removed another bad file

src/driver/storage/AHCI/notes.md

@@ -1,58 +0,0 @@
-# AHCI Driver Notes
-
-## Pre-scheduling / Process Kill Hazards
-
-### 1. Dangling DMA Buffer (critical)
-When a process is killed, its `kalloc`'d buffers get freed. But the AHCI hardware
-is still DMA'ing into that physical memory. The DMA write lands on whatever now
-occupies that memory, silently corrupting the kernel heap or another process.
-
-**Fix:** Before freeing a process's memory, either:
-- Wait for all its pending AHCI slots to drain (`cmd_issue` bits clear), or
-- Issue a port reset to abort in-flight commands, *then* free memory.
-
-### 2. Dangling Completion Callback / Userdata Pointer (critical)
-In `storage_read`/`storage_write`, the completion callback writes to `@done` —
-a **stack-local variable**. If the scheduler preempts or kills the process while
-it's in the `hlt` loop, that stack frame is gone. The ISR fires and writes to a
-dangling stack address, corrupting whatever now uses that stack page.
-
-**Fix:** The `done` flag and completion context must be heap-allocated (or in a
-kernel-owned structure that outlives the process). A per-request struct like:
-```pascal
-type TPendingIO = record
-    done     : uint32;
-    ownerPID : uint32;  { skip delivery if process is dead }
-end;
-```
-
-### 3. Command Slot Leak
-If a process is killed with pending I/O, `pending[slot].inUse` stays `true`
-forever. Eventually all 32 slots fill up and the device becomes unusable.
-
-**Fix:** When killing a process, scan all AHCI devices for `pending[]` entries
-belonging to that process, and either:
-- Let the hardware finish but null out the completion callback (ISR just frees slot), or
-- Abort the command (port reset) and clear the slot.
-
-### 4. Interrupt-Disabled Preemption
-The `asm sti` before the `hlt` loop is fine, but if the timer fires during setup
-(between `readCallbackAsync(...)` and `asm sti`), the process could be switched
-out with interrupts in an unexpected state. `hlt` is also not preemption-safe.
-
-**Fix:** Move to a proper wait-queue/sleep mechanism instead of `hlt`.
-
-## Recommended Path Forward
-Implement a small **I/O request queue** owned by the kernel (not the process stack):
-1. Allocate a request struct
-2. Put it on a per-device queue
-3. ISR completes it
-4. Process kill walks the queue and cancels entries for that PID
-
-## Other Bugs Fixed (2026-03-03)
-- **vtop mask bug:** `$FFFFFF` (24-bit) → `$3FFFFF` (22-bit) for 4MB page offset
-- **find_cmd_slot:** Now checks `pending[].inUse` in addition to `cmd_issue` bit
-- **Missing lba5:** Both `send_read_dma_async` and `send_write_dma_async` now write all 48 LBA bits
-- **IOAPIC routing:** PCI interrupts routed through IOAPIC so AHCI interrupts actually reach the CPU
-- **LAPIC EOI:** `ISR_N` now sends LAPIC EOI for IOAPIC-delivered interrupts
-- **PxIS pre-clear removed:** No longer blanket-clears port interrupt status before issuing commands (was eating other slots' completions)