diff --git a/bootmain.c b/bootmain.c
index a97271f..dde3454 100644
--- a/bootmain.c
+++ b/bootmain.c
@@ -33,8 +33,8 @@
 #define SECTSIZE	512
 #define ELFHDR		((struct elfhdr *) 0x10000) // scratch space
 
-void readsect(void*, uint32_t);
-void readseg(uint32_t, uint32_t, uint32_t);
+void readsect(void*, uint);
+void readseg(uint, uint, uint);
 
 void
 cmain(void)
@@ -42,14 +42,14 @@ cmain(void)
 	struct proghdr *ph, *eph;
 
 	// read 1st page off disk
-	readseg((uint32_t) ELFHDR, SECTSIZE*8, 0);
+	readseg((uint) ELFHDR, SECTSIZE*8, 0);
 
 	// is this a valid ELF?
 	if (ELFHDR->magic != ELF_MAGIC)
 		goto bad;
 
 	// load each program segment (ignores ph flags)
-	ph = (struct proghdr *) ((uint8_t *) ELFHDR + ELFHDR->phoff);
+	ph = (struct proghdr *) ((uchar *) ELFHDR + ELFHDR->phoff);
 	eph = ph + ELFHDR->phnum;
 	for (; ph < eph; ph++)
 		readseg(ph->va, ph->memsz, ph->offset);
@@ -68,9 +68,9 @@ bad:
 // Read 'count' bytes at 'offset' from kernel into virtual address 'va'.
 // Might copy more than asked
 void
-readseg(uint32_t va, uint32_t count, uint32_t offset)
+readseg(uint va, uint count, uint offset)
 {
-	uint32_t end_va;
+	uint end_va;
 
 	va &= 0xFFFFFF;
 	end_va = va + count;
@@ -85,7 +85,7 @@ readseg(uint32_t va, uint32_t count, uint32_t offset)
 	// We'd write more to memory than asked, but it doesn't matter --
 	// we load in increasing order.
 	while (va < end_va) {
-		readsect((uint8_t*) va, offset);
+		readsect((uchar*) va, offset);
 		va += SECTSIZE;
 		offset++;
 	}
@@ -100,7 +100,7 @@ waitdisk(void)
 }
 
 void
-readsect(void *dst, uint32_t offset)
+readsect(void *dst, uint offset)
 {
 	// wait for disk to be ready
 	waitdisk();
diff --git a/console.c b/console.c
index 5e6e5e1..9756c84 100644
--- a/console.c
+++ b/console.c
@@ -28,7 +28,7 @@ static void
 cons_putc(int c)
 {
   int crtport = 0x3d4; // io port of CGA
-  uint16_t *crt = (uint16_t *) 0xB8000; // base of CGA memory
+  ushort *crt = (ushort *) 0xB8000; // base of CGA memory
   int ind;
 
   if(panicked){
diff --git a/defs.h b/defs.h
index f9c64d3..beed68a 100644
--- a/defs.h
+++ b/defs.h
@@ -40,8 +40,8 @@ int strncmp(const char *p, const char *q, uint n);
 void syscall(void);
 
 // picirq.c
-extern uint16_t irq_mask_8259A;
-void irq_setmask_8259A(uint16_t mask);
+extern ushort irq_mask_8259A;
+void irq_setmask_8259A(ushort mask);
 void pic_init(void);
 
 // mp.c
@@ -50,9 +50,9 @@ void mp_startthem(void);
 int mp_bcpu(void);
 
 // lapic
-extern uint32_t *lapicaddr;
+extern uint *lapicaddr;
 void lapic_init(int);
-void lapic_startap(uint8_t, int);
+void lapic_startap(uchar, int);
 void lapic_timerinit(void);
 void lapic_timerintr(void);
 void lapic_enableintr(void);
@@ -66,7 +66,7 @@ void release(struct spinlock*);
 int holding(struct spinlock*);
 
 // main.c
-void load_icode(struct proc *p, uint8_t *binary, uint size);
+void load_icode(struct proc *p, uchar *binary, uint size);
 
 // pipe.c
 struct pipe;
@@ -87,6 +87,6 @@ void fd_incref(struct fd *fd);
 // ide.c
 void ide_init(void);
 void ide_intr(void);
-void* ide_start_read(uint32_t secno, void *dst, uint nsecs);
+void* ide_start_read(uint secno, void *dst, uint nsecs);
 int ide_finish_read(void *);
 
diff --git a/elf.h b/elf.h
index 807c151..8eb4074 100644
--- a/elf.h
+++ b/elf.h
@@ -1,32 +1,32 @@
 #define ELF_MAGIC 0x464C457FU	/* "\x7FELF" in little endian */
 
 struct elfhdr {
-	uint32_t magic;	// must equal ELF_MAGIC
-	uint8_t elf[12];
-	uint16_t type;
-	uint16_t machine;
-	uint32_t version;
-	uint32_t entry;
-	uint32_t phoff;
-	uint32_t shoff;
-	uint32_t flags;
-	uint16_t ehsize;
-	uint16_t phentsize;
-	uint16_t phnum;
-	uint16_t shentsize;
-	uint16_t shnum;
-	uint16_t shstrndx;
+	uint magic;	// must equal ELF_MAGIC
+	uchar elf[12];
+	ushort type;
+	ushort machine;
+	uint version;
+	uint entry;
+	uint phoff;
+	uint shoff;
+	uint flags;
+	ushort ehsize;
+	ushort phentsize;
+	ushort phnum;
+	ushort shentsize;
+	ushort shnum;
+	ushort shstrndx;
 };
 
 struct proghdr {
-	uint32_t type;
-	uint32_t offset;
-	uint32_t va;
-	uint32_t pa;
-	uint32_t filesz;
-	uint32_t memsz;
-	uint32_t flags;
-	uint32_t align;
+	uint type;
+	uint offset;
+	uint va;
+	uint pa;
+	uint filesz;
+	uint memsz;
+	uint flags;
+	uint align;
 };
 
 // Values for Proghdr type
diff --git a/ide.c b/ide.c
index 2ea2253..5b75053 100644
--- a/ide.c
+++ b/ide.c
@@ -18,7 +18,8 @@
 #define IDE_ERR		0x01
 
 struct ide_request {
-  uint32_t secno;
+  int diskno;
+  uint secno;
   void *dst;
   uint nsecs;
 };
@@ -26,7 +27,6 @@ struct ide_request request[NREQUEST];
 int head, tail;
 struct spinlock ide_lock;
 
-static int diskno = 0;
 int disk_channel;
 
 static int
@@ -79,14 +79,6 @@ ide_probe_disk1(void)
   return (x < 1000);
 }
 
-void
-ide_set_disk(int d)
-{
-  if (d != 0 && d != 1)
-    panic("bad disk number");
-  diskno = d;
-}
-
 void
 ide_start_request (void)
 {
@@ -100,13 +92,13 @@ ide_start_request (void)
     outb(0x1F3, r->secno & 0xFF);
     outb(0x1F4, (r->secno >> 8) & 0xFF);
     outb(0x1F5, (r->secno >> 16) & 0xFF);
-    outb(0x1F6, 0xE0 | ((diskno&1)<<4) | ((r->secno>>24)&0x0F));
+    outb(0x1F6, 0xE0 | ((r->diskno&1)<<4) | ((r->secno>>24)&0x0F));
     outb(0x1F7, 0x20);	// CMD 0x20 means read sector
   }
 }
 
 void *
-ide_start_read(uint32_t secno, void *dst, uint nsecs)
+ide_start_read(uint secno, void *dst, uint nsecs)
 {
   struct ide_request *r;
   if(!holding(&ide_lock))
@@ -122,6 +114,7 @@ ide_start_read(uint32_t secno, void *dst, uint nsecs)
   r->secno = secno;
   r->dst = dst;
   r->nsecs = nsecs;
+  r->diskno = 0;
 
   ide_start_request();
 
@@ -155,9 +148,10 @@ ide_finish_read(void *c)
 }
 
 int
-ide_write(uint32_t secno, const void *src, uint nsecs)
+ide_write(uint secno, const void *src, uint nsecs)
 {
   int r;
+  int diskno = 0;
 	
   if(nsecs > 256)
     panic("ide_write");
diff --git a/lapic.c b/lapic.c
index 5e164be..3aeda2f 100644
--- a/lapic.c
+++ b/lapic.c
@@ -92,7 +92,7 @@ enum {					/* LAPIC_TDCR */
   LAPIC_X1 = 0x0000000B,	/* divide by 1 */
 };
 
-uint32_t *lapicaddr;
+uint *lapicaddr;
 
 static int
 lapic_read(int r)
@@ -127,7 +127,7 @@ lapic_timerintr(void)
 void
 lapic_init(int c)
 {
-  uint32_t r, lvt;
+  uint r, lvt;
 
   cprintf("lapic_init %d\n", c);
 
@@ -180,7 +180,7 @@ cpu(void)
 }
 
 void
-lapic_startap(uint8_t apicid, int v)
+lapic_startap(uchar apicid, int v)
 {
   int crhi, i;
   volatile int j = 0;
diff --git a/main.c b/main.c
index 0cde11e..8a86908 100644
--- a/main.c
+++ b/main.c
@@ -11,9 +11,9 @@
 #include "spinlock.h"
 
 extern char edata[], end[];
-extern uint8_t _binary_user1_start[], _binary_user1_size[];
-extern uint8_t _binary_usertests_start[], _binary_usertests_size[];
-extern uint8_t _binary_userfs_start[], _binary_userfs_size[];
+extern uchar _binary_user1_start[], _binary_user1_size[];
+extern uchar _binary_usertests_start[], _binary_usertests_size[];
+extern uchar _binary_userfs_start[], _binary_userfs_size[];
 
 extern int use_console_lock;
 
@@ -73,7 +73,7 @@ main0(void)
   lapic_enableintr();
 
   // init disk device
-  //ide_init(); 
+  ide_init(); 
 
   // Enable interrupts on this processor.
   cpus[cpu()].nlock--;
@@ -81,8 +81,8 @@ main0(void)
 
   p = copyproc(&proc[0]);
   
-  load_icode(p, _binary_usertests_start, (uint) _binary_usertests_size);
-  //load_icode(p, _binary_userfs_start, (uint) _binary_userfs_size);
+  //load_icode(p, _binary_usertests_start, (uint) _binary_usertests_size);
+  load_icode(p, _binary_userfs_start, (uint) _binary_userfs_size);
   p->state = RUNNABLE;
   cprintf("loaded userfs\n");
 
@@ -107,7 +107,7 @@ mpmain(void)
 }
 
 void
-load_icode(struct proc *p, uint8_t *binary, uint size)
+load_icode(struct proc *p, uchar *binary, uint size)
 {
   int i;
   struct elfhdr *elf;
diff --git a/mmu.h b/mmu.h
index 9dd3aa1..fd10ed6 100644
--- a/mmu.h
+++ b/mmu.h
@@ -124,43 +124,43 @@ struct segdesc {
 
 // Task state segment format (as described by the Pentium architecture book)
 struct taskstate {
-	uint32_t link;	// Old ts selector
-	uintptr_t esp0;	// Stack pointers and segment selectors
-	uint16_t ss0;	//   after an increase in privilege level
-	uint16_t padding1;
-	uintptr_t esp1;
-	uint16_t ss1;
-	uint16_t padding2;
-	uintptr_t esp2;
-	uint16_t ss2;
-	uint16_t padding3;
-	physaddr_t cr3;	// Page directory base
-	uintptr_t eip;	// Saved state from last task switch
-	uint32_t eflags;
-	uint32_t eax;	// More saved state (registers)
-	uint32_t ecx;
-	uint32_t edx;
-	uint32_t ebx;
-	uintptr_t esp;
-	uintptr_t ebp;
-	uint32_t esi;
-	uint32_t edi;
-	uint16_t es;		// Even more saved state (segment selectors)
-	uint16_t padding4;
-	uint16_t cs;
-	uint16_t padding5;
-	uint16_t ss;
-	uint16_t padding6;
-	uint16_t ds;
-	uint16_t padding7;
-	uint16_t fs;
-	uint16_t padding8;
-	uint16_t gs;
-	uint16_t padding9;
-	uint16_t ldt;
-	uint16_t padding10;
-	uint16_t t;		// Trap on task switch
-	uint16_t iomb;	// I/O map base address
+	uint link;	// Old ts selector
+	uint * esp0;	// Stack pointers and segment selectors
+	ushort ss0;	//   after an increase in privilege level
+	ushort padding1;
+	uint * esp1;
+	ushort ss1;
+	ushort padding2;
+	uint * esp2;
+	ushort ss2;
+	ushort padding3;
+	void * cr3;	// Page directory base
+	uint * eip;	// Saved state from last task switch
+	uint eflags;
+	uint eax;	// More saved state (registers)
+	uint ecx;
+	uint edx;
+	uint ebx;
+	uint * esp;
+	uint * ebp;
+	uint esi;
+	uint edi;
+	ushort es;		// Even more saved state (segment selectors)
+	ushort padding4;
+	ushort cs;
+	ushort padding5;
+	ushort ss;
+	ushort padding6;
+	ushort ds;
+	ushort padding7;
+	ushort fs;
+	ushort padding8;
+	ushort gs;
+	ushort padding9;
+	ushort ldt;
+	ushort padding10;
+	ushort t;		// Trap on task switch
+	ushort iomb;	// I/O map base address
 };
 
 // Gate descriptors for interrupts and traps
@@ -185,7 +185,7 @@ struct gatedesc {
 //	  this interrupt/trap gate explicitly using an int instruction.
 #define SETGATE(gate, istrap, sel, off, d)			\
 {								\
-	(gate).off_15_0 = (uint32_t) (off) & 0xffff;		\
+	(gate).off_15_0 = (uint) (off) & 0xffff;		\
 	(gate).ss = (sel);					\
 	(gate).args = 0;					\
 	(gate).rsv1 = 0;					\
@@ -193,13 +193,13 @@ struct gatedesc {
 	(gate).s = 0;					\
 	(gate).dpl = (d);					\
 	(gate).p = 1;					\
-	(gate).off_31_16 = (uint32_t) (off) >> 16;		\
+	(gate).off_31_16 = (uint) (off) >> 16;		\
 }
 
 // Set up a call gate descriptor.
 #define SETCALLGATE(gate, ss, off, d)           	        \
 {								\
-	(gate).off_15_0 = (uint32_t) (off) & 0xffff;		\
+	(gate).off_15_0 = (uint) (off) & 0xffff;		\
 	(gate).ss = (ss);					\
 	(gate).args = 0;					\
 	(gate).rsv1 = 0;					\
@@ -207,7 +207,7 @@ struct gatedesc {
 	(gate).s = 0;					\
 	(gate).dpl = (d);					\
 	(gate).p = 1;					\
-	(gate).off_31_16 = (uint32_t) (off) >> 16;		\
+	(gate).off_31_16 = (uint) (off) >> 16;		\
 }
 
 #endif /* !__ASSEMBLER__ */
diff --git a/mp.c b/mp.c
index b41cdf3..4cb5db8 100644
--- a/mp.c
+++ b/mp.c
@@ -37,12 +37,12 @@ int ncpu;
 static struct cpu *bcpu;
 
 static struct mp*
-mp_scan(uint8_t *addr, int len)
+mp_scan(uchar *addr, int len)
 {
-  uint8_t *e, *p, sum;
+  uchar *e, *p, sum;
   int i;
 
-  cprintf("scanning: 0x%x\n", (uint32_t)addr);
+  cprintf("scanning: 0x%x\n", (uint)addr);
   e = addr+len;
   for(p = addr; p < e; p += sizeof(struct mp)){
     if(memcmp(p, "_MP_", 4))
@@ -59,8 +59,8 @@ mp_scan(uint8_t *addr, int len)
 static struct mp*
 mp_search(void)
 {
-  uint8_t *bda;
-  uint32_t p;
+  uchar *bda;
+  uint p;
   struct mp *mp;
 
   /*
@@ -70,25 +70,25 @@ mp_search(void)
    * 2) in the last KB of system base memory;
    * 3) in the BIOS ROM between 0xE0000 and 0xFFFFF.
    */
-  bda = (uint8_t*) 0x400;
+  bda = (uchar*) 0x400;
   if((p = (bda[0x0F]<<8)|bda[0x0E])){
-    if((mp = mp_scan((uint8_t*) p, 1024)))
+    if((mp = mp_scan((uchar*) p, 1024)))
       return mp;
   }
   else{
     p = ((bda[0x14]<<8)|bda[0x13])*1024;
-    if((mp = mp_scan((uint8_t*)p-1024, 1024)))
+    if((mp = mp_scan((uchar*)p-1024, 1024)))
       return mp;
   }
-  return mp_scan((uint8_t*)0xF0000, 0x10000);
+  return mp_scan((uchar*)0xF0000, 0x10000);
 }
 
 static int 
 mp_detect(void)
 {
   struct mpctb *pcmp;
-  uint8_t *p, sum;
-  uint32_t length;
+  uchar *p, sum;
+  uint length;
 
   /*
    * Search for an MP configuration table. For now,
@@ -106,7 +106,7 @@ mp_detect(void)
 
   length = pcmp->length;
   sum = 0;
-  for(p = (uint8_t*)pcmp; length; length--)
+  for(p = (uchar*)pcmp; length; length--)
     sum += *p++;
 
   if(sum || (pcmp->version != 1 && pcmp->version != 4))
@@ -120,7 +120,7 @@ void
 mp_init(void)
 { 
   int r;
-  uint8_t *p, *e;
+  uchar *p, *e;
   struct mpctb *mpctb;
   struct mppe *proc;
   struct mpbe *bus;
@@ -137,10 +137,10 @@ mp_init(void)
    * is guaranteed to be in order such that only one pass is necessary.
    */
   mpctb = (struct mpctb *) mp->physaddr;
-  lapicaddr = (uint32_t *) mpctb->lapicaddr;
+  lapicaddr = (uint *) mpctb->lapicaddr;
   cprintf("apicaddr: %x\n", lapicaddr);
-  p = ((uint8_t*)mpctb)+sizeof(struct mpctb);
-  e = ((uint8_t*)mpctb)+mpctb->length;
+  p = ((uchar*)mpctb)+sizeof(struct mpctb);
+  e = ((uchar*)mpctb)+mpctb->length;
 
   while(p < e) {
     switch(*p){
@@ -195,18 +195,18 @@ extern void mpmain(void);
 void
 mp_startthem(void)
 {
-  extern uint8_t _binary_bootother_start[], _binary_bootother_size[];
+  extern uchar _binary_bootother_start[], _binary_bootother_size[];
   extern int main();
   int c;
 
   memmove((void *) APBOOTCODE,_binary_bootother_start, 
-	  (uint32_t) _binary_bootother_size);
+	  (uint) _binary_bootother_size);
 
   for(c = 0; c < ncpu; c++){
     if (c == cpu()) continue;
     cprintf ("starting processor %d\n", c);
     *(uint *)(APBOOTCODE-4) = (uint) (cpus[c].mpstack) + MPSTACK; // tell it what to use for %esp
     *(uint *)(APBOOTCODE-8) = (uint)mpmain; // tell it where to jump to
-    lapic_startap(cpus[c].apicid, (uint32_t) APBOOTCODE);
+    lapic_startap(cpus[c].apicid, (uint) APBOOTCODE);
   }
 }
diff --git a/mp.h b/mp.h
index b24aa94..2117b1e 100644
--- a/mp.h
+++ b/mp.h
@@ -5,63 +5,63 @@
  */
 
 struct mp {			/* floating pointer */
-  uint8_t signature[4];		/* "_MP_" */
-  physaddr_t physaddr;	        /* physical address of MP configuration table */
-  uint8_t length;		/* 1 */
-  uint8_t specrev;		/* [14] */
-  uint8_t checksum;		/* all bytes must add up to 0 */
-  uint8_t type;			/* MP system configuration type */
-  uint8_t imcrp;
-  uint8_t reserved[3];
+  uchar signature[4];		/* "_MP_" */
+  void* physaddr;	        /* physical address of MP configuration table */
+  uchar length;		/* 1 */
+  uchar specrev;		/* [14] */
+  uchar checksum;		/* all bytes must add up to 0 */
+  uchar type;			/* MP system configuration type */
+  uchar imcrp;
+  uchar reserved[3];
 };
 
 struct mpctb {			/* configuration table header */
-  uint8_t signature[4];		/* "PCMP" */
-  uint16_t length;		/* total table length */
-  uint8_t version;		/* [14] */
-  uint8_t checksum;		/* all bytes must add up to 0 */
-  uint8_t product[20];		/* product id */
-  uintptr_t oemtable;		/* OEM table pointer */
-  uint16_t oemlength;		/* OEM table length */
-  uint16_t entry;		/* entry count */
-  uintptr_t lapicaddr;		/* address of local APIC */
-  uint16_t xlength;		/* extended table length */
-  uint8_t xchecksum;		/* extended table checksum */
-  uint8_t reserved;
+  uchar signature[4];		/* "PCMP" */
+  ushort length;		/* total table length */
+  uchar version;		/* [14] */
+  uchar checksum;		/* all bytes must add up to 0 */
+  uchar product[20];		/* product id */
+  uint * oemtable;		/* OEM table pointer */
+  ushort oemlength;		/* OEM table length */
+  ushort entry;		/* entry count */
+  uint * lapicaddr;		/* address of local APIC */
+  ushort xlength;		/* extended table length */
+  uchar xchecksum;		/* extended table checksum */
+  uchar reserved;
 };
 
 struct mppe {		/* processor table entry */
-  uint8_t type;			/* entry type (0) */
-  uint8_t apicid;		/* local APIC id */
-  uint8_t version;		/* local APIC verison */
-  uint8_t flags;		/* CPU flags */
-  uint8_t signature[4];		/* CPU signature */
-  uint32_t feature;		/* feature flags from CPUID instruction */
-  uint8_t reserved[8];
+  uchar type;			/* entry type (0) */
+  uchar apicid;		/* local APIC id */
+  uchar version;		/* local APIC verison */
+  uchar flags;		/* CPU flags */
+  uchar signature[4];		/* CPU signature */
+  uint feature;		/* feature flags from CPUID instruction */
+  uchar reserved[8];
 };
 
 struct mpbe {		/* bus table entry */
-  uint8_t type;			/* entry type (1) */
-  uint8_t busno;		/* bus id */
+  uchar type;			/* entry type (1) */
+  uchar busno;		/* bus id */
   char string[6];		/* bus type string */
 };
 
 struct mpioapic {	/* I/O APIC table entry */
-  uint8_t type;			/* entry type (2) */
-  uint8_t apicno;		/* I/O APIC id */
-  uint8_t version;		/* I/O APIC version */
-  uint8_t flags;		/* I/O APIC flags */
-  uintptr_t addr;		/* I/O APIC address */
+  uchar type;			/* entry type (2) */
+  uchar apicno;		/* I/O APIC id */
+  uchar version;		/* I/O APIC version */
+  uchar flags;		/* I/O APIC flags */
+  uint * addr;		/* I/O APIC address */
 };
 
 struct mpie {		/* interrupt table entry */
-  uint8_t type;			/* entry type ([34]) */
-  uint8_t intr;			/* interrupt type */
-  uint16_t flags;		/* interrupt flag */
-  uint8_t busno;		/* source bus id */
-  uint8_t irq;			/* source bus irq */
-  uint8_t apicno;		/* destination APIC id */
-  uint8_t intin;		/* destination APIC [L]INTIN# */
+  uchar type;			/* entry type ([34]) */
+  uchar intr;			/* interrupt type */
+  ushort flags;		/* interrupt flag */
+  uchar busno;		/* source bus id */
+  uchar irq;			/* source bus irq */
+  uchar apicno;		/* destination APIC id */
+  uchar intin;		/* destination APIC [L]INTIN# */
 };
 
 enum {			/* table entry types */
diff --git a/picirq.c b/picirq.c
index 9c3ea0c..9818090 100644
--- a/picirq.c
+++ b/picirq.c
@@ -12,7 +12,7 @@
 
 // Current IRQ mask.
 // Initial IRQ mask has interrupt 2 enabled (for slave 8259A).
-uint16_t irq_mask_8259A = 0xFFFF & ~(1<<IRQ_SLAVE);
+ushort irq_mask_8259A = 0xFFFF & ~(1<<IRQ_SLAVE);
 
 /* Initialize the 8259A interrupt controllers. */
 void
@@ -71,7 +71,7 @@ pic_init(void)
 }
 
 void
-irq_setmask_8259A(uint16_t mask)
+irq_setmask_8259A(ushort mask)
 {
   int i;
   irq_mask_8259A = mask;
diff --git a/proc.h b/proc.h
index 8fb935c..1b86eb2 100644
--- a/proc.h
+++ b/proc.h
@@ -65,7 +65,7 @@ extern struct proc *curproc[NCPU];  // can be NULL if no proc running.
 #define MPSTACK 512
 
 struct cpu {
-  uint8_t apicid;       // Local APIC ID
+  uchar apicid;       // Local APIC ID
   struct jmpbuf jmpbuf;
   char mpstack[MPSTACK]; // per-cpu start-up stack, only used to get into main()
   struct proc *lastproc;  // last proc scheduled on this cpu (never NULL)
diff --git a/spinlock.h b/spinlock.h
index 656d272..0572124 100644
--- a/spinlock.h
+++ b/spinlock.h
@@ -1,5 +1,5 @@
 struct spinlock {
   uint locked;
-  uint32_t pc;
+  uint pc;
   int cpu;
 };
diff --git a/string.c b/string.c
index dbce231..98253ed 100644
--- a/string.c
+++ b/string.c
@@ -15,8 +15,8 @@ memset(void *dst, int c, uint n)
 int
 memcmp(const void *v1, const void *v2, uint n)
 {
-  const uint8_t *s1 = (const uint8_t *) v1;
-  const uint8_t *s2 = (const uint8_t *) v2;
+  const uchar *s1 = (const uchar *) v1;
+  const uchar *s2 = (const uchar *) v2;
 
   while (n-- > 0) {
     if (*s1 != *s2)
@@ -55,7 +55,7 @@ strncmp(const char *p, const char *q, uint n)
 	if (n == 0)
 		return 0;
 	else
-		return (int) ((uint8_t) *p - (uint8_t) *q);
+		return (int) ((uchar) *p - (uchar) *q);
 }
 
 // Memcpy is deprecated and should NOT be called.
diff --git a/syscall.c b/syscall.c
index 3f5e2ba..ff5fea6 100644
--- a/syscall.c
+++ b/syscall.c
@@ -235,8 +235,10 @@ sys_block(void)
     if ((c = ide_start_read(i, buf, 1)) == 0) {
       panic("couldn't start read\n");
     }
+#if 0
     cprintf("call sleep\n");
     sleep (c, &ide_lock);
+#endif
     if (ide_finish_read(c)) {
       panic("couldn't do read\n");
     }
diff --git a/types.h b/types.h
index 938154b..8c54fd8 100644
--- a/types.h
+++ b/types.h
@@ -1,9 +1,3 @@
-typedef unsigned int       uint;
-
-typedef unsigned long long uint64_t;
-typedef unsigned int       uint32_t;
-typedef unsigned short     uint16_t;
-typedef unsigned char      uint8_t;
-
-typedef uint32_t           uintptr_t;
-typedef uint32_t           physaddr_t;
+typedef unsigned int uint;
+typedef unsigned short ushort;
+typedef unsigned char uchar;
diff --git a/x86.h b/x86.h
index 444c6df..41a6e9a 100644
--- a/x86.h
+++ b/x86.h
@@ -1,37 +1,36 @@
 static __inline void breakpoint(void) __attribute__((always_inline));
-static __inline uint8_t inb(int port) __attribute__((always_inline));
+static __inline uchar inb(int port) __attribute__((always_inline));
 static __inline void insb(int port, void *addr, int cnt) __attribute__((always_inline));
-static __inline uint16_t inw(int port) __attribute__((always_inline));
+static __inline ushort inw(int port) __attribute__((always_inline));
 static __inline void insw(int port, void *addr, int cnt) __attribute__((always_inline));
-static __inline uint32_t inl(int port) __attribute__((always_inline));
+static __inline uint inl(int port) __attribute__((always_inline));
 static __inline void insl(int port, void *addr, int cnt) __attribute__((always_inline));
-static __inline void outb(int port, uint8_t data) __attribute__((always_inline));
+static __inline void outb(int port, uchar data) __attribute__((always_inline));
 static __inline void outsb(int port, const void *addr, int cnt) __attribute__((always_inline));
-static __inline void outw(int port, uint16_t data) __attribute__((always_inline));
+static __inline void outw(int port, ushort data) __attribute__((always_inline));
 static __inline void outsw(int port, const void *addr, int cnt) __attribute__((always_inline));
 static __inline void outsl(int port, const void *addr, int cnt) __attribute__((always_inline));
-static __inline void outl(int port, uint32_t data) __attribute__((always_inline));
+static __inline void outl(int port, uint data) __attribute__((always_inline));
 static __inline void invlpg(void *addr) __attribute__((always_inline));
 struct segdesc;
 static __inline void lgdt(struct segdesc *p, int) __attribute__((always_inline));
 struct gatedesc;
 static __inline void lidt(struct gatedesc *p, int) __attribute__((always_inline));
-static __inline void lldt(uint16_t sel) __attribute__((always_inline));
-static __inline void ltr(uint16_t sel) __attribute__((always_inline));
-static __inline void lcr0(uint32_t val) __attribute__((always_inline));
-static __inline uint32_t rcr0(void) __attribute__((always_inline));
-static __inline uint32_t rcr2(void) __attribute__((always_inline));
-static __inline void lcr3(uint32_t val) __attribute__((always_inline));
-static __inline uint32_t rcr3(void) __attribute__((always_inline));
-static __inline void lcr4(uint32_t val) __attribute__((always_inline));
-static __inline uint32_t rcr4(void) __attribute__((always_inline));
+static __inline void lldt(ushort sel) __attribute__((always_inline));
+static __inline void ltr(ushort sel) __attribute__((always_inline));
+static __inline void lcr0(uint val) __attribute__((always_inline));
+static __inline uint rcr0(void) __attribute__((always_inline));
+static __inline uint rcr2(void) __attribute__((always_inline));
+static __inline void lcr3(uint val) __attribute__((always_inline));
+static __inline uint rcr3(void) __attribute__((always_inline));
+static __inline void lcr4(uint val) __attribute__((always_inline));
+static __inline uint rcr4(void) __attribute__((always_inline));
 static __inline void tlbflush(void) __attribute__((always_inline));
-static __inline uint32_t read_eflags(void) __attribute__((always_inline));
-static __inline void write_eflags(uint32_t eflags) __attribute__((always_inline));
-static __inline uint32_t read_ebp(void) __attribute__((always_inline));
-static __inline uint32_t read_esp(void) __attribute__((always_inline));
-static __inline void cpuid(uint32_t info, uint32_t *eaxp, uint32_t *ebxp, uint32_t *ecxp, uint32_t *edxp);
-static __inline uint64_t read_tsc(void) __attribute__((always_inline));
+static __inline uint read_eflags(void) __attribute__((always_inline));
+static __inline void write_eflags(uint eflags) __attribute__((always_inline));
+static __inline uint read_ebp(void) __attribute__((always_inline));
+static __inline uint read_esp(void) __attribute__((always_inline));
+static __inline void cpuid(uint info, uint *eaxp, uint *ebxp, uint *ecxp, uint *edxp);
 static __inline void cli(void) __attribute__((always_inline));
 static __inline void sti(void) __attribute__((always_inline));
 
@@ -41,10 +40,10 @@ breakpoint(void)
 	__asm __volatile("int3");
 }
 
-static __inline uint8_t
+static __inline uchar
 inb(int port)
 {
-	uint8_t data;
+	uchar data;
 	__asm __volatile("inb %w1,%0" : "=a" (data) : "d" (port));
 	return data;
 }
@@ -58,10 +57,10 @@ insb(int port, void *addr, int cnt)
 			 "memory", "cc");
 }
 
-static __inline uint16_t
+static __inline ushort
 inw(int port)
 {
-	uint16_t data;
+	ushort data;
 	__asm __volatile("inw %w1,%0" : "=a" (data) : "d" (port));
 	return data;
 }
@@ -75,10 +74,10 @@ insw(int port, void *addr, int cnt)
 			 "memory", "cc");
 }
 
-static __inline uint32_t
+static __inline uint
 inl(int port)
 {
-	uint32_t data;
+	uint data;
 	__asm __volatile("inl %w1,%0" : "=a" (data) : "d" (port));
 	return data;
 }
@@ -93,7 +92,7 @@ insl(int port, void *addr, int cnt)
 }
 
 static __inline void
-outb(int port, uint8_t data)
+outb(int port, uchar data)
 {
 	__asm __volatile("outb %0,%w1" : : "a" (data), "d" (port));
 }
@@ -108,7 +107,7 @@ outsb(int port, const void *addr, int cnt)
 }
 
 static __inline void
-outw(int port, uint16_t data)
+outw(int port, ushort data)
 {
 	__asm __volatile("outw %0,%w1" : : "a" (data), "d" (port));
 }
@@ -132,7 +131,7 @@ outsl(int port, const void *addr, int cnt)
 }
 
 static __inline void
-outl(int port, uint32_t data)
+outl(int port, uint data)
 {
 	__asm __volatile("outl %0,%w1" : : "a" (data), "d" (port));
 }
@@ -146,7 +145,7 @@ invlpg(void *addr)
 static __inline void
 lgdt(struct segdesc *p, int size)
 {
-	volatile uint16_t pd[3];
+	volatile ushort pd[3];
   
 	pd[0] = size-1;
 	pd[1] = (uint)p;
@@ -158,7 +157,7 @@ lgdt(struct segdesc *p, int size)
 static __inline void
 lidt(struct gatedesc *p, int size)
 {
-	volatile uint16_t pd[3];
+	volatile ushort pd[3];
   
 	pd[0] = size-1;
 	pd[1] = (uint)p;
@@ -168,63 +167,63 @@ lidt(struct gatedesc *p, int size)
 }
 
 static __inline void
-lldt(uint16_t sel)
+lldt(ushort sel)
 {
 	__asm __volatile("lldt %0" : : "r" (sel));
 }
 
 static __inline void
-ltr(uint16_t sel)
+ltr(ushort sel)
 {
 	__asm __volatile("ltr %0" : : "r" (sel));
 }
 
 static __inline void
-lcr0(uint32_t val)
+lcr0(uint val)
 {
 	__asm __volatile("movl %0,%%cr0" : : "r" (val));
 }
 
-static __inline uint32_t
+static __inline uint
 rcr0(void)
 {
-	uint32_t val;
+	uint val;
 	__asm __volatile("movl %%cr0,%0" : "=r" (val));
 	return val;
 }
 
-static __inline uint32_t
+static __inline uint
 rcr2(void)
 {
-	uint32_t val;
+	uint val;
 	__asm __volatile("movl %%cr2,%0" : "=r" (val));
 	return val;
 }
 
 static __inline void
-lcr3(uint32_t val)
+lcr3(uint val)
 {
 	__asm __volatile("movl %0,%%cr3" : : "r" (val));
 }
 
-static __inline uint32_t
+static __inline uint
 rcr3(void)
 {
-	uint32_t val;
+	uint val;
 	__asm __volatile("movl %%cr3,%0" : "=r" (val));
 	return val;
 }
 
 static __inline void
-lcr4(uint32_t val)
+lcr4(uint val)
 {
 	__asm __volatile("movl %0,%%cr4" : : "r" (val));
 }
 
-static __inline uint32_t
+static __inline uint
 rcr4(void)
 {
-	uint32_t cr4;
+	uint cr4;
 	__asm __volatile("movl %%cr4,%0" : "=r" (cr4));
 	return cr4;
 }
@@ -232,69 +231,69 @@ rcr4(void)
 static __inline void
 tlbflush(void)
 {
-	uint32_t cr3;
+	uint cr3;
 	__asm __volatile("movl %%cr3,%0" : "=r" (cr3));
 	__asm __volatile("movl %0,%%cr3" : : "r" (cr3));
 }
 
-static __inline uint32_t
+static __inline uint
 read_eflags(void)
 {
-        uint32_t eflags;
+        uint eflags;
         __asm __volatile("pushfl; popl %0" : "=r" (eflags));
         return eflags;
 }
 
 static __inline void
-write_eflags(uint32_t eflags)
+write_eflags(uint eflags)
 {
         __asm __volatile("pushl %0; popfl" : : "r" (eflags));
 }
 
-static __inline uint32_t
+static __inline uint
 read_ebp(void)
 {
-        uint32_t ebp;
+        uint ebp;
         __asm __volatile("movl %%ebp,%0" : "=r" (ebp));
         return ebp;
 }
 
-static __inline uint32_t
+static __inline uint
 read_esp(void)
 {
-        uint32_t esp;
+        uint esp;
         __asm __volatile("movl %%esp,%0" : "=r" (esp));
         return esp;
 }
 
-static __inline uint32_t
+static __inline uint
 read_esi(void)
 {
-        uint32_t esi;
+        uint esi;
         __asm __volatile("movl %%esi,%0" : "=r" (esi));
         return esi;
 }
 
-static __inline uint32_t
+static __inline uint
 read_edi(void)
 {
-        uint32_t edi;
+        uint edi;
         __asm __volatile("movl %%edi,%0" : "=r" (edi));
         return edi;
 }
 
-static __inline uint32_t
+static __inline uint
 read_ebx(void)
 {
-        uint32_t ebx;
+        uint ebx;
         __asm __volatile("movl %%ebx,%0" : "=r" (ebx));
         return ebx;
 }
 
 static __inline void
-cpuid(uint32_t info, uint32_t *eaxp, uint32_t *ebxp, uint32_t *ecxp, uint32_t *edxp)
+cpuid(uint info, uint *eaxp, uint *ebxp, uint *ecxp, uint *edxp)
 {
-	uint32_t eax, ebx, ecx, edx;
+	uint eax, ebx, ecx, edx;
 	asm volatile("cpuid" 
 		: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
 		: "a" (info));
@@ -308,10 +307,10 @@ cpuid(uint32_t info, uint32_t *eaxp, uint32_t *ebxp, uint32_t *ecxp, uint32_t *e
 		*edxp = edx;
 }
 
-static __inline uint32_t
-cmpxchg(uint32_t oldval, uint32_t newval, volatile uint32_t* lock_addr)
+static __inline uint
+cmpxchg(uint oldval, uint newval, volatile uint* lock_addr)
 {
-  uint32_t result;
+  uint result;
   __asm__ __volatile__(
 		       "lock; cmpxchgl %2, %0"
 		       :"+m" (*lock_addr), "=a" (result) : "r"(newval), "1"(oldval) : "cc"
@@ -319,14 +318,6 @@ cmpxchg(uint32_t oldval, uint32_t newval, volatile uint32_t* lock_addr)
   return result;
 }
 
-static __inline uint64_t
-read_tsc(void)
-{
-        uint64_t tsc;
-        __asm __volatile("rdtsc" : "=A" (tsc));
-        return tsc;
-}
-
 static __inline void
 cli(void)
 {
@@ -341,30 +332,30 @@ sti(void)
 
 struct trapframe {
     /* registers as pushed by pusha */
-    uint32_t edi;
-    uint32_t esi;
-    uint32_t ebp;
-    uint32_t oesp;      /* Useless */
-    uint32_t ebx;
-    uint32_t edx;
-    uint32_t ecx;
-    uint32_t eax;
+    uint edi;
+    uint esi;
+    uint ebp;
+    uint oesp;      /* Useless */
+    uint ebx;
+    uint edx;
+    uint ecx;
+    uint eax;
     /* rest of trap frame */
-    uint16_t es;
-    uint16_t padding1;
-    uint16_t ds;
-    uint16_t padding2;
-    uint32_t trapno;
+    ushort es;
+    ushort padding1;
+    ushort ds;
+    ushort padding2;
+    uint trapno;
     /* below here defined by x86 hardware */
-    uint32_t err;
-    uintptr_t eip;
-    uint16_t cs;
-    uint16_t padding3;
-    uint32_t eflags;
+    uint err;
+    uint eip;
+    ushort cs;
+    ushort padding3;
+    uint eflags;
     /* below here only when crossing rings, such as from user to kernel */
-    uintptr_t esp;
-    uint16_t ss;
-    uint16_t padding4;
+    uint esp;
+    ushort ss;
+    ushort padding4;
 };
 
 #define MAX_IRQS	16	// Number of IRQs