Files
Aaru/Aaru.Decoders/SCSI/Modes/08.cs

322 lines
12 KiB
C#

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename : 08.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
// Decodes SCSI MODE PAGE 08h: Caching page.
//
// --[ License ] --------------------------------------------------------------
//
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2023 Natalia Portillo
// ****************************************************************************/
using System.Diagnostics.CodeAnalysis;
using System.Text;
namespace Aaru.Decoders.SCSI;
[SuppressMessage("ReSharper", "InconsistentNaming")]
[SuppressMessage("ReSharper", "MemberCanBeInternal")]
[SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
public static partial class Modes
{
#region Mode Page 0x08: Caching page
/// <summary>Disconnect-reconnect page Page code 0x08 12 bytes in SCSI-2 20 bytes in SBC-1, SBC-2, SBC-3</summary>
public struct ModePage_08
{
/// <summary>Parameters can be saved</summary>
public bool PS;
/// <summary><c>true</c> if write cache is enabled</summary>
public bool WCE;
/// <summary>Multiplication factor</summary>
public bool MF;
/// <summary><c>true</c> if read cache is enabled</summary>
public bool RCD;
/// <summary>Advices on reading-cache retention priority</summary>
public byte DemandReadRetentionPrio;
/// <summary>Advices on writing-cache retention priority</summary>
public byte WriteRetentionPriority;
/// <summary>If requested read blocks are more than this, no pre-fetch is done</summary>
public ushort DisablePreFetch;
/// <summary>Minimum pre-fetch</summary>
public ushort MinimumPreFetch;
/// <summary>Maximum pre-fetch</summary>
public ushort MaximumPreFetch;
/// <summary>Upper limit on maximum pre-fetch value</summary>
public ushort MaximumPreFetchCeiling;
/// <summary>Manual cache controlling</summary>
public bool IC;
/// <summary>Abort pre-fetch</summary>
public bool ABPF;
/// <summary>Caching analysis permitted</summary>
public bool CAP;
/// <summary>Pre-fetch over discontinuities</summary>
public bool Disc;
/// <summary><see cref="CacheSegmentSize" /> is to be used to control caching segmentation</summary>
public bool Size;
/// <summary>Force sequential write</summary>
public bool FSW;
/// <summary>Logical block cache segment size</summary>
public bool LBCSS;
/// <summary>Disable read-ahead</summary>
public bool DRA;
/// <summary>How many segments should the cache be divided upon</summary>
public byte CacheSegments;
/// <summary>How many bytes should the cache be divided upon</summary>
public ushort CacheSegmentSize;
/// <summary>How many bytes should be used as a buffer when all other cached data cannot be evicted</summary>
public uint NonCacheSegmentSize;
public bool NV_DIS;
}
public static ModePage_08? DecodeModePage_08(byte[] pageResponse)
{
if((pageResponse?[0] & 0x40) == 0x40)
return null;
if((pageResponse?[0] & 0x3F) != 0x08)
return null;
if(pageResponse[1] + 2 != pageResponse.Length)
return null;
if(pageResponse.Length < 12)
return null;
var decoded = new ModePage_08();
decoded.PS |= (pageResponse[0] & 0x80) == 0x80;
decoded.WCE |= (pageResponse[2] & 0x04) == 0x04;
decoded.MF |= (pageResponse[2] & 0x02) == 0x02;
decoded.RCD |= (pageResponse[2] & 0x01) == 0x01;
decoded.DemandReadRetentionPrio = (byte)((pageResponse[3] & 0xF0) >> 4);
decoded.WriteRetentionPriority = (byte)(pageResponse[3] & 0x0F);
decoded.DisablePreFetch = (ushort)((pageResponse[4] << 8) + pageResponse[5]);
decoded.MinimumPreFetch = (ushort)((pageResponse[6] << 8) + pageResponse[7]);
decoded.MaximumPreFetch = (ushort)((pageResponse[8] << 8) + pageResponse[9]);
decoded.MaximumPreFetchCeiling = (ushort)((pageResponse[10] << 8) + pageResponse[11]);
if(pageResponse.Length < 20)
return decoded;
decoded.IC |= (pageResponse[2] & 0x80) == 0x80;
decoded.ABPF |= (pageResponse[2] & 0x40) == 0x40;
decoded.CAP |= (pageResponse[2] & 0x20) == 0x20;
decoded.Disc |= (pageResponse[2] & 0x10) == 0x10;
decoded.Size |= (pageResponse[2] & 0x08) == 0x08;
decoded.FSW |= (pageResponse[12] & 0x80) == 0x80;
decoded.LBCSS |= (pageResponse[12] & 0x40) == 0x40;
decoded.DRA |= (pageResponse[12] & 0x20) == 0x20;
decoded.CacheSegments = pageResponse[13];
decoded.CacheSegmentSize = (ushort)((pageResponse[14] << 8) + pageResponse[15]);
decoded.NonCacheSegmentSize = (uint)((pageResponse[17] << 16) + (pageResponse[18] << 8) + pageResponse[19]);
decoded.NV_DIS |= (pageResponse[12] & 0x01) == 0x01;
return decoded;
}
public static string PrettifyModePage_08(byte[] pageResponse) =>
PrettifyModePage_08(DecodeModePage_08(pageResponse));
public static string PrettifyModePage_08(ModePage_08? modePage)
{
if(!modePage.HasValue)
return null;
ModePage_08 page = modePage.Value;
var sb = new StringBuilder();
sb.AppendLine(Localization.SCSI_Caching_mode_page);
if(page.PS)
sb.AppendLine("\t" + Localization.Parameters_can_be_saved);
if(page.RCD)
sb.AppendLine("\t" + Localization.Read_cache_is_enabled);
if(page.WCE)
sb.AppendLine("\t" + Localization.Write_cache_is_enabled);
switch(page.DemandReadRetentionPrio)
{
case 0:
sb.AppendLine("\t" + Localization.Drive_does_not_distinguish_between_cached_read_data);
break;
case 1:
sb.AppendLine("\t" +
Localization.
Data_put_by_READ_commands_should_be_evicted_from_cache_sooner_than_data_put_in_read_cache_by_other_means);
break;
case 0xF:
sb.AppendLine("\t" +
Localization.
Data_put_by_READ_commands_should_not_be_evicted_if_there_is_data_cached_by_other_means_that_can_be_evicted);
break;
default:
sb.AppendFormat("\t" + Localization.Unknown_demand_read_retention_priority_value_0,
page.DemandReadRetentionPrio).
AppendLine();
break;
}
switch(page.WriteRetentionPriority)
{
case 0:
sb.AppendLine("\t" + Localization.Drive_does_not_distinguish_between_cached_write_data);
break;
case 1:
sb.AppendLine("\t" +
Localization.
Data_put_by_WRITE_commands_should_be_evicted_from_cache_sooner_than_data_put_in_write_cache_by_other_means);
break;
case 0xF:
sb.AppendLine("\t" +
Localization.
Data_put_by_WRITE_commands_should_not_be_evicted_if_there_is_data_cached_by_other_means_that_can_be_evicted);
break;
default:
sb.AppendFormat("\t" + Localization.Unknown_demand_write_retention_priority_value_0,
page.DemandReadRetentionPrio).
AppendLine();
break;
}
if(page.DRA)
sb.AppendLine("\t" + Localization.Read_ahead_is_disabled);
else
{
if(page.MF)
sb.AppendLine("\t" + Localization.Pre_fetch_values_indicate_a_block_multiplier);
if(page.DisablePreFetch == 0)
sb.AppendLine("\t" + Localization.No_pre_fetch_will_be_done);
else
{
sb.AppendFormat("\t" + Localization.Pre_fetch_will_be_done_for_READ_commands_of_0_blocks_or_less,
page.DisablePreFetch).
AppendLine();
if(page.MinimumPreFetch > 0)
{
sb.AppendFormat(Localization.At_least_0_blocks_will_be_always_pre_fetched, page.MinimumPreFetch).
AppendLine();
}
if(page.MaximumPreFetch > 0)
{
sb.AppendFormat("\t" + Localization.A_maximum_of_0_blocks_will_be_pre_fetched,
page.MaximumPreFetch).
AppendLine();
}
if(page.MaximumPreFetchCeiling > 0)
{
sb.
AppendFormat("\t" + Localization.A_maximum_of_0_blocks_will_be_pre_fetched_even_if_it_is_commanded_to_pre_fetch_more,
page.MaximumPreFetchCeiling).
AppendLine();
}
if(page.IC)
{
sb.AppendLine("\t" +
Localization.
Device_should_use_number_of_cache_segments_or_cache_segment_size_for_caching);
}
if(page.ABPF)
sb.AppendLine("\t" + Localization.Pre_fetch_should_be_aborted_upon_receiving_a_new_command);
if(page.CAP)
sb.AppendLine("\t" + Localization.Caching_analysis_is_permitted);
if(page.Disc)
{
sb.AppendLine("\t" +
Localization.
Pre_fetch_can_continue_across_discontinuities_such_as_cylinders_or_tracks);
}
}
}
if(page.FSW)
sb.AppendLine("\t" + Localization.Drive_should_not_reorder_the_sequence_of_write_commands_to_be_faster);
if(page.Size)
{
if(page.CacheSegmentSize > 0)
{
if(page.LBCSS)
{
sb.AppendFormat("\t" + Localization.Drive_cache_segments_should_be_0_blocks_long,
page.CacheSegmentSize).
AppendLine();
}
else
{
sb.AppendFormat("\t" + Localization.Drive_cache_segments_should_be_0_bytes_long,
page.CacheSegmentSize).
AppendLine();
}
}
}
else
{
if(page.CacheSegments > 0)
{
sb.AppendFormat("\t" + Localization.Drive_should_have_0_cache_segments, page.CacheSegments).
AppendLine();
}
}
if(page.NonCacheSegmentSize > 0)
{
sb.
AppendFormat("\t" + Localization.Drive_shall_allocate_0_bytes_to_buffer_even_when_all_cached_data_cannot_be_evicted,
page.NonCacheSegmentSize).
AppendLine();
}
if(page.NV_DIS)
sb.AppendLine("\t" + Localization.Non_Volatile_cache_is_disabled);
return sb.ToString();
}
#endregion Mode Page 0x08: Caching page
}