mirror of
https://github.com/rvtr/twl_wrapsdk.git
synced 2025-10-31 06:11:10 -04:00
4fe5688d29
git-svn-id: file:///Users/lillianskinner/Downloads/platinum/twl/twl_wrapsdk/trunk@96 4ee2a332-4b2b-5046-8439-1ba90f034370
191 lines
8.6 KiB
C
191 lines
8.6 KiB
C
/*
|
|
* EBS - RTFS (Real Time File Manager)
|
|
*
|
|
* Copyright EBS Inc. 1987-2003
|
|
* All rights reserved.
|
|
* This code may not be redistributed in source or linkable object form
|
|
* without the consent of its author.
|
|
*
|
|
* This file is automatically included in rtfs.h if INCLUDE_FAILSAFE_CODE is enabled
|
|
* this file is note intended for inclusion by user code.
|
|
*/
|
|
/* PRFS.H - ERTFS-PRO Directory FailSafe routines */
|
|
|
|
/*
|
|
CFG_VALIDATE_JOURNAL - Set this to one to force a a low level read of the
|
|
whole journal file before it is accessed. If any of the reads call Failsafe
|
|
tries to recover by re-writing the whole file with zeros, for some media
|
|
types this will correct a read error. When the overwrite is completed
|
|
the file is read again, if that succeeds we continue, otherwise the journal
|
|
file open fails. A disk mount that encounters this error will fail and
|
|
errno will be set to PEIOERRORREADJOURNAL */
|
|
|
|
#define CFG_VALIDATE_JOURNAL 0
|
|
|
|
/*
|
|
CFG_VALIDATE_BUFFER_SIZE - This is the size, in blocks of the special
|
|
buffer dedicated to performing the tasks described in CFG_VALIDATE_JOURNAL.
|
|
The largest usable value for CFG_VALIDATE_BUFFER_SIZE is 128. Larger
|
|
values will not be utilized but memory will be wasted.
|
|
The whole journal file is scanned during startup in disk reads of up to
|
|
CFG_VALIDATE_BUFFER_SIZE blocks. Larger values will require fewer reads
|
|
and improve perfromance over smaller values.
|
|
The buffer is declared as:
|
|
static byte validate_buffer[CFG_VALIDATE_BUFFER_SIZE*512];
|
|
in prfsnvio.c.
|
|
If CFG_VALIDATE_JOURNAL is zero the value of CFG_VALIDATE_BUFFER_SIZE
|
|
is irrelevant because the buffer is not declared.
|
|
*/
|
|
|
|
#define CFG_VALIDATE_BUFFER_SIZE 64
|
|
|
|
/*
|
|
CFG_NUM_JOURNAL_BLOCKS - This is the default number of 512 byte blocks
|
|
to assign to the failsafe for journalling directory blocks. If
|
|
the user does not provide a non-zero value in the journal_size argument
|
|
to pro_failsafe_init() then the journal file will sized to be large
|
|
enough to hold the whole file allocation table plus CFG_NUM_JOURNAL_BLOCKS.
|
|
The default value is 128. This represents a very small percentage of all
|
|
but the smallest disks but it should be adequate for almost any imaginable
|
|
usage. It may be reduced to as little as 1 and FailSafe will still work
|
|
fine under most conditions.
|
|
*/
|
|
|
|
#define CFG_NUM_JOURNAL_BLOCKS 128
|
|
|
|
/*
|
|
CFG_NUM_INDEX_BUFFERS - This compile time constant determines number of
|
|
512 byte buffers to reserve for buffering FailSafe index pages. It
|
|
effects the size of the failsafe context structure. It must be at
|
|
least one and unless ram resources are very precious it should be
|
|
set to at least two if possible. The default value is 4 which should
|
|
be large enough for almost any application.
|
|
*/
|
|
|
|
#define CFG_NUM_INDEX_BUFFERS 4
|
|
|
|
/* Fail configuration and context structure */
|
|
typedef struct failsafecontext {
|
|
/* Configuration values to be set before calling pro_failsafe_init
|
|
and not modified thereafter */
|
|
#define FS_MODE_AUTORESTORE 0x01
|
|
#define FS_MODE_AUTORECOVER 0x02
|
|
#define FS_MODE_AUTOCOMMIT 0x04
|
|
/* Internal flags set by failsafe. Not user assignable */
|
|
#define FS_MODE_JOURNALING 0x08
|
|
int configuration_flags;
|
|
/* configuration_flags values
|
|
FS_MODE_AUTORESTORE- If removable media is reinserted and the
|
|
journal file indicates that restore is needed, automatically restore
|
|
and continue. If this flag is not set when this condition occurs
|
|
the mount of the volume fails and the errno is set to PEFSRESTORENEEDED,
|
|
the application must then handle this errno setting and call the
|
|
pro_failsafe_restore routine
|
|
FS_MODE_AUTORECOVER- If autorestore is required but the restore process
|
|
failed due to a bad journal file or IO error abort the restore but don't
|
|
report an error. Try to reinitialize the journal file and continue.
|
|
If a restore error did occur and FS_MODE_AUTORECOVER is not set the
|
|
mount will fail and errno will be set to PEFSRESTOREERROR
|
|
FS_MODE_AUTOCOMMIT- If AUTOCOMMIT is enabled the FailSafe commit operation
|
|
will be performed automatically be ERTFS at the completion of each API
|
|
call. With AUTOCOMMIT enabled the FailSafe operation is transparent to the
|
|
user and it is not necessary to call pro_failsafe_commit().
|
|
*/
|
|
dword user_journal_size; /* In blocks */
|
|
|
|
/* Internal elements, not intended to be accessed from user code */
|
|
DDRIVE *pdrive;
|
|
dword journal_file_size; /* In blocks */
|
|
dword num_index_blocks; /* Blocks reserved remap index */
|
|
dword num_remap_blocks; /* Blocks reserved for block remaps */
|
|
dword total_blocks_mapped; /* number of valid index entries */
|
|
dword journal_checksum; /* Checksum of all index entries */
|
|
dword known_free_clusters; /* number of valid index entries */
|
|
dword nv_buffer_handle;
|
|
int blockmap_size;
|
|
struct fsblockmap *blockmap_freelist;
|
|
struct fsblockmap *sorted_blockmap;
|
|
#define FAILSAFE_HASHTABLE_SIZE 16
|
|
#define FAILSAFE_HASHMASK 0xf
|
|
struct fsblockmap *blockmap_hash_tbl[FAILSAFE_HASHTABLE_SIZE];
|
|
int next_index_buffer;
|
|
int index_offset[CFG_NUM_INDEX_BUFFERS];
|
|
BOOLEAN index_dirty[CFG_NUM_INDEX_BUFFERS];
|
|
dword index_buffer[CFG_NUM_INDEX_BUFFERS][128];
|
|
byte scratch_block[512];
|
|
/* Internal variable used to differentiate between IO
|
|
errors and other errors during journal file re-opens */
|
|
int open_status;
|
|
} FAILSAFECONTEXT;
|
|
|
|
typedef struct fsblockmap {
|
|
struct fsblockmap *pnext;
|
|
struct fsblockmap *pnext_by_block;
|
|
dword blockno;
|
|
dword replacement_block;
|
|
} FSBLOCKMAP;
|
|
|
|
/* Return codes for pro_failsafe_restore() */
|
|
#define FS_STATUS_OK 0
|
|
#define FS_STATUS_NO_JOURNAL 1
|
|
#define FS_STATUS_BAD_JOURNAL 2
|
|
#define FS_STATUS_IO_ERROR 3
|
|
#define FS_STATUS_BAD_CHECKSUM 4
|
|
#define FS_STATUS_RESTORED 5
|
|
#define FS_STATUS_MUST_RESTORE 6
|
|
#define FS_STATUS_OUT_OF_DATE 7
|
|
#define FS_STATUS_NO_INIT 8
|
|
|
|
/* Failsafe api prototypes see prfsapi.c */
|
|
BOOLEAN pro_failsafe_init(byte *drivename, FAILSAFECONTEXT *pfscntxt);
|
|
BOOLEAN pro_failsafe_commit(byte *path);
|
|
int pro_failsafe_restore(byte *drive_name, FAILSAFECONTEXT *fscntxt, BOOLEAN dorestore,BOOLEAN doclear);
|
|
BOOLEAN pro_failsafe_auto_init(DDRIVE *pdrive);
|
|
BOOLEAN pro_failsafe_shutdown(byte *drive_name, BOOLEAN abort);
|
|
|
|
|
|
/* Routines called internally by ertfs. see prfscore.c */
|
|
BOOLEAN pro_failsafe_dskopen(DDRIVE *pdrive);
|
|
BOOLEAN pro_failsafe_autorestore(DDRIVE *pdrive);
|
|
void fs_rewind_failsafe(FAILSAFECONTEXT *pfscntxt);
|
|
|
|
/* The rest of this header file contains information that is internal to
|
|
failsafe */
|
|
#define FS_JOURNAL_SIGNATURE_1 0x4641494C /* 'F''A''I''L' */
|
|
#define FS_JOURNAL_SIGNATURE_2 0x53414645 /* 'S''A''F''E' */
|
|
/* April-2004 version 2. - substantial rework */
|
|
#define FS_JOURNAL_VERSION 0x00000002
|
|
#define FS_STATUS_PROCESSING 0x01010101
|
|
#define FS_STATUS_COMPLETE 0x11111111
|
|
|
|
/* Internal field offsets in failsafe header */
|
|
#define INDEX_OFFSET_SIGNATURE_1 0
|
|
#define INDEX_OFFSET_SIGNATURE_2 1
|
|
#define INDEX_OFFSET_VERSION 2
|
|
#define INDEX_OFFSET_INDEX_STATUS 3
|
|
#define INDEX_OFFSET_TOTAL_BLOCKS_MAPPED 4
|
|
#define INDEX_OFFSET_INDEX_CHECKSUM 5
|
|
#define INDEX_OFFSET_FREE_CLUSTERS 6
|
|
#define INDEX_OFFSET_NUMB_INDEX_BLOCKS 7
|
|
#define INDEX_OFFSET_NUMB_REMAP_BLOCKS 8
|
|
#define JOURNAL_HEADER_SIZE 9 /* First 9 dwords are status */
|
|
#define JOURNAL_ENTRIES_P_BLOCK 128
|
|
#define JOURNAL_ENTRIES_ZERO (JOURNAL_ENTRIES_P_BLOCK-JOURNAL_HEADER_SIZE)
|
|
|
|
/* Prototypes of internal function implemented in prfscore.c */
|
|
BOOLEAN pro_failsafe_init_internal(DDRIVE *pdrive, FAILSAFECONTEXT *pfscntxt);
|
|
int pro_failsafe_commit_internal(FAILSAFECONTEXT *pfscntxt);
|
|
int failsafe_restore_internal(FAILSAFECONTEXT *pfscntxt, BOOLEAN dorestore, BOOLEAN doclear);
|
|
BOOLEAN pro_failsafe_dskopen(DDRIVE *pdrive);
|
|
BOOLEAN pro_failsafe_autorestore(DDRIVE *pdrive);
|
|
BOOLEAN pro_failsafe_autocommit(DDRIVE *pdrive);
|
|
BOOLEAN pro_failsafe_journal_full(DDRIVE *pdrive);
|
|
|
|
/* Prototypes of internal function implemented in prfsnvio.c */
|
|
BOOLEAN failsafe_reopen_nv_buffer(FAILSAFECONTEXT *pfscntxt);
|
|
BOOLEAN failsafe_create_nv_buffer(FAILSAFECONTEXT *pfscntxt);
|
|
BOOLEAN failsafe_write_nv_buffer(FAILSAFECONTEXT *pfscntxt, dword block_no, byte *pblock);
|
|
BOOLEAN failsafe_read_nv_buffer(FAILSAFECONTEXT *pfscntxt, dword block_no, byte *pblock);
|
|
|
|
|