cregit-Linux how code gets into the kernel

Release 4.10 drivers/block/nbd.c

Directory: drivers/block
/*
 * Network block device - make block devices work over TCP
 *
 * Note that you can not swap over this thing, yet. Seems to work but
 * deadlocks sometimes - you can not swap over TCP in general.
 * 
 * Copyright 1997-2000, 2008 Pavel Machek <pavel@ucw.cz>
 * Parts copyright 2001 Steven Whitehouse <steve@chygwyn.com>
 *
 * This file is released under GPLv2 or later.
 *
 * (part of code stolen from loop.c)
 */

#include <linux/major.h>

#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/bio.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/ioctl.h>
#include <linux/mutex.h>
#include <linux/compiler.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <linux/net.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/debugfs.h>
#include <linux/blk-mq.h>

#include <linux/uaccess.h>
#include <asm/types.h>

#include <linux/nbd.h>


struct nbd_sock {
	
struct socket *sock;
	
struct mutex tx_lock;
};


#define NBD_TIMEDOUT			0

#define NBD_DISCONNECT_REQUESTED	1

#define NBD_DISCONNECTED		2

#define NBD_RUNNING			3


struct nbd_device {
	
u32 flags;
	
unsigned long runtime_flags;
	
struct nbd_sock **socks;
	
int magic;

	
struct blk_mq_tag_set tag_set;

	
struct mutex config_lock;
	
struct gendisk *disk;
	
int num_connections;
	
atomic_t recv_threads;
	
wait_queue_head_t recv_wq;
	
loff_t blksize;
	
loff_t bytesize;

	
struct task_struct *task_recv;
	
struct task_struct *task_setup;

#if IS_ENABLED(CONFIG_DEBUG_FS)
	
struct dentry *dbg_dir;
#endif
};


struct nbd_cmd {
	
struct nbd_device *nbd;
	
struct completion send_complete;
};

#if IS_ENABLED(CONFIG_DEBUG_FS)

static struct dentry *nbd_dbg_dir;
#endif


#define nbd_name(nbd) ((nbd)->disk->disk_name)


#define NBD_MAGIC 0x68797548


static unsigned int nbds_max = 16;

static struct nbd_device *nbd_dev;

static int max_part;


static inline struct device *nbd_to_dev(struct nbd_device *nbd) { return disk_to_dev(nbd->disk); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann1463.64%150.00%
andrew mortonandrew morton836.36%150.00%
Total22100.00%2100.00%


static bool nbd_is_connected(struct nbd_device *nbd) { return !!nbd->task_recv; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann18100.00%1100.00%
Total18100.00%1100.00%


static const char *nbdcmd_to_ascii(int cmd) { switch (cmd) { case NBD_CMD_READ: return "read"; case NBD_CMD_WRITE: return "write"; case NBD_CMD_DISC: return "disconnect"; case NBD_CMD_FLUSH: return "flush"; case NBD_CMD_TRIM: return "trim/discard"; } return "invalid"; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton3876.00%133.33%
paul clementspaul clements612.00%133.33%
alex blighalex bligh612.00%133.33%
Total50100.00%3100.00%


static int nbd_size_clear(struct nbd_device *nbd, struct block_device *bdev) { bdev->bd_inode->i_size = 0; set_capacity(nbd->disk, 0); kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann49100.00%1100.00%
Total49100.00%1100.00%


static void nbd_size_update(struct nbd_device *nbd, struct block_device *bdev) { if (!nbd_is_connected(nbd)) return; bdev->bd_inode->i_size = nbd->bytesize; set_capacity(nbd->disk, nbd->bytesize >> 9); kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann61100.00%1100.00%
Total61100.00%1100.00%


static int nbd_size_set(struct nbd_device *nbd, struct block_device *bdev, loff_t blocksize, loff_t nr_blocks) { int ret; ret = set_blocksize(bdev, blocksize); if (ret) return ret; nbd->blksize = blocksize; nbd->bytesize = blocksize * nr_blocks; nbd_size_update(nbd, bdev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann6396.92%150.00%
josef bacikjosef bacik23.08%150.00%
Total65100.00%2100.00%


static void nbd_end_request(struct nbd_cmd *cmd) { struct nbd_device *nbd = cmd->nbd; struct request *req = blk_mq_rq_from_pdu(cmd); int error = req->errors ? -EIO : 0; dev_dbg(nbd_to_dev(nbd), "request %p: %s\n", cmd, error ? "failed" : "done"); blk_mq_complete_request(req, error); }

Contributors

PersonTokensPropCommitsCommitProp
christoph hellwigchristoph hellwig2334.33%120.00%
josef bacikjosef bacik1928.36%120.00%
markus pargmannmarkus pargmann1014.93%120.00%
andrew mortonandrew morton811.94%120.00%
kiyoshi uedakiyoshi ueda710.45%120.00%
Total67100.00%5100.00%

/* * Forcibly shutdown the socket causing all listeners to error */
static void sock_shutdown(struct nbd_device *nbd) { int i; if (nbd->num_connections == 0) return; if (test_and_set_bit(NBD_DISCONNECTED, &nbd->runtime_flags)) return; for (i = 0; i < nbd->num_connections; i++) { struct nbd_sock *nsock = nbd->socks[i]; mutex_lock(&nsock->tx_lock); kernel_sock_shutdown(nsock->sock, SHUT_RDWR); mutex_unlock(&nsock->tx_lock); } dev_warn(disk_to_dev(nbd->disk), "shutting down sockets\n"); }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik7371.57%233.33%
paul clementspaul clements1514.71%116.67%
markus pargmannmarkus pargmann1110.78%233.33%
wanlong gaowanlong gao32.94%116.67%
Total102100.00%6100.00%


static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, bool reserved) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req); struct nbd_device *nbd = cmd->nbd; dev_err(nbd_to_dev(nbd), "Connection timed out, shutting down connection\n"); set_bit(NBD_TIMEDOUT, &nbd->runtime_flags); req->errors++; /* * If our disconnect packet times out then we're already holding the * config_lock and could deadlock here, so just set an error and return, * we'll handle shutting everything down later. */ if (req->cmd_type == REQ_TYPE_DRV_PRIV) return BLK_EH_HANDLED; mutex_lock(&nbd->config_lock); sock_shutdown(nbd); mutex_unlock(&nbd->config_lock); return BLK_EH_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik6467.37%450.00%
markus pargmannmarkus pargmann1920.00%337.50%
paul clementspaul clements1212.63%112.50%
Total95100.00%8100.00%

/* * Send or receive packet. */
static int sock_xmit(struct nbd_device *nbd, int index, int send, void *buf, int size, int msg_flags) { struct socket *sock = nbd->socks[index]->sock; int result; struct msghdr msg; struct kvec iov; unsigned long pflags = current->flags; if (unlikely(!sock)) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Attempted %s on closed socket in sock_xmit\n", (send ? "send" : "recv")); return -EINVAL; } current->flags |= PF_MEMALLOC; do { sock->sk->sk_allocation = GFP_NOIO | __GFP_MEMALLOC; iov.iov_base = buf; iov.iov_len = size; msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = msg_flags | MSG_NOSIGNAL; if (send) result = kernel_sendmsg(sock, &msg, &iov, 1, size); else result = kernel_recvmsg(sock, &msg, &iov, 1, size, msg.msg_flags); if (result <= 0) { if (result == 0) result = -EPIPE; /* short read */ break; } size -= result; buf += result; } while (size > 0); tsk_restore_flags(current, pflags, PF_MEMALLOC); return result; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git12952.02%317.65%
mike snitzermike snitzer2710.89%15.88%
mel gormanmel gorman2510.08%15.88%
andrew mortonandrew morton176.85%211.76%
al viroal viro135.24%15.88%
josef bacikjosef bacik93.63%211.76%
paul clementspaul clements93.63%15.88%
linus torvaldslinus torvalds72.82%211.76%
americo wangamerico wang52.02%15.88%
wanlong gaowanlong gao31.21%15.88%
namhyung kimnamhyung kim31.21%15.88%
david s. millerdavid s. miller10.40%15.88%
Total248100.00%17100.00%


static inline int sock_send_bvec(struct nbd_device *nbd, int index, struct bio_vec *bvec, int flags) { int result; void *kaddr = kmap(bvec->bv_page); result = sock_xmit(nbd, index, 1, kaddr + bvec->bv_offset, bvec->bv_len, flags); kunmap(bvec->bv_page); return result; }

Contributors

PersonTokensPropCommitsCommitProp
lou langholtzlou langholtz5984.29%120.00%
josef bacikjosef bacik57.14%120.00%
andrew mortonandrew morton34.29%120.00%
wanlong gaowanlong gao22.86%120.00%
paul clementspaul clements11.43%120.00%
Total70100.00%5100.00%

/* always call with the tx_lock held */
static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index) { struct request *req = blk_mq_rq_from_pdu(cmd); int result; struct nbd_request request; unsigned long size = blk_rq_bytes(req); struct bio *bio; u32 type; u32 tag = blk_mq_unique_tag(req); if (req_op(req) == REQ_OP_DISCARD) type = NBD_CMD_TRIM; else if (req_op(req) == REQ_OP_FLUSH) type = NBD_CMD_FLUSH; else if (rq_data_dir(req) == WRITE) type = NBD_CMD_WRITE; else type = NBD_CMD_READ; memset(&request, 0, sizeof(request)); request.magic = htonl(NBD_REQUEST_MAGIC); request.type = htonl(type); if (type != NBD_CMD_FLUSH) { request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9); request.len = htonl(size); } memcpy(request.handle, &tag, sizeof(tag)); dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n", cmd, nbdcmd_to_ascii(type), (unsigned long long)blk_rq_pos(req) << 9, blk_rq_bytes(req)); result = sock_xmit(nbd, index, 1, &request, sizeof(request), (type == NBD_CMD_WRITE) ? MSG_MORE : 0); if (result <= 0) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Send control failed (result %d)\n", result); return -EIO; } if (type != NBD_CMD_WRITE) return 0; bio = req->bio; while (bio) { struct bio *next = bio->bi_next; struct bvec_iter iter; struct bio_vec bvec; bio_for_each_segment(bvec, bio, iter) { bool is_last = !next && bio_iter_last(bvec, iter); int flags = is_last ? 0 : MSG_MORE; dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n", cmd, bvec.bv_len); result = sock_send_bvec(nbd, index, &bvec, flags); if (result <= 0) { dev_err(disk_to_dev(nbd->disk), "Send data failed (result %d)\n", result); return -EIO; } /* * The completion might already have come in, * so break for the last one instead of letting * the iterator do it. This prevents use-after-free * of the bio. */ if (is_last) break; } bio = next; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git11226.99%310.00%
jens axboejens axboe4811.57%13.33%
christoph hellwigchristoph hellwig4510.84%13.33%
andrew mortonandrew morton409.64%310.00%
josef bacikjosef bacik399.40%413.33%
linus torvaldslinus torvalds317.47%26.67%
markus pargmannmarkus pargmann204.82%26.67%
hani benhabileshani benhabiles143.37%13.33%
tejun heotejun heo122.89%26.67%
americo wangamerico wang112.65%13.33%
michael christiemichael christie102.41%26.67%
wanlong gaowanlong gao71.69%13.33%
neil brownneil brown71.69%13.33%
alex blighalex bligh61.45%13.33%
paul clementspaul clements51.20%13.33%
dave jonesdave jones40.96%13.33%
kent overstreetkent overstreet30.72%26.67%
lou langholtzlou langholtz10.24%13.33%
Total415100.00%30100.00%


static inline int sock_recv_bvec(struct nbd_device *nbd, int index, struct bio_vec *bvec) { int result; void *kaddr = kmap(bvec->bv_page); result = sock_xmit(nbd, index, 0, kaddr + bvec->bv_offset, bvec->bv_len, MSG_WAITALL); kunmap(bvec->bv_page); return result; }

Contributors

PersonTokensPropCommitsCommitProp
lou langholtzlou langholtz5683.58%120.00%
josef bacikjosef bacik57.46%120.00%
andrew mortonandrew morton34.48%120.00%
wanlong gaowanlong gao22.99%120.00%
paul clementspaul clements11.49%120.00%
Total67100.00%5100.00%

/* NULL returned = something went wrong, inform userspace */
static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index) { int result; struct nbd_reply reply; struct nbd_cmd *cmd; struct request *req = NULL; u16 hwq; u32 tag; reply.magic = 0; result = sock_xmit(nbd, index, 0, &reply, sizeof(reply), MSG_WAITALL); if (result <= 0) { if (!test_bit(NBD_DISCONNECTED, &nbd->runtime_flags) && !test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags)) dev_err(disk_to_dev(nbd->disk), "Receive control failed (result %d)\n", result); return ERR_PTR(result); } if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n", (unsigned long)ntohl(reply.magic)); return ERR_PTR(-EPROTO); } memcpy(&tag, reply.handle, sizeof(u32)); hwq = blk_mq_unique_tag_to_hwq(tag); if (hwq < nbd->tag_set.nr_hw_queues) req = blk_mq_tag_to_rq(nbd->tag_set.tags[hwq], blk_mq_unique_tag_to_tag(tag)); if (!req || !blk_mq_request_started(req)) { dev_err(disk_to_dev(nbd->disk), "Unexpected reply (%d) %p\n", tag, req); return ERR_PTR(-ENOENT); } cmd = blk_mq_rq_to_pdu(req); if (ntohl(reply.error)) { dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n", ntohl(reply.error)); req->errors++; return cmd; } dev_dbg(nbd_to_dev(nbd), "request %p: got reply\n", cmd); if (rq_data_dir(req) != WRITE) { struct req_iterator iter; struct bio_vec bvec; rq_for_each_segment(bvec, req, iter) { result = sock_recv_bvec(nbd, index, &bvec); if (result <= 0) { dev_err(disk_to_dev(nbd->disk), "Receive data failed (result %d)\n", result); req->errors++; return cmd; } dev_dbg(nbd_to_dev(nbd), "request %p: got %d bytes data\n", cmd, bvec.bv_len); } } else { /* See the comment in nbd_queue_rq. */ wait_for_completion(&cmd->send_complete); } return cmd; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik13332.52%28.33%
pre-gitpre-git9122.25%28.33%
andrew mortonandrew morton4611.25%312.50%
michal feixmichal feix389.29%28.33%
markus pargmannmarkus pargmann286.85%28.33%
americo wangamerico wang215.13%14.17%
lou langholtzlou langholtz112.69%14.17%
wanlong gaowanlong gao102.44%14.17%
herbert xuherbert xu92.20%14.17%
linus torvaldslinus torvalds81.96%416.67%
neil brownneil brown51.22%14.17%
christoph hellwigchristoph hellwig30.73%14.17%
dave jonesdave jones30.73%14.17%
kent overstreetkent overstreet20.49%14.17%
adrian bunkadrian bunk10.24%14.17%
Total409100.00%24100.00%


static ssize_t pid_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); struct nbd_device *nbd = (struct nbd_device *)disk->private_data; return sprintf(buf, "%d\n", task_pid_nr(nbd->task_recv)); }

Contributors

PersonTokensPropCommitsCommitProp
paul clementspaul clements2338.98%133.33%
kay sieverskay sievers1830.51%133.33%
markus pargmannmarkus pargmann1830.51%133.33%
Total59100.00%3100.00%

static struct device_attribute pid_attr = { .attr = { .name = "pid", .mode = S_IRUGO}, .show = pid_show, }; struct recv_thread_args { struct work_struct work; struct nbd_device *nbd; int index; };
static void recv_work(struct work_struct *work) { struct recv_thread_args *args = container_of(work, struct recv_thread_args, work); struct nbd_device *nbd = args->nbd; struct nbd_cmd *cmd; int ret = 0; BUG_ON(nbd->magic != NBD_MAGIC); while (1) { cmd = nbd_read_stat(nbd, args->index); if (IS_ERR(cmd)) { ret = PTR_ERR(cmd); break; } nbd_end_request(cmd); } /* * We got an error, shut everybody down if this wasn't the result of a * disconnect request. */ if (ret && !test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags)) sock_shutdown(nbd); atomic_dec(&nbd->recv_threads); wake_up(&nbd->recv_wq); }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik6852.31%222.22%
markus pargmannmarkus pargmann3224.62%333.33%
pre-gitpre-git1612.31%111.11%
andrew mortonandrew morton86.15%111.11%
wanlong gaowanlong gao32.31%111.11%
americo wangamerico wang32.31%111.11%
Total130100.00%9100.00%


static void nbd_clear_req(struct request *req, void *data, bool reserved) { struct nbd_cmd *cmd; if (!blk_mq_request_started(req)) return; cmd = blk_mq_rq_to_pdu(req); req->errors++; nbd_end_request(cmd); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git2857.14%350.00%
josef bacikjosef bacik1938.78%116.67%
dave jonesdave jones12.04%116.67%
adrian bunkadrian bunk12.04%116.67%
Total49100.00%6100.00%


static void nbd_clear_que(struct nbd_device *nbd) { BUG_ON(nbd->magic != NBD_MAGIC); blk_mq_tagset_busy_iter(&nbd->tag_set, nbd_clear_req, NULL); dev_dbg(disk_to_dev(nbd->disk), "queue cleared\n"); }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik1943.18%120.00%
markus pargmannmarkus pargmann1431.82%240.00%
paul clementspaul clements1022.73%120.00%
pre-gitpre-git12.27%120.00%
Total44100.00%5100.00%


static void nbd_handle_cmd(struct nbd_cmd *cmd, int index) { struct request *req = blk_mq_rq_from_pdu(cmd); struct nbd_device *nbd = cmd->nbd; struct nbd_sock *nsock; if (index >= nbd->num_connections) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Attempted send on invalid socket\n"); goto error_out; } if (test_bit(NBD_DISCONNECTED, &nbd->runtime_flags)) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Attempted send on closed socket\n"); goto error_out; } if (req->cmd_type != REQ_TYPE_FS && req->cmd_type != REQ_TYPE_DRV_PRIV) goto error_out; if (req->cmd_type == REQ_TYPE_FS && rq_data_dir(req) == WRITE && (nbd->flags & NBD_FLAG_READ_ONLY)) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Write on read-only\n"); goto error_out; } req->errors = 0; nsock = nbd->socks[index]; mutex_lock(&nsock->tx_lock); if (unlikely(!nsock->sock)) { mutex_unlock(&nsock->tx_lock); dev_err_ratelimited(disk_to_dev(nbd->disk), "Attempted send on closed socket\n"); goto error_out; } if (nbd_send_cmd(nbd, cmd, index) != 0) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Request send failed\n"); req->errors++; nbd_end_request(cmd); } mutex_unlock(&nsock->tx_lock); return; error_out: req->errors++; nbd_end_request(cmd); }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik15759.25%313.04%
pre-gitpre-git2810.57%417.39%
paul clementspaul clements249.06%313.04%
laurent vivierlaurent vivier145.28%14.35%
linus torvaldslinus torvalds114.15%28.70%
americo wangamerico wang93.40%14.35%
andrew mortonandrew morton62.26%14.35%
christoph hellwigchristoph hellwig62.26%28.70%
wanlong gaowanlong gao31.13%14.35%
al viroal viro31.13%14.35%
herbert xuherbert xu10.38%14.35%
jens axboejens axboe10.38%14.35%
ingo molnaringo molnar10.38%14.35%
pavel machekpavel machek10.38%14.35%
Total265100.00%23100.00%


static int nbd_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(bd->rq); /* * Since we look at the bio's to send the request over the network we * need to make sure the completion work doesn't mark this request done * before we are done doing our send. This keeps us from dereferencing * freed data if we have particularly fast completions (ie we get the * completion before we exit sock_xmit on the last bvec) or in the case * that the server is misbehaving (or there was an error) before we're * done sending everything over the wire. */ init_completion(&cmd->send_complete); blk_mq_start_request(bd->rq); nbd_handle_cmd(cmd, hctx->queue_num); complete(&cmd->send_complete); return BLK_MQ_RQ_QUEUE_OK; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik5483.08%240.00%
laurent vivierlaurent vivier710.77%120.00%
pre-gitpre-git46.15%240.00%
Total65100.00%5100.00%


static int nbd_add_socket(struct nbd_device *nbd, struct socket *sock) { struct nbd_sock **socks; struct nbd_sock *nsock; 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; } 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; nbd->socks = socks; mutex_init(&nsock->tx_lock); nsock->sock = sock; socks[nbd->num_connections++] = nsock; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik11775.00%150.00%
markus pargmannmarkus pargmann3925.00%150.00%
Total156100.00%2100.00%

/* 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); }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik5850.00%375.00%
markus pargmannmarkus pargmann5850.00%125.00%
Total116100.00%4100.00%


static void nbd_bdev_reset(struct block_device *bdev) { set_device_ro(bdev, false); bdev->bd_inode->i_size = 0; if (max_part > 0) { blkdev_reread_part(bdev); bdev->bd_invalidated = 1; } }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann45100.00%1100.00%
Total45100.00%1100.00%


static void nbd_parse_flags(struct nbd_device *nbd, struct block_device *bdev) { if (nbd->flags & NBD_FLAG_READ_ONLY) set_device_ro(bdev, true); if (nbd->flags & NBD_FLAG_SEND_TRIM) queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); if (nbd->flags & NBD_FLAG_SEND_FLUSH) blk_queue_write_cache(nbd->disk->queue, true, false); else blk_queue_write_cache(nbd->disk->queue, false, false); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann7790.59%150.00%
jens axboejens axboe89.41%150.00%
Total85100.00%2100.00%


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); } }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik8182.65%225.00%
pre-gitpre-git88.16%225.00%
pavel machekpavel machek55.10%112.50%
paolo bonzinipaolo bonzini22.04%112.50%
wanlong gaowanlong gao11.02%112.50%
americo wangamerico wang11.02%112.50%
Total98100.00%8100.00%

static int nbd_dev_dbg_init(struct nbd_device *nbd); static void nbd_dev_dbg_close(struct nbd_device *nbd); /* 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: { dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n"); if (!nbd->socks) return -EINVAL; mutex_unlock(&nbd->config_lock); fsync_bdev(bdev); mutex_lock(&nbd->config_lock); /* Check again after getting mutex back. */ if (!nbd->socks) return -EINVAL; if (!test_and_set_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags)) send_disconnects(nbd); return 0; } case NBD_CLEAR_SOCK: 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; nbd->task_setup = NULL; } return 0; case NBD_SET_SOCK: { int err; struct socket *sock = sockfd_lookup(arg, &err); if (!sock) return err; err = nbd_add_socket(nbd, sock); if (!err && max_part) bdev->bd_invalidated = 1; return err; } case NBD_SET_BLKSIZE: { loff_t bsize = div_s64(nbd->bytesize, arg); return nbd_size_set(nbd, bdev, arg, bsize); } case NBD_SET_SIZE: return nbd_size_set(nbd, bdev, nbd->blksize, div_s64(arg, nbd->blksize)); case NBD_SET_SIZE_BLOCKS: return nbd_size_set(nbd, bdev, nbd->blksize, arg); case NBD_SET_TIMEOUT: nbd->tag_set.timeout = arg * HZ; return 0; case NBD_SET_FLAGS: nbd->flags = arg; return 0; case NBD_DO_IT: { struct recv_thread_args *args; int num_connections = nbd->num_connections; int error = 0, i; if (nbd->task_recv) return -EBUSY; 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"); error = -EINVAL; goto out_err; } 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) { error = -ENOMEM; goto out_err; } nbd->task_recv = current; 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); 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); 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); nbd_bdev_reset(bdev); /* user requested, ignore socket errors */ if (test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags)) error = 0; if (test_bit(NBD_TIMEDOUT, &nbd->runtime_flags)) error = -ETIMEDOUT; nbd_reset(nbd); return error; } case NBD_CLEAR_QUE: /* * This is for compatibility only. The queue is always cleared * by NBD_DO_IT or NBD_CLEAR_SOCK. */ return 0; case NBD_PRINT_DEBUG: /* * For compatibility only, we no longer keep a list of * outstanding requests. */ return 0; } return -ENOTTY; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik51063.20%410.53%
markus pargmannmarkus pargmann668.18%615.79%
pre-gitpre-git607.43%37.89%
paolo bonzinipaolo bonzini323.97%25.26%
pavel machekpavel machek222.73%25.26%
al viroal viro182.23%410.53%
jens axboejens axboe182.23%25.26%
laurent vivierlaurent vivier161.98%25.26%
wanlong gaowanlong gao161.98%12.63%
paul clementspaul clements141.73%410.53%
andrew mortonandrew morton131.61%25.26%
vegard nossumvegard nossum80.99%12.63%
alan coxalan cox70.87%12.63%
arnd bergmannarnd bergmann30.37%12.63%
alex blighalex bligh20.25%12.63%
herbert xuherbert xu10.12%12.63%
americo wangamerico wang10.12%12.63%
Total807100.00%38100.00%


static int nbd_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { struct nbd_device *nbd = bdev->bd_disk->private_data; int error; if (!capable(CAP_SYS_ADMIN)) return -EPERM; BUG_ON(nbd->magic != NBD_MAGIC); mutex_lock(&nbd->config_lock); error = __nbd_ioctl(bdev, nbd, cmd, arg); mutex_unlock(&nbd->config_lock); return error; }

Contributors

PersonTokensPropCommitsCommitProp
pavel machekpavel machek7685.39%120.00%
wanlong gaowanlong gao66.74%120.00%
arnd bergmannarnd bergmann33.37%120.00%
pre-gitpre-git22.25%120.00%
josef bacikjosef bacik22.25%120.00%
Total89100.00%5100.00%

static const struct block_device_operations nbd_fops = { .owner = THIS_MODULE, .ioctl = nbd_ioctl, .compat_ioctl = nbd_ioctl, }; #if IS_ENABLED(CONFIG_DEBUG_FS)
static int nbd_dbg_tasks_show(struct seq_file *s, void *unused) { struct nbd_device *nbd = s->private; if (nbd->task_recv) seq_printf(s, "recv: %d\n", task_pid_nr(nbd->task_recv)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann3165.96%112.50%
pre-gitpre-git919.15%225.00%
sven wegenersven wegener36.38%112.50%
laurent vivierlaurent vivier12.13%112.50%
linus torvaldslinus torvalds12.13%112.50%
al viroal viro12.13%112.50%
adrian bunkadrian bunk12.13%112.50%
Total47100.00%8100.00%


static int nbd_dbg_tasks_open(struct inode *inode, struct file *file) { return single_open(file, nbd_dbg_tasks_show, inode->i_private); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann2796.43%150.00%
namhyung kimnamhyung kim13.57%150.00%
Total28100.00%2100.00%

static const struct file_operations nbd_dbg_tasks_ops = { .open = nbd_dbg_tasks_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, };
static int nbd_dbg_flags_show(struct seq_file *s, void *unused) { struct nbd_device *nbd = s->private; u32 flags = nbd->flags; seq_printf(s, "Hex: 0x%08x\n\n", flags); seq_puts(s, "Known flags:\n"); if (flags & NBD_FLAG_HAS_FLAGS) seq_puts(s, "NBD_FLAG_HAS_FLAGS\n"); if (flags & NBD_FLAG_READ_ONLY) seq_puts(s, "NBD_FLAG_READ_ONLY\n"); if (flags & NBD_FLAG_SEND_FLUSH) seq_puts(s, "NBD_FLAG_SEND_FLUSH\n"); if (flags & NBD_FLAG_SEND_TRIM) seq_puts(s, "NBD_FLAG_SEND_TRIM\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann8987.25%120.00%
sudip mukherjeesudip mukherjee65.88%120.00%
namhyung kimnamhyung kim43.92%240.00%
laurent vivierlaurent vivier32.94%120.00%
Total102100.00%5100.00%


static int nbd_dbg_flags_open(struct inode *inode, struct file *file) { return single_open(file, nbd_dbg_flags_show, inode->i_private); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann28100.00%1100.00%
Total28100.00%1100.00%

static const struct file_operations nbd_dbg_flags_ops = { .open = nbd_dbg_flags_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, };
static int nbd_dev_dbg_init(struct nbd_device *nbd) { struct dentry *dir; if (!nbd_dbg_dir) return -EIO; dir = debugfs_create_dir(nbd_name(nbd), nbd_dbg_dir); if (!dir) { dev_err(nbd_to_dev(nbd), "Failed to create debugfs dir for '%s'\n", nbd_name(nbd)); return -EIO; } nbd->dbg_dir = dir; debugfs_create_file("tasks", 0444, dir, nbd, &nbd_dbg_tasks_ops); debugfs_create_u64("size_bytes", 0444, dir, &nbd->bytesize); debugfs_create_u32("timeout", 0444, dir, &nbd->tag_set.timeout); debugfs_create_u64("blocksize", 0444, dir, &nbd->blksize); debugfs_create_file("flags", 0444, dir, nbd, &nbd_dbg_flags_ops); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann14097.22%250.00%
josef bacikjosef bacik42.78%250.00%
Total144100.00%4100.00%


static void nbd_dev_dbg_close(struct nbd_device *nbd) { debugfs_remove_recursive(nbd->dbg_dir); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann18100.00%1100.00%
Total18100.00%1100.00%


static int nbd_dbg_init(void) { struct dentry *dbg_dir; dbg_dir = debugfs_create_dir("nbd", NULL); if (!dbg_dir) return -EIO; nbd_dbg_dir = dbg_dir; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann38100.00%2100.00%
Total38100.00%2100.00%


static void nbd_dbg_close(void) { debugfs_remove_recursive(nbd_dbg_dir); }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann13100.00%1100.00%
Total13100.00%1100.00%

#else /* IS_ENABLED(CONFIG_DEBUG_FS) */
static int nbd_dev_dbg_init(struct nbd_device *nbd) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann14100.00%1100.00%
Total14100.00%1100.00%


static void nbd_dev_dbg_close(struct nbd_device *nbd) { }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann10100.00%1100.00%
Total10100.00%1100.00%


static int nbd_dbg_init(void) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann11100.00%1100.00%
Total11100.00%1100.00%


static void nbd_dbg_close(void) { }

Contributors

PersonTokensPropCommitsCommitProp
markus pargmannmarkus pargmann7100.00%1100.00%
Total7100.00%1100.00%

#endif
static int nbd_init_request(void *data, struct request *rq, unsigned int hctx_idx, unsigned int request_idx, unsigned int numa_node) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(rq); cmd->nbd = data; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik46100.00%1100.00%
Total46100.00%1100.00%

static struct blk_mq_ops nbd_mq_ops = { .queue_rq = nbd_queue_rq, .init_request = nbd_init_request, .timeout = nbd_xmit_timeout, }; /* * And here should be modules and kernel interface * (Just smiley confuses emacs :-) */
static int __init nbd_init(void) { int err = -ENOMEM; int i; int part_shift; BUILD_BUG_ON(sizeof(struct nbd_request) != 28); if (max_part < 0) { printk(KERN_ERR "nbd: max_part must be >= 0\n"); return -EINVAL; } part_shift = 0; if (max_part > 0) { part_shift = fls(max_part); /* * Adjust max_part according to part_shift as it is exported * to user space so that user can know the max number of * partition kernel should be able to manage. * * Note that -1 is required because partition 0 is reserved * for the whole disk. */ max_part = (1UL << part_shift) - 1; } if ((1UL << part_shift) > DISK_MAX_PARTS) return -EINVAL; if (nbds_max > 1UL << (MINORBITS - part_shift)) return -EINVAL; nbd_dev = kcalloc(nbds_max, sizeof(*nbd_dev), GFP_KERNEL); if (!nbd_dev) return -ENOMEM; for (i = 0; i < nbds_max; i++) { struct request_queue *q; struct gendisk *disk = alloc_disk(1 << part_shift); if (!disk) goto out; nbd_dev[i].disk = disk; nbd_dev[i].tag_set.ops = &nbd_mq_ops; nbd_dev[i].tag_set.nr_hw_queues = 1; nbd_dev[i].tag_set.queue_depth = 128; nbd_dev[i].tag_set.numa_node = NUMA_NO_NODE; nbd_dev[i].tag_set.cmd_size = sizeof(struct nbd_cmd); nbd_dev[i].tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE | BLK_MQ_F_BLOCKING; nbd_dev[i].tag_set.driver_data = &nbd_dev[i]; err = blk_mq_alloc_tag_set(&nbd_dev[i].tag_set); if (err) { put_disk(disk); goto out; } /* * The new linux 2.5 block layer implementation requires * every gendisk to have its very own request_queue struct. * These structs are big so we dynamically allocate them. */ q = blk_mq_init_queue(&nbd_dev[i].tag_set); if (IS_ERR(q)) { blk_mq_free_tag_set(&nbd_dev[i].tag_set); put_disk(disk); goto out; } disk->queue = q; /* * Tell the block layer that we are not a rotational device */ queue_flag_set_unlocked(QUEUE_FLAG_NONROT, disk->queue); queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, disk->queue); disk->queue->limits.discard_granularity = 512; blk_queue_max_discard_sectors(disk->queue, UINT_MAX); disk->queue->limits.discard_zeroes_data = 0; blk_queue_max_hw_sectors(disk->queue, 65536); disk->queue->limits.max_sectors = 256; } if (register_blkdev(NBD_MAJOR, "nbd")) { err = -EIO; goto out; } printk(KERN_INFO "nbd: registered device at major %d\n", NBD_MAJOR); nbd_dbg_init(); for (i = 0; i < nbds_max; i++) { struct gendisk *disk = nbd_dev[i].disk; nbd_dev[i].magic = NBD_MAGIC; 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); } return 0; out: while (i--) { blk_mq_free_tag_set(&nbd_dev[i].tag_set); blk_cleanup_queue(nbd_dev[i].disk->queue); put_disk(nbd_dev[i].disk); } kfree(nbd_dev); return err; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik15825.82%38.57%
markus pargmannmarkus pargmann13722.39%25.71%
al viroal viro11418.63%617.14%
pre-gitpre-git609.80%617.14%
paul clementspaul clements335.39%25.71%
lou langholtzlou langholtz315.07%12.86%
michal belczykmichal belczyk193.10%12.86%
jeff moyerjeff moyer162.61%12.86%
jens axboejens axboe91.47%38.57%
mike snitzermike snitzer91.47%12.86%
christoph hellwigchristoph hellwig71.14%25.71%
sudip mukherjeesudip mukherjee50.82%12.86%
sven wegenersven wegener50.82%12.86%
laurent vivierlaurent vivier40.65%12.86%
lars marowsky-breelars marowsky-bree20.33%12.86%
ingo molnaringo molnar10.16%12.86%
wanlong gaowanlong gao10.16%12.86%
andrew mortonandrew morton10.16%12.86%
Total612100.00%35100.00%


static void __exit nbd_cleanup(void) { int i; nbd_dbg_close(); for (i = 0; i < nbds_max; i++) { struct gendisk *disk = nbd_dev[i].disk; nbd_dev[i].magic = 0; if (disk) { del_gendisk(disk); blk_cleanup_queue(disk->queue); blk_mq_free_tag_set(&nbd_dev[i].tag_set); put_disk(disk); } } unregister_blkdev(NBD_MAJOR, "nbd"); kfree(nbd_dev); printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR); }

Contributors

PersonTokensPropCommitsCommitProp
lou langholtzlou langholtz2725.71%17.14%
al viroal viro2422.86%214.29%
pre-gitpre-git1615.24%321.43%
josef bacikjosef bacik1110.48%17.14%
lars marowsky-breelars marowsky-bree109.52%17.14%
andrew mortonandrew morton54.76%214.29%
sven wegenersven wegener54.76%17.14%
linus torvaldslinus torvalds32.86%17.14%
markus pargmannmarkus pargmann32.86%17.14%
christoph hellwigchristoph hellwig10.95%17.14%
Total105100.00%14100.00%

module_init(nbd_init); module_exit(nbd_cleanup); MODULE_DESCRIPTION("Network Block Device"); MODULE_LICENSE("GPL"); module_param(nbds_max, int, 0444); MODULE_PARM_DESC(nbds_max, "number of network block devices to initialize (default: 16)"); module_param(max_part, int, 0444); MODULE_PARM_DESC(max_part, "number of partitions per device (default: 0)");

Overall Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik177732.68%106.71%
markus pargmannmarkus pargmann135524.92%1912.75%
pre-gitpre-git61911.38%1711.41%
andrew mortonandrew morton2003.68%74.70%
lou langholtzlou langholtz1853.40%10.67%
paul clementspaul clements1813.33%106.71%
al viroal viro1783.27%117.38%
pavel machekpavel machek1051.93%42.68%
linus torvaldslinus torvalds881.62%96.04%
christoph hellwigchristoph hellwig851.56%42.68%
jens axboejens axboe841.54%85.37%
laurent vivierlaurent vivier701.29%21.34%
wanlong gaowanlong gao591.08%10.67%
americo wangamerico wang510.94%32.01%
michal feixmichal feix380.70%21.34%
mike snitzermike snitzer360.66%21.34%
paolo bonzinipaolo bonzini340.63%21.34%
lars marowsky-breelars marowsky-bree340.63%10.67%
mel gormanmel gorman250.46%10.67%
herbert xuherbert xu200.37%10.67%
kay sieverskay sievers190.35%10.67%
michal belczykmichal belczyk190.35%10.67%
jeff moyerjeff moyer160.29%10.67%
tejun heotejun heo150.28%32.01%
alex blighalex bligh140.26%10.67%
hani benhabileshani benhabiles140.26%10.67%
sven wegenersven wegener130.24%10.67%
neil brownneil brown120.22%10.67%
sudip mukherjeesudip mukherjee110.20%10.67%
michael christiemichael christie100.18%21.34%
arnd bergmannarnd bergmann100.18%32.01%
vegard nossumvegard nossum80.15%10.67%
namhyung kimnamhyung kim80.15%32.01%
dave jonesdave jones80.15%10.67%
alan coxalan cox70.13%10.67%
kiyoshi uedakiyoshi ueda70.13%10.67%
kent overstreetkent overstreet50.09%21.34%
rusty russellrusty russell40.07%10.67%
trond myklebusttrond myklebust30.06%10.67%
arnaldo carvalho de meloarnaldo carvalho de melo30.06%10.67%
adrian bunkadrian bunk30.06%21.34%
ingo molnaringo molnar20.04%10.67%
david s. millerdavid s. miller20.04%21.34%
alexey dobriyanalexey dobriyan10.02%10.67%
Total5438100.00%149100.00%
Directory: drivers/block
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.