Added formatting, made syscall.rs clearer to read.

risc_v/src/minixfs.rs

@@ -228,7 +228,11 @@ impl FileSystem for MinixFileSystem {
 				// Once again, here we actually copy the bytes into the final destination, the buffer. This memcpy
 				// is written in cpu.rs.
 				unsafe {
-					memcpy(buffer.add(bytes_read as usize), block_buffer.get().add(offset_byte as usize), read_this_many as usize);
+					memcpy(
+					       buffer.add(bytes_read as usize,),
+					       block_buffer.get().add(offset_byte as usize,),
+					       read_this_many as usize,
+					);
 				}
 				// Regardless of whether we have an offset or not, we reset the offset byte back to 0. This
 				// probably will get set to 0 many times, but who cares?
@@ -261,14 +265,23 @@ impl FileSystem for MinixFileSystem {
 				unsafe {
 					if izones.add(i).read() != 0 {
 						if offset_block <= blocks_seen {
-							syc_read(desc, block_buffer.get_mut(), BLOCK_SIZE, BLOCK_SIZE * izones.add(i).read());
+							syc_read(
+							         desc,
+							         block_buffer.get_mut(),
+							         BLOCK_SIZE,
+							         BLOCK_SIZE * izones.add(i,).read(),
+							);
 							let read_this_many = if BLOCK_SIZE - offset_byte > bytes_left {
 								bytes_left
 							}
 							else {
 								BLOCK_SIZE - offset_byte
 							};
-							memcpy(buffer.add(bytes_read as usize), block_buffer.get().add(offset_byte as usize), read_this_many as usize);
+							memcpy(
+							       buffer.add(bytes_read as usize,),
+							       block_buffer.get().add(offset_byte as usize,),
+							       read_this_many as usize,
+							);
 							bytes_read += read_this_many;
 							bytes_left -= read_this_many;
 							offset_byte = 0;
@@ -297,7 +310,12 @@ impl FileSystem for MinixFileSystem {
 						for j in 0..num_indirect_pointers {
 							if iizones.add(j).read() != 0 {
 								if offset_block <= blocks_seen {
-									syc_read(desc, block_buffer.get_mut(), BLOCK_SIZE, BLOCK_SIZE * iizones.add(j).read());
+									syc_read(
+									         desc,
+									         block_buffer.get_mut(),
+									         BLOCK_SIZE,
+									         BLOCK_SIZE * iizones.add(j,).read(),
+									);
 									let read_this_many = if BLOCK_SIZE - offset_byte > bytes_left {
 										bytes_left
 									}
@@ -340,12 +358,23 @@ impl FileSystem for MinixFileSystem {
 						syc_read(desc, iindirect_buffer.get_mut(), BLOCK_SIZE, BLOCK_SIZE * izones.add(i).read());
 						for j in 0..num_indirect_pointers {
 							if iizones.add(j).read() != 0 {
-								syc_read(desc, iiindirect_buffer.get_mut(), BLOCK_SIZE, BLOCK_SIZE * iizones.add(j).read());
+								syc_read(
+								         desc,
+								         iiindirect_buffer.get_mut(),
+								         BLOCK_SIZE,
+								         BLOCK_SIZE * iizones.add(j,).read(),
+								);
 								for k in 0..num_indirect_pointers {
 									if iiizones.add(k).read() != 0 {
 										if offset_block <= blocks_seen {
-											syc_read(desc, block_buffer.get_mut(), BLOCK_SIZE, BLOCK_SIZE * iiizones.add(k).read());
+											syc_read(
-											let read_this_many = if BLOCK_SIZE - offset_byte > bytes_left {
+											         desc,
+											         block_buffer.get_mut(),
+											         BLOCK_SIZE,
+											         BLOCK_SIZE * iiizones.add(k,).read(),
+											);
+											let read_this_many =
+												if BLOCK_SIZE - offset_byte > bytes_left {
 													bytes_left
 												}
 												else {
@@ -353,7 +382,8 @@ impl FileSystem for MinixFileSystem {
 												};
 											memcpy(
 											       buffer.add(bytes_read as usize,),
-											       block_buffer.get().add(offset_byte as usize,),
+											       block_buffer.get()
+											                   .add(offset_byte as usize,),
 											       read_this_many as usize,
 											);
 											bytes_read += read_this_many;

risc_v/src/syscall.rs

@@ -4,7 +4,7 @@
 // 3 Jan 2020
 
 use crate::{block::block_op,
-            cpu::{TrapFrame, dump_registers},
+            cpu::{dump_registers, TrapFrame},
             minixfs,
             page::{virt_to_phys, Table},
             process::{delete_process, get_by_pid, set_sleeping, set_waiting}};
@@ -13,13 +13,14 @@ use crate::{block::block_op,
 /// made here whether this is a U-mode, S-mode, or M-mode system call.
 /// Since we can't do anything unless we dereference the passed pointer,
 /// I went ahead and made the entire function unsafe.
+/// If we return 0 from this function, the m_trap function will schedule
+/// the next process--consider this a yield. A non-0 is the program counter
+/// we want to go back to.
 pub unsafe fn do_syscall(mepc: usize, frame: *mut TrapFrame) -> usize {
-	let syscall_number;
 	// Libgloss expects the system call number in A7, so let's follow
 	// their lead.
 	// A7 is X17, so it's register number 17.
-	syscall_number = (*frame).regs[17];
+	let syscall_number = (*frame).regs[17];
-
 	match syscall_number {
 		0 | 93 => {
 			// Exit
@@ -84,7 +85,14 @@ pub unsafe fn do_syscall(mepc: usize, frame: *mut TrapFrame) -> usize {
 			//          (*frame).regs[13]
 			// );
 			set_waiting((*frame).pid as u16);
-			let _ = block_op((*frame).regs[10], (*frame).regs[11] as *mut u8, (*frame).regs[12] as u32, (*frame).regs[13] as u64, false, (*frame).pid as u16);
+			let _ = block_op(
+			                 (*frame).regs[10],
+			                 (*frame).regs[11] as *mut u8,
+			                 (*frame).regs[12] as u32,
+			                 (*frame).regs[13] as u64,
+			                 false,
+			                 (*frame).pid as u16,
+			);
 			0
 		},
 		_ => {