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change ip->flags&I_VALID to ip->valid

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This commit is contained in:
Robert Morris 2017-08-08 13:34:13 -04:00
parent 14270288b7
commit 3375df5061
2 changed files with 11 additions and 12 deletions
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3
file.h
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@ -15,7 +15,7 @@ struct inode {
uint inum; // Inode number
int ref; // Reference count
struct sleeplock lock;
int flags; // I_VALID
int valid; // remainder has been read from disk?
short type; // copy of disk inode
short major;
@ -24,7 +24,6 @@ struct inode {
uint size;
uint addrs[NDIRECT+1];
};
#define I_VALID 0x2
// table mapping major device number to
// device functions

20
fs.c
View file

@ -110,7 +110,7 @@ bfree(int dev, uint b)
// to provide a place for synchronizing access
// to inodes used by multiple processes. The cached
// inodes include book-keeping information that is
// not stored on disk: ip->ref and ip->flags.
// not stored on disk: ip->ref and ip->valid.
//
// An inode and its in-memory representation go through a
// sequence of states before they can be used by the
@ -128,10 +128,10 @@ bfree(int dev, uint b)
// decrements ref.
//
// * Valid: the information (type, size, &c) in an inode
// cache entry is only correct when the I_VALID bit
// is set in ip->flags. ilock() reads the inode from
// the disk and sets I_VALID, while iput() clears
// I_VALID if ip->ref has fallen to zero.
// cache entry is only correct when ip->valid is 1.
// ilock() reads the inode from
// the disk and sets ip->valid, while iput() clears
// ip->valid if ip->ref has fallen to zero.
//
// * Locked: file system code may only examine and modify
// the information in an inode and its content if it
@ -253,7 +253,7 @@ iget(uint dev, uint inum)
ip->dev = dev;
ip->inum = inum;
ip->ref = 1;
ip->flags = 0;
ip->valid = 0;
release(&icache.lock);
return ip;
@ -283,7 +283,7 @@ ilock(struct inode *ip)
acquiresleep(&ip->lock);
if((ip->flags & I_VALID) == 0){
if(ip->valid == 0){
bp = bread(ip->dev, IBLOCK(ip->inum, sb));
dip = (struct dinode*)bp->data + ip->inum%IPB;
ip->type = dip->type;
@ -293,7 +293,7 @@ ilock(struct inode *ip)
ip->size = dip->size;
memmove(ip->addrs, dip->addrs, sizeof(ip->addrs));
brelse(bp);
ip->flags |= I_VALID;
ip->valid = 1;
if(ip->type == 0)
panic("ilock: no type");
}
@ -320,7 +320,7 @@ void
iput(struct inode *ip)
{
acquire(&icache.lock);
if(ip->ref == 1 && (ip->flags & I_VALID) && ip->nlink == 0){
if(ip->ref == 1 && ip->valid && ip->nlink == 0){
// inode has no links and no other references: truncate and free.
acquiresleep(&ip->lock);
release(&icache.lock);
@ -328,7 +328,7 @@ iput(struct inode *ip)
ip->type = 0;
iupdate(ip);
acquire(&icache.lock);
ip->flags = 0;
ip->valid = 0;
releasesleep(&ip->lock);
}
ip->ref--;