diff options
Diffstat (limited to 'fs/nfs/blocklayout/blocklayoutdev.c')
| -rw-r--r-- | fs/nfs/blocklayout/blocklayoutdev.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/fs/nfs/blocklayout/blocklayoutdev.c b/fs/nfs/blocklayout/blocklayoutdev.c new file mode 100644 index 000000000000..7e1377fcfdce --- /dev/null +++ b/fs/nfs/blocklayout/blocklayoutdev.c @@ -0,0 +1,191 @@ +/* + * linux/fs/nfs/blocklayout/blocklayoutdev.c + * + * Device operations for the pnfs nfs4 file layout driver. + * + * Copyright (c) 2006 The Regents of the University of Michigan. + * All rights reserved. + * + * Andy Adamson <andros@citi.umich.edu> + * Fred Isaman <iisaman@umich.edu> + * + * permission is granted to use, copy, create derivative works and + * redistribute this software and such derivative works for any purpose, + * so long as the name of the university of michigan is not used in + * any advertising or publicity pertaining to the use or distribution + * of this software without specific, written prior authorization. if + * the above copyright notice or any other identification of the + * university of michigan is included in any copy of any portion of + * this software, then the disclaimer below must also be included. + * + * this software is provided as is, without representation from the + * university of michigan as to its fitness for any purpose, and without + * warranty by the university of michigan of any kind, either express + * or implied, including without limitation the implied warranties of + * merchantability and fitness for a particular purpose. the regents + * of the university of michigan shall not be liable for any damages, + * including special, indirect, incidental, or consequential damages, + * with respect to any claim arising out or in connection with the use + * of the software, even if it has been or is hereafter advised of the + * possibility of such damages. + */ +#include <linux/module.h> +#include <linux/buffer_head.h> /* __bread */ + +#include <linux/genhd.h> +#include <linux/blkdev.h> +#include <linux/hash.h> + +#include "blocklayout.h" + +#define NFSDBG_FACILITY NFSDBG_PNFS_LD + +/* Open a block_device by device number. */ +struct block_device *nfs4_blkdev_get(dev_t dev) +{ + struct block_device *bd; + + dprintk("%s enter\n", __func__); + bd = blkdev_get_by_dev(dev, FMODE_READ, NULL); + if (IS_ERR(bd)) + goto fail; + return bd; +fail: + dprintk("%s failed to open device : %ld\n", + __func__, PTR_ERR(bd)); + return NULL; +} + +/* + * Release the block device + */ +int nfs4_blkdev_put(struct block_device *bdev) +{ + dprintk("%s for device %d:%d\n", __func__, MAJOR(bdev->bd_dev), + MINOR(bdev->bd_dev)); + return blkdev_put(bdev, FMODE_READ); +} + +/* + * Shouldn't there be a rpc_generic_upcall() to do this for us? + */ +ssize_t bl_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, + char __user *dst, size_t buflen) +{ + char *data = (char *)msg->data + msg->copied; + size_t mlen = min(msg->len - msg->copied, buflen); + unsigned long left; + + left = copy_to_user(dst, data, mlen); + if (left == mlen) { + msg->errno = -EFAULT; + return -EFAULT; + } + + mlen -= left; + msg->copied += mlen; + msg->errno = 0; + return mlen; +} + +static struct bl_dev_msg bl_mount_reply; + +ssize_t bl_pipe_downcall(struct file *filp, const char __user *src, + size_t mlen) +{ + if (mlen != sizeof (struct bl_dev_msg)) + return -EINVAL; + + if (copy_from_user(&bl_mount_reply, src, mlen) != 0) + return -EFAULT; + + wake_up(&bl_wq); + + return mlen; +} + +void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg) +{ + if (msg->errno >= 0) + return; + wake_up(&bl_wq); +} + +/* + * Decodes pnfs_block_deviceaddr4 which is XDR encoded in dev->dev_addr_buf. + */ +struct pnfs_block_dev * +nfs4_blk_decode_device(struct nfs_server *server, + struct pnfs_device *dev, + struct list_head *sdlist) +{ + struct pnfs_block_dev *rv = NULL; + struct block_device *bd = NULL; + struct rpc_pipe_msg msg; + struct bl_msg_hdr bl_msg = { + .type = BL_DEVICE_MOUNT, + .totallen = dev->mincount, + }; + uint8_t *dataptr; + DECLARE_WAITQUEUE(wq, current); + struct bl_dev_msg *reply = &bl_mount_reply; + + dprintk("%s CREATING PIPEFS MESSAGE\n", __func__); + dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data, + dev->mincount); + + memset(&msg, 0, sizeof(msg)); + msg.data = kzalloc(sizeof(bl_msg) + dev->mincount, GFP_NOFS); + if (!msg.data) { + rv = ERR_PTR(-ENOMEM); + goto out; + } + + memcpy(msg.data, &bl_msg, sizeof(bl_msg)); + dataptr = (uint8_t *) msg.data; + memcpy(&dataptr[sizeof(bl_msg)], dev->area, dev->mincount); + msg.len = sizeof(bl_msg) + dev->mincount; + + dprintk("%s CALLING USERSPACE DAEMON\n", __func__); + add_wait_queue(&bl_wq, &wq); + if (rpc_queue_upcall(bl_device_pipe->d_inode, &msg) < 0) { + remove_wait_queue(&bl_wq, &wq); + goto out; + } + + set_current_state(TASK_UNINTERRUPTIBLE); + schedule(); + __set_current_state(TASK_RUNNING); + remove_wait_queue(&bl_wq, &wq); + + if (reply->status != BL_DEVICE_REQUEST_PROC) { + dprintk("%s failed to open device: %d\n", + __func__, reply->status); + rv = ERR_PTR(-EINVAL); + goto out; + } + + bd = nfs4_blkdev_get(MKDEV(reply->major, reply->minor)); + if (IS_ERR(bd)) { + dprintk("%s failed to open device : %ld\n", + __func__, PTR_ERR(bd)); + goto out; + } + + rv = kzalloc(sizeof(*rv), GFP_NOFS); + if (!rv) { + rv = ERR_PTR(-ENOMEM); + goto out; + } + + rv->bm_mdev = bd; + memcpy(&rv->bm_mdevid, &dev->dev_id, sizeof(struct nfs4_deviceid)); + dprintk("%s Created device %s with bd_block_size %u\n", + __func__, + bd->bd_disk->disk_name, + bd->bd_block_size); + +out: + kfree(msg.data); + return rv; +} |