[mirror_ubuntu-bionic-kernel.git] / fs / reiserfs / resize.c

/*
 * 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 "reiserfs.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;
	int depth;

	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 */
	depth = reiserfs_write_unlock_nested(s);
	bh = sb_bread(s, block_count_new - 1);
	reiserfs_write_lock_nested(s, depth);
	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 i
		 * 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 =
		    vzalloc(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;
		}
		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++) {
			int depth;
			/*
			 * don't use read_bitmap_block since it will cache
			 * the uninitialized bitmap
			 */
			depth = reiserfs_write_unlock_nested(s);
			bh = sb_bread(s, i * s->s_blocksize * 8);
			reiserfs_write_lock_nested(s, depth);
			if (!bh) {
				vfree(bitmap);
				return -EIO;
			}
			memset(bh->b_data, 0, sb_blocksize(sb));
			reiserfs_set_le_bit(0, bh->b_data);
			reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);

			set_buffer_uptodate(bh);
			mark_buffer_dirty(bh);
			depth = reiserfs_write_unlock_nested(s);
			sync_dirty_buffer(bh);
			reiserfs_write_lock_nested(s, depth);
			/* 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);
		if (jerr)
			return jerr;
		return -EIO;
	}

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

	journal_mark_dirty(&th, 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);
		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_set_le_bit(i, bh->b_data);
	journal_mark_dirty(&th, 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);

	journal_mark_dirty(&th, SB_BUFFER_WITH_SB(s));

	SB_JOURNAL(s)->j_must_wait = 1;
	return journal_end(&th);
}
Commit	Line	Data
0222e657	1	/*
1da177e4 LT	2	* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
1da177e4 LT	3	*/
bd4c625c	4
0222e657	5	/*
1da177e4 LT	6	* Written by Alexander Zarochentcev.
	7	*
	8	* The kernel part of the (on-line) reiserfs resizer.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/mm.h>
	13	#include <linux/vmalloc.h>
	14	#include <linux/string.h>
	15	#include <linux/errno.h>
f466c6fd	16	#include "reiserfs.h"
1da177e4 LT	17	#include <linux/buffer_head.h>
1da177e4 LT	18
bd4c625c	19	int reiserfs_resize(struct super_block *s, unsigned long block_count_new)
1da177e4	20	{
bd4c625c LT	21	int err = 0;
	22	struct reiserfs_super_block *sb;
	23	struct reiserfs_bitmap_info *bitmap;
0b3dc17b	24	struct reiserfs_bitmap_info *info;
1da177e4	25	struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s);
bd4c625c	26	struct buffer_head *bh;
1da177e4 LT	27	struct reiserfs_transaction_handle th;
	28	unsigned int bmap_nr_new, bmap_nr;
	29	unsigned int block_r_new, block_r;
bd4c625c LT	30
bd4c625c LT	31	struct reiserfs_list_bitmap *jb;
1da177e4	32	struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];
bd4c625c	33
1da177e4 LT	34	unsigned long int block_count, free_blocks;
1da177e4 LT	35	int i;
bd4c625c	36	int copy_size;
278f6679	37	int depth;
1da177e4 LT	38
	39	sb = SB_DISK_SUPER_BLOCK(s);
	40
	41	if (SB_BLOCK_COUNT(s) >= block_count_new) {
	42	printk("can\'t shrink filesystem on-line\n");
	43	return -EINVAL;
	44	}
	45
	46	/* check the device size */
278f6679	47	depth = reiserfs_write_unlock_nested(s);
1da177e4	48	bh = sb_bread(s, block_count_new - 1);
278f6679	49	reiserfs_write_lock_nested(s, depth);
1da177e4 LT	50	if (!bh) {
	51	printk("reiserfs_resize: can\'t read last block\n");
	52	return -EINVAL;
bd4c625c	53	}
1da177e4 LT	54	bforget(bh);
1da177e4 LT	55
098297b2 JM	56	/*
	57	* old disk layout detection; those partitions can be mounted, but
	58	* cannot be resized
	59	*/
bd4c625c LT	60	if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
	61	!= REISERFS_DISK_OFFSET_IN_BYTES) {
	62	printk
	63	("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
1da177e4 LT	64	return -ENOTSUPP;
1da177e4 LT	65	}
bd4c625c	66
1da177e4	67	/* count used bits in last bitmap block */
cb680c1b JM	68	block_r = SB_BLOCK_COUNT(s) -
cb680c1b JM	69	(reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8;
bd4c625c	70
1da177e4	71	/* count bitmap blocks in new fs */
bd4c625c	72	bmap_nr_new = block_count_new / (s->s_blocksize * 8);
1da177e4	73	block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
bd4c625c	74	if (block_r_new)
1da177e4 LT	75	bmap_nr_new++;
	76	else
	77	block_r_new = s->s_blocksize * 8;
	78
	79	/* save old values */
	80	block_count = SB_BLOCK_COUNT(s);
cb680c1b	81	bmap_nr = reiserfs_bmap_count(s);
1da177e4 LT	82
1da177e4 LT	83	/* resizing of reiserfs bitmaps (journal and real), if needed */
bd4c625c LT	84	if (bmap_nr_new > bmap_nr) {
	85	/* reallocate journal bitmaps */
	86	if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
	87	printk
	88	("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
bd4c625c LT	89	return -ENOMEM;
bd4c625c LT	90	}
098297b2 JM	91	/*
	92	* the new journal bitmaps are zero filled, now we copy i
	93	* the bitmap node pointers from the old journal bitmap
	94	* structs, and then transfer the new data structures
	95	* into the journal struct.
	96	*
	97	* using the copy_size var below allows this code to work for
	98	* both shrinking and expanding the FS.
bd4c625c LT	99	*/
	100	copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr;
	101	copy_size =
	102	copy_size * sizeof(struct reiserfs_list_bitmap_node *);
	103	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
	104	struct reiserfs_bitmap_node **node_tmp;
	105	jb = SB_JOURNAL(s)->j_list_bitmap + i;
	106	memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size);
	107
098297b2 JM	108	/*
	109	* just in case vfree schedules on us, copy the new
	110	* pointer into the journal struct before freeing the
	111	* old one
bd4c625c LT	112	*/
	113	node_tmp = jb->bitmaps;
	114	jb->bitmaps = jbitmap[i].bitmaps;
	115	vfree(node_tmp);
	116	}
	117
098297b2 JM	118	/*
	119	* allocate additional bitmap blocks, reallocate
	120	* array of bitmap block pointers
	121	*/
bd4c625c	122	bitmap =
558feb08	123	vzalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
bd4c625c	124	if (!bitmap) {
098297b2 JM	125	/*
	126	* Journal bitmaps are still supersized, but the
	127	* memory isn't leaked, so I guess it's ok
	128	*/
bd4c625c LT	129	printk("reiserfs_resize: unable to allocate memory.\n");
	130	return -ENOMEM;
	131	}
bd4c625c LT	132	for (i = 0; i < bmap_nr; i++)
	133	bitmap[i] = old_bitmap[i];
	134
098297b2 JM	135	/*
	136	* This doesn't go through the journal, but it doesn't have to.
	137	* The changes are still atomic: We're synced up when the
	138	* journal transaction begins, and the new bitmaps don't
	139	* matter if the transaction fails.
	140	*/
bd4c625c	141	for (i = bmap_nr; i < bmap_nr_new; i++) {
278f6679	142	int depth;
098297b2 JM	143	/*
	144	* don't use read_bitmap_block since it will cache
	145	* the uninitialized bitmap
	146	*/
278f6679	147	depth = reiserfs_write_unlock_nested(s);
5065227b	148	bh = sb_bread(s, i * s->s_blocksize * 8);
278f6679	149	reiserfs_write_lock_nested(s, depth);
2d3466a3 DM	150	if (!bh) {
	151	vfree(bitmap);
	152	return -EIO;
	153	}
0b3dc17b	154	memset(bh->b_data, 0, sb_blocksize(sb));
0c2fd1bf	155	reiserfs_set_le_bit(0, bh->b_data);
6f01046b	156	reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);
0b3dc17b JM	157
	158	set_buffer_uptodate(bh);
	159	mark_buffer_dirty(bh);
278f6679	160	depth = reiserfs_write_unlock_nested(s);
0b3dc17b	161	sync_dirty_buffer(bh);
278f6679	162	reiserfs_write_lock_nested(s, depth);
098297b2	163	/* update bitmap_info stuff */
bd4c625c	164	bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
0b3dc17b	165	brelse(bh);
bd4c625c LT	166	}
	167	/* free old bitmap blocks array */
	168	SB_AP_BITMAP(s) = bitmap;
	169	vfree(old_bitmap);
1da177e4	170	}
bd4c625c	171
098297b2 JM	172	/*
098297b2 JM	173	* begin transaction, if there was an error, it's fine. Yes, we have
1da177e4	174	* incorrect bitmaps now, but none of it is ever going to touch the
098297b2 JM	175	* disk anyway.
098297b2 JM	176	*/
1da177e4 LT	177	err = journal_begin(&th, s, 10);
1da177e4 LT	178	if (err)
bd4c625c	179	return err;
1da177e4	180
0b3dc17b JM	181	/* Extend old last bitmap block - new blocks have been made available */
0b3dc17b JM	182	info = SB_AP_BITMAP(s) + bmap_nr - 1;
5065227b JM	183	bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
5065227b JM	184	if (!bh) {
58d85426	185	int jerr = journal_end(&th);
5065227b JM	186	if (jerr)
	187	return jerr;
	188	return -EIO;
	189	}
0b3dc17b JM	190
0b3dc17b JM	191	reiserfs_prepare_for_journal(s, bh, 1);
1da177e4	192	for (i = block_r; i < s->s_blocksize * 8; i++)
0c2fd1bf	193	reiserfs_clear_le_bit(i, bh->b_data);
0b3dc17b	194	info->free_count += s->s_blocksize * 8 - block_r;
0b3dc17b	195
09f1b80b	196	journal_mark_dirty(&th, bh);
0b3dc17b	197	brelse(bh);
1da177e4	198
0b3dc17b JM	199	/* Correct new last bitmap block - It may not be full */
0b3dc17b JM	200	info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
5065227b JM	201	bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
5065227b JM	202	if (!bh) {
58d85426	203	int jerr = journal_end(&th);
5065227b JM	204	if (jerr)
	205	return jerr;
	206	return -EIO;
	207	}
1da177e4	208
0b3dc17b	209	reiserfs_prepare_for_journal(s, bh, 1);
1da177e4	210	for (i = block_r_new; i < s->s_blocksize * 8; i++)
0c2fd1bf	211	reiserfs_set_le_bit(i, bh->b_data);
09f1b80b	212	journal_mark_dirty(&th, bh);
0b3dc17b	213	brelse(bh);
bd4c625c	214
0b3dc17b	215	info->free_count -= s->s_blocksize * 8 - block_r_new;
bd4c625c LT	216	/* update super */
bd4c625c LT	217	reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
1da177e4	218	free_blocks = SB_FREE_BLOCKS(s);
bd4c625c LT	219	PUT_SB_FREE_BLOCKS(s,
	220	free_blocks + (block_count_new - block_count -
	221	(bmap_nr_new - bmap_nr)));
1da177e4	222	PUT_SB_BLOCK_COUNT(s, block_count_new);
cb680c1b	223	PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new);
1da177e4	224
09f1b80b	225	journal_mark_dirty(&th, SB_BUFFER_WITH_SB(s));
bd4c625c	226
1da177e4	227	SB_JOURNAL(s)->j_must_wait = 1;
58d85426	228	return journal_end(&th);
1da177e4	229	}