0,0 → 1,322 |
/* |
* Copyright (c) 2008 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 libfs |
* @{ |
*/ |
/** |
* @file |
* Glue code which is commonod to all FS implementations. |
*/ |
|
#include "libfs.h" |
#include "../../srv/vfs/vfs.h" |
#include <errno.h> |
#include <async.h> |
#include <ipc/ipc.h> |
#include <as.h> |
#include <assert.h> |
#include <dirent.h> |
|
/** Register file system server. |
* |
* This function abstracts away the tedious registration protocol from |
* file system implementations and lets them to reuse this registration glue |
* code. |
* |
* @param vfs_phone Open phone for communication with VFS. |
* @param reg File system registration structure. It will be |
* initialized by this function. |
* @param info VFS info structure supplied by the file system |
* implementation. |
* @param conn Connection fibril for handling all calls originating in |
* VFS. |
* |
* @return EOK on success or a non-zero error code on errror. |
*/ |
int fs_register(int vfs_phone, fs_reg_t *reg, vfs_info_t *info, |
async_client_conn_t conn) |
{ |
/* |
* Tell VFS that we are here and want to get registered. |
* We use the async framework because VFS will answer the request |
* out-of-order, when it knows that the operation succeeded or failed. |
*/ |
ipc_call_t answer; |
aid_t req = async_send_0(vfs_phone, VFS_REGISTER, &answer); |
|
/* |
* Send our VFS info structure to VFS. |
*/ |
int rc = ipc_data_write_start(vfs_phone, info, sizeof(*info)); |
if (rc != EOK) { |
async_wait_for(req, NULL); |
return rc; |
} |
|
/* |
* Ask VFS for callback connection. |
*/ |
ipc_connect_to_me(vfs_phone, 0, 0, 0, ®->vfs_phonehash); |
|
/* |
* Allocate piece of address space for PLB. |
*/ |
reg->plb_ro = as_get_mappable_page(PLB_SIZE); |
if (!reg->plb_ro) { |
async_wait_for(req, NULL); |
return ENOMEM; |
} |
|
/* |
* Request sharing the Path Lookup Buffer with VFS. |
*/ |
rc = ipc_share_in_start_0_0(vfs_phone, reg->plb_ro, PLB_SIZE); |
if (rc) { |
async_wait_for(req, NULL); |
return rc; |
} |
|
/* |
* Pick up the answer for the request to the VFS_REQUEST call. |
*/ |
async_wait_for(req, NULL); |
reg->fs_handle = (int) IPC_GET_ARG1(answer); |
|
/* |
* Create a connection fibril to handle the callback connection. |
*/ |
async_new_connection(reg->vfs_phonehash, 0, NULL, conn); |
|
/* |
* Tell the async framework that other connections are to be handled by |
* the same connection fibril as well. |
*/ |
async_set_client_connection(conn); |
|
return IPC_GET_RETVAL(answer); |
} |
|
/** Lookup VFS triplet by name in the file system name space. |
* |
* The path passed in the PLB must be in the canonical file system path format |
* as returned by the canonify() function. |
* |
* @param ops libfs operations structure with function pointers to |
* file system implementation |
* @param fs_handle File system handle of the file system where to perform |
* the lookup. |
* @param rid Request ID of the VFS_LOOKUP request. |
* @param request VFS_LOOKUP request data itself. |
*/ |
void libfs_lookup(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid, |
ipc_call_t *request) |
{ |
unsigned next = IPC_GET_ARG1(*request); |
unsigned last = IPC_GET_ARG2(*request); |
dev_handle_t dev_handle = IPC_GET_ARG3(*request); |
int lflag = IPC_GET_ARG4(*request); |
fs_index_t index = IPC_GET_ARG5(*request); /* when L_LINK specified */ |
|
if (last < next) |
last += PLB_SIZE; |
|
void *par = NULL; |
void *cur = ops->root_get(); |
void *tmp = ops->child_get(cur); |
|
if (ops->plb_get_char(next) == '/') |
next++; /* eat slash */ |
|
char component[NAME_MAX + 1]; |
int len = 0; |
while (tmp && next <= last) { |
|
/* collect the component */ |
if (ops->plb_get_char(next) != '/') { |
if (len + 1 == NAME_MAX) { |
/* comopnent length overflow */ |
ipc_answer_0(rid, ENAMETOOLONG); |
return; |
} |
component[len++] = ops->plb_get_char(next); |
next++; /* process next character */ |
if (next <= last) |
continue; |
} |
|
assert(len); |
component[len] = '\0'; |
next++; /* eat slash */ |
len = 0; |
|
/* match the component */ |
while (tmp && !ops->match(cur, tmp, component)) |
tmp = ops->sibling_get(tmp); |
|
/* handle miss: match amongst siblings */ |
if (!tmp) { |
if (next <= last) { |
/* there are unprocessed components */ |
ipc_answer_0(rid, ENOENT); |
return; |
} |
/* miss in the last component */ |
if (lflag & (L_CREATE | L_LINK)) { |
/* request to create a new link */ |
if (!ops->is_directory(cur)) { |
ipc_answer_0(rid, ENOTDIR); |
return; |
} |
void *nodep; |
if (lflag & L_CREATE) |
nodep = ops->create(lflag); |
else |
nodep = ops->node_get(fs_handle, |
dev_handle, index); |
if (nodep) { |
if (!ops->link(cur, nodep, component)) { |
if (lflag & L_CREATE) |
ops->destroy(nodep); |
ipc_answer_0(rid, ENOSPC); |
} else { |
ipc_answer_5(rid, EOK, |
fs_handle, dev_handle, |
ops->index_get(nodep), |
ops->size_get(nodep), |
ops->lnkcnt_get(nodep)); |
} |
} else { |
ipc_answer_0(rid, ENOSPC); |
} |
return; |
} else if (lflag & L_PARENT) { |
/* return parent */ |
ipc_answer_5(rid, EOK, fs_handle, dev_handle, |
ops->index_get(cur), ops->size_get(cur), |
ops->lnkcnt_get(cur)); |
} |
ipc_answer_0(rid, ENOENT); |
return; |
} |
|
/* descend one level */ |
par = cur; |
cur = tmp; |
tmp = ops->child_get(tmp); |
} |
|
/* handle miss: excessive components */ |
if (!tmp && next <= last) { |
if (lflag & (L_CREATE | L_LINK)) { |
if (!ops->is_directory(cur)) { |
ipc_answer_0(rid, ENOTDIR); |
return; |
} |
|
/* collect next component */ |
while (next <= last) { |
if (ops->plb_get_char(next) == '/') { |
/* more than one component */ |
ipc_answer_0(rid, ENOENT); |
return; |
} |
if (len + 1 == NAME_MAX) { |
/* component length overflow */ |
ipc_answer_0(rid, ENAMETOOLONG); |
return; |
} |
component[len++] = ops->plb_get_char(next); |
next++; /* process next character */ |
} |
assert(len); |
component[len] = '\0'; |
len = 0; |
|
void *nodep; |
if (lflag & L_CREATE) |
nodep = ops->create(lflag); |
else |
nodep = ops->node_get(fs_handle, dev_handle, |
index); |
if (nodep) { |
if (!ops->link(cur, nodep, component)) { |
if (lflag & L_CREATE) |
ops->destroy(nodep); |
ipc_answer_0(rid, ENOSPC); |
} else { |
ipc_answer_5(rid, EOK, |
fs_handle, dev_handle, |
ops->index_get(nodep), |
ops->size_get(nodep), |
ops->lnkcnt_get(nodep)); |
} |
} else { |
ipc_answer_0(rid, ENOSPC); |
} |
return; |
} |
ipc_answer_0(rid, ENOENT); |
return; |
} |
|
/* handle hit */ |
if (lflag & L_PARENT) { |
cur = par; |
if (!cur) { |
ipc_answer_0(rid, ENOENT); |
return; |
} |
} |
if (lflag & L_UNLINK) { |
unsigned old_lnkcnt = ops->lnkcnt_get(cur); |
int res = ops->unlink(par, cur); |
ipc_answer_5(rid, (ipcarg_t)res, fs_handle, dev_handle, |
ops->index_get(cur), ops->size_get(cur), old_lnkcnt); |
return; |
} |
if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) || |
(lflag & L_LINK)) { |
ipc_answer_0(rid, EEXIST); |
return; |
} |
if ((lflag & L_FILE) && (ops->is_directory(cur))) { |
ipc_answer_0(rid, EISDIR); |
return; |
} |
if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) { |
ipc_answer_0(rid, ENOTDIR); |
return; |
} |
|
ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur), |
ops->size_get(cur), ops->lnkcnt_get(cur)); |
} |
|
/** @} |
*/ |