1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005 Poul-Henning Kamp 5 * All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 30 // Modified to support the Haiku FAT driver. 31 32 #ifdef FS_SHELL 33 #include "fssh_api_wrapper.h" 34 #else 35 #include <sys/stat.h> 36 #include <sys/types.h> 37 #endif 38 39 #include "sys/param.h" 40 #include "sys/systm.h" 41 #include "sys/buf.h" 42 #include "sys/mount.h" 43 #include "sys/namei.h" 44 #include "sys/vnode.h" 45 46 #include "fs/msdosfs/denode.h" 47 #include "fs/msdosfs/direntry.h" 48 49 #include "dosfs.h" 50 51 52 #ifdef USER 53 #define dprintf printf 54 #endif 55 56 57 /*! Determine the inode number for a direntry location and return the corresponding node if it is 58 constructed. 59 @param hash A tentative location-based inode. 60 @param arg Pointer to a pre-allocated uint64. 61 @param td Ignored in the port. 62 @param fn Ignored in the port. In FreeBSD, this is a function pointer that would be passed to 63 the VFS and applied to the VFS's list of vnodes to find a match. 64 @param arg Pointer to a pre-allocated uint64 that will be set to the final inode number. 65 @post *arg is set to the inode number corresponding to hash (which may or may not equal hash). 66 *vpp points to the corresponding BSD-style vnode, if that vnode already exists in memory. If 67 the node doesn't exist in memory, *vpp is set to NULL. 68 The function signature is modified to make hash a uint64 instead of uint32. This is consistent 69 with the type passed by deget, and protects against overflow. 70 This function never calls get_vnode when the node in question is not already registered with 71 the VFS, so it is suitable for use within dosfs_read_vnode. 72 */ 73 int 74 vfs_hash_get(struct mount* mp, uint64 hash, int flags, thread_id td, struct vnode** vpp, 75 vfs_hash_cmp_t* fn, void* arg) 76 { 77 uint64* finalInode = arg; 78 status_t status = B_OK; 79 bool exists = false; 80 // Has a node with the same inode number already been constructed? 81 82 status = assign_inode(mp, (ino_t*)&hash); 83 if (status != B_OK) 84 return B_TO_POSIX_ERROR(status); 85 86 exists = node_exists(mp, hash); 87 if (exists == true) { 88 // get_vnode will just return a ref (without calling dosfs_read_vnode) 89 status = get_vnode(mp->mnt_fsvolume, hash, (void**)vpp); 90 if (status != B_OK) { 91 dprintf("FAT vfs_hash_get: get_vnode failure\n"); 92 return B_TO_POSIX_ERROR(status); 93 } 94 rw_lock_write_lock(&(*vpp)->v_vnlock->haikuRW); 95 // the driver expects the node to be returned locked 96 } else { 97 // The node needs to be initialized. Returning with a NULL vpp will 98 // signal deget() to go through with setting it up. 99 *vpp = NULL; 100 } 101 102 *finalInode = hash; 103 104 return 0; 105 } 106 107 108 /*! In FreeBSD, this adds vp to a VFS-level list of nodes. In Haiku, the same thing is 109 taken care of automatically by get_vnode. 110 */ 111 int 112 vfs_hash_insert(struct vnode* vp, uint64 hash, int flags, thread_id td, struct vnode** vpp, 113 vfs_hash_cmp_t* fn, void* arg) 114 { 115 ASSERT(node_exists(vp->v_mount, hash) == false); 116 117 // This tells the client that there is no existing vnode with the same 118 // inode number. This should always be the case under the conditions in which 119 // the FAT driver calls this function: if there was an existing node, 120 // deget would have returned early. 121 *vpp = NULL; 122 123 return 0; 124 } 125 126 127 /*! In FreeBSD, this provides the VFS with an updated node hash value based on the new directory 128 entry offset when a file is renamed. Not applicable in Haiku. 129 */ 130 void 131 vfs_hash_rehash(struct vnode* vp, uint64 hash) 132 { 133 return; 134 } 135