From 8693ae1bd880a758eb2efec4fccd32f89593855d Mon Sep 17 00:00:00 2001 From: Nebuleon Fumika Date: Sun, 3 Feb 2013 04:19:11 -0500 Subject: Add SDK modifications by BassAceGold as of 2011-04-14, as well as modified DMA functions as of 2013-01-29. --- sdk-modifications/libsrc/fs/fs_cache.h | 125 +++++++++++++++++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 sdk-modifications/libsrc/fs/fs_cache.h (limited to 'sdk-modifications/libsrc/fs/fs_cache.h') diff --git a/sdk-modifications/libsrc/fs/fs_cache.h b/sdk-modifications/libsrc/fs/fs_cache.h new file mode 100644 index 0000000..1abae66 --- /dev/null +++ b/sdk-modifications/libsrc/fs/fs_cache.h @@ -0,0 +1,125 @@ +/* + cache.h + The cache is not visible to the user. It should be flushed + when any file is closed or changes are made to the filesystem. + + This cache implements a least-used-page replacement policy. This will + distribute sectors evenly over the pages, so if less than the maximum + pages are used at once, they should all eventually remain in the cache. + This also has the benefit of throwing out old sectors, so as not to keep + too many stale pages around. + + Copyright (c) 2006 Michael "Chishm" Chisholm + + 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. The name of the author may not be used to endorse or promote products derived + from this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. + + 2006-07-11 - Chishm + * Original release +*/ + +#ifndef _CACHE_H +#define _CACHE_H + +#include "fs_common.h" +#include "disc_io/disc_io.h" + +#define CACHE_PAGE_SIZE BYTES_PER_READ + +typedef struct { + u32 sector; + u32 count; + bool dirty; +} CACHE_ENTRY; + +typedef struct { + const IO_INTERFACE* disc; + u32 numberOfPages; + CACHE_ENTRY* cacheEntries; + u8* pages; +} CACHE; + + +/* +Read data from a sector in the cache +If the sector is not in the cache, it will be swapped in +offset is the position to start reading from +size is the amount of data to read +Precondition: offset + size <= BYTES_PER_READ +*/ +bool _FAT_cache_readPartialSector (CACHE* cache, void* buffer, u32 sector, u32 offset, u32 size); + +/* +Write data to a sector in the cache +If the sector is not in the cache, it will be swapped in. +When the sector is swapped out, the data will be written to the disc +offset is the position to start reading from +size is the amount of data to read +Precondition: offset + size <= BYTES_PER_READ +*/ +bool _FAT_cache_writePartialSector (CACHE* cache, const void* buffer, u32 sector, u32 offset, u32 size); + +/* +some where call _FAT_cache_writePartialSector to cache sector m , but later, another +place(in fwrite function) directly write data to sector m, in this case, need to +cancel the dirty state of sector m +*/ +void _FAT_cache_writePartialSector_check (CACHE* cache, u32 sector, u32 num, const void* buffer); + +/* +Write data to a sector in the cache, zeroing the sector first +If the sector is not in the cache, it will be swapped in. +When the sector is swapped out, the data will be written to the disc +offset is the position to start reading from +size is the amount of data to read +Precondition: offset + size <= BYTES_PER_READ +*/ +bool _FAT_cache_eraseWritePartialSector (CACHE* cache, const void* buffer, u32 sector, u32 offset, u32 size); + +/* +Read a full sector from the cache +*/ +static inline bool _FAT_cache_readSector (CACHE* cache, void* buffer, u32 sector) { + return _FAT_cache_readPartialSector (cache, buffer, sector, 0, BYTES_PER_READ); +} + +/* +Write a full sector to the cache +*/ +static inline bool _FAT_cache_writeSector (CACHE* cache, const void* buffer, u32 sector) { + return _FAT_cache_writePartialSector (cache, buffer, sector, 0, BYTES_PER_READ); +} + +/* +Write any dirty sectors back to disc and clear out the contents of the cache +*/ +bool _FAT_cache_flush (CACHE* cache); + +/* +Clear out the contents of the cache without writing any dirty sectors first +*/ +void _FAT_cache_invalidate (CACHE* cache); + +CACHE* _FAT_cache_constructor (u32 numberOfPages, const IO_INTERFACE* discInterface); + +void _FAT_cache_destructor (CACHE* cache); + +#endif // _CACHE_H -- cgit v1.2.3