source: trunk/kernel/syscalls/sys_pipe.c @ 674

Last change on this file since 674 was 670, checked in by alain, 4 years 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: 5.7 KB
Line 
1/*
2 * sys_pipe.c - open a pipe communication channel
3 *
4 * Author    Alain Greiner  (2016,1017,2018,2019,2020)
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 <hal_kernel_types.h>
25#include <vfs.h>
26#include <hal_uspace.h>
27#include <process.h>
28#include <thread.h>
29#include <printk.h>
30#include <pipe.h>
31
32#include <syscalls.h>
33
34////////////////////////////
35int sys_pipe ( fdid_t * fd )
36{
37    vseg_t       * vseg;
38    kmem_req_t     req;
39    pipe_t       * pipe;
40    vfs_file_t   * file_0;
41    vfs_file_t   * file_1;
42    fdid_t         fdid_0;
43    fdid_t         fdid_1;
44    error_t        error;
45
46    thread_t     * this    = CURRENT_THREAD;
47    process_t    * process = this->process;
48
49#if DEBUG_SYS_PIPE || DEBUG_SYSCALLS_ERROR || CONFIG_INSTRUMENTATION_SYSCALLS
50uint64_t   tm_start = hal_get_cycles();
51#endif
52
53#if DEBUG_SYS_PIPE
54if( DEBUG_SYS_PIPE < tm_end )
55printk("\n[%s] thread[%x,%x] enter for <%s> / cycle %d\n",
56__FUNCTION__, process->pid, this->trdid, pathname, (uint32_t)tm_end );
57#endif
58
59    // check user buffer is mapped
60    if( vmm_get_vseg( process , (intptr_t)fd , &vseg ) )
61    {
62
63#if DEBUG_SYSCALLS_ERROR
64if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
65printk("\n[ERROR] in %s : thread[%x,%x] / output user buffer unmapped %x\n",
66__FUNCTION__ , process->pid, this->trdid, (intptr_t)fd );
67#endif
68                this->errno = EINVAL;
69                return -1;
70    }
71
72    // 1. allocate memory in local cluster for pipe descriptor,
73    //    remote buf_descriptor, and associated data buffer
74    pipe = pipe_create( local_cxy,
75                        CONFIG_PIPE_BUF_SIZE );
76
77    if( pipe == NULL )
78    {
79
80#if DEBUG_SYSCALLS_ERROR
81if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
82printk("\n[ERROR] in %s : thread[%x,%x] / no memory for pipe\n",
83__FUNCTION__ , process->pid, this->trdid );
84#endif
85        goto error_1;
86    }
87
88    // 2. allocate memory for fd[0] file descriptor in local cluster
89    // we don't use the vfs_file_create function because there is no inode.
90        req.type  = KMEM_KCM;
91        req.order = bits_log2( sizeof(vfs_file_t) );
92    req.flags = AF_ZERO;
93        file_0    = kmem_alloc( &req );
94
95    if( file_0 == NULL ) 
96    {
97
98#if DEBUG_SYSCALLS_ERROR
99if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
100printk("\n[ERROR] in %s : thread[%x,%x] / no memory for file descriptor\n",
101__FUNCTION__, process->pid, this->trdid );
102#endif
103        goto error_2;
104    }
105   
106    // 3. get fd[0] fdid value and register it in owner process fd_array[]
107    error = process_fd_register( process->owner_xp,
108                                 XPTR( local_cxy , file_0 ),
109                                 &fdid_0 );
110    if ( error )
111    {
112
113#if DEBUG_SYSCALLS_ERROR
114if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
115printk("\n[ERROR] in %s : thread[%x,%x] / cannot register file descriptor \n",
116__FUNCTION__, process->pid, this->trdid );
117#endif
118        goto error_3;
119    }
120
121    // 4. allocate memory for fd[1] file descriptor in local cluster
122        req.type  = KMEM_KCM;
123        req.order = bits_log2( sizeof(vfs_file_t) );
124    req.flags = AF_ZERO;
125        file_1    = kmem_alloc( &req );
126
127    if( file_1 == NULL ) 
128    {
129
130#if DEBUG_SYSCALLS_ERROR
131if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
132printk("\n[ERROR] in %s : thread[%x,%x] / no memory for file descriptor\n",
133__FUNCTION__, process->pid, this->trdid );
134#endif
135        goto error_4;
136    }
137
138    // 5. get fd[1] fdid value and register it in owner process fd_array[]
139    error = process_fd_register( process->owner_xp,
140                                 XPTR( local_cxy , file_1 ),
141                                 &fdid_1 );
142    if ( error )
143    {
144
145#if DEBUG_SYSCALLS_ERROR
146if( DEBUG_SYSCALLS_ERROR < (uint32_t)tm_start )
147printk("\n[ERROR] in %s : thread[%x,%x] / cannot register file descriptor \n",
148__FUNCTION__, process->pid, this->trdid );
149#endif
150        goto error_5;
151    }
152
153    // link the two file descriptors to the pipe
154    file_0->pipe = pipe;
155    file_1->pipe = pipe;
156
157    // copy fdid_0 & fdid_1 values to user buffer
158    hal_copy_to_uspace( &fd[0] , XPTR( local_cxy , &fdid_0 ) , sizeof(fdid_t) );
159    hal_copy_to_uspace( &fd[1] , XPTR( local_cxy , &fdid_1 ) , sizeof(fdid_t) );
160
161#if (DEBUG_SYS_PIPE || CONFIG_INSTRUMENTATION_SYSCALLS)
162uint64_t     tm_end = hal_get_cycles();
163#endif
164
165#if DEBUG_SYS_PIPE
166if( DEBUG_SYS_PIPE < tm_end )
167printk("\n[%s] thread[%x,%x] exit for <%s> / cycle %d\n",
168__FUNCTION__, this->process->pid, this->trdid, pathname, (uint32_t)tm_end );
169#endif
170 
171#if CONFIG_INSTRUMENTATION_SYSCALLS
172hal_atomic_add( &syscalls_cumul_cost[SYS_PIPE] , tm_end - tm_start );
173hal_atomic_add( &syscalls_occurences[SYS_PIPE] , 1 );
174#endif
175
176    return 0;
177
178error_5:    // release memory allocated for fd[1] file descriptor
179
180    req.ptr = file_1;
181    kmem_free( &req );
182
183error_4:    // release fdid_0 from fd_array[]
184
185    process_fd_remove( process->ref_xp , fdid_0 );
186
187error_3:    // release memory allocated for fd[0] file descriptor
188
189    req.ptr = file_0;
190    kmem_free( &req );
191
192error_2:    // release memory allocated for the pipe
193
194    pipe_destroy( XPTR( local_cxy , pipe ) );
195
196error_1:   // set errno and return error
197
198    this->errno = ENOMEM;
199    return -1;
200
201}  // end sys_pipe()
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