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nbd: add multi-connection support
NBD can become contended on its single connection. We have to serialize all writes and we can only process one read response at a time. Fix this by allowing userspace to provide multiple connections to a single nbd device. This coupled with block-mq drastically increases performance in multi-process cases. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Josef Bacik
Jens Axboe
parent
e00f4f4d0f
commit
9561a7ade0
@ -41,26 +41,34 @@
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#include <linux/nbd.h>
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struct nbd_sock {
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struct socket *sock;
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struct mutex tx_lock;
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};
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#define NBD_TIMEDOUT 0
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#define NBD_DISCONNECT_REQUESTED 1
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#define NBD_DISCONNECTED 2
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#define NBD_RUNNING 3
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struct nbd_device {
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u32 flags;
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unsigned long runtime_flags;
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struct socket * sock; /* If == NULL, device is not ready, yet */
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struct nbd_sock **socks;
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int magic;
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struct blk_mq_tag_set tag_set;
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struct mutex tx_lock;
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struct mutex config_lock;
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struct gendisk *disk;
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int num_connections;
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atomic_t recv_threads;
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wait_queue_head_t recv_wq;
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int blksize;
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loff_t bytesize;
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/* protects initialization and shutdown of the socket */
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spinlock_t sock_lock;
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struct task_struct *task_recv;
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struct task_struct *task_send;
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struct task_struct *task_setup;
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#if IS_ENABLED(CONFIG_DEBUG_FS)
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struct dentry *dbg_dir;
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@ -69,7 +77,7 @@ struct nbd_device {
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struct nbd_cmd {
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struct nbd_device *nbd;
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struct list_head list;
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struct completion send_complete;
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};
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#if IS_ENABLED(CONFIG_DEBUG_FS)
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@ -159,22 +167,20 @@ static void nbd_end_request(struct nbd_cmd *cmd)
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*/
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static void sock_shutdown(struct nbd_device *nbd)
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{
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struct socket *sock;
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int i;
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spin_lock(&nbd->sock_lock);
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if (!nbd->sock) {
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spin_unlock_irq(&nbd->sock_lock);
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if (nbd->num_connections == 0)
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return;
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if (test_and_set_bit(NBD_DISCONNECTED, &nbd->runtime_flags))
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return;
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for (i = 0; i < nbd->num_connections; i++) {
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struct nbd_sock *nsock = nbd->socks[i];
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mutex_lock(&nsock->tx_lock);
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kernel_sock_shutdown(nsock->sock, SHUT_RDWR);
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mutex_unlock(&nsock->tx_lock);
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}
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sock = nbd->sock;
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dev_warn(disk_to_dev(nbd->disk), "shutting down socket\n");
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nbd->sock = NULL;
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spin_unlock(&nbd->sock_lock);
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kernel_sock_shutdown(sock, SHUT_RDWR);
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sockfd_put(sock);
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dev_warn(disk_to_dev(nbd->disk), "shutting down sockets\n");
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}
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static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
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@ -182,35 +188,31 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
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{
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struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req);
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struct nbd_device *nbd = cmd->nbd;
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struct socket *sock = NULL;
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spin_lock(&nbd->sock_lock);
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set_bit(NBD_TIMEDOUT, &nbd->runtime_flags);
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if (nbd->sock) {
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sock = nbd->sock;
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get_file(sock->file);
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}
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spin_unlock(&nbd->sock_lock);
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if (sock) {
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kernel_sock_shutdown(sock, SHUT_RDWR);
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sockfd_put(sock);
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}
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req->errors++;
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dev_err(nbd_to_dev(nbd), "Connection timed out, shutting down connection\n");
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set_bit(NBD_TIMEDOUT, &nbd->runtime_flags);
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req->errors++;
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/*
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* If our disconnect packet times out then we're already holding the
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* config_lock and could deadlock here, so just set an error and return,
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* we'll handle shutting everything down later.
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*/
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if (req->cmd_type == REQ_TYPE_DRV_PRIV)
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return BLK_EH_HANDLED;
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mutex_lock(&nbd->config_lock);
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sock_shutdown(nbd);
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mutex_unlock(&nbd->config_lock);
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return BLK_EH_HANDLED;
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}
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/*
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* Send or receive packet.
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*/
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static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size,
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int msg_flags)
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static int sock_xmit(struct nbd_device *nbd, int index, int send, void *buf,
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int size, int msg_flags)
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{
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struct socket *sock = nbd->sock;
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struct socket *sock = nbd->socks[index]->sock;
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int result;
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struct msghdr msg;
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struct kvec iov;
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@ -254,19 +256,19 @@ static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size,
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return result;
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}
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static inline int sock_send_bvec(struct nbd_device *nbd, struct bio_vec *bvec,
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int flags)
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static inline int sock_send_bvec(struct nbd_device *nbd, int index,
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struct bio_vec *bvec, int flags)
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{
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int result;
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void *kaddr = kmap(bvec->bv_page);
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result = sock_xmit(nbd, 1, kaddr + bvec->bv_offset,
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result = sock_xmit(nbd, index, 1, kaddr + bvec->bv_offset,
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bvec->bv_len, flags);
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kunmap(bvec->bv_page);
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return result;
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}
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/* always call with the tx_lock held */
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static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd)
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static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
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{
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struct request *req = blk_mq_rq_from_pdu(cmd);
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int result, flags;
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@ -274,10 +276,9 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd)
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unsigned long size = blk_rq_bytes(req);
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struct bio *bio;
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u32 type;
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u32 tag = blk_mq_unique_tag(req);
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if (req->cmd_type == REQ_TYPE_DRV_PRIV)
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type = NBD_CMD_DISC;
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else if (req_op(req) == REQ_OP_DISCARD)
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if (req_op(req) == REQ_OP_DISCARD)
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type = NBD_CMD_TRIM;
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else if (req_op(req) == REQ_OP_FLUSH)
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type = NBD_CMD_FLUSH;
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@ -289,16 +290,16 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd)
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memset(&request, 0, sizeof(request));
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request.magic = htonl(NBD_REQUEST_MAGIC);
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request.type = htonl(type);
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if (type != NBD_CMD_FLUSH && type != NBD_CMD_DISC) {
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if (type != NBD_CMD_FLUSH) {
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request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9);
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request.len = htonl(size);
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}
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memcpy(request.handle, &req->tag, sizeof(req->tag));
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memcpy(request.handle, &tag, sizeof(tag));
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dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n",
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cmd, nbdcmd_to_ascii(type),
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(unsigned long long)blk_rq_pos(req) << 9, blk_rq_bytes(req));
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result = sock_xmit(nbd, 1, &request, sizeof(request),
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result = sock_xmit(nbd, index, 1, &request, sizeof(request),
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(type == NBD_CMD_WRITE) ? MSG_MORE : 0);
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if (result <= 0) {
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dev_err(disk_to_dev(nbd->disk),
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@ -323,7 +324,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd)
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flags = MSG_MORE;
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dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n",
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cmd, bvec.bv_len);
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result = sock_send_bvec(nbd, &bvec, flags);
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result = sock_send_bvec(nbd, index, &bvec, flags);
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if (result <= 0) {
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dev_err(disk_to_dev(nbd->disk),
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"Send data failed (result %d)\n",
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@ -344,31 +345,34 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd)
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return 0;
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}
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static inline int sock_recv_bvec(struct nbd_device *nbd, struct bio_vec *bvec)
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static inline int sock_recv_bvec(struct nbd_device *nbd, int index,
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struct bio_vec *bvec)
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{
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int result;
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void *kaddr = kmap(bvec->bv_page);
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result = sock_xmit(nbd, 0, kaddr + bvec->bv_offset, bvec->bv_len,
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MSG_WAITALL);
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result = sock_xmit(nbd, index, 0, kaddr + bvec->bv_offset,
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bvec->bv_len, MSG_WAITALL);
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kunmap(bvec->bv_page);
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return result;
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}
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/* NULL returned = something went wrong, inform userspace */
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static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd)
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static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
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{
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int result;
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struct nbd_reply reply;
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struct nbd_cmd *cmd;
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struct request *req = NULL;
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u16 hwq;
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int tag;
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u32 tag;
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reply.magic = 0;
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result = sock_xmit(nbd, 0, &reply, sizeof(reply), MSG_WAITALL);
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result = sock_xmit(nbd, index, 0, &reply, sizeof(reply), MSG_WAITALL);
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if (result <= 0) {
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dev_err(disk_to_dev(nbd->disk),
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"Receive control failed (result %d)\n", result);
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if (!test_bit(NBD_DISCONNECTED, &nbd->runtime_flags) &&
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!test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags))
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dev_err(disk_to_dev(nbd->disk),
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"Receive control failed (result %d)\n", result);
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return ERR_PTR(result);
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}
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@ -378,7 +382,7 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd)
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return ERR_PTR(-EPROTO);
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}
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memcpy(&tag, reply.handle, sizeof(int));
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memcpy(&tag, reply.handle, sizeof(u32));
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hwq = blk_mq_unique_tag_to_hwq(tag);
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if (hwq < nbd->tag_set.nr_hw_queues)
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@ -390,7 +394,6 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd)
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return ERR_PTR(-ENOENT);
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}
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cmd = blk_mq_rq_to_pdu(req);
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if (ntohl(reply.error)) {
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dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n",
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ntohl(reply.error));
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@ -404,7 +407,7 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd)
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struct bio_vec bvec;
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rq_for_each_segment(bvec, req, iter) {
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result = sock_recv_bvec(nbd, &bvec);
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result = sock_recv_bvec(nbd, index, &bvec);
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if (result <= 0) {
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dev_err(disk_to_dev(nbd->disk), "Receive data failed (result %d)\n",
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result);
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@ -414,6 +417,9 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd)
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dev_dbg(nbd_to_dev(nbd), "request %p: got %d bytes data\n",
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cmd, bvec.bv_len);
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}
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} else {
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/* See the comment in nbd_queue_rq. */
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wait_for_completion(&cmd->send_complete);
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}
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return cmd;
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}
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@ -432,25 +438,24 @@ static struct device_attribute pid_attr = {
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.show = pid_show,
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};
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static int nbd_thread_recv(struct nbd_device *nbd, struct block_device *bdev)
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struct recv_thread_args {
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struct work_struct work;
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struct nbd_device *nbd;
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int index;
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};
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static void recv_work(struct work_struct *work)
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{
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struct recv_thread_args *args = container_of(work,
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struct recv_thread_args,
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work);
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struct nbd_device *nbd = args->nbd;
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struct nbd_cmd *cmd;
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int ret;
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int ret = 0;
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BUG_ON(nbd->magic != NBD_MAGIC);
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sk_set_memalloc(nbd->sock->sk);
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ret = device_create_file(disk_to_dev(nbd->disk), &pid_attr);
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if (ret) {
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dev_err(disk_to_dev(nbd->disk), "device_create_file failed!\n");
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return ret;
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}
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nbd_size_update(nbd, bdev);
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while (1) {
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cmd = nbd_read_stat(nbd);
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cmd = nbd_read_stat(nbd, args->index);
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if (IS_ERR(cmd)) {
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ret = PTR_ERR(cmd);
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break;
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@ -459,10 +464,14 @@ static int nbd_thread_recv(struct nbd_device *nbd, struct block_device *bdev)
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nbd_end_request(cmd);
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}
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nbd_size_clear(nbd, bdev);
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device_remove_file(disk_to_dev(nbd->disk), &pid_attr);
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return ret;
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/*
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* We got an error, shut everybody down if this wasn't the result of a
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* disconnect request.
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*/
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if (ret && !test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags))
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sock_shutdown(nbd);
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atomic_dec(&nbd->recv_threads);
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wake_up(&nbd->recv_wq);
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}
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static void nbd_clear_req(struct request *req, void *data, bool reserved)
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@ -480,26 +489,35 @@ static void nbd_clear_que(struct nbd_device *nbd)
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{
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BUG_ON(nbd->magic != NBD_MAGIC);
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/*
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* Because we have set nbd->sock to NULL under the tx_lock, all
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* modifications to the list must have completed by now.
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*/
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BUG_ON(nbd->sock);
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blk_mq_tagset_busy_iter(&nbd->tag_set, nbd_clear_req, NULL);
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dev_dbg(disk_to_dev(nbd->disk), "queue cleared\n");
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}
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static void nbd_handle_cmd(struct nbd_cmd *cmd)
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static void nbd_handle_cmd(struct nbd_cmd *cmd, int index)
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{
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struct request *req = blk_mq_rq_from_pdu(cmd);
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struct nbd_device *nbd = cmd->nbd;
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struct nbd_sock *nsock;
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if (req->cmd_type != REQ_TYPE_FS)
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if (index >= nbd->num_connections) {
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dev_err(disk_to_dev(nbd->disk),
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"Attempted send on invalid socket\n");
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goto error_out;
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}
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if (test_bit(NBD_DISCONNECTED, &nbd->runtime_flags)) {
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dev_err(disk_to_dev(nbd->disk),
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"Attempted send on closed socket\n");
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goto error_out;
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}
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if (req->cmd_type != REQ_TYPE_FS &&
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req->cmd_type != REQ_TYPE_DRV_PRIV)
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goto error_out;
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if (rq_data_dir(req) == WRITE &&
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if (req->cmd_type == REQ_TYPE_FS &&
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rq_data_dir(req) == WRITE &&
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(nbd->flags & NBD_FLAG_READ_ONLY)) {
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dev_err(disk_to_dev(nbd->disk),
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"Write on read-only\n");
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@ -508,23 +526,22 @@ static void nbd_handle_cmd(struct nbd_cmd *cmd)
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req->errors = 0;
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mutex_lock(&nbd->tx_lock);
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nbd->task_send = current;
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if (unlikely(!nbd->sock)) {
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mutex_unlock(&nbd->tx_lock);
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nsock = nbd->socks[index];
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mutex_lock(&nsock->tx_lock);
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if (unlikely(!nsock->sock)) {
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mutex_unlock(&nsock->tx_lock);
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dev_err(disk_to_dev(nbd->disk),
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"Attempted send on closed socket\n");
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goto error_out;
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}
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if (nbd_send_cmd(nbd, cmd) != 0) {
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if (nbd_send_cmd(nbd, cmd, index) != 0) {
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dev_err(disk_to_dev(nbd->disk), "Request send failed\n");
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req->errors++;
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nbd_end_request(cmd);
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}
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nbd->task_send = NULL;
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mutex_unlock(&nbd->tx_lock);
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mutex_unlock(&nsock->tx_lock);
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return;
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@ -538,39 +555,70 @@ static int nbd_queue_rq(struct blk_mq_hw_ctx *hctx,
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{
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struct nbd_cmd *cmd = blk_mq_rq_to_pdu(bd->rq);
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/*
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* Since we look at the bio's to send the request over the network we
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* need to make sure the completion work doesn't mark this request done
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* before we are done doing our send. This keeps us from dereferencing
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* freed data if we have particularly fast completions (ie we get the
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* completion before we exit sock_xmit on the last bvec) or in the case
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* that the server is misbehaving (or there was an error) before we're
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* done sending everything over the wire.
|
||||
*/
|
||||
init_completion(&cmd->send_complete);
|
||||
blk_mq_start_request(bd->rq);
|
||||
nbd_handle_cmd(cmd);
|
||||
nbd_handle_cmd(cmd, hctx->queue_num);
|
||||
complete(&cmd->send_complete);
|
||||
|
||||
return BLK_MQ_RQ_QUEUE_OK;
|
||||
}
|
||||
|
||||
static int nbd_set_socket(struct nbd_device *nbd, struct socket *sock)
|
||||
static int nbd_add_socket(struct nbd_device *nbd, struct socket *sock)
|
||||
{
|
||||
int ret = 0;
|
||||
struct nbd_sock **socks;
|
||||
struct nbd_sock *nsock;
|
||||
|
||||
spin_lock_irq(&nbd->sock_lock);
|
||||
|
||||
if (nbd->sock) {
|
||||
ret = -EBUSY;
|
||||
goto out;
|
||||
if (!nbd->task_setup)
|
||||
nbd->task_setup = current;
|
||||
if (nbd->task_setup != current) {
|
||||
dev_err(disk_to_dev(nbd->disk),
|
||||
"Device being setup by another task");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
nbd->sock = sock;
|
||||
socks = krealloc(nbd->socks, (nbd->num_connections + 1) *
|
||||
sizeof(struct nbd_sock *), GFP_KERNEL);
|
||||
if (!socks)
|
||||
return -ENOMEM;
|
||||
nsock = kzalloc(sizeof(struct nbd_sock), GFP_KERNEL);
|
||||
if (!nsock)
|
||||
return -ENOMEM;
|
||||
|
||||
out:
|
||||
spin_unlock_irq(&nbd->sock_lock);
|
||||
nbd->socks = socks;
|
||||
|
||||
return ret;
|
||||
mutex_init(&nsock->tx_lock);
|
||||
nsock->sock = sock;
|
||||
socks[nbd->num_connections++] = nsock;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Reset all properties of an NBD device */
|
||||
static void nbd_reset(struct nbd_device *nbd)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < nbd->num_connections; i++)
|
||||
kfree(nbd->socks[i]);
|
||||
kfree(nbd->socks);
|
||||
nbd->socks = NULL;
|
||||
nbd->runtime_flags = 0;
|
||||
nbd->blksize = 1024;
|
||||
nbd->bytesize = 0;
|
||||
set_capacity(nbd->disk, 0);
|
||||
nbd->flags = 0;
|
||||
nbd->tag_set.timeout = 0;
|
||||
nbd->num_connections = 0;
|
||||
nbd->task_setup = NULL;
|
||||
queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue);
|
||||
}
|
||||
|
||||
@ -596,41 +644,46 @@ static void nbd_parse_flags(struct nbd_device *nbd, struct block_device *bdev)
|
||||
blk_queue_write_cache(nbd->disk->queue, false, false);
|
||||
}
|
||||
|
||||
static void send_disconnects(struct nbd_device *nbd)
|
||||
{
|
||||
struct nbd_request request = {};
|
||||
int i, ret;
|
||||
|
||||
request.magic = htonl(NBD_REQUEST_MAGIC);
|
||||
request.type = htonl(NBD_CMD_DISC);
|
||||
|
||||
for (i = 0; i < nbd->num_connections; i++) {
|
||||
ret = sock_xmit(nbd, i, 1, &request, sizeof(request), 0);
|
||||
if (ret <= 0)
|
||||
dev_err(disk_to_dev(nbd->disk),
|
||||
"Send disconnect failed %d\n", ret);
|
||||
}
|
||||
}
|
||||
|
||||
static int nbd_dev_dbg_init(struct nbd_device *nbd);
|
||||
static void nbd_dev_dbg_close(struct nbd_device *nbd);
|
||||
|
||||
/* Must be called with tx_lock held */
|
||||
|
||||
/* Must be called with config_lock held */
|
||||
static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
|
||||
unsigned int cmd, unsigned long arg)
|
||||
{
|
||||
switch (cmd) {
|
||||
case NBD_DISCONNECT: {
|
||||
struct request *sreq;
|
||||
|
||||
dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n");
|
||||
if (!nbd->sock)
|
||||
if (!nbd->socks)
|
||||
return -EINVAL;
|
||||
|
||||
sreq = blk_mq_alloc_request(bdev_get_queue(bdev), WRITE, 0);
|
||||
if (!sreq)
|
||||
return -ENOMEM;
|
||||
|
||||
mutex_unlock(&nbd->tx_lock);
|
||||
mutex_unlock(&nbd->config_lock);
|
||||
fsync_bdev(bdev);
|
||||
mutex_lock(&nbd->tx_lock);
|
||||
sreq->cmd_type = REQ_TYPE_DRV_PRIV;
|
||||
mutex_lock(&nbd->config_lock);
|
||||
|
||||
/* Check again after getting mutex back. */
|
||||
if (!nbd->sock) {
|
||||
blk_mq_free_request(sreq);
|
||||
if (!nbd->socks)
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
set_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags);
|
||||
|
||||
nbd_send_cmd(nbd, blk_mq_rq_to_pdu(sreq));
|
||||
blk_mq_free_request(sreq);
|
||||
if (!test_and_set_bit(NBD_DISCONNECT_REQUESTED,
|
||||
&nbd->runtime_flags))
|
||||
send_disconnects(nbd);
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -638,6 +691,20 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
|
||||
sock_shutdown(nbd);
|
||||
nbd_clear_que(nbd);
|
||||
kill_bdev(bdev);
|
||||
nbd_bdev_reset(bdev);
|
||||
/*
|
||||
* We want to give the run thread a chance to wait for everybody
|
||||
* to clean up and then do it's own cleanup.
|
||||
*/
|
||||
if (!test_bit(NBD_RUNNING, &nbd->runtime_flags)) {
|
||||
int i;
|
||||
|
||||
for (i = 0; i < nbd->num_connections; i++)
|
||||
kfree(nbd->socks[i]);
|
||||
kfree(nbd->socks);
|
||||
nbd->socks = NULL;
|
||||
nbd->num_connections = 0;
|
||||
}
|
||||
return 0;
|
||||
|
||||
case NBD_SET_SOCK: {
|
||||
@ -647,7 +714,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
|
||||
if (!sock)
|
||||
return err;
|
||||
|
||||
err = nbd_set_socket(nbd, sock);
|
||||
err = nbd_add_socket(nbd, sock);
|
||||
if (!err && max_part)
|
||||
bdev->bd_invalidated = 1;
|
||||
|
||||
@ -676,26 +743,58 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
|
||||
return 0;
|
||||
|
||||
case NBD_DO_IT: {
|
||||
int error;
|
||||
struct recv_thread_args *args;
|
||||
int num_connections = nbd->num_connections;
|
||||
int error, i;
|
||||
|
||||
if (nbd->task_recv)
|
||||
return -EBUSY;
|
||||
if (!nbd->sock)
|
||||
if (!nbd->socks)
|
||||
return -EINVAL;
|
||||
if (num_connections > 1 &&
|
||||
!(nbd->flags & NBD_FLAG_CAN_MULTI_CONN)) {
|
||||
dev_err(disk_to_dev(nbd->disk), "server does not support multiple connections per device.\n");
|
||||
goto out_err;
|
||||
}
|
||||
|
||||
/* We have to claim the device under the lock */
|
||||
set_bit(NBD_RUNNING, &nbd->runtime_flags);
|
||||
blk_mq_update_nr_hw_queues(&nbd->tag_set, nbd->num_connections);
|
||||
args = kcalloc(num_connections, sizeof(*args), GFP_KERNEL);
|
||||
if (!args)
|
||||
goto out_err;
|
||||
nbd->task_recv = current;
|
||||
mutex_unlock(&nbd->tx_lock);
|
||||
mutex_unlock(&nbd->config_lock);
|
||||
|
||||
nbd_parse_flags(nbd, bdev);
|
||||
|
||||
error = device_create_file(disk_to_dev(nbd->disk), &pid_attr);
|
||||
if (error) {
|
||||
dev_err(disk_to_dev(nbd->disk), "device_create_file failed!\n");
|
||||
goto out_recv;
|
||||
}
|
||||
|
||||
nbd_size_update(nbd, bdev);
|
||||
|
||||
nbd_dev_dbg_init(nbd);
|
||||
error = nbd_thread_recv(nbd, bdev);
|
||||
for (i = 0; i < num_connections; i++) {
|
||||
sk_set_memalloc(nbd->socks[i]->sock->sk);
|
||||
atomic_inc(&nbd->recv_threads);
|
||||
INIT_WORK(&args[i].work, recv_work);
|
||||
args[i].nbd = nbd;
|
||||
args[i].index = i;
|
||||
queue_work(system_long_wq, &args[i].work);
|
||||
}
|
||||
wait_event_interruptible(nbd->recv_wq,
|
||||
atomic_read(&nbd->recv_threads) == 0);
|
||||
for (i = 0; i < num_connections; i++)
|
||||
flush_work(&args[i].work);
|
||||
nbd_dev_dbg_close(nbd);
|
||||
|
||||
mutex_lock(&nbd->tx_lock);
|
||||
nbd_size_clear(nbd, bdev);
|
||||
device_remove_file(disk_to_dev(nbd->disk), &pid_attr);
|
||||
out_recv:
|
||||
mutex_lock(&nbd->config_lock);
|
||||
nbd->task_recv = NULL;
|
||||
|
||||
out_err:
|
||||
sock_shutdown(nbd);
|
||||
nbd_clear_que(nbd);
|
||||
kill_bdev(bdev);
|
||||
@ -708,7 +807,6 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
|
||||
error = -ETIMEDOUT;
|
||||
|
||||
nbd_reset(nbd);
|
||||
|
||||
return error;
|
||||
}
|
||||
|
||||
@ -740,9 +838,9 @@ static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
|
||||
|
||||
BUG_ON(nbd->magic != NBD_MAGIC);
|
||||
|
||||
mutex_lock(&nbd->tx_lock);
|
||||
mutex_lock(&nbd->config_lock);
|
||||
error = __nbd_ioctl(bdev, nbd, cmd, arg);
|
||||
mutex_unlock(&nbd->tx_lock);
|
||||
mutex_unlock(&nbd->config_lock);
|
||||
|
||||
return error;
|
||||
}
|
||||
@ -762,8 +860,6 @@ static int nbd_dbg_tasks_show(struct seq_file *s, void *unused)
|
||||
|
||||
if (nbd->task_recv)
|
||||
seq_printf(s, "recv: %d\n", task_pid_nr(nbd->task_recv));
|
||||
if (nbd->task_send)
|
||||
seq_printf(s, "send: %d\n", task_pid_nr(nbd->task_send));
|
||||
|
||||
return 0;
|
||||
}
|
||||
@ -887,9 +983,7 @@ static int nbd_init_request(void *data, struct request *rq,
|
||||
unsigned int numa_node)
|
||||
{
|
||||
struct nbd_cmd *cmd = blk_mq_rq_to_pdu(rq);
|
||||
|
||||
cmd->nbd = data;
|
||||
INIT_LIST_HEAD(&cmd->list);
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -999,13 +1093,13 @@ static int __init nbd_init(void)
|
||||
for (i = 0; i < nbds_max; i++) {
|
||||
struct gendisk *disk = nbd_dev[i].disk;
|
||||
nbd_dev[i].magic = NBD_MAGIC;
|
||||
spin_lock_init(&nbd_dev[i].sock_lock);
|
||||
mutex_init(&nbd_dev[i].tx_lock);
|
||||
mutex_init(&nbd_dev[i].config_lock);
|
||||
disk->major = NBD_MAJOR;
|
||||
disk->first_minor = i << part_shift;
|
||||
disk->fops = &nbd_fops;
|
||||
disk->private_data = &nbd_dev[i];
|
||||
sprintf(disk->disk_name, "nbd%d", i);
|
||||
init_waitqueue_head(&nbd_dev[i].recv_wq);
|
||||
nbd_reset(&nbd_dev[i]);
|
||||
add_disk(disk);
|
||||
}
|
||||
|
||||
@ -38,11 +38,12 @@ enum {
|
||||
};
|
||||
|
||||
/* values for flags field */
|
||||
#define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */
|
||||
#define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */
|
||||
#define NBD_FLAG_SEND_FLUSH (1 << 2) /* can flush writeback cache */
|
||||
#define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */
|
||||
#define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */
|
||||
#define NBD_FLAG_SEND_FLUSH (1 << 2) /* can flush writeback cache */
|
||||
/* there is a gap here to match userspace */
|
||||
#define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */
|
||||
#define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */
|
||||
#define NBD_FLAG_CAN_MULTI_CONN (1 << 7) /* Server supports multiple connections per export. */
|
||||
|
||||
/* userspace doesn't need the nbd_device structure */
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user