disk method support error

addr/addr.go

@@ -1,7 +1,7 @@
 package addr
 
 import (
-	"github.com/tchajed/goose/machine/disk"
+	"github.com/mit-pdos/go-journal/disk"
 
 	"github.com/mit-pdos/go-journal/common"
 )

buf/buf.go

@@ -2,7 +2,7 @@
 package buf
 
 import (
-	"github.com/tchajed/goose/machine/disk"
+	"github.com/mit-pdos/go-journal/disk"
 	"github.com/tchajed/marshal"
 
 	"github.com/mit-pdos/go-journal/addr"
@@ -93,14 +93,17 @@ func (buf *Buf) SetDirty() {
 	buf.dirty = true
 }
 
-func (buf *Buf) WriteDirect(d disk.Disk) {
+func (buf *Buf) WriteDirect(d disk.Disk) error {
 	buf.SetDirty()
 	if buf.Sz == disk.BlockSize {
-		d.Write(uint64(buf.Addr.Blkno), buf.Data)
+		return d.Write(uint64(buf.Addr.Blkno), buf.Data)
 	} else {
-		blk := d.Read(uint64(buf.Addr.Blkno))
+		blk, err := d.Read(uint64(buf.Addr.Blkno))
+		if err != nil {
+			return err
+		}
 		buf.Install(blk)
-		d.Write(uint64(buf.Addr.Blkno), blk)
+		return d.Write(uint64(buf.Addr.Blkno), blk)
 	}
 }
 

buf/buf_test.go

@@ -1,7 +1,7 @@
 package buf
 
 import (
-	"github.com/tchajed/goose/machine/disk"
+	"github.com/mit-pdos/go-journal/disk"
 
 	"testing"
 

common/common.go

@@ -1,7 +1,7 @@
 package common
 
 import (
-	"github.com/tchajed/goose/machine/disk"
+	"github.com/mit-pdos/go-journal/disk"
 )
 
 const (

disk/disk.go

@@ -0,0 +1,36 @@
+package disk
+
+// Block is a 4096-byte buffer
+type Block = []byte
+
+const BlockSize uint64 = 4096 //128 // 32 // 4096
+
+// Disk provides access to a logical block-based disk
+type Disk interface {
+	// Read reads a disk block by address
+	//
+	// Expects a < Size().
+	Read(a uint64) (Block, error)
+
+	// ReadTo reads the disk block at a and stores the result in b
+	//
+	// Expects a < Size().
+	ReadTo(a uint64, b Block) error
+
+	// Write updates a disk block by address
+	//
+	// Expects a < Size().
+	Write(a uint64, v Block) error
+
+	// Size reports how big the disk is, in blocks
+	Size() (uint64, error)
+
+	// Barrier ensures data is persisted.
+	//
+	// When it returns, all outstanding writes are guaranteed to be durably on
+	// disk
+	Barrier() error
+
+	// Close releases any resources used by the disk and makes it unusable.
+	Close() error
+}

disk/disk_impl.go

@@ -0,0 +1,147 @@
+package disk
+
+import (
+	"fmt"
+	"sync"
+
+	"golang.org/x/sys/unix"
+)
+
+var _ Disk = (*fileDisk)(nil)
+
+type fileDisk struct {
+	fd        int
+	numBlocks uint64
+}
+
+func NewFileDisk(path string, numBlocks uint64) (fileDisk, error) {
+	fd, err := unix.Open(path, unix.O_RDWR|unix.O_CREAT, 0666)
+	if err != nil {
+		return fileDisk{}, err
+	}
+	var stat unix.Stat_t
+	err = unix.Fstat(fd, &stat)
+	if err != nil {
+		return fileDisk{}, err
+	}
+	if (stat.Mode&unix.S_IFREG) != 0 && uint64(stat.Size) != numBlocks {
+		err = unix.Ftruncate(fd, int64(numBlocks*BlockSize))
+		if err != nil {
+			return fileDisk{}, err
+		}
+	}
+	return fileDisk{fd, numBlocks}, nil
+}
+
+// var _ Disk = FileDisk{}
+
+func (d fileDisk) ReadTo(a uint64, buf Block) error {
+	if uint64(len(buf)) != BlockSize {
+		panic("buffer is not block-sized")
+	}
+	if a >= d.numBlocks {
+		panic(fmt.Errorf("out-of-bounds read at %v", a))
+	}
+	_, err := unix.Pread(d.fd, buf, int64(a*BlockSize))
+	if err != nil {
+		panic("read failed: " + err.Error())
+	}
+	fmt.Printf("read: %v-%v\n", a, buf)
+	return nil
+}
+
+func (d fileDisk) Read(a uint64) (Block, error) {
+	buf := make([]byte, BlockSize)
+	err := d.ReadTo(a, buf)
+	return buf, err
+}
+
+func (d fileDisk) Write(a uint64, v Block) error {
+	if uint64(len(v)) != BlockSize {
+		panic(fmt.Errorf("v is not block sized (%d bytes)", len(v)))
+	}
+	if a >= d.numBlocks {
+		panic(fmt.Errorf("out-of-bounds write at %v", a))
+	}
+	_, err := unix.Pwrite(d.fd, v, int64(a*BlockSize))
+	if err != nil {
+		panic("write failed: " + err.Error())
+	}
+	fmt.Printf("write: %v-%v\n", a, v)
+	return nil
+}
+
+func (d fileDisk) Size() (uint64, error) {
+	return d.numBlocks, nil
+}
+
+func (d fileDisk) Barrier() error {
+	// NOTE: on macOS, this flushes to the drive but doesn't actually issue a
+	// disk barrier; see https://golang.org/src/internal/poll/fd_fsync_darwin.go
+	// for more details. The correct replacement is to issue a fcntl syscall with
+	// cmd F_FULLFSYNC.
+	err := unix.Fsync(d.fd)
+	if err != nil {
+		panic("file sync failed: " + err.Error())
+	}
+	fmt.Printf("barrier\n")
+	return nil
+}
+
+func (d fileDisk) Close() error {
+	err := unix.Close(d.fd)
+	if err != nil {
+		panic(err)
+	}
+	return nil
+}
+
+var _ Disk = (*memDisk)(nil)
+
+type memDisk struct {
+	l      *sync.RWMutex
+	blocks [][BlockSize]byte
+}
+
+func NewMemDisk(numBlocks uint64) memDisk {
+	blocks := make([][BlockSize]byte, numBlocks)
+	return memDisk{l: new(sync.RWMutex), blocks: blocks}
+}
+
+func (d memDisk) ReadTo(a uint64, buf Block) error {
+	d.l.RLock()
+	defer d.l.RUnlock()
+	if a >= uint64(len(d.blocks)) {
+		panic(fmt.Errorf("out-of-bounds read at %v", a))
+	}
+	copy(buf, d.blocks[a][:])
+	return nil
+}
+
+func (d memDisk) Read(a uint64) (Block, error) {
+	buf := make(Block, BlockSize)
+	d.ReadTo(a, buf)
+	return buf, nil
+}
+
+func (d memDisk) Write(a uint64, v Block) error {
+	if uint64(len(v)) != BlockSize {
+		panic(fmt.Errorf("v is not block-sized (%d bytes)", len(v)))
+	}
+	d.l.Lock()
+	defer d.l.Unlock()
+	if a >= uint64(len(d.blocks)) {
+		panic(fmt.Errorf("out-of-bounds write at %v", a))
+	}
+	copy(d.blocks[a][:], v)
+	return nil
+}
+
+func (d memDisk) Size() (uint64, error) {
+	// this never changes so we assume it's safe to run lock-free
+	return uint64(len(d.blocks)), nil
+}
+
+func (d memDisk) Barrier() error { return nil }
+
+func (d memDisk) Close() error { return nil }

go.mod

@@ -6,5 +6,5 @@ require (
 	github.com/stretchr/testify v1.8.4
 	github.com/tchajed/goose v0.5.3
 	github.com/tchajed/marshal v0.4.3
-	golang.org/x/sys v0.16.0 // indirect
+	golang.org/x/sys v0.6.0
 )

go.sum

@@ -38,7 +38,6 @@ github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
-github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
@@ -48,15 +47,13 @@ github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXl
 github.com/tchajed/goose v0.0.0-20191114201541-ebbf1d75c8ca/go.mod h1:2c33VcNcIHG8vQhprFmBlZxpC62+TfmnGjB+jVaKhXo=
 github.com/tchajed/goose v0.0.0-20200128225509-92a5cfe01fc4/go.mod h1:rhep/Jc/mYPoMIYG8dPtnc71UHAPHNYRx1qvpB245Ss=
 github.com/tchajed/goose v0.2.0/go.mod h1:Y2zBxxd3wa0lrYRDyebxZgbgV4LLsPUtsBiLe1wnS9c=
-github.com/tchajed/goose v0.3.1 h1:pofh2XDZR5lt+WYgKBZbHwyD2QPgea/37gRbLa2AecI=
 github.com/tchajed/goose v0.3.1/go.mod h1:s6D4ibH0SaPtDcp0krx05XkZLlqipgRyRH8X6JP+hcc=
 github.com/tchajed/goose v0.4.4/go.mod h1:w5NCIqICRsj0OJfTuft7HO2H51u629Qn0d+wxZsu6Eo=
 github.com/tchajed/goose v0.5.3 h1:+Ag8wwWfsQZfsTSW953HfDvJmzQ6YopLsfnTNzcd/ZE=
 github.com/tchajed/goose v0.5.3/go.mod h1:ISQLiMmllwxTyKhi5wn/PKE3CeseL6Jnvv3CCWOHvVE=
 github.com/tchajed/mailboat v0.0.0-20191026015926-338a5b81ac1d/go.mod h1:dmgNTEH0kreeKMWd+ntzsrp7ie2LWHGMe7VxP6d1Aew=
 github.com/tchajed/mailboat v0.2.0/go.mod h1:aKa/T1YCMVZFM2xbXnMNyp9r4k0pPni4+sJ8GoY51Hw=
 github.com/tchajed/marshal v0.0.0-20200707011626-0d2aa09818a9/go.mod h1:TPo3bTYJkH87/4rXlxe0bpVWLnN+b5kjJnoXHLBfdaA=
-github.com/tchajed/marshal v0.2.0 h1:6syf2SG3//AE891aHhj6BS+fv3OCMxFM322x05ot3QE=
 github.com/tchajed/marshal v0.2.0/go.mod h1:jq2B5uP+QvY51sZB57Td/OsareaZEzm3HVuvVKhC22I=
 github.com/tchajed/marshal v0.4.3 h1:dnLvl3JDzWMAj2xyCSWxiOr5PcZlu++KdPdl1/Ts51g=
 github.com/tchajed/marshal v0.4.3/go.mod h1:tdiYzC42jUHdvBWrJYa7LytEbHEV2zA+nI3TLLb/nvU=
@@ -99,18 +96,15 @@ golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210823070655-63515b42dcdf h1:2ucpDCmfkl8Bd/FsLtiD653Wf96cW37s+iGx93zsu4k=
-golang.org/x/sys v0.0.0-20210823070655-63515b42dcdf/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20211019181941-9d821ace8654/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220319134239-a9b59b0215f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
@@ -139,7 +133,6 @@ gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.5/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 h1:tQIYjPdBoyREyB9XMu+nnTclpTYkz2zFM+lzLJFO4gQ=
 gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

jrnl/jrnl.go

@@ -35,16 +35,18 @@ package jrnl
 import (
 	"github.com/mit-pdos/go-journal/addr"
 	"github.com/mit-pdos/go-journal/buf"
+	"github.com/mit-pdos/go-journal/disk"
 	"github.com/mit-pdos/go-journal/obj"
 	"github.com/mit-pdos/go-journal/util"
+	"github.com/mit-pdos/go-journal/wal"
 )
 
 // LogBlocks is the maximum number of blocks that can be written in one
 // operation
-const LogBlocks uint64 = 511
+const LogBlocks uint64 = wal.LOGSZ //3
 
 // LogBytes is the maximum size of an operation, in bytes
-const LogBytes uint64 = 4096 * 511
+const LogBytes uint64 = disk.BlockSize * LogBlocks
 
 // Op is an in-progress journal operation.
 //
@@ -66,14 +68,17 @@ func Begin(log *obj.Log) *Op {
 	return trans
 }
 
-func (op *Op) ReadBuf(addr addr.Addr, sz uint64) *buf.Buf {
+func (op *Op) ReadBuf(addr addr.Addr, sz uint64) (*buf.Buf, error) {
 	b := op.bufs.Lookup(addr)
 	if b == nil {
-		buf := op.log.Load(addr, sz)
+		buf, err := op.log.Load(addr, sz)
+		if err != nil {
+			return nil, err
+		}
 		op.bufs.Insert(buf)
-		return op.bufs.Lookup(addr)
+		return op.bufs.Lookup(addr), nil
 	}
-	return b
+	return b, nil
 }
 
 // OverWrite writes an object to addr
@@ -111,8 +116,8 @@ func (op *Op) NDirty() uint64 {
 //
 // wait=false is an asynchronous commit, which can be made durable later with
 // Flush.
-func (op *Op) CommitWait(wait bool) bool {
+func (op *Op) CommitWait(wait bool) error {
 	util.DPrintf(3, "Commit %p w %v\n", op, wait)
-	ok := op.log.CommitWait(op.bufs.DirtyBufs(), wait)
-	return ok
+	err := op.log.CommitWait(op.bufs.DirtyBufs(), wait)
+	return err
 }