kernel_liteos_a/fs/vfs/operation/vfs_procfd.c

477 lines
12 KiB
C

/*
* Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
* Copyright (c) 2020-2021 Huawei Device Co., Ltd. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "fs/file.h"
#include "los_process_pri.h"
#include "fs/fd_table.h"
#include "mqueue.h"
#ifdef LOSCFG_NET_LWIP_SACK
#include "lwip/sockets.h"
#endif
void FileTableLock(struct fd_table_s *fdt)
{
/* Take the semaphore (perhaps waiting) */
while (sem_wait(&fdt->ft_sem) != 0) {
/*
* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
LOS_ASSERT(errno == EINTR);
}
}
void FileTableUnLock(struct fd_table_s *fdt)
{
int ret = sem_post(&fdt->ft_sem);
if (ret == -1) {
PRINTK("sem_post error, errno %d \n", get_errno());
}
}
static int AssignProcessFd(const struct fd_table_s *fdt, int minFd)
{
if (minFd >= fdt->max_fds) {
set_errno(EINVAL);
return VFS_ERROR;
}
/* search unused fd from table */
for (int i = minFd; i < fdt->max_fds; i++) {
if (!FD_ISSET(i, fdt->proc_fds)) {
return i;
}
}
set_errno(EMFILE);
return VFS_ERROR;
}
struct fd_table_s *GetFdTable(void)
{
struct fd_table_s *fdt = NULL;
struct files_struct *procFiles = OsCurrProcessGet()->files;
if (procFiles == NULL) {
return NULL;
}
fdt = procFiles->fdt;
if ((fdt == NULL) || (fdt->ft_fds == NULL)) {
return NULL;
}
return fdt;
}
static bool IsValidProcessFd(struct fd_table_s *fdt, int procFd)
{
if (fdt == NULL) {
return false;
}
if ((procFd < 0) || (procFd >= fdt->max_fds)) {
return false;
}
return true;
}
void AssociateSystemFd(int procFd, int sysFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return;
}
if (sysFd < 0) {
return;
}
FileTableLock(fdt);
fdt->ft_fds[procFd].sysFd = sysFd;
FileTableUnLock(fdt);
}
int CheckProcessFd(int procFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return VFS_ERROR;
}
return OK;
}
int GetAssociatedSystemFd(int procFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return VFS_ERROR;
}
FileTableLock(fdt);
if (fdt->ft_fds[procFd].sysFd < 0) {
FileTableUnLock(fdt);
return VFS_ERROR;
}
int sysFd = fdt->ft_fds[procFd].sysFd;
FileTableUnLock(fdt);
return sysFd;
}
/* Occupy the procFd, there are three circumstances:
* 1.procFd is already associated, we need disassociate procFd with relevant sysfd.
* 2.procFd is not allocated, we occupy it immediately.
* 3.procFd is in open(), close(), dup() process, we return EBUSY immediately.
*/
int AllocSpecifiedProcessFd(int procFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return -EBADF;
}
FileTableLock(fdt);
if (fdt->ft_fds[procFd].sysFd >= 0) {
/* Disassociate procFd */
fdt->ft_fds[procFd].sysFd = -1;
FileTableUnLock(fdt);
return OK;
}
if (FD_ISSET(procFd, fdt->proc_fds)) {
/* procFd in race condition */
FileTableUnLock(fdt);
return -EBUSY;
} else {
/* Unused procFd */
FD_SET(procFd, fdt->proc_fds);
}
FileTableUnLock(fdt);
return OK;
}
void FreeProcessFd(int procFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return;
}
FileTableLock(fdt);
FD_CLR(procFd, fdt->proc_fds);
FD_CLR(procFd, fdt->cloexec_fds);
fdt->ft_fds[procFd].sysFd = -1;
FileTableUnLock(fdt);
}
int DisassociateProcessFd(int procFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return VFS_ERROR;
}
FileTableLock(fdt);
if (fdt->ft_fds[procFd].sysFd < 0) {
FileTableUnLock(fdt);
return VFS_ERROR;
}
int sysFd = fdt->ft_fds[procFd].sysFd;
if (procFd >= MIN_START_FD) {
fdt->ft_fds[procFd].sysFd = -1;
}
FileTableUnLock(fdt);
return sysFd;
}
int AllocProcessFd(void)
{
return AllocLowestProcessFd(MIN_START_FD);
}
int AllocLowestProcessFd(int minFd)
{
struct fd_table_s *fdt = GetFdTable();
if (fdt == NULL) {
return VFS_ERROR;
}
/* minFd should be a positive number,and 0,1,2 had be distributed to stdin,stdout,stderr */
if (minFd < MIN_START_FD) {
minFd = MIN_START_FD;
}
FileTableLock(fdt);
int procFd = AssignProcessFd(fdt, minFd);
if (procFd == VFS_ERROR) {
FileTableUnLock(fdt);
return VFS_ERROR;
}
/* occupy the fd set */
FD_SET(procFd, fdt->proc_fds);
FileTableUnLock(fdt);
return procFd;
}
int AllocAndAssocProcessFd(int sysFd, int minFd)
{
struct fd_table_s *fdt = GetFdTable();
if (fdt == NULL) {
return VFS_ERROR;
}
/* minFd should be a positive number,and 0,1,2 had be distributed to stdin,stdout,stderr */
if (minFd < MIN_START_FD) {
minFd = MIN_START_FD;
}
FileTableLock(fdt);
int procFd = AssignProcessFd(fdt, minFd);
if (procFd == VFS_ERROR) {
FileTableUnLock(fdt);
return VFS_ERROR;
}
/* occupy the fd set */
FD_SET(procFd, fdt->proc_fds);
fdt->ft_fds[procFd].sysFd = sysFd;
FileTableUnLock(fdt);
return procFd;
}
int AllocAndAssocSystemFd(int procFd, int minFd)
{
struct fd_table_s *fdt = GetFdTable();
if (!IsValidProcessFd(fdt, procFd)) {
return VFS_ERROR;
}
int sysFd = alloc_fd(minFd);
if (sysFd < 0) {
return VFS_ERROR;
}
FileTableLock(fdt);
fdt->ft_fds[procFd].sysFd = sysFd;
FileTableUnLock(fdt);
return sysFd;
}
static void FdRefer(int sysFd)
{
if ((sysFd > STDERR_FILENO) && (sysFd < CONFIG_NFILE_DESCRIPTORS)) {
files_refer(sysFd);
}
#if defined(LOSCFG_NET_LWIP_SACK)
if ((sysFd >= CONFIG_NFILE_DESCRIPTORS) && (sysFd < (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS))) {
socks_refer(sysFd);
}
#endif
#if defined(LOSCFG_COMPAT_POSIX)
if ((sysFd >= MQUEUE_FD_OFFSET) && (sysFd < (MQUEUE_FD_OFFSET + CONFIG_NQUEUE_DESCRIPTORS))) {
MqueueRefer(sysFd);
}
#endif
}
static void FdClose(int sysFd, unsigned int targetPid)
{
UINT32 intSave;
if ((sysFd > STDERR_FILENO) && (sysFd < CONFIG_NFILE_DESCRIPTORS)) {
LosProcessCB *processCB = OS_PCB_FROM_PID(targetPid);
SCHEDULER_LOCK(intSave);
if (OsProcessIsInactive(processCB)) {
SCHEDULER_UNLOCK(intSave);
return;
}
SCHEDULER_UNLOCK(intSave);
files_close_internal(sysFd, processCB);
}
#if defined(LOSCFG_NET_LWIP_SACK)
if ((sysFd >= CONFIG_NFILE_DESCRIPTORS) && (sysFd < (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS))) {
socks_close(sysFd);
}
#endif
#if defined(LOSCFG_COMPAT_POSIX)
if ((sysFd >= MQUEUE_FD_OFFSET) && (sysFd < (MQUEUE_FD_OFFSET + CONFIG_NQUEUE_DESCRIPTORS))) {
mq_close((mqd_t)sysFd);
}
#endif
}
static struct fd_table_s *GetProcessFTable(unsigned int pid, sem_t *semId)
{
UINT32 intSave;
struct files_struct *procFiles = NULL;
LosProcessCB *processCB = OS_PCB_FROM_PID(pid);
SCHEDULER_LOCK(intSave);
if (OsProcessIsInactive(processCB)) {
SCHEDULER_UNLOCK(intSave);
return NULL;
}
procFiles = processCB->files;
if (procFiles == NULL || procFiles->fdt == NULL) {
SCHEDULER_UNLOCK(intSave);
return NULL;
}
*semId = procFiles->fdt->ft_sem;
SCHEDULER_UNLOCK(intSave);
return procFiles->fdt;
}
int CopyFdToProc(int fd, unsigned int targetPid)
{
#if !defined(LOSCFG_NET_LWIP_SACK) && !defined(LOSCFG_COMPAT_POSIX) && !defined(LOSCFG_FS_VFS)
return -ENOSYS;
#else
int sysFd;
struct fd_table_s *fdt = NULL;
int procFd;
sem_t semId;
if (OS_PID_CHECK_INVALID(targetPid)) {
return -EINVAL;
}
sysFd = GetAssociatedSystemFd(fd);
if (sysFd < 0) {
return -EBADF;
}
FdRefer(sysFd);
fdt = GetProcessFTable(targetPid, &semId);
if (fdt == NULL || fdt->ft_fds == NULL) {
FdClose(sysFd, targetPid);
return -EPERM;
}
/* Take the semaphore (perhaps waiting) */
if (sem_wait(&semId) != 0) {
/* Target process changed */
FdClose(sysFd, targetPid);
return -ESRCH;
}
procFd = AssignProcessFd(fdt, 3); // minfd is 3
if (procFd < 0) {
if (sem_post(&semId) == -1) {
PRINT_ERR("sem_post error, errno %d \n", get_errno());
}
FdClose(sysFd, targetPid);
return -EPERM;
}
/* occupy the fd set */
FD_SET(procFd, fdt->proc_fds);
fdt->ft_fds[procFd].sysFd = sysFd;
if (sem_post(&semId) == -1) {
PRINTK("sem_post error, errno %d \n", get_errno());
}
return procFd;
#endif
}
int CloseProcFd(int procFd, unsigned int targetPid)
{
#if !defined(LOSCFG_NET_LWIP_SACK) && !defined(LOSCFG_COMPAT_POSIX) && !defined(LOSCFG_FS_VFS)
return -ENOSYS;
#else
int sysFd;
struct fd_table_s *fdt = NULL;
sem_t semId;
if (OS_PID_CHECK_INVALID(targetPid)) {
return -EINVAL;
}
fdt = GetProcessFTable(targetPid, &semId);
if (fdt == NULL || fdt->ft_fds == NULL) {
return -EPERM;
}
/* Take the semaphore (perhaps waiting) */
if (sem_wait(&semId) != 0) {
/* Target process changed */
return -ESRCH;
}
if (!IsValidProcessFd(fdt, procFd)) {
if (sem_post(&semId) == -1) {
PRINTK("sem_post error, errno %d \n", get_errno());
}
return -EPERM;
}
sysFd = fdt->ft_fds[procFd].sysFd;
if (sysFd < 0) {
if (sem_post(&semId) == -1) {
PRINTK("sem_post error, errno %d \n", get_errno());
}
return -EPERM;
}
/* clean the fd set */
FD_CLR(procFd, fdt->proc_fds);
FD_CLR(procFd, fdt->cloexec_fds);
fdt->ft_fds[procFd].sysFd = -1;
if (sem_post(&semId) == -1) {
PRINTK("sem_post error, errno %d \n", get_errno());
}
FdClose(sysFd, targetPid);
return 0;
#endif
}