fs/nfs/blocklayout/blocklayoutdm.c

   1 /*
   2  *  linux/fs/nfs/blocklayout/blocklayoutdm.c
   3  *
   4  *  Module for the NFSv4.1 pNFS block layout driver.
   5  *
   6  *  Copyright (c) 2007 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Fred Isaman <iisaman@umich.edu>
  10  *  Andy Adamson <andros@citi.umich.edu>
  11  *
  12  * permission is granted to use, copy, create derivative works and
  13  * redistribute this software and such derivative works for any purpose,
  14  * so long as the name of the university of michigan is not used in
  15  * any advertising or publicity pertaining to the use or distribution
  16  * of this software without specific, written prior authorization.  if
  17  * the above copyright notice or any other identification of the
  18  * university of michigan is included in any copy of any portion of
  19  * this software, then the disclaimer below must also be included.
  20  *
  21  * this software is provided as is, without representation from the
  22  * university of michigan as to its fitness for any purpose, and without
  23  * warranty by the university of michigan of any kind, either express
  24  * or implied, including without limitation the implied warranties of
  25  * merchantability and fitness for a particular purpose.  the regents
  26  * of the university of michigan shall not be liable for any damages,
  27  * including special, indirect, incidental, or consequential damages,
  28  * with respect to any claim arising out or in connection with the use
  29  * of the software, even if it has been or is hereafter advised of the
  30  * possibility of such damages.
  31  */
  32
  33 #include <linux/genhd.h> /* gendisk - used in a dprintk*/
  34 #include <linux/sched.h>
  35 #include <linux/hash.h>
  36
  37 #include "blocklayout.h"
  38
  39 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  40
  41 static void dev_remove(struct net *net, dev_t dev)
  42 {
  43         struct bl_pipe_msg bl_pipe_msg;
  44         struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
  45         struct bl_dev_msg bl_umount_request;
  46         struct bl_msg_hdr bl_msg = {
  47                 .type = BL_DEVICE_UMOUNT,
  48                 .totallen = sizeof(bl_umount_request),
  49         };
  50         uint8_t *dataptr;
  51         DECLARE_WAITQUEUE(wq, current);
  52         struct nfs_net *nn = net_generic(net, nfs_net_id);
  53
  54         dprintk("Entering %s\n", __func__);
  55
  56         bl_pipe_msg.bl_wq = &nn->bl_wq;
  57         memset(msg, 0, sizeof(*msg));
  58         msg->data = kzalloc(1 + sizeof(bl_umount_request), GFP_NOFS);
  59         if (!msg->data)
  60                 goto out;
  61
  62         memset(&bl_umount_request, 0, sizeof(bl_umount_request));
  63         bl_umount_request.major = MAJOR(dev);
  64         bl_umount_request.minor = MINOR(dev);
  65
  66         memcpy(msg->data, &bl_msg, sizeof(bl_msg));
  67         dataptr = (uint8_t *) msg->data;
  68         memcpy(&dataptr[sizeof(bl_msg)], &bl_umount_request, sizeof(bl_umount_request));
  69         msg->len = sizeof(bl_msg) + bl_msg.totallen;
  70
  71         add_wait_queue(&nn->bl_wq, &wq);
  72         if (rpc_queue_upcall(nn->bl_device_pipe, msg) < 0) {
  73                 remove_wait_queue(&nn->bl_wq, &wq);
  74                 goto out;
  75         }
  76
  77         set_current_state(TASK_UNINTERRUPTIBLE);
  78         schedule();
  79         __set_current_state(TASK_RUNNING);
  80         remove_wait_queue(&nn->bl_wq, &wq);
  81
  82 out:
  83         kfree(msg->data);
  84 }
  85
  86 /*
  87  * Release meta device
  88  */
  89 static void nfs4_blk_metadev_release(struct pnfs_block_dev *bdev)
  90 {
  91         int rv;
  92
  93         dprintk("%s Releasing\n", __func__);
  94         rv = nfs4_blkdev_put(bdev->bm_mdev);
  95         if (rv)
  96                 printk(KERN_ERR "NFS: %s nfs4_blkdev_put returns %d\n",
  97                                 __func__, rv);
  98
  99         dev_remove(bdev->net, bdev->bm_mdev->bd_dev);
 100 }
 101
 102 void bl_free_block_dev(struct pnfs_block_dev *bdev)
 103 {
 104         if (bdev) {
 105                 if (bdev->bm_mdev) {
 106                         dprintk("%s Removing DM device: %d:%d\n",
 107                                 __func__,
 108                                 MAJOR(bdev->bm_mdev->bd_dev),
 109                                 MINOR(bdev->bm_mdev->bd_dev));
 110                         nfs4_blk_metadev_release(bdev);
 111                 }
 112                 kfree(bdev);
 113         }
 114 }