Work

boot/boot.z80

@@ -1,4 +1,4 @@
-_start:
+_gtart:
 ld sp,0  ; Initialize the stack
 ld a,0x4 ; Find a generic storage card
 call find_first_card

config.toml

@@ -0,0 +1,14 @@
+[[cards]]
+type = "rom"
+image = "rom.bin"
+
+[[cards]]
+type = "term"
+
+[[cards]]
+type = "ram"
+num_pages = 128 # 512 KiB
+
+[[cards]]
+type = "storage"
+image = "os.dsk"

file_structures

@@ -0,0 +1,15 @@
+VFS messages:
+register_fs(mb_no: MailboxID, name: &str) -> bool
+mount(dev_path: &str, mount_path: &str, fs: &str) -> bool
+open(path: &str, mode: &str) -> (MailboxID, u32)
+
+FS Api:
+// Optional mailbox is redirect mailbox - direct file API calls there for provided FD
+open(path: &str, mode: &str) -> (Option<MailboxID>, u32)
+
+File Api:
+read(fd: u32, pos: usize, len: usize) -> Vec<u8>
+
+DevFS:
+register_dev(mb_no: MailboxID, name: &str, kind: u8) -> bool
+

init.z80

@@ -4,8 +4,6 @@ _start:
 call find_disk
 /* ld hl, test_string */
 /* call print */
-/* call get_free_mailbox ; Initialize a mailbox */
-/* ld (mailbox_num), hl */
 call get_free_frame ; Set up a frame to load programs into at 0x8000
 ld b, c
 ld e, l
@@ -13,6 +11,11 @@ ld d, h
 ld c, 8
 bp_call_sf:
 call set_frame
+; ld iy, vfs_name ; Load and run the initrd driver
+; call run_file
+; vfs_loaded:
+; call yield ; Yield to let the initrd driver initialize
+; vfs_returned:
 ld iy, initrd_driver_name ; Load and run the initrd driver
 call run_file
 initrd_driver_loaded:
@@ -21,47 +24,108 @@ initrd_driver_returned:
 ld iy, initrd_fs_name ; Load and run the initrd fs driver
 call run_file
 initrd_fs_loaded:
+fs_init_wait_loop:
 call yield ; Yield to let the initrd driver initialize
-/* call get_free_frame ; Set up a message frame at 0xA000 */
+yield_done:
-/* ld b, c */ 
+call get_free_mailbox ; Initialize a mailbox
-/* push hl */
+ld (mailbox_num), hl
-/* pop de */
+ld de, 1
-/* ld c, 0xA */
+call proc_map_get
-/* call set_frame */ 
+ld a, l
-; Set up a read message to the driver starting at 0x80 and reading
+cp 0
-; 0x200 bytes
+jp z, fs_init_wait_loop
-/* ld a, 0x80 */ 
+fs_ready:
-/* ld (0xA000), a */
+call get_free_frame ; Set up a message frame at 0xA000
-/* ld a, 0x00 */
+ld a, c
-/* ld (0xA001), a */
+ld (msg_phys_addr), a
-/* ld a, 0x00 */
+ld (msg_phys_addr+1), hl
-/* ld (0xA002), a */
+ld b, c 
-/* ld a, 0x2 */
+push hl
-/* ld (0xA003), a */
+pop de
-/* ld hl, (mailbox_num) */
+ld c, 0xA
-/* ld (0xA004), hl */
+call set_frame 
-/* push de */
+frame_done:
-/* push bc */
+; Set up an open message to the initrd FS for "init.elf"
-/* ld de, 0 ; Get the mailbox number for the initrd driver */
+ld hl, (mailbox_num)
-/* call proc_map_get */
+ld (0xA000), hl
-/* pop bc */
+ld a, 0x0 ; Open operation
-/* pop de */
+ld (0xA002), a
-/* ld c, b ; Send the message */
+ld a, 0x69 ; i
-/* ld ix, 0x0000 */
+ld (0xA003), a
-/* call mb_send */
+ld a, 0x6e ; n
-/* loop: */
+ld (0xA004), a
-/* call yield */
+ld a, 0x69 ; i
-/* ld hl, (mailbox_num) */
+ld (0xA005), a
-/* call mb_read ; Read a message */
+ld a, 0x74 ; t
-/* ld a, b ; Loop if there is no message */
+ld (0xA006), a
-/* cp 0 */
+ld a, 0x2e ; .
-/* jp nz, loop */
+ld (0xA007), a
+ld a, 0x65 ; e
+ld (0xA008), a
+ld a, 0x6c ; l
+ld (0xA009), a
+ld a, 0x66 ; f
+ld (0xA00a), a
+ld a, 0x0 ; NUL
+ld (0xA00b), a
+push de
+push bc
+ld de, 1 ; Get the mailbox number for the initrd driver
+call proc_map_get
+pmg_done:
+pop bc
+pop de
+ld c, b ; Send the message
+ld ix, 0x0000
+call mb_send
 loop:
 call yield
-jp loop
+loop_yield_done:
+ld hl, (mailbox_num)
+call mb_read ; Read a message
+mb_read_done:
+ld a, b ; Loop if there is no message
+cp 0
+jp nz, loop
+ld a, (0xA001)
+ld c, a
+open_done:
+; Set up a read message to the initrd FS for init.elf starting at 0x10 and reading 0x50 bytes 
+ld hl, (mailbox_num)
+ld (0xA000), hl
+ld a, 0x1 ; Read operation 
+ld (0xA002), a
+ld a, c ; FD
+ld (0xA003), a
+ld hl, 0x10
+ld (0xA004), hl ; File offset
+ld hl, 0x50
+ld (0xA006), hl ; Read length
+ld de, 1 ; Get the mailbox number for the initrd driver
+call proc_map_get
+read_pmg_done:
+ld a, (msg_phys_addr)
+ld c, a
+ld de, (msg_phys_addr+1)
+ld ix, 0x0000
+call mb_send
+read_loop:
+call yield
+read_loop_yield_done:
+ld hl, (mailbox_num)
+call mb_read ; Read a message
+read_mb_read_done:
+ld a, b ; Loop if there is no message
+cp 0
+jp nz, read_loop
+
+halt
 
 mailbox_num: .ds.b 2
 
+msg_phys_addr: .ds.b 3
+
+vfs_name: .asciz "vfs.elf"
 initrd_driver_name: .asciz "initrd_driver.elf"
 initrd_fs_name: .asciz "initrd_fs.elf"
 

initrd_driver.z80

@@ -2,20 +2,22 @@
 
 _start:
 call find_disk
-ld a, 7
+call get_free_mailbox
-call 0xdffd
 push hl
 ld de, 0
-ld a, 8
+pms_call:
-call 0xdffd
+call proc_map_set
 pop hl
 ld (mailbox_num), hl
 msg_loop:
 call yield
 yield_back:
 ld hl, (mailbox_num)
-ld a, 6
+call mb_read
-call 0xdffd
+mb_read_done:
+ld a, b
+cp 1
+jp z, msg_loop
 msg_read:
 push bc
 push de
@@ -23,6 +25,7 @@ push hl
 ld b, c
 ld c, 0xB
 call set_frame
+set_frame_done:
 ld a, h
 or 0xB0
 ld h, a
@@ -33,17 +36,17 @@ inc hl
 ld e, (hl)
 inc hl
 ld d, (hl)
+ld hl, (0xB004) ; Load destination mailbox into HL and save it on the stack
+push hl
 ld hl, 0xB000
-jp read_bytes
+call read_bytes
-ld hl, (0xB004) ; Load destination mailbox into HL
+pop hl
 pop ix
 pop de
 pop bc
 ld a, 5
 call 0xdffd
-halt
 jp msg_loop
-halt
 
 read_buf: .ds.b 512
 
@@ -67,24 +70,61 @@ ld a, (start_byte) ; A = 255 - offset + 1 (256-offset)
 ld b, a
 ld a, 0xFF
 sub b
-inc a
 ld b, 0 ; Load bc with the value in A
 ld c, a 
+inc bc
+push de
+ld de, (byte_count)
+ld a, b
+cp d
+jp c, count_ok_1
+ld a, c
+cp e
+jp c, count_ok_1
+push de
+pop bc
+count_ok_1:
+pop de
+ld a, b
+cp 0
+jp nz, nz_ok
+ld a, c
+cp 0
+jp nz, nz_ok
+jp no_transfer
+nz_ok:
 ldir  
+no_transfer:
 start_sec_trns_done:
 ld (dest_addr), de
 ld a, (start_byte) ; A = 255 - offset + 1 (256-offset)
 ld b, a
 ld a, 0xFF
 sub b
-inc a
 ld b, 0 ; Load bc with the value in A
 ld c, a 
+inc bc
+push de
+ld de, (byte_count)
+ld a, b
+cp d
+jp c, count_ok_2
+ld a, c
+cp e
+jp c, count_ok_2
+push de
+pop bc
+count_ok_2:
+pop de
+
 ld hl, (byte_count)
 scf
 ccf
 sbc hl, bc
 ld (rem_bytes), hl
+ld a, h
+cp 0
+jp z, no_transfer_2
 ld b, h
 ld c, 0
 ld d, 0
@@ -98,6 +138,10 @@ call read_sector
 inc de
 pop bc
 djnz sector_loop
+no_transfer_2:
+ld a, (rem_bytes)
+cp 0
+jp z, read_bytes_done
 ld (dest_addr), hl
 ld hl, (sec_buf)
 call read_sector

initrd_fs.z80

@@ -1,47 +1,61 @@
 .global _start
 _start:
 call get_free_mailbox ; Get a mailbox
+ld (sec_read_mailbox_num), hl
+call get_free_mailbox ; Get a mailbox
 ld (mailbox_num), hl
 ld de, 1
-call get_free_frame ; Set up a frame to send messages at 0x8000
+call get_free_frame ; Set up a frame to send messages at 0xA000
-ld b, c
+ld a, c
-ld e, l
+ld (msg_frame_phys), a
-ld d, h
+ld a, l
-ld c, 0x8
+ld (msg_frame_phys+1), a
-call set_frame
+ld a, h
-call get_free_frame ; Set up a frame for the file mapping at 0xA000
+ld (msg_frame_phys+2), a
 ld b, c
 ld e, l
 ld d, h
 ld c, 0xA
 call set_frame
+call get_free_frame ; Set up a frame for the file mapping at 0x8000
+ld b, c
+ld e, l
+ld d, h
+ld c, 0x8
+call set_frame
 ld c, 0
 ld de, 1
-ld hl, 0xA000
+ld hl, 0x8000
 initrd_read_loop:
 push bc
 push de
 push hl
-ld hl, 0x8000
+; FM SECL SECH
+ld hl, 0xA000
 call read_sector
 pop de
 push de
+; FM SECL SECH
 ld b, 0 ; Load the filename length in BC
-ld a, (0x8000)
+ld a, (0xA000)
+cp 0
+jp z, initrd_read_done
 ld c, a 
-ld hl, 0x8001
+ld hl, 0xA001 ; Read the name + null terminator into the mapping list
 ldir
 ld a, (hl)
 ld (de), a
 inc hl
-pop de
+ pop de ; Restore the value of DE before reading the name in
-ld a, e
+; SECL SECH
+dbg_label:
+ld a, e ; Add 0x20 to DE
 add a, 0x20
 ld e, a
 ld a, d
 adc a, 0x0
 ld d, a
-ld a, (hl)
+ld a, (hl) ; Write the file legth to the mapping list
 ld (de), a
 inc hl
 inc de
@@ -51,9 +65,17 @@ inc hl
 inc de
 ld l, e 
 ld h, d
-pop de
+pop iy
+; SECH
 pop bc
-ld (hl), e
+; (EMPTY) 
+push de
+; FM 
+push bc
+; SECH FM
+ld e, iyl
+ld d, iyh
+ld (hl), e ; Write the starting block of the file to the mapping list
 inc hl
 ld (hl), d
 inc hl
@@ -61,9 +83,9 @@ ld (hl), c
 inc hl
 ; Advance to the next header
 ld b, 0 ; Load the filename length in BC
-ld a, (0x8000)
+ld a, (0xA000)
 ld c, a 
-ld hl, 0x8004
+ld hl, 0xA004
 add hl, bc ; Add the filename length to get the pointer to the
 ; # of blocks in the file in HL
 ld c, (hl) ; Read the # of blocks into BC
@@ -73,37 +95,161 @@ ld l, c ; Move it into HL
 ld h, b
 inc hl ; Add 1 to account for the header sector
 pop bc
+; FM
 add hl, de ; 24-bit add of HL to C:DE
 ld e, l
 ld d, h
 ld a, c
 adc a, 0
 ld c, a
+pop hl
+; (empty)
+inc hl
+inc hl
+inc hl
 jp initrd_read_loop
+initrd_read_done:
+ld de, 1
+ld hl, (mailbox_num)
+pms_call:
 call proc_map_set ; Register ourselves as ID 1
 msg_loop:
 call yield
+yield_back:
 ld hl, (mailbox_num)
-call mb_read ; Read a message and place it at 0xB000
+call mb_read
+mb_read_done:
+ld a, b
+cp 1
+jp z, msg_loop
+msg_read:
 push bc
 push de
 push hl
 ld b, c
 ld c, 0xB
 call set_frame
-
+set_frame_done:
-ld hl, (0xB004) ; Load destination mailbox into HL
+ld hl, (0xB000) ; Load destination mailbox into HL and save it on the stack
+push hl
+ld hl, 0xB002
+; Handling code goes here
+ld a, (hl)
+inc hl
+cp 0x0
+jp z, open
+cp 0x1
+jp z, read
+operation_done:
+pop hl
 pop ix
 pop de
 pop bc
 call mb_send
-halt
 jp msg_loop
-halt
 
+; de = start of file map list
+; c = 0
+; while (1) {
+;   if (*de == 0) {
+;     (0xB000) = 1;
+;     return        
+;   }
+;   if (strcmp(de, 0xB003) == 0) {
+;      (0xB000) = 0;
+;      (0xB001) = c;
+;      return;
+;  }
+; }
+open:
+ld de, 0x8000
+ld c, 0
+open_find_loop:
+ld a, (de)
+cp 0
+jp nz, open_not_end
+ld a, 1
+ld (0xB000), a
+jp operation_done
+open_not_end:
+ld ix, 0xB003
+push de
+pop iy
+call strcmp
+cp 0
+jp nz, open_not_match
+ld a, 0
+ld (0xB000), a
+ld a, c
+ld (0xB001), a
+jp operation_done
+open_not_match:
+inc c
+push de
+pop hl
+ld de, 0x25
+add hl, de
+push hl
+pop de
+jp open_find_loop
+
+read:
+ld a, (0xB003)
+ld l, a
+ld h, 0
+push hl
+pop ix
+add hl, hl
+add hl, hl
+push hl
+pop de
+add ix, de
+add hl, hl
+add hl, hl
+add hl, hl
+push hl
+pop de
+add ix, de
+ld de, 0x8020
+add ix, de
+ld d, (ix+2)
+ld e, 0x0
+ld hl, (0xB004)
+add hl, de
+ld bc, 0x100
+add hl, bc
+ld c, l
+ld b, h
+ld de, (0xB006)
+call read_bytes
+ld de, 0xB000
+ld hl, 0xA000
+ld bc, (0xB006)
+ldir
+jp operation_done
+
+
+
+strcmp:
+strcmp_loop:
+ld a, (ix+0)
+ld b, (iy+0)
+cp b
+jp nz, strcmp_different
+cp 0
+ret z
+inc ix
+inc iy
+jp strcmp_loop
+strcmp_different:
+ld a, 1
+ret
+
+sec_read_mailbox_num: .ds.b 2
 mailbox_num: .ds.b 2
+msg_frame_phys: .ds.b 3
 
-; Given a sector number in C:DE, reads the sector off disk into 0x8000
+; Given a sector number in C:DE, reads the sector off disk into 0xA000
 read_sector:
 ; Set up a read message to the driver starting at the sector in register E and reading
 ; 0x100 bytes
@@ -115,23 +261,48 @@ ld a, 0x00
 ld (0xA002), a
 ld a, 0x1
 ld (0xA003), a
-ld hl, (mailbox_num)
+ld hl, (sec_read_mailbox_num)
 ld (0xA004), hl
-push de
-push bc
 ld de, 0 ; Get the mailbox number for the initrd driver
 call proc_map_get
-pop bc
+read_sec_pmg_done:
-pop de
+ld a, (msg_frame_phys)
-ld c, b ; Send the message
+ld c, a
-ld ix, 0x0000
+ld de, (msg_frame_phys + 1)
+ld ix, 0
 call mb_send
+read_sec_msg_sent:
 loop:
 call yield
-ld hl, (mailbox_num)
+ld hl, (sec_read_mailbox_num)
+read_sector_done:
+ret
+
+
+; Given a byte offset in BC, and a byte length in DE no more than 0x1000, reads the data off disk into 0xA000
+read_bytes:
+; Set up a read message to the driver starting at the sector in register E and reading
+; 0x100 bytes
+ld (0xA000), bc
+ld (0xA002), de
+ld hl, (sec_read_mailbox_num)
+ld (0xA004), hl
+ld de, 0 ; Get the mailbox number for the initrd driver
+call proc_map_get
+read_bytes_pmg_done:
+ld a, (msg_frame_phys)
+ld c, a
+ld de, (msg_frame_phys + 1)
+ld ix, 0
+call mb_send
+read_bytes_msg_sent:
+read_bytes_loop:
+call yield
+ld hl, (sec_read_mailbox_num)
+
 call mb_read ; Read a message
 ld a, b ; Loop if there is no message
 cp 0
-jp nz, loop
+jp nz, read_bytes_loop
-read_sector_done:
+read_bytes_done:
 ret

kernel/ipc.z80

@@ -154,6 +154,9 @@ ld (mb_free_list), a
 ld a, (ix + 1)
 ld (mb_free_list + 1), a
 ld hl, (temp)
+xor a
+ld (temp), a
+ld (temp + 1), a
 ret
 
 ; Clobbers A, BC, DE, and IX

kernel/main.z80

@@ -105,6 +105,7 @@ djnz page_alloc_loop
 pop de
 pop ix
 pop iy
+load_seg:
 ;Zero out the segments place in memory
 ld c, (ix+20) ; Load the byte counter with the number of bytes to zero out
 ld b, (ix+21)

kernel/pmem.z80

@@ -56,6 +56,7 @@ get_ram_bmap:
   ld a, h
   or 0xE0
   ld h, a
+  grb_512k_done:
   ret
   grb_large_card:
   ex af, af'
@@ -65,6 +66,7 @@ get_ram_bmap:
   ld e, d
   call set_frame
   ld hl, 0xE000
+  grb_large_done:
   ret
 
 ; Get a free frame of RAM
@@ -221,6 +223,8 @@ init_if1_end:
 /* cp c */
 jp nz, init_if2_end
 ld (hl), 0xFF
+inc hl
+ld (hl), 0xFF
 init_if2_end:
 ld a, (first_ram_card)
 ld b, a

kernel/proc_map.z80

@@ -8,6 +8,17 @@ call get_free_frame
 ld a, c
 ld (map_frame), a
 ld (map_frame+1), hl
+ld c, 0xE
+ld a, (map_frame)
+ld b, a
+ld de, (map_frame+1)
+call set_frame
+xor a
+ld (0xE000), a
+ld hl, 0xE000
+ld de, 0xE001
+ld bc, 4096-1
+ldir
 ret
 
 ; Clobbers A, BC, HL, IX
@@ -24,7 +35,7 @@ pop de
 pop hl
 add hl, hl
 ld a, h
-or 0xE
+or 0xE0
 ld h, a
 ld (hl), e
 inc hl
@@ -43,7 +54,7 @@ call set_frame
 pop hl
 add hl, hl
 ld a, h
-or 0xE
+or 0xE0
 ld h, a
 ld e, (hl)
 inc hl

kernel/tasking.z80

@@ -129,20 +129,13 @@ schedule_process:
         jp nz, block1
         jp end1
 block1:
-        push bc
         push hl
-        pop bc
-        call get_process_ptr
         push bc
-        pop iy
-        pop bc
-        push bc
-        /* ld (iy+7), c */
-        /* ld (iy+8), b */
         call get_process_ptr
         push bc
         pop ix
         pop bc
+        pop hl
         ld (ix+5), l
         ld (ix+6), h
         ld (ready_to_run_head), bc
@@ -158,6 +151,7 @@ end1:
         jp block3
 block2:
         ld (ready_to_run_head), bc
+        ld (ready_to_run_tail), bc
         ret
 block3:
         ld (current_process), bc
@@ -194,6 +188,7 @@ end3:
         push iy
         ld bc, (current_process)
         call get_process_ptr
+        yield_store_pm_gpp_done:
         push bc
         pop ix
         ld de, 11
@@ -211,51 +206,39 @@ yield_list_manip:
         ; Get next process into ix, unlink it from the
         ; ready to run list, and link the current process in
         ; Logic:
-        ; next_process = ready_to_run_head -> pid
+        ; next_process = ready_to_run_head
-        ; if (current_process->pid == 1) {
+        ; if (current_process == 1) {
         ;   ready_to_run_head = 0
+        ;   ready_to_run_tail = 0
         ; } else {
-        ; current_process->next = ready_to_run_head->next
+        ;   ready_to_run_head = ready_to_run_head->next
-        ; ready_to_run_head = current_process
+        ;   current_process->next = 0
+        ;   if (ready_to_run_head==0) {
+        ;     ready_to_run_head=current_process;
+        ;     ready_to_run_tail=current_process;
+        ;   } else {
+        ;     ready_to_run_tail->next = current_process
+        ;     ready_to_run_tail = current_process;
+        ;   }
         ; }
         ; current_process = next_process 
-        ld ix, (ready_to_run_head)
+        call pop_rtr_head
-        push ix
-        pop bc
-        call get_process_ptr
-ylm_gpp_done:
-        push bc
-        pop ix
-        ld e, (ix+9)
-        ld d, (ix+10)
-        ld l, (ix+5)
-        ld h, (ix+6)
-        push hl
-        push de
-        push ix
         ld bc, (current_process)
-        call get_process_ptr
+        ld a, c
-ylm_gpp2_done:
-        pop ix
-        pop de
-        pop hl
-        push bc
-        pop iy
-        ld a, (iy + 9)
         cp 1
-        jp nz, else4
+        jp z, ylm_skip_link
-        xor a
+        push de
-        ld (ready_to_run_head), a
+        call push_rtr_tail
-        ld (ready_to_run_head+1), a
+        pop de
-        jp end4
+ylm_skip_link:
-else4:
-        ld (iy+5), l
-        ld (iy+6), h
-        ld bc, (current_process)
-        ld (ready_to_run_head), bc
-end4:
         ld (current_process), de
 yield_sp_page_set:
+        push de
+        pop bc
+        call get_process_ptr
+y_sp_ps_gpp_done:
+        push bc
+        pop ix
         push ix
         ld de, 11
         add ix, de
@@ -303,7 +286,85 @@ yield_sp_load:
         pop af
         ret
 
+;Gets the ID of the head of the ready to run list in DE and removes the element from the list
+;Logic:
+        ; bc = *ready_to_run_head;
+        ; ix = get_process_ptr(bc);
+        ; ready_to_run_head = ix->next;
+        ; if (ready_to_run_head==0) {
+        ;       ready_to_run_tail=0;
+        ; }
+        ; return bc;
+pop_rtr_head:
+        ld bc, (ready_to_run_head)
+        push bc
+        call get_process_ptr
+pop_rh_gpp_done:
+        push bc
+        pop ix
+        pop de
+        ld l, (ix+5)
+        ld h, (ix+6)
+        ld (ready_to_run_head), hl
+        ld a, l
+        cp 0
+        jp nz, pop_rh_ok
+        ld a, h
+        cp 0
+        jp nz, pop_rh_ok
+        ld (ready_to_run_tail), hl
+pop_rh_ok:
+        ret
+
+;Pushes the process with the ID in BC onto the ready to run list
+; Clobbers A, DE, HL, and IX
+; Logic:
+        ; if (*ready_to_run_tail == 0) {
+        ;       *ready_to_run_tail = bc
+        ;       *ready_to_run_head = bc
+        ; } else {
+        ;       ix = get_process_ptr(bc);
+        ;       ix->next = 0;
+        ;       ix = get_process_ptr(*ready_to_run_tail);
+        ;       ix->next = bc;
+        ;       *ready_to_run_tail=bc;
+        ; }
+push_rtr_tail:
+        ld hl, (ready_to_run_tail)
+        ld a, l
+        cp 0
+        jp nz, push_rtr_tail_nz
+        ld a, h
+        cp 0
+        jp nz, push_rtr_tail_nz
+        ld (ready_to_run_head), bc
+        ld (ready_to_run_tail), bc
+        ret
+push_rtr_tail_nz:
+        push bc
+        call get_process_ptr
+push_rtr_gpp_done:
+        push bc
+        pop ix
+        ld (ix+5), 0
+        ld (ix+6), 0
+        ld bc, (ready_to_run_tail)
+        call get_process_ptr
+push_rtr_gpp2_done:
+        push bc
+        pop ix
+        pop bc
+        ld (ix+5), c
+        ld (ix+6), b
+        ld (ready_to_run_tail), bc
+        ret
+
+
+
+
+
 ready_to_run_head: .ds.b 2
+ready_to_run_tail: .ds.b 2
 current_process: .ds.b 2
 next_pid: .dc.w 1
 process_allocation_bitmap: .ds.b 128

vfs.z80

@@ -0,0 +1,220 @@
+.global _start
+
+_start:
+call get_free_frame
+ld b, c
+ld e, l
+ld d, h
+ld c, 0x9
+call set_frame
+call get_free_frame
+ld a, c
+ld (send_page_addr), a
+ld (send_page_addr+1), hl
+ld b, c
+ld e, l
+ld d, h
+ld c, 0x8
+call set_frame
+ld hl, 0x9000
+ld de, 0x9001
+ld bc, 0x1000
+ld (hl), 0x0
+ldir
+call get_free_mailbox
+push hl
+ld de, 1
+call proc_map_set
+pop hl
+ld (vfs_mailbox_num), hl
+call get_free_mailbox
+ld (fs_mailbox_num), hl
+msg_loop:
+call yield
+yield_back:
+ld hl, (vfs_mailbox_num)
+call mb_read
+mb_read_done:
+ld a, b
+cp 1
+jp z, msg_loop
+msg_read:
+push bc
+push de
+push hl
+ld b, c
+ld c, 0xB
+call set_frame
+set_frame_done:
+ld hl, (0xB000) ; Load destination mailbox into HL and save it on the stack
+push hl
+ld hl, 0xB002
+; Handling code goes here
+ld a, (hl)
+inc hl
+cp 0x0
+jp z, register_fs
+cp 0x1
+jp z, mount
+operation_done:
+pop hl
+pop ix
+pop de
+pop bc
+call mb_send
+jp msg_loop
+
+register_fs:
+ld a, (fs_count)
+ld l, a
+ld h, 0x0
+add hl, hl
+add hl, hl
+add hl, hl
+add hl, hl
+ld de, data_fs_offset
+add hl, de
+ld de, 0x9000
+add hl, de
+push hl
+pop de
+ld hl, 0xB003
+ld bc, 16
+ldir
+ld a, (fs_count)
+inc a
+ld (fs_count), a
+ret
+
+; String pointer 1 in IX, 2 in IY
+; Return in A
+strcmp:
+strcmp_loop:
+ld a, (iy)
+ld b, a
+ld a, (ix)
+cp b
+jp nz, strcmp_loopend
+cp 0
+ret z
+inc ix
+inc iy
+jp strcmp_loop
+strcmp_loopend:
+ld a, (iy)
+ld b, a
+ld a, (ix)
+sub b
+ret
+
+
+mount:
+ld a, (mount_count)
+ld l, 0x0
+ld h, a
+ld de, data_mount_offset
+add hl, de
+ld de, 0x9000
+add hl, de
+push hl
+pop de
+push de
+ld hl, 0xB003
+ld bc, 252
+ldir
+ld a, (mount_count)
+inc a
+ld (mount_count), a
+; FS type at 0xB1FF
+ld a, (fs_count)
+ld b, a
+ld hl, data_fs_offset + 0x9000
+ld de, 0x10
+mount_loop1:
+push hl
+pop ix
+ld iy, 0xB0FF
+push bc
+call strcmp
+pop bc
+cp 0
+jp mount_loop1_done
+add hl, de
+djnz mount_loop1
+mount_loop1_done:
+ld de, 14
+add hl, de
+pop ix
+ld de, 252
+add ix, de
+ld e, (hl)
+inc hl
+ld d, (hl)
+ld (ix), e
+ld (ix+1), d
+push ix
+ld a, 0x2
+ld (0x8000), a
+ld hl, 0xB0FF
+ld de, 0x8001
+ld bc, 256
+ldir
+ld a, (send_page_addr)
+ld c, a
+ld de, (send_page_addr+1)
+ld ix, 0x0
+call mb_send
+mount_wait_loop:
+call yield
+ld hl, (fs_mailbox_num)
+call mb_read ; Read a message
+ld a, b ; Loop if there is no message
+cp 0
+jp nz, mount_wait_loop
+pop ix
+ld a, (0x8000)
+ld (ix+2), a
+ld a, (0x8001)
+ld (ix+3), a
+
+ret  
+
+; String pointer 1 in IX, 2 in IY
+; Return in A
+vfsstrcmp:
+vfsstrcmp_loop:
+ld a, (iy)
+ld b, a
+ld a, (ix)
+cp b
+cp 0
+ret z
+jp nz, vfsstrcmp_loopend
+inc ix
+inc iy
+jp vfsstrcmp_loop
+vfsstrcmp_loopend:
+ld a, (iy)
+ld b, a
+ld a, (ix)
+sub b
+ret
+
+  
+
+
+vfs_mailbox_num: .ds.b 2
+fs_mailbox_num: .ds.b 2
+
+send_page_addr: .ds.b 3
+
+fs_count: .ds.b 1
+mount_count: .ds.b 1
+
+.equ data_fs_offset, 0x0
+.equ data_mount_offset, 0x200
+.equ fs_name_offset, 0x0 
+.equ fs_pid_offset, 0xE
+.equ mount_path_offset, 0x0
+.equ mount_fs_pid_offset, 0xFD
+.equ mount_fs_id_offset, 0xFF