/* * sys_read.c - read bytes from a file * * Author Alain Greiner (2016,2017) * * Copyright (c) UPMC Sorbonne Universites * * This file is part of ALMOS-MKH. * * ALMOS-MKH is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2.0 of the License. * * ALMOS-MKH is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with ALMOS-MKH; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include #include #include #include #include #include #include #include #include #include // TODO: concurrent user page(s) munmap need to be handled [AG] // TODO : remove these debug variables extern uint32_t enter_sys_read; extern uint32_t enter_devfs_move; extern uint32_t enter_txt_read; extern uint32_t enter_chdev_cmd; extern uint32_t enter_chdev_server; extern uint32_t enter_tty_cmd; extern uint32_t enter_tty_isr; extern uint32_t exit_tty_isr; extern uint32_t exit_tty_cmd; extern uint32_t exit_chdev_server; extern uint32_t exit_chdev_cmd; extern uint32_t exit_txt_read; extern uint32_t exit_devfs_move; extern uint32_t exit_sys_read; ///////////////////////////////// int sys_read( uint32_t file_id, void * vaddr, uint32_t count ) { error_t error; paddr_t paddr; // required for user space checking xptr_t file_xp; // remote file extended pointer uint32_t nbytes; // number of bytes actually read reg_t save_sr; // required to enable IRQs during syscall #if CONFIG_SYSCALL_DEBUG uint32_t tm_start; uint32_t tm_end; tm_start = hal_get_cycles(); #endif #if CONFIG_READ_DEBUG enter_sys_read = tm_start; #endif thread_t * this = CURRENT_THREAD; process_t * process = this->process; // check file_id argument if( file_id >= CONFIG_PROCESS_FILE_MAX_NR ) { printk("\n[ERROR] in %s : illegal file descriptor index = %d\n", __FUNCTION__ , file_id ); this->errno = EBADFD; return -1; } // check user buffer in user space error = vmm_v2p_translate( false , vaddr , &paddr ); if ( error ) { printk("\n[ERROR] in %s : user buffer unmapped = %x\n", __FUNCTION__ , (intptr_t)vaddr ); this->errno = EINVAL; return -1; } // enable IRQs hal_enable_irq( &save_sr ); // get extended pointer on remote file descriptor file_xp = process_fd_get_xptr( process , file_id ); if( file_xp == XPTR_NULL ) { printk("\n[ERROR] in %s : undefined file descriptor index = %d in process %x\n", __FUNCTION__ , file_id , process->pid ); this->errno = EBADFD; return -1; } // get file descriptor cluster and local pointer vfs_file_t * file_ptr = (vfs_file_t *)GET_PTR( file_xp ); cxy_t file_cxy = GET_CXY( file_xp ); // check file readable uint32_t attr = hal_remote_lw( XPTR( file_cxy , &file_ptr->attr ) ); if( (attr & FD_ATTR_READ_ENABLE) == 0 ) { printk("\n[ERROR] in %s : file %d not readable in process %x\n", __FUNCTION__ , file_id , process->pid ); this->errno = EBADFD; return -1; } // get file type vfs_inode_type_t type = hal_remote_lw( XPTR( file_cxy , &file_ptr->type ) ); // action depend on file type if( type == INODE_TYPE_FILE ) // transfer count bytes from file mapper { nbytes = vfs_user_move( true, // from mapper to buffer file_xp, vaddr, count ); } else if( type == INODE_TYPE_DEV ) // transfer count bytes from device { nbytes = devfs_user_move( true, // from device to buffer file_xp, vaddr, count ); } else { nbytes = 0; panic("file type %d non supported yet", type ); } if( nbytes != count ) { printk("\n[ERROR] in %s cannot read data from file %d in process %x\n", __FUNCTION__ , file_id , process->pid ); this->errno = error; return -1; } // restore IRQs hal_restore_irq( save_sr ); hal_fence(); #if CONFIG_SYSCALL_DEBUG tm_end = hal_get_cycles(); syscall_dmsg("\n[DBG] %s exit : core[%x,%d] / thread %x in process %x / cycle %d\n" "nbytes = %d / first byte = %c / file_id = %d / cost = %d\n", __FUNCTION__ , local_cxy , this->core->lid , this->trdid , this->process->pid , tm_start , nbytes , *((char *)(intptr_t)paddr) , file_id , tm_end - tm_start ); #endif #if CONFIG_READ_DEBUG exit_sys_read = tm_end; printk("\n@@@@@@@@@@@@ timing to read character %c\n" " - enter_sys_read = %d / delta %d\n" " - enter_devfs_move = %d / delta %d\n" " - enter_txt_read = %d / delta %d\n" " - enter_chdev_cmd = %d / delta %d\n" " - enter_chdev_server = %d / delta %d\n" " - enter_tty_cmd = %d / delta %d\n" " - enter_tty_isr = %d / delta %d\n" " - exit_tty_isr = %d / delta %d\n" " - exit_tty_cmd = %d / delta %d\n" " - exit_chdev_server = %d / delta %d\n" " - exit_chdev_cmd = %d / delta %d\n" " - exit_txt_read = %d / delta %d\n" " - exit_devfs_move = %d / delta %d\n" " - exit_sys_read = %d / delta %d\n", *((char *)(intptr_t)paddr) , enter_sys_read , 0 , enter_devfs_move , enter_devfs_move - enter_sys_read , enter_txt_read , enter_txt_read - enter_devfs_move , enter_chdev_cmd , enter_chdev_cmd - enter_txt_read , enter_chdev_server , enter_chdev_server - enter_chdev_cmd , enter_tty_cmd , enter_tty_cmd - enter_chdev_server , enter_tty_isr , enter_tty_isr - enter_tty_cmd , exit_tty_isr , exit_tty_isr - enter_tty_isr , exit_tty_cmd , exit_tty_cmd - exit_tty_isr , exit_chdev_server , exit_chdev_server - exit_tty_cmd , exit_chdev_cmd , exit_chdev_cmd - exit_chdev_server , exit_txt_read , exit_txt_read - exit_chdev_cmd , exit_devfs_move , exit_devfs_move - exit_txt_read , exit_sys_read , exit_sys_read - exit_devfs_move ); #endif return nbytes; } // end sys_read()