patch-2.1.21 linux/fs/ext/freelists.c

• Lines: 342
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v2.1.20/linux/fs/ext/freelists.c
• Orig date: Sun Nov 26 19:23:10 1995

diff -u --recursive --new-file v2.1.20/linux/fs/ext/freelists.c linux/fs/ext/freelists.c
@@ -1,341 +0,0 @@
-/*
- *  linux/fs/ext/freelists.c
- *
- *  Copyright (C) 1992  Remy Card (card@masi.ibp.fr)
- *
- */
-
-/* freelists.c contains the code that handles the inode and block free lists */
-
-
-/*
-
-   The free blocks are managed by a linked list. The super block contains the
-   number of the first free block. This block contains 254 numbers of other
-   free blocks and the number of the next block in the list.
-
-   When an ext fs is mounted, the number of the first free block is stored
-   in s->u.ext_sb.s_firstfreeblocknumber and the block header is stored in
-   s->u.ext_sb.s_firstfreeblock. u.ext_sb.s_freeblockscount contains the count
-   of free blocks.
-
-   The free inodes are also managed by a linked list in a similar way. The
-   super block contains the number of the first free inode. This inode contains
-   14 numbers of other free inodes and the number of the next inode in the list.
-   
-   The number of the first free inode is stored in
-   s->u.ext_sb.s_firstfreeinodenumber and the header of the block containing
-   the inode is stored in s->u.ext_sb.s_firstfreeinodeblock.
-   u.ext_sb.s_freeinodescount contains the count of free inodes.
-
-*/
-
-#include <linux/sched.h>
-#include <linux/ext_fs.h>
-#include <linux/stat.h>
-#include <linux/kernel.h>
-#include <linux/string.h>
-#include <linux/locks.h>
-
-void ext_free_block(struct super_block * sb, int block)
-{
-	struct buffer_head * bh;
-	struct ext_free_block * efb;
-
-	if (!sb) {
-		printk("trying to free block on non-existent device\n");
-		return;
-	}
-	lock_super (sb);
-	if (block < sb->u.ext_sb.s_firstdatazone ||
-	    block >= sb->u.ext_sb.s_nzones) {
-		printk("trying to free block not in datazone\n");
-		return;
-	}
-	bh = get_hash_table(sb->s_dev, block, sb->s_blocksize);
-	if (bh)
-		mark_buffer_clean(bh);
-	brelse(bh);
-	if (sb->u.ext_sb.s_firstfreeblock)
-		efb = (struct ext_free_block *) sb->u.ext_sb.s_firstfreeblock->b_data;
-	if (!sb->u.ext_sb.s_firstfreeblock || efb->count == 254) {
-#ifdef EXTFS_DEBUG
-printk("ext_free_block: block full, skipping to %d\n", block);
-#endif
-		if (sb->u.ext_sb.s_firstfreeblock)
-			brelse (sb->u.ext_sb.s_firstfreeblock);
-		if (!(sb->u.ext_sb.s_firstfreeblock = bread (sb->s_dev,
-			block, sb->s_blocksize)))
-			panic ("ext_free_block: unable to read block to free\n");
-		efb = (struct ext_free_block *) sb->u.ext_sb.s_firstfreeblock->b_data;
-		efb->next = sb->u.ext_sb.s_firstfreeblocknumber;
-		efb->count = 0;
-		sb->u.ext_sb.s_firstfreeblocknumber = block;
-	} else {
-		efb->free[efb->count++] = block;
-	}
-	sb->u.ext_sb.s_freeblockscount ++;
-	sb->s_dirt = 1;
-	mark_buffer_dirty(sb->u.ext_sb.s_firstfreeblock, 1);
-	unlock_super (sb);
-	return;
-}
-
-int ext_new_block(struct super_block * sb)
-{
-	struct buffer_head * bh;
-	struct ext_free_block * efb;
-	int j;
-
-	if (!sb) {
-		printk("trying to get new block from non-existent device\n");
-		return 0;
-	}
-	if (!sb->u.ext_sb.s_firstfreeblock)
-		return 0;
-	lock_super (sb);
-	efb = (struct ext_free_block *) sb->u.ext_sb.s_firstfreeblock->b_data;
-	if (efb->count) {
-		j = efb->free[--efb->count];
-		mark_buffer_dirty(sb->u.ext_sb.s_firstfreeblock, 1);
-	} else {
-#ifdef EXTFS_DEBUG
-printk("ext_new_block: block empty, skipping to %d\n", efb->next);
-#endif
-		j = sb->u.ext_sb.s_firstfreeblocknumber;
-		sb->u.ext_sb.s_firstfreeblocknumber = efb->next;
-		brelse (sb->u.ext_sb.s_firstfreeblock);
-		if (!sb->u.ext_sb.s_firstfreeblocknumber) {
-			sb->u.ext_sb.s_firstfreeblock = NULL;
-		} else {
-			if (!(sb->u.ext_sb.s_firstfreeblock = bread (sb->s_dev,
-				sb->u.ext_sb.s_firstfreeblocknumber,
-				sb->s_blocksize)))
-				panic ("ext_new_block: unable to read next free block\n");
-		}
-	}
-	if (j < sb->u.ext_sb.s_firstdatazone || j > sb->u.ext_sb.s_nzones) {
-		printk ("ext_new_block: blk = %d\n", j);
-		printk("allocating block not in data zone\n");
-		return 0;
-	}
-	sb->u.ext_sb.s_freeblockscount --;
-	sb->s_dirt = 1;
-
-	if (!(bh=getblk(sb->s_dev, j, sb->s_blocksize))) {
-		printk("new_block: cannot get block");
-		return 0;
-	}
-	memset(bh->b_data, 0, BLOCK_SIZE);
-	mark_buffer_uptodate(bh, 1);
-	mark_buffer_dirty(bh, 1);
-	brelse(bh);
-#ifdef EXTFS_DEBUG
-printk("ext_new_block: allocating block %d\n", j);
-#endif
-	unlock_super (sb);
-	return j;
-}
-
-unsigned long ext_count_free_blocks(struct super_block *sb)
-{
-#ifdef EXTFS_DEBUG
-	struct buffer_head * bh;
-	struct ext_free_block * efb;
-	unsigned long count, block;
-
-	lock_super (sb);
-	if (!sb->u.ext_sb.s_firstfreeblock)
-		count = 0;
-	else {
-		efb = (struct ext_free_block *) sb->u.ext_sb.s_firstfreeblock->b_data;
-		count = efb->count + 1;
-		block = efb->next;
-		while (block) {
-			if (!(bh = bread (sb->s_dev, block, sb->s_blocksize))) {
-				printk ("ext_count_free: error while reading free blocks list\n");
-				block = 0;
-			} else {
-				efb = (struct ext_free_block *) bh->b_data;
-				count += efb->count + 1;
-				block = efb->next;
-				brelse (bh);
-			}
-		}
-	}
-printk("ext_count_free_blocks: stored = %d, computed = %d\n",
-	sb->u.ext_sb.s_freeblockscount, count);
-	unlock_super (sb);
-	return count;
-#else
-	return sb->u.ext_sb.s_freeblockscount;
-#endif
-}
-
-void ext_free_inode(struct inode * inode)
-{
-	struct buffer_head * bh;
-	struct ext_free_inode * efi;
-	struct super_block * sb;
-	unsigned long block;
-	unsigned long ino;
-	kdev_t dev;
-
-	if (!inode)
-		return;
-	if (!inode->i_dev) {
-		printk("free_inode: inode has no device\n");
-		return;
-	}
-	if (inode->i_count != 1) {
-		printk("free_inode: inode has count=%d\n",inode->i_count);
-		return;
-	}
-	if (inode->i_nlink) {
-		printk("free_inode: inode has nlink=%d\n",inode->i_nlink);
-		return;
-	}
-	if (!inode->i_sb) {
-		printk("free_inode: inode on non-existent device\n");
-		return;
-	}
-	sb = inode->i_sb;
-	ino = inode->i_ino;
-	dev = inode->i_dev;
-	clear_inode(inode);
-	lock_super (sb);
-	if (ino < 1 || ino > sb->u.ext_sb.s_ninodes) {
-		printk("free_inode: inode 0 or non-existent inode\n");
-		unlock_super (sb);
-		return;
-	}
-	if (sb->u.ext_sb.s_firstfreeinodeblock)
-		efi = ((struct ext_free_inode *) sb->u.ext_sb.s_firstfreeinodeblock->b_data) +
-			(sb->u.ext_sb.s_firstfreeinodenumber-1)%EXT_INODES_PER_BLOCK;
-	if (!sb->u.ext_sb.s_firstfreeinodeblock || efi->count == 14) {
-#ifdef EXTFS_DEBUG
-printk("ext_free_inode: inode full, skipping to %d\n", ino);
-#endif
-		if (sb->u.ext_sb.s_firstfreeinodeblock)
-			brelse (sb->u.ext_sb.s_firstfreeinodeblock);
-		block = 2 + (ino - 1) / EXT_INODES_PER_BLOCK;
-		if (!(bh = bread(dev, block, sb->s_blocksize)))
-			panic("ext_free_inode: unable to read inode block\n");
-		efi = ((struct ext_free_inode *) bh->b_data) +
-			(ino - 1) % EXT_INODES_PER_BLOCK;
-		efi->next = sb->u.ext_sb.s_firstfreeinodenumber;
-		efi->count = 0;
-		sb->u.ext_sb.s_firstfreeinodenumber = ino;
-		sb->u.ext_sb.s_firstfreeinodeblock = bh;
-	} else {
-		efi->free[efi->count++] = ino;
-	}
-	sb->u.ext_sb.s_freeinodescount ++;
-	sb->s_dirt = 1;
-	mark_buffer_dirty(sb->u.ext_sb.s_firstfreeinodeblock, 1);
-	unlock_super (sb);
-}
-
-struct inode * ext_new_inode(const struct inode * dir)
-{
-	struct super_block * sb;
-	struct inode * inode;
-	struct ext_free_inode * efi;
-	unsigned long block;
-	int j;
-
-	if (!dir || !(inode=get_empty_inode()))
-		return NULL;
-	sb = dir->i_sb;
-	inode->i_sb = sb;
-	inode->i_flags = sb->s_flags;
-	if (!sb->u.ext_sb.s_firstfreeinodeblock)
-		return 0;
-	lock_super (sb);
-	efi = ((struct ext_free_inode *) sb->u.ext_sb.s_firstfreeinodeblock->b_data) +
-		(sb->u.ext_sb.s_firstfreeinodenumber-1)%EXT_INODES_PER_BLOCK;
-	if (efi->count) {
-		j = efi->free[--efi->count];
-		mark_buffer_dirty(sb->u.ext_sb.s_firstfreeinodeblock, 1);
-	} else {
-#ifdef EXTFS_DEBUG
-printk("ext_free_inode: inode empty, skipping to %d\n", efi->next);
-#endif
-		j = sb->u.ext_sb.s_firstfreeinodenumber;
-		if (efi->next > sb->u.ext_sb.s_ninodes) {
-			printk ("efi->next = %ld\n", efi->next);
-			panic ("ext_new_inode: bad inode number in free list\n");
-		}
-		sb->u.ext_sb.s_firstfreeinodenumber = efi->next;
-		block = 2 + (((unsigned long) efi->next) - 1) / EXT_INODES_PER_BLOCK;
-		brelse (sb->u.ext_sb.s_firstfreeinodeblock);
-		if (!sb->u.ext_sb.s_firstfreeinodenumber) {
-			sb->u.ext_sb.s_firstfreeinodeblock = NULL;
-		} else {
-			if (!(sb->u.ext_sb.s_firstfreeinodeblock =
-			    bread(sb->s_dev, block, sb->s_blocksize)))
-				panic ("ext_new_inode: unable to read next free inode block\n");
-		}
-	}
-	sb->u.ext_sb.s_freeinodescount --;
-	sb->s_dirt = 1;
-	inode->i_count = 1;
-	inode->i_nlink = 1;
-	inode->i_dev = sb->s_dev;
-	inode->i_uid = current->fsuid;
-	inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current->fsgid;
-	inode->i_dirt = 1;
-	inode->i_ino = j;
-	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-	inode->i_op = NULL;
-	inode->i_blocks = inode->i_blksize = 0;
-	insert_inode_hash(inode);
-#ifdef EXTFS_DEBUG
-printk("ext_new_inode : allocating inode %d\n", inode->i_ino);
-#endif
-	unlock_super (sb);
-	return inode;
-}
-
-unsigned long ext_count_free_inodes(struct super_block *sb)
-{
-#ifdef EXTFS_DEBUG
-	struct buffer_head * bh;
-	struct ext_free_inode * efi;
-	unsigned long count, block, ino;
-
-	lock_super (sb);
-	if (!sb->u.ext_sb.s_firstfreeinodeblock)
-		count = 0;
-	else {
-		efi = ((struct ext_free_inode *) sb->u.ext_sb.s_firstfreeinodeblock->b_data) +
-			((sb->u.ext_sb.s_firstfreeinodenumber-1)%EXT_INODES_PER_BLOCK);
-		count = efi->count + 1;
-		ino = efi->next;
-		while (ino) {
-			if (ino < 1 || ino > sb->u.ext_sb.s_ninodes) {
-				printk ("u.ext_sb.s_firstfreeinodenumber = %d, ino = %d\n", 
-					(int) sb->u.ext_sb.s_firstfreeinodenumber,ino);
-				panic ("ext_count_fre_inodes: bad inode number in free list\n");
-			}
-			block = 2 + ((ino - 1) / EXT_INODES_PER_BLOCK);
-			if (!(bh = bread (sb->s_dev, block, sb->s_blocksize))) {
-				printk ("ext_count_free_inodes: error while reading free inodes list\n");
-				block = 0;
-			} else {
-				efi = ((struct ext_free_inode *) bh->b_data) +
-					((ino - 1) % EXT_INODES_PER_BLOCK);
-				count += efi->count + 1;
-				ino = efi->next;
-				brelse (bh);
-			}
-		}
-	}
-printk("ext_count_free_inodes: stored = %d, computed = %d\n",
-	sb->u.ext_sb.s_freeinodescount, count);
-	unlock_super (sb);
-	return count;
-#else
-	return sb->u.ext_sb.s_freeinodescount;
-#endif
-}