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path: root/drivers/block/nbd.c
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Diffstat (limited to 'drivers/block/nbd.c')
-rw-r--r--drivers/block/nbd.c782
1 files changed, 494 insertions, 288 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 090796bef78..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.
@@ -24,18 +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...)
@@ -53,7 +56,8 @@ static unsigned int debugflags;
#endif /* NDEBUG */
static unsigned int nbds_max = 16;
-static struct nbd_device nbd_dev[MAX_NBD];
+static struct nbd_device *nbd_dev;
+static int max_part;
/*
* Use just one lock (or at most 1 per NIC). Two arguments for this:
@@ -74,6 +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";
@@ -92,6 +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";
}
@@ -99,43 +107,74 @@ static const char *nbdcmd_to_ascii(int cmd)
static void nbd_end_request(struct request *req)
{
- int uptodate = (req->errors == 0) ? 1 : 0;
- request_queue_t *q = req->q;
+ int error = req->errors ? -EIO : 0;
+ struct request_queue *q = req->q;
unsigned long flags;
dprintk(DBG_BLKDEV, "%s: request %p: %s\n", req->rq_disk->disk_name,
- req, uptodate? "done": "failed");
+ req, error ? "failed" : "done");
spin_lock_irqsave(q->queue_lock, flags);
- if (!end_that_request_first(req, uptodate, req->nr_sectors)) {
- end_that_request_last(req, uptodate);
- }
+ __blk_end_request_all(req, error);
spin_unlock_irqrestore(q->queue_lock, flags);
}
+static void sock_shutdown(struct nbd_device *nbd, int lock)
+{
+ /* Forcibly shutdown the socket causing all listeners
+ * to error
+ *
+ * FIXME: This code is duplicated from sys_shutdown, but
+ * there should be a more generic interface rather than
+ * calling socket ops directly here */
+ if (lock)
+ 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(&nbd->tx_lock);
+}
+
+static void nbd_xmit_timeout(unsigned long arg)
+{
+ struct task_struct *task = (struct task_struct *)arg;
+
+ printk(KERN_WARNING "nbd: killing hung xmit (%s, pid: %d)\n",
+ task->comm, task->pid);
+ force_sig(SIGKILL, task);
+}
+
/*
* Send or receive packet.
*/
-static int sock_xmit(struct socket *sock, 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 = nbd->sock;
int result;
struct msghdr msg;
struct kvec iov;
- unsigned long flags;
- sigset_t oldset;
+ sigset_t blocked, oldset;
+ unsigned long pflags = current->flags;
+
+ if (unlikely(!sock)) {
+ dev_err(disk_to_dev(nbd->disk),
+ "Attempted %s on closed socket in sock_xmit\n",
+ (send ? "send" : "recv"));
+ return -EINVAL;
+ }
/* Allow interception of SIGKILL only
* Don't allow other signals to interrupt the transmission */
- spin_lock_irqsave(&current->sighand->siglock, flags);
- oldset = current->blocked;
- sigfillset(&current->blocked);
- sigdelsetmask(&current->blocked, sigmask(SIGKILL));
- recalc_sigpending();
- spin_unlock_irqrestore(&current->sighand->siglock, flags);
+ 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;
@@ -144,19 +183,30 @@ static int sock_xmit(struct socket *sock, int send, void *buf, int size,
msg.msg_controllen = 0;
msg.msg_flags = msg_flags | MSG_NOSIGNAL;
- if (send)
+ if (send) {
+ struct timer_list ti;
+
+ if (nbd->xmit_timeout) {
+ init_timer(&ti);
+ ti.function = nbd_xmit_timeout;
+ ti.data = (unsigned long)current;
+ ti.expires = jiffies + nbd->xmit_timeout;
+ add_timer(&ti);
+ }
result = kernel_sendmsg(sock, &msg, &iov, 1, size);
- else
- result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);
+ if (nbd->xmit_timeout)
+ del_timer_sync(&ti);
+ } else
+ result = kernel_recvmsg(sock, &msg, &iov, 1, size,
+ msg.msg_flags);
if (signal_pending(current)) {
siginfo_t info;
- spin_lock_irqsave(&current->sighand->siglock, flags);
printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n",
- current->pid, current->comm,
- dequeue_signal(current, &current->blocked, &info));
- spin_unlock_irqrestore(&current->sighand->siglock, flags);
+ task_pid_nr(current), current->comm,
+ dequeue_signal_lock(current, &current->blocked, &info));
result = -EINTR;
+ sock_shutdown(nbd, !send);
break;
}
@@ -169,105 +219,100 @@ static int sock_xmit(struct socket *sock, int send, void *buf, int size,
buf += result;
} while (size > 0);
- spin_lock_irqsave(&current->sighand->siglock, flags);
- current->blocked = oldset;
- recalc_sigpending();
- spin_unlock_irqrestore(&current->sighand->siglock, flags);
+ sigprocmask(SIG_SETMASK, &oldset, NULL);
+ tsk_restore_flags(current, pflags, PF_MEMALLOC);
return result;
}
-static inline int sock_send_bvec(struct socket *sock, 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(sock, 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;
}
-static int nbd_send_req(struct nbd_device *lo, struct request *req)
+/* always call with the tx_lock held */
+static int nbd_send_req(struct nbd_device *nbd, struct request *req)
{
- int result, i, flags;
+ int result, flags;
struct nbd_request request;
- unsigned long size = req->nr_sectors << 9;
- struct socket *sock = lo->sock;
+ 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(sock, 1, &request, sizeof(request),
- (nbd_cmd(req) == NBD_CMD_WRITE)? MSG_MORE: 0);
+ (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 bio *bio;
+ struct req_iterator iter;
+ struct bio_vec bvec;
/*
* we are really probing at internals to determine
* whether to set MSG_MORE or not...
*/
- rq_for_each_bio(bio, req) {
- struct bio_vec *bvec;
- bio_for_each_segment(bvec, bio, i) {
- flags = 0;
- if ((i < (bio->bi_vcnt - 1)) || bio->bi_next)
- 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(sock, bvec, flags);
- if (result <= 0) {
- printk(KERN_ERR "%s: Send data failed (result %d)\n",
- lo->disk->disk_name,
- result);
- goto error_out;
- }
+ rq_for_each_segment(bvec, req, iter) {
+ flags = 0;
+ if (!rq_iter_last(bvec, iter))
+ flags = MSG_MORE;
+ dprintk(DBG_TX, "%s: request %p: sending %d bytes data\n",
+ nbd->disk->disk_name, req, bvec.bv_len);
+ result = sock_send_bvec(nbd, &bvec, flags);
+ if (result <= 0) {
+ dev_err(disk_to_dev(nbd->disk),
+ "Send data failed (result %d)\n",
+ result);
+ goto error_out;
}
}
}
return 0;
error_out:
- return 1;
+ return -EIO;
}
-static struct request *nbd_find_request(struct nbd_device *lo, char *handle)
+static struct request *nbd_find_request(struct nbd_device *nbd,
+ struct request *xreq)
{
- struct request *req;
- struct list_head *tmp;
- struct request *xreq;
+ struct request *req, *tmp;
int err;
- memcpy(&xreq, handle, sizeof(xreq));
-
- 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(tmp, &lo->queue_head) {
- req = list_entry(tmp, struct request, 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;
@@ -275,132 +320,146 @@ out:
return ERR_PTR(err);
}
-static inline int sock_recv_bvec(struct socket *sock, 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(sock, 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;
- struct socket *sock = lo->sock;
reply.magic = 0;
- result = sock_xmit(sock, 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, reply.handle);
- if (unlikely(IS_ERR(req))) {
+ 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) {
- int i;
- struct bio *bio;
- rq_for_each_bio(bio, req) {
- struct bio_vec *bvec;
- bio_for_each_segment(bvec, bio, i) {
- result = sock_recv_bvec(sock, bvec);
- if (result <= 0) {
- printk(KERN_ERR "%s: Receive data failed (result %d)\n",
- lo->disk->disk_name,
- result);
- req->errors++;
- return req;
- }
- dprintk(DBG_RX, "%s: request %p: got %d bytes data\n",
- lo->disk->disk_name, req, bvec->bv_len);
+ struct req_iterator iter;
+ struct bio_vec bvec;
+
+ rq_for_each_segment(bvec, req, iter) {
+ result = sock_recv_bvec(nbd, &bvec);
+ if (result <= 0) {
+ 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",
+ nbd->disk->disk_name, req, bvec.bv_len);
}
}
return req;
harderror:
- lo->harderror = result;
+ nbd->harderror = result;
return NULL;
}
-static ssize_t pid_show(struct gendisk *disk, char *page)
+static ssize_t pid_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
- return sprintf(page, "%ld\n",
+ struct gendisk *disk = dev_to_disk(dev);
+
+ return sprintf(buf, "%ld\n",
(long) ((struct nbd_device *)disk->private_data)->pid);
}
-static struct disk_attribute pid_attr = {
- .attr = { .name = "pid", .mode = S_IRUGO },
+static struct device_attribute pid_attr = {
+ .attr = { .name = "pid", .mode = S_IRUGO},
.show = pid_show,
};
-static void 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;
- sysfs_create_file(&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) {
+ 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(&lo->disk->kobj, &pid_attr.attr);
- return;
+ 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++;
@@ -408,209 +467,319 @@ static void nbd_clear_que(struct nbd_device *lo)
}
}
+
+static void nbd_handle_req(struct nbd_device *nbd, struct request *req)
+{
+ if (req->cmd_type != REQ_TYPE_FS)
+ goto error_out;
+
+ nbd_cmd(req) = NBD_CMD_READ;
+ if (rq_data_dir(req) == WRITE) {
+ 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(&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;
+ }
+
+ nbd->active_req = req;
+
+ 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(&nbd->queue_lock);
+ list_add_tail(&req->queuelist, &nbd->queue_head);
+ spin_unlock(&nbd->queue_lock);
+ }
+
+ nbd->active_req = NULL;
+ mutex_unlock(&nbd->tx_lock);
+ wake_up_all(&nbd->active_wq);
+
+ return;
+
+error_out:
+ req->errors++;
+ nbd_end_request(req);
+}
+
+static int nbd_thread(void *data)
+{
+ struct nbd_device *nbd = data;
+ struct request *req;
+
+ set_user_nice(current, MIN_NICE);
+ while (!kthread_should_stop() || !list_empty(&nbd->waiting_queue)) {
+ /* wait for something to do */
+ wait_event_interruptible(nbd->waiting_wq,
+ kthread_should_stop() ||
+ !list_empty(&nbd->waiting_queue));
+
+ /* extract request */
+ if (list_empty(&nbd->waiting_queue))
+ continue;
+
+ spin_lock_irq(&nbd->queue_lock);
+ req = list_entry(nbd->waiting_queue.next, struct request,
+ queuelist);
+ list_del_init(&req->queuelist);
+ spin_unlock_irq(&nbd->queue_lock);
+
+ /* handle request */
+ nbd_handle_req(nbd, req);
+ }
+ return 0;
+}
+
/*
* We always wait for result of write, for now. It would be nice to make it optional
* in future
- * if ((req->cmd == 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(request_queue_t * 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;
+ while ((req = blk_fetch_request(q)) != NULL) {
+ struct nbd_device *nbd;
+
+ spin_unlock_irq(q->queue_lock);
- blkdev_dequeue_request(req);
dprintk(DBG_BLKDEV, "%s: request %p: dequeued (flags=%x)\n",
req->rq_disk->disk_name, req, req->cmd_type);
- if (!blk_fs_request(req))
- goto error_out;
-
- lo = req->rq_disk->private_data;
-
- BUG_ON(lo->magic != LO_MAGIC);
+ nbd = req->rq_disk->private_data;
- 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);
- goto error_out;
- }
- }
+ BUG_ON(nbd->magic != NBD_MAGIC);
- req->errors = 0;
- spin_unlock_irq(q->queue_lock);
-
- 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);
+ 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;
}
- lo->active_req = req;
-
- if (nbd_send_req(lo, req) != 0) {
- printk(KERN_ERR "%s: Request send failed\n",
- lo->disk->disk_name);
- 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_irq(&nbd->queue_lock);
+ list_add_tail(&req->queuelist, &nbd->waiting_queue);
+ spin_unlock_irq(&nbd->queue_lock);
- lo->active_req = NULL;
- mutex_unlock(&lo->tx_lock);
- wake_up_all(&lo->active_wq);
+ wake_up(&nbd->waiting_wq);
spin_lock_irq(q->queue_lock);
- continue;
-
-error_out:
- req->errors++;
- spin_unlock(q->queue_lock);
- nbd_end_request(req);
- spin_lock(q->queue_lock);
}
- return;
}
-static int nbd_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- struct nbd_device *lo = inode->i_bdev->bd_disk->private_data;
- int error;
- struct request sreq ;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
+/* Must be called with tx_lock held */
- 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;
- nbd_send_req(lo, &sreq);
- 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) {
- inode = file->f_path.dentry->d_inode;
- if (S_ISSOCK(inode->i_mode)) {
- lo->file = file;
- lo->sock = SOCKET_I(inode);
- 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);
- inode->i_bdev->bd_inode->i_size = lo->bytesize;
- set_blocksize(inode->i_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);
- inode->i_bdev->bd_inode->i_size = lo->bytesize;
- set_blocksize(inode->i_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:
+ 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;
- inode->i_bdev->bd_inode->i_size = lo->bytesize;
- set_blocksize(inode->i_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->file)
+
+ case NBD_DO_IT: {
+ struct task_struct *thread;
+ struct socket *sock;
+ int error;
+
+ if (nbd->pid)
+ return -EBUSY;
+ if (!nbd->sock)
return -EINVAL;
- nbd_do_it(lo);
- /* on return tidy up in case we have a signal */
- /* Forcibly shutdown the socket causing all listeners
- * to error
- *
- * FIXME: This code is duplicated from sys_shutdown, but
- * there should be a more generic interface rather than
- * calling socket ops directly here */
- mutex_lock(&lo->tx_lock);
- if (lo->sock) {
- printk(KERN_WARNING "%s: shutting down socket\n",
- lo->disk->disk_name);
- lo->sock->ops->shutdown(lo->sock,
- SEND_SHUTDOWN|RCV_SHUTDOWN);
- lo->sock = NULL;
+
+ 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);
}
- mutex_unlock(&lo->tx_lock);
- 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);
- return lo->harderror;
+ wake_up_process(thread);
+ error = nbd_do_it(nbd);
+ kthread_stop(thread);
+
+ mutex_lock(&nbd->tx_lock);
+ if (error)
+ return error;
+ 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(nbd->disk, 0);
+ if (max_part > 0)
+ ioctl_by_bdev(bdev, BLKRRPART, 0);
+ 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",
- inode->i_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 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 struct block_device_operations nbd_fops =
+static const struct block_device_operations nbd_fops =
{
.owner = THIS_MODULE,
.ioctl = nbd_ioctl,
@@ -625,17 +794,42 @@ static int __init nbd_init(void)
{
int err = -ENOMEM;
int i;
+ int part_shift;
BUILD_BUG_ON(sizeof(struct nbd_request) != 28);
- if (nbds_max > MAX_NBD) {
- printk(KERN_CRIT "nbd: cannot allocate more than %u nbds; %u requested.\n", MAX_NBD,
- nbds_max);
+ if (max_part < 0) {
+ printk(KERN_ERR "nbd: max_part must be >= 0\n");
return -EINVAL;
}
+ nbd_dev = kcalloc(nbds_max, sizeof(*nbd_dev), GFP_KERNEL);
+ if (!nbd_dev)
+ return -ENOMEM;
+
+ 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;
+
for (i = 0; i < nbds_max; i++) {
- struct gendisk *disk = alloc_disk(1);
+ struct gendisk *disk = alloc_disk(1 << part_shift);
if (!disk)
goto out;
nbd_dev[i].disk = disk;
@@ -649,6 +843,15 @@ static int __init nbd_init(void)
put_disk(disk);
goto out;
}
+ /*
+ * 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")) {
@@ -661,22 +864,21 @@ 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);
mutex_init(&nbd_dev[i].tx_lock);
init_waitqueue_head(&nbd_dev[i].active_wq);
+ init_waitqueue_head(&nbd_dev[i].waiting_wq);
nbd_dev[i].blksize = 1024;
- nbd_dev[i].bytesize = 0x7ffffc00ULL << 10; /* 2TB */
+ nbd_dev[i].bytesize = 0;
disk->major = NBD_MAJOR;
- disk->first_minor = i;
+ disk->first_minor = i << part_shift;
disk->fops = &nbd_fops;
disk->private_data = &nbd_dev[i];
- disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
sprintf(disk->disk_name, "nbd%d", i);
- set_capacity(disk, 0x7ffffc00ULL << 1); /* 2 TB */
+ set_capacity(disk, 0);
add_disk(disk);
}
@@ -686,6 +888,7 @@ out:
blk_cleanup_queue(nbd_dev[i].disk->queue);
put_disk(nbd_dev[i].disk);
}
+ kfree(nbd_dev);
return err;
}
@@ -702,6 +905,7 @@ static void __exit nbd_cleanup(void)
}
}
unregister_blkdev(NBD_MAJOR, "nbd");
+ kfree(nbd_dev);
printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR);
}
@@ -712,7 +916,9 @@ MODULE_DESCRIPTION("Network Block Device");
MODULE_LICENSE("GPL");
module_param(nbds_max, int, 0444);
-MODULE_PARM_DESC(nbds_max, "How many network block devices to initialize.");
+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)");
#ifndef NDEBUG
module_param(debugflags, int, 0644);
MODULE_PARM_DESC(debugflags, "flags for controlling debug output");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-24 11:03:28 +0000