diff options
Diffstat (limited to 'drivers/block/nbd.c')
| -rw-r--r-- | drivers/block/nbd.c | 566 |
1 files changed, 332 insertions, 234 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 8299e2d3b61..fb31b8ee437 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -4,7 +4,7 @@ * 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 Pavel Machek <pavel@ucw.cz> + * 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. @@ -24,20 +24,21 @@ #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 <asm/uaccess.h> -#include <asm/system.h> #include <asm/types.h> #include <linux/nbd.h> -#define LO_MAGIC 0x68797548 +#define NBD_MAGIC 0x68797548 #ifdef NDEBUG #define dprintk(flags, fmt...) @@ -77,6 +78,8 @@ static const char *ioctl_cmd_to_ascii(int cmd) case NBD_SET_SOCK: return "set-sock"; case NBD_SET_BLKSIZE: return "set-blksize"; case NBD_SET_SIZE: return "set-size"; + case NBD_SET_TIMEOUT: return "set-timeout"; + case NBD_SET_FLAGS: return "set-flags"; case NBD_DO_IT: return "do-it"; case NBD_CLEAR_SOCK: return "clear-sock"; case NBD_CLEAR_QUE: return "clear-que"; @@ -95,6 +98,8 @@ static const char *nbdcmd_to_ascii(int 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"; } @@ -110,11 +115,11 @@ static void nbd_end_request(struct request *req) req, error ? "failed" : "done"); spin_lock_irqsave(q->queue_lock, flags); - __blk_end_request(req, error, req->nr_sectors << 9); + __blk_end_request_all(req, error); spin_unlock_irqrestore(q->queue_lock, flags); } -static void sock_shutdown(struct nbd_device *lo, int lock) +static void sock_shutdown(struct nbd_device *nbd, int lock) { /* Forcibly shutdown the socket causing all listeners * to error @@ -123,15 +128,14 @@ static void sock_shutdown(struct nbd_device *lo, int lock) * there should be a more generic interface rather than * calling socket ops directly here */ if (lock) - mutex_lock(&lo->tx_lock); - if (lo->sock) { - printk(KERN_WARNING "%s: shutting down socket\n", - lo->disk->disk_name); - kernel_sock_shutdown(lo->sock, SHUT_RDWR); - lo->sock = NULL; + mutex_lock(&nbd->tx_lock); + if (nbd->sock) { + dev_warn(disk_to_dev(nbd->disk), "shutting down socket\n"); + kernel_sock_shutdown(nbd->sock, SHUT_RDWR); + nbd->sock = NULL; } if (lock) - mutex_unlock(&lo->tx_lock); + mutex_unlock(&nbd->tx_lock); } static void nbd_xmit_timeout(unsigned long arg) @@ -146,18 +150,20 @@ static void nbd_xmit_timeout(unsigned long arg) /* * Send or receive packet. */ -static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, +static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size, int msg_flags) { - struct socket *sock = lo->sock; + struct socket *sock = nbd->sock; int result; struct msghdr msg; struct kvec iov; sigset_t blocked, oldset; + unsigned long pflags = current->flags; if (unlikely(!sock)) { - printk(KERN_ERR "%s: Attempted %s on closed socket in sock_xmit\n", - lo->disk->disk_name, (send ? "send" : "recv")); + dev_err(disk_to_dev(nbd->disk), + "Attempted %s on closed socket in sock_xmit\n", + (send ? "send" : "recv")); return -EINVAL; } @@ -166,8 +172,9 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, siginitsetinv(&blocked, sigmask(SIGKILL)); sigprocmask(SIG_SETMASK, &blocked, &oldset); + current->flags |= PF_MEMALLOC; do { - sock->sk->sk_allocation = GFP_NOIO; + sock->sk->sk_allocation = GFP_NOIO | __GFP_MEMALLOC; iov.iov_base = buf; iov.iov_len = size; msg.msg_name = NULL; @@ -179,18 +186,19 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, if (send) { struct timer_list ti; - if (lo->xmit_timeout) { + if (nbd->xmit_timeout) { init_timer(&ti); ti.function = nbd_xmit_timeout; ti.data = (unsigned long)current; - ti.expires = jiffies + lo->xmit_timeout; + ti.expires = jiffies + nbd->xmit_timeout; add_timer(&ti); } result = kernel_sendmsg(sock, &msg, &iov, 1, size); - if (lo->xmit_timeout) + if (nbd->xmit_timeout) del_timer_sync(&ti); } else - result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0); + result = kernel_recvmsg(sock, &msg, &iov, 1, size, + msg.msg_flags); if (signal_pending(current)) { siginfo_t info; @@ -198,7 +206,7 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, task_pid_nr(current), current->comm, dequeue_signal_lock(current, ¤t->blocked, &info)); result = -EINTR; - sock_shutdown(lo, !send); + sock_shutdown(nbd, !send); break; } @@ -212,63 +220,70 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, } while (size > 0); sigprocmask(SIG_SETMASK, &oldset, NULL); + tsk_restore_flags(current, pflags, PF_MEMALLOC); return result; } -static inline int sock_send_bvec(struct nbd_device *lo, struct bio_vec *bvec, +static inline int sock_send_bvec(struct nbd_device *nbd, struct bio_vec *bvec, int flags) { int result; void *kaddr = kmap(bvec->bv_page); - result = sock_xmit(lo, 1, kaddr + bvec->bv_offset, bvec->bv_len, flags); + result = sock_xmit(nbd, 1, kaddr + bvec->bv_offset, + bvec->bv_len, flags); kunmap(bvec->bv_page); return result; } /* always call with the tx_lock held */ -static int nbd_send_req(struct nbd_device *lo, struct request *req) +static int nbd_send_req(struct nbd_device *nbd, struct request *req) { int result, flags; struct nbd_request request; - unsigned long size = req->nr_sectors << 9; + unsigned long size = blk_rq_bytes(req); + memset(&request, 0, sizeof(request)); request.magic = htonl(NBD_REQUEST_MAGIC); request.type = htonl(nbd_cmd(req)); - request.from = cpu_to_be64((u64) req->sector << 9); - request.len = htonl(size); + + if (nbd_cmd(req) != NBD_CMD_FLUSH && nbd_cmd(req) != NBD_CMD_DISC) { + request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9); + request.len = htonl(size); + } memcpy(request.handle, &req, sizeof(req)); - dprintk(DBG_TX, "%s: request %p: sending control (%s@%llu,%luB)\n", - lo->disk->disk_name, req, + dprintk(DBG_TX, "%s: request %p: sending control (%s@%llu,%uB)\n", + nbd->disk->disk_name, req, nbdcmd_to_ascii(nbd_cmd(req)), - (unsigned long long)req->sector << 9, - req->nr_sectors << 9); - result = sock_xmit(lo, 1, &request, sizeof(request), + (unsigned long long)blk_rq_pos(req) << 9, + blk_rq_bytes(req)); + result = sock_xmit(nbd, 1, &request, sizeof(request), (nbd_cmd(req) == NBD_CMD_WRITE) ? MSG_MORE : 0); if (result <= 0) { - printk(KERN_ERR "%s: Send control failed (result %d)\n", - lo->disk->disk_name, result); + dev_err(disk_to_dev(nbd->disk), + "Send control failed (result %d)\n", result); goto error_out; } if (nbd_cmd(req) == NBD_CMD_WRITE) { struct req_iterator iter; - struct bio_vec *bvec; + struct bio_vec bvec; /* * we are really probing at internals to determine * whether to set MSG_MORE or not... */ rq_for_each_segment(bvec, req, iter) { flags = 0; - if (!rq_iter_last(req, iter)) + if (!rq_iter_last(bvec, iter)) flags = MSG_MORE; dprintk(DBG_TX, "%s: request %p: sending %d bytes data\n", - lo->disk->disk_name, req, bvec->bv_len); - result = sock_send_bvec(lo, bvec, flags); + nbd->disk->disk_name, req, bvec.bv_len); + result = sock_send_bvec(nbd, &bvec, flags); if (result <= 0) { - printk(KERN_ERR "%s: Send data failed (result %d)\n", - lo->disk->disk_name, result); + dev_err(disk_to_dev(nbd->disk), + "Send data failed (result %d)\n", + result); goto error_out; } } @@ -276,28 +291,28 @@ static int nbd_send_req(struct nbd_device *lo, struct request *req) return 0; error_out: - return 1; + return -EIO; } -static struct request *nbd_find_request(struct nbd_device *lo, +static struct request *nbd_find_request(struct nbd_device *nbd, struct request *xreq) { struct request *req, *tmp; int err; - err = wait_event_interruptible(lo->active_wq, lo->active_req != xreq); + err = wait_event_interruptible(nbd->active_wq, nbd->active_req != xreq); if (unlikely(err)) goto out; - spin_lock(&lo->queue_lock); - list_for_each_entry_safe(req, tmp, &lo->queue_head, queuelist) { + spin_lock(&nbd->queue_lock); + list_for_each_entry_safe(req, tmp, &nbd->queue_head, queuelist) { if (req != xreq) continue; list_del_init(&req->queuelist); - spin_unlock(&lo->queue_lock); + spin_unlock(&nbd->queue_lock); return req; } - spin_unlock(&lo->queue_lock); + spin_unlock(&nbd->queue_lock); err = -ENOENT; @@ -305,79 +320,78 @@ out: return ERR_PTR(err); } -static inline int sock_recv_bvec(struct nbd_device *lo, struct bio_vec *bvec) +static inline int sock_recv_bvec(struct nbd_device *nbd, struct bio_vec *bvec) { int result; void *kaddr = kmap(bvec->bv_page); - result = sock_xmit(lo, 0, kaddr + bvec->bv_offset, bvec->bv_len, + result = sock_xmit(nbd, 0, kaddr + bvec->bv_offset, bvec->bv_len, MSG_WAITALL); kunmap(bvec->bv_page); return result; } /* NULL returned = something went wrong, inform userspace */ -static struct request *nbd_read_stat(struct nbd_device *lo) +static struct request *nbd_read_stat(struct nbd_device *nbd) { int result; struct nbd_reply reply; struct request *req; reply.magic = 0; - result = sock_xmit(lo, 0, &reply, sizeof(reply), MSG_WAITALL); + result = sock_xmit(nbd, 0, &reply, sizeof(reply), MSG_WAITALL); if (result <= 0) { - printk(KERN_ERR "%s: Receive control failed (result %d)\n", - lo->disk->disk_name, result); + dev_err(disk_to_dev(nbd->disk), + "Receive control failed (result %d)\n", result); goto harderror; } if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { - printk(KERN_ERR "%s: Wrong magic (0x%lx)\n", - lo->disk->disk_name, + dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n", (unsigned long)ntohl(reply.magic)); result = -EPROTO; goto harderror; } - req = nbd_find_request(lo, *(struct request **)reply.handle); + req = nbd_find_request(nbd, *(struct request **)reply.handle); if (IS_ERR(req)) { result = PTR_ERR(req); if (result != -ENOENT) goto harderror; - printk(KERN_ERR "%s: Unexpected reply (%p)\n", - lo->disk->disk_name, reply.handle); + dev_err(disk_to_dev(nbd->disk), "Unexpected reply (%p)\n", + reply.handle); result = -EBADR; goto harderror; } if (ntohl(reply.error)) { - printk(KERN_ERR "%s: Other side returned error (%d)\n", - lo->disk->disk_name, ntohl(reply.error)); + dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n", + ntohl(reply.error)); req->errors++; return req; } dprintk(DBG_RX, "%s: request %p: got reply\n", - lo->disk->disk_name, req); + nbd->disk->disk_name, req); if (nbd_cmd(req) == NBD_CMD_READ) { struct req_iterator iter; - struct bio_vec *bvec; + struct bio_vec bvec; rq_for_each_segment(bvec, req, iter) { - result = sock_recv_bvec(lo, bvec); + result = sock_recv_bvec(nbd, &bvec); if (result <= 0) { - printk(KERN_ERR "%s: Receive data failed (result %d)\n", - lo->disk->disk_name, result); + dev_err(disk_to_dev(nbd->disk), "Receive data failed (result %d)\n", + result); req->errors++; return req; } dprintk(DBG_RX, "%s: request %p: got %d bytes data\n", - lo->disk->disk_name, req, bvec->bv_len); + nbd->disk->disk_name, req, bvec.bv_len); } } return req; harderror: - lo->harderror = result; + nbd->harderror = result; return NULL; } @@ -395,48 +409,57 @@ static struct device_attribute pid_attr = { .show = pid_show, }; -static int nbd_do_it(struct nbd_device *lo) +static int nbd_do_it(struct nbd_device *nbd) { struct request *req; int ret; - BUG_ON(lo->magic != LO_MAGIC); + BUG_ON(nbd->magic != NBD_MAGIC); - lo->pid = current->pid; - ret = sysfs_create_file(&disk_to_dev(lo->disk)->kobj, &pid_attr.attr); + sk_set_memalloc(nbd->sock->sk); + nbd->pid = task_pid_nr(current); + ret = device_create_file(disk_to_dev(nbd->disk), &pid_attr); if (ret) { - printk(KERN_ERR "nbd: sysfs_create_file failed!"); - lo->pid = 0; + dev_err(disk_to_dev(nbd->disk), "device_create_file failed!\n"); + nbd->pid = 0; return ret; } - while ((req = nbd_read_stat(lo)) != NULL) + while ((req = nbd_read_stat(nbd)) != NULL) nbd_end_request(req); - sysfs_remove_file(&disk_to_dev(lo->disk)->kobj, &pid_attr.attr); - lo->pid = 0; + device_remove_file(disk_to_dev(nbd->disk), &pid_attr); + nbd->pid = 0; return 0; } -static void nbd_clear_que(struct nbd_device *lo) +static void nbd_clear_que(struct nbd_device *nbd) { struct request *req; - BUG_ON(lo->magic != LO_MAGIC); + BUG_ON(nbd->magic != NBD_MAGIC); /* - * Because we have set lo->sock to NULL under the tx_lock, all + * Because we have set nbd->sock to NULL under the tx_lock, all * modifications to the list must have completed by now. For * the same reason, the active_req must be NULL. * * As a consequence, we don't need to take the spin lock while * purging the list here. */ - BUG_ON(lo->sock); - BUG_ON(lo->active_req); + BUG_ON(nbd->sock); + BUG_ON(nbd->active_req); + + while (!list_empty(&nbd->queue_head)) { + req = list_entry(nbd->queue_head.next, struct request, + queuelist); + list_del_init(&req->queuelist); + req->errors++; + nbd_end_request(req); + } - while (!list_empty(&lo->queue_head)) { - req = list_entry(lo->queue_head.next, struct request, + while (!list_empty(&nbd->waiting_queue)) { + req = list_entry(nbd->waiting_queue.next, struct request, queuelist); list_del_init(&req->queuelist); req->errors++; @@ -445,49 +468,55 @@ static void nbd_clear_que(struct nbd_device *lo) } -static void nbd_handle_req(struct nbd_device *lo, struct request *req) +static void nbd_handle_req(struct nbd_device *nbd, struct request *req) { - if (!blk_fs_request(req)) + if (req->cmd_type != REQ_TYPE_FS) goto error_out; nbd_cmd(req) = NBD_CMD_READ; if (rq_data_dir(req) == WRITE) { - nbd_cmd(req) = NBD_CMD_WRITE; - if (lo->flags & NBD_READ_ONLY) { - printk(KERN_ERR "%s: Write on read-only\n", - lo->disk->disk_name); + if ((req->cmd_flags & REQ_DISCARD)) { + WARN_ON(!(nbd->flags & NBD_FLAG_SEND_TRIM)); + nbd_cmd(req) = NBD_CMD_TRIM; + } else + nbd_cmd(req) = NBD_CMD_WRITE; + if (nbd->flags & NBD_FLAG_READ_ONLY) { + dev_err(disk_to_dev(nbd->disk), + "Write on read-only\n"); goto error_out; } } + if (req->cmd_flags & REQ_FLUSH) { + BUG_ON(unlikely(blk_rq_sectors(req))); + nbd_cmd(req) = NBD_CMD_FLUSH; + } + req->errors = 0; - mutex_lock(&lo->tx_lock); - if (unlikely(!lo->sock)) { - mutex_unlock(&lo->tx_lock); - printk(KERN_ERR "%s: Attempted send on closed socket\n", - lo->disk->disk_name); - req->errors++; - nbd_end_request(req); - return; + mutex_lock(&nbd->tx_lock); + if (unlikely(!nbd->sock)) { + mutex_unlock(&nbd->tx_lock); + dev_err(disk_to_dev(nbd->disk), + "Attempted send on closed socket\n"); + goto error_out; } - lo->active_req = req; + nbd->active_req = req; - if (nbd_send_req(lo, req) != 0) { - printk(KERN_ERR "%s: Request send failed\n", - lo->disk->disk_name); + if (nbd_send_req(nbd, req) != 0) { + dev_err(disk_to_dev(nbd->disk), "Request send failed\n"); req->errors++; nbd_end_request(req); } else { - spin_lock(&lo->queue_lock); - list_add(&req->queuelist, &lo->queue_head); - spin_unlock(&lo->queue_lock); + spin_lock(&nbd->queue_lock); + list_add_tail(&req->queuelist, &nbd->queue_head); + spin_unlock(&nbd->queue_lock); } - lo->active_req = NULL; - mutex_unlock(&lo->tx_lock); - wake_up_all(&lo->active_wq); + nbd->active_req = NULL; + mutex_unlock(&nbd->tx_lock); + wake_up_all(&nbd->active_wq); return; @@ -498,28 +527,28 @@ error_out: static int nbd_thread(void *data) { - struct nbd_device *lo = data; + struct nbd_device *nbd = data; struct request *req; - set_user_nice(current, -20); - while (!kthread_should_stop() || !list_empty(&lo->waiting_queue)) { + set_user_nice(current, MIN_NICE); + while (!kthread_should_stop() || !list_empty(&nbd->waiting_queue)) { /* wait for something to do */ - wait_event_interruptible(lo->waiting_wq, + wait_event_interruptible(nbd->waiting_wq, kthread_should_stop() || - !list_empty(&lo->waiting_queue)); + !list_empty(&nbd->waiting_queue)); /* extract request */ - if (list_empty(&lo->waiting_queue)) + if (list_empty(&nbd->waiting_queue)) continue; - spin_lock_irq(&lo->queue_lock); - req = list_entry(lo->waiting_queue.next, struct request, + spin_lock_irq(&nbd->queue_lock); + req = list_entry(nbd->waiting_queue.next, struct request, queuelist); list_del_init(&req->queuelist); - spin_unlock_irq(&lo->queue_lock); + spin_unlock_irq(&nbd->queue_lock); /* handle request */ - nbd_handle_req(lo, req); + nbd_handle_req(nbd, req); } return 0; } @@ -527,184 +556,233 @@ static int nbd_thread(void *data) /* * We always wait for result of write, for now. It would be nice to make it optional * in future - * if ((rq_data_dir(req) == WRITE) && (lo->flags & NBD_WRITE_NOCHK)) + * if ((rq_data_dir(req) == WRITE) && (nbd->flags & NBD_WRITE_NOCHK)) * { printk( "Warning: Ignoring result!\n"); nbd_end_request( req ); } */ -static void do_nbd_request(struct request_queue * q) +static void do_nbd_request(struct request_queue *q) + __releases(q->queue_lock) __acquires(q->queue_lock) { struct request *req; - while ((req = elv_next_request(q)) != NULL) { - struct nbd_device *lo; - - blkdev_dequeue_request(req); + while ((req = blk_fetch_request(q)) != NULL) { + struct nbd_device *nbd; spin_unlock_irq(q->queue_lock); dprintk(DBG_BLKDEV, "%s: request %p: dequeued (flags=%x)\n", req->rq_disk->disk_name, req, req->cmd_type); - lo = req->rq_disk->private_data; + nbd = req->rq_disk->private_data; - BUG_ON(lo->magic != LO_MAGIC); + BUG_ON(nbd->magic != NBD_MAGIC); - if (unlikely(!lo->sock)) { - printk(KERN_ERR "%s: Attempted send on closed socket\n", - lo->disk->disk_name); + if (unlikely(!nbd->sock)) { + dev_err(disk_to_dev(nbd->disk), + "Attempted send on closed socket\n"); req->errors++; nbd_end_request(req); spin_lock_irq(q->queue_lock); continue; } - spin_lock_irq(&lo->queue_lock); - list_add_tail(&req->queuelist, &lo->waiting_queue); - spin_unlock_irq(&lo->queue_lock); + spin_lock_irq(&nbd->queue_lock); + list_add_tail(&req->queuelist, &nbd->waiting_queue); + spin_unlock_irq(&nbd->queue_lock); - wake_up(&lo->waiting_wq); + wake_up(&nbd->waiting_wq); spin_lock_irq(q->queue_lock); } } -static int nbd_ioctl(struct block_device *bdev, fmode_t mode, - unsigned int cmd, unsigned long arg) -{ - struct nbd_device *lo = bdev->bd_disk->private_data; - struct file *file; - int error; - struct request sreq ; - struct task_struct *thread; +/* Must be called with tx_lock held */ - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - - BUG_ON(lo->magic != LO_MAGIC); +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; - /* Anyone capable of this syscall can do *real bad* things */ - dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n", - lo->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg); + dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n"); + if (!nbd->sock) + return -EINVAL; - switch (cmd) { - case NBD_DISCONNECT: - printk(KERN_INFO "%s: NBD_DISCONNECT\n", lo->disk->disk_name); + mutex_unlock(&nbd->tx_lock); + fsync_bdev(bdev); + mutex_lock(&nbd->tx_lock); blk_rq_init(NULL, &sreq); sreq.cmd_type = REQ_TYPE_SPECIAL; nbd_cmd(&sreq) = NBD_CMD_DISC; - /* - * Set these to sane values in case server implementation - * fails to check the request type first and also to keep - * debugging output cleaner. - */ - sreq.sector = 0; - sreq.nr_sectors = 0; - if (!lo->sock) + + /* Check again after getting mutex back. */ + if (!nbd->sock) return -EINVAL; - mutex_lock(&lo->tx_lock); - nbd_send_req(lo, &sreq); - mutex_unlock(&lo->tx_lock); - return 0; + + nbd->disconnect = 1; + + nbd_send_req(nbd, &sreq); + return 0; + } - case NBD_CLEAR_SOCK: - error = 0; - mutex_lock(&lo->tx_lock); - lo->sock = NULL; - mutex_unlock(&lo->tx_lock); - file = lo->file; - lo->file = NULL; - nbd_clear_que(lo); - BUG_ON(!list_empty(&lo->queue_head)); - if (file) - fput(file); - return error; - case NBD_SET_SOCK: - if (lo->file) + case NBD_CLEAR_SOCK: { + struct socket *sock = nbd->sock; + nbd->sock = NULL; + nbd_clear_que(nbd); + BUG_ON(!list_empty(&nbd->queue_head)); + BUG_ON(!list_empty(&nbd->waiting_queue)); + kill_bdev(bdev); + if (sock) + sockfd_put(sock); + return 0; + } + + case NBD_SET_SOCK: { + struct socket *sock; + int err; + if (nbd->sock) return -EBUSY; - error = -EINVAL; - file = fget(arg); - if (file) { - struct inode *inode = file->f_path.dentry->d_inode; - if (S_ISSOCK(inode->i_mode)) { - lo->file = file; - lo->sock = SOCKET_I(inode); - if (max_part > 0) - bdev->bd_invalidated = 1; - error = 0; - } else { - fput(file); - } + sock = sockfd_lookup(arg, &err); + if (sock) { + nbd->sock = sock; + if (max_part > 0) + bdev->bd_invalidated = 1; + nbd->disconnect = 0; /* we're connected now */ + return 0; } - return error; + return -EINVAL; + } + case NBD_SET_BLKSIZE: - lo->blksize = arg; - lo->bytesize &= ~(lo->blksize-1); - bdev->bd_inode->i_size = lo->bytesize; - set_blocksize(bdev, lo->blksize); - set_capacity(lo->disk, lo->bytesize >> 9); + nbd->blksize = arg; + nbd->bytesize &= ~(nbd->blksize-1); + bdev->bd_inode->i_size = nbd->bytesize; + set_blocksize(bdev, nbd->blksize); + set_capacity(nbd->disk, nbd->bytesize >> 9); return 0; + case NBD_SET_SIZE: - lo->bytesize = arg & ~(lo->blksize-1); - bdev->bd_inode->i_size = lo->bytesize; - set_blocksize(bdev, lo->blksize); - set_capacity(lo->disk, lo->bytesize >> 9); + nbd->bytesize = arg & ~(nbd->blksize-1); + bdev->bd_inode->i_size = nbd->bytesize; + set_blocksize(bdev, nbd->blksize); + set_capacity(nbd->disk, nbd->bytesize >> 9); return 0; + case NBD_SET_TIMEOUT: - lo->xmit_timeout = arg * HZ; + nbd->xmit_timeout = arg * HZ; return 0; + + case NBD_SET_FLAGS: + nbd->flags = arg; + return 0; + case NBD_SET_SIZE_BLOCKS: - lo->bytesize = ((u64) arg) * lo->blksize; - bdev->bd_inode->i_size = lo->bytesize; - set_blocksize(bdev, lo->blksize); - set_capacity(lo->disk, lo->bytesize >> 9); + nbd->bytesize = ((u64) arg) * nbd->blksize; + bdev->bd_inode->i_size = nbd->bytesize; + set_blocksize(bdev, nbd->blksize); + set_capacity(nbd->disk, nbd->bytesize >> 9); return 0; - case NBD_DO_IT: - if (lo->pid) + + case NBD_DO_IT: { + struct task_struct *thread; + struct socket *sock; + int error; + + if (nbd->pid) return -EBUSY; - if (!lo->file) + if (!nbd->sock) return -EINVAL; - thread = kthread_create(nbd_thread, lo, lo->disk->disk_name); - if (IS_ERR(thread)) + + mutex_unlock(&nbd->tx_lock); + + 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_flush(nbd->disk->queue, REQ_FLUSH); + else + blk_queue_flush(nbd->disk->queue, 0); + + thread = kthread_create(nbd_thread, nbd, "%s", + nbd->disk->disk_name); + if (IS_ERR(thread)) { + mutex_lock(&nbd->tx_lock); return PTR_ERR(thread); + } wake_up_process(thread); - error = nbd_do_it(lo); + error = nbd_do_it(nbd); kthread_stop(thread); + + mutex_lock(&nbd->tx_lock); if (error) return error; - sock_shutdown(lo, 1); - file = lo->file; - lo->file = NULL; - nbd_clear_que(lo); - printk(KERN_WARNING "%s: queue cleared\n", lo->disk->disk_name); - if (file) - fput(file); - lo->bytesize = 0; + sock_shutdown(nbd, 0); + sock = nbd->sock; + nbd->sock = NULL; + nbd_clear_que(nbd); + dev_warn(disk_to_dev(nbd->disk), "queue cleared\n"); + kill_bdev(bdev); + queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); + set_device_ro(bdev, false); + if (sock) + sockfd_put(sock); + nbd->flags = 0; + nbd->bytesize = 0; bdev->bd_inode->i_size = 0; - set_capacity(lo->disk, 0); + set_capacity(nbd->disk, 0); if (max_part > 0) ioctl_by_bdev(bdev, BLKRRPART, 0); - return lo->harderror; + if (nbd->disconnect) /* user requested, ignore socket errors */ + return 0; + return nbd->harderror; + } + case NBD_CLEAR_QUE: /* * This is for compatibility only. The queue is always cleared * by NBD_DO_IT or NBD_CLEAR_SOCK. */ - BUG_ON(!lo->sock && !list_empty(&lo->queue_head)); return 0; + case NBD_PRINT_DEBUG: - printk(KERN_INFO "%s: next = %p, prev = %p, head = %p\n", - bdev->bd_disk->disk_name, - lo->queue_head.next, lo->queue_head.prev, - &lo->queue_head); + dev_info(disk_to_dev(nbd->disk), + "next = %p, prev = %p, head = %p\n", + nbd->queue_head.next, nbd->queue_head.prev, + &nbd->queue_head); return 0; } - return -EINVAL; + return -ENOTTY; } -static struct block_device_operations nbd_fops = +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); + + /* Anyone capable of this syscall can do *real bad* things */ + dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n", + nbd->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg); + + mutex_lock(&nbd->tx_lock); + error = __nbd_ioctl(bdev, nbd, cmd, arg); + mutex_unlock(&nbd->tx_lock); + + return error; +} + +static const struct block_device_operations nbd_fops = { .owner = THIS_MODULE, - .locked_ioctl = nbd_ioctl, + .ioctl = nbd_ioctl, }; /* @@ -721,7 +799,7 @@ static int __init nbd_init(void) BUILD_BUG_ON(sizeof(struct nbd_request) != 28); if (max_part < 0) { - printk(KERN_CRIT "nbd: max_part must be >= 0\n"); + printk(KERN_ERR "nbd: max_part must be >= 0\n"); return -EINVAL; } @@ -730,9 +808,26 @@ static int __init nbd_init(void) return -ENOMEM; part_shift = 0; - if (max_part > 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; + for (i = 0; i < nbds_max; i++) { struct gendisk *disk = alloc_disk(1 << part_shift); if (!disk) @@ -752,6 +847,11 @@ static int __init nbd_init(void) * Tell the block layer that we are not a rotational device */ queue_flag_set_unlocked(QUEUE_FLAG_NONROT, disk->queue); + disk->queue->limits.discard_granularity = 512; + disk->queue->limits.max_discard_sectors = 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")) { @@ -764,9 +864,7 @@ static int __init nbd_init(void) for (i = 0; i < nbds_max; i++) { struct gendisk *disk = nbd_dev[i].disk; - nbd_dev[i].file = NULL; - nbd_dev[i].magic = LO_MAGIC; - nbd_dev[i].flags = 0; + nbd_dev[i].magic = NBD_MAGIC; INIT_LIST_HEAD(&nbd_dev[i].waiting_queue); spin_lock_init(&nbd_dev[i].queue_lock); INIT_LIST_HEAD(&nbd_dev[i].queue_head); |
