fs/reiserfs/resize.c - maze/linux - Git at Google

 /*
  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
  */

 /*
  * Written by Alexander Zarochentcev.
  *
  * The kernel part of the (on-line) reiserfs resizer.
  */

 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/reiserfs_fs.h>
 #include <linux/reiserfs_fs_sb.h>
 #include <linux/buffer_head.h>

 int reiserfs_resize(struct super_block *s, unsigned long block_count_new)
 {
 	int err = 0;
 	struct reiserfs_super_block *sb;
 	struct reiserfs_bitmap_info *bitmap;
 	struct reiserfs_bitmap_info *info;
 	struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s);
 	struct buffer_head *bh;
 	struct reiserfs_transaction_handle th;
 	unsigned int bmap_nr_new, bmap_nr;
 	unsigned int block_r_new, block_r;

 	struct reiserfs_list_bitmap *jb;
 	struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];

 	unsigned long int block_count, free_blocks;
 	int i;
 	int copy_size;

 	sb = SB_DISK_SUPER_BLOCK(s);

 	if (SB_BLOCK_COUNT(s) >= block_count_new) {
 		printk("can\'t shrink filesystem on-line\n");
 		return -EINVAL;
 	}

 	/* check the device size */
 	bh = sb_bread(s, block_count_new - 1);
 	if (!bh) {
 		printk("reiserfs_resize: can\'t read last block\n");
 		return -EINVAL;
 	}
 	bforget(bh);

 	/* old disk layout detection; those partitions can be mounted, but
 	 * cannot be resized */
 	if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
 	    != REISERFS_DISK_OFFSET_IN_BYTES) {
 		printk
 		    ("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
 		return -ENOTSUPP;
 	}

 	/* count used bits in last bitmap block */
 	block_r = SB_BLOCK_COUNT(s) -
 			(reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8;

 	/* count bitmap blocks in new fs */
 	bmap_nr_new = block_count_new / (s->s_blocksize * 8);
 	block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
 	if (block_r_new)
 		bmap_nr_new++;
 	else
 		block_r_new = s->s_blocksize * 8;

 	/* save old values */
 	block_count = SB_BLOCK_COUNT(s);
 	bmap_nr = reiserfs_bmap_count(s);

 	/* resizing of reiserfs bitmaps (journal and real), if needed */
 	if (bmap_nr_new > bmap_nr) {
 		/* reallocate journal bitmaps */
 		if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
 			printk
 			    ("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
 			return -ENOMEM;
 		}
 		/* the new journal bitmaps are zero filled, now we copy in the bitmap
 		 ** node pointers from the old journal bitmap structs, and then
 		 ** transfer the new data structures into the journal struct.
 		 **
 		 ** using the copy_size var below allows this code to work for
 		 ** both shrinking and expanding the FS.
 		 */
 		copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr;
 		copy_size =
 		    copy_size * sizeof(struct reiserfs_list_bitmap_node *);
 		for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
 			struct reiserfs_bitmap_node **node_tmp;
 			jb = SB_JOURNAL(s)->j_list_bitmap + i;
 			memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size);

 			/* just in case vfree schedules on us, copy the new
 			 ** pointer into the journal struct before freeing the
 			 ** old one
 			 */
 			node_tmp = jb->bitmaps;
 			jb->bitmaps = jbitmap[i].bitmaps;
 			vfree(node_tmp);
 		}

 		/* allocate additional bitmap blocks, reallocate array of bitmap
 		 * block pointers */
 		bitmap =
 		    vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
 		if (!bitmap) {
 			/* Journal bitmaps are still supersized, but the memory isn't
 			 * leaked, so I guess it's ok */
 			printk("reiserfs_resize: unable to allocate memory.\n");
 			return -ENOMEM;
 		}
 		memset(bitmap, 0,
 		       sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
 		for (i = 0; i < bmap_nr; i++)
 			bitmap[i] = old_bitmap[i];

 		/* This doesn't go through the journal, but it doesn't have to.
 		 * The changes are still atomic: We're synced up when the journal
 		 * transaction begins, and the new bitmaps don't matter if the
 		 * transaction fails. */
 		for (i = bmap_nr; i < bmap_nr_new; i++) {
 			/* don't use read_bitmap_block since it will cache
 			 * the uninitialized bitmap */
 			bh = sb_bread(s, i * s->s_blocksize * 8);
 			if (!bh) {
 				vfree(bitmap);
 				return -EIO;
 			}
 			memset(bh->b_data, 0, sb_blocksize(sb));
 			reiserfs_test_and_set_le_bit(0, bh->b_data);
 			reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);

 			set_buffer_uptodate(bh);
 			mark_buffer_dirty(bh);
 			reiserfs_write_unlock(s);
 			sync_dirty_buffer(bh);
 			reiserfs_write_lock(s);
 			// update bitmap_info stuff
 			bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
 			brelse(bh);
 		}
 		/* free old bitmap blocks array */
 		SB_AP_BITMAP(s) = bitmap;
 		vfree(old_bitmap);
 	}

 	/* begin transaction, if there was an error, it's fine. Yes, we have
 	 * incorrect bitmaps now, but none of it is ever going to touch the
 	 * disk anyway. */
 	err = journal_begin(&th, s, 10);
 	if (err)
 		return err;

 	/* Extend old last bitmap block - new blocks have been made available */
 	info = SB_AP_BITMAP(s) + bmap_nr - 1;
 	bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
 	if (!bh) {
 		int jerr = journal_end(&th, s, 10);
 		if (jerr)
 			return jerr;
 		return -EIO;
 	}

 	reiserfs_prepare_for_journal(s, bh, 1);
 	for (i = block_r; i < s->s_blocksize * 8; i++)
 		reiserfs_test_and_clear_le_bit(i, bh->b_data);
 	info->free_count += s->s_blocksize * 8 - block_r;

 	journal_mark_dirty(&th, s, bh);
 	brelse(bh);

 	/* Correct new last bitmap block - It may not be full */
 	info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
 	bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
 	if (!bh) {
 		int jerr = journal_end(&th, s, 10);
 		if (jerr)
 			return jerr;
 		return -EIO;
 	}

 	reiserfs_prepare_for_journal(s, bh, 1);
 	for (i = block_r_new; i < s->s_blocksize * 8; i++)
 		reiserfs_test_and_set_le_bit(i, bh->b_data);
 	journal_mark_dirty(&th, s, bh);
 	brelse(bh);

 	info->free_count -= s->s_blocksize * 8 - block_r_new;
 	/* update super */
 	reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
 	free_blocks = SB_FREE_BLOCKS(s);
 	PUT_SB_FREE_BLOCKS(s,
 			   free_blocks + (block_count_new - block_count -
 					  (bmap_nr_new - bmap_nr)));
 	PUT_SB_BLOCK_COUNT(s, block_count_new);
 	PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new);
 	s->s_dirt = 1;

 	journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));

 	SB_JOURNAL(s)->j_must_wait = 1;
 	return journal_end(&th, s, 10);
 }
	/*
	* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
	*/

	/*
	* Written by Alexander Zarochentcev.
	*
	* The kernel part of the (on-line) reiserfs resizer.
	*/

	#include <linux/kernel.h>
	#include <linux/mm.h>
	#include <linux/vmalloc.h>
	#include <linux/string.h>
	#include <linux/errno.h>
	#include <linux/reiserfs_fs.h>
	#include <linux/reiserfs_fs_sb.h>
	#include <linux/buffer_head.h>

	int reiserfs_resize(struct super_block *s, unsigned long block_count_new)
	{
	int err = 0;
	struct reiserfs_super_block *sb;
	struct reiserfs_bitmap_info *bitmap;
	struct reiserfs_bitmap_info *info;
	struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s);
	struct buffer_head *bh;
	struct reiserfs_transaction_handle th;
	unsigned int bmap_nr_new, bmap_nr;
	unsigned int block_r_new, block_r;

	struct reiserfs_list_bitmap *jb;
	struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];

	unsigned long int block_count, free_blocks;
	int i;
	int copy_size;

	sb = SB_DISK_SUPER_BLOCK(s);

	if (SB_BLOCK_COUNT(s) >= block_count_new) {
	printk("can\'t shrink filesystem on-line\n");
	return -EINVAL;
	}

	/* check the device size */
	bh = sb_bread(s, block_count_new - 1);
	if (!bh) {
	printk("reiserfs_resize: can\'t read last block\n");
	return -EINVAL;
	}
	bforget(bh);

	/* old disk layout detection; those partitions can be mounted, but
	* cannot be resized */
	if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
	!= REISERFS_DISK_OFFSET_IN_BYTES) {
	printk
	("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
	return -ENOTSUPP;
	}

	/* count used bits in last bitmap block */
	block_r = SB_BLOCK_COUNT(s) -
	(reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8;

	/* count bitmap blocks in new fs */
	bmap_nr_new = block_count_new / (s->s_blocksize * 8);
	block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
	if (block_r_new)
	bmap_nr_new++;
	else
	block_r_new = s->s_blocksize * 8;

	/* save old values */
	block_count = SB_BLOCK_COUNT(s);
	bmap_nr = reiserfs_bmap_count(s);

	/* resizing of reiserfs bitmaps (journal and real), if needed */
	if (bmap_nr_new > bmap_nr) {
	/* reallocate journal bitmaps */
	if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
	printk
	("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
	return -ENOMEM;
	}
	/* the new journal bitmaps are zero filled, now we copy in the bitmap
	** node pointers from the old journal bitmap structs, and then
	** transfer the new data structures into the journal struct.
	**
	** using the copy_size var below allows this code to work for
	** both shrinking and expanding the FS.
	*/
	copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr;
	copy_size =
	copy_size * sizeof(struct reiserfs_list_bitmap_node *);
	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
	struct reiserfs_bitmap_node **node_tmp;
	jb = SB_JOURNAL(s)->j_list_bitmap + i;
	memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size);

	/* just in case vfree schedules on us, copy the new
	** pointer into the journal struct before freeing the
	** old one
	*/
	node_tmp = jb->bitmaps;
	jb->bitmaps = jbitmap[i].bitmaps;
	vfree(node_tmp);
	}

	/* allocate additional bitmap blocks, reallocate array of bitmap
	* block pointers */
	bitmap =
	vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
	if (!bitmap) {
	/* Journal bitmaps are still supersized, but the memory isn't
	* leaked, so I guess it's ok */
	printk("reiserfs_resize: unable to allocate memory.\n");
	return -ENOMEM;
	}
	memset(bitmap, 0,
	sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
	for (i = 0; i < bmap_nr; i++)
	bitmap[i] = old_bitmap[i];

	/* This doesn't go through the journal, but it doesn't have to.
	* The changes are still atomic: We're synced up when the journal
	* transaction begins, and the new bitmaps don't matter if the
	* transaction fails. */
	for (i = bmap_nr; i < bmap_nr_new; i++) {
	/* don't use read_bitmap_block since it will cache
	* the uninitialized bitmap */
	bh = sb_bread(s, i * s->s_blocksize * 8);
	if (!bh) {
	vfree(bitmap);
	return -EIO;
	}
	memset(bh->b_data, 0, sb_blocksize(sb));
	reiserfs_test_and_set_le_bit(0, bh->b_data);
	reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);

	set_buffer_uptodate(bh);
	mark_buffer_dirty(bh);
	reiserfs_write_unlock(s);
	sync_dirty_buffer(bh);
	reiserfs_write_lock(s);
	// update bitmap_info stuff
	bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
	brelse(bh);
	}
	/* free old bitmap blocks array */
	SB_AP_BITMAP(s) = bitmap;
	vfree(old_bitmap);
	}

	/* begin transaction, if there was an error, it's fine. Yes, we have
	* incorrect bitmaps now, but none of it is ever going to touch the
	* disk anyway. */
	err = journal_begin(&th, s, 10);
	if (err)
	return err;

	/* Extend old last bitmap block - new blocks have been made available */
	info = SB_AP_BITMAP(s) + bmap_nr - 1;
	bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
	if (!bh) {
	int jerr = journal_end(&th, s, 10);
	if (jerr)
	return jerr;
	return -EIO;
	}

	reiserfs_prepare_for_journal(s, bh, 1);
	for (i = block_r; i < s->s_blocksize * 8; i++)
	reiserfs_test_and_clear_le_bit(i, bh->b_data);
	info->free_count += s->s_blocksize * 8 - block_r;

	journal_mark_dirty(&th, s, bh);
	brelse(bh);

	/* Correct new last bitmap block - It may not be full */
	info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
	bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
	if (!bh) {
	int jerr = journal_end(&th, s, 10);
	if (jerr)
	return jerr;
	return -EIO;
	}

	reiserfs_prepare_for_journal(s, bh, 1);
	for (i = block_r_new; i < s->s_blocksize * 8; i++)
	reiserfs_test_and_set_le_bit(i, bh->b_data);
	journal_mark_dirty(&th, s, bh);
	brelse(bh);

	info->free_count -= s->s_blocksize * 8 - block_r_new;
	/* update super */
	reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
	free_blocks = SB_FREE_BLOCKS(s);
	PUT_SB_FREE_BLOCKS(s,
	free_blocks + (block_count_new - block_count -
	(bmap_nr_new - bmap_nr)));
	PUT_SB_BLOCK_COUNT(s, block_count_new);
	PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new);
	s->s_dirt = 1;

	journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));

	SB_JOURNAL(s)->j_must_wait = 1;
	return journal_end(&th, s, 10);
	}