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/* |
* Copyright (c) 2007 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
/** @addtogroup fs |
* @{ |
*/ |
|
/** |
* @file vfs.c |
* @brief VFS_REGISTER method. |
*/ |
|
#include <ipc/ipc.h> |
#include <ipc/services.h> |
#include <async.h> |
#include <errno.h> |
#include <stdio.h> |
#include <stdlib.h> |
#include <string.h> |
#include <ctype.h> |
#include <bool.h> |
#include <futex.h> |
#include <libadt/list.h> |
#include "vfs.h" |
|
atomic_t fs_head_futex = FUTEX_INITIALIZER; |
link_t fs_head; |
|
/** Verify the VFS info structure. |
* |
* @param info Info structure to be verified. |
* |
* @return Non-zero if the info structure is sane, zero otherwise. |
*/ |
static bool vfs_info_sane(vfs_info_t *info) |
{ |
int i; |
|
/* |
* Check if the name is non-empty and is composed solely of ASCII |
* characters [a-z]+[a-z0-9_-]*. |
*/ |
if (!islower(info->name[0])) { |
dprintf("The name doesn't start with a lowercase character.\n"); |
return false; |
} |
for (i = 1; i < FS_NAME_MAXLEN; i++) { |
if (!(islower(info->name[i]) || isdigit(info->name[i])) && |
(info->name[i] != '-') && (info->name[i] != '_')) { |
if (info->name[i] == '\0') { |
break; |
} else { |
dprintf("The name contains illegal " |
"characters.\n"); |
return false; |
} |
} |
} |
|
|
/* |
* Check if the FS implements mandatory VFS operations. |
*/ |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_REGISTER)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_REGISTER not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_MOUNT not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_UNMOUNT not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_LOOKUP not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_OPEN)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_OPEN not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_CLOSE)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_CLOSE not defined by the client.\n"); |
return false; |
} |
if (info->ops[IPC_METHOD_TO_VFS_OP(VFS_READ)] != VFS_OP_DEFINED) { |
dprintf("Operation VFS_READ not defined by the client.\n"); |
return false; |
} |
|
/* |
* Check if each operation is either not defined, defined or default. |
*/ |
for (i = VFS_FIRST; i < VFS_LAST; i++) { |
if ((info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_NULL) && |
(info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_DEFAULT) && |
(info->ops[IPC_METHOD_TO_VFS_OP(i)] != VFS_OP_DEFINED)) { |
dprintf("Operation info not understood.\n"); |
return false; |
} |
} |
return true; |
} |
|
/** VFS_REGISTER protocol function. |
* |
* @param rid Hash of the call with the request. |
* @param request Call structure with the request. |
*/ |
void vfs_register(ipc_callid_t rid, ipc_call_t *request) |
{ |
ipc_callid_t callid; |
ipc_call_t call; |
int rc; |
size_t size; |
|
dprintf("Processing VFS_REGISTER request received from %p.\n", |
request->in_phone_hash); |
|
/* |
* The first call has to be IPC_M_DATA_SEND in which we receive the |
* VFS info structure from the client FS. |
*/ |
if (!ipc_data_receive(&callid, &call, NULL, &size)) { |
/* |
* The client doesn't obey the same protocol as we do. |
*/ |
dprintf("Receiving of VFS info failed.\n"); |
ipc_answer_fast(callid, EINVAL, 0, 0); |
ipc_answer_fast(rid, EINVAL, 0, 0); |
return; |
} |
|
dprintf("VFS info received, size = %d\n", size); |
|
/* |
* We know the size of the VFS info structure. See if the client |
* understands this easy concept too. |
*/ |
if (size != sizeof(vfs_info_t)) { |
/* |
* The client is sending us something, which cannot be |
* the info structure. |
*/ |
dprintf("Received VFS info has bad size.\n"); |
ipc_answer_fast(callid, EINVAL, 0, 0); |
ipc_answer_fast(rid, EINVAL, 0, 0); |
return; |
} |
fs_info_t *fs_info; |
|
/* |
* Allocate and initialize a buffer for the fs_info structure. |
*/ |
fs_info = (fs_info_t *) malloc(sizeof(fs_info_t)); |
if (!fs_info) { |
dprintf("Could not allocate memory for FS info.\n"); |
ipc_answer_fast(callid, ENOMEM, 0, 0); |
ipc_answer_fast(rid, ENOMEM, 0, 0); |
return; |
} |
link_initialize(&fs_info->fs_link); |
|
rc = ipc_data_deliver(callid, &call, &fs_info->vfs_info, size); |
if (rc != EOK) { |
dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n", |
rc); |
free(fs_info); |
ipc_answer_fast(callid, rc, 0, 0); |
ipc_answer_fast(rid, rc, 0, 0); |
return; |
} |
|
dprintf("VFS info delivered.\n"); |
|
if (!vfs_info_sane(&fs_info->vfs_info)) { |
free(fs_info); |
ipc_answer_fast(callid, EINVAL, 0, 0); |
ipc_answer_fast(rid, EINVAL, 0, 0); |
return; |
} |
|
futex_down(&fs_head_futex); |
|
/* |
* Check for duplicit registrations. |
*/ |
link_t *cur; |
for (cur = fs_head.next; cur != &fs_head; cur = cur->next) { |
fs_info_t *fi = list_get_instance(cur, fs_info_t, |
fs_link); |
/* TODO: replace strcmp with strncmp once we have it */ |
if (strcmp(fs_info->vfs_info.name, fi->vfs_info.name) == 0) { |
/* |
* We already register a fs like this. |
*/ |
dprintf("FS is already registered.\n"); |
futex_up(&fs_head_futex); |
free(fs_info); |
ipc_answer_fast(callid, EEXISTS, 0, 0); |
ipc_answer_fast(rid, EEXISTS, 0, 0); |
return; |
} |
} |
|
/* |
* Add fs_info to the list of registered FS's. |
*/ |
dprintf("Adding FS into the registered list.\n"); |
list_append(&fs_info->fs_link, &fs_head); |
|
/* |
* ACK receiving a properly formatted, non-duplicit vfs_info. |
*/ |
ipc_answer_fast(callid, EOK, 0, 0); |
|
/* |
* Now we want the client to send us the IPC_M_CONNECT_TO_ME call so |
* that a callback connection is created and we have a phone through |
* which to forward VFS requests to it. |
*/ |
callid = async_get_call(&call); |
if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) { |
dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call)); |
list_remove(&fs_info->fs_link); |
futex_up(&fs_head_futex); |
free(fs_info); |
ipc_answer_fast(callid, EINVAL, 0, 0); |
ipc_answer_fast(rid, EINVAL, 0, 0); |
return; |
} |
fs_info->phone = IPC_GET_ARG3(call); |
ipc_answer_fast(callid, EOK, 0, 0); |
|
dprintf("Callback connection to FS created.\n"); |
|
futex_up(&fs_head_futex); |
|
/* |
* That was it. The FS has been registered. |
*/ |
ipc_answer_fast(rid, EOK, 0, 0); |
dprintf("\"%s\" filesystem successfully registered.\n", |
fs_info->vfs_info.name); |
} |
|
/** |
* @} |
*/ |