scsi: ufs: core: Increase the maximum data buffer size
Measurements for one particular UFS controller + UFS device show a 25% higher read bandwidth if the maximum data buffer size is increased from 512 KiB to 1 MiB. Hence increase the maximum size of the data buffer associated with a single request from SCSI_DEFAULT_MAX_SECTORS (1024) * 512 bytes = 512 KiB to 1 MiB. Notes: - The maximum data buffer size supported by the UFSHCI specification is 65535 * 256 KiB or about 16 GiB. - The maximum data buffer size for READ(10) commands is 65535 logical blocks. To transfer more than 65535 * 4096 bytes = 255 MiB with a single SCSI command, the READ(16) command is required. Support for READ(16) is optional in the UFS 3.1 and UFS 4.0 standards. Link: https://lore.kernel.org/r/20220726225232.1362251-1-bvanassche@acm.org Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Avri Altman <avri.altman@wdc.com> Cc: Bean Huo <beanhuo@micron.com> Cc: Stanley Chu <stanley.chu@mediatek.com> Tested-by: Avri Altman <avri.altman@wdc.com> Acked-by: Avri Altman <avri.altman@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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