sys/vfs/userfs/userfs_inode.c

   1 /*
   2  * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vfs/userfs/userfs_inode.c,v 1.1 2007/08/13 17:49:17 dillon Exp $
  35  */
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/kernel.h>
  40 #include <sys/vnode.h>
  41 #include <sys/mount.h>
  42 #include <sys/malloc.h>
  43 #include <sys/syslink.h>
  44 #include <sys/syslink_msg2.h>
  45 #include <sys/syslink_vfs.h>
  46 #include "userfs.h"
  47
  48 static MALLOC_DEFINE(M_USERFSINODE, "userfs-inode", "userfs inode");
  49
  50 int
  51 user_vop_inactive(struct vop_inactive_args *ap)
  52 {
  53         return(0);
  54 }
  55
  56 int
  57 user_vop_reclaim(struct vop_reclaim_args *ap)
  58 {
  59         struct user_mount *ump;
  60         struct user_inode *ip;
  61         struct vnode *vp;
  62
  63         vp = ap->a_vp;
  64         if ((ip = vp->v_data) != NULL) {
  65                 ump = ip->ump;
  66
  67                 userfs_ino_rb_tree_RB_REMOVE(&ump->rb_root, ip);
  68                 vp->v_data = NULL;
  69                 ip->vp = NULL;
  70                 kfree(ip, M_USERFSINODE);
  71         }
  72         return(0);
  73 }
  74
  75 int
  76 user_vfs_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
  77 {
  78         struct user_mount *ump = (void *)mp->mnt_data;
  79         struct user_inode *ip;
  80         struct vnode *vp;
  81         int error;
  82
  83 again:
  84         kprintf("LOOKUP ump %p ino %lld\n", ump, ino);
  85         ip = userfs_ino_rb_tree_RB_LOOKUP(&ump->rb_root, ino);
  86         if (ip) {
  87                 vp = ip->vp;
  88                 vref(vp);
  89                 vn_lock(vp, LK_EXCLUSIVE|LK_RETRY);
  90                 if (vp->v_flag & VRECLAIMED) {
  91                         vput(vp);
  92                         goto again;
  93                 }
  94                 *vpp = vp;
  95                 return(0);
  96         }
  97
  98         /*
  99          * Locate the inode on-disk
 100          */
 101
 102         /*
 103          * Create a vnode and in-memory inode.
 104          */
 105         error = user_getnewvnode(mp, vpp, ino, VDIR);
 106         if (error == EAGAIN)
 107                 goto again;
 108         return (error);
 109 }
 110
 111 /*
 112  * Create a vnode and in-memory inode.  EAGAIN is returned if we race the
 113  * creation of the in-memory inode.
 114  *
 115  * A locked, referenced vnode is returned in *vpp if no error occurs.
 116  */
 117 int
 118 user_getnewvnode(struct mount *mp, struct vnode **vpp, ino_t ino,
 119                  enum vtype vtype)
 120 {
 121         struct user_inode *ip;
 122         struct user_mount *ump;
 123         struct vnode *vp;
 124         int error;
 125
 126         error = getnewvnode(VT_USERFS, mp, vpp, 0, LK_CANRECURSE);
 127         if (error)
 128                 return (error);
 129         vp = *vpp;
 130         ip = kmalloc(sizeof(*ip), M_USERFSINODE, M_WAITOK|M_ZERO);
 131         vinitvmio(vp, 0);
 132
 133         ump = (void *)mp->mnt_data;
 134
 135         /*
 136          * Snap together the new vnode/inode and determine if we have
 137          * raced the tree.
 138          */
 139         if (userfs_ino_rb_tree_RB_LOOKUP(&ump->rb_root, ino)) {
 140                 kfree(ip, M_USERFSINODE);
 141                 vp->v_type = VBAD;
 142                 vput(*vpp);
 143                 return (EAGAIN);
 144         }
 145         ip->inum = ino;
 146         ip->vp = vp;
 147         ip->ump = ump;
 148         vp->v_data = ip;
 149         vp->v_type = vtype;
 150         userfs_ino_rb_tree_RB_INSERT(&ump->rb_root, ip);
 151         return(0);
 152 }
 153