static void nilfs_cpfile_block_init(struct inode *cpfile,
struct buffer_head *bh,
void *kaddr)
{
struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
int n = nilfs_cpfile_checkpoints_per_block(cpfile);
while (n-- > 0) {
nilfs_checkpoint_set_invalid(cp);
cp = (void *)cp + cpsz;
}
}
/**
* nilfs_cpfile_delete_checkpoints - delete checkpoints
* @cpfile: inode of checkpoint file
* @start: start checkpoint number
* @end: end checkpoint numer
*
* Description: nilfs_cpfile_delete_checkpoints() deletes the checkpoints in
* the period from @start to @end, excluding @end itself. The checkpoints
* which have been already deleted are ignored.
*
* Return Value: On success, 0 is returned. On error, one of the following
* negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - invalid checkpoints.
*/
int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
__u64 start,
__u64 end)
{
struct buffer_head *header_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
__u64 cno;
void *kaddr;
unsigned long tnicps;
int ret, ncps, nicps, nss, count, i;
if (unlikely(start == 0 || start > end)) {
printk(KERN_ERR "%s: invalid range of checkpoint numbers: "
"[%llu, %llu)\n", __func__,
(unsigned long long)start, (unsigned long long)end);
return -EINVAL;
}
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_sem;
tnicps = 0;
nss = 0;
for (cno = start; cno < end; cno += ncps) {
ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, end);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0) {
if (ret != -ENOENT)
break;
/* skip hole */
ret = 0;
continue;
}
kaddr = kmap_atomic(cp_bh->b_page);
cp = nilfs_cpfile_block_get_checkpoint(
cpfile, cno, cp_bh, kaddr);
nicps = 0;
for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
if (nilfs_checkpoint_snapshot(cp)) {
nss++;
} else if (!nilfs_checkpoint_invalid(cp)) {
nilfs_checkpoint_set_invalid(cp);
nicps++;
}
}
if (nicps > 0) {
tnicps += nicps;
mark_buffer_dirty(cp_bh);
nilfs_mdt_mark_dirty(cpfile);
if (!nilfs_cpfile_is_in_first(cpfile, cno)) {
count =
nilfs_cpfile_block_sub_valid_checkpoints(
cpfile, cp_bh, kaddr, nicps);
if (count == 0) {
/* make hole */
kunmap_atomic(kaddr);
brelse(cp_bh);
ret =
nilfs_cpfile_delete_checkpoint_block(
cpfile, cno);
if (ret == 0)
continue;
printk(KERN_ERR
"%s: cannot delete block\n",
__func__);
break;
}
}
}
kunmap_atomic(kaddr);
brelse(cp_bh);
}
if (tnicps > 0) {
kaddr = kmap_atomic(header_bh->b_page);
header = nilfs_cpfile_block_get_header(cpfile, header_bh,
kaddr);
le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps);
mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
kunmap_atomic(kaddr);
}
brelse(header_bh);
if (nss > 0)
ret = -EBUSY;
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
