feat: init Lab5

woai3c · Feb 27, 2020 · e6b3fab · e6b3fab
1 parent 289a520
commit e6b3fab
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Showing 71 changed files with 4,738 additions and 21 deletions.
diff --git a/GNUmakefile b/GNUmakefile
@@ -141,6 +141,7 @@ include boot/Makefrag
 include kern/Makefrag
 include lib/Makefrag
 include user/Makefrag
+include fs/Makefrag
 
 
 CPUS ?= 1
@@ -149,6 +150,8 @@ QEMUOPTS = -drive file=$(OBJDIR)/kern/kernel.img,index=0,media=disk,format=raw -
 QEMUOPTS += $(shell if $(QEMU) -nographic -help | grep -q '^-D '; then echo '-D qemu.log'; fi)
 IMAGES = $(OBJDIR)/kern/kernel.img
 QEMUOPTS += -smp $(CPUS)
+QEMUOPTS += -drive file=$(OBJDIR)/fs/fs.img,index=1,media=disk,format=raw
+IMAGES += $(OBJDIR)/fs/fs.img
 QEMUOPTS += $(QEMUEXTRA)
 
 .gdbinit: .gdbinit.tmpl

diff --git a/conf/lab.mk b/conf/lab.mk
@@ -1,2 +1,2 @@
-LAB=4
-PACKAGEDATE=Mon Oct 8 21:31:51 PDT 2018
+LAB=5
+PACKAGEDATE=Wed Oct 24 20:44:37 EDT 2018
diff --git a/fs/Makefrag b/fs/Makefrag
@@ -0,0 +1,77 @@
+
+OBJDIRS += fs
+
+FSOFILES := 		$(OBJDIR)/fs/ide.o \
+			$(OBJDIR)/fs/bc.o \
+			$(OBJDIR)/fs/fs.o \
+			$(OBJDIR)/fs/serv.o \
+			$(OBJDIR)/fs/test.o \
+
+USERAPPS := 		$(OBJDIR)/user/init
+
+FSIMGTXTFILES :=	fs/newmotd \
+			fs/motd
+
+
+USERAPPS :=		$(USERAPPS) \
+			$(OBJDIR)/user/cat \
+			$(OBJDIR)/user/echo \
+			$(OBJDIR)/user/init \
+			$(OBJDIR)/user/ls \
+			$(OBJDIR)/user/lsfd \
+			$(OBJDIR)/user/num \
+			$(OBJDIR)/user/forktree \
+			$(OBJDIR)/user/primes \
+			$(OBJDIR)/user/primespipe \
+			$(OBJDIR)/user/sh \
+			$(OBJDIR)/user/testfdsharing \
+			$(OBJDIR)/user/testkbd \
+			$(OBJDIR)/user/testpipe \
+			$(OBJDIR)/user/testpteshare \
+			$(OBJDIR)/user/testshell \
+			$(OBJDIR)/user/hello \
+			$(OBJDIR)/user/faultio \
+
+FSIMGTXTFILES :=	$(FSIMGTXTFILES) \
+			fs/lorem \
+			fs/script \
+			fs/testshell.key \
+			fs/testshell.sh
+
+
+FSIMGFILES := $(FSIMGTXTFILES) $(USERAPPS)
+
+$(OBJDIR)/fs/%.o: fs/%.c fs/fs.h inc/lib.h $(OBJDIR)/.vars.USER_CFLAGS
+	@echo + cc[USER] $<
+	@mkdir -p $(@D)
+	$(V)$(CC) -nostdinc $(USER_CFLAGS) -c -o $@ $<
+
+$(OBJDIR)/fs/fs: $(FSOFILES) $(OBJDIR)/lib/entry.o $(OBJDIR)/lib/libjos.a user/user.ld
+	@echo + ld $@
+	$(V)mkdir -p $(@D)
+	$(V)$(LD) -o $@ $(ULDFLAGS) $(LDFLAGS) -nostdlib \
+		$(OBJDIR)/lib/entry.o $(FSOFILES) \
+		-L$(OBJDIR)/lib -ljos $(GCC_LIB)
+	$(V)$(OBJDUMP) -S $@ >$@.asm
+
+# How to build the file system image
+$(OBJDIR)/fs/fsformat: fs/fsformat.c
+	@echo + mk $(OBJDIR)/fs/fsformat
+	$(V)mkdir -p $(@D)
+	$(V)$(NCC) $(NATIVE_CFLAGS) -o $(OBJDIR)/fs/fsformat fs/fsformat.c
+
+$(OBJDIR)/fs/clean-fs.img: $(OBJDIR)/fs/fsformat $(FSIMGFILES)
+	@echo + mk $(OBJDIR)/fs/clean-fs.img
+	$(V)mkdir -p $(@D)
+	$(V)$(OBJDIR)/fs/fsformat $(OBJDIR)/fs/clean-fs.img 1024 $(FSIMGFILES)
+
+$(OBJDIR)/fs/fs.img: $(OBJDIR)/fs/clean-fs.img
+	@echo + cp $(OBJDIR)/fs/clean-fs.img $@
+	$(V)cp $(OBJDIR)/fs/clean-fs.img $@
+
+all: $(OBJDIR)/fs/fs.img
+
+#all: $(addsuffix .sym, $(USERAPPS))
+
+#all: $(addsuffix .asm, $(USERAPPS))
+
diff --git a/fs/bc.c b/fs/bc.c
@@ -0,0 +1,151 @@
+
+#include "fs.h"
+
+// Return the virtual address of this disk block.
+void*
+diskaddr(uint32_t blockno)
+{
+	if (blockno == 0 || (super && blockno >= super->s_nblocks))
+		panic("bad block number %08x in diskaddr", blockno);
+	return (char*) (DISKMAP + blockno * BLKSIZE);
+}
+
+// Is this virtual address mapped?
+bool
+va_is_mapped(void *va)
+{
+	return (uvpd[PDX(va)] & PTE_P) && (uvpt[PGNUM(va)] & PTE_P);
+}
+
+// Is this virtual address dirty?
+bool
+va_is_dirty(void *va)
+{
+	return (uvpt[PGNUM(va)] & PTE_D) != 0;
+}
+
+// Fault any disk block that is read in to memory by
+// loading it from disk.
+static void
+bc_pgfault(struct UTrapframe *utf)
+{
+	void *addr = (void *) utf->utf_fault_va;
+	uint32_t blockno = ((uint32_t)addr - DISKMAP) / BLKSIZE;
+	int r;
+
+	// Check that the fault was within the block cache region
+	if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
+		panic("page fault in FS: eip %08x, va %08x, err %04x",
+		      utf->utf_eip, addr, utf->utf_err);
+
+	// Sanity check the block number.
+	if (super && blockno >= super->s_nblocks)
+		panic("reading non-existent block %08x\n", blockno);
+
+	// Allocate a page in the disk map region, read the contents
+	// of the block from the disk into that page.
+	// Hint: first round addr to page boundary. fs/ide.c has code to read
+	// the disk.
+	//
+	// LAB 5: you code here:
+
+	// Clear the dirty bit for the disk block page since we just read the
+	// block from disk
+	if ((r = sys_page_map(0, addr, 0, addr, uvpt[PGNUM(addr)] & PTE_SYSCALL)) < 0)
+		panic("in bc_pgfault, sys_page_map: %e", r);
+
+	// Check that the block we read was allocated. (exercise for
+	// the reader: why do we do this *after* reading the block
+	// in?)
+	if (bitmap && block_is_free(blockno))
+		panic("reading free block %08x\n", blockno);
+}
+
+// Flush the contents of the block containing VA out to disk if
+// necessary, then clear the PTE_D bit using sys_page_map.
+// If the block is not in the block cache or is not dirty, does
+// nothing.
+// Hint: Use va_is_mapped, va_is_dirty, and ide_write.
+// Hint: Use the PTE_SYSCALL constant when calling sys_page_map.
+// Hint: Don't forget to round addr down.
+void
+flush_block(void *addr)
+{
+	uint32_t blockno = ((uint32_t)addr - DISKMAP) / BLKSIZE;
+
+	if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
+		panic("flush_block of bad va %08x", addr);
+
+	// LAB 5: Your code here.
+	panic("flush_block not implemented");
+}
+
+// Test that the block cache works, by smashing the superblock and
+// reading it back.
+static void
+check_bc(void)
+{
+	struct Super backup;
+
+	// back up super block
+	memmove(&backup, diskaddr(1), sizeof backup);
+
+	// smash it
+	strcpy(diskaddr(1), "OOPS!\n");
+	flush_block(diskaddr(1));
+	assert(va_is_mapped(diskaddr(1)));
+	assert(!va_is_dirty(diskaddr(1)));
+
+	// clear it out
+	sys_page_unmap(0, diskaddr(1));
+	assert(!va_is_mapped(diskaddr(1)));
+
+	// read it back in
+	assert(strcmp(diskaddr(1), "OOPS!\n") == 0);
+
+	// fix it
+	memmove(diskaddr(1), &backup, sizeof backup);
+	flush_block(diskaddr(1));
+
+	// Now repeat the same experiment, but pass an unaligned address to
+	// flush_block.
+
+	// back up super block
+	memmove(&backup, diskaddr(1), sizeof backup);
+
+	// smash it
+	strcpy(diskaddr(1), "OOPS!\n");
+
+	// Pass an unaligned address to flush_block.
+	flush_block(diskaddr(1) + 20);
+	assert(va_is_mapped(diskaddr(1)));
+
+	// Skip the !va_is_dirty() check because it makes the bug somewhat
+	// obscure and hence harder to debug.
+	//assert(!va_is_dirty(diskaddr(1)));
+
+	// clear it out
+	sys_page_unmap(0, diskaddr(1));
+	assert(!va_is_mapped(diskaddr(1)));
+
+	// read it back in
+	assert(strcmp(diskaddr(1), "OOPS!\n") == 0);
+
+	// fix it
+	memmove(diskaddr(1), &backup, sizeof backup);
+	flush_block(diskaddr(1));
+
+	cprintf("block cache is good\n");
+}
+
+void
+bc_init(void)
+{
+	struct Super super;
+	set_pgfault_handler(bc_pgfault);
+	check_bc();
+
+	// cache the super block by reading it once
+	memmove(&super, diskaddr(1), sizeof super);
+}
+