diff options
| -rw-r--r-- | drivers/block/nbd.c | 15 | ||||
| -rw-r--r-- | include/linux/nbd.h | 6 |
2 files changed, 19 insertions, 2 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 68fe7514413d..043ddcca4abf 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -98,6 +98,7 @@ 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_TRIM: return "trim/discard"; } return "invalid"; } @@ -469,7 +470,11 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *req) nbd_cmd(req) = NBD_CMD_READ; if (rq_data_dir(req) == WRITE) { - nbd_cmd(req) = NBD_CMD_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"); @@ -676,6 +681,10 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, mutex_unlock(&nbd->tx_lock); + if (nbd->flags & NBD_FLAG_SEND_TRIM) + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, + nbd->disk->queue); + thread = kthread_create(nbd_thread, nbd, nbd->disk->disk_name); if (IS_ERR(thread)) { mutex_lock(&nbd->tx_lock); @@ -693,6 +702,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, nbd->file = NULL; nbd_clear_que(nbd); dev_warn(disk_to_dev(nbd->disk), "queue cleared\n"); + queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); if (file) fput(file); nbd->bytesize = 0; @@ -811,6 +821,9 @@ 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; } if (register_blkdev(NBD_MAJOR, "nbd")) { diff --git a/include/linux/nbd.h b/include/linux/nbd.h index 4b8ed5a1cfb0..5c86e2b33e2d 100644 --- a/include/linux/nbd.h +++ b/include/linux/nbd.h @@ -32,12 +32,16 @@ enum { NBD_CMD_READ = 0, NBD_CMD_WRITE = 1, - NBD_CMD_DISC = 2 + NBD_CMD_DISC = 2, + /* there is a gap here to match userspace */ + NBD_CMD_TRIM = 4 }; /* values for flags field */ #define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */ #define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */ +/* there is a gap here to match userspace */ +#define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */ #define nbd_cmd(req) ((req)->cmd[0]) |