[linux.git] / fs / hpfs / buffer.c

/*
 *  linux/fs/hpfs/buffer.c
 *
 *  Mikulas Patocka ([email protected]), 1998-1999
 *
 *  general buffer i/o
 */
#include <linux/sched.h>
#include <linux/slab.h>
#include "hpfs_fn.h"

void hpfs_lock_creation(struct super_block *s)
{
#ifdef DEBUG_LOCKS
	printk("lock creation\n");
#endif
	down(&hpfs_sb(s)->hpfs_creation_de);
}

void hpfs_unlock_creation(struct super_block *s)
{
#ifdef DEBUG_LOCKS
	printk("unlock creation\n");
#endif
	up(&hpfs_sb(s)->hpfs_creation_de);
}

/* Map a sector into a buffer and return pointers to it and to the buffer. */

void *hpfs_map_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp,
		 int ahead)
{
	struct buffer_head *bh;

	cond_resched();

	*bhp = bh = sb_bread(s, secno);
	if (bh != NULL)
		return bh->b_data;
	else {
		printk("HPFS: hpfs_map_sector: read error\n");
		return NULL;
	}
}

/* Like hpfs_map_sector but don't read anything */

void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp)
{
	struct buffer_head *bh;
	/*return hpfs_map_sector(s, secno, bhp, 0);*/

	cond_resched();

	if ((*bhp = bh = sb_getblk(s, secno)) != NULL) {
		if (!buffer_uptodate(bh)) wait_on_buffer(bh);
		set_buffer_uptodate(bh);
		return bh->b_data;
	} else {
		printk("HPFS: hpfs_get_sector: getblk failed\n");
		return NULL;
	}
}

/* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */

void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh,
		   int ahead)
{
	struct buffer_head *bh;
	char *data;

	cond_resched();

	if (secno & 3) {
		printk("HPFS: hpfs_map_4sectors: unaligned read\n");
		return NULL;
	}

	qbh->data = data = kmalloc(2048, GFP_NOFS);
	if (!data) {
		printk("HPFS: hpfs_map_4sectors: out of memory\n");
		goto bail;
	}

	qbh->bh[0] = bh = sb_bread(s, secno);
	if (!bh)
		goto bail0;
	memcpy(data, bh->b_data, 512);

	qbh->bh[1] = bh = sb_bread(s, secno + 1);
	if (!bh)
		goto bail1;
	memcpy(data + 512, bh->b_data, 512);

	qbh->bh[2] = bh = sb_bread(s, secno + 2);
	if (!bh)
		goto bail2;
	memcpy(data + 2 * 512, bh->b_data, 512);

	qbh->bh[3] = bh = sb_bread(s, secno + 3);
	if (!bh)
		goto bail3;
	memcpy(data + 3 * 512, bh->b_data, 512);

	return data;

 bail3:
	brelse(qbh->bh[2]);
 bail2:
	brelse(qbh->bh[1]);
 bail1:
	brelse(qbh->bh[0]);
 bail0:
	kfree(data);
	printk("HPFS: hpfs_map_4sectors: read error\n");
 bail:
	return NULL;
}

/* Don't read sectors */

void *hpfs_get_4sectors(struct super_block *s, unsigned secno,
                          struct quad_buffer_head *qbh)
{
	cond_resched();

	if (secno & 3) {
		printk("HPFS: hpfs_get_4sectors: unaligned read\n");
		return NULL;
	}

	/*return hpfs_map_4sectors(s, secno, qbh, 0);*/
	if (!(qbh->data = kmalloc(2048, GFP_NOFS))) {
		printk("HPFS: hpfs_get_4sectors: out of memory\n");
		return NULL;
	}
	if (!(hpfs_get_sector(s, secno, &qbh->bh[0]))) goto bail0;
	if (!(hpfs_get_sector(s, secno + 1, &qbh->bh[1]))) goto bail1;
	if (!(hpfs_get_sector(s, secno + 2, &qbh->bh[2]))) goto bail2;
	if (!(hpfs_get_sector(s, secno + 3, &qbh->bh[3]))) goto bail3;
	memcpy(qbh->data, qbh->bh[0]->b_data, 512);
	memcpy(qbh->data + 512, qbh->bh[1]->b_data, 512);
	memcpy(qbh->data + 2*512, qbh->bh[2]->b_data, 512);
	memcpy(qbh->data + 3*512, qbh->bh[3]->b_data, 512);
	return qbh->data;

	bail3:	brelse(qbh->bh[2]);
	bail2:	brelse(qbh->bh[1]);
	bail1:	brelse(qbh->bh[0]);
	bail0:
	return NULL;
}
	

void hpfs_brelse4(struct quad_buffer_head *qbh)
{
	brelse(qbh->bh[3]);
	brelse(qbh->bh[2]);
	brelse(qbh->bh[1]);
	brelse(qbh->bh[0]);
	kfree(qbh->data);
}	

void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh)
{
	PRINTK(("hpfs_mark_4buffers_dirty\n"));
	memcpy(qbh->bh[0]->b_data, qbh->data, 512);
	memcpy(qbh->bh[1]->b_data, qbh->data + 512, 512);
	memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512);
	memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512);
	mark_buffer_dirty(qbh->bh[0]);
	mark_buffer_dirty(qbh->bh[1]);
	mark_buffer_dirty(qbh->bh[2]);
	mark_buffer_dirty(qbh->bh[3]);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/hpfs/buffer.c
	3	*
	4	* Mikulas Patocka ([email protected]), 1998-1999
	5	*
	6	* general buffer i/o
	7	*/
e8edc6e0	8	#include <linux/sched.h>
5a0e3ad6	9	#include <linux/slab.h>
1da177e4 LT	10	#include "hpfs_fn.h"
	11
	12	void hpfs_lock_creation(struct super_block *s)
	13	{
	14	#ifdef DEBUG_LOCKS
	15	printk("lock creation\n");
	16	#endif
	17	down(&hpfs_sb(s)->hpfs_creation_de);
	18	}
	19
	20	void hpfs_unlock_creation(struct super_block *s)
	21	{
	22	#ifdef DEBUG_LOCKS
	23	printk("unlock creation\n");
	24	#endif
	25	up(&hpfs_sb(s)->hpfs_creation_de);
	26	}
	27
	28	/* Map a sector into a buffer and return pointers to it and to the buffer. */
	29
	30	void hpfs_map_sector(struct super_block s, unsigned secno, struct buffer_head **bhp,
	31	int ahead)
	32	{
	33	struct buffer_head *bh;
	34
	35	cond_resched();
	36
	37	*bhp = bh = sb_bread(s, secno);
	38	if (bh != NULL)
	39	return bh->b_data;
	40	else {
	41	printk("HPFS: hpfs_map_sector: read error\n");
	42	return NULL;
	43	}
	44	}
	45
	46	/* Like hpfs_map_sector but don't read anything */
	47
	48	void hpfs_get_sector(struct super_block s, unsigned secno, struct buffer_head **bhp)
	49	{
	50	struct buffer_head *bh;
	51	/return hpfs_map_sector(s, secno, bhp, 0);/
	52
	53	cond_resched();
	54
	55	if ((*bhp = bh = sb_getblk(s, secno)) != NULL) {
	56	if (!buffer_uptodate(bh)) wait_on_buffer(bh);
	57	set_buffer_uptodate(bh);
	58	return bh->b_data;
	59	} else {
	60	printk("HPFS: hpfs_get_sector: getblk failed\n");
	61	return NULL;
	62	}
	63	}
	64
	65	/* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */
	66
	67	void hpfs_map_4sectors(struct super_block s, unsigned secno, struct quad_buffer_head *qbh,
	68	int ahead)
	69	{
	70	struct buffer_head *bh;
	71	char *data;
	72
	73	cond_resched();
74
75	if (secno & 3) {
76	printk("HPFS: hpfs_map_4sectors: unaligned read\n");
77	return NULL;
78	}
79
f52720ca	80	qbh->data = data = kmalloc(2048, GFP_NOFS);
1da177e4 LT	81	if (!data) {
	82	printk("HPFS: hpfs_map_4sectors: out of memory\n");
	83	goto bail;
	84	}
	85
	86	qbh->bh[0] = bh = sb_bread(s, secno);
	87	if (!bh)
	88	goto bail0;
	89	memcpy(data, bh->b_data, 512);
	90
	91	qbh->bh[1] = bh = sb_bread(s, secno + 1);
	92	if (!bh)
	93	goto bail1;
	94	memcpy(data + 512, bh->b_data, 512);
	95
	96	qbh->bh[2] = bh = sb_bread(s, secno + 2);
	97	if (!bh)
	98	goto bail2;
	99	memcpy(data + 2 * 512, bh->b_data, 512);
	100
	101	qbh->bh[3] = bh = sb_bread(s, secno + 3);
	102	if (!bh)
	103	goto bail3;
	104	memcpy(data + 3 * 512, bh->b_data, 512);
	105
	106	return data;
	107
	108	bail3:
	109	brelse(qbh->bh[2]);
	110	bail2:
	111	brelse(qbh->bh[1]);
	112	bail1:
	113	brelse(qbh->bh[0]);
	114	bail0:
	115	kfree(data);
	116	printk("HPFS: hpfs_map_4sectors: read error\n");
	117	bail:
	118	return NULL;
	119	}
	120
	121	/* Don't read sectors */
	122
	123	void hpfs_get_4sectors(struct super_block s, unsigned secno,
	124	struct quad_buffer_head *qbh)
	125	{
	126	cond_resched();
	127
	128	if (secno & 3) {
	129	printk("HPFS: hpfs_get_4sectors: unaligned read\n");
	130	return NULL;
	131	}
	132
	133	/return hpfs_map_4sectors(s, secno, qbh, 0);/
	134	if (!(qbh->data = kmalloc(2048, GFP_NOFS))) {
	135	printk("HPFS: hpfs_get_4sectors: out of memory\n");
	136	return NULL;
	137	}
	138	if (!(hpfs_get_sector(s, secno, &qbh->bh[0]))) goto bail0;
	139	if (!(hpfs_get_sector(s, secno + 1, &qbh->bh[1]))) goto bail1;
	140	if (!(hpfs_get_sector(s, secno + 2, &qbh->bh[2]))) goto bail2;
	141	if (!(hpfs_get_sector(s, secno + 3, &qbh->bh[3]))) goto bail3;
	142	memcpy(qbh->data, qbh->bh[0]->b_data, 512);
	143	memcpy(qbh->data + 512, qbh->bh[1]->b_data, 512);
	144	memcpy(qbh->data + 2*512, qbh->bh[2]->b_data, 512);
145	memcpy(qbh->data + 3*512, qbh->bh[3]->b_data, 512);
146	return qbh->data;
147
148	bail3: brelse(qbh->bh[2]);
149	bail2: brelse(qbh->bh[1]);
150	bail1: brelse(qbh->bh[0]);
151	bail0:
152	return NULL;
153	}
154
155
156	void hpfs_brelse4(struct quad_buffer_head *qbh)
157	{
158	brelse(qbh->bh[3]);
159	brelse(qbh->bh[2]);
160	brelse(qbh->bh[1]);
161	brelse(qbh->bh[0]);
162	kfree(qbh->data);
163	}
164
165	void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh)
166	{
167	PRINTK(("hpfs_mark_4buffers_dirty\n"));
168	memcpy(qbh->bh[0]->b_data, qbh->data, 512);
169	memcpy(qbh->bh[1]->b_data, qbh->data + 512, 512);
170	memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512);
171	memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512);
172	mark_buffer_dirty(qbh->bh[0]);
173	mark_buffer_dirty(qbh->bh[1]);
174	mark_buffer_dirty(qbh->bh[2]);
175	mark_buffer_dirty(qbh->bh[3]);
176	}