source: trunk/kernel/syscalls/sys_write.c @ 459

Last change on this file since 459 was 459, checked in by alain, 3 years ago

Introduce the math library, to support the floating point
data used by the multi-thread fft application.
Fix several bugs regarding the FPU context save/restore.
Introduce support for the %f format in printf.

File size: 7.7 KB
Line 
1/*
2 * sys_write.c - write bytes to a file
3 *
4 * Author        Alain Greiner (2016,2017,2018)
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_irqmask.h>
28#include <hal_special.h>
29#include <errno.h>
30#include <vfs.h>
31#include <thread.h>
32#include <printk.h>
33#include <process.h>
34
35/* TODO: concurrent user page(s) unmap need to be handled [AG] */
36
37extern uint32_t enter_sys_write;
38extern uint32_t enter_devfs_write;
39extern uint32_t enter_txt_write;
40extern uint32_t enter_chdev_cmd_write;
41extern uint32_t enter_chdev_server_write;
42extern uint32_t enter_tty_cmd_write;
43extern uint32_t enter_tty_isr_write;
44extern uint32_t exit_tty_isr_write;
45extern uint32_t exit_tty_cmd_write;
46extern uint32_t exit_chdev_server_write;
47extern uint32_t exit_chdev_cmd_write;
48extern uint32_t exit_txt_write;
49extern uint32_t exit_devfs_write;
50extern uint32_t exit_sys_write;
51
52//////////////////////////////////
53int sys_write( uint32_t   file_id,
54               void     * vaddr,
55               uint32_t   count )
56{
57    error_t      error;
58    vseg_t     * vseg;            // required for user space checking
59        xptr_t       file_xp;         // remote file extended pointer
60    uint32_t     nbytes;          // number of bytes actually written
61    reg_t        save_sr;         // required to enable IRQs during syscall
62
63#if (DEBUG_SYS_WRITE & 1)
64enter_sys_write = (uint32_t)tm_start;
65#endif
66
67        thread_t   * this = CURRENT_THREAD;
68        process_t  * process = this->process;
69
70#if DEBUG_SYS_WRITE
71uint32_t     tm_start;
72uint32_t     tm_end;
73tm_start = hal_get_cycles();
74if( DEBUG_SYS_WRITE < tm_start )
75printk("\n[DBG] %s : thread %x in process %x enter / vaddr %x / count %d / cycle %d\n",
76__FUNCTION__, this->trdid, process->pid, vaddr, count, (uint32_t)tm_start );
77#endif
78 
79    // check file_id argument
80        if( file_id >= CONFIG_PROCESS_FILE_MAX_NR )
81        {
82
83#if DEBUG_SYSCALLS_ERROR
84printk("\n[ERROR] in %s : illegal file descriptor index\n", __FUNCTION__ );
85#endif
86        this->errno = EBADFD;
87                return -1;
88        }
89
90    // check user buffer in user space
91    error = vmm_get_vseg( process , (intptr_t)vaddr , &vseg );
92
93    if ( error )
94    {
95
96#if DEBUG_SYSCALLS_ERROR
97printk("\n[ERROR] in %s : user buffer unmapped %x / thread %x / process %x\n",
98__FUNCTION__ , (intptr_t)vaddr, this->trdid, process->pid );
99vmm_display( process , false );
100#endif
101                this->errno = EINVAL;
102                return -1;
103    }
104
105    // get extended pointer on remote file descriptor
106    file_xp = process_fd_get_xptr( process , file_id );
107
108    if( file_xp == XPTR_NULL )
109    {
110
111#if DEBUG_SYSCALLS_ERROR
112printk("\n[ERROR] in %s : undefined file descriptor index = %d in process %x\n",
113__FUNCTION__ , file_id , process->pid );
114#endif
115                this->errno = EBADFD;
116                return -1;
117    }
118
119    // get file descriptor cluster and local pointer
120    vfs_file_t * file_ptr = (vfs_file_t *)GET_PTR( file_xp );
121    cxy_t        file_cxy = GET_CXY( file_xp );
122
123 
124    // get file type
125    vfs_inode_type_t type = hal_remote_lw( XPTR( file_cxy , &file_ptr->type ) );
126
127    // enable IRQs
128    hal_enable_irq( &save_sr );
129
130   // action depend on file type
131    if( type == INODE_TYPE_FILE )  // check file writable & write to mapper
132    {
133        // check file writable
134        uint32_t attr = hal_remote_lw( XPTR( file_cxy , &file_ptr->attr ) );
135        if( (attr & FD_ATTR_WRITE_ENABLE) == 0 )
136            {
137
138#if DEBUG_SYSCALLS_ERROR
139printk("\n[ERROR] in %s : file %d not writable in process %x\n",
140__FUNCTION__ , file_id , process->pid );
141#endif
142                    this->errno = EBADFD;
143                    return -1;
144            }
145
146        // move count bytes to mapper
147        nbytes = vfs_user_move( false,               // from buffer to mapper
148                                file_xp,
149                                vaddr, 
150                                count );
151    }
152    else if( type == INODE_TYPE_DEV )  // check ownership & write to device
153    {
154        // check user buffer size for TXT_TX
155        if( (type == INODE_TYPE_DEV) && (count >= CONFIG_TXT_KBUF_SIZE) )
156        {
157
158#if DEBUG_SYSCALLS_ERROR
159printk("\n[ERROR] in %s : user buffer size %x too large / thread %x / process %x\n",
160__FUNCTION__ , count, this->trdid, process->pid );
161#endif
162                    this->errno = EINVAL;
163                    return -1;
164        }
165
166        // move count bytes to device
167        nbytes = devfs_user_move( false,             // from buffer to device
168                                 file_xp,
169                                 vaddr,
170                                 count );
171    }
172    else  // not FILE and not DEV
173    {
174        nbytes = 0;
175        assert( false , __FUNCTION__ , "file type %d non supported\n", type );
176    }
177
178    if( nbytes != count )
179    {
180
181#if DEBUG_SYSCALLS_ERROR
182printk("\n[ERROR] in %s cannot write data to file %d in process %x\n",
183__FUNCTION__ , file_id , process->pid );
184#endif
185        this->errno = error;
186        return -1;
187    }
188
189    // restore IRQs
190    hal_restore_irq( save_sr );
191
192    hal_fence();
193
194#if DEBUG_SYS_WRITE
195tm_end = hal_get_cycles();
196if( DEBUG_SYS_WRITE < tm_end )
197printk("\n[DBG] %s : thread %x in process %x exit / cycle %d\n"
198"nbytes %d / file_id %d / cost %d\n",
199__FUNCTION__, this->trdid, process->pid, (uint32_t)tm_start,
200nbytes, file_id , (uint32_t)(tm_end - tm_start) );
201#endif
202 
203#if (DEBUG_SYS_WRITE & 1)
204exit_sys_write = (uint32_t)tm_end;
205
206printk("\n***** timing to write a string *****\n"
207" - enter_sys_write          = %d / delta %d\n"
208" - enter_devfs_write        = %d / delta %d\n"
209" - enter_txt_write          = %d / delta %d\n"
210" - enter_chdev_cmd_write    = %d / delta %d\n"
211" - enter_chdev_server_write = %d / delta %d\n"
212" - enter_tty_cmd_write      = %d / delta %d\n"
213" - enter_tty_isr_write      = %d / delta %d\n"
214" - exit_tty_isr_write       = %d / delta %d\n"
215" - exit_tty_cmd_write       = %d / delta %d\n"
216" - exit_chdev_server_write  = %d / delta %d\n"
217" - exit_chdev_cmd_write     = %d / delta %d\n"
218" - exit_txt_write           = %d / delta %d\n"
219" - exit_devfs_write         = %d / delta %d\n"
220" - exit_sys_write           = %d / delta %d\n",
221enter_sys_write          , 0 ,
222enter_devfs_write        , enter_devfs_write        - enter_sys_write          ,
223enter_txt_write          , enter_txt_write          - enter_devfs_write        ,
224enter_chdev_cmd_write    , enter_chdev_cmd_write    - enter_txt_write          ,
225enter_chdev_server_write , enter_chdev_server_write - enter_chdev_cmd_write    ,
226enter_tty_cmd_write      , enter_tty_cmd_write      - enter_chdev_server_write ,
227enter_tty_isr_write      , enter_tty_isr_write      - enter_tty_cmd_write      ,
228exit_tty_isr_write       , exit_tty_isr_write       - enter_tty_isr_write      ,
229exit_tty_cmd_write       , exit_tty_cmd_write       - exit_tty_isr_write       ,
230exit_chdev_server_write  , exit_chdev_server_write  - exit_tty_cmd_write       ,
231exit_chdev_cmd_write     , exit_chdev_cmd_write     - exit_chdev_server_write  ,
232exit_txt_write           , exit_txt_write           - exit_chdev_cmd_write     ,
233exit_devfs_write         , exit_devfs_write         - exit_txt_write           ,
234exit_sys_write           , exit_sys_write           - exit_devfs_write         );
235#endif
236 
237        return nbytes;
238
239}  // end sys_write()
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