ubi.h

基于linux-2.6.28的mtd驱动

 * @peb_count: count of physical eraseblocks on the MTD device
 * @peb_size: physical eraseblock size
 * @bad_peb_count: count of bad physical eraseblocks
 * @good_peb_count: count of good physical eraseblocks
 * @min_io_size: minimal input/output unit size of the underlying MTD device
 * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
 * @ro_mode: if the UBI device is in read-only mode
 * @leb_size: logical eraseblock size
 * @leb_start: starting offset of logical eraseblocks within physical
 *             eraseblocks
 * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
 * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
 * @vid_hdr_offset: starting offset of the volume identifier header (might be
 *                  unaligned)
 * @vid_hdr_aloffset: starting offset of the VID header aligned to
 * @hdrs_min_io_size
 * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
 * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
 *               not
 * @mtd: MTD device descriptor
 *
 * @peb_buf1: a buffer of PEB size used for different purposes
 * @peb_buf2: another buffer of PEB size used for different purposes
 * @buf_mutex: proptects @peb_buf1 and @peb_buf2
 * @ckvol_mutex: serializes static volume checking when opening
 * @mult_mutex: serializes operations on multiple volumes, like re-nameing
 * @dbg_peb_buf: buffer of PEB size used for debugging
 * @dbg_buf_mutex: proptects @dbg_peb_buf
 */
struct ubi_device {
	struct cdev cdev;
	struct device dev;
	int ubi_num;
	char ubi_name[sizeof(UBI_NAME_STR)+5];
	int vol_count;
	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
	spinlock_t volumes_lock;
	int ref_count;

	int rsvd_pebs;
	int avail_pebs;
	int beb_rsvd_pebs;
	int beb_rsvd_level;

	int autoresize_vol_id;
	int vtbl_slots;
	int vtbl_size;
	struct ubi_vtbl_record *vtbl;
	struct mutex volumes_mutex;

	int max_ec;
	/* Note, mean_ec is not updated run-time - should be fixed */
	int mean_ec;

	/* EBA sub-system's stuff */
	unsigned long long global_sqnum;
	spinlock_t ltree_lock;
	struct rb_root ltree;
	struct mutex alc_mutex;

	/* Wear-leveling sub-system's stuff */
	struct rb_root used;
	struct rb_root free;
	struct rb_root scrub;
	struct {
		struct rb_root pnum;
		struct rb_root aec;
	} prot;
	spinlock_t wl_lock;
	struct mutex move_mutex;
	struct rw_semaphore work_sem;
	int wl_scheduled;
	struct ubi_wl_entry **lookuptbl;
	unsigned long long abs_ec;
	struct ubi_wl_entry *move_from;
	struct ubi_wl_entry *move_to;
	int move_to_put;
	struct list_head works;
	int works_count;
	struct task_struct *bgt_thread;
	int thread_enabled;
	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];

	/* I/O sub-system's stuff */
	long long flash_size;
	int peb_count;
	int peb_size;
	int bad_peb_count;
	int good_peb_count;
	int min_io_size;
	int hdrs_min_io_size;
	int ro_mode;
	int leb_size;
	int leb_start;
	int ec_hdr_alsize;
	int vid_hdr_alsize;
	int vid_hdr_offset;
	int vid_hdr_aloffset;
	int vid_hdr_shift;
	int bad_allowed;
	struct mtd_info *mtd;

	void *peb_buf1;
	void *peb_buf2;
	struct mutex buf_mutex;
	struct mutex ckvol_mutex;
	struct mutex mult_mutex;
#ifdef CONFIG_MTD_UBI_DEBUG
	void *dbg_peb_buf;
	struct mutex dbg_buf_mutex;
#endif
};

extern struct kmem_cache *ubi_wl_entry_slab;
extern struct file_operations ubi_ctrl_cdev_operations;
extern struct file_operations ubi_cdev_operations;
extern struct file_operations ubi_vol_cdev_operations;
extern struct class *ubi_class;
extern struct mutex ubi_devices_mutex;

/* vtbl.c */
int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
			   struct ubi_vtbl_record *vtbl_rec);
int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
			    struct list_head *rename_list);
int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si);

/* vmt.c */
int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);

/* upd.c */
int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
		     long long bytes);
int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
			 const void __user *buf, int count);
int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
			 const struct ubi_leb_change_req *req);
int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
			     const void __user *buf, int count);

/* misc.c */
int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
		      int length);
int ubi_check_volume(struct ubi_device *ubi, int vol_id);
void ubi_calculate_reserved(struct ubi_device *ubi);

/* gluebi.c */
#ifdef CONFIG_MTD_UBI_GLUEBI
int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol);
int ubi_destroy_gluebi(struct ubi_volume *vol);
void ubi_gluebi_updated(struct ubi_volume *vol);
#else
#define ubi_create_gluebi(ubi, vol) 0
#define ubi_destroy_gluebi(vol) 0
#define ubi_gluebi_updated(vol)
#endif

/* eba.c */
int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
		      int lnum);
int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
		     void *buf, int offset, int len, int check);
int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
		      const void *buf, int offset, int len, int dtype);
int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
			 int lnum, const void *buf, int len, int dtype,
			 int used_ebs);
int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
			      int lnum, const void *buf, int len, int dtype);
int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
		     struct ubi_vid_hdr *vid_hdr);
int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);

/* wl.c */
int ubi_wl_get_peb(struct ubi_device *ubi, int dtype);
int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture);
int ubi_wl_flush(struct ubi_device *ubi);
int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
void ubi_wl_close(struct ubi_device *ubi);
int ubi_thread(void *u);

/* io.c */
int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
		int len);
int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
		 int len);
int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
		       struct ubi_ec_hdr *ec_hdr, int verbose);
int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
			struct ubi_ec_hdr *ec_hdr);
int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
			struct ubi_vid_hdr *vid_hdr, int verbose);
int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
			 struct ubi_vid_hdr *vid_hdr);

/* build.c */
int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset);
int ubi_detach_mtd_dev(int ubi_num, int anyway);
struct ubi_device *ubi_get_device(int ubi_num);
void ubi_put_device(struct ubi_device *ubi);
struct ubi_device *ubi_get_by_major(int major);
int ubi_major2num(int major);

/*
 * ubi_rb_for_each_entry - walk an RB-tree.
 * @rb: a pointer to type 'struct rb_node' to to use as a loop counter
 * @pos: a pointer to RB-tree entry type to use as a loop counter
 * @root: RB-tree's root
 * @member: the name of the 'struct rb_node' within the RB-tree entry
 */
#define ubi_rb_for_each_entry(rb, pos, root, member)                         \
	for (rb = rb_first(root),                                            \
	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
	     rb;                                                             \
	     rb = rb_next(rb), pos = container_of(rb, typeof(*pos), member))

/**
 * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
 * @ubi: UBI device description object
 * @gfp_flags: GFP flags to allocate with
 *
 * This function returns a pointer to the newly allocated and zero-filled
 * volume identifier header object in case of success and %NULL in case of
 * failure.
 */
static inline struct ubi_vid_hdr *
ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)
{
	void *vid_hdr;

	vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);
	if (!vid_hdr)
		return NULL;

	/*
	 * VID headers may be stored at un-aligned flash offsets, so we shift
	 * the pointer.
	 */
	return vid_hdr + ubi->vid_hdr_shift;
}

/**
 * ubi_free_vid_hdr - free a volume identifier header object.
 * @ubi: UBI device description object
 * @vid_hdr: the object to free
 */
static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
				    struct ubi_vid_hdr *vid_hdr)
{
	void *p = vid_hdr;

	if (!p)
		return;

	kfree(p - ubi->vid_hdr_shift);
}

/*
 * This function is equivalent to 'ubi_io_read()', but @offset is relative to
 * the beginning of the logical eraseblock, not to the beginning of the
 * physical eraseblock.
 */
static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
				   int pnum, int offset, int len)
{
	ubi_assert(offset >= 0);
	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
}

/*
 * This function is equivalent to 'ubi_io_write()', but @offset is relative to
 * the beginning of the logical eraseblock, not to the beginning of the
 * physical eraseblock.
 */
static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
				    int pnum, int offset, int len)
{
	ubi_assert(offset >= 0);
	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
}

/**
 * ubi_ro_mode - switch to read-only mode.
 * @ubi: UBI device description object
 */
static inline void ubi_ro_mode(struct ubi_device *ubi)
{
	if (!ubi->ro_mode) {
		ubi->ro_mode = 1;
		ubi_warn("switch to read-only mode");
	}
}

/**
 * vol_id2idx - get table index by volume ID.
 * @ubi: UBI device description object
 * @vol_id: volume ID
 */
static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
{
	if (vol_id >= UBI_INTERNAL_VOL_START)
		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
	else
		return vol_id;
}

/**
 * idx2vol_id - get volume ID by table index.
 * @ubi: UBI device description object
 * @idx: table index
 */
static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
{
	if (idx >= ubi->vtbl_slots)
		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
	else
		return idx;
}

#endif /* !__UBI_UBI_H__ */