void nvmet_tcp_uninit_data_in_cmds(struct nvmet_tcp_queue *queue) +{ + struct nvmet_tcp_cmd *cmd = queue->cmds; + int i; + + for (i = 0; i < queue->nr_cmds; i++, cmd++) { + if (nvmet_tcp_need_data_in(cmd)) + nvmet_tcp_finish_cmd(cmd); + } + + if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect)) { + /* failed in connect */ + nvmet_tcp_finish_cmd(&queue->connect); + } +} + +static void nvmet_tcp_release_queue_work(struct work_struct *w) +{ + struct nvmet_tcp_queue *queue = + container_of(w, struct nvmet_tcp_queue, release_work); + + mutex_lock(&nvmet_tcp_queue_mutex); + list_del_init(&queue->queue_list); + mutex_unlock(&nvmet_tcp_queue_mutex); + + nvmet_tcp_restore_socket_callbacks(queue); + flush_work(&queue->io_work); + + nvmet_tcp_uninit_data_in_cmds(queue); + nvmet_sq_destroy(&queue->nvme_sq); + cancel_work_sync(&queue->io_work); + sock_release(queue->sock); + nvmet_tcp_free_cmds(queue); + if (queue->hdr_digest || queue->data_digest) + nvmet_tcp_free_crypto(queue); + ida_simple_remove(&nvmet_tcp_queue_ida, queue->idx); + + kfree(queue); +} + +static void nvmet_tcp_data_ready(struct sock *sk) +{ + struct nvmet_tcp_queue *queue; + + read_lock_bh(&sk->sk_callback_lock); + queue = sk->sk_user_data; + if (likely(queue)) + queue_work_on(queue->cpu, nvmet_tcp_wq, &queue->io_work); + read_unlock_bh(&sk->sk_callback_lock); +} + +static void nvmet_tcp_write_space(struct sock *sk) +{ + struct nvmet_tcp_queue *queue; + + read_lock_bh(&sk->sk_callback_lock); + queue = sk->sk_user_data; + if (unlikely(!queue)) + goto out; + + if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) { + queue->write_space(sk); + goto out; + } + + if (sk_stream_is_writeable(sk)) { + clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + queue_work_on(queue->cpu, nvmet_tcp_wq, &queue->io_work); + } +out: + read_unlock_bh(&sk->sk_callback_lock); +} + +static void nvmet_tcp_state_change(struct sock *sk) +{ + struct nvmet_tcp_queue *queue; + + write_lock_bh(&sk->sk_callback_lock); + queue = sk->sk_user_data; + if (!queue) + goto done; + + switch (sk->sk_state) { + case TCP_FIN_WAIT1: + case TCP_CLOSE_WAIT: + case TCP_CLOSE: + /* FALLTHRU */ + sk->sk_user_data = NULL; + nvmet_tcp_schedule_release_queue(queue); + break; + default: + pr_warn("queue %d unhandled state %d\n", + queue->idx, sk->sk_state); + } +done: + write_unlock_bh(&sk->sk_callback_lock); +} + +static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue) +{ + struct socket *sock = queue->sock; + struct linger sol = { .l_onoff = 1, .l_linger = 0 }; + int ret; + + ret = kernel_getsockname(sock, + (struct sockaddr *)&queue->sockaddr); + if (ret < 0) + return ret; + + ret = kernel_getpeername(sock, + (struct sockaddr *)&queue->sockaddr_peer); + if (ret < 0) + return ret; + + /* + * Cleanup whatever is sitting in the TCP transmit queue on socket + * close. This is done to prevent stale data from being sent should + * the network connection be restored before TCP times out. + */ + ret = kernel_setsockopt(sock, SOL_SOCKET, SO_LINGER, + (char *)&sol, sizeof(sol)); + if (ret) + return ret; + + write_lock_bh(&sock->sk->sk_callback_lock); + sock->sk->sk_user_data = queue; + queue->data_ready = sock->sk->sk_data_ready; + sock->sk->sk_data_ready = nvmet_tcp_data_ready; + queue->state_change = sock->sk->sk_state_change; + sock->sk->sk_state_change = nvmet_tcp_state_change; + queue->write_space = sock->sk->sk_write_space; + sock->sk->sk_write_space = nvmet_tcp_write_space; + write_unlock_bh(&sock->sk->sk_callback_lock); + + return 0; +} + +static int nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port, + struct socket *newsock) +{ + struct nvmet_tcp_queue *queue; + int ret; + + queue = kzalloc(sizeof(*queue), GFP_KERNEL); + if (!queue) + return -ENOMEM; + + INIT_WORK(&queue->release_work, nvmet_tcp_release_queue_work); + INIT_WORK(&queue->io_work, nvmet_tcp_io_work); + queue->sock = newsock; + queue->port = port; + queue->nr_cmds = 0; + spin_lock_init(&queue->state_lock); + queue->state = NVMET_TCP_Q_CONNECTING; + INIT_LIST_HEAD(&queue->free_list); + init_llist_head(&queue->resp_list); + INIT_LIST_HEAD(&queue->resp_send_list); + + queue->idx = ida_simple_get(&nvmet_tcp_queue_ida, 0, 0, GFP_KERNEL); + if (queue->idx < 0) { + ret = queue->idx; + goto out_free_queue; + } + + ret = nvmet_tcp_alloc_cmd(queue, &queue->connect); + if (ret) + goto out_ida_remove; + + ret = nvmet_sq_init(&queue->nvme_sq); + if (ret) + goto out_free_connect; + + port->last_cpu = cpumask_next_wrap(port->last_cpu, + cpu_online_mask, -1, false); + queue->cpu = port->last_cpu; + nvmet_prepare_receive_pdu(queue); + + mutex_lock(&nvmet_tcp_queue_mutex); + list_add_tail(&queue->queue_list, &nvmet_tcp_queue_list); + mutex_unlock(&nvmet_tcp_queue_mutex); + + ret = nvmet_tcp_set_queue_sock(queue); + if (ret) + goto out_destroy_sq; + + queue_work_on(queue->cpu, nvmet_tcp_wq, &queue->io_work); + + return 0; +out_destroy_sq: + mutex_lock(&nvmet_tcp_queue_mutex); + list_del_init(&queue->queue_list); + mutex_unlock(&nvmet_tcp_queue_mutex); + nvmet_sq_destroy(&queue->nvme_sq); +out_free_connect: + nvmet_tcp_free_cmd(&queue->connect); +out_ida_remove: + ida_simple_remove(&nvmet_tcp_queue_ida, queue->idx); +out_free_queue: + kfree(queue); + return ret; +} + +static void nvmet_tcp_accept_work(struct work_struct *w) +{ + struct nvmet_tcp_port *port = + container_of(w, struct nvmet_tcp_port, accept_work); + struct socket *newsock; + int ret; + + while (true) { + ret = kernel_accept(port->sock, &newsock, O_NONBLOCK); + if (ret < 0) { + if (ret != -EAGAIN) + pr_warn("failed to accept err=%d\n", ret); + return; + } + ret = nvmet_tcp_alloc_queue(port, newsock); + if (ret) { + pr_err("failed to allocate queue\n"); + sock_release(newsock); + } + } +} + +static void nvmet_tcp_listen_data_ready(struct sock *sk) +{ + struct nvmet_tcp_port *port; + + read_lock_bh(&sk->sk_callback_lock); + port = sk->sk_user_data; + if (!port) + goto out; + + if (sk->sk_state == TCP_LISTEN) + schedule_work(&port->accept_work); +out: + read_unlock_bh(&sk->sk_callback_lock); +} + +static int nvmet_tcp_add_port(struct nvmet_port *nport) +{ + struct nvmet_tcp_port *port; + __kernel_sa_family_t af; + int opt, ret; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + 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 err_port; + } + + 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 err_port; + } + + port->nport = nport; + port->last_cpu = -1; + INIT_WORK(&port->accept_work, nvmet_tcp_accept_work); + if (port->nport->inline_data_size < 0) + port->nport->inline_data_size = NVMET_TCP_DEF_INLINE_DATA_SIZE; + + ret = sock_create(port->addr.ss_family, SOCK_STREAM, + IPPROTO_TCP, &port->sock); + if (ret) { + pr_err("failed to create a socket\n"); + goto err_port; + } + + port->sock->sk->sk_user_data = port; + port->data_ready = port->sock->sk->sk_data_ready; + port->sock->sk->sk_data_ready = nvmet_tcp_listen_data_ready; + + opt = 1; + ret = kernel_setsockopt(port->sock, IPPROTO_TCP, + TCP_NODELAY, (char *)&opt, sizeof(opt)); + if (ret) { + pr_err("failed to set TCP_NODELAY sock opt %d\n", ret); + goto err_sock; + } + + ret = kernel_setsockopt(port->sock, SOL_SOCKET, SO_REUSEADDR, + (char *)&opt, sizeof(opt)); + if (ret) { + pr_err("failed to set SO_REUSEADDR sock opt %d\n", ret); + goto err_sock; + } + + ret = kernel_bind(port->sock, (struct sockaddr *)&port->addr, + sizeof(port->addr)); + if (ret) { + pr_err("failed to bind port socket %d\n", ret); + goto err_sock; + } + + ret = kernel_listen(port->sock, 128); + if (ret) { + pr_err("failed to listen %d on port sock\n", ret); + goto err_sock; + } + + nport->priv = port; + pr_info("enabling port %d (%pISpc)\n", + le16_to_cpu(nport->disc_addr.portid), &port->addr); + + return 0; + +err_sock: + sock_release(port->sock); +err_port: + kfree(port); + return ret; +} + +static void nvmet_tcp_remove_port(struct nvmet_port *nport) +{ + struct nvmet_tcp_port *port = nport->priv; + + write_lock_bh(&port->sock->sk->sk_callback_lock); + port->sock->sk->sk_data_ready = port->data_ready; + port->sock->sk->sk_user_data = NULL; + write_unlock_bh(&port->sock->sk->sk_callback_lock); + cancel_work_sync(&port->accept_work); + + sock_release(port->sock); + kfree(port); +} + +static void nvmet_tcp_delete_ctrl(struct nvmet_ctrl *ctrl) +{ + struct nvmet_tcp_queue *queue; + + mutex_lock(&nvmet_tcp_queue_mutex); + list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list) + if (queue->nvme_sq.ctrl == ctrl) + kernel_sock_shutdown(queue->sock, SHUT_RDWR); + mutex_unlock(&nvmet_tcp_queue_mutex); +} + +static u16 nvmet_tcp_install_queue(struct nvmet_sq *sq) +{ + struct nvmet_tcp_queue *queue = + container_of(sq, struct nvmet_tcp_queue, nvme_sq); + + if (sq->qid == 0) { + /* Let inflight controller teardown complete */ + flush_scheduled_work(); + } + + queue->nr_cmds = sq->size * 2; + if (nvmet_tcp_alloc_cmds(queue)) + return NVME_SC_INTERNAL; + return 0; +} + +static void nvmet_tcp_disc_port_addr(struct nvmet_req *req, + struct nvmet_port *nport, char *traddr) +{ + struct nvmet_tcp_port *port = nport->priv; + + if (inet_addr_is_any((struct sockaddr *)&port->addr)) { + struct nvmet_tcp_cmd *cmd = + container_of(req, struct nvmet_tcp_cmd, req); + struct nvmet_tcp_queue *queue = cmd->queue; + + sprintf(traddr, "%pISc", (struct sockaddr *)&queue->sockaddr); + } else { + memcpy(traddr, nport->disc_addr.traddr, NVMF_TRADDR_SIZE); + } +} + +static struct nvmet_fabrics_ops nvmet_tcp_ops = { + .owner = THIS_MODULE, + .type = NVMF_TRTYPE_TCP, + .msdbd = 1, + .has_keyed_sgls = 0, + .add_port = nvmet_tcp_add_port, + .remove_port = nvmet_tcp_remove_port, + .queue_response = nvmet_tcp_queue_response, + .delete_ctrl = nvmet_tcp_delete_ctrl, + .install_queue = nvmet_tcp_install_queue, + .disc_traddr = nvmet_tcp_disc_port_addr, +}; + +static int __init nvmet_tcp_init(void) +{ + int ret; + + nvmet_tcp_wq = alloc_workqueue("nvmet_tcp_wq", WQ_HIGHPRI, 0); + if (!nvmet_tcp_wq) + return -ENOMEM; + + ret = nvmet_register_transport(&nvmet_tcp_ops); + if (ret) + goto err; + + return 0; +err: + destroy_workqueue(nvmet_tcp_wq); + return ret; +} + +static void __exit nvmet_tcp_exit(void) +{ + struct nvmet_tcp_queue *queue; + + nvmet_unregister_transport(&nvmet_tcp_ops); + + flush_scheduled_work(); + mutex_lock(&nvmet_tcp_queue_mutex); + list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list) + kernel_sock_shutdown(queue->sock, SHUT_RDWR); + mutex_unlock(&nvmet_tcp_queue_mutex); + flush_scheduled_work(); + + destroy_workqueue(nvmet_tcp_wq); +} + +module_init(nvmet_tcp_init); +module_exit(nvmet_tcp_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("nvmet-transport-3"); /* 3 == NVMF_TRTYPE_TCP */ |