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/*
* linux/fs/hpfs/buffer.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* general buffer i/o
*/
#include <linux/string.h>
#include "hpfs_fn.h"
void hpfs_lock_creation(struct super_block *s)
{
#ifdef DEBUG_LOCKS
printk("lock creation\n");
#endif
while (s->s_hpfs_creation_de_lock) sleep_on(&s->s_hpfs_creation_de);
s->s_hpfs_creation_de_lock = 1;
}
void hpfs_unlock_creation(struct super_block *s)
{
#ifdef DEBUG_LOCKS
printk("unlock creation\n");
#endif
s->s_hpfs_creation_de_lock = 0;
wake_up(&s->s_hpfs_creation_de);
}
void hpfs_lock_iget(struct super_block *s, int mode)
{
#ifdef DEBUG_LOCKS
printk("lock iget\n");
#endif
while (s->s_hpfs_rd_inode) sleep_on(&s->s_hpfs_iget_q);
s->s_hpfs_rd_inode = mode;
}
void hpfs_unlock_iget(struct super_block *s)
{
#ifdef DEBUG_LOCKS
printk("unlock iget\n");
#endif
s->s_hpfs_rd_inode = 0;
wake_up(&s->s_hpfs_iget_q);
}
void hpfs_lock_inode(struct inode *i)
{
if (i) down(&i->i_hpfs_sem);
}
void hpfs_unlock_inode(struct inode *i)
{
if (i) up(&i->i_hpfs_sem);
}
void hpfs_lock_2inodes(struct inode *i1, struct inode *i2)
{
if (!i1) { if (i2) down(&i2->i_hpfs_sem); return; }
if (!i2) { if (i1) down(&i1->i_hpfs_sem); return; }
if (i1->i_ino < i2->i_ino) {
down(&i1->i_hpfs_sem);
down(&i2->i_hpfs_sem);
} else if (i1->i_ino > i2->i_ino) {
down(&i2->i_hpfs_sem);
down(&i1->i_hpfs_sem);
} else down(&i1->i_hpfs_sem);
}
void hpfs_unlock_2inodes(struct inode *i1, struct inode *i2)
{
if (!i1) { if (i2) up(&i2->i_hpfs_sem); return; }
if (!i2) { if (i1) up(&i1->i_hpfs_sem); return; }
if (i1->i_ino < i2->i_ino) {
up(&i2->i_hpfs_sem);
up(&i1->i_hpfs_sem);
} else if (i1->i_ino > i2->i_ino) {
up(&i1->i_hpfs_sem);
up(&i2->i_hpfs_sem);
} else up(&i1->i_hpfs_sem);
}
void hpfs_lock_3inodes(struct inode *i1, struct inode *i2, struct inode *i3)
{
if (!i1) { hpfs_lock_2inodes(i2, i3); return; }
if (!i2) { hpfs_lock_2inodes(i1, i3); return; }
if (!i3) { hpfs_lock_2inodes(i1, i2); return; }
if (i1->i_ino < i2->i_ino && i1->i_ino < i3->i_ino) {
down(&i1->i_hpfs_sem);
hpfs_lock_2inodes(i2, i3);
} else if (i2->i_ino < i1->i_ino && i2->i_ino < i3->i_ino) {
down(&i2->i_hpfs_sem);
hpfs_lock_2inodes(i1, i3);
} else if (i3->i_ino < i1->i_ino && i3->i_ino < i2->i_ino) {
down(&i3->i_hpfs_sem);
hpfs_lock_2inodes(i1, i2);
} else if (i1->i_ino != i2->i_ino) hpfs_lock_2inodes(i1, i2);
else hpfs_lock_2inodes(i1, i3);
}
void hpfs_unlock_3inodes(struct inode *i1, struct inode *i2, struct inode *i3)
{
if (!i1) { hpfs_unlock_2inodes(i2, i3); return; }
if (!i2) { hpfs_unlock_2inodes(i1, i3); return; }
if (!i3) { hpfs_unlock_2inodes(i1, i2); return; }
if (i1->i_ino < i2->i_ino && i1->i_ino < i3->i_ino) {
hpfs_unlock_2inodes(i2, i3);
up(&i1->i_hpfs_sem);
} else if (i2->i_ino < i1->i_ino && i2->i_ino < i3->i_ino) {
hpfs_unlock_2inodes(i1, i3);
up(&i2->i_hpfs_sem);
} else if (i3->i_ino < i1->i_ino && i3->i_ino < i2->i_ino) {
hpfs_unlock_2inodes(i1, i2);
up(&i3->i_hpfs_sem);
} else if (i1->i_ino != i2->i_ino) hpfs_unlock_2inodes(i1, i2);
else hpfs_unlock_2inodes(i1, i3);
}
/* 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;
*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);*/
if ((*bhp = bh = sb_getblk(s, secno)) != NULL) {
if (!buffer_uptodate(bh)) wait_on_buffer(bh);
mark_buffer_uptodate(bh, 1);
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;
if (secno & 3) {
printk("HPFS: hpfs_map_4sectors: unaligned read\n");
return 0;
}
qbh->data = data = (char *)kmalloc(2048, GFP_KERNEL);
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)
{
if (secno & 3) {
printk("HPFS: hpfs_get_4sectors: unaligned read\n");
return 0;
}
/*return hpfs_map_4sectors(s, secno, qbh, 0);*/
if (!(qbh->data = kmalloc(2048, GFP_KERNEL))) {
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]);
}
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