GeneveOS Memory Management Functions
Revision as of 14:44, 11 November 2011 by Mizapf (talk | contribs) (→Claim pages into local map from free pages)
Memory management in MDOS is available via XOP 7.
General purpose XOPs
Return number of free pages in system
Opcode: 0
| Input | Output | |
|---|---|---|
| R0 | Opcode (0000) | Error code (always 0) |
| R1 | Number of free pages | |
| R2 | Number of fast free pages |
Claim pages into local map from free pages
Opcode: 1
| Input | Output | |
|---|---|---|
| R0 | Opcode (0001) | Error code |
| R1 | Number of pages | Number of pages actually fetched to complete map as required |
| R2 | Local page address | Number of fast pages fetched |
| R3 | Speed flag (if not 0, only fast) |
Return pages into free pool from local map
Opcode: 2
| Input | Output | |
|---|---|---|
| R0 | Opcode (0002) | Error code |
| R1 | Number of pages | |
| R2 | Local page address |
Map local page at excution page
Opcode: 3
| Input | Output | |
|---|---|---|
| R0 | Opcode (0003) | Error code |
| R1 | Local page number | |
| R2 | Execution page number |
Get address map
Opcode: 4
| Input | Output | |
|---|---|---|
| R0 | Opcode (0004) | Error code |
| R1 | Execution address | Count of pages reported |
| R2 | Size of area for map |
Opcode: 5
| Input | Output | |
|---|---|---|
| R0 | Opcode (0005) | Error code |
| R1 | Number of pages to declare as shared | |
| R2 | Local page address | |
| R3 | Type to be assigned to shared pages |
Opcode: 6
| Input | Output | |
|---|---|---|
| R0 | Opcode (0006) | Error code |
| R1 | Type |
Also have to check their current execution map
Opcode: 7
| Input | Output | |
|---|---|---|
| R0 | Opcode (0007) | Error code |
| R1 | Type | |
| R2 | Local page number for start of shared area |
Opcode: 8
| Input | Output | |
|---|---|---|
| R0 | Opcode (0008) | Error code |
| R1 | Type | Number of pages in shared group |
Privileged XOPs (only available for operating system)
Release task
Opcode: 9
| Input | Output | |
|---|---|---|
| R0 | Opcode (0009) |
Task header at >8000
Page get
Opcode: 10
| Input | Output | |
|---|---|---|
| R0 | Opcode (000A) | Error code |
| R1 | Page number to get (if high byte not 0, get first available) | Pointer to node |
| R2 | Speed flag (0 is slow, else fast) | Page number from node |
Add page to free pages in system
Opcode: 11
| Input | Output | |
|---|---|---|
| R0 | Opcode (000B) | Error code (if no free nodes available) |
| R1 | Page number | Pointer to node |
Add a node to the list of free nodes
Opcode: 12
| Input | Output | |
|---|---|---|
| R0 | Opcode (000C) | Error code (always 0000) |
| R1 | Pointer to node |
Link a node to the specified node
Opcode: 13
| Input | Output | |
|---|---|---|
| R0 | Opcode (000D) | Error code (always 0000) |
| R1 | Pointer to node | |
| R2 | Pointer to node to link to |
Get address map (system)
Opcode: 14
| Input | Output | |
|---|---|---|
| R0 | Opcode (000E) | Count of valid pages |