From 654b095d6fc18c7e900fccaf46c74f771db5478f Mon Sep 17 00:00:00 2001
From: Abdur-Rahman Mansoor <armansoor@missingno.dev>
Date: Thu, 6 Jun 2024 13:28:31 -0400
Subject: [PATCH] add assertions for `nvme_identify` and wip implementation of
 `create_namespace`

---
 drivers/nvme/nvme.asm | 56 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 50 insertions(+), 6 deletions(-)

diff --git a/drivers/nvme/nvme.asm b/drivers/nvme/nvme.asm
index 5102c4b..d79afa8 100644
--- a/drivers/nvme/nvme.asm
+++ b/drivers/nvme/nvme.asm
@@ -110,14 +110,41 @@ proc set_cdw0 stdcall, opcode:byte, cid:word
 
 endp
 
-proc nvme_identify stdcall, pci:dword, slot:dword, nsid:dword, dptr:dword, cid:word, cns:byte
+proc nvme_identify stdcall, pci:dword, nsid:dword, dptr:dword, cid:word, cns:byte
 
 		push 	esi
 		mov 	esi, [pci]
+
+		; It's important to check if CNS is a valid value here. In revision 1.0
+		; CNS is a 1 bit field and a two bit field in revision 1.1, using invalid
+		; values results in undefined behavior (see page 162 of NVMe 1.4 spec)
+		if __DEBUG__
+			push 	esi
+			mov 	esi, dword [esi + pcidev.mmio_ptr]
+			mov 	eax, dword [esi + NVME_MMIO.VS]
+			cmp 	eax, VS110
+			jne 	@f
+			cmp 	[cns], 11b
+			jle		.ok
+			DEBUGF  DBG_INFO, "(NVMe) FATAL ERROR: INVALID CNS VALUE ON v1.1.0 CONTROLLERS\n"
+			jmp 	.err
+		
+			@@:
+			cmp 	eax, VS100
+			jne 	.ok
+			cmp 	[cns], 1b
+			jle 	.ok
+			DEBUGF  DBG_INFO, "(NVMe) FATAL ERROR: INVALID CNS VALUE ON v1.0.0 CONTROLLERS\n"
+			jmp 	.err
+
+			.err:
+			jmp 	@b
+			
+			.ok:
+			
+		end if
+
 		mov 	esi, [esi + pcidev.sq_ptr]
-		mov 	eax, [slot]
-		imul 	eax, sizeof.SQ_ENTRY
-		add 	esi, eax
 		stdcall memset, esi, 0, sizeof.SQ_ENTRY
 
 		mov     eax, [nsid]
@@ -137,6 +164,22 @@ proc nvme_identify stdcall, pci:dword, slot:dword, nsid:dword, dptr:dword, cid:w
 
 endp
 
+; See pages 348-349 of the NVMe 1.4 specification for information on creating namespaces
+proc create_namespace stdcall, pci:dword, cid:word
+		
+		push 	esi
+		invoke  AllocPage
+		test 	eax, eax
+		jz 		.fail
+		invoke  GetPhysAddr
+		stdcall nvme_identify, [pci], 0xffffffff, eax, [cid], CNS_IDNS
+
+.fail:
+		pop 	esi
+		ret
+
+endp
+
 ; See page 101 of the NVMe 1.4 specification for reference
 proc create_io_completion_queue stdcall, pci:dword, prp1:dword, qid:word, ien:byte
 	
@@ -216,6 +259,7 @@ proc abort stdcall, pci:dword, cid:word, sqid:word
 
 endp
 
+
 ; See page 205 of the NVMe 1.4 specification for reference
 proc set_features stdcall, pci:dword, dptr:dword, fid:byte
 		
@@ -513,8 +557,8 @@ proc nvme_init stdcall, pci:dword
 		invoke  AllocPage
 		test 	eax, eax
 		jz 		.exit_fail
-		;                      pci:dword, slot:dword, nsid:dword, dptr:dword, cid:word, cns:byte
-		stdcall nvme_identify, [pci],     0,          0,          eax,        0,        CNS_IDCS
+		;                      pci:dword, nsid:dword, dptr:dword, cid:word, cns:byte
+		stdcall nvme_identify, [pci],     0,          eax,        0,        CNS_IDCS
 		
       	xor     eax, eax
       	inc     eax