Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6

* 'linux-next' of git://git.infradead.org/ubifs-2.6: (25 commits)
  UBIFS: clean-up commentaries
  UBIFS: save 128KiB or more RAM
  UBIFS: allocate orphans scan buffer on demand
  UBIFS: allocate lpt dump buffer on demand
  UBIFS: allocate ltab checking buffer on demand
  UBIFS: allocate scanning buffer on demand
  UBIFS: allocate dump buffer on demand
  UBIFS: do not check data crc by default
  UBIFS: simplify UBIFS Kconfig menu
  UBIFS: print max. index node size
  UBIFS: handle allocation failures in UBIFS write path
  UBIFS: use max_write_size during recovery
  UBIFS: use max_write_size for write-buffers
  UBIFS: introduce write-buffer size field
  UBI: incorporate LEB offset information
  UBIFS: incorporate maximum write size
  UBI: provide LEB offset information
  UBI: incorporate maximum write size
  UBIFS: fix LEB number in printk
  UBIFS: restrict world-writable debugfs files
  ...
This commit is contained in:
Linus Torvalds
2011-03-18 10:50:27 -07:00
19 changed files with 490 additions and 176 deletions

View File

@@ -116,18 +116,40 @@ struct ubi_volume_info {
* struct ubi_device_info - UBI device description data structure.
* @ubi_num: ubi device number
* @leb_size: logical eraseblock size on this UBI device
* @leb_start: starting offset of logical eraseblocks within physical
* eraseblocks
* @min_io_size: minimal I/O unit size
* @max_write_size: maximum amount of bytes the underlying flash can write at a
* time (MTD write buffer size)
* @ro_mode: if this device is in read-only mode
* @cdev: UBI character device major and minor numbers
*
* Note, @leb_size is the logical eraseblock size offered by the UBI device.
* Volumes of this UBI device may have smaller logical eraseblock size if their
* alignment is not equivalent to %1.
*
* The @max_write_size field describes flash write maximum write unit. For
* example, NOR flash allows for changing individual bytes, so @min_io_size is
* %1. However, it does not mean than NOR flash has to write data byte-by-byte.
* Instead, CFI NOR flashes have a write-buffer of, e.g., 64 bytes, and when
* writing large chunks of data, they write 64-bytes at a time. Obviously, this
* improves write throughput.
*
* Also, the MTD device may have N interleaved (striped) flash chips
* underneath, in which case @min_io_size can be physical min. I/O size of
* single flash chip, while @max_write_size can be N * @min_io_size.
*
* The @max_write_size field is always greater or equivalent to @min_io_size.
* E.g., some NOR flashes may have (@min_io_size = 1, @max_write_size = 64). In
* contrast, NAND flashes usually have @min_io_size = @max_write_size = NAND
* page size.
*/
struct ubi_device_info {
int ubi_num;
int leb_size;
int leb_start;
int min_io_size;
int max_write_size;
int ro_mode;
dev_t cdev;
};