uint dev; // Device number
uint inum; // Inode number
int ref; // Reference count
- int flags; // I_BUSY, I_VALID
+ struct sleeplock lock;
+ int flags; // I_VALID
short type; // copy of disk inode
short major;
uint size;
uint addrs[NDIRECT+1];
};
-#define I_BUSY 0x1
#define I_VALID 0x2
// table mapping major device number to
//
// * Locked: file system code may only examine and modify
// the information in an inode and its content if it
-// has first locked the inode. The I_BUSY flag indicates
-// that the inode is locked. ilock() sets I_BUSY,
-// while iunlock clears it.
+// has first locked the inode.
//
// Thus a typical sequence is:
// ip = iget(dev, inum)
void
iinit(int dev)
{
+ int i = 0;
+
initlock(&icache.lock, "icache");
+ for(i = 0; i < NINODE; i++) {
+ initsleeplock(&icache.inode[i].lock, "inode");
+ }
+
readsb(dev, &sb);
cprintf("sb: size %d nblocks %d ninodes %d nlog %d logstart %d\
inodestart %d bmap start %d\n", sb.size, sb.nblocks,
if(ip == 0 || ip->ref < 1)
panic("ilock");
- acquire(&icache.lock);
- while(ip->flags & I_BUSY)
- sleep(ip, &icache.lock);
- ip->flags |= I_BUSY;
- release(&icache.lock);
+ acquiresleep(&ip->lock);
if(!(ip->flags & I_VALID)){
bp = bread(ip->dev, IBLOCK(ip->inum, sb));
void
iunlock(struct inode *ip)
{
- if(ip == 0 || !(ip->flags & I_BUSY) || ip->ref < 1)
+ if(ip == 0 || !holdingsleep(&ip->lock) || ip->ref < 1)
panic("iunlock");
- acquire(&icache.lock);
- ip->flags &= ~I_BUSY;
- wakeup(ip);
- release(&icache.lock);
+ releasesleep(&ip->lock);
}
// Drop a reference to an in-memory inode.
acquire(&icache.lock);
if(ip->ref == 1 && (ip->flags & I_VALID) && ip->nlink == 0){
// inode has no links and no other references: truncate and free.
- if(ip->flags & I_BUSY)
- panic("iput busy");
- ip->flags |= I_BUSY;
release(&icache.lock);
itrunc(ip);
ip->type = 0;
iupdate(ip);
acquire(&icache.lock);
ip->flags = 0;
- wakeup(ip);
}
ip->ref--;
release(&icache.lock);