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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.c148
1 files changed, 59 insertions, 89 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 4bc2a5cb9935..39e5f7fae3ef 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -32,28 +32,36 @@
#include <net/sock.h>
#include <linux/net.h>
#include <linux/kthread.h>
+#include <linux/types.h>
#include <asm/uaccess.h>
#include <asm/types.h>
#include <linux/nbd.h>
-#define NBD_MAGIC 0x68797548
+struct nbd_device {
+ int flags;
+ int harderror; /* Code of hard error */
+ struct socket * sock; /* If == NULL, device is not ready, yet */
+ int magic;
+
+ spinlock_t queue_lock;
+ struct list_head queue_head; /* Requests waiting result */
+ struct request *active_req;
+ wait_queue_head_t active_wq;
+ struct list_head waiting_queue; /* Requests to be sent */
+ wait_queue_head_t waiting_wq;
+
+ struct mutex tx_lock;
+ struct gendisk *disk;
+ int blksize;
+ loff_t bytesize;
+ pid_t pid; /* pid of nbd-client, if attached */
+ int xmit_timeout;
+ int disconnect; /* a disconnect has been requested by user */
+};
-#ifdef NDEBUG
-#define dprintk(flags, fmt...)
-#else /* NDEBUG */
-#define dprintk(flags, fmt...) do { \
- if (debugflags & (flags)) printk(KERN_DEBUG fmt); \
-} while (0)
-#define DBG_IOCTL 0x0004
-#define DBG_INIT 0x0010
-#define DBG_EXIT 0x0020
-#define DBG_BLKDEV 0x0100
-#define DBG_RX 0x0200
-#define DBG_TX 0x0400
-static unsigned int debugflags;
-#endif /* NDEBUG */
+#define NBD_MAGIC 0x68797548
static unsigned int nbds_max = 16;
static struct nbd_device *nbd_dev;
@@ -71,25 +79,9 @@ static int max_part;
*/
static DEFINE_SPINLOCK(nbd_lock);
-#ifndef NDEBUG
-static const char *ioctl_cmd_to_ascii(int cmd)
+static inline struct device *nbd_to_dev(struct nbd_device *nbd)
{
- switch (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";
- case NBD_PRINT_DEBUG: return "print-debug";
- case NBD_SET_SIZE_BLOCKS: return "set-size-blocks";
- case NBD_DISCONNECT: return "disconnect";
- case BLKROSET: return "set-read-only";
- case BLKFLSBUF: return "flush-buffer-cache";
- }
- return "unknown";
+ return disk_to_dev(nbd->disk);
}
static const char *nbdcmd_to_ascii(int cmd)
@@ -103,30 +95,26 @@ static const char *nbdcmd_to_ascii(int cmd)
}
return "invalid";
}
-#endif /* NDEBUG */
-static void nbd_end_request(struct request *req)
+static void nbd_end_request(struct nbd_device *nbd, struct request *req)
{
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, error ? "failed" : "done");
+ dev_dbg(nbd_to_dev(nbd), "request %p: %s\n", req,
+ error ? "failed" : "done");
spin_lock_irqsave(q->queue_lock, flags);
__blk_end_request_all(req, error);
spin_unlock_irqrestore(q->queue_lock, flags);
}
+/*
+ * Forcibly shutdown the socket causing all listeners to error
+ */
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) {
@@ -253,17 +241,15 @@ static int nbd_send_req(struct nbd_device *nbd, struct request *req)
}
memcpy(request.handle, &req, sizeof(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)blk_rq_pos(req) << 9,
- blk_rq_bytes(req));
+ dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n",
+ req, nbdcmd_to_ascii(nbd_cmd(req)),
+ (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) {
dev_err(disk_to_dev(nbd->disk),
"Send control failed (result %d)\n", result);
- goto error_out;
+ return -EIO;
}
if (nbd_cmd(req) == NBD_CMD_WRITE) {
@@ -277,21 +263,18 @@ static int nbd_send_req(struct nbd_device *nbd, struct request *req)
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);
+ dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n",
+ 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 -EIO;
}
}
}
return 0;
-
-error_out:
- return -EIO;
}
static struct request *nbd_find_request(struct nbd_device *nbd,
@@ -302,7 +285,7 @@ static struct request *nbd_find_request(struct nbd_device *nbd,
err = wait_event_interruptible(nbd->active_wq, nbd->active_req != xreq);
if (unlikely(err))
- goto out;
+ return ERR_PTR(err);
spin_lock(&nbd->queue_lock);
list_for_each_entry_safe(req, tmp, &nbd->queue_head, queuelist) {
@@ -314,10 +297,7 @@ static struct request *nbd_find_request(struct nbd_device *nbd,
}
spin_unlock(&nbd->queue_lock);
- err = -ENOENT;
-
-out:
- return ERR_PTR(err);
+ return ERR_PTR(-ENOENT);
}
static inline int sock_recv_bvec(struct nbd_device *nbd, struct bio_vec *bvec)
@@ -371,8 +351,7 @@ static struct request *nbd_read_stat(struct nbd_device *nbd)
return req;
}
- dprintk(DBG_RX, "%s: request %p: got reply\n",
- nbd->disk->disk_name, req);
+ dev_dbg(nbd_to_dev(nbd), "request %p: got reply\n", req);
if (nbd_cmd(req) == NBD_CMD_READ) {
struct req_iterator iter;
struct bio_vec bvec;
@@ -385,8 +364,8 @@ static struct request *nbd_read_stat(struct nbd_device *nbd)
req->errors++;
return req;
}
- dprintk(DBG_RX, "%s: request %p: got %d bytes data\n",
- nbd->disk->disk_name, req, bvec.bv_len);
+ dev_dbg(nbd_to_dev(nbd), "request %p: got %d bytes data\n",
+ req, bvec.bv_len);
}
}
return req;
@@ -426,7 +405,7 @@ static int nbd_do_it(struct nbd_device *nbd)
}
while ((req = nbd_read_stat(nbd)) != NULL)
- nbd_end_request(req);
+ nbd_end_request(nbd, req);
device_remove_file(disk_to_dev(nbd->disk), &pid_attr);
nbd->pid = 0;
@@ -455,7 +434,7 @@ static void nbd_clear_que(struct nbd_device *nbd)
queuelist);
list_del_init(&req->queuelist);
req->errors++;
- nbd_end_request(req);
+ nbd_end_request(nbd, req);
}
while (!list_empty(&nbd->waiting_queue)) {
@@ -463,7 +442,7 @@ static void nbd_clear_que(struct nbd_device *nbd)
queuelist);
list_del_init(&req->queuelist);
req->errors++;
- nbd_end_request(req);
+ nbd_end_request(nbd, req);
}
}
@@ -507,7 +486,7 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *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);
+ nbd_end_request(nbd, req);
} else {
spin_lock(&nbd->queue_lock);
list_add_tail(&req->queuelist, &nbd->queue_head);
@@ -522,7 +501,7 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *req)
error_out:
req->errors++;
- nbd_end_request(req);
+ nbd_end_request(nbd, req);
}
static int nbd_thread(void *data)
@@ -570,18 +549,18 @@ static void do_nbd_request(struct request_queue *q)
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);
-
nbd = req->rq_disk->private_data;
BUG_ON(nbd->magic != NBD_MAGIC);
+ dev_dbg(nbd_to_dev(nbd), "request %p: dequeued (flags=%x)\n",
+ req, req->cmd_type);
+
if (unlikely(!nbd->sock)) {
dev_err(disk_to_dev(nbd->disk),
"Attempted send on closed socket\n");
req->errors++;
- nbd_end_request(req);
+ nbd_end_request(nbd, req);
spin_lock_irq(q->queue_lock);
continue;
}
@@ -706,13 +685,13 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
else
blk_queue_flush(nbd->disk->queue, 0);
- thread = kthread_create(nbd_thread, nbd, "%s",
- nbd->disk->disk_name);
+ thread = kthread_run(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(nbd);
kthread_stop(thread);
@@ -768,10 +747,6 @@ static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
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);
@@ -803,10 +778,6 @@ static int __init nbd_init(void)
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);
@@ -828,6 +799,10 @@ static int __init nbd_init(void)
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 gendisk *disk = alloc_disk(1 << part_shift);
if (!disk)
@@ -861,7 +836,6 @@ static int __init nbd_init(void)
}
printk(KERN_INFO "nbd: registered device at major %d\n", NBD_MAJOR);
- dprintk(DBG_INIT, "nbd: debugflags=0x%x\n", debugflags);
for (i = 0; i < nbds_max; i++) {
struct gendisk *disk = nbd_dev[i].disk;
@@ -920,7 +894,3 @@ 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)");
-#ifndef NDEBUG
-module_param(debugflags, int, 0644);
-MODULE_PARM_DESC(debugflags, "flags for controlling debug output");
-#endif