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, struct vnode *dvp,
  77               ino_t ino, struct vnode **vpp)
  78 {
  79         struct user_mount *ump = (void *)mp->mnt_data;
  80         struct user_inode *ip;
  81         struct vnode *vp;
  82         int error;
  83
  84 again:
  85         kprintf("LOOKUP ump %p ino %lld\n", ump, ino);
  86         ip = userfs_ino_rb_tree_RB_LOOKUP(&ump->rb_root, ino);
  87         if (ip) {
  88                 vp = ip->vp;
  89                 vref(vp);
  90                 vn_lock(vp, LK_EXCLUSIVE|LK_RETRY);
  91                 if (vp->v_flag & VRECLAIMED) {
  92                         vput(vp);
  93                         goto again;
  94                 }
  95                 *vpp = vp;
  96                 return(0);
  97         }
  98
  99         /*
 100          * Locate the inode on-disk
 101          */
 102
 103         /*
 104          * Create a vnode and in-memory inode.
 105          */
 106         error = user_getnewvnode(mp, vpp, ino, VDIR);
 107         if (error == EAGAIN)
 108                 goto again;
 109         return (error);
 110 }
 111
 112 /*
 113  * Create a vnode and in-memory inode.  EAGAIN is returned if we race the
 114  * creation of the in-memory inode.
 115  *
 116  * A locked, referenced vnode is returned in *vpp if no error occurs.
 117  */
 118 int
 119 user_getnewvnode(struct mount *mp, struct vnode **vpp, ino_t ino,
 120                  enum vtype vtype)
 121 {
 122         struct user_inode *ip;
 123         struct user_mount *ump;
 124         struct vnode *vp;
 125         int error;
 126
 127         error = getnewvnode(VT_USERFS, mp, vpp, 0, LK_CANRECURSE);
 128         if (error)
 129                 return (error);
 130         vp = *vpp;
 131         ip = kmalloc(sizeof(*ip), M_USERFSINODE, M_WAITOK|M_ZERO);
 132         vinitvmio(vp, 0, PAGE_SIZE, 0);
 133
 134         ump = (void *)mp->mnt_data;
 135
 136         /*
 137          * Snap together the new vnode/inode and determine if we have
 138          * raced the tree.
 139          */
 140         if (userfs_ino_rb_tree_RB_LOOKUP(&ump->rb_root, ino)) {
 141                 kfree(ip, M_USERFSINODE);
 142                 vp->v_type = VBAD;
 143                 vput(*vpp);
 144                 return (EAGAIN);
 145         }
 146         ip->inum = ino;
 147         ip->vp = vp;
 148         ip->ump = ump;
 149         vp->v_data = ip;
 150         vp->v_type = vtype;
 151         userfs_ino_rb_tree_RB_INSERT(&ump->rb_root, ip);
 152         return(0);
 153 }
 154