source: trunk/kernel/syscalls/sys_opendir.c @ 670

Last change on this file since 670 was 670, checked in by alain, 18 months ago

1) Introduce up to 4 command lines arguments in the KSH "load" command.
These arguments are transfered to the user process through the
argc/argv mechanism, using the user space "args" vseg.

2) Introduce the named and anonymous "pipes", for inter-process communication
through the pipe() and mkfifo() syscalls.

3) Introduce the "chat" application to validate the two above mechanisms.

4) Improve printk() and assert() fonctions in printk.c.

File size: 6.8 KB
Line 
1/*
2 * sys_opendir.c - Open an user accessible VFS directory.
3 *
4 * Author        Alain Greiner (2016,2017,2018,2019,2020)
5 *
6 * Copyright (c) UPMC Sorbonne Universites
7 *
8 * This file is part of ALMOS-MKH.
9 *
10 * ALMOS-MKH is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; version 2.0 of the License.
13 *
14 * ALMOS-MKH is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with ALMOS-MKH; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#include <kernel_config.h>
25#include <hal_kernel_types.h>
26#include <hal_uspace.h>
27#include <hal_vmm.h>
28#include <thread.h>
29#include <process.h>
30#include <user_dir.h>
31#include <printk.h>
32#include <errno.h>
33#include <vseg.h>
34#include <vfs.h>
35#include <syscalls.h>
36#include <shared_syscalls.h>
37
38///////////////////////////////////
39int sys_opendir ( char *  pathname,
40                  DIR  ** dirp )
41{
42    error_t        error;
43    xptr_t         root_inode_xp;          // extended pointer on path root inode
44    xptr_t         inode_xp;               // extended pointer on directory inode
45    vfs_inode_t  * inode_ptr;              // local pointer on directory inode
46    cxy_t          inode_cxy;              // directory inode cluster
47    uint32_t       inode_type;             // to check directory inode type
48    user_dir_t   * dir_ptr;                // local pointer on user_dir_t
49    vseg_t       * vseg;                   // for user space checking
50    intptr_t       ident;                  // dirent array pointer in user space                 
51    char          kbuf[CONFIG_VFS_MAX_PATH_LENGTH];
52       
53        thread_t     * this    = CURRENT_THREAD;  // client thread
54        process_t    * process = this->process;   // client process
55
56#if DEBUG_SYS_OPENDIR || DEBUG_SYSCALLS_ERROR || CONFIG_INSTRUMENTATION_SYSCALLS
57uint64_t     tm_start = hal_get_cycles();
58#endif
59
60    // check DIR buffer in user space
61    error = vmm_get_vseg( process , (intptr_t)dirp, &vseg );
62
63        if( error )
64        {
65
66#if DEBUG_SYSCALLS_ERROR
67if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
68printk("\n[ERROR] in %s : thread[%x,%x] / DIR buffer %x unmapped\n",
69__FUNCTION__ , process->pid , this->trdid, dirp );
70#endif
71                this->errno = EINVAL;
72                return -1;
73        }       
74
75    // check pathname in user space
76    error = vmm_get_vseg( process , (intptr_t)pathname, &vseg );
77
78        if( error )
79        {
80
81#if DEBUG_SYSCALLS_ERROR
82if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
83printk("\n[ERROR] in %s : thread[%x,%x] / pathname %x unmapped\n",
84__FUNCTION__ , process->pid , this->trdid, pathname );
85#endif
86                this->errno = EINVAL;
87                return -1;
88        }       
89    // check pathname length
90    if( hal_strlen_from_uspace( pathname ) >= CONFIG_VFS_MAX_PATH_LENGTH )
91    {
92
93#if DEBUG_SYSCALLS_ERROR
94if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
95printk("\n[ERROR] in %s / thread[%x,%x] : pathname too long\n",
96 __FUNCTION__ , process->pid , this->trdid );
97#endif
98        this->errno = ENFILE;
99        return -1;
100    }
101
102    // copy pathname in kernel space
103    hal_strcpy_from_uspace( XPTR( local_cxy , kbuf ),
104                            pathname,
105                            CONFIG_VFS_MAX_PATH_LENGTH );
106
107#if DEBUG_SYS_OPENDIR
108if( DEBUG_SYS_OPENDIR < (uint32_t)tm_start )
109printk("\n[%s] thread[%x,%x] enter for directory <%s> / cycle %d\n",
110__FUNCTION__, process->pid, this->trdid, kbuf, (uint32_t)tm_start );
111#endif
112
113    // compute root inode for pathname
114    if( kbuf[0] == '/' )                        // absolute path
115    {
116        // use extended pointer on VFS root inode
117        root_inode_xp = process->vfs_root_xp;
118    }
119    else                                        // relative path
120    {
121        // get cluster and local pointer on reference process
122        xptr_t      ref_xp  = process->ref_xp;
123        process_t * ref_ptr = (process_t *)GET_PTR( ref_xp );
124        cxy_t       ref_cxy = GET_CXY( ref_xp );
125
126        // use extended pointer on CWD inode
127        root_inode_xp = hal_remote_l64( XPTR( ref_cxy , &ref_ptr->cwd_xp ) );
128    }
129
130    // get extended pointer on directory inode
131    error = vfs_lookup( root_inode_xp,
132                        kbuf,
133                        0,
134                        &inode_xp,
135                        NULL );
136    if( error )
137        {
138
139#if DEBUG_SYSCALLS_ERROR
140if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
141printk("\n[ERROR] in %s : thread[%x,%x] / cannot found directory <%s>\n",
142__FUNCTION__ , process->pid , this->trdid , kbuf );
143#endif
144                this->errno = ENFILE;
145                return -1;
146        }
147   
148    // check inode type
149    inode_ptr  = GET_PTR( inode_xp );
150    inode_cxy  = GET_CXY( inode_xp );
151    inode_type = hal_remote_l32( XPTR( inode_cxy , &inode_ptr->type ) );
152
153    if( inode_type != FILE_TYPE_DIR )
154        {
155
156#if DEBUG_SYSCALLS_ERROR
157if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
158printk("\n[ERROR] in %s : thread[%x,%x] / <%s> is not a directory\n",
159__FUNCTION__ , process->pid , this->trdid , kbuf );
160#endif
161                this->errno = ENFILE;
162                return -1;
163        }
164   
165    // create a new user_dir_t structure in target directory inode cluster
166    // map it in the reference user process VMM (in a new ANON vseg)
167    // an get the local pointer on the created user_dir_t structure
168    if( inode_cxy == local_cxy )
169    {
170        dir_ptr = user_dir_create( inode_ptr,
171                                   process->ref_xp );
172    }
173    else
174    {
175        rpc_user_dir_create_client( inode_cxy,
176                                    inode_ptr,
177                                    process->ref_xp,
178                                    &dir_ptr );
179    }
180
181    if( dir_ptr == NULL )
182        {
183
184#if DEBUG_SYSCALLS_ERROR
185if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
186printk("\n[ERROR] in %s : thread[%x,%x] / cannot create user_dir for <%s>\n",
187__FUNCTION__ , process->pid , this->trdid , kbuf );
188#endif
189                this->errno = ENFILE;
190                return -1;
191        }
192   
193    // get ident from user_dir structure
194    ident = (intptr_t)hal_remote_lpt( XPTR( inode_cxy , &dir_ptr->ident ) );
195
196    // set ident value in user buffer
197    hal_copy_to_uspace( dirp,
198                        XPTR( local_cxy , &ident ),
199                        sizeof(intptr_t) );
200
201    hal_fence();
202
203#if (DEBUG_SYS_OPENDIR || CONFIG_INSTRUMENTATION_SYSCALLS)
204uint64_t     tm_end = hal_get_cycles();
205#endif
206
207#if DEBUG_SYS_OPENDIR
208if( DEBUG_SYS_OPENDIR < tm_end )
209printk("\n[%s] thread[%x,%x] exit for directory <%s> / cycle %d\n",
210__FUNCTION__, process->pid, this->trdid, kbuf, (uint32_t)tm_end );
211#endif
212 
213#if CONFIG_INSTRUMENTATION_SYSCALLS
214hal_atomic_add( &syscalls_cumul_cost[SYS_OPENDIR] , tm_end - tm_start );
215hal_atomic_add( &syscalls_occurences[SYS_OPENDIR] , 1 );
216#endif
217
218        return 0;
219
220}  // end sys_opendir()
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