From ca5ccaa86b5a3d1ea16c0677641534f4e1020634 Mon Sep 17 00:00:00 2001
From: Abdur-Rahman Mansoor <armansoor@missingno.dev>
Date: Thu, 20 Jun 2024 18:14:28 -0400
Subject: [PATCH] refactor(nvme_init): use separately allocated queue pointers
 instead of using `dptr`

---
 drivers/nvme/nvme.asm | 42 +++++++++++++++++++++++++-----------------
 1 file changed, 25 insertions(+), 17 deletions(-)

diff --git a/drivers/nvme/nvme.asm b/drivers/nvme/nvme.asm
index 2aea64d..1c331b2 100644
--- a/drivers/nvme/nvme.asm
+++ b/drivers/nvme/nvme.asm
@@ -511,7 +511,7 @@ proc nvme_init stdcall, pci:dword
 
 		; we want to disable all interrupts for now, since the controller randomly
 	    ; generates interrupts while starting up
-		mov 	dword [edi + NVME_MMIO.INTMS], 0xffffffff 
+		;mov 	dword [edi + NVME_MMIO.INTMS], 0xffffffff 
 
 		; Attach interrupt handler
 		movzx 	eax, byte [esi + pcidev.iline]
@@ -523,45 +523,45 @@ proc nvme_init stdcall, pci:dword
 
 		; Restart the controller
 		stdcall nvme_controller_start, edi
-		mov 	dword [edi + NVME_MMIO.INTMC], 0xffffffff ; re-enable interrupts
+		;mov 	dword [edi + NVME_MMIO.INTMC], 0xffffffff ; re-enable interrupts
 
 		invoke  KernelAlloc, 0x1000
 		test 	eax, eax
 		jz 		.exit_fail
-		mov 	dword [dptr], eax
+		mov 	ebx, eax
 		invoke  GetPhysAddr
 		;                      pci:dword, nsid:dword, dptr:dword, cns:byte
 		stdcall nvme_identify, [pci],     0,          eax,        CNS_IDCS
 		stdcall nvme_cmd_wait, [pci], 0, 0
-		mov 	edx, dword [dptr]
-		lea 	edx, byte [edx + IDENTC.sn]
+		mov 	edi, ebx
+		lea 	ebx, byte [edi + IDENTC.sn]
 		lea 	eax, byte [esi + pcidev.serial]
-		stdcall memcpy, eax, edx, 20
+		stdcall memcpy, eax, ebx, 20
 		DEBUGF  DBG_INFO, "(NVMe) Serial Number: %s\n", eax
-		add 	edx, 20
+		add 	ebx, 20
 		lea 	eax, byte [esi + pcidev.model]
-		stdcall memcpy, eax, edx, 40
+		stdcall memcpy, eax, ebx, 40
 		DEBUGF  DBG_INFO, "(NVMe) Model: %s\n", eax
-		mov 	ebx, dword [esi + pcidev.version]
-		mov 	esi, dword [dptr]
+		mov 	edx, dword [esi + pcidev.version]
 		
-		cmp 	ebx, VS140
+		cmp 	edx, VS140
 		jl 		@f
 		; This is a reserved field in pre-1.4 controllers
-		mov 	al, byte [esi + IDENTC.cntrltype]
+		mov 	al, byte [edi + IDENTC.cntrltype]
 		cmp 	al, CNTRLTYPE_IO_CONTROLLER
 		jne 	.exit_fail 	
 		DEBUGF  DBG_INFO, "(NVMe) I/O controller detected...\n"
 
 @@:
-		mov 	al, byte [esi + IDENTC.sqes]
+		mov 	al, byte [edi + IDENTC.sqes]
 		and 	al, 11110000b
 		cmp 	al, 0x60 ; maximum submission queue size should at least be 64 bytes
 		jl 		.exit_fail
-		mov 	al, byte [esi + IDENTC.cqes]
+		mov 	al, byte [edi + IDENTC.cqes]
 		and 	al, 11110000b
 		and 	al, 0x40 ; maximum completion queue entry size should at least be 16 bytes
 		jl 		.exit_fail
+		invoke  KernelFree, edi
 
 		mov 	eax, (NVM_ASQS - 1) or ((NVM_ACQS - 1) shl 16) ; CDW11 (set the number of queues we want)
 		stdcall set_features, [pci], NULLPTR, FID_NUMBER_OF_QUEUES, eax
@@ -578,10 +578,19 @@ proc nvme_init stdcall, pci:dword
 		jnz		.exit_fail
 
 		; Create I/O Queues
-		mov 	eax, dword [dptr]
+		mov 	esi, [pci]
+		mov 	esi, dword [esi + pcidev.queue_entries]
+		lea 	esi, [esi + sizeof.NVM_QUEUE_ENTRY]
+		invoke  KernelAlloc, 0x1000
+		test 	eax, eax
+		jz 		.exit_fail
+		mov 	dword [esi + NVM_QUEUE_ENTRY.cq_ptr], eax
 		invoke 	GetPhysAddr
 		stdcall create_io_completion_queue, [pci], eax, 1, IEN_ON
-		mov 	eax, dword [dptr]
+		invoke  KernelAlloc, 0x1000
+		test 	eax, eax
+		jz 		.exit_fail
+		mov 	dword [esi + NVM_QUEUE_ENTRY.sq_ptr], eax
 		invoke 	GetPhysAddr
 		stdcall create_io_submission_queue, [pci], eax, 1, 1
 		
@@ -880,7 +889,6 @@ endp
 align 4
 		p_nvme_devices dd 0
 		pcidevs_len  dd 0
-		dptr 		 dd ?
 		my_service   db "NVMe",0  ;max 16 chars include zero
 		if __DEBUG__
 		include_debug_strings