linux/fs/orangefs/devorangefs-req.c

// SPDX-License-Identifier: GPL-2.0
/*
 * (C) 2001 Clemson University and The University of Chicago
 *
 * Changes by Acxiom Corporation to add protocol version to kernel
 * communication, Copyright Acxiom Corporation, 2005.
 *
 * See COPYING in top-level directory.
 */

#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-dev-proto.h"
#include "orangefs-bufmap.h"
#include "orangefs-debugfs.h"

#include <linux/debugfs.h>
#include <linux/slab.h>

/* this file implements the /dev/pvfs2-req device node */

uint32_t orangefs_userspace_version;

static int open_access_count;

static DEFINE_MUTEX(devreq_mutex);

#define DUMP_DEVICE_ERROR() …

static int hash_func(__u64 tag, int table_size)
{ … }

static void orangefs_devreq_add_op(struct orangefs_kernel_op_s *op)
{ … }

/*
 * find the op with this tag and remove it from the in progress
 * hash table.
 */
static struct orangefs_kernel_op_s *orangefs_devreq_remove_op(__u64 tag)
{ … }

/* Returns whether any FS are still pending remounted */
static int mark_all_pending_mounts(void)
{ … }

/*
 * Determine if a given file system needs to be remounted or not
 *  Returns -1 on error
 *           0 if already mounted
 *           1 if needs remount
 */
static int fs_mount_pending(__s32 fsid)
{ … }

static int orangefs_devreq_open(struct inode *inode, struct file *file)
{ … }

/* Function for read() callers into the device */
static ssize_t orangefs_devreq_read(struct file *file,
				 char __user *buf,
				 size_t count, loff_t *offset)
{ … }

/*
 * Function for writev() callers into the device.
 *
 * Userspace should have written:
 *  - __u32 version
 *  - __u32 magic
 *  - __u64 tag
 *  - struct orangefs_downcall_s
 *  - trailer buffer (in the case of READDIR operations)
 */
static ssize_t orangefs_devreq_write_iter(struct kiocb *iocb,
				      struct iov_iter *iter)
{ … }

/*
 * NOTE: gets called when the last reference to this device is dropped.
 * Using the open_access_count variable, we enforce a reference count
 * on this file so that it can be opened by only one process at a time.
 * the devreq_mutex is used to make sure all i/o has completed
 * before we call orangefs_bufmap_finalize, and similar such tricky
 * situations
 */
static int orangefs_devreq_release(struct inode *inode, struct file *file)
{ … }

int is_daemon_in_service(void)
{ … }

bool __is_daemon_in_service(void)
{ … }

static inline long check_ioctl_command(unsigned int command)
{ … }

static long dispatch_ioctl_command(unsigned int command, unsigned long arg)
{ … }

static long orangefs_devreq_ioctl(struct file *file,
			       unsigned int command, unsigned long arg)
{ … }

#ifdef CONFIG_COMPAT		/* CONFIG_COMPAT is in .config */

/*  Compat structure for the ORANGEFS_DEV_MAP ioctl */
struct ORANGEFS_dev_map_desc32 { … };

/*
 * 32 bit user-space apps' ioctl handlers when kernel modules
 * is compiled as a 64 bit one
 */
static long orangefs_devreq_compat_ioctl(struct file *filp, unsigned int cmd,
				      unsigned long args)
{ … }

#endif /* CONFIG_COMPAT is in .config */

static __poll_t orangefs_devreq_poll(struct file *file,
				      struct poll_table_struct *poll_table)
{ … }

/* the assigned character device major number */
static int orangefs_dev_major;

static const struct file_operations orangefs_devreq_file_operations = …;

/*
 * Initialize orangefs device specific state:
 * Must be called at module load time only
 */
int orangefs_dev_init(void)
{ … }

void orangefs_dev_cleanup(void)
{ … }