linux/fs/jffs2/jffs2_fs_sb.h

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/* $Id: jffs2_fs_sb.h,v 1.54 2005/09/21 13:37:34 dedekind Exp $ */
#ifndef _JFFS2_FS_SB
#define _JFFS2_FS_SB
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/completion.h>
#include <asm/semaphore.h>
#include <linux/timer.h>
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/rwsem.h>
#define JFFS2_SB_FLAG_RO 1
#define JFFS2_SB_FLAG_SCANNING 2 /* Flash scanning is in progress */
#define JFFS2_SB_FLAG_BUILDING 4 /* File system building is in progress */
struct jffs2_inodirty;
/* A struct for the overall file system control. Pointers to
jffs2_sb_info structs are named `c' in the source code.
Nee jffs_control
*/
struct jffs2_sb_info {
struct mtd_info *mtd;
uint32_t highest_ino;
uint32_t checked_ino;
unsigned int flags;
struct task_struct *gc_task; /* GC task struct */
struct completion gc_thread_start; /* GC thread start completion */
struct completion gc_thread_exit; /* GC thread exit completion port */
struct semaphore alloc_sem; /* Used to protect all the following
fields, and also to protect against
out-of-order writing of nodes. And GC. */
uint32_t cleanmarker_size; /* Size of an _inline_ CLEANMARKER
(i.e. zero for OOB CLEANMARKER */
uint32_t flash_size;
uint32_t used_size;
uint32_t dirty_size;
uint32_t wasted_size;
uint32_t free_size;
uint32_t erasing_size;
uint32_t bad_size;
uint32_t sector_size;
uint32_t unchecked_size;
uint32_t nr_free_blocks;
uint32_t nr_erasing_blocks;
/* Number of free blocks there must be before we... */
uint8_t resv_blocks_write; /* ... allow a normal filesystem write */
uint8_t resv_blocks_deletion; /* ... allow a normal filesystem deletion */
uint8_t resv_blocks_gctrigger; /* ... wake up the GC thread */
uint8_t resv_blocks_gcbad; /* ... pick a block from the bad_list to GC */
uint8_t resv_blocks_gcmerge; /* ... merge pages when garbage collecting */
uint32_t nospc_dirty_size;
uint32_t nr_blocks;
struct jffs2_eraseblock *blocks; /* The whole array of blocks. Used for getting blocks
* from the offset (blocks[ofs / sector_size]) */
struct jffs2_eraseblock *nextblock; /* The block we're currently filling */
struct jffs2_eraseblock *gcblock; /* The block we're currently garbage-collecting */
struct list_head clean_list; /* Blocks 100% full of clean data */
struct list_head very_dirty_list; /* Blocks with lots of dirty space */
struct list_head dirty_list; /* Blocks with some dirty space */
struct list_head erasable_list; /* Blocks which are completely dirty, and need erasing */
struct list_head erasable_pending_wbuf_list; /* Blocks which need erasing but only after the current wbuf is flushed */
struct list_head erasing_list; /* Blocks which are currently erasing */
struct list_head erase_pending_list; /* Blocks which need erasing now */
struct list_head erase_complete_list; /* Blocks which are erased and need the clean marker written to them */
struct list_head free_list; /* Blocks which are free and ready to be used */
struct list_head bad_list; /* Bad blocks. */
struct list_head bad_used_list; /* Bad blocks with valid data in. */
spinlock_t erase_completion_lock; /* Protect free_list and erasing_list
against erase completion handler */
wait_queue_head_t erase_wait; /* For waiting for erases to complete */
wait_queue_head_t inocache_wq;
struct jffs2_inode_cache **inocache_list;
spinlock_t inocache_lock;
/* Sem to allow jffs2_garbage_collect_deletion_dirent to
drop the erase_completion_lock while it's holding a pointer
to an obsoleted node. I don't like this. Alternatives welcomed. */
struct semaphore erase_free_sem;
uint32_t wbuf_pagesize; /* 0 for NOR and other flashes with no wbuf */
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
/* Write-behind buffer for NAND flash */
unsigned char *wbuf;
[MTD] Rework the out of band handling completely Hopefully the last iteration on this! The handling of out of band data on NAND was accompanied by tons of fruitless discussions and halfarsed patches to make it work for a particular problem. Sufficiently annoyed by I all those "I know it better" mails and the resonable amount of discarded "it solves my problem" patches, I finally decided to go for the big rework. After removing the _ecc variants of mtd read/write functions the solution to satisfy the various requirements was to refactor the read/write _oob functions in mtd. The major change is that read/write_oob now takes a pointer to an operation descriptor structure "struct mtd_oob_ops".instead of having a function with at least seven arguments. read/write_oob which should probably renamed to a more descriptive name, can do the following tasks: - read/write out of band data - read/write data content and out of band data - read/write raw data content and out of band data (ecc disabled) struct mtd_oob_ops has a mode field, which determines the oob handling mode. Aside of the MTD_OOB_RAW mode, which is intended to be especially for diagnostic purposes and some internal functions e.g. bad block table creation, the other two modes are for mtd clients: MTD_OOB_PLACE puts/gets the given oob data exactly to/from the place which is described by the ooboffs and ooblen fields of the mtd_oob_ops strcuture. It's up to the caller to make sure that the byte positions are not used by the ECC placement algorithms. MTD_OOB_AUTO puts/gets the given oob data automaticaly to/from the places in the out of band area which are described by the oobfree tuples in the ecclayout data structre which is associated to the devicee. The decision whether data plus oob or oob only handling is done depends on the setting of the datbuf member of the data structure. When datbuf == NULL then the internal read/write_oob functions are selected, otherwise the read/write data routines are invoked. Tested on a few platforms with all variants. Please be aware of possible regressions for your particular device / application scenario Disclaimer: Any whining will be ignored from those who just contributed "hot air blurb" and never sat down to tackle the underlying problem of the mess in the NAND driver grown over time and the big chunk of work to fix up the existing users. The problem was not the holiness of the existing MTD interfaces. The problems was the lack of time to go for the big overhaul. It's easy to add more mess to the existing one, but it takes alot of effort to go for a real solution. Improvements and bugfixes are welcome! Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2006-05-29 03:26:58 +02:00
unsigned char *oobbuf;
uint32_t wbuf_ofs;
uint32_t wbuf_len;
struct jffs2_inodirty *wbuf_inodes;
struct rw_semaphore wbuf_sem; /* Protects the write buffer */
/* Information about out-of-band area usage... */
struct nand_ecclayout *ecclayout;
uint32_t badblock_pos;
uint32_t fsdata_pos;
uint32_t fsdata_len;
#endif
struct jffs2_summary *summary; /* Summary information */
#ifdef CONFIG_JFFS2_FS_XATTR
#define XATTRINDEX_HASHSIZE (57)
uint32_t highest_xid;
uint32_t highest_xseqno;
struct list_head xattrindex[XATTRINDEX_HASHSIZE];
struct list_head xattr_unchecked;
struct list_head xattr_dead_list;
struct jffs2_xattr_ref *xref_dead_list;
struct jffs2_xattr_ref *xref_temp;
struct rw_semaphore xattr_sem;
uint32_t xdatum_mem_usage;
uint32_t xdatum_mem_threshold;
#endif
/* OS-private pointer for getting back to master superblock info */
void *os_priv;
};
#endif /* _JFFS2_FB_SB */