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/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** FileX Component */
/** */
/** Media */
/** */
/**************************************************************************/
/**************************************************************************/
#define FX_SOURCE_CODE
/* Include necessary system files. */
#include "fx_api.h"
#include "fx_system.h"
#include "fx_media.h"
#include "fx_file.h"
#include "fx_directory.h"
#include "fx_utility.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _fx_media_flush PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function examines the list of open files for this media and */
/* "flushes" each written open file to the underlying media. After */
/* the open files have been flushed, the internal logical sector is */
/* flushed. Finally, the attached driver is sent a flush command so */
/* that it can flush its sector cache (if any) to the media. */
/* */
/* INPUT */
/* */
/* media_ptr Media control block pointer */
/* */
/* OUTPUT */
/* */
/* return status */
/* */
/* CALLS */
/* */
/* _fx_directory_entry_write Write the directory entry */
/* _fx_utility_FAT_flush Flush cached FAT entries */
/* _fx_utility_FAT_map_flush Flush primary FAT changes to */
/* secondary FAT(s) */
/* _fx_utility_logical_sector_flush Flush logical sector cache */
/* _fx_utility_32_unsigned_read Read 32-bit unsigned */
/* _fx_utility_32_unsigned_write Write 32-bit unsigned */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 05-19-2020 William E. Lamie Initial Version 6.0 */
/* 09-30-2020 William E. Lamie Modified comment(s), and */
/* added conditional to */
/* disable cache, */
/* resulting in version 6.1 */
/* */
/**************************************************************************/
UINT _fx_media_flush(FX_MEDIA *media_ptr)
{
UINT status;
ULONG open_count;
FX_FILE *file_ptr;
FX_INT_SAVE_AREA
#ifndef FX_MEDIA_STATISTICS_DISABLE
/* Increment the number of times this service has been called. */
media_ptr -> fx_media_flushes++;
#endif
/* Check the media to make sure it is open. */
if (media_ptr -> fx_media_id != FX_MEDIA_ID)
{
/* Return the media not opened error. */
return(FX_MEDIA_NOT_OPEN);
}
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_MEDIA_FLUSH, media_ptr, 0, 0, 0, FX_TRACE_MEDIA_EVENTS, 0, 0)
/* Protect against other threads accessing the media. */
FX_PROTECT
/* Check for write protect at the media level (set by driver). */
if (media_ptr -> fx_media_driver_write_protect)
{
/* Release media protection. */
FX_UNPROTECT
/* Return write protect error. */
return(FX_WRITE_PROTECT);
}
/* Loop through the media's open files. */
open_count = media_ptr -> fx_media_opened_file_count;
file_ptr = media_ptr -> fx_media_opened_file_list;
while (open_count)
{
/* Look at each opened file to see if the same file is opened
for writing and has been written to. */
if ((file_ptr -> fx_file_open_mode == FX_OPEN_FOR_WRITE) &&
(file_ptr -> fx_file_modified))
{
/* Protect against update. */
FX_DISABLE_INTS
/* Set the new time and date. */
file_ptr -> fx_file_dir_entry.fx_dir_entry_time = _fx_system_time;
file_ptr -> fx_file_dir_entry.fx_dir_entry_date = _fx_system_date;
/* Restore interrupts. */
FX_RESTORE_INTS
/* Copy the new file size into the directory entry. */
file_ptr -> fx_file_dir_entry.fx_dir_entry_file_size =
file_ptr -> fx_file_current_file_size;
/* Write the directory entry to the media. */
#ifdef FX_ENABLE_EXFAT
if (media_ptr -> fx_media_FAT_type == FX_exFAT)
{
status = _fx_directory_exFAT_entry_write(
media_ptr, &(file_ptr -> fx_file_dir_entry), UPDATE_STREAM);
}
else
{
#endif /* FX_ENABLE_EXFAT */
status = _fx_directory_entry_write(media_ptr, &(file_ptr -> fx_file_dir_entry));
#ifdef FX_ENABLE_EXFAT
}
#endif /* FX_ENABLE_EXFAT */
/* Check for a good status. */
if (status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Error writing the directory. */
return(status);
}
/* Clear the file modified flag. */
file_ptr -> fx_file_modified = FX_FALSE;
}
/* Adjust the pointer and decrement the opened count. */
file_ptr = file_ptr -> fx_file_opened_next;
open_count--;
}
/* Flush the cached individual FAT entries */
_fx_utility_FAT_flush(media_ptr);
/* Flush changed sector(s) in the primary FAT to secondary FATs. */
_fx_utility_FAT_map_flush(media_ptr);
#ifdef FX_ENABLE_EXFAT
if ((media_ptr -> fx_media_FAT_type == FX_exFAT) &&
(FX_TRUE == media_ptr -> fx_media_exfat_bitmap_cache_dirty))
{
/* Flush bitmap. */
_fx_utility_exFAT_bitmap_flush(media_ptr);
}
#endif /* FX_ENABLE_EXFAT */
/* Flush the internal logical sector cache. */
status = _fx_utility_logical_sector_flush(media_ptr, ((ULONG64) 1), (ULONG64) (media_ptr -> fx_media_total_sectors), FX_FALSE);
/* Check for a good status. */
if (status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Error writing the directory. */
return(status);
}
/* Determine if the media needs to have the additional information sector updated. This will
only be the case for 32-bit FATs. The logic here only needs to be done if the last reported
available cluster count is different that the currently available clusters. */
if ((media_ptr -> fx_media_FAT32_additional_info_sector) &&
(media_ptr -> fx_media_FAT32_additional_info_last_available != media_ptr -> fx_media_available_clusters))
{
UCHAR *buffer_ptr;
ULONG signature;
#ifndef FX_DISABLE_CACHE
/* Setup a pointer to the first cached entry's buffer. */
buffer_ptr = (media_ptr -> fx_media_sector_cache_list_ptr) -> fx_cached_sector_memory_buffer;
/* Invalidate this cache entry. */
(media_ptr -> fx_media_sector_cache_list_ptr) -> fx_cached_sector = (~(ULONG64)0);
(media_ptr -> fx_media_sector_cache_list_ptr) -> fx_cached_sector_valid = FX_FALSE;
#else
buffer_ptr = media_ptr -> fx_media_memory_buffer;
#endif /* FX_DISABLE_CACHE */
/* Read the FAT32 additional information sector from the device. */
media_ptr -> fx_media_driver_request = FX_DRIVER_READ;
media_ptr -> fx_media_driver_status = FX_IO_ERROR;
media_ptr -> fx_media_driver_buffer = buffer_ptr;
media_ptr -> fx_media_driver_logical_sector = media_ptr -> fx_media_FAT32_additional_info_sector;
media_ptr -> fx_media_driver_sectors = 1;
media_ptr -> fx_media_driver_sector_type = FX_DIRECTORY_SECTOR;
#ifndef FX_MEDIA_STATISTICS_DISABLE
/* Increment the number of driver read sector(s) requests. */
media_ptr -> fx_media_driver_read_requests++;
#endif
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_INTERNAL_IO_DRIVER_READ, media_ptr, media_ptr -> fx_media_FAT32_additional_info_sector, 1, buffer_ptr, FX_TRACE_INTERNAL_EVENTS, 0, 0)
/* Invoke the driver to read the FAT32 additional information sector. */
(media_ptr -> fx_media_driver_entry) (media_ptr);
/* Determine if the FAT32 sector was read correctly. */
if (media_ptr -> fx_media_driver_status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return the error status. */
return(FX_IO_ERROR);
}
/* Setup a pointer into the FAT32 additional information sector. */
buffer_ptr = media_ptr -> fx_media_driver_buffer;
/* Pickup the first signature long word. */
signature = _fx_utility_32_unsigned_read(&buffer_ptr[0]);
/* Determine if the signature is correct. */
if (signature == 0x41615252)
{
/* Yes, the first signature is correct, now pickup the next signature. */
signature = _fx_utility_32_unsigned_read(&buffer_ptr[484]);
/* Determine if this signature is correct. */
if (signature == 0x61417272)
{
/* Yes, we have a good FAT32 additional information sector. */
/* Set the free cluster count to the available clusters in the media control block. */
_fx_utility_32_unsigned_write(&buffer_ptr[488], media_ptr -> fx_media_available_clusters);
/* Set the next free cluster number hint to starting search cluster in the media control block. */
_fx_utility_32_unsigned_write(&buffer_ptr[492], media_ptr -> fx_media_cluster_search_start);
/* Now write the sector back out to the media. */
media_ptr -> fx_media_driver_request = FX_DRIVER_WRITE;
media_ptr -> fx_media_driver_status = FX_IO_ERROR;
media_ptr -> fx_media_driver_buffer = buffer_ptr;
media_ptr -> fx_media_driver_logical_sector = media_ptr -> fx_media_FAT32_additional_info_sector;
media_ptr -> fx_media_driver_sectors = 1;
media_ptr -> fx_media_driver_sector_type = FX_DIRECTORY_SECTOR;
/* Set the system write flag since we are writing a directory sector. */
media_ptr -> fx_media_driver_system_write = FX_TRUE;
#ifndef FX_MEDIA_STATISTICS_DISABLE
/* Increment the number of driver write sector(s) requests. */
media_ptr -> fx_media_driver_write_requests++;
#endif
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_INTERNAL_IO_DRIVER_WRITE, media_ptr, media_ptr -> fx_media_FAT32_additional_info_sector, 1, buffer_ptr, FX_TRACE_INTERNAL_EVENTS, 0, 0)
/* Invoke the driver to write the FAT32 additional information sector. */
(media_ptr -> fx_media_driver_entry) (media_ptr);
/* Clear the system write flag. */
media_ptr -> fx_media_driver_system_write = FX_FALSE;
/* Determine if the FAT32 sector was written correctly. */
if (media_ptr -> fx_media_driver_status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return the sector IO error status. */
return(FX_IO_ERROR);
}
/* Successful update of the FAT32 additional information sector. Update the
last written available cluster count. */
media_ptr -> fx_media_FAT32_additional_info_last_available = media_ptr -> fx_media_available_clusters;
}
}
}
#ifndef FX_MEDIA_STATISTICS_DISABLE
/* Increment the number of driver flush requests. */
media_ptr -> fx_media_driver_flush_requests++;
#endif
/* Build the "flush" I/O driver request. */
media_ptr -> fx_media_driver_request = FX_DRIVER_FLUSH;
media_ptr -> fx_media_driver_status = FX_IO_ERROR;
/* If trace is enabled, insert this event into the trace buffer. */
FX_TRACE_IN_LINE_INSERT(FX_TRACE_INTERNAL_IO_DRIVER_FLUSH, media_ptr, 0, 0, 0, FX_TRACE_INTERNAL_EVENTS, 0, 0)
/* Call the specified I/O driver with the flush request. */
(media_ptr -> fx_media_driver_entry) (media_ptr);
/* Determine if the I/O driver flushed successfully. */
if (media_ptr -> fx_media_driver_status != FX_SUCCESS)
{
/* Release media protection. */
FX_UNPROTECT
/* Return the driver error status. */
return(FX_IO_ERROR);
}
/* Release media protection. */
FX_UNPROTECT
/* If we get here, return successful status to the caller. */
return(FX_SUCCESS);
}