incubator-nuttx/include/nuttx/fs/automount.h

200 lines
6.9 KiB
C

/****************************************************************************
* include/nuttx/fs/automount.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_FS_AUTOMOUNT_H
#define __INCLUDE_NUTTX_FS_AUTOMOUNT_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <stdint.h>
#include <stdbool.h>
#include <signal.h>
#include <nuttx/irq.h>
#ifdef CONFIG_FS_AUTOMOUNTER
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************
* Automounter configuration
* CONFIG_FS_AUTOMOUNTER - Enables automount support
*
* Prerequisites:
* CONFIG_SCHED_WORKQUEUE - Work queue support is required
* And others that would only matter if you are working in a very minimal
* configuration.
*/
/* Helper macros ************************************************************/
#define AUTOMOUNT_ATTACH(s,isr,arg) ((s)->attach(s,isr,arg))
#define AUTOMOUNT_DETACH(s) ((s)->attach(s,NULL,NULL))
#define AUTOMOUNT_ENABLE(s) ((s)->enable(s,true))
#define AUTOMOUNT_DISABLE(s) ((s)->enable(s,false))
#define AUTOMOUNT_INSERTED(s) ((s)->inserted(s))
/****************************************************************************
* Public Types
****************************************************************************/
/* This is the type of the automount media change handler. The lower level
* code will intercept the interrupt and provide the upper level with the
* private data that was provided when the interrupt was attached and will
* also provide an indication if the media was inserted or removed.
*/
struct automount_lower_s; /* Forward reference. Defined below */
typedef CODE int
(*automount_handler_t)(FAR const struct automount_lower_s *lower,
FAR void *arg, bool inserted);
#ifdef CONFIG_FS_AUTOMOUNTER_DRIVER
/* A reference to this structure is provided with the FIOC_NOTIFY IOCTL
* command and describes the conditions under which the client would like
* to receive notification.
*/
struct automount_notify_s
{
bool an_mount; /* FS mount to be notified */
bool an_umount; /* FS umount to be notified */
struct sigevent an_event; /* Describe the way a task is to be notified */
};
#endif /* CONFIG_FS_AUTOMOUNTER_DRIVER */
/* A reference to a structure of this type must be passed to the FS
* automounter. This structure provides information about the volume to be
* mounted and provides board-specific hooks.
*
* Memory for this structure is provided by the caller. It is not copied
* by the automounter and is presumed to persist while the automounter
* is active.
*/
struct automount_lower_s
{
/* Volume characterization */
FAR const char *fstype; /* Type of file system */
FAR const char *blockdev; /* Path to the block device */
FAR const char *mountpoint; /* Location to mount the volume */
/* Debounce delay in system clock ticks. Automount operation will not
* be performed until the insertion/removal state has been unchanges
* for this duration.
*/
uint32_t ddelay;
/* Unmount delay time in system clock ticks. If a volume has open
* references at the time that the media is removed, then we will be
* unable to unmount it. In that case, hopefully, the clients of the
* mount will eventually fail with file access errors and eventually close
* their references. So, at some time later, it should be possible to
* unmount the volume. This delay specifies the time between umount
* retries.
*/
uint32_t udelay;
/* Interrupt related operations all hidden behind callbacks to isolate the
* automounter from differences in interrupt handling by varying boards
* and MCUs. Board interrupts should be configured both insertion and
* removal of the media can be detected.
*
* attach - Attach or detach the media change interrupt handler to the
* board level interrupt
* enable - Enable or disable the media change interrupt
*/
CODE int (*attach)(FAR const struct automount_lower_s *lower,
automount_handler_t isr, FAR void *arg);
CODE void (*enable)(FAR const struct automount_lower_s *lower,
bool enable);
CODE bool (*inserted)(FAR const struct automount_lower_s *lower);
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: automount_initialize
*
* Description:
* Configure the automounter.
*
* Input Parameters:
* lower - Persistent board configuration data
*
* Returned Value:
* A void* handle.
* The only use for this handle is with automount_uninitialize().
* NULL is returned on any failure.
*
****************************************************************************/
FAR void *automount_initialize(FAR const struct automount_lower_s *lower);
/****************************************************************************
* Name: automount_uninitialize
*
* Description:
* Stop the automounter and free resources that it used. NOTE that the
* mount is left in its last state mounted/unmounted state.
*
* Input Parameters:
* handle - The value previously returned by automount_initialize();
*
* Returned Value:
* None
*
****************************************************************************/
void automount_uninitialize(FAR void *handle);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_FS_AUTOMOUNTER */
#endif /* __INCLUDE_NUTTX_FS_AUTOMOUNT_H */