/**
* nilfs_palloc_commit_free_entry - finish deallocating a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the removal
*/
void nilfs_palloc_commit_free_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
struct nilfs_palloc_group_desc *desc;
unsigned long group, group_offset;
unsigned char *bitmap;
void *desc_kaddr, *bitmap_kaddr;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
desc_kaddr = kmap(req->pr_desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(inode, group,
req->pr_desc_bh, desc_kaddr);
bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group),
group_offset, bitmap))
printk(KERN_WARNING "%s: entry number %llu already freed\n",
__func__, (unsigned long long)req->pr_entry_nr);
nilfs_palloc_group_desc_add_entries(inode, group, desc, 1);
kunmap(req->pr_bitmap_bh->b_page);
kunmap(req->pr_desc_bh->b_page);
nilfs_mdt_mark_buffer_dirty(req->pr_desc_bh);
nilfs_mdt_mark_buffer_dirty(req->pr_bitmap_bh);
nilfs_mdt_mark_dirty(inode);
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
}
int nilfs_cpfile_get_checkpoint(struct inode *cpfile,
__u64 cno,
int create,
struct nilfs_checkpoint **cpp,
struct buffer_head **bhp)
{
struct buffer_head *header_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
void *kaddr;
int ret;
if (unlikely(cno < 1 || cno > nilfs_mdt_cno(cpfile) ||
(cno < nilfs_mdt_cno(cpfile) && create)))
return -EINVAL;
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_sem;
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, create, &cp_bh);
if (ret < 0)
goto out_header;
kaddr = kmap(cp_bh->b_page);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
if (nilfs_checkpoint_invalid(cp)) {
if (!create) {
kunmap(cp_bh->b_page);
brelse(cp_bh);
ret = -ENOENT;
goto out_header;
}
/* a newly-created checkpoint */
nilfs_checkpoint_clear_invalid(cp);
if (!nilfs_cpfile_is_in_first(cpfile, cno))
nilfs_cpfile_block_add_valid_checkpoints(cpfile, cp_bh,
kaddr, 1);
nilfs_mdt_mark_buffer_dirty(cp_bh);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh,
kaddr);
le64_add_cpu(&header->ch_ncheckpoints, 1);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
}
if (cpp != NULL)
*cpp = cp;
*bhp = cp_bh;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
/**
* nilfs_palloc_commit_alloc_entry - finish allocation of a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the allocation
*/
void nilfs_palloc_commit_alloc_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
nilfs_mdt_mark_buffer_dirty(req->pr_bitmap_bh);
nilfs_mdt_mark_buffer_dirty(req->pr_desc_bh);
nilfs_mdt_mark_dirty(inode);
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
}
/**
* nilfs_palloc_freev - deallocate a set of persistent objects
* @inode: inode of metadata file using this allocator
* @entry_nrs: array of entry numbers to be deallocated
* @nitems: number of entries stored in @entry_nrs
*/
int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
{
struct buffer_head *desc_bh, *bitmap_bh;
struct nilfs_palloc_group_desc *desc;
unsigned char *bitmap;
void *desc_kaddr, *bitmap_kaddr;
unsigned long group, group_offset;
int i, j, n, ret;
for (i = 0; i < nitems; i = j) {
group = nilfs_palloc_group(inode, entry_nrs[i], &group_offset);
ret = nilfs_palloc_get_desc_block(inode, group, 0, &desc_bh);
if (ret < 0)
return ret;
ret = nilfs_palloc_get_bitmap_block(inode, group, 0,
&bitmap_bh);
if (ret < 0) {
brelse(desc_bh);
return ret;
}
desc_kaddr = kmap(desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(
inode, group, desc_bh, desc_kaddr);
bitmap_kaddr = kmap(bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
for (j = i, n = 0;
(j < nitems) && nilfs_palloc_group_is_in(inode, group,
entry_nrs[j]);
j++) {
nilfs_palloc_group(inode, entry_nrs[j], &group_offset);
if (!nilfs_clear_bit_atomic(
nilfs_mdt_bgl_lock(inode, group),
group_offset, bitmap)) {
printk(KERN_WARNING
"%s: entry number %llu already freed\n",
__func__,
(unsigned long long)entry_nrs[j]);
} else {
n++;
}
}
nilfs_palloc_group_desc_add_entries(inode, group, desc, n);
kunmap(bitmap_bh->b_page);
kunmap(desc_bh->b_page);
nilfs_mdt_mark_buffer_dirty(desc_bh);
nilfs_mdt_mark_buffer_dirty(bitmap_bh);
nilfs_mdt_mark_dirty(inode);
brelse(bitmap_bh);
brelse(desc_bh);
}
return 0;
}
static void nilfs_dat_commit_entry(struct inode *dat,
struct nilfs_palloc_req *req)
{
nilfs_mdt_mark_buffer_dirty(req->pr_entry_bh);
nilfs_mdt_mark_dirty(dat);
brelse(req->pr_entry_bh);
}
void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int clean, dirty;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) &&
su->su_nblocks == cpu_to_le32(0)) {
kunmap_atomic(kaddr, KM_USER0);
return;
}
clean = nilfs_segment_usage_clean(su);
dirty = nilfs_segment_usage_dirty(su);
/* make the segment garbage */
su->su_lastmod = cpu_to_le64(0);
su->su_nblocks = cpu_to_le32(0);
su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY);
kunmap_atomic(kaddr, KM_USER0);
nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
/**
* nilfs_ifile_delete_inode - delete a disk inode
* @ifile: ifile inode
* @ino: inode number
*
* 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.
*
* %-ENOENT - The inode number @ino have not been allocated.
*/
int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
{
struct nilfs_palloc_req req = {
.pr_entry_nr = ino, .pr_entry_bh = NULL
};
struct nilfs_inode *raw_inode;
void *kaddr;
int ret;
ret = nilfs_palloc_prepare_free_entry(ifile, &req);
if (!ret) {
ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
&req.pr_entry_bh);
if (ret < 0)
nilfs_palloc_abort_free_entry(ifile, &req);
}
if (ret < 0) {
brelse(req.pr_entry_bh);
return ret;
}
kaddr = kmap_atomic(req.pr_entry_bh->b_page, KM_USER0);
raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
req.pr_entry_bh, kaddr);
raw_inode->i_flags = 0;
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
brelse(req.pr_entry_bh);
nilfs_palloc_commit_free_entry(ifile, &req);
return 0;
}
void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int sudirty;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_clean(su)) {
printk(KERN_WARNING "%s: segment %llu is already clean\n",
__func__, (unsigned long long)segnum);
kunmap_atomic(kaddr, KM_USER0);
return;
}
WARN_ON(nilfs_segment_usage_error(su));
WARN_ON(!nilfs_segment_usage_dirty(su));
sudirty = nilfs_segment_usage_dirty(su);
nilfs_segment_usage_set_clean(su);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
nilfs_mdt_mark_dirty(sufile);
}
void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int suclean;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_error(su)) {
kunmap_atomic(kaddr, KM_USER0);
return;
}
suclean = nilfs_segment_usage_clean(su);
nilfs_segment_usage_set_error(su);
kunmap_atomic(kaddr, KM_USER0);
if (suclean) {
nilfs_sufile_mod_counter(header_bh, -1, 0);
NILFS_SUI(sufile)->ncleansegs--;
}
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
unsigned long nblocks, time_t modtime)
{
struct buffer_head *bh;
struct nilfs_segment_usage *su;
void *kaddr;
int ret;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
WARN_ON(nilfs_segment_usage_error(su));
if (modtime)
su->su_lastmod = cpu_to_le64(modtime);
su->su_nblocks = cpu_to_le32(nblocks);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_dat_move - change a block number
* @dat: DAT file inode
* @vblocknr: virtual block number
* @blocknr: block number
*
* Description: nilfs_dat_move() changes the block number associated with
* @vblocknr to @blocknr.
*
* 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.
*/
int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
{
struct buffer_head *entry_bh;
struct nilfs_dat_entry *entry;
void *kaddr;
int ret;
ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
if (ret < 0)
return ret;
kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
(unsigned long long)vblocknr,
(unsigned long long)le64_to_cpu(entry->de_start),
(unsigned long long)le64_to_cpu(entry->de_end));
kunmap_atomic(kaddr, KM_USER0);
brelse(entry_bh);
return -EINVAL;
}
WARN_ON(blocknr == 0);
entry->de_blocknr = cpu_to_le64(blocknr);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(entry_bh);
nilfs_mdt_mark_dirty(dat);
brelse(entry_bh);
return 0;
}
/**
* nilfs_ifile_create_inode - create a new disk inode
* @ifile: ifile inode
* @out_ino: pointer to a variable to store inode number
* @out_bh: buffer_head contains newly allocated disk inode
*
* Return Value: On success, 0 is returned and the newly allocated inode
* number is stored in the place pointed by @ino, and buffer_head pointer
* that contains newly allocated disk inode structure is stored in the
* place pointed by @out_bh
* On error, one of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No inode left.
*/
int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
struct buffer_head **out_bh)
{
struct nilfs_palloc_req req;
int ret;
req.pr_entry_nr = 0; /* 0 says find free inode from beginning of
a group. dull code!! */
req.pr_entry_bh = NULL;
ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
if (!ret) {
ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
&req.pr_entry_bh);
if (ret < 0)
nilfs_palloc_abort_alloc_entry(ifile, &req);
}
if (ret < 0) {
brelse(req.pr_entry_bh);
return ret;
}
nilfs_palloc_commit_alloc_entry(ifile, &req);
nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
nilfs_mdt_mark_dirty(ifile);
*out_ino = (ino_t)req.pr_entry_nr;
*out_bh = req.pr_entry_bh;
return 0;
}
int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
{
struct buffer_head *bh;
int ret;
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (!ret) {
nilfs_mdt_mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
}
return ret;
}
int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *bh)
{
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
return -EIO;
if (buffer_dirty(bh))
return -EEXIST;
if (buffer_nilfs_node(bh))
nilfs_btnode_mark_dirty(bh);
else
nilfs_mdt_mark_buffer_dirty(bh);
return 0;
}
static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
u64 ncleanadd, u64 ndirtyadd)
{
struct nilfs_sufile_header *header;
void *kaddr;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(header_bh);
}
int nilfs_mark_inode_dirty(struct inode *inode)
{
struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
struct buffer_head *ibh;
int err;
err = nilfs_load_inode_block(sbi, inode, &ibh);
if (unlikely(err)) {
nilfs_warning(inode->i_sb, __func__,
"failed to reget inode block.\n");
return err;
}
lock_buffer(ibh);
nilfs_update_inode(inode, ibh);
unlock_buffer(ibh);
nilfs_mdt_mark_buffer_dirty(ibh);
nilfs_mdt_mark_dirty(sbi->s_ifile);
brelse(ibh);
return 0;
}
void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (unlikely(!nilfs_segment_usage_clean(su))) {
printk(KERN_WARNING "%s: segment %llu must be clean\n",
__func__, (unsigned long long)segnum);
kunmap_atomic(kaddr, KM_USER0);
return;
}
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr, KM_USER0);
nilfs_sufile_mod_counter(header_bh, -1, 1);
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
struct nilfs_snapshot_list *list;
__u64 curr, prev;
unsigned long curr_blkoff, prev_blkoff;
void *kaddr;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
if (nilfs_checkpoint_snapshot(cp)) {
ret = 0;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
kunmap_atomic(kaddr, KM_USER0);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_cp;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
list = &header->ch_snapshot_list;
curr_bh = header_bh;
get_bh(curr_bh);
curr = 0;
curr_blkoff = 0;
prev = le64_to_cpu(list->ssl_prev);
while (prev > cno) {
prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev);
curr = prev;
if (curr_blkoff != prev_blkoff) {
kunmap_atomic(kaddr, KM_USER0);
brelse(curr_bh);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr,
0, &curr_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(curr_bh->b_page, KM_USER0);
}
curr_blkoff = prev_blkoff;
cp = nilfs_cpfile_block_get_checkpoint(
cpfile, curr, curr_bh, kaddr);
list = &cp->cp_snapshot_list;
prev = le64_to_cpu(list->ssl_prev);
}
kunmap_atomic(kaddr, KM_USER0);
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_curr;
} else {
prev_bh = header_bh;
get_bh(prev_bh);
}
kaddr = kmap_atomic(curr_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, curr, curr_bh, kaddr);
list->ssl_prev = cpu_to_le64(cno);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
cp->cp_snapshot_list.ssl_next = cpu_to_le64(curr);
cp->cp_snapshot_list.ssl_prev = cpu_to_le64(prev);
nilfs_checkpoint_set_snapshot(cp);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(prev_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, prev, prev_bh, kaddr);
list->ssl_next = cpu_to_le64(cno);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
le64_add_cpu(&header->ch_nsnapshots, 1);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(prev_bh);
nilfs_mdt_mark_buffer_dirty(curr_bh);
nilfs_mdt_mark_buffer_dirty(cp_bh);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
brelse(prev_bh);
out_curr:
brelse(curr_bh);
out_header:
brelse(header_bh);
out_cp:
brelse(cp_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
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, 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;
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, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(
cpfile, cno, cp_bh, kaddr);
nicps = 0;
for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
WARN_ON(nilfs_checkpoint_snapshot(cp));
if (!nilfs_checkpoint_invalid(cp)) {
nilfs_checkpoint_set_invalid(cp);
nicps++;
}
}
if (nicps > 0) {
tnicps += nicps;
nilfs_mdt_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, KM_USER0);
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, KM_USER0);
brelse(cp_bh);
}
if (tnicps > 0) {
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh,
kaddr);
le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
kunmap_atomic(kaddr, KM_USER0);
}
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *header_bh, *next_bh, *prev_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
struct nilfs_snapshot_list *list;
__u64 next, prev;
void *kaddr;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
if (!nilfs_checkpoint_snapshot(cp)) {
ret = 0;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
list = &cp->cp_snapshot_list;
next = le64_to_cpu(list->ssl_next);
prev = le64_to_cpu(list->ssl_prev);
kunmap_atomic(kaddr, KM_USER0);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_cp;
if (next != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, 0,
&next_bh);
if (ret < 0)
goto out_header;
} else {
next_bh = header_bh;
get_bh(next_bh);
}
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_next;
} else {
prev_bh = header_bh;
get_bh(prev_bh);
}
kaddr = kmap_atomic(next_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, next, next_bh, kaddr);
list->ssl_prev = cpu_to_le64(prev);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(prev_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, prev, prev_bh, kaddr);
list->ssl_next = cpu_to_le64(next);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
cp->cp_snapshot_list.ssl_next = cpu_to_le64(0);
cp->cp_snapshot_list.ssl_prev = cpu_to_le64(0);
nilfs_checkpoint_clear_snapshot(cp);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
le64_add_cpu(&header->ch_nsnapshots, -1);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(next_bh);
nilfs_mdt_mark_buffer_dirty(prev_bh);
nilfs_mdt_mark_buffer_dirty(cp_bh);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
brelse(prev_bh);
out_next:
brelse(next_bh);
out_header:
brelse(header_bh);
out_cp:
brelse(cp_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_alloc - allocate a segment
* @sufile: inode of segment usage file
* @segnump: pointer to segment number
*
* Description: nilfs_sufile_alloc() allocates a clean segment.
*
* Return Value: On success, 0 is returned and the segment number of the
* allocated segment is stored in the place pointed by @segnump. On error, one
* of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No clean segment left.
*/
int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
{
struct buffer_head *header_bh, *su_bh;
struct nilfs_sufile_header *header;
struct nilfs_segment_usage *su;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
__u64 segnum, maxsegnum, last_alloc;
void *kaddr;
unsigned long nsegments, ncleansegs, nsus;
int ret, i, j;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr);
ncleansegs = le64_to_cpu(header->sh_ncleansegs);
last_alloc = le64_to_cpu(header->sh_last_alloc);
kunmap_atomic(kaddr, KM_USER0);
nsegments = nilfs_sufile_get_nsegments(sufile);
segnum = last_alloc + 1;
maxsegnum = nsegments - 1;
for (i = 0; i < nsegments; i += nsus) {
if (segnum >= nsegments) {
/* wrap around */
segnum = 0;
maxsegnum = last_alloc;
}
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
&su_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
nsus = nilfs_sufile_segment_usages_in_block(
sufile, segnum, maxsegnum);
for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
if (!nilfs_segment_usage_clean(su))
continue;
/* found a clean segment */
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_sufile_block_get_header(
sufile, header_bh, kaddr);
le64_add_cpu(&header->sh_ncleansegs, -1);
le64_add_cpu(&header->sh_ndirtysegs, 1);
header->sh_last_alloc = cpu_to_le64(segnum);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
brelse(su_bh);
*segnump = segnum;
goto out_header;
}
kunmap_atomic(kaddr, KM_USER0);
brelse(su_bh);
}
/* no segments left */
ret = -ENOSPC;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}