diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
| commit | bbb20089a3275a19e475dbc21320c3742e3ca423 (patch) | |
| tree | 216fdc1cbef450ca688135c5b8969169482d9a48 /Documentation/ABI/testing/sysfs-block | |
| parent | 3e48e656903e9fd8bc805c6a2c4264d7808d315b (diff) | |
| parent | 657a77fa7284d8ae28dfa48f1dc5d919bf5b2843 (diff) | |
Merge branch 'dmaengine' into async-tx-next
Conflicts:
crypto/async_tx/async_xor.c
drivers/dma/ioat/dma_v2.h
drivers/dma/ioat/pci.c
drivers/md/raid5.c
Diffstat (limited to 'Documentation/ABI/testing/sysfs-block')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block index 44f52a4f5903..cbbd3e069945 100644 --- a/Documentation/ABI/testing/sysfs-block +++ b/Documentation/ABI/testing/sysfs-block @@ -60,3 +60,62 @@ Description: Indicates whether the block layer should automatically generate checksums for write requests bound for devices that support receiving integrity metadata. + +What: /sys/block/<disk>/alignment_offset +Date: April 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + Storage devices may report a physical block size that is + bigger than the logical block size (for instance a drive + with 4KB physical sectors exposing 512-byte logical + blocks to the operating system). This parameter + indicates how many bytes the beginning of the device is + offset from the disk's natural alignment. + +What: /sys/block/<disk>/<partition>/alignment_offset +Date: April 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + Storage devices may report a physical block size that is + bigger than the logical block size (for instance a drive + with 4KB physical sectors exposing 512-byte logical + blocks to the operating system). This parameter + indicates how many bytes the beginning of the partition + is offset from the disk's natural alignment. + +What: /sys/block/<disk>/queue/logical_block_size +Date: May 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + This is the smallest unit the storage device can + address. It is typically 512 bytes. + +What: /sys/block/<disk>/queue/physical_block_size +Date: May 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + This is the smallest unit the storage device can write + without resorting to read-modify-write operation. It is + usually the same as the logical block size but may be + bigger. One example is SATA drives with 4KB sectors + that expose a 512-byte logical block size to the + operating system. + +What: /sys/block/<disk>/queue/minimum_io_size +Date: April 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + Storage devices may report a preferred minimum I/O size, + which is the smallest request the device can perform + without incurring a read-modify-write penalty. For disk + drives this is often the physical block size. For RAID + arrays it is often the stripe chunk size. + +What: /sys/block/<disk>/queue/optimal_io_size +Date: April 2009 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + Storage devices may report an optimal I/O size, which is + the device's preferred unit of receiving I/O. This is + rarely reported for disk drives. For RAID devices it is + usually the stripe width or the internal block size. |