| 1 | /* |
|---|
| 2 | * sys_read.c - read bytes from 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 <vmm.h> |
|---|
| 32 | #include <thread.h> |
|---|
| 33 | #include <printk.h> |
|---|
| 34 | #include <process.h> |
|---|
| 35 | |
|---|
| 36 | |
|---|
| 37 | extern uint32_t enter_sys_read; |
|---|
| 38 | extern uint32_t enter_devfs_read; |
|---|
| 39 | extern uint32_t enter_txt_read; |
|---|
| 40 | extern uint32_t enter_chdev_cmd_read; |
|---|
| 41 | extern uint32_t enter_chdev_server_read; |
|---|
| 42 | extern uint32_t enter_tty_cmd_read; |
|---|
| 43 | extern uint32_t enter_tty_isr_read; |
|---|
| 44 | extern uint32_t exit_tty_isr_read; |
|---|
| 45 | extern uint32_t exit_tty_cmd_read; |
|---|
| 46 | extern uint32_t exit_chdev_server_read; |
|---|
| 47 | extern uint32_t exit_chdev_cmd_read; |
|---|
| 48 | extern uint32_t exit_txt_read; |
|---|
| 49 | extern uint32_t exit_devfs_read; |
|---|
| 50 | extern uint32_t exit_sys_read; |
|---|
| 51 | |
|---|
| 52 | |
|---|
| 53 | ///////////////////////////////// |
|---|
| 54 | int sys_read( uint32_t file_id, |
|---|
| 55 | void * vaddr, |
|---|
| 56 | uint32_t count ) |
|---|
| 57 | { |
|---|
| 58 | error_t error; |
|---|
| 59 | vseg_t * vseg; // required for user space checking |
|---|
| 60 | xptr_t file_xp; // remote file extended pointer |
|---|
| 61 | uint32_t nbytes; // number of bytes actually read |
|---|
| 62 | reg_t save_sr; // required to enable IRQs during syscall |
|---|
| 63 | |
|---|
| 64 | thread_t * this = CURRENT_THREAD; |
|---|
| 65 | process_t * process = this->process; |
|---|
| 66 | xptr_t process_owner_xp = process->owner_xp; |
|---|
| 67 | |
|---|
| 68 | #if (DEBUG_SYS_READ || CONFIG_INSTRUMENTATION_SYSCALLS) |
|---|
| 69 | uint64_t tm_start = hal_get_cycles(); |
|---|
| 70 | #endif |
|---|
| 71 | |
|---|
| 72 | #if DEBUG_SYS_READ |
|---|
| 73 | if( DEBUG_SYS_READ < tm_start ) |
|---|
| 74 | printk("\n[DBG] %s : thread %x in process %x enter / vaddr %x / count %d / cycle %d\n", |
|---|
| 75 | __FUNCTION__, this->trdid, process->pid, vaddr, count, (uint32_t)tm_start ); |
|---|
| 76 | #endif |
|---|
| 77 | |
|---|
| 78 | #if (DEBUG_SYS_READ & 1) |
|---|
| 79 | enter_sys_read = (uint32_t)tm_start; |
|---|
| 80 | #endif |
|---|
| 81 | |
|---|
| 82 | // check file_id argument |
|---|
| 83 | if( file_id >= CONFIG_PROCESS_FILE_MAX_NR ) |
|---|
| 84 | { |
|---|
| 85 | |
|---|
| 86 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 87 | printk("\n[ERROR] in %s : illegal file descriptor index = %d\n", __FUNCTION__ , file_id ); |
|---|
| 88 | #endif |
|---|
| 89 | this->errno = EBADFD; |
|---|
| 90 | return -1; |
|---|
| 91 | } |
|---|
| 92 | |
|---|
| 93 | // check user buffer in user space |
|---|
| 94 | error = vmm_get_vseg( process , (intptr_t)vaddr , &vseg ); |
|---|
| 95 | |
|---|
| 96 | if ( error ) |
|---|
| 97 | { |
|---|
| 98 | |
|---|
| 99 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 100 | printk("\n[ERROR] in %s : user buffer unmapped %x / thread %x / process %x\n", |
|---|
| 101 | __FUNCTION__ , (intptr_t)vaddr, this->trdid, process->pid ); |
|---|
| 102 | vmm_display( process , false ); |
|---|
| 103 | #endif |
|---|
| 104 | this->errno = EINVAL; |
|---|
| 105 | return -1; |
|---|
| 106 | } |
|---|
| 107 | |
|---|
| 108 | // enable IRQs |
|---|
| 109 | hal_enable_irq( &save_sr ); |
|---|
| 110 | |
|---|
| 111 | // get extended pointer on remote file descriptor |
|---|
| 112 | file_xp = process_fd_get_xptr( process , file_id ); |
|---|
| 113 | |
|---|
| 114 | if( file_xp == XPTR_NULL ) |
|---|
| 115 | { |
|---|
| 116 | |
|---|
| 117 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 118 | printk("\n[ERROR] in %s : undefined fd_id %d in process %x\n", |
|---|
| 119 | __FUNCTION__ , file_id , process->pid ); |
|---|
| 120 | #endif |
|---|
| 121 | this->errno = EBADFD; |
|---|
| 122 | return -1; |
|---|
| 123 | } |
|---|
| 124 | |
|---|
| 125 | // get file descriptor cluster and local pointer |
|---|
| 126 | vfs_file_t * file_ptr = GET_PTR( file_xp ); |
|---|
| 127 | cxy_t file_cxy = GET_CXY( file_xp ); |
|---|
| 128 | |
|---|
| 129 | // check file readable |
|---|
| 130 | uint32_t attr = hal_remote_l32( XPTR( file_cxy , &file_ptr->attr ) ); |
|---|
| 131 | if( (attr & FD_ATTR_READ_ENABLE) == 0 ) |
|---|
| 132 | { |
|---|
| 133 | |
|---|
| 134 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 135 | printk("\n[ERROR] in %s : file %d not readable in process %x\n", |
|---|
| 136 | __FUNCTION__ , file_id , process->pid ); |
|---|
| 137 | #endif |
|---|
| 138 | this->errno = EBADFD; |
|---|
| 139 | return -1; |
|---|
| 140 | } |
|---|
| 141 | |
|---|
| 142 | // get file type |
|---|
| 143 | vfs_inode_type_t type = hal_remote_l32( XPTR( file_cxy , &file_ptr->type ) ); |
|---|
| 144 | |
|---|
| 145 | // action depend on file type |
|---|
| 146 | if( type == INODE_TYPE_FILE ) // check file readable & read from mapper |
|---|
| 147 | { |
|---|
| 148 | // check file readable |
|---|
| 149 | uint32_t attr = hal_remote_l32( XPTR( file_cxy , &file_ptr->attr ) ); |
|---|
| 150 | |
|---|
| 151 | if( (attr & FD_ATTR_READ_ENABLE) == 0 ) |
|---|
| 152 | { |
|---|
| 153 | |
|---|
| 154 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 155 | printk("\n[ERROR] in %s : file %d not readable in process %x\n", |
|---|
| 156 | __FUNCTION__ , file_id , process->pid ); |
|---|
| 157 | #endif |
|---|
| 158 | this->errno = EBADFD; |
|---|
| 159 | return -1; |
|---|
| 160 | } |
|---|
| 161 | |
|---|
| 162 | // move count bytes from mapper |
|---|
| 163 | nbytes = vfs_user_move( true, // from mapper to buffer |
|---|
| 164 | file_xp, |
|---|
| 165 | vaddr, |
|---|
| 166 | count ); |
|---|
| 167 | } |
|---|
| 168 | else if( type == INODE_TYPE_DEV ) // check ownership & read from device |
|---|
| 169 | { |
|---|
| 170 | // get cluster and pointers on TXT_RX chdev |
|---|
| 171 | xptr_t chdev_xp = chdev_from_file( file_xp ); |
|---|
| 172 | cxy_t chdev_cxy = GET_CXY( chdev_xp ); |
|---|
| 173 | chdev_t * chdev_ptr = GET_PTR( chdev_xp ); |
|---|
| 174 | |
|---|
| 175 | volatile xptr_t txt_owner_xp; |
|---|
| 176 | uint32_t iter = 0; |
|---|
| 177 | |
|---|
| 178 | while( 1 ) |
|---|
| 179 | { |
|---|
| 180 | // extended pointer on TXT owner process |
|---|
| 181 | txt_owner_xp = hal_remote_l64( XPTR( chdev_cxy , &chdev_ptr->ext.txt.owner_xp ) ); |
|---|
| 182 | |
|---|
| 183 | // check TXT_RX ownership |
|---|
| 184 | if ( process_owner_xp != txt_owner_xp ) |
|---|
| 185 | { |
|---|
| 186 | if( (iter & 0xFFF) == 0 ) |
|---|
| 187 | printk("\n[WARNING] in %s : thread %x in process %x wait TXT_RX / cycle %d\n", |
|---|
| 188 | __FUNCTION__, this->trdid, process->pid, (uint32_t)hal_get_cycles() ); |
|---|
| 189 | |
|---|
| 190 | // deschedule without blocking |
|---|
| 191 | sched_yield( "wait TXT_RX ownership" ); |
|---|
| 192 | |
|---|
| 193 | iter++; |
|---|
| 194 | } |
|---|
| 195 | else |
|---|
| 196 | { |
|---|
| 197 | break; |
|---|
| 198 | } |
|---|
| 199 | } |
|---|
| 200 | |
|---|
| 201 | // move count bytes from device |
|---|
| 202 | nbytes = devfs_user_move( true, // from device to buffer |
|---|
| 203 | file_xp, |
|---|
| 204 | vaddr, |
|---|
| 205 | count ); |
|---|
| 206 | |
|---|
| 207 | } |
|---|
| 208 | else |
|---|
| 209 | { |
|---|
| 210 | nbytes = 0; |
|---|
| 211 | assert( false , "file type %d non supported yet\n", type ); |
|---|
| 212 | } |
|---|
| 213 | |
|---|
| 214 | if( nbytes != count ) |
|---|
| 215 | { |
|---|
| 216 | |
|---|
| 217 | #if DEBUG_SYSCALLS_ERROR |
|---|
| 218 | printk("\n[ERROR] in %s cannot read data from file %d in process %x\n", |
|---|
| 219 | __FUNCTION__ , file_id , process->pid ); |
|---|
| 220 | #endif |
|---|
| 221 | this->errno = error; |
|---|
| 222 | return -1; |
|---|
| 223 | } |
|---|
| 224 | |
|---|
| 225 | // restore IRQs |
|---|
| 226 | hal_restore_irq( save_sr ); |
|---|
| 227 | |
|---|
| 228 | hal_fence(); |
|---|
| 229 | |
|---|
| 230 | #if (DEBUG_SYS_READ || CONFIG_INSTRUMENTATION_SYSCALLS) |
|---|
| 231 | uint64_t tm_end = hal_get_cycles(); |
|---|
| 232 | #endif |
|---|
| 233 | |
|---|
| 234 | #if DEBUG_SYS_READ |
|---|
| 235 | if( DEBUG_SYS_READ < tm_end ) |
|---|
| 236 | printk("\n[DBG] %s : thread %x in process %x exit / cycle %d\n", |
|---|
| 237 | __FUNCTION__ , this->trdid, process->pid, (uint32_t)tm_end ); |
|---|
| 238 | #endif |
|---|
| 239 | |
|---|
| 240 | #if CONFIG_INSTRUMENTATION_SYSCALLS |
|---|
| 241 | hal_atomic_add( &syscalls_cumul_cost[SYS_READ] , tm_end - tm_start ); |
|---|
| 242 | hal_atomic_add( &syscalls_occurences[SYS_READ] , 1 ); |
|---|
| 243 | #endif |
|---|
| 244 | |
|---|
| 245 | #if (DEBUG_SYS_READ & 1) |
|---|
| 246 | exit_sys_read = (uint32_t)tm_end; |
|---|
| 247 | |
|---|
| 248 | printk("\n***** timing to read one character *****\n" |
|---|
| 249 | " - enter_sys_read = %d / delta %d\n" |
|---|
| 250 | " - enter_devfs_read = %d / delta %d\n" |
|---|
| 251 | " - enter_txt_read = %d / delta %d\n" |
|---|
| 252 | " - enter_chdev_cmd_read = %d / delta %d\n" |
|---|
| 253 | " - enter_chdev_server_read = %d / delta %d\n" |
|---|
| 254 | " - enter_tty_cmd_read = %d / delta %d\n" |
|---|
| 255 | " - enter_tty_isr_read = %d / delta %d\n" |
|---|
| 256 | " - exit_tty_isr_read = %d / delta %d\n" |
|---|
| 257 | " - exit_tty_cmd_read = %d / delta %d\n" |
|---|
| 258 | " - exit_chdev_server_read = %d / delta %d\n" |
|---|
| 259 | " - exit_chdev_cmd_read = %d / delta %d\n" |
|---|
| 260 | " - exit_txt_read = %d / delta %d\n" |
|---|
| 261 | " - exit_devfs_read = %d / delta %d\n" |
|---|
| 262 | " - exit_sys_read = %d / delta %d\n", |
|---|
| 263 | enter_sys_read , 0 , |
|---|
| 264 | enter_devfs_read , enter_devfs_read - enter_sys_read , |
|---|
| 265 | enter_txt_read , enter_txt_read - enter_devfs_read , |
|---|
| 266 | enter_chdev_cmd_read , enter_chdev_cmd_read - enter_txt_read , |
|---|
| 267 | enter_chdev_server_read , enter_chdev_server_read - enter_chdev_cmd_read , |
|---|
| 268 | enter_tty_cmd_read , enter_tty_cmd_read - enter_chdev_server_read , |
|---|
| 269 | enter_tty_isr_read , enter_tty_isr_read - enter_tty_cmd_read , |
|---|
| 270 | exit_tty_isr_read , exit_tty_isr_read - enter_tty_isr_read , |
|---|
| 271 | exit_tty_cmd_read , exit_tty_cmd_read - exit_tty_isr_read , |
|---|
| 272 | exit_chdev_server_read , exit_chdev_server_read - exit_tty_cmd_read , |
|---|
| 273 | exit_chdev_cmd_read , exit_chdev_cmd_read - exit_chdev_server_read , |
|---|
| 274 | exit_txt_read , exit_txt_read - exit_chdev_cmd_read , |
|---|
| 275 | exit_devfs_read , exit_devfs_read - exit_txt_read , |
|---|
| 276 | exit_sys_read , exit_sys_read - exit_devfs_read ); |
|---|
| 277 | #endif |
|---|
| 278 | |
|---|
| 279 | return nbytes; |
|---|
| 280 | |
|---|
| 281 | } // end sys_read() |
|---|
