| 0,0 → 1,332 |
|---|
| /* |
| * 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 */ |
| char component[NAME_MAX + 1]; |
| int len; |
| |
| if (last < next) |
| last += PLB_SIZE; |
| |
| void *par = NULL; |
| void *cur = ops->root_get(dev_handle); |
| void *tmp = NULL; |
| |
| if (ops->plb_get_char(next) == '/') |
| next++; /* eat slash */ |
| |
| while (ops->has_children(cur) && next <= last) { |
| /* collect the component */ |
| len = 0; |
| while ((ops->plb_get_char(next) != '/') && (next <= last)) { |
| if (len + 1 == NAME_MAX) { |
| /* comopnent length overflow */ |
| ipc_answer_0(rid, ENAMETOOLONG); |
| goto out; |
| } |
| component[len++] = ops->plb_get_char(next); |
| next++; /* process next character */ |
| } |
| |
| assert(len); |
| component[len] = '\0'; |
| next++; /* eat slash */ |
| |
| /* match the component */ |
| tmp = ops->match(cur, component); |
| |
| /* handle miss: match amongst siblings */ |
| if (!tmp) { |
| if (next <= last) { |
| /* there are unprocessed components */ |
| ipc_answer_0(rid, ENOENT); |
| goto out; |
| } |
| /* 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); |
| goto out; |
| } |
| void *nodep; |
| if (lflag & L_CREATE) |
| nodep = ops->create(lflag); |
| else |
| nodep = ops->node_get(dev_handle, |
| index); |
| if (nodep) { |
| if (!ops->link(cur, nodep, component)) { |
| if (lflag & L_CREATE) |
| (void)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)); |
| ops->node_put(nodep); |
| } |
| } else { |
| ipc_answer_0(rid, ENOSPC); |
| } |
| goto out; |
| } 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); |
| goto out; |
| } |
| |
| if (par) |
| ops->node_put(par); |
| |
| /* descend one level */ |
| par = cur; |
| cur = tmp; |
| tmp = NULL; |
| } |
| |
| /* handle miss: excessive components */ |
| if (!ops->has_children(cur) && next <= last) { |
| if (lflag & (L_CREATE | L_LINK)) { |
| if (!ops->is_directory(cur)) { |
| ipc_answer_0(rid, ENOTDIR); |
| goto out; |
| } |
| |
| /* collect next component */ |
| len = 0; |
| while (next <= last) { |
| if (ops->plb_get_char(next) == '/') { |
| /* more than one component */ |
| ipc_answer_0(rid, ENOENT); |
| goto out; |
| } |
| if (len + 1 == NAME_MAX) { |
| /* component length overflow */ |
| ipc_answer_0(rid, ENAMETOOLONG); |
| goto out; |
| } |
| component[len++] = ops->plb_get_char(next); |
| next++; /* process next character */ |
| } |
| assert(len); |
| component[len] = '\0'; |
| |
| void *nodep; |
| if (lflag & L_CREATE) |
| nodep = ops->create(lflag); |
| else |
| nodep = ops->node_get(dev_handle, index); |
| if (nodep) { |
| if (!ops->link(cur, nodep, component)) { |
| if (lflag & L_CREATE) |
| (void)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)); |
| ops->node_put(nodep); |
| } |
| } else { |
| ipc_answer_0(rid, ENOSPC); |
| } |
| goto out; |
| } |
| ipc_answer_0(rid, ENOENT); |
| goto out; |
| } |
| |
| /* handle hit */ |
| if (lflag & L_PARENT) { |
| ops->node_put(cur); |
| cur = par; |
| par = NULL; |
| if (!cur) { |
| ipc_answer_0(rid, ENOENT); |
| goto out; |
| } |
| } |
| 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); |
| goto out; |
| } |
| if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) || |
| (lflag & L_LINK)) { |
| ipc_answer_0(rid, EEXIST); |
| goto out; |
| } |
| if ((lflag & L_FILE) && (ops->is_directory(cur))) { |
| ipc_answer_0(rid, EISDIR); |
| goto out; |
| } |
| if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) { |
| ipc_answer_0(rid, ENOTDIR); |
| goto out; |
| } |
| |
| ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur), |
| ops->size_get(cur), ops->lnkcnt_get(cur)); |
| |
| out: |
| if (par) |
| ops->node_put(par); |
| if (cur) |
| ops->node_put(cur); |
| if (tmp) |
| ops->node_put(tmp); |
| } |
| |
| /** @} |
| */ |