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